Considerations for the use of medical devices in dermatology.

This manuscript addresses the significant considerations concerning the development and use of medical devices in dermatology. With the rapidly growing demand and booming market for medical devices, especially lasers, it is crucial that dermatologists become familiar with the nuances associated with supporting clinical studies, consumer-driven marketing strategies, and the complex relationships that exist between physicians, industry, and consumers. An examination of these relationships includes an overview of the potential biases pertaining to advisory panels and treating clinicians. The aim of this paper is to serve as an introduction to the background of medical devices and to offer dermatologists important information on what should be considered before recommending treatment

Ion sequestration particles for naval anticorrosion coatings

Corrosion is the electrochemical process of a metal returning to its lower energy state, the metal oxide. The cost of corrosion is difficult to estimate. One area particularly susceptible to corrosion problems with high maintenance costs is that of the 20,000 tanks existent in the US Naval Fleet. The Navy is sponsoring the development of novel coatings and additives that can be used to decrease the rising corrosion related costs. This dissertation describes in detail the synthesis of Ion Sequestration Particles (ISP) that when added to the standard MIL-DTL-24441 or potentially another coating system act to enhance the anticorrosion properties of the coating. A solid ion sequestration core material (SISCM) is first produced. The core is then encapsulated in a second stage forming a shell that protects the SISCM sufficiently from the harmful interactions with uncured epoxy based coatings. ISPs were designed to sequester harmful ions while releasing passivating ions in their place. The passivating ions then migrate to defect sites at the coating interface where they act to inhibit corrosion. The anticorrosion performance of ISPs in epoxy coatings has been demonstrated by both 500 hrs of hot deionized water immersion and 1000 hrs of salt spray exposure (ASTM B117). The best improvements in coating performance are attained with ISP content ranging from 5-10 wt % loading in a coating. ISPs were designed to limit the transport of harmful ions through the coating. However this work has determined high diffusion coefficients for ions (CI- and PO42-) through the epoxy matrix. Without ISPs, the diffusion coefficient through the MIL-DTL-24441 coating was determined for phosphate to be 1.16x10-7 cm2/s and for chloride to be in the range of 2.7x10-9 to 5.6x10-10 cm2/s. The addition of 5 wt % ISPs to the coating had the effect of decreasing the diffusion coefficient by an average of 25.5%. These results yield the conclusion that the enhanced anticorrosion properties of coatings containing ISPs is more likely due to the passivating effect of the released phosphate ions than due to the ISPs ability to sequester harmful ions

The World of Placebos

The Placebo Effect is a fascinating but poorly understood mystery of medicine and human biology. Its workings continue to surprise scientists and patients everywhere. This is a brief introduction to the placebo effect from its early roots to current issues and new discoveries in the field

Fugitive Pull: Applying the Fugitive Disentitlement Doctrine to Foreign Defendants

Defendants force courts to decide whether to use judicial time and resources to hear a case when they either flee or refuse to submit to jurisdiction. Judges in the United States possess an exceptional discretionary power to deny access to the courts in these circumstances through the fugitive disentitlement doctrine. The fugitive disentitlement doctrine developed as federal common law and permits courts to exercise discretion in declining to hear appeals or motions from defendants classified as fugitives from justice. Historically, the fugitive disentitlement doctrine was intended to prevent courts from wasting resources adjudicating cases when a defendant has fled and remains a fugitive from justice. While traditional fugitives remain subject to the doctrine, modern courts now also apply fugitive disentitlement to foreign defendants with tenuous connections to United States jurisdiction. United States federal prosecutors can leverage the doctrine to circumvent the principle of the presumption against extraterritoriality, a legal doctrine that presumes laws do not apply outside United States borders. Consequently, as long as the government can secure an indictment, fugitive disentitlement requires that foreign defendants travel to the United States and submit to its jurisdiction. Absent an appeals process, foreign defendants must submit to United States jurisdiction and may be forced to travel great distances to defend themselves in United States courts any time a U.S. prosecutor levels charges. Allowing foreign defendants to challenge the application of the fugitive disentitlement doctrine furthers the purposes of justice and due process. This Comment argues that the United States Supreme Court should adopt the Second Circuit’s approach to fugitive disentitlement, which allows a defendant to challenge fugitivity through the collateral order doctrine as an exception to the final judgment rule

