Interval Schedule Research Articles

Komparasi Efektivitas Tiga Tipe Starter Generator yang Digunakan Pada Engine Pesawat ATR

A starter generator (DC generator) is a DC machine that acts as a motor when starting the engine and will become a DC generator when it reaches a certain speed. The DC Starter Generator will function as a starter mode when the speed is <45% NH and will become a DC generator mode when the speed is >61.5%. There are several types of starter generators on ATR aircraft: 8260-121, 8260-123, and 8260-124. The uses and functions of the three types are the same, but the maintenance schedule intervals are different. Therefore, the purpose of this study was to determine the planned maintenance intervals (brush change, bearing change, and overhaul) and the causes of differences in maintenance intervals for the starter generator. The type of research used is comparative research, where this research compares several parameters related to the planned maintenance of the Starter Generator, which will be operated within 10,000 FH. The results of the treatment intervals obtained are that types 8260-121 and 8260-123 each will require 16 times maintenance, while types 8260-124 only need 8 times maintenance. The difference in the number of treatments being less in the 8260-124 type is due to the modification of the brush. In addition, the type 8260-124 has also used a new technology commutator. Therefore, this type is superior to the other two because it can save operational aircraft costs.

Rethinking Time-to-Exchange: Outcomes of Nephrostomy Tube Placement in Pregnancy

This study evaluated outcomes for percutaneous nephrostomy tube placement in pregnant patients, including potential complications that required early, unplanned tube exchange. A retrospective review was conducted for 51 pregnant patients and a nonpregnant cohort matched 1:1 who received percutaneous nephrostomy tube placement between 2012 and 2020. Factors potentially contributing to unplanned tube exchanges were analyzed, including gestational age, prevalence and severity of hydronephrosis, presence of renal calculi, and serum calcium level. The mean tube exchange interval was significantly shorter in the pregnant group (3.4 weeks ± 1.8 [standard deviation] vs 5.7 weeks ± 0.7, P < .0001), and pregnant subjects were significantly more likely to require reintervention before the 6-week scheduled exchange (80.4% vs 21.6%, P < .0001). The serum calcium level was lower in pregnant subjects (8.4 mg/dL ± 0.4 vs 8.9 mg/dL ± 0.7, P = .002). A shorter interval schedule (every 3 weeks) of routine percutaneous nephrostomy tube exchange in pregnant patients may be necessary to avoid complications.

Relationship between reinforcement rate and response rate in Pavlovian and operant conditioning with compound stimuli in rats

Harris, Andrew, and Livesey (2012) proposed that response rate (R) to a stimulus (e.g., A) of a compound (e.g., AB) would be directly related to the difference between reinforcement rate (r) during AB and the other stimulus (e.g., B). To explore the extent of this proposal to operant conditioning, three experiments were carried out. Experiment 1 replicated Harris et al. (2012 – Experiment 1) using sucrose as US in Pavlovian conditioning. In Experiment 2 rats pressed a lever under a variable interval schedule in two phases. In Training, responses during a compound stimulus AB100% were reinforced 100%, responses during B50% and C50% 50% and responses during D25%, 25% of the trials. Then, nonreinforced A trials were introduced (Probe). Results from Experiment 2 showed that r controlled the R to AB100%, B50%, C50% and D25% during training and probe, however, were inconclusive about r and R relationship during A. In Experiment 3, responses during A100% were reinforced 100% and during B50% and C50% 50% of the trials (Training). Next, nonreinforced BC trials were presented (Probe). Results from Experiment 3 showed that response rate during BC were similar to A100%, but higher than B50% and C50%, suggesting summation of B50% and C50% reinforcement rates. Overall, the results showed that Harris et al. (2012) proposal extends to discriminative operant relations.

Identification of New Biomarker for Prediction of Hepatocellular Carcinoma Development in Early-Stage Cirrhosis Patients.

