Scheduled Ones Research Articles

The clinical practice and dosimetric outcome of the manual adaptive planning during definitive radiotherapy for cervical cancer

ProposeTo evaluate the advantage of the manual adaptive plans comparing to the scheduled plans, and explored clinical factors predicting patients suitable for adaptive strategy.Methods and materialsEighty two patients with weekly online cone-beam computed tomography (CBCT) were enrolled. The re-CT simulation was performed after 15 fractions and a manual adaptive plan was developed if a significant deviation of the planning target volume (PTV) was found. To evaluate the dosimetric benefit, D98, homogeneity index (HI) and conformity index (CI) for the planning target volume (PTV), as well as D2cc of the bowel, bladder, sigmoid and rectum were compared between manual adaptive plans and scheduled ones. The clinical factors influencing target motion during radiotherapy were analyzed by chi-square test and logistic regression analysis.ResultsThe CI and HI of the manual adaptive plans were significantly superior to the scheduled ones (P = 0.0002, 0.003, respectively), demonstrating a better dose coverage of the target volume. Compared to the scheduled plans, D98 of the manual adaptive plans increased by 3.3% (P = 0.0002), the average of D2cc to the rectum, bladder decreased 0.358 Gy (P = 0.000034) and 0.240 Gy (P = 0.03), respectively. In addition, the chi-square test demonstrated that age, primary tumor volume, and parametrial infiltration were the clinical factors influencing target motion during radiotherapy. Multivariate analysis further identified the large tumor volume (≥ 50cm3, OR = 3.254, P = 0.039) and parametrial infiltration (OR = 3.376, P = 0.018) as the independent risk factors.ConclusionWe found the most significant organ motion happened after 15 fractions during treatment. The manual adaptive plans improved the dose coverage and decreased the OAR doses. Patients with bulky mass or with parametrial infiltration were highly suggested to adaptive strategy during definitive radiotherapy due to the significant organ motion.

Emergencies in occupational medicine: the experience of an on-site medical office

Abstract Objective : Medical emergencies (ME) in the occupational medicine (OM) office represent an increasingly frequent challenge, because they may require treatment or an ambulance, involving monitoring the patient, halting scheduled activity. The objective of this retrospective observational study was to study ME in the on-site medical office of a local pharmaceutical company, with an emphasis on the differences between major and minor emergencies, and on the factors associated with a longer duration of consultations, in order to optimize management. Methods : ME in the on-site office of a local company, January - June 2023 (109 working days), were recorded. The presentations were divided into 2 groups (G): G1 - ME that required ambulance/hospitalization/immediate treatment (etiological and/or symptomatic) and G2 - ME without immediate intervention. Results : During the 109 working days analyzed, 173 consultations involved ME (12.5% of the total presentations), with a mean of 1.6 presentations/day, On the 62 days with ME, the average was 2.7 presentations/day. The presentations, with a mean age of 40.8 years and a female predominance (69.4%), were divided into 2 groups: G1 included 95 (54.9%) presentations with immediate intervention, G2 - 78 (45.1%). In G1, 8 (8.4%) presentations required ambulance to hospital, 39 (41.1%) received etiological treatment, and 76 (81.1%) symptomatic treatment. Presentations for infectious diseases in a pandemic context ranked first This emphasizes the role of the OM physician in assessing Covid-19 contacts/patients. An ME consultation lasted on average 16.2 minutes, with a maximum of 19.4 minutes (excluding Covid-19 rapid testing). The most frequent ME complaints/humors were of cardiovascular, neurological, digestive and musculoskeletal origin. The maximum duration was in cardiovascular disease, associated with each type of intervention (p<0.0001 in the 3 cases: ambulatory/symptomatic/etiological treatment). Conclusion : ME in the OM doctor’ activity are frequent, more so in middle-aged women, especially between 12:01-16:00. They add approximately 2-3 consultations daily, in addition to the scheduled ones (30-45 additional minutes). Most ME require medical intervention: treatment in the office/ambulance. Apart from the COVID-19 context, most ME were cardiovascular (most time-consuming), digestive, neurological, and musculoskeletal. The duration of emergency consultations, additional to appointments, could require dedicated intervals, in order not to overload the physician. A systematized analysis of ME, paralleled by a good feedback towards the employer, could favor an individualized approach and an optimized endowment of the office, allowing identification of undiagnosed chronic disease, which would enhance productivity.

