Coaxial Dielectric Spectroscopy as an In-Line Process Analytical Technique for Reaction Monitoring.

The suitability of broadband dielectric spectroscopy (DS) as a tool for in-line (in situ) reaction monitoring is demonstrated. Using the esterification of 4-nitrophenol as a test-case, we show that multivariate analysis of time-resolved DS data-collected across a wide frequency range with a coaxial dip-probe-allows reaction progress to be measured with both high precision and high accuracy. In addition to the workflows for data collection and analysis, we also establish a convenient method for rapidly assessing the applicability of DS to previously untested reactions or processes.

HO + NO: Kinetics, Thermochemistry, and Evidence for a Bimolecular Product Channel.

A master equation (ME) analysis of available experimental data has been carried out on the reaction HO + NO + M ⇋ HONO + M (1a)/(-1a). The analysis, based on the ME code MESMER, uses both the association and dissociation kinetic data from the literature, and provides improved thermochemistry on reaction 1a. Our preferred model assigns two low-frequency vibrations of HONO as hindered rotors and couples these to the external rotations.

An Exploratory Investigation of Pupillometry As a Measure of Tinnitus Intrusiveness on a Test of Auditory Short-Term Memory.

Objectives: The purpose of the current study was to investigate the potential of pupillometry to provide an objective measure of competition between tinnitus and external sounds during a test of auditory short-term memory.

Design: Twelve participants with chronic tinnitus and twelve control participants without tinnitus took part in the study. Pretest sessions used an adaptive method to estimate listeners' frequency discrimination threshold on a test of delayed pitch discrimination for pure tones.

Global Master Equation Analysis of Rate Data for the Reaction CH + H ⇄ CH: ΔCH.

While forward and reverse rate constants are frequently used to determine enthalpies of reaction and formation, this process is more difficult for pressure-dependent association/dissociation reactions, especially since the forward and reverse reactions are usually studied at very different temperatures. The problems can be overcome by using a data-fitting procedure based on a master equation model. This approach has been applied to existing experimental pressure-dependent forward and reverse rate coefficients for the reaction CH + H ⇄ CH (, ) using the MESMER code to determine ΔCH from the enthalpy of the reaction.

The basis of report-difference superiority in delayed perceptual comparison tasks.

A major role for visual short-term memory (VSTM) is to mediate perceptual comparisons of visual information across successive glances and brief temporal interruptions. Research that has focused on the comparison process has noted a marked tendency for performance to be better when participants are required to report a difference between the displays rather than report the absence of a difference (i.e.

The "now moment" is believed privileged because "now" is when happening is experienced.

Hoerl & McCormack risk misleading people about the cognitive underpinnings of the belief in a privileged "now moment" because they do not explicitly acknowledge that the sense of existing in the now moment is an intrinsically temporally dynamic one. The sense of happening that is exclusive to the now moment is a better candidate for the source of belief in a privileged now.

Energy transfer in intermolecular collisions of polycyclic aromatic hydrocarbons with bath gases He and Ar.

Classical trajectory simulations of intermolecular collisions were performed for a series of polycyclic aromatic hydrocarbons interacting with the bath gases helium and argon for bath gas temperature from 300 to 2500 K. The phase-space average energy transferred per deactivating collision, ⟨∆E⟩, was obtained. The Buckingham pairwise intermolecular potentials were validated against high-level quantum chemistry calculations and used in the simulations.

Perceptual Errors Support the Notion of Masking by Object Substitution.

Two experiments examined the effect of object substitution masking (OSM) on the perceptual errors in reporting the orientation of a target. In Experiment 1, a four-dot trailing mask was compared with a simultaneous-noise mask. In Experiment 2, the four-dot and noise masks were factorially varied.

Stereoretentive Etherification of an α-Aryl-β-amino Alcohol Using a Selective Aziridinium Ring Opening for the Synthesis of AZD7594.

A selective aziridinium ring-opening was used to etherify an α-aryl-β-amino alcohol with stereochemical retention. This transformation was achieved in a biphasic system to address phenoxide solubility and the formation of a sulfonate ester impurity. The protecting group strategy was directed by a stability study of the activated α-aryl-β-amino alcohol in this system.

Change perception and change interference within and across feature dimensions.

The ability to perceive a change in a visual object is reduced when that change is presented in competition with other changes which are task-irrelevant. We performed two experiments which investigate the basis of this change interference effect. We tested whether change interference occurs as a consequence of some form of attentional capture, or whether the interference occurs at a stage prior to attentional selection of the task-relevant change.

Exploiting CELLULOSE SYNTHASE (CESA) Class Specificity to Probe Cellulose Microfibril Biosynthesis.

Cellulose microfibrils are the basic units of cellulose in plants. The structure of these microfibrils is at least partly determined by the structure of the cellulose synthase complex. In higher plants, this complex is composed of 18 to 24 catalytic subunits known as CELLULOSE SYNTHASE A (CESA) proteins.

