Spectral imaging in preclinical research and clinical pathology.

Spectral imaging methods are attracting increased interest from researchers and practitioners in basic science, pre-clinical and clinical arenas. A combination of better labeling reagents and better optics creates opportunities to detect and measure multiple parameters at the molecular and cellular level. These tools can provide valuable insights into the basic mechanisms of life, and yield diagnostic and prognostic information for clinical applications. There are many multispectral technologies available, each with its own advantages and limitations. This chapter will present an overview of the rationale for spectral imaging, and discuss the hardware, software and sample labeling strategies that can optimize its usefulness in clinical settings

Equilibrium and nonequilibrium effects in nucleus nucleus collisions

Abstract: Local thermal and chemical equilibration is studied for central AqA collisions at 10.7 160 AGeV in the Ultrarelativis- . tic Quantum Molecular Dynamics model UrQMD . The UrQMD model exhibits strong deviations from local equilibrium at the high density hadron string phase formed during the early stage of the collision. Equilibration of the hadron resonance matter is established in the central cell of volume Vs125 fm3 at later stages, tG10 fmrc, of the resulting quasi-isentropic expansion. The thermodynamical functions in the cell and their time evolution are presented. Deviations of the UrQMD quasi-equilibrium state from the statistical mechanics equilibrium are found. They increase with energy per baryon and lead to a strong enhancement of the pion number density as compared to statistical mechanics estimates at SPS energies. PACS: 25.75.-q; 24.10.Lx; 24.10.Pa; 64.30.q

IT Usage in Auditing and the Impact of COVID-19

The COVID-19 pandemic has drastically changed the world as we know it, and the audit field is no exception. The transition for a majority of public accounting firms and their clients to remote work amidst a global pandemic sparked my interest in the already rapidly evolving field of audit IT usage, which continually affects audit quality and efficiency. My research expands on existing studies completed on this topic prior to COVID-19 and includes three main research objectives. First, my research examines the usage and perceived importance of common types of IT audit applications, such as CAATs and data analytics, as well as productivity tools used by auditors, including video conferences and email. Furthermore, I analyze the potential impacts of COVID-19 on this usage among audit professionals of varying ages, firms, and area of work. Finally, I investigate the perceptions of the future of IT assurance departments in public accounting firms and their collaboration with financial auditors. I utilized a questionnaire to collect data from 99 auditors representing a Big 4 and large regional firm in the Midwest. My results indicate that the most used IT audit applications include Dashboards, Knowledge Management Systems, and Audit Planning/Management Software. Furthermore, all forms of technology communication tools increased in usage due to COVID-19 except for email, and auditors were equally split on whether the pandemic positively or negatively impacted work-life balance. Finally, my results indicated that nearly all auditors believe the IT assurance field will increase in size and importance in the future

Effects of Sleep Fragmentation on the Progression of Alzheimer’s Disease

Alzheimer’s Disease (AD) is a neurodegenerative disease that is characterized by amyloid-beta (Aβ) plaques, neurofibrillary tangles, neuronal death, and profound cognitive impairment. Previous studies have indicated that increased Aβ and alterations in the daily sleep-wake cycle are early risk factors and possible predictors of AD. Acute sleep deprivation decreases Aβ clearance, and increased Aβ levels stimulate neuroinflammation and accelerate loss of neurons and synapses. Likewise, it has been shown that there are higher rates of sleep disorders in AD patients. However, limited studies have investigated whether sleep fragmentation accelerates the progression of AD pathology. This partial review will discuss experiments investigating the link between sleep and AD. Additionally, we completed three pilot studies exploring whether chronic disruption of daily sleep-wake cycles with sleep fragmentation (SF) increases Aβ and neuroinflammation in the brains of transgenic mice that serve as an experimental model for AD. Mice were sorted into an undisturbed sleep (US) group and an SF group, involving stimulation for one-hour periods during the light phase, 4 times/day, 5 days/week for 4 weeks. Sleep monitoring using the noninvasive piezoelectric system showed that the US mice slept as expected during the light phase; however, SF mice had greatly reduced sleep during the SF intervals, and sleep loss was only partially restored during the dark period. Protein analysis showed that hippocampal levels of Aβ40 and Aβ42 were significantly increased in SF compared to US mice. Additionally, gene expression markers of neuroinflammation in the hippocampus were significantly elevated in SF mice. These results suggest that fragmentation of the daily sleep-wake cycle stimulates hippocampal levels of Aβ and neuroinflammation. If future rodent studies support these findings that chronic SF advances AD pathology, then improving sleep consolidation would be a potential therapeutic strategy for reducing the progression of AD in humans