The Clinical Practice and Dosimetric Outcome of the Manual Adaptive Planning during Definitive Radiotherapy Treatment for Cervical Cancer

Organ motion is challenging during primary definitive external beam radiotherapy in locally advanced cervical cancer (LACC). Our study evaluated the manual adaptive planning approach three weeks after the treatment started, compared the dosimetric consequences of the manual adaptive plans to the scheduled plans, and explored the clinical factors predicting patients suitable for this replanning strategy. We analyzed 82 patients receiving primary definitive external beam radiotherapy with weekly online cone-beam computed tomography (CBCT)-based monitoring. The re-CT simulation was performed during treatment to develop a new plan (manual adaptive plan) due to a significant deviation of the clinical target volume (CTV). To evaluate the dosimetric benefit, D98, homogeneity index (HI) and conformity index (CI) for the planning target volume (PTV), as well as D2cc of the bowel, bladder, sigmoid and rectum were compared between the manual adaptive plans and the scheduled ones. The clinical factors influencing target motion throughout treatment were analyzed by chi-square test and logistic regression analysis. The re-CT simulation was performed after 15 fractions during treatment to develop the manual adaptive plan in 41 patients. The median CI and HI of the manual adaptive plan were significantly superior to the scheduled one (P = 0.001, 0.003, respectively), demonstrating a better dose coverage of the target volume. Compared to the scheduled plans, D98 of the manual adaptive plans increased by 3.3% (P = 0.0002), the average of D2cc to the rectum, bladder decreased 0.267Gy (P = 0.0049) and 0.321Gy (P = 0.0146), respectively. In addition, the chi-square test demonstrated that age (P = 0.024), primary tumor volume (P = 0.015), and parametrial infiltration (P = 0.022) were the clinical factors influencing target motion throughout treatment. Multivariate analysis further identified the large tumor volume (≥50cm3, OR = 3.254, P = 0.039) and parametrial infiltration (OR = 3.376, P = 0.018) as the independent risk factors. We found the most significant organ motion happened after 15 fractions during treatment. The manual adaptive planning of definitive radiotherapy improved the dose coverage and decreased the volume of organs at risk of receiving clinically significant doses of RT in patients with LACC. Patients with bulky mass or with parametrial infiltration were highly suggested to receive manual adaptive planning after 15 fractions during definitive radiotherapy, a timesaving strategy compared to the daily online adaptive radiotherapy without compromising the target dose coverage.

Optimization of Monitoring of Apron Cleanliness from Foreign Object Debris (FOD) by the Apron Movement Control Unit (AMC) at Supadio Pontianak International Airport

Foreign Object Debris (FOD) is an object or foreign object that is alive or not living in the apron area (aircraft parking area), taxiway and runway (runway) which can cause damage to aircraft and has the potential to pose a hazard to the safety and security of aircraft operations fly. The purpose of this study was to determine the efforts, constraints, and solutions of Apron Movement Control (AMC) officers in monitoring the cleanliness of aprons from Foreign Object Debris (FOD) at Supadio Pontianak International Airport. This study used a qualitative research method using primary and secondary data which was conducted in March 2023 at Supadio Pontianak International Airport. This research was conducted in the Apron Movement Control and Ground Handling units using data collection and retrieval techniques through interviews conducted with 1 resource person from the Apron Movement Control Coordinator, 1 marshaller from PT. Mulio Citra Angkasa as the Ground Handling Agent, through observation, documentation and library research. To test the validity of the data, researchers used credibility, transferability, dependability, and confirmability tests. As for data analysis that researchers use, namely data collection, data reduction, data presentation, verification and conclusions. The results of this study indicate that AMC officers make efforts to monitor the cleanliness of the apron by carrying out scheduled inspections, outside of the scheduled ones, and coordinating with related stake holders such as ground handling, bukaka, and Pertamina. The obstacle faced by AMC officers is the number of officers who are only 2 to 3 people per shift makes it difficult for officers to carry out supervision on the apron, the condition of the apron is cracked, and the construction of new corridors so that it is feared that it can cause FOD to enter the apron. The solution to deal with these obstacles is to carry out routine inspections at least 2 times per shift and additional inspections if the weather is bad, conduct socialization to increase awareness of all stakeholders at the airport, conduct FOD Walks when AMC officers want to operate garbarata.

Effective league championship algorithm and lower bound procedure for scheduling a single batch-processing machine with non-identical job sizes and job rejection

We address the scheduling problem of a set of non-identical size jobs on a single batch-processing machine (SBPM) wherein the scheduler can make decision whether to schedule a job in batches or not to schedule it with a job-dependent penalty. The processing time of a batch is the greatest job processing time in that batch (parallel batching or p-batching). The scheduler wants to minimize a given objective function f, where f is the total rejection penalties of the rejected jobs (rejection cost) plus the makespan of the scheduled ones. We formulate the aforementioned problem as a 0–1 mixed integer programming model. We also apply an effective dynamic programming algorithm (DPA) to calculate a lower bound (LB) on the optimal cost of the problem. To tackle the problem, we propose a grouping algorithm, based on league championship algorithm (LCA), with new updating equations maintaining the major characteristics of the original updating equations of the LCA and well-suited to the structure of the problem. For small problems, performance of the proposed LCA is compared with GAMS/CPLEX solver. For large-scale instances, a genetic algorithm is adopted as a basis for comparison. Simulated experiments confirm the performance of the proposed methods.

Acute Mechanical and Metabolic Responses to Different Resistance Training Protocols With Equated Volume Load.

To investigate the effect of different resistance training protocols with equated volume load on acute mechanical and metabolic responses. In a randomized order, 18 men performed 8 different training protocols in the bench press exercise consisting of (sets, repetitions, intensity, and interset recoveries) 3 × 16, 40% 1-repetition maximum (1RM), 2 and 5minutes; 6 × 8, 40% 1RM, 2 and 5minutes; 3 × 8, 80% 1RM, 2 and 5minutes; and 6 × 4, 80% 1RM, 2 and 5minutes. Volume load was equalized between protocols (1920arbitrary units). Velocity loss and effort index were calculated during the session. Movement velocity against the 60% 1RM and blood lactate concentration pre-post exercise were used to assess the mechanical and metabolic responses, respectively. Resistance training protocols performed with heavy load (80% 1RM) resulted in a lower (P < .05) total number of repetitions (effect size = -2.44) and volume load (effect size = -1.79) than the scheduled ones when longer set configurations and shorter rest periods were used in the same protocol (ie,higher-training-density protocols). Protocols including a higher number of repetitions per set and shorter rest times induced higher velocity loss, effort index, and lactate concentrations than the rest of the protocols. Our results suggest that resistance training protocols with similar volume load but different training variables (ie,intensity, number of sets and repetitions, rest between sets) produce different responses. Implementing a lower number of repetitions per set and longer rest intervals is recommended to reduce the intrasession and postsession fatigue.

Utility of 1,2-o-dilauryl-rac-glyceroglutaric acid-(6'-methylresorufin)-ester-lipase for monitoring dogs with chronic pancreatitis.

