Start Time Research Articles

The round start time effect: Start time roundness drives consumers’ willingness to participate

The round start time effect: Start time roundness drives consumers’ willingness to participate

Real-world Child-Pugh scores and outcomes of patients with hepatocellular carcinoma at a high-volume center.

569 Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and most often occurs in the setting of cirrhosis. Patients (pts) with advanced HCC are not eligible for curative intent therapies such as ablation, surgical resection, or liver transplantation. For the past five years, immune checkpoint inhibitor (ICI)-based systemic therapy regimens have been the mainstay of first-line treatment for pts with advanced HCC. Most trials assessing ICI-containing regimens, including IMBRAVE150 and HIMALAYA, excluded pts with Child-Pugh (CP) scores worse than A. Unfortunately, fewer than half of pts maintain a CP A score at the time of HCC diagnosis and referral to medical oncology. Real-world data on CP scores of patients undergoing ICI-based therapy for advanced HCC at the time of medical oncology referral and treatment start are lacking. Methods: Pts who initiated treatment with either atezolizumab plus bevacizumab (A+B) or durvalumab plus tremelimumab (D+T) in the Ochsner Health system between 1/1/20 and 12/31/23 were included in this analysis. CP scores were calculated at the time of their initial medical oncology visit and again at the time of their first systemic therapy cycle. Pt demographics and clinical outcomes were analyzed. Results: 200 pts were identified in this study, 159 of whom (79.5%) were male. Median age at treatment start was 66.8 years. 117 pts (58.5%) were Caucasian and 63 pts (31.5%) were African American (AA). 152 and 48 pts received A+B and D+T, respectively. At the time of first medical oncology visit, 58 pts (29%) were classified as CP B (n=51) or C (n=7). At the treatment start date, 82 pts (41%) were classified as CP B (n=73) or C (n=9). The median survival across all groups was 10.5 m. Median survival CP A, B, and C pts were 15.4, 7.6, and 1.6 months (m), respectively. 6-month survival rates for CP A, B, and C pts were 75.7%, 52.2%, and 0%, respectively. 12-month survival rates for CP A, B, and C pts were 58.2%, 35.1%, and 0%, respectively. There was no statistically significant difference in CP score at either time point between Caucasian and AA pts. Conclusions: Although pts with CP scores worse than A were not included in the pivotal studies that have established recent standard of care therapies for pts with advanced HCC, a significant proportion of pts being treated with ICI-based regimens have at least CP B liver disease, with a poorer prognosis in that subset of pts. Extremely poor survival rates for those with CP C scores argue against use of ICI-based treatment for these pts. In this analysis, no significant difference was observed in CP scores between Caucasian and AA pts.

Augmentation message design for LEO-enhanced precise positioning: In-orbit performance assessment

Recent advancements in low earth orbit (LEO) navigation augmentation systems, such as the CENTISPACETM system developed by Beijing Future Navigation Tech Co., Ltd, have significantly reduced the convergence time of GNSS precise point positioning (PPP). To facilitate LEO-enhanced precise positioning, we developed a comprehensive set of LEO augmentation messages, including GNSS/LEO state-space representation (SSR) parameters. These messages were validated through onboard tests using real LEO augmentation observations. To expedite cold start times, the GNSS orbit SSR is based on a polynomial model, while LEO orbits are modeled using classic GNSS broadcast ephemeris with additional perturbation parameters. GNSS and LEO clock are predicted by a linear model. The designed LEO augmentation messages were validated by LEO-augmented PPP calculations. The average convergence time with LEO SSR messages was 4.8 min, revealing an improvement of 71.3 % over GNSS PPP and aligning closely with the 5.1 min achieved through post-processing.

