Reducing the Handover Delay in FMIPv6 Using Proactive Care-of Address Scheme

NASA Astrophysics Data System (ADS)

Li, Yong; Jin, Depeng; Su, Li; Zeng, Lieguang

To deal with the increasing number of mobile devices accessing the Internet and the increasing demands of mobility management, IETF has proposed Mobile IPv6 and its fast handover protocol FMIPv6. In FMIPv6, the possibility of Care-of Address (CoA) collision and the time for Return Routability (RR) procedure result in long handover delay, which makes it unsuitable for real-time applications. In this paper, we propose an improved handover scheme for FMIPv6, which reduces the handover delay by using proactive CoA acquisition, configuration and test method. In our proposal, collision-free CoA is proactively prepared, and the time for RR procedure does not contribute to the handover delay. Furthermore, we analyze our proposal's benefits and overhead tradeoff. The numerical results demonstrate that it outperforms the current schemes, such as FMIPv6 and enhanced FMIPv6, on the aspect of handover delay and packet transmission delay.

LMI designmethod for networked-based PID control

NASA Astrophysics Data System (ADS)

Souza, Fernando de Oliveira; Mozelli, Leonardo Amaral; de Oliveira, Maurício Carvalho; Palhares, Reinaldo Martinez

2016-10-01

In this paper, we propose a methodology for the design of networked PID controllers for second-order delayed processes using linear matrix inequalities. The proposed procedure takes into account time-varying delay on the plant, time-varying delays induced by the network and packed dropouts. The design is carried on entirely using a continuous-time model of the closed-loop system where time-varying delays are used to represent sampling and holding occurring in a discrete-time digital PID controller.

Peer-Implemented Time Delay Procedures on the Acquisition of Chained Tasks by Students with Moderate and Severe Disabilities

ERIC Educational Resources Information Center

Godsey, Janet Read; Schuster, John W.; Lingo, Amy Shearer; Collins, Belva C.; Kleinert, Harold L.

2008-01-01

This study evaluated the effectiveness of and reliability of peer tutors implementing a constant time delay procedure when teaching four high school students with moderate and severe disabilities to prepare foods using picture recipes. We used a multiple probe design across subjects to determine the effectiveness of the peer tutor implemented…

Using a Constant Time Delay Procedure to Teach Foundational Swimming Skills to Children with Autism

ERIC Educational Resources Information Center

Rogers, Laura; Hemmeter, Mary Louise; Wolery, Mark

2010-01-01

The purpose of this study was to evaluate the effectiveness of using a constant time delay procedure to teach foundational swimming skills to three children with autism. The skills included flutter kick, front-crawl arm strokes, and head turns to the side. A multiple-probe design across behaviors and replicated across participants was used.…

Identification of Printed Nonsense Words for an Individual with Autism: A Comparison of Constant Time Delay and Stimulus Fading

ERIC Educational Resources Information Center

Redhair, Emily

2011-01-01

This study compared a stimulus fading (SF) procedure with a constant time delay (CTD) procedure for identification of consonant-vowel-consonant (CVC) nonsense words for a participant with autism. An alternating treatments design was utilized through a computer-based format. Receptive identification of target words was evaluated using a computer…

Review of Recent Research Using Constant Time Delay to Teach Chained Tasks to Persons with Developmental Disabilities

ERIC Educational Resources Information Center

Dogoe, Maud; Banda, Devender R.

2009-01-01

We reviewed twelve studies that used the constant time delay (CTD) procedure to teach chained tasks to individuals with developmental disabilities from years 1996-2006. Variables analyzed include types of tasks that have been taught with the procedure, how effective CTD has been in teaching participants, and whether researchers have investigated…

Identification of Printed Nonsense Words for an Individual with Autism: A Comparison of Constant Time Delay and Stimulus Fading

ERIC Educational Resources Information Center

Redhair, Emily I.; McCoy, Kathleen M.; Zucker, Stanley H.; Mathur, Sarup R.; Caterino, Linda

2013-01-01

This study compared a stimulus fading (SF) procedure with a constant time delay (CTD) procedure for identification of consonant-vowel-consonant (CVC) nonsense words for a participant with autism. An alternating treatments design was utilized through a computer-based format. Receptive identification of target words was evaluated using a computer…

Teaching Generalized Reading of Product Warning Labels to Young Adults with Autism Using the Constant Time Delay Procedure

ERIC Educational Resources Information Center

Dogoe, Maud S.; Banda, Devender R.; Lock, Robin H.; Feinstein, Rita

2011-01-01

This study examined the effectiveness of the constant timed delay procedure for teaching two young adults with autism to read, define, and state the contextual meaning of keywords on product warning labels of common household products. Training sessions were conducted in the dyad format using flash cards. Results indicated that both participants…

The Effects of Time Delay and Increasing Prompt Hierarchy Strategies on the Acquisition of Purchasing Skills by Students with Severe Handicaps.

ERIC Educational Resources Information Center

McDonnell, John

1987-01-01

Two teaching strategies (constant time delay and increasing prompt hierarchy assistance) were compared in teaching four severely handicapped high school students to purchase snack items at a convenience store and fast food restaurant. Results indicated the time delay procedure was more effective. (DB)

Using Time Delay to Teach Literacy to Students with Severe Developmental Disabilities

ERIC Educational Resources Information Center

Browder, Diane; Ahlgrim-Delzell, Lynn; Spooner, Fred; Mims, Pamela J.; Baker, Joshua N.

2009-01-01

A review of the literature was conducted for articles published between 1975 and 2007 on the application of time delay as an instructional procedure to teach word and picture recognition to students with severe developmental disabilities in an effort to evaluate time delay as an evidence-based practice. A total of 30 experiments were analyzed…

Incidence and root causes of delays in emergency orthopaedic procedures: a single-centre experience of 36,017 consecutive cases over seven years.

PubMed

Caesar, Ulla; Karlsson, Jon; Hansson, Elisabeth

2018-01-01

Emergency surgery is unplanned by definition and patients are scheduled for surgery with minimal preparation. Some patients who have sustained emergency orthopaedic trauma or other conditions must be operated on immediately or within a few hours, while others can wait until the hospital's resources permit and/or the patients' health status has been optimised as needed. This may affect the prioritisation procedures for both emergency and elective surgery and might result in waiting lists, not only for planned procedures but also for emergencies. The main purpose of this retrospective, observational, single-centre study was to evaluate and describe for the number and reasons of delays, as well as waiting times in emergency orthopaedic surgery using data derived from the hospital's records and registers. All the emergency patients scheduled for emergency surgery whose procedures were rescheduled and delayed between 1 January 2007 and 31 December 2013 were studied. We found that 24% (8474) of the 36,017 patients scheduled for emergency surgeries were delayed and rescheduled at least once, some several times. Eighty per cent of these delays were due to organisational causes. Twenty-one per cent of all the delayed patients had surgery within 24 h, whilst 41% waited for more than 24 h, up to 3 days. A large number of the clinic's emergency orthopaedic procedures were rescheduled and delayed and the majority of the delays were related to organisational reasons. The results can be interpreted in two ways; first, organisational reasons are avoidable and the potential for improvement is great and, secondly and most importantly, the delays might negatively affect patient outcomes.

Effects of Constant Time Delay Procedure on the Halliwick's Method of Swimming Rotation Skills for Children with Autism

ERIC Educational Resources Information Center

Yilmaz, Ilker; Konukman, Ferman; Birkan, Binyamin; Ozen, Arzu; Yanardag, Mehmet; Camursoy, Ilhan

2010-01-01

Effects of a constant time delay procedure on the Halliwick's method of swimming rotation skills (i.e., vertical and lateral rotation) for children with autism were investigated. A single subject multiple baseline model across behaviors with probe conditions was used. Participants were three boys, 8-9 years old. Data were collected over a 10-week…

Procedural Adaptations for Use of Constant Time Delay to Teach Highly Motivating Words to Beginning Braille Readers

ERIC Educational Resources Information Center

Ivy, Sarah E.; Guerra, Jennifer A.; Hatton, Deborah D.

2017-01-01

Introduction: Constant time delay is an evidence-based practice to teach sight word recognition to students with a variety of disabilities. To date, two studies have documented its effectiveness for teaching braille. Methods: Using a multiple-baseline design, we evaluated the effectiveness of constant time delay to teach highly motivating words to…

Comparison of Constant Time Delay and Simultaneous Prompting Procedures: Teaching Functional Sight Words to Students with Intellectual Disabilities and Autism Spectrum Disorder

ERIC Educational Resources Information Center

Swain, Rasheeda; Lane, Justin D.; Gast, David L.

2015-01-01

Constant time delay (CTD) and simultaneous prompting (SP) are effective response prompting procedures for teaching students with moderate to severe disabilities. The purpose of this study was to compare the efficiency of CTD and SP when teaching functional sight words to four students, 8-11 years of age, with moderate intellectual disability (ID)…

The Effects of Constant Time Delay and Instructive Feedback on the Acquisition of English and Spanish Sight Words

ERIC Educational Resources Information Center

Appelman, Michelle; Vail, Cynthia O.; Lieberman-Betz, Rebecca G.

2014-01-01

The authors of this study evaluated the acquisition of instructive feedback information presented to four kindergarten children with mild delays taught in dyads using a constant time delay (CTD) procedure. They also assessed the learning of observational (dyadic partner) information within this instructional arrangement. A multiple probe design…

Delay-dependent coupling for a multi-agent LTI consensus system with inter-agent delays

NASA Astrophysics Data System (ADS)

Qiao, Wei; Sipahi, Rifat

2014-01-01

Delay-dependent coupling (DDC) is considered in this paper in a broadly studied linear time-invariant multi-agent consensus system in which agents communicate with each other under homogeneous delays, while attempting to reach consensus. The coupling among the agents is designed here as an explicit parameter of this delay, allowing couplings to autonomously adapt based on the delay value, and in order to guarantee stability and a certain degree of robustness in the network despite the destabilizing effect of delay. Design procedures, analysis of convergence speed of consensus, comprehensive numerical studies for the case of time-varying delay, and limitations are presented.

A TOTP-based enhanced route optimization procedure for mobile IPv6 to reduce handover delay and signalling overhead.

PubMed

Shah, Peer Azmat; Hasbullah, Halabi B; Lawal, Ibrahim A; Aminu Mu'azu, Abubakar; Tang Jung, Low

2014-01-01

Due to the proliferation of handheld mobile devices, multimedia applications like Voice over IP (VoIP), video conferencing, network music, and online gaming are gaining popularity in recent years. These applications are well known to be delay sensitive and resource demanding. The mobility of mobile devices, running these applications, across different networks causes delay and service disruption. Mobile IPv6 was proposed to provide mobility support to IPv6-based mobile nodes for continuous communication when they roam across different networks. However, the Route Optimization procedure in Mobile IPv6 involves the verification of mobile node's reachability at the home address and at the care-of address (home test and care-of test) that results in higher handover delays and signalling overhead. This paper presents an enhanced procedure, time-based one-time password Route Optimization (TOTP-RO), for Mobile IPv6 Route Optimization that uses the concepts of shared secret Token, time based one-time password (TOTP) along with verification of the mobile node via direct communication and maintaining the status of correspondent node's compatibility. The TOTP-RO was implemented in network simulator (NS-2) and an analytical analysis was also made. Analysis showed that TOTP-RO has lower handover delays, packet loss, and signalling overhead with an increased level of security as compared to the standard Mobile IPv6's Return-Routability-based Route Optimization (RR-RO).

LiDAR-IMU Time Delay Calibration Based on Iterative Closest Point and Iterated Sigma Point Kalman Filter.

PubMed

Liu, Wanli

2017-03-08

The time delay calibration between Light Detection and Ranging (LiDAR) and Inertial Measurement Units (IMUs) is an essential prerequisite for its applications. However, the correspondences between LiDAR and IMU measurements are usually unknown, and thus cannot be computed directly for the time delay calibration. In order to solve the problem of LiDAR-IMU time delay calibration, this paper presents a fusion method based on iterative closest point (ICP) and iterated sigma point Kalman filter (ISPKF), which combines the advantages of ICP and ISPKF. The ICP algorithm can precisely determine the unknown transformation between LiDAR-IMU; and the ISPKF algorithm can optimally estimate the time delay calibration parameters. First of all, the coordinate transformation from the LiDAR frame to the IMU frame is realized. Second, the measurement model and time delay error model of LiDAR and IMU are established. Third, the methodology of the ICP and ISPKF procedure is presented for LiDAR-IMU time delay calibration. Experimental results are presented that validate the proposed method and demonstrate the time delay error can be accurately calibrated.

A TOTP-Based Enhanced Route Optimization Procedure for Mobile IPv6 to Reduce Handover Delay and Signalling Overhead

PubMed Central

Shah, Peer Azmat; Hasbullah, Halabi B.; Lawal, Ibrahim A.; Aminu Mu'azu, Abubakar; Tang Jung, Low

2014-01-01

Due to the proliferation of handheld mobile devices, multimedia applications like Voice over IP (VoIP), video conferencing, network music, and online gaming are gaining popularity in recent years. These applications are well known to be delay sensitive and resource demanding. The mobility of mobile devices, running these applications, across different networks causes delay and service disruption. Mobile IPv6 was proposed to provide mobility support to IPv6-based mobile nodes for continuous communication when they roam across different networks. However, the Route Optimization procedure in Mobile IPv6 involves the verification of mobile node's reachability at the home address and at the care-of address (home test and care-of test) that results in higher handover delays and signalling overhead. This paper presents an enhanced procedure, time-based one-time password Route Optimization (TOTP-RO), for Mobile IPv6 Route Optimization that uses the concepts of shared secret Token, time based one-time password (TOTP) along with verification of the mobile node via direct communication and maintaining the status of correspondent node's compatibility. The TOTP-RO was implemented in network simulator (NS-2) and an analytical analysis was also made. Analysis showed that TOTP-RO has lower handover delays, packet loss, and signalling overhead with an increased level of security as compared to the standard Mobile IPv6's Return-Routability-based Route Optimization (RR-RO). PMID:24688398

Using Video to Bridge the Gap Between Problem Behavior and a Delayed Time-out Procedure.

PubMed

Coppage, Sara; Meindl, James N

2017-09-01

Treatment plans focused on problem behavior often include punishment contingencies to decrease problem behavior. Immediate punishers are typically more effective than delayed punishers, but immediate delivery of a punisher is not always possible. Strategies need to be developed to increase the suppressive effects of delayed punishers. This study demonstrated the effectiveness of a treatment package involving replaying a video recording of problem behavior immediately before delivering a 15 min delayed time-out. This treatment package may prove to be an accessible and inexpensive strategy when using delayed punishers.

Probability of Loss of Assured Safety in Systems with Multiple Time-Dependent Failure Modes: Incorporation of Delayed Link Failure in the Presence of Aleatory Uncertainty.

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

Helton, Jon C.; Brooks, Dusty Marie; Sallaberry, Cedric Jean-Marie.

Probability of loss of assured safety (PLOAS) is modeled for weak link (WL)/strong link (SL) systems in which one or more WLs or SLs could potentially degrade into a precursor condition to link failure that will be followed by an actual failure after some amount of elapsed time. The following topics are considered: (i) Definition of precursor occurrence time cumulative distribution functions (CDFs) for individual WLs and SLs, (ii) Formal representation of PLOAS with constant delay times, (iii) Approximation and illustration of PLOAS with constant delay times, (iv) Formal representation of PLOAS with aleatory uncertainty in delay times, (v) Approximationmore » and illustration of PLOAS with aleatory uncertainty in delay times, (vi) Formal representation of PLOAS with delay times defined by functions of link properties at occurrence times for failure precursors, (vii) Approximation and illustration of PLOAS with delay times defined by functions of link properties at occurrence times for failure precursors, and (viii) Procedures for the verification of PLOAS calculations for the three indicated definitions of delayed link failure.« less

A Comparison of Flexible Prompt Fading and Constant Time Delay for Five Children with Autism

ERIC Educational Resources Information Center

Soluaga, Doris; Leaf, Justin B.; Taubman, Mitchell; McEachin, John; Leaf, Ron

2008-01-01

Given the increasing rates of autism, identifying prompting procedures that can assist in the development of more optimal learning opportunities for this population is critical. Extensive empirical research exists supporting the effectiveness of various prompting strategies. Constant time delay (CTD) is a highly implemented prompting procedure…

LiDAR-IMU Time Delay Calibration Based on Iterative Closest Point and Iterated Sigma Point Kalman Filter

PubMed Central

Liu, Wanli

2017-01-01

The time delay calibration between Light Detection and Ranging (LiDAR) and Inertial Measurement Units (IMUs) is an essential prerequisite for its applications. However, the correspondences between LiDAR and IMU measurements are usually unknown, and thus cannot be computed directly for the time delay calibration. In order to solve the problem of LiDAR-IMU time delay calibration, this paper presents a fusion method based on iterative closest point (ICP) and iterated sigma point Kalman filter (ISPKF), which combines the advantages of ICP and ISPKF. The ICP algorithm can precisely determine the unknown transformation between LiDAR-IMU; and the ISPKF algorithm can optimally estimate the time delay calibration parameters. First of all, the coordinate transformation from the LiDAR frame to the IMU frame is realized. Second, the measurement model and time delay error model of LiDAR and IMU are established. Third, the methodology of the ICP and ISPKF procedure is presented for LiDAR-IMU time delay calibration. Experimental results are presented that validate the proposed method and demonstrate the time delay error can be accurately calibrated. PMID:28282897

Constant Time Delay: One Way to Provide Positive Behavioral Support for Students with Emotional and Behavioral Disorders

ERIC Educational Resources Information Center

Stevens, Kay B.; Lingo, Amy S.

2005-01-01

Teachers of students with emotional and behavioral disorders (EBD) understand conceptually, emotionally, and legally the importance of using research-based procedures as well as positive behavioral supports. One way to provide positive behavioral support for students with EBD is constant time delay (CTD). CTD is an instructional delivery procedure…

State feedback controller design for the synchronization of Boolean networks with time delays

NASA Astrophysics Data System (ADS)

Li, Fangfei; Li, Jianning; Shen, Lijuan

2018-01-01

State feedback control design to make the response Boolean network synchronize with the drive Boolean network is far from being solved in the literature. Motivated by this, this paper studies the feedback control design for the complete synchronization of two coupled Boolean networks with time delays. A necessary condition for the existence of a state feedback controller is derived first. Then the feedback control design procedure for the complete synchronization of two coupled Boolean networks is provided based on the necessary condition. Finally, an example is given to illustrate the proposed design procedure.

Flip-flop resolving time test circuit

NASA Technical Reports Server (NTRS)

Rosenberger, F.; Chaney, T. J.

1982-01-01

Integrated circuit (IC) flip-flop resolving time parameters are measured by wafer probing, without need of dicing or bonding, throught the incorporation of test structures on an IC together with the flip-flop to be measured. Several delays that are fabricated as part of the test circuit, including a voltage-controlled delay with a resolution of a few picosecs, are calibrated as part of the test procedure by integrating them into, and out of, the delay path of a ring oscillator. Each of the delay values is calculated by subtracting the period of the ring oscillator with the delay omitted from the period with the delay included. The delay measurement technique is sufficiently general for other applications. The technique is illustrated for the case of the flip-flop parameters of a 5-micron feature size NMOS circuit.

A hybrid approach to parameter identification of linear delay differential equations involving multiple delays

NASA Astrophysics Data System (ADS)

Marzban, Hamid Reza

2018-05-01

In this paper, we are concerned with the parameter identification of linear time-invariant systems containing multiple delays. The approach is based upon a hybrid of block-pulse functions and Legendre's polynomials. The convergence of the proposed procedure is established and an upper error bound with respect to the L2-norm associated with the hybrid functions is derived. The problem under consideration is first transformed into a system of algebraic equations. The least squares technique is then employed for identification of the desired parameters. Several multi-delay systems of varying complexity are investigated to evaluate the performance and capability of the proposed approximation method. It is shown that the proposed approach is also applicable to a class of nonlinear multi-delay systems. It is demonstrated that the suggested procedure provides accurate results for the desired parameters.

Improving the timeliness of procedures in a pediatric endoscopy suite.

PubMed

Tomer, Gitit; Choi, Steven; Montalvo, Andrea; Sutton, Sheila; Thompson, John; Rivas, Yolanda

2014-02-01

Pediatric endoscopic procedures are essential in the evaluation and treatment of gastrointestinal diseases in children. Although pediatric endoscopists are greatly interested in increasing efficiency and through-put in pediatric endoscopy units, there is scarcely any literature on this critical process. The goal of this study was to improve the timeliness of pediatric endoscopy procedures at Children's Hospital at Montefiore. In June 2010, a pediatric endoscopy quality improvement initiative was formed at Children's Hospital at Montefiore. We identified patient-, equipment-, and physician-related causes for case delays. Pareto charts, cause and effect diagrams, process flow mapping, and statistical process control charts were used for analysis. From June 2010 to December 2012, we were able to significantly decrease the first case endoscopy delay from an average of 17 to 10 minutes (P < .001), second case delay from 39 to 25 minutes (P = .01), third case delay from 61 to 45 minutes (P = .05), and fourth case delay from 79 to 51 minutes (P = .05). Total delay time decreased from 196 to 131 minutes, resulting in a reduction of 65 minutes (P = .02). From June 2010 to August 2011 (preintervention period), an average of 36% of first endoscopy cases started within 5 minutes, 51% within 10 minutes, and 61% within 15 minutes of the scheduled time. From September 2011 to December 2012 (postintervention period), the percentage of cases starting within 5 minutes, 10 minutes, and 15 minutes increased to 47% (P = .07), 61% (P = .04), and 79% (P = .01), respectively. Applying quality improvement methods and tools helped improve pediatric endoscopy timeliness and significantly decreased total delays.

The influence of procedure delay on resource use: a national study of patients with open tibial fracture.

PubMed

Sears, Erika Davis; Burke, James F; Davis, Matthew M; Chung, Kevin C

2013-03-01

The purpose of this study was to (1) understand national variation in delay of emergency procedures in patients with open tibial fracture at the hospital level and (2) compare length of stay and cost in patients cared for at the best- and worst-performing hospitals for delay. The authors retrospectively analyzed the 2003 to 2009 Nationwide Inpatient Sample. Adult patients with open tibial fracture were included. Hospital probability of delay in performing emergency procedures beyond the day of admission was calculated. Multilevel linear regression random-effects models were created to evaluate the relationship between the treating hospital's tendency for delay (in quartiles) and the log-transformed outcomes of length of stay and cost. The final sample included 7029 patients from 332 hospitals. Patients treated at hospitals in the fourth (worst) quartile for delay were estimated to have 12 percent (95 percent CI, 2 to 21 percent) higher cost compared with patients treated at hospitals in the first quartile. In addition, patients treated at hospitals in the fourth quartile had an estimated 11 percent (95 percent CI, 4 to 17 percent) longer length of stay compared with patients treated at hospitals in the first quartile. Patients with open tibial fracture treated at hospitals with more timely initiation of surgical care had lower cost and shorter length of stay than patients treated at hospitals with less timely initiation of care. Policies directed toward mitigating variation in care may reduce unnecessary waste.

Noise Effects Upon a Simple Timing Channel

DTIC Science & Technology

1990-12-21

used to quantify the resulting information flow across the chan- nel. Possible Trojan Horse strategies are also discussed. 14. SUBJECT TERMS 15. NUMBER...performed by a program referred to as a Trojan Horse . The Trojan Horse has the ability to instigate the delaying procedure to low, read high’s file. code it...and pass it through this delaying procedure. Such a means of communication between high and low, with or without the Trojan Horse in place, will be

Using Video Prompting and Constant Time Delay to Teach an Internet Search Basic Skill to Students with Intellectual Disabilities

ERIC Educational Resources Information Center

Zisimopoulos, Dimitrios; Sigafoos, Jeff; Koutromanos, George

2011-01-01

We evaluated a video prompting and a constant time delay procedure for teaching three primary school students with moderate intellectual disabilities to access the Internet and download pictures related to participation in a classroom History project. Video clips were used as an antecedent prompt and as an error correction technique within a…

Anticontrol of chaos in continuous-time systems via time-delay feedback.

PubMed

Wang, Xiao Fan; Chen, Guanrong; Yu, Xinghuo

2000-12-01

In this paper, a systematic design approach based on time-delay feedback is developed for anticontrol of chaos in a continuous-time system. This anticontrol method can drive a finite-dimensional, continuous-time, autonomous system from nonchaotic to chaotic, and can also enhance the existing chaos of an originally chaotic system. Asymptotic analysis is used to establish an approximate relationship between a time-delay differential equation and a discrete map. Anticontrol of chaos is then accomplished based on this relationship and the differential-geometry control theory. Several examples are given to verify the effectiveness of the methodology and to illustrate the systematic design procedure. (c) 2000 American Institute of Physics.

Temporal Discontiguity Is neither Necessary nor Sufficient for Learning-Induced Effects on Adult Neurogenesis

PubMed Central

Leuner, Benedetta; Waddell, Jaylyn; Gould, Elizabeth; Shors, Tracey J.

2012-01-01

Some, but not all, types of learning and memory can influence neurogenesis in the adult hippocampus. Trace eyeblink conditioning has been shown to enhance the survival of new neurons, whereas delay eyeblink conditioning has no such effect. The key difference between the two training procedures is that the conditioning stimuli are separated in time during trace but not delay conditioning. These findings raise the question of whether temporal discontiguity is necessary for enhancing the survival of new neurons. Here we used two approaches to test this hypothesis. First, we examined the influence of a delay conditioning task in which the duration of the conditioned stimulus (CS) was increased nearly twofold, a procedure that critically engages the hippocampus. Although the CS and unconditioned stimulus are contiguous, this very long delay conditioning procedure increased the number of new neurons that survived. Second, we examined the influence of learning the trace conditioned response (CR) after having acquired the CR during delay conditioning, a procedure that renders trace conditioning hippocampal-independent. In this case, trace conditioning did not enhance the survival of new neurons. Together, these results demonstrate that associative learning increases the survival of new neurons in the adult hippocampus, regardless of temporal contiguity. PMID:17192426

The Effects of Embedded Skill Instruction on the Acquisition of Target and Nontarget Skills in Preschoolers with Developmental Delays.

ERIC Educational Resources Information Center

Daugherty, Stefanie; Grisham-Brown, Jennifer; Hemmeter, Mary Louise

2001-01-01

In the current study, a constant time delay (CTD) procedure was embedded in classroom activities and routines to teach counting to three preschool children with speech and language delays. CTD was effective in teaching numbers to all three children. One child out of two also was able to acquire non-target information. (Contains references.) (CR)

Phase-Based Adaptive Estimation of Magnitude-Squared Coherence Between Turbofan Internal Sensors and Far-Field Microphone Signals

NASA Technical Reports Server (NTRS)

Miles, Jeffrey Hilton

2015-01-01

A cross-power spectrum phase based adaptive technique is discussed which iteratively determines the time delay between two digitized signals that are coherent. The adaptive delay algorithm belongs to a class of algorithms that identifies a minimum of a pattern matching function. The algorithm uses a gradient technique to find the value of the adaptive delay that minimizes a cost function based in part on the slope of a linear function that fits the measured cross power spectrum phase and in part on the standard error of the curve fit. This procedure is applied to data from a Honeywell TECH977 static-engine test. Data was obtained using a combustor probe, two turbine exit probes, and far-field microphones. Signals from this instrumentation are used estimate the post-combustion residence time in the combustor. Comparison with previous studies of the post-combustion residence time validates this approach. In addition, the procedure removes the bias due to misalignment of signals in the calculation of coherence which is a first step in applying array processing methods to the magnitude squared coherence data. The procedure also provides an estimate of the cross-spectrum phase-offset.

The analysis of delays in simulator digital computing systems. Volume 1: Formulation of an analysis approach using a central example simulator model

NASA Technical Reports Server (NTRS)

Heffley, R. K.; Jewell, W. F.; Whitbeck, R. F.; Schulman, T. M.

1980-01-01

The effects of spurious delays in real time digital computing systems are examined. Various sources of spurious delays are defined and analyzed using an extant simulator system as an example. A specific analysis procedure is set forth and four cases are viewed in terms of their time and frequency domain characteristics. Numerical solutions are obtained for three single rate one- and two-computer examples, and the analysis problem is formulated for a two-rate, two-computer example.

Time-delayed feedback technique for suppressing instabilities in time-periodic flow

NASA Astrophysics Data System (ADS)

Shaabani-Ardali, Léopold; Sipp, Denis; Lesshafft, Lutz

2017-11-01

A numerical method is presented that allows to compute time-periodic flow states, even in the presence of hydrodynamic instabilities. The method is based on filtering nonharmonic components by way of delayed feedback control, as introduced by Pyragas [Phys. Lett. A 170, 421 (1992), 10.1016/0375-9601(92)90745-8]. Its use in flow problems is demonstrated here for the case of a periodically forced laminar jet, subject to a subharmonic instability that gives rise to vortex pairing. The optimal choice of the filter gain, which is a free parameter in the stabilization procedure, is investigated in the context of a low-dimensional model problem, and it is shown that this model predicts well the filter performance in the high-dimensional flow system. Vortex pairing in the jet is efficiently suppressed, so that the unstable periodic flow state in response to harmonic forcing is accurately retrieved. The procedure is straightforward to implement inside any standard flow solver. Memory requirements for the delayed feedback control can be significantly reduced by means of time interpolation between checkpoints. Finally, the method is extended for the treatment of periodic problems where the frequency is not known a priori. This procedure is demonstrated for a three-dimensional cubic lid-driven cavity in supercritical conditions.

Influence of age on delayed surgical treatment of proximal femoral fractures

PubMed Central

Gomes, Lisiane Pinto; do Nascimento, Leandra Delfim; Campos, Tulio Vinicius de Oliveira; Paiva, Edson Barreto; de Andrade, Marco Antonio Percope; Guimarães, Henrique Cerqueira

2015-01-01

ABSTRACT OBJECTIVE : To investigate the influence of patients' age on the delay between diagnosis and surgical treatment of proximal femoral fractures METHODS : This is a retrospective study, con-ducted at a tertiary university hospital, including all patients admitted with proximal femoral fractures between March 2013 and March 2014. The participants were categorized into four groups according to age levels. The groups were compared according to demographics, comorbidities, fracture type, trau-ma circumstances, and time between diagnosis and surgical procedure RESULTS : One hundred and sixty one patients were included, 37 adults and 124 elderly. Among adults, the mean delay between diagnosis and surgical procedure was 6.4±5.3 days; among elderly the delay was 9.5±7.6 days. There was a progressive increase in the delay from the young-adults group through the elderly individuals (Kruskal-Wallis: 13.7; p=0.003) CONCLUSION : In spite of being the patients most susceptible to complications due to surgical delay, the elderly individuals pre-sented the longest delays from admission to surgical treatment. Level of Evidence III, Retrospective Study. PMID:27057145

Computer laboratory notification system via short message service to reduce health care delays in management of tuberculosis in Taiwan.

PubMed

Chen, Tun-Chieh; Lin, Wei-Ru; Lu, Po-Liang; Lin, Chun-Yu; Lin, Shu-Hui; Lin, Chuen-Ju; Feng, Ming-Chu; Chiang, Horn-Che; Chen, Yen-Hsu; Huang, Ming-Shyan

2011-06-01

We investigated the impacts of introducing an expedited acid-fast bacilli (AFB) smear laboratory procedure and an automatic, real-time laboratory notification system by short message with mobile phones on delays in prompt isolation of patients with pulmonary tuberculosis (TB). We analyzed the data for all patients with active pulmonary tuberculosis at a hospital in Kaohsiung, Taiwan, a 1,600-bed medical center, during baseline (January 2004 to February 2005) and intervention (July 2005 to August 2006) phases. A total of 96 and 127 patients with AFB-positive TB was reported during the baseline and intervention phases, respectively. There were significant decreases in health care system delays (ie, laboratory delays: reception of sputum to reporting, P < .001; response delays: reporting to patient isolation, P = .045; and interval from admission to patient isolation, P < .001) during the intervention phase. Significantly fewer nurses were exposed to each patient with active pulmonary TB during the intervention phase (P = .039). Implementation of expedited AFB smear laboratory procedures and an automatic, real-time laboratory mobile notification system significantly decreased delays in the diagnosis and isolation of patients with active TB. Copyright © 2011 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

When good pigeons make bad decisions: Choice with probabilistic delays and outcomes.

PubMed

Pisklak, Jeffrey M; McDevitt, Margaret A; Dunn, Roger M; Spetch, Marcia L

2015-11-01

Pigeons chose between an (optimal) alternative that sometimes provided food after a 10-s delay and other times after a 40-s delay and another (suboptimal) alternative that sometimes provided food after 10 s but other times no food after 40 s. When outcomes were not signaled during the delays, pigeons strongly preferred the optimal alternative. When outcomes were signaled, choices of the suboptimal alternative increased and most pigeons preferred the alternative that provided no food after the long delay despite the cost in terms of obtained food. The pattern of results was similar whether the short delays occurred on 25% or 50% of the trials. Shortening the 40-s delay to food sharply reduced suboptimal choices, but shortening the delay to no food had little effect. The results suggest that a signaled delay to no food does not punish responding in probabilistic choice procedures. The findings are discussed in terms of conditioned reinforcement by signals for good news. © Society for the Experimental Analysis of Behavior.

Comparison of Simultaneous Prompting and Constant Time Delay Procedures in Teaching Children with Autism the Responses to Questions about Personal Information

ERIC Educational Resources Information Center

Akmanoglu, Nurgul; Kurt, Onur; Kapan, Alper

2015-01-01

The aim of the current study was to compare simultaneous prompting (SP) and constant time delay (CTD) in terms of their effectiveness and efficiency in teaching children with autism how to respond to questions about personal information. The adapted alternating treatments model was used in the study. Three male students with autism aged 4, 6, and…

Differential Effects of Two Spelling Procedures on Acquisition, Maintenance and Adaption to Reading

ERIC Educational Resources Information Center

Cates, Gary L.; Dunne, Megan; Erkfritz, Karyn N.; Kivisto, Aaron; Lee, Nicole; Wierzbicki, Jennifer

2007-01-01

An alternating treatments design was used to assess the effects of a constant time delay (CTD) procedure and a cover-copy-compare (CCC) procedure on three students' acquisition, subsequent maintenance, and adaptation (i.e., application) of acquired spelling words to reading passages. Students were randomly presented two trials of word lists from…

The Influence of Procedure Delay on Resource Utilization: A National Study of Patients with Open Tibial Fracture

PubMed Central

Sears, Erika Davis; Burke, James F.; Davis, Matthew M.; Chung, Kevin C.

2016-01-01

Background The purpose of this study is to 1) understand national variation in delay of emergency procedures in patients with open tibial fracture at the hospital level and 2) compare length of stay (LOS) and cost in patients cared for at the best and worst performing hospitals for delay. Methods We retrospectively analyzed the 2003 – 2009 Nationwide Inpatient Sample. Adult patients with primary diagnosis of open tibial fracture were selected for inclusion. We calculated hospital probability of delay of emergency procedures beyond the day of admission (day 0). Multilevel linear regression random effects models were created to evaluate the relationship between the treating hospital’s tendency for delay (in quartiles) and the log-transformed outcomes of LOS and cost, while adjusting for patient and hospital variables. Results The final sample included 7,029 patients from 332 hospitals. Adjusted analyses demonstrate that patients treated at hospitals in the fourth (worst) quartile for delay were estimated to have 12% (95% CI 2–21%) higher cost compared to patients treated at hospitals in the first quartile. In addition, patients treated at hospitals in the fourth quartile had an estimated 11% (CI 4–17%) longer LOS compared to patients treated at hospitals in the first quartile. Conclusions Patients with open tibial fracture treated at hospitals with more timely initiation of surgical care had lower cost and shorter LOS than patients treated at hospitals with less timely initiation of care. Policies directed toward mitigating variation in care are not only beneficial for patient outcomes, but may also reduce unnecessary waste. Level II (Prognostic) PMID:23142940

Delayed flap approach procedures for noise abatement and fuel conservation

NASA Technical Reports Server (NTRS)

Edwards, F. G.; Bull, J. S.; Foster, J. D.; Hegarty, D. M.; Drinkwater, F. J., III

1976-01-01

The NASA/Ames Research Center is currently investigating the delayed flap approach during which pilot actions are determined and prescribed by an onboard digital computer. The onboard digital computer determines the proper timing for the deployment of the landing gear and flaps based on the existing winds and airplane gross weight. Advisory commands are displayed to the pilot. The approach is flown along the conventional ILS glide slope but is initiated at a higher airspeed and in a clean aircraft configuration that allows for low thrust and results in reduced noise and fuel consumption. Topics discussed include operational procedures, pilot acceptability of these procedures, and fuel/noise benefits resulting from flight tests and simulation.

Timing and teamwork--an observational pilot study of patients referred to a Rapid Response Team with the aim of identifying factors amenable to re-design of a Rapid Response System.

PubMed

Peebles, Emma; Subbe, Christian P; Hughes, Paul; Gemmell, Les

2012-06-01

Rapid Response Teams aim to accelerate recognition and treatment of acutely unwell patients. Delays in delivery might undermine efficiency of the intervention. Our understanding of the causes of these delays is, as yet, incomplete. To identify modifiable causes of delays in the treatment of critically ill patients outside intensive care with a focus on factors amenable to system design. Review of care records and direct observation with process mapping of care delivered to 17 acutely unwell patients attended by a Rapid Response Team in a District General Hospital in the United Kingdom. Delays were defined as processes with no added value for patient care. Essential diagnostic and therapeutic procedures accounted for only 31% of time of care processes. Causes for delays could be classified into themes as (1) delays in call-out of the Rapid Response Team, (2) problems with team cohesion including poor communication and team efficiency and (3) lack of resources including lack of first line antibiotics, essential equipment, experienced staff and critical care beds. We identified a number of potentially modifiable causes for delays in care of acutely ill patients. Improved process design could include automated call-outs, a dedicated kit for emergency treatment in relevant clinical areas, increased usage of standard operating procedures and staff training using crew resource management techniques. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Report: EPA Needs Policies and Procedures to Manage Public Pesticide Petitions in a Transparent and Efficient Manner

EPA Pesticide Factsheets

Report #16-P-0019, October 27, 2015. OPP’s lack of policies and procedures to manage public pesticide petitions in a transparent and efficient manner can result in unreasonable delay lawsuits costing the agency time and resources.

Review of Research on Sight Word Instruction.

ERIC Educational Resources Information Center

Browder, Diane M.; Lalli, Joseph S.

1991-01-01

This review of 20 years of literature on sight word instruction for individuals with handicaps examines effectiveness data for procedures teaching word recognition and comprehension. Covered are "errorless procedures," prompt elimination, stimulus fading, time delay, easy to hard discrimination, and trial and error with feedback. Two tables…

Using Video Prompting to Teach Cooking Skills to Secondary Students with Moderate Disabilities

ERIC Educational Resources Information Center

Graves, Tara B.; Collins, Belva C.; Schuster, John W.; Kleinert, Harold

2005-01-01

Three secondary students with moderate disabilities acquired cooking skills through a constant time delay procedure used with video prompting. A multiple probe design was used to evaluate effectiveness of the procedure to teach preparation of a food item (a) on a stove, (b) in a microwave, and (c) on a counter top. The procedure was effective for…

A New Local Bipolar Autoassociative Memory Based on External Inputs of Discrete Recurrent Neural Networks With Time Delay.

PubMed

Zhou, Caigen; Zeng, Xiaoqin; Luo, Chaomin; Zhang, Huaguang

In this paper, local bipolar auto-associative memories are presented based on discrete recurrent neural networks with a class of gain type activation function. The weight parameters of neural networks are acquired by a set of inequalities without the learning procedure. The global exponential stability criteria are established to ensure the accuracy of the restored patterns by considering time delays and external inputs. The proposed methodology is capable of effectively overcoming spurious memory patterns and achieving memory capacity. The effectiveness, robustness, and fault-tolerant capability are validated by simulated experiments.In this paper, local bipolar auto-associative memories are presented based on discrete recurrent neural networks with a class of gain type activation function. The weight parameters of neural networks are acquired by a set of inequalities without the learning procedure. The global exponential stability criteria are established to ensure the accuracy of the restored patterns by considering time delays and external inputs. The proposed methodology is capable of effectively overcoming spurious memory patterns and achieving memory capacity. The effectiveness, robustness, and fault-tolerant capability are validated by simulated experiments.

Aeroservoelastic stabilization technique refinement for hypersonic flight vehicles

NASA Technical Reports Server (NTRS)

Cheng, Peter Y.; Chan, Samuel Y.; Myers, Thomas T.; Klyde, David H.; Mcruer, Duane T.

1992-01-01

Conventional gain-stabilization techniques introduce low frequency effective time delays which can be troublesome from the viewpoint of SSTOV vehicles' flying qualities. These time delays can be alleviated through a blending of gain-stabilization and phase-stabilization techniques; the resulting hybrid phase stabilization (HPS) for the low-frequency structural modes has been noted to have greater residual response than a conventional gain-stabilizer design. HPS design procedures are presently refined, and residual response metrics are developed.

Performance limitations of bilateral force reflection imposed by operator dynamic characteristics

NASA Technical Reports Server (NTRS)

Chapel, Jim D.

1989-01-01

A linearized, single-axis model is presented for bilateral force reflection which facilitates investigation into the effects of manipulator, operator, and task dynamics, as well as time delay and gain scaling. Structural similarities are noted between this model and impedance control. Stability results based upon this model impose requirements upon operator dynamic characteristics as functions of system time delay and environmental stiffness. An experimental characterization reveals the limited capabilities of the human operator to meet these requirements. A procedure is presented for determining the force reflection gain scaling required to provide stability and acceptable operator workload. This procedure is applied to a system with dynamics typical of a space manipulator, and the required gain scaling is presented as a function of environmental stiffness.

The effects of local nitroglycerin on the surgical delay procedure in prefabricated flaps by vascular implant in rats.

PubMed

Sá, Jairo Zacchê de; Aguiar, José Lamartine de Andrade; Cruz, Adriana Ferreira; Schuler, Alexandre Ricardo Pereira; Lima, José Ricardo Alves de; Marques, Olga Martins

2012-12-01

To evaluate the effect of local nitroglycerin on the viable area of a prefabricated flap for vascular implant in rats, and to investigate the surgical delay procedure. A femoral pedicle was implanted under the skin of the abdominal wall in forty Wistar rats. The animals were divided into four groups of ten: group 1 - without surgical delay procedure and local nitroglycerin; group 2 - with surgical delay procedure, but without local nitroglycerin; group 3 - without surgical delay procedure, but with local nitroglycerin; and group 4 - with simultaneous surgical delay procedure and local nitroglycerin. The percentages of the viable areas, in relation to the total flap, were calculated using AutoCAD R 14. The mean percentage value of the viable area was 8.9% in the group 1. 49.4% in the group 2; 8.4% in the group 3 and 1.1% in the group 4. There was significant difference between groups 1 and 2 (p=0.005), 1 and 4 (p=0.024), 2 and 3 (p=0.003), 2 and 4 (p=0.001). These results support the hypothesis that the closure of the arterial venous channels is responsible for the phenomenon of surgical delay procedure. Local nitroglycerin did not cause an increase in the prefabricated viable flap area by vascular implantation and decreased the viable flap area that underwent delay procedures.

Zooming in on children's behavior during delay of gratification: Disentangling impulsigenic and volitional processes underlying self-regulation.

PubMed

Neuenschwander, Regula; Blair, Clancy

2017-02-01

When delaying gratification, both motivational and regulatory processes are likely to be at play; however, the relative contributions of motivational and regulatory influences on delay behavior are unclear. By examining behavioral responses during a delay task, this study sought to examine the motivational (anticipatory behavior) and regulatory mechanisms (executive function and self-control strategies) underlying children's self-regulation. The participants, 65 5- to 9-year-old children (M age =7.19years, SD=0.89), were video-recorded during a delay procedure and later coded for anticipatory behaviors (e.g., gazing intensely at the tablet) and self-control strategies. Children also completed two executive function (EF) tasks. We found that anticipatory behavior was curvilinearly related to delay time. Children showing either very low or very high levels of anticipatory behavior were not able to wait the entire time. Furthermore, our results indicated that anticipatory behavior interacted with EF to predict delay time. Specifically, anticipatory behavior was negatively related to delay time only if EF abilities were low. Finally, self-control strategies also interacted with EF to predict children's ability to delay. Spontaneous engagement in self-control strategies such as fidgeting and engagement in alternative activities were beneficial for children with low EF but were unrelated to delay time for children with high EF. Results indicate the value of examining motivational and regulatory influences on delay behavior. Lapses in self-regulation may be due to the combination of powerful impulsigenic (i.e., anticipatory behavior) and weak volitional processes (i.e., EF, self-control strategies). Copyright © 2016. Published by Elsevier Inc.

Calibration of Galileo signals for time metrology.

PubMed

Defraigne, Pascale; Aerts, Wim; Cerretto, Giancarlo; Cantoni, Elena; Sleewaegen, Jean-Marie

2014-12-01

Using global navigation satellite system (GNSS) signals for accurate timing and time transfer requires the knowledge of all electric delays of the signals inside the receiving system. GNSS stations dedicated to timing or time transfer are classically calibrated only for Global Positioning System (GPS) signals. This paper proposes a procedure to determine the hardware delays of a GNSS receiving station for Galileo signals, once the delays of the GPS signals are known. This approach makes use of the broadcast satellite inter-signal biases, and is based on the ionospheric delay measured from dual-frequency combinations of GPS and Galileo signals. The uncertainty on the so-determined hardware delays is estimated to 3.7 ns for each isolated code in the L5 frequency band, and 4.2 ns for the ionosphere-free combination of E1 with a code of the L5 frequency band. For the calibration of a time transfer link between two stations, another approach can be used, based on the difference between the common-view time transfer results obtained with calibrated GPS data and with uncalibrated Galileo data. It is shown that the results obtained with this approach or with the ionospheric method are equivalent.

[Small amounts of milk added to coffee or tea can be allowed before surgery].

PubMed

Miranda, Kenia S; Kristensen, Billy B

2018-03-26

The ingestion of milk is not allowed within six hours before elective procedures requiring anaesthesia or sedation, because milk is considered a solid food. However, the impact of milk suspended in coffee or tea consumed up to two hours before anaesthesia is less certain, yet fasting guidelines demand surgery to be delayed or rescheduled. Studies investigating ingestion of liquids with small amounts of milk have not demonstrated delayed emptying of the stomach, thereby increasing the risk of aspiration in elective procedures. Maybe it is time to adjust the fasting recommendations.

Effects of Acute and Chronic Cocaine Administration on Titrating-Delay Matching-to-Sample Performance

ERIC Educational Resources Information Center

Kangas, Brian D.; Branch, Marc N.

2012-01-01

The effects of cocaine were examined under a titrating-delay matching-to-sample procedure. In this procedure, the delay between sample stimulus offset and comparison stimuli onset adjusts as a function of the subject's performance. Specifically, matches increase the delay and mismatches decrease the delay. Titrated delay values served as the…

Operating room efficiency improvement after implementation of a postoperative team assessment.

PubMed

Porta, Christopher R; Foster, Andrew; Causey, Marlin W; Cordier, Patricia; Ozbirn, Roger; Bolt, Stephen; Allison, Dennis; Rush, Robert

2013-03-01

Operating room time is highly resource intensive, and delays can be a source of lost revenue and surgeon frustration. Methods to decrease these delays are important not only for patient care, but to maximize operating room resource utilization. The purpose of this study was to determine the root cause of operating room delays in a standardized manner to help improve overall operating room efficiency. We performed a single-center prospective observational study analyzing operating room utilization and efficiency after implementing an executive-driven standardized postoperative team debriefing system from January 2010 to December 2010. A total of 11,342 procedures were performed over the 1-y study period (elective 86%, urgent 11%, and emergent 3%), with 1.3 million min of operating room time, 865,864 min of surgeon operative time (62.5%), and 162,958 min of anesthesia time (11.8%). Overall, the average operating room delay was 18 min and varied greatly based on the surgical specialty. The longest delays were due to need for radiology (40 min); other significant delays were due to supply issues (22.7 min), surgeon issues (18 min), nursing issues (14 min), and room turnover (14 min). Over the 1-y period, there was a decrease in mean delay duration, averaging a decrease in delay of 0.147 min/mo with an overall 9% decrease in the mean delay times. With regard to overall operating room utilization, there was a 39% decrease in overall un-utilized available OR time that was due to delays, improving efficiency by 2334 min (212 min/mo). During this study interval no sentinel events occurred in the operating room. A standardized postoperative debrief tracking system is highly beneficial in identifying and reducing overall operative delays and improving operating room utilization. Published by Elsevier Inc.

Autonomous Mission Operations

NASA Technical Reports Server (NTRS)

Frank, Jeremy; Spirkovska, Lilijana; McCann, Rob; Wang, Lui; Pohlkamp, Kara; Morin, Lee

2012-01-01

NASA's Advanced Exploration Systems Autonomous Mission Operations (AMO) project conducted an empirical investigation of the impact of time-delay on todays mission operations, and of the effect of processes and mission support tools designed to mitigate time-delay related impacts. Mission operation scenarios were designed for NASA's Deep Space Habitat (DSH), an analog spacecraft habitat, covering a range of activities including nominal objectives, DSH system failures, and crew medical emergencies. The scenarios were simulated at time-delay values representative of Lunar (1.2-5 sec), Near Earth Object (NEO) (50 sec) and Mars (300 sec) missions. Each combination of operational scenario and time-delay was tested in a Baseline configuration, designed to reflect present-day operations of the International Space Station, and a Mitigation configuration in which a variety of software tools, information displays, and crew-ground communications protocols were employed to assist both crews and Flight Control Team (FCT) members with the long-delay conditions. Preliminary findings indicate: 1) Workload of both crew members and FCT members generally increased along with increasing time delay. 2) Advanced procedure execution viewers, caution and warning tools, and communications protocols such as text messaging decreased the workload of both flight controllers and crew, and decreased the difficulty of coordinating activities. 3) Whereas crew workload ratings increased between 50 sec and 300 sec of time-delay in the Baseline configuration, workload ratings decreased (or remained flat) in the Mitigation configuration.

37 CFR 350.5 - Time.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Time. 350.5 Section 350.5... RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.5 Time. (a) Computation. To compute the due... reasons why there is good cause for the delay; (5) The justification for the amount of additional time...

37 CFR 350.5 - Time.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Time. 350.5 Section 350.5... RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.5 Time. (a) Computation. To compute the due... reasons why there is good cause for the delay; (5) The justification for the amount of additional time...

37 CFR 350.5 - Time.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Time. 350.5 Section 350.5... RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.5 Time. (a) Computation. To compute the due... reasons why there is good cause for the delay; (5) The justification for the amount of additional time...

37 CFR 350.5 - Time.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Time. 350.5 Section 350.5... RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.5 Time. (a) Computation. To compute the due... reasons why there is good cause for the delay; (5) The justification for the amount of additional time...

37 CFR 350.5 - Time.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Time. 350.5 Section 350.5... RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.5 Time. (a) Computation. To compute the due... reasons why there is good cause for the delay; (5) The justification for the amount of additional time...

Using an iPad Application to Promote Early Literacy Development in Young Children with Disabilities

ERIC Educational Resources Information Center

Chai, Zhen; Vail, Cynthia O.; Ayres, Kevin M.

2015-01-01

This investigation evaluated the effects of using an iPad application to teach young children with developmental delays to receptively identify initial phonemes through 0- to 5-s constant time delay procedures in the context of a multiple-probe design across three sets of behaviors and replicated across three students. The dependent variable was…

Delay Discounting of Video Game Players: Comparison of Time Duration Among Gamers

PubMed Central

Sprong, Matthew E.; Lloyd, Daniel P.; Cutter, Christopher J.; Printz, Destiny M.B.; Sullivan, Ryan M.; Moore, Brent A.

2017-01-01

Abstract Video game addiction or Internet game disorder, as proposed by the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition), has similar criterion characteristics to other impulse control disorders. There is limited research examining video game addiction within a behavioral economic framework using delay discounting. The current study evaluated delay-discounting patterns of money and video game play by usual weekly hours of video game play. A total of 104 participants were split into 1 of 3 groups of video game players (low, medium, and high) and were asked to complete a monetary and video game discounting procedure through an online survey. Results showed significant differences between groups within both the monetary (p = 0.003) and video game discounting procedures (p = 0.004). Additionally, a positive linear relationship was noted between the groups across both procedures. The results of the current article reinforce previous findings that more hours of video game use are associated with greater impulsivity and provide implications for future research. PMID:28118044

Delay Discounting of Video Game Players: Comparison of Time Duration Among Gamers.

PubMed

Buono, Frank D; Sprong, Matthew E; Lloyd, Daniel P; Cutter, Christopher J; Printz, Destiny M B; Sullivan, Ryan M; Moore, Brent A

2017-02-01

Video game addiction or Internet game disorder, as proposed by the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition), has similar criterion characteristics to other impulse control disorders. There is limited research examining video game addiction within a behavioral economic framework using delay discounting. The current study evaluated delay-discounting patterns of money and video game play by usual weekly hours of video game play. A total of 104 participants were split into 1 of 3 groups of video game players (low, medium, and high) and were asked to complete a monetary and video game discounting procedure through an online survey. Results showed significant differences between groups within both the monetary (p = 0.003) and video game discounting procedures (p = 0.004). Additionally, a positive linear relationship was noted between the groups across both procedures. The results of the current article reinforce previous findings that more hours of video game use are associated with greater impulsivity and provide implications for future research.

Acquisition of delayed matching in the pigeon.

PubMed

Berryman, R; Cumming, W W; Nevin, J A

1963-01-01

Pigeons were exposed to three successive matching-to-sample procedures. On a given trial, the sample (red, green or blue light) appeared on a center key; observing responses to this key produced the comparison stimuli on two side keys. Seven different experimental conditions could govern the temporal relations between the sample and comparison stimuli. In the "simultaneous" condition, the center key response was followed immediately by illumination of the side key comparison stimuli, with the center key remaining on. In "zero delay" the center key response simultaneously turned the side keys on and the center key off, while in the "variable delay" conditions, intervals of 1, 2, 4, 10, and 24 sec were interposed between the offset of the sample and the appearance of the comparison stimuli on the side keys. In all conditions, a response to the side key of matching hue produced reinforcement, while a response to the non-matching side key was followed by a blackout. In procedure I all seven experimental conditions were presented in randomly permutated order. After nine sessions of exposure (at 191 trials per session, for a total of 1719 trials) the birds gave no evidence of acquisition in any of the conditions. They were therefore transferred to Procedure II, which required them to match only in the "simultaneous" condition, with both the sample and comparison stimuli present at the same time. With the exception of one bird, all subjects acquired this performance to near 100% levels. Next, in Procedure III, they were once more exposed to presentation of all seven experimental conditions in random order. In contrast to Procedure I, they now acquired the delay performance, and were able to match effectively at delays of about 4 sec.

Delay Discounting in Lewis and Fischer 344 Rats: Steady-state and Rapid-determination Adjusting-amount Procedures

PubMed Central

Stein, Jeffrey S; Pinkston, Jonathan W; Brewer, Adam T; Francisco, Monica T; Madden, Gregory J

2012-01-01

Lewis rats have been shown to make more impulsive choices than Fischer 344 rats in discrete-trial choice procedures that arrange fixed (i.e., nontitrating) reinforcement parameters. However, nontitrating procedures yield only gross estimates of preference, as choice measures in animal subjects are rarely graded at the level of the individual subject. The present study was designed to examine potential strain differences in delay discounting using an adjusting-amount procedure, in which distributed (rather than exclusive) choice is observed due to dynamic titration of reinforcer magnitude across trials. Using a steady-state version of the adjusting-amount procedure in which delay was manipulated between experimental conditions, steeper delay discounting was observed in Lewis rats compared to Fischer 344 rats; further, delay discounting in both strains was well described by the traditional hyperbolic discounting model. However, upon partial completion of the present study, a study published elsewhere (Wilhelm & Mitchell, 2009) demonstrated no difference in delay discounting between these strains with the use of a more rapid version of the adjusting-amount procedure (i.e., in which delay is manipulated daily). Thus, following completion of the steady-state assessment in the present study, all surviving Lewis and Fischer 344 rats completed an approximation of this rapid-determination procedure in which no strain difference in delay discounting was observed. PMID:22693360

Delay discounting in Lewis and Fischer 344 rats: steady-state and rapid-determination adjusting-amount procedures.

PubMed

Stein, Jeffrey S; Pinkston, Jonathan W; Brewer, Adam T; Francisco, Monica T; Madden, Gregory J

2012-05-01

Lewis rats have been shown to make more impulsive choices than Fischer 344 rats in discrete-trial choice procedures that arrange fixed (i.e., nontitrating) reinforcement parameters. However, nontitrating procedures yield only gross estimates of preference, as choice measures in animal subjects are rarely graded at the level of the individual subject. The present study was designed to examine potential strain differences in delay discounting using an adjusting-amount procedure, in which distributed (rather than exclusive) choice is observed due to dynamic titration of reinforcer magnitude across trials. Using a steady-state version of the adjusting-amount procedure in which delay was manipulated between experimental conditions, steeper delay discounting was observed in Lewis rats compared to Fischer 344 rats; further, delay discounting in both strains was well described by the traditional hyperbolic discounting model. However, upon partial completion of the present study, a study published elsewhere (Wilhelm & Mitchell, 2009) demonstrated no difference in delay discounting between these strains with the use of a more rapid version of the adjusting-amount procedure (i.e., in which delay is manipulated daily). Thus, following completion of the steady-state assessment in the present study, all surviving Lewis and Fischer 344 rats completed an approximation of this rapid-determination procedure in which no strain difference in delay discounting was observed.

Observational and Incidental Learning by Children with Autism during Small Group Instruction

ERIC Educational Resources Information Center

Ledford, Jennifer R.; Gast, David L.; Luscre, Deanna; Ayres, Kevin M.

2008-01-01

This study evaluated the acquisition of incidental and observational information presented to 6 children with autism in a small group instructional arrangement using a constant time delay (CTD) procedure. A multiple probe design across behaviors, replicated across 6 participants, was used to evaluate the effectiveness of the CTD procedure and to…

Unequal-Arm Interferometry and Ranging in Space

NASA Technical Reports Server (NTRS)

Tinto, Massimo

2005-01-01

Space-borne interferometric gravitational wave detectors, sensitive in the low-frequency (millihertz) band, will fly in the next decade. In these detectors the spacecraft-to-spacecraft light-traveltimes will necessarily be unequal, time-varying, and (due to aberration) have different time delays on up- and down-links. By using knowledge of the inter-spacecraft light-travel-times and their time evolution it is possible to cancel in post-processing the otherwise dominant laser phase noise and obtain a variety of interferometric data combinations sensitive to gravitational radiation. This technique, which has been named Time-Delay Interferometry (TDI), can be implemented with constellations of three or more formation-flying spacecraft that coherently track each other. As an example application we consider the Laser Interferometer Space Antenna (LISA) mission and show that TDI combinations can be synthesized by properly time-shifting and linearly combining the phase measurements performed on board the three spacecraft. Since TDI exactly suppresses the laser noises when the delays coincide with the light-travel-times, we then show that TDI can also be used for estimating the time-delays needed for its implementation. This is done by performing a post-processing non-linear minimization procedure, which provides an effective, powerful, and simple way for making measurements of the inter-spacecraft light-travel-times. This processing technique, named Time-Delay Interferometric Ranging (TDIR), is highly accurate in estimating the time-delays and allows TDI to be successfully implemented without the need of a dedicated ranging subsystem.

Application of the differential decay-curve method to γ-γ fast-timing lifetime measurements

NASA Astrophysics Data System (ADS)

Petkov, P.; Régis, J.-M.; Dewald, A.; Kisyov, S.

2016-10-01

A new procedure for the analysis of delayed-coincidence lifetime experiments focused on the Fast-timing case is proposed following the approach of the Differential decay-curve method. Examples of application of the procedure on experimental data reveal its reliability for lifetimes even in the sub-nanosecond range. The procedure is expected to improve both precision/reliability and treatment of systematic errors and scarce data as well as to provide an option for cross-check with the results obtained by means of other analyzing methods.

Delay of Gratification and Delay Discounting: A Unifying Feedback Model of Delay-Related Impulsive Behavior

ERIC Educational Resources Information Center

Reynolds, Brady; Schiffbauer, Ryan

2005-01-01

Delay of Gratification (DG) and Delay Discounting (DD) represent two indices of impulsive behavior often treated as though they represent equivalent or the same underlying processes. However, there are key differences between DG and DD procedures, and between certain research findings with each procedure, that suggest they are not equivalent. In…

Improving Early Reading Skills in Young Children through an iPad App: Small-Group Instruction and Observational Learning

ERIC Educational Resources Information Center

Chai, Zhen

2017-01-01

This study evaluated the effectiveness of using a researcher-developed iPad app with a 0- to 5-s constant time delay procedure to improve phonological awareness skills of young children with mild developmental delays in a small-group arrangement in a rural public elementary school in Southwest United States. The study was conducted using a…

Real-Time Closed-Captioned Television as an Educational Tool.

ERIC Educational Resources Information Center

Block, Martin H.; Okrand, Marc

1983-01-01

Procedures used in real-time (live) television captioning are reviewed, and aspects of the captioning process, such as time delay, use of verbatim captions, targeted reading rates, ways to indicate changes in speakers, and accuracy are considered. Use of real-time captioning in closed-caption television in the classroom is noted. (CL)

Break-before-make CMOS inverter for power-efficient delay implementation.

PubMed

Puhan, Janez; Raič, Dušan; Tuma, Tadej; Bűrmen, Árpád

2014-01-01

A modified static CMOS inverter with two inputs and two outputs is proposed to reduce short-circuit current in order to increment delay and reduce power overhead where slow operation is required. The circuit is based on bidirectional delay element connected in series with the PMOS and NMOS switching transistors. It provides differences in the dynamic response so that the direct-path current in the next stage is reduced. The switching transistors are never ON at the same time. Characteristics of various delay element implementations are presented and verified by circuit simulations. Global optimization procedure is used to obtain the most power-efficient transistor sizing. The performance of the modified CMOS inverter chain is compared to standard implementation for various delays. The energy (charge) per delay is reduced up to 40%. The use of the proposed delay element is demonstrated by implementing a low-power delay line and a leading-edge detector cell.

Break-before-Make CMOS Inverter for Power-Efficient Delay Implementation

PubMed Central

Raič, Dušan

2014-01-01

A modified static CMOS inverter with two inputs and two outputs is proposed to reduce short-circuit current in order to increment delay and reduce power overhead where slow operation is required. The circuit is based on bidirectional delay element connected in series with the PMOS and NMOS switching transistors. It provides differences in the dynamic response so that the direct-path current in the next stage is reduced. The switching transistors are never ON at the same time. Characteristics of various delay element implementations are presented and verified by circuit simulations. Global optimization procedure is used to obtain the most power-efficient transistor sizing. The performance of the modified CMOS inverter chain is compared to standard implementation for various delays. The energy (charge) per delay is reduced up to 40%. The use of the proposed delay element is demonstrated by implementing a low-power delay line and a leading-edge detector cell. PMID:25538951

Assessment of Various Risk Factors for Success of Delayed and Immediate Loaded Dental Implants: A Retrospective Analysis.

