High-temperature thermal storage systems for advanced solar receivers materials selections

Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquid temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi2, and initial results for containment of germanium and NiSi/NiSi2, are presented

Inclusive measurements with MINER nu A

MINER nu A is a neutrino scattering experiment in the NuMI beamline at Fermilab designed to measure neutrino cross-sections, final states and nuclear effects on a variety of targets in the few-GeV region. MINER nu A is currently running in the NuMI low energy configuration and will continue in medium energy. We present a preliminary neutrino energy spectra in three beam configurations and a preliminary comparison of iron and lead event rates

Caveolin-1 expression is elevated in claudin-low mammary tumor cells

<p>Abstract</p> <p>Background</p> <p>Caveolin-1 is a scaffolding protein found in plasma membrane invaginations known as caveolae. Caveolin-1 can regulate a number of intracellular processes such as signal transduction, cholesterol metabolism and vesicular transport. With respect to breast cancer caveolin-1 has been observed in both tumor cells and stromal cells surrounding tumors however most of the recent research has focused on how the loss of caveolin-1 in the stromal cells surrounding the tumor alters the tumor microenvironment.</p> <p>Methods</p> <p>Caveolin-1 expression was evaluated in (1) mammary tumors induced by the transgenic overexpression of the type I insulin-like growth factor receptor (IGF-IR), (2) mammary tumors that became independent of IGF-IR signalling and acquired a claudin-low genotype, (3) two murine mammary epithelial tumor cell lines and (4) two murine mammary claudin-low tumor cell lines.</p> <p>Results</p> <p>We found that mammary tumors induced by IGF-IR overexpression expressed low levels of caveolin-1 while mammary tumors that became independent of IGF-IR signalling expressed considerably higher levels of caveolin-1. Interestingly, pockets of caveolin-1 positive cells could be observed in some of the IGF-IR-induced mammary tumors and these caveolin-1 positive cells were associated with tumor cells that expressed basal cytokeratins (cytokeratins 5 and 14). This caveolin-1 expression pattern was maintained in the murine mammary tumor cell lines in that the epithelial mammary tumor cell lines expressed little or no caveolin-1 while the claudin-low cell lines expressed caveolin-1.</p> <p>Conclusions</p> <p>Our model indicates that mammary tumor cells with epithelial characteristics lack caveolin-1 while mesenchymal tumor cells express caveolin-1 suggesting that caveolin-1 may serve as a marker of mammary tumor cells with mesenchymal characteristics such as claudin-low breast tumors.</p

TINGKAT KERAGAMAN DAN DENSITAS HOMOPTERA DI KEBUN BLAWAN (PTPN XII) BONDOWOSO SERTA PEMANFAATANNYA DALAM PENYUSUNAN BUKU PANDUAN LAPANG HOMOPTERA

Abstract Biology learning is a learning that not only focused on knowledge aspecs, but also focused on how to discover process that happened in biology. One effort to discover biology process is by using environment as learning source. This research aims is to analyze diversity and density of Homoptera in Kebun Blawan Bondowoso and use it to develop Homopteran field guide book as learning source alternative. Research method is by collecting data about Homopteran insect in Kebun Blawan Bondowoso, then used as material to develop field guide book. The book then evaluated to know how proper the book to used as learning source by school students. Based on analysis, diversity of Homoptera in Kebun Blawan are 2,20 and the density are 13,00 individu per plot. Based on evaluation, score of Homopteran field guide book are 83, which mean the book is recommended as a learning source alternative for students. Keywords: Diversity, density, field guide book, Homopter

MINIMIZING THE ADVERSE EFFECTS OF WORK ENVIRONMENT IN UPPER LIMB: A LITERATURE REVIEW

Introduction: Occupational problems are highly prevalent and act as impediments to effective labor. As per the statistics by WHO, in the year 2003, it was seen that back injuries shared the highest proportion in occupational disorders (60%), followed by neck and upper limb. Body: In the upper limb, any joint, be it the shoulder, elbow, wrist or hand, can be affected. Variable structures ranging from the tendon, ligament, nerve or muscle can be involved leading to problems effectuating in the form of pain, tenderness, swelling, and functional deficits. Common problems seen are carpal tunnel syndrome, muscle sprain-strain, and osteoarthritis in joints, etc. Management: ULMSDS can be prevented by incorporating activity in daily life awhile also keeping a check on posture. At workplace, architectural adjustments and changes in physical and social environment can help prevention exacerbation of upper limb conditions. Regular rest intervals can also be included to avoid prolonged fixation of joints in one position. Conclusion: This paper focuses on ULMSDS in an attempt to improve the quality of life through various intervention strategies within the work organization thus enhancing work quality and output of the companies. Article visualizations

Measurement of muon plus proton final states in nu(mu) interactions on hydrocarbon at \u3c E-nu \u3e=4.2 GeV

A study of charged-current muon neutrino scattering on hydrocarbon in which the final state includes a muon, at least one proton, and no pions is presented. Although this signature has the topology of neutrino quasielastic scattering from neutrons, the event sample contains contributions from quasielastic and inelastic processes where pions are absorbed in the nucleus. The analysis accepts events with muon production angles up to 70 degrees and proton kinetic energies greater than 110 MeV. The cross section, when based completely on hadronic kinematics, is well described by a relativistic Fermi gas nuclear model including the neutrino event generator modeling for inelastic processes and particle transportation through the nucleus. This is in contrast to the quasielastic cross section based on muon kinematics, which is best described by an extended model that incorporates multinucleon correlations. This measurement guides the formulation of a complete description of neutrino-nucleus interactions that encompasses the hadronic as well as the leptonic aspects of this process

Measurement of Electron Neutrino Quasielastic and Quasielasticlike Scattering on Hydrocarbon at \u3c E-v \u3e=3.6 GeV

The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q(2) are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q(2) for v(e) with that of similarly selected v(mu)-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current v(e) interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE

Evidence for Neutral-Current Diffractive pi(0) Production from Hydrogen in Neutrino Interactions on Hydrocarbon

The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current pi(0) production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26 +/- 0.02(stat.) +/- 0.08(sys.) x 10(-39) cm(2). The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive pi(0) production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino-oscillation experiments searching for nu(mu) to nu(e) oscillations

Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current nu(mu) interactions is combined with muon kinematics to permit separation of the quasielastic and Delta(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Delta resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments