A model-independent analysis of final-state interactions in \bar B_{d/s}^0 --> J/psi pi pi

Exploiting $B$-meson decays for Standard Model tests and beyond requires a precise understanding of the strong final-state interactions that can be provided model-independently by means of dispersion theory. This formalism allows one to deduce the universal pion-pion final-state interactions from the accurately known $\pi\pi$ phase shifts and, in the scalar sector, a coupled-channel treatment with the kaon-antikaon system. In this work an analysis of the decays $\bar B_d^0 \to J/\psi \pi^+\pi^-$ and $\bar B_s^0 \to J/\psi \pi^+\pi^-$ is presented. We find very good agreement with the data up to 1.05 GeV with a number of parameters reduced significantly compared to a phenomenological analysis. In addition, the phases of the amplitudes are correct by construction, a crucial feature when it comes to studies of $CP$ violation in heavy-meson decays.Comment: 25 pages, 6 figures, version published in JHE

Electrowetting at the nanoscale

Using molecular simulations of nano-sized aqueous droplets on a model graphite surface we demonstrate remarkable sensitivity of water contact angles to the applied electric field polarity and direction relative to the liquid/solid interface. The effect is explained by analyzing the influence of the field on interfacial hydrogen bonding in the nanodrop, which in turn affects the interfacial tensions. The observed anisotropy in droplet wetting is a new nanoscale phenomenon that has so far been elusive as, in current experimental setups, surface molecules represent a very low fraction of the total number affected by the field. Our findings may have important implications for the design of electrowetting techniques in fabrication and property tuning of nanomaterials

Microscopic Dynamics of the Orientation of a Hydrated Nanoparticle in an Electric Field

We use atomistic simulations to study the orientational dynamics of a nonpolar nanoparticle suspended in water and subject to an electric field. Due to molecular-level effects we describe, the torque exerted on the nanoparticle exceeds continuum-electrostatics based estimates by about a factor of two. The reorientation time of a 16.2×16.2×3.35 ̊A3 nanoparticle in a field E \u3e 0.015V/ ̊A is an order of magnitude less than the field-free orientational time (∼ 1 ns). Surprisingly, the alignment speed is nearly independent of the nanoparticle size in this regime. These findings are relevant for design of novel nanostructures and sensors and development of nanoengineering methods

Listen to the Voices: A Reflection on How 2020 and COVID-19 Have Affected Lives

Throughout the last few months of 2019, stories of a new and deadly virus were on every news channel around the world. Many Americans saw it as foreign news, others worried about the virus’ spread, and some felt that it would be contained quickly never making it past the Atlantic or Pacific. By March of 2020, COVID-19 made its way to the United States, forcing a new normal of quarantining, remote-learning/teaching, and teleworking. Graduate students and educators of Professional Opportunities Supporting Scholarly Engagement (POSSE), a College of Education program focused on research and contributing to the educational field of discourse, came together with a notion and a desire to provide support during this challenging time. Using a Google form questionnaire, POSSE reached out to as many people throughout the United States and the world to share their experiences with the changes, good and bad, over the past year

Integrative gene-metabolite network with implemented causality deciphers informational fluxes of sulphur stress response

The systematic accumulation of gene expression data, although revolutionary, is insufficient in itself for an understanding of system-level physiology. In the post-genomic era, the next cognitive step is linking genes to biological processes and assembling a mosaic of data into global models of biosystem function. A dynamic network of informational flows in Arabidopsis plants perturbed by sulphur depletion is presented here. With the use of an original protocol, the first blosystem response network was reconstructed from a time series of transcript and metabolite profiles, which, on the one hand, integrates complex metabolic and transcript data and, on the other hand, possesses a causal relationship. Using the informational fluxes within this reconstruction, it was possible to link system perturbation to response endpoints. Robustness and stress tolerance, as consequences of scale-free network topology, and hubs, as potential controllers of homeostasis maintenance, were revealed. Communication paths of propagating system excitement directed to physiological endpoints, such as anthocyanin accumulation and enforced root formation were dissected from the network. An auxin regulatory circuit involved in the control of a hypo-sulphur stress response was uncovered