Magnetotransport Properties of Quasi-Free Standing Epitaxial Graphene Bilayer on SiC: Evidence for Bernal Stacking

We investigate the magnetotransport properties of quasi-free standing epitaxial graphene bilayer on SiC, grown by atmospheric pressure graphitization in Ar, followed by H$_2$ intercalation. At the charge neutrality point the longitudinal resistance shows an insulating behavior, which follows a temperature dependence consistent with variable range hopping transport in a gapped state. In a perpendicular magnetic field, we observe quantum Hall states (QHSs) both at filling factors ($\nu$) multiple of four ($\nu=4, 8, 12$), as well as broken valley symmetry QHSs at $\nu=0$ and $\nu=6$. These results unambiguously show that the quasi-free standing graphene bilayer grown on the Si-face of SiC exhibits Bernal stacking.Comment: 12 pages, 5 figure

Unwinding of primer-templates by archaeal family-B DNA polymerases in response to template-strand uracil

Archaeal family-B DNA polymerases bind tightly to deaminated bases and stall replication on encountering uracil in template strands, four bases ahead of the primer-template junction. Should the polymerase progress further towards the uracil, for example, to position uracil only two bases in front of the junction, 3′–5′ proof-reading exonuclease activity becomes stimulated, trimming the primer and re-setting uracil to the +4 position. Uracil sensing prevents copying of the deaminated base and permanent mutation in 50% of the progeny. This publication uses both steady-state and time-resolved 2-aminopurine fluorescence to show pronounced unwinding of primer-templates with Pyrococcus furiosus (Pfu) polymerase–DNA complexes containing uracil at +2; much less strand separation is seen with uracil at +4. DNA unwinding has long been recognized as necessary for proof-reading exonuclease activity. The roles of M247 and Y261, amino acids suggested by structural studies to play a role in primer-template unwinding, have been probed. M247 appears to be unimportant, but 2-aminopurine fluorescence measurements show that Y261 plays a role in primer-template strand separation. Y261 is also required for full exonuclease activity and contributes to the fidelity of the polymerase

Compartmental Modeling of the Fluorescence Anisotropy Decay of a Cylindrically Symmetric Brownian Rotor: Identifiability Analysis

We present the results of the deterministic identifiability analysis based on similarity transformation for models of one-state excited-state events of cylindrically symmetric rotors in isotropic environments undergoing rotational diffusion described by Brownian reorientation. Such an analysis on error-free time-resolved fluorescence (anisotropy) data can reveal whether the parameters of the considered model can be determined. The fluorescence -response functions I||(t) and I(t), for fluorescence polarized respectively parallel and perpendicular to the electric vector of linearly polarized excitation, are used to construct, in convenient matrix form, expressions of the sum S(t)=I||(t)+2 I(t), the difference D(t)=I||(t)-I(t), and the time-resolved fluorescence anisotropy r(t)=D(t)/S(t). The identifiability analysis of r(t) demonstrates that the rotational diffusion coefficients D|| and D for rotation respectively about and perpendicular to the symmetry axis can be uniquely resolved. However, the polar and azimuthal angles defining the absorption and emission transition moments in the molecular reference frame are not individually identifiable. Nevertheless, the difference between the polar angles of these transition moments is uniquely determined

Design of ceramic-polymer optical composites for building energy efficiency: Infrared property control and transparent bulk thermal insulators

Of ~$1 trillion total U.S. energy use, 15$34 billion of energy waste annually. Materials design of windows, roofs and insulation is an opportunity for energy efficiency improvements, by optimizing solar absorption, transmission, infrared emission and thermal insulation. This presentation will discuss both static and dynamic/active approaches to improved energy efficiency in windows through materials design and performance improvements. Please click Additional Files below to see the full abstract