Sample records for kanbenna panel ho

  1. Ferroelectricity and competing interactions in Ho-deficient non-stoichiometric orthorhombic HoMnO{sub 3}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, J. X.; Yan, Z. B.; Xie, Y. L.

    2015-05-07

    We investigate the consequences of the Ho-deficient non-stoichiometry in orthorhombic HoMnO{sub 3} in terms of microscopic mechanisms for ferroelectricity modulation. It is suggested that the Ho-deficiency (then Mn excess) results in Ho-vacancies and then Mn occupation of the Ho-site with increasing non-stoichiometry. The Ho-deficiency enhances the Mn-Mn symmetric exchange striction by suppressing the independent Ho-Ho interaction, and thus benefits to the induced Ho spin ordering against the independent Ho spin ordering. The symmetric Ho-Mn exchange striction is thus enhanced by this induced Ho spin ordering, leading to remarkably enhanced ferroelectric polarization as observed. This work presents an alternative scheme tomore » modulate the multiferroicity in rare-earth manganites of strong 4f-3d coupling.« less

  2. HO:LULF and HO:LULF Laser Materials

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P. (Inventor); Morrison, Clyde A. (Inventor); Filer, Elizabeth D. (Inventor); Jani, Mahendra G. (Inventor); Murray, Keith E. (Inventor); Lockard, George E. (Inventor)

    1998-01-01

    A laser host material LULF (LuLiF4) is doped with holmium (Ho) and thulium (Tm) to produce a new laser material that is capable of laser light production in the vicinity of 2 microns. The material provides an advantage in efficiency over conventional Ho lasers because the LULF host material allows for decreased threshold and upconversion over such hosts as YAG and YLF. The addition of Tm allows for pumping by commonly available GaAlAs laser diodes. For use with flashlamp pumping, erbium (Er) may be added as an additional dopant. For further upconversion reduction, the Tm can be eliminated and the Ho can be directly pumped.

  3. Spectroscopy and microchip laser operation of Tm, Ho:KYW crystals with different Ho concentrations

    NASA Astrophysics Data System (ADS)

    Gusakova, N. V.; Kurilchik, S. V.; Yasukevich, A. S.; Kisel, V. E.; Dashkevich, V. I.; Orlovich, V. A.; Pavlyuk, A. A.; Vatnik, S. M.; Bagaev, S. N.; Kuleshov, N. V.

    2018-02-01

    The spectroscopic properties of Tm, Ho:KYW crystals with different Ho concentrations were investigated. The diode-pumped microchip laser operation of Tm (5 at.%), Ho (0.5 at.%):KYW and Tm (5 at.%), Ho (1 at.%):KYW was demonstrated. The highest, to our knowledge, output power of 480 mW with slope efficiency of 31% for CW Tm (5 at.%), Ho (0.5 at.%):KYW microchip laser was obtained.

  4. Cerebroprotective functions of HO-2.

    PubMed

    Parfenova, Helena; Leffler, Charles W

    2008-01-01

    The constitutive isoform of heme oxygenase, HO-2, is highly expressed in the brain and in cerebral vessels. HO-2 functions in the brain have been evaluated using pharmacological inhibitors of the enzyme and HO-2 gene deletion in in vivo animal models and in cultured cells (neurons, astrocytes, cerebral vascular endothelial cells). Rapid activation of HO-2 via post-translational modifications without upregulation of HO-2 expression or HO-1 induction coincides with the increase in cerebral blood flow aimed at maintaining brain homeostasis and neuronal survival during seizures, hypoxia, and hypotension. Pharmacological inhibition or gene deletion of brain HO-2 exacerbates oxidative stress induced by seizures, glutamate, and inflammatory cytokines, and causes cerebral vascular injury. Carbon monoxide (CO) and bilirubin, the end products of HO-catalyzed heme degradation, have distinct cytoprotective functions. CO, by binding to a heme prosthetic group, regulates the key components of cell signaling, including BK(Ca) channels, guanylyl cyclase, NADPH oxidase, and the mitochondria respiratory chain. Cerebral vasodilator effects of CO are mediated via activation of BK(Ca) channels and guanylyl cyclase. CO, by inhibiting the major components of endogenous oxidant-generating machinery, NADPH oxidase and the cytochrome C oxidase of the mitochondrial respiratory chain, blocks formation of reactive oxygen species. Bilirubin, via redox cycling with biliverdin, is a potent oxidant scavenger that removes preformed oxidants. Overall, HO-2 has dual housekeeping cerebroprotective functions by maintaining autoregulation of cerebral blood flow aimed at improving neuronal survival in a changing environment, and by providing an effective defense mechanism that blocks oxidant formation and prevents cell death caused by oxidative stress.

  5. HOED: Hypermedia Online Educational Database.

    ERIC Educational Resources Information Center

    Duval, E.; Olivie, H.

    This paper presents HOED, a distributed hypermedia client-server system for educational resources. The aim of HOED is to provide a library facility for hyperdocuments that is accessible via the world wide web. Its main application domain is education. The HOED database not only holds the educational resources themselves, but also data describing…

  6. Minfong Ho: Politics in Prose

    ERIC Educational Resources Information Center

    Wiggins, Joy L.

    2006-01-01

    In this article, the author interviews Minfong Ho, an award-winning Thai writer of children's and young adult novels. Ho was born in Burma to Chinese parents in 1951, raised in Singapore and Thailand, educated in Bangkok, Taiwan, and at Cornell University in New York. Ho's first novel, "Sing to the Dawn," won first prize from the Council of…

  7. High Energy Directly Pumped Ho:YLF Laser

    NASA Technical Reports Server (NTRS)

    Petros, Mulugeta; Yu, Ji-Rong; Singh, Upendra N.; Barnes, Norman P.

    2000-01-01

    The most commonly used crystal architecture to produce 2 micrometer laser is co-doping Ho and Tm into a single host crystal. In this method, the stored energy transfer from the Tm (3)F4 to the Ho (5)I7 manifold is not fast enough to warrant high efficiency for short pulse applications. By separating the Ho and the Tm ions and doping the Tm in YALO3 and the Ho in YLF, we were able to directly pump the Ho (5)I7 manifold with 1.94 micrometers. The Ho:YLF laser has produced 33 mJ at 2.062 micrometers with a quantum efficiency of 0.88. The performance of each laser will be presented.

  8. Actively mode-locked Tm-Ho:LiYF4 and Tm-Ho:BaY2F8 lasers

    NASA Astrophysics Data System (ADS)

    Gatti, D.; Galzerano, G.; Toncelli, A.; Tonelli, M.; Laporta, P.

    2007-01-01

    We report on the generation of mode-locking pulse trains with high average output powers from diode-pumped Tm-Ho:LiYF4 and Tm-Ho:BaY2F8 lasers emitting at around 2 μm. The highest output power of 365 mW was obtained with the Tm-Ho:YLF4 laser, whereas the shortest pulse duration of 120 ps and the widest tunability range of 59 nm was achieved with the Tm-Ho:BaY2F8 laser.

  9. Topics in Ho Morphophonology and Morphosyntax

    ERIC Educational Resources Information Center

    Pucilowski, Anna

    2013-01-01

    Ho, an under-documented North Munda language of India, is known for its complex verb forms. This dissertation focuses on analysis of several features of those complex verbs, using data from original fieldwork undertaken by the author. By way of background, an analysis of the phonetics, phonology and morphophonology of Ho is first presented. Ho has…

  10. Homozygous familial hypercholesterolaemia: new insights and guidance for clinicians to improve detection and clinical management. A position paper from the Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society

    PubMed Central

    Cuchel, Marina; Bruckert, Eric; Ginsberg, Henry N.; Raal, Frederick J.; Santos, Raul D.; Hegele, Robert A.; Kuivenhoven, Jan Albert; Nordestgaard, Børge G.; Descamps, Olivier S.; Steinhagen-Thiessen, Elisabeth; Tybjærg-Hansen, Anne; Watts, Gerald F.; Averna, Maurizio; Boileau, Catherine; Borén, Jan; Catapano, Alberico L.; Defesche, Joep C.; Hovingh, G. Kees; Humphries, Steve E.; Kovanen, Petri T.; Masana, Luis; Pajukanta, Päivi; Parhofer, Klaus G.; Ray, Kausik K.; Stalenhoef, Anton F. H.; Stroes, Erik; Taskinen, Marja-Riitta; Wiegman, Albert; Wiklund, Olov; Chapman, M. John; Cuchel, Marina; Bruckert, Eric; Chapman, M. John; Descamps, Olivier S.; Ginsberg, Henry N.; Hegele, Robert A.; Kuivenhoven, Jan Albert; Nordestgaard, Børge G.; Raal, Frederick J.; Santos, Raul D.; Steinhagen-Thiessen, Elisabeth; Tybjærg-Hansen, Anne; Watts, Gerald F.; Chapman, M. John; Ginsberg, Henry N.; Averna, Maurizio; Boileau, Catherine; Borén, Jan; Catapano, Alberico L.; Defesche, Joep C.; Hovingh, G. Kees; Humphries, Steve E.; Kovanen, Petri T.; Masana, Luis; Pajukanta, Päivi; Parhofer, Klaus G.; Ray, Kausik K.; Stalenhoef, Anton F. H.; Stroes, Erik; Taskinen, Marja-Riitta; Wiegman, Albert; Wiklund, Olov

