Labeling and Comparison of Isomeric Tree-Like Polyphenyl Systems

Tree-like polyphenyl systems form an important class of compounds in chemistry, in particular material science and polymers. The importance can be seen in LEDs, transmitters, and electronics. In recent years, many extremal results regarding such systems under specific constraints have been reported. More specifically are the sub-categories of such systems with extremal Wiener indices. In this article, we provide a labelling of the vertices on each hexagon (i.e., the corresponding benzene ring), which facilitates the illustration of a treelike polyphenyl system with its corresponding tree structure. This approach helps to characterize the extremal tree-like polyphenyl systems with respect to the Wiener index and compare such systems in general within isometric molecules and between molecules of different underlying tree structures. The results can be used to order these systems, which will aid in predicting the physical properties of compounds. We also briefly examined tree-like polyphenyl systems that resulted from different tree structures

Fluorescent Particles Comprising Nanoscale ZnO Layer and Exhibiting Cell-Specific Toxicity

Multifunctional smart nanostructures are disclosed that include fluorescein isothiocyanate (FITC)-encapsulated SiO2 core-shell particles with a nanoscale ZnO finishing layer, wherein an outer ZnO layer is formed on the SiO2-FITC core. These ~200 nm sized particles showed promise toward cell imaging and cellular uptake studies using the bacterium Escherichia coli and Jurkat cancer cells, respectively. The FITC encapsulated ZnO particles demonstrated excellent selectivity in preferentially killing Jurkat cancer cells with minimal toxicity to normal primary immune cells (18% and 75% viability remaining, respectively, after exposure to 60 μg/mL) and inhibited the growth of both gram-positive and gram-negative bacteria at concentrations .gtoreq.250-500 μg/mL (for Staphylococcus aureus and Escherichia coli, respectively). These results indicate that the FITC encapsulated multifunctional particles with nanoscale ZnO surface layer can be used as smart nanostructures for particle tracking, cell imaging, antibacterial treatments and cancer therapy

From Augmentation to Decomposition: A New Look at CUPED in 2023

Ten years ago, CUPED (Controlled Experiments Utilizing Pre-Experiment Data) mainstreamed the idea of variance reduction leveraging pre-experiment covariates. Since its introduction, it has been implemented, extended, and modernized by major online experimentation platforms. Many researchers and practitioners often interpret CUPED as a regression adjustment. In this article, we clarify its similarities and differences to regression adjustment and present CUPED as a more general augmentation framework which is closer to the spirit of the 2013 paper. We show that the augmentation view naturally leads to cleaner developments of variance reduction beyond simple average metrics, including ratio metrics and percentile metrics. Moreover, the augmentation view can go beyond using pre-experiment data and leverage in-experiment data, leading to significantly larger variance reduction. We further introduce metric decomposition using approximate null augmentation (ANA) as a mental model for in-experiment variance reduction. We study it under both a Bayesian framework and a frequentist optimal proxy metric framework. Metric decomposition arises naturally in conversion funnels, so this work has broad applicability

AN IP-BASED LIVE DATABASE APPROACH TO SURVEILLANCE APPLICATION DEVELOPMENT

With the proliferation of inexpensive cameras, video surveillance applications are becoming ubiquitous in many domains such as public safety and security, manufacturing, intelligent transportation systems, and healthcare. IP-based video surveillance technologies, in particular, are able to bring traditional video surveillance centers to virtually any computer at any location with an Internet connection. Today’s IP-based video surveillance systems, however, are designed for specific classes of applications. For instance, one cannot use a system designed for incident detection on highways to monitor patients in a healthcare facility. To support rapid development of video surveillance applications, we designed and implemented a new class of general purpose database management system, the live video database management system (LVDBMS). We view networked IP cameras as a special class of storage devices, and allow the user to formulate ad hoc queries expressed over live video feeds. These continuous queries are processed in real time using novel distributed computing techniques. With this environment, the users are able to develop various specific web-based video surveillance systems for a variety of applications. These systems can coexist in a unified LVDBMS framework to share the expensive deployment and operating costs of the camera networks. Our contribution is the introduction of a live database approach to video surveillance software development. In this paper, we describe our prototype and present the live video data model, the query language, and the query processing technique. 1

Experiencing the Transition to Remote Teaching and Learning during the COVID-19 Pandemic

The sudden onset of the COVID-19 pandemic severely disrupted universities around the world. In the two weeks following a shelter–in-place order, all the actors of the educational system were forced to transition to remote education. This shift required a new reliance upon technologies that these individuals might never have adopted at all, often with significant difficulties. In this paper, we present a qualitative study on a university-wide survey dataset describing student and faculty experiences of abruptly transitioning to remote teaching and learning during the spring 2020 semester at the Pennsylvania State University. We performed an inductive thematic analysis to identify the challenges and opportunities that arose during the transition. Our findings contribute to building better tools, curriculum, and supports for remote education, particularly during an unexpected crisis