Early detection of bacterial pneumonia by characteristic induced odor signatures.

Introduction: The ability to detect pathogenic bacteria before the onsets of severe respiratory symptoms and to differentiate bacterial infection allows to improve patient-tailored treatment leading to a significant reduction in illness severity, comorbidity as well as antibiotic resistance. As such, this study refines the application of the non-invasive Secondary Electrospray Ionization-High Resolution Mass Spectrometry (SESI-HRMS) methodology for real-time and early detection of human respiratory bacterial pathogens in the respiratory tract of a mouse infection model.

Methods: A real-time analysis of changes in volatile metabolites excreted by mice undergoing a lung infection by Staphylococcus aureus or Streptococcus pneumoniae were evaluated using a SESI-HRMS instrument.

Preservation of exhaled breath samples for analysis by off-line SESI-HRMS: proof-of-concept study.

Secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS) is an established technique in the field of breath analysis characterized by its short analysis time, as well as high levels of sensitivity and selectivity. Traditionally, SESI-HRMS has been used for real-time breath analysis, which requires subjects to be at the location of the analytical platform. Therefore, it limits the possibilities for an introduction of this methodology in day-to-day clinical practice.

Mouse tracking performance: A new approach to analyzing continuous mouse tracking data.

Mouse tracking is an important source of data in cognitive science. Most contemporary mouse tracking studies use binary-choice tasks and analyze the curvature or velocity of an individual mouse movement during an experimental trial as participants select from one of the two options. However, there are many types of mouse tracking data available beyond what is produced in a binary-choice task, including naturalistic data from web users.

Real-Time Volatile Metabolomics Analysis of Dendritic Cells.

Dendritic cells (DCs) actively sample and present antigen to cells of the adaptive immune system and are thus vital for successful immune control and memory formation. Immune cell metabolism and function are tightly interlinked, and a better understanding of this interaction offers potential to develop immunomodulatory strategies. However, current approaches for assessing the immune cell metabolome are often limited by end-point measurements, may involve laborious sample preparation, and may lack unbiased, temporal resolution of the metabolome.

Hashtags as signals of political identity: #BlackLivesMatter and #AllLivesMatter.

We investigate perceptions of tweets marked with the #BlackLivesMatter and #AllLivesMatter hashtags, as well as how the presence or absence of those hashtags changed the meaning and subsequent interpretation of tweets in U.S. participants.

Radiance backscattered by a strongly scattering medium in the high spatial frequency limit.

We study the radiative transfer of a spatially modulated plane wave incident on a half-space composed of a uniformly scattering and absorbing medium. For spatial frequencies that are large compared to the scattering coefficient, we find that first-order scattering governs the leading behavior of the radiance backscattered by the medium. The first-order scattering approximation reveals a specific curve on the backscattered hemisphere where the radiance is concentrated.

Rapid detection of and by real-time analysis of volatile metabolites.

Early detection of pathogenic bacteria is needed for rapid diagnostics allowing adequate and timely treatment of infections. In this study, we show that secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS) can be used as a diagnostic tool for rapid detection of bacterial infections as a supportive system for current state-of-the-art diagnostics. Volatile organic compounds (VOCs) produced by growing .

Medical Workflow Design and Planning Using Node-RED Data Fusion.

The space of clinical planning requires a complex arrangement of information, often not capable of being captured in a singular dataset. As a result, data fusion techniques can be used to combine multiple data sources as a method of enriching data to mimic and compliment the nature of clinical planning. These techniques are capable of aiding healthcare providers to produce higher quality clinical plans and better progression monitoring techniques.

Modeling broadband cloaking using 3D nano-assembled plasmonic meta-structures.

The concept of "cloaking" an object is a very attractive one, especially in the visible (VIS) and near infra-red (NIR) regions of the electromagnetic spectrum, as that would reduce the visibility of an object to the eye. One possible route to achieving this goal is by leveraging the plasmonic property of metallic nanoparticles (NPs). We model and simulate light in the VIS and NIR scattered by a core of a homogeneous medium, covered by plasmonic cloak that is a spherical shell composed of gold nanoparticles (AuNPs).

Intensity-only inverse scattering with MUSIC.

We present a method for inverse scattering that relies on intensity-only measurements of the scattered field on a single measurement plane. By collecting measurements from a suite of experiments in which the sample is illuminated using different incident fields, we create sufficient data diversity to overcome the limitations of the intensity-only measurements. We give an explicit procedure that uses an algebraic relation called the polarization identity to convert intensity measurements of scattered fields to interferometric measurements in which one of the scattered fields serves as the reference.

Multimodal Analgesia for Perioperative Management of Patients presenting for Spinal Surgery.

Multimodal, non-opioid based analgesia has become the cornerstone of ERAS protocols for effective analgesia after spinal surgery. Opioid side effects, dependence and legislation restricting long term opioid use has led to a resurgence in interest in opioid sparing techniques. The increasing array of multimodal opioid sparing analgesics available for spinal surgery targeting novel receptors, transmitters, and altering epigenetics can help provide an optimal perioperative experience with less opioid side effects and long-term dependence.

Quantitative subsurface imaging in strongly scattering media.

We present a method to obtain quantitatively accurate images of small obstacles or inhomogeneities situated near the surface of a strongly scattering medium. The method uses time-resolved measurements of backscattered light to form the images. Using the asymptotic solution of the radiative transfer equation for this problem, we determine that the key information content in measurements is modeled by a diffusion approximation that is valid for small source-detector distances, and shallow penetration depths.