Quantum Cascade Laser Spectral Histopathology: Breast Cancer Diagnostics Using High Throughput Chemical Imaging.

Fourier transform infrared (FT-IR) microscopy coupled with machine learning approaches has been demonstrated to be a powerful technique for identifying abnormalities in human tissue. The ability to objectively identify the prediseased state and diagnose cancer with high levels of accuracy has the potential to revolutionize current histopathological practice. Despite recent technological advances in FT-IR microscopy, sample throughput and speed of acquisition are key barriers to clinical translation.

Obtaining effective rate coefficients to describe the decomposition kinetics of the corannulene oxyradical at high temperatures.

Unimolecular reactions play an important role in combustion kinetics. An important task of reaction kinetic analysis is to obtain the phenomenological rate coefficients for unimolecular reactions based on the master equation approach. In most cases, the eigenvalues of the transition matrix describing collisional internal energy relaxation are of much larger magnitude than and well separated from the chemically significant eigenvalues, so that phenomenological rate coefficients may be unequivocally derived for incorporation in combustion mechanisms.

Object substitution masking and its relationship with visual crowding.

Object substitution masking (OSM) occurs when the perceptibility of a brief target is reduced by a trailing surround mask typically composed of four dots. Camp et al. (Journal of Experimental Psychology: Human Perception and Performance, 41, 940-957, 2015) found that crowding a target by adding adjacent flankers, in addition to OSM, had a more deleterious effect on performance than expected based on the combined individual effects of crowding and masking alone.

Evaluating the Precision of Auditory Sensory Memory as an Index of Intrusion in Tinnitus.

Objectives: The purpose of this study was to investigate the potential of measures of auditory short-term memory (ASTM) to provide a clinical measure of intrusion in tinnitus.

Design: Response functions for six normal listeners on a delayed pitch discrimination task were contrasted in three conditions designed to manipulate attention in the presence and absence of simulated tinnitus: (1) no-tinnitus, (2) ignore-tinnitus, and (3) attend-tinnitus.

Results: Delayed pitch discrimination functions were more variable in the presence of simulated tinnitus when listeners were asked to divide attention between the primary task and the amplitude of the tinnitus tone.

Infrared spectral histopathology using haematoxylin and eosin (H&E) stained glass slides: a major step forward towards clinical translation.

Infrared spectral histopathology has shown great promise as an important diagnostic tool, with the potential to complement current pathological methods. While promising, clinical translation has been hindered by the impracticalities of using infrared transmissive substrates which are both fragile and prohibitively very expensive. Recently, glass has been proposed as a potential replacement which, although largely opaque in the infrared, allows unrestricted access to the high wavenumber region (2500-3800 cm).

FTIR imaging of the molecular burden around Aβ deposits in an early-stage 3-Tg-APP-PSP1-TAU mouse model of Alzheimer's disease.

Alzheimer's disease is one of the major causes of dementia in the elderly. The disease is caused by the misfolding of water soluble alpha-helical proteins, which leads to the accumulation of β-sheets in the form of amyloid plaques, which can subsequently affect surrounding tissue areas by oxidative stress neurotoxicity. The aim of the present study was to design a novel methodology to analyze the extent to the neuronal burden around protein-rich Aβ plaques suspected to affect molecular components by oxidative stress induced by inflammatory states.

High-throughput quantum cascade laser (QCL) spectral histopathology: a practical approach towards clinical translation.

Infrared microscopy has become one of the key techniques in the biomedical research field for interrogating tissue. In partnership with multivariate analysis and machine learning techniques, it has become widely accepted as a method that can distinguish between normal and cancerous tissue with both high sensitivity and high specificity. While spectral histopathology (SHP) is highly promising for improved clinical diagnosis, several practical barriers currently exist, which need to be addressed before successful implementation in the clinic.

Thermal decomposition of graphene oxyradicals under the influence of an embedded five-membered ring.

In this study, we examined the influence of an embedded five-membered ring on the thermal decomposition of graphene oxyradicals. Their decomposition potential energy surfaces were explored at the B3LYP/6-311g(d,p) level. The temperature and pressure dependence of the rate coefficients was computed by master equation modeling.

Fundamental developments in infrared spectroscopic imaging for biomedical applications.

Infrared chemical imaging is a rapidly emerging field with new advances in instrumentation, data acquisition and data analysis. These developments have had significant impact in biomedical applications and numerous studies have now shown that this technology offers great promise for the improved diagnosis of the diseased state. Relying on purely biochemical signatures rather than contrast from exogenous dyes and stains, infrared chemical imaging has the potential to revolutionise histopathology for improved disease diagnosis.

Dimension-based attention in visual short-term memory.

We investigated how dimension-based attention influences visual short-term memory (VSTM). This was done through examining the effects of cueing a feature dimension in two perceptual comparison tasks (change detection and sameness detection). In both tasks, a memory array and a test array consisting of a number of colored shapes were presented successively, interleaved by a blank interstimulus interval (ISI).