    2014-01-01

    Aims Homozygous familial hypercholesterolaemia (HoFH) is a rare life-threatening condition characterized by markedly elevated circulating levels of low-density lipoprotein cholesterol (LDL-C) and accelerated, premature atherosclerotic cardiovascular disease (ACVD). Given recent insights into the heterogeneity of genetic defects and clinical phenotype of HoFH, and the availability of new therapeutic options, this Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society (EAS) critically reviewed available data with the aim of providing clinical guidance for the recognition and management of HoFH. Methods and results Early diagnosis of HoFH and prompt initiation of diet and lipid-lowering therapy are critical. Genetic testing may provide a definitive diagnosis, but if unavailable, markedly elevated LDL-C levels together with cutaneous or tendon xanthomas before 10 years, or untreated elevated LDL-C levels consistent with heterozygous FH in both parents, are suggestive of HoFH. We recommend that patients with suspected HoFH are promptly referred to specialist centres for a comprehensive ACVD evaluation and clinical management. Lifestyle intervention and maximal statin therapy are the mainstays of treatment, ideally started in the first year of life or at an initial diagnosis, often with ezetimibe and other lipid-modifying therapy. As patients rarely achieve LDL-C targets, adjunctive lipoprotein apheresis is recommended where available, preferably started by age 5 and no later than 8 years. The number of therapeutic approaches has increased following approval of lomitapide and mipomersen for HoFH. Given the severity of ACVD, we recommend regular follow-up, including Doppler echocardiographic evaluation of the heart and aorta annually, stress testing and, if available, computed tomography coronary angiography every 5 years, or less if deemed necessary. Conclusion This EAS Consensus Panel highlights the need for early identification of Ho

  11. Homozygous familial hypercholesterolaemia: new insights and guidance for clinicians to improve detection and clinical management. A position paper from the Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society.

    PubMed

    Cuchel, Marina; Bruckert, Eric; Ginsberg, Henry N; Raal, Frederick J; Santos, Raul D; Hegele, Robert A; Kuivenhoven, Jan Albert; Nordestgaard, Børge G; Descamps, Olivier S; Steinhagen-Thiessen, Elisabeth; Tybjærg-Hansen, Anne; Watts, Gerald F; Averna, Maurizio; Boileau, Catherine; Borén, Jan; Catapano, Alberico L; Defesche, Joep C; Hovingh, G Kees; Humphries, Steve E; Kovanen, Petri T; Masana, Luis; Pajukanta, Päivi; Parhofer, Klaus G; Ray, Kausik K; Stalenhoef, Anton F H; Stroes, Erik; Taskinen, Marja-Riitta; Wiegman, Albert; Wiklund, Olov; Chapman, M John

    2014-08-21

    Homozygous familial hypercholesterolaemia (HoFH) is a rare life-threatening condition characterized by markedly elevated circulating levels of low-density lipoprotein cholesterol (LDL-C) and accelerated, premature atherosclerotic cardiovascular disease (ACVD). Given recent insights into the heterogeneity of genetic defects and clinical phenotype of HoFH, and the availability of new therapeutic options, this Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society (EAS) critically reviewed available data with the aim of providing clinical guidance for the recognition and management of HoFH. Early diagnosis of HoFH and prompt initiation of diet and lipid-lowering therapy are critical. Genetic testing may provide a definitive diagnosis, but if unavailable, markedly elevated LDL-C levels together with cutaneous or tendon xanthomas before 10 years, or untreated elevated LDL-C levels consistent with heterozygous FH in both parents, are suggestive of HoFH. We recommend that patients with suspected HoFH are promptly referred to specialist centres for a comprehensive ACVD evaluation and clinical management. Lifestyle intervention and maximal statin therapy are the mainstays of treatment, ideally started in the first year of life or at an initial diagnosis, often with ezetimibe and other lipid-modifying therapy. As patients rarely achieve LDL-C targets, adjunctive lipoprotein apheresis is recommended where available, preferably started by age 5 and no later than 8 years. The number of therapeutic approaches has increased following approval of lomitapide and mipomersen for HoFH. Given the severity of ACVD, we recommend regular follow-up, including Doppler echocardiographic evaluation of the heart and aorta annually, stress testing and, if available, computed tomography coronary angiography every 5 years, or less if deemed necessary. This EAS Consensus Panel highlights the need for early identification of HoFH patients, prompt referral to

  12. AN ELISA ASSAY FOR HEME OXYGENASE (HO-1)

    EPA Science Inventory

    An ELISA assay for heme oxygenase (HO-l )

    Abstract

    A double antibody capture ELISA for the HO-l protein has been developed to separately quantitate HO-I protein. The use of 2.5% NP40 detergent greatly assists in freeing HO-l protein from membranes and/or other cel...

  13. Apo A1 Mimetic Rescues the Diabetic Phenotype of HO-2 Knockout Mice via an Increase in HO-1 Adiponectin and LKBI Signaling Pathway

    PubMed Central

    Cao, Jian; Puri, Nitin; Sodhi, Komal; Bellner, Lars; Abraham, Nader G.; Kappas, Attallah

    2012-01-01

    Insulin resistance, with adipose tissue dysfunction, is one of the hallmarks of metabolic syndrome. We have reported a metabolic syndrome-like phenotype in heme oxygenase (HO)-2 knockout mice, which presented with concurrent HO-1 deficiency and were amenable to rescue by an EET analog. Apo A-I mimetic peptides, such as L-4F, have been shown to induce HO-1 expression and decrease oxidative stress and adiposity. In this study we aimed to characterize alleviatory effects of HO-1 induction (if any) on metabolic imbalance observed in HO-2 KO mice. In this regard, HO-2(−/−) mice were injected with 2 mg/kg/day L-4F, or vehicle, i.p., for 6 weeks. As before, compared to WT animals, the HO-2 null mice were obese, displayed insulin resistance, and had elevated blood pressure. These changes were accompanied by enhanced tissue (hepatic) oxidative stress along with attenuation of HO-1 expression and activity and reduced adiponectin, pAMPK, and LKB1 expression. Treatment with L-4F restored HO-1 expression and activity and increased adiponectin, LKB1, and pAMPK in the HO-2(−/−) mice. These alterations resulted in a decrease in blood pressure, insulin resistance, blood glucose, and adiposity. Taken together, our results show that a deficient HO-1 response, in a state with reduced HO-2 basal levels, is accompanied by disruption of metabolic homeostasis which is successfully restored by an HO-1 inducer. PMID:22577519

  14. K2Ho(PO4)(WO4)

    PubMed Central

    Terebilenko, Katherina V.; Zatovsky, Igor V.; Baumer, Vyacheslav N.; Slobodyanik, Nikolay S.; Shishkin, Oleg V.

    2008-01-01

    A new compound, dipotassium holmium(III) phosphate(V) tungstate(VI), K2Ho(PO4)(WO4), has been obtained during investigation of the K2O–P2O5–WO3–HoF3 phase system using the flux technique. The compound is isotypic with K2Bi(PO4)(WO4). Its framework structure consists of flat ∞ 2[HoPO4] layers parallel to (100) that are made up of ∞ 1[HoO8] zigzag chains inter­linked via slightly distorted PO4 tetra­hedra. WO4 tetra­hedra are attached above and below these layers, leaving space for the K+ counter-cations. The HoO8, PO4 and WO4 units exhibit 2 symmetry. PMID:21580811

  15. Phase relations in the system Cu-Ho-O and stability of Cu{sub 2}Ho{sub 2}O{sub 5}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matthews, T.; Jacob, K.T.