Background Liver cirrhosis is one of the major drivers of hepatocellular carcinoma (HCC). In the present study, we aimed to identify and validate new biomarker for early prediction of HCC development in early-stage cirrhosis patients. Methods mRNA expression and clinical parameters of GSE63898, GSE89377, GSE15654, GSE14520, and TCGA-HCC cohort and ICGC-HCC cohort were downloaded for analysis. Wilcoxon test was performed to identify DEGs. Univariate and multivariate Cox regression analysis were used to develop the risk signature, and ROC analysis was performed to analyze the predictive accuracy and sensitivity of the risk signature. Results There were 42 DEGs (including 28 upregulated genes and 14 downregulated genes) found in early-stage liver cirrhosis patients before developing HCC from GSE1565442. Then, a risk signature consisting of 8 DEGs could effectively classify early-stage cirrhosis patients into high-risk group with shorter HCC development time and low-risk group with longer HCC development time from GSE15654. Multivariate Cox analysis indicated that the risk signature was an independent prognostic factor for the prediction of HCC development and ROC analysis showed that the signature exhibited good predictive efficiency in predicting 2-, 5-, and 10-year HCC development. Mechanistically, significantly higher proportions of CD8 T cells were found to be enriched in cirrhosis patients with low risk score, and higher CD8 T cells were associated with longer HCC development time. Besides, the signature was an independent prognostic factor for poorer prognosis of early-stage liver cirrhosis patients of GSE15654. Moreover, the signature could also separate HCC patients from healthy controls and was also associated with the poorer prognosis of HCC patients from three HCC cohorts. Finally, we also identified HDAC inhibitors, such as trichostatin A, to be a potential chemopreventive treatment for the prevention of HCC development by targeting risk signature based on CMap analysis. Conclusion A risk signature was developed and validated for early prediction of HCC development, which may be a useful tool to set up individualized follow-up interval schedules.

Effect of depression and anxiety on human schedule performance

Two experiments examined the impact of depression and anxiety on the microstructure of human schedule responding. Human participants responded by pressing a computer key for points on a multiple random ratio (RR) random interval (RI) schedule. The RI schedule was yoked to the RR schedule in terms of reinforcement rate within subject. Overall response rates were higher on the RR compared to the RI schedule. In both experiments, the presence of psychometrically-measured depressive traits reduced overall levels of responding. Depressive traits also decreased within-bout responding, but increased levels of bout-initiation responding. These findings regarding the microstructure of responding were not noted for anxiety traits. These results suggest that depression impacts learning by working through a number of different mechanisms – both impacting the perceived value of the reinforcer, and possibly by creating a bias to attend and process external cues associated with reinforcement which are taken to control response-initiation rates.

Optimization of construction site layout using dynamic hybrid bacterial and ant colony algorithm

The efficient plan of site arrangement during the construction phase has been considered a vital duty to successful project performance due to the productivity enhancement as well as safety in executions. The optimization of the Construction Site Layout Problem (CSLP) is a combinatorial complexity that regards numerous objectives and considerable growth of scale as increasing of constraints and facilities. The rearrangement on site may thus need to be had dynamic plannings at several interval schedules as construction evolves to accommodate site needs. To resolve the complexity of this problem, many studies based on the Meta-heuristic approach have been done, there are however always drawbacks and should be improved to be more optimal. This research proposes a new Hybrid Meta-heuristic model which is a combination of Ant Colony Optimization algorithm (ACO), Bacterial foraging algorithm (BFA), and Pair-Wise Exchange Heuristic algorithm (PWEH). The proposed algorithm is named Dynamic Hybrid Ant Colony Algorithm (DHACA) model that can enhance local and global searches simultaneously. In addition, parameter values are optimized to create a better solution. This research also demonstrates the effectiveness of DHACA compared with the previous studies such as Multi-objectives Genetic Algorithm (MOGA), Simulated Annealing Algorithm based Multi-objectives Genetic Algorithm (SA-based MOGA) on the CSLP. DHACA supports the construction site dynamic planning with constraints on facilities to improve work efficiency.&#x0D;

Botulinum Injections for Idiopathic Cervical Dystonia: a Longitudinal Study.

