26 research outputs found
Device and Methods for Atomizing Fluids
One embodiment of the invention is directed to an apparatus for atomizing a fluid. This apparatus includes an atomizing nozzle assembly. The atomizing nozzle assembly includes: a spray applicator enclosure having a fluid entry zone, a flow shape profiler region, a transducer, and a cavitation enhancer module, wherein the cavitation enhancer module includes a residence modulation zone and the residence modulation zone includes a backward facing step region. The apparatus is configured such that fluid can enter the fluid entry zone to the nozzle profiler, the transducer and the cavitation enhancer module. Other embodiments relate to methods for atomizing fluids
Multimodal Intrinsic Speckle-Tracking (MIST) to extract rapidly-varying diffuse X-ray scatter
Speckle-based phase-contrast X-ray imaging (SB-PCXI) can reconstruct
high-resolution images of weakly-attenuating materials that would otherwise be
indistinguishable in conventional attenuation-based imaging. The experimental
setup of SB-PCXI requires only a sufficiently coherent source and spatially
random mask, positioned between the source and detector. The technique can
extract sample information at length scales smaller than the imaging system's
spatial resolution; this enables multimodal signal reconstruction. ``Multimodal
Intrinsic Speckle-Tracking'' (MIST) is a rapid and deterministic formalism
derived from the paraxial-optics form of the Fokker-Planck equation. MIST
simultaneously extracts attenuation, refraction, and small-angle scattering
(diffusive-dark-field) signals from a sample and is more computationally
efficient compared to alternative speckle-tracking approaches. Hitherto,
variants of MIST have assumed the diffusive-dark-field signal to be spatially
slowly varying. Although successful, these approaches have been unable to
well-describe unresolved sample microstructure whose statistical form is not
spatially slowly varying. Here, we extend the MIST formalism such that there is
no such restriction, in terms of a sample's rotationally-isotropic
diffusive-dark-field signal. We reconstruct multimodal signals of two samples,
each with distinct X-ray attenuation and scattering properties. The
reconstructed diffusive-dark-field signals have superior image quality compared
to our previous approaches which assume the diffusive-dark-field to be a slowly
varying function of transverse position. Our generalisation may assist
increased adoption of SB-PCXI in applications such as engineering and
biomedical disciplines, forestry, and palaeontology, and is anticipated to aid
the development of speckle-based diffusive-dark-field tensor tomography.Comment: 18 pages, 7 figure
Characterization of the 2016-2017 dermatology standardized letter of recommendation
© 2018 Matrix Medical Communications. All rights reserved. Objective: We aimed to analyze the reformatted standard letter of recommendation (SLOR) for dermatology residents to examine trends in grading and content based on the positions of the letter writers, their backgrounds, and their relationship with the applicant, as well as to evaluate the SLOR\u27s ability to discriminate applicants. Design: This was a retrospective characterization study of dermatology SLORs from the 2016-17 application cycle. Setting: We examined SLORs received by The Ohio State University, the University of Oklahoma, and Hofstra University Northwell Health dermatology residency programs. Participants: We included dermatology residency applicants and their letter writers from the 2016-17 application cycle. Results: A total of 141 SLORs were analyzed from 115 applicants. SLORs demonstrated grade inflation from letter writers of all backgrounds. Ratings for research potential and inquisitive nature were significantly lower than ratings for other categories. Letter writers with limited clinical and research contact graded applicants significantly lower than did writers who had more extensive contact. Word boxes were underutilized. Conclusion: The dermatology SLOR is useful in differentiating applicants, and ratings correlate with the relationships that letter writers have with their applicants. Residency programs should be aware of these findings when evaluating letters of recommendation for applicants
Use of teledermatology by dermatology hospitalists is effective in the diagnosis and management of inpatient disease.