PubMed

Prasant, M C; Thukral, Rishi; Kumar, Sachin; Sadrani, Sannishth M; Baxi, Harsh; Shah, Aditi

2016-10-01

Ever since its introduction in 1977, a minimum of few months of period is required for osseointegration to take place after dental implant surgery. With the passage of time and advancements in the fields of dental implant, this healing period is getting smaller and smaller. Immediate loading of dental implants is becoming a very popular procedure in the recent time. Hence, we retrospectively analyzed the various risk factors for the failure of delayed and immediate loaded dental implants. In the present study, retrospective analysis of all the patients was done who underwent dental implant surgeries either by immediate loading procedure or by delayed loading procedures. All the patients were divided broadly into two groups with one group containing patients in which delayed loaded dental implants were placed while other consisted of patients in whom immediate loaded dental implants were placed. All the patients in whom follow-up records were missing and who had past medical history of any systemic diseases were excluded from the present study. Evaluation of associated possible risk factors was done by classifying the predictable factors as primary and secondary factors. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software. Kaplan-Meier survival analyses and chi-square test were used for assessment of level of significance. In delayed and immediate group of dental implants, mean age of the patients was 54.2 and 54.8 years respectively. Statistically significant results were obtained while comparing the clinical parameters of the dental implants in both the groups while demographic parameters showed nonsignificant correlation. Significant higher risk of dental implant failure is associated with immediate loaded dental implants. Tobacco smoking, shorter implant size, and other risk factors play a significant role in predicting the success and failure of dental implants. Delayed loaded dental implant placement should be preferred as they are associated with decreased risk of implant failure.

32 CFR Appendix H to Part 275 - Procedures for Delay of Notice

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 2 2010-07-01 2010-07-01 false Procedures for Delay of Notice H Appendix H to Part 275 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE... OF 1978 Pt. 275, App. H Appendix H to Part 275—Procedures for Delay of Notice A. The customer notice...

Research and Development of Hazardous/Toxic Waste Analytical Screening Procedures. Available Field Methods for Rapid Screening of Hazardous Waste Materials at Waste Sites (Class A Poisons).

DTIC Science & Technology

1982-01-01

bromide is listed as a positive interference. Nitric oxide and nitrogen dioxide can be detected by using the Draeger nitrous fumes detector tube. A... fumes exhibit a delay from the time of exposure to the onset of symptoms. This time delay would not be conducive for a rapid field screening test. It...Dangerous when strongly heated, emits highly toxic fumes . THRESHOLD LIMIT VALUE: No information available PHYSIOLOGICAL EFFECTS: A. Intensely irritating to

Teleoperation in surgical robotics--network latency effects on surgical performance.

PubMed

Lum, Mitchell J H; Rosen, Jacob; King, Hawkeye; Friedman, Diana C W; Lendvay, Thomas S; Wright, Andrew S; Sinanan, Mika N; Hannaford, Blake

2009-01-01

A teleoperated surgical robotic system allows surgical procedures to be conducted across long distances while utilizing wired and wireless communication with a wide spectrum of performance that may affect the outcome. An open architecture portable surgical robotic system (Raven) was developed for both open and minimally invasive surgery. The system has been the subject of an intensive telesurgical experimental protocol aimed at exploring the boundaries of the system and surgeon performance during a series of field experiments in extreme environments (desert and underwater) teleportation between US, Europe, and Japan as well as lab experiments under synthetic fixed time delay. One standard task (block transfer emulating tissue manipulation) of the Fundamentals of Laparoscopic Surgery (FLS) training kit was used for the experimental protocol. Network characterization indicated a typical time delay in the range of 16-172 ms in field experiments. The results of the lab experiments showed that the completion time of the task as well as the length of the tool tip trajectory significantly increased (alpha< 0.02) as time delay increased in the range of 0-0.5 sec increased. For teleoperation with a time delay of 0.25s and 0.5s the task completion time was lengthened by a factor of 1.45 and 2.04 with respect to no time delay, whereas the length of the tools' trajectory was increased by a factor of 1.28 and 1.53 with respect to no time delay. There were no statistical differences between experienced surgeons and non-surgeons in the number of errors (block drooping) as well as the completion time and the tool tip path length at different time delays.

Measurement of oxidative metabolism of the working human muscles by near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Yücetaş, Akin; Şayli, Ömer; Karahan, Mustafa; Akin, Ata

2006-02-01

Monitoring the oxygenation of skeletal muscle tissues during rest to work transient provides valuable information about the performance of a particular tissue in adapting to aerobic glycolysis. In this paper we analyze the temporal relation of O II consumption with deoxy-hemoglobin (Hb) signals measured by functional Near Infrared Spectroscopy (fNIRS) technique during moderate isotonic forearm finger joint flexion exercise under ischemic conditions and model it with a mono exponential equation with delay. The time constants of fitting equation are questioned under two different work loads and among subjects differing in gender. Ten (6 men and 4 women) subjects performed isotonic forearm finger joint flexion exercise with two different loads. It is shown that under the same load, men and women subjects generate similar time constants and time delays. However, apparent change in time constants and time delays were observed when exercise was performed under different loads. When t-test is applied to compare the outputs for time constants between 0.41202 Watts and 0.90252 Watts, P value of 9.3445x10 -4 < 0.05 is observed which implies that the differences between the time constants are statistically significant. When the same procedure is applied for the time delay comparison, P value of 0.027<0.05 is observed which implies that also the differences between the time delays are statistically significant.

Impact on delay times and characteristics of patients undergoing primary percutaneous coronary intervention in the southern metropolitan area of Barcelona after implementation of the infarction code program.

PubMed

Gómez-Hospital, Joan Antoni; Dallaglio, Paolo Domenico; Sánchez-Salado, Jose Carlos; Ariza, Albert; Homs, Silvia; Lorente, Victoria; Ferreiro, Jose Luis; Gomez-Lara, Josep; Romaguera, Rafael; Salazar-Mendiguchía, Joel; Teruel, Luis; Cequier, Ángel

2012-10-01

A standardized protocol of emergent transfer for primary percutaneous coronary intervention for patients with ST elevation myocardial infarction, defined as the Infarction Code, was implemented in June 2009 in the Catalan regional health system. The objective of this study was to evaluate the impact of the new protocol on delay times, number of procedures and clinical characteristics compared with the previous period in the population of patients referred to our hospital. All consecutive patients undergoing primary percutaneous coronary intervention in our hospital were prospectively registered. The clinical characteristics, delay times and mortality in the follow-up of the protocol implementation period (June 2009-May 2010) were analyzed and compared with the previous year (June 2008-May 2009). During the protocol period, 514 patients were included, compared with 241 in the previous year. Age, cardiovascular risk factors, anterior myocardial infarction and procedure characteristics were similar in the 2 groups. The first medical contact to balloon time was lower in the protocol period (median time 120 min vs 88 min; P<.001). Patients in the protocol period showed a trend toward less severe disease (Killip III, rescue angioplasty). The multivariate regression analysis showed a significant association between 1-year mortality and age, Killip class ≥ III at admission, anterior infarction and 3-vessel disease. The introduction of the Infarction Code program increased the number of patients treated by primary percutaneous coronary intervention with a reduction in delay times and better clinical characteristics at presentation. Full English text available from:www.revespcardiol.org. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Teachers' generalized use of delay as a stimulus control procedure to increase language use in handicapped children.

PubMed Central

Halle, J W; Baer, D M; Spradlin, J E

1981-01-01

In Experiment 1, classroom teachers were taught to delay their offers of help in naturally occurring situations, and thereby to provide additional opportunities for language use by six moderately retarded language-delayed children. The teachers introduced this delay technique in a multiple-baseline design across the six children. As delays were used, child verbal initiations increased. Follow-up assessment showed that teachers were maintaining greater than baseline levels of the delay technique after 10 weeks. Experiment 2 replicated the findings of Experiment 1, and included a more thorough maintenance assessment, while focusing on teachers' generalization of the delay technique. Teachers were found to generalize their use of delay to 56% of their monitored untaught opportunities. The two experiments show that (a) the delay technique is quick to teach and simple to implement, (b) delays do provide opportunities for children to initiate, (c) teachers can generalize their use of delay to novel self-selected situations, and (d) teachers can maintain their use of delays over time. PMID:6460019

A comparison of pecking generated by serial, delay, and trace autoshaping procedures1

PubMed Central

Newlin, Robert J.; LoLordo, Vincent M.

1976-01-01

Pigeons were exposed to serial, delay, and trace autoshaping procedures. In Experiment I, all conditioned stimuli (CSs) were changes in illumination of the response key. The number of trials to acquisition of the keypeck increased from serial, to 4-sec delay, 8-sec delay, and 8-sec trace procedures, in that order. In Experiment II, which used a longer intertrial interval, trials to criterion increased from 8-sec delay, to 28-sec delay, 8-sec trace, and 28-sec trace procedures, in that order. In Experiment III, two groups received serial procedures in which the first CS was either a tone or a houselight, and the second was a keylight. The tone group acquired the key peck more rapidly than the houselight group. Early in conditioning in these experiments, and when the conditioned stimulus was a change in the keylight, there was a short latency to the onset of pecking and pecking was directed at the CS. After extensive conditioning, or when the CS was relatively diffuse, pecking still occurred, but had a longer latency and was not reliably directed toward the conditioned stimulus. PMID:16811907

Delay of Gratification, Delay Discounting and their Associations with Age, Episodic Future Thinking, and Future Time Perspective.

PubMed

Göllner, Lars M; Ballhausen, Nicola; Kliegel, Matthias; Forstmeier, Simon

2017-01-01

The delay of gratification (DoG) in children is widely investigated with an experimental procedure originally called the "marshmallow test," whereas the studies on self-regulation (SR) in adolescents and adults usually use self-report questionnaires. Delay discounting (DD) measures simplify the DoG procedure and focus on monetary rewards. The aim of this study was to investigate age differences in DoG and DD from childhood to old age using a test that is suitable for both children and adults. Furthermore, investigations were conducted on the association between DoG/DD and two future orientation constructs [future time perspective (FTP) and episodic future thinking (EFT)] as well as age differences in these constructs. Participants from five age groups (9-14, 18-25, 35-55, 65-80, 80+) participated in the study ( N = 96). While we found no age difference for DoG, DD was the lowest [i.e., self-control (SC) was the highest] in young/middle adults; however, it was the highest (i.e., SC was the lowest) in children and old/oldest adults. Furthermore, we found significant age differences for DD and FTP. As predicted, there were strong correlations between DoG and FTP and between DD and FTP, but not between DoG/DD and EFT. These results indicate that age differences in SR vary across the measures used. Individuals who generally think and act in a future-oriented manner have a stronger ability to delay gratification.

A Fast MAC-Layer Handover for an IEEE 802.16e-Based WMAN

NASA Astrophysics Data System (ADS)

Ray, Sayan K.; Pawlikowski, Krzysztof; Sirisena, Harsha

We propose a modification of the IEEE 802.16e hard handover (HHO) procedure, which significantly reduces the handover latency constraint of the original HHO procedure in IEEE 802.16e networks. It allows a better handling of the delay-sensitive traffic by avoiding unnecessary time-consuming scanning and synchronization activity as well as simplifies the network re-entry procedure. With the help of the backhaul network, it reduces the number of control messages in the original handover policy, making the handover latency acceptable also for real-time streaming traffic. Preliminary performance evaluation studies show that the modified handover procedure is able to reduce the total handover latency by about 50%.

Management of the treatment delay in symptomatic carotid artery stenosis.

PubMed

Stiehm, Markus; Björses, Katarina; Kremer, Christine

2013-01-01

Saving time to intervention is crucial in patients with symptomatic carotid artery stenosis (SCAS). We introduced a fast-track protocol (FTP). Time frames from the onset of symptoms to intervention before and after the introduction of an FTP were analyzed. SCAS patients (403 patients/405 procedures) were evaluated according to whether surgery was performed before (group 1) or after (group 2) the introduction of the FTP. Time frames to surgery, causes of delay and frequency of recurrent events are reported. The median time delay decreased from 17 to 12 days (p<0.001), but time to ultrasound examination remained unchanged. Surgery was within 2 weeks in 41% in group 1 and in 57% in group 2 (p=0.001). Of 181 (30%) patients treated according to the FTP, 54 were operated within 7 days (median), and 80% had the intervention within 2 weeks. Time to surgery decreased significantly after the introduction of the FTP. © 2013 S. Karger AG, Basel.

Extracting the time scales of conformational dynamics from single-molecule single-photon fluorescence statistics.

PubMed

Shang, Jianyuan; Geva, Eitan

2007-04-26

The quenching rate of a fluorophore attached to a macromolecule can be rather sensitive to its conformational state. The decay of the corresponding fluorescence lifetime autocorrelation function can therefore provide unique information on the time scales of conformational dynamics. The conventional way of measuring the fluorescence lifetime autocorrelation function involves evaluating it from the distribution of delay times between photoexcitation and photon emission. However, the time resolution of this procedure is limited by the time window required for collecting enough photons in order to establish this distribution with sufficient signal-to-noise ratio. Yang and Xie have recently proposed an approach for improving the time resolution, which is based on the argument that the autocorrelation function of the delay time between photoexcitation and photon emission is proportional to the autocorrelation function of the square of the fluorescence lifetime [Yang, H.; Xie, X. S. J. Chem. Phys. 2002, 117, 10965]. In this paper, we show that the delay-time autocorrelation function is equal to the autocorrelation function of the square of the fluorescence lifetime divided by the autocorrelation function of the fluorescence lifetime. We examine the conditions under which the delay-time autocorrelation function is approximately proportional to the autocorrelation function of the square of the fluorescence lifetime. We also investigate the correlation between the decay of the delay-time autocorrelation function and the time scales of conformational dynamics. The results are demonstrated via applications to a two-state model and an off-lattice model of a polypeptide.

National Airspace System Delay Estimation Using Weather Weighted Traffic Counts

NASA Technical Reports Server (NTRS)

Chatterji, Gano B.; Sridhar, Banavar

2004-01-01

Assessment of National Airspace System performance, which is usually measured in terms of delays resulting from the application of traffic flow management initiatives in response to weather conditions, volume, equipment outages and runway conditions, is needed both for guiding flow control decisions during the day of operations and for post operations analysis. Comparison of the actual delay, resulting from the traffic flow management initiatives, with the expected delay, based on traffic demand and other conditions, provides the assessment of the National Airspace System performance. This paper provides a method for estimating delay using the expected traffic demand and weather. In order to identify the cause of delays, 517 days of National Airspace System delay data reported by the Federal Aviation Administration s Operations Network were analyzed. This analysis shows that weather is the most important causal factor for delays followed by equipment and runway delays. Guided by these results, the concept of weather weighted traffic counts as a measure of system delay is described. Examples are given to show the variation of these counts as a function of time of the day. The various datasets, consisting of aircraft position data, enroute severe weather data, surface wind speed and visibility data, reported delay data and number of aircraft handled by the Centers data, and their sources are described. The procedure for selecting reference days on which traffic was minimally impacted by weather is described. Different traffic demand on each reference day of the week, determined by analysis of 42 days of traffic and delay data, was used as the expected traffic demand for each day of the week. Next, the method for computing the weather weighted traffic counts using the expected traffic demand, derived from reference days, and the expanded regions around severe weather cells is discussed. It is shown via a numerical example that this approach improves the dynamic range of the weather weighted traffic counts considerably. Time histories of these new weather weighted traffic counts are used for synthesizing two statistical features, six histogram features and six time domain features. In addition to these enroute weather features, two surface weather features of number of major airports in the United States with high mean winds and low mean visibility are also described. A least squares procedure for establishing a functional relation between the features, using combinations of these features, and system delays is explored using 36 days of data. Best correlations between the estimated delays using the functional relation and the actual delays provided by the Operations Network are obtained with two different combinations of features: 1) six time domain features of weather weighted traffic counts plus two surface weather features, and 2) six histogram features and mean of weather weighted traffic counts along with the two surface weather features. Correlation coefficient values of 0.73 and 0.83 were found in these two instances.

Suitable closure for post-duodenal endoscopic resection taking medical costs into consideration

PubMed Central

Mori, Hirohito; Ayaki, Maki; Kobara, Hideki; Fujihara, Shintaro; Nishiyama, Noriko; Matsunaga, Tae; Yachida, Tatsuo; Masaki, Tsutomu

2015-01-01

AIM: To compare closure methods, closure times and medical costs between two groups of patients who had post-endoscopic resection (ER) artificial ulcer floor closures. METHODS: Nineteen patients with duodenal adenoma, early duodenal cancer, and subepithelial tumors that received ER between September 2009 and September 2014 at Kagawa University Hospital and Ehime Rosai Hospital, an affiliated hospital of Kagawa University, were included in the study. We retrospectively compared two groups of patients who received post-ER artificial ulcer floor closure: the conventional clip group vs the over-the-scope clip (OTSC) group. Delayed bleeding, procedure time of closure, delayed perforation, total number of conventional clips and OTSCs and medical costs were analyzed. RESULTS: Although we observed delayed bleeding in three patients in the conventional clip group, we observed no delayed bleeding in the OTSC group (P = 0.049). We did not observe perforation in either group. The mean procedure times for ulcer closure were 33.26 ± 12.57 min and 9.71 ± 2.92 min, respectively (P = 0.0001). The resection diameters were 18.8 ± 1.30 mm and 22.9 ± 1.21 mm for the conventional clip group and the OTSC group, respectively, with significant difference (P = 0.039). As for medical costs, the costs of all conventional clips were USD $1257 and the costs of OTSCs were $7850 (P = 0.005). If the post-ER ulcer is under 20 mm in diameter, a conventional clip closure may be more suitable with regard to the prevention of delayed perforation and to medical costs. CONCLUSION: If the post-ER ulcer is over 20 mm, the OTSC closure should be selected with regard to safety and reliable closure even if there are high medical costs. PMID:25954101

Suitable closure for post-duodenal endoscopic resection taking medical costs into consideration.

PubMed

Mori, Hirohito; Ayaki, Maki; Kobara, Hideki; Fujihara, Shintaro; Nishiyama, Noriko; Matsunaga, Tae; Yachida, Tatsuo; Masaki, Tsutomu

2015-05-07

To compare closure methods, closure times and medical costs between two groups of patients who had post-endoscopic resection (ER) artificial ulcer floor closures. Nineteen patients with duodenal adenoma, early duodenal cancer, and subepithelial tumors that received ER between September 2009 and September 2014 at Kagawa University Hospital and Ehime Rosai Hospital, an affiliated hospital of Kagawa University, were included in the study. We retrospectively compared two groups of patients who received post-ER artificial ulcer floor closure: the conventional clip group vs the over-the-scope clip (OTSC) group. Delayed bleeding, procedure time of closure, delayed perforation, total number of conventional clips and OTSCs and medical costs were analyzed. Although we observed delayed bleeding in three patients in the conventional clip group, we observed no delayed bleeding in the OTSC group (P = 0.049). We did not observe perforation in either group. The mean procedure times for ulcer closure were 33.26 ± 12.57 min and 9.71 ± 2.92 min, respectively (P = 0.0001). The resection diameters were 18.8 ± 1.30 mm and 22.9 ± 1.21 mm for the conventional clip group and the OTSC group, respectively, with significant difference (P = 0.039). As for medical costs, the costs of all conventional clips were USD $1257 and the costs of OTSCs were $7850 (P = 0.005). If the post-ER ulcer is under 20 mm in diameter, a conventional clip closure may be more suitable with regard to the prevention of delayed perforation and to medical costs. If the post-ER ulcer is over 20 mm, the OTSC closure should be selected with regard to safety and reliable closure even if there are high medical costs.

Decreasing Errors in Reading-Related Matching to Sample Using a Delayed-Sample Procedure

ERIC Educational Resources Information Center

Doughty, Adam H.; Saunders, Kathryn J.

2009-01-01

Two men with intellectual disabilities initially demonstrated intermediate accuracy in two-choice matching-to-sample (MTS) procedures. A printed-letter identity MTS procedure was used with 1 participant, and a spoken-to-printed-word MTS procedure was used with the other participant. Errors decreased substantially under a delayed-sample procedure,…

Is early cord clamping, delayed cord clamping or cord milking best?

PubMed

Vatansever, Binay; Demirel, Gamze; Ciler Eren, Elif; Erel, Ozcan; Neselioglu, Salim; Karavar, Hande Nur; Gundogdu, Semra; Ulfer, Gozde; Bahadir, Selcen; Tastekin, Ayhan

2018-04-01

To compare the antioxidant status of three cord clamping procedures (early clamping, delayed clamping and milking) by analyzing the thiol-disulfide balance. This randomized controlled study enrolled 189 term infants who were divided into three groups according to the cord clamping procedure: early clamping, delayed clamping and milking. Blood samples were collected from the umbilical arteries immediately after clamping, and the thiol/disulfide homeostasis was analyzed. The native and total thiol levels were significantly (p < .05) lower in the early cord clamping group compared with the other two groups. The disulfide/total thiol ratio was significantly (p = .026) lower in the delayed cord clamping and milking groups compared with the early clamping groups. Early cord clamping causes the production of more disulfide bonds and lower thiol levels, indicating that oxidation reactions are increased in the early cord clamping procedure compared with the delayed cord clamping and milking procedures. The oxidant capacity is greater with early cord clamping than with delayed clamping or cord milking. Delayed cord clamping or milking are beneficial in neonatal care, and we suggest that they be performed routinely in all deliveries.

Delayed benefit of naps on motor learning in preschool children.

PubMed

Desrochers, Phillip C; Kurdziel, Laura B F; Spencer, Rebecca M C

2016-03-01

Sleep benefits memory consolidation across a variety of domains in young adults. However, while declarative memories benefit from sleep in young children, such improvements are not consistently seen for procedural skill learning. Here we examined whether performance improvements on a procedural task, although not immediately observed, are evident after a longer delay when augmented by overnight sleep (24 h after learning). We trained 47 children, aged 33-71 months, on a serial reaction time task and, using a within-subject design, evaluated performance at three time points: immediately after learning, after a daytime nap (nap condition) or equivalent wake opportunity (wake condition), and 24 h after learning. Consistent with previous studies, performance improvements following the nap did not differ from performance improvements following an equivalent interval spent awake. However, significant benefits of the nap were found when performance was assessed 24 h after learning. This research demonstrates that motor skill learning is benefited by sleep, but that this benefit is only evident after an extended period of time.

Improved pupil dilation with medication-soaked pledget sponges.

PubMed

Weddle, Celeste; Thomas, Nikki; Dienemann, Jacqueline

2013-08-01

Use of multiple preoperative drops for pupil dilation has been shown to be inexact, to delay surgery, and to cause dissatisfaction among perioperative personnel. This article reports on an evidence-based, quality improvement project to locate and appraise research on improved effectiveness and efficiency of mydriasis (ie, pupillary dilation), and the subsequent implementation of a pledget-sponge procedure for pupil dilation at one ambulatory surgery center. Project leaders used an evidence-based practice model to assess the problem, research options for improvement, define goals, and implement a pilot project to test the new dilation technique. Outcomes from the pilot project showed a reduced number of delays caused by poor pupil dilation and a decrease in procedure turnover time. The project team solicited informal feedback from preoperative nurses, which reflected increased satisfaction in preparing patients for cataract procedures. After facility administrators and surgeons accepted the procedure change, it was adopted for preoperative use for all patients undergoing cataract surgery at the ambulatory surgery center. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

Data Assimilation by delay-coordinate nudging

NASA Astrophysics Data System (ADS)

Pazo, Diego; Lopez, Juan Manuel; Carrassi, Alberto

2016-04-01

A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A connection between the optimal delay and the dominant Lyapunov exponent of the dynamics is found based on heuristic arguments and is confirmed by the numerical results, providing a guideline for the practical implementation of the algorithm. Delay-coordinate nudging preserves the easiness of implementation, the intuitive functioning and the reduced computational cost of the standard nudging, making it a potential alternative especially in the field of seasonal-to-decadal predictions with large Earth system models that limit the use of more sophisticated data assimilation procedures.

Molindone: effects in pigeons responding under conditional discrimination tasks.

PubMed

Picker, M J; Cleary, J P; Berens, K; Oliveto, A H; Dykstra, L A

1989-02-01

Pigeons were trained to respond under three conditional discrimination procedures; 1) a fixed-consecutive-number procedure with (FCN 8-SD) and without (FCN 8) an added external discriminative stimulus, 2) a delayed matching-to-sample (DMTS) procedure using 0-sec, 2-sec and 8-sec delay intervals, and 3) a repeated acquisition of behavioral chains (RA) procedure using a four-link response chain with three stimulus keys. The atypical neuroleptic agent molindone decreased accuracy under the FCN 8 at doses that had no effect on accuracy under the FCN 8-SD. Under the DMTS procedure, molindone-induced decreases in accuracy were directly related to the delay interval, with the largest relative decrements obtained at the 8-sec delay and the smallest at the 0-sec delay. Under the RA procedure, molindone decreased accuracy at doses that had little or no effect on the number of correct responses emitted. Relative to control values, molindone-induced decreases in accuracy were smallest under the DMTS and FCN 8-SD procedures and largest under the FCN 8 and RA procedures. The differential effects obtained with molindone under each of these procedures illustrate the need to employ a variety of assays when determining the behavioral actions of neuroleptics. In addition, this battery of behavioral tests may provide a useful tool for assessing the different neurochemical actions of neuroleptic compounds.

Delayed grafting for banked skin graft in lymph node flap transfer.

PubMed

Ciudad, Pedro; Date, Shivprasad; Orfaniotis, Georgios; Dower, Rory; Nicoli, Fabio; Maruccia, Michele; Lin, Shu-Ping; Chuang, Chu-Yi; Chuang, Tsan-Yu; Wang, Gou-Jen; Chen, Hung-Chi

2017-02-01

Over the last decade, lymph node flap (LNF) transfer has turned out to be an effective method in the management of lymphoedema of extremities. Most of the time, the pockets created for LNF cannot be closed primarily and need to be resurfaced with split thickness skin grafts. Partial graft loss was frequently noted in these cases. The need to prevent graft loss on these iatrogenic wounds made us explore the possibility of attempting delayed skin grafting. We have herein reported our experience with delayed grafting with autologous banked split skin grafts in cases of LNF transfer for lymphoedema of the extremities. Ten patients with International Society of Lymphology stage II-III lymphoedema of upper or lower extremity were included in this study over an 8-month period. All patients were thoroughly evaluated and subjected to lymph node flap transfer. The split skin graft was harvested and banked at the donor site, avoiding immediate resurfacing over the flap. The same was carried out in an aseptic manner as a bedside procedure after confirming flap viability and allowing flap swelling to subside. Patients were followed up to evaluate long-term outcomes. Flap survival was 100%. Successful delayed skin grafting was done between the 4th and 6th post-operative day as a bedside procedure under local anaesthesia. The split thickness skin grafts (STSG) takes more than 97%. One patient needed additional medications during the bedside procedure. All patients had minimal post-operative pain and skin graft requirement. The patients were also reported to be satisfied with the final aesthetic results. There were no complications related to either the skin grafts or donor sites during the entire period of follow-up. Delayed split skin grafting is a reliable method of resurfacing lymph node flaps and has been shown to reduce the possibility of flap complications as well as the operative time and costs. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Design of polynomial fuzzy observer-controller for nonlinear systems with state delay: sum of squares approach

NASA Astrophysics Data System (ADS)

Gassara, H.; El Hajjaji, A.; Chaabane, M.

2017-07-01

This paper investigates the problem of observer-based control for two classes of polynomial fuzzy systems with time-varying delay. The first class concerns a special case where the polynomial matrices do not depend on the estimated state variables. The second one is the general case where the polynomial matrices could depend on unmeasurable system states that will be estimated. For the last case, two design procedures are proposed. The first one gives the polynomial fuzzy controller and observer gains in two steps. In the second procedure, the designed gains are obtained using a single-step approach to overcome the drawback of a two-step procedure. The obtained conditions are presented in terms of sum of squares (SOS) which can be solved via the SOSTOOLS and a semi-definite program solver. Illustrative examples show the validity and applicability of the proposed results.

Monaural Sound Localization Based on Reflective Structure and Homomorphic Deconvolution

PubMed Central

Park, Yeonseok; Choi, Anthony

2017-01-01

The asymmetric structure around the receiver provides a particular time delay for the specific incoming propagation. This paper designs a monaural sound localization system based on the reflective structure around the microphone. The reflective plates are placed to present the direction-wise time delay, which is naturally processed by convolutional operation with a sound source. The received signal is separated for estimating the dominant time delay by using homomorphic deconvolution, which utilizes the real cepstrum and inverse cepstrum sequentially to derive the propagation response’s autocorrelation. Once the localization system accurately estimates the information, the time delay model computes the corresponding reflection for localization. Because of the structure limitation, two stages of the localization process perform the estimation procedure as range and angle. The software toolchain from propagation physics and algorithm simulation realizes the optimal 3D-printed structure. The acoustic experiments in the anechoic chamber denote that 79.0% of the study range data from the isotropic signal is properly detected by the response value, and 87.5% of the specific direction data from the study range signal is properly estimated by the response time. The product of both rates shows the overall hit rate to be 69.1%. PMID:28946625

Tolerable hearing-aid delays: IV. effects on subjective disturbance during speech production by hearing-impaired subjects.

PubMed

Stone, Michael A; Moore, Brian C J

2005-04-01

We assessed the effects of time delay in a hearing aid on subjective disturbance and reading rates while the user of the aid was speaking, using hearing-impaired subjects and real-time processing. The time delay was constant across frequency. A digital signal processor was programmed as a four-channel, fast-acting, wide-dynamic-range compression hearing aid. One of four delays could be selected on the aid to produce a total delay of 13, 21, 30, or 40 msec between microphone and receiver. Twenty-five subjects, mostly with near-symmetric hearing impairment of cochlear origin, were fitted bilaterally with behind-the-ear aids connected to the processor. The aids were programmed with insertion gains prescribed by the CAMEQ loudness equalization procedure for each subject and ear. Subjects were asked to read aloud from scripts: speech production rates were measured and subjective ratings of the disturbance of the delay were obtained. Subjects required some training to recognize the effects of the delay to rate it consistently. Subjective disturbance increased progressively with increasing delay and was a nonmonotonic function of low-frequency hearing loss. Subjects with mild or severe low-frequency hearing loss were generally less disturbed by the delay than those with moderate loss. Disturbance ratings tended to decrease over successive tests. Word production rates were not significantly affected by delay over the range of delays tested. The results follow a pattern similar to those presented in , obtained using a simulation of hearing loss and normally hearing subjects, except for the nonmonotonic variation of disturbance with low-frequency hearing loss. We hypothesize that disturbance is maximal when the levels in the ear canal of the low-frequency components are similar for the unaided and aided sounds. A rating of 3, which is probably just acceptable, was obtained for delays ranging from 14 to 30 msec, depending on the hearing loss. Some acclimatization to the subjective disturbance occurred over a time scale of about 1 hour.

Stimuli inevitably generated by behavior that avoids electric shock are inherently reinforcing.

PubMed Central

Dinsmoor, J A

2001-01-01

A molecular analysis based on the termination of stimuli that are positively correlated with shock and the production of stimuli that are negatively correlated with shock provides a parsimonious count for both traditional discrete-trial avoidance behavior and the data derived from more recent free-operant procedures. The necessary stimuli are provided by the intrinsic feedback generated by the subject's behavior, in addition to those presented by the experimenter. Moreover, all data compatible with the molar principle of shock-frequency reduction as reinforcement are also compatible with a delay-of-shock gradient, but some data compatible with the delay gradient are not compatible with frequency reduction. The delay gradient corresponds to functions relating magnitude of behavioral effect to the time between conditional and unconditional stimuli, the time between conditioned and primary reinforcers, and the time between responses and positive reinforcers. PMID:11453621

The dynamics and control of large flexible space structures X, part 1

NASA Technical Reports Server (NTRS)

Bainum, Peter M.; Reddy, A. S. S. R.; Li, Feiyue; Diarra, Cheick M.

1987-01-01

The effect of delay in the control system input on the stability of a continuously acting controller which is designed without considering the delay is studied. The stability analysis of a second order plant is studied analytically and verified numerically. For this example it is found that the system becomes unstable for a delay which is equivalent to only 16 percent of its natural period of motion. It is also observed that even a small amount of natural damping in the system can increase the amount of delay that can be tolerated before the onset of instability. The delay problem is formulated in the discrete time domain and an analysis procedure suggested. The maximum principle from optimal control theory is applied to minimize the time required for the slewing of a general rigid spacecraft. The slewing motion need not be restricted to a single axis maneuver. The minimum slewing time is calculated based on a quasi-linearization algorithm for the resulting two point boundary value problem. Numerical examples based on the rigidized in-orbit model of the SCOLE also include the more general reflector line-of-sight slewing maneuvers.

A Discounting Framework for Choice With Delayed and Probabilistic Rewards

PubMed Central

Green, Leonard; Myerson, Joel

2005-01-01

When choosing between delayed or uncertain outcomes, individuals discount the value of such outcomes on the basis of the expected time to or the likelihood of their occurrence. In an integrative review of the expanding experimental literature on discounting, the authors show that although the same form of hyperbola-like function describes discounting of both delayed and probabilistic outcomes, a variety of recent findings are inconsistent with a single-process account. The authors also review studies that compare discounting in different populations and discuss the theoretical and practical implications of the findings. The present effort illustrates the value of studying choice involving both delayed and probabilistic outcomes within a general discounting framework that uses similar experimental procedures and a common analytical approach. PMID:15367080

Amphetamine increases schedule-induced drinking reduced by negative punishment procedures.

PubMed

Pérez-Padilla, Angeles; Pellón, Ricardo

2003-05-01

d-Amphetamine has been reported to increase schedule-induced drinking punished by lick-dependent signalled delays in food delivery. This might reflect a drug-behaviour interaction dependent on the type of punisher, because no such effect has been found when drinking was reduced by lick-contingent electric shocks. However, the anti-punishment effect of amphetamine could be mediated by other behavioural processes, such as a loss of discriminative control or an increase in the value of delayed reinforcers. To test the effects of d-amphetamine on the acquisition and maintenance of schedule-induced drinking reduced by unsignalled delays in food delivery. Rats received 10-s unsignalled delays initiated by each lick after polydipsia was induced by a fixed-time 30-s food reinforcement schedule or from the outset of the experiment. Yoked-control rats received these same delays but independently of their own behaviour. d-Amphetamine (0.1-3.0 mg/kg) was then tested IP. d-Amphetamine dose-dependently increased and then decreased punished schedule-induced drinking. The drug led to dose-dependent reductions when the delays were not contingent or when they were applied from the outset of training. These results support the contention that d-amphetamine has an increasing effect on schedule-induced drinking that has been previously reduced by a negative punishment procedure. This effect cannot be attributed to other potentially involved processes, and therefore support the idea that drug effects on punished behaviour depend on punishment being delays in food or shock deliveries.

Effects of environmental and pharmacological manipulations on a novel delayed nonmatching-to-sample 'working memory' procedure in unrestrained rhesus monkeys.

PubMed

Hutsell, Blake A; Banks, Matthew L

2015-08-15

Working memory is a domain of 'executive function.' Delayed nonmatching-to-sample (DNMTS) procedures are commonly used to examine working memory in both human laboratory and preclinical studies. The aim was to develop an automated DNMTS procedure maintained by food pellets in rhesus monkeys using a touch-sensitive screen attached to the housing chamber. Specifically, the DNMTS procedure was a 2-stimulus, 2-choice recognition memory task employing unidimensional discriminative stimuli and randomized delay interval presentations. DNMTS maintained a delay-dependent decrease in discriminability that was independent of the retention interval distribution. Eliminating reinforcer availability during a single delay session or providing food pellets before the session did not systematically alter accuracy, but did reduce total choices. Increasing the intertrial interval enhanced accuracy at short delays. Acute Δ(9)-THC pretreatment produced delay interval-dependent changes in the forgetting function at doses that did not alter total choices. Acute methylphenidate pretreatment only decreased total choices. All monkeys were trained to perform NMTS at the 1s training delay within 60 days of initiating operant touch training. Furthermore, forgetting functions were reliably delay interval-dependent and stable over the experimental period (∼6 months). Consistent with previous studies, increasing the intertrial interval improved DNMTS performance, whereas Δ(9)-THC disrupted DNMTS performance independent of changes in total choices. Overall, the touchscreen-based DNMTS procedure described provides an efficient method for training and testing experimental manipulations on working memory in unrestrained rhesus monkeys. Copyright © 2015 Elsevier B.V. All rights reserved.

Scopolamine Effects Under a Titrating-Delayed-Nonmatching-to-Position Procedure

ERIC Educational Resources Information Center

Porritt, M.; Poling, A.

2008-01-01

In a study of working memory, the performance of rats under titrating-delayed-nonmatching- to-position (TDNMTP) procedures was examined. Overall accuracy and the number of trials completed were inversely related to titration value, whereas the highest delay attained was directly related to titration value. When given intraperitoneally,…

Time dependence of the pH of rain

Treesearch

John A. Kadlecek; Volkar A. Mohnen

1976-01-01

Standard procedures for determining the pH of rain samples usually involve substantial delays from the time of rainfall to the time of analysis. This assumes that no change in pH occurs during the storage period. We have found that this is not always true. We have determined that individual rain water samples possess a time dependent pH which can be correlated with the...

Feasibility of using administrative data for identifying medical reasons to delay hip fracture surgery: a Canadian database study.

PubMed

Guy, Pierre; Sheehan, Katie J; Morin, Suzanne N; Waddell, James; Dunbar, Michael; Harvey, Edward; Sirett, Susan; Sobolev, Boris; Kuramoto, Lisa; Tang, Michael

2017-10-05

Failure to account for medically necessary delays may lead to an underestimation of early surgery benefits. This study investigated the feasibility of using administrative data to identify the National Institute for Health and Care Excellence (NICE) 124 guideline list of conditions that appropriately delay hip fracture surgery. We assembled a list of diagnosis and procedure codes to reflect the NICE 124 conditions. The list was reviewed and updated by an advanced clinical coder. The list was refined by five clinical experts. We then screened Canadian Institute for Health Information discharge abstracts for 153 918 patients surgically treated for a non-pathological first hip fracture between 1 January 2004 and 31 December 2012 for diagnosis codes present on admission and procedure codes that antedated hip fracture surgery. We classified abstracts as having medical reasons for delaying surgery based on the presence of these codes. In total, 10 237 (6.7%; 95% CI 6.5% to 6.8%) patients had diagnostic and procedure codes indicating medical reasons for delay. The most common reasons for medical delay were exacerbation of a chronic chest condition (35.9%) and acute chest infection (23.2%). The proportion of patients with reasons for medical delays increased with time from admission to surgery: 3.9% (95% CI 3.6% to 4.1%) for same day surgery; 4.7% (95% CI 4.5% to 4.8%) for surgery 1 day after admission; 7.1% (95% CI 6.9% to 7.4%) for surgery 2 days after admission; and 15.5% (95% CI 15.1% to 16.0%) for surgery more than 2 days after admission. The trend was seen for admissions on weekday working hours, weekday after hours and on weekends. Administrative data can be considered to identify conditions that appropriately delay hip fracture surgery. Accounting for medically necessary delays can improve estimates of the effectiveness of early surgery. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Movement Suppression Time-Out for Undesirable Behavior in Psychotic and Severely Developmentally Delayed Children.

ERIC Educational Resources Information Center

Rolider, Ahmos; Van Houten, Ron

1985-01-01

Effects of a movement suppression time-out, which involved punishing any movements or verbalization while a client is in the time-out area, were evaluated in four experiments. The procedure produced a larger reduction in the target behavior in all three children and effectiveness was explained in terms of suppression of self-stimulation during…

Damage Control Orthopedics Management as Vital Procedure in Elderly Patients with Femoral Neck Fractures Complicated with Chronic Renal Failure: A Retrospective Cohort Study

PubMed Central

Dong, Chenhui; Wang, Yunjiao; Wang, Ziming; Wang, Yu; Wu, Siyu; Du, Quanyin; Wang, Aimin

2016-01-01

Background Chronic renal failure (CRF) predisposes to hip fractures in elderly patients, with high subsequent mortality. Selection and timing of the surgical procedure of such patients is a serious challenge. Many clinicians believe in earlier surgery as preferable and providing better outcomes. Damage control orthopedics (DCO) aids to adjust and optimize the overall condition of patients. Methods In 32 patients with femoral neck fractures complicated with CRF, we evaluated how the timing of the surgery determines the mortality rates if the DCO approach is applied. Preoperative ASA grading, POSSUM score, P-POSSUM score and DCO were carried out. Based on the assessment, timing of the surgery was ascertained. Results Of a total of 32 patients, twenty-nine patients were accepted for either early (< 48 hours; n = 18) or delayed (3–10 days; n = 10) surgery. Hip arthroplasty (total hip arthroplasty and hemiarthroplasty) was the principal surgery option. All patients survived operation and were followed up postoperatively with the average time of 30 days. Postoperative complications tended to occur at higher rates in the early vs. delayed surgery group (7/18 vs. 5/10). During follow up, a total of 3 patients died in both groups (2/18 in the early surgery and 1/10 in the delayed surgery group), mostly from multi-organ failures and acute respiratory distress syndrome. There was no significant difference in complication rates and Harris hip score between both groups. Conclusion In patients with femoral neck fracture complicated with CRF, delaying the surgery for several days does not increase the incidence of postoperative adverse events. PMID:27149117

Effectiveness of closure of public places with time delay in disease control.

PubMed

Wang, Zhenggang; Szeto, Kwok Yip; Leung, Frederick Chi-Ching

2008-08-25

A theoretical basis for the evaluation of the effciency of quarantine measure is developed in a SIR model with time delay. In this model, the effectiveness of the closure of public places such as schools in disease control, modeled as a high degree node in a social network, is evaluated by considering the effect of the time delay in the identification of the infected. In the context of the SIR model, the relation between the number of infectious individuals who are identified with time delay and then quarantined and those who are not identified and continue spreading the virus are investigated numerically. The social network for the simulation is modeled by a scale free network. Closure measures are applied to those infected nodes with high degrees. The effectiveness of the measure can be controlled by the present value of the critical degree K(C): only those nodes with degree higher than K(C) will be quarantined. The cost C(Q) incurred for the closure measure is assumed to be proportional to the total links rendered inactive as a result of the measure, and generally decreases with K(C), while the medical cost C(Q) incurred for virus spreading increases with K(C). The total social cost (C(M) + C(Q)) will have a minimum at a critical K(*), which depends on the ratio of medical cost coeffcient alpha(M) and closure cost coeffcient alpha(Q). Our simulation results demonstrate a mathematical procedure to evaluate the effciency of quarantine measure. Although the numerical work is based on a scale free network, the procedure can be readily generalized and applied to a more realistic social network to determine the proper closure measure in future epidemics.

Delay compensation in integrated communication and control systems. I - Conceptual development and analysis

NASA Technical Reports Server (NTRS)

Luck, Rogelio; Ray, Asok

1990-01-01

A procedure for compensating for the effects of distributed network-induced delays in integrated communication and control systems (ICCS) is proposed. The problem of analyzing systems with time-varying and possibly stochastic delays could be circumvented by use of a deterministic observer which is designed to perform under certain restrictive but realistic assumptions. The proposed delay-compensation algorithm is based on a deterministic state estimator and a linear state-variable-feedback control law. The deterministic observer can be replaced by a stochastic observer without any structural modifications of the delay compensation algorithm. However, if a feedforward-feedback control law is chosen instead of the state-variable feedback control law, the observer must be modified as a conventional nondelayed system would be. Under these circumstances, the delay compensation algorithm would be accordingly changed. The separation principle of the classical Luenberger observer holds true for the proposed delay compensator. The algorithm is suitable for ICCS in advanced aircraft, spacecraft, manufacturing automation, and chemical process applications.

Delay of Gratification, Delay Discounting and their Associations with Age, Episodic Future Thinking, and Future Time Perspective

PubMed Central

Göllner, Lars M.; Ballhausen, Nicola; Kliegel, Matthias; Forstmeier, Simon

2018-01-01

The delay of gratification (DoG) in children is widely investigated with an experimental procedure originally called the “marshmallow test,” whereas the studies on self-regulation (SR) in adolescents and adults usually use self-report questionnaires. Delay discounting (DD) measures simplify the DoG procedure and focus on monetary rewards. The aim of this study was to investigate age differences in DoG and DD from childhood to old age using a test that is suitable for both children and adults. Furthermore, investigations were conducted on the association between DoG/DD and two future orientation constructs [future time perspective (FTP) and episodic future thinking (EFT)] as well as age differences in these constructs. Participants from five age groups (9–14, 18–25, 35–55, 65–80, 80+) participated in the study (N = 96). While we found no age difference for DoG, DD was the lowest [i.e., self-control (SC) was the highest] in young/middle adults; however, it was the highest (i.e., SC was the lowest) in children and old/oldest adults. Furthermore, we found significant age differences for DD and FTP. As predicted, there were strong correlations between DoG and FTP and between DD and FTP, but not between DoG/DD and EFT. These results indicate that age differences in SR vary across the measures used. Individuals who generally think and act in a future-oriented manner have a stronger ability to delay gratification. PMID:29422875

32 CFR 536.132 - Procedure for processing UCMJ claims.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the claim determines there is good cause for delay. Lack of knowledge of the existence of Article 139, or lack of knowledge of the identity of the offender, are examples of good cause for delay. (b) Form... procedures. When assessment action on a particular claim will be unduly delayed, the claims office supporting...

An adaptive, individualized fMRI delay discounting procedure to increase flexibility and optimize scanner time.

PubMed

Koffarnus, Mikhail N; Deshpande, Harshawardhan U; Lisinski, Jonathan M; Eklund, Anders; Bickel, Warren K; LaConte, Stephen M

2017-11-01

Research on the rate at which people discount the value of future rewards has become increasingly prevalent as discount rate has been shown to be associated with many unhealthy patterns of behavior such as drug abuse, gambling, and overeating. fMRI research points to a fronto-parietal-limbic pathway that is active during decisions between smaller amounts of money now and larger amounts available after a delay. Researchers in this area have used different variants of delay discounting tasks and reported various contrasts between choice trials of different types from these tasks. For instance, researchers have compared 1) choices of delayed monetary amounts to choices of the immediate monetary amounts, 2) 'hard' choices made near one's point of indifference to 'easy' choices that require little thought, and 3) trials where an immediate choice is available versus trials where one is unavailable, regardless of actual eventual choice. These differences in procedure and analysis make comparison of results across studies difficult. In the present experiment, we designed a delay discounting task with the intended capability of being able to construct contrasts of all three comparisons listed above while optimizing scanning time to reduce costs and avoid participant fatigue. This was accomplished with an algorithm that customized the choice trials presented to each participant with the goal of equalizing choice trials of each type. We compared this task, which we refer to here as the individualized discounting task (IDT), to two other delay discounting tasks previously reported in the literature (McClure et al., 2004; Amlung et al., 2014) in 18 participants. Results show that the IDT can examine each of the three contrasts mentioned above, while yielding a similar degree of activation as the reference tasks. This suggests that this new task could be used in delay discounting fMRI studies to allow researchers to more easily compare their results to a majority of previous research while minimizing scanning duration. Copyright © 2017 Elsevier Inc. All rights reserved.

Cross delay line sensor characterization

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

Owens, Israel J; Remelius, Dennis K; Tiee, Joe J

There exists a wealth of information in the scientific literature on the physical properties and device characterization procedures for complementary metal oxide semiconductor (CMOS), charge coupled device (CCD) and avalanche photodiode (APD) format detectors. Numerous papers and books have also treated photocathode operation in the context of photomultiplier tube (PMT) operation for either non imaging applications or limited night vision capability. However, much less information has been reported in the literature about the characterization procedures and properties of photocathode detectors with novel cross delay line (XDL) anode structures. These allow one to detect single photons and create images by recordingmore » space and time coordinate (X, Y & T) information. In this paper, we report on the physical characteristics and performance of a cross delay line anode sensor with an enhanced near infrared wavelength response photocathode and high dynamic range micro channel plate (MCP) gain (> 10{sup 6}) multiplier stage. Measurement procedures and results including the device dark event rate (DER), pulse height distribution, quantum and electronic device efficiency (QE & DQE) and spatial resolution per effective pixel region in a 25 mm sensor array are presented. The overall knowledge and information obtained from XDL sensor characterization allow us to optimize device performance and assess capability. These device performance properties and capabilities make XDL detectors ideal for remote sensing field applications that require single photon detection, imaging, sub nano-second timing response, high spatial resolution (10's of microns) and large effective image format.« less

Robust reliable sampled-data control for switched systems with application to flight control

NASA Astrophysics Data System (ADS)

Sakthivel, R.; Joby, Maya; Shi, P.; Mathiyalagan, K.

2016-11-01

This paper addresses the robust reliable stabilisation problem for a class of uncertain switched systems with random delays and norm bounded uncertainties. The main aim of this paper is to obtain the reliable robust sampled-data control design which involves random time delay with an appropriate gain control matrix for achieving the robust exponential stabilisation for uncertain switched system against actuator failures. In particular, the involved delays are assumed to be randomly time-varying which obeys certain mutually uncorrelated Bernoulli distributed white noise sequences. By constructing an appropriate Lyapunov-Krasovskii functional (LKF) and employing an average-dwell time approach, a new set of criteria is derived for ensuring the robust exponential stability of the closed-loop switched system. More precisely, the Schur complement and Jensen's integral inequality are used in derivation of stabilisation criteria. By considering the relationship among the random time-varying delay and its lower and upper bounds, a new set of sufficient condition is established for the existence of reliable robust sampled-data control in terms of solution to linear matrix inequalities (LMIs). Finally, an illustrative example based on the F-18 aircraft model is provided to show the effectiveness of the proposed design procedures.

Tuning algorithms for fractional order internal model controllers for time delay processes

NASA Astrophysics Data System (ADS)

Muresan, Cristina I.; Dutta, Abhishek; Dulf, Eva H.; Pinar, Zehra; Maxim, Anca; Ionescu, Clara M.

2016-03-01

This paper presents two tuning algorithms for fractional-order internal model control (IMC) controllers for time delay processes. The two tuning algorithms are based on two specific closed-loop control configurations: the IMC control structure and the Smith predictor structure. In the latter, the equivalency between IMC and Smith predictor control structures is used to tune a fractional-order IMC controller as the primary controller of the Smith predictor structure. Fractional-order IMC controllers are designed in both cases in order to enhance the closed-loop performance and robustness of classical integer order IMC controllers. The tuning procedures are exemplified for both single-input-single-output as well as multivariable processes, described by first-order and second-order transfer functions with time delays. Different numerical examples are provided, including a general multivariable time delay process. Integer order IMC controllers are designed in each case, as well as fractional-order IMC controllers. The simulation results show that the proposed fractional-order IMC controller ensures an increased robustness to modelling uncertainties. Experimental results are also provided, for the design of a multivariable fractional-order IMC controller in a Smith predictor structure for a quadruple-tank system.

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay

PubMed Central

Strickland, Justin C.; Feinstein, Max A.; Lacy, Ryan T.; Smith, Mark A.

2016-01-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-second delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. PMID:26964905

Primary Realignment for Pelvic Fracture Urethral Injury Is Associated With Prolonged Time to Urethroplasty and Increased Stenosis Complexity.

PubMed

Horiguchi, Akio; Shinchi, Masayuki; Masunaga, Ayako; Okubo, Kazuki; Kawamura, Kazuki; Ojima, Kenichiro; Ito, Keiichi; Asano, Tomohiko; Azuma, Ryuichi

2017-10-01

To compare the clinical courses of patients with pelvic fracture urethral injury (PFUI) according to initial management strategy. We reviewed the clinical courses of 63 patients with PFUI who were initially treated elsewhere and underwent delayed anastomotic urethroplasty by a single surgeon between 2008 and 2015. Patients were grouped according to their initial treatment: by suprapubic tube placement alone (49 patients, SPT group) or primary realignment (14 patients, PR group). Time to urethroplasty was defined as the period between injury and delayed urethroplasty. Clinical data regarding the status of urethral stenosis, urethroplasty procedure, and treatment outcome were analyzed. The mean time to urethroplasty in the PR group was about 3 times than that in the SPT group (133 months vs 47 months, P = .035). Fifty percent of the PR group (7 of 14) had a history of repeated urethrotomy or dilation before referral, a percentage significantly higher than that of the SPT group (20.4%, 10 of 49, P = .027). The percentage of patients having a false passage and iatrogenic scar was significantly higher in the PR group (42.9% vs 16.3%, P = .035), but there was no significant between-group difference in urethral stenosis length, operative time, operative blood loss, or the percentage of patients requiring inferior pubectomy or urethral rerouting. PR does not facilitate delayed urethroplasty, and patients who undergo PR are at high risk of having a more complicated stenosis and longer time to urethroplasty, presumably because of repeated transurethral procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

Movement suppression time-out for undesirable behavior in psychotic and severely developmentally delayed children.

PubMed

Rolider, A; Van Houten, R

1985-01-01

The effects of a movement suppression time-out, which involved punishing any movement or verbalization while a client is in the time-out area, were evaluated in four experiments. The first experiment examined the effects of a DRO procedure and movement suppression plus DRO in suppressing self-injurious behavior in a psychotic child in three different situations. In Experiment 2, the results of the previous experiment were replicated with two dangerous behaviors in a second psychotic child. In a third experiment, movement suppression plus DRO was compared with contingent restraint in reducing inappropriate poking behavior in two settings. The movement suppression procedure eliminated poking whereas contingent restraint had little effect. In the final experiment, movement suppression time-out alone was compared with exclusionary time-out alone and simple corner time-out alone. Self-stimulation occurred at high levels during the exclusionary and simple corner time-out procedures. Self-stimulation was either suppressed or reduced during movement suppression time-out. The movement suppression time-out procedure produced a larger reduction in the target behavior in all three children. The effectiveness of the movement suppression procedure was explained in terms of the suppression of self-stimulation while the time-out procedure was being applied.

Rapid bedside coagulometry prior to urgent neurosurgical procedures in anticoagulated patients.

PubMed

Beynon, Christopher; Jakobs, Martin; Rizos, Timolaos; Unterberg, Andreas W; Sakowitz, Oliver W

2014-01-01

With the increased use of oral anticoagulation with vitamin K antagonists, emergency physicians encounter a growing number of patients requiring a rapid reversal of anticoagulant effects in order to perform urgent surgical procedures. Initiation of these procedures can be delayed because the coagulation status has to be assessed through examination of blood samples in central laboratories (CL). This delay may lead to negative effects, especially in potentially life-threatening conditions such as intracranial haemorrhage. Point-of-care (POC) devices for assessment of international normalized ratio (POC INR) have improved the management of anticoagulation therapy in the outpatient setting. The use of these devices may also have beneficial effects in the treatment of anticoagulated patients requiring urgent neurosurgical procedures. The primary aim of this study was to analyse the potential of POC-guided assessment of INR to reduce time to potentially life-saving neurosurgery in this setting. Feasibility and accuracy as well as the gain of time through the use of this device were analysed. The POC coagulometer CoaguChek XS(®) was used in 17 patients with a history of anticoagulant use and a condition requiring urgent anticoagulant reversal prior to neurosurgical procedures (burr-hole trepanation: n = 8, craniotomy: n = 7, laminectomy: n = 2). No technical difficulties occurred and rapid assessment of INR was achieved in all cases within 2 min. POC INR values correlated well with CL INR assessment with a mean INR deviation of 0.036 ± 0.12. The mean gain of time through the use of the POC INR device compared with CL assessment of INR was 47 ± 6 min (range: 37-61 min). Our initial experiences with a POC INR device in anticoagulated patients undergoing urgent neurosurgical procedures demonstrate that its use may contribute to an improved management of these patients.

Endovascular strategy for the elective treatment of concomitant aortoiliac aneurysm and symptomatic large bowel diverticular disease.

PubMed

Illuminati, Giulio; Ricco, Jean-Baptiste; Schneider, Fabrice; Caliò, Francesco G; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

2014-07-01

The purpose of this study was to evaluate the strategy for treatment of patients presenting with asymptomatic diverticular disease of the large bowel associated with an asymptomatic aortoiliac aneurysmal (AAA) disease. Sixty-nine patients were included in this retrospective study. The patients were divided into 5 groups according to the type and sequence of the surgical treatment: 32 patients (47%) underwent colectomy followed by a staged open AAA repair (group A); 10 patients (14%) were treated with open AAA repair followed by a staged colectomy (group B); 13 patients (18%) received endovascular aneurysm repair (EVAR) followed by a staged bowel resection (group C); 8 patients (12%) had a bowel resection followed by staged EVAR (group D); and 6 patients (9%) underwent simultaneous open AAA repair and bowel resection (group E). Primary end points were mortality and complications after any of the procedures. Secondary end point was the time interval between the staged procedures. The cumulative death rate for delayed treatment of AAA was 6.5% and 0% for delayed treatment of diverticular disease [P=0.22]. The mean time interval between the staged procedures was 11 days for EVAR/colon resection (group C and group D) and 73 days for open AAA repair/colon resection (group A and group B; P<0.01). EVAR allows a significant reduction in the time required between AAA repair and colon resection, but no definite rule can be established regarding the sequence of staged procedures. Combined procedures should be reserved for selected cases. Copyright © 2014 Elsevier Inc. All rights reserved.

Meta-analysis of Timing for Microsurgical Free-Flap Reconstruction for Lower Limb Injury: Evaluation of the Godina Principles.

PubMed

Haykal, Siba; Roy, Mélissa; Patel, Ashit

2018-05-01

 In 1986, Marko Godina published his seminal work regarding the timing of free-flap reconstruction for traumatic extremity defects. Early reconstruction, compared with delayed and late reconstruction resulted in significant decreases in free-flap failure rate, post-operative infections, hospitalization time, bone healing time, and number of additional anesthesias. The objective of this manuscript was to evaluate whether these principles continue to apply.  A meta-analysis was performed analyzing articles from Medline, Embase, and Pubmed. Four hundred and ninety-two articles were screened, and 134 articles were assessed for eligibility. Following full-text review, 43 articles were included in this study.  The exact timing for free-flap reconstruction, free-flap failure rate, infection rate, and follow-up was defined in all 43 articles. Early free-flap reconstruction was found to have significantly lower rates of free-flap failure and infection in comparison to delayed reconstruction ( p  = 0.008; p  = 0.0004). Compared with late reconstruction, early reconstruction was found to have significantly lower infection rates only ( p  = 0.01) with no difference in free-flap failures rates. Early reconstruction was found to lead to fewer additional procedures ( p  = 0.03). No statistical significance was found for bone healing time or hospitalization time.  Early free-flap reconstruction performed within the first 72 hours resulted in a decreased rate of free-flap failures, infection, and additional procedures with no difference in other parameters. The largest majority of free flaps continue to be performed in a delayed time frame. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Vascular delay improves latissimus dorsi muscle perfusion and muscle function for use in cardiomyoplasty.

PubMed

Carroll, S M; Heilman, S J; Stremel, R W; Tobin, G R; Barker, J H

1997-04-01

Ischemia of the distal portion of the latissimus dorsi muscle occurs in muscle transfer for cardiomyoplasty and reduces distal muscle contractility and thus the mechanical effectiveness of cardiomyoplasty. We hypothesized that muscle function would be improved by a vascular delay procedure that increases distal muscle perfusion of the latissimus dorsi muscle. The latissimus dorsi muscles of 10 adult mongrel dogs were subjected to a vascular delay procedure on one side and a sham procedure on the other. Following 10 days of vascular delay, muscle perfusion was measured with a laser-Doppler perfusion imager before and after elevation of the muscles as flaps based only on their thoracodorsal neurovascular pedicles. The muscles were wrapped and sutured around silicone chambers (simulating cardiomyoplasty), a stimulating electrode was placed around each thoracodorsal nerve, and the muscles were stimulated to contract in both rhythmic and tetanic fashion. Circumferential (distal and middle latissimus dorsi muscle function) force generation and fatigue rates were measured independently. Circumferential muscle force, circumferential and longitudinal fatigue rate, and distal, middle, and overall perfusion were significantly (p < 0.05) improved in delayed muscle compared with nondelayed muscle. We found that a vascular delay procedure and a 10-day delay adaptation period significantly improve latissimus dorsi muscle flap perfusion and function, particularly in the distal and middle portions of the muscle. Delay should be considered as a means of improving the clinical outcome in cardiomyoplasty.

Is Maintenance Electroconvulsive Therapy Always an Elective Procedure?: Weighing Medical Versus Psychiatric Risk.

PubMed

Rosenthal, Isobel A; Kellner, Charles H

2018-03-01

Because of the severe nature of psychiatric illness, electroconvulsive therapy (ECT) is not always an "elective procedure." The pre-ECT medical evaluation, although important, should not be an impediment to timely ECT. We argue that an arbitrary regulation requiring new assessments every 30 days may be unduly burdensome and unnecessary. The small medical risk of treatment should be weighed against the potential psychiatric risk (including suicide) of delayed treatment.

An overview of radioactive waste disposal procedures of a nuclear medicine department

PubMed Central

Ravichandran, R.; Binukumar, J. P.; Sreeram, Rajan; Arunkumar, L. S.

2011-01-01

Radioactive wastes from hospitals form one of the various types of urban wastes, which are managed in developed countries in a safe and organized way. In countries where growth of nuclear medicine services are envisaged, implementations of existing regulatory policies and guidelines in hospitals in terms of handling of radioactive materials used in the treatment of patients need a good model. To address this issue, a brief description of the methods is presented. A designed prototype waste storage trolley is found to be of great help in decaying the I-131 solid wastes from wards before releasing to waste treatment plant of the city. Two delay tanks with collection time of about 2 months and delay time of 2 months alternately result in 6 releases of urine toilet effluents to the sewage treatment plant (STP) of the hospital annually. Samples of effluents collected at releasing time documented radioactive releases of I-131 much below recommended levels of bi-monthly release. External counting of samples showed good statistical correlation with calculated values. An overview of safe procedures for radioactive waste disposal is presented. PMID:21731225

An overview of radioactive waste disposal procedures of a nuclear medicine department.