Botulinum toxin (BT) injections into the cervical muscles are an effective and commonly practiced treatment approach for cervical dystonia. In this retrospective longitudinal study, we collected data from the Sheba electronic medical records on consecutive patients with idiopathic cervical dystonia (ICD), treated regularly with periodic BT injections between the years 2008-2020. All treatment visits were analyzed regarding type of toxin, dose injected, and clinical outcomes. The vast majority of patients were treated with abobotulinum toxin A. Sixty-four ICD patients (51 (79.7%) females, onset at age 45.8 ± 13.7years) were treated over 17.1 ± 13.9 (range 3 to 49) visits per patient; BT treatment efficacy increased gradually from initial treatment sessions to visit 13, when it achieved a steady state. While the subjective report of percentage improvement and its duration were around 78.9 ± 17.1% for 2.8 ± 1.0months, respectively, the dose of BT increased significantly over the years (p = 0.006). Side effects (SE) were not rare, and commonly recurred after subsequent sessions and were usually mild and short-lasting, with dysphagia being the most common (~17.5%), followed by neck/arm weakness (11.9%) and cervical pain (8.9%). Repeated injections of BT for ICD remain beneficial for patients over several years of therapy, and despite mild SE, patients tend to adhere to a 3-4months interval schedule.

Standard versus personalized schedule of regorafenib in metastatic gastrointestinal stromal tumors (GIST): A retrospective, multicenter, real-world study.

e23521 Background: Regorafenib (REG) is a multikinase inhibitor approved as third-line treatment in gastrointestinal stromal tumors (GIST). Although its proven activity, REG can present a relevant adverse profile which often leads to treatment modifications and transient or permanent discontinuation; thus, in clinical practice physicians usually adopt various dosing and interval schedules to counteract REG-related adverse events (AEs) and avoid treatment interruption. The aim of this real-world study was to investigate the efficacy and safety of personalized schedules of REG in metastatic GIST patients, in comparison with the standard schedule (160 mg daily, 3-weeks-on, 1-week-off schedule). Methods: Institutional registries across seven Italian reference centers were retrospectively reviewed and data of interest retrieved to identify GIST patients who had received REG from February 2013 to January 2021. The primary endpoint was Progression-Free Survival (PFS), with Overall Survival (OS) also assessed as secondary endpoint. The Kaplan-Meier method was used to estimate survival and the log-rank test to make comparisons. The impact of variables on survival was assessed through univariate and multivariate analysis. Results: A total of 152 GIST patients (82 male and 70 female) were included and split in two groups on the basis of the REG treatment plan received (standard vs personalized). Among the 103 patients for whom the treatment was personalized (38 since the beginning and 65 during the treatment course), the main strategies adopted were the following: 120 mg/day d1-21 e28 (n = 56; 54.4%); 80 mg/day d1-21 e28 (n = 22; 21.4%); 160 mg/day d1-5 e7 (n = 13; 12.6%). At a median follow-up of 36.5 months, median Overall Survival (OS) was 16.6 months (95% CI 14.1-21.8) and 20.5 months (95% CI 15.0-25.4) in the standard-dose and the personalized schedule groups, respectively (HR 0.75; 95% CI 0.49-1.22; p = 0.16). Median Progression-Free Survival (PFS) was 5.6 months (95% CI 3.3-not reached) and 9.7 months (95% CI 7.9-14.5) in the same groups (HR 0.51; 95% CI 0.34-0.75; p = 0.00052). Conclusions: Despite the expected limits of a retrospective analysis, we confirm that REG personalized schedules are commonly adopted in everyday clinical practice of high-volume GIST expert centers and correlate with significant improvement of therapeutic outcomes. Based on these results, REG treatment optimization in GIST patients may represent the best strategy to maximize long-term therapy, preserving tolerability and quality of life.

Machine Maintenance Planning in Manufacturing Company using RCM II Methods

Production machine is a crucial thing to be taken care of in order to keep the production flow stays in the right time, therefore maintenance management is needed. PT. XYZ is a manufacturing company that produces cables. One of the machines that are used and often experiences downtime is the drawing machine. Preventive Maintenance handling interval schedule could be designed by using Reliability Centered Maintenance II method. There are several ways for the data processing, which are FMEA calculation, RCM II Diagram Decision Worksheet, TTF and TTR parameter calculation, determining the correct distribution using Least Square Curve Fitting and Goodness of Fit, MTTF and MTTR calculation, reliability comparation between the conditions before and after the Preventive Maintenance is implemented, cost savings comparation between the condition before and after the maintenance is done. This research proves that interval 3 formulation with the Pay Off for 361 hours, Dancer for 327 hours, and Double Spooler for 174 hours would enhance the reliability of Pay Off to 52%, so could it to Dancer (to 57%) and Double Spooler (75%). It also proves that by implementing Preventive Maintenance with the formulated interval and the result of RCM II Decision Worksheet indicators would produce in cost savings for the Pay Off part to 25,96%, the Dancer to 35,1%, and Double Spooler to 53,52%.

