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Intra-arterial chemotherapy (IAC) represents a mainstay in the treatment of retinoblastoma. In a minority of cases, the external carotid artery (ECA) serves as the dominant supply to the central retinal artery and is associated with prolonged fluoroscopy times and higher intraprocedural radiation doses. The aim of this study was to evaluate the utility of time-of-flight (TOF) magnetic resonance angiography (MRA) for prospective determination of internal (ICA) versus ECA dominance for procedural planning. Between April 2017 and December 2020 (44 months), staging MR prior to IAC for retinoblastoma included variant spatial saturation band position TOF angiography. Exams were then retrospectively reviewed for concordance of ICA versus ECA dominance between the two modalities. Eight consecutive patients were included in the study. Mean patient age at time of diagnosis was 20.3 ± 10.7 months (range: 2.7–33.2 months). Ten affected eyes were included (2 cases of bilateral disease), with stage D disease in eight eyes and stage B disease in two eyes. MRA techniques demonstrated antegrade ophthalmic artery (OA) flow in 9/10 (90%) of affected eyes. Subsequent catheter angiography confirmed ICA dominant supply in 9/9 (100%). For a single affected eye (10%), the OA was demonstrated as orthotopic by T2 flow void, nonvisualized on anterior saturation TOF sequences, and faintly visualized on posterior saturation TOF sequences. Aggregate MRA to catheter angiographic concordance was 10/10 (100%). Variant saturation TOF MRA predicts ICA versus ECA dominant supply to the central retinal artery in retinoblastoma. [ABSTRACT FROM AUTHOR]

A reanalysis of data from a national telephone poll (n1181) conducted in 1991 determined that if local libraries faced a fiscal crisis, 47% favored raising taxes, 44% preferred instituting user fees, and 9% advocated reducing services. Frequent library use, urban residence, higher level of education, and greater income were associated with a preference for taxes. (PEN)

Despite the well-known benefits that autonomous technologies bring to supply chain and logistics, the adoption of such technologies remains a challenging task. This study seeks to investigate how firms that are associated with the generation of freight movements in Niagara Region (Canada) will respond to new autonomous technologies. Structural Equation Modeling was used to extract meaningful features from the dataset obtained from an extensive and in-depth survey. The survey was designed to help better understand firms' views regarding autonomous technologies. The results showed that firms with a higher percentage of e-commerce sales are more likely to adopt autonomous technologies. Results also showed that third-party logistics providers are likely to play an important role in facilitating a path to adoption. The number of product lines, the number of transportation assets, and the number of import countries are other important contributing factors that can affect firms' levels of interest in autonomous technologies. [ABSTRACT FROM AUTHOR]

Governments in many jurisdictions are taking measures to promote the use of electric vehicles. As part of this goal, it is crucial to provide a sufficient number of charging stations to alleviate drivers' anxieties associated with the range of the vehicle. The goal of this research is to help governments develop vehicle charging networks for public use via the application of multistage stochastic integer programming model that determines both the locations and capacities of charging facilities over finite planning horizons. The logit choice model is used to estimate drivers' choices of nearby charging stations. Moreover, we characterize the charging demand as a function of the charging station quantity to reflect the range anxiety of consumers. The objective of the model is to minimize the expected total cost of installing and operating the charging facilities. An approximation algorithm, a heuristic algorithm, and a branch‐and‐price algorithm are designed to solve the model. We conduct numerical experiments to test the efficiency of these algorithms. Importantly, each algorithm has advantages over the CPLEX MIP solver. Finally, the City of Oakville in Ontario, Canada, is used to demonstrate the effectiveness of this model. [ABSTRACT FROM AUTHOR]

A choice model is designed to determine the correct utility optimization of the aggregates based on the nested logit model. In contrast to the multinomial logit model, the new model permits the correlation of independent error terms, which are related with elemental derivatives that are localized within a single aggregate. This is done following the asymptotic theory of extremes which allows the substitution of the error terms distributed by Gumbel, in the presence of large numbers of derivatives in the aggregate zones.

Acute appendicitis is a common cause of abdominal surgery in children, and is the result of appendiceal luminal obstruction and subsequent inflammation. The clinical presentation is often variable, allowing imaging to play a central role in disease identification and characterization. Ultrasound is often the modality of choice for diagnosis of appendicitis in children. Ready availability and lack of ionizing radiation are attractive features of sonography, though operator dependence is a potential barrier. Computed tomography (CT) was historically the preferred modality in children, as in adults, but recent awareness of the risks of radiation has reduced its usage. The purpose of this article is to detail the imaging findings of appendicitis in children. The discussion will focus on typical signs of appendicitis seen on ultrasound, CT, and magnetic resonance imaging. Considerations for percutaneous drainage by interventional radiology will also be presented. Finally, the evolution of imaging algorithms for appendicitis will be discussed. [ABSTRACT FROM AUTHOR]