    1994-01-01

    The phase relations in the system Cu-Ho-O have been determined at 1300 K using X-ray diffraction, optical microscopy, and electron microprobe analysis of samples equilibrated in evacuated quartz ampules and in pure oxygen. Only one ternary compound, Cu{sub 2}Ho{sub 2}O{sub 5}, was found to be stable. The Gibbs free energy of formation of this compound has been measured. Since the formation is endothermic, Cu{sub 2}Ho{sub 2}O{sub 5} becomes thermodynamically unstable with respect to CuO and Ho{sub 2}O{sub 3} below 810 K. When the oxygen partial pressure over Cu{sub 2}Ho{sub 2}O{sub 5} is lowered, it decomposes. The decomposition temperature at anmore » oxygen partial pressure of 1.52 X 10{sup 4} Pa was measured using a combined DTA-TGA apparatus. Based on these results, an oxygen potential diagram for the system Cu-Ho-O at 1300 K is presented.« less

  16. Ablation of porcine ligamentum flavum with Ho:YAG, q-switched Ho:YAG, and quadrupled Nd:YAG lasers.

    PubMed

    Johnson, Matt R; Codd, Patrick J; Hill, Westin M; Boettcher, Tara

    2015-12-01

    Ligamentum flavum (LF) is a tough, rubbery connective tissue providing a portion of the ligamentous stability to the spinal column, and in its hypertrophied state forms a significant compressive pathology in degenerative spinal stenosis. The interaction of lasers and this biological tissue have not been thoroughly studied. Technological advances improving endoscopic surgical access to the spinal canal makes selective removal of LF using small, flexible tools such as laser-coupled fiber optics increasingly attractive for treatment of debilitating spinal stenosis. Testing was performed to assess the effect of Ho:YAG, Q-switched Ho:YAG, and frequency quadrupled Nd:YAG lasers on samples of porcine LF. The objective was to evaluate the suitability of these lasers for surgical removal of LF. LF was resected from porcine spine within 2 hours of sacrifice and stored in saline until immediately prior to laser irradiation, which occurred within an additional 2 hours. The optical absorbance of a sample was measured over the spectral band from 190 to 2,360 nm both before and after dehydration. For the experiments using the Ho:YAG (λ = 2,080 nm, tp  = 140 µs, FWHM) and Q-Switched Ho:YAG (λ = 2,080 nm, tp  = 260 ns, FWHM) lasers, energy was delivered to the LF through a laser-fiber optic with 600 µm core and NA = 0.39. For the experiment using the frequency quadrupled Nd:YAG laser (λ = 266 nm, tp  = 5 ns FWHM), rather than applying the laser energy through a laser-fiber, the energy was focused through an aperture and lens directly onto the LF. Five experiments were conducted to evaluate the effect of the given lasers on LF. First, using the Ho:YAG laser, the single-pulse laser-hole depth versus laser fluence was measured with the laser-fiber in direct contact with the LF (1 g force) and with a standoff distance of 1 mm between the laser-fiber face and the LF. Second, with the LF remaining in situ and the spine bisected

  17. Local Measurement of Tropospheric HO(x)

    NASA Technical Reports Server (NTRS)

    Crosley, David R.

    1994-01-01

    In March of 1992 a workshop sponsored by NASA and NSF was held at SRI International to assess the current ability to measure atmospheric OH and HO2. The measurement techniques reviewed during the workshop for detection of OH included five laser-induced fluorescence schemes, five laser-based adsorption techniques, and four non-laser methods. Six instruments or instrument concepts for HO2 detection, including chemical amplification, conversion to OH with subsequent OH detection, or direct spectroscopic detection of the HO2 were also discussed. The conclusions from the workshop identify several measurement techniques for OH and HO2 that are ready for field tests. These have the ability to measure the radicals with sufficient sensitivity and accuracy to form meaningful comparison with atmospheric model predictions. The workshop conclusions also include recommendations for informal and formal intercomparison protocols.

  18. Predicting the risk for hospital-onset Clostridium difficile infection (HO-CDI) at the time of inpatient admission: HO-CDI risk score.

    PubMed

    Tabak, Ying P; Johannes, Richard S; Sun, Xiaowu; Nunez, Carlos M; McDonald, L Clifford

    2015-06-01

    To predict the likelihood of hospital-onset Clostridium difficile infection (HO-CDI) based on patient clinical presentations at admission Retrospective data analysis Six US acute care hospitals Adult inpatients We used clinical data collected at the time of admission in electronic health record (EHR) systems to develop and validate a HO-CDI predictive model. The outcome measure was HO-CDI cases identified by a nonduplicate positive C. difficile toxin assay result with stool specimens collected >48 hours after inpatient admission. We fit a logistic regression model to predict the risk of HO-CDI. We validated the model using 1,000 bootstrap simulations. Among 78,080 adult admissions, 323 HO-CDI cases were identified (ie, a rate of 4.1 per 1,000 admissions). The logistic regression model yielded 14 independent predictors, including hospital community onset CDI pressure, patient age ≥65, previous healthcare exposures, CDI in previous admission, admission to the intensive care unit, albumin ≤3 g/dL, creatinine >2.0 mg/dL, bands >32%, platelets ≤150 or >420 109/L, and white blood cell count >11,000 mm3. The model had a c-statistic of 0.78 (95% confidence interval [CI], 0.76-0.81) with good calibration. Among 79% of patients with risk scores of 0-7, 19 HO-CDIs occurred per 10,000 admissions; for patients with risk scores >20, 623 HO-CDIs occurred per 10,000 admissions (P<.0001). Using clinical parameters available at the time of admission, this HO-CDI model demonstrated good predictive ability, and it may have utility as an early risk identification tool for HO-CDI preventive interventions and outcome comparisons.

  19. The Ho-Ni-Ge system: Isothermal section and new rare-earth nickel germanides

    NASA Astrophysics Data System (ADS)

    Morozkin, A. V.; Knotko, A. V.; Yapaskurt, V. O.; Yuan, Fang; Mozharivskyj, Y.; Pani, M.; Provino, A.; Manfrinetti, P.

    2015-05-01

    The Ho-Ni-Ge system has been investigated at 1070 K and up to 60 at% Ho by X-ray diffraction and microprobe analyses. Besides the eight known compounds, HoNi5Ge3 (YNi5Si3-type), HoNi2Ge2 (CeAl2Ga2-type), Ho2NiGe6 (Ce2CuGe6-type), HoNiGe3 (SmNiGe3-type), HoNi0.2÷0.6Ge2 (CeNiSi2-type), Ho37÷34Ni6÷24Ge57÷42 (AlB2-type), HoNiGe (TiNiSi-type), Ho3NiGe2 (La3NiGe2-type), the ternary system contains four new compounds: Ho3Ni11Ge4 (Sc3Ni11Ge4-type), HoNi3Ge2 (ErNi3Ge2-type), Ho3Ni2Ge3 (Hf3Ni2Si3-type) and Ho5Ni2Ge3 (unknown structure). Quasi-binary solid solutions were observed at 1070 K for Ho2Ni17, HoNi5, HoNi7, HoNi3, HoNi2, HoNi and Ho2Ge3, but no detectable solubility was found for the other binary compounds in the Ho-Ni-Ge system. Based on the magnetization measurements, the HoNi5Ge3, HoNi3Ge2 and Ho3Ni11Ge4 (and isostructural {Tb, Dy}3Ni11Ge4) compounds have been found to show paramagnetic behavior down to 5 K, whereas Ho3Ni2Ge3 exhibits an antiferromagnetic transition at 7 K. Additionally, the crystal structure of the new isostructural phases {Y, Yb}Ni3Ge2 (ErNi3Ge2-type), Er3Ni11Ge4 (Sc3Ni11Ge4-type) and {Y, Tb, Dy, Er, Tm}3Ni2Ge3 (Hf3Ni2Si3-type) has been also investigated.

  20. Holmium laser lithotripsy (HoLL) of ureteral calculi

    NASA Astrophysics Data System (ADS)

    Kuntz, Rainer M.; Lehrich, Karin; Fayad, Amr

    2001-05-01

    The effectiveness and side effects of ureteroscopic HoLL of ureteral stones should be evaluated. In 63 patients (17 female, 46 males) a total of 75 stones of 3-20 mm diameter were treated with ureteroscopic HoLL. 18.7 percent of stones were located in the proximal third, 24.0 percent in the middle third and 57.3 percent in the distal third of the ureter. HoLL was performed with small diameter semirigid and flexible ureteroscopes, 220 or 365 nm flexible laser fibers and a holmium:YAG laser at a power of 5-15 W (0.5-1.0 J, 10- 15 Hz). 47 of 63 patients (74.6 percent) were immediately free of stones, and 8 others (12.6 percent) lost their residual fragments spontaneously within two weeks. Another 2 patients received additional chmolitholysis for uric acid stone fragments, i.e. 90.5 percent of patients were stone free by one sitting of ureterscopic HoLL. Of the remaining 6 patients (9.5 percent) who still had residual calculi 4 weeks after HoLL, 2 asymptomatic patients refused any additional treatment, 2 patients preferred treatment with ESWL, and 2 patients had a successful second HoLL, thereby raising the success rate of ureteroscopic HoLL to 93.7 percent. 2 patients showed contrast medium extravasation on retrograde ureterograms, due to guide wire perforation. No ureteral stricture occurred. In conclusion, transurethral ureteroscopic HoLL proved to be a safe and successful minimal invasive treatment of ureteral calculi.

  1. Measurement of HO2 chemical kinetics with a new detection method

    NASA Technical Reports Server (NTRS)

    Lee, Long C.; Suto, Masako

    1986-01-01

    Reaction rate constants of HO2+O3 were measured at various temperatures using a newly developed HO2 detection method. HO2 was detected by the OH(A-X) emission produced from photodissociative excitation of HO2 at 147 nm. In order to examine the possible interference of other emitting species with the HO2 detection, the photoexcitation processes of all the chemical species existing in the discharge flow tube were also investigated. The results are summarized.

  2. Efficient upconversion emission in Ho3+/Nd3+ co-doped oxyfluorosilicate glasses

    NASA Astrophysics Data System (ADS)

    Devarajulu, G.; Raju, B. Deva Prasad

    2018-04-01

    We report on an efficient Ho3+ and Ho3+/Nd3+ co-doped oxyfluorosilicate glasses upon excitation with an 808 nm laser diode. The detailed fluorescence have been studied under this excitation source and energy transfer mechanisms in Ho3+/Nd3+ co-doped oxyfluorosilicate glasses. The upconversion peaks at 486, 547 and 596 nm were observed in Nd3+/Ho3+ co-doped sample. The intensity of upconversion emission transitions in Ho3+ depends on the neodymium codopent concentration. These results indicate that Nd3+ ions can be potentially used as sensitizer for Ho3+ ions to stimulate the intense upconversion emission. The energy transfer mechanism between Nd3+ and Ho3+ was analyzed pursuant to the absorption spectra, upconversion spectra and the energy level structures of Nd3+ and Ho3+ ions have been briefly discussed.

  3. 75 FR 52534 - Su Van Ho: Debarment Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Salmonella bacteria, with verification of such exportation or destruction by FDA. Mr. Ho concealed and... with Salmonella bacteria. As a result of his conviction, on June 10, 2010, FDA sent Mr. Ho a notice by...

  4. AN ENZYME LINKED IMMUNOSORBENT ASSAY FOR THE HO-1 ISOFORM OF HEME OXYGENASE

    EPA Science Inventory

    AN ENZYME LINKED IMMUNOSORBENT ASSAY FOR THE HO-1 ISOFORM OF HEME OXYGENASE

    Heme oxygenase (HO) occurs in biological tissues as two major isoforms HO-1 and HO-2. HO-1 is inducible by many treatments, particularly oxidative stress-related conditions such as depletion of gl...

  5. EGR-1 regulates Ho-1 expression induced by cigarette smoke

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Huaqun, E-mail: chenhuaqun@njnu.edu.cn; Wang, Lijuan; Gong, Tao

    2010-05-28

    As an anti-oxidant molecule, heme oxygenase-1 (HO-1) has been implicated in the protection of lung injury by cigarette smoke (CS). The mechanisms regulating its expression have not been defined. In this report, the role of early growth response 1 (EGR-1) in the regulation of Ho-1 expression was investigated. In C57BL/6 mice with CS exposure, HO-1 was greatly increased in bronchial epithelial cells and alveolar inflammatory cells. In primary cultured mouse lung fibroblasts and RAW264.7 cells exposed to cigarette smoke water extract (CSE), an increase in HO-1 protein level was detected. In addition, CSE induced HO-1 expression was decreased in Egr-1more » deficient mouse embryo fibroblasts (Egr-1{sup -/-} MEFs). Nuclear localization of EGR-1 was examined in mouse lung fibroblasts after exposure to CSE. Luciferase reporter activity assays showed that the enhancer region of the Ho-1 gene containing a proposed EGR-1 binding site was responsible for the induction of HO-1. A higher increase of alveolar mean linear intercept (Lm) was observed in lung tissues, and a larger increase in the number of total cells and monocytes/macrophages from bronchial alveolar lavage fluid was found in CS-exposed mice by loss of function of EGR-1 treatment. In summary, the present data demonstrate that EGR-1 plays a critical role in HO-1 production induced by CS.« less

  6. Ho-nanoparticle-doping for improved high-energy laser fibers

    NASA Astrophysics Data System (ADS)

    Friebele, E. Joseph; Baker, Colin C.; Burdett, Ashley A.; Rhonehouse, Daniel L.; Bowman, Steven R.; Kim, Woohong; Sanghera, Jasbinder S.; Kucera, Courtney; Vargas, Amber; Ballato, John; Hemming, Alexander; Simakov, Nikita; Haub, John

    2017-02-01

    A significant issue for holmium-doped fiber lasers (HoDFLs) operating near 2 μm is multiphonon quenching due to the high phonon energy 1100 cm-1 of the silica host, which complicates power scaling due to reduced lifetimes and increased heating. Nanoparticle (NP) doping is a new technique where the structure surrounding the Ho ions is developed chemically prior to doping into the silica core. We have incorporated Ho3+ ions into various NPs, such as LaF3, Al2O3 and Lu2O3, to shield them from the silica glass matrix. Results indicate slightly longer lifetimes with Ho:LaF3 NPs and the possibility of further improvement with oxide NPs. We report the first of lasing in a Ho:Lu2O3 NP-doped fiber pumped at 1.95 μm and operating at 2.09 μm with a record slope efficiency of 85.2%.

  7. Anisotropic magnetocaloric effect in HoAlGa polycrystalline compound

    NASA Astrophysics Data System (ADS)

    Yan, Zhang; Xinqi, Zheng; JieFu, Xiong; Shulan, Zuo; Qiaoyan, Dong; Tongyun, Zhao; Baogen, Shen

    2018-05-01

    In this work, a nonnegligible anisotropic magnetocaloric effect (MCE) in HoAlGa polycrystalline compounds has been observed. With temperature increasing, the HoAlGa compound undergoes two kinds of magnetic transitions at 19 K and 31 K, respectively, the later has been recognized as an ordinary antiferromagnetic to paramagnetic (AFM-PM) transition. The -ΔS peak of HoAGa reaches 5.4 J/kg K and 1.5 J/kg K at 35 K along parallel and perpendicular texture directions respectively, for a field change of 0-5 T. The result indicates that the HoAlGa polycrystalline compounds with excellent anisotropic MCE can be expected to have effective magnetic refrigeration applications in low temperature range.

  8. OH, HO2, and HO2* Radical Chemistry During PROPHET-AMOS 2016: Measurements and Model Comparison

    NASA Astrophysics Data System (ADS)

    Bottorff, B.; Lew, M.; Rickly, P.; Stevens, P. S.

    2017-12-01

    The hydroxyl (OH) and peroxy radicals, both the hydroperoxy radical (HO2) and organic peroxy radicals (RO2), play an important role in atmospheric chemistry. In addition to controlling lifetimes of many trace gases important to issues of global climate change, reactions of these radicals can also lead to the production of ozone and secondary organic aerosols in the atmosphere. Previous measurements of these radicals in remote forest environments have shown serious discrepancies with modeled concentrations. These results bring into question our understanding of the atmospheric chemistry of isoprene and other biogenic VOCs under low NOX conditions. In the summer of 2016, OH, HO2 and HO2* (HO2 + αRO2) radicals were measured using the Indiana University Laser-Induced Fluorescence Fluorescence Assay by Gas Expansion (LIF-FAGE) technique as part of the Program for Research on Oxidants: PHtochemistry, Emissions, and Transport- Atmospheric Measurements of Oxidants in Summer (PROPHET-AMOS). This campaign took place in a forested area in northern Michigan characterized by high mixing ratios of isoprene and low mixing ratios of NOX. Ambient measurements from this campaign will be compared to previous measurements at this site and to modeled predictions using both the Regional Atmospheric Chemistry Mechanism (RACM2) and the Master Chemical Mechanism. Potential interferences associated with the OH measurements will also be examined.