Winter warm-up frequency and the degree of temperature fluctuations affect survival outcomes of spotted-wing drosophila winter morphotypes

Among overwintering Drosophila suzukii, discrete environmental changes in temperature and photoperiod induce a suite of biochemical changes conferring cold tolerance. However, little is known regarding how temperature fluctuations, which can influence metabolic and cellular repair activity, affect survival outcomes in this species. For that reason, we designed three experiments to test the effects of intermittent warm-up periods and the degree of temperature fluctuation on winter-morphotype (WM) D. suzukii survival. We found that at 5 °C, a temperature sufficient to induce reproductive diapause, but warm enough to allow foraging, increasing warm-up frequency (warmed to 25 °C at various interval schedules) was associated with decreased survival. In contrast, when the nightly low temperature was 0 °C, daily fluctuations that warmed the environment to temperatures above freezing (5, or 15 °C) appeared beneficial and resulted in improved survival compared to flies held at 0 °C during day and night. When we next evaluated cold tolerance using a 24-hour stress test assay (-5 °C), we found that again, thermal fluctuations improved survival compared to static freezing conditions. However, we also found that WM D. suzukii exposed to freezing temperatures during acclimation were less cold tolerant, regardless of the thermal fluctuation schedule, indicating that there may be tradeoffs between adequate acclimation temperature, which is required to induce cold tolerance, and the ensuing effects of incidental chill injury. Moving forward, these data, which account for the nuanced interactions between the thermal environment and in the internal physiology of D. suzukii, may help refine seasonal populations models, which aim to forecast pest pressure based on conditions the previous winter.

AN ADAPTIVE RESOURCE SCHEDULING FRAMEWORK WITH SCHEDULE INTERVAL FILLING FOR CLOUD SERVICES

Application level resource scheduling in distributed cloud computing is a significant research objective that grabbed the attention of many researchers in recent literature. Minimal resource scheduling failures, robust task completion and fair resource usage are the critical factors of the resource scheduling strategies. Hence, this manuscript proposed a scalable resource-scheduling model for distributed cloud computing environments that aimed to achieve the scheduling metrics. The proposed model called " Modified Resource Scheduling with Schedule Interval Filling " schedules the resource to respective task such that the optimal utilization of resource idle time achieved. The proposed model performs the scheduling in hierarchical order and they are optimal idle resource allocation, if no individual resource is found to allocate then it allocates optimal multiple idle resources with considerable schedule intervals filling. The experimental results evincing that the proposed model is scalable and robust under the adapted metrics.

Seroepidemiology of pertussis in China: A population-based, cross-sectional study

BackgroundDespite high pertussis vaccination coverage and significant decrease of pertussis since the adoption of the Expanded Programme on Immunization (1978), increased pertussis incidence has been reported in China from 2013 to 2017. This study aimed at evaluating the immune response to pertussis among vaccinated children and beyond in China. MethodsThe study recruited 2 144 healthy subjects. Serum IgG antibodies against pertussis toxin (anti-PT IgG) were measured by ELISA. Anti-PT IgG concentration (GMC), seropositivity rate (GMC ≥ 40 IU/ml), and recent infection rate (GMC > 100 IU/ml) were calculated. Participants ≤ 2 years-old were further stratified by vaccination schedule intervals and participants ≤ 6 years-old by vaccine used (Domestic DTaP or DTaP-IPV//PRP ~ T (Pentaxim, SP)). ResultsAmong 0–6-year-olds, the anti-PT IgG GMC was 5.99 IU/ml (95%CI 5.39–6.67). The GMC increased in accordance with the primary vaccination series (4–6 months) and the toddler booster (18–23 months), and continuously declined thereafter to its nadir at 6 years-old [3.72 IU/ml (95%CI 2.91–4.77)]. GMCs were markedly higher in those vaccinated with DTaP-IPV/PRP ~ T compared to DTaP. In individuals > 6 years-old, the GMC was 5.67 IU/ml (95%CI 5.36–6.00), the seropositivity rate was 6.7% (95%CI 5.5–7.9) and the recent infection rate was 1.2% (95%CI 0.7–1.7). The seropositivity rates increased from 6 years-old and peaked at 9 years-old (10.3% [95%CI 0.7–19.8]). ConclusionsVaccination against pertussis increases anti-PT IgG, but wanes over time. The sero-estimated infection rates increase from school age and peak at about 9 years-old. These results support the addition of a booster of pertussis vaccine at preschool age.