BACKGROUND:Patient outcomes are improved when dermatologists provide inpatient consults. Inpatient access to dermatologists is limited, illustrating an opportunity to utilize teledermatology. Little is known about the ability of dermatologists to accurately diagnose and manage inpatients using teledermatology, particularly utilizing non-dermatologist generated clinical data. METHODS:This prospective study assessed the ability of teledermatology to diagnose and manage 41 dermatology consults from a large urban tertiary care center utilizing internal medicine referral documentation and photos. Twenty-seven dermatology hospitalists were surveyed. Interrater agreement was assessed by the kappa statistic. RESULTS:There was substantial agreement between in-person and teledermatology assessment of the diagnosis with differential diagnosis (median kappa = 0.83), substantial agreement in laboratory work-up decisions (median kappa = 0.67), almost perfect agreement in imaging decisions (median kappa = 1.0), and moderate agreement in biopsy decisions (median kappa = 0.43). There was almost perfect agreement in treatment (median kappa = 1.0), but no agreement in follow-up planning (median kappa = 0.0). There was no association between raw photo quality and the primary plus differential diagnosis or primary diagnosis alone. LIMITATIONS:Selection bias and single-center nature. CONCLUSIONS:Teledermatology may be effective in the inpatient setting, with concordant diagnosis, evaluation, and management decisions
Tomographic phase and attenuation extraction for a sample composed of unknown materials using X-ray propagation-based phase-contrast imaging
Propagation-based phase-contrast X-ray imaging (PB-PCXI) generates image
contrast by utilizing sample-imposed phase-shifts. This has proven useful when
imaging weakly-attenuating samples, as conventional attenuation-based imaging
does not always provide adequate contrast. We present a PB-PCXI algorithm
capable of extracting the X-ray attenuation, , and refraction, ,
components of the complex refractive index of distinct materials within an
unknown sample. The method involves curve-fitting an error-function-based model
to a phase-retrieved interface in a PB-PCXI tomographic reconstruction, which
is obtained when Paganin-type phase-retrieval is applied with incorrect values
of and . The fit parameters can then be used to calculate true
and values for composite materials. This approach requires no
a priori sample information, making it broadly applicable. Our PB-PCXI
reconstruction is single distance, requiring only one exposure per tomographic
angle, which is important for radiosensitive samples. We apply this approach to
a breast-tissue sample, recovering the refraction component, , with 0.6
- 2.4\% accuracy compared to theoretical values.Comment: 8 pages, 4 figures and 1 tabl
The Limitation of Applying Heat to the External Lid Surface: A Case of Recalcitrant Meibomian Gland Dysfunction
The effects on the inner surface temperatures of the upper and lower eyelids of four commercial heat therapies were compared for an individual with recalcitrant meibomian gland dysfunction. Three therapies (Bruder mask, Blephasteam, and MiBoFlo) involved the application of heat to the external lid surface, and the fourth (LipiFlow) applied heat to the internal lid surface. Only LipiFlow was effective in elevating the inner surface temperatures to the reported 40°C therapeutic threshold for melting obstructed meibum
Cutaneous immune-related adverse events to checkpoint inhibitors
© 2020 Elsevier Inc. The development of immunotherapy has led to a paradigm shift in the treatment of both solid and hematologic malignancies. As immunomodulatory therapies are employed with increasing frequency, a greater number of immune-related adverse reactions are being reported, and the majority of these involve the skin. As a result, dermatologists are increasingly becoming involved in the management of these cutaneous adverse reactions—often providing critical recommendations regarding ongoing cancer treatment. Cutaneous immune-related adverse reactions can vary significantly from patient to patient, making early recognition and timely intervention imperative to mitigate associated morbidity and potential treatment interruption. Although there is considerable overlap in the cutaneous adverse events caused by these immune checkpoint inhibitors, specific eruptions are characteristically associated with particular checkpoint inhibitors. In addition, a patient\u27s comorbidities or immune status can play a significant role in the presentation and management of such adverse reactions. This review characterizes and provides management guidelines for the various cutaneous toxicities associated with checkpoint inhibitor therapy, including CTLA-4 inhibitors, PD-1 inhibitors, and PD-L1 inhibitors. © 2020 Elsevier Inc. All rights reserved
Ixazomib-induced cutaneous necrotizing vasculitis
© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. Ixazomib is a second-generation proteasome inhibitor that has been approved in the combination treatment of multiple myeloma and is currently under clinical investigation for the management of Waldenstrom’s macroglobulinemia. While cutaneous adverse events secondary to proteasome inhibitors have been reported, the side effect profile of ixazomib remains to be documented. We report two patients, one with multiple myeloma and one with Waldenstrom’s macroglobulinemia, who developed cutaneous necrotizing vasculitis after the initiation of ixazomib. Both patients exhibited no signs of systemic vasculitis and completed their anti-cancer regimens with resolution of their respective eruptions following dose reductions in ixazomib and initiation of low-dose prednisone. A collaborative effort towards the characterization of such cutaneous toxicities facilitates early intervention, maintenance of life-preserving anti-cancer therapy, and allows clinicians opportunity to better understand the pathophysiology of vasculitis. Moreover, appropriate identification and characterization of cutaneous toxicities from novel therapies allows providers to accurately identify safety concerns, treat toxicity, and improve patient quality of life
Speckle-Based X-Ray Dark-Field Tomography of an Attenuating Object
Spatial resolution in standard phase-contrast X-ray imaging is limited by the finite number and size of detector pixels. This limits the size of features that can be seen directly in projection images or tomographic reconstructions. Dark-field imaging allows information regarding such features to be obtained, as the reconstructed image is a measure of the position-dependent small-angle X-ray scattering of incident rays from the unresolved microstructure. In this paper we utilize an intrinsic speckle-tracking-based X-ray imaging technique to obtain the effective dark-field signal from a wood sample. This effective dark-field signal is extracted using a Fokker-Planck type formalism, which models the deformations of illuminating reference-beam speckles due to both coherent and diffusive scatter from the sample. We here assume that (a) small-angle scattering fans at the exit surface of the sample are rotationally symmetric, and (b) the object has both attenuating and refractive properties. The associated inverse problem, of extracting the effective dark-field signal, is numerically stabilised using a "weighted determinants"approach. Effective dark-field projection images are presented, as well as the dark-field tomographic reconstructions obtained using Fokker-Planck implicit speckle-tracking