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The DESI Legacy Imaging Surveys (http://legacysurvey.org/) are a combination of three public projects (the Dark Energy Camera Legacy Survey, the Beijing-Arizona Sky Survey, and the Mayall z-band Legacy Survey) that will jointly image ≈14,000 deg2 of the extragalactic sky visible from the northern hemisphere in three optical bands (g, r, and z) using telescopes at the Kitt Peak National Observatory and the Cerro Tololo Inter-American Observatory. The combined survey footprint is split into two contiguous areas by the Galactic plane. The optical imaging is conducted using a unique strategy of dynamically adjusting the exposure times and pointing selection during observing that results in a survey of nearly uniform depth. In addition to calibrated images, the project is delivering a catalog, constructed by using a probabilistic inference-based approach to estimate source shapes and brightnesses. The catalog includes photometry from the grz optical bands and from four mid-infrared bands (at 3.4, 4.6, 12, and 22 μm) observed by the Wide-field Infrared Survey Explorer satellite during its full operational lifetime. The project plans two public data releases each year. All the software used to generate the catalogs is also released with the data. This paper provides an overview of the Legacy Surveys project.

The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the universe using the baryon acoustic oscillations technique. The spectra of 35 million galaxies and quasars over 14,000 square degrees will be measured during a 5-year survey. A new prime focus corrector for the Mayall telescope at Kitt Peak National Observatory will deliver light to 5,000 individually targeted fiber-fed robotic positioners. The fibers in turn feed ten broadband multi-object spectrographs. We describe the ProtoDESI experiment, that was installed and commissioned on the 4-m Mayall telescope from 2016 August 14 to September 30. ProtoDESI was an on-sky technology demonstration with the goal to reduce technical risks associated with aligning optical fibers with targets using robotic fiber positioners and maintaining the stability required to operate DESI. The ProtoDESI prime focus instrument, consisting of three fiber positioners, illuminated fiducials, and a guide camera, was installed behind the existing Mosaic corrector on the Mayall telescope. A fiber view camera was mounted in the Cassegrain cage of the telescope and provided feedback metrology for positioning the fibers. ProtoDESI also provided a platform for early integration of hardware with the DESI Instrument Control System that controls the subsystems, provides communication with the Telescope Control System, and collects instrument telemetry data. Lacking a spectrograph, ProtoDESI monitored the output of the fibers using a fiber photometry camera mounted on the prime focus instrument. ProtoDESI was successful in acquiring targets with the robotically positioned fibers and demonstrated that the DESI guiding requirements can be met.

Learning communities in health and human performance are creative approaches to traditional academic outcomes. Learning communities are becoming increasingly widespread in a variety of contexts, and there is extensive evidence suggesting that effective learning communities have important benefits for students as well as faculty. In this article, three successful learning communities in health and human performance are described, each of which linked two courses around a common theme. Following a general description of learning communities, the "Community Wellness," "Lifelong Wellness," and "Healthy Youth" communities are described in detail, and evaluative data are presented. Results of student perception surveys indicated that students were generally satisfied with the program; it promoted interaction among them; it encouraged meaningful communication between them and the instructor; it deepened their learning; and it helped them feel a sense of community. We conclude with recommendations to facilitate success and plans for future research.

Johnson C. Smith University, one of the nation's oldest historically Black colleges and universities, has a peer education program known as Students with a Realistic Mission (SWARM). SWARM's primary focus is on HIV/AIDS, other sexually transmitted disease prevention, alcohol education, and other drug awareness. During the spring 2000 semester, we integrated service learning and peer education into two health education courses titled Healthful Living and Drugs. Students enrolled in the classes serve as peer educators for the semester. We piloted the service learning component during the spring and fall 2000 semesters. The component has been evaluated and revised several times, but remains an integral part of the two courses. This article describes and reviews program development, successes and obstacles, and provides a summary of our findings. (Contains 1 figure.)

Emerging tobacco product use is increasing. We evaluated factors associated with perceived risk of and intention to use waterpipe tobacco by surveying students at a large university in the southeastern U.S. (N = 667). Proportional odds modeling assessed whether demographic characteristics and social acceptability are associated with perceived risk of waterpipe tobacco use; and if these factors and perceived risk are related to intention to use waterpipe tobacco. Participants who perceived waterpipe tobacco to be more socially acceptable had lower odds of perceiving it as risky (95% confidence interval [CI] 0.50--0.68). Compared with never users, former tobacco users and current users had lower odds of perceiving waterpipe tobacco use as risky (95% CI 0.38-0.80 and 0.28-0.63, respectively). Similarly, students with greater perceived social acceptability scores had higher odds of intending to use waterpipe tobacco (95% CI 1.41-2.63), while those who perceived greater risk had lower odds of intending to use it (95% CI 0.34-0.64). Compared with never users, former users had higher odds of intending to use waterpipe tobacco (95% CI 1.42-7.21). Among those who had ever used waterpipe tobacco, 90% reported "to socialize" as the most frequent reason for deciding to do so. Findings underscore the need for future prevention efforts.

Learning communities are becoming increasingly popular in the quest for enhancing student learning. The purpose of this study is to examine the impact of the "Healthy Youth" Learning Community on student learning outcome measures. In this study, the authors compared student learning outcome measures of students enrolled in those sections of HED 332 that were involved in the Health Youth Learning Community with those who were not. The outcome measures used were: midterm exam, final exam, lesson plan, lesson plan presentation, and overall course average. Results indicate a statistically significant difference on midterm and final exam scores. (Contains 1 table.)

