New 200 kW, 800 MHz transmitter system for lower hybrid heating

This paper describes a new rf heating system which has just been completed and is now operational on the ATC machine. The system utilizes four UHF TV klystrons to generate at least 200 kW of power at a frequency of 800 MHz. Pulse widths can be varied from 20 $mu$sec up to 20 msec. A radar type floating deck modulator along with photo-optical transmitting and receiving devices have been incorporated into the system to provide the pulse fidelity and versatility which characterizes this equipment. Modular construction was emphasized in the design, when possible, to reduce maintenance and down time in the advent of component falilure. Hybrid combining techniques are utilized in order to provide two 100 kW feeds into the machine. (auth

The Ursinus Weekly, September 24, 1917

Ursinus honors sons in army • The opening address • Enjoyable reception to new students • Fall migration of birds • Literary societies • Pep meeting • On the campus • College calendarhttps://digitalcommons.ursinus.edu/weekly/2531/thumbnail.jp

High Power Modulator/regulators for neutral beam sources

PPPL has recently completed two new Modulator/Regulators for neutral injection sources used on the ATC machine and is constructing four new ones for use with sources on the PLT machine. The ATC modulator uses the well proven 4CX35,000C tetrode as the main switch tube, while the PLT modulators will be using the new but significantly higher powered X-2170 tetrodes. Some interesting circuit and manufacturing techniques are discussed. (MOW

Radio frequency plasma heating in large tokamak systems near the lower hybrid resonance

The frequency range, power, efficiency, and pulse length of a high power rf system are discussed as they might be applied to the TFTR Tokamak facility as well as on a full scale reactor. Comparisons are made of the size, power output, and costs to obtain microwave power sufficient to satisfy the physics requirements. A new microwave feed concept is discussed which will improve the coupling of the microwave energy into the plasma. The unique advantages of waveguide feed systems is apparent when one considers the practical problems associated with coupling supplementary heating energy into a reactor. (auth

Fabrication of micro-structures for optically driven micromachines using two-photon photopolymerization of UV curing resins

Two-photon photopolymerization of UV curing resins is an attractive method for the fabrication of microscopic transparent objects with size in the tens of micrometers range. We have been using this method to produce three-dimensional structures for optical micromanipulation, in an optical system based on a femtosecond laser. By carefully adjusting the laser power and the exposure time we were able to create micro-objects with well-defined 3D features and with resolution below the diffraction limit of light. We discuss the performance and capabilities of a microfabrication system, with some examples of its products.Comment: 12 pages, 10 figure

The Ursinus Weekly, April 16, 1917

Varsity nine loses close game • Military training officially instituted • Hamilton Holt on Japan to-day • Zwinglian prize essay: The indifference of youth • First aid class • Seminary notes • Christian organizations • Literary societies • On the campus • Our spring birdshttps://digitalcommons.ursinus.edu/weekly/2589/thumbnail.jp

Effects of Partnerships between Adolescents with Developmental Disabilities and Service Dogs

Background: With increasing frequency, service dogs are being placed with children with developmental disabilities (DDs). Occupational therapists and other professionals have advocated for the therapeutic use of service dog partnerships to facilitate greater independence and quality of life. There are no studies that examine service dog intervention with adolescents. Method: This study focused on the effects of partnerships between service dogs and three participant dyads, each including an adolescent with DDs and a parent. A single-subject, alternating treatment design was used to compare the effects of two conditions (service dog present or not present). The effects were examined for adolescents’ anxiety behaviors during transitions and during grocery store shopping, for social interactions during grocery store shopping, and for parents’ reported levels of stress. Results: Findings were that service dog partnerships reduced the presence of anxiety behaviors during transitions for one of the three adolescents; reduced the presence of anxiety behaviors during grocery store visits for two of the three adolescents; increased social interactions for all three of the participant dyads; and had no meaningful impact on self-reported parental stress level. Conclusion: For adolescents with DDs, professionals may want to consider service dog partnerships to decrease anxiety behaviors and increase social interactions in the community

Mandibular and Neural Crest Cell Deficits Seen in TsDn65 Down Syndrome Mouse Model Rescued By Green Tea Polyphenol, EGCG

poster abstractDown Syndrome (DS) is caused by trisomy of the human chromosome 21 (Hsa21) and occurs in ~1 of every 700 births. DS is distinguished by over 80 phenotypic abnormalities including skeletal deficits and craniofacial phenotypes characterized by a flattened skull, slanted eyes, and a smaller mandible. To study these abnormalities, we utilize the Ts65Dn DS mouse model containing a triplication of approximately half of the gene homologues found on Hsa21 and mirrors the skeletal and mandibular phenotypes observed in DS. In Ts65Dn mice, the origin of the mandibular deficits were traced to a reduction in size of the 1st branchial arch (BA1), the developmental precursor to the mandible, occurring at embryonic day 9.5 (E9.5). At E9.5, we observe a lack of proliferation and migration of neural crest cells (NCC) from the neural tube (NT) into the BA1, causing a reduced BA1. We hypothesize that an overexpression of Dyrk1a, a Hsa21 homologue, contributes to the mandibular deficit seen in E9.5 Ts65Dn embryos. We propose that EGCG, a green tea polyphenol, will inhibit DYRK1a activity, rescuing the BA1 deficit. To test our hypothesis, Ts65Dn mothers were treated with EGCG from E0-E9.5 and sacrificed to retrieve the E9.5 embryos. Our results from unbiased stereological assessments show that E0-E9.5 EGCG in vivo treatment has the potential to increase NCC number, BA1 volume, and embryo volume of trisomic embryos. This data provide preclinical testing for a potential therapy of DS craniofacial disorders, which may extend to treating bone deficits in DS and osteoporosis

The Ursinus Weekly, November 6, 1950

Kunkel tells IRC forum conditions in Europe good • MSGA proposes dorm government; Will ask approval • Students hear Yost read Frost\u27s poetry at Tuesday program • Popowich elected to MSGA • Englishman to discuss labor economy tonight • Record room opens • Newman Club to dine • Graf, Roberts get Curtain Club roles in Angel Street • Y Commission plans toy, clothing drive • Weekly adds seventeen to staff, nine freshmen • Como to give concert • Local sororities announce acceptance of 48 women • Wagner to speak Sunday at Trinity worship service • Rev. Harris to address Y association meeting • Juniors to choose heads of \u2752 Ruby during November • Approximately 150 castaways attend Juniors\u27 Shipwreck Ball • To conduct hymn sing • Editorial: Outlet for enthusiasm • Speaker and square dance to highlight annual World Student Service Drive • Miss Maroney is capable librarian • Do changing world conditions require new college courses? • Ruby show next weekend to reveal true nature of conditions in Hades • Saporoschenko reveals facts about red regime • Gunther writes Roosevelt in retrospect, revealing and unorthodox biography • Bruins to oppose Adelphi Panthers on Patterson Field • Basketball squad works out daily • Girls\u27 third team beats Temple 2-1 and ties Penn 2-2 • Belles win three in tournament; Vadner honored • Soccer team loses to Haverford, 8-1 • Fords down Bears in X-country • F & M routs Bears 39-0 as Lowder paces attack • To present German play • Rosicrucians to give teahttps://digitalcommons.ursinus.edu/weekly/1551/thumbnail.jp