Measurement of Three-dimensional Density Distributions by Holographic Interferometry and Computer Tomography

The use of holographic interferometry to measure two and threedimensional flows and the interpretation of multiple-view interferograms with computer tomography are discussed. Computational techniques developed for tomography are reviewed. Current research topics are outlined including the development of an automated fringe readout system, optimum reconstruction procedures for when an opaque test model is present in the field, and interferometry and tomography with strongly refracting fields and shocks

Modular digital holographic fringe data processing system

A software architecture suitable for reducing holographic fringe data into useful engineering data is developed and tested. The results, along with a detailed description of the proposed architecture for a Modular Digital Fringe Analysis System, are presented

Holographic interferometry of transparent media with reflection from imbedded test objects

In applying holographic interferometry, opaque objects blocking a portion of the optical beam used to form the interferogram give rise to incomplete data for standard computer tomography algorithms. An experimental technique for circumventing the problem of data blocked by opaque objects is presented. The missing data are completed by forming an interferogram using light backscattered from the opaque object, which is assumed to be diffuse. The problem of fringe localization is considered

Dental Hygiene and Dental Assistant Students\u27 Simulated DVI Radiographic Match Accuracy: A Pilot Study

Purpose Allied dental health care professionals have served on disaster victim identification (DVI) teams; however, the literature is void of statistical measures regarding transferable skills and disaster preparedness. The purpose of this study was to assess second year dental hygiene and dental assistant students’ match accuracy for simulated DVI radiographs and compare the match accuracy between the student groups. Methods Five patient cases were chosen at random to retrospectively collect sets of digital bitewing radiographs from two time periods. The five retrospectively selected sets of images served as simulated antemortem (AM) and postmortem (PM) radiographs. A convenience sample of second year dental hygiene and dental assistant students from two institutions (n=48) were invited to participate in this IRB-exempt descriptive observational study. The previously selected AM and PM images were randomly mismatched, and participants were asked to visually compare the image sets and indicate the matches using a drag and drop feature in an electronic survey instrument. Descriptive statistics were used to analyze the data; the significance level was set at α=0.05. Results A total of 41 dental hygiene and dental assistant students agreed to participate for a response rate of 85.4%. Eighty-five percent of the participants accurately matched five out of five sets while the remaining 15% accurately matched three out of five sets. A one-sample binomial proportion test revealed that 80% of the participants were able to match at least four out of five sets (p\u3c0.001). Dental hygiene students demonstrated increased matching performance as compared to dental assisting students (p=0.013). Conclusion Both dental hygiene and dental assistant students demonstrated transferable DVI skills to accurately match simulated AM and PM radiographs. Future research is needed in a larger sample to develop and assess best practices of DVI training to build on existing skills for allied dental health care professionals

Allied Dental Students\u27 Perceived Knowledge, Confidence, and Attitudes Regarding Disaster Victim Identification Topics

Purpose Disaster victim identification (DVI) service requires knowledge, confidence, and an attitude (KCA) of readiness. The purpose of this study was to assess allied dental students’ perceived KCA regarding DVI skills and topics. Methods A convenience sample of senior dental hygiene students (n=27) and senior dental assistant students (n=14) were recruited by email then presented mismatched simulated antemortem (AM) and postmortem (PM) bitewing radiographs and asked to indicate correct matches. Collectively, participants made 205 radiographic matches and indicated 205 degrees of certainty binarily as “positive” or “possible” (one per match). Participants also completed a researcher designed pretest/posttest electronic survey with seven 3-point Likert-scale items with answer options of “slightly”, “moderately”, or “extremely” regarding self-perceived knowledge. Statistical analyses were conducted with R software using an α=0.05 significance level. Results A total of n=41 students participated, yielding a response rate of 85.4%. A one-sided linear trend test revealed statistically significant increases of perceived confidence in knowledge from pretest to posttest regarding forensic odontologists’ role in DVI (p\u3c0.0001), DVI applications for mass fatality incidents (MFI) (p\u3c0.0001), role of dental radiology in DVI (p\u3c0.0001), and dental morphology applications for DVI (p\u3c0.0001). Participants indicated moderate or extreme confidence in personal clinical skillsets to assist forensic odontologists with DVI. A one-sided Fisher’s exact test revealed a statistically significant (p\u3c0.05) positive association between expressed degree of certainty (confidence) and correct radiographic matches. A one-sided linear trend test revealed statistically significant (p\u3c0.0001) improvements in attitude regarding participants’ perceived importance for their respective professions to volunteer in DVI. Conclusion Participants of this study reported significant improvements of self-perceived KCA regarding DVI skills and topics. These characteristics may encourage allied dental professionals to pursue further DVI educational opportunities and future service when support is needed for MFI