The utility of 1,2-o-dilauryl-rac-glycero glutaric acid-(6'-methylresorufin)-ester-(DGGR)-lipase activity (DLA) in monitoring clinical progression of chronic pancreatitis (CP) in dogs is unknown. To examine the association of DLA with clinical signs of CP, as assessed by a CP clinical severity score (CPCSS). Twenty-four dogs. This is a retrospective study. Chronic pancreatitis was diagnosed based on clinical signs and DLA > 250 U/L and monitored using CPCSS and DLA. The study included 134 visits (median, 10 visits/dog; range, 2-11). Mild-moderate (CPCSS, 0-3) and severe (CPCSS, ≥4) disease were documented in 94 (70%) and 40 (30%) visits, respectively. In emergency visits (n=44; 33%) CPCSS (median, 5; range, 0-15) and DLA (median, 534 U/L; range, 63-7133) were higher (P< .001 and P= .003, respectively) than in scheduled ones (n=90; 67%; median, 1; range, 0-6 and median, 384 U/L; range, 49-3747, respectively). DGGR-lipase activity was associated (P= .009) with the CPCSS, with a lower activity documented in mild-moderate CPCSS (median 391 U/L; range, 49-3747), compared to severe score (median, 558 U/L; range, 63-7133). DGGR-lipase activity was significantly, but weakly, correlated with CPSS (r= 0.233, P= .007). DGGR-lipase activity inefficiently discriminated mild-moderate vs severe CP (area under the receiver operator characteristics curve, 0.64; 95% confidence interval, 0.53-0.75; P= .012), with DLA cutoff of 428 U/L corresponding to sensitivity of 65% and specificity of 63%. Increased DLA is associated with emergency revisits in dogs with CP, possibly reflecting acute flare-ups. DGGR-lipase activity was associated with the CPCSS over the follow-ups but could not differentiate disease severity.

Cost-effectiveness of diagnostic tests during follow-up in lung cancer patients: an evidence-based study.

Many patients with non-metastatic non-small cell lung cancer (NSCLC) are cured by surgery but part of them develop recurrence. Strategies are needed to identify these relapses. Currently, there is no consensus on the follow-up schedule after curative resection for patients with NSCLC. The objective of this study is to analyze the diagnostic capacity of the tests performed during follow-up after surgery. We retrospectively reviewed 392 patients with stage I-IIIA NSCLC who underwent surgery. Data were collected from patients diagnosed between January 1st, 2010 and December 31st, 2020. Demographic and clinical data were analyzed, as well as the tests performed during their follow-up. We identified as relevant in the diagnosis of relapses those tests that prompted further investigation and change of treatment. The number of tests matches those included in clinical practice guidelines. A total of 2,049 clinical follow-up consultations were performed, of which 2,004 were scheduled (0.59% informative). A total of 1,796 blood tests were performed, of which 1,756 were scheduled (0.17% informative). A total of 1,940 chest computer tomography (CT) scans were performed, of which 1,905 were scheduled and 128 were informative (6.7%). A total of 144 positron emission tomography (PET)-CT scans were performed, 132 of which were scheduled, of which 64 (48%) were informative. In all cases, the tests performed by unscheduled request exceeded the informative result of the scheduled ones several fold. Most of the scheduled follow-up consultations were not relevant for the patients' management, and only body CT scan exceeded the threshold of 5% profitability, without reaching 10% even in stage IIIA. The profitability of the tests increased when performed in unscheduled visits. New follow-up strategies based on scientific evidence must be defined and follow-up schemes should be tailored focused on agile attention of the unscheduled demand.

Tailor board notice to the type of meeting

Depending on your organization's bylaws, your board is required to meet regularly—whether that's defined as monthly, quarterly, annually or on some other time frame. However, so‐called special meetings—basically, any meeting outside of the regularly scheduled ones—can take place any time of the year.