  9. Non-coding RNA derived from the region adjacent to the human HO-1 E2 enhancer selectively regulates HO-1 gene induction by modulating Pol II binding

    PubMed Central

    Maruyama, Atsushi; Mimura, Junsei; Itoh, Ken

    2014-01-01

    Recent studies have disclosed the function of enhancer RNAs (eRNAs), which are long non-coding RNAs transcribed from gene enhancer regions, in transcriptional regulation. However, it remains unclear whether eRNAs are involved in the regulation of human heme oxygenase-1 gene (HO-1) induction. Here, we report that multiple nuclear-enriched eRNAs are transcribed from the regions adjacent to two human HO-1 enhancers (i.e. the distal E2 and proximal E1 enhancers), and some of these eRNAs are induced by the oxidative stress-causing reagent diethyl maleate (DEM). We demonstrated that the expression of one forward direction (5′ to 3′) eRNA transcribed from the human HO-1 E2 enhancer region (named human HO-1enhancer RNA E2-3; hereafter called eRNA E2-3) was induced by DEM in an NRF2-dependent manner in HeLa cells. Conversely, knockdown of BACH1, a repressor of HO-1 transcription, further increased DEM-inducible eRNA E2-3 transcription as well as HO-1 expression. In addition, we showed that knockdown of eRNA E2-3 selectively down-regulated DEM-induced HO-1 expression. Furthermore, eRNA E2-3 knockdown attenuated DEM-induced Pol II binding to the promoter and E2 enhancer regions of HO-1 without affecting NRF2 recruitment to the E2 enhancer. These findings indicate that eRNAE2-3 is functional and is required for HO-1 induction. PMID:25404134

  10. Heterogeneous Uptake of HO2 Radicals onto Submicron Atmospheric Aerosols

    NASA Astrophysics Data System (ADS)

    Matthews, P. S.; George, I. J.; Brooks, B.; Whalley, L. K.; Baeza-Romero, M. T.; Heard, D. E.

    2012-12-01

    OH and HO2 (HOx) radicals are closely coupled and OH is responsible for the majority of the oxidation in the troposphere and controls the concentrations of many trace species. Therefore, it is important to be able to accurately predict HOx concentrations. However, some field measurement studies have reported significantly lower HO2 radical concentrations than calculated by constrained box models using detailed chemical mechanisms. Although the inclusion of halogen chemistry into the mechanisms can explain much of the differences in the marine boundary layer (MBL) (1,2), HO2 uptake by aerosols has been suggested as a possible sink in the MBL (2), the Arctic troposphere (3) and the upper troposphere (4). There have been very few laboratory studies (5,6) on HO2 uptake by aerosols and the rates and mechanism is still uncertain. The HO2 uptake coefficients were measured for a variety of atmospherically relevant inorganic and organic aerosols. The measurements were performed using an aerosol flow tube combined with a Fluorescence Assay by Gas Expansion (FAGE) detector. The sensitive FAGE cell allowed low HO2 concentrations (108-109 molecule cm-3) to be injected into the flow tube using a moveable injector. By moving the injector along the flow tube, position dependent HO2 decays were able to be recorded which when plotted against the total aerosol surface area allowed an uptake coefficient to be obtained. The aerosols were generated using an atomiser or by homogeneous nucleation and the total aerosol surface area was measured using a Scanning Mobility Particle Sizer. The HO2 uptake coefficient (γ) was measured at room temperature for dry inorganic salts and dry organics (γ< 0.004), wet inorganic salts and wet organics (γ= 0.002-0.005), wet copper doped ammonium sulfate aerosols (γ= 0.28± 0.05) and ammonium sulfate aerosols doped with different molar amounts of iron (γ= 0.003-0.06). The pH dependence of the HO2 uptake coefficient was investigated, however no

  11. HoCaMA: Home Care Hybrid Multiagent Architecture

    NASA Astrophysics Data System (ADS)

    Fraile, Juan A.; Bajo, Javier; Abraham, Ajith; Corchado, Juan M.

    Home Care is one of the main objectives of Ambient Intelligence. Nowadays, the disabled and elderly population, which represents a significant part of our society, requires novel solutions for providing home care in an effective way. In this chapter, we present HoCaMA, a hybrid multiagent architecture that facilitates remote monitoring and care services for disabled patients at their homes. HoCaMA combines multiagent systems and Web services to facilitate the communication and integration with multiple health care systems. In addition, HoCaMA focuses on the design of reactive agents capable of interacting with different sensors present in the environment, and incorporates a system of alerts through SMS and MMS mobile technologies. Finally, it uses Radio Frequency IDentification and JavaCard technologies to provide advanced location and identification systems, as well as automatic access control facilities. HoCaMA has been implemented in a real environment and the results obtained are presented within this chapter.

  12. The effect of moderate-intensity exercise on the expression of HO-1 mRNA and activity of HO in cardiac and vascular smooth muscle of spontaneously hypertensive rats.

    PubMed

    Ren, Cailing; Qi, Jie; Li, Wanwei; Zhang, Jun

    2016-04-01

    The objective of this study was to observe the effects of moderate-intensity training on the activity of heme oxygenase (HO) and expression of HO-1 mRNA in the aorta and the cardiac muscle of spontaneously hypertensive rats (SHRs). After 9 weeks of swimming exercise, the activity of HO and expression of HO-1 mRNA in the SHRs were measured. The resting blood pressure in the exercise group was increased by 1.7% (P > 0.05), whereas it was significantly elevated by 10.3% (P < 0.01) in the SHR rats. Compared with animals in the control and sedentary groups, the expression level of HO-1 mRNA of aorta and cardiac muscle in the exercise group was significantly enhanced (P < 0.01). The HO activity and the content of plasma carbon monoxide (CO) in the sedentary group were dramatically decreased (P < 0.05 and P < 0.01, respectively) compared with the control group. HO activity and content of plasma CO in the exercise group were significantly higher compared with those in the sedentary group (P < 0.05 and P < 0.01, respectively). The HO/CO metabolic pathway might be involved in the regulation of blood pressure of the SHR models.

  13. Isolation of 163Ho from dysprosium target material by HPLC for neutrino mass measurements

    DOE PAGES

    Mocko, Veronika; Taylor, Wayne  A.; Nortier, Francois M.; ...

    2015-04-29

    The rare earth isotope 163Ho is of interest for neutrino mass measurements. This report describes the isolation of 163Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, 163Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm –3 α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized bymore » MC-ICP-MS to determine the 163Ho/ 165Ho ratio, 163Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4E5 for Dy. As a result, the isolated Ho fraction contained 24.8 ±1.3 ng of 163Ho corresponding to holmium recovery of 72 ± 3%.« less

  14. Isolation of 163Ho from dysprosium target material by HPLC for neutrino mass measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mocko, Veronika; Taylor, Wayne  A.; Nortier, Francois M.

    The rare earth isotope 163Ho is of interest for neutrino mass measurements. This report describes the isolation of 163Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, 163Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm –3 α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized bymore » MC-ICP-MS to determine the 163Ho/ 165Ho ratio, 163Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4E5 for Dy. As a result, the isolated Ho fraction contained 24.8 ±1.3 ng of 163Ho corresponding to holmium recovery of 72 ± 3%.« less

  15. A Reevaluation of Airborne HO(x) Observations from NASA Field Campaigns

    NASA Technical Reports Server (NTRS)

    Olson, Jennifer; Crawford, James H.; Chen, Gao; Brune, William H.; Faloona, Ian C.; Tan, David; Harder, Hartwig; Martinez, Monica

    2006-01-01

    In-situ observations of tropospheric HO(x) (OH and HO2) obtained during four NASA airborne campaigns (SUCCESS, SONEX, PEM-Tropics B and TRACE-P) are reevaluated using the NASA Langley time-dependent photochemical box model. Special attention is given to previously diagnosed discrepancies between observed and predicted HO2 which increase with higher NO(x) levels and at high solar zenith angles. This analysis shows that much of the model discrepancy at high NO(x) during SUCCESS can be attributed to modeling observations at time-scales too long to capture the nonlinearity of HO(x) chemistry under highly variable conditions for NO(x). Discrepancies at high NO(x) during SONEX can be moderated to a large extent by complete use of all available precursor observations. Differences in kinetic rate coefficients and photolysis frequencies available for previous studies versus current recommendations also explain some of the disparity. Each of these causes is shown to exert greater influence with increasing NO(x) due to both the chemical nonlinearity between HO(x) and NO(x) and the increased sensitivity of HO(x) to changes in sources at high NO(x). In contrast, discrepancies at high solar zenith angles will persist until an adequate nighttime source of HO(x) can be identified. It is important to note that this analysis falls short of fully eliminating the issue of discrepancies between observed and predicted HO(x) for high NO(x) environments. These discrepancies are not resolved with the above causes in other data sets from ground-based field studies. Nevertheless, these results highlight important considerations in the application of box models to observationally based predictions of HO(x) radicals.