PubMed

Ravichandran, R; Binukumar, J P; Sreeram, Rajan; Arunkumar, L S

2011-04-01

Radioactive wastes from hospitals form one of the various types of urban wastes, which are managed in developed countries in a safe and organized way. In countries where growth of nuclear medicine services are envisaged, implementations of existing regulatory policies and guidelines in hospitals in terms of handling of radioactive materials used in the treatment of patients need a good model. To address this issue, a brief description of the methods is presented. A designed prototype waste storage trolley is found to be of great help in decaying the I-131 solid wastes from wards before releasing to waste treatment plant of the city. Two delay tanks with collection time of about 2 months and delay time of 2 months alternately result in 6 releases of urine toilet effluents to the sewage treatment plant (STP) of the hospital annually. Samples of effluents collected at releasing time documented radioactive releases of I-131 much below recommended levels of bi-monthly release. External counting of samples showed good statistical correlation with calculated values. An overview of safe procedures for radioactive waste disposal is presented.

Parathyroid cryopreservation following parathyroidectomy: a worthwhile practice?

PubMed Central

Shepet, Kevin; Alhefdhi, Amal; Usedom, Reid; Sippel, Rebecca; Chen, Herbert

2013-01-01

Background Parathyroid cryopreservation is often utilized for patients having parathyroidectomy. This allows for future autotransplantation if a patient becomes permanently hypocalcemic after surgery. However, the practice of cryopreservation is costly and time consuming, while the success rate of delayed autotransplantation is highly variable. We sought to determine the rate and outcomes of parathyroid cryopreservation and delayed autotransplantation at our institution to further evaluate its utility. Methods At our institution, 2,083 parathyroidectomies for hyperparathyroidism (HPT) were performed from 2001–2010. Of these, parathyroid cryopreservation was utilized in 442 patients (21%). Patient demographics, preoperative diagnoses, and other characteristics were analyzed, as well as the rate and success of delayed autotransplantation. Results Of the 442 patients with cryopreservation, the mean age was 55 ± 1 years and 313 (70.8%) were female. 308 (70%) had primary HPT, 46 (10%) had secondary HPT, and 88 (20%) had tertiary HPT. Delayed autotransplantation of cryopreserved parathyroid tissue was used in 4 (1%) patients at an average time of 9 ± 4 months after initial surgery. 3 out of the 4 patients remained hypoparathyroid following this procedure. The one cured patient underwent the procedure only 4 days following the initial parathyroidectomy. Conclusion While cryopreservation was used in over 1/5 of patients undergoing parathyroidectomy, the need for parathyroid reimplantation was very low (1%). Furthermore, the success rate of parathyroid autotransplantation was poor in these patients. Therefore, the continued practice of parathyroid cryopreservation is questionable. PMID:23504122

Delay Discounting: Pigeon, Rat, Human – Does it Matter?

PubMed Central

Vanderveldt, Ariana; Oliveira, Luís; Green, Leonard

2016-01-01

Delay discounting refers to the decrease in subjective value of an outcome as the time to its receipt increases. Across species and situations, animals discount delayed rewards, and their discounting is well-described by a hyperboloid function. The current review begins with a comparison of discounting models and the procedures used to assess delay discounting in nonhuman animals. We next discuss the generality of discounting, reviewing the effects of different variables on the degree of discounting delayed reinforcers by nonhuman animals. Despite the many similarities in discounting observed between human and nonhuman animals, several differences have been proposed (e.g., the magnitude effect; nonhuman animals discount over a matter of seconds whereas humans report willing to wait months, if not years before receiving a reward), raising the possibility of fundamental species differences in intertemporal choice. After evaluating these differences, we discuss delay discounting from an adaptationist perspective. The pervasiveness of discounting across species and situations suggests it is a fundamental process underlying decision making. PMID:26881899

Cancellation of scheduled procedures as a mechanism to generate hospital bed surge capacity-a pilot study.

PubMed

Soremekun, Olan A; Zane, Richard D; Walls, Andrew; Allen, Matthew B; Seefeld, Kimberly J; Pallin, Daniel J

2011-06-01

The ability to generate hospital beds in response to a mass-casualty incident is an essential component of public health preparedness. Although many acute care hospitals' emergency response plans include some provision for delaying or cancelling elective procedures in the event of an inpatient surge, no standardized method for implementing and quantifying the impact of this strategy exists in the literature. The aim of this study was to develop a methodology to prospectively emergency plan for implementing a strategy of delaying procedures and quantifying the potential impact of this strategy on creating hospital bed capacity. This is a pilot study. A categorization methodology was devised and applied retrospectively to all scheduled procedures during four one-week periods chosen by convenience. The categorization scheme grouped procedures into four categories: (A) procedures with no impact on inpatient capacity; (B) procedures that could be delayed indefinitely; (C) procedures that could be delayed by one week; and (D) procedures that could not be delayed. The categorization scheme was applied by two research assistants and an emergency medicine resident. All three raters categorized the first 100 cases to allow for calculation of inter-rater reliability. Maximal hospital bed capacity was defined as the 95th percentile weekday occupancy, as this is more representative of functional bed capacity than is the number of licensed beds. The main outcome was the number of hospital beds that could be created by postponing procedures in categories B and C. Maximal hospital bed capacity was 816 beds. Mean occupancy during weekdays was 759 versus 694 on weekends. By postponing Group B and C procedures, a mean of 60 beds (51 general medical/surgical and nine intensive care unit (ICU)) could be created on weekdays, and four beds (three general medical/surgical and one ICU) on weekends. This represents 7.3% and 0.49% of maximal hospital bed capacity and ICU capacity, respectively. In the event that sustained surge is needed, delaying all category B and C procedures for one week would lead to the generation of 1,235 hospital-bed days. Inter-rater reliability was high (kappa = 0.74) indicating good agreement between all three raters. For the institution studied, the strategy of delaying scheduled procedures could generate inpatient capacity with maximal impact during weekdays and little impact on weekends. Future research is needed to validate the categorization scheme and increase the ability to predict inpatient surge capacity across various hospital types and sizes.

Immediate vs delayed repair bond strength of a nanohybrid resin composite.

PubMed

El-Askary, Farid S; El-Banna, Ahmed H; van Noort, Richard

2012-06-01

To evaluate both the immediate and water-stored repair tensile bond strength (TBS) of a nanohybrid resin composite using different bonding protocols. One hundred sixty half hourglass-shaped slabs were prepared. Eighty half-slabs were wet ground immediately after light curing using high-speed abrasive burs, while the other half-slabs were stored in water for one month (delayed) and then wet ground for repair. Each set of the 80 repaired slabs was split into two groups to be tested for TBS after 24 h or 1 month of water storage. For all repaired slabs, either immediate or delayed, four bonding procedures were used involving wet and dry bonding with a 3-step etch-and-rinse adhesive with or without silane pretreatment. TBS tests were performed at a crosshead speed of 0.5 mm/min. To determine the cohesive strength of the resin composite itself, which served as the reference, additional whole slabs were prepared and tested in tension after a 24-h (n = 10) and a 1-month storage period (n = 10). Failure modes were evaluated using a stereomicroscope at 40X magnification. Three-way ANOVA was run to test the effect of water storage, testing time, bonding protocols, and their interactions on the repair TBS, which was given as a percentage of the reference values. For the immediate repair groups, the repair TBS ranged from 40% to 61.9% after 24-h storage and from 26% to 53.1% after 1-month water storage compared to the TBS of the whole slabs. For the delayed repair group, the repaired TBS ranged from 47.2% to 63.6% for the 24-h repairs and from 32.2% to 44.2% for the test groups stored in water for 1 month. Three-way ANOVA revealed that water storage had no significant effect on the repair TBS (p = 0.619). Both testing time and bonding protocols had a significant effect on the repair TBS (p = 0.001). The interactions between the independent variables (water storage, testing time, and bonding protocols) had no significant effect (p = 0.067). The repair bond strength was consistently and highly significantly less than the cohesive strength of the composite. A delay of 1 month before carrying out the repair had no effect on the bond strength, irrespective of the bonding procedure used. Silane treatment did not improve the repair bond strength. In all instances, except for the immediate wet bonding plus silane procedure and delayed dry bonding, the bond strength of the repairs significantly dropped after 1 month of storage in water.

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay.

PubMed

Strickland, Justin C; Feinstein, Max A; Lacy, Ryan T; Smith, Mark A

2016-05-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-s delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of shipborne GNSS-derived precipitable water vapor with radiosonde in the western North Pacific and in the seas adjacent to Japan

NASA Astrophysics Data System (ADS)

Shoji, Yoshinori; Sato, Kazutoshi; Yabuki, Masanori; Tsuda, Toshitaka

2017-11-01

We installed two global navigation satellite system (GNSS) antennas on a research vessel, the RYOFU MARU of the Japan Meteorological Agency, and conducted experimental observations to assess the GNSS-derived precipitable water vapor (PWV) from October 19, 2016, to August 6, 2017. One antenna was set on the mast (MAST), while another antenna was set on the upper deck (DECK). The GNSS analysis was conducted using the precise point positioning procedure with a real-time GNSS orbit. A quality control (QC) procedure based on the amount of zenith tropospheric delay (ZTD) time variation was proposed. After the QC was applied, the retrieved PWVs were compared to 77 radiosonde observations. The PWVs of MAST agreed with the radiosonde observations with a 1.7 mm root mean square (RMS) difference, a - 0.7-mm bias, and 3.6% rejection rate, while that of DECK showed a 3.2, - 0.8 mm, and 15.7%. The larger RMS and higher rejection rate of DECK imply a stronger multi-path effect on the deck. The differences in the GNSS PWV versus radiosonde observations were compared to the atmospheric delay, the estimated altitude of the GNSS antenna, the vessel's moving speed, the wind speed, and the wave height. The atmospheric delay and GNSS antenna altitude showed moderate correlation with the differences. The results suggest the kinematic PPP's potential for practical water vapor monitoring over oceans worldwide. At the same time, from the growing negative biases with the PWV value and with estimated antenna altitude, it could be inferred that the difficulty grows in separating the signal delay from the vertical coordinate under high-humidity conditions.[Figure not available: see fulltext.

Accelerated forgetting? An evaluation on the use of long-term forgetting rates in patients with memory problems

PubMed Central

Geurts, Sofie; van der Werf, Sieberen P.; Kessels, Roy P. C.

2015-01-01

The main focus of this review was to evaluate whether long-term forgetting rates (delayed tests, days, to weeks, after initial learning) are more sensitive measures than standard delayed recall measures to detect memory problems in various patient groups. It has been suggested that accelerated forgetting might be characteristic for epilepsy patients, but little research has been performed in other populations. Here, we identified eleven studies in a wide range of brain injured patient groups, whose long-term forgetting patterns were compared to those of healthy controls. Signs of accelerated forgetting were found in three studies. The results of eight studies showed normal forgetting over time for the patient groups. However, most of the studies used only a recognition procedure, after optimizing initial learning. Based on these results, we recommend the use of a combined recall and recognition procedure to examine accelerated forgetting and we discuss the relevance of standard and optimized learning procedures in clinical practice. PMID:26106343

Controlled environment life support system: Calcium-related leaf injuries on plants

NASA Technical Reports Server (NTRS)

Tibbitts, T. W.

1986-01-01

Calcium related injuries to plants grown in controlled environments under conditions which maximize plant growth rates are described. Procedures to encourage movement of calcium into developing leaves of lettuce plants were investigated. The time course and pattern of calcium accumulation was determined to develop effective control procedures for this injury, termed tipburn. Procedures investigated were: (1) increasing the relative humidity to saturation during the dark period and altering root temperatures, (2) maximizing water stress during light and minimizing water stress during dark periods, (3) shortening the light-dark cycle lengths in combination with elevated moisture levels during the dark cycles, (4) reducing nutrient concentrations and (5) vibrating the plants. Saturated humidities at night increased the rate of growth and the large fluctuation in plant water potential encouraged calcium movement to the young leaves and delayed tipburn. Root temperature regulation between 15 and 26 C was not effective in preventing tipburn. Attempts to modulate water stress produced little variation, but no difference in tipburn development. Variations in light-dark cycle lengths also had no effect on calcium concentrations within developing leaves and no variation in tipburn development. Low concentrations of nutrient solution delayed tipburn, presumably because of greater calcium transport in the low concentration plants. Shaking of the plants did not prevent tipburn, but did delay it slightly.

Modelling the impact of causal and non-causal factors on disruption duration for Toronto's subway system: An exploratory investigation using hazard modelling.

PubMed

Louie, Jacob; Shalaby, Amer; Habib, Khandker Nurul

2017-01-01

Most investigations of incident-related delay duration in the transportation context are restricted to highway traffic, with little attention given to delays due to transit service disruptions. Studies of transit-based delay duration are also considerably less comprehensive than their highway counterparts with respect to examining the effects of non-causal variables on the delay duration. However, delays due to incidents in public transit service can have serious consequences on the overall urban transportation system due to the pivotal and vital role of public transit. The ability to predict the durations of various types of transit system incidents is indispensable for better management and mitigation of service disruptions. This paper presents a detailed investigation on incident delay durations in Toronto's subway system over the year 2013, focusing on the effects of the incidents' location and time, the train-type involved, and the non-adherence to proper recovery procedures. Accelerated Failure Time (AFT) hazard models are estimated to investigate the relationship between these factors and the resulting delay duration. The empirical investigation reveals that incident types that impact both safety and operations simultaneously generally have longer expected delays than incident types that impact either safety or operations alone. Incidents at interchange stations are cleared faster than incidents at non-interchange stations. Incidents during peak periods have nearly the same delay durations as off-peak incidents. The estimated models are believed to be useful tools in predicting the relative magnitude of incident delay duration for better management of subway operations. Copyright © 2016 Elsevier Ltd. All rights reserved.

The critical dimensions of the response-reinforcer contingency.

PubMed

Williams, B A.

2001-05-03

Two major dimensions of any contingency of reinforcement are the temporal relation between a response and its reinforcer, and the relative frequency of the reinforcer given the response versus when the response has not occurred. Previous data demonstrate that time, per se, is not sufficient to explain the effects of delay-of-reinforcement procedures; needed in addition is some account of the events occurring in the delay interval. Moreover, the effects of the same absolute time values vary greatly across situations, such that any notion of a standard delay-of-reinforcement gradient is simplistic. The effects of reinforcers occurring in the absence of a response depend critically upon the stimulus conditions paired with those reinforcers, in much the same manner as has been shown with Pavlovian contingency effects. However, it is unclear whether the underlying basis of such effects is response competition or changes in the calculus of causation.

SSRIs and ejaculation: a double-blind, randomized, fixed-dose study with paroxetine and citalopram.

PubMed

Waldinger, M D; Zwinderman, A H; Olivier, B

2001-12-01

Selective serotonin reuptake inhibitors (SSRIs) are known to induce delayed orgasm and ejaculation. However, different SSRIs may differentially delay ejaculation. A double-blind, fixed-dose study in healthy men with lifelong rapid ejaculation was performed to evaluate potential differences between clinically relevant doses of two selective serotonin reuptake inhibitors, paroxetine and citalopram, in their effects on ejaculation. Thirty men with an intravaginal ejaculation latency time (IELT) less than 1 minute were randomly assigned to receive paroxetine (20 mg/day) and citalopram (20 mg/day) for 5 weeks, after taking half the dosage in the first week. During the 1-month baseline and 6-week treatment period, IELTs were measured at home by using a stopwatch procedure. The trial was completed by 23 men. Analysis of variance revealed a between-group difference in the evolution of IELT delay over time (p = 0.0004); the IELT after paroxetine and citalopram gradually increased from 18 and 21 seconds to approximately 170 and 44 seconds, respectively. Paroxetine 20 mg/day exerted a strong delay (8.9-fold increase), whereas citalopram 20 mg/day mildly delayed ejaculation (1.8-fold increase). These results indicate that paroxetine leads to a significant delay in orgasm and ejaculation, whereas citalopram seems to have less of an effect on it.

Pancreaticoduodenectomy for pancreatic head cancer: PPPD versus Whipple procedure.

PubMed

Lin, Pin-Wen; Shan, Yan-Shen; Lin, Yih-Jyh; Hung, Chung-Jye

2005-01-01

Resectable carcinoma of the head of the pancreas can be treated with either standard (the Whipple) or pylorus-preserving pancreaticoduodenectomy (PPPD). Only a few reports compared the differences between these two procedures. From July 1994 to Oct 2002, a prospective randomized comparison between the Whipple procedure and PPPD done by the same surgeon for the patients with carcinoma of the head of the pancreas was conducted. Thirty-six patients diagnosed as pancreatic head adenocarcinoma were randomized to receive either the Whipple procedure or a PPPD. Three patients initially randomized to have a PPPD were converted to the Whipple procedure due to gross duodenal involvement. Finally, 19 patients received the Whipple procedure, 14 patients underwent PPPD and three patients had conversion. Two perioperative deaths in the Whipple group and one perioperative death in PPPD resulted in an 8 percent mortality rate in the 36 patients. Median duration of the Whipple operation was 265 (range 203-475) min with a median blood loss of 570 (50-8540) mL. In the patients who had PPPD, median operating time was 232 (range 165-270) min, and median blood loss was 375 (range 100-1300) mL. There was one minor leak from the pancreaticojejunostomy in each group, resulting in a 5.5 percent minor leak in 36 patients. These outcomes were not significantly different. Delayed gastric emptying was observed more frequently after PPPD (six of 14 patients) than after the Whipple procedure (none of 19 patients) (P < 0.05). There was no significant difference between the Whipple procedure and PPPD in terms of median survival and 5-year survival rate. The median survival time was 16.0 months and 5-year survival rate was 9.4 percent in the 36 patients. Blood loss during operation influenced the prognosis. There was no significant difference between the Whipple procedure and PPPD for the treatment of pancreatic head cancer in terms of operating time, blood loss, operative mortality and long-term survival. But delayed gastric emptying was more frequently encountered in PPPD than in the Whipple procedure.

Computer-Based Reading Instruction for Young Children with Disabilities

ERIC Educational Resources Information Center

Lee, Yeunjoo; Vail, Cynthia O.

2005-01-01

This investigation examined the effectiveness of a computer program in teaching sight word recognition to four young children with developmental disabilities. The intervention program was developed through a formative evaluation process. It embedded a constant-time-delay procedure and involved sounds, video, text, and animations. Dependent…

A Temporal Discriminability Account of Children's Eyewitness Suggestibility

ERIC Educational Resources Information Center

Bright-Paul, Alexandra; Jarrold, Christopher

2009-01-01

Children's suggestibility is typically measured using a three-stage "event-misinformation-test" procedure. We examined whether suggestibility is influenced by the time delays imposed between these stages, and in particular whether the temporal discriminability of sources (event and misinformation) predicts performance. In a novel approach, the…

Construction procedures using self hardening fly ash

NASA Astrophysics Data System (ADS)

Thornton, S. I.; Parker, D. G.

1980-07-01

Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

Facilitating relational framing in children and individuals with developmental delay using the relational completion procedure.

PubMed

Walsh, Sinead; Horgan, Jennifer; May, Richard J; Dymond, Simon; Whelan, Robert

2014-01-01

The Relational Completion Procedure is effective for establishing same, opposite and comparative derived relations in verbally able adults, but to date it has not been used to establish relational frames in young children or those with developmental delay. In Experiment 1, the Relational Completion Procedure was used with the goal of establishing two 3-member sameness networks in nine individuals with Autism Spectrum Disorder (eight with language delay). A multiple exemplar intervention was employed to facilitate derived relational responding when required. Seven of nine participants in Experiment 1 passed tests for derived relations. In Experiment 2, eight participants (all of whom, except one, had a verbal repertoire) were given training with the aim of establishing two 4-member sameness networks. Three of these participants were typically developing young children aged between 5 and 6 years old, all of whom demonstrated derived relations, as did four of the five participants with developmental delay. These data demonstrate that it is possible to reliably establish derived relations in young children and those with developmental delay using an automated procedure. © Society for the Experimental Analysis of Behavior.

Guidance concepts for time-based flight operations

NASA Technical Reports Server (NTRS)

Vicroy, Dan D.

1990-01-01

Airport congestion and the associated delays are severe in today's airspace system and are expected to increase. NASA and the FAA is investigating various methods of alleviating this problem through new technology and operational procedures. One concept for improving airspace productivity is time-based control of aircraft. Research to date has focused primarily on the development of time-based flight management systems and Air Traffic Control operational procedures. Flight operations may, however, require special onboard guidance in order to satisfy the Air Traffic Control imposed time constraints. The results are presented of a simulation study aimed at evaluating several time-based guidance concepts in terms of tracking performance, pilot workload, and subjective preference. The guidance concepts tested varied in complexity from simple digital time-error feedback to an advanced time-referenced-energy guidance scheme.

Real-time minimal-bit-error probability decoding of convolutional codes

NASA Technical Reports Server (NTRS)

Lee, L.-N.

1974-01-01

A recursive procedure is derived for decoding of rate R = 1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit, subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e., fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications, such as in the inner coding system for concatenated coding.

Real-time minimal bit error probability decoding of convolutional codes

NASA Technical Reports Server (NTRS)

Lee, L. N.

1973-01-01

A recursive procedure is derived for decoding of rate R=1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e. fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications such as in the inner coding system for concatenated coding.

"Turn laterally to the left!". The need for uniform C-arm communication terminology during orthopaedic trauma surgery.

PubMed

De Muinck Keizer, R-J; Klei, D S; Van Koperen, P J; Van Dijk, C N; Goslings, J C

2017-03-01

To avoid disturbed teamwork, unnecessary radiation exposure, and procedural delays, we designed and tested a uniform communication language for use in fluoroscopy-assisted surgical procedures. Input of surgeons and radiographers was used to create a set of commands. The potential benefit of this terminology was explored in an experimental setting. There was a tremendous diversity in the currently used terminology. Use of the newly designed terminology showed a reduction of procedural time and amount of images needed. Our first standardized Dutch language terminology can reduce total fluoroscopy time, number of images acquired, and potentially radiation exposure. For Dutch speaking colleagues, the developed terminology is freely available for use in their OR.

Failure to comply with CMS' new enrollment procedures could impact physicians' cash flow.

PubMed

Duffy, Erin M

2007-01-01

The Centers for Medicare and Medicaid Services (CMS) has instituted big changes in its enrollment procedures that could have a major impact on physician groups that fail to comply with CMS' new requirements. First, tick ... tick ... tick ... time is quickly running out on the chance to obtain, and implement into the flow of your practice, a National Provider Identification number (NPI). The bad news is that the requirement to get an NPI is statutory, meaning it's not going to go away. Second, CMS revamped its Medicare provider enrollment processes in an attempt to reduce enrollment application processing delays. Unfortunately, rather than expedite the enrollment process, CMS' new regulations had the over-all effect of causing even more delays and backlogs in the enrollment process. Providers who do not have an NPI by the required deadline risk potential compliance penalties and payment delays. Therefore, not having an NPI or a Medicare Provider Number can have serious consequences on providers' ability to provide care as well as their bottom line (think cash flow!).

Probability Discounting of Gains and Losses: Implications for Risk Attitudes and Impulsivity

ERIC Educational Resources Information Center

Shead, N. Will; Hodgins, David C.

2009-01-01

Sixty college students performed three discounting tasks: probability discounting of gains, probability discounting of losses, and delay discounting of gains. Each task used an adjusting-amount procedure, and participants' choices affected the amount and timing of their remuneration for participating. Both group and individual discounting…

Assessing Self-Control Training in Children with Attention Deficit Hyperactivity Disorder

ERIC Educational Resources Information Center

Bloh, Christopher

2009-01-01

This study examined the use of a progressive delay procedure with and without a concurrent activity to teach self-control to children with attention deficit hyperactivity disorder. Three participants were initially required to wait progressively longer periods of time for access to preferred edible reinforcers. After demonstrating this…

Laparoscopic transverse rectus abdominus flap delay for autogenous breast reconstruction.

PubMed

Kaddoura, I L; Khoury, G S

1998-01-01

Laparoscopic ligation of the deep and superficial inferior epigastric vessels was done for ten mastectomized patients who elected to have autogenous reconstruction of their breast. All these patients had at least one indication for the delay which included obesity, smoking, or requirement of a large volume of tissue for their reconstruction. The procedure did not add any morbidity or mortality to our patients and was found to be comparable to the "open" delay in preventing partial tissue loss in all but two patients. We describe the use of a minimally invasive procedure to augment the deep superior epigastric pedicled blood supply for the future transverse rectus abdominus flap. We have found in laparoscopic delay a safe, short procedure that is useful in high risk patients who choose the option of autologous breast reconstruction.

Improved Stability and Stabilization Results for Stochastic Synchronization of Continuous-Time Semi-Markovian Jump Neural Networks With Time-Varying Delay.

PubMed

Wei, Yanling; Park, Ju H; Karimi, Hamid Reza; Tian, Yu-Chu; Jung, Hoyoul; Yanling Wei; Park, Ju H; Karimi, Hamid Reza; Yu-Chu Tian; Hoyoul Jung; Tian, Yu-Chu; Wei, Yanling; Jung, Hoyoul; Karimi, Hamid Reza; Park, Ju H

2018-06-01

Continuous-time semi-Markovian jump neural networks (semi-MJNNs) are those MJNNs whose transition rates are not constant but depend on the random sojourn time. Addressing stochastic synchronization of semi-MJNNs with time-varying delay, an improved stochastic stability criterion is derived in this paper to guarantee stochastic synchronization of the response systems with the drive systems. This is achieved through constructing a semi-Markovian Lyapunov-Krasovskii functional together as well as making use of a novel integral inequality and the characteristics of cumulative distribution functions. Then, with a linearization procedure, controller synthesis is carried out for stochastic synchronization of the drive-response systems. The desired state-feedback controller gains can be determined by solving a linear matrix inequality-based optimization problem. Simulation studies are carried out to demonstrate the effectiveness and less conservatism of the presented approach.

Increasing spontaneous language in three autistic children.

PubMed Central

Matson, J L; Sevin, J A; Fridley, D; Love, S R

1990-01-01

A time delay procedure was used to increase spontaneous verbalizations of 3 autistic children. Multiple baseline across behaviors designs were used with target responses, selected via a social validation procedure, of two spontaneous responses ("please" and "thank you") and one verbally prompted response ("you're welcome"). The results indicate gains across target behaviors for all children, with occurrence across other stimuli and settings. These gains were validated socially with 10 adults. Furthermore, increases in appropriate language had no effect on levels of inappropriate speech. PMID:2373659

75 FR 32273 - Representation Election Procedure

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-08

... NATIONAL MEDIATION BOARD 29 CFR Parts 1202 and 1206 [Docket No. C-6964] RIN 3140-ZA00 Representation Election Procedure AGENCY: National Mediation Board. ACTION: Final rule; delay of effective date. SUMMARY: The National Mediation Board (NMB) is delaying the effective date of its rule regarding...

Signal functions in delayed reinforcement

PubMed Central

Lattal, Kennon A.

1984-01-01

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

Early prophylactic autogenous bone grafting in type III open tibial fractures.

PubMed

Kesemenli, Cumhur C; Kapukaya, Ahmet; Subaşi, Mehmet; Arslan, Huseyin; Necmioğlu, Serdar; Kayikçi, Cuma

2004-08-01

The authors report the results achieved in patients with type III open tibial fractures who underwent primary autogenous bone grafting at the time of debridement and skeletal stabilisation. Twenty patients with a mean age of 35.8 years (range, 24-55) were treated between 1996 and 1999. Eight fractures were type IIIA, 11 were type IIIB, and 1 was type IIIC. At the index procedure, wound debridement, external fixation and autogenous bone grafting with bone coverage were achieved. The mean follow-up period was 46 months (range, 34-55). The mean time to fixator removal was 21 weeks (range, 14-35), and the mean time to union was 28 weeks (range, 19-45). Skin coverage was achieved by a myocutaneous flap in 2 patients, late primary closure in 4, and split skin grafting in 14. One (5%) of the patients experienced delayed union, and 1 (5%) developed infection. In tibial type III open fractures, skin coverage may be delayed, using the surrounding soft tissue to cover any exposed bone after thorough débridement and wound cleansing. Primary prophylactic bone grafting performed at the same time reduces the rate of delayed union, shortens the time to union, and does not increase the infection rate.

The medical and economic consequences of automation in bacteriology: a case study in a French university hospital.

PubMed

Sailly, J C; Lebrun, T; Vincent, P; Eeckhoudt, L; Izard, D; Leclerc, H; Arbon, G; Hassoun, A

1985-01-01

In a bacteriology laboratory where automated and non-automated procedures co-existed during the study period (1 year), patients were randomly assigned to each type of procedure and we observed the physicians behaviour as well as patients well-being in a surgical service using the results from the laboratory. Contrary to our expectations, the reduction in the time delay necessary to obtain information did not alter either the prescribing behaviour of physicians nor the welfare of patients. Besides, the gain in time was significantly lower than expected. We also discuss in detail the meaning and relevance of the results.

Massed Trials versus Trials Embedded into Game Play: Child Outcomes and Preference

ERIC Educational Resources Information Center

Ledford, Jennifer R.; Chazin, Kate T.; Harbin, Emilee R.; Ward, Sarah E.

2017-01-01

Limited data are available regarding how response prompting procedures should be used in early childhood settings. The purpose of this study was to compare the efficiency of progressive time delay instruction presented via two trial arrangements: massed and embedded. During massed trial sessions, a short instructional session was conducted,…

Addition of Functional Content during Core Content Instruction with Students with Moderate Disabilities

ERIC Educational Resources Information Center

Collins, Belva C.; Hager, Karen L.; Galloway, Carey Creech

2011-01-01

The purpose of this investigation was to add functional content during core content instruction of language arts, science, and math. The investigation involved three middle school students with moderate disabilities who participated in the state's alternate assessment. During instruction using a constant time delay procedure to teach required…

47 CFR 27.1252 - Involuntary Relocation Procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... costs, including all engineering, equipment, site and FCC fees, as well as any legitimate and prudent... measured by the percent of time the bit error rate (BER) exceeds a desired value, and for analog or digital video transmissions, it is measured by whether the end-to-end transmission delay is within the required...

Teaching Principles of Heredity to High School Students with Moderate and Severe Disabilities

ERIC Educational Resources Information Center

Riggs, Leah; Collins, Belva C.; Kleinert, Harold; Knight, Victoria F.

2013-01-01

This investigation focused on the systematic instruction of a science skill from the core content standards in accordance with the Kentucky Alternate Assessment for students with moderate and severe disabilities (MSD). Specifically, this study examined the effectiveness of using a constant time delay procedure with multiple exemplars in teaching…

Video Modeling to Teach Social Safety Skills to Young Adults with Intellectual Disability

ERIC Educational Resources Information Center

Spivey, Corrine E.; Mechling, Linda C.

2016-01-01

This study evaluated the effectiveness of video modeling with a constant time delay procedure to teach social safety skills to three young women with intellectual disability. A multiple probe design across three social safety skills (responding to strangers who: requested personal information; requested money; and entered the participant's…

27 CFR 70.75 - Jeopardy assessment of alcohol, tobacco, and firearms taxes.

Code of Federal Regulations, 2010 CFR

2010-04-01

... AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURES AND PRACTICES... jeopardized by delay, the appropriate TTB officer must, whether or not the time otherwise prescribed by law... interest, additional amounts and additions to the tax provided by law. An appropriate TTB officer will make...

10 CFR 436.16 - Establishing non-fuel and non-water cost categories.

Code of Federal Regulations, 2011 CFR

2011-01-01

... PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.16 Establishing non-fuel... discount rate and escalation rate assumptions under § 436.14. When recurring costs begin to accrue at a later time, subtract the present value of recurring costs over the delay, calculated using the...

Acquisition of Content Area Vocabulary for Students with Learning Disabilities.

ERIC Educational Resources Information Center

Keel, Marie C.; Slaton, Deborah Bott; Blackhurt, A. Edward

2001-01-01

This study compared effects of two variations of the constant-time-delay (CTD) procedure on the observational learning of content area vocabulary by seven primary grade students with learning disabilities in a small group instructional setting. Both conditions (every student writes all words or only target student writes) were equally effective…

STD Installation and Maintenance Procedures. Satellite Technology DEmonstration, Technical Report No. 0421.

ERIC Educational Resources Information Center

Lane, Billy D.

The ground terminals for the Satellite Technology Demonstration were more expensive to install than was anticipated because crews forced to make numerous visits to each site. Delays were caused by delinquent deliveries and by malfunctions in some of the subsystems. Insufficient time was allowed for trouble shooting, and consequently, additional…

Influence of Timing of Delayed Hard Palate Closure on Articulation Skills in 3-Year-Old Danish Children with Unilateral Cleft Lip and Palate

ERIC Educational Resources Information Center

Willadsen, Elisabeth; Boers, Maria; Schöps, Antje; Kisling-Møller, Mia; Nielsen, Joan Bogh; Jørgensen, Line Dahl; Andersen, Mikael; Bolund, Stig; Andersen, Helene Søgaard

2018-01-01

Background: Differing results regarding articulation skills in young children with cleft palate (CP) have been reported and often interpreted as a consequence of different surgical protocols. Aims: To assess the influence of different timing of hard palate closure in a two-stage procedure on articulation skills in 3-year-olds born with unilateral…

Accounting for exhaust gas transport dynamics in instantaneous emission models via smooth transition regression.

PubMed

Kamarianakis, Yiannis; Gao, H Oliver

2010-02-15

Collecting and analyzing high frequency emission measurements has become very usual during the past decade as significantly more information with respect to formation conditions can be collected than from regulated bag measurements. A challenging issue for researchers is the accurate time-alignment between tailpipe measurements and engine operating variables. An alignment procedure should take into account both the reaction time of the analyzers and the dynamics of gas transport in the exhaust and measurement systems. This paper discusses a statistical modeling framework that compensates for variable exhaust transport delay while relating tailpipe measurements with engine operating covariates. Specifically it is shown that some variants of the smooth transition regression model allow for transport delays that vary smoothly as functions of the exhaust flow rate. These functions are characterized by a pair of coefficients that can be estimated via a least-squares procedure. The proposed models can be adapted to encompass inherent nonlinearities that were implicit in previous instantaneous emissions modeling efforts. This article describes the methodology and presents an illustrative application which uses data collected from a diesel bus under real-world driving conditions.

Motivational Control of Impulsive Behavior Interacts with Choice Opportunities

ERIC Educational Resources Information Center

Tanno, Takayuki; Kurashima, Ryo; Watanabe, Shigeru

2011-01-01

Impulsive behavior has been investigated through choice between a smaller/immediate reinforcer and a larger/delayed reinforcer, or through performance on a differential reinforcement of low rate (DRL) schedule. In the present study, we investigated a methodological divergence between these two procedures: in the former procedure, delay is a…

Immediate newborn care practices delay thermoregulation and breastfeeding initiation

PubMed Central

Sobel, Howard L; Silvestre, Maria Asuncion A; Mantaring, Jacinto Blas V; Oliveros, Yolanda E; Nyunt-U, Soe

2011-01-01

Aim A deadly nosocomial outbreak in a Philippine hospital drew nationwide attention to neonatal sepsis. Together with specific infection control measures, interventions that protect newborns against infection-related mortality include drying, skin-to-skin contact, delayed cord clamping, breastfeeding initiation and delayed bathing. This evaluation characterized hospital care in the first hours of life with the intent to drive policy change, strategic planning and hospital reform. Methods Trained physicians observed 481 consecutive deliveries in 51 hospitals using a standardized tool to record practices and timing of immediate newborn care procedures. Results Drying, weighing, eye care and vitamin K injections were performed in more than 90% of newborns. Only 9.6% were allowed skin-to-skin contact. Interventions were inappropriately sequenced, e.g. immediate cord clamping (median 12 sec), delayed drying (96.5%) and early bathing (90.0%). While 68.2% were put to the breast, they were separated two minutes later. Unnecessary suctioning was performed in 94.9%. Doctors trained in neonatal resuscitation were 2.5 (1.1–5.7) times more likely to unnecessarily suction vigorous newborns. Two per cent died and 5.7% developed sepsis/pneumonia. Conclusions This minute-by-minute observational assessment revealed that performance and timing of immediate newborn care interventions are below WHO standards and deprive newborns of basic protections against infection and death. PMID:21375583

Assessment of progressively delayed prompts on guided skill learning in rats.

PubMed

Reid, Alliston K; Futch, Sara E; Ball, Katherine M; Knight, Aubrey G; Tucker, Martha

2017-03-01

We examined the controlling factors that allow a prompted skill to become autonomous in a discrete-trials implementation of Touchette's (1971) progressively delayed prompting procedure, but our subjects were rats rather than children with disabilities. Our prompted skill was a left-right lever-press sequence guided by two panel lights. We manipulated (a) the effectiveness of the guiding lights prompt and (b) the presence or absence of a progressively delayed prompt in four groups of rats. The less effective prompt yielded greater autonomy than the more effective prompt. The ability of the progressively delayed prompt procedure to produce behavioral autonomy depended upon characteristics of the obtained delay (trial duration) rather than on the pending prompt. Sequence accuracy was reliably higher in unprompted trials than in prompted trials, and this difference was maintained in the 2 groups that received no prompts but yielded equivalent trial durations. Overall sequence accuracy decreased systematically as trial duration increased. Shorter trials and their greater accuracy were correlated with higher overall reinforcement rates for faster responding. Waiting for delayed prompts (even if no actual prompt was provided) was associated with lower overall reinforcement rate by decreasing accuracy and by lengthening trials. These findings extend results from previous studies regarding the controlling factors in delayed prompting procedures applied to children with disabilities.

The use of picture prompts and prompt delay to teach receptive labeling.

PubMed

Vedora, Joseph; Barry, Tiffany

2016-12-01

The current study extended research on picture prompts by using them with a progressive prompt delay to teach receptive labeling of pictures to 2 teenagers with autism. The procedure differed from prior research because the auditory stimulus was not presented or was presented only once during the picture-prompt condition. The results indicated that the combination of picture prompts and prompt delay was effective, although 1 participant required a procedural modification. © 2016 Society for the Experimental Analysis of Behavior.

Instrumentation for one-way satellite PTTI applications. [calibration and synchronization of clocks from navigation satellite

NASA Technical Reports Server (NTRS)

Osborne, A. E.

1973-01-01

A review of general principles and operational procedures illustrates how the typical passive user and omni receiving antenna can recover Precise Time and Time Interval (PTTI) information from a low altitude navigation satellite system for clock calibration and synchronization. Detailed discussions of concepts and theory of the receiver design are presented. The importance of RF correlation of the received and local PN encoded sequences is emphasized as a means of reducing delay uncertainties of the instrumentation to values compatible with nanosecond to submicrosecond PTTI objectives. Two receiver configurations were fabricated for use in satellite-to-laboratory experiments. In one receiver the delay-locked loop for PN signals synchronization used a dithered amplitude detection process while the second receiver used a complex sums phase detection method for measurement of delay error. The necessity for compensation of Doppler shift is discussed. Differences in theoretical signal acquisition and tracking performance of the design concepts are noted.

Transient delayed facial nerve palsy after inferior alveolar nerve block anesthesia.

PubMed

Tzermpos, Fotios H; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

2012-01-01

Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution.

Transient Delayed Facial Nerve Palsy After Inferior Alveolar Nerve Block Anesthesia

PubMed Central

Tzermpos, Fotios H.; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

2012-01-01

Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution. PMID:22428971

Interhospital transfer delays emergency abdominal surgery and prolongs stay.

PubMed

Limmer, Alexandra M; Edye, Michael B

2017-11-01

Interhospital transfer of patients requiring emergency surgery is common practice. It has the potential to delay surgical intervention, increase rate of complications and thus length of hospital stay. A retrospective cohort study was conducted of adult patients who underwent emergency surgery for abdominal pain at a large metropolitan hospital in New South Wales (Hospital A) in 2013. The impact of interhospital transfer on time to surgical intervention, post-operative length of stay and overall length of stay was assessed. Of the 910 adult patients who underwent emergency surgery for abdominal pain at Hospital A in 2013, 31.9% (n = 290) were transferred by road ambulance from a local district hospital (Hospital B). The leading surgical procedures performed were appendicectomy (n = 299, 32.9%), cholecystectomy (n = 174, 19.1%), gastrointestinal endoscopy (n = 95, 10.4%), cystoscopy (n = 86, 9.5%), hernia repair (n = 45, 4.9%), salpingectomy (n = 19, 2.1%) and oversewing of perforated peptic ulcer (n = 13, 1.4%). Overall, interhospital transfer (n = 290, 31.9%) was associated with increases in mean time to surgical intervention (14.2 h, P < 0.001), post-operative length of stay (1.1 days, P = 0.001) and overall length of stay (1.6 days, P < 0.001). Delayed surgical intervention was observed across all procedure types except surgery for perforated peptic ulcer, where transferred patients underwent surgery within a comparable timeframe to direct admissions. Interhospital transfer delays surgical intervention and increases length of hospital stay. This mandates attention due to the implications for patient outcomes and added burden to the healthcare system. The system did, however, show capability to appropriately expedite surgery for acutely life-threatening cases. © 2016 Royal Australasian College of Surgeons.

Delayed Slater determinant update algorithms for high efficiency quantum Monte Carlo

DOE PAGES

McDaniel, Tyler; D’Azevedo, Ed F.; Li, Ying Wai; ...

2017-11-07

Within ab initio Quantum Monte Carlo simulations, the leading numerical cost for large systems is the computation of the values of the Slater determinants in the trial wavefunction. Each Monte Carlo step requires finding the determinant of a dense matrix. This is most commonly iteratively evaluated using a rank-1 Sherman-Morrison updating scheme to avoid repeated explicit calculation of the inverse. The overall computational cost is therefore formally cubic in the number of electrons or matrix size. To improve the numerical efficiency of this procedure, we propose a novel multiple rank delayed update scheme. This strategy enables probability evaluation with applicationmore » of accepted moves to the matrices delayed until after a predetermined number of moves, K. The accepted events are then applied to the matrices en bloc with enhanced arithmetic intensity and computational efficiency via matrix-matrix operations instead of matrix-vector operations. Here this procedure does not change the underlying Monte Carlo sampling or its statistical efficiency. For calculations on large systems and algorithms such as diffusion Monte Carlo where the acceptance ratio is high, order of magnitude improvements in the update time can be obtained on both multi- core CPUs and GPUs.« less

Delayed Slater determinant update algorithms for high efficiency quantum Monte Carlo

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

McDaniel, Tyler; D’Azevedo, Ed F.; Li, Ying Wai

Within ab initio Quantum Monte Carlo simulations, the leading numerical cost for large systems is the computation of the values of the Slater determinants in the trial wavefunction. Each Monte Carlo step requires finding the determinant of a dense matrix. This is most commonly iteratively evaluated using a rank-1 Sherman-Morrison updating scheme to avoid repeated explicit calculation of the inverse. The overall computational cost is therefore formally cubic in the number of electrons or matrix size. To improve the numerical efficiency of this procedure, we propose a novel multiple rank delayed update scheme. This strategy enables probability evaluation with applicationmore » of accepted moves to the matrices delayed until after a predetermined number of moves, K. The accepted events are then applied to the matrices en bloc with enhanced arithmetic intensity and computational efficiency via matrix-matrix operations instead of matrix-vector operations. Here this procedure does not change the underlying Monte Carlo sampling or its statistical efficiency. For calculations on large systems and algorithms such as diffusion Monte Carlo where the acceptance ratio is high, order of magnitude improvements in the update time can be obtained on both multi- core CPUs and GPUs.« less

Delayed Slater determinant update algorithms for high efficiency quantum Monte Carlo.

PubMed

McDaniel, T; D'Azevedo, E F; Li, Y W; Wong, K; Kent, P R C

2017-11-07

Within ab initio Quantum Monte Carlo simulations, the leading numerical cost for large systems is the computation of the values of the Slater determinants in the trial wavefunction. Each Monte Carlo step requires finding the determinant of a dense matrix. This is most commonly iteratively evaluated using a rank-1 Sherman-Morrison updating scheme to avoid repeated explicit calculation of the inverse. The overall computational cost is, therefore, formally cubic in the number of electrons or matrix size. To improve the numerical efficiency of this procedure, we propose a novel multiple rank delayed update scheme. This strategy enables probability evaluation with an application of accepted moves to the matrices delayed until after a predetermined number of moves, K. The accepted events are then applied to the matrices en bloc with enhanced arithmetic intensity and computational efficiency via matrix-matrix operations instead of matrix-vector operations. This procedure does not change the underlying Monte Carlo sampling or its statistical efficiency. For calculations on large systems and algorithms such as diffusion Monte Carlo, where the acceptance ratio is high, order of magnitude improvements in the update time can be obtained on both multi-core central processing units and graphical processing units.

Delayed Slater determinant update algorithms for high efficiency quantum Monte Carlo

NASA Astrophysics Data System (ADS)

McDaniel, T.; D'Azevedo, E. F.; Li, Y. W.; Wong, K.; Kent, P. R. C.

2017-11-01

Within ab initio Quantum Monte Carlo simulations, the leading numerical cost for large systems is the computation of the values of the Slater determinants in the trial wavefunction. Each Monte Carlo step requires finding the determinant of a dense matrix. This is most commonly iteratively evaluated using a rank-1 Sherman-Morrison updating scheme to avoid repeated explicit calculation of the inverse. The overall computational cost is, therefore, formally cubic in the number of electrons or matrix size. To improve the numerical efficiency of this procedure, we propose a novel multiple rank delayed update scheme. This strategy enables probability evaluation with an application of accepted moves to the matrices delayed until after a predetermined number of moves, K. The accepted events are then applied to the matrices en bloc with enhanced arithmetic intensity and computational efficiency via matrix-matrix operations instead of matrix-vector operations. This procedure does not change the underlying Monte Carlo sampling or its statistical efficiency. For calculations on large systems and algorithms such as diffusion Monte Carlo, where the acceptance ratio is high, order of magnitude improvements in the update time can be obtained on both multi-core central processing units and graphical processing units.

Atmospheric oscillations comparison on long term tropospheric delay time series derived from ray-tracing and GPS

NASA Astrophysics Data System (ADS)

Nikolaidou, Thalia; Santos, Marcelo

2017-04-01

The caused time delay induced by the atmosphere on the GNSS signals (NAD), depends primarily on the amount of atmosphere the signal traverses till it reaches to the Earth's surface and can exceed t 20 m for low elevation angles (around 3 degrees). For a particular ray i.e. satellite/quasar-antenna link, the delay depends on the atmospheric parameters of total pressure, temperature, and the partial pressure of water vapor. Because of that, numerical weather models (NWM) have already proven beneficial for atmospheric modelling and geodesy. By direct raytracing, inside NWM, the VMF1 and the University of New Brunswick VMF1 (UNB-VMF1) (Urquhart et al. 2011), access the 3D variation of the meteorological parameters that determine the delay thus being the state-the-art mapping functions used today. The raytracing procedure is capable of providing NADs delays for any point on the Earth's surface. In this study we study the impact of regional numerical weather models, with high spatial and temporal resolution, namely 25km and 6h. These models outweigh the currently used NWM by having about 2.6 times better spatial resolution. Raytracing through such NWM, using the independent raytracing algorithm develop at UNB (Nievinski, 2009), we acquire superior quality NADs with regional application. We ray-trace for the International GNSS service (IGS) network stations for a time span of 11 years. Benchmarking against the IGS troposphere product is performed to access the accuracy of our results. A periodicity analysis is conducted to examine the signature of atmospheric oscillations on the NAD time series. In order to recognize the NAD periodicities, we compared our product against the GPS-derived IGS troposphere product. Systematic effects within each single technique are identified and long-term NAD stability is accessed.

Impact of Smart Board Technology: An Investigation of Sight Word Reading and Observational Learning

ERIC Educational Resources Information Center

Mechling, Linda C.; Gast, David L.; Krupa, Kristin

2007-01-01

The effects of SMART Board technology, an interactive electronic whiteboard, and a 3s constant time delay (CTD) procedure was evaluated for teaching sight word reading to students with moderate intellectual disabilties within a small group arrangment. A multiple probe design across three word sets and replicated with three students was used to…

Facial palsy after dental procedures - Is viral reactivation responsible?

PubMed

Gaudin, Robert A; Remenschneider, Aaron K; Phillips, Katie; Knipfer, Christian; Smeets, Ralf; Heiland, Max; Hadlock, Tessa A

2017-01-01

Herpes labialis viral reactivation has been reported following dental procedures, but the incidence, characteristics and outcomes of delayed peripheral facial nerve palsy following dental work is poorly understood. Herein we describe the unique features of delayed facial paresis following dental procedures. An institutional retrospective review was performed to identify patients diagnosed with delayed facial nerve palsy within 30 days of dental manipulation. Demographics, prodromal signs and symptoms, initial medical treatment and outcomes were assessed. Of 2471 patients with facial palsy, 16 (0.7%) had delayed facial paresis following ipsilateral dental procedures. Average age at presentation was 44 yrs and 56% (9/16) were female. Clinical evaluation was consistent with Bell's palsy in 14 (88%) and Ramsay-Hunt syndrome in 2 patients (12%). Patients developed facial paresis an average of 3.9 days after the dental procedure, with all individuals developing a flaccid paralysis (House Brackmann (HB) grade VI) during the acute stage. 50% of patients developed persistent facial palsy in the form of non-flaccid facial paralysis (HBIII-IV). Facial palsy, like herpes labialis, can occur in the days following dental procedures and may also be related to viral reactivation. In this small cohort, long-term facial outcomes appear worse than for spontaneous Bell's palsy. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

An institutional study of time delays for symptomatic carotid endarterectomy.

PubMed

Charbonneau, Philippe; Bonaventure, Paule Lessard; Drudi, Laura M; Beaudoin, Nathalie; Blair, Jean-François; Elkouri, Stéphane

2016-12-01

The aim of this study was to assess time delays between first cerebrovascular symptoms and carotid endarterectomy (CEA) at a single center and to systematically evaluate causes of these delays. Consecutive adult patients who underwent CEAs between January 2010 and September 2011 at a single university-affiliated center (Centre Hospitalier de l'Université Montréal-Hôtel-Dieu Hospital, Montreal) were identified from a clinical database and operative records. Covariates of interest were extracted from electronic medical records. Timing and nature of the first cerebrovascular symptoms were also documented. The first medical contact and pathway of referral were also assessed. When possible, the ABCD 2 score (age, blood pressure, clinical features, duration of symptoms, and diabetes) was calculated to calculate further risk of stroke. The nonparametric Wilcoxon test was used to assess differences in time intervals between two variables. The Kruskal-Wallis test was used to assess differences in time intervals in comparing more than two variables. A multivariate linear regression analysis was performed using covariates that were determined to be statistically significant in our sensitivity analyses. The cohort consisted of 111 patients with documented symptomatic carotid stenosis undergoing surgical intervention. Thirty-nine percent of all patients were operated on within 2 weeks from the first cerebrovascular symptoms. The median time between the occurrence of the first neurologic symptom and the CEA procedure was 25 (interquartile range [IQR], 11-85) days. The patient-dependent delay, defined as the median delay between the first neurologic symptom and the first medical contact, was 1 (IQR, 0-14) day. The medical-dependent delay was defined as the time interval between the first medical contact and CEA. This included the delay between the first medical contact and the request for surgery consultation (median, 3 [IQR, 1-10] days). The multivariate regression model demonstrated that the emergency physician as referral source (P = .0002) was statistically significant for reducing CEA delay. Patients who were investigated as an outpatient (P = .02), first medical contact with a general practitioner (P = .0002), and hospital center I as referral center (P = .045) were also found to be statistically significant to extend CEA delay when the model was adjusted over all covariates. In this center, there was no correlation between ABCD 2 risk score and waiting time for surgery. The majority of our cohort falls short of the recommended 2-week interval to perform CEA. Factors contributing to reduced CEA delay were presentation to an emergency department, in-patient investigations, and a stroke center where a vascular surgeon is available. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Rapid diagnosis of tinea incognito using handheld reflectance confocal microscopy: a paradigm shift in dermatology?

PubMed

Navarrete-Dechent, Cristián; Bajaj, Shirin; Marghoob, Ashfaq A; Marchetti, Michael A

2015-06-01

Dermatophytoses are common skin infections. Traditional diagnostic tests such as skin scrapings for light microscopy examination, fungal cultures and biopsies remain imperfect due to false-negative test results, cost, time required to perform the procedure, time delays in test results and/or a requirement for an invasive procedure. Herein, we present a case of an 80-year-old female whose tinea incognito was non-invasively diagnosed within seconds using handheld reflectance confocal microscopy (RCM). As non-invasive skin imaging continues to improve, we expect light-based office microscopy to be replaced with technologies such as RCM, which has multiple and continually expanding diagnostic applications. © 2015 Blackwell Verlag GmbH.

Local flow management/profile descent algorithm. Fuel-efficient, time-controlled profiles for the NASA TSRV airplane

NASA Technical Reports Server (NTRS)

Groce, J. L.; Izumi, K. H.; Markham, C. H.; Schwab, R. W.; Thompson, J. L.

1986-01-01

The Local Flow Management/Profile Descent (LFM/PD) algorithm designed for the NASA Transport System Research Vehicle program is described. The algorithm provides fuel-efficient altitude and airspeed profiles consistent with ATC restrictions in a time-based metering environment over a fixed ground track. The model design constraints include accommodation of both published profile descent procedures and unpublished profile descents, incorporation of fuel efficiency as a flight profile criterion, operation within the performance capabilities of the Boeing 737-100 airplane with JT8D-7 engines, and conformity to standard air traffic navigation and control procedures. Holding and path stretching capabilities are included for long delay situations.

Irreparable Radial Nerve Palsy Due to Delayed Diagnostic Management of a Giant Lipoma at the Proximal Forearm Resulting in a Triple Tendon Transfer Procedure: Case report and Brief Review of Literature

PubMed Central

Schmidt, Ingo

2017-01-01

Background: Non-traumatic radial nerve palsy (RNP) caused by local tumors is a rare and uncommon entity. Methods: A 62-year-old female presented with a left non-traumatic RNP, initially starting with weakness only. It was caused by a benign giant lipoma at the proximal forearm that was misdiagnosed over a period of 2 years. The slowly growth of the tumor led to an irreparable overstretching-related partial nerve disruption. For functional recovery of the patient, a triple tendon transfer procedure had to be performed. Results: Four months after surgery, the patient was completely able to perform her activities of daily living again. At the 10-months follow-up, strength of wrist extension, thumb's extension and abduction, and long fingers II-V extension had all improved to grade 4 in Medical Research Council scale (0-5). In order to restore motion, the patient reported that she would undergo the same triple tendon transfer procedure a second time where necessary. Due to the initially misdiagnosed tumor, there was an overall delayed duration of time for functional recovery of the patient. Conclusion: The triple tendon transfer procedure offers a useful and reliable method to restore functionality for patients sustaining irreparable RNP. However, it must be noted critically with our patient that this procedure probably would have been avoided. Initially, there was weakness only by entrapment of the radial nerve. RNP caused by local tumors are uncommon but known from the literature, and so it should be considered generally in differential diagnosis of non-traumatic RNP. PMID:28979592

Methods of measurement for semiconductor materials, process control, and devices

NASA Technical Reports Server (NTRS)

Bullis, W. M. (Editor)

1972-01-01

Significant accomplishments include development of a procedure to correct for the substantial differences of transistor delay time as measured with different instruments or with the same instrument at different frequencies; association of infrared response spectra of poor quality germanium gamma ray detectors with spectra of detectors fabricated from portions of a good crystal that had been degraded in known ways; and confirmation of the excellent quality and cosmetic appearance of ultrasonic bonds made with aluminum ribbon wire. Work is continuing on measurement of resistivity of semiconductor crystals; study of gold-doped silicon, development of the infrared response technique; evaluation of wire bonds and die attachment; and measurement of thermal properties of semiconductor devices, delay time and related carrier transport properties in junction devices, and noise properties of microwave diodes.

Determination of differential arrival times by cross-correlating worldwide seismological data

NASA Astrophysics Data System (ADS)

Godano, M.; Nolet, G.; Zaroli, C.

2012-12-01

Cross-correlation delays are the preferred body wave observables in global tomography. Heterogeneity is the main factor influencing delay times found by cross-correlation. Not only the waveform, but also the arrival time itself is affected by differences in seismic velocity encountered along the way. An accurate method for estimating differential times of seismic arrivals across a regional array by cross-correlation was developed by VanDecar and Crosson [1990]. For the estimation of global travel time delays in different frequency bands, Sigloch and Nolet [2006] developed a method for the estimation of body wave delays using a matched filter, which requires the separate estimation of the source time function. Sigloch et al. [2008] found that waveforms often cluster in and opposite the direction of rupture propagation on the fault, confirming that the directivity effect is a major factor in shaping the waveform of large events. We propose a generalization of the VanDecar-Crosson method to which we add a correction for the directivity effect in the seismological data. The new method allows large events to be treated without the need to estimate the source time function for the computation of a matched synthetic waveform. The procedure consists in (1) the detection of the directivity effect in the data and the determination of a rupture model (unilateral or bilateral) explaining the differences in pulse duration among the stations, (2) the determination of an apparent fault rupture length explaining the pulse durations, (3) the removal of the delay due to the directivity effect in the pulse duration , by stretching or contracting the seismograms for directive and anti-directive stations respectively and (4) the application of a generalized VanDecar and Crosson method using only delays between pairs of stations that have an acceptable correlation coefficient. We validate our method by performing tests on synthetic data. Results show that the error between theoretical and measured differential arrival time are significantly reduced for the corrected data. We illustrate our method on data from several real earthquakes.

Factors associated with delayed bleeding after resection of large nonpedunculated colorectal polyps.

PubMed

Elliott, Timothy R; Tsiamoulos, Zacharias P; Thomas-Gibson, Siwan; Suzuki, Noriko; Bourikas, Leonidas A; Hart, Ailsa; Bassett, Paul; Saunders, Brian P

2018-04-06

 Delayed bleeding is the most common significant complication after piecemeal endoscopic mucosal resection (p-EMR) of large nonpedunculated colorectal polyps (NPCPs). Risk factors for delayed bleeding are incompletely defined. We aimed to determine risk factors for delayed bleeding following p-EMR.  Data were analyzed from a prospective tertiary center audit of patients with NPCPs ≥ 20 mm who underwent p-EMR between 2010 and 2012. Patient, polyp, and procedure-related data were collected. Four post p-EMR defect factors were evaluated for interobserver agreement and included in analysis. Delayed bleeding severity was reported in accordance with guidelines. Predictors of bleeding were identified.  Delayed bleeding requiring hospitalization occurred after 22 of 330 procedures (6.7 %). A total of 11 patients required blood transfusion; of these, 4 underwent urgent colonoscopy, 1 underwent radiological embolization, and 1 required surgery. Interobserver agreement for identification of the four post p-EMR defect factors was moderate (kappa range 0.52 - 0.57). Factors associated with delayed bleeding were visible muscle fibers ( P  = 0.03) and the presence of a "cherry red spot" ( P  = 0.05) in the post p-EMR defect. Factors not associated with delayed bleeding were American Association of Anesthesiologists class, aspirin use, polyp size, site, and use of argon plasma coagulation.  Visible muscle fibers and the presence of a "cherry red spot" in the resection defect were associated with delayed bleeding after p-EMR. These findings suggest evaluation and photodocumentation of the post p-EMR defect is important and, when considered alongside other patient and procedural factors, may help to reduce the incidence and severity of delayed bleeding. © Georg Thieme Verlag KG Stuttgart · New York.

[Impact of Lean methodology to improve care processes and levels of satisfaction in patient care in a clinical laboratory].

PubMed

Morón-Castañeda, L H; Useche-Bernal, A; Morales-Reyes, O L; Mojica-Figueroa, I L; Palacios-Carlos, A; Ardila-Gómez, C E; Parra-Ardila, M V; Martínez-Nieto, O; Sarmiento-Echeverri, N; Rodríguez, C A; Alvarado-Heine, C; Isaza-Ruget, M A

2015-01-01

The application of the Lean methodology in health institutions is an effective tool to improve the capacity and workflow, as well as to increase the level of satisfaction of patients and employees. To optimise the time of outpatient care in a clinical laboratory, by implementing a methodology based on the organisation of operational procedures to improve user satisfaction and reduce the number of complaints for delays in care. A quasi-experimental before and after study was conducted between October 2011 to September 2012. XBar and S charts were used to observe the mean service times and standard deviation. The user satisfaction was assessed using service questionnaires. A reduction of 17 minutes was observed in the time of patient care from arrival to leaving the laboratory, and a decrease of 60% in complaints of delay in care. Despite the high staff turnover and 38% increase in the number of patients seen, a culture of empowerment and continuous improvement was acquired, as well as greater efficiency and productivity in the care process, which was reflected by maintaining standards 12 months after implementation. Lean is a viable methodology for clinical laboratory procedures, improving their efficiency and effectiveness. Copyright © 2015 SECA. Published by Elsevier Espana. All rights reserved.

How long do the short-term violent video game effects last?

PubMed

Barlett, Christopher; Branch, Omar; Rodeheffer, Christopher; Harris, Richard

2009-01-01

How long do the effects of the initial short-term increase in aggression and physiological arousal last after violent video game play? Study 1 (N=91) had participants complete pre- and postvideo game measures of aggressive thoughts, aggressive feelings, and heart rate. Then, participants completed Time 3 measures after 4 min or 9 min of delay. Study 2 employed a similar procedure, but had participants (N=91) complete the hot sauce paradigm to assess aggressive behavior after a 0, 5, or 10 min delay. First, results indicated that aggressive feelings, aggressive thoughts, aggressive behavior, and heart rate initially increased after violent video game play. Second, results of the delay condition revealed that the increase in aggressive feelings and aggressive thoughts lasted less than 4 min, whereas heart rate and aggressive behavior lasted 4-9 min. Copyright 2009 Wiley-Liss, Inc.

Tolerance to cocaine's effects on schedule-controlled behavior: role of delay between pause-ending responses and reinforcement.

PubMed

Macaskill, Anne C; Branch, Marc N

2012-01-01

The schedule of reinforcement under which behavior is maintained is an important contributor to whether tolerance to the behavioral effects of cocaine develops. Schedule parameter value (for example, fixed-ratio size) has been shown to affect the development of tolerance under some schedule types but not others, but the specific procedural variables causing this effect remain to be identified. To date, schedule-parameter-related tolerance has developed when a longer pause after reinforcement does not lead to a shorter delay between the response that ends the pause and reinforcement. The current study investigated the importance of this variable in pigeons using a multiple chained Fixed-Ratio 1, Fixed-Time x schedule, in which the first key peck in a trial produced a stimulus change and initiated a delay at the end of which food was presented regardless of whether or not additional pecks were made during the delay. Dose-response curves were assessed before, during and after chronic (daily) administration of cocaine. Tolerance to the pause-increasing effects of cocaine occurred to a similar degree regardless of the scheduled time between the end of the pause and reinforcement. Therefore, the relationship between pause length and delay to reinforcement does not provide an explanation for schedule-parameter-related tolerance. Copyright © 2011 Elsevier Inc. All rights reserved.

Development and validation of a screening procedure to identify speech-language delay in toddlers with cleft palate.