Reduced and coded sensing methods for x-ray based security

Current x-ray technologies provide security personnel with non-invasive sub-surface imaging and contraband detection in various portal screening applications such as checked and carry-on baggage as well as cargo. Computed tomography (CT) scanners generate detailed 3D imagery in checked bags; however, these scanners often require significant power, cost, and space. These tomography machines are impractical for many applications where space and power are often limited such as checkpoint areas. Reducing the amount of data acquired would help reduce the physical demands of these systems. Unfortunately this leads to the formation of artifacts in various applications, thus presenting significant challenges in reconstruction and classification. As a result, the goal is to maintain a certain level of image quality but reduce the amount of data gathered. For the security domain this would allow for faster and cheaper screening in existing systems or allow for previously infeasible screening options due to other operational constraints. While our focus is predominantly on security applications, many of the techniques can be extended to other fields such as the medical domain where a reduction of dose can allow for safer and more frequent examinations. This dissertation aims to advance data reduction algorithms for security motivated x-ray imaging in three main areas: (i) development of a sensing aware dimensionality reduction framework, (ii) creation of linear motion tomographic method of object scanning and associated reconstruction algorithms for carry-on baggage screening, and (iii) the application of coded aperture techniques to improve and extend imaging performance of nuclear resonance fluorescence in cargo screening. The sensing aware dimensionality reduction framework extends existing dimensionality reduction methods to include knowledge of an underlying sensing mechanism of a latent variable. This method provides an improved classification rate over classical methods on both a synthetic case and a popular face classification dataset. The linear tomographic method is based on non-rotational scanning of baggage moved by a conveyor belt, and can thus be simpler, smaller, and more reliable than existing rotational tomography systems at the expense of more challenging image formation problems that require special model-based methods. The reconstructions for this approach are comparable to existing tomographic systems. Finally our coded aperture extension of existing nuclear resonance fluorescence cargo scanning provides improved observation signal-to-noise ratios. We analyze, discuss, and demonstrate the strengths and challenges of using coded aperture techniques in this application and provide guidance on regimes where these methods can yield gains over conventional methods

Synthesis and Application of Functionalized Bis-Peptides Through Hindered Amide Bond Formation

This work presents significant advances towards installing chemical functionality within bis-peptide scaffolds, an important milestone towards designer, functional macromolecules for our group. First was the discovery of acyl-transfer coupling, a new synthetic route to assemble extremely hindered peptide bonds which were not previously accessible through conventional means. A novel amino-anhydride intermediate and five-membered ring acyl-transfer mechanism is postulated and multiple supporting pieces of evidence are presented. Applying this chemistry to the bis-amino acid building blocks developed in our group, the first functionalized bis-peptides were created which are oligomeric, diketopiperazine-based peptidomimetics. The first application for this new class of macromolecules was to mimic the bound conformation of the p53 ƒÑ-helical domain to its binding partner hDM2. Further structure and function optimization and characterization of the compound¡¦s biological effects showed these bis-peptides to be potent inhibitors of this protein-protein interaction, be cell-permeable and elicit a surprising biological response with human liver cancer cells

Trends in unsolicited dermatologic opinions: A national survey

In dermatology, a particularly common ethical dilemma can arise when the skin lesions of bystanders are inadvertently viewed in public settings. Dermatology is a unique field, where a person’s organ of interest is readily visible to others. When lesions are suspicious for skin disease, unsolicited medical opinions may or may not be given depending on several factors. This study examined the actions and attitudes of dermatologists with different levels of experience through the use of case scenarios with various settings and skin lesions. © 2017, Dermatology Online Journal. All rights reserved