  16. Low temperature specific heat of frustrated antiferromagnet HoInCu4

    NASA Astrophysics Data System (ADS)

    Weickert, Franziska; Fritsch, Veronika; Bambaugh, Ryan; Sarrao, John; Thompson, Joe D.; Movshovich, Roman

    2014-03-01

    We present low temperature specific heat measurements of single crystal HoInCu4, down to 35 mK and in magnetic field up to 12 Tesla. Ho atoms are arranged in an FCC lattice of the edge-sharing tetrahedra, and undergo an antiferromagnetic ordering at TN = 0.76 K, with the frustration parameter f = -ΘCW /TN of 14.3. Magnetic AF order is suppressed in field H0 ~ 4 T. The low temperature Schottky anomaly due to Ho evolves smoothly as a function of field through H0 and TN. The peak value of the anomaly remains roughly constant from 0 T to 12 T. The temperature of the anomaly's peak remains constant at TSch ~ 170 mK for HHo spins in zero field as well as an increasing moment on Ho once the AF order is suppressed. The measured entropy of HoInCu4 at 12 T and 2K is 17.32 J/mol-K ~ Rln8 expected for an I =7/2 nuclear spin of Ho. Work at LANL was performed under the auspices of the US DOE, OBES, MSE division.

  17. Kinetics of the reaction of HO2 with ozone

    NASA Astrophysics Data System (ADS)

    Zahniser, Mark S.; Howard, Carleton J.

    1980-08-01

    Rate constants were measured for the reaction HO2+O3→OH+2O2(k1) using a discharge-flow system with laser magnetic resonance detection of both HO2 and OH. k1 was determined directly from the first order decay of HO2 in excess O3 when C2F3Cl was added to scavenge the OH product and prevent interference from the faster reaction OH+O3→HO2+O2(k2). The ratio k2/k1 was independently determined from the steady-state [HO2]/[OH] ratio obtained without C2F3Cl. Results from the scavenger method are given by k1= (1.4±0.4)×10-14 exp [-(580±100)/T] cm3 s-1 for 245 K

  18. Measurements of HO2 chemical kinetics with a new detection method

    NASA Technical Reports Server (NTRS)

    Lee, L. C.; Suto, M.

    1986-01-01

    Research for the period from December 1, 1985 to May 31, 1986 is discussed, i.e., the reaction rate constant of HO2+O3 has been measured with a discharge-flow-tube apparatus. The HO2 radical was detected by the OH(A-X) photofragment emission produced from photodissociative excitation of HO2 at 147 nm. In the meantime, the optical emissions produced by the vacuum ultraviolet excitation of chemical species in the flow tube were investigated and used to examine the possibility for their interference with the HO2 detection. The research results are summarized below.

  19. High-pulse-energy 3.9-μm lasers in Ho:BYF

    NASA Astrophysics Data System (ADS)

    Stutz, Russell; Miller, Harold C.; Dinndorf, Kenneth M.; Cassanho, Arlete; Jenssen, Hans P.

    2004-07-01

    Experimental results describing pulsed lasers operating near 3.9 μm on the Ho3+ (5I5-5I6) transition in highly-doped (> 10 at. %) barium yttrium fluoride (BaY2F8 or BYF) will be presented. The 5I5 manifolds in Ho:BYF were pumped using a flashlamp excited, free-running Cr:LiSAF laser tuned to the Ho3+ absorption peak near 889nm. Ho3+ concentrations of 10%, 20%, 30% and 40% in BYF were lased in a simple end-pumped resonator. Some similar data was also obtained in 10% and 20% Ho:YLF. The highest 3.9 μm pulse energy obtained in the comparative study was 55 mJ (at ~10% optical-to-optical efficiency) using the 30% Ho:BYF crystal. A dual end-pumped laser in 30% Ho:BYF was also demonstrated, providing a pulse energy of 90 mJ in a near diffraction limited beam (M2 ~ 1.2). Emission decay data was taken to shed light on the observed dependence of laser efficiency on holmium concentration and excitation density. The lifetimes of both lasing levels (5I5 and 5I6) deviate rather significantly from their low-concentration values. Plausible energy transfer processes that may be responsible for the observed trends in the laser and emission data will also be discussed.

  20. Operation of Ho:YAG ultrafast laser inscribed waveguide lasers.

    PubMed

    McDaniel, Sean; Thorburn, Fiona; Lancaster, Adam; Stites, Ronald; Cook, Gary; Kar, Ajoy

    2017-04-20

    We report fabrication and operation of multi-watt level waveguide lasers utilizing holmium-doped yttrium aluminum garnet (Ho:YAG). The waveguides were fabricated using ultrafast laser inscription, which relies on a chirped pulse ytterbium fiber laser to create depressed cladding structures inside the material. A variety of waveguides were created inside the Ho:YAG samples. We demonstrate output powers of ∼2  W from both a single-mode 50 μm waveguide laser and a multimode 80 μm waveguide laser. In addition, laser action from a co-doped Yb:Ho:YAG sample under in-band pumping conditions was demonstrated.

  1. Review of Tm and Ho Materials; Spectroscopy and Lasers

    NASA Technical Reports Server (NTRS)

    Walsh, Brian M.

    2008-01-01

    A review of Tm and Ho materials is presented, covering some fundamental aspects on the spectroscopy and laser dynamics in both single and co-doped systems. Following an introduction to 2- m lasers, applications and historical development, the physics of quasi-four level lasers, energy transfer and modeling are discussed in some detail. Recent developments in using Tm lasers to pump Ho lasers are discussed, and seen to offer some advantages over conventional Tm:Ho lasers. This article is not intended as a complete review, but as a primer for introducing concepts and a resource for further study.

  2. FAGE measurements of tropospheric HO with measurements and model of interferences

    NASA Technical Reports Server (NTRS)

    Hard, T. M.; Mehrabzadeh, A. A.; Chan, C. Y.; O'Brien, R. J.

    1992-01-01

    Ambient HO measurements by low-pressure laser-excited fluorescence with chemical modulation, and supporting ozone and water-vapor data, are presented for periods in May and August 1987. The observed peak daytime ambient HO concentrations are in the range (2.5 to 8) x 10 exp 6 molecules/cu cm and show small negative offsets due to photochemical interference. Direct measurements of the interference at fixed (O3) give the dependence on ambient (H2O) and on the modulating reagent (isobutane). At ambient (O3) = 30 ppb and 10 torr H2O, with excitation and detection at a total pressure of 4 torr, the net interference is equal to (HO) = -1.3 x 10 exp 6 molecules/cu cm. Production of HO by the reaction of isobutane with O(1D) accounts for the negative interference. Quenching of HO fluorescence by the modulating reagent contributes a smaller positive term to the interference; kinetic measurements of the quenching rate coefficient are reported. The experimental interference results are compared with a detailed kinetic model of HO production, excitation, relaxation, and detection; reasonable agreement is found.

  3. 61. Upper panel in cornerpower panel lcpa lower panel in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. Upper panel in corner-power panel lcpa lower panel in corner-oxygen regeneration unit, at right-air conditioner control panel, on floor-bio-pack 45 for emergency breathing, looking northwest - Ellsworth Air Force Base, Delta Flight, Launch Control Facility, County Road CS23A, North of Exit 127, Interior, Jackson County, SD

  4. Reflected shock tube studies of high-temperature rate constants for OH + NO2 --> HO2 + NO and OH + HO2 --> H2O + O2.

    PubMed

    Srinivasan, Nanda K; Su, Meng-Chih; Sutherland, James W; Michael, Joe V; Ruscic, Branko

    2006-06-01

    The motivation for the present study comes from the preceding paper where it is suggested that accepted rate constants for OH + NO2 --> NO + HO2 are high by approximately 2. This conclusion was based on a reevaluation of heats of formation for HO2, OH, NO, and NO2 using the Active Thermochemical Table (ATcT) approach. The present experiments were performed in C2H5I/NO2 mixtures, using the reflected shock tube technique and OH-radical electronic absorption detection (at 308 nm) and using a multipass optical system. Time-dependent profile decays were fitted with a 23-step mechanism, but only OH + NO2, OH + HO2, both HO2 and NO2 dissociations, and the atom molecule reactions, O + NO2 and O + C2H4, contributed to the decay profile. Since all of the reactions except the first two are known with good accuracy, the profiles were fitted by varying only OH + NO2 and OH + HO2. The new ATcT approach was used to evaluate equilibrium constants so that back reactions were accurately taken into account. The combined rate constant from the present work and earlier work by Glaenzer and Troe (GT) is k(OH+NO2) = 2.25 x 10(-11) exp(-3831 K/T) cm3 molecule(-1) s(-1), which is a factor of 2 lower than the extrapolated direct value from Howard but agrees well with NO + HO2 --> OH + NO2 transformed with the updated equilibrium constants. Also, the rate constant for OH + HO2 suitable for combustion modeling applications over the T range (1200-1700 K) is (5 +/- 3) x 10(-11) cm3 molecule(-1) s(-1). Finally, simulating previous experimental results of GT using our updated mechanism, we suggest a constant rate for k(HO2+NO2) = (2.2 +/- 0.7) x 10(-11) cm3 molecule(-1) s(-1) over the T range 1350-1760 K.

