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By early January 2023, the COVID-19 pandemic had caused >6.7 million deaths worldwide (1), and severe socioeconomic hardship (2-4), particularly for racial minorities (5,6). Children experienced pandemic-related school closures that [...]

Inspired by its success for their continuous counterparts, the standard approach to deal with mixed-integer recourse (MIR) models under distributional uncertainty is to use distribu- tionally robust optimization (DRO). We argue, however, that this modeling choice is not always justified since DRO techniques are generally computationally challenging when integer decision variables are involved. That is why we propose an alternative approach for dealing with distributional uncertainty for the special case of simple integer recourse (SIR) models, which is aimed at obtaining models with improved computational tractability. We show that such models can be obtained by pragmatically selecting the uncertainty set. Here, we consider uncertainty sets based on the Wasserstein distance and also on generalized moment conditions. We compare our approach with standard DRO both numerically and theoretically. An important side result of our analysis is the derivation of performance guarantees for convex approximations of SIR models. In contrast to the literature, these error bounds are not only valid for a continuous distribution but hold for any distribution. [ABSTRACT FROM AUTHOR]

Manduca sexta, known as the tobacco hornworm or Carolina sphinx moth, is a lepidopteran insect that is used extensively as a model system for research in insect biochemistry, physiology, neurobiology, development, and immunity. One important benefit of this species as an experimental model is its extremely large size, reaching more than 10 g in the larval stage. M. sexta larvae feed on solanaceous plants and thus must tolerate a substantial challenge from plant allelochemicals, including nicotine. We report the sequence and annotation of the M. sexta genome, and a survey of gene expression in various tissues and developmental stages. The Msex_1.0 genome assembly resulted in a total genome size of 419.4 Mbp. Repetitive sequences accounted for 25.8% of the assembled genome. The official gene set is comprised of 15,451 protein-coding genes, of which 2498 were manually curated. Extensive RNA-seq data from many tissues and developmental stages were used to improve gene models and for insights into gene expression patterns. Genome wide synteny analysis indicated a high level of macrosynteny in the Lepidoptera. Annotation and analyses were carried out for gene families involved in a wide spectrum of biological processes, including apoptosis, vacuole sorting, growth and development, structures of exoskeleton, egg shells, and muscle, vision, chemosensation, ion channels, signal transduction, neuropeptide signaling, neurotransmitter synthesis and transport, nicotine tolerance, lipid metabolism, and immunity. This genome sequence, annotation, and analysis provide an important new resource from a well-studied model insect species and will facilitate further biochemical and mechanistic experimental studies of many biological systems in insects.

The flipped classroom (FC) model has emerged as an innovative solution to improve student-centered learning. However, studies measuring student performance of material in the FC relative to the lecture classroom (LC) have shown mixed results. An aim of this study was to determine if the disparity in results of prior research is due to level of cognition (low or high) needed to perform well on the outcome, or course assessment. This study tested the hypothesis that (1) students in a FC would perform better than students in a LC on an assessment requiring higher cognition and (2) there would be no difference in performance for an assessment requiring lower cognition. To test this hypothesis the performance of 28 multiple choice anatomy items that were part of a final examination were compared between two classes of first year medical students at the University of Utah School of Medicine. Items were categorized as requiring knowledge (low cognition), application, or analysis (high cognition). Thirty hours of anatomy content was delivered in LC format to 101 students in 2013 and in FC format to 104 students in 2014. Mann Whitney tests indicated FC students performed better than LC students on analysis items, U = 4243.00, P = 0.030, r = 0.19, but there were no differences in performance between FC and LC students for knowledge, U = 5002.00, P = 0.720 or application, U = 4990.00, P = 0.700, items. The FC may benefit retention when students are expected to analyze material.

Midazolam, a potent anxiolytic drug with sedative properties, is susceptible to degradation by both light and hydrolysis in aqueous solution. When formulated as an intranasal product it was found to be effective in achieving seizure control in epileptic patients. In order to deliver an adequate therapeutic dose to a patient, a nasal formulation requires the concentration of midazolam to be higher than its’ aqueous solubility. One way to increase midazolam solubility to a therapeutic concentration, is complexation with randomly methylated-β-cyclodextrin. Thus, it is important to determine how complexation with cyclodextrin affects the rate of degradation and type of midazolam degradants that are formed. We have found that complexation with cyclodextrin decreases its photostability. More importantly, the degradation profile for midazolam is significantly altered when it is complexed with randomly methylated-β-cyclodextrin, what we partly confirmed in our previous work.1 By continuing our study we have found that degradation products, not observed on the photodegradation of uncomplexed midazolam are observed in significant quantities when it is complexed with randomly methylated-β-cyclodextrin. The decreased photostability was accompanied by the appearance of two new degradation products, an intermediate structure and a dimer. Photoproduct formation followed the same pattern as in the forced degradation studies, further confirming the presence of an intermediate. The production of these new photodegradants, characterized with their MS spectra, as well as proposed degradation mechanism of midazolam is discussed.

Diligent preparation and effective countermeasures are critical to mitigating future influenza pandemics. The 1918 influenza pandemic, the most severe in recent history, resulted in [approximately equal to] 50 million deaths [...]

Abstract. We consider two types of convex approximations of two-stage totally unimodular integer recourse models. Although worst-case error bounds are available for these approximations, their actual performance has not yet [...]

Oil and gas companies are drilling and developing fields in the Arctic Ocean, which is an environment with ice floes. These companies must protect their platforms from ice floe collisions. [...]

The infrastructure of the United States, and the world, is increasingly interconnected. The ongoing integration of systems--including transportation, energy, water, communications, finance and more--has been central to their growth in [...]

Influenza pandemics occur when novel strains of the influenza virus emerge in human populations and spread worldwide (1). There were 3 influenza pandemics in the 20th century (1918, 1957, and [...]