Measurement of Thermal Stress in Railroad Rails Using Ultrasonic SH Waves

The use of welded joints in railroad tracks has led to problems of rail buckling brought about by the development of large compressive stresses during hot days. On cold days, tensile stresses can actually fracture the rail. In order to prevent this source of derailments, it is desirable to develop an easily used instrument to measure the level of stress in an arbitrary section of track in the field. Ultrasonic birefringence, acoustic emission and certain magnetic phenomena have all been used to attack this problem but they all suffer from the necessity for calibrating the sensor under stress-free conditions in order to correct for metallurgical structure variations. A new ultrasonic technique based on using surface skimming shear horizontal ultrasonic waves generated and detected by EMATs was investigated here because it rigorously eliminates the effects of metallurgical texture as well as unreliable coupling of the transducer to the part. Tests on sections of rail mounted in a 200,000 pound testing machine at the University of New Mexico demonstrated that the theory for the basic phenomenon is correct and that the stress level can be measured in spite of the presence of considerable texture in the rail microstructure

Amphotercin Washout of Fungal Peritonitis in Liver Transplant Recipient: A Novel Approach

Invasive fungal infection has a significant prevalence among organ transplant patients and is associated with high rates of morbidity and mortality. Fungal infection is difficult to identify early and subsequently difficult to effectively treat. In this case presentation we have a 45 y/o orthotopic liver transplant recipient who was profoundly sick from fungal peritonitis and due to the appearance of her abdomen and intestines, with the help of infectious disease, decided to proceed with direct amphotercin washout of the abdomen in the operating room. The patient had complete resolution of her fungal peritonitis and is doing well

Psychophysical evaluations of modulated color rendering for energy performance of LED-based architectural lighting

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.Includes bibliographical references (p. 137-146).This thesis is focused on the visual perception evaluation of colors within an environment of a highly automated lighting control strategy. Digitally controlled lighting systems equipped with light emitting diodes, LEDs, can produce a range of different qualities of light, adjustable to users' requirements. In this context of unparalleled controllability, a novel energy-saving lighting control concept inspired this research: strategic control of Red, Yellow, Green & Blue LEDs forming white light can further increase energy efficiency. The resulting (more efficient) white light, however, would have decreased "color rendering" (i.e. the ability of accurately reproduce the colors of illuminated objects). The notable point is that while color rendering is necessarily affected, the appearance and light levels of the white light can stay the same. But how objects' distorted colors are perceived within a real life architectural context is a key, ensuing question. This research investigated the hypothesis that a significant range of color distortions would be unnoticeable under a dynamically controlled LED system, when operating outside of users' main field of view. If successful, such control technique could minimize peak hours lighting energy waste, and potentially enable up to 25% of power reduction.(cont.) Three incremental series of psychophysical experiments were performed based on subjective assessment of color changes under continuously modulated color rendering from white LEDs. Visual tests were carried out for central and peripheral vision on a full scale mockup of an architectural scenario. Results confirmed the fundamental hypothesis, showing that the majority of subjects did not detect the color changes in their periphery while the same color changes were noticeable with direct observation. The conclusion chapter provides fundamental guidelines for how to extrapolate the experimental results into real life and apply the data to architectural settings. Hypothetical architectural scenarios are presented and the potential for energy savings is discussed.by Maria do Rosário Thompson.Ph.D

Who Watches the Watchmen? An Appraisal of Benchmarks for Multiple Sequence Alignment

Multiple sequence alignment (MSA) is a fundamental and ubiquitous technique in bioinformatics used to infer related residues among biological sequences. Thus alignment accuracy is crucial to a vast range of analyses, often in ways difficult to assess in those analyses. To compare the performance of different aligners and help detect systematic errors in alignments, a number of benchmarking strategies have been pursued. Here we present an overview of the main strategies--based on simulation, consistency, protein structure, and phylogeny--and discuss their different advantages and associated risks. We outline a set of desirable characteristics for effective benchmarking, and evaluate each strategy in light of them. We conclude that there is currently no universally applicable means of benchmarking MSA, and that developers and users of alignment tools should base their choice of benchmark depending on the context of application--with a keen awareness of the assumptions underlying each benchmarking strategy.Comment: Revie

Development of an Expert System for Ultrasonic Flaw Classification

The complete characterization of a flaw requires information about the flaw type (crack, void, inclusion, etc.), flaw size, and orientation. Here we are only concerned with the determination of the flaw type so that the appropriate sizing algorithms can be chosen. This type of classification problem using ultrasonic waves is very suitable for employing the tools and techniques of artificial intelligence [1,2]. Adaptive learning methods, for example, have in the past been employed to train a flaw classification module so that it can distinguish between cracks and volumetric flaws [3]. Some of the limitations of this approach, however, have been due to the empirical nature of the features used for classification and the difficulty of understanding and adjusting the decision-making process when errors occur.</p

Development of a Global Health Curriculum at Christiana Care Health System: An Independent Academic Health Center and Member of the Delaware Health Sciences Alliance