Rats and mice rapidly update timed behaviors

Keeping track of time intervals is a crucial aspect of behavior and cognition. Many theoretical models of how the brain times behavior make predictions for steady-state performance of well-learned intervals, but the rate of learning intervals in these models varies greatly, ranging from one-shot learning to learning over thousands of trials. Here, we explored how quickly rats and mice adapt to changes in interval durations using a serial fixed-interval task. In the first experiment, animals experienced randomly selected fixed-intervals of 12, 24, 36, 48, or 60 s, for blocks ranging from 13 to 21 trials. Consistent with previous work, animals abruptly increased lever pressing as reward availability approached, and these ‘start times’ scaled with the interval duration for both species. We then quantified the rate of updating to new trial durations and found that rodents consistently updated their start times within 2–3 trials following a change in interval duration, before stabilizing their behavior by the third or fourth trial. To account for repeated exposures to fixed-interval durations, a second set of animals was tested with new fixed-intervals after being trained on the serial fixed-interval task described above. Next, a third group was trained on fixed-interval durations that were generated de novo in each day. In each of these contexts, rodents rapidly increased or decreased their start times to mirror new FI durations following exposure to 1–2 trials of new intervals following block transitions. This work adds to growing evidence for rapid duration learning across species, highlighting the need for timing models to be capable of rapid updating in dynamic temporal scenarios.

Fast and fair randomized wait-free locks

Abstract We present a randomized approach for wait-free locks with strong bounds on time and fairness in a context in which any process can be arbitrarily delayed. Our approach supports a tryLock operation that is given a set of locks, and code to run when all the locks are acquired. A tryLock operation may fail if there is contention on the locks, in which case the code is not run. Given an upper bound $$\kappa $$ κ known to the algorithm on the point contention of any lock, and an upper bound L on the number of locks in a tryLock’s set, a tryLock will succeed in acquiring its locks and running the code with probability at least $$1/(\kappa L)$$ 1 / ( κ L ) . It is thus fair. Furthermore, if the maximum step complexity for the code in any lock is T, the operation will take $$O(\kappa ^2 L^2 T)$$ O ( κ 2 L 2 T ) steps, regardless of whether it succeeds or fails. The operations are independent, thus if the tryLock is repeatedly retried on failure, it will succeed in $$O(\kappa ^3 L^3 T)$$ O ( κ 3 L 3 T ) expected steps. If the algorithm does not know the bounds $$\kappa $$ κ and L, we present a variant that can guarantee a probability of at least $$1/\kappa L\log (\kappa L T)$$ 1 / κ L log ( κ L T ) of success. We assume an oblivious adversarial scheduler, which does not make decisions based on the operations, but can predetermine any schedule for the processes, which is unknown to our algorithm. Furthermore, to account for applications that change their future requests based on the results of previous tryLock operations, we strengthen the adversary by allowing decisions of the start times and lock sets of tryLock operations to be made adaptively, given the history of the execution so far.

Butorphanol Tartrate Nasal Spray for Post-Cesarean Analgesia and Prolactin Secretion.

BACKGROUND Butorphanol, an opioid receptor agonist and antagonist, is widely used for post-cesarean section analgesia in the form of intravenous or intramuscular injection, but nasal sprays are less used. This study aimed to evaluate the analgesic effect of butorphanol nasal spray on uterine contraction pain after cesarean section and explore its effect on postpartum prolactin secretion. MATERIAL AND METHODS We randomly divided 120 patients scheduled for cesarean section into 3 groups (40 per group): intranasal saline (control), butorphanol intranasal (BI), and butorphanol pumped intravenously (BV). The same analgesic pump protocol was used in all groups. The visual analog scale (VAS) and Ramsay sedation scale (RASS) were used to evaluate analgesic and sedation levels 6, 12, and 24 h postoperatively. We recorded the start time of breastfeeding, number of PCIA presses, consumption of butorphanol, and preoperative and postoperative serum prolactin levels. RESULTS At 6 h postoperatively, the BI and BV groups had lower VAS and higher RASS (P<0.05) than the control group, no difference between the BI and BV groups, but the consumption of butorphanol was lower in the BI group (P<0.05). The analgesic and sedative effects in the BI group were lower than those in the BV group at 12 h (P<0.05). No difference in the start time of breastfeeding, serum prolactin levels among the 3 groups (P>0.05). CONCLUSIONS Patients may prefer butorphanol tartrate nasal spray because they can obtain satisfactory analgesia in the early postoperative period, with high non-invasive comfort and reduced use of opioids. No effect on prolactin levels or lactation initiation was observed.

Numerical solution of a nonlinear model of chromatography considering different isotherms and gradient profiles

In gradient chromatography, the mobile phase composition is progressively altered to regulate the propagation rates of the injected mixture components. Resultantly, improved separation of mixture components can be attained, the recycling time that must pass between two consecutive injections can be reduced, and, hence, the column’s efficiency and selectivity can be enhanced. A coupled modeling framework, integrating a lumped kinetic model and the convection–diffusion equation for solvent volume fraction, is employed to approximate the process. The influence of different isotherm models on the process dynamics is examined through numerical simulations. A semi-discrete second-order finite volume scheme is suggested to approximate the model equations. Impacts of positive and negative gradients, gradient shapes, gradient starting and ending times, axial dispersion, Henry’s constants, nonlinearity coefficients, mass transfer coefficients, and different adsorption isotherms are investigated. The theoretical findings presented in this study may facilitate further advancements in the field of gradient elution chromatography.

The Effect of Resistance Strength Training on Muscle Cross Education: A Meta analysis

Introduction: At present, a large number of studies have found that the phenomenon of cross transfer has achieved significant research results in sports training, rehabilitation therapy, and influencing mechanisms. Cross training refers to increasing muscle strength on the training side, while there is also a significant increase in muscle strength on the untrained homologous side. The main purpose of this review is to explore the impact mechanism of cross transfer phenomenon and summarize the optimal training methods and rehabilitation methods for cross transfer phenomenon. Aim of the study: Using meta-analysis method to systematically evaluate the effects of cross training (also known as cross education) on upper and lower limb muscle strength in different age groups and compare the training results. Material and methods: The system searched databases such as Wanfang Digital Resource Database, China National Knowledge Infrastructure Database, EBSCOhost, PubMed, Web of Science, and Cochrane Library from the default start time to December 2024. Two evaluators independently screened research literature on resistance strength training improving upper and lower limb muscle strength and hypertrophy in various age groups based on inclusion and exclusion criteria. Revmen 5.3 was used to evaluate all included literature and analyze their data. Result: 1)After 4 rounds of exclusion, 7 articles were finally included with a total sample size of 257 people; 2) Cross education intervention under resistance strength training can significantly enhance the strength of the quadriceps muscle in adults, with better results than the control group. The combined effect size is SMD=8.03, 95% CI:- 1.32，17.37， P＜0.01， 3) The degree to which cross education intervention enhances the strength of the gastrocnemius and wrist extensor muscles under resistance strength training is similar. The combined effect quantities are: SMD＝0.17，95% CI：-2.28，2.62，P≥0.01； SMD＝-0.39，95% CI：-3.02，2.25，P≥0.01； SMD=0.20, 95% CI: -0.81, 1.21, P ≥ 0.01 Conclusion: Cross education intervention under resistance strength training can significantly improve quadriceps strength and promote muscle hypertrophy in adults; The effect of cross education intervention under resistance force on promoting the strength and hypertrophy of the gastrocnemius muscle and wrist extensor muscle is similar.