  5. Inhibition of the NADPH oxidase regulates HO-1 expression in chronic myeloid leukemia

    PubMed Central

    Singh, Melissa M.; Irwin, Mary E.; Gao, Yin; Ban, Kechen; Shi, Ping; Arlinghaus, Ralph B.; Amin, Hesham M.; Chandra, Joya

    2011-01-01

    Background Patients with blast crisis phase chronic myelogeneous leukemia (CML) have poor response to tyrosine kinase inhibitors designed to inhibit the BCR-ABL1 oncogene. Recent work has shown that heme oxygenase 1 (HO-1) expression is increased in BCR-ABL1 expressing cells and that inhibition of HO-1 in CML leads to reduced cellular growth suggesting HO-1 may be a plausible target for therapy. Here we sought to clarify the mechanism of HO-1 overexpression and the role of the NADPH oxidase as a contributor to this mechanism in CML. Methods HO-1 expression was evaluated in CML bone marrow specimens from patients in various stages of disease, in a transplant based model for CML and in CML cell lines. Chemical and genetic inhibition of the NADPH oxidase was carried out in CML cells. Results Blast crisis CML patient specimens displayed higher levels of HO-1 staining than chronic or accelerated phase. HO-1 upregulation in BCR-ABL1 expressing cells was suppressed by diphenyliodonium (DPI), a chemical inhibitor of the NADPH oxidase. Targeting the NADPH oxidase through RNAi to Rac1, a dominant negative Rac1 construct or an inhibitor of Rac1 activity also blunted HO-1 protein expression. Moreover, inhibition of the NADPH oxidase by RNAi directed towards p47phox similarly abrogated HO-1 levels. Conclusion BCR-ABL1 expression upregulates HO-1, a survival factor for CML cells. This upregulation is more pronounced in blast crisis CML relative to early stage disease and is mediated by the NADPH oxidase components Rac1 and p47phox. Expression of p47phox is increased in BCR-ABL1 expressing cells. PMID:22139798

  6. Mid-infrared lasing from Ho(3+) in bulk InF(3) glass.

    PubMed

    Berrou, Antoine; Kieleck, Christelle; Eichhorn, Marc

    2015-04-15

    We report on an Ho3+:InF3 glass laser pumped by a Cr3+:LiSAF laser emitting at 889 nm. Ho3+:InF3 glass is a promising material for direct mid-infrared lasers around 4 μm. To evaluate the performances of this new material, we compared it to an Ho3+:BYF crystalline laser pumped by the same source. At 650 mJ pump energy, 7.2 mJ (46 mJ) was obtained with Ho3+:InF3 (Ho3+:BYF), respectively. This is, to the best of our knowledge, the first reported laser activity in this type of glass.

  7. HO-CHUNK: Radiation Transfer code

    NASA Astrophysics Data System (ADS)

    Whitney, Barbara A.; Wood, Kenneth; Bjorkman, J. E.; Cohen, Martin; Wolff, Michael J.

    2017-11-01

    HO-CHUNK calculates radiative equilibrium temperature solution, thermal and PAH/vsg emission, scattering and polarization in protostellar geometries. It is useful for computing spectral energy distributions (SEDs), polarization spectra, and images.

  8. Critical Slowing Down in Zn-Mg-Ho Quasicrystal

    NASA Astrophysics Data System (ADS)

    Sugiyama, Jun; Nozaki, Hiroshi; Ansaldo, Eduardo J.; Morris, Gerald D.; Brewer, Jess H.; Sato, Taku J.

    By means of longitudinal field muon-spin spectroscopy, we have found a clear critical slowing down caused by spin fluctuation of Ho moments in the icosahedral quasicrystal (QC), i-ZnMgHo, with freezing temperature (Tf =1.95 K), for which the susceptibility showed an anomaly at5K. The difference is attributed to crystalline elec-tric field (CEF) effects. The muons experience a broad, fluctuating, field distribution, of width Δ ∼6.3Taround Tf . The effect of the CEF is also apparent in zero field and weak applied transverse field measurements, with an onset around 60 K. For the Cd-based QCs (CdMgHo and CdMgGd), which exhibited two freezing temperatures in the susceptibility, the change in fluctuation rate, i.e. freezing, occurs at the lower Tf .

  9. Heme oxygenase-1 (HO-1) inhibits postmyocardial infarct remodeling and restores ventricular function.

    PubMed

    Liu, Xiaoli; Pachori, Alok S; Ward, Christopher A; Davis, J Paul; Gnecchi, Massimiliano; Kong, Deling; Zhang, Lunan; Murduck, Jared; Yet, Shaw-Fang; Perrella, Mark A; Pratt, Richard E; Dzau, Victor J; Melo, Luis G

    2006-02-01

    We reported previously that predelivery of the anti-oxidant gene heme oxygenase-1 (HO-1) to the heart by adeno associated virus (AAV) markedly reduces injury after acute myocardial infarction (MI). However, the effect of HO-1 gene delivery on postinfarction recovery has not been investigated. In the current study, we assessed the effect of HO-1 gene delivery on post-MI left ventricle (LV) remodeling and function using echocardiographic imaging and histomorphometric approaches. Two groups of Sprague-Dawley rats were injected with 4 x 10(11) particles of AAV-LacZ (control) or AAV-hHO-1 in the LV wall. Eight wk after gene transfer, the animals were subjected to 30 min of ischemia by ligation of left anterior descending artery (LAD) followed by reperfusion. Echocardiographic measurements were obtained in a blinded fashion prior and at 1.5 and 3 months after I/R. Ejection fraction (EF) was reduced by 13% and 40% in the HO-1 and LacZ groups, respectively at 1.5 months after MI. Three months after MI, EF recovered fully in the HO-1, but only partially in the LacZ-treated animals. Post-MI LV dimensions were markedly increased and the anterior wall was markedly thinned in the LacZ-treated animals compared with the HO-1-treated animals. Significant myocardial scarring and fibrosis were observed in the LacZ-group in association with elevated levels of interstitial collagen I and III and MMP-2 activity. Post-MI myofibroblast accumulation was reduced in the HO-1-treated animals, and retroviral overexpression of HO-1 reduced proliferation of isolated cardiac fibroblasts. Our data indicate that rAAV-HO-1 gene transfer markedly reduces fibrosis and ventricular remodeling and restores LV function and chamber dimensions after myocardial infarction.

  10. Paracrine action of HO-1-modified mesenchymal stem cells mediates cardiac protection and functional improvement.

    PubMed

    Zeng, Bin; Ren, Xiaofeng; Lin, Guosheng; Zhu, Chengang; Chen, Honglei; Yin, Jiechao; Jiang, Hong; Yang, Bo; Ding, Danhua

    2008-10-01

    The aim has been to determine whether the supernatants of mesenchymal stem cells (MSCs) transfected with adenovirus carrying human heme oxygenase-1 (hHO-1) gene protect cardiomyocytes from ischemic injury. We have found that hHO-1 infected MSCs (hHO-1-MSCs) increased expression of hHO-1 protein. Apoptosis of cultured hHO-1-MSCs exposed to hypoxia was suppressed. Several cytokines, including HGF, bFGF, TGF-beta, VEGF and IL-1beta, were produced by hHO-1-MSCs, some being significantly enhanced under hypoxia stimulation. Meanwhile, those cytokines reduced caspase-3 level and activity in cultured adult rat ventricular cardiomyocytes (ARVCs) exposed to hypoxia. Supernatants obtained from hHO-1-MSCs improved left ventricular function, limited myocardial infarct size, increased microvessel density, and inhibited apoptosis of cardiomyocytes in rat myocardial infarction. It can be concluded hHO-1-modified MSCs prevent myocardial cell injury via secretion of paracrine-acting mediators.

  11. HO(x) Measurements in PEM Tropics B with the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS)

    NASA Technical Reports Server (NTRS)

    Brune, William H.