Incipient fault detection in transformers can provide early warning of electrical failure and could prevent catastrophic losses. To develop transformer incipient fault detection technique, a transformer model to simulate internal incipient faults is required. This paper presents a methodology to model internal incipient winding faults in distribution transformers. These models were implemented by combining deteriorating insulation models with an internal short circuit fault model. The internal short circuit fault model was developed using finite element analysis. The deteriorating insulation model, including an aging model and an arcing model connected in parallel, was developed based on the physical behavior of aging insulation and the arcing phenomena occurring when the insulation was severely damaged. The characteristics of the incipient faults from the simulation were compared with those from some potential experimental incipient fault cases. The comparison showed the experimentally obtained characteristics of terminal behaviors of the faulted transformer were similar to the simulation results from the incipient fault models. Index Terms--Aging, arcing, distribution transformer, finite-element analysis, internal incipient winding fault, modeling.

Topic HIV/AIDS Education Grade Level and Object Areas Senior high school health education/promotion/wellness and related courses. Lesson Objectives Provide an open forum for discussing safer sex and other HIV/STD issues [...]

This paper discusses a simulation and modeling package developed at Texas A&M University, V-Elph 2.01. V-Elph facilitates in-depth studies of electric vehicle (EV) and hybrid EV (HEV) configurations or energy management strategies through visual programming by creating components as hierarchical subsystems that can be used interchangeably as embedded systems. V-Elph is composed of detailed models of four major types of components: electric motors, internal combustion engines, batteries, and support components that can be integrated to model and simulate drive trains having all electric, series hybrid, and parallel hybrid configurations. V-Elph was written in the Matlab/Simulink graphical simulation language and is portable to most computer platforms. This paper also discusses the methodology for designing vehicle drive trains using the V-Elph package. An EV, a series HEV, a parallel HEV, and a conventional internal combustion engine (ICE) driven drive train have been designed using the simulation package. Simulation results such as fuel consumption, vehicle emissions, and complexity are compared and discussed for each vehicle. Index Terms--Electric vehicle, hybrid electric vehicle, modeling, simulation.

An electrically peaking hybrid electric (ELPH) propulsion system is being developed that has a parallel configuration. A small engine is used to supply power approximately equal to the average load power. The operation of the engine is managed by a vehicle controller and an engine controller such that the engine always operates with nearly full load--the optimal fuel economy operation. An induction ac motor is used to supply the peaking power required by the peaking load (electrically peaking). The motor can also absorb the excess power of the engine while the load power is less than the peak. This power, along with the regenerative braking power, can be used to charge the batteries on board to maintain the battery state-of-charge (SOC) at a reasonable level. With the electrically peaking principle, two control strategies for the drive train have been developed. One is called MAXIMUM BATTERY SOC control strategy, by which the engine and electric motor are controlled so that the battery SOC is maintained at its top level as much as possible. This control strategy may be used in urban driving in which accelerating and decelerating driving is common and high-battery SOC is absolutely important for normal driving. The other control strategy is called ENGINE TURN-ON AND TURN-OFF control by which the engine is controlled to operate in a turn-on and turn-off manner. This control strategy may be used in highway driving. Based on the ELPH principle and the drive train control strategies, a drive train for a full-size five-seat passenger car (1700 kg of gross weight) has been designed and verified using the V-ELPH computer simulation package developed at Texas A&M University. The results show that the ELPH car can easily satisfy the performance requirement, and the fuel economy can be improved greatly over conventional vehicles. Index Terms--Design, electrically peaking, full-size passenger car, hybrid electric vehicle, simulation.

The electric power systems of U.S. Navy ships supply energy to sophisticated systems for weapons, communications, navigation and operation. Circuit breakers (CBs) and fuses are provided at different locations for isolation of faulted loads, generators or distribution system from unfaulted portions of the system. These faults could be due to widespread system fault resulting from battle damage or material casualties of individual loads or cables. After the faults and subsequent isolation of the faults, there will be unfaulted sections that are left without supply. Fast restoration of supply to these unfaulted sections of the SPS is necessary for system survivability. This paper presents a new method to reconfigure the network to restore service to unfaulted sections of the system. The problem is formulated as a variation of fixed charge network flow problem. The method is illustrated using various case studies on a small power system with similar topology to a shipboard power system. Index Terms--Network flow method, optimization, reconfiguration, restoration, shipboard power systems.

In Xenopus, XHex and cerberus are early marker genes of the anterior endomesoderm (AE), a subset of endoderm cells fated to form the liver and foregut and implicated in head induction. Using XHex and cerberus as markers we have examined the signals underlying AE induction. We show that the AE is specified by the early blastula in the absence of mesodermal signals but that cell-cell contact between presumptive AE cells is required. In overexpression experiments maternal Wnt/[Beta]-catenin and TGF-[Beta] signals (Vg1, Xnr1-2) can induce ectopic XHex and cerberus. Inhibiting these pathways with dominant interfering signalling components blocks endogenous XHex and cerberus expression. We assess the role of signals from the organiser and show that the BMP antagonists noggin and chordin are important for maintaining XHex and cerberus expression. Finally, ventral injection of XHex mRNA can induce ectopic cerberus. Our results indicate that endodermal and mesodermal patterning are closely coordinated and that the AE is likely to be specified by the combined action of dorsal Wnt/[Beta]-catenin signals and endoderm-specific factors mediated by TGF-[Beta] signalling. These results provide a starting point for understanding the molecular events underlying the progressive determination of endodermally derived organs, such as the liver and foregut. Key Words: anterior endomesoderm; Hex; cerberus; endoderm patterning; Wnt/[Beta]-catenin; TGF-[Beta]; Xenopus.