Monitoring outdoor tobacco policies of Virginia colleges: A descriptive analysis

Purpose: The purpose of this study was to monitor current outdoor tobacco policies of colleges within the state of Virginia. Methods: The tobacco policies of 2-year public colleges, 4-year public colleges, and 4-year private non-profit colleges in Virginia were located online. The policies were then categorized according to the types of tobacco products that were prohibited (Smoking Policies, Tobacco Policies, and E-cigarette Policies) and where those products were prohibited outdoors (No Policy, Entrance Policy, Perimeter Policy, Designated Smoking Areas Policy, All Grounds Policy). Findings: From a final sample of 62 college policies, 2 (3%) had No Policy, 29 (47%) had an Entrance Policy, 12 (19%) had a Perimeter Policy, 10 (16%) had a Designated Smoking Areas Policy, and 9 (15%) had an All Grounds Policy. Conclusions: The far majority of colleges do not meet national recommendations for outdoor tobacco policies. Practical implications and suggestions for future research are discussed in the article

Faraday waves on a viscoelastic liquid

We investigate Faraday waves on a viscoelastic liquid. Onset measurements and a nonlinear phase diagram for the selected patterns are presented. By virtue of the elasticity of the material a surface resonance synchronous to the external drive competes with the usual subharmonic Faraday instability. Close to the bicriticality the nonlinear wave interaction gives rise to a variety of novel surface states: Localised patches of hexagons, hexagonal superlattices, coexistence of hexagons and lines. Theoretical stability calculations and qualitative resonance arguments support the experimental observations.Comment: 4 pages, 4figure

Mechanisms of Hemolysis-Associated Platelet Activation

Background Intravascular hemolysis occurs after blood transfusion, in hemolytic anemias, and in other conditions, and is associated with hypercoagulable states. Hemolysis has been shown to potently activate platelets in vitro and in vivo, and several mechanisms have been suggested to account for this, including: (i) direct activation by hemoglobin (Hb); (ii) increase in reactive oxygen species (ROS); (iii) scavenging of nitric oxide (NO) by released Hb; and (iv) release of intraerythrocytic ADP. Objective To elucidate the mechanism of hemolysis-mediated platelet activation. Methods We used flow cytometry to detect PAC-1 binding to activated platelets for in vitro experiments, and a Siemens\u27 Advia 120 hematology system to assess platelet aggregation by using platelet counts from in vivo experiments in a rodent model. Results We found that Hb did not directly activate platelets. However, ADP bound to Hb could cause platelet activation. Furthermore, platelet activation caused by shearing of red blood cells (RBCs) was reduced in the presence of apyrase, which metabolizes ADP to AMP. The use of ROS scavengers did not affect platelet activation. We also found that cell-free Hb enhanced platelet activation by abrogating the inhibitory effect of NO on platelet activation. In vivo infusions of ADP and purified (ADP-free) Hb, as well as hemolysate, resulted in platelet aggregation, as shown by decreased platelet counts. Conclusion Two primary mechanisms account for RBC hemolysis-associated platelet activation: ADP release, which activates platelets; and cell-free Hb release, which enhances platelet activation by lowering NO bioavailability

The Global Emerging Infection Surveillance and Response System (GEIS), a U.S. government tool for improved global biosurveillance: a review of 2009

The Armed Forces Health Surveillance Center, Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) has the mission of performing surveillance for emerging infectious diseases that could affect the United States (U.S.) military. This mission is accomplished by orchestrating a global portfolio of surveillance projects, capacity-building efforts, outbreak investigations and training exercises. In 2009, this portfolio involved 39 funded partners, impacting 92 countries. This article discusses the current biosurveillance landscape, programmatic details of organization and implementation, and key contributions to force health protection and global public health in 2009