PubMed

Jørgensen, Line Dahl; Willadsen, Elisabeth

2017-01-01

The purpose of this study was to develop and validate a clinically useful speech-language screening procedure for young children with cleft palate ± cleft lip (CP) to identify those in need of speech-language intervention. Twenty-two children with CP were assigned to a +/- need for intervention conditions based on assessment of consonant inventory using a real-time listening procedure in combination with parent-reported expressive vocabulary. These measures allowed evaluation of early speech-language skills found to correlate significantly with later speech-language performance in longitudinal studies of children with CP. The external validity of this screening procedure was evaluated by comparing the +/- need for intervention assignment determined by the screening procedure to experienced speech-language pathologist (SLP)s' clinical judgement of whether or not a child needed early intervention. The results of real-time listening assessment showed good-excellent inter-rater agreement on different consonant inventory measures. Furthermore, there was almost perfect agreement between the children selected for intervention with the screening procedure and the clinical judgement of experienced SLPs indicate that the screening procedure is a valid way of identifying children with CP who need early intervention.

Medical Data Management in Time-Sharing: Findings of the DIRAC Project.

ERIC Educational Resources Information Center

Ludwig, Herbert; Vallee, Jacques

In terms of examples drawn from clinical and research data files, one of the objectives of this study is to illustrate several factors that have combined to delay the implementation of medical data bases. A primary factor has been inherent in the design of computer software. The languages currently on the market are procedural in nature: they…

Rapid Acquisition of Choice and Timing and the Provenance of the Terminal-Link Effect

ERIC Educational Resources Information Center

Kyonka, Elizabeth G. E.; Grace, Randolph C.

2010-01-01

Eight pigeons responded in a concurrent-chains procedure in which terminal-link schedules changed pseudorandomly across sessions. Pairs of terminal-link delays either summed to 15 s or to 45 s. Across sessions, the location of the shorter terminal link changed according to a pseudorandom binary sequence. On some terminal links, food was withheld…

Timeliness and Delay in the Cook County Juvenile Court Child Protection Division. Discussion Paper CS-45.

ERIC Educational Resources Information Center

Merry, Sheila M.; Peters, Clark M.; Goerge, Robert M.; Osuch, Ruth; Minor, Maria; Budde, Stephen

This study suggests that court procedures in Illinois must improve to assure that more children are placed in permanent homes in a timely way. The University of Chicago's Chapin Hall Center for Children examined the timeliness of the Circuit Court of Cook County, Illinois' Child Protection Division in completing the sequence of hearings and…

Effects of a Story-Mapping Procedure Using the iPad on the Comprehension of Narrative Texts by Students with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Browder, Diane M.; Root, Jenny R.; Wood, Leah; Allison, Caryn

2017-01-01

This study investigated the effects of a modified system of least prompts and an electronic story-mapping intervention for elementary students with autism spectrum disorder. Participants were first taught to identify story element definitions using constant time delay. Participants then listened to age-appropriate narrative texts with a…

Helicopter Fatigue Design Guide

DTIC Science & Technology

1983-11-01

for example, glass and carbon fibre reinforced plastics. The general principles behind the substantiation procedures for these materials are...initiating cause of many minor (and sometimes major) cracks that can lead to expensive repair, even though they may not immediately cause a safety...be seen, blade stresses correlated well with both unsteady models. However, push rod loads calculated with the Time Delay Model are much less than

Improving patient access to an interventional US clinic.

PubMed

Steele, Joseph R; Clarke, Ryan K; Terrell, John A; Brightmon, Tonya R

2014-01-01

A continuous quality improvement project was conducted to increase patient access to a neurointerventional ultrasonography (US) clinic. The clinic was experiencing major scheduling delays because of an increasing patient volume. A multidisciplinary team was formed that included schedulers, medical assistants, nurses, technologists, and physicians. The team created an Ishikawa diagram of the possible causes of the long wait time to the next available appointment and developed a flowchart of the steps involved in scheduling and completing a diagnostic US examination and biopsy. The team then implemented a staged intervention that included adjustments to staffing and room use (stage 1); new procedures for scheduling same-day add-on appointments (stage 2); and a lead technician rotation to optimize patient flow, staffing, and workflow (stage 3). Six months after initiation of the intervention, the mean time to the next available appointment had decreased from 25 days at baseline to 1 day, and the number of available daily appointments had increased from 38 to 55. These improvements resulted from a coordinated provider effort and had a net present value of more than $275,000. This project demonstrates that structural changes in staffing, workflow, and room use can substantially reduce scheduling delays for critical imaging procedures. © RSNA, 2014.

Intertrial Sources of Stimulus Control and Delayed Matching-to-Sample Performance in Humans

ERIC Educational Resources Information Center

Williams, Dean C.; Johnston, Mark D.; Saunders, Kathryn J.

2006-01-01

Two experiments compared delayed matching-to-sample (DMTS) accuracy under 2 procedures in adults with mental retardation. In the trial-unique procedure, every trial in a session contained different stimuli. Thus, comparison stimuli that were correct on one trial were never incorrect on other trials in that session (or vice versa). In the 2-sample…

Whipple procedure: a review of a 7-year clinical experience in a referral center for hepatobiliary and pancreas diseases.

PubMed

Saraee, Amir; Vahedian-Ardakani, Jalal; Saraee, Ehsan; Pakzad, Roshanak; Wadji, Massoud Baghai

2015-03-11

Pancreatic cancer is generally found in the older population Pancreaticoduodenectomy seems to be the only way in resolving these resectable tumors. Allen. O Whipple was the first to describe pancreaticoduodenectomy in 1935 as a modified procedure. This article is a case series with respect to the 7-year experience of the Whipple procedure in Firoozgar Teaching Hospital. Patient surgery details were gathered from the surgical records of the operating room and their clinical records from the hospital archives. Data was analyzed with SPSS software (version 16.0.1). Those patients, whose tumor had invaded the superior mesenteric artery, had extensive portal vein involvement or distant metastasis was considered as unresectable. The first Whipple procedure was recorded in our hospital in 2008. From 2008 till 20 March 2014, 70 cases were collected and analyzed. The mean age of cases was 58.4 years, the mean hospital stay length was 12.9 days (±6.23 days), mean operation time was 376 min (±37.3 min),. The most common presenting symptom was jaundice (78.6 %). Delayed gastric emptying was the most common post-operative complication. The most prevalent cause of reoperation was intra-abdominal abscess. Major morbidities of these patients consisted of cardiac arrhythmias (21.4%) and pneumonia (10%). Minor complications were wound infection (17.1%) and delayed gastric emptying (32.9%). The statistics revealed pancreatic anastomosis failure as 2.9% and a decrease in mortality rate from 50% during the first years of this study to 16% to 20% during the last years. In this case series, the time of operation decreased during the recent years .Analysis shows a correlation between operation time and pack cell transfused during the operation, but no correlation was found between operation time and post-operation hospitalization course. It is true that hospital setting, socioeconomic level of the patients including their compliance, and the expertise of the surgeons and surgical staff can have an influence on the result of this operation, but it seems that the magnitude of the surgical stress of this procedure and the (compromised) functional reserve of this patient population can be a notable factor influencing the outcome.

Evaluation of left ventricular scar identification from contrast enhanced magnetic resonance imaging for guidance of ventricular catheter ablation therapy

NASA Astrophysics Data System (ADS)

Rettmann, M. E.; Lehmann, H. I.; Johnson, S. B.; Packer, D. L.

2016-03-01

Patients with ventricular arrhythmias typically exhibit myocardial scarring, which is believed to be an important anatomic substrate for reentrant circuits, thereby making these regions a key target in catheter ablation therapy. In ablation therapy, a catheter is guided into the left ventricle and radiofrequency energy is delivered into the tissue to interrupt arrhythmic electrical pathways. Low bipolar voltage regions are typically localized during the procedure through point-by-point construction of an electroanatomic map by sampling the endocardial surface with the ablation catheter and are used as a surrogate for myocardial scar. This process is time consuming, requires significant skill, and has the potential to miss low voltage sites. This has led to efforts to quantify myocardial scar preoperatively using delayed, contrast-enhanced MRI. In this paper, we evaluate the utility of left ventricular scar identification from delayed contrast enhanced magnetic resonance imaging for guidance of catheter ablation of ventricular arrhythmias. Myocardial infarcts were created in three canines followed by a delayed, contrast enhanced MRI scan and electroanatomic mapping. The left ventricle and myocardial scar is segmented from preoperative MRI images and sampled points from the procedural electroanatomical map are registered to the segmented endocardial surface. Sampled points with low bipolar voltage points visually align with the segmented scar regions. This work demonstrates the potential utility of using preoperative delayed, enhanced MRI to identify myocardial scarring for guidance of ventricular catheter ablation therapy.

Cerebrospinal fluid enhancement on fluid attenuated inversion recovery images after carotid artery stenting with neuroprotective balloon occlusions: hemodynamic instability and blood-brain barrier disruption.

PubMed

Ogami, Ryo; Nakahara, Toshinori; Hamasaki, Osamu; Araki, Hayato; Kurisu, Kaoru

2011-10-01

A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined. CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

Timing in a Variable Interval Procedure: Evidence for a Memory Singularity

PubMed Central

Matell, Matthew S.; Kim, Jung S.; Hartshorne, Loryn

2013-01-01

Rats were trained in either a 30s peak-interval procedure, or a 15–45s variable interval peak procedure with a uniform distribution (Exp 1) or a ramping probability distribution (Exp 2). Rats in all groups showed peak shaped response functions centered around 30s, with the uniform group having an earlier and broader peak response function and rats in the ramping group having a later peak function as compared to the single duration group. The changes in these mean functions, as well as the statistics from single trial analyses, can be better captured by a model of timing in which memory is represented by a single, average, delay to reinforcement compared to one in which all durations are stored as a distribution, such as the complete memory model of Scalar Expectancy Theory or a simple associative model. PMID:24012783

1.0 T open-configuration magnetic resonance-guided microwave ablation of pig livers in real time

PubMed Central

Dong, Jun; Zhang, Liang; Li, Wang; Mao, Siyue; Wang, Yiqi; Wang, Deling; Shen, Lujun; Dong, Annan; Wu, Peihong

2015-01-01

The current fastest frame rate of each single image slice in MR-guided ablation is 1.3 seconds, which means delayed imaging for human at an average reaction time: 0.33 seconds. The delayed imaging greatly limits the accuracy of puncture and ablation, and results in puncture injury or incomplete ablation. To overcome delayed imaging and obtain real-time imaging, the study was performed using a 1.0-T whole-body open configuration MR scanner in the livers of 10 Wuzhishan pigs. A respiratory-triggered liver matrix array was explored to guide and monitor microwave ablation in real-time. We successfully performed the entire ablation procedure under MR real-time guidance at 0.202 s, the fastest frame rate for each single image slice. The puncture time ranged from 23 min to 3 min. For the pigs, the mean puncture time was shorted to 4.75 minutes and the mean ablation time was 11.25 minutes at power 70 W. The mean length and widths were 4.62 ± 0.24 cm and 2.64 ± 0.13 cm, respectively. No complications or ablation related deaths during or after ablation were observed. In the current study, MR is able to guide microwave ablation like ultrasound in real-time guidance showing great potential for the treatment of liver tumors. PMID:26315365

Relationship between mechanical dyssynchrony and intra-operative electrical delay times in patients undergoing cardiac resynchronization therapy

PubMed Central

2014-01-01

Background It is important to understand the relationship between electrical and mechanical ventricular activation in CRT patients. By measuring local electrical activation at multiple locations within the coronary veins and myocardial contraction at the same locations in the left ventricle, we determined the relationship between electrical and mechanical activation at potential left ventricular pacing locations. Methods In this study, mechanical contraction times were computed using high temporal resolution cine cardiovascular magnetic resonance (CMR) data, while electrical activation times were derived from intra-procedural local electrograms. Results In our cohort, there was a strong correlation between electrical and mechanical delay times within each patient (R2 = 0.78 ± 0.23). Additionally, the latest electrically activated location corresponded with the latest mechanically contracting location in 91% of patients. Conclusions This study provides initial evidence that our method of obtaining non-invasive mechanical activation patterns accurately reflects the underlying electromechanical substrate of intraventricular dyssynchrony. PMID:24393383

IRB Process Improvements: A Machine Learning Analysis.

PubMed

Shoenbill, Kimberly; Song, Yiqiang; Cobb, Nichelle L; Drezner, Marc K; Mendonca, Eneida A

2017-06-01

Clinical research involving humans is critically important, but it is a lengthy and expensive process. Most studies require institutional review board (IRB) approval. Our objective is to identify predictors of delays or accelerations in the IRB review process and apply this knowledge to inform process change in an effort to improve IRB efficiency, transparency, consistency and communication. We analyzed timelines of protocol submissions to determine protocol or IRB characteristics associated with different processing times. Our evaluation included single variable analysis to identify significant predictors of IRB processing time and machine learning methods to predict processing times through the IRB review system. Based on initial identified predictors, changes to IRB workflow and staffing procedures were instituted and we repeated our analysis. Our analysis identified several predictors of delays in the IRB review process including type of IRB review to be conducted, whether a protocol falls under Veteran's Administration purview and specific staff in charge of a protocol's review. We have identified several predictors of delays in IRB protocol review processing times using statistical and machine learning methods. Application of this knowledge to process improvement efforts in two IRBs has led to increased efficiency in protocol review. The workflow and system enhancements that are being made support our four-part goal of improving IRB efficiency, consistency, transparency, and communication.

Recreating the scene: an effective way to provide delayed punishment for inappropriate motor behavior.

PubMed Central

Van Houten, R; Rolider, A

1988-01-01

A mediated punishment procedure that involved recreating a behavioral sequence by guiding the subject through the behavior in the situation in which it occurred was used to suppress several severe problem behaviors in two developmentally delayed children. The mediational procedure was first used with a 4-year-old autistic boy for biting and then for foot stomping. Next the procedure was used for stealing and hoarding behavior with a multiply handicapped 17-year-old girl. Results indicated that the procedure was effective and produced relatively rapid results. One advantage of the procedure is that it provides an opportunity for trained personnel to apply restrictive procedures to low frequency behavior that occurs in their absence rather than relying on less qualified staff to implement the procedure immediately after the behavior occurs. PMID:2458333

Recreating the scene: an effective way to provide delayed punishment for inappropriate motor behavior.

PubMed

Van Houten, R; Rolider, A

1988-01-01

A mediated punishment procedure that involved recreating a behavioral sequence by guiding the subject through the behavior in the situation in which it occurred was used to suppress several severe problem behaviors in two developmentally delayed children. The mediational procedure was first used with a 4-year-old autistic boy for biting and then for foot stomping. Next the procedure was used for stealing and hoarding behavior with a multiply handicapped 17-year-old girl. Results indicated that the procedure was effective and produced relatively rapid results. One advantage of the procedure is that it provides an opportunity for trained personnel to apply restrictive procedures to low frequency behavior that occurs in their absence rather than relying on less qualified staff to implement the procedure immediately after the behavior occurs.

Isolating behavioral mechanisms of intertemporal choice: nicotine effects on delay discounting and amount sensitivity.

PubMed

Locey, Matthew L; Dallery, Jesse

2009-03-01

Many drugs of abuse produce changes in impulsive choice, that is, choice for a smaller-sooner reinforcer over a larger-later reinforcer. Because the alternatives differ in both delay and amount, it is not clear whether these drug effects are due to the differences in reinforcer delay or amount. To isolate the effects of delay, we used a titrating delay procedure. In phase 1, 9 rats made discrete choices between variable delays (1 or 19 s, equal probability of each) and a delay to a single food pellet. The computer titrated the delay to a single food pellet until the rats were indifferent between the two options. This indifference delay was used as the starting value for the titrating delay for all future sessions. We next evaluated the acute effects of nicotine (subcutaneous 1.0, 0.3, 0.1, and 0.03 mg/kg) on choice. If nicotine increases delay discounting, it should have increased preference for the variable delay. Instead, nicotine had very little effect on choice. In a second phase, the titrated delay alternative produced three food pellets instead of one, which was again produced by the variable delay (1 s or 19 s) alternative. Under this procedure, nicotine increased preference for the one pellet alternative. Nicotine-induced changes in impulsive choice are therefore likely due to differences in reinforcer amount rather than differences in reinforcer delay. In addition, it may be necessary to include an amount sensitivity parameter in any mathematical model of choice when the alternatives differ in reinforcer amount.

An analog scrambler for speech based on sequential permutations in time and frequency

NASA Astrophysics Data System (ADS)

Cox, R. V.; Jayant, N. S.; McDermott, B. J.

Permutation of speech segments is an operation that is frequently used in the design of scramblers for analog speech privacy. In this paper, a sequential procedure for segment permutation is considered. This procedure can be extended to two dimensional permutation of time segments and frequency bands. By subjective testing it is shown that this combination gives a residual intelligibility for spoken digits of 20 percent with a delay of 256 ms. (A lower bound for this test would be 10 percent). The complexity of implementing such a system is considered and the issues of synchronization and channel equalization are addressed. The computer simulation results for the system using both real and simulated channels are examined.

The N-policy for an unreliable server with delaying repair and two phases of service

NASA Astrophysics Data System (ADS)

Choudhury, Gautam; Ke, Jau-Chuan; Tadj, Lotfi

2009-09-01

This paper deals with an MX/G/1 with an additional second phase of optional service and unreliable server, which consist of a breakdown period and a delay period under N-policy. While the server is working with any phase of service, it may break down at any instant and the service channel will fail for a short interval of time. Further concept of the delay time is also introduced. If no customer arrives during the breakdown period, the server becomes idle in the system until the queue size builds up to a threshold value . As soon as the queue size becomes at least N, the server immediately begins to serve the first phase of regular service to all the waiting customers. After the completion of which, only some of them receive the second phase of the optional service. We derive the queue size distribution at a random epoch and departure epoch as well as various system performance measures. Finally we derive a simple procedure to obtain optimal stationary policy under a suitable linear cost structure.

Aging of the field-induced asymmetry in a disordered ferroelectric

NASA Astrophysics Data System (ADS)

Bonello, B.; Doussineau, P.; Dupuis, V.; Levelut, A.

2006-07-01

The isothermal aging of the asymmetry induced in the disordered dielectric crystal KTa_{1-x} Nbx O3 (x=0.027) submitted to the biasing electric field E, is investigated. To this end, the response of the complex dielectric constant to infinitesimal field changes δ{E}, applied to the sample after a variable aging delay, has been measured for different magnitudes of E and after different aging delays. Two different experimental procedures have been used: in both cases the response strongly depends on the time spent under field. For short aging delays, the response has a strong contribution proportional to δE and a weak quadratic contribution proportional to left({δ E}right)^2. As time elapses, the linear and the quadratic contributions age in opposite ways: the former decreases whereas the latter increases. This paradoxical behaviour is analyzed in the framework of a model which attributes aging and the related effects (rejuvenation, memory) to the evolution of polarization domain walls: the decrease of the linear contribution is related to the decrease of the total wall area, while the increase of the quadratic term is attributed to wall reconformations.

Equivalent Stimuli Are More Strongly Related after Training with Delayed Matching than after Simultaneous Matching: A Study Using the Implicit Relational Assessment Procedure (IRAP)

ERIC Educational Resources Information Center

Bortoloti, Renato; de Rose, Julio C.

2012-01-01

Bortoloti and de Rose (2009) found evidence that the level of functional transfer is higher in equivalence classes generated by delayed matching to sample (DMTS) than in classes generated by simultaneous matching (SMTS). We attempted to replicate these findings with the Implicit Relational Assessment Procedure (IRAP). Two experimental groups…

Factors affecting professional delay in diagnosis and treatment of oral cancer in Iran.

PubMed

Esmaelbeigi, Farhad; Hadji, Maryam; Harirchi, Iraj; Omranipour, Ramesh; vand Rajabpour, Mojtaba; Zendehdel, Kazem

2014-04-01

Oral cancer is the most common malignant tumor among head and neck cancers. Delay in diagnosis affects the treatment and prognosis of oral cancer. We measured the professional delay in the diagnosis and its attributes in the Cancer Institute of Iran, the largest referral center for oral cancer patients in the country.  We interviewed oral cancer patients to measure the delay and used case-control approach to study association of various prognostic factors with professional delay and tumor stage. Out of 206 patients, 71.4% were diagnosed at the advanced stage. The median of the patient, professional and total delays were 45, 86 and 140 day, receptively. In the univariate model, prescription of medicines like analgesics (OR = 5.3, 95% CI 2.2-12.9) and history of dental procedure (OR=6.8, 95% CI 1.7-26.9) were associated with higher risk of delay compared to patient who were biopsied from the beginning. History of loose teeth increased risk of delay 4 times (OR = 4.0, 95% CI 1.6-9.8). Patients with primary education had 70% lower risk of delay compared to the illiterate patients (OR = 0.3, 95% CI 0.1-0.7) and the risk was lower among patients who had diploma (OR = 0.04, 95% CI 0-0.7) and college education (OR = 0.1, 95% CI 0-0.4). The delayed patients were diagnosed in more advanced stage compared to the patients without delay (OR = 2.1, 95% CI 1.0-4.4). Development of a national guideline for follow-up of oral lesions, training and awareness of health care professionals about oral cancer diagnosis may decrease the delay and improve the oral cancer outcome in Iran.

Design and evaluation of Continuous Descent Approach as a fuel-saving procedure

NASA Astrophysics Data System (ADS)

Jin, Li

Continuous Descent Approach (CDA), which is among the key concepts of the Next Generation Air Transportation System (NextGen), is a fuel economical procedure, but requires increased separation to accommodate spacing uncertainties among arriving aircraft. Such negative impact is often overlooked when benefits are estimated. Although a considerable number of researches have been devoted to the estimation of potential fuel saving of CDA, few have attempted to explain the fuel saving observed in field tests from an analytical point of view. This research gives insights into the reasons why CDA saves fuel, and a number of design guidelines for CDA procedures are derived. The analytical relationship between speed, altitude, and time-cumulative fuel consumption is derived based on Base of Aircraft Data (BADA) Total Energy Model. Theoretical analysis implies that speed profile has an impact as substantial as, if not more than, vertical profile on the fuel consumption in the terminal area. In addition, CDA is not intrinsically a fuel-saving procedure: whether CDA saves fuel or not is contingent upon whether the speed profile is properly designed or not. Based on this model, the potential fuel savings due to CDA at San Francisco International Airport were estimated, and the accuracy of this estimation is analyzed. Possible uncertainties in this fuel estimation primarily resulted from the modeled CDA procedure and the inaccuracy of BADA. This thesis also investigates the fuel savings due to CDAs under high traffic conditions, counting not only the savings benefiting from optimal vertical profiles but also the extra fuel burn resulting from the increased separations. The simulated CDAs traffic is based on radar track data, and deconflicted by a scheduling algorithm that targets minimized delays. The delays are absorbed by speed change and path stretching, accounting for the air traffic controls that are entailed by CDAs. The fuel burn statistics calculated based on the BADA Total Energy Model reveals that the CDAs save on average 171.87 kg per arrival, but the number is discounted by delay absorption. The savings diminish as the arrival demand increases, and could be even negative due to large delays. The throughput analysis demonstrated that the impact of CDA on airport capacity is insignificant and tolerable. The Atlanta International Airport was used as the testbed for sensitivity analysis, and the New York Metroplex was used as the test bed for throughput analysis.

Hyperglycaemia and ketosis in a non-diabetic patient--an unusual cause of delayed recovery.

PubMed

Pawar, Sundeep T; Nath, Soumya S; Ansari, Farrukh

2014-01-01

We report a case of hyperglycaemia and ketosis developing in a non-diabetic patient who underwent a neurosurgical procedure under general anaesthesia. A 52-year-old non-diabetic female patient underwent excision of acoustic neuroma under general anaesthesia. Pancreatic function was not disturbed and she received a single dose of dexamethasone (8 mg) and paracetamol (1 g). Delayed recovery from anaesthesia occurred. On investigation, she was found to have hyperglycaemia and ketosis. She was further managed on the line of diabetic ketoacidosis. After 24 hours, when blood glucose had normalised and ketosis abated, she could be weaned from mechanical ventilation and extubated. The patient did not receive any drugs known to cause such a condition. To the best of our knowledge, hyperglycaemia and ketosis developing in a non-diabetic patient causing delayed recovery and extubation is here reported for the first time.

The timing of umbilical cord clamping at birth: physiological considerations.

PubMed

Hooper, Stuart B; Binder-Heschl, Corinna; Polglase, Graeme R; Gill, Andrew W; Kluckow, Martin; Wallace, Euan M; Blank, Douglas; Te Pas, Arjan B

2016-01-01

While it is now recognized that umbilical cord clamping (UCC) at birth is not necessarily an innocuous act, there is still much confusion concerning the potential benefits and harms of this common procedure. It is most commonly assumed that delaying UCC will automatically result in a time-dependent net placental-to-infant blood transfusion, irrespective of the infant's physiological state. Whether or not this occurs, will likely depend on the infant's physiological state and not on the amount of time that has elapsed between birth and umbilical cord clamping (UCC). However, we believe that this is an overly simplistic view of what can occur during delayed UCC and ignores the benefits associated with maintaining the infant's venous return and cardiac output during transition. Recent experimental evidence and observations in humans have provided compelling evidence to demonstrate that time is not a major factor influencing placental-to-infant blood transfusion after birth. Indeed, there are many factors that influence blood flow in the umbilical vessels after birth, which depending on the dominating factors could potentially result in infant-to-placental blood transfusion. The most dominant factors that influence umbilical artery and venous blood flows after birth are lung aeration, spontaneous inspirations, crying and uterine contractions. It is still not entirely clear whether gravity differentially alters umbilical artery and venous flows, although the available data suggests that its influence, if present, is minimal. While there is much support for delaying UCC at birth, much of the debate has focused on a time-based approach, which we believe is misguided. While a time-based approach is much easier and convenient for the caregiver, ignoring the infant's physiology during delayed UCC can potentially be counter-productive for the infant.

Near real-time adverse drug reaction surveillance within population-based health networks: methodology considerations for data accrual.

PubMed

Avery, Taliser R; Kulldorff, Martin; Vilk, Yury; Li, Lingling; Cheetham, T Craig; Dublin, Sascha; Davis, Robert L; Liu, Liyan; Herrinton, Lisa; Brown, Jeffrey S

2013-05-01

This study describes practical considerations for implementation of near real-time medical product safety surveillance in a distributed health data network. We conducted pilot active safety surveillance comparing generic divalproex sodium to historical branded product at four health plans from April to October 2009. Outcomes reported are all-cause emergency room visits and fractures. One retrospective data extract was completed (January 2002-June 2008), followed by seven prospective monthly extracts (January 2008-November 2009). To evaluate delays in claims processing, we used three analytic approaches: near real-time sequential analysis, sequential analysis with 1.5 month delay, and nonsequential (using final retrospective data). Sequential analyses used the maximized sequential probability ratio test. Procedural and logistical barriers to active surveillance were documented. We identified 6586 new users of generic divalproex sodium and 43,960 new users of the branded product. Quality control methods identified 16 extract errors, which were corrected. Near real-time extracts captured 87.5% of emergency room visits and 50.0% of fractures, which improved to 98.3% and 68.7% respectively with 1.5 month delay. We did not identify signals for either outcome regardless of extract timeframe, and slight differences in the test statistic and relative risk estimates were found. Near real-time sequential safety surveillance is feasible, but several barriers warrant attention. Data quality review of each data extract was necessary. Although signal detection was not affected by delay in analysis, when using a historical control group differential accrual between exposure and outcomes may theoretically bias near real-time risk estimates towards the null, causing failure to detect a signal. Copyright © 2013 John Wiley & Sons, Ltd.

Rapid Access Real-Time device and Rapid Access software: new tools in the armamentarium of capsule endoscopy.

PubMed

Spada, Cristiano; Riccioni, Maria Elena; Costamagna, Guido

2007-07-01

Small bowel capsule endoscopy represents a significant advance in the investigation of the small bowel, allowing direct visualization of this section of the gastrointestinal system. More recently, new video capsules have been released, specifically designed to investigate the esophagus and the colon. In June 2006, Given Imaging Ltd received marketing clearance from the US FDA for the Rapid Access Real-Time (RT) and Rapid Access software. The Rapid Access RT is a handheld device that enables real-time viewing during capsule endoscopy procedures. To date, the clinical benefits of this device are unknown as studies on the Rapid Access RT system have not yet been published. However, it appears that the Rapid Access RT system may reduce the examination and reading time, and may impact significantly in cases where it is important to know the precise localization of the capsule (during PillCam ESO ingestion procedures, PillCam Colon examinations or when delayed gastric transit is suspected) or in case of severe gastrointestinal bleeding (when a therapeutic procedure is required urgently).

Obtaining reliable phase-gradient delays from otoacoustic emission data.

PubMed

Shera, Christopher A; Bergevin, Christopher

2012-08-01

Reflection-source otoacoustic emission phase-gradient delays are widely used to obtain noninvasive estimates of cochlear function and properties, such as the sharpness of mechanical tuning and its variation along the length of the cochlear partition. Although different data-processing strategies are known to yield different delay estimates and trends, their relative reliability has not been established. This paper uses in silico experiments to evaluate six methods for extracting delay trends from reflection-source otoacoustic emissions (OAEs). The six methods include both previously published procedures (e.g., phase smoothing, energy-weighting, data exclusion based on signal-to-noise ratio) and novel strategies (e.g., peak-picking, all-pass factorization). Although some of the methods perform well (e.g., peak-picking), others introduce substantial bias (e.g., phase smoothing) and are not recommended. In addition, since standing waves caused by multiple internal reflection can complicate the interpretation and compromise the application of OAE delays, this paper develops and evaluates two promising signal-processing strategies, the first based on time-frequency filtering using the continuous wavelet transform and the second on cepstral analysis, for separating the direct emission from its subsequent reflections. Altogether, the results help to resolve previous disagreements about the frequency dependence of human OAE delays and the sharpness of cochlear tuning while providing useful analysis methods for future studies.

The ecological rationality of delay tolerance: insights from capuchin monkeys.

PubMed

Addessi, Elsa; Paglieri, Fabio; Focaroli, Valentina

2011-04-01

Both human and non-human animals often face decisions between options available at different times, and the capacity of delaying gratification has usually been considered one of the features distinguishing humans from other animals. However, this characteristic can widely vary across individuals, species, and types of task and it is still unclear whether it is accounted for by phylogenetic relatedness, feeding ecology, social structure, or metabolic rate. To disentangle these hypotheses, we evaluated temporal preferences in capuchin monkeys, South-American primates that, despite splitting off from human lineage approximately 35 million years ago, show striking behavioural analogies with the great apes. Then, we compared capuchins' performance with that of the other primate species tested so far with the same procedure. Overall, capuchins showed a delay tolerance significantly higher than closely related species, such as marmosets and tamarins, and comparable to that shown by great apes. Capuchins' tool use abilities might explain their comparatively high preference for delayed options in inter-temporal choices. Moreover, as in humans, capuchin females showed a greater delay tolerance than males, possibly because of their less opportunistic foraging style. Thus, our results shed light on the evolutionary origins of self-control supporting explanations of delay tolerance in terms of feeding ecology. Copyright © 2010 Elsevier B.V. All rights reserved.

Remifentanil maintains lower initial delayed nonmatching-to-sample accuracy compared to food pellets in male rhesus monkeys.

PubMed

Hutsell, Blake A; Banks, Matthew L

2017-12-01

Emerging human laboratory and preclinical drug self-administration data suggest that a history of contingent abused drug exposure impairs performance in operant discrimination procedures, such as delayed nonmatching-to-sample (DNMTS), that are hypothesized to assess components of executive function. However, these preclinical discrimination studies have exclusively used food as the reinforcer and the effects of drugs as reinforcers in these operant procedures are unknown. The present study determined effects of contingent intravenous remifentanil injections on DNMTS performance hypothesized to assess 1 aspect of executive function, working memory. Daily behavioral sessions consisted of 2 components with sequential intravenous remifentanil (0, 0.01-1.0 μg/kg/injection) or food (0, 1-10 pellets) availability in nonopioid dependent male rhesus monkeys (n = 3). Remifentanil functioned as a reinforcer in the DNMTS procedure. Similar delay-dependent DNMTS accuracy was observed under both remifentanil- and food-maintained components, such that higher accuracies were maintained at shorter (0.1-1.0 s) delays and lower accuracies approaching chance performance were maintained at longer (10-32 s) delays. Remifentanil maintained significantly lower initial DNMTS accuracy compared to food. Reinforcer magnitude was not an important determinant of DNMTS accuracy for either remifentanil or food. These results extend the range of experimental procedures under which drugs function as reinforcers. Furthermore, the selective remifentanil-induced decrease in initial DNMTS accuracy is consistent with a selective impairment of attentional, but not memorial, processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Real-time estimation of ionospheric delay using GPS measurements

NASA Astrophysics Data System (ADS)

Lin, Lao-Sheng

1997-12-01

When radio waves such as the GPS signals propagate through the ionosphere, they experience an extra time delay. The ionospheric delay can be eliminated (to the first order) through a linear combination of L1 and L2 observations from dual-frequency GPS receivers. Taking advantage of this dispersive principle, one or more dual- frequency GPS receivers can be used to determine a model of the ionospheric delay across a region of interest and, if implemented in real-time, can support single-frequency GPS positioning and navigation applications. The research objectives of this thesis were: (1) to develop algorithms to obtain accurate absolute Total Electron Content (TEC) estimates from dual-frequency GPS observables, and (2) to develop an algorithm to improve the accuracy of real-time ionosphere modelling. In order to fulfil these objectives, four algorithms have been proposed in this thesis. A 'multi-day multipath template technique' is proposed to mitigate the pseudo-range multipath effects at static GPS reference stations. This technique is based on the assumption that the multipath disturbance at a static station will be constant if the physical environment remains unchanged from day to day. The multipath template, either single-day or multi-day, can be generated from the previous days' GPS data. A 'real-time failure detection and repair algorithm' is proposed to detect and repair the GPS carrier phase 'failures', such as the occurrence of cycle slips. The proposed algorithm uses two procedures: (1) application of a statistical test on the state difference estimated from robust and conventional Kalman filters in order to detect and identify the carrier phase failure, and (2) application of a Kalman filter algorithm to repair the 'identified carrier phase failure'. A 'L1/L2 differential delay estimation algorithm' is proposed to estimate GPS satellite transmitter and receiver L1/L2 differential delays. This algorithm, based on the single-site modelling technique, is able to estimate the sum of the satellite and receiver L1/L2 differential delay for each tracked GPS satellite. A 'UNSW grid-based algorithm' is proposed to improve the accuracy of real-time ionosphere modelling. The proposed algorithm is similar to the conventional grid-based algorithm. However, two modifications were made to the algorithm: (1) an 'exponential function' is adopted as the weighting function, and (2) the 'grid-based ionosphere model' estimated from the previous day is used to predict the ionospheric delay ratios between the grid point and reference points. (Abstract shortened by UMI.)

Determination of Nutrient Intakes by a Modified Visual Estimation Method and Computerized Nutritional Analysis for Dietary Assessments

DTIC Science & Technology

1987-09-01

a useful average for population studies, do not delay data processing , and is relatively Inexpensive. Using MVEN and observing recipe preparation...for population studies, do not delay data processing , and is relatively inexpensive. Using HVEM and observing recipe preparation procedures improve the...extensive review of the procedures and problems in design, collection, analysis, processing and interpretation of dietary survey data for individuals

Using Video Modeling with Voiceover Instruction Plus Feedback to Train Staff to Implement Direct Teaching Procedures.

PubMed

Giannakakos, Antonia R; Vladescu, Jason C; Kisamore, April N; Reeve, Sharon A

2016-06-01

Direct teaching procedures are often an important part of early intensive behavioral intervention for consumers with autism spectrum disorder. In the present study, a video model with voiceover (VMVO) instruction plus feedback was evaluated to train three staff trainees to implement a most-to-least direct (MTL) teaching procedure. Probes for generalization were conducted with untrained direct teaching procedures (i.e., least-to-most, prompt delay) and with an actual consumer. The results indicated that VMVO plus feedback was effective in training the staff trainees to implement the MTL procedure. Although additional feedback was required for the staff trainees to show mastery of the untrained direct teaching procedures (i.e., least-to-most and prompt delay) and with an actual consumer, moderate to high levels of generalization were observed.

The effect of the dynamic wet troposphere on VLBI measurements

NASA Technical Reports Server (NTRS)

Treuhaft, R. N.; Lanyi, G. E.

1986-01-01

Calculations using a statistical model of water vapor fluctuations yield the effect of the dynamic wet troposphere on Very Long Baseline Interferometry (VLBI) measurements. The statistical model arises from two primary assumptions: (1) the spatial structure of refractivity fluctuations can be closely approximated by elementary (Kolmogorov) turbulence theory, and (2) temporal fluctuations are caused by spatial patterns which are moved over a site by the wind. The consequences of these assumptions are outlined for the VLBI delay and delay rate observables. For example, wet troposphere induced rms delays for Deep Space Network (DSN) VLBI at 20-deg elevation are about 3 cm of delay per observation, which is smaller, on the average, than other known error sources in the current DSN VLBI data set. At 20-deg elevation for 200-s time intervals, water vapor induces approximately 1.5 x 10 to the minus 13th power s/s in the Allan standard deviation of interferometric delay, which is a measure of the delay rate observable error. In contrast to the delay error, the delay rate measurement error is dominated by water vapor fluctuations. Water vapor induced VLBI parameter errors and correlations are calculated. For the DSN, baseline length parameter errors due to water vapor fluctuations are in the range of 3 to 5 cm. The above physical assumptions also lead to a method for including the water vapor fluctuations in the parameter estimation procedure, which is used to extract baseline and source information from the VLBI observables.

Diagnosis of delay-deadline failures in real time discrete event models.

PubMed

Biswas, Santosh; Sarkar, Dipankar; Bhowal, Prodip; Mukhopadhyay, Siddhartha

2007-10-01

In this paper a method for fault detection and diagnosis (FDD) of real time systems has been developed. A modeling framework termed as real time discrete event system (RTDES) model is presented and a mechanism for FDD of the same has been developed. The use of RTDES framework for FDD is an extension of the works reported in the discrete event system (DES) literature, which are based on finite state machines (FSM). FDD of RTDES models are suited for real time systems because of their capability of representing timing faults leading to failures in terms of erroneous delays and deadlines, which FSM-based ones cannot address. The concept of measurement restriction of variables is introduced for RTDES and the consequent equivalence of states and indistinguishability of transitions have been characterized. Faults are modeled in terms of an unmeasurable condition variable in the state map. Diagnosability is defined and the procedure of constructing a diagnoser is provided. A checkable property of the diagnoser is shown to be a necessary and sufficient condition for diagnosability. The methodology is illustrated with an example of a hydraulic cylinder.

Laparoscopic Whipple procedure: review of the literature.

PubMed

Gagner, Michel; Palermo, Mariano

2009-01-01

Laparoscopic pancreatic surgery represents one of the most advanced applications for laparoscopic surgery currently in use. In the past, minimally invasive techniques were only used for diagnostic laparoscopy, staging of pancreatic cancer, and palliative procedures for unresectable pancreatic cancer. With new advances in technology and instrumentation, some sophisticated procedures are currently available, such as the Whipple procedure, one of the most sophisticated applications of minimally invasive surgery. A review of the literature shows that 146 laparoscopic Whipple procedures have been published worldwide since 1994. The authors analyzed blood loss, mean operating time, hospital stay, conversion rate, mean age, mortality rate, lymph nodes in the pathologic findings, follow up, and complications. Mean age was 59.1 years; mean operating time was 439 min. The average blood loss for the reviewed literature was 143 mL; median hospital stay was 18 days; conversion rate was 46%; number of lymph nodes in the pathologic findings was 19; and mortalities related to the procedure was low, 2 patients (1.3%) and the complication rate was 16% (23/46 patients). Complications included 2 hemorrhages, 4 bowel obstructions, 1 stress ulcer, 1 delay of gastric emptying, 4 pneumonias, and 11 leaks. This review demonstrates that the laparoscopic Whipple procedure is not only feasible but also safe, with low mortality and acceptable rates of complications.

34 CFR 303.420 - Due process procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... infant's or toddler's development is so rapid that undue delay could be potentially harmful. [58 FR 40959... AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND... Children § 303.420 Due process procedures. Each system must include written procedures including procedures...

34 CFR 303.420 - Due process procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... infant's or toddler's development is so rapid that undue delay could be potentially harmful. [58 FR 40959... AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND... Children § 303.420 Due process procedures. Each system must include written procedures including procedures...

Procedural learning is impaired in dyslexia: Evidence from a meta-analysis of serial reaction time studies☆

PubMed Central

Lum, Jarrad A.G.; Ullman, Michael T.; Conti-Ramsden, Gina

2013-01-01

A number of studies have investigated procedural learning in dyslexia using serial reaction time (SRT) tasks. Overall, the results have been mixed, with evidence of both impaired and intact learning reported. We undertook a systematic search of studies that examined procedural learning using SRT tasks, and synthesized the data using meta-analysis. A total of 14 studies were identified, representing data from 314 individuals with dyslexia and 317 typically developing control participants. The results indicate that, on average, individuals with dyslexia have worse procedural learning abilities than controls, as indexed by sequence learning on the SRT task. The average weighted standardized mean difference (the effect size) was found to be 0.449 (CI95: .204, .693), and was significant (p < .001). However, moderate levels of heterogeneity were found between study-level effect sizes. Meta-regression analyses indicated that studies with older participants that used SRT tasks with second order conditional sequences, or with older participants that used sequences that were presented a large number of times, were associated with smaller effect sizes. These associations are discussed with respect to compensatory and delayed memory systems in dyslexia. PMID:23920029

One process is not enough! A speed-accuracy tradeoff study of recognition memory.

PubMed

Boldini, Angela; Russo, Riccardo; Avons, S E

2004-04-01

Speed-accuracy tradeoff (SAT) methods have been used to contrast single- and dual-process accounts of recognition memory. In these procedures, subjects are presented with individual test items and are required to make recognition decisions under various time constraints. In this experiment, we presented word lists under incidental learning conditions, varying the modality of presentation and level of processing. At test, we manipulated the interval between each visually presented test item and a response signal, thus controlling the amount of time available to retrieve target information. Study-test modality match had a beneficial effect on recognition accuracy at short response-signal delays (< or =300 msec). Conversely, recognition accuracy benefited more from deep than from shallow processing at study only at relatively long response-signal delays (> or =300 msec). The results are congruent with views suggesting that both fast familiarity and slower recollection processes contribute to recognition memory.

Suppression of phase synchronisation in network based on cat's brain.

PubMed

Lameu, Ewandson L; Borges, Fernando S; Borges, Rafael R; Iarosz, Kelly C; Caldas, Iberê L; Batista, Antonio M; Viana, Ricardo L; Kurths, Jürgen

2016-04-01

We have studied the effects of perturbations on the cat's cerebral cortex. According to the literature, this cortex structure can be described by a clustered network. This way, we construct a clustered network with the same number of areas as in the cat matrix, where each area is described as a sub-network with a small-world property. We focus on the suppression of neuronal phase synchronisation considering different kinds of perturbations. Among the various controlling interventions, we choose three methods: delayed feedback control, external time-periodic driving, and activation of selected neurons. We simulate these interventions to provide a procedure to suppress undesired and pathological abnormal rhythms that can be associated with many forms of synchronisation. In our simulations, we have verified that the efficiency of synchronisation suppression by delayed feedback control is higher than external time-periodic driving and activation of selected neurons of the cat's cerebral cortex with the same coupling strengths.

Chaos synchronization of uncertain chaotic systems using composite nonlinear feedback based integral sliding mode control.

PubMed

Mobayen, Saleh

2018-06-01

This paper proposes a combination of composite nonlinear feedback and integral sliding mode techniques for fast and accurate chaos synchronization of uncertain chaotic systems with Lipschitz nonlinear functions, time-varying delays and disturbances. The composite nonlinear feedback method allows accurate following of the master chaotic system and the integral sliding mode control provides invariance property which rejects the perturbations and preserves the stability of the closed-loop system. Based on the Lyapunov- Krasovskii stability theory and linear matrix inequalities, a novel sufficient condition is offered for the chaos synchronization of uncertain chaotic systems. This method not only guarantees the robustness against perturbations and time-delays, but also eliminates reaching phase and avoids chattering problem. Simulation results demonstrate that the suggested procedure leads to a great control performance. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Patient and health service delay in pulmonary tuberculosis patients attending a referral hospital: a cross-sectional study.

PubMed

Kiwuwa, Mpungu S; Charles, Karamagi; Harriet, Mayanja Kizza

2005-11-24

Delays in diagnosis and initiation of effective treatment increase morbidity and mortality from tuberculosis as well as the risk of transmission in the community. The aim of this study was to determine the time taken for patients later confirmed as having TB to present with symptoms to the first health provider (patient delay) and the time taken between the first health care visit and initiation of tuberculosis treatment (health service delay). Factors relating to these 'delays' were analyzed. A cross-sectional survey, of 231 newly diagnosed smear-positive tuberculosis patients was conducted in Mulago National referral Hospital Kampala, from January to May 2002. Socio-demographic, lifestyle and health seeking factors were evaluated for their association with patient delay (> 2 weeks) and health service delay (> 4 weeks), using odds ratios with 95% confidence intervals (CI) including multivariate logistic regression. The median total delay to treatment initiation was 12 weeks. Patients often presented to drug shops or pharmacies (39.4%) and private clinics (36.8%) more commonly than government health units (14%) as initial contacts. Several independent predictors of 'patient delay' were identified: being hospitalized (odds ratio [0R] = 0.32; 95% CI: 0.12-0.80), daily alcohol consumption (OR = 3.7; CI: 1.57-9.76), subsistence farming (OR = 4.70; CI: 1.67-13.22), and perception of smoking as a cause of TB (OR = 5.54; CI: 2.26-13.58). Independent predictors of 'health service delay' were: > 2 health seeking encounters per month (OR = 2.74; CI: 1.10-6.83), and medical expenditure on TB related symptoms > 29 US dollars (OR = 3.88; CI: 1.19-12.62). Perceived TB stigma and education status was not associated with either form of delay. Delay in diagnosis of TB is prolonged at the referral centre with a significant proportion of Health service delay. More specific and effective health education of the general public on tuberculosis and seeking of appropriate medical consultation is likely to improve case detection. Certain specific groups require further attention. Alcoholics and subsistence farmers should be targeted to improve accessibility to TB treatment. Continuing medical education about TB management procedures for health providers and improvement in the capacity of TB control services should be undertaken.

Barriers and facilitators of surgical care in rural Uganda: a mixed methods study.

PubMed

Nwanna-Nzewunwa, Obieze C; Ajiko, Mary-Margaret; Kirya, Fred; Epodoi, Joseph; Kabagenyi, Fiona; Batibwe, Emmanuel; Feldhaus, Isabelle; Juillard, Catherine; Dicker, Rochelle

2016-07-01

Surgical care delivery is poorly understood in resource-limited settings. To effectively move toward universal health coverage, there is a critical need to understand surgical care delivery in developing countries. This study aims to identify the barriers and facilitators of surgical care delivery at Soroti Regional Referral Hospital in Uganda. In this mixed methods study, we (1) applied the Surgeons OverSeas' Personnel, Infrastructure, Procedures, Equipment, and Supplies tool to assess surgical capacity; (2) retrospectively reviewed inpatient records; (3) conducted four semistructured focus group discussions with 18 purposively sampled providers involved in perioperative care; and (4) observed the perioperative process of care using a time and motion approach. Descriptive statistics were generated from quantitative data. Qualitative data were thematically analyzed. The Personnel, Infrastructure, Procedures, Equipment, and Supplies survey revealed severe deficiencies in workforce (P-score = 14) and infrastructure (I-score = 5). Equipment, supplies, and procedures were generally available. Male and female wards were overbooked 83% and 60% of the time, respectively. Providers identified lack of space, patient overload, and superfluous patients' attendants as barriers to surgical care. Workforce challenges were tackled using teamwork and task sharing. Inadequate equipment and processes were addressed using improvisations. All observed subjects (n = 31) received interventions. The median decision-to-intervention time was 2.5 h (Interquartile Range [IQR], 0.4, 21.4). However, 48% of subjects experienced delays. Median decision-to-intervention delay was 14.8 h (IQR, 0.9, 26.6). Despite severe workforce and physical infrastructural deficiencies at Soroti Regional Referral Hospital, providers are adjusting and innovating to deliver surgical care. Copyright © 2016 Elsevier Inc. All rights reserved.

Emergency surgery pre-operative delays - realities and economic impacts.

PubMed

O'Leary, D P; Beecher, S; McLaughlin, R

2014-12-01

A key principle of acute surgical service provision is the establishment of a distinct patient flow process and an emergency theatre. Time-to-theatre (TTT) is a key performance indicator of theatre efficiency. The combined impacts of an aging population, increasing demands and complexity associated with centralisation of emergency and oncology services has placed pressure on emergency theatre access. We examined our institution's experience with running a designated emergency theatre for acute surgical patients. A retrospective review of an electronic prospectively maintained database was performed between 1/1/12 and 31/12/13. A cost analysis was conducted to assess the economic impact of delayed TTT, with every 24hr delay incurring the cost of an additional overnight bed. Delays and the economic effects were assessed only after the first 24 h as an in-patient had elapsed. In total, 7041 procedures were performed. Overall mean TTT was 26 h, 2 min. There were significant differences between different age groups, with those aged under 16 year and over 65 having mean TTT at 6 h, 34 min (95% C.I. 0.51-2.15, p < 0.001) and 23 h, 41 min (95% C.I. 19.6-23.9, p < 0.001) respectively. 2421 (34%) waited greater than 24 h for emergency procedures. The >65 years age group had a mean TTT of 23 h, 41 min which was significantly longer than the overall mean TTT Vascular and urological emergencies are significantly disadvantaged in competition with other services for a shared emergency theatre. The economic impact of delayed TTT was calculated at €7,116,000, or €9880/day of additional costs generated from delayed TTT over a 24 month period. One third of patients waited longer than 24 h for emergency surgery, with the elderly disproportionately represented in this group. Aside from the clinical risks of delayed and out of hours surgery, such practices incur significant additional costs. New strategies must be devised to ensure efficient access to emergency theatres, investment in such services is likely to be financially and clinically beneficial. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption

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

Ogami, Ryo, E-mail: ogami.r@mazda.co.jp; Nakahara, Toshinori; Hamasaki, Osamu

2011-10-15

Purpose: A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Methods: Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors weremore » examined. Results: CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Conclusions: Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.« less

Design of a two-level power system linear state estimator

NASA Astrophysics Data System (ADS)

Yang, Tao

The availability of synchro-phasor data has raised the possibility of a linear state estimator if the inputs are only complex currents and voltages and if there are enough such measurements to meet observability and redundancy requirements. Moreover, the new digital substations can perform some of the computation at the substation itself resulting in a more accurate two-level state estimator. The objective of this research is to develop a two-level linear state estimator processing synchro-phasor data and estimating the states at both the substation level and the control center level. Both the mathematical algorithms that are different from those in the present state estimation procedure and the layered architecture of databases, communications and application programs that are required to support this two-level linear state estimator are described in this dissertation. Besides, as the availability of phasor measurements at substations will increase gradually, this research also describes how the state estimator can be enhanced to handle both the traditional state estimator and the proposed linear state estimator simultaneously. This provides a way to immediately utilize the benefits in those parts of the system where such phasor measurements become available and provides a pathway to transition to the smart grid of the future. The design procedure of the two-level state estimator is applied to two study systems. The first study system is the IEEE-14 bus system. The second one is the 179 bus Western Electricity Coordinating Council (WECC) system. The static database for the substations is constructed from the power flow data of these systems and the real-time measurement database is produced by a power system dynamic simulating tool (TSAT). Time-skew problems that may be caused by communication delays are also considered and simulated. We used the Network Simulator (NS) tool to simulate a simple communication system and analyse its time delay performance. These time delays were too small to affect the results especially since the measurement data is time-stamped and the state estimator for these small systems could be run with subseconf frequency. Keywords: State Estimation, Synchro-Phasor Measurement, Distributed System, Energy Control Center, Substation, Time-skew

Optimal Signal Processing of Frequency-Stepped CW Radar Data

NASA Technical Reports Server (NTRS)

Ybarra, Gary A.; Wu, Shawkang M.; Bilbro, Griff L.; Ardalan, Sasan H.; Hearn, Chase P.; Neece, Robert T.

1995-01-01

An optimal signal processing algorithm is derived for estimating the time delay and amplitude of each scatterer reflection using a frequency-stepped CW system. The channel is assumed to be composed of abrupt changes in the reflection coefficient profile. The optimization technique is intended to maximize the target range resolution achievable from any set of frequency-stepped CW radar measurements made in such an environment. The algorithm is composed of an iterative two-step procedure. First, the amplitudes of the echoes are optimized by solving an overdetermined least squares set of equations. Then, a nonlinear objective function is scanned in an organized fashion to find its global minimum. The result is a set of echo strengths and time delay estimates. Although this paper addresses the specific problem of resolving the time delay between the first two echoes, the derivation is general in the number of echoes. Performance of the optimization approach is illustrated using measured data obtained from an HP-X510 network analyzer. It is demonstrated that the optimization approach offers a significant resolution enhancement over the standard processing approach that employs an IFFT. Degradation in the performance of the algorithm due to suboptimal model order selection and the effects of additive white Gaussion noise are addressed.

Optimal Signal Processing of Frequency-Stepped CW Radar Data

NASA Technical Reports Server (NTRS)

Ybarra, Gary A.; Wu, Shawkang M.; Bilbro, Griff L.; Ardalan, Sasan H.; Hearn, Chase P.; Neece, Robert T.

1995-01-01

An optimal signal processing algorithm is derived for estimating the time delay and amplitude of each scatterer reflection using a frequency-stepped CW system. The channel is assumed to be composed of abrupt changes in the reflection coefficient profile. The optimization technique is intended to maximize the target range resolution achievable from any set of frequency-stepped CW radar measurements made in such an environment. The algorithm is composed of an iterative two-step procedure. First, the amplitudes of the echoes are optimized by solving an overdetermined least squares set of equations. Then, a nonlinear objective function is scanned in an organized fashion to find its global minimum. The result is a set of echo strengths and time delay estimates. Although this paper addresses the specific problem of resolving the time delay between the two echoes, the derivation is general in the number of echoes. Performance of the optimization approach is illustrated using measured data obtained from an HP-851O network analyzer. It is demonstrated that the optimization approach offers a significant resolution enhancement over the standard processing approach that employs an IFFT. Degradation in the performance of the algorithm due to suboptimal model order selection and the effects of additive white Gaussion noise are addressed.

Robust PI and PID design for first- and second-order processes with zeros, time-delay and structured uncertainties

NASA Astrophysics Data System (ADS)

Parada, M.; Sbarbaro, D.; Borges, R. A.; Peres, P. L. D.

2017-01-01

The use of robust design techniques such as the one based on ? and ? for tuning proportional integral (PI) and proportional integral derivative (PID) controllers have been limited to address a small set of processes. This work addresses the problem by considering a wide set of possible plants, both first- and second-order continuous-time systems with time delays and zeros, leading to PI and PID controllers. The use of structured uncertainties to handle neglected dynamics allows to expand the range of processes to be considered. The proposed approach takes into account the robustness of the controller with respect to these structured uncertainties by using the small-gain theorem. In addition, improved performance is sought through the minimisation of an upper bound to the closed-loop system ? norm. A Lyapunov-Krasovskii-type functional is used to obtain delay-dependent design conditions. The controller design is accomplished by means of a convex optimisation procedure formulated using linear matrix inequalities. In order to illustrate the flexibility of the approach, several examples considering recycle compensation, reduced-order controller design and a practical implementation are addressed. Numerical experiments are provided in each case to highlight the main characteristics of the proposed design method.

Temporal response improvement for computed tomography fluoroscopy

NASA Astrophysics Data System (ADS)

Hsieh, Jiang

1997-10-01

Computed tomography fluoroscopy (CTF) has attracted significant attention recently. This is mainly due to the growing clinical application of CTF in interventional procedures, such as guided biopsy. Although many studies have been conducted for its clinical efficacy, little attention has been paid to the temporal response and the inherent limitations of the CTF system. For example, during a biopsy operation, when needle is inserted at a relatively high speed, the true needle position will not be correctly depicted in the CTF image due to the time delay. This could result in an overshoot or misplacement of the biopsy needle by the operator. In this paper, we first perform a detailed analysis of the temporal response of the CTF by deriving a set of equations to describe the average location of a moving object observed by the CTF system. The accuracy of the equations is verified by computer simulations and experiments. We show that the CT reconstruction process acts as a low pass filter to the motion function. As a result, there is an inherent time delay in the CTF process to the true biopsy needle motion and locations. Based on this study, we propose a generalized underscan weighting scheme which significantly improve the performance of CTF in terms of time lag and delay.

Advanced aeroservoelastic stabilization techniques for hypersonic flight vehicles

NASA Technical Reports Server (NTRS)

Chan, Samuel Y.; Cheng, Peter Y.; Myers, Thomas T.; Klyde, David H.; Magdaleno, Raymond E.; Mcruer, Duane T.

1992-01-01

Advanced high performance vehicles, including Single-Stage-To-Orbit (SSTO) hypersonic flight vehicles, that are statically unstable, require higher bandwidth flight control systems to compensate for the instability resulting in interactions between the flight control system, the engine/propulsion dynamics, and the low frequency structural modes. Military specifications, such as MIL-F-9490D and MIL-F-87242, tend to limit treatment of structural modes to conventional gain stabilization techniques. The conventional gain stabilization techniques, however, introduce low frequency effective time delays which can be troublesome from a flying qualities standpoint. These time delays can be alleviated by appropriate blending of gain and phase stabilization techniques (referred to as Hybrid Phase Stabilization or HPS) for the low frequency structural modes. The potential of using HPS for compensating structural mode interaction was previously explored. It was shown that effective time delay was significantly reduced with the use of HPS; however, the HPS design was seen to have greater residual response than a conventional gain stablized design. Additional work performed to advance and refine the HPS design procedure, to further develop residual response metrics as a basis for alternative structural stability specifications, and to develop strategies for validating HPS design and specification concepts in manned simulation is presented. Stabilization design sensitivity to structural uncertainties and aircraft-centered requirements are also assessed.

The Effectiveness of the Constant Time Delay Procedure in Teaching Pre-School Academic Skills to Children with Developmental Disabilities in a Small Group Teaching Arrangement

ERIC Educational Resources Information Center

Aldemir, Ozgul; Gursel, Oguz

2014-01-01

Children with developmental disabilities are trained using different teaching arrangements. One of these arrangements is called small-group teaching. It has been ascertained that a small-group teaching arrangement is more effective than a one-to-one teaching arrangement. In that sense, teaching academic skills to pre-school children in small-group…

Enabling a Prelinguistic Communicator with Autism to Use Picture Card as a Strategy for Repairing Listener Misunderstandings: A Case Study

ERIC Educational Resources Information Center

Ohtake, Yoshihisa; Wehmeyer, Michael; Uchida, Naomi; Nakaya, Akitaka; Yanagihara, Masafumi

2010-01-01

The purpose of this case study was to examine the effects of a time-delay prompting procedure on the acquisition of skills for repairing multiple listener misunderstandings. A prelinguistic student with autism was taught to use picture cards as a strategy to repair listener misunderstandings in a setting where the student had to ask the listener…

Evaluation of Flight Deck-Based Interval Management Crew Procedure Feasibility

NASA Technical Reports Server (NTRS)

Wilson, Sara R.; Murdoch, Jennifer L.; Hubbs, Clay E.; Swieringa, Kurt A.

2013-01-01

Air traffic demand is predicted to increase over the next 20 years, creating a need for new technologies and procedures to support this growth in a safe and efficient manner. The National Aeronautics and Space Administration's (NASA) Air Traffic Management Technology Demonstration - 1 (ATD-1) will operationally demonstrate the feasibility of efficient arrival operations combining ground-based and airborne NASA technologies. The integration of these technologies will increase throughput, reduce delay, conserve fuel, and minimize environmental impacts. The ground-based tools include Traffic Management Advisor with Terminal Metering for precise time-based scheduling and Controller Managed Spacing decision support tools for better managing aircraft delay with speed control. The core airborne technology in ATD-1 is Flight deck-based Interval Management (FIM). FIM tools provide pilots with speed commands calculated using information from Automatic Dependent Surveillance - Broadcast. The precise merging and spacing enabled by FIM avionics and flight crew procedures will reduce excess spacing buffers and result in higher terminal throughput. This paper describes a human-in-the-loop experiment designed to assess the acceptability and feasibility of the ATD-1 procedures used in a voice communications environment. This experiment utilized the ATD-1 integrated system of ground-based and airborne technologies. Pilot participants flew a high-fidelity fixed base simulator equipped with an airborne spacing algorithm and a FIM crew interface. Experiment scenarios involved multiple air traffic flows into the Dallas-Fort Worth Terminal Radar Control airspace. Results indicate that the proposed procedures were feasible for use by flight crews in a voice communications environment. The delivery accuracy at the achieve-by point was within +/- five seconds and the delivery precision was less than five seconds. Furthermore, FIM speed commands occurred at a rate of less than one per minute, and pilots found the frequency of the speed commands to be acceptable at all times throughout the experiment scenarios.

Airborne Four-Dimensional Flight Management in a Time-based Air Traffic Control Environment

NASA Technical Reports Server (NTRS)

Williams, David H.; Green, Steven M.

1991-01-01

Advanced Air Traffic Control (ATC) systems are being developed which contain time-based (4D) trajectory predictions of aircraft. Airborne flight management systems (FMS) exist or are being developed with similar 4D trajectory generation capabilities. Differences between the ATC generated profiles and those generated by the airborne 4D FMS may introduce system problems. A simulation experiment was conducted to explore integration of a 4D equipped aircraft into a 4D ATC system. The NASA Langley Transport Systems Research Vehicle cockpit simulator was linked in real time to the NASA Ames Descent Advisor ATC simulation for this effort. Candidate procedures for handling 4D equipped aircraft were devised and traffic scenarios established which required time delays absorbed through speed control alone or in combination with path stretching. Dissimilarities in 4D speed strategies between airborne and ATC generated trajectories were tested in these scenarios. The 4D procedures and FMS operation were well received by airline pilot test subjects, who achieved an arrival accuracy at the metering fix of 2.9 seconds standard deviation time error. The amount and nature of the information transmitted during a time clearance were found to be somewhat of a problem using the voice radio communication channel. Dissimilarities between airborne and ATC-generated speed strategies were found to be a problem when the traffic remained on established routes. It was more efficient for 4D equipped aircraft to fly trajectories with similar, though less fuel efficient, speeds which conform to the ATC strategy. Heavy traffic conditions, where time delays forced off-route path stretching, were found to produce a potential operational benefit of the airborne 4D FMS.

Mechanisms of motor recovery after subtotal spinal cord injury: insights from the study of mice carrying a mutation (WldS) that delays cellular responses to injury.

PubMed

Zhang, Z; Guth, L; Steward, O

1998-01-01

Partial lesions of the mammalian spinal cord result in an immediate motor impairment that recovers gradually over time; however, the cellular mechanisms responsible for the transient nature of this paralysis have not been defined. A unique opportunity to identify those injury-induced cellular responses that mediate the recovery of function has arisen from the discovery of a unique mutant strain of mice in which the onset of Wallerian degeneration is dramatically delayed. In this strain of mice (designated WldS for Wallerian degeneration, slow), many of the cellular responses to spinal cord injury are also delayed. We have used this experimental animal model to evaluate possible causal relationships between these delayed cellular responses and the onset of functional recovery. For this purpose, we have compared the time course of locomotor recovery in C57BL/6 (control) mice and in WldS (mutant) mice by hemisecting the spinal cord at T8 and evaluating locomotor function at daily postoperative intervals. The time course of locomotor recovery (as determined by the Tarlov open-field walking procedure) was substantially delayed in mice carrying the WldS mutation: C57BL/6 control mice began to stand and walk within 6 days (mean Tarlov score of 4), whereas mutant mice did not exhibit comparable locomotor function until 16 days postoperatively. (a) The rapid return of locomotor function in the C57BL/6 mice suggests that the recovery resulted from processes of functional plasticity rather than from regeneration or collateral sprouting of nerve fibers. (b) The marked delay in the return of locomotor function in WldS mice indicates that the processes of neuroplasticity are induced by degenerative changes in the damaged neurons. (c) These strains of mice can be effectively used in future studies to elucidate the specific biochemical and physiological alterations responsible for inducing functional plasticity and restoring locomotor function after spinal cord injury.

Map synchronization in optical communication systems

NASA Technical Reports Server (NTRS)

Gagliardi, R. M.; Mohanty, N.

1973-01-01

The time synchronization problem in an optical communication system is approached as a problem of estimating the arrival time (delay variable) of a known transmitted field. Maximum aposteriori (MAP) estimation procedures are used to generate optimal estimators, with emphasis placed on their interpretation as a practical system device, Estimation variances are used to aid in the design of the transmitter signals for best synchronization. Extension is made to systems that perform separate acquisition and tracking operations during synchronization. The closely allied problem of maintaining timing during pulse position modulation is also considered. The results have obvious application to optical radar and ranging systems, as well as the time synchronization problem.

Implementation of Nonlinear Control Laws for an Optical Delay Line

NASA Technical Reports Server (NTRS)

Hench, John J.; Lurie, Boris; Grogan, Robert; Johnson, Richard

2000-01-01

This paper discusses the implementation of a globally stable nonlinear controller algorithm for the Real-Time Interferometer Control System Testbed (RICST) brassboard optical delay line (ODL) developed for the Interferometry Technology Program at the Jet Propulsion Laboratory. The control methodology essentially employs loop shaping to implement linear control laws. while utilizing nonlinear elements as means of ameliorating the effects of actuator saturation in its coarse, main, and vernier stages. The linear controllers were implemented as high-order digital filters and were designed using Bode integral techniques to determine the loop shape. The nonlinear techniques encompass the areas of exact linearization, anti-windup control, nonlinear rate limiting and modal control. Details of the design procedure are given as well as data from the actual mechanism.

Computing the Lyapunov spectrum of a dynamical system from an observed time series

NASA Technical Reports Server (NTRS)

Brown, Reggie; Bryant, Paul; Abarbanel, Henry D. I.

1991-01-01

The paper examines the problem of accurately determining, from an observed time series, the Liapunov exponents for the dynamical system generating the data. It is shown that, even with very large data sets, it is clearly advantageous to utilize local neighborhood-to-neighborhood mappings with higher-order Taylor series rather than just local linear maps. This procedure is demonstrated on the Henon and Ikeda maps of the plane itself, the Lorenz system of three ordinary differential equations, and the Mackey-Glass delay differential equation.

Viscoelastic behavior and life-time predictions

NASA Technical Reports Server (NTRS)

Dillard, D. A.; Brinson, H. F.

1985-01-01

Fiber reinforced plastics were considered for many structural applications in automotive, aerospace and other industries. A major concern was and remains the failure modes associated with the polymer matrix which serves to bind the fibers together and transfer the load through connections, from fiber to fiber and ply to ply. An accelerated characterization procedure for prediction of delayed failures was developed. This method utilizes time-temperature-stress-moisture superposition principles in conjunction with laminated plate theory. Because failures are inherently nonlinear, the testing and analytic modeling for both moduli and strength is based upon nonlinear viscoelastic concepts.

Symbolic joint entropy reveals the coupling of various brain regions

NASA Astrophysics Data System (ADS)

Ma, Xiaofei; Huang, Xiaolin; Du, Sidan; Liu, Hongxing; Ning, Xinbao

2018-01-01

The convergence and divergence of oscillatory behavior of different brain regions are very important for the procedure of information processing. Measurements of coupling or correlation are very useful to study the difference of brain activities. In this study, EEG signals were collected from ten subjects under two conditions, i.e. eyes closed state and idle with eyes open. We propose a nonlinear algorithm, symbolic joint entropy, to compare the coupling strength among the frontal, temporal, parietal and occipital lobes and between two different states. Instead of decomposing the EEG into different frequency bands (theta, alpha, beta, gamma etc.), the novel algorithm is to investigate the coupling from the entire spectrum of brain wave activities above 4Hz. The coupling coefficients in two states with different time delay steps are compared and the group statistics are presented as well. We find that the coupling coefficient of eyes open state with delay consistently lower than that of eyes close state across the group except for one subject, whereas the results without delay are not consistent. The differences between two brain states with non-zero delay can reveal the intrinsic inter-region coupling better. We also use the well-known Hénon map data to validate the algorithm proposed in this paper. The result shows that the method is robust and has a great potential for other physiologic time series.

Facility-based constraints to exchange transfusions for neonatal hyperbilirubinemia in resource-limited settings

PubMed Central

Mabogunje, Cecilia A; Olaifa, Sarah M; Olusanya, Bolajoko O

2016-01-01

Several clinical guidelines for the management of infants with severe neonatal hyperbilirubinemia recommend immediate exchange transfusion (ET) when the risk or presence of acute bilirubin encephalopathy is established in order to prevent chronic bilirubin encephalopathy or kernicterus. However, the literature is sparse concerning the interval between the time the decision for ET is made and the actual initiation of ET, especially in low- and middle-income countries (LMICs) with significant resource constraints but high rates of ET. This paper explores the various stages and potential delays during this interval in complying with the requirement for immediate ET for the affected infants, based on the available evidence from LMICs. The vital role of intensive phototherapy, efficient laboratory and logistical support, and clinical expertise for ET are highlighted. The challenges in securing informed parental consent, especially on religious grounds, and meeting the financial burden of this emergency procedure to facilitate timely ET are examined. Secondary delays arising from post-treatment bilirubin rebound with intensive phototherapy or ET are also discussed. These potential delays can compromise the effectiveness of ET and should provide additional impetus to curtail avoidable ET in LMICs. PMID:27170928

CT scanning in stroke patients: meeting the challenge in the remote and rural district general hospital.

PubMed

Todd, A W; Anderson, E M

2009-05-01

National audit data allow crude comparison between centres and indicate that most Scottish hospitals fail to meet current guidelines for CT scanning of the brain in stroke patients. This study identifies some of the reasons for delay in performing CT scans in a largely rural population. This audit study assesses the delays from onset of symptoms, time of admission and request received to CT scan in stroke patients for three different in-patient groups as well as those managed in the community. The reasons for delay in CT scanning varied between different patient groups but for one group of in-patients, changes in booking procedure and introduction of a second CT scanner increased the proportion scanned within 48 hours of request from 65% to 96%. Further developments including the introduction of Saturday and Sunday routine CT scanning, radiologist reporting from home and additional CT scanners placed in remote hospitals may be expected to improve these figures further. Target times of three hours from onset of symptoms to scan to allow thrombolysis may however be impossible to meet for all stroke patients in rural areas.

Psychophysics of remembering.

PubMed Central

White, K G; Wixted, J T

1999-01-01

We present a new model of remembering in the context of conditional discrimination. For procedures such as delayed matching to sample, the effect of the sample stimuli at the time of remembering is represented by a pair of Thurstonian (normal) distributions of effective stimulus values. The critical assumption of the model is that, based on prior experience, each effective stimulus value is associated with a ratio of reinforcers obtained for previous correct choices of the comparison stimuli. That ratio determines the choice that is made on the basis of the matching law. The standard deviations of the distributions are assumed to increase with increasing retention-interval duration, and the distance between their means is assumed to be a function of other factors that influence overall difficulty of the discrimination. It is a behavioral model in that choice is determined by its reinforcement history. The model predicts that the biasing effects of the reinforcer differential increase with decreasing discriminability and with increasing retention-interval duration. Data from several conditions using a delayed matching-to-sample procedure with pigeons support the predictions. PMID:10028693

A 20 year review of punishment and alternative methods to treat problem behaviors in developmentally delayed persons.

PubMed

Matson, J L; Taras, M E

1989-01-01

Relevant journals were reviewed (n = 23) for a 20 year period (1967 to 1987) to assess the status of treatments for severe behavior problems of developmentally delayed persons. A hand search of journals was made; 382 studies were identified. Procedures were analyzed by problem behaviors treated, side effects reported, whether the procedure involved painful stimuli, nonpainful stimuli, food satiation, positive procedures, extinction or combinations of methods. The number of studies reported yearly was also plotted. The implication of these data for federal and state policy makers and for treatment programs dealing with difficult to treat clients is discussed.

A GIS Procedure to Monitor PWV During Severe Meteorological Events

NASA Astrophysics Data System (ADS)

Ferrando, I.; Federici, B.; Sguerso, D.

2016-12-01

As widely known, the observation of GNSS signal's delay can improve the knowledge of meteorological phenomena. The local Precipitable Water Vapour (PWV), which can be easily derived from Zenith Total Delay (ZTD), Pressure (P) and Temperature (T) (Bevis et al., 1994), is not a satisfactory parameter to evaluate the occurrence of severe meteorological events. Hence, a GIS procedure, called G4M (GNSS for Meteorology), has been conceived to produce 2D PWV maps with high spatial and temporal resolution (1 km and 6 minutes respectively). The input data are GNSS, P and T observations not necessarily co-located coming from existing infrastructures, combined with a simplified physical model, owned by the research group.On spite of the low density and the different configurations of GNSS, P and T networks, the procedure is capable to detect severe meteorological events with reliable results. The procedure has already been applied in a wide and orographically complex area covering approximately the north-west of Italy and the French-Italian border region, to study two severe meteorological events occurred in Genoa (Italy) and other meteorological alert cases. The P, T and PWV 2D maps obtained by the procedure have been compared with the ones coming from meteorological re-analysis models, used as reference to obtain statistics on the goodness of the procedure in representing these fields. Additionally, the spatial variability of PWV was taken into account as indicator for representing potential critical situations; this index seems promising in highlighting remarkable features that precede intense precipitations. The strength and originality of the procedure lie into the employment of existing infrastructures, the independence from meteorological models, the high adaptability to different networks configurations, and the ability to produce high-resolution 2D PWV maps even from sparse input data. In the next future, the procedure could also be set up for near real-time applications.

The continuing problem of missed test results in an integrated health system with an advanced electronic medical record.

PubMed

Wahls, Terry; Haugen, Thomas; Cram, Peter

2007-08-01

Missed results can cause needless treatment delays. However, there is little data about the magnitude of this problem and the systems that clinics use to manage test results. Surveys about potential problems related to test results management were developed and administered to clinical staff in a regional Veterans Administration (VA) health care network. The provider survey, conducted four times between May 2005 and October 2006, sampling VA staff physicians, physician assistants, nurse practitioners, and internal medicine trainees, asked questions about the frequency of missed results and diagnosis or treatment delays seen in the antecedent two weeks in their clinics, or if a trainee, the antecedent month. Clinical staff survey response rate was 39% (143 of 370), with 40% using standard operating procedures to manage test results. Forty-four percent routinely reported all results to patients. The provider survey response rate was 50% (441 of 884) overall, with responses often (37% overall; range 29% to 46%) indicating they had seen patients with diagnosis or treatment delays attributed to a missed result; 15% reported two or more such encounters. Even in an integrated health system with an advanced electronic medical record, missed test results and associated diagnosis or treatment delays are common. Additional study and measures of missed results and associated treatment delays are needed.

Facilitating tolerance of delayed reinforcement during functional communication training.

PubMed

Fisher, W W; Thompson, R H; Hagopian, L P; Bowman, L G; Krug, A

2000-01-01

Few clinical investigations have addressed the problem of delayed reinforcement. In this investigation, three individuals whose destructive behavior was maintained by positive reinforcement were treated using functional communication training (FCT) with extinction (EXT). Next, procedures used in the basic literature on delayed reinforcement and self-control (reinforcer delay fading, punishment of impulsive responding, and provision of an alternative activity during reinforcer delay) were used to teach participants to tolerate delayed reinforcement. With the first case, reinforcer delay fading alone was effective at maintaining low rates of destructive behavior while introducing delayed reinforcement. In the second case, the addition of a punishment component reduced destructive behavior to near-zero levels and facilitated reinforcer delay fading. With the third case, reinforcer delay fading was associated with increases in masturbation and head rolling, but prompting and praising the individual for completing work during the delay interval reduced all problem behaviors and facilitated reinforcer delay fading.

Adverse Event Rates Associated with Transforaminal and Interlaminar Epidural Steroid Injections: A Multi-Institutional Study.

PubMed

El-Yahchouchi, Christine A; Plastaras, Christopher T; Maus, Timothy P; Carr, Carrie M; McCormick, Zachary L; Geske, Jennifer R; Smuck, Matthew; Pingree, Matthew J; Kennedy, David J

2016-02-01

Transforaminal epidural steroid injections (TFESI) have demonstrated efficacy and effectiveness in treatment of radicular pain. Despite little evidence of efficacy/effectiveness, interlaminar epidural steroid injections (ILESI) are advocated by some as primary therapy for radicular pain due to purported greater safety. To assess immediate and delayed adverse event rates of TFESI and ILESI injections at three academic medical centers utilizing International Spine Intervention Society practice guidelines. Quality assurance databases from a Radiology and two physical medicine and rehabilitation (PM&R) practices were interrogated. Medical records were reviewed, verifying immediate and delayed adverse events. There were no immediate major adverse events of neurologic injury or hemorrhage in 16,638 consecutive procedures in all spine segments (14,956 TFESI; 1,682 ILESI). Vasovagal reactions occurred in 1.2% of procedures, more frequently (P = 0.004) in TFESI (1.3%) than ILESI (0.5%). Dural punctures occurred in 0.06% of procedures, more commonly after ILESI (0.2% vs 0.04%, P = 0.006). Delayed follow up on PM&R patients (92.5% and 78.5, next business day) and radiology patients (63.1%, 2 weeks) identified no major adverse events of neurologic injury, hemorrhage, or infection. There were no significant differences in delayed minor adverse event rates. Central steroid response (sleeplessness, flushing, nonpositional headache) was seen in 2.6% of both TFESI and ILESI patients. 2.1% of TFESI and 1.8% of ILESI patients reported increased pain. No long-term sequelae were seen from any immediate or delayed minor adverse event. Both transforaminal and ILESI are safely performed with low immediate and delayed adverse event rates when informed by evidence-based procedural guidelines. By demonstrating comparable safety, this study suggests that the choice between ILESI and TFESIs can be based on documented efficacy and effectiveness and not driven by safety concerns.

Bone augmentation of the osteo-odonto alveolar lamina in MOOKP--will it delay laminar resorption?

PubMed

Iyer, Geetha; Srinivasan, Bhaskar; Agarwal, Shweta; Rishi, Ekta; Rishi, Pukhraj; Rajan, Gunaseelan; Shanmugasundaram, Shanmugasundaram

2015-07-01

We aimed to describe a new technique and analyse the early outcomes of augmenting the canine tooth using a mandibular bone graft in an attempt to delay or retard the process of laminar resorption following the modified osteo odonto keratoprosthesis (MOOKP) procedure. This was a retrospective case series. Eyes that underwent the bone augmentation procedure between December 2012 and February 2014 were retrospectively analysed. The procedure, performed by the oromaxillofacial surgeon, involved securing a mandibular bone graft beneath the periosteum on the labial aspect of the canine tooth chosen to be harvested for the MOOKP procedure. This procedure was performed simultaneously with the Stage 1 A of the MOOKP. Three months later, the tooth was harvested and fashioned into the osteo-odonto alveolar lamina similar to the method described in the Rome-Vienna Protocol. The bone augmentation procedure was performed in 11 eyes (five SJS/ six chemical injuries). The mean follow-up after Stage 2 of MOOKP procedure in these eyes was 7.45 months (2 to 20 months). Complications noted were peripheral laminar exposure (three eyes-SJS) and bone graft exposure and necrosis in the mouth (nine-SJS). No evidence of clinical laminar resorption was noted in any of the eyes. Laminar resorption in MOOKP can lead to vision and globe threatening complications due to the consequent cylinder instability and chances of extrusion. Augmenting the bone on the labial aspect of the canine tooth might have a role to play in delaying or preventing laminar resorption.

Super-Latent Inhibition of Conditioned Taste Preference with a Long Retention Interval

ERIC Educational Resources Information Center

De la Casa, L. G.; Marquez, R.; Lubow, R. E.

2009-01-01

A long delay inserted between conditioning and test phases of a 3-stage Latent Inhibition (LI) procedure produces differential effects on LI depending on the delay context. Thus, enhanced LI has been obtained when the delay is spent in a context that is different from the remaining experimental contexts, but not when it is the same. The present…

The Effect of Delayed Responding on Stroop-Like Task Performance among Preschoolers

ERIC Educational Resources Information Center

Montgomery, Derek E.; Fosco, Whitney

2012-01-01

Forty-four preschoolers completed 2 conditions of a Stroop-like procedure (e.g., saying "boat" for car and "car" for boat) that differed in whether a 3-s delay was imposed before responding. The test card was visible during the delay period for half of the children and occluded for the other children. Preschoolers' interference control was…

Timing Calibration of the NEMO Optical Sensors

NASA Astrophysics Data System (ADS)

Circella, M.; de Marzo, C.; Megna, R.; Ruppi, M.

2006-04-01

This paper describes the timing calibration system for the NEMO underwater neutrino telescope. The NEMO Project aims at the construction of a km3 detector, equipped with a large number of photomultipliers, in the Mediterranean Sea. We foresee a redundant system to perform the time calibration of our apparatus: 1) A two-step procedure for measuring the offsets in the time measurements of the NEMO optical sensors, so as to measure separately the time delay for the synchronization signals to reach the offshore electronics and the response time of the photomultipliers to calibration signals delivered from optical pulsers through an optical fibre distribution system; 2) an all-optical procedure for measuring the differences in the time offsets of the different optical modules illuminated by calibration pulses. Such a system can be extended to work for a very large apparatus, even for complex arrangements of widely spaced sensors. The NEMO prototyping activities ongoing at a test site off the coast of Sicily will allow the system described in this work to be operated and tested in situ next year.

Automatic recording of mediating behavior in delayed matching- and nonmatching-to-position procedures in rats.

PubMed

Panlilio, Leigh V; Yasar, Sevil; Thorndike, Eric B; Goldberg, Steven R; Schindler, Charles W

2011-03-01

Delayed matching-to-position and nonmatching-to-position procedures are widely used to model working memory in rodents. Mediating behavior-which enhances performance but is not explicitly required by the task-is generally considered an obstacle to the measurement of memory, but often occurs despite attempts to prevent it. The ubiquitous nature of mediating behavior suggests it might be analogous to rehearsal, an important component of learning and memory in humans. The aim was to study an easily recordable, rehearsal-like mediating response in rats under baseline conditions and after treatment with amnestic drugs [scopolamine (0.1-0.3 mg/kg) and delta-9-tetrahydrocannabinol (THC; 1-5.6 mg/kg)]. Lighted nosepoke holes were used to present position cues and record delayed matching or nonmatching responses. Performance of a distractor task was required to prevent simply waiting at the correct choice, but the nosepoke holes were left accessible during the delay. Each rat trained with the nonmatching task exhibited one of two mediating "strategies" that increased the odds of a correct choice: responding in the to-be-correct hole during the delay or responding in the opposite hole during the delay. Rats trained with the matching task all showed the former strategy. Treatment with scopolamine disrupted performance of the mediating response. Scopolamine and THC both decreased the effectiveness of the mediating response, increasing errors even on trials when the "appropriate" mediating behavior did occur. The procedures and data analysis approach used here provide an objective, automated means of measuring mediating behavior, which might be useful as an animal model of memory rehearsal.

Planned Variation in Preanalytical Conditions to Evaluate Biospecimen Stability in the National Children’s Study (NCS)

PubMed Central

Mechanic, Leah; Mendez, Armando; Merrill, Lori; Rogers, John; Layton, Marnie; Todd, Deborah; Varanasi, Arti; O’Brien, Barbara; Meyer, William A.; Zhang, Ming; Schleicher, Rosemary L.; Moye, Jack

2014-01-01

BACKGROUND Preanalytical conditions encountered during collection, processing, and storage of biospecimens may influence laboratory results. The National Children’s Study (NCS) is a planned prospective cohort study of 100,000 families to examine the influence of a wide variety of exposures on child health. In developing biospecimen collection, processing, and storage procedures for the NCS, we identified several analytes of different biochemical categories for which it was unclear to what extent deviations from NCS procedures could influence measurement results. METHODS A pilot study was performed to examine effects of preanalytic sample handling conditions (delays in centrifugation, freezing delays, delays in separation from cells, additive delay, and tube type) on concentrations of eight different analytes. 2,825 measurements were made to assess 15 unique combinations of analyte and handling conditions in blood collected from 151 women of childbearing age (≥20 individuals per handling condition). RESULTS The majority of analytes were stable under the conditions evaluated. However, levels of plasma interleukin-6 and serum insulin were decreased in response to sample centrifugation delays of up to 5.5 hours post collection (P<0.0001). In addition, delays in freezing centrifuged plasma samples (comparing 24, 48 and 72 hours to immediate freezing) resulted in increased levels of adrenocorticotropic hormone (P=0.0014). CONCLUSIONS Determining stability of proposed analytes in response to preanalytical conditions and handling helps to ensure high-quality specimens for study now and in the future. The results inform development of procedures, plans for measurement of analytes, and interpretation of laboratory results. PMID:23924524

Effects Of Methylphenidate And Morphine On Delay-Discount Functions Obtained Within Sessions

PubMed Central

Pitts, Raymond C; McKinney, A. Patrick

2005-01-01

Four rats responded under a “self-control” procedure designed to obtain delay-discount functions within sessions. Each session consisted of seven blocks, with seven trials within each block. Each block consisted of two initial forced-choice trials followed by five free-choice trials. On choice trials, the rats could press either of two retractable levers. A press on one lever was followed by presentation of a smaller reinforcer (a single dipper presentation of a sucrose solution); a press on the other lever was followed by presentation of a larger reinforcer (four consecutive dipper presentations). The delay associated with the smaller reinforcer always was 0 s, whereas the signaled delay associated with the larger reinforcer increased across blocks (from 0 to 50 s). Under these conditions, the percentage of choices of the larger reinforcer decreased across blocks, and relatively reliable delay-discount functions were obtained within sessions. Doses of methylphenidate (1.0 to 17.0 mg/kg) and morphine (0.3 to 17.0 mg/kg) were then administered prior to selected sessions. Typically, intermediate doses of methylphenidate shifted the discount functions to the right (increased choices of the larger reinforcer). For 2 of the rats, this effect was pronounced; for the other 2 rats, this effect occurred after the range of delays for the larger reinforcer was decreased (0 to 20 s). On the other hand, in most cases morphine produced a slight leftward shift in the discount function (decreased choices of the larger reinforcer). The present procedure appears to be a useful and efficient method to characterize drug effects on an entire delay-discount function. As with many procedures used to study self-control choices, however, sources of control other than reinforcement delay and amount may have been operating in the present study, and these sources must be considered when interpreting drug effects. PMID:16047609

A closer look at the concept of regional clocks for Precise Point Positioning

NASA Astrophysics Data System (ADS)

Weber, Robert; Karabatic, Ana; Thaler, Gottfried; Abart, Christoph; Huber, Katrin

2010-05-01

Under the precondition of at least two successfully tracked signals at different carrier frequencies we may obtain their ionosphere free linear combination. By introducing approximate values for geometric effects like orbits and tropospheric delay as well as an initial bias parameter N per individual satellite we can solve for the satellite clock with respect to the receiver clock. Noting, that residual effects like orbit errors, remaining tropospheric delays and a residual bias parameter map into these parameters, this procedure leaves us with a kind of virtual clock differences. These clocks cover regional effects and are therefore clearly correlated with clocks at nearby station. Therefore we call these clock differences, which are clearly different from clock solutions provided for instance by IGS, the "regional clocks". When introducing the regional clocks obtained from real-time data of a GNSS reference station network we are able to process the coordinates of a nearby isolated station via a PPP .In terms of PPP-convergence time which will be reduced down to 30 minutes or less, this procedure is clearly favorable. The accuracy is quite comparable with state of the art PPP procedures. Nevertheless, this approach cannot compete in fixing times with double-difference approaches but the correlation holds over hundreds of kilometers distance to our master station and the clock differences can easily by obtained, even in real-time. This presentation provides preliminary results of the project RA-PPP. RA-PPP is a research project financed by the Federal Ministry for Transport, Innovation and Technology, managed by the Austrian Research Promotion Agency (FFG) in the course of the 6th call of the Austrian Space Application Program (ASAP). RA-PPP stands for Rapid Precise Point Positioning, which denotes the wish for faster and more accurate algorithms for PPP. The concept of regional clocks which will be demonstrated in detail in this presentation is one out of 4 concepts to be evaluated in this project.

Maternal Near-Miss Due to Unsafe Abortion and Associated Short-Term Health and Socio-Economic Consequences in Nigeria

PubMed Central

Prada, Elena; Bankole, Akinrinola; Oladapo, Olufemi T.; Awolude, Olutosin A.; Adewole, Isaac F.; Onda, Tsuyoshi

2016-01-01

Little is known about maternal near-miss (MNM) due to unsafe abortion in Nigeria. We used the WHO criteria to identify near-miss events and the proportion due to unsafe abortion among women of childbearing age in eight large secondary and tertiary hospitals across the six geo-political zones. We also explored the characteristics of women with these events, delays in seeking care and the short-term socioeconomic and health impacts on women and their families. Between July 2011 and January 2012, 137 MNM cases were identified of which 13 or 9.5% were due to unsafe abortions. Severe bleeding, pain and fever were the most common immediate abortion complications. On average, treatment of MNM due to abortion costs six times more than induced abortion procedures. Unsafe abortion and delays in care seeking are important contributors to MNM. Programs to prevent unsafe abortion and delays in seeking postabortion care are urgently needed to reduce abortion related MNM in Nigeria. PMID:26506658

Evidence for opponent-process actions of intravenous cocaine.

PubMed

Ettenberg, A; Raven, M A; Danluck, D A; Necessary, B D

1999-11-01

The present experiment was devised to test a prediction of the Opponent-Process Theory of drug action. This theory presumes that the initial affective experience of a subject treated with cocaine would be diametrically different immediately after administration compared to some point later in time when the positive impact of the drug had subsided. A conditioned place-preference procedure was employed in which a novel environment was paired with the effects of cocaine either immediately after, 5 min after, or 15 min after an intravenous injection of 0.75 mg/kg cocaine. It was hypothesized that animals would come to prefer environments associated with the immediate positive effects of cocaine and avoid environments associated with the drug's subsequent negative effects. The results confirmed this hypothesis. While the 0-min delay and 5-min delay groups exhibited conditioned preferences for the cocaine-paired environment, the 15-min delay group came to avoid the side of the preference apparatus paired with cocaine. These data, therefore, serve as additional support for an Opponent-Process account of cocaine's actions.

Maternal Near-Miss Due to Unsafe Abortion and Associated Short-Term Health and Socio-Economic Consequences in Nigeria.

PubMed

Prada, Elena; Bankole, Akinrinola; Oladapo, Olufemi T; Awolude, Olutosin A; Adewole, Isaac F; Onda, Tsuyoshi

2015-06-01

Little is known about maternal near-miss (MNM) due to unsafe abortion in Nigeria. We used the WHO criteria to identify near-miss events and the proportion due to unsafe abortion among women of childbearing age in eight large secondary and tertiary hospitals across the six geo-political zones. We also explored the characteristics of women with these events, delays in seeking care and the short-term socioeconomic and health impacts on women and their families. Between July 2011 and January 2012, 137 MNM cases were identified of which 13 or 9.5% were due to unsafe abortions. Severe bleeding, pain and fever were the most common immediate abortion complications. On average, treatment of MNM due to abortion costs six times more than induced abortion procedures. Unsafe abortion and delays in care seeking are important contributors to MNM. Programs to prevent unsafe abortion and delays in seeking postabortion care are urgently needed to reduce abortion related MNM in Nigeria.

Outcomes in Patients With Hemophilia and von Willebrand Disease Undergoing Invasive or Surgical Procedures.

PubMed

Chapin, John; Bamme, Jaqueline; Hsu, Fraustina; Christos, Paul; DeSancho, Maria

2017-03-01

Adults with hemophilia A (HA), hemophilia B (HB), and von Willebrand disease (VWD) frequently require surgery and invasive procedures. However, there is variability in perioperative management guidelines. We describe our periprocedural outcomes in this setting. A retrospective chart review from January 2006 to December 2012 of patients with HA, HB, and VWD undergoing surgery or invasive procedures was conducted. Type of procedures, management including the use of continuous factor infusion, and administration of antifibrinolytics were reviewed. Adverse outcomes were defined as acute bleeding (<48 hours), delayed bleeding (≥48 hours), transfusion, inhibitor development, and thrombosis. We identified 59 patients with HA and HB. In all, 24 patients had severe hemophilia and 12 had mild/moderate hemophilia. Twelve patients had inhibitors. There were also 5 female carriers of HA and 6 patients with VWD. There were 34 major surgeries (26 orthopedic, 8 nonorthopedic) and 129 minor surgeries. Continuous infusion was used in 55.9% of major surgeries versus 8.5% of minor surgeries. Antifibrinolytics were administered in 14.7% of major surgeries versus 23.2% of minor surgeries. In all, 4 patients developed acute bleeding and 10 patients developed delayed bleeding. Delayed bleeding occurred in 28.6% of genitourinary procedures and in 16.1% of dental procedures. Five patients acquired an inhibitor and 2 had thrombosis. In conclusion, patients with HA, HB, or VWD had similar rates of adverse outcomes when undergoing minor surgeries or major surgeries. This finding underscores the importance of an interdisciplinary management and procedure-specific guidelines for patients with hemophilia and VWD prior to even minor invasive procedures.

Delay-tunable gap-soliton-based slow-light system

NASA Astrophysics Data System (ADS)

Mok, Joe T.; de Sterke, C. Martijn; Eggleton, Benjamin J.

2006-12-01

We numerically and analytically evaluate the delay of solitons propagating slowly, and without broadening, in an apodized Bragg grating. Simulations indicate that a 100 mm Bragg grating with Δn = 10-3 can delay sub-nanosecond pulses by nearly 20 pulse widths without any change in the output pulse width. Delay tunability is achieved by simultaneously adjusting the launch power and detuning. A simple analytic model is developed to describe the monotonic dependence of delay on Δn and compared with simulations. As the intensity may be greatly enhanced due to a reduced velocity, a procedure for improving the delay while avoiding material damage is outlined.

Development of the L-1011 four-dimensional flight management system

NASA Technical Reports Server (NTRS)

Lee, H. P.; Leffler, M. F.

1984-01-01

The development of 4-D guidance and control algorithms for the L-1011 Flight Management System is described. Four-D Flight Management is a concept by which an aircraft's flight is optimized along the 3-D path within the constraints of today's ATC environment, while its arrival time is controlled to fit into the air traffic flow without incurring or causing delays. The methods developed herein were designed to be compatible with the time-based en route metering techniques that were recently developed by the Dallas/Fort Worth and Denver Air Route Traffic Control Centers. The ensuing development of the 4-D guidance algorithms, the necessary control laws and the operational procedures are discussed. Results of computer simulation evaluation of the guidance algorithms and control laws are presented, along with a description of the software development procedures utilized.

Delayed Infective Endocarditis with Mycotic Aneurysm Rupture below the Mechanical Valved Conduit after the Bentall Procedure

PubMed Central

Chen, Mei-Ling; Chen, Michael Y.; Yin, Wei-Hsian; Wei, Jeng; Wang, Ji-Hung

2014-01-01

The Bentall procedure is the gold standard for treating aortic dissection complicated with valvular and ascending aorta disease. Recent results for this procedure have been excellent; nearly 100% of patients remain free of infective endocarditis in long-term follow-up. We report a case of delayed Streptococcus agalactiae infective endocarditis complicated by mycotic aneurysm in a man who had undergone the Bentall procedure with a mechanical valve conduit 15 years previously. The mycotic aneurysm was located in the remnant aortic root, below the mechanical valve conduit, and later ruptured into the right atrium. The patient was treated conservatively and survived the acute period. Later, the aortic root defect was repaired successfully by means of a hybrid technique using a Amplatzer duct occluder. PMID:27122809

Energy management - The delayed flap approach

NASA Technical Reports Server (NTRS)

Bull, J. S.

1976-01-01

Flight test evaluation of a Delayed Flap approach procedure intended to provide reductions in noise and fuel consumption is underway using the NASA CV-990 test aircraft. Approach is initiated at a high airspeed (240 kt) and in a drag configuration that allows for low thrust. The aircraft is flown along the conventional ILS glide slope. A Fast/Slow message display signals the pilot when to extend approach flaps, landing gear, and land flaps. Implementation of the procedure in commercial service may require the addition of a DME navigation aid co-located with the ILS glide slope transmitter. The Delayed Flap approach saves 250 lb of fuel over the Reduced Flap approach, with a 95 EPNdB noise contour only 43% as large.

Gangrene of the oesophago-gastric junction caused by strangulated hiatal hernia: operative challenge or surgical dead end.

PubMed

Schweigert, M; Dubecz, A; Ofner, D; Stein, H J

2014-06-01

Gangrene of the oesophago-gastric junction due to incarcerated hiatal hernia is an extremely uncommon emergency situation which was first recognized in the late nineteenth century. Early symptoms are mainly unspecific and so diagnosis is often considerably delayed. Aim of the study is to share experience in dealing with this devastating condition. We encountered three male patients with gangrene of the oesophago-gastric junction caused by strangulated hiatal hernia within the last years. Clinical symptoms, surgical procedures and outcomes were retrospectively analyzed. Furthermore, we provide a history outline on the evolving surgical management from the preliminary reports of the nineteenth century up to modern times. Early symptoms were massive vomiting accompanied by retrosternal and epigastric pain. Hiatal hernia was already known in all patients. Nevertheless, clinical presentation was initially misdiagnosed as cardiovascular disorders. Upon emergency laparotomy gangrene of the oesophago-gastric junction was obvious while in one case even necrosis of the whole stomach occurred after considerable delayed diagnosis. Transmediastinal esophagectomy with resection of the proximal stomach and gastric pull up with cervical anastomosis was performed in two cases. Oesophago-gastrectomy with delayed reconstruction by retrosternal colonic interposition was mandatory in the case of complete gastric gangrene. Finally all sufferers recuperated well. Strangulation of hiatal hernia with subsequent gangrene of the oesophago-gastric junction is a life-threatening condition. Straight diagnosis is mandatory to avoid further necrosis of the proximal gastrointestinal tract as well as severe septic disease. Surgical strategies have considerably varied throughout the last 100 years. In our opinion transmediastinal oesophagectomy with interposition of a gastric tube and cervical anastomosis should be the procedure of choice if the distal stomach is still viable. Otherwise oesophago-gastrectomy is unavoidable. Delayed cervical anastomosis or reconstruction is advisable in instable, septic patients.

Constructing an episode of care from acute hospitalization records for studying effects of timing of hip fracture surgery.

PubMed

Sheehan, Katie J; Sobolev, Boris; Guy, Pierre; Bohm, Eric; Hellsten, Erik; Sutherland, Jason M; Kuramoto, Lisa; Jaglal, Susan

2016-02-01

Episodes of care defined by the event of hip fracture surgery are widely used for the assessment of surgical wait times and outcomes. However, this approach does not consider nonoperative deaths, implying that survival time begins at the time of procedure. This approach makes treatment effect implicitly conditional on surviving to treatment. The purpose of this article is to describe a novel conceptual framework for constructing an episode of hip fracture care to fully evaluate the incidence of adverse events related to time after admission for hip fracture. This admission-based approach enables the assessment of the full harm of delay by including deaths while waiting for surgery, not just deaths after surgery. Some patients wait until their conditions are optimized for surgery, whereas others have to wait until surgical service becomes available. We provide definitions, linkage rules, and algorithms to capture all hip fracture patients and events other than surgery. Finally, we discuss data elements for stratifying patients according to administrative factors for delay to allow researchers and policymakers to determine who will benefit most from expedited access to surgery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

A variation of noncontingent reinforcement in the treatment of aberrant behavior.

PubMed

Britton, L N; Carr, J E; Kellum, K K; Dozier, C L; Weil, T M

2000-01-01

We examined the effectiveness of a variation of noncontingent reinforcement (NCR) that incorporated a stimulus-delay procedure in the reduction of aberrant behavior maintained by positive reinforcement. Functional analyses for three individuals diagnosed with developmental disabilities indicated that their behaviors were maintained by positive reinforcement: one in the form of access to a tangible item, another by attention, and the third by physical contact. We implemented NCR with the delay procedure with two participants using reversal designs to evaluate effects. We also compared this NCR variation and DRO with the third participant to evaluate reinforcer-delivery rates. The variation of NCR was successful in reducing all aberrant behavior to near-zero levels. A comparison of reinforcer delivery between NCR with the stimulus-delay procedure and DRO demonstrated that the participant accessed more reinforcement with NCR. Results are discussed in the context of enhancing decelerative interventions with emphases on minimizing response effort for caregivers and maximizing access to reinforcement for the individuals.

Antimatched Electromagnetic Metasurfaces for Broadband Arbitrary Phase Manipulation in Reflection

DOE PAGES

Tsilipakos, Odysseas; Koschny, Thomas; Soukoulis, Costas M.

2018-03-21

Metasurfaces impart phase discontinuities on impinging electromagnetic waves that are typically limited to 0-2π. Here, we demonstrate that multiresonant metasurfaces can break free from this limitation and supply arbitrarily large, tunable time delays over ultrawide bandwidths. As such, ultrathin metasurfaces can act as the equivalent of thick bulk structures by emulating the multiple geometric resonances of three-dimensional systems that originate from phase accumulation with effective material resonances implemented on the surface itself via suitable subwavelength meta-atoms. We describe a constructive procedure for defining the required sheet admittivities of such metasurfaces. Importantly, the proposed approach provides an exactly linear phase responsemore » so that broadband pulses can experience the desired group delay without any distortion of the pulse shape. We focus on operation in reflection by exploiting an antimatching condition, satisfied by interleaved electric and magnetic Lorentzian resonances in the surface admittivities, which completely zeroes out transmission through the metasurface. As a result, the proposed metasurfaces can perfectly reflect a broadband pulse imparting a prescribed group delay. The group delay can be tuned by modifying the implemented resonances, thus opening up diverse possibilities in the temporal applications of metasurfaces.« less

Antimatched Electromagnetic Metasurfaces for Broadband Arbitrary Phase Manipulation in Reflection

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

Tsilipakos, Odysseas; Koschny, Thomas; Soukoulis, Costas M.

Metasurfaces impart phase discontinuities on impinging electromagnetic waves that are typically limited to 0-2π. Here, we demonstrate that multiresonant metasurfaces can break free from this limitation and supply arbitrarily large, tunable time delays over ultrawide bandwidths. As such, ultrathin metasurfaces can act as the equivalent of thick bulk structures by emulating the multiple geometric resonances of three-dimensional systems that originate from phase accumulation with effective material resonances implemented on the surface itself via suitable subwavelength meta-atoms. We describe a constructive procedure for defining the required sheet admittivities of such metasurfaces. Importantly, the proposed approach provides an exactly linear phase responsemore » so that broadband pulses can experience the desired group delay without any distortion of the pulse shape. We focus on operation in reflection by exploiting an antimatching condition, satisfied by interleaved electric and magnetic Lorentzian resonances in the surface admittivities, which completely zeroes out transmission through the metasurface. As a result, the proposed metasurfaces can perfectly reflect a broadband pulse imparting a prescribed group delay. The group delay can be tuned by modifying the implemented resonances, thus opening up diverse possibilities in the temporal applications of metasurfaces.« less

Local Stability of AIDS Epidemic Model Through Treatment and Vertical Transmission with Time Delay

NASA Astrophysics Data System (ADS)

Novi W, Cascarilla; Lestari, Dwi

2016-02-01

This study aims to explain stability of the spread of AIDS through treatment and vertical transmission model. Human with HIV need a time to positively suffer AIDS. The existence of a time, human with HIV until positively suffer AIDS can be delayed for a time so that the model acquired is the model with time delay. The model form is a nonlinear differential equation with time delay, SIPTA (susceptible-infected-pre AIDS-treatment-AIDS). Based on SIPTA model analysis results the disease free equilibrium point and the endemic equilibrium point. The disease free equilibrium point with and without time delay are local asymptotically stable if the basic reproduction number is less than one. The endemic equilibrium point will be local asymptotically stable if the time delay is less than the critical value of delay, unstable if the time delay is more than the critical value of delay, and bifurcation occurs if the time delay is equal to the critical value of delay.

Delayed Matching to Sample: Probability of Responding in Accord with Equivalence as a Function of Different Delays

ERIC Educational Resources Information Center

Arntzen, Erik

2006-01-01

The present series of 4 experiments investigated the probability of responding in accord with equivalence in adult human participants as a function of increasing or decreasing delays in a many-to-one (MTO) or comparison-as-node and one-to-many (OTM) or sample-as-node conditional discrimination procedure. In Experiment 1, 12 participants started…

Delay to Reconstruction of the Adolescent Anterior Cruciate Ligament: The Socioeconomic Impact on Treatment.

PubMed

Newman, Justin T; Carry, Patrick M; Terhune, Elizabeth B; Spruiell, Murray; Heare, Austin; Mayo, Meredith; Vidal, Armando F

2014-08-01

A delay in pediatric and adolescent anterior cruciate ligament (ACL) reconstruction is associated with an increase in the number of concomitant meniscal and chondral injuries. Factors that contribute to this delay have not been well described. Socioeconomic and demographic factors are related to ACL surgery timing. Cohort study; Level of evidence, 3. All subjects who underwent primary ACL reconstruction at a single tertiary pediatric hospital between 2005 and 2012 were retrospectively reviewed. Variables included concomitant knee injuries (cartilage or meniscus injuries requiring additional operative treatment) and chronologic, demographic, and socioeconomic factors. Multivariable Cox proportional-hazards analyses were used to identify factors related to ACL surgery timing. The mean age of the 272 subjects was 15.2 ± 2.12 years. Time to surgery was significantly different among subjects who required multiple additional surgical procedures at time of ACL reconstruction (median, 3.3 months) compared with subjects with 1 (median, 2.0 months) or no additional injuries (median, 1.6 months). Subjects underwent ACL reconstruction significantly sooner if they were older at the time of injury (hazard ratio [HR], 1.2 per 1 year; 95% CI, 1.1-1.2; P < .0001) or were covered by a commercial insurance plan (HR, 2.0; 95% CI, 1.6-2.6; P < .0001). Median time to ACL surgery was 1.5 months (95% CI, 1.3-1.7) for subjects with commercial insurance plans compared with 3.0 months (95% CI, 2.3-3.3) for subjects with noncommercial insurance coverage. The risk of delayed ACL surgery was significantly higher among pediatric and adolescent subjects who were less affluent, who were covered by a noncommercial insurance plan, and who were younger. This study also confirms previous studies that have reported an association between a delay in ACL surgery and the presence of additional knee injuries requiring operative treatment, accentuating the importance of timely care. Access to care is a current area of research interest and health policy formation. Information in this arena drives 2 important aspects of health: most immediately, care provided to patients, and over a broader scope, the policy that directs health care. The orthopaedic surgeon should be aware of the association between socioeconomic and demographic factors and ACL surgery timing to optimize outcomes.

Controller Synthesis for Periodically Forced Chaotic Systems

NASA Astrophysics Data System (ADS)

Basso, Michele; Genesio, Roberto; Giovanardi, Lorenzo

Delayed feedback controllers are an appealing tool for stabilization of periodic orbits in chaotic systems. Despite their conceptual simplicity, specific and reliable design procedures are difficult to obtain, partly also because of their inherent infinite-dimensional structure. This chapter considers the use of finite dimensional linear time invariant controllers for stabilization of periodic solutions in a general class of sinusoidally forced nonlinear systems. For such controllers — which can be interpreted as rational approximations of the delayed ones — we provide a computationally attractive synthesis technique based on Linear Matrix Inequalities (LMIs), by mixing results concerning absolute stability of nonlinear systems and robustness of uncertain linear systems. The resulting controllers prove to be effective for chaos suppression in electronic circuits and systems, as shown by two different application examples.

Do as I … Did! Long-term memory of imitative actions in dogs (Canis familiaris).

PubMed

Fugazza, Claudia; Pogány, Ákos; Miklósi, Ádám

2016-03-01

This study demonstrates long-term declarative memory of imitative actions in a non-human animal species. We tested 12 pet dogs for their ability to imitate human actions after retention intervals ranging from 1 to 24 h. For comparison, another 12 dogs were tested for the same actions without delay between demonstration and recall. Our test consisted of a modified version of the Do as I Do paradigm, combined with the two-action procedure to control for non-imitative processes. Imitative performance of dogs remained consistently high independent of increasing retention intervals, supporting the idea that dogs are able to retain mental representations of human actions for an extended period of time. The ability to imitate after such delays supports the use of long-term declarative memory.

The effects of the framing of time on delay discounting.

PubMed

DeHart, William Brady; Odum, Amy L

2015-01-01

We examined the effects of the framing of time on delay discounting. Delay discounting is the process by which delayed outcomes are devalued as a function of time. Time in a titrating delay discounting task is often framed in calendar units (e.g., as 1 week, 1 month, etc.). When time is framed as a specific date, delayed outcomes are discounted less compared to the calendar format. Other forms of framing time; however, have not been explored. All participants completed a titrating calendar unit delay-discounting task for money. Participants were also assigned to one of two delay discounting tasks: time as dates (e.g., June 1st, 2015) or time in units of days (e.g., 5000 days), using the same delay distribution as the calendar delay-discounting task. Time framed as dates resulted in less discounting compared to the calendar method, whereas time framed as days resulted in greater discounting compared to the calendar method. The hyperboloid model fit best compared to the hyperbola and exponential models. How time is framed may alter how participants attend to the delays as well as how the delayed outcome is valued. Altering how time is framed may serve to improve adherence to goals with delayed outcomes. © Society for the Experimental Analysis of Behavior.

Myoelectric stimulation on peroneal muscles resists simulated ankle sprain motion.

PubMed

Fong, Daniel Tik-Pui; Chu, Vikki Wing-Shan; Chan, Kai-Ming

2012-07-26

The inadequate reaction time of the peroneal muscles in response to an incorrect foot contact event has been proposed as one of the etiological factors contributing to ankle joint inversion injury. Thus, the current study aimed to investigate the efficacy of a myoelectric stimulation applied to the peroneal muscles in the prevention of a simulated ankle inversion trauma. Ten healthy male subjects performed simulated inversion and supination tests on a pair of mechanical sprain simulators. An electrical signal was delivered to the peroneal muscles of the subjects through a pair of electrode pads. The start of the stimulus was synchronized with the drop of the sprain simulator's platform. In order to determine the maximum delay time which the stimulus could still resist the simulated ankle sprain motion, different delay time were test (0, 5, 10, and 15ms). Together with the control trial (no stimulus), there were 5 testing conditions for both simulated inversion and supination test. The effect was quantified by the drop in maximum ankle tilting angle and angular velocity, as determined by a motion analysis system with a standard laboratory procedure. Results showed that the myoelectric stimulation was effective in all conditions except the one with myoelectric stimulus delayed for 15ms in simulated supination test. It is concluded that myoelectric stimulation on peroneal muscles could resist an ankle spraining motion. Copyright © 2012 Elsevier Ltd. All rights reserved.

Outcome of 122 delayed breast reconstruction following post-mastectomy radiotherapy: The scarless latissimus dorsi flap with tissue expansion technique.

PubMed

de Runz, A; Boccara, D; Bekara, F; Chaouat, M; Mimoun, M

2017-02-01

Delayed breast reconstruction with tissue expansion may be risky after radiotherapy, due to the poor skin quality. To permit the use of the tissue expansion procedure, we propose a scarless latissimus dorsi flap to bring tissue trophicity, by a healthy vascularized muscular interface with no donor scar and no patch effect. The objective of this study is to assess the outcome of the tissue expansion technique with scarless latissimus dorsi flap after post-mastectomy radiotherapy. All the patients who had benefited of a delayed breast reconstruction after radiotherapy using tissue expansion technique with scarless latissimus dorsi flap, between January 2000 and January 2013, were reviewed. The exclusion criteria were: prior breast reconstruction, or interruption of breast reconstruction procedure due to active metastatic disease requiring ongoing oncological treatment. The complications were identified: failures of reconstruction, implant exposure, wound dehiscence, capsular contracture, deflation of implant, hematoma, infection, and skin necrosis. One hundred and twenty-two breasts were reviewed. The average time between the flap and the expander intervention was: 194±114 SD (28-1051) days. The mean volume of inserted expander was 633±111 SD (350-1100) mL and the mean inflation volume was 578±190 SD (170-1160) mL. The average time between insertion of the expander and insertion of the permanent implant was 132±76 SD (49-683) days. The mean inflation of the implant volume was 368±105 SD (130-620) mL. Forty patients developed at least one complication. The most common complication was the appearance of a capsular contracture requiring a capsulectomy: 11 (9.2%) with permanent implants and 6 (4.9%) with expander. Deflation of implants occurred with six permanent implants and with one expander. There were 3 breast reconstructions failures (two infections and one exposure of implants). This procedure offers the advantages that there is no unattractive scar, and that there are low rates of exposure or failed reconstruction. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Ergonomics perspective for identifying and reducing internal operative flow disruption for laparoscopic urological surgery.

PubMed

Al-Hakim, Latif; Xiao, Jiaquan; Sengupta, Shomik

2017-12-01

The aim of this study is to examine operative flow disruption that occurs inside the surgical field, (internal operative flow disruption (OFD)), during urological laparoscopies, and to relate those events to external ergonomics environment in terms of monitor location, level of instruments' handles, and location of surgical team members. According to the our best knowledge, this is the first study of its kind. A combination of real and video-aided observational study was conducted in the operating rooms at hospitals in Australia and China. Brain storming sessions were first conducted to identify the main internal OFD events, and the observable reasons, potential external, and latent ergonomic factors were listed. A prospective observational study was then conducted. The observer's records and the related video records of internal surgical fields were analysed. Procedures were categorised into groups based on similarity in ergonomics environment. The mapping process revealed 39 types of internal OFD events resulted from six reasons. A total of 24 procedures were selected and arranged into two groups, each with twelve procedures. Group A was carried out under satisfactory ergonomics environment, while Group B was conducted under unsatisfactory ergonomics environment. A total of 1178 OFD events were detected delaying the total observed operative times (2966 min) by 220 min (7.43%). Average OFD/h in group A was less than 15, while in group B about 29 OFD/h. There are two main latent ergonomics factors affecting the surgeon's performance; non-physiological posture and long-period static posture. The delays and number of internal OFD were nearly doubled where procedures were conducted under unsatisfactory external ergonomics environment. Some events such as stopping operation and irrelevant conversations during long procedures may have a positive influence on the surgeon's performance.

Acquisition of peak responding: what is learned?

PubMed

Balci, Fuat; Gallistel, Charles R; Allen, Brian D; Frank, Krystal M; Gibson, Jacqueline M; Brunner, Daniela

2009-01-01

We investigated how the common measures of timing performance behaved in the course of training on the peak procedure in C3H mice. Following fixed interval (FI) pre-training, mice received 16 days of training in the peak procedure. The peak time and spread were derived from the average response rates while the start and stop times and their relative variability were derived from a single-trial analysis. Temporal precision (response spread) appeared to improve in the course of training. This apparent improvement in precision was, however, an averaging artifact; it was mediated by the staggered appearance of timed stops, rather than by the delayed occurrence of start times. Trial-by-trial analysis of the stop times for individual subjects revealed that stops appeared abruptly after three to five sessions and their timing did not change as training was prolonged. Start times and the precision of start and stop times were generally stable throughout training. Our results show that subjects do not gradually learn to time their start or stop of responding. Instead, they learn the duration of the FI, with robust temporal control over the start of the response; the control over the stop of response appears abruptly later.

Acquisition of peak responding: What is learned?

PubMed Central

Balci, Fuat; Gallistel, Charles R.; Allen, Brian D.; Frank, Krystal M.; Gibson, Jacqueline M.; Brunner, Daniela

2009-01-01

We investigated how the common measures of timing performance behaved in the course of training on the peak procedure in C3H mice. Following fixed interval (FI) pre-training, mice received 16 days of training in the peak procedure. The peak time and spread were derived from the average response rates while the start and stop times and their relative variability were derived from a single-trial analysis. Temporal precision (response spread) appeared to improve in the course of training. This apparent improvement in precision was, however, an averaging artifact; it was mediated by the staggered appearance of timed stops, rather than by the delayed occurrence of start times. Trial-by-trial analysis of the stop times for individual subjects revealed that stops appeared abruptly after three to five sessions and their timing did not change as training was prolonged. Start times and the precision of start and stop times were generally stable throughout training. Our results show that subjects do not gradually learn to time their start or stop of responding. Instead, they learn the duration of the FI, with robust temporal control over the start of the response; the control over the stop of response appears abruptly later. PMID:18950695

Management of giant omphaloceles: A systematic review of methods of staged surgical vs. nonoperative delayed closure.

PubMed

Bauman, Brent; Stephens, Daniel; Gershone, Hannah; Bongiorno, Connie; Osterholm, Erin; Acton, Robert; Hess, Donavon; Saltzman, Daniel; Segura, Bradley

2016-10-01

Despite the numerous methods of closure for giant omphaloceles, uncertainty persists regarding the most effective option. Our purpose was to review the literature to clarify the current methods being used and to determine superiority of either staged surgical procedures or nonoperative delayed closure in order to recommend a standard of care for the management of the giant omphalocele. Our initial database search resulted in 378 articles. After de-duplification and review, we requested 32 articles relevant to our topic that partially met our inclusion criteria. We found that 14 articles met our criteria; these 14 studies were included in our analysis. 10 studies met the inclusion criteria for nonoperative delayed closure, and 4 studies met the inclusion criteria for staged surgical management. Numerous methods for managing giant omphaloceles have been described. Many studies use topical therapy secondarily to failed surgical management. Primary nonoperative delayed management had a cumulative mortality of 21.8% vs. 23.4% in the staged surgical group. Time to initiation of full enteric feedings was lower in the nonoperative delayed group at 14.6days vs 23.5days. Despite advances in medical and surgical therapies, giant omphaloceles are still associated with a high mortality rate and numerous morbidities. In our analysis, we found that nonoperative delayed management with silver therapy was associated with lower mortality and shorter duration to full enteric feeding. We recommend that nonoperative delayed management be utilized as the primary therapy for the newborn with a giant omphalocele. Copyright © 2016. Published by Elsevier Inc.

Current methods of diagnosis and management of ureteral injuries.

PubMed

Armenakas, N A

1999-04-01

A delay in diagnosis is the most important contributory factor in morbidity related to ureteral injury. The difficulty in making the diagnosis can be minimized by maintenance of a high index of suspicion and the timely performance of the appropriate radiographic and intraoperative evaluations. A decision on the timing of repair of the ureteral injury is based on the patient's overall condition, promptness of injury recognition, and proper injury staging. Ideally, when identified promptly, ureteral injuries should be repaired immediately. However, once there has been a delay in diagnosis or in the case of an unstable patient, temporizing measures can be used for urinary diversion. With the availability of simple, minimally invasive techniques to manage urinary extravasation and the absence of any risk of ureteral hemorrhage, ureteral reconstruction can be safely deferred until an opportune time during the recovery period. Successful surgical management requires familiarity with the broad reconstructive armamentarium and meticulous attention to the specific details of each procedure. Through adherence to the diagnostic and therapeutic principles outlined, complications can be minimized and renal preservation can be maximized in patients sustaining ureteral injuries.

A prospective randomized comparison between pylorus- and subtotal stomach-preserving pancreatoduodenectomy on postoperative delayed gastric emptying occurrence and long-term nutritional status.

PubMed

Matsumoto, Ippei; Shinzeki, Makoto; Asari, Sadaki; Goto, Tadahiro; Shirakawa, Sachiyo; Ajiki, Tetsuo; Fukumoto, Takumi; Suzuki, Yasuyuki; Ku, Yonson

2014-06-01

Pylorus-preserving pancreatoduodenectomy (PPPD) has been associated with a high incidence of delayed gastric emptying (DGE). There are few studies comparing DGE associated with PPPD and subtotal stomach-preserving pancreatoduodenectomy (SSPPD). Moreover, differences between the procedures with respect to long-term results have not been reported. A prospective randomized study was conducted to compare perioperative complications and long-term nutritional status with PPPD and SSPPD. One hundred patients with periampullary lesions were randomized to receive either PPPD (n = 50) or SSPPD (n = 50). All patients were followed up for 3 years after surgery or to the time of recurrence to evaluate nutritional status for the study. The effects of the procedure, age, and malignancy on changes in nutritional indicators were estimated with linear mixed models. This study was registered at UMIN Clinical Trials Registry (UMIN 000012337). The incidence of DGE assessed by the International Study Group of Pancreatic Surgery was 20% with PPPD and 12% with SSPPD (P = 0.414). There were no significant differences between the two procedures on postoperative serum albumin levels, serum total cholesterol levels, and body mass index during the 3-year follow-up period. SSPPD is equally effective in DGE occurrence rate and long-term nutritional status comparing to PPPD. © 2014 Wiley Periodicals, Inc.

Fusing human and machine skills for remote robotic operations

NASA Technical Reports Server (NTRS)

Schenker, Paul S.; Kim, Won S.; Venema, Steven C.; Bejczy, Antal K.

1991-01-01

The question of how computer assists can improve teleoperator trajectory tracking during both free and force-constrained motions is addressed. Computer graphics techniques which enable the human operator to both visualize and predict detailed 3D trajectories in real-time are reported. Man-machine interactive control procedures for better management of manipulator contact forces and positioning are also described. It is found that collectively, these novel advanced teleoperations techniques both enhance system performance and significantly reduce control problems long associated with teleoperations under time delay. Ongoing robotic simulations of the 1984 space shuttle Solar Maximum EVA Repair Mission are briefly described.

Where Have I Been? Where Should I Go? Spatial Working Memory on a Radial Arm Maze in a Rat Model of Depression

PubMed Central

Richter, Sophie Helene; Zeuch, Benjamin; Lankisch, Katja; Gass, Peter; Durstewitz, Daniel; Vollmayr, Barbara

2013-01-01

Disturbances in cognitive functioning are among the most debilitating problems experienced by patients with major depression. Investigations of these deficits in animals help to extend and refine our understanding of human emotional disorder, while at the same time providing valid tools to study higher executive functions in animals. We employ the “learned helplessness” genetic rat model of depression in studying working memory using an eight arm radial maze procedure with temporal delay. This so-called delayed spatial win-shift task consists of three phases, training, delay and test, requiring rats to hold information on-line across a retention interval and making choices based on this information in the test phase. According to a 2×2 factorial design, working memory performance of thirty-one congenitally helpless (cLH) and non-helpless (cNLH) rats was tested on eighteen trials, additionally imposing two different delay durations, 30 s and 15 min, respectively. While not observing a general cognitive deficit in cLH rats, the delay length greatly influenced maze performance. Notably, performance was most impaired in cLH rats tested with the shorter 30 s delay, suggesting a stress-related disruption of attentional processes in rats that are more sensitive to stress. Our study provides direct animal homologues of clinically important measures in human research, and contributes to the non-invasive assessment of cognitive deficits associated with depression. PMID:23614050

Token reinforcement, choice, and self-control in pigeons.

PubMed Central

Jackson, K; Hackenberg, T D

1996-01-01

Pigeons were exposed to self-control procedures that involved illumination of light-emitting diodes (LEDs) as a form of token reinforcement. In a discrete-trials arrangement, subjects chose between one and three LEDs; each LED was exchangeable for 2-s access to food during distinct posttrial exchange periods. In Experiment 1, subjects generally preferred the immediate presentation of a single LED over the delayed presentation of three LEDs, but differences in the delay to the exchange period between the two options prevented a clear assessment of the relative influence of LED delay and exchange-period delay as determinants of choice. In Experiment 2, in which delays to the exchange period from either alternative were equal in most conditions, all subjects preferred the delayed three LEDs more often than in Experiment-1. In Experiment 3, subjects preferred the option that resulted in a greater amount of food more often if the choices also produced LEDs than if they did not. In Experiment 4, preference for the delayed three LEDs was obtained when delays to the exchange period were equal, but reversed in favor of an immediate single LED when the latter choice also resulted in quicker access to exchange periods. The overall pattern of results suggests that (a) delay to the exchange period is a more critical determinant of choice than is delay to token presentation; (b) tokens may function as conditioned reinforcers, although their discriminative properties may be responsible for the self-control that occurs under token reinforcer arrangements; and (c) previously reported differences in the self-control choices of humans and pigeons may have resulted at least in part from the procedural conventions of using token reinforcers with human subjects and food reinforcers with pigeon subjects. PMID:8755699

Delayed hysteroscopic resection of retained tissues and uterine conservation after conservative treatment for placenta accreta.

PubMed

Hequet, Delphine; Morel, Olivier; Soyer, Philippe; Gayat, Etienne; Malartic, Cécile; Barranger, Emmanuel

2013-12-01

Conservative management of both the uterus and the abnormal placenta, which is left inside the uterus at the time of delivery, is one option of placenta accreta management. Complete elimination of the residual placenta is the main challenge of this procedure. To report the role, efficacy and safety of hysteroscopic resection in women presenting with severe pelvic pain and chronic intra-uterine retention after conservative treatment of placenta accreta. Four consecutive women who were treated with hysteroscopic resection of retained tissues after conservative treatment of placenta accreta or percreta at the time of delivery. Clinical files and surgical procedures were reviewed. All procedures were performed because of chronic pelvic pain and the absence of a complete spontaneous placental elimination. All procedures were successful and uneventful. The uterus was conserved with a complete disappearance of the symptoms in the four women, and two of them became pregnant. Hysteroscopic resection seems effective and safe for shortening the duration of placental elimination after conservative treatment in women with severe pelvic pain due to uterine retention. This approach allows conserving the uterus and future fertility. © 2013 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Ethanol induces impulsive-like responding in a delay-of-reward operant choice procedure: impulsivity predicts autoshaping.

PubMed

Tomie, A; Aguado, A S; Pohorecky, L A; Benjamin, D

1998-10-01

Autoshaping conditioned responses (CRs) are reflexive and targeted motor responses expressed as a result of experience with reward. To evaluate the hypothesis that autoshaping may be a form of impulsive responding, within-subjects correlations between performance on autoshaping and impulsivity tasks were assessed in 15 Long-Evans hooded rats. Autoshaping procedures [insertion of retractable lever conditioned stimulus (CS) followed by the response-independent delivery of food (US)] were followed by testing for impulsive-like responding in a two-choice lever-press operant delay-of-reward procedure (immediate small food reward versus delayed large food reward). Delay-of-reward functions revealed two distinct subject populations. Subjects in the Sensitive group (n=7) were more impulsive-like, increasing immediate reward choices at longer delays for large reward, while those in the Insensitive group (n=8) responded predominantly on only one lever. During the prior autoshaping phase, the Sensitive group had performed more autoshaping CRs, and correlations revealed that impulsive subjects acquired the autoshaping CR in fewer trials. In the Sensitive group, acute injections of ethanol (0, 0.25, 0.50, 1.00, 1.50 g/kg) given immediately before delay-of-reward sessions yielded an inverted U-shaped dose-response curve with increased impulsivity induced by the 0.25, 0.50, and 1.00 g/kg doses of ethanol, while choice strategy of the Insensitive group was not influenced by ethanol dose. Ethanol induced impulsive-like responding only in rats that were flexible in their response strategy (Sensitive group), and this group also performed more autoshaping CRs. Data support the hypothesis that autoshaping and impulsivity are linked.

Dynamics of scroll waves with time-delay propagation in excitable media

NASA Astrophysics Data System (ADS)

Chen, Jiang-Xing; Xiao, Jie; Qiao, Li-Yan; Xu, Jiang-Rong

2018-06-01

Information transmission delay can be widely observed in various systems. Here, we study the dynamics of scroll waves with time-delay propagation among slices in excitable media. Weak time delay induces scroll waves to meander. Through increasing the time delay, we find a series of dynamical transitions. Firstly, the straight filament of a scroll wave becomes twisted. Then, the scroll wave breaks and forms interesting patterns. With long time delay, loosed scroll waves are maintained while their period are greatly decreased. Also, cylinder waves appears. The influences of diffusively coupling strength on the time-delay-induced scroll waves are studied. It is found that the critical time delay characterizing those transitions decreases as the coupling strength is increased. A phase diagram in the diffusive coupling-time delay plane is presented.

Delayed Infective Endocarditis with Mycotic Aneurysm Rupture below the Mechanical Valved Conduit after the Bentall Procedure.

PubMed

Chen, Mei-Ling; Chen, Michael Y; Yin, Wei-Hsian; Wei, Jeng; Wang, Ji-Hung

2014-07-01

The Bentall procedure is the gold standard for treating aortic dissection complicated with valvular and ascending aorta disease. Recent results for this procedure have been excellent; nearly 100% of patients remain free of infective endocarditis in long-term follow-up. We report a case of delayed Streptococcus agalactiae infective endocarditis complicated by mycotic aneurysm in a man who had undergone the Bentall procedure with a mechanical valve conduit 15 years previously. The mycotic aneurysm was located in the remnant aortic root, below the mechanical valve conduit, and later ruptured into the right atrium. The patient was treated conservatively and survived the acute period. Later, the aortic root defect was repaired successfully by means of a hybrid technique using a Amplatzer duct occluder. Amplatzer duct occluder; Aortic dissection; Bentall technique; Infective endocarditis; Mycotic aneurysm.

An improved robust buffer allocation method for the project scheduling problem

NASA Astrophysics Data System (ADS)

Ghoddousi, Parviz; Ansari, Ramin; Makui, Ahmad

2017-04-01

Unpredictable uncertainties cause delays and additional costs for projects. Often, when using traditional approaches, the optimizing procedure of the baseline project plan fails and leads to delays. In this study, a two-stage multi-objective buffer allocation approach is applied for robust project scheduling. In the first stage, some decisions are made on buffer sizes and allocation to the project activities. A set of Pareto-optimal robust schedules is designed using the meta-heuristic non-dominated sorting genetic algorithm (NSGA-II) based on the decisions made in the buffer allocation step. In the second stage, the Pareto solutions are evaluated in terms of the deviation from the initial start time and due dates. The proposed approach was implemented on a real dam construction project. The outcomes indicated that the obtained buffered schedule reduces the cost of disruptions by 17.7% compared with the baseline plan, with an increase of about 0.3% in the project completion time.

49 CFR 236.563 - Delay time.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time. ...

49 CFR 236.563 - Delay time.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time. ...

Self-report surveys of student sleep and well-being: a review of use in the context of school start times.

PubMed

Ziporyn, Terra D; Malow, Beth A; Oakes, Kari; Wahlstrom, Kyla L

2017-12-01

A large body of literature supports the need to delay high school starting times to improve student health and well-being by allowing students an opportunity to get sufficient and appropriately timed sleep. However, a dearth of uniform and standardized tools has hampered efforts to collect data on adolescent sleep and related health behaviors that might be used to establish a need for, or to evaluate outcomes of, bell time delays. To assess validated tools available to schools and contrast them with tools that schools have actually used, we identified and reviewed published, validated self-report surveys of adolescent sleep and well-being, as well as unpublished surveys, used to assess student sleep and related health measures in US high schools considering later high school start times. Only three of the surveys reviewed had adequate psychometric properties and covered an appropriately wide range of health and academic questions to allow for discernment of outcomes in pre-post educational settings. The surveys exhibited marked variability in numerous areas, including focus, terminology, calculation of sleep duration, mode of administration, context of administration, and follow-up procedures. Our findings provide sleep researchers and school administrators with an overview of surveys that school districts have used, along with a deeper understanding of the challenges of choosing, designing, and administering self-report surveys in the context of changing school schedules. They also highlight the opportunities presented by these instruments to assess outcomes of delaying bell times, compare communities meaningfully, and establish the need for later school start times in individual school districts. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Initial experience with laparoscopic inferior epigastric vessel ligation for delayed transverse rectus abdominus musculocutaneous flap breast reconstruction.

PubMed

Trus, Thadeus L; Collins, E Dale; Demas, Christopher; Kerrigan, Carolyn

2007-04-01

Transverse rectus abdominus musculocutaneous (TRAM) flap breast reconstruction provides excellent cosmetic results. Pedicle flap viability is greatly enhanced by prereconstruction inferior epigastric vessel ligation, which encourages collateral arterial flow (delayed TRAM). We report our initial experience with laparoscopic inferior epigastric vessel ligation. Prospective case series. Tertiary academic center. Female patients with breast cancer who chose pedicle TRAM reconstruction. Vessel ligations were performed 7 to 14 days prior to reconstruction. Abdominal access was achieved with a 3-mm umbilical trocar. A 5-mm trocar was placed lateral to the rectus sheath in the right lower quadrant. Five-millimeter Teflon clips were used to ligate the vessels near their origin. Complications of surgery and subsequent flap viability. From January 2001 to July 2006, 130 patients had laparoscopic inferior epigastric vessel ligation, of whom 123 patients had bilateral ligation. Additional procedures in conjunction with vessel ligation were performed in 38 patients (sentinel node biopsy [27], bilateral oophorectomy [7], liver biopsy [2], breast biopsy [1], and Nissen fundoplication [1]). Median operative time for those patients undergoing ligation only was 32.6 minutes (range, 14-121 minutes). The inferior epigastric vessels were not identified in 2 patients. Metastatic breast cancer involving the liver was found in 1 patient. There were no conversions or complications. Subsequent TRAM flap viability was excellent in most cases, with 1 complete flap necrosis in a high-risk, morbidly obese patient. Laparoscopic inferior epigastric vessel ligation for delayed TRAM flap breast reconstruction is a safe, effective procedure.

Data forwarding mechanism for supporting real-time services during relocations in UMTS systems

NASA Astrophysics Data System (ADS)

Cai, Wei; Liao, Xianglong; Zheng, Liang; Liu, Zehong

2004-04-01

To minimize the interruption during the handovers or relocations invoked by subscribers moving is a very critical factor to enhance the performance of the UMTS systems. We know that the 2G systems have been optimized to minimize the interruption of speech during handovers by two main technologies: one is the bi-casting for the DL traffic and the other is the fast radio resynchronization by the UE for the UL traffic. In the UMTS systems, we have also implemented lossless relocations for non real-time services with high reliability by data buffering in the source RNC and target RNC for the UE. However, the UMTS systems support four QoS classes traffic flow: conversational class, streaming class, interactive class and background class. The main distinguishing factor between these QoS classes is how delay sensitive the traffic is: Conversational and Streaming classes are mainly used to carry real-time traffic flows, like video telephony, interactive and background classes are mainly used by traditional Internet applications like WWW, E-mail and FTP. It"s essential to provide the solutions for supporting real-time services to meet the requirement for QoS in UMTS systems. Apparently, the Data buffering mechanism is not adapted to real-time services because of it"s delay may exceed the basic requirement for real-time services. Under this background, the paper discussed two data forwarding solutions for real-time services from the PS domain in the UMTS systems: packet duplication and Core Network bi-casting. The former mechanism does not require any new procedures, messages nor information elements. The later mechanism requires that the GGSN or SGSN is able to bi-cast the DL traffic to the target RNC according to the relocations involving two SGSNs or just involving one SGSN. It also implicitly shows that we need change procedures at the nodes SGSN, GGSN and RNC which are involved in the relocation procedure based on existing procedures that we have already designed if adopt the later solution. In a detail way, the paper analyzed the characteristic for these two solutions respectively, concentrated on the packet flows and the message flows in those nodes involved in relocations. Additionally, also gave out the impact on present transport technologies in the wireless communication systems. However we shall minimize the impact of evolution of transport mechanism and utilize the resource efficiently according to the general requirements for QoS in UMTS systems.

The across frequency independence of equalization of interaural time delay in the equalization-cancellation model of binaural unmasking.

PubMed

Akeroyd, Michael A

2004-08-01

The equalization stage in the equalization-cancellation model of binaural unmasking compensates for the interaural time delay (ITD) of a masking noise by introducing an opposite, internal delay [N. I. Durlach, in Foundations of Modern Auditory Theory, Vol. II., edited by J. V. Tobias (Academic, New York, 1972)]. Culling and Summerfield [J. Acoust. Soc. Am. 98, 785-797 (1995)] developed a multi-channel version of this model in which equalization was "free" to use the optimal delay in each channel. Two experiments were conducted to test if equalization was indeed free or if it was "restricted" to the same delay in all channels. One experiment measured binaural detection thresholds, using an adaptive procedure, for 1-, 5-, or 17-component tones against a broadband masking noise, in three binaural configurations (N0S180, N180S0, and N90S270). The thresholds for the 1-component stimuli were used to normalize the levels of each of the 5- and 17-component stimuli so that they were equally detectable. If equalization was restricted, then, for the 5- and 17-component stimuli, the N90S270 and N180S0 configurations would yield a greater threshold than the N0S180 configurations. No such difference was found. A subsequent experiment measured binaural detection thresholds, via psychometric functions, for a 2-component complex tone in the same three binaural configurations. Again, no differential effect of configuration was observed. An analytic model of the detection of a complex tone showed that the results were more consistent with free equalization than restricted equalization, although the size of the differences was found to depend on the shape of the psychometric function for detection.

Validation of early image acquisitions following Tc-99 m sestamibi injection using a semiconductors camera of cadmium-zinc-telluride.

PubMed

Meyer, Celine; Weinmann, Pierre

2017-08-01

Cadmium-zinc-telluride (CZT) cameras allow to decrease significantly the acquisition time of myocardial perfusion imaging (MPI), but the duration of the examination is still long. Therefore, this study was performed to test the feasibility of early imaging following injection of Tc-99 m sestamibi using a CZT camera. Seventy patients underwent both an early and a delayed image acquisition after exercise stress test (n = 30), dipyridamole stress test (n = 20), and at rest (n = 20). After injection of Tc-99 m sestamibi, the early image acquisition started on average within 5 minutes for the exercise and rest groups, and 3 minutes 30 seconds for the dipyridamole group. Two independent observers evaluated image quality and extracardiac uptake on four-point scales. The difference between early and later images for each patient was scored on a five-point scale. The image quality and extracardiac uptake of early and delayed image acquisitions were not different for the three groups (P > .05). There was no significant difference between early and delayed image acquisitions in the exercise, dipyridamole, and rest groups, respectively, in 63%, 40%, and 80% of cases. In the exercise group and rest group, a defect was only present in early MPI, respectively, in 13% and 20% of cases. A defect was only present in delayed images in 10% of cases in the exercise group and in 45% of cases in the dipyridamole group. There was no difference between early and later image acquisitions in terms of quality. This protocol reduces the length of the procedure for the patient. Beginning with early image acquisitions may help to overcome the artifacts that are observed at the delayed time.

Impact of sentinel lymph node biopsy on immediate breast reconstruction after mastectomy.

PubMed

Wood, Benjamin C; David, Lisa R; Defranzo, Anthony J; Stewart, John H; Shen, Perry; Geisinger, Kim R; Marks, Malcolm W; Levine, Edward A

2009-07-01

Traditionally, sentinel lymph node biopsy (SLNB) is performed at the time of mastectomy and reconstruction. However, several groups have advocated SLNB as a separate outpatient procedure before mastectomy, when immediate reconstruction is planned, to allow for complete pathologic evaluation. The purpose of this study was to determine the impact of intraoperative analysis of SLNB on the reconstructive plan when performed at the same time as definitive surgery. A retrospective review was conducted of all mastectomy cases performed at a single institution between September 1998 and November 2007. Of the 747 mastectomy cases reviewed, SLNB was conducted in 344 cases, and there was immediate breast reconstruction in 193 of those cases. There were 27 (7.8%) false negative and three (0.9%) false positive intraoperative analysis of SLNB. Touch preparation analysis from the SLNB changed the reconstructive plan in four (2.1%) cases. In our experience, SLNB can be performed at the time of mastectomy with minimal impact on the reconstructive plan. A staged approach incurs significant additional expense, increases the delay in initiation of systemic therapy and the propensity of procedure-related morbidity; therefore, SLNB should not be performed as a separate procedure before definitive surgery with immediate breast reconstruction.

Wigner time delay in photodetachment of Tm-and in photoionization of Yb: A comparative study

NASA Astrophysics Data System (ADS)

Saha, Soumyajit; Jose, Jobin; Deshmukh, Pranawa; Dolmatov, Valeriy; Kheifets, Anatoli; Manson, Steven

2017-04-01

Preliminary studies of Wigner time delay in photodetachment spectra of negative ions have been reported. Photodetachment time delay for some dipole channels of Tm- and of Cl- were calculated using relativistic random phase approximation (RRPA). Comparisons between photodetachment time delay of Cl- and photoionization time delay of Ar were made. We investigate the photodetachment time delay for all three relativistically split nd -> ɛ f channels of Tm- and for nd -> ɛ f channels of Yb (isoelectronic to Tm-) using RRPA. We study the effect of the shape resonance, brought about by the centrifugal barrier potential, on photodetachment time delay. A negative ion is a good laboratory for studying the effects of shape resonances on time delay since the phase is unaffected by the Coulomb component. Wigner time delay in photodetachment of Tm- and in photoionization of Yb: A comparative study.

Evaluations of Three Methods for Remote Training

NASA Technical Reports Server (NTRS)

Woolford, B.; Chmielewski, C.; Pandya, A.; Adolf, J.; Whitmore, M.; Berman, A.; Maida, J.

1999-01-01

Long duration space missions require a change in training methods and technologies. For Shuttle missions, crew members could train for all the planned procedures, and carry documentation of planned procedures for a variety of contingencies. As International Space Station (ISS) missions of three months or longer are carried out, many more tasks will need to be performed for which little or no training was received prior to launch. Eventually, exploration missions will last several years, and communications with Earth will have long time delays or be impossible at times. This series of three studies was performed to identify the advantages and disadvantages of three types of training for self-instruction: video-conferencing; multimedia; and virtual reality. These studies each compared two types of training methods, on two different types of tasks. In two of the studies, the subject's were in an isolated, confined environment analogous to space flight; the third study was performed in a laboratory.

Probabilistic Nowcasting of Low-Visibility Procedure States at Vienna International Airport During Cold Season

NASA Astrophysics Data System (ADS)

Kneringer, Philipp; Dietz, Sebastian J.; Mayr, Georg J.; Zeileis, Achim

2018-04-01

Airport operations are sensitive to visibility conditions. Low-visibility events may lead to capacity reduction, delays and economic losses. Different levels of low-visibility procedures (lvp) are enacted to ensure aviation safety. A nowcast of the probabilities for each of the lvp categories helps decision makers to optimally schedule their operations. An ordered logistic regression (OLR) model is used to forecast these probabilities directly. It is applied to cold season forecasts at Vienna International Airport for lead times of 30-min out to 2 h. Model inputs are standard meteorological measurements. The skill of the forecasts is accessed by the ranked probability score. OLR outperforms persistence, which is a strong contender at the shortest lead times. The ranked probability score of the OLR is even better than the one of nowcasts from human forecasters. The OLR-based nowcasting system is computationally fast and can be updated instantaneously when new data become available.

A temporal discriminability account of children's eyewitness suggestibility.

PubMed

Bright-Paul, Alexandra; Jarrold, Christopher

2009-07-01

Children's suggestibility is typically measured using a three-stage 'event-misinformation-test' procedure. We examined whether suggestibility is influenced by the time delays imposed between these stages, and in particular whether the temporal discriminability of sources (event and misinformation) predicts performance. In a novel approach, the degree of source discriminability was calculated as the relative magnitude of two intervals (the ratio of event-misinformation and misinformation-test intervals), based on an adaptation of existing 'ratio-rule' accounts of memory. Five-year-olds (n =150) watched an event, and were exposed to misinformation, before memory for source was tested. The absolute event-test delay (12 versus 24 days) and the 'ratio' of event-misinformation/misinformation-test intervals (11:1, 3:1, 1:1, 1:3 and 1:11) were manipulated across participants. The temporal discriminability of sources, measured by the ratio, was indeed a strong predictor of suggestibility. Most importantly, if the ratio was constant (e.g. 18/6 versus 9/3 days), performance was remarkably similar despite variations in absolute delay (e.g. 24 versus 12 days). This intriguing finding not only extends the ratio-rule of distinctiveness to misinformation paradigms, but also serves to illustrate a new empirical means of differentiating between explanations of suggestibility based on interference between sources and disintegration of source information over time.

Effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks.

PubMed

Sun, Xiaojuan; Perc, Matjaž; Kurths, Jürgen

2017-05-01

In this paper, we study effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks. Our focus is on the impact of two parameters, namely the time delay τ and the probability of partial time delay p delay , whereby the latter determines the probability with which a connection between two neurons is delayed. Our research reveals that partial time delays significantly affect phase synchronization in this system. In particular, partial time delays can either enhance or decrease phase synchronization and induce synchronization transitions with changes in the mean firing rate of neurons, as well as induce switching between synchronized neurons with period-1 firing to synchronized neurons with period-2 firing. Moreover, in comparison to a neuronal network where all connections are delayed, we show that small partial time delay probabilities have especially different influences on phase synchronization of neuronal networks.

Impact of Delayed Infusion Time in Umbilical Cord Blood Transplantation.

PubMed

Mitchell, Richard; Wagner, John E; Brunstein, Claudio; Cao, Qing; McKenna, David H; Verneris, Michael R

2017-05-01

In umbilical cord blood (UCB) transplantation, UCB units are typically thawed, washed, and infused into the patient as rapidly as possible. In some instances there is a delay in the time from the unit thaw and wash procedure to infusion into the patient. Therefore, we examined the effect of thaw duration time on engraftment outcomes in 567 patients undergoing UCB transplantation. With a range of 32 to 523 minutes, a prolonged thaw duration had no obvious effect on the incidence of neutrophil engraftment or time to recovery. This was true for recipients of single UCB transplantation (incidence: 97% versus 93%, P = .13; time to neutrophil recovery: 21 days versus 21 days, P = .32; and platelet recovery: 79% versus 78%, P = .48), and similar results were observed in double UCB transplantation (time to neutrophil engraftment: 20 days versus 19 days, P = .71). However, there was a trend toward better platelet recovery in recipients of double UCB transplants with prolonged thaw duration (HR, 1.28; P = .06). In conclusion, this study demonstrates prolonged thaw duration has no detrimental effect on engraftment after single or double UCB transplantation. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Delay-range-dependent chaos synchronization approach under varying time-lags and delayed nonlinear coupling.

PubMed

Zaheer, Muhammad Hamad; Rehan, Muhammad; Mustafa, Ghulam; Ashraf, Muhammad

2014-11-01

This paper proposes a novel state feedback delay-range-dependent control approach for chaos synchronization in coupled nonlinear time-delay systems. The coupling between two systems is esteemed to be nonlinear subject to time-lags. Time-varying nature of both the intrinsic and the coupling delays is incorporated to broad scope of the present study for a better-quality synchronization controller synthesis. Lyapunov-Krasovskii (LK) functional is employed to derive delay-range-dependent conditions that can be solved by means of the conventional linear matrix inequality (LMI)-tools. The resultant control approach for chaos synchronization of the master-slave time-delay systems considers non-zero lower bound of the intrinsic as well as the coupling time-delays. Further, the delay-dependent synchronization condition has been established as a special case of the proposed LK functional treatment. Furthermore, a delay-range-dependent condition, independent of the delay-rate, has been provided to address the situation when upper bound of the delay-derivative is unknown. A robust state feedback control methodology is formulated for synchronization of the time-delay chaotic networks against the L2 norm bounded perturbations by minimizing the L2 gain from the disturbance to the synchronization error. Numerical simulation results are provided for the time-delay chaotic networks to show effectiveness of the proposed delay-range-dependent chaos synchronization methodologies. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Downhole delay assembly for blasting with series delay

DOEpatents

Ricketts, Thomas E.

1982-01-01

A downhole delay assembly is provided which can be placed into a blasthole for initiation of explosive in the blasthole. The downhole delay assembly includes at least two detonating time delay devices in series in order to effect a time delay of longer than about 200 milliseconds in a round of explosions. The downhole delay assembly provides a protective housing to prevent detonation of explosive in the blasthole in response to the detonation of the first detonating time delay device. There is further provided a connection between the first and second time delay devices. The connection is responsive to the detonation of the first detonating time delay device and initiates the second detonating time delay device. A plurality of such downhole delay assemblies are placed downhole in unfragmented formation and are initiated simultaneously for providing a round of explosive expansions. The explosive expansions can be used to form an in situ oil shale retort containing a fragmented permeable mass of formation particles.

Integration of myocardial scar identified by preoperative delayed contrast-enhanced MRI into a high-resolution mapping system for planning and guidance of VT ablation procedures

NASA Astrophysics Data System (ADS)

Rettmann, M. E.; Suzuki, A.; Wang, S.; Pottinger, N.; Arter, J.; Netzer, A.; Parker, K.; Viker, K.; Packer, D. L.

2017-03-01

Myocardial scarring creates a substrate for reentrant circuits which can lead to ventricular tachycardia. In ventricular catheter ablation therapy, regions of myocardial scarring are targeted to interrupt arrhythmic electrical pathways. Low voltage regions are a surrogate for myocardial scar and are identified by generating an electro anatomic map at the start of the procedure. Recent efforts have focussed on integration of preoperative scar information generated from delayed contrast-enhanced MR imaging to augment intraprocedural information. In this work, we describe an initial feasibility study of integration of a preoperative MRI derived scar maps into a high-resolution mapping system to improve planning and guidance of VT ablation procedures.

Parenting Predictors of Delay Inhibition in Socioeconomically Disadvantaged Preschoolers

PubMed Central

Merz, Emily C.; Landry, Susan H.; Zucker, Tricia A.; Barnes, Marcia A.; Assel, Michael; Taylor, Heather B.; Lonigan, Christopher J.; Phillips, Beth M.; Clancy-Menchetti, Jeanine; Eisenberg, Nancy; Spinrad, Tracy L.; Valiente, Carlos; de Villiers, Jill; Consortium, the School Readiness Research

2016-01-01

This study examined longitudinal associations between specific parenting factors and delay inhibition in socioeconomically disadvantaged preschoolers. At Time 1, parents and 2- to 4-year-old children (mean age = 3.21 years; N = 247) participated in a videotaped parent-child free play session, and children completed delay inhibition tasks (gift delay-wrap, gift delay-bow, and snack delay tasks). Three months later, at Time 2, children completed the same set of tasks. Parental responsiveness was coded from the parent-child free play sessions, and parental directive language was coded from transcripts of a subset of 127 of these sessions. Structural equation modeling was used, and covariates included age, gender, language skills, parental education, and Time 1 delay inhibition. Results indicated that in separate models, Time 1 parental directive language was significantly negatively associated with Time 2 delay inhibition, and Time 1 parental responsiveness was significantly positively associated with Time 2 delay inhibition. When these parenting factors were entered simultaneously, Time 1 parental directive language significantly predicted Time 2 delay inhibition whereas Time 1 parental responsiveness was no longer significant. Findings suggest that parental language that modulates the amount of autonomy allotted the child may be an important predictor of early delay inhibition skills. PMID:27833461

A Delay Discounting Model of Psychotherapy Termination

ERIC Educational Resources Information Center

Swift, Joshua K.; Callahan, Jennifer L.

2009-01-01

Delay discounting (DD) procedures are emerging as an important new method for psychotherapy researchers. In this paper a framework for conceptualizing existing, seemingly discrepant, research findings on termination is introduced and new directions for research are described. To illustrate the value of a DD framework, the common psychotherapy…

Six sigma tools for a patient safety-oriented, quality-checklist driven radiation medicine department.

PubMed

Kapur, Ajay; Potters, Louis

2012-01-01

The purpose of this work was to develop and implement six sigma practices toward the enhancement of patient safety in an electronic, quality checklist-driven, multicenter, paperless radiation medicine department. A quality checklist process map (QPM), stratified into consultation through treatment-completion stages was incorporated into an oncology information systems platform. A cross-functional quality management team conducted quality-function-deployment and define-measure-analyze-improve-control (DMAIC) six sigma exercises with a focus on patient safety. QPM procedures were Pareto-sorted in order of decreasing patient safety risk with failure mode and effects analysis (FMEA). Quantitative metrics for a grouped set of highest risk procedures were established. These included procedural delays, associated standard deviations and six sigma Z scores. Baseline performance of the QPM was established over the previous year of usage. Data-driven analysis led to simplification, standardization, and refinement of the QPM with standard deviation, slip-day reduction, and Z-score enhancement goals. A no-fly policy (NFP) for patient safety was introduced at the improve-control DMAIC phase, with a process map interlock imposed on treatment initiation in the event of FMEA-identified high-risk tasks being delayed or not completed. The NFP was introduced in a pilot phase with specific stopping rules and the same metrics used for performance assessments. A custom root-cause analysis database was deployed to monitor patient safety events. Relative to the baseline period, average slip days and standard deviations for the risk-enhanced QPM procedures improved by over threefold factors in the NFP period. The Z scores improved by approximately 20%. A trend for proactive delays instead of reactive hard stops was observed with no adverse effects of the NFP. The number of computed potential no-fly delays per month dropped from 60 to 20 over a total of 520 cases. The fraction of computed potential no-fly cases that were delayed in NFP compliance rose from 28% to 45%. Proactive delays rose to 80% of all delayed cases. For potential no-fly cases, event reporting rose from 18% to 50%, while for actually delayed cases, event reporting rose from 65% to 100%. With complex technologies, resource-compromised staff, and pressures to hasten treatment initiation, the use of the six sigma driven process interlocks may mitigate potential patient safety risks as demonstrated in this study. Copyright © 2012 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

A Systematic Evaluation of Blood Serum and Plasma Pre-Analytics for Metabolomics Cohort Studies

PubMed Central

Jobard, Elodie; Trédan, Olivier; Postoly, Déborah; André, Fabrice; Martin, Anne-Laure; Elena-Herrmann, Bénédicte; Boyault, Sandrine

2016-01-01

The recent thriving development of biobanks and associated high-throughput phenotyping studies requires the elaboration of large-scale approaches for monitoring biological sample quality and compliance with standard protocols. We present a metabolomic investigation of human blood samples that delineates pitfalls and guidelines for the collection, storage and handling procedures for serum and plasma. A series of eight pre-processing technical parameters is systematically investigated along variable ranges commonly encountered across clinical studies. While metabolic fingerprints, as assessed by nuclear magnetic resonance, are not significantly affected by altered centrifugation parameters or delays between sample pre-processing (blood centrifugation) and storage, our metabolomic investigation highlights that both the delay and storage temperature between blood draw and centrifugation are the primary parameters impacting serum and plasma metabolic profiles. Storing the blood drawn at 4 °C is shown to be a reliable routine to confine variability associated with idle time prior to sample pre-processing. Based on their fine sensitivity to pre-analytical parameters and protocol variations, metabolic fingerprints could be exploited as valuable ways to determine compliance with standard procedures and quality assessment of blood samples within large multi-omic clinical and translational cohort studies. PMID:27929400

Review of prostatic surgical procedures at a predominantly black hospital: a 22-year study.

PubMed Central

Heshmat, M. Y.; Kovi, J.; Rao, M. S.; Mohla, S.; Spurlin, D. W.; Jean-Baptiste, G.

1992-01-01

This article reports the results of a pathoepidemiological study of a cohort of black men who had prostatic surgery at Howard University Hospital between 1968 and 1989. The median age of patients at diagnosis of prostate cancer increased by 8 years during the study period, indicating either a delay in seeking medical care or a true delay in onset of the disease. The trends of prevalence of biopsies with cancer in various age groups suggested a sharp rise in the incidence of prostate cancer after the age of 70. The significant increase in popularity of needle biopsy during the period 1982 to 1989 after a 7-year plateau is an indication of increased perceived value of this procedure with experience and technical improvement. The prevalence of biopsies with cancer in all successive time periods of the study showed a bimodal distribution with an early hump in the 50- to 54-year-old age group. This hump is analogous to the break in the rising incidence of breast cancer between the ages of 47 and 52 (Clemmesen hook). This similarity could be explained on the basis of hormonal dependence of the two cancers. PMID:1507257

Experimental determination of the correlation properties of plasma turbulence using 2D BES systems

NASA Astrophysics Data System (ADS)

Fox, M. F. J.; Field, A. R.; van Wyk, F.; Ghim, Y.-c.; Schekochihin, A. A.; the MAST Team

2017-04-01

A procedure is presented to map from the spatial correlation parameters of a turbulent density field (the radial and binormal correlation lengths and wavenumbers, and the fluctuation amplitude) to correlation parameters that would be measured by a beam emission spectroscopy (BES) diagnostic. The inverse mapping is also derived, which results in resolution criteria for recovering correct correlation parameters, depending on the spatial response of the instrument quantified in terms of point-spread functions (PSFs). Thus, a procedure is presented that allows for a systematic comparison between theoretical predictions and experimental observations. This procedure is illustrated using the Mega-Ampere Spherical Tokamak BES system and the validity of the underlying assumptions is tested on fluctuating density fields generated by direct numerical simulations using the gyrokinetic code GS2. The measurement of the correlation time, by means of the cross-correlation time-delay method, is also investigated and is shown to be sensitive to the fluctuating radial component of velocity, as well as to small variations in the spatial properties of the PSFs.

Changing delay discounting in the light of the competing neurobehavioral decision systems theory: a review.

PubMed

Koffarnus, Mikhail N; Jarmolowicz, David P; Mueller, E Terry; Bickel, Warren K

2013-01-01

Excessively devaluing delayed reinforcers co-occurs with a wide variety of clinical conditions such as drug dependence, obesity, and excessive gambling. If excessive delay discounting is a trans-disease process that underlies the choice behavior leading to these and other negative health conditions, efforts to change an individual's discount rate are arguably important. Although discount rate is often regarded as a relatively stable trait, descriptions of interventions and environmental manipulations that successfully alter discount rate have begun to appear in the literature. In this review, we compare published examples of procedures that change discount rate and classify them into categories of procedures, including therapeutic interventions, direct manipulation of the executive decision-making system, framing effects, physiological state effects, and acute drug effects. These changes in discount rate are interpreted from the perspective of the competing neurobehavioral decision systems theory, which describes a combination of neurological and behavioral processes that account for delay discounting. We also suggest future directions that researchers could take to identify the mechanistic processes that allow for changes in discount rate and to test whether the competing neurobehavioral decision systems view of delay discounting is correct. © Society for the Experimental Analysis of Behavior.

Changing Delay Discounting in the Light of the Competing Neurobehavioral Decision Systems Theory: a Review

PubMed Central

Koffarnus, Mikhail N.; Jarmolowicz, David P.; Mueller, E. Terry; Bickel, Warren K.

2014-01-01

Excessively devaluing delayed reinforcers co-occurs with a wide variety of clinical conditions such as drug dependence, obesity, and excessive gambling. If excessive delay discounting is a trans-disease process that underlies the choice behavior leading to these and other negative health conditions, efforts to change an individual’s discount rate are arguably important. Although discount rate is often regarded as a relatively stable trait, descriptions of interventions and environmental manipulations that successfully alter discount rate have begun to appear in the literature. In this review, we compare published examples of procedures that change discount rate and classify them into categories of procedures, including therapeutic interventions, direct manipulation of the executive decision-making system, framing effects, physiological state effects, and acute drug effects. These changes in discount rate are interpreted from the perspective of the competing neurobehavioral decision systems theory, which describes a combination of neurological and behavioral processes that account for delay discounting. We also suggest future directions that researchers could take to identify the mechanistic processes that allow for changes in discount rate and to test whether the competing neurobehavioral decision systems view of delay discounting is correct. PMID:23344987

The Aviation System Analysis Capability Airport Capacity and Delay Models

NASA Technical Reports Server (NTRS)

Lee, David A.; Nelson, Caroline; Shapiro, Gerald

1998-01-01

The ASAC Airport Capacity Model and the ASAC Airport Delay Model support analyses of technologies addressing airport capacity. NASA's Aviation System Analysis Capability (ASAC) Airport Capacity Model estimates the capacity of an airport as a function of weather, Federal Aviation Administration (FAA) procedures, traffic characteristics, and the level of technology available. Airport capacity is presented as a Pareto frontier of arrivals per hour versus departures per hour. The ASAC Airport Delay Model allows the user to estimate the minutes of arrival delay for an airport, given its (weather dependent) capacity. Historical weather observations and demand patterns are provided by ASAC as inputs to the delay model. The ASAC economic models can translate a reduction in delay minutes into benefit dollars.

Optimizing claims payment for successful risk management.

PubMed

Frates, Janice; Ginty, Mary Jo; Baker, Linda

2002-05-01

Disputed claims and delayed payments are among the principal sources of provider and vendor dissatisfaction with managed care payment systems. Timely and accurate claims-payment systems are essential to ensure provider and vendor satisfaction, fiscal stability, and regulatory compliance. A focused analysis of conditions contributing to late payment of claims can disclose problems in provider, vendor, or payer operational and billing procedures, contracting processes, information systems, or human resources management. Resolution of these conditions equips claims-processing staff with tools to resolve problem claims promptly, thereby lowering costs.

A computerized traffic control algorithm to determine optimal traffic signal settings. Ph.D. Thesis - Toledo Univ.

NASA Technical Reports Server (NTRS)

Seldner, K.

1977-01-01

An algorithm was developed to optimally control the traffic signals at each intersection using a discrete time traffic model applicable to heavy or peak traffic. Off line optimization procedures were applied to compute the cycle splits required to minimize the lengths of the vehicle queues and delay at each intersection. The method was applied to an extensive traffic network in Toledo, Ohio. Results obtained with the derived optimal settings are compared with the control settings presently in use.

Commissioning of an integrated platform for time-resolved treatment delivery in scanned ion beam therapy by means of optical motion monitoring.

PubMed

Fattori, G; Saito, N; Seregni, M; Kaderka, R; Pella, A; Constantinescu, A; Riboldi, M; Steidl, P; Cerveri, P; Bert, C; Durante, M; Baroni, G

2014-12-01

The integrated use of optical technologies for patient monitoring is addressed in the framework of time-resolved treatment delivery for scanned ion beam therapy. A software application has been designed to provide the therapy control system (TCS) with a continuous geometrical feedback by processing the external surrogates tridimensional data, detected in real-time via optical tracking. Conventional procedures for phase-based respiratory phase detection were implemented, as well as the interface to patient specific correlation models, in order to estimate internal tumor motion from surface markers. In this paper, particular attention is dedicated to the quantification of time delays resulting from system integration and its compensation by means of polynomial interpolation in the time domain. Dedicated tests to assess the separate delay contributions due to optical signal processing, digital data transfer to the TCS and passive beam energy modulation actuation have been performed. We report the system technological commissioning activities reporting dose distribution errors in a phantom study, where the treatment of a lung lesion was simulated, with both lateral and range beam position compensation. The zero-delay systems integration with a specific active scanning delivery machine was achieved by tuning the amount of time prediction applied to lateral (14.61 ± 0.98 ms) and depth (34.1 ± 6.29 ms) beam position correction signals, featuring sub-millimeter accuracy in forward estimation. Direct optical target observation and motion phase (MPh) based tumor motion discretization strategies were tested, resulting in 20.3(2.3)% and 21.2(9.3)% median (IQR) percentual relative dose difference with respect to static irradiation, respectively. Results confirm the technical feasibility of the implemented strategy towards 4D treatment delivery, with negligible percentual dose deviations with respect to static irradiation.

On reliable time-frequency characterization and delay estimation of stimulus frequency otoacoustic emissions

NASA Astrophysics Data System (ADS)

Biswal, Milan; Mishra, Srikanta

2018-05-01

The limited information on origin and nature of stimulus frequency otoacoustic emissions (SFOAEs) necessitates a thorough reexamination into SFOAE analysis procedures. This will lead to a better understanding of the generation of SFOAEs. The SFOAE response waveform in the time domain can be interpreted as a summation of amplitude modulated and frequency modulated component waveforms. The efficiency of a technique to segregate these components is critical to describe the nature of SFOAEs. Recent advancements in robust time-frequency analysis algorithms have staked claims on the more accurate extraction of these components, from composite signals buried in noise. However, their potential has not been fully explored for SFOAEs analysis. Indifference to distinct information, due to nature of these analysis techniques, may impact the scientific conclusions. This paper attempts to bridge this gap in literature by evaluating the performance of three linear time-frequency analysis algorithms: short-time Fourier transform (STFT), continuous Wavelet transform (CWT), S-transform (ST) and two nonlinear algorithms: Hilbert-Huang Transform (HHT), synchrosqueezed Wavelet transform (SWT). We revisit the extraction of constituent components and estimation of their magnitude and delay, by carefully evaluating the impact of variation in analysis parameters. The performance of HHT and SWT from the perspective of time-frequency filtering and delay estimation were found to be relatively less efficient for analyzing SFOAEs. The intrinsic mode functions of HHT does not completely characterize the reflection components and hence IMF based filtering alone, is not recommended for segregating principal emission from multiple reflection components. We found STFT, WT, and ST to be suitable for canceling multiple internal reflection components with marginal altering in SFOAE.

Empirical models for use in designing decompression procedures for space operations

NASA Technical Reports Server (NTRS)

Conkin, Johnny; Edwards, Benjamin F.; Waligora, James M.; Horrigan, David J., Jr.

1987-01-01

Empirical models for predicting the incidence of Type 1 altitude decompression sickness (DCS) and venous gas emboli (VGE) during space extravehicular activity (EVA), and for use in designing safe denitrogenation decompression procedures are developed. The models are parameterized using DCS and VGE incidence data from NASA and USAF manned altitude chamber decompression tests using 607 male and female subject tests. These models, and procedures for their use, consist of: (1) an exponential relaxation model and procedure for computing tissue nitrogen partial pressure resulting from a specified prebreathing and stepped decompression sequence; (2) a formula for calculating Tissue Ratio (TR), a tissue decompression stress index; (3) linear and Hill equation models for predicting the total incidence of VGE and DCS attendant with a particular TR; (4) graphs of cumulative DCS and VGE incidence (risk) versus EVA exposure time at any specified TR; and (5) two equations for calculating the average delay period for the initial detection of VGE or indication of Type 1 DCS in a group after a specific denitrogenation decompression procedure. Several examples of realistic EVA preparations are provided.

Time-delayed feedback control of diffusion in random walkers.

PubMed

Ando, Hiroyasu; Takehara, Kohta; Kobayashi, Miki U

2017-07-01

Time delay in general leads to instability in some systems, while specific feedback with delay can control fluctuated motion in nonlinear deterministic systems to a stable state. In this paper, we consider a stochastic process, i.e., a random walk, and observe its diffusion phenomenon with time-delayed feedback. As a result, the diffusion coefficient decreases with increasing delay time. We analytically illustrate this suppression of diffusion by using stochastic delay differential equations and justify the feasibility of this suppression by applying time-delayed feedback to a molecular dynamics model.

Fixed-interval performance and self-control in children.

PubMed Central

Darcheville, J C; Rivière, V; Wearden, J H

1992-01-01

Operant responses of 16 children (mean age 6 years and 1 month) were reinforced according to different fixed-interval schedules (with interreinforcer intervals of 20, 30, or 40 s) in which the reinforcers were either 20-s or 40-s presentations of a cartoon. In another procedure, they received training on a self-control paradigm in which both reinforcer delay (0.5 s or 40 s) and reinforcer duration (20 s or 40 s of cartoons) varied, and subjects were offered a choice between various combinations of delay and duration. Individual differences in behavior under the self-control procedure were precisely mirrored by individual differences under the fixed-interval schedule. Children who chose the smaller immediate reinforcer on the self-control procedure (impulsive) produced short postreinforcement pauses and high response rates in the fixed-interval conditions, and both measures changed little with changes in fixed-interval value. Conversely, children who chose the larger delayed reinforcer in the self-control condition (the self-controlled subjects) exhibited lower response rates and long postreinforcement pauses, which changed systematically with changes in the interval, in their fixed-interval performances. PMID:1573372

Beyond discounting: possible experimental models of impulse control.

PubMed

Monterosso, J; Ainslie, G

1999-10-01

Animal studies of impulsivity have typically used one of three models: a delay of reward procedure, a differential reinforcement for low rate responding (DRL) procedure, or an autoshaping procedure. In each of these paradigms, we argue, measurement of impulsivity is implicitly or explicitly equated with the effect delay has on the value of reward. The steepness by which delay diminishes value (the temporal discount function) is treated as an index of impulsivity. In order to provide a better analog of human impulsivity, this model needs to be expanded to include the converse of impulsivity - self-control. Through mechanisms such as committing to long range interests before the onset of temptation, or through bundling individual choices into classes of choices that are made at once, human decision-making can often look far less myopic than single trial experiments predict. For people, impulsive behavior may be more often the result of the breakdown of self-control mechanisms than of steep discount functions. Existing animal models of self-control are discussed, and future directions are suggested for psychopharmacological research.

Development of QC Procedures for Ocean Data Obtained by National Research Projects of Korea

NASA Astrophysics Data System (ADS)

Kim, S. D.; Park, H. M.

2017-12-01

To establish data management system for ocean data obtained by national research projects of Ministry of Oceans and Fisheries of Korea, KIOST conducted standardization and development of QC procedures. After reviewing and analyzing the existing international and domestic ocean-data standards and QC procedures, the draft version of standards and QC procedures were prepared. The proposed standards and QC procedures were reviewed and revised by experts in the field of oceanography and academic societies several times. A technical report on the standards of 25 data items and 12 QC procedures for physical, chemical, biological and geological data items. The QC procedure for temperature and salinity data was set up by referring the manuals published by GTSPP, ARGO and IOOS QARTOD. It consists of 16 QC tests applicable for vertical profile data and time series data obtained in real-time mode and delay mode. Three regional range tests to inspect annual, seasonal and monthly variations were included in the procedure. Three programs were developed to calculate and provide upper limit and lower limit of temperature and salinity at depth from 0 to 1550m. TS data of World Ocean Database, ARGO, GTSPP and in-house data of KIOST were analysed statistically to calculate regional limit of Northwest Pacific area. Based on statistical analysis, the programs calculate regional ranges using mean and standard deviation at 3 kind of grid systems (3° grid, 1° grid and 0.5° grid) and provide recommendation. The QC procedures for 12 data items were set up during 1st phase of national program for data management (2012-2015) and are being applied to national research projects practically at 2nd phase (2016-2019). The QC procedures will be revised by reviewing the result of QC application when the 2nd phase of data management programs is completed.

Buspirone Reduces Sexual Risk-Taking Intent but not Cocaine Self-Administration

PubMed Central

Bolin, B. Levi; Lile, Joshua A.; Marks, Katherine R.; Beckmann, Joshua S.; Rush, Craig R.; Stoops, William W.

2016-01-01

Impulsive sexual decision-making may underlie sexual risk-taking behavior that contributes to the disproportionately high prevalence of HIV infection among cocaine users. Delay-discounting procedures measure impulsive decision-making and may provide insight into the underlying mechanisms of sexual risk-taking behavior. The anxiolytic drug buspirone reduces delay discounting in rats and blunts the reinforcing effects of cocaine in some preclinical studies suggesting that it might have utility in the treatment of cocaine-use disorders. This study determined whether buspirone mitigates impulsive risky sexual decision-making in cocaine users on a sexual delay-discounting procedure. The effects of buspirone maintenance on the abuse-related and physiological effects of cocaine were also tested. Nine (N = 9) current cocaine users completed a repeated-measures, inpatient protocol in which sexual delay discounting was assessed following three days of maintenance on placebo and buspirone (30 mg/day) in counterbalanced order. The reinforcing, subject-rated, and physiological effects of placebo and intranasal cocaine (15 and 45 mg) were also assessed during buspirone and placebo maintenance. Buspirone increased the likelihood of condom use for hypothetical sexual partners that were categorized as most likely to have a sexually transmitted infection and least sexually desirable. Cocaine functioned as a reinforcer and increased positive subjective effects ratings, but buspirone maintenance did not impact these effects of cocaine. Buspirone was also safe and tolerable when combined with cocaine and may have blunted some its cardiovascular effects. The results from the sexual delay-discounting procedure indicate that buspirone may reduce preference for riskier sex in cocaine users. PMID:27254258

76 FR 80226 - Technical Amendments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-23

... final rule, effective upon publication. Generally, the Administrative Procedure Act (APA) requires a.... Additionally, the APA requires that a final rule must have a delayed effective date of 30 days from the date of... delayed effective date requirement under the APA. 5 U.S.C. 553(d)(3). Again the technical change conforms...

Teaching Self-Control to Small Groups of Dually Diagnosed Adults.

ERIC Educational Resources Information Center

Dixon, Mark R.; Holcomb, Sharon

2000-01-01

A study used a progressive delay procedure to teach self-control to six adults with mental retardation. At baseline, participants chose an immediate smaller reinforcer rather than a larger delayed reinforcer. Progressive increases in work requirements for gaining access to a larger reinforcer resulted in participants selecting larger delayed…

Effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks

NASA Astrophysics Data System (ADS)

Sun, Xiaojuan; Perc, Matjaž; Kurths, Jürgen

2017-05-01

In this paper, we study effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks. Our focus is on the impact of two parameters, namely the time delay τ and the probability of partial time delay pdelay, whereby the latter determines the probability with which a connection between two neurons is delayed. Our research reveals that partial time delays significantly affect phase synchronization in this system. In particular, partial time delays can either enhance or decrease phase synchronization and induce synchronization transitions with changes in the mean firing rate of neurons, as well as induce switching between synchronized neurons with period-1 firing to synchronized neurons with period-2 firing. Moreover, in comparison to a neuronal network where all connections are delayed, we show that small partial time delay probabilities have especially different influences on phase synchronization of neuronal networks.

Finite time synchronization of memristor-based Cohen-Grossberg neural networks with mixed delays.

PubMed

Chen, Chuan; Li, Lixiang; Peng, Haipeng; Yang, Yixian

2017-01-01

Finite time synchronization, which means synchronization can be achieved in a settling time, is desirable in some practical applications. However, most of the published results on finite time synchronization don't include delays or only include discrete delays. In view of the fact that distributed delays inevitably exist in neural networks, this paper aims to investigate the finite time synchronization of memristor-based Cohen-Grossberg neural networks (MCGNNs) with both discrete delay and distributed delay (mixed delays). By means of a simple feedback controller and novel finite time synchronization analysis methods, several new criteria are derived to ensure the finite time synchronization of MCGNNs with mixed delays. The obtained criteria are very concise and easy to verify. Numerical simulations are presented to demonstrate the effectiveness of our theoretical results.

Time-delayed chameleon: Analysis, synchronization and FPGA implementation

NASA Astrophysics Data System (ADS)

Rajagopal, Karthikeyan; Jafari, Sajad; Laarem, Guessas

2017-12-01

In this paper we report a time-delayed chameleon-like chaotic system which can belong to different families of chaotic attractors depending on the choices of parameters. Such a characteristic of self-excited and hidden chaotic flows in a simple 3D system with time delay has not been reported earlier. Dynamic analysis of the proposed time-delayed systems are analysed in time-delay space and parameter space. A novel adaptive modified functional projective lag synchronization algorithm is derived for synchronizing identical time-delayed chameleon systems with uncertain parameters. The proposed time-delayed systems and the synchronization algorithm with controllers and parameter estimates are then implemented in FPGA using hardware-software co-simulation and the results are presented.

Dual echelon femtosecond single-shot spectroscopy

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

Shin, Taeho; Wolfson, Johanna W.; Teitelbaum, Samuel W.

We have developed a femtosecond single-shot spectroscopic technique to measure irreversible changes in condensed phase materials in real time. Crossed echelons generate a two-dimensional array of time-delayed pulses with one femtosecond probe pulse. This yields 9 ps of time-resolved data from a single laser shot, filling a gap in currently employed measurement methods. We can now monitor ultrafast irreversible dynamics in solid-state materials or other samples that cannot be flowed or replenished between laser shots, circumventing limitations of conventional pump-probe methods due to sample damage or product buildup. Despite the absence of signal-averaging in the single-shot measurement, an acceptable signal-to-noisemore » level has been achieved via background and reference calibration procedures. Pump-induced changes in relative reflectivity as small as 0.2%−0.5% are demonstrated in semimetals, with both electronic and coherent phonon dynamics revealed by the data. The optical arrangement and the space-to-time conversion and calibration procedures necessary to achieve this level of operation are described. Sources of noise and approaches for dealing with them are discussed.« less

Achieving Bidirectional Long Delays In Pulmonary Vein Antral Lines Prior To Bidirectional Block In Patients With Paroxysmal Atrial Fibrillation (The Bi-Bi Technique For Atrial Fibrillation Ablation).

PubMed

Mina, Adel F; Warnecke, Nicholas L

2016-01-01

Background: Pulmonary Vein Antral isolation (PVAI) is currently the standard of care for both paroxysmal and persistent atrial fibrillation ablation. Reconnection to the pulmonary vein is the most common cause of recurrence of atrial fibrillation. Achieving the endpoint of bidirectional block (BDB) for cavotricuspid isthmus dependant flutter has improved our outcomes for atrial flutter ablation. With this we tried to achieve long delays in the pulmonary veins antral lines prior to complete isolation comparable to those delays found in patient with bidirectional block of atrial flutter lines. Study Objective: The objective of this paper was to evaluate feasibility and efficacy of achieving Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation. Method: A retrospective analysis was performed on patients who had paroxysmal atrial fibrillation procedures at Unity Point Methodist from January 2015 to January 2016. 20 consecutive patients with paroxysmal atrial fibrillation who had AF ablation using the Bi-Bi technique were evaluated. Result: Mean age was 63, number of antiarrhythmic used prior to ablation was 1.4, mean left atrial size was 38 mm. Mean chads score was 1.3. Mean EF was 53%. Long delays in the left antral circumferential lines were achieved with mean delay of 142 milliseconds +/-100. Also long delays in the right antral circumferential lines were achieved with mean delay of 150 milliseconds +/-80. 95 % (19/20) of patients were free of any atrial arrhythmias and were off antiarrhythmic medications for AF post procedure. There was only one transient complication in one patient who developed a moderate pericardial effusion that was successfully drained with no hemodynamic changes. The only patient who had recurrence was found to have asymptomatic AF with burden on his device <1%, this patient was also found to have non PV triggers for his AF. In patients with only PV triggered AF success rate was 100%. Conclusion: Achievement of Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation is feasible and highly effective technique in this small cohort of patients studied. We also outlined the procedure in details.

The time delay in strong gravitational lensing with Gauss-Bonnet correction

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

Man, Jingyun; Cheng, Hongbo, E-mail: jingyunman@mail.ecust.edu.cn, E-mail: hbcheng@ecust.edu.cn

2014-11-01

The time delay between two relativistic images in the strong gravitational lensing governed by Gauss-Bonnet gravity is studied. We make a complete analytical derivation of the expression of time delay in presence of Gauss-Bonnet coupling. With respect to Schwarzschild, the time delay decreases as a consequence of the shrinking of the photon sphere. As the coupling increases, the second term in the time delay expansion becomes more relevant. Thus time delay in strong limit encodes some new information about geometry in five-dimensional spacetime with Gauss-Bonnet correction.

Asymptotically optimum multialternative sequential procedures for discernment of processes minimizing average length of observations

NASA Astrophysics Data System (ADS)

Fishman, M. M.

1985-01-01

The problem of multialternative sequential discernment of processes is formulated in terms of conditionally optimum procedures minimizing the average length of observations, without any probabilistic assumptions about any one occurring process, rather than in terms of Bayes procedures minimizing the average risk. The problem is to find the procedure that will transform inequalities into equalities. The problem is formulated for various models of signal observation and data processing: (1) discernment of signals from background interference by a multichannel system; (2) discernment of pulse sequences with unknown time delay; (3) discernment of harmonic signals with unknown frequency. An asymptotically optimum sequential procedure is constructed which compares the statistics of the likelihood ratio with the mean-weighted likelihood ratio and estimates the upper bound for conditional average lengths of observations. This procedure is shown to remain valid as the upper bound for the probability of erroneous partial solutions decreases approaching zero and the number of hypotheses increases approaching infinity. It also remains valid under certain special constraints on the probability such as a threshold. A comparison with a fixed-length procedure reveals that this sequential procedure decreases the length of observations to one quarter, on the average, when the probability of erroneous partial solutions is low.

Tropospheric Parameters Determined by VLBI Within the IVS

NASA Astrophysics Data System (ADS)

Schuh, H.; Boehm, J.

2003-12-01

In April 2002 the IVS (International VLBI Service for Geodesy and Astrometry) set up the Pilot Project - Tropospheric Parameters, and the Institute of Geodesy and Geophysics (IGG), Vienna, was put in charge of coordinating the project. Seven IVS Analysis Centers have joined the project and regularly submitted their estimates of tropospheric parameters (wet and total zenith delays, horizontal gradients) for all IVS-R1 and IVS-R4 sessions since January 1st, 2002. The individual submissions are combined by a two-step procedure to obtain stable, robust and highly accurate tropospheric parameter time series with one hour resolution. The internal accuracy of the combined wet zenith delays is between 2 and 4 mm. The zenith delays derived by VLBI are compared with those provided by the International GPS Service (IGS). At sites with co-located VLBI and GPS antennas the short-term variabilities of the GPS and VLBI derived zenith delays generally show a good agreement but biases are found between the results of the two techniques. Possible reasons for these biases are discussed. Since July 1st, 2003, within the IVS the tropospheric parameters are determined as operational products. The presentation also includes the VLBI CONT02 campaign of 15 days of continuous observing in the second half of October 2002.

Two-way satellite time transfer: Overview and recent developments

NASA Technical Reports Server (NTRS)

Dejong, Gerrit

1994-01-01

The experiment using small earth stations for transatlantic two-way satellite time transfer between the USA and Germany has had its 10th anniversary this year. Pseudo-random noise coded time signals were phase modulated and demodulated at each station using a modem. Recently, during the last two weeks of Aug. 1993, six European time laboratories have used the INTELSAT 307E satellite for line-up tests and preliminary time transfer sessions using the same type of MITREX modem. The need for a uniform format for the exchange of data was felt heavily after these sessions. This problem was foreseen and addressed in international working parties. During Apr. 1993, in Task Group 7/2 of the ITU Radiocommunication Sector, a very intense discussion has taken place about what procedure should be recommended for TWSTFT and what items the header and data lines of the resulting data fields should contain. A difficulty is that two different methods of calibration of the earth station delays exist which result in different sets of delay data to be exchanged. Further study and discussions are necessary. Also, a meeting of the CCDS Working Group on TWSTFT addressed this in Oct. 1993. The outcome of the discussions and the prospect for future developments are presented.

Discovery and analysis of time delay sources in the USGS personal computer data collection platform (PCDCP) system

USGS Publications Warehouse

White, Timothy C.; Sauter, Edward A.; Stewart, Duff C.

2014-01-01

Intermagnet is an international oversight group which exists to establish a global network for geomagnetic observatories. This group establishes data standards and standard operating procedures for members and prospective members. Intermagnet has proposed a new One-Second Data Standard, for that emerging geomagnetic product. The standard specifies that all data collected must have a time stamp accuracy of ±10 milliseconds of the top-of-the-second Coordinated Universal Time. Therefore, the U.S. Geological Survey Geomagnetism Program has designed and executed several tests on its current data collection system, the Personal Computer Data Collection Platform. Tests are designed to measure the time shifts introduced by individual components within the data collection system, as well as to measure the time shift introduced by the entire Personal Computer Data Collection Platform. Additional testing designed for Intermagnet will be used to validate further such measurements. Current results of the measurements showed a 5.0–19.9 millisecond lag for the vertical channel (Z) of the Personal Computer Data Collection Platform and a 13.0–25.8 millisecond lag for horizontal channels (H and D) of the collection system. These measurements represent a dynamically changing delay introduced within the U.S. Geological Survey Personal Computer Data Collection Platform.

Human responses to bright light of different durations.

PubMed

Chang, Anne-Marie; Santhi, Nayantara; St Hilaire, Melissa; Gronfier, Claude; Bradstreet, Dayna S; Duffy, Jeanne F; Lockley, Steven W; Kronauer, Richard E; Czeisler, Charles A

2012-07-01

Light exposure in the early night induces phase delays of the circadian rhythm in melatonin in humans. Previous studies have investigated the effect of timing, intensity, wavelength, history and pattern of light stimuli on the human circadian timing system. We present results from a study of the duration–response relationship to phase-delaying bright light. Thirty-nine young healthy participants (16 female; 22.18±3.62 years) completed a 9-day inpatient study. Following three baseline days, participants underwent an initial circadian phase assessment procedure in dim light (<3 lux), and were then randomized for exposure to a bright light pulse (∼10,000 lux) of 0.2 h, 1.0 h, 2.5 h or 4.0 h duration during a 4.5 h controlled-posture episode centred in a 16 h wake episode. After another 8 h sleep episode, participants completed a second circadian phase assessment. Phase shifts were calculated from the difference in the clock time of the dim light melatonin onset (DLMO) between the initial and final phase assessments. Exposure to varying durations of bright light reset the circadian pacemaker in a dose-dependent, non-linear manner. Per minute of exposure, the 0.2 h duration was over 5 times more effective at phase delaying the circadian pacemaker (1.07±0.36 h) as compared with the 4.0 h duration (2.65±0.24 h). Acute melatonin suppression and subjective sleepiness also had a dose-dependent response to light exposure duration. These results provide strong evidence for a non-linear resetting response of the human circadian pacemaker to light duration.

Enhanced equivalence class formation by the delay and relational functions of meaningful stimuli.

PubMed

Arntzen, Erik; Nartey, Richard K; Fields, Lanny

2015-05-01

Undergraduates in six groups of 10 attempted to form three 3-node 5-member equivalence classes (A → B → C → D → E) under the simultaneous protocol. In five of six groups, all stimuli were abstract shapes; in the PIC group, C stimuli were pictures with the remainder being abstract shapes. Before class formation, participants in the Identity-S and Identity-D groups were given preliminary training to form identity conditional discriminations with the C stimuli using simultaneous and 6 s delayed matching-to-sample procedures, respectively. In the Arbitrary-S and Arbitrary-D groups, before class formation, arbitrary conditional discriminations were formed between C and X stimuli using simultaneous and 6 s delayed matching-to-sample procedures, respectively. With no preliminary training, classes in the PIC and ABS groups were formed by 80% and 0% of participants, respectively. After preliminary training, class formation (yield) increased with delay, regardless of relational type. For each of the two delays, yield was slightly greater after forming arbitrary- instead of identity-relations. Yield was greatest, however, when a class contained a meaningful stimulus (PIC). During failed class formation, probes produced experimenter-defined relations, participant-defined relations, and unsystematic responding; delay, but not the relation type in preliminary training influenced relational and indeterminate responding. These results suggest how meaningful stimuli enhance equivalence class formation. © Society for the Experimental Analysis of Behavior.

Delayed Union of a Sacral Fracture: Percutaneous Navigated Autologous Cancellous Bone Grafting and Screw Fixation

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

Huegli, R. W.; Messmer, P.; Jacob, A. L.

2003-09-15

Delayed or non-union of a sacral fracture is a serious clinical condition that may include chronic pain, sitting discomfort, gait disturbances, neurological problems, and inability to work. It is also a difficult reconstruction problem. Late correction of the deformity is technically more demanding than the primary treatment of acute pelvic injuries. Open reduction, internal fixation (ORIF), excision of scar tissue, and bone grafting often in a multi-step approach are considered to be the treatment of choice in delayed unions of the pelvic ring. This procedure implies the risk of neurological and vascular injuries, infection, repeated failure of union, incomplete correctionmore » of the deformity, and incomplete pain relief as the most important complications. We report a new approach for minimally invasive treatment of a delayed union of the sacrum without vertical displacement. A patient who suffered a Malgaigne fracture (Tile C1.3) was initially treated with closed reduction and percutaneous screw fixation (CRPF) of the posterior pelvic ring under CT navigation and plating of the anterior pelvic ring. Three months after surgery he presented with increasing hip pain caused by a delayed union of the sacral fracture. The lesion was successfully treated percutaneously in a single step procedure using CT navigation for drilling of the delayed union, autologous bone grafting, and screw fixation.« less

Interventional Radiology-Operated Cholecystoscopy for the Management of Symptomatic Cholelithiasis: Approach, Technical Success, Safety, and Clinical Outcomes.

PubMed

Patel, Nishant; Chick, Jeffrey Forris Beecham; Gemmete, Joseph J; Castle, Jordan C; Dasika, Narasimham; Saad, Wael E; Srinivasa, Ravi N

2018-05-01

The objective of our study was to report the technique, complications, and clinical outcomes of interventional radiology-operated cholecystoscopy with stone removal for the management of symptomatic cholelithiasis. Ten (77%) men and three (23%) women (mean age, 65 years) with symptomatic cholelithiasis underwent cholecystostomy followed by interventional radiology-operated cholecystoscopy with stone removal. Major comorbidities precluding cholecystectomy included prior cardiac, pulmonary, or abdominal surgery; cirrhosis; sepsis with hyponatremia; seizure disorder; developmental delay; and cholecystoduodenal fistula. Cholecystostomy access, time between cholecystostomy and cholecystoscopy, endoscopic and fragmentation devices used, technical success, procedure time, fluoroscopy time, complications, length of hospital stay, time between cholecystoscopy and cholecystostomy removal, follow-up, and acute cholecystitis recurrence were recorded. Eleven (85%) patients underwent transhepatic cholecystostomy, and two (15%) patients underwent transperitoneal cholecystostomy. The mean time from cholecystostomy to cholecystoscopy was 151 days. Flexible endoscopy was used in eight (62%) patients, rigid endoscopy in three (23%), and both flexible and rigid in two (15%). Electrohydraulic lithotripsy was used in eight procedures, nitinol baskets in seven, ultrasonic lithotripsy in two, and percutaneous thrombectomy devices in one. Primary technical success was achieved in 11 (85%) patients, and secondary technical success was achieved in 13 (100%) patients. The mean procedure time was 164 minutes, and the mean number of procedures required to clear all gallstones was 1. One (8%) patient developed acute pancreatitis, and one (8%) patient died of gastrointestinal hemorrhage. The median hospital length of stay after cholecystoscopy was 1 day for postoperative monitoring. The mean time between cholecystoscopy and cholecystostomy removal was 39 days. One (8%) patient developed recurrent acute cholecystitis 1095 days after cholecystoscopy. Interventional radiology-operated cholecystoscopy may serve as an effective method for percutaneous gallstone removal in patients with multiple comorbidities precluding cholecystectomy.

Delayed bleeding and hemorrhage of mucosal defects after gastric endoscopic submucosal dissection on second-look endoscopy.

PubMed

Ono, Shoko; Ono, Masayoshi; Nakagawa, Manabu; Shimizu, Yuichi; Kato, Mototsugu; Sakamoto, Naoya

2016-04-01

Although second-look endoscopy is performed within several days after gastric endoscopic submucosal dissection (ESD), there has been no evidence supporting the usefulness of the intervention. We investigated the relationship between delayed bleeding and hemorrhage of mucosal defects after ESD on second-look endoscopy and analyzed risk factors of active bleeding on second-look endoscopy. A total of 441 consecutive ESD cases with gastric cancer or adenoma were retrospectively analyzed. Second-look endoscopy was performed in the morning after the day of ESD. Bleeding of mucosal defects on second-look endoscopy was classified according to the Forrest classification, and active bleeding was defined as Forrest Ia or Ib. Delayed bleeding was defined as hematemesis or melena after second-look endoscopy. A total of 406 second-look endoscopies were performed, and delayed bleeding occurred in 11 patients. The incidence rate of delayed bleeding after second-look endoscopy in patients with Forrest Ia or Ib was significantly higher than that in patients with Forrest IIa, IIb or III (7.69 vs. 2.02 %, p < 0.05). Complication of a histological ulcer, large size of the resected specimen and long ESD procedure time were shown to be risk factors for hemorrhage of mucosal defects after ESD on second-look endoscopy by univariate analysis. Multivariate analysis indicated that only large size of the resected specimen was a risk factor. In a specimen size of >35 mm, the odds ratio of active bleeding on second-look endoscopy was 1.9. Active bleeding of mucosal defects on second-look endoscopy is a risk factor for delayed bleeding.

Delays in the operating room: signs of an imperfect system.

PubMed

Wong, Janice; Khu, Kathleen Joy; Kaderali, Zul; Bernstein, Mark

2010-06-01

Delays in the operating room have a negative effect on its efficiency and the working environment. In this prospective study, we analyzed data on perioperative system delays. One neurosurgeon prospectively recorded all errors, including perioperative delays, for consecutive patients undergoing elective procedures from May 2000 to February 2009. We analyzed the prevalence, causes and impact of perioperative system delays that occurred in one neurosurgeon's practice. A total of 1531 elective surgical cases were performed during the study period. Delays were the most common type of error (33.6%), and more than half (51.4%) of all cases had at least 1 delay. The most common cause of delay was equipment failure. The first cases of the day and cranial cases had more delays than subsequent cases and spinal cases, respectively. A delay in starting the first case was associated with subsequent delays. Delays frequently occur in the operating room and have a major effect on patient flow and resource utilization. Thorough documentation of perioperative delays provides a basis for the development of solutions for improving operating room efficiency and illustrates the principles underlying the causes of operating room delays across surgical disciplines.

Rap system of stress stimulation can promote bone union after lower tibial bone fracture: a clinical research.

PubMed

Yao, Jian-fei; Shen, Jia-zuo; Li, Da-kun; Lin, Da-sheng; Li, Lin; Li, Qiang; Qi, Peng; Lian, Ke-jian; Ding, Zhen-qi

2012-01-01

Lower tibial bone fracture may easily cause bone delayed union or nonunion because of lacking of dynamic mechanical load. Research Group would design a new instrument as Rap System of Stress Stimulation (RSSS) to provide dynamic mechanical load which would promote lower tibial bone union postoperatively. This clinical research was conducted from January 2008 to December 2010, 92 patients(male 61/female 31, age 16-70 years, mean 36.3 years) who suffered lower tibial bone closed fracture were given intramedullary nail fixation and randomly averagely separated into experimental group and control group(according to the successively order when patients went for the admission procedure). Then researchers analysed the clinical healing time, full weight bearing time, VAS (Visual Analogue Scales) score and callus growth score of Lane-Sandhu in 3,6,12 months postoperatively. The delayed union and nonunion rates were compared at 6 and 12 months separately. All the 92 patients had been followed up (mean 14 months). Clinical bone healing time in experimental group was 88.78±8.80 days but control group was 107.91±9.03 days. Full weight bearing time in experimental group was 94.07±9.81 days but control group was 113.24±13.37 days respectively (P<0.05). The delayed union rate in 6 months was 4.3% in experimental group but 10.9% in control group(P<0.05). The nonunion rate in 12 months was 6.5% in experimental group but 19.6% in control group(P<0.05). In 3, 6, 12 months postoperatively, VAS score and Lane-Sandhu score in experimental group had more significantly difference than them in control group. RSSS can intermittently provide dynamic mechanical load and stimulate callus formation, promote lower tibial bone union, reduce bone delayed union or nonunion rate. It is an adjuvant therapy for promoting bone union after lower tibial bone fracture.

RNA splicing regulates the temporal order of TNF-induced gene expression.

PubMed

Hao, Shengli; Baltimore, David

2013-07-16

When cells are induced to express inflammatory genes by treatment with TNF, the mRNAs for the induced genes appear in three distinct waves, defining gene groups I, II, and III, or early, intermediate, and late genes. To examine the basis for these different kinetic classes, we have developed a PCR-based procedure to distinguish pre-mRNAs from mRNAs. It shows that the three groups initiate transcription virtually simultaneously but that delays in splicing characterize groups II and III. We also examined the elongation times, concluding that pre-mRNA synthesis is coordinate but splicing differences directly regulate the timing of mRNA production.

Therapeutic outcomes of endoscopic submucosal dissection of differentiated early gastric cancer in a Western endoscopy setting (with video).

PubMed

Emura, Fabian; Mejía, Juan; Donneys, Alberto; Ricaurte, Orlando; Sabbagh, Luis; Giraldo-Cadavid, Luis; Oda, Ichiro; Saito, Yutaka; Osorio, Camilo

2015-11-01

Large multicenter gastric cancer endoscopic submucosal dissection (ESD) studies conducted at major Japanese institutions have reported en bloc resection, en bloc tumor-free margin resection, and curative resection rates of 92.7% to 96.1%, 82.6% to 94.5%, and 73.6% to 85.4%, respectively, with delayed bleeding and perforation rates of 0.6% to 6.0% and 3.6% to 4.7%, respectively. Although ESD is currently an alternative treatment in some countries, particularly in Asia, it remains uncertain whether ESD therapeutic outcomes in Western endoscopy settings can be comparable to those achieved in Japan. To evaluate the ESD therapeutic outcomes for differentiated early gastric cancer (EGC) in a Western endoscopy setting. Consecutive case series performed by an expertly trained Western endoscopist. Fifty-three patients with 54 lesions. ESD for early gastric cancers (T1) satisfying expanded inclusion criteria. En bloc resection, en bloc tumor-free margin resection, and curative resection rates were 98%, 93%, and 83%, respectively. The delayed bleeding rate was 7%, and the perforation rate was 4%. The mean patient age was 67 years, and the mean tumor size was 19.8 mm, with 54% of the lesions located in the lesser curvature. The median procedure time was 61 minutes, with ESD procedures 60 minutes or longer associated with submucosal fibrosis (P < .001) and tumor size 25 mm or larger (P = .03). In every ESD procedure, both circumferential incision and submucosal dissection were performed by using a single knife. Two of the 4 delayed bleeding cases required surgery, and all perforations were successfully managed by using endoscopic clips. Long-term outcome data are currently unavailable. ESD for differentiated EGC resulted in favorable therapeutic outcomes in a Western endoscopy setting comparable to those achieved at major Japanese institutions. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

5 CFR 9701.512 - Conferring on procedures for the exercise of management rights.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Conferring on procedures for the exercise... Conferring on procedures for the exercise of management rights. (a) As provided by § 9701.511(c), management... this section will delay the exercise of a management right under § 9701.511(a)(1) and (2). (d...

5 CFR 9701.512 - Conferring on procedures for the exercise of management rights.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Conferring on procedures for the exercise... Conferring on procedures for the exercise of management rights. (a) As provided by § 9701.511(c), management... this section will delay the exercise of a management right under § 9701.511(a)(1) and (2). (d...

5 CFR 9701.512 - Conferring on procedures for the exercise of management rights.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Conferring on procedures for the exercise... Conferring on procedures for the exercise of management rights. (a) As provided by § 9701.511(c), management... this section will delay the exercise of a management right under § 9701.511(a)(1) and (2). (d...

5 CFR 9701.512 - Conferring on procedures for the exercise of management rights.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Conferring on procedures for the exercise... Conferring on procedures for the exercise of management rights. (a) As provided by § 9701.511(c), management... this section will delay the exercise of a management right under § 9701.511(a)(1) and (2). (d...

Delay Discounting in Lewis and Fischer 344 Rats: Steady-State and Rapid-Determination Adjusting-Amount Procedures

ERIC Educational Resources Information Center

Stein, Jeffrey S.; Pinkston, Jonathan W.; Brewer, Adam T.; Francisco, Monica T.; Madden, Gregory J.

2012-01-01

Lewis rats have been shown to make more impulsive choices than Fischer 344 rats in discrete trial choice procedures that arrange fixed (i.e., nontitrating) reinforcement parameters. However, nontitrating procedures yield only gross estimates of preference, as choice measures in animal subjects are rarely graded at the level of the individual…

Audit of thrombolysis initiated in an accident and emergency department.

PubMed Central

Nee, P A; Gray, A J; Martin, M A

1994-01-01

Early thrombolytic therapy after acute myocardial infarction is important in reducing mortality. To evaluate a system for reducing in-hospital delays to thrombolysis pain to needle and door to needle times to thrombolysis were audited in a major accident and emergency (A and E) department of a district general hospital and its coronary care unit (CCU), situated about 5 km away. Baseline performance over six months was assessed retrospectively from notes of 43 consecutive patients (group 1) transferred to the CCU before receiving thrombolysis. Subsequently, selected patients (23) were allowed to receive thrombolysis in the A and E department before transfer to the CCU. The agent was administered by medical staff in the department after receiving oral confirmation of myocardial infarction from the admitting medical officer in the CCU on receipt of fax transmission of the electrocardiogram. A second prospective audit during six months from the start of the new procedure established time intervals in 23 patients eligible to receive thrombolysis in the A and E department (group 2b) and 30 ineligible patients who received thrombolysis in the CCU (group 2a). The groups did not differ significantly in case mix, pre-hospital delay, or transfer time to the CCU. In group 2b door to needle time and pain to needle time were reduced significantly (geometric mean 38 min v 121 min (group 2a) and 128 min (group 1); 141 min v 237 min (group 2a) and 242 min (group 1) respectively, both p < 0.0001). The incidence of adverse effects was not significantly different. Nine deaths occurred (six in group 1, three in group 2b), an in-hospital mortality of 9.9%. Thrombolysis can be safely instituted in the A and E department in selected patients, significantly reducing delay to treatment. PMID:10136256

Effect of Time Interval Between Tumescent Local Anesthesia Infiltration and Start of Surgery on Operative Field Visibility in Hand Surgery Without Tourniquet.

PubMed

Bashir, Muhammad Mustehsan; Qayyum, Rehan; Saleem, Muhammad Hammad; Siddique, Kashif; Khan, Farid Ahmad

2015-08-01

To determine the optimal time interval between tumescent local anesthesia infiltration and the start of hand surgery without a tourniquet for improved operative field visibility. Patients aged 16 to 60 years who needed contracture release and tendon repair in the hand were enrolled from the outpatient clinic. Patients were randomized to 10-, 15-, or 25-minute intervals between tumescent anesthetic solution infiltration (0.18% lidocaine and 1:221,000 epinephrine) and the start of surgery. The end point of tumescence anesthetic infiltration was pale and firm skin. The surgical team was blinded to the time of anesthetic infiltration. At the completion of the procedure, the surgeon and the first assistant rated the operative field visibility as excellent, fair, or poor. We used logistic regression models without and with adjustment for confounding variables. Of the 75 patients enrolled in the study, 59 (79%) were males, 7 were randomized to 10-minute time intervals (further randomization was stopped after interim analysis found consistently poor operative field visibility), and 34 were randomized to the each of the 15- and 25-minute groups. Patients who were randomized to the 25-minute delay group had 29 times higher odds of having an excellent operative visual field than those randomized to the 15-minute delay group. After adjusting for age, sex, amount of tumescent solution infiltration, and duration of operation, the odds ratio remained highly significant. We found that an interval of 25 minutes provides vastly superior operative field visibility; 10-minute delay had the poorest results. Therapeutic I. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Choice in situations of time-based diminishing returns: immediate versus delayed consequences of action.

PubMed Central

Hackenberg, T D; Hineline, P N

1992-01-01

Pigeons chose between two schedules of food presentation, a fixed-interval schedule and a progressive-interval schedule that began at 0 s and increased by 20 s with each food delivery provided by that schedule. Choosing one schedule disabled the alternate schedule and stimuli until the requirements of the chosen schedule were satisfied, at which point both schedules were again made available. Fixed-interval duration remained constant within individual sessions but varied across conditions. Under reset conditions, completing the fixed-interval schedule not only produced food but also reset the progressive interval to its minimum. Blocks of sessions under the reset procedure were interspersed with sessions under a no-reset procedure, in which the progressive schedule value increased independent of fixed-interval choices. Median points of switching from the progressive to the fixed schedule varied systematically with fixed-interval value, and were consistently lower during reset than during no-reset conditions. Under the latter, each subject's choices of the progressive-interval schedule persisted beyond the point at which its requirements equaled those of the fixed-interval schedule at all but the highest fixed-interval value. Under the reset procedure, switching occurred at or prior to that equality point. These results qualitatively confirm molar analyses of schedule preference and some versions of optimality theory, but they are more adequately characterized by a model of schedule preference based on the cumulated values of multiple reinforcers, weighted in inverse proportion to the delay between the choice and each successive reinforcer. PMID:1548449

A Language Training Strategy for Teaching Young Language-Delayed Children a Functional Syntactical Form.

ERIC Educational Resources Information Center

Hester, Peggy; Hendrickson, Jo

A modeling procedure involving dynamic interactions was used to train three language-delayed preschool children to emit five-element syntactic responses. A single-subject multiple baseline design using within- and across-subject replication was employed to study the acquisition of expanded "agent-action-object" sentences and the…

Signal-Detection Analyses of Conditional Discrimination and Delayed Matching-to-Sample Performance

ERIC Educational Resources Information Center

Alsop, Brent

2004-01-01

Quantitative analyses of stimulus control and reinforcer control in conditional discriminations and delayed matching-to-sample procedures often encounter a problem; it is not clear how to analyze data when subjects have not made errors. The present article examines two common methods for overcoming this problem. Monte Carlo simulations of…

77 FR 13978 - Railroad Workplace Safety; Adjacent-Track On-Track Safety for Roadway Workers

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-08

... rule; delay of effective date and request for comments. SUMMARY: This document delays the effective date of the final rule published November 30, 2011, and scheduled to take effect on May 1, 2012. The final rule mandates that roadway workers comply with specified on-track safety procedures that railroads...

40 CFR 147.2906 - Emergency permits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... substantial delay in oil or gas production, and injection will not result in movement of fluid into an USDW... permits to avoid a substantial delay in oil or gas production shall be issued only after a complete permit... notice procedure for a draft permit within 10 days after issuance. (3) An emergency permit may be oral or...

Problems and Limitations in Studies on Screening for Language Delay

ERIC Educational Resources Information Center

Eriksson, Marten; Westerlund, Monica; Miniscalco, Carmela

2010-01-01

This study discusses six common methodological limitations in screening for language delay (LD) as illustrated in 11 recent studies. The limitations are (1) whether the studies define a target population, (2) whether the recruitment procedure is unbiased, (3) attrition, (4) verification bias, (5) small sample size and (6) inconsistencies in choice…

Integrated communication and control systems. II - Design considerations

NASA Technical Reports Server (NTRS)

Ray, Asok; Halevi, Yoram

1988-01-01

The ICCS design issues for nonperiodic and stochastic delays are addressed and the framework for alternative design procedures is outlined. The impact of network-induced delays on system stability is investigated and their physical significance is demonstrated using a simulation. The negative effects of vacant sampling and message rejection at the controller are demonstrated.

32 CFR 536.132 - Procedure for processing UCMJ claims.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the claim determines there is good cause for delay. Lack of knowledge of the existence of Article 139, or lack of knowledge of the identity of the offender, are examples of good cause for delay. (b) Form... the claim to the commander who exercises SPCMCA jurisdiction over the soldier for assessment. The...

Establishing Auditory-Tactile-Visual Equivalence Classes in Children with Autism and Developmental Delays

ERIC Educational Resources Information Center

Mullen, Stuart; Dixon, Mark R.; Belisle, Jordan; Stanley, Caleb

2017-01-01

The current study sought to evaluate the efficacy of a stimulus equivalence training procedure in establishing auditory-tactile-visual stimulus classes with 2 children with autism and developmental delays. Participants were exposed to vocal-tactile (A-B) and tactile-picture (B-C) conditional discrimination training and were tested for the…

Immediate Titanium Mesh Implantation for Patients with Postcraniotomy Neurosurgical Site Infections: Safe and Aesthetic Alternative Procedure?

PubMed

Ehrlich, Gregory; Kindling, Stefanie; Wenz, Holger; Hänggi, Daniel; Schulte, Dirk Michael; Schmiedek, Peter; Seiz-Rosenhagen, Marcel

2017-03-01

Surgical site infection (SSI) is one of the main complications after craniotomy. The incidence is up to 11% in the literature. The established procedure is debridement, removal of the bone flap, and delayed cranioplasty. Delayed cranioplasty has several disadvantages. A promising approach is the immediate titanium mesh implantation at the time of wound revision. We report our experience with this technique regarding outcome measured by reinfection rates and patient satisfaction. Patients treated in our department from January 2013 to October 2014 with SSI after craniotomy for brain tumor, trauma, or vascular pathologies were prospectively collected. In all these patients, immediate titanium mesh implantation after bone flap removal was performed. Primary outcome parameters were the reinfection rate and patient satisfaction via self-designed questionnaires in a follow-up period >3 months. Twenty-four patients were included within the study period. Main risk factors causing SSI were previous steroid medication (62.5%), cranial radiation therapy (42%), cerebrospinal fluid fistula after initial surgery (12.5%), and diabetes mellitus (25%). The follow-up was >3 months after titanium mesh cranioplasty (mean 4.6 months; range 3-6 months). No recurrent infection was detected in the study group. In 2 cases, reoperation was necessary. The returning questionnaires showed a high satisfaction rate with the cosmetic result. Our small series seems to confirm that immediate titanium mesh implantation for patients with postcraniotomy SSI is a cost-effective, safe, and cosmetically suitable alternative to delayed cranioplasty in selected patients without hydrocephalus or persistent cerebrospinal fluid fistula. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of Time Delay on Recognition Memory for Pictures: The Modulatory Role of Emotion

PubMed Central

Wang, Bo

2014-01-01

This study investigated the modulatory role of emotion in the effect of time delay on recognition memory for pictures. Participants viewed neutral, positive and negative pictures, and took a recognition memory test 5 minutes, 24 hours, or 1 week after learning. The findings are: 1) For neutral, positive and negative pictures, overall recognition accuracy in the 5-min delay did not significantly differ from that in the 24-h delay. For neutral and positive pictures, overall recognition accuracy in the 1-week delay was lower than in the 24-h delay; for negative pictures, overall recognition in the 24-h and 1-week delay did not significantly differ. Therefore negative emotion modulates the effect of time delay on recognition memory, maintaining retention of overall recognition accuracy only within a certain frame of time. 2) For the three types of pictures, recollection and familiarity in the 5-min delay did not significantly differ from that in the 24-h and the 1-week delay. Thus emotion does not appear to modulate the effect of time delay on recollection and familiarity. However, recollection in the 24-h delay was higher than in the 1-week delay, whereas familiarity in the 24-h delay was lower than in the 1-week delay. PMID:24971457

Feasibility of a cardiologist-only approach to sedation for electrical cardioversion of atrial fibrillation: a randomized, open-blinded, prospective study.

PubMed

Guerra, Federico; Pavoni, Ilaria; Romandini, Andrea; Baldetti, Luca; Matassini, Maria Vittoria; Brambatti, Michela; Luzi, Mario; Pupita, Giuseppe; Capucci, Alessandro

2014-10-20

Sedation with propofol should be administered by personnel trained in advanced airway management. To overcome this limitation, the use of short acting benzodiazepines by cardiologists spread widely, causing concerns about the safety of this procedure in the absence of anesthesiology assistance. The aim of the study was to compare feasibility of a cardiologist-only approach with an anesthesiologist-assisted sedation protocol during elective direct-current cardioversion (DCC) of persistent atrial fibrillation (AF). This prospective, open-blinded, randomized study included 204 patients, which were admitted for scheduled cardioversion of persistent AF, and randomized in a 1:1 fashion to either propofol or midazolam treatment arm. Patients in the propofol group underwent DCC with anesthesiologist assistance, while patients in the midazolam group saw the cardiologist as the only responsible for both sedation and DCC. Twenty-three adverse events occurred: 13 in the propofol group and 10 in the midazolam group (p=NS). Most of them were related to bradyarrhythmias and respiratory depressions. There was no need of intubation or other advanced resuscitation techniques in any of these patients. No differences were found regarding procedure tolerability and safety endpoints between the two groups. DCC procedures with anesthesiology support were burdened by higher delay from scheduled time and higher costs. Sedation with midazolam administered by cardiologist-only appears to be as safe as sedation with propofol and anesthesiologist assistance. Adverse events were few in both groups and easily handled by the cardiologist alone. A cardiologist-only approach to sedation provides less procedural delay, thus being easier to schedule and correlated with fewer costs. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Why Do Long-Distance Travelers Have Improved Pancreatectomy Outcomes?

PubMed

Jindal, Manila; Zheng, Chaoyi; Quadri, Humair S; Ihemelandu, Chukwuemeka U; Hong, Young K; Smith, Andrew K; Dudeja, Vikas; Shara, Nawar M; Johnson, Lynt B; Al-Refaie, Waddah B

2017-08-01

Centralization of complex surgical care has led patients to travel longer distances. Emerging evidence suggested a negative association between increased travel distance and mortality after pancreatectomy. However, the reason for this association remains largely unknown. We sought to unravel the relationships among travel distance, receiving pancreatectomy at high-volume hospitals, delayed surgery, and operative outcomes. We identified 44,476 patients who underwent pancreatectomy for neoplasms between 2004 and 2013 at the reporting facility from the National Cancer Database. Multivariable analyses were performed to examine the independent relationships between increments in travel distance mortality (30-day and long-term survival) after adjusting for patient demographics, comorbidity, cancer stage, and time trend. We then examined how additional adjustment of procedure volume affected this relationship overall and among rural patients. Median travel distance to undergo pancreatectomy increased from 16.5 to 18.7 miles (p for trend < 0.001). Although longer travel distance was associated with delayed pancreatectomy, it was also related to higher odds of receiving pancreatectomy at a high-volume hospital and lower postoperative mortality. In multivariable analysis, difference in mortality among patients with varying travel distance was attenuated by adjustment for procedure volume. However, longest travel distance was still associated with a 77% lower 30-day mortality rate than shortest travel among rural patients, even when accounting for procedure volume. Our large national study found that the beneficial effect of longer travel distance on mortality after pancreatectomy is mainly attributable to increase in procedure volume. However, it can have additional benefits on rural patients that are not explained by volume. Distance can represent a surrogate for rural populations. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Teaching self-control to small groups of dually diagnosed adults.

PubMed

Dixon, M R; Holcomb, S

2000-01-01

The present study examined the use of a progressive delay procedure to teach self-control to two groups of dually diagnosed adults. When given a choice between an immediate smaller reinforcer and a larger delayed reinforcer, both groups chose the smaller reinforcer during baseline. During treatment, progressive increases in work requirements for gaining access to a larger reinforcer resulted in both groups selecting larger delayed reinforcers. The results are discussed with respect to increasing cooperative work behavior and self-control.

'Informed and uninformed decision making'--women's reasoning, experiences and perceptions with regard to advanced maternal age and delayed childbearing: a meta-synthesis.

PubMed

Cooke, Alison; Mills, Tracey A; Lavender, Tina

2010-10-01

To identify what factors affect women's decisions to delay childbearing, and to explore women's experiences and their perceptions of associated risks. Systematic procedures were used for search strategy, study selection, data extraction and analysis. Findings were synthesised using an approach developed from meta-ethnography. We included qualitative papers, not confined to geographical area (1980-2009). Databases included CINAHL, MEDLINE, EMBASE, PsycInfo, ASSIA, MIDIRS, British Nursing Index and the National Research Register. We selected qualitative empirical studies exploring the views and experiences of women of advanced maternal age who were childless or primigravidae with a singleton pregnancy or primiparous. Twelve papers fulfilled the selection criteria and were included for synthesis. Women appear to face an issue of 'informed and uninformed decision making'; those who believe they are informed but may not be, those who are not informed and find out they are at risk once pregnant, and those who are well informed but choose to delay pregnancy anyway. Maternity services could provide information to enable informed choice regarding timing of childbearing. Health professionals need to be mindful of the fact that women delay childbearing for various reasons. A strategy of pre-conception education may be beneficial in informing childbearing decisions. Obstetricians and midwives should be sensitive to the fact that women may not be aware of all the risks associated with delayed childbearing. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Power cepstrum technique with application to model helicopter acoustic data

NASA Technical Reports Server (NTRS)

Martin, R. M.; Burley, C. L.

1986-01-01

The application of the power cepstrum to measured helicopter-rotor acoustic data is investigated. A previously applied correction to the reconstructed spectrum is shown to be incorrect. For an exact echoed signal, the amplitude of the cepstrum echo spike at the delay time is linearly related to the echo relative amplitude in the time domain. If the measured spectrum is not entirely from the source signal, the cepstrum will not yield the desired echo characteristics and a cepstral aliasing may occur because of the effective sample rate in the frequency domain. The spectral analysis bandwidth must be less than one-half the echo ripple frequency or cepstral aliasing can occur. The power cepstrum editing technique is a useful tool for removing some of the contamination because of acoustic reflections from measured rotor acoustic spectra. The cepstrum editing yields an improved estimate of the free field spectrum, but the correction process is limited by the lack of accurate knowledge of the echo transfer function. An alternate procedure, which does not require cepstral editing, is proposed which allows the complete correction of a contaminated spectrum through use of both the transfer function and delay time of the echo process.

Mathematical problems in children with developmental coordination disorder.

PubMed

Pieters, Stefanie; Desoete, Annemie; Van Waelvelde, Hilde; Vanderswalmen, Ruth; Roeyers, Herbert

2012-01-01

Developmental coordination disorder (DCD) is a heterogeneous disorder, which is often co-morbid with learning disabilities. However, mathematical problems have rarely been studied in DCD. The aim of this study was to investigate the mathematical problems in children with various degrees of motor problems. Specifically, this study explored if the development of mathematical skills in children with DCD is delayed or deficient. Children with DCD performed significantly worse for number fact retrieval and procedural calculation in comparison with age-matched control children. Moreover, children with mild DCD differed significantly from children with severe DCD on both number fact retrieval and procedural calculation. In addition, we found a developmental delay of 1 year for number fact retrieval in children with mild DCD and a developmental delay of 2 years in children with severe DCD. No evidence for a mathematical deficit was found. Diagnostic implications are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Process Improvement Initiative for the Perioperative Management of Patients With a Cardiovascular Implantable Electronic Device.

PubMed

Ellis, Margaret K Menzel; Treggiari, Miriam M; Robertson, Jamie M; Rozner, Marc A; Graven, Peter F; Aziz, Michael F; Merkel, Matthias J; Kahl, Edward A; Cohen, Norman A; Stecker, Eric C; Schulman, Peter M

2017-07-01

Economic, personnel, and procedural challenges often complicate and interfere with efficient and safe perioperative care of patients with cardiovascular implantable electronic devices (CIEDs). In the context of a process improvement initiative, we created and implemented a comprehensive anesthesiologist-run perioperative CIED service to respond to all routine requests for perioperative CIED consultations at a large academic medical center. This study was designed to determine whether this new care model was associated with improved operating room efficiency, reduced institutional cost, and adequate patient safety. We included patients with a CIED and a concurrent cohort of patients with the same eligibility criteria but without a CIED who underwent first-case-of-the-day surgery during the periods between February 1, 2008, and August 17, 2010 (preintervention) and between March 4, 2012, and August 1, 2014 (postintervention). The primary end point was delay in first-case-of-the day start time. We used multiple linear regression to compare delays in start times during the preintervention and postintervention periods and to adjust for potential confounders. A patient safety database was queried for CIED-related complications. Cost analysis was based on labor minutes saved and was calculated using nationally published administrative estimates. A total of 18,148 first-case surgical procedures were performed in 15,100 patients (preintervention period-7293 patients and postintervention period-7807 patients). Of those, 151 (2.1%) patients had a CIED in the preintervention period, and 146 (1.9%) had a CIED in the postintervention period. After adjustment for imbalances in baseline characteristics (age, American Society of Anesthesiologists physical status, and surgical specialty), the difference in mean first-case start delay between the postintervention and preintervention periods in the cohort of patients with a CIED was -16.7 minutes (95% confidence interval [CI], -26.1 to -7.2). The difference in mean delay between the postintervention and preintervention periods in the cohort without a CIED was -4.7 minutes (95% CI, -5.4 to -3.9). There were 3 CIED-related adverse events during the preintervention period and none during the postintervention period. Based on reduction in first-case start delay, the intervention was associated with cost savings (estimated institutional savings $14,102 annually, or $94.06 per CIED patient), with a return on investment ratio of 2.18 over the course of the postintervention period. Based on our experience, specially trained anesthesiologists can provide efficient and safe perioperative care for patients with CIEDs. Other centers may consider implementing a similar strategy as our specialty adopts the perioperative surgical home model.

Angular dependence of EWS time delay for photoionization of @Xe

NASA Astrophysics Data System (ADS)

Mandal, Ankur; Deshmukh, Pranawa; Kheifets, Anatoli; Dolmatov, Valeriy; Manson, Steven

2017-04-01

Interference between photoionization channels leads to angular dependence in photoionization time delay. Angular dependence is found to be a common effect for two-photon absorption experiments very recently. The effect of confinement on the time delay where each partial wave contributions to the ionization are studied. In this work we report angular dependence and confinement effects on Eisenbud-Wigner-Smith (EWS) time delay in atomic photoionization. Using and we computed the EWS time delay for free and confined Xe atom for photoionization from inner 4d3/2 and 4d5/2 and outer 5p1/2 and 5p3/2 subshells at various angles. The calculated EWS time delay is few tens to few hundreds of attoseconds (10-18 second). The photoionization time delay for @Xe follows that in the free Xe atom on which the confinement oscillations are built. The present work reveals the effect of confinement on the photoionization time delay at different angles between photoelectron ejection and the photon polarization.

Crash testing difference-smoothing algorithm on a large sample of simulated light curves from TDC1

NASA Astrophysics Data System (ADS)

Rathna Kumar, S.

2017-09-01

In this work, we propose refinements to the difference-smoothing algorithm for the measurement of time delay from the light curves of the images of a gravitationally lensed quasar. The refinements mainly consist of a more pragmatic approach to choose the smoothing time-scale free parameter, generation of more realistic synthetic light curves for the estimation of time delay uncertainty and using a plot of normalized χ2 computed over a wide range of trial time delay values to assess the reliability of a measured time delay and also for identifying instances of catastrophic failure. We rigorously tested the difference-smoothing algorithm on a large sample of more than thousand pairs of simulated light curves having known true time delays between them from the two most difficult 'rungs' - rung3 and rung4 - of the first edition of Strong Lens Time Delay Challenge (TDC1) and found an inherent tendency of the algorithm to measure the magnitude of time delay to be higher than the true value of time delay. However, we find that this systematic bias is eliminated by applying a correction to each measured time delay according to the magnitude and sign of the systematic error inferred by applying the time delay estimator on synthetic light curves simulating the measured time delay. Following these refinements, the TDC performance metrics for the difference-smoothing algorithm are found to be competitive with those of the best performing submissions of TDC1 for both the tested 'rungs'. The MATLAB codes used in this work and the detailed results are made publicly available.

Delay Discounting in C57BL/6J and DBA/2J Mice: Adolescent-Limited and Life-Persistent Patterns of Impulsivity

PubMed Central

Pinkston, Jonathan W.; Lamb, R. J.

2011-01-01

Impulsivity is a defining characteristic of adolescence. Compared to adults, for example, adolescents engage in higher rates of drug and alcohol experimentation, risky sexual practices, and criminal activity. Such behavior may reflect reduced sensitivity to long-term consequences for behavior during adolescence. Recently, our lab has attempted to refine mouse procedures to study developmental trends in decision making in the laboratory. In the present experiment, we examined sensitivity to delayed rewards in C57BL/6J (B6) and DBA/2J (D2) mice during adolescence and adulthood using an adaptation of a two-week delay discounting procedure developed by Adriani & Laviola (2003) [Behavioral Neuroscience, 117, 695-703]. During training, mice could choose between a 20- or 100-ul drop of milk delivered after a 1-s delay. During testing, the delay to the large drop of milk was increased from 1 to 100 seconds. As the delay to the larger volume increased, preference shifted to the smaller, more immediate option. In adolescence, both strains showed similar shifts in preference. In contrast, adult B6 mice were less sensitive to increasing delays than were adult D2 mice, who continued to perform much as their adolescent counterparts. A subsequent resistance-to-extinction test ruled out the possibility that the slower change in the adult B6 mice was due to perseverative responding. The present findings suggest that B6 and D2 strains may be differentially suited to uncovering the biological mechanism of short-term and long-term patterns of impulsive behavior. PMID:21463022

Dynamics of initial colonization of nonconserved perennial ryegrass by anaerobic fungi in the bovine rumen.

PubMed

Edwards, Joan E; Kingston-Smith, Alison H; Jimenez, Hugo R; Huws, Sharon A; Skøt, Kirsten P; Griffith, Gareth W; McEwan, Neil R; Theodorou, Michael K

2008-12-01

Anaerobic fungi (Neocallimastigales) are active degraders of fibrous plant material in the rumen. However, only limited information is available relating to how quickly they colonize ingested feed particles. The aim of this study was to determine the dynamics of initial colonization of forage by anaerobic fungi in the rumen and the impact of different postsampling wash procedures used to remove loosely associated microorganisms. Neocallimastigales-specific molecular techniques were optimized to ensure maximal coverage before application to assess the population size (quantitative PCR) and composition (automated ribosomal intergenic spacer analysis) of the colonizing anaerobic fungi. Colonization of perennial ryegrass (PRG) was evident within 5 min, with no consistent effect of time or wash procedure on fungal population composition. Wash procedure had no effect on population size unlike time, which had a significant effect. Colonizing fungal population size continued to increase over the incubation period after an initial lag of c. 4 min. This dynamic differs from that reported previously for rumen bacteria, where substantial colonization of PRG occurred within 5 min. The observed delay in colonization of plant material by anaerobic fungi is suggested to be primarily mediated by the time taken for fungal zoospores to locate, attach and encyst on plant material.

A robust and high-performance queue management controller for large round trip time networks

NASA Astrophysics Data System (ADS)

Khoshnevisan, Ladan; Salmasi, Farzad R.

2016-05-01

Congestion management for transmission control protocol is of utmost importance to prevent packet loss within a network. This necessitates strategies for active queue management. The most applied active queue management strategies have their inherent disadvantages which lead to suboptimal performance and even instability in the case of large round trip time and/or external disturbance. This paper presents an internal model control robust queue management scheme with two degrees of freedom in order to restrict the undesired effects of large and small round trip time and parameter variations in the queue management. Conventional approaches such as proportional integral and random early detection procedures lead to unstable behaviour due to large delay. Moreover, internal model control-Smith scheme suffers from large oscillations due to the large round trip time. On the other hand, other schemes such as internal model control-proportional integral and derivative show excessive sluggish performance for small round trip time values. To overcome these shortcomings, we introduce a system entailing two individual controllers for queue management and disturbance rejection, simultaneously. Simulation results based on Matlab/Simulink and also Network Simulator 2 (NS2) demonstrate the effectiveness of the procedure and verify the analytical approach.

The need for GPS standardization

NASA Technical Reports Server (NTRS)

Lewandowski, Wlodzimierz W.; Petit, Gerard; Thomas, Claudine

1992-01-01

A desirable and necessary step for improvement of the accuracy of Global Positioning System (GPS) time comparisons is the establishment of common GPS standards. For this reason, the CCDS proposed the creation of a special group of experts with the objective of recommending procedures and models for operational time transfer by GPS common-view method. Since the announcement of the implementation of Selective Availability at the end of last spring, action has become much more urgent and this CCDS Group on GPS Time Transfer Standards has now been set up. It operates under the auspices of the permanent CCDS Working Group on TAI and works in close cooperation with the Sub-Committee on Time of the Civil GPS Service Interface Committee (CGSIC). Taking as an example the implementation of SA during the first week of July 1991, this paper illustrates the need to develop urgently at least two standardized procedures in GPS receiver software: monitoring GPS tracks with a common time scale and retaining broadcast ephemeris parameters throughout the duration of a track. Other matters requiring action are the adoption of common models for atmospheric delay, a common approach to hardware design and agreement about short-term data processing. Several examples of such deficiencies in standardization are presented.

Development of visuospatial short-term memory in the second half of the 1st year.

PubMed

Pelphrey, Kevin A; Reznick, J Steven; Davis Goldman, Barbara; Sasson, Noah; Morrow, Judy; Donahoe, Andrea; Hodgson, Katharine

2004-09-01

Eighty 5.5- to 12.5-month-old infants participated in 4 delayed-response procedures challenging shortterm visuospatial memory (STVM), 2 that varied the time between presentation and search and 2 that varied the number of locations. Within each type of challenge, 1 task required a gaze response and 1 required a reach response. There was little improvement in STVM performance from 5.5 to 8 months and linear improvement in the percentage correct from 8 to 12 months, with overall STVM performance accounting for 66% of the variance in age. Improvement in searching multiple locations lagged behind improvement in spanning longer delays. Memory scores did not vary for the visual and manual tasks. Perseveration was greatest for reach responses, increased with challenge, and decreased with age. ((c) 2004 APA, all rights reserved) Copyright 2004 American Psychological Association

Delayed manifestation of bilateral scleral thinning after I-BRITE® procedure and review of literature for cosmetic eye-whitening procedures

PubMed Central

Moshirfar, Majid; McCaughey, Michael V; Fenzl, Carlton R; Santiago-Caban, Luis; Kramer, Gregory D; Mamalis, Nick

2015-01-01

Purpose To report a case of delayed-onset bilateral scleral thinning and calcium deposition following a cosmetic ocular-whitening procedure (I-BRITE®). Methods A 33-year-old male patient with a history of right-sided ptosis repair and left-sided anterior uveitis had previously undergone bilateral I-BRITE treatment for chronic conjunctival hyperemia. Four years after the procedure, the patient was referred to our institution with bilateral scleral thinning and overlying calcific depositions. A literature review was performed through PubMed from 1980 through 2014 using the search terms ‘cosmetic’, ‘ocular’, ‘conjunctivectomy’, ‘regional conjunctivectomy’, ‘I-BRITE’, ‘eye-whitening’, ‘scleritis’, ‘necrotizing scleritis’, ‘anterior uveitis’, ‘mitomycin C’, ‘5-fluorouracil’, and ‘bevacizumab’, along with associated cross-referencing from relevant articles. Results Examination of the patient revealed bilateral necrotizing scleritis within the nasal region of both eyes. Calcified plaques were also present within the areas of scleromalacia, along with epithelial defects demonstrated with fluorescein staining. Although evidence of previous intraocular inflammation was apparent within the left eye, there were no active signs of inflammation evident within either eye on initial presentation. Complication rates reported in the literature include: scleral thinning (1.8%), calcific plaque formation (2.9%), fibrovascular proliferation (13%), diplopia (1.2%), elevation of intraocular pressure (4.2%), and recurrence of conjunctival hyperemia (2.1%). Conclusion Cosmetic ocular whitening procedures have an attendant high complication rate, and have been associated with several adverse postoperative complications, which have in turn generated several reservations regarding the veritable benefit of the procedure. Many postsurgical complications may demonstrate delayed apparition, varying from several months to several years after primary surgical intervention as in the case reported here. PMID:25784790

Delayed manifestation of bilateral scleral thinning after I-BRITE(®) procedure and review of literature for cosmetic eye-whitening procedures.

PubMed

Moshirfar, Majid; McCaughey, Michael V; Fenzl, Carlton R; Santiago-Caban, Luis; Kramer, Gregory D; Mamalis, Nick

2015-01-01

To report a case of delayed-onset bilateral scleral thinning and calcium deposition following a cosmetic ocular-whitening procedure (I-BRITE(®)). A 33-year-old male patient with a history of right-sided ptosis repair and left-sided anterior uveitis had previously undergone bilateral I-BRITE treatment for chronic conjunctival hyperemia. Four years after the procedure, the patient was referred to our institution with bilateral scleral thinning and overlying calcific depositions. A literature review was performed through PubMed from 1980 through 2014 using the search terms 'cosmetic', 'ocular', 'conjunctivectomy', 'regional conjunctivectomy', 'I-BRITE', 'eye-whitening', 'scleritis', 'necrotizing scleritis', 'anterior uveitis', 'mitomycin C', '5-fluorouracil', and 'bevacizumab', along with associated cross-referencing from relevant articles. Examination of the patient revealed bilateral necrotizing scleritis within the nasal region of both eyes. Calcified plaques were also present within the areas of scleromalacia, along with epithelial defects demonstrated with fluorescein staining. Although evidence of previous intraocular inflammation was apparent within the left eye, there were no active signs of inflammation evident within either eye on initial presentation. Complication rates reported in the literature include: scleral thinning (1.8%), calcific plaque formation (2.9%), fibrovascular proliferation (13%), diplopia (1.2%), elevation of intraocular pressure (4.2%), and recurrence of conjunctival hyperemia (2.1%). Cosmetic ocular whitening procedures have an attendant high complication rate, and have been associated with several adverse postoperative complications, which have in turn generated several reservations regarding the veritable benefit of the procedure. Many postsurgical complications may demonstrate delayed apparition, varying from several months to several years after primary surgical intervention as in the case reported here.

Visualization Improves Supraclavicular Access to the Subclavian Vein in a Mixed Reality Simulator.

PubMed

Sappenfield, Joshua Warren; Smith, William Brit; Cooper, Lou Ann; Lizdas, David; Gonsalves, Drew B; Gravenstein, Nikolaus; Lampotang, Samsun; Robinson, Albert R

2018-07-01

We investigated whether visual augmentation (3D, real-time, color visualization) of a procedural simulator improved performance during training in the supraclavicular approach to the subclavian vein, not as widely known or used as its infraclavicular counterpart. To train anesthesiology residents to access a central vein, a mixed reality simulator with emulated ultrasound imaging was created using an anatomically authentic, 3D-printed, physical mannequin based on a computed tomographic scan of an actual human. The simulator has a corresponding 3D virtual model of the neck and upper chest anatomy. Hand-held instruments such as a needle, an ultrasound probe, and a virtual camera controller are directly manipulated by the trainee and tracked and recorded with submillimeter resolution via miniature, 6 degrees of freedom magnetic sensors. After Institutional Review Board approval, 69 anesthesiology residents and faculty were enrolled and received scripted instructions on how to perform subclavian venous access using the supraclavicular approach based on anatomic landmarks. The volunteers were randomized into 2 cohorts. The first used real-time 3D visualization concurrently with trial 1, but not during trial 2. The second did not use real-time 3D visualization concurrently with trial 1 or 2. However, after trial 2, they observed a 3D visualization playback of trial 2 before performing trial 3 without visualization. An automated scoring system based on time, success, and errors/complications generated objective performance scores. Nonparametric statistical methods were used to compare the scores between subsequent trials, differences between groups (real-time visualization versus no visualization versus delayed visualization), and improvement in scores between trials within groups. Although the real-time visualization group demonstrated significantly better performance than the delayed visualization group on trial 1 (P = .01), there was no difference in gain scores, between performance on the first trial and performance on the final trial, that were dependent on group (P = .13). In the delayed visualization group, the difference in performance between trial 1 and trial 2 was not significant (P = .09); reviewing performance on trial 2 before trial 3 resulted in improved performance when compared to trial 1 (P < .0001). There was no significant difference in median scores (P = .13) between the real-time visualization and delayed visualization groups for the last trial after both groups had received visualization. Participants reported a significant improvement in confidence in performing supraclavicular access to the subclavian vein. Standard deviations of scores, a measure of performance variability, decreased in the delayed visualization group after viewing the visualization. Real-time visual augmentation (3D visualization) in the mixed reality simulator improved performance during supraclavicular access to the subclavian vein. No difference was seen in the final trial of the group that received real-time visualization compared to the group that had delayed visualization playback of their prior attempt. Training with the mixed reality simulator improved participant confidence in performing an unfamiliar technique.

Comparison of delay enhancement mechanisms for SBS-based slow light systems.

PubMed

Schneider, Thomas; Henker, Ronny; Lauterbach, Kai-Uwe; Junker, Markus

2007-07-23

We compare two simple mechanisms for the enhancement of the time delay in slow light systems. Both are based on the superposition of the Brillouin gain with additional loss. As we will show in theory and experiment if two losses are placed at the wings of a SBS gain, contrary to other methods, the loss power increases the time delay. This leads to higher delay times at lower optical powers and to an increase of the zero gain delay of more than 50%. With this method we achieved a time delay of more than 120ns for pulses with a temporal width of 30ns. To the best of our knowledge, this is the highest time delay in just one fiber spool. Beside the enhancement of the time delay the method could have the potential to decrease the pulse distortions for high bit rate signals.

Impact of Partial Time Delay on Temporal Dynamics of Watts-Strogatz Small-World Neuronal Networks

NASA Astrophysics Data System (ADS)

Yan, Hao; Sun, Xiaojuan

2017-06-01

In this paper, we mainly discuss effects of partial time delay on temporal dynamics of Watts-Strogatz (WS) small-world neuronal networks by controlling two parameters. One is the time delay τ and the other is the probability of partial time delay pdelay. Temporal dynamics of WS small-world neuronal networks are discussed with the aid of temporal coherence and mean firing rate. With the obtained simulation results, it is revealed that for small time delay τ, the probability pdelay could weaken temporal coherence and increase mean firing rate of neuronal networks, which indicates that it could improve neuronal firings of the neuronal networks while destroying firing regularity. For large time delay τ, temporal coherence and mean firing rate do not have great changes with respect to pdelay. Time delay τ always has great influence on both temporal coherence and mean firing rate no matter what is the value of pdelay. Moreover, with the analysis of spike trains and histograms of interspike intervals of neurons inside neuronal networks, it is found that the effects of partial time delays on temporal coherence and mean firing rate could be the result of locking between the period of neuronal firing activities and the value of time delay τ. In brief, partial time delay could have great influence on temporal dynamics of the neuronal networks.

Piloted simulator study of allowable time delay in pitch flight control system of a transport airplane with negative static stability

NASA Technical Reports Server (NTRS)

Grantham, William D.; Smith, Paul M.; Person, Lee H., Jr.; Meyer, Robert T.; Tingas, Stephen A.

1987-01-01

A piloted simulation study was conducted to determine the permissible time delay in the flight control system of a 10-percent statically unstable transport airplane during cruise flight conditions. The math model used for the simulation was a derivative Lockheed L-1011 wide-body jet transport. Data were collected and analyzed from a total of 137 cruising flights in both calm- and turbulent-air conditions. Results of this piloted simulation study verify previous findings that show present military specifications for allowable control-system time delay may be too stringent when applied to transport-size airplanes. Also, the degree of handling-qualities degradation due to time delay is shown to be strongly dependent on the source of the time delay in an advanced flight control system. Maximum allowable time delay for each source of time delay in the control system, in addition to a less stringent overall maximum level of time delay, should be considered for large aircraft. Preliminary results also suggest that adverse effects of control-system time delay may be at least partially offset by variations in control gearing. It is recommended that the data base include different airplane baselines, control systems, and piloting tasks with many pilots participating, so that a reasonable set of limits for control-system time delay can be established to replace the military specification limits currently being used.

Operating in an eczematous surgical field: don't be rash, delay surgery to avoid infective complications.

PubMed

Beckett, K S; Gault, D T

2006-01-01

Prominent ear correction is a common operation. Complication as a result of infection has been quoted at between 3% and 5% [Calder JC, Nasaan A. Morbidity of otoplasty: a review of 562 consecutive cases. Br J Plast Surg 1994;47:170-4 and Jeffery SLA. Complications following correction of prominent ears: an audit review of 122 cases. Br J Plast Surg 1999;52:588-90.]. We present two cases referred for ear reconstruction following catastrophic post-operative infection at the time of pinnaplasty, leaving each patient with significant helical rim deformities. Both patients displayed evidence of active post-auricular eczema at the time of their primary surgery. Dermatological research has highlighted the increased colonisation of Staphylococcus aureus in particular within areas of atopic eczema in comparison to normal skin. We advise delaying ear surgery in the presence of a rash in view of the potentially devastating complications that may result. This approach may be extended to all cutaneous surgery where treatment of the rash is advocated prior to embarking on an elective surgical procedure.

A model-free method for mass spectrometer response correction. [for oxygen consumption and cardiac output calculation

NASA Technical Reports Server (NTRS)

Shykoff, Barbara E.; Swanson, Harvey T.

1987-01-01

A new method for correction of mass spectrometer output signals is described. Response-time distortion is reduced independently of any model of mass spectrometer behavior. The delay of the system is found first from the cross-correlation function of a step change and its response. A two-sided time-domain digital correction filter (deconvolution filter) is generated next from the same step response data using a regression procedure. Other data are corrected using the filter and delay. The mean squared error between a step response and a step is reduced considerably more after the use of a deconvolution filter than after the application of a second-order model correction. O2 consumption and CO2 production values calculated from data corrupted by a simulated dynamic process return to near the uncorrupted values after correction. Although a clean step response or the ensemble average of several responses contaminated with noise is needed for the generation of the filter, random noise of magnitude not above 0.5 percent added to the response to be corrected does not impair the correction severely.

Delay Discounting Rates Are Temporally Stable in an Equivalent Present Value Procedure Using Theoretical and Area under the Curve Analyses

ERIC Educational Resources Information Center

Harrison, Justin; McKay, Ryan

2012-01-01

Temporal discounting rates have become a popular dependent variable in social science research. While choice procedures are commonly employed to measure discounting rates, equivalent present value (EPV) procedures may be more sensitive to experimental manipulation. However, their use has been impeded by the absence of test-retest reliability data.…

Delay discounting of qualitatively different reinforcers in rats.

PubMed

Calvert, Amanda L; Green, Leonard; Myerson, Joel

2010-03-01

Humans discount larger delayed rewards less steeply than smaller rewards, whereas no such magnitude effect has been observed in rats (and pigeons). It remains possible that rats' discounting is sensitive to differences in the quality of the delayed reinforcer even though it is not sensitive to amount. To evaluate this possibility, Experiment 1 examined discounting of qualitatively different food reinforcers: highly preferred versus nonpreferred food pellets. Similarly, Experiment 2 examined discounting of highly preferred versus nonpreferred liquid reinforcers. In both experiments, an adjusting-amount procedure was used to determine the amount of immediate reinforcer that was judged to be of equal subjective value to the delayed reinforcer. The amount and quality of the delayed reinforcer were varied across conditions. Discounting was well described by a hyperbolic function, but no systematic effects of the quantity or the quality of the delayed reinforcer were observed.

Femtosecond noncollinear SFG dynamics in autocorrelator setup at low level of photons

NASA Astrophysics Data System (ADS)

Tenishev, Vladimir P.; Persson, A.; Larsson, J.

2004-06-01

We report here the characteristics of noncollinear sum frequency generation in nonlinear KDP crystals by ultrashort (80 fsec) IR pulses irradiated by the intense Ti:Sapphire laser and their behavior in single shot auto-crosscorrelator (ACC) configuration. In particular we study the case where one of the beams is very weak. Our aim is to develop a procedure to provide delay time signal between light pulses for time resolved pump probe experiments based on the extraction of the phase-matched SHG spatial distribution by means of pulse shape analysis technique. We intend to apply these results to synchronize a weak short-pulse source and an intense Ti:Sapphire laser and to measure the pulse time jitter between them.

Simplified filtered Smith predictor for MIMO processes with multiple time delays.

PubMed

Santos, Tito L M; Torrico, Bismark C; Normey-Rico, Julio E

2016-11-01

This paper proposes a simplified tuning strategy for the multivariable filtered Smith predictor. It is shown that offset-free control can be achieved with step references and disturbances regardless of the poles of the primary controller, i.e., integral action is not explicitly required. This strategy reduces the number of design parameters and simplifies tuning procedure because the implicit integrative poles are not considered for design purposes. The simplified approach can be used to design continuous-time or discrete-time controllers. Three case studies are used to illustrate the advantages of the proposed strategy if compared with the standard approach, which is based on the explicit integrative action. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Artificial time constraints on the Iowa Gambling Task: the effects on behavioural performance and subjective experience.

PubMed

Bowman, Caroline H; Evans, Cathryn E Y; Turnbull, Oliver H

2005-02-01

In the last decade, the Iowa Gambling Task (IGT) has become a widely employed neuropsychological research instrument for the investigation of executive function. The task has been employed in a wide range of formats, from 'manual' procedures to more recently introduced computerised versions. Computer-based formats often require that responses on the task should be artificially delayed by a number of seconds between trials to collect skin-conductance data. Participants, however, may become frustrated when they want to select from a particular deck in the time-limited versions--so that an unintended emotional experience of frustration might well disrupt a task presumed to be reliant on emotion-based learning. We investigated the effect of the various types of Iowa Gambling Task format on performance, using three types of task: the classic manual administration, with no time limitations; a computerised administration with a 6-s enforced delay; and a control computerised version which had no time constraints. We also evaluated the subjective experience of participants on each task. There were no significant differences in performance, between formats, in behavioural terms. Subjective experience measures on the task also showed consistent effects across all three formats-with substantial, and rapidly developing, awareness of which decks were 'good' and 'bad.'

Chronic relapsing pancreatitis in a child. Use of the Puestow procedure to achieve ductal drainage.

PubMed

Duncan, N D; McDonald, A; James, M; Brown, B; Mitchell, D I

2000-09-01

A case of chronic relapsing pancreatitis presenting in an 8-year-old African Jamaican girl is outlined. Aggressive supportive management failed to control pain and vomiting. The Puestow Procedure effectively procedure aborted these symptoms. The use of the Puestow procedure should not be inordinately delayed in chronic relapsing pancreatitis if symptoms persist, since it may not only control pain but also halt declining pancreatic function.

The facilitative effects of incidental teaching on preposition use by autistic children.

PubMed Central

McGee, G G; Krantz, P J; McClannahan, L E

1985-01-01

In a comparison of incidental teaching and traditional training procedures, three language-delayed autistic children were taught expressive use of prepositions to describe the location of preferred edibles and toys. Traditional highly structured training and incidental teaching procedures were used in a classroom setting, and generalization was assessed during free-play sessions. Results clearly indicate that incidental teaching promoted greater generalization and more spontaneous use of prepositions. These findings have important implications for language programming and teacher training, suggesting that incidental teaching should be included as a standard component of language development curricula for autistic and other developmentally delayed children. PMID:3997695

76 FR 68734 - Taking and Importing Marine Mammals: Taking Marine Mammals Incidental to Navy Training Exercises...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-07

... marine mammal is likely to travel during the time associated with the TDFD's time delay, and that... Navy provided the approximate distance that an animal would typically travel within a given time-delay... Speed and Length of Time-Delay Potential distance Species group Swim speed Time-delay traveled Delphinid...

Patient Evaluation and Preparation in Vascular and Interventional Radiology: What Every Interventional Radiologist Should Know (Part 2: Patient Preparation and Medications)

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

Taslakian, Bedros, E-mail: btaslakian@gmail.com; Sebaaly, Mikhael Georges, E-mail: ms246@aub.edu.lb; Al-Kutoubi, Aghiad, E-mail: mk00@aub.edu.lb

2016-04-15

Performing an interventional procedure imposes a commitment on interventional radiologists to conduct the initial patient assessment, determine the best course of therapy, and provide long-term care. Patient care before and after an interventional procedure, identification, and management of early and delayed complications of various procedures are equal in importance to the procedure itself. In this second part, we complete the comprehensive, methodical review of pre-procedural care and patient preparation before vascular and interventional radiology procedures.

Patient Evaluation and Preparation in Vascular and Interventional Radiology: What Every Interventional Radiologist Should Know (Part 2: Patient Preparation and Medications).

PubMed

Taslakian, Bedros; Sebaaly, Mikhael Georges; Al-Kutoubi, Aghiad

2016-04-01

Performing an interventional procedure imposes a commitment on interventional radiologists to conduct the initial patient assessment, determine the best course of therapy, and provide long-term care. Patient care before and after an interventional procedure, identification, and management of early and delayed complications of various procedures are equal in importance to the procedure itself. In this second part, we complete the comprehensive, methodical review of pre-procedural care and patient preparation before vascular and interventional radiology procedures.

Development of an Information Model for Kidney Transplant Wait List.

PubMed

Bircan, Hüseyin Yüce; Özçelik, Ümit; Uysal, Nida; Demirağ, Alp; Haberal, Mehmet

2015-11-01

Deceased-donor kidney transplant is unique among surgical procedures that are an urgent procedure performed in an elective population. It has not been possible to accurately determine when a given patient will be called for transplant. Patients on the active transplant list can be called for a transplant at any time. As a result, every effort must be made to optimize their health according to best practices and published clinical practice guidelines. Once the patient is placed on the transplant wait list after undergoing an initial extensive evaluation, continued surveillance is required. Therefore, we developed a kidney transplant wait list surveillance software program that alerts organ transplant coordinator on time regarding which patients need a work-up. The new designed software has a database of our waiting patients with their completed and pending controls. The software also has built-in functions to warn the responsible staff with an E-mail. If one of the controls of a recipient delayed, the software sends an automated E-mail to the staff regarding the patients delayed controls. The software is a Web application that works on any platform with a Web browser and Internet connection and allows access by multiple users. The software has been developed with NET platform. The database is SQL server. The software has the following functions: patient communication info, search, alert list, alert E-mail, control entry, and system management. As of January 2014, a total of 21 000 patients were registered on the National Kidney Transplant wait list in Turkey and the kidney transplant wait list had been expanding by 2000 to 3000 patients each year. Therefore computerized wait list programs are crucial to help to transplant centers to keep their patients up-to-date on time.

Primary versus delayed repair for bile duct injuries sustained during cholecystectomy: results of a survey of the Association Francaise de Chirurgie

PubMed Central

Iannelli, Antonio; Paineau, Jacques; Hamy, Antoine; Schneck, Anne-Sophie; Schaaf, Caroline; Gugenheim, Jean

2013-01-01

Background Bile duct injuries (BDIs) sustained during a cholecystectomy still remain a major surgical problem, and it is still not clear whether the injury should be repaired immediately or a delayed repair is preferred. Methods A retrospective national French survey was conducted to compare the results of immediate (at time of cholecystectomy), early (within 45 days after a cholecystectomy) and late (beyond 45 days after a cholecystectomy) surgical repair for BDI sustained during a cholecystectomy. Results Forty-seven surgical centres provided 640 cases of bile duct injury sustained during a cholecystectomy of which 543 were analysed for the purpose of the present study. The timing of repair was immediate in 194 cases (35.7%), early in 216 cases (39.8%) and late in 133 cases (24.5%). The type of repair was a suture repair in 157 cases (81%), and a bilio-digestive reconstruction in 37 cases (19%) for immediate repair; a suture repair in 119 cases (55.1%) and a bilio-digestive anastomosis in 96 cases (44.9%) for the early repair; and a bilio-digestive reconstruction in 129 cases (97%) and a suture repair in 4 cases (3%) for late repair. A second procedure was required in 110 cases (56.7%) for immediate repair, 80 cases (40.7%) for early repair (P < 0.05) and in 9 cases (6.8%) for late repair (P < 0.001). Conclusion The timing of surgical repair for a bile duct injury sustained during a cholecystectomy influences significantly the rate of a second procedure and a late repair should be preferred option. PMID:23458568

Contextual Specificity of Extinction of Delay but Not Trace Eyeblink Conditioning in Humans

ERIC Educational Resources Information Center

Grillon, Christian; Alvarez, Ruben P.; Johnson, Linda; Chavis, Chanen

2008-01-01

Renewal of an extinguished conditioned response has been demonstrated in humans and in animals using various types of procedures, except renewal of motor learning such as eyeblink conditioning. We tested renewal of delay and trace eyeblink conditioning in a virtual environment in an ABA design. Following acquisition in one context (A, e.g., an…

Relations among Acute and Chronic Nicotine Administration, Short-Term Memory, and Tactics of Data Analysis

ERIC Educational Resources Information Center

Kangas, Brian D.; Branch, Marc N.