The efficacy of ultrasound-assisted pterygopalatine blockade by the posterior-anterior infrazygomatic approach during eye enucleation: prospective randomized comparative study

BACKGROUND: The pterygopalatine blockade (PPB) has broad indications in ophthalmology, which explains the possibility of simultaneous influence on sympathetic, parasympathetic and nociceptive innervation. Ultrasound navigation is widely used to control blockades, but currently there is no information on the clinical efficacy of performing ultrasound-assisted pterygopalatine blockade with different access. OBJECTIVE: Our aim was to compare the efficacy of performing ultrasound-navigated PPB with by posterior-anterior infrazygomatic and supra-zygomatic approaches in patients after eye enucleation. MATERIALS AND METHODS: A prospective randomized study was conducted. For postoperative anesthesia in group 1 PPB was performed using a posterior-anterior infrazygomatic approach (n=30), in group 2 (n=30) — using a supra-zygomatic approach. The time of PPB performance, the anesthesia start time, changes in blood pressure and heart rate as well as technical features of the blockade were evaluated. RESULTS: A comparison of the time interval from the blockade performance to the anesthesia start time in the groups demonstarted that in patients of group 1 it was 5.3±1.0min., which had significant differences with the results in group 2 — 10.1±1.4min. (p=0.041). When comparing the dynamics of the onset of the analgesic effect, the PPB demonstrated that in patients of group 1, the time for the onset of anesthesia was 5.3±1.0min., compared with the results of group 2 — 10.1±1.4min. (p=0.041). A statistically significant difference was found in the time of onset of a skin sensitivity decrease in the suborbital region and the time required for a pain syndrome relief: in group 1 — 8.9±0.9min. and 13.5±0.7min., in group 2 — 14.4 ±1.2min. and 19.6±1.7min., respectively (p=0.037, p=0.034). The PPB values in patients of group 1 were 91.2±6.5mmHg significantly lower compared with the values of patients of group 2 — 101.1±6.6mmHg, respectively (p=0.001). When performing PPB by the supra-zygomatic approach (group 2), in 53.3% (n=16) of cases patients reacted to painful sensations, the average score for PPB was 2.3±0.5. CONCLUSION: In the treatment of pain syndrome after enucleation of the eye, the method of choice is ultrasound-assisted PPB blockade by the posterior-anterior infrazygomatic approach, which, in comparison with the blockade by the supra-zygomatic approach, ensures the rapid start of effective analgesia, comfort and safety for the patient.

Deep reinforcement learning for Agile Earth Observation Satellites scheduling problem with variable image duration

The Agile Earth Observation Satellites (AEOS) possess active imaging capabilities, which enable variable image durations during observations. Due to the problem’s high complexity, traditional heuristic algorithms are unable to provide optimal solutions within a feasible timeframe. In this paper, we propose an improved deep reinforcement learning approach (IDRL), including IDRL based on optimal observation quality (IDRL-MQ) and IDRL based on the longest observation duration (IDRL-MD), to solve the multi-objective scheduling problem for AEOS with variable image duration (MO-SPVID). Two different strategies IDRL-MQ and IDRL-MD, were designed to determine the start time and duration of observation. The experimental results demonstrate that IDRL-MD outperforms both IDRL-MQ and the superior heuristic algorithm ALNS-NSGAII in terms of solution quality and solution diversity. The demonstrated effectiveness of the appropriate heuristic strategies provides evidence for their rationality. Furthermore, the results obtained on instances of varying scales indicate that IDRL exhibits a high level of generality and robustness.

A novel data source for human-caused wildfires in China: extracting information from judgment documents

Information on the spatiotemporal distribution of human-caused wildfires on a national scale is crucial for developing susceptibility map and facilitating decision-making in fire risk management. In China, it is difficult to access a national dataset of wildfires based on ground records at a fine spatiotemporal scale for understanding fire regimes. This study explores the use of judgment documents as a potential alternative long-term key data source, considering human-caused wildfire events as criminal offense in certain cases. Judgment documents are readily accessible, regularly updated, and provide a diverse range of reliable information. To extract information on human-caused wildfires, we develop a rule-based approach for judgment documents. The results indicate the feasibility of the method, allowing for the effective extraction of specific information of event such as the start date and time, location, burn area, and ignition cause. A comparison reveals limited consistency in the spatiotemporal distributions between the novel data and conventional datasets. Notably, judgment documents provide richer attribute information and identify additional human-caused wildfires challenging to capture using conventional datasets. Despite inherent limitations, information sourced from judgment documents proves valuable data for characterizing national patterns of wildfire occurrence at a fine scale.