Effect of data gaps on the detectability and parameter estimation of massive black hole binaries with LISA

Massive black hole binaries are expected to provide the strongest gravitational wave signals for the Laser Interferometer Space Antenna (LISA), a space mission targeting $\ensuremath{\sim}\mathrm{mHz}$ frequencies. As a result of the technological challenges inherent in the mission's design, implementation, and long duration (4 yr nominal), the LISA data stream is expected to be affected by relatively long gaps where no data is collected (either because of hardware failures, or because of scheduled maintenance operations, such as repointing of the antennas toward the Earth). Depending on their mass, massive black hole binary signals may range from quasitransient to very long lived, and it is unclear how data gaps will impact detection and parameter estimation of these sources. Here, we will explore this question by using state-of-the-art astrophysical models for the population of massive black hole binaries. We will investigate the potential detectability of massive black hole binary signals by observing the effect of gaps on their signal-to-noise ratios. We will also assess the effect of the gaps on parameter estimation for these sources, using the Fisher information matrix formalism as well as full Bayesian analyses. Overall, we find that the effect of data gaps due to regular maintenance of the spacecraft is negligible, except for systems that coalesce within such a gap. The effect of unscheduled gaps, however, will probably be more significant than that of scheduled ones.

An Optimization Model for Scheduling Freight Trains on a Single Rail Track

In many countries, a rail network consists of a series of single lines with sidings where inter-train interactions (meeting, passing) occur. An effort has been made in this paper to study two of these network-related issues: 1) scheduling freight trains in a single-line corridor while ensuring the interactions to happen safely and 2) allocating freight to the scheduled trains considering the freight due/release date and train’s weight/capacity. To better illustrate the real-world freight trains’ scheduling problems, both the scheduling and allocation problems have been addressed. Minimizing the trains’ traveling time, allocating maximum freight to the scheduled ones, and minimizing the total freight tardiness at the related destination are the objective functions of this study. Both problems and their solutions have been addressed separately using integer linear programming models, but an integrated novel heuristic algorithm has been proposed to solve them. The computational results demonstrated through a generated data set show both the model validation and the efficiency of the heuristic algorithm. This heuristic algorithm has been so designed to incorporate the practical operational railway rules with modest modification and although its outputs slightly differ from the exact solutions, it can solve both models simultaneously in large scale problems.

The Role of Photovoltaics (PV) in the Present and Future Situation of Suriname

The aim of this paper is to give an overview of the energy sector and the current status of photovoltaic (PV) systems in Suriname and to investigate which role PV systems can play in this country’s future energy transition. At this moment, 64% of the power is available from diesel/heavy fuel oil (HFO) gensets while 36% is available from renewables namely hydroelectric power systems and PV systems. Suriname has renewable energy (RE) targets for 2017 and 2022 which already have been achieved by this 36%. However, the RE target of 2027 of 47% must be achieved yet. As there is abundant irradiance available, on an average 1792 kWh/m2/year and because several PV systems have already been successfully implemented, PV can play an important role in the energy transition of Suriname. In order to achieve the 2027 target with only PV systems, an additional 110 MWp of installed PV capacity will be required. Governmental and non-governmental institutes have planned PV projects. If these will be executed in the future than annually 0.8 TWh electricity will be produced by PV systems. In order to meet the electricity demand of 2027 fully, 2.2 TWh PV electricity will be required which implies that more PV systems must be implemented in Suriname besides the already scheduled ones.

The effects of liquidity trading on insider trade timing when an underlying option is present