Work in Progress (16 PowerPoint slides) The Global Health Program at Christiana Care Health System (CCHS) is an innovative, multi-disciplinary educational program seeking to improve the public health knowledge base and skills of interested health professionals through didactic, simulation and clinical experiences. A recent AAMC survey revealed 30% ofU.S.medical students participated in an international elective in 2006 versus 15% in 1997. In a resident survey at CCHS in 2010, 70% of residents responded that it was important to have global health education. These figures indicate an increasing interest in global health during residency training. In order to draw interest from a variety of backgrounds, we developed a multi-disciplinary global health training program. The curriculum is designed to include CCHS staff and our colleagues at other Delaware Health Sciences Alliance (DHSA) institutions, includingNemoursA.I.DuPontHospitalfor Children,ThomasJeffersonUniversityand the University of Delaware. The core curriculum consists of a monthly lecture series, including local and guest speakers. The lectures are recorded and accessible to CCHS affiliates via intranet. In addition, we plan to incorporate a journal club, a skills workshop and develop a global health site to foster an international partnership and resident elective rotations. Since the program began in August 2011, we have had five meetings. Attendance has steadily increased in number and diversity; attendees now include undergraduates, medical students, residents, fellows, attending physicians, nurses, administrators and medical librarians. We initiated a post-meeting survey at our December meeting which demonstrated a mean increase in the level of awareness of the topic by 27%. Global health awareness allowsU.S.based health professionals to be more culturally competent and effective in advocating for the needs of the underserved in their own communities. By inviting all disciplines at multiple institutions we hope to create a community that supports and sustains global health. Learning Objectives: At the end of this session, participants will: 1. Identify the importance of a global health curriculum for training residents that are culturally aware and equipped to work in underserved populations both locally and abroad. 2. Acquire the information to initiate a global health program in a teaching hospital. 3. Learn how to incorporate a multi-disciplinary approach to global health education

Dietary nitrate modulates cerebral blood flow parameters and cognitive performance in humans: A double-blind, placebo-controlled, crossover investigation.

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Nitrate derived from vegetables is consumed as part of a normal diet and is reduced endogenously via nitrite to nitric oxide. It has been shown to improve endothelial function, reduce blood pressure and the oxygen cost of sub-maximal exercise, and increase regional perfusion in the brain. The current study assessed the effects of dietary nitrate on cognitive performance and prefrontal cortex cerebral blood-flow (CBF) parameters in healthy adults. In this randomised, double-blind, placebo-controlled, parallel-groups study, 40 healthy adults received either placebo or 450 ml beetroot juice (~5.5 mmol nitrate). Following a 90 minute drink/absorption period, participants performed a selection of cognitive tasks that activate the frontal cortex for 54 min. Near-Infrared Spectroscopy (NIRS) was used to monitor CBF and hemodynamics, as indexed by concentration changes in oxygenated and deoxygenated-haemoglobin, in the frontal cortex throughout. The bioconversion of nitrate to nitrite was confirmed in plasma by ozone-based chemi-luminescence. Dietary nitrate modulated the hemodynamic response to task performance, with an initial increase in CBF at the start of the task period, followed by consistent reductions during the least demanding of the three tasks utilised. Cognitive performance was improved on the serial 3s subtraction task. These results show that single doses of dietary nitrate can modulate the CBF response to task performance and potentially improve cognitive performance, and suggest one possible mechanism by which vegetable consumption may have beneficial effects on brain function

PROMALS3D web server for accurate multiple protein sequence and structure alignments

Multiple sequence alignments are essential in computational sequence and structural analysis, with applications in homology detection, structure modeling, function prediction and phylogenetic analysis. We report PROMALS3D web server for constructing alignments for multiple protein sequences and/or structures using information from available 3D structures, database homologs and predicted secondary structures. PROMALS3D shows higher alignment accuracy than a number of other advanced methods. Input of PROMALS3D web server can be FASTA format protein sequences, PDB format protein structures and/or user-defined alignment constraints. The output page provides alignments with several formats, including a colored alignment augmented with useful information about sequence grouping, predicted secondary structures and consensus sequences. Intermediate results of sequence and structural database searches are also available. The PROMALS3D web server is available at: http://prodata.swmed.edu/promals3d/

Vibronic Structure in Room Temperature Photoluminescence of the Halide Perovskite Cs3Bi2Br9

We report a study on the optical properties of the layered polymorph of vacancy-ordered triple perovskite Cs3Bi2Br9. The electronic structure, determined from density functional theory calculations, shows the top of the valence band and bottom of the conduction band minima are, unusually, dominated by Bi s and p states, respectively. This produces a sharp exciton peak in the absorption spectra with a binding energy that was approximated to be 940 meV, which is substantially stronger than values found in other halide perovskites and, instead, more closely reflects values seen in alkali halide crystals. This large binding energy is indicative of a strongly localized character and results in a highly structured emission at room temperature as the exciton couples to vibrations in the lattice

Fear for manufacturing? China and the future of industry in Brazil and Latin America

There has been considerable concern in Latin America over the implications of increased competition from China for local industry. These concerns include the possibility of "deindustrialization," the increased "primarization" of the region's exports and the difficulties of upgrading manufactured exports into higher technology products. This article examines the impact of Chinese competition both in the domestic market and in export markets on Brazilian industry. It documents the increased penetration of Chinese manufactures in the Brazilian market and the way in which Brazilian exports have lost market share to China in the US, European Union and four Latin American countries. Brazil, because of its more developed and locally integrated industrial sector, is not typical of other Latin American countries and the article also discusses the relevance of the Brazilian experience for the region as a whole