Suitability evaluation of new endogenous biomarkers for the identification of nitrite-based urine adulteration in mass spectrometry methods.

Urine adulteration to circumvent positive drug testing is a fundamental challenge for toxicological laboratories all over the world. Untargeted mass spectrometry (MS) methods used in metabolomics had previously revealed uric acid (UA), histidine, methylhistidine, and their oxidation products, for example 5-hydroxyisourate (HIU) as potential biomarkers for urine adulteration using potassium nitrite (KNO ). These markers should be further evaluated for their reliability, stability, and routine applicability.

Asymptotic theory of circular polarization memory.

We establish a quantitative theory of circular polarization memory, which is the unexpected persistence of the incident circular polarization state in a strongly scattering medium. Using an asymptotic analysis of the three-dimensional vector radiative transfer equation (VRTE) in the limit of strong scattering, we find that circular polarization memory must occur in a boundary layer near the portion of the boundary on which polarized light is incident. The boundary layer solution satisfies a one-dimensional conservative scattering VRTE.

A new metabolomics-based strategy for identification of endogenous markers of urine adulteration attempts exemplified for potassium nitrite.

Urine adulteration to circumvent positive drug testing represents a problem for toxicological laboratories. While creatinine is a suitable marker for dilution, detection of chemicals is often performed by dipstick tests associated with high rates of false positives. Several methods would be necessary to check for all possible adulterants.

Generalized Kubelka-Munk approximation for multiple scattering of polarized light.

We introduce a new model for multiple scattering of polarized light by statistically isotropic and mirror-symmetric particles, which we call the generalized Kubelka-Munk (gKM) approximation. It is obtained through a linear transformation of the system of equations resulting from applying the double spherical harmonics approximation of order one to the vector radiative transfer equation (vRTE). The result is a 32×32 system of differential equations that is much simpler than the vRTE.

Extending generalized Kubelka-Munk to three-dimensional radiative transfer.

The generalized Kubelka-Munk (gKM) approximation is a linear transformation of the double spherical harmonics of order one (DP) approximation of the radiative transfer equation. Here, we extend the gKM approximation to study problems in three-dimensional radiative transfer. In particular, we derive the gKM approximation for the problem of collimated beam propagation and scattering in a plane-parallel slab composed of a uniform absorbing and scattering medium.

Diffuse optical tomography using the one-way radiative transfer equation.

We present a computational study of diffuse optical tomography using the one-way radiative transfer equation. The one-way radiative transfer is a simplification of the radiative transfer equation to approximate the transmission of light through tissues. The major simplification of this approximation is that the intensity satisfies an initial value problem rather than a boundary value problem.

Forward-peaked scattering of polarized light: erratum.

We intend to correct the typographical errors that occurred in our recent Letter [Opt. Lett.39, 6422 (2014)].

Forward-peaked scattering of polarized light.

Polarized light propagation in a multiple scattering medium is governed by the vector radiative transfer equation. We analyze the vector radiative transfer equation in asymptotic limit of forward-peaked scattering and derive an approximate system of equations for the Stokes parameters, which we call the vector Fokker-Planck approximation. The vector Fokker-Planck approximation provides valuable insight into several outstanding issues regarding the forward-peaked scattering of polarized light such as the polarization memory phenomenon.

"Good is up" is not always better: a memory advantage for words in metaphor-incompatible locations.

Four experiments examined whether memory for positive and negative words depended on word location and vertical hand movements. Cognitive processing is known to be facilitated when valenced stimuli are presented in locations that are congruent with the GOOD is UP conceptual metaphor, relative to when they are presented in incongruent locations. In both free recall and recognition tasks, we find a memory advantage for words that had been studied in metaphor incongruent locations (positive down, negative up).

Deriving Kubelka-Munk theory from radiative transport.

We derive Kubelka-Munk (KM) theory systematically from the radiative transport equation (RTE) by analyzing the system of equations resulting from applying the double spherical harmonics method of order one and transforming that system into one governing the positive- and negative-going fluxes. Through this derivation, we establish the theoretical basis of KM theory, identify all parameters, and determine its range of validity. Moreover, we are able to generalize KM theory to take into account general boundary sources and nonhomogeneous terms, for example.

Tunable delivery of siRNA from a biodegradable scaffold to promote angiogenesis in vivo.

Therapeutic application of this approach to silence prolyl hydroxylase domain 2 promoted expression of pro-angiogenic genes controlled by HIF1α and enhanced scaffold vascularization . This technology provides a new standard for efficient and controllable gene silencing to modulate host response within regenerative biomaterials.

Radiative transport produced by oblique illumination of turbid media with collimated beams.

We examine the general problem of light transport initiated by oblique illumination of a turbid medium with a collimated beam. This situation has direct relevance to the analysis of cloudy atmospheres, terrestrial surfaces, soft condensed matter, and biological tissues. We introduce a solution approach to the equation of radiative transfer that governs this problem, and develop a comprehensive spherical harmonics expansion method utilizing Fourier decomposition (SHEF(N)).

Ex vivo red blood cell hemolysis assay for the evaluation of pH-responsive endosomolytic agents for cytosolic delivery of biomacromolecular drugs.

Phospholipid bilayers that constitute endo-lysosomal vesicles can pose a barrier to delivery of biologic drugs to intracellular targets. To overcome this barrier, a number of synthetic drug carriers have been engineered to actively disrupt the endosomal membrane and deliver cargo into the cytoplasm. Here, we describe the hemolysis assay, which can be used as rapid, high-throughput screen for the cytocompatibility and endosomolytic activity of intracellular drug delivery systems.