Effects of pre‐operant running and sucrose concentration on operant wheel running on a fixed interval schedule of reinforcement

Prior research proposed that temporal control over the pattern of operant wheel running on a fixed interval (FI) schedule of sucrose reinforcement is a function of automatic reinforcement generated by wheel running and the experimentally arranged sucrose reinforcement. Two experiments were conducted to assess this prediction. In the first experiment, rats ran for different durations (0, 30, 60, and 180 min) prior to a session of operant wheel running on a FI 120-s schedule. In the second experiment, the concentration of sucrose reinforcement on a FI 180-s schedule was varied across values of 0, 5, 15, and 25%. In Experiment 1, as the duration of pre-operant running increased, the postreinforcement pause before initiation of running lengthened while wheel revolutions in the latter part of the FI interval increased. In Experiment 2, wheel revolutions markedly increased then decreased to a plateau early in the FI interval. Neither manipulation increased temporal control of the pattern of wheel running. Instead, results indicate that operant wheel running is regulated by automatic reinforcement generated by wheel activity and an adjunctive pattern of running induced by the temporal presentation of sucrose. Furthermore, the findings question whether the sucrose contingency regulates wheel running as a reinforcing consequence.

COMPARING COORDINATED RESPONDING IN PAIRS OF RATS WHEN BOTH OPERANTS AND AGGREGATE PRODUCTS ARE SELECTED BY INTERMITTENT TEMPORAL CONSEQUENCES

Three pairs of rats worked in two adjacent operant chambers separated by a Plexiglas wall. In some experimental conditions, lever-presses were independent operants maintained by either a fixed-interval (FI) or variable interval (VI) schedule. In other conditions, each rat lever- press was part of two interlocked behavior contingencies as part of a metacontingency: its aggregate product, a brief flash of light, was maintained either by a FI or a VI schedule of mutual water presentation. The results clearly show that the interlocking of behavioral contingencies in the design of an experimental metacontingency established a pattern of cooperation between the rats.

Differential effects of photobiomodulation interval schedules on brain cytochrome c-oxidase and proto-oncogene expression.

.Significance: Transcranial photobiomodulation (PBM) is a noninvasive neuromodulation technique capable of producing changes in the mitochondrial cytochrome c-oxidase (CCO) activity of neurons. Although the application of PBM in clinical practice and as a neurophysiological tool is increasing, less is known about how different treatment time intervals may result in different outcomes.Aim: We evaluated the effects of different PBM treatment intervals on brain metabolic activity through the CCO and proto-oncogene expression (c-Fos).Approach: We studied PBM effects on brain CCO and c-Fos expression in three groups of animals: Control (CN, ), long interval PBM treatment (LI, ), and short interval PBM treatment (SI, ).Results: Increased CCO activity in the LI group, compared to the SI and CN groups, was found in the prefrontal cortices, dorsal and ventral striatum, and hippocampus. Regarding c-Fos expression, we found a significant increase in the SI group compared to LI and CN, whereas LI showed increased c-Fos expression compared to CN in the cingulate and infralimbic cortices.Conclusions: We show the effectiveness of different PBM interval schedules in increasing brain metabolic activity or proto-oncogene expression.

Instrumental behavior in humans is sensitive to the correlation between response rate and reward rate.