PurposeThe purpose of this paper is to examine whether the underlying option impacts an insider’s propensity to purchase and sell before corporate announcements, the proportion of insiders’ trading after announcements relative to before announcements, and the insider’s profitability around corporate announcements.Design/methodology/approachThe authors test whether the timing information and option have impacted on the tendency of insider trade, the percentage of all shares traded by insiders in the post-announcement to pre-announcement periods and the average cumulative abnormal stock returns during the pre-announcement period.FindingsInsiders’ propensity to trade before announcements is higher for stocks without options listed than for stocks with traded options. This result is stronger for unscheduled announcements than for scheduled ones. The proportion of insiders’ trade volume after announcements relative to before announcements in stocks that have not options listed is higher than those in stocks with traded options. The positive relationship between the insiders’ signed volume and the informational content of corporate announcements is stronger in stocks without traded options than in stocks with options listed. Insider trades prior to unscheduled announcement are more profitable than those before scheduled ones.Research limitations/implicationsThe paper examines whether there is a difference between the effects of optioned stock and non-optioned stock. Roll et al. (2010) use the relative trading volume of options to stock ratio (O/S) to proxy for informed options trading activity. Future research could explore the impact of O/S. Moreover, the authors examine how insiders with private information use such information to trade in their own firms. Mehta et al. (2017) argue that insiders also use private information to facilitate trading (shadow trading) in linked firms, such as supply chain partners or competitors. Therefore, future research could consider the impact of shadow trading.Social implicationsSince the insider’s propensity to buy before announcements in stocks without options listed is larger than in stocks with traded options and the relationship is stronger for unscheduled announcements than for scheduled ones, the efforts of regulators should focus on monitoring insider trading in stocks without options listed prior to unscheduled announcements.Originality/valueFirst, Lei and Wang (2014) find that the increasing pattern of insider’s propensity to trade before unscheduled announcements is larger than that before scheduled announcements. The authors document the underlying option has impacted the insider’s propensity to purchase and sell, and the relationship is stronger for unscheduled announcements than for scheduled ones. Second, related studies show insider’s trading activity has shifted from periods before corporate announcements to periods after corporate announcements to decrease litigation risk. This paper find the underlying option has influenced the proportion of insiders’ trading after announcements relative to before announcements when the illegal insider trade-related penalties increase.

Value of Information and Use of Market Versus Limit Orders by Informed Investors

This paper examines how the value of information is related to the use of market orders by informed investors. We address this question by using a unique transaction-level data set that shows if, for a given transaction, an institutional investor used a market order or served as a liquidity provider. By combining this data with a data set on scheduled and non-scheduled company announcements, we examine how institutional investors use market versus limit orders when information value is high or low. With scheduled announcements, we find evidence that informed investors tend to use less market orders when the value of information is low, and more market orders when the value of information is high. However, we do not find statistically significant results regarding non-scheduled announcements, which can indicate that investors do not process information on non-scheduled versus scheduled announcements in the same way or that the contents of non-scheduled announcements in our sample are less important compared to scheduled ones.

Cirurgias eletivas: cancelamentos e causas

Objective: To investigate the number of cancelled elective surgeries and to identify its causes. Methods: A descriptive, exploratory, prospective and quantitative study was conducted in a university hospital using data from scheduled and cancelled elective surgeries in the period from April to June 2014, which were extracted from TASY System and the Statistical and Medial File Service. Results: 1,699 elective surgeries were scheduled during three months, of which 466 (27.4%) were cancelled. 336 (72.1%) cancellations occurred in the morning; and patients of the Brazilian Unified Health System had 384 (29.2%) surgeries cancelled of the 1,314 scheduled ones. The Proctology sector had 22 cancelled surgeries (43.1%) of 51 scheduled, and Orthopedics had 133 (38.3%) of 347. The main reason for cancellation was “surgeon’s criterion”, seen in 264 cases (56.7%). Conclusion: The number of cancellations was high, and the detailed causes were not identified because the records do not specifically report the reason for cancellation.

A Novelty for the Definition of Virtuous Economic Framework of the Italian Motorway Traffic Management: MPCA Model

The precise and reliable assignment of parameters of the economic scenery, aimed at planning of motorway traffic, can not be separated from the analysis of the parameters of motorway safety as conflicting elements in the decision-making capacity management in conditions due to natural events or as a cause of the job scheduling road maintenance. The fundamental problem for the concessionaire of the motorways lies in the quest for the best balance between motorway safety for driver-players and the revenue from tolls paid by owners of the vehicles? In fact, in case of a crisis due to accidental events or scheduled ones as the fixed and mobile road yards, the revenue of the company is changing. This study achieves the implementation of a management model of business revenue under crisis conditions. Through repeated field surveys we have built and calibrated an economic model - IT based - that offers immediate answers for the motorways' management. So, we present a new method for the economic balance of the motorway infrastructure, in the very short term.