Outbreak of acute hepatitis C following the use of anti-hepatitis C virus--screened intravenous immunoglobulin therapy

BACKGROUND and AIMS: Hepatitis C virus (HCV) infection has been associated with intravenous (IV) immunoglobulin (Ig), and plasma donations used to prepare IV Ig are now screened to prevent transmission. Thirty-six patients from the United Kingdom received infusions from a batch of anti-HCV antibody-screened intravenous Ig (Gammagard; Baxter Healthcare Ltd., Thetford, Norfolk, England) that was associated with reports of acute hepatitis C outbreak in Europe. The aim of this study was to document the epidemiology of this outbreak. METHODS: Forty-six patients from the United Kingdom treated with Gammagard (34 exposed and 12 unexposed to the batch) returned epidemiological questionnaires. RESULTS: Eighty-two percent of the exposed patients (28 of 34) became positive for HCV RNA. Eighteen percent of the patients (6 of 34) who had infusions with this batch tested negative for HCV RNA, but 2 of the patients had abnormal liver function and subsequently seroconverted to anti-HCV antibody positive. Twenty-seven percent of the patients (9 of 34) developed jaundice, and 79% (27 of 34) had abnormal liver transferase levels. Virus isolates (n=21), including an isolate from the implicated batch, were genotype 1a and virtually identical by sequence analysis of the NS5 region, consistent with transmission from a single source. CONCLUSIONS: Hepatitis C infection can be transmitted by anti-HCV-screened IV Ig. Careful documentation of IV Ig batch numbers and regular biochemical monitoring is recommended for all IV Ig recipients

SAMStat: monitoring biases in next generation sequencing data

Motivation: The sequence alignment/map format (SAM) is a commonly used format to store the alignments between millions of short reads and a reference genome. Often certain positions within the reads are inherently more likely to contain errors due to the protocols used to prepare the samples. Such biases can have adverse effects on both mapping rate and accuracy. To understand the relationship between potential protocol biases and poor mapping we wrote SAMstat, a simple C program plotting nucleotide overrepresentation and other statistics in mapped and unmapped reads in a concise html page. Collecting such statistics also makes it easy to highlight problems in the data processing and enables non-experts to track data quality over time

Educators\u27 Experiences With Teaching During COVID-19: Journey of a Participatory Action Research Inquiry Team

In 2015, the United Nations (UN) issued 17 Sustainable Development Goals (SDGs, 2030) for everyone in this world to address. The need to act on these goals was intensified in 2020 when the world faced the COVID-19 pandemic spotlighting inequitable infrastructures and systems throughout many countries. The UN, in SDG4, urges us to “ensure inclusive and equitable quality education and promote lifelong learning opportunities for all” (UN, 2015, p. 21). To address this crisis, the International Council on Education for Teaching (ICET) and MESHGuides sent out a call for research to scholars across the globe to capture teacher voices and find out about their experiences with teaching during COVID-19. Members of the College of Education program Professional Opportunities Supporting Scholarly Engagement (POSSE) at Texas A&M International University initiated a participatory action research project to join them and learn about changes in educators’ professional requirements. This report delineates their journey of collecting and analyzing data on teaching during COVID-19 and shares preliminary findings. Sixteen educators were interviewed in a focus group inquiry; six qualitative researchers analyzed the data using a systematic constant comparative method of analysis (Maykut & Morehouse, 1994). Educators shared challenges encountered when transferring curriculum, strategies, and pedagogical mindsets to a virtual platform. Teachers emphasized the significance of building collaborative relationships with parents as a supportive strategy. To face the pandemic-related changes, teachers paid both physical and emotional tolls, describing feelings such as frustration, helplessness, and uncertainty. As the participatory action research inquiry and analysis was being drafted as this article, at least half of the co-authors were still juggling expectations of altered face-to-face and virtual teaching–learning experiences while identifying the multiple impacts of a pandemic that lasted an entire calendar year, overlapping two academic years, while the research team had invested the time in listening to teachers’ voices to learn how best to promote equitable quality educational experiences for all