Lecture videos to supplement electromagnetic classes at Cal Poly San Luis Obispo

Electromagnetics and Transmission Lines is a fundamental, yet difficult subject in the Electrical Engineering (EE) field. To help improve information retention, a series of lecture videos was created to supplement traditional lectures, to facilitate in-class discussions, and to improve students’ proficiency and interest in electromagnetics. Engineering electromagnetics classes at California Polytechnic State University, San Luis Obispo cover fundamentals to understand and analyze cell phone communications, radar systems (air traffic control, law enforcement), and biomedical imaging (MRI). However, this subject also requires considerable mathematics preparation in vector calculus, differential equations, linear algebra, and background in both physics and EE. Lecture videos were created on the Camtasia software to produce MP4 audio-visual files. All videos include a topic outline, stationary and animated visual displays of lecture topic applications, and a detailed discussion using outlines and handwritten notes. Example calculations and real-world applications, Smith Chart graphical analysis, and Matlab computations and visual animations (standing and traveling waves, dynamic vector field and scalar contour diagrams) augment theoretical discussions and help visualize course concepts. Real-world applications including the Large Hadron Collider (CERN), RF test equipment (network analyzers), cell phone tower antennas, and radar imaging systems are introduced in the videos and related to course topics. A total of 36 videos were recorded for EE 335 (junior-level electromagnetics); average video length is 20 to 25 minutes for each 50 minute lecture. All lecture videos were stored online (dropbox.com) and made available one week prior to each class session. A student survey was conducted to assess perceived video effectiveness, to compare to traditional lectures, and to estimate video usage (how often watched, how many hours per week). Questions also include overall suggestions for video improvement, favorite (and not so favorite) parts of the class, and overall impressions. Most students appeared to value the new videos: 55% agreed with the statement “the lecture videos helped me learn course concepts.” Video length (20 – 25 minute average) was between too long (43%) and just right (29%). The most common negative comment mentioned the additional time required to view the videos over a traditional lecture class. Future efforts toward a flipped (inverted) classroom format include the development of topic videos and post-video quizzes to encourage pre-lecture viewing, as suggested in [1]. Video production improvements including minimized length and enhanced information organization will be applied to future lecture videos. Practical lab projects [2] will also be explored and added as another method of enhancing student interest in electromagnetics. Finally, information retention between traditional and flipped classroom formats will be compared to determine the relative effectiveness of both approaches

Absorber Foam Characterization for Predicting Overall Anechoic Chamber Performance

A new rectangular anechoic chamber (20’L x 10’W x 9’7”H) has been established at California Polytechnic State University (Cal Poly) through donations and financial support from industry and Cal Poly departments and programs. The chamber was designed and constructed by three graduate students as part of their thesis studies to explore and further their understanding of chamber design and antenna measurements. The chamber project has included RF absorber characterization, overall chamber performance assessment, and software development for the coordination of a positioner with a vector network analyzer. This paper presents absorber characterization as a function of incidence angle and orientation to enable an overall chamber performance analysis. Test data at low incidence angles (\u3c 30o) are compared to manufacturer performance curves at normal incidence. The mean response of the measured data indicates a correlation with manufacturer curves. Through ray tracing analysis, the ripple encountered in the test data is used to identify two effective reflection planes indicative of the foam geometry. The measured data are subsequently used to predict overall anechoic chamber performance to within 1dB for a majority of the actual scan data. Details of this analysis and comparisons to actual chamber performance are presented in a companion paper

Opposite field septum magnet system for the separation of charged particle beams

Abstract-The Japan Hadron Facility (JHF) accelerator complex comprises a 50-GeV main synchrotron, a 3-GeV rapid-cycling synchrotron, and a 400-MeV linac. The accelerators provide high-intensity, high-energy proton beams for various scientific fields. These high-intensity, high-energy accelerators, especially the 50-GeV main synchrotron, impose tight demands on the injection/extraction septum magnets for a thin structure, large aperture and high operating field. But to manufacture high field septum magnets on the condition of a large aperture is very difficult because of its extraordinarily strong electromagnetic force due to the self-field. To cope with these tight demands, new design concepts of septa are required. An opposite-field septum magnet system is one of the solutions to realize a thin septa or very high-field septum magnets

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

Spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect created in the femoral condyle using a novel double-network hydrogel

<p>Abstract</p> <p>Background</p> <p>Functional repair of articular osteochondral defects remains a major challenge not only in the field of knee surgery but also in tissue regeneration medicine. The purpose is to clarify whether the spontaneous hyaline cartilage regeneration can be induced in a large osteochondral defect created in the femoral condyle by means of implanting a novel double-network (DN) gel at the bottom of the defect.</p> <p>Methods</p> <p>Twenty-five mature rabbits were used in this study. In the bilateral knees of each animal, we created an osteochondral defect having a diameter of 2.4-mm in the medial condyle. Then, in 21 rabbits, we implanted a DN gel plug into a right knee defect so that a vacant space of 1.5-mm depth (in Group I), 2.5-mm depth (in Group II), or 3.5-mm depth (in Group III) was left. In the left knee, we did not apply any treatment to the defect to obtain the control data. All the rabbits were sacrificed at 4 weeks, and the gross and histological evaluations were performed. The remaining 4 rabbits underwent the same treatment as used in Group II, and real-time PCR analysis was performed at 4 weeks.</p> <p>Results</p> <p>The defect in Group II was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen. The Wayne's gross appearance and histology scores showed that Group II was significantly greater than Group I, III, and Control (p < 0.012). The relative expression level of type-2 collagen, aggrecan, and SOX9 mRNAs was significantly greater in Group II than in the control group (p < 0.023).</p> <p>Conclusions</p> <p>This study demonstrated that spontaneous hyaline cartilage regeneration can be induced <it>in vivo </it>in an osteochondral defect created in the femoral condyle by means of implanting the DN gel plug at the bottom of the defect so that an approximately 2-mm deep vacant space was intentionally left in the defect. This fact has prompted us to propose an innovative strategy without cell culture to repair osteochondral lesions in the femoral condyle.</p

A New Light on the Evolution and Propagation of Prehistoric Grain Pests: The World's Oldest Maize Weevils Found in Jomon Potteries, Japan

Three Sitophilus species (S. granarius L., S. oryzae L., and S. zeamais Mots.) are closely related based on DNA analysis of their endosymbionts. All are seed parasites of cereal crops and important economic pest species in stored grain. The Sitophilus species that currently exist, including these three species, are generally believed to be endemic to Asia's forested areas, suggesting that the first infestations of stored grain must have taken place near the forested mountains of southwestern Asia. Previous archaeological data and historical records suggest that the three species may have been diffused by the spread of Neolithic agriculture, but this hypothesis has only been established for granary weevils in European and southwestern Asian archaeological records. There was little archeological evidence for grain pests in East Asia before the discovery of maize weevil impressions in Jomon pottery in 2004 using the “impression replica” method. Our research on Jomon agriculture based on seed and insect impressions in pottery continued to seek additional evidence. In 2010, we discovered older weevil impressions in Jomon pottery dating to ca. 10 500 BP. These specimens are the oldest harmful insects in the world discovered at archaeological sites. Our results provide evidence of harmful insects living in the villages from the Earliest Jomon, when no cereals were cultivated. This suggests we must reconsider previous scenarios for the evolution and propagation of grain pest weevils, especially in eastern Asia. Although details of their biology or the foods they infested remain unclear, we hope future interdisciplinary collaborations among geneticists, entomologists, and archaeologists will provide the missing details