Recent theories of instrumental behavior postulate that the correlation between response and reward rate is a critical factor in instrumental goal-directed performance. However, it is still not clear whether human actions can be sensitive to rate correlation. Using a novel within-subject design, participants were trained under ratio and interval contingencies of reinforcement matching both reward probabilities and reward rates between conditions. The impact of rate correlation on performance was evident in the higher performance observed under ratio contingencies for both types of matching. Moreover, there was no difference in performance between two classes of interval schedules with equivalent correlational properties but different reward probabilities. These results are discussed in terms of a recent dual-system model of instrumental behavior.

Temporal contingencies are dependent on space location: Distal and proximal concurrent water schedules

Two studies evaluated the effect of delivering water depending on lever-pressing in a proximal or distant location to the water-producing response. Effects were measured on the spatial distribution of behavior and on the frequency and patterning of lever pressing. In both experiments water was available under two concurrent, complementary fixed interval schedules in two dispensers located at opposite ends of the chamber. The proportion of water deliveries in one dispenser relative to the second dispenser varied between phases, while the overall frequency was kept constant. In one study rats received water from a dispenser proximal to the water producing response location, whereas in the second study rats received water in the dispenser at the opposite panel where the response was emitted. The number of obtained water deliveries varied according to the programmed proportion, but rats obtained fewer deliveries under the distal location contingency. No systematic variations on space allocation were observed in neither experiment. The results are discussed in terms of the importance of considering the continuous interaction of time and space parameters in the analysis of behavior.

A theory of actions and habits: The interaction of rate correlation and contiguity systems in free-operant behavior.

Contemporary theories of instrumental performance assume that responding can be controlled by 2 behavioral systems, 1 goal-directed that encodes the outcome of an action, and 1 habitual that reinforces the response strength of the same action. Here we present a model of free-operant behavior in which goal-directed control is determined by the correlation between the rates of the action and the outcome whereas the total prediction error generated by contiguous reinforcement by the outcome controls habitual response strength. The outputs of these two systems summate to generate a total response strength. This cooperative model addresses the difference in the behavioral impact of ratio and interval schedules, the transition from goal-directed to habitual control with extended training, the persistence of goal-directed control under choice procedures and following extinction, among other phenomena. In these respects, this dual-system model is unique in its account of free-operant behavior. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Clinical effectiveness of different natalizumab interval dosing schedules in a large Italian population of patients with multiple sclerosis

IntroductionNatalizumab (NTZ) is one of the most effective treatment options for multiple sclerosis (MS) treatment. Our study aimed to evaluate the effectiveness of NTZ when administered according to the extended...

Rats exposed to intermittent ethanol during late adolescence exhibit enhanced habitual behavior following reward devaluation.

The brain undergoes substantial maturation during adolescence, and repeated exposure to ethanol at this time has been shown to result in long-lasting behavioral and neural consequences. During the broad period of adolescence, different neuronal populations and circuits are refined between early and late adolescence, suggesting the possibility that ethanol exposure at these differing times may lead to differential outcomes. The goal of the current study was to evaluate the impact of adolescent intermittent ethanol (AIE) during early and late adolescence on the formation of goal-directed and habitual behavior in adulthood. Male and female Sprague-Dawley rats were exposed to ethanol via intragastric gavage (4.0g/kg, 25% v/v) every other day from postnatal day (P) 25-45 or P45-65, considered early and late adolescence, respectively. In adulthood (~P70 early or~P90 late), rats were gradually food-restricted and began operant training on a fixed ratio 1 schedule. Rats were then transitioned onto random interval schedules and eventually underwent a sensory-specific satiation procedure as a model of reward devaluation. Few differences as a result of adolescent ethanol exposure were found during instrumental training. Following reward devaluation, rats exposed to water and ethanol during early adolescence exhibited reductions in lever pressing, suggestive of a goal-directed response pattern. In contrast, late AIE males and females demonstrated persistent responding following both devalued and non-devalued trials, findings representative of a habitual behavior pattern. The shifts from goal-directed to habitual behavior noted only following late AIE contribute to the growing literature identifying specific behavioral consequences as a result of ethanol exposure during distinct developmental periods within adolescence. More work is needed to determine whether the greater habit formation following late AIE is also associated with elevated habitual ethanol consumption.