THE PROJECT OF ADAPTATION OF AIRPORT TO EXECUTING THE IRREGULAR SERVICE OF AIRPLANE AIRBUS 380

The aircraft Airbus A380 is the biggest aircraft in present time. Many airports need to adapt their airside infrastructure. The main duties concerns upgrading runways, and taxiways, relocating taxiways and even relocating aircraft stands and buildings to provide sufficient wings clearance. There are many hubs in the world, which must rebuild elements of infrastructures for A380. Besides these large hub and main base airports, there are other airports around the world that will experience A380 operations. The operating frequency could be either on regular basis, such as one or two scheduled arrivals a day, but also may be a much lower frequency such as for a flight diversion. Such diversions could be either due to the unavailability of the destination airport (because of weather or operational issues) or because of an in-flight emergency. It is in the interest of in-flight safety to have a reasonable number of alternate airports and runways available in addition to the scheduled ones. Aircraft operations regulations make a distinction between destination alternate aerodromes, other alternate aerodromes required to be adequate (e.g. in JAR-OPS 1) and in-flight diversion aerodromes. For those alternate airports, large-scale changes to their existing airside infrastructure would be financially excessive and never be economical. On the other hand, especially in the case of a filed alternate, a minimum should be done to properly handle the aircraft and its passengers. In paper is presented necessary requirements to service of airplane the Airbus A380. It is presented on examples of Chopin’s airport in Warsaw. Service of this type of airplane requires adaptation of parameters of runway, taxiway and ground operations.

Intertwined path formation and MAC scheduling for fast delivery of aggregated data in WSN

This paper studies the problem of data aggregation scheduling in wireless sensor networks (WSNs) to minimize time latency. In prior work on this problem, a node is assigned a parent from the set of unscheduled nodes in order to prevent the creation of cycles. However, using such a strategy reduces the time-slot reuse and consequently has a negative impact on the time latency. To address these shortcomings, we propose IPS (Interwined Path formation and MAC Scheduling), a novel cross-layer scheme for data aggregation scheduling that allows selecting a parent from all the node’s neighbors including the scheduled ones. IPS achieves reduced data delivery latency through three key design features, namely, (1) intertwining aggregation tree formation and scheduling, (2) for each node, a parent can be selected from already scheduled nodes so that the time latency is reduced and the cycles are prevented and (3) applying parent selection criteria that maximize the time slot reuse. We prove that the data delivery latency for IPS is upper-bounded by (⌊2πarccos(11+∊)⌋+3)R+Δ-4, where R is the network radius, Δ is the maximum node degree, and 0.05<∊⩽1. The simulation results show that IPS outperforms seven competing state-of-the-art aggregation scheduling algorithms in terms of latency and network lifetime.

Stock option fraud detection and an analysis for its reasons: Arabic Republic of Egypt case

This paper investigates how stock option turned from an incentive for good management to a tool of management fraud. The objective of this paper is accomplished through studying the stock option phenomenon in the Arab Republic of Egypt (ARE). Stock option grants data are obtained from all firms that have stock option grants and listed in the Egyptian stock market. The empirical study covers the period from 2006 through 2009. Detecting stock option fraud and distinguishing between control and fraud firms was done through calculating the cumulative abnormal returns before and after stock option grants. Results of this research reveal that the incidence of stock option fraud is higher in unscheduled option grants compared to scheduled ones. These results strongly support that the reason of stock option fraud in ARE is dating games rather than news announcements manipulation.

Time‐Varying Liquidity Trading, Private Information and Insider Trading

AbstractThis paper investigates the insider trading before scheduled versus unscheduled corporate announcements to explore how corporate insiders utilise their private information in response to the time‐varying liquidity trading. Using a comprehensive insider trading database, we show that: (1) the insider's propensity to trade increases in the amount of liquidity trading before both the scheduled and unscheduled announcements; (2) insiders buy (sell) more before positive (negative) announcements; and (3) insider purchases are more profitable before unscheduled announcements than before scheduled ones. They suggest that insiders time their trades around scheduled and unscheduled announcements to exploit the varying extent of liquidity trading.