Determining the Starting Time of CO2 Injection and Its Implications for the CO2-ECBM Process.

Determining the starting time of the CO2 injection is the key factor affecting the effect of CO2 injection and CH4 production. This study uses the Panyidong mine in the Huainan mining area as an example. First, fully coupled mathematical models are established. Second, the evolution law of the reservoir parameters under different starting times of CO2 injection is visualized. Then, the starting time of the CO2 injection is determined, and the transformation process of CH4 displaced by CO2 is discussed. Finally, the connotation of the continuous fluid process during the CO2-ECBM process is analyzed, and constructive suggestions for CO2 injection are presented. The results show that during the CO2-ECBM process, the reservoir pressure and gas content greatly change near the CO2 injection well, and gradually decrease near the CH4 production well. The competitive adsorption of the gas is exothermic, and the reservoir temperature gradually increases. The competitive adsorption of gas causes matrix expansion, which results in a decrease in permeability. The CH4 production rate can be increased by about 2 times, and the evolution law of the CO2 injection rate shows little difference. If the purpose of CO2 injection is to store CO2, the start time of CO2 injection may be set as the 2000th day. The CO2-ECBM process can be divided into three stages to characterize the importance of displacement and replacement effects in each stage. Determining the starting time of CO2 injection and giving more desorption time to CH4 is conducive to the expansion of pore and fracture spaces, and then gives more competitive adsorption time to gas. This study can promote the engineering implementation of the CO2-ECBM technology.

An Ontology-Based Approach for Understanding Appendicectomy Processes and Associated Resources.

Traditional methods for analysing surgical processes often fall short in capturing the intricate interconnectedness between clinical procedures, their execution sequences, and associated resources such as hospital infrastructure, staff, and protocols. This study addresses this gap by developing an ontology for appendicectomy, a computational model that comprehensively represents appendicectomy processes and their resource dependencies to support informed decision making and optimise appendicectomy healthcare delivery. The ontology was developed using the NeON methodology, drawing knowledge from existing ontologies, scholarly literature, and de-identified patient data from local hospitals. The resulting ontology comprises 108 classes, including 11 top-level classes and 96 subclasses organised across five hierarchical levels. The 11 top-level classes include "clinical procedure", "appendicectomy-related organisational protocols", "disease", "start time", "end time", "duration", "appendicectomy outcomes", "hospital infrastructure", "hospital staff", "patient", and "patient demographics". Additionally, the ontology includes 77 object and data properties to define relationships and attributes. The ontology offers a semantic, computable framework for encoding appendicectomy-specific clinical procedures and their associated resources. By systematically representing this knowledge, this study establishes a foundation for enhancing clinical decision making, improving data integration, and ultimately advancing patient care. Future research can leverage this ontology to optimise healthcare workflows and outcomes in appendicectomy management.

Robotic versus laparoscopic intersphincteric resection for patients with low rectal cancer: Short-term outcomes.

This study aimed to evaluate the short-term outcomes between laparoscopic intersphincteric resection (L-ISR) and robotic intersphincteric resection (R-ISR) for low rectal cancer. We performed a retrospective clinical analysis between August 2018 and August 2021 at the Department Of General Surgery, the Affiliated Hospital of Nanjing University Medical School. A total of 28 patients were recruited in this research. Among these patients, there were 12 patients who underwent L-ISR and assigned to L-ISR group, and the remaining 16 patients underwent R-ISR and assigned to R-ISR group. The time to start oral fluids, time to start soft diet and time to first motion in R-ISR group were earlier than those in L-ISR group ( P < 0.05). The hospital stay in R-ISR group was shorter than that in L-ISR group ( P < 0.05). However, the operation time of R-ISR was longer compared to L-ISR group ( P < 0.05). Most important of all, the Kelly score in R-ISR group was 5.1 ± 0.9, which was higher than that in L-ISR group ( P = 0.004). R-ISR is safe and feasible for patients with low rectal cancer. R-ISR is superior to L-ISR despite the operation time of R-ISR is longer. A randomised controlled trial will be performed to confirm the conclusion further.