2012-01-01

Emerging evidence suggests that nicotine may enhance short-term memory. Some of this evidence comes from nonhuman primate research using a procedure called delayed matching-to-sample, wherein the monkey is trained to select a comparison stimulus that matches some physical property of a previously presented sample stimulus. Delays between sample…

The Use of Picture Prompts and Prompt Delay to Teach Receptive Labeling

ERIC Educational Resources Information Center

Vedora, Joseph; Barry, Tiffany

2016-01-01

The current study extended research on picture prompts by using them with a progressive prompt delay to teach receptive labeling of pictures to 2 teenagers with autism. The procedure differed from prior research because the auditory stimulus was not presented or was presented only once during the picture-prompt condition. The results indicated…

A 20 Year Review of Punishment and Alternative Methods to Treat Problem Behaviors in Developmentally Delayed Persons.

ERIC Educational Resources Information Center

Matson, Johnny L.; Taras, Marie E.

1989-01-01

Studies assessing treatments for severe behavior problems of developmentally delayed persons were reviewed. Procedures used in the 382 studies, published from 1967-1987, were analyzed in terms of problem behaviors, side effects, and treatment methods. Also examined were number of studies reported yearly, maintenance and generalization of effects,…

Time delay can facilitate coherence in self-driven interacting-particle systems

NASA Astrophysics Data System (ADS)

Sun, Yongzheng; Lin, Wei; Erban, Radek

2014-12-01

Directional switching in a self-propelled particle model with delayed interactions is investigated. It is shown that the average switching time is an increasing function of time delay. The presented results are applied to studying collective animal behavior. It is argued that self-propelled particle models with time delays can explain the state-dependent diffusion coefficient measured in experiments with locust groups. The theory is further generalized to heterogeneous groups where each individual can respond to its environment with a different time delay.

Performance Analysis of Different Backoff Algorithms for WBAN-Based Emerging Sensor Networks

PubMed Central

Khan, Pervez; Ullah, Niamat; Ali, Farman; Ullah, Sana; Hong, Youn-Sik; Lee, Ki-Young; Kim, Hoon

2017-01-01

The Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) procedure of IEEE 802.15.6 Medium Access Control (MAC) protocols for the Wireless Body Area Network (WBAN) use an Alternative Binary Exponential Backoff (ABEB) procedure. The backoff algorithm plays an important role to avoid collision in wireless networks. The Binary Exponential Backoff (BEB) algorithm used in different standards does not obtain the optimum performance due to enormous Contention Window (CW) gaps induced from packet collisions. Therefore, The IEEE 802.15.6 CSMA/CA has developed the ABEB procedure to avoid the large CW gaps upon each collision. However, the ABEB algorithm may lead to a high collision rate (as the CW size is incremented on every alternative collision) and poor utilization of the channel due to the gap between the subsequent CW. To minimize the gap between subsequent CW sizes, we adopted the Prioritized Fibonacci Backoff (PFB) procedure. This procedure leads to a smooth and gradual increase in the CW size, after each collision, which eventually decreases the waiting time, and the contending node can access the channel promptly with little delay; while ABEB leads to irregular and fluctuated CW values, which eventually increase collision and waiting time before a re-transmission attempt. We analytically approach this problem by employing a Markov chain to design the PFB scheme for the CSMA/CA procedure of the IEEE 80.15.6 standard. The performance of the PFB algorithm is compared against the ABEB function of WBAN CSMA/CA. The results show that the PFB procedure adopted for IEEE 802.15.6 CSMA/CA outperforms the ABEB procedure. PMID:28257112

Assessment of hemodynamic load components affecting optimization of cardiac resynchronization therapy by lumped parameter mode.

PubMed

Xu, Ke; Butlin, Mark; Avolio, Alberto P

2012-01-01

Timing of biventricular pacing devices employed in cardiac resynchronization therapy (CRT) is a critical determinant of efficacy of the procedure. Optimization is done by maximizing function in terms of arterial pressure (BP) or cardiac output (CO). However, BP and CO are also determined by the hemodynamic load of the pulmonary and systemic vasculature. This study aims to use a lumped parameter circulatory model to assess the influence of the arterial load on the atrio-ventricular (AV) and inter-ventricular (VV) delay for optimal CRT performance.

An evaluation of two methods for increasing self-initiated verbalizations in autistic children.

PubMed Central

Matson, J L; Sevin, J A; Box, M L; Francis, K L; Sevin, B M

1993-01-01

Three children with autism and mental retardation were treated for deficits in self-initiated speech. A novel treatment package employing visual cue fading was compared with a graduated time-delay procedure previously shown to be effective for increasing self-initiated language. Both treatments included training multiple self-initiated verbalizations using multiple therapists and settings. Both treatments were effective, with no differences in measures of acquisition of target phrases, maintenance of behavioral gains, acquisition with additional therapists and settings, and social validity. PMID:8407687

Delay banking for air traffic management

NASA Technical Reports Server (NTRS)

Green, Steven M. (Inventor)

2007-01-01

A method and associated system for time delay banking for aircraft arrival time, aircraft departure time and/or en route flight position. The delay credit value for a given flight may decrease with passage of time and may be transferred to or traded with other flights having the same or a different user (airline owner or operator). The delay credit value for a given aircraft flight depends upon an initial delay credit value, which is determined by a central system and depends upon one or more other flight characteristics. Optionally, the delay credit value decreases with passage of time. Optionally, a transaction cost is assessed against a delay credit value that is used on behalf of another flight with the same user or is traded with a different user.

General relation between the group delay and dwell time in multicomponent electron systems

NASA Astrophysics Data System (ADS)

Zhai, Feng; Lu, Junqiang

2016-10-01

For multicomponent electron scattering states, we derive a general relation between the Wigner group delay and the Bohmian dwell time. It is found that the definition of group delay should account for the phase of the spinor wave functions of propagating modes. The difference between the group delay and dwell time comes from both the interference delay and the decaying modes. For barrier tunneling of helical electrons on a surface of topological insulators, our calculations including the trigonal-warping term show that the decaying modes can contribute greatly to the group delay. The derived relation between the group delay and the dwell time is helpful to unify the two definitions of tunneling time in a quite general situation.

CAN LARGE TIME DELAYS OBSERVED IN LIGHT CURVES OF CORONAL LOOPS BE EXPLAINED IN IMPULSIVE HEATING?

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

Lionello, Roberto; Linker, Jon A.; Mikić, Zoran

The light curves of solar coronal loops often peak first in channels associated with higher temperatures and then in those associated with lower temperatures. The delay times between the different narrowband EUV channels have been measured for many individual loops and recently for every pixel of an active region observation. The time delays between channels for an active region exhibit a wide range of values. The maximum time delay in each channel pair can be quite large, i.e., >5000 s. These large time delays make-up 3%–26% (depending on the channel pair) of the pixels where a trustworthy, positive time delaymore » is measured. It has been suggested that these time delays can be explained by simple impulsive heating, i.e., a short burst of energy that heats the plasma to a high temperature, after which the plasma is allowed to cool through radiation and conduction back to its original state. In this paper, we investigate whether the largest observed time delays can be explained by this hypothesis by simulating a series of coronal loops with different heating rates, loop lengths, abundances, and geometries to determine the range of expected time delays between a set of four EUV channels. We find that impulsive heating cannot address the largest time delays observed in two of the channel pairs and that the majority of the large time delays can only be explained by long, expanding loops with photospheric abundances. Additional observations may rule out these simulations as an explanation for the long time delays. We suggest that either the time delays found in this manner may not be representative of real loop evolution, or that the impulsive heating and cooling scenario may be too simple to explain the observations, and other potential heating scenarios must be explored.« less

Cognitive person variables in the delay of gratification of older children at risk.

PubMed

Rodriguez, M L; Mischel, W; Shoda, Y

1989-08-01

The components of self-regulation were analyzed, extending the self-imposed delay of gratification paradigm to older children with social adjustment problems. Delay behavior was related to a network of conceptually relevant cognitive person variables, consisting of attention deployment strategies during delay, knowledge of delay rules, and intelligence. A positive relationship was demonstrated between concurrent indexes of intelligence, attention deployment, and actual delay time. Moreover, attention deployment, measured as an individual differences variable during the delay process, had a direct, positive effect on delay behavior. Specifically, as the duration of delay and the frustration of the situation increased, children who spent a higher proportion of the time distracting themselves from the tempting elements of the delay situation were able to delay longer. The effect of attention deployment on delay behavior was significant even when age, intelligence, and delay rule knowledge were controlled. Likewise, delay rule knowledge significantly predicted delay time, even when age, attention deployment, and intelligence were controlled.

[Tobacco and plastic surgery: An absolute contraindication?

PubMed

Matusiak, C; De Runz, A; Maschino, H; Brix, M; Simon, E; Claudot, F

2017-08-01

Smoking increases perioperative risk regarding wound healing, infection rate and failure of microsurgical procedures. There is no present consensus about plastic and aesthetic surgical indications concerning smoking patients. The aim of our study is to analyze French plastic surgeons practices concerning smokers. A questionnaire was send by e-mail to French plastic surgeons in order to evaluate their own operative indications: patient information about smoking dangers, pre- and postoperative delay of smoking cessation, type of intervention carried out, smoking cessation supports, use of screening test and smoking limit associated to surgery refusing were studied. Statistical tests were used to compare results according to practitioner activity (liberal or public), own smoking habits and time of installation. In 148 questionnaires, only one surgeon did not explain smoking risk. Of the surgeons, 49.3% proposed smoking-cessation supports, more frequently with public practice (P=0.019). In total, 85.4% of surgeons did not use screening tests. Years of installation affected operative indication with smoking patients (P=0.02). Pre- and postoperative smoking cessation delay were on average respectively 4 and 3 weeks in accordance with literature. Potential improvements could be proposed to smoking patients' care: smoking cessation assistance, screening tests, absolute contraindication of some procedures or level of consumption to determine. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia.

PubMed

Glavatskiy, K S

2015-10-28

Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called "mirror-image" systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval.

[Injuries to the duodenum and pancreas in 42 operated cases].

PubMed

Kiss, L; Remescu, A

2001-01-01

42 consecutive patients who sustained injuries to the duodenum or/and pancreas were admitted to our hospital. Over a twenty year period 32 blunt injuries and 10 penetrating injuries were encountered. Penetrating injuries were always suspected and treated by time: following blunt injury diagnostic delay was encountered in 14 patients and insufficient surgical procedure because of intra-operative misinterpretation in 2 patients. Most of the patients had associated intra-abdominal organ injuries. Adjusts to diagnosis such as abdominal roentgenograms, serum amylase levels and gastroduodenography was not helpful. CT scan and ultrasound allowed to confirm the suspected diagnosis in 3 cases only. Intraoperative diagnosis was also challenging. Complete mobilization of the strictures surrounding the duodenum and the pancreas to provide entire exposure was necessary in 12 patients treated first in a peripheral hospital, diagnosis of the injury have been missed at first laparotomy and reoperation was necessary in all of them. Suture closure of the duodenum and drainage of the pancreatic region wee the most common reparative techniques used. More complicated procedures with pancreatic and/or duodenal resection were performed in 12 patients. Overall mortality in patients surviving more than 24 hours was 14%. Suture live dehiscence after delayed operation (4) and 2 deaths due to brain injury.

Firing patterns transition and desynchronization induced by time delay in neural networks

NASA Astrophysics Data System (ADS)

Huang, Shoufang; Zhang, Jiqian; Wang, Maosheng; Hu, Chin-Kun

2018-06-01

We used the Hindmarsh-Rose (HR) model (Hindmarsh and Rose, 1984) to study the effect of time delay on the transition of firing behaviors and desynchronization in neural networks. As time delay is increased, neural networks exhibit diversity of firing behaviors, including regular spiking or bursting and firing patterns transitions (FPTs). Meanwhile, the desynchronization of firing and unstable bursting with decreasing amplitude in neural system, are also increasingly enhanced with the increase of time delay. Furthermore, we also studied the effect of coupling strength and network randomness on these phenomena. Our results imply that time delays can induce transition and desynchronization of firing behaviors in neural networks. These findings provide new insight into the role of time delay in the firing activities of neural networks, and can help to better understand the firing phenomena in complex systems of neural networks. A possible mechanism in brain that can cause the increase of time delay is discussed.

Effects of N-methyl-D-aspartate receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure

PubMed Central

Yates, Justin R; Gunkel, Benjamin T; Rogers, Katherine K; Hughes, Mallory N; Prior, Nicholas A

2016-01-01

Rationale The N-methyl-D-aspartate (NMDA) receptor has been recently identified as an important mediator of impulsive choice, as assessed in delay discounting. Although discounting is independently influenced by sensitivity to reinforcer magnitude and delayed reinforcement, few studies have examined how NMDA receptor ligands differentially affect these parameters. Objectives The current study examined the effects of various NMDA receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure. Methods Following behavioral training, rats received treatments of the following NMDA receptor ligands: the uncompetitive antagonists ketamine (0, 1.0, 5.0, or 10.0 mg/kg; i.p.), MK-801 (0, 0.003, 0.01, or 0.03 mg/kg; s.c.), and memantine (0, 2.5, 5.0, or 10.0 mg/kg; i.p.), the competitive antagonist CGS 19755 (0, 5.0, 10.0, or 20.0 mg/kg; s.c.), the non-competitive NR2B subunit-selective antagonist ifenprodil (0, 1.0, 3.0, or 10.0 mg/kg; i.p), and the partial agonist D-cycloserine (0, 3.25, 15.0, or 30.0 mg/kg; s.c.). Results When an exponential model was used to describe discounting, CGS 19755 (5.0 mg/kg) increased impulsive choice without altering sensitivity to reinforcer magnitude. Conversely, ketamine (10.0 mg/kg), memantine (5.0 mg/kg), and ifenprodil (10.0 mg/kg) decreased sensitivity to reinforcer magnitude without altering impulsive choice. MK-801 and D-cycloserine did not alter delay-discounting performance, although two-way ANOVA analyses indicated D-cycloserine (15.0 mg/kg) decreased impulsive choice. Conclusions The behavioral changes observed in delay discounting following administration of NMDA receptor antagonists do not always reflect an alteration in impulsive choice. These results emphasize the utility in employing quantitative methods to assess drug effects in delay discounting. PMID:27837332

Delay time in a single barrier for a movable quantum shutter

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

Hernandez, Alberto

2010-05-15

The transient solution and delay time for a {delta} potential scatterer with a movable quantum shutter is calculated by solving analytically the time-dependent Schroedinger equation. The delay time is analyzed as a function of the distance between the shutter and the potential barrier and also as a function of the distance between the potential barrier and the detector. In both cases, it is found that the delay time exhibits a dynamical behavior and that it tends to a saturation value {Delta}t{sub sat} in the limit of very short distances, which represents the maximum delay produced by the potential barrier nearmore » the interaction region. The phase time {tau}{sub {theta},} on the other hand, is not an appropriate time scale for measuring the time delay near the interaction region, except if the shutter is moved far away from the potential. The role played by the antibound state of the system on the behavior of the delay time is also discussed.« less

Efficiency of endoscopy units can be improved with use of discrete event simulation modeling.

PubMed

Sauer, Bryan G; Singh, Kanwar P; Wagner, Barry L; Vanden Hoek, Matthew S; Twilley, Katherine; Cohn, Steven M; Shami, Vanessa M; Wang, Andrew Y

2016-11-01

Background and study aims: The projected increased demand for health services obligates healthcare organizations to operate efficiently. Discrete event simulation (DES) is a modeling method that allows for optimization of systems through virtual testing of different configurations before implementation. The objective of this study was to identify strategies to improve the daily efficiencies of an endoscopy center with the use of DES. Methods: We built a DES model of a five procedure room endoscopy unit at a tertiary-care university medical center. After validating the baseline model, we tested alternate configurations to run the endoscopy suite and evaluated outcomes associated with each change. The main outcome measures included adequate number of preparation and recovery rooms, blocked inflow, delay times, blocked outflows, and patient cycle time. Results: Based on a sensitivity analysis, the adequate number of preparation rooms is eight and recovery rooms is nine for a five procedure room unit (total 3.4 preparation and recovery rooms per procedure room). Simple changes to procedure scheduling and patient arrival times led to a modest improvement in efficiency. Increasing the preparation/recovery rooms based on the sensitivity analysis led to significant improvements in efficiency. Conclusions: By applying tools such as DES, we can model changes in an environment with complex interactions and find ways to improve the medical care we provide. DES is applicable to any endoscopy unit and would be particularly valuable to those who are trying to improve on the efficiency of care and patient experience.

Tube thoracostomy training with a medical simulator is associated with faster, more successful performance of the procedure

PubMed Central

Chung, Tae Nyoung; Kim, Sun Wook; You, Je Sung; Chung, Hyun Soo

2016-01-01

Objective Tube thoracostomy (TT) is a commonly performed intensive care procedure. Simulator training may be a good alternative method for TT training, compared with conventional methods such as apprenticeship and animal skills laboratory. However, there is insufficient evidence supporting use of a simulator. The aim of this study is to determine whether training with medical simulator is associated with faster TT process, compared to conventional training without simulator. Methods This is a simulation study. Eligible participants were emergency medicine residents with very few (≤3 times) TT experience. Participants were randomized to two groups: the conventional training group, and the simulator training group. While the simulator training group used the simulator to train TT, the conventional training group watched the instructor performing TT on a cadaver. After training, all participants performed a TT on a cadaver. The performance quality was measured as correct placement and time delay. Subjects were graded if they had difficulty on process. Results Estimated median procedure time was 228 seconds in the conventional training group and 75 seconds in the simulator training group, with statistical significance (P=0.040). The difficulty grading did not show any significant difference among groups (overall performance scale, 2 vs. 3; P=0.094). Conclusion Tube thoracostomy training with a medical simulator, when compared to no simulator training, is associated with a significantly faster procedure, when performed on a human cadaver. PMID:27752610

Efficiency of endoscopy units can be improved with use of discrete event simulation modeling

PubMed Central

Sauer, Bryan G.; Singh, Kanwar P.; Wagner, Barry L.; Vanden Hoek, Matthew S.; Twilley, Katherine; Cohn, Steven M.; Shami, Vanessa M.; Wang, Andrew Y.

2016-01-01

Background and study aims: The projected increased demand for health services obligates healthcare organizations to operate efficiently. Discrete event simulation (DES) is a modeling method that allows for optimization of systems through virtual testing of different configurations before implementation. The objective of this study was to identify strategies to improve the daily efficiencies of an endoscopy center with the use of DES. Methods: We built a DES model of a five procedure room endoscopy unit at a tertiary-care university medical center. After validating the baseline model, we tested alternate configurations to run the endoscopy suite and evaluated outcomes associated with each change. The main outcome measures included adequate number of preparation and recovery rooms, blocked inflow, delay times, blocked outflows, and patient cycle time. Results: Based on a sensitivity analysis, the adequate number of preparation rooms is eight and recovery rooms is nine for a five procedure room unit (total 3.4 preparation and recovery rooms per procedure room). Simple changes to procedure scheduling and patient arrival times led to a modest improvement in efficiency. Increasing the preparation/recovery rooms based on the sensitivity analysis led to significant improvements in efficiency. Conclusions: By applying tools such as DES, we can model changes in an environment with complex interactions and find ways to improve the medical care we provide. DES is applicable to any endoscopy unit and would be particularly valuable to those who are trying to improve on the efficiency of care and patient experience. PMID:27853739

Issues of public policy in the USA raised by amniocentesis.

PubMed Central

Etzioni, A.

1976-01-01

Amniocentesis, a procedure which can detect during pregnancy whether or not the fetus will develop into a mongol or one affected by other serious chromosomal defects, if given to all pregnant women aged 40 and over, would save both human suffering and economic loss to the community. The procedure is not at present widely used for various reasons, not all of them medical, and, if the test result is positive abortion is the remedy. The author describes an important clinical trial being conducted in the USA at the present time but suggests that an educational programme should be undertaken to inform the public of the existence of this procedure and its applications even before the results of the American large-scale trial can be known and evaluated. Amniocentesis and its use, Professor Etzioni concludes, is not the only genetic tool which should be reviewed in a manner which would give an overall picture. He compares those who are concerned with these matters to the citizens of Britain when they saw the first steam engine. They did not perceive the social changes--the industrial revolution--that would follow. In our time a 'genetic revolution' may not be long delayed. PMID:822165

Percutaneous tracheostomy in patients with cervical spine fractures--feasible and safe.

PubMed

Ben Nun, Alon; Orlovsky, Michael; Best, Lael Anson

2006-08-01

The aim of this study is to evaluate the short and long-term results of percutaneous tracheostomy in patients with documented cervical spine fracture. Between June 2000 and September 2005, 38 consecutive percutaneous tracheostomy procedures were performed on multi-trauma patients with cervical spine fracture. Modified Griggs technique was employed at the bedside in the general intensive care department. Staff thoracic surgeons and anesthesiologists performed all procedures. Demographics, anatomical conditions, presence of co-morbidities and complication rates were recorded. The average operative time was 10 min (6-15). Two patients had minor complications. One patients had minor bleeding (50 cc) and one had mild cellulitis. Nine patients had severe paraparesis or paraplegia prior to the PCT procedure and 29 were without neurological damage. There was no PCT related neurological deterioration. Twenty-eight patients were discharged from the hospital, 21 were decannulated. The average follow-up period was 18 months (1-48). There was no delayed, procedure related, complication. These results demonstrate that percutaneous tracheostomy is feasible and safe in patients with cervical spine fracture with minimal short and long-term morbidity. We believe that percutaneous tracheostomy is the procedure of choice for patients with cervical spine fracture who need prolonged ventilatory support.

On Time Delay Margin Estimation for Adaptive Control and Optimal Control Modification

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2011-01-01

This paper presents methods for estimating time delay margin for adaptive control of input delay systems with almost linear structured uncertainty. The bounded linear stability analysis method seeks to represent an adaptive law by a locally bounded linear approximation within a small time window. The time delay margin of this input delay system represents a local stability measure and is computed analytically by three methods: Pade approximation, Lyapunov-Krasovskii method, and the matrix measure method. These methods are applied to the standard model-reference adaptive control, s-modification adaptive law, and optimal control modification adaptive law. The windowing analysis results in non-unique estimates of the time delay margin since it is dependent on the length of a time window and parameters which vary from one time window to the next. The optimal control modification adaptive law overcomes this limitation in that, as the adaptive gain tends to infinity and if the matched uncertainty is linear, then the closed-loop input delay system tends to a LTI system. A lower bound of the time delay margin of this system can then be estimated uniquely without the need for the windowing analysis. Simulation results demonstrates the feasibility of the bounded linear stability method for time delay margin estimation.

Handover Control Method Using Resource Reservation in Mobile Multimedia Networks

NASA Astrophysics Data System (ADS)

Lee, Dong Chun; Lee, Jong Chan

When handover events occur during the transmission of multimedia traffic, efficient handover control procedures and radio resource allocation are necessary to maintain the same QoS of transmitted multimedia traffic because the QoS may be degraded by additional delay and information loss. In this paper we propose a new handover control method for the next generation mobile multimedia networks, in which the handover setup process is done in advance of a handover request by predicting the handover cell from mobile terminal's current position. The handover procedures for real-time sessions are performed based on the handover cell information and the resource reservation condition. The radio resources in the estimated adjacent cells should be reserved and allocated to guarantee the continuity of the real-time sessions. We conduct a simulation model that is focused on the handover failure rate and packet loss rate. The simulation results show that our proposed method provides better performance than the previous methods.

Age at Exposure to Surgery and Anesthesia in Children and Association With Mental Disorder Diagnosis.

PubMed

Ing, Caleb; Sun, Ming; Olfson, Mark; DiMaggio, Charles J; Sun, Lena S; Wall, Melanie M; Li, Guohua

2017-12-01

Animals exposed to anesthetics during specific age periods of brain development experience neurotoxicity, with neurodevelopmental changes subsequently observed during adulthood. The corresponding vulnerable age in children, however, is unknown. An observational cohort study was performed using a longitudinal dataset constructed by linking individual-level Medicaid claims from Texas and New York from 1999 to 2010. This dataset was evaluated to determine whether the timing of exposure to anesthesia ≤5 years of age for a single common procedure (pyloromyotomy, inguinal hernia, circumcision outside the perinatal period, or tonsillectomy and/or adenoidectomy) is associated with increased subsequent risk of diagnoses for any mental disorder, or specifically developmental delay (DD) such as reading and language disorders, and attention deficit hyperactivity disorder (ADHD). Exposure to anesthesia and surgery was evaluated in 11 separate age at exposure categories: ≤28 days old, >28 days and ≤6 months, >6 months and ≤1 year, and 6-month age intervals between >1 year old and ≤5 years old. For each exposed child, 5 children matched on propensity score calculated using sociodemographic and clinical covariates were selected for comparison. Cox proportional hazards models were used to measure the hazard ratio of a mental disorder diagnosis associated with exposure to surgery and anesthesia. A total of 38,493 children with a single exposure and 192,465 propensity score-matched children unexposed before 5 years of age were included in the analysis. Increased risk of mental disorder diagnosis was observed at all ages at exposure with an overall hazard ratio of 1.26 (95% confidence interval [CI], 1.22-1.30), which did not vary significantly with the timing of exposure. Analysis of DD and ADHD showed similar results, with elevated hazard ratios distributed evenly across all ages, and overall hazard ratios of 1.26 (95% CI, 1.20-1.32) for DD and 1.31 (95% CI, 1.25-1.37) for ADHD. Children who undergo minor surgery requiring anesthesia under age 5 have a small but statistically significant increased risk of mental disorder diagnoses and DD and ADHD diagnoses, but the timing of the surgical procedure does not alter the elevated risks. Based on these findings, there is little support for the concept of delaying a minor procedure to reduce long-term neurodevelopmental risks of anesthesia in children. In evaluating the influence of age at exposure, the types of procedures included may need to be considered, as some procedures are associated with specific comorbid conditions and are only performed at certain ages.

Leveraging delay discounting for health: Can time delays influence food choice?

PubMed

Appelhans, Bradley M; French, Simone A; Olinger, Tamara; Bogucki, Michael; Janssen, Imke; Avery-Mamer, Elizabeth F; Powell, Lisa M

2018-07-01

Delay discounting, the tendency to choose smaller immediate rewards over larger delayed rewards, is theorized to promote consumption of immediately rewarding but unhealthy foods at the expense of long-term weight maintenance and nutritional health. An untested implication of delay discounting models of decision-making is that selectively delaying access to less healthy foods may promote selection of healthier (immediately available) alternatives, even if they may be less desirable. The current study tested this hypothesis by measuring healthy versus regular vending machine snack purchasing before and during the implementation of a 25-s time delay on the delivery of regular snacks. Purchasing was also examined under a $0.25 discount on healthy snacks, a $0.25 tax on regular snacks, and the combination of both pricing interventions with the 25-s time delay. Across 32,019 vending sales from three separate vending locations, the 25-s time delay increased healthy snack purchasing from 40.1% to 42.5%, which was comparable to the impact of a $0.25 discount (43.0%). Combining the delay and the discount had a roughly additive effect (46.0%). However, the strongest effects were seen under the $0.25 tax on regular snacks (53.7%) and the combination of the delay and the tax (50.2%). Intervention effects varied substantially between vending locations. Importantly, time delays did not harm overall vending sales or revenue, which is relevant to the real-world feasibility of this intervention. More investigation is needed to better understand how the impact of time delays on food choice varies across populations, evaluate the effects of time delays on beverage vending choices, and extend this approach to food choices in contexts other than vending machines. ClinicalTrials.gov, NCT02359916. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Human-in-the Loop Evaluation of a Coordinated Arrival Departure Scheduling Operations for Managing Departure Delays at LaGuardia Airport

NASA Technical Reports Server (NTRS)

Lee, Paul U.; Smith, Nancy M.; Bienert, Nancy; Brasil, Connie; Buckley, Nathan; Chevalley, Eric; Homola, Jeffrey; Omar, Faisal; Parke, Bonny; Yoo, Hyo-Sang

2016-01-01

LaGuardia (LGA) departure delay was identified by the stakeholders and subject matter experts as a significant bottleneck in the New York metropolitan area. Departure delay at LGA is primarily due to dependency between LGA's arrival and departure runways: LGA departures cannot begin takeoff until arrivals have cleared the runway intersection. If one-in one-out operations are not maintained and a significant arrival-to-departure imbalance occurs, the departure backup can persist through the rest of the day. At NASA Ames Research Center, a solution called "Departure-sensitive Arrival Spacing" (DSAS) was developed to maximize the departure throughput without creating significant delays in the arrival traffic. The concept leverages a Terminal Sequencing and Spacing (TSS) operations that create and manage the arrival schedule to the runway threshold and added an interface enhancement to the traffic manager's timeline to provide the ability to manually adjust inter-arrival spacing to build precise gaps for multiple departures between arrivals. A more complete solution would include a TSS algorithm enhancement that could automatically build these multi-departure gaps. With this set of capabilities, inter-arrival spacing could be controlled for optimal departure throughput. The concept was prototyped in a human-in-the- loop (HITL) simulation environment so that operational requirements such as coordination procedures, timing and magnitude of TSS schedule adjustments, and display features for Tower, TRACON and Traffic Management Unit could be determined. A HITL simulation was conducted in August 2014 to evaluate the concept in terms of feasibility, controller workload impact, and potential benefits. Three conditions were tested, namely a Baseline condition without scheduling, TSS condition that schedules the arrivals to the runway threshold, and TSS+DSAS condition that adjusts the arrival schedule to maximize the departure throughput. The results showed that during high arrival demand period, departure throughput could be incrementally increased under TSS and TSS+DSAS conditions without compromising the arrival throughput. The concept, operational procedures, and summary results were originally published in ATM20151 but detailed results were omitted. This paper expands on the earlier paper to provide the detailed results on throughput, conformance, safety, flight time/distance, etc. that provide extra insights into the feasibility and the potential benefits on the concept.

Effect of time delay on flying qualities: An update

NASA Technical Reports Server (NTRS)

Smith, R. E.; Sarrafian, S. K.

1986-01-01

Flying qualities problems of modern, full-authority electronic flight control systems are most often related to the introduction of additional time delay in aircraft response to a pilot input. These delays can have a significant effect on the flying qualities of the aircraft. Time delay effects are reexamined in light of recent flight test experience with aircraft incorporating new technology. Data from the X-29A forward-swept-wing demonstrator, a related preliminary in-flight experiment, and other flight observations are presented. These data suggest that the present MIL-F-8785C allowable-control system time delay specifications are inadequate or, at least, incomplete. Allowable time delay appears to be a function of the shape of the aircraft response following the initial delay. The cockpit feel system is discussed as a dynamic element in the flight control system. Data presented indicate that the time delay associated with a significant low-frequency feel system does not result in the predicted degradation in aircraft flying qualities. The impact of the feel system is discussed from two viewpoints: as a filter in the control system which can alter the initial response shape and, therefore, the allowable time delay, and as a unique dynamic element whose delay contribution can potentially be discounted by special pilot loop closures.

Describing-function analysis of a ripple regulator with slew-rate limits and time delays

NASA Technical Reports Server (NTRS)

Wester, Gene W.

1990-01-01

The effects of time delays and slew-rate limits on the steady-state operating points and performance of a free-running ripple regulator are evaluated using describing-function analysis. The describing function of an ideal comparator (no time delays or slew rate limits) has no phase shift and is independent of frequency. It is found that turn-on delay and turn-off delay have different effects on gain and phase and cannot be combined. Comparator hysteresis affects both gain and phase; likewise, time delays generally affect both gain and phase. It is found that the effective time delay around the feedback loop is one half the sum of turn-on and turn-off delays, regardless of whether the delays are caused by storage time or slew rate limits. Expressions are formulated for the switching frequency, switch duty ratio, dc output, and output ripple. For the case of no hysteresis, a simple, graphical solution for the switching frequency is possible, and the resulting switching frequency is independent of first-order variations of input or load.

Thresholds of Auditory-Motor Coupling Measured with a Simple Task in Musicians and Non-Musicians: Was the Sound Simultaneous to the Key Press?

PubMed Central

van Vugt, Floris T.; Tillmann, Barbara

2014-01-01

The human brain is able to predict the sensory effects of its actions. But how precise are these predictions? The present research proposes a tool to measure thresholds between a simple action (keystroke) and a resulting sound. On each trial, participants were required to press a key. Upon each keystroke, a woodblock sound was presented. In some trials, the sound came immediately with the downward keystroke; at other times, it was delayed by a varying amount of time. Participants were asked to verbally report whether the sound came immediately or was delayed. Participants' delay detection thresholds (in msec) were measured with a staircase-like procedure. We hypothesised that musicians would have a lower threshold than non-musicians. Comparing pianists and brass players, we furthermore hypothesised that, as a result of a sharper attack of the timbre of their instrument, pianists might have lower thresholds than brass players. Our results show that non-musicians exhibited higher thresholds for delay detection (180±104 ms) than the two groups of musicians (102±65 ms), but there were no differences between pianists and brass players. The variance in delay detection thresholds could be explained by variance in sensorimotor synchronisation capacities as well as variance in a purely auditory temporal irregularity detection measure. This suggests that the brain's capacity to generate temporal predictions of sensory consequences can be decomposed into general temporal prediction capacities together with auditory-motor coupling. These findings indicate that the brain has a relatively large window of integration within which an action and its resulting effect are judged as simultaneous. Furthermore, musical expertise may narrow this window down, potentially due to a more refined temporal prediction. This novel paradigm provides a simple test to estimate the temporal precision of auditory-motor action-effect coupling, and the paradigm can readily be incorporated in studies investigating both healthy and patient populations. PMID:24498299

Delay of Treatment Initiation Does Not Adversely Affect Survival Outcome in Breast Cancer.

PubMed

Yoo, Tae-Kyung; Han, Wonshik; Moon, Hyeong-Gon; Kim, Jisun; Lee, Jun Woo; Kim, Min Kyoon; Lee, Eunshin; Kim, Jongjin; Noh, Dong-Young

2016-07-01

Previous studies examining the relationship between time to treatment and survival outcome in breast cancer have shown inconsistent results. The aim of this study was to analyze the overall impact of delay of treatment initiation on patient survival and to determine whether certain subgroups require more prompt initiation of treatment. This study is a retrospective analysis of stage I-III patients who were treated in a single tertiary institution between 2005 and 2008. Kaplan-Meier survival analysis and Cox proportional hazards regression model were used to evaluate the impact of interval between diagnosis and treatment initiation in breast cancer and various subgroups. A total of 1,702 patients were included. Factors associated with longer delay of treatment initiation were diagnosis at another hospital, medical comorbidities, and procedures performed before admission for surgery. An interval between diagnosis and treatment initiation as a continuous variable or with a cutoff value of 15, 30, 45, and 60 days had no impact on disease-free survival (DFS). Subgroup analyses for hormone-responsiveness, triple-negative breast cancer, young age, clinical stage, and type of initial treatment showed no significant association between longer delay of treatment initiation and DFS. Our results show that an interval between diagnosis and treatment initiation of 60 days or shorter does not appear to adversely affect DFS in breast cancer.

A Cooperative Traffic Control of Vehicle–Intersection (CTCVI) for the Reduction of Traffic Delays and Fuel Consumption

PubMed Central

Li, Jinjian; Dridi, Mahjoub; El-Moudni, Abdellah

2016-01-01

The problem of reducing traffic delays and decreasing fuel consumption simultaneously in a network of intersections without traffic lights is solved by a cooperative traffic control algorithm, where the cooperation is executed based on the connection of Vehicle-to-Infrastructure (V2I). This resolution of the problem contains two main steps. The first step concerns the itinerary of which intersections are chosen by vehicles to arrive at their destination from their starting point. Based on the principle of minimal travel distance, each vehicle chooses its itinerary dynamically based on the traffic loads in the adjacent intersections. The second step is related to the following proposed cooperative procedures to allow vehicles to pass through each intersection rapidly and economically: on one hand, according to the real-time information sent by vehicles via V2I in the edge of the communication zone, each intersection applies Dynamic Programming (DP) to cooperatively optimize the vehicle passing sequence with minimal traffic delays so that the vehicles may rapidly pass the intersection under the relevant safety constraints; on the other hand, after receiving this sequence, each vehicle finds the optimal speed profiles with the minimal fuel consumption by an exhaustive search. The simulation results reveal that the proposed algorithm can significantly reduce both travel delays and fuel consumption compared with other papers under different traffic volumes. PMID:27999333

An Inequality Constrained Least-Squares Approach as an Alternative Estimation Procedure for Atmospheric Parameters from VLBI Observations

NASA Astrophysics Data System (ADS)

Halsig, Sebastian; Artz, Thomas; Iddink, Andreas; Nothnagel, Axel

2016-12-01

On its way through the atmosphere, radio signals are delayed and affected by bending and attenuation effects relative to a theoretical path in vacuum. In particular, the neutral part of the atmosphere contributes considerably to the error budget of space-geodetic observations. At the same time, space-geodetic techniques become more and more important in the understanding of the Earth's atmosphere, because atmospheric parameters can be linked to the water vapor content in the atmosphere. The tropospheric delay is usually taken into account by applying an adequate model for the hydrostatic component and by additionally estimating zenith wet delays for the highly variable wet component. Sometimes, the Ordinary Least Squares (OLS) approach leads to negative estimates, which would be equivalent to negative water vapor in the atmosphere and does, of course, not reflect meteorological and physical conditions in a plausible way. To cope with this phenomenon, we introduce an Inequality Constrained Least Squares (ICLS) method from the field of convex optimization and use inequality constraints to force the tropospheric parameters to be non-negative allowing for a more realistic tropospheric parameter estimation in a meteorological sense. Because deficiencies in the a priori hydrostatic modeling are almost fully compensated by the tropospheric estimates, the ICLS approach urgently requires suitable a priori hydrostatic delays. In this paper, we briefly describe the ICLS method and validate its impact with regard to station positions.

Market-based control strategy for long-span structures considering the multi-time delay issue

NASA Astrophysics Data System (ADS)

Li, Hongnan; Song, Jianzhu; Li, Gang

2017-01-01

To solve the different time delays that exist in the control device installed on spatial structures, in this study, discrete analysis using a 2 N precise algorithm was selected to solve the multi-time-delay issue for long-span structures based on the market-based control (MBC) method. The concept of interval mixed energy was introduced from computational structural mechanics and optimal control research areas, and it translates the design of the MBC multi-time-delay controller into a solution for the segment matrix. This approach transforms the serial algorithm in time to parallel computing in space, greatly improving the solving efficiency and numerical stability. The designed controller is able to consider the issue of time delay with a linear controlling force combination and is especially effective for large time-delay conditions. A numerical example of a long-span structure was selected to demonstrate the effectiveness of the presented controller, and the time delay was found to have a significant impact on the results.

Delay time and Hartman effect in strain engineered graphene

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

Chen, Xi, E-mail: xchen@shu.edu.cn; Deng, Zhi-Yong; Ban, Yue, E-mail: yban@shu.edu.cn

2014-05-07

Tunneling times, including group delay and dwell time, are studied for massless Dirac electrons transmitting through a one-dimensional barrier in strain-engineered graphene. The Hartman effect, the independence of group delay on barrier length, is induced by the strain effect, and associated with the transmission gap and the evanescent mode. The influence of barrier height/length and strain modulus/direction on the group delay is also discussed, which provides the flexibility to control the group delay with applications in graphene-based devices. The relationship between group delay and dwell time is finally derived to clarify the nature of the Hartman effect.

Reconstructions of parameters of radiophysical chaotic generator with delayed feedback from short time series

NASA Astrophysics Data System (ADS)

Ishbulatov, Yu. M.; Karavaev, A. S.; Kiselev, A. R.; Semyachkina-Glushkovskaya, O. V.; Postnov, D. E.; Bezruchko, B. P.

2018-04-01

A method for the reconstruction of time-delayed feedback system is investigated, which is based on the detection of synchronous response of a slave time-delay system with respect to the driving from the master system under study. The structure of the driven system is similar to the structure of the studied time-delay system, but the feedback circuit is broken in the driven system. The method efficiency is tested using short and noisy data gained from an electronic chaotic oscillator with time-delayed feedback.

Stationary phase method and delay times for relativistic and non-relativistic tunneling particles

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

Bernardini, A.E.

2009-06-15

The stationary phase method is frequently adopted for calculating tunneling phase times of analytically-continuous Gaussian or infinite-bandwidth step pulses which collide with a potential barrier. This report deals with the basic concepts on deducing transit times for quantum scattering: the stationary phase method and its relation with delay times for relativistic and non-relativistic tunneling particles. After reexamining the above-barrier diffusion problem, we notice that the applicability of this method is constrained by several subtleties in deriving the phase time that describes the localization of scattered wave packets. Using a recently developed procedure - multiple wave packet decomposition - for somemore » specifical colliding configurations, we demonstrate that the analytical difficulties arising when the stationary phase method is applied for obtaining phase (traversal) times are all overcome. In this case, we also investigate the general relation between phase times and dwell times for quantum tunneling/scattering. Considering a symmetrical collision of two identical wave packets with an one-dimensional barrier, we demonstrate that these two distinct transit time definitions are explicitly connected. The traversal times are obtained for a symmetrized (two identical bosons) and an antisymmetrized (two identical fermions) quantum colliding configuration. Multiple wave packet decomposition shows us that the phase time (group delay) describes the exact position of the scattered particles and, in addition to the exact relation with the dwell time, leads to correct conceptual understanding of both transit time definitions. At last, we extend the non-relativistic formalism to the solutions for the tunneling zone of a one-dimensional electrostatic potential in the relativistic (Dirac to Klein-Gordon) wave equation where the incoming wave packet exhibits the possibility of being almost totally transmitted through the potential barrier. The conditions for the occurrence of accelerated and, eventually, superluminal tunneling transmission probabilities are all quantified and the problematic superluminal interpretation based on the non-relativistic tunneling dynamics is revisited. Lessons concerning the dynamics of relativistic tunneling and the mathematical structure of its solutions suggest revealing insights into mathematically analogous condensed-matter experiments using electrostatic barriers in single- and bi-layer graphene, for which the accelerated tunneling effect deserves a more careful investigation.« less

Comparison of operative notes with real-time observation of adhesiolysis-related complications during surgery.

PubMed

ten Broek, R P G; van den Beukel, B A W; van Goor, H

2013-02-01

The operative report contains critical information for patient care, serves an educational purpose and is an important source for surgical research. Recent studies demonstrate that operative reports are unstructured and lack vital components. The accuracy of the operative notes has never been assessed. The aim of this study was to analyse the accuracy of operative reports by comparing notes with intraoperative observer-derived findings regarding adhesions and adhesiolysis-related complications. The incidence of adhesions and adhesiolysis-induced injury were scored from the reports by a researcher blinded to operative findings obtained prospectively by direct observation. In addition, factors influencing correct reporting were analysed, including sex, surgical experience, delay in dictation, and the gradual introduction of a new report template with a focus on describing operative findings rather than actions taken. A total of 755 consecutive operative reports were analysed. Sensitivity and specificity for the incidence of adhesions was 85·1 and 72·4 per cent respectively. Six of 43 inadvertent enterotomies, and 17 of 48 other organ injuries, had not been reported. All missed bowel injuries were found in reports written in the old template. A median delay in dictating of 3 (range 1-226) working days was found for 56 reports (7·4 per cent). Documentation of inadvertent enterotomies was missing more often in delayed reports (2 of 3 versus 4 of 40 reports dictated with no delay; P = 0·022). The sensitivity and specificity of operative reports noting adhesions and adhesiolysis were low. One in seven enterotomies was not reported. Effort should be put into teaching timely, meaningful, structured and accurate reporting of surgical procedures. Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

A Simulation Based Investigation of High Latency Space Systems Operations

NASA Technical Reports Server (NTRS)

Li, Zu Qun; Moore, Michael; Bielski, Paul; Crues, Edwin Z.

2017-01-01

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions and assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

A Simulation Based Investigation of High Latency Space Systems Operations

NASA Technical Reports Server (NTRS)

Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; Moore, Michael

2017-01-01

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control system, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions, and to assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

Risk profile and treatment options of acute ischemic in-hospital stroke.

PubMed

Schürmann, Kolja; Nikoubashman, Omid; Falkenburger, Björn; Tauber, Simone C; Wiesmann, Martin; Schulz, Jörg B; Reich, Arno

2016-03-01

Despite the potential immediate access to diagnosis and care, in-hospital stroke (IHS) is associated with delay in diagnosis, lower rates of reperfusion treatment, and unfavorable outcome. Endovascular reperfusion therapy has shown promising results in recent trials for community-onset strokes (COS) and is limited by less contraindications than systemic thrombolysis. Thus, endovascular approaches may offer additional acute treatment options for IHS. We performed a retrospective, observational monocentric analysis of patients with acute ischemic stroke between January 2010 and December 2014. Out of 3506 acute ischemic strokes, 331 (9.4%) were IHS. In-hospital mortality (31.4 vs. 8.0%) and duration of stay after stroke (19.5 vs. 12.1 days) were higher in IHS than in COS. Most IHS occurred in cardiologic and cardiosurgical patients after catheterization or surgery. In 111 cases (33.5%) the time of onset could not be established as a result of sedation or delayed referral resulting in delayed symptom recognition. 52 IHS (15.7%) and 828 COS (26.0%, p < 0.001) patients received any kind of reperfusion therapy, of which 59.6% (IHS) and 12.1% (COS) comprised isolated endovascular interventions (p < 0.001). Intra-hospital delays (time to brain imaging, systemic thrombolysis, and angiography) were longer and outcome parameters (mRS d90, in-hospital mortality, length of stay) were worse in IHS, whereas rates of procedural complications and intracranial hemorrhages were similar in both groups. The overall rate of reperfusion treatment is lower in IHS compared to COS, as IHS patients are less likely to be eligible for systemic thrombolysis. Interventional stroke treatment is a safe and feasible therapeutic option for patients who are not eligible for systemic thrombolysis and should be anticipated whenever IHS is diagnosed.

Percutaneous drainage of Morel-Lavallée lesions when the diagnosis is delayed.

PubMed

Zhong, Biao; Zhang, Chi; Luo, Cong-feng

2014-10-01

Morel-Lavallée lesions are a closed internal degloving, and open débridement can damage the only remaining blood supply to the skin. We performed percutaneous draining and débridement to treat 8 patients in whom the diagnosis of Morel-Lavallée lesions was delayed more than 1 week. Here we discuss our treatment procedures and the outcomes in these 8 patients. We consider percutaneous drainage to be an effective treatment for patients with delayed diagnosis of Morel-Lavallée lesions.

Delay of smoking gratification as a laboratory model of relapse: effects of incentives for not smoking, and relationship with measures of executive function.

PubMed

Mueller, Eldon T; Landes, Reid D; Kowal, Benjamin P; Yi, Richard; Stitzer, Maxine L; Burnett, Cody A; Bickel, Warren K

2009-09-01

Nineteen nicotine-deprived cigarette smokers received monetary rewards for each minute they chose not to initiate smoking in 2-h laboratory sessions followed by a 30-min period of enforced abstinence from smoking. Reinforcer amounts were delivered according to one of three schedules: increasing, decreasing, and constant. Relapse time (time until first cigarette) was shortest in the decreasing condition, longest in the increasing condition, and intermediate in the constant condition. All differences were significant except in the constant-decreasing comparison. The relationships between a battery of baseline assessments and relapse times were examined. Relapse times were predicted by delay-discounting coefficients (k) for $10 and $1000 in money and for $1000 of cigarettes. Relapse times were also predicted by the number of cigarettes smoked daily and a Wisconsin Card Sorting Test score. Performance on the Stroop Task and the Fagerström Test for Nicotine Dependence differentiated participants dichotomized into those who relapsed 'earlier' in sessions versus those who first smoked 'later'. The variability in some scores from smoking-urges and affect questionnaires administered after smoking-room sessions was explained by measures related to in-session nicotine intake. Results are discussed as they relate to contingency-management procedures, predictors of relapse, and the competing neurobehavioral decision systems theory of addiction.

Delay of Smoking Gratification as a Laboratory Model of Relapse: Effects of Incentives for Not Smoking, and Relationship to Measures of Executive Function

PubMed Central

Mueller, E. Terry; Landes, Reid D.; Kowal, Benjamin P.; Yi, Richard; Stitzer, Maxine L.; Burnett, Cody A.; Bickel, Warren K.

2010-01-01

Nineteen nicotine-deprived cigarette smokers received monetary rewards for each minute they choose not to initiate smoking in 2-hour laboratory sessions followed by a 30-min period of enforced abstinence from smoking. Reinforcer amounts were delivered according to one of three schedules: increasing, decreasing, and constant. Relapse time (time until first smoke) was shortest in the decreasing condition, longest in the increasing condition, and intermediate in the constant condition. All differences were significant except in the constant-decreasing comparison. The relationships between a battery of baseline assessments and relapse times were examined. Relapse times were predicted by delay-discounting coefficients (k) for $10 and $1000 in money, and for $1000 of cigarettes. Relapse times were also predicted by the number of cigarettes smoked daily and a Wisconsin Card Sorting Test score. Performance on the Stroop Task and the Fagerström Test for Nicotine Dependence differentiated participants dichotomized into those who relapsed “earlier” in sessions versus those who first smoked “later.” Variability on some scores from smoking-urges and affect questionnaires administered after smoking-room sessions was explained by measures related to in-session nicotine intake. Results are discussed as they relate to contingency-management procedures, predictors of relapse, and the competing neuro-behavioral decision systems theory of addiction. PMID:19741301

Reconstruction of ensembles of coupled time-delay systems from time series.

PubMed

Sysoev, I V; Prokhorov, M D; Ponomarenko, V I; Bezruchko, B P

2014-06-01

We propose a method to recover from time series the parameters of coupled time-delay systems and the architecture of couplings between them. The method is based on a reconstruction of model delay-differential equations and estimation of statistical significance of couplings. It can be applied to networks composed of nonidentical nodes with an arbitrary number of unidirectional and bidirectional couplings. We test our method on chaotic and periodic time series produced by model equations of ensembles of diffusively coupled time-delay systems in the presence of noise, and apply it to experimental time series obtained from electronic oscillators with delayed feedback coupled by resistors.

Laparoscopic inguinal hernia repair.

PubMed

Hussein, M K; Khoury, G S; Taha, A M

1998-01-01

Open hernia repair is associated with significant postoperative pain and disability resulting in delayed return to full activity. Laparoscopic hernia repair has been advocated as the procedure that combines the benefit of tension-free repair with the preservation of the basic anatomy of the inguinal area. We present our experience with 803 laparoscopic hernia repairs in 517 patients over a period of 66 months (August 92 to February 98). The effects of the learning curve and the refinement of the technique had their impact on earlier results and complications. However, with more experience we found that the laparoscopic preperitoneal approach is safe and efficacious. There was no mortality. Most patients (85%) were discharged home within 24 h of the procedure and returned to full activity within 10 days. Patient satisfaction was excellent. The complication rate decreased and operative time was reduced with experience. This procedure is clearly indicated in patients who have recurrent or bilateral hernias. It is associated with shorter convalescence and a quick return to work.

Stability of Nonlinear Systems with Unknown Time-varying Feedback Delay

NASA Astrophysics Data System (ADS)

Chunodkar, Apurva A.; Akella, Maruthi R.

2013-12-01

This paper considers the problem of stabilizing a class of nonlinear systems with unknown bounded delayed feedback wherein the time-varying delay is 1) piecewise constant 2) continuous with a bounded rate. We also consider application of these results to the stabilization of rigid-body attitude dynamics. In the first case, the time-delay in feedback is modeled specifically as a switch among an arbitrarily large set of unknown constant values with a known strict upper bound. The feedback is a linear function of the delayed states. In the case of linear systems with switched delay feedback, a new sufficiency condition for average dwell time result is presented using a complete type Lyapunov-Krasovskii (L-K) functional approach. Further, the corresponding switched system with nonlinear perturbations is proven to be exponentially stable inside a well characterized region of attraction for an appropriately chosen average dwell time. In the second case, the concept of the complete type L-K functional is extended to a class of nonlinear time-delay systems with unknown time-varying time-delay. This extension ensures stability robustness to time-delay in the control design for all values of time-delay less than the known upper bound. Model-transformation is used in order to partition the nonlinear system into a nominal linear part that is exponentially stable with a bounded perturbation. We obtain sufficient conditions which ensure exponential stability inside a region of attraction estimate. A constructive method to evaluate the sufficient conditions is presented together with comparison with the corresponding constant and piecewise constant delay. Numerical simulations are performed to illustrate the theoretical results of this paper.

Effect of metrology time delay on overlay APC

NASA Astrophysics Data System (ADS)

Carlson, Alan; DiBiase, Debra

2002-07-01

The run-to-run control strategy of lithography APC is primarily composed of a feedback loop as shown in the diagram below. It is known that the insertion of a time delay in a feedback loop can cause degradation in control performance and could even cause a stable system to become unstable, if the time delay becomes sufficiently large. Many proponents of integrated metrology methods have cited the damage caused by metrology time delays as the primary justification for moving from a stand-alone to integrated metrology. While there is little dispute over the qualitative form of this argument, there has been very light published about the quantitative effects under real fab conditions - precisely how much control is lost due to these time delays. Another issue regarding time delays is that the length of these delays is not typically fixed - they vary from lot to lot and in some cases this variance can be large - from one hour on the short side to over 32 hours on the long side. Concern has been expressed that the variability in metrology time delays can cause undesirable dynamics in feedback loops that make it difficult to optimize feedback filters and gains and at worst could drive a system unstable. By using data from numerous fabs, spanning many sizes and styles of operation, we have conducted a quantitative study of the time delay effect on overlay run- to-run control. Our analysis resulted in the following conclusions: (1) There is a significant and material relationship between metrology time delay and overlay control under a variety of real world production conditions. (2) The run-to-run controller can be configured to minimize sensitivity to time delay variations. (3) The value of moving to integrated metrology can be quantified.

Reduction of Weather-Related Terminal Area Delays in the Free-Flight Era

NASA Technical Reports Server (NTRS)

Johnson, Sally C.; Chin, David K.; Rovinsky, Robert B.; Kostiuk, Peter F.; Lee, David A.; Hemm, Robert V.; Wingrove, Earl R., III

1996-01-01

While much of the emphasis of the free-flight movement has been concentrated on reducing en-route delays, airport capacity is a major bottleneck in the current airspace system, particularly during bad weather. According to the Air Transport Association (ATA) Air Carrier Delay Reports, ground delays (gate-hold, taxi-in, and taxi-out) comprise 75 percent of total delays. It is likely that the projected steady growth in traffic will only exacerbate these losses. Preliminary analyses show that implementation of the terminal area technologies and procedures under development in NASA s Terminal Area Productivity program can potentially save the airlines at least $350M annually in weather-related delays by the year 2005 at Boston Logan and Detroit airports alone. This paper briefly describes the Terminal Area Productivity program, outlines the costhenefit analyses that are being conducted in support of the program, and presents some preliminary analysis results.

Digital time delay

DOEpatents

Martin, A.D.

1986-05-09

Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay provides a first output signal at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits latch the high resolution data to form a first synchronizing data set. A selected time interval has been preset to internal counters and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses count down the counters to generate an internal pulse delayed by an internal which is functionally related to the preset time interval. A second LCD corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD to generate a second set of synchronizing data which is complementary with the first set of synchronizing data for presentation to logic circuits. The logic circuits further delay the internal output signal with the internal pulses. The final delayed output signal thereafter enables the output pulse generator to produce the desired output pulse at the preset time delay interval following input of the trigger pulse.

Delay-Induced Attenuation of Latent Inhibition with a Conditioned Emotional Response Depends on CS-US Strength

ERIC Educational Resources Information Center

De la Casa, Luis G.; Diaz, Estrella; Lubow, R.E.

2005-01-01

Latent Inhibition (LI) attenuation when a long delay is introduced between acquisition and test phases has been repeatedly observed using aversive conditioning procedures (e.g., Aguado, Symonds, & Hall, 1994). This effect has been used as evidence to support those theories that consider LI to be the result of a retrieval failure. We designed three…

Rapid Acquisition of Preference in Concurrent Chains: Effects of "d"-Amphetamine on Sensitivity to Reinforcement Delay

ERIC Educational Resources Information Center

Ta, Wei-Min; Pitts, Raymond C.; Hughes, Christine E.; McLean, Anthony P.; Grace, Randolph C.

2008-01-01

The purpose of this study was to examine effects of "d"-amphetamine on choice controlled by reinforcement delay. Eight pigeons responded under a concurrent-chains procedure in which one terminal-link schedule was always fixed- interval 8 s, and the other terminal-link schedule changed from session to session between fixed-interval 4 s and…

Manipulation of Motivating Operations and Use of a Script-Fading Procedure to Teach Mands for Location to Children with Language Delays

ERIC Educational Resources Information Center

Howlett, Melissa A.; Sidener, Tina M.; Progar, Patrick R.; Sidener, David W.

2011-01-01

The effects of contriving motivating operations (MOs) and script fading on the acquisition of the mand "Where's [object]?" were evaluated in 2 boys with language delays. During each session, trials were alternated in which high-preference items were present (abolishing operation [AO] trials) or missing (establishing operation [EO] trials) from…

Delayed Feedback Disrupts the Procedural-Learning System but Not the Hypothesis-Testing System in Perceptual Category Learning

ERIC Educational Resources Information Center

Maddox, W. Todd; Ing, A. David

2005-01-01

W. T. Maddox, F. G. Ashby, and C. J. Bohil (2003) found that delayed feedback adversely affects information-integration but not rule-based category learning in support of a multiple-systems approach to category learning. However, differences in the number of stimulus dimensions relevant to solving the task and perceptual similarity failed to rule…

Intra-articular Implantation of Mesenchymal Stem Cells, Part 1

PubMed Central

Kraeutler, Matthew J.; Mitchell, Justin J.; Chahla, Jorge; McCarty, Eric C.; Pascual-Garrido, Cecilia

2017-01-01

Osteoarthritis (OA) after a partial or total meniscectomy procedure is a common pathology. Because of the high incidence of meniscectomy in the general population, as well as the significant burden of knee OA, there is increasing interest in determining methods for delaying postmeniscectomy OA. Biological therapies, including mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), have been proposed as possible therapies that could delay OA in this and other settings. Several studies in various animal models have evaluated the effect of injecting MSCs into the knee joints of animals with OA induced either by meniscal excision with or without anterior cruciate ligament transection. When compared with control groups receiving injections without progenitor cells, short-term benefits in the experimental groups have been reported. In human subjects, there are limited data to determine the effect of biological therapies for use in delaying or preventing the onset of OA after a meniscectomy procedure. The purpose of this review is to highlight the findings in the presently available literature on the use of intra-articular implantation of MSCs postmeniscectomy and to offer suggestions for future research with the goal of delaying or treating early OA postmeniscectomy with MSCs. PMID:28203597

Traversal of electromagnetic pulses through dispersive media with negative refractive index

NASA Astrophysics Data System (ADS)

Nanda, L.; Ramakrishna, S. A.

2017-05-01

We investigate the traversal of electromagnetic pulses through dispersive media with negative refractive index in such a way that no resonant effects come into play. It has been verified that for evanescent waves, the definitions of the group delay and the reshaping delay times get interchanged in comparison to the propagating waves. We show that for a negative refractive index medium (NRM) with ɛ(ω)=μ(ω), the reshaping delay time identically vanishes for propagating waves. The total delay time in NRM is otherwise contributed by both the group and the reshaping delay times, whereas for the case of broadband pulses in NRM the total delay time is always subluminal.

Simulation analysis of the effect of initial delay on flight delay diffusion

NASA Astrophysics Data System (ADS)

Que, Zufu; Yao, Hongguang; Yue, Wei

2018-01-01

The initial delay of the flight is an important factor affecting the spread of flight delays, so clarifying their relationship conduces to control flight delays in the aeronautical network. Through establishing a model of the chain aviation network and making simulation analysis of the effects of initial delay on the delay longitudinal diffusion, it’s found that the number of delayed airports in the air network, the total delay time and the average delay time of the delayed airport are generally positively correlated with the initial delay. This indicates that the occurrence of the initial delay should be avoided or reduced as much as possible to improve the punctuality of the flight.

Efficacy and adverse events of cold vs hot polypectomy: A meta-analysis.

PubMed

Fujiya, Mikihiro; Sato, Hiroki; Ueno, Nobuhiro; Sakatani, Aki; Tanaka, Kazuyuki; Dokoshi, Tatsuya; Fujibayashi, Shugo; Nomura, Yoshiki; Kashima, Shin; Gotoh, Takuma; Sasajima, Junpei; Moriichi, Kentaro; Watari, Jiro; Kohgo, Yutaka

2016-06-21

To compare previously reported randomized controlled studies (RCTs) of cold and hot polypectomy, we systematically reviewed and clarify the utility of cold polypectomy over hot with respect to efficacy and adverse events. A meta-analysis was conducted to evaluate the predominance of cold and hot polypectomy for removing colon polyps. Published articles and abstracts from worldwide conferences were searched using the keywords "cold polypectomy". RCTs that compared either or both the effects or adverse events of cold polypectomy with those of hot polypectomy were collected. The patients' demographics, endoscopic procedures, No. of examined lesions, lesion size, macroscopic and histologic findings, rates of incomplete resection, bleeding amount, perforation, and length of procedure were extracted from each study. A forest plot analysis was used to verify the relative strength of the effects and adverse events of each procedure. A funnel plot was generated to assess the possibility of publication bias. Ultimately, six RCTs were selected. No significant differences were noted in the average lesion size (less than 10 mm) between the cold and hot polypectomy groups in each study. Further, the rates of complete resection and adverse events, including delayed bleeding, did not differ markedly between cold and hot polypectomy. The average procedural time in the cold polypectomy group was significantly shorter than in the hot polypectomy group. Cold polypectomy is a time-saving procedure for removing small polyps with markedly similar curability and safety to hot polypectomy.

12 CFR 509.22 - Consolidation and severance of actions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... PRACTICE AND PROCEDURE IN ADJUDICATORY PROCEEDINGS Uniform Rules of Practice and Procedure § 509.22... administrative law judge's own motion, the administrative law judge may consolidate, for some or all purposes... common question of law or fact, unless such consolidation would cause unreasonable delay or injustice. (2...

34 CFR 303.300 - State eligibility criteria and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... INFANTS AND TODDLERS WITH DISABILITIES Program and Service Components of a Statewide System of Early... procedures, including the use of informed clinical opinion, that will be used to measure a child's development; and (2) Stating the levels of functioning or other criteria that constitute a developmental delay...