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Mass spectrometry is one of the few instrumental analysis techniques that can be relatively well-understood with physics/chemistry knowledge typical of an advanced high school or a beginning undergraduate student. This positions mass spectrometry well to be used as a bridge between abstract concepts typically set as learning goals in courses at those levels, practical problem sets based on realistic data graphs, and historical or applications case studies. Such case studies tie general chemistry learning goals in with areas of student interest, potential student career paths, and/or areas with which students might already be more familiar. The purpose of this work is to provide (1) an introduction to mass spectrometry, (2) a discussion of mass spectrometry applications which are both relevant to the general chemistry curriculum and likely of interest to the student population, and (3) examples of potential mass spectrometry-based exercises that could be integrated into classroom exercises or student assessment. Importantly, all three of these purposes are addressed at a level easily accessible for either instructors with little to no mass spectrometry background or for students in the target audience. An additional goal of the proposed activities is to encourage development of student skills in graph reading and analysis. Thus, this work's aim is to serve as an instructor's reference, bridging the gap between the field of mass spectrometry and the introductory or general chemistry classroom.

Mass spectrometers are ever-increasingly powerful, user-friendly, and affordable. Thus, the addition of mass spectrometry experiments into the undergraduate laboratory curriculum is now both feasible and an effective tool to introduce students to relevant instrumentation. Here an experiment demonstrating the use of a high-resolution electrospray ionization mass spectrometer (ESI-HRMS) for the identification of peptide sequences and the differentiation of isomeric peptides was developed and implemented in a biochemistry laboratory course for third-year chemistry major undergraduate students. This lab activity was a first introduction to mass spectrometry for undergraduate biochemistry students. As a prelab assignment, students were tasked to predict the mass-to-charge ratios and the fragmentation patterns for six given peptides using an online fragmentation prediction tool (Protein Prospector's MS-Product tool). Students then analyzed two unknown peptides using ESI-HRMS. The theoretical and experimental results were compared to reveal the identity of the two unknown peptides. The student success rate of recognizing the unknown peptide sequences was 87.5%. This laboratory experiment provided students with hands-on experience using a research-grade ESI-HRMS instrument to solve a bioanalytical problem--specifically, the identification of the primary structure of a peptide of unknown sequence. Learning outcomes were evaluated for this experiment, which showed student understanding of peptide sequencing using mass spectrometry.

We develop a tractable nonparametric model for the time-varying reproductive rate of infectious diseases that combines the structure of a deterministic compartmental model and a stochastic model for incidence data. We use Bayesian inference to estimate, with uncertainty, the reproductive rate of the Coronavirus 2019 outbreak in the U.S. states of California, Florida, Michigan, New Mexico, New York, and Texas from January 2020 to March 2022. Employing the inferred reproductive rates, we estimate the posterior distribution of the time-varying reproduction numbers for each state. Compering the time-varying reproduction numbers across the states, we identify some epidemic waves, potentially driven from changes in human behavior and virus mutations. [ABSTRACT FROM AUTHOR]

The study attempts to investigate whether the use of anticonvulsant medications results in an increased risk of suicide, attempted suicide, or violent death. The results indicate that the use of such drugs does increase the risk of suicide.

The development of chronic liver diseases is mediated by sustained hepatic inflammation. Our objective was to characterize the molecular mechanisms responsible for the hepatic inflammatory response to time-limited TNF-[alpha] and IL-l[beta] expression. C57B1/6 mice were injected with 2 x [10.sup.7] plaque forming units intraperitoneally of an adenoviral vector containing TNF-[alpha] or IL-1[beta] (AdTNF-[alpha] or AdIL-1[beta]). A nonreplicating adenoviral vector served as control. Four days later, under ketamine and xylazine anesthesia, the liver microvasculature was examined by intravital microscopy. In the postsinusoidal venules, leukocyte rolling increased significantly in response to both AdTNF-[alpha] and AdIL-1[beta], compared with controls. This response was significantly reduced following injection of an anti-[[alpha].sub.4]-integrin monoclonal antibody (MAb). Postsinusoidal rolling was further reduced to baseline following injection of an anti-P-selectin or anti-L-selectin MAb. Sinusoidal adhesion was greater in mice treated with AdIL-1[beta] than with AdTNF-[alpha]. Blocking [[alpha].sub.4]-integrin, P-selectin, or L-selectin had no significant effect on sinusoidal or postsinusoidal adhesion. In separate experiments, we administered AdTNF-[alpha] or AdIL-1[beta] to mice deficient in ICAM-1. In ICAM-1-/- mice, postsinusoidal leukocyte rolling significantly increased following expression of IL-1[beta] but not TNF-[alpha]. AdIL-1[beta]- but not AdTNF-[alpha]-mediated sinusoidal adhesion was ICAM-1 dependent. AdTNF-[alpha]-induced sinusoidal adhesion was significantly reduced following 4 days of anti-MIP-2 MAb and anti-KC MAb. Prolonged expression of the cytokines TNF-[alpha] and IL-1[beta] increases hepatic leukocyte-endothelial cell interactions. Interestingly, the mechanisms through which these cytokines bring about adhesion within the sinusoids differ; AdIL-1[beta] sinusoidal adhesion uses an ICAM-1-dependent mechanism whereas AdTNF-[alpha]-mediated adhesion is ICAM-1 independent but CXC chemokine dependent. chemokine; hepatic sinusoid; intravital microscopy; adhesion molecules