The Role of WISHE in the Rapid Intensification of Super Typhoon Hinnamnor (2022)

AbstractIn this study, the role of the wind‐induced surface heat exchange (WISHE) in rapid intensification (RI) is investigated in a numerical model. During the development of Hinnamnor, its energy growth rate (EGR) continuously increases as RI progresses. After Hinnamnor reaches its maximum intensity, although its EGR weakens a little, it remains relatively large. If it had not been for the influence of the external environment (such as the tropical depression), its maximum intensity would have been far greater than the actual maximum intensity (140 knots). As the WISHE effect progressively weakens, the number of convective bursts (CBs) gradually diminishes. This, in turn, gives rise to a corresponding weakening of the warm core and a subsequent delay in the start time of the axisymmetrization of the inner core, thereby affecting the intensification rate of the vortex and the final maximum intensity. Consequently, the start time of RI is also correspondingly postponed. Differing from the maximum potential intensity theory, when the EGR approaches zero, a TC does not immediately reach its maximum intensity. Instead, it attains its peak intensity approximately 12 hr later. During this additional 12 hr period, the number of CBs continues to increase, the warm core keeps on strengthening and the inner core continues its progress toward axisymmetric until the end of the RI process. This indicates that the dynamical and thermodynamical processes are also of great importance during the RI stage.

Matching Methods of Shared Parking Slots Considering Overdue Parking Behavior

With the continuous increase in the number of vehicles worldwide, parking challenges have become more severe, making it a shared goal for governments to alleviate parking difficulties in urban centers. Shared parking has emerged as an effective solution to address parking problems and has been widely studied in recent years. However, existing research primarily focuses on static or single-period parking matching, often neglecting the conflicts between overdue parking users and subsequent users. Therefore, addressing the impact of overdue parking on shared parking systems is highly important. This study proposes a multi-period dynamic matching decision model (MDMD), which divides the operation period of the shared parking platform into multiple decision points. At each decision point, parking demands are classified into four categories: newly arriving demands, allocated demands with a start time not within the current decision point, overdue demands during the current decision point, and demands affected by overdue parking. Three decision variables are established to determine matching schemes for the first, second, and fourth types of parking demands, facilitating a dynamic decision-making process that effectively mitigates the impact of overdue parking. A corresponding algorithm is designed to solve the model. Since the single-period model is a linear programming model, the CPLEX solver obtains allocation schemes for each decision point. These schemes, along with new parking demands, are used as input for the next decision point, achieving a dynamic matching process. Simulation experiments are conducted to compare the MDMD model with the traditional First-Book-First-Served (FBFS) model based on platform revenue, parking space utilization, and parking demand acceptance rate. The experimental results show that, compared to FBFS, MDMD improves long-term earnings by 83%, actual profits in recent profits by 6.6%, and parking space utilization by 8% while maintaining a similar parking demand acceptance rate. To validate the robustness of the model, additional simulations are performed under various overdue probability scenarios, demonstrating that MDMD maintains stable system performance across different probabilities. These improvements highlight the advantages of the dynamic matching strategy, distinguishing this study from existing methods lacking adaptability. These findings provide valuable insights for the optimization of shared parking systems, contributing to sustainable transportation solutions and efficient urban mobility management.

Efficacy of preemptive multimodal analgesia initiated at various time points before total knee arthroplasty: a prospective, double-blind randomized controlled trial.

Preemptive multimodal analgesia (PMA) is commonly employed for pain control after total knee arthroplasty (TKA). However, the optimal timing for initiating PMA remains unclear. This study aimed to compare the efficacy of PMA administered at different time points before TKA. In this prospective, double-blind, placebo-controlled, randomized trial, 120 patients who underwent TKA were randomized into three groups. PMA (200mg celecoxib and 150mg pregabalin administered every 12h) was initiated 48h (group A), 24h (group B), and 1h (group C) before surgery. The primary outcome was the postoperative administration of morphine hydrochloride as a rescue analgesic. Secondary outcomes included time to first rescue analgesia, postoperative pain assessed using the visual analog scale (VAS), functional recovery assessed by knee motion range and ambulation distance, time until hospital discharge, and complication rates. Compared with group C, groups A and B exhibited significantly lower morphine consumption within 24h after surgery, lower total morphine consumption, longer time to first rescue analgesia, and superior range of knee motion on the day of surgery. Groups A and B did not exhibit significant differences in these outcomes. The three groups did not differ significantly in postoperative VAS pain scores, ambulation distance, length of hospital stay, or complication rates. In comparison with PMA starting at 1h preoperatively, initiating PMA at 24 and 48h preoperatively provided better postoperative pain relief. Considering the aim of minimizing the amount of ineffective medication received by patients, initiating PMA at 24h preoperatively may be a more favorable option for patients undergoing TKA. However, the clinical significance of our results and the optimal starting time for PMA require further investigation.

BALANCING SCHOOL DURATION AND HEALTH: IMPACTS ON STUDENTS' WELL-BEING AND POLICY INSIGHTS

The length of school hours has a significant impact on students' physical and mental health, raising concerns about balancing academic demands with well-being. In countries like Indonesia, long school hours often lead to issues like fatigue, stress, and poor nutrition. Conversely, countries with shorter school days, such as Finland, show better health outcomes. This study aims to explore the relationship between school hours and student health, providing evidence-based recommendations for education policy reform. Its innovative approach compares different cultural and educational contexts, including Indonesia, to highlight region-specific effects. Using qualitative methods, the research involved interviews, observations, and document analysis, gathering data from students, parents, and teachers. Findings suggest that longer school hours negatively affect physical activity, sleep, and overall well-being, while shorter hours and later start times improve mental health and academic engagement. Indonesia’s Karja Sezi program demonstrates the effectiveness of policies, like regulated meals, in reducing health risks. This study contributes to discussions on education and health, offering actionable insights for policymakers to create balanced school schedules that support both academic success and student well-being.

Antivirals in Preventing Perinatal Transmission of Hepatitis B: Start and Stop Times are Shifting.

Antivirals in Preventing Perinatal Transmission of Hepatitis B: Start and Stop Times are Shifting.

The role of promotions and other factors in attendance for minor league baseball – a study across all levels of play

PurposeThe main purpose of this research was to determine what types of promotions increase Minor League Baseball attendance across all of the official leagues. The secondary purpose was to ascertain the role of other control variables such as win percentage, weather, days of the week, start time and city demographics. The research also includes a grouping of cities through k-means clustering to better understand what types of promotions work in what cities.Design/methodology/approachData were gathered on all the Minor League Baseball teams and their respective cities. Regression models were run to test for the role of individual promotions (structured as dummy variables) and other controls. One model specification used city demographic variables, one used city fixed effects rather than city demographics and the final specification used k-means clustering to separate cities into distinct groups.FindingsPromotions generally were found to increase attendance, although there were differences across levels of play. K-means clustering helped with the grouping of cities to ascertain which types of promotions were beneficial when comparing large metropolitan areas to high-income cities.Research limitations/implicationsPromotions were grouped into common categories, although some were difficult to classify (or were infrequent), so a miscellaneous promotions category was included to capture these promotions in Minor League Baseball.Practical implicationsThe findings of this research are beneficial to those designing promotional schedules for individual teams. It also is beneficial to the leagues as the findings have implications as it relates to what fans desire to see when attending minor league games.Originality/valueThe originality in this work is the collection of all Minor League Baseball attendance, city information and promotional information across the different levels of play (AAA, AA, High-A and A). Using different model specifications and groupings, including k-means clustering to match similar cities, successful promotions were identified.