    2001-01-01

    The primary objective of PEM Tropics B was to study the processes responsible for the production and loss of tropospheric ozone over the tropical Pacific. This region of the globe contains very clean air as well as aged, polluted air that was advected from both the Asian and American continents. Understanding ozone requires understanding of HO(x) (HO(x) = OH + HO2) chemistry, since the reaction between H02 and NO leads to ozone production and the production of OH often requires ozone loss. In addition, OH is the atmosphere's primary oxidant. Since most atmospheric oxidation is thought to occur in the tropical lower troposphere, measurements during PEM Tropics B should provide an important test of the OH abundances and distributions. Thus, understanding and thoroughly testing HO(x) processes was an important objective of PEM Tropics B. Several issues need to be tested, One is HO, production rates and sources, since HO,, production directly affects ozone production and loss. Another is HO(x) behavior in and around clouds, since HO(x) is lost to cloud particles, but convection may bring HO(x) precursors from near the surface to the upper troposphere. A third is the rise and fall of HO(x) at sunrise and sunset, since these variations give strong indications of the important sources and sinks of HO(x). Making and interpreting high-quality OH and H02 measurements from the NASA DC-8 during PEM Tropics B is the objective of this research effort.

  12. [hHO-1 structure prediction and its mutant construct, expression, purification and activity analysis].

    PubMed

    Xia, Zhen Wei; Cui, Wen Jun; Zhou, Wen Pu; Zhang, Xue Hong; Shen, Qing Xiang; Li, Yun Zhu; Yu, Shan Chang

    2004-10-01

    Human Heme Oxygenase-1 (hHO-1) is the rate-limiting enzyme in the catabolism reaction of heme, which directly regulates the concentration of bilirubin in human body. The mutant structure was simulated by Swiss-pdbviewer procedure, which showed that the structure of active pocket was changed distinctly after Ala25 substituted for His25 in active domain, but the mutated enzyme still binded with heme. On the basis of the results, the expression vectors, pBHO-1 and pBHO-1(M), were constructed, induced by IPTG and expressed in E. coli DH5alpha strain. The expression products were purified with 30%-60% saturation (NH4)2SO4 and Q-Sepharose Fast Flow column chromatography. The concentration of hHO-1 in 30%-60% saturation (NH4)2SO4 components and in fractions through twice column chromatography was 3.6-fold and 30-fold higher than that in initial product, respectively. The activity of wild hHO-1 (whHO-1) and mutant hHO-1 (deltahHO-1) showed that the activity of deltahHO-1 was reduced 91.21% compared with that of whHO-1. The study shows that His25 is of importance for the mechanism of hHO-1, and provides the possibility for effectively regulating the activity to exert biological function.

  13. Fer-Ho Anaphora in Catalan: Semantic and Discourse Properties

    ERIC Educational Resources Information Center

    Busquets, Joan

    2018-01-01

    This paper considers the anaphoric status of the pro-form "fer-ho" (do it) in Catalan [This paper contains some ideas included in Busquets (2005)]. I discuss some anaphoric properties of "fer-ho" as deep anaphora. I also compare these properties to those of other types of anaphora, like VPE and pseudogapping (pg). I show that…

  14. Single-frequency gain-switched Ho-doped fiber laser

    NASA Astrophysics Data System (ADS)

    Geng, Jihong; Wang, Q.; Luo, T.; Case, B.; Jiang, S.; Amzajerdian, Farzin; Yu, Jirong

    2012-10-01

    We demonstrate a single-frequency gain-switched Ho-doped fiber laser based on heavily doped silicate glass fiber fabricated in house. A Q-switched Tm-doped fiber laser at 1.95μm was used to gain-switch the Ho-doped fiber laser via in-band pumping. Output power of the single-frequency gain-switched pulses has been amplified in a cladding-pumped Tm-Ho-codoped fiber amplifier with 1.2m active fiber pumped at 803nm. Two different nonlinear effects, i.e., modulation instability and stimulated Brillouin scattering, could be seen in the 10μm-core fiber amplifier when the peak power exceeds 3kW. The single-frequency gain-switched fiber laser was operated at 2.05μm, a popular laser wavelength for Doppler lidar application. This is the first demonstration of this kind of fiber laser.

  15. Flashlamp-pumped Ho:Tm:Cr:LuAG laser

    NASA Technical Reports Server (NTRS)

    Jani, Mahendra G. (Inventor); Barnes, Norman P. (Inventor); Murray, Keith E. (Inventor); Kokta, Milan R. (Inventor)

    1997-01-01

    A room temperature solid-state laser is provided. A laser crystal is disposed in a laser cavity. The laser crystal has a LuAG host material doped with a concentration of about 0.35% Ho ions, about 5.57% Tm ions and at least about 1.01% Cr ions. A broadband energizing source such as a flashlamp is disposed transversely to the laser crystal to energize the Ho ions, Tm ions and Cr ions.

  16. 1.88 Micrometers InGaAsP Pumped, Room Temperature Ho: LuAG Laser

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.; Amzajerdian, Farzin; Reichle, Donald J.; Busch, George; Leisher, Paul

    2009-01-01

    A room temperature, directly diode pumped Ho:LuAG laser oscillated for the first time. Direct pumping of the Ho upper laser manifold maximizes efficiency, minimizes heating, and eliminates Ho:Tm energy sharing. Design and performance are presented.

  17. Production, Quality Control and Biological Evaluation of 166Ho-PDTMP as a Possible Bone Palliation Agent

    PubMed Central

    Zolghadri, Samaneh; Jalilian, Amir Reza; Naseri, Zohreh; Yousefnia, Hassan; Bahrami-Samani, Ali; Ghannadi-Maragheh, Mohammad; Afarideh, Hossein

    2013-01-01

    Objective(s): In this study, 166Ho-1,2-propylene di-amino tetra(methy1enephosphonicAcid) (166Ho-PDTMP) complex was prepared as a bone palliation agent. Materials and Methods: The complex was successfully prepared using an in-house synthesized EDTMP ligand and 166HoCl3. Ho-166 chloride was obtained by thermal neutron irradiation (1 × 1013 n.cm-2.s-1) of natural Ho(NO3)3 samples followed by radiolabeling and stability studies. Biodistribution in wild type rats was also peformed. Results: The complex was prepared with the specific activity of 278 GBq/mg and high radiochemical purity (>99%, checked by ITLC). 166Ho-PDTMP complex was stabilized in the final preparation and in the presence of human serum (>90%) up to 72 hr. The biodistribution of 166Ho-PDTMP in wild-type rats demonstrated significant bone uptake was up to 48 hr compared to 166HoCl3. Conclusion: The produced 166Ho-PDTMP properties suggest a possible new bone palliative therapeutic to overcome the metastatic bone pains. PMID:23826495

  18. Growth and anisotropic thermal properties of biaxial Ho:YAlO3 crystal

    NASA Astrophysics Data System (ADS)

    Dong, Qin; Zhao, Guangjun; Chen, Jianyu; Ding, Yuchong; Zhao, Chengchun

    2010-07-01

    Ho:YAlO3 (YAP) crystal with large size and good optical quality has been grown by the Czochralski method. Thermal properties of the as-grown Ho:YAP crystal have been investigated by measuring the temperature-dependent, anisotropic thermal expansion, specific heat, thermal diffusion, and thermal conductivity. The results show that Ho:YAP crystal possesses a large anisotropic thermal expansion and good thermal conductivity. The calculated average thermal expansion coefficients along a, b, and c axis are αa=9.18×10-6/K, αb=1.94×10-6/K, and αc=7.61×10-6/K from 293.15 to 770.15 K. The thermal conductivities along a, b, and c axis are up to 11.6, 9.9, and 12.3 W m-1 K-1 at 298.15 K. Compared with Ho: Y3Al5O12 (YAG), Ho:YAP crystal has a larger thermal conductivity along a axis from 298.15 to 568.15 K.

  19. Injection-seeded operation of a Q-switched Cr,Tm,Ho:YAG laser

    NASA Technical Reports Server (NTRS)

    Henderson, Sammy W.; Hale, Charley P.; Magee, James R.

    1991-01-01

    Single-frequency Tm,Ho:YAG lasers operating near 2 microns are attractive sources for several applications including eye-safe laser radar (lidar) and pumping of AgGaSe2 parametric oscillators for efficient generation of longer wavelengths. As part of a program to develop a coherent lidar system using Tm,Ho:YAG lasers, a diode laser-pumped tunable CW single-longitudinal-mode (SLM) Cr:Tm:Ho:YAG laser and a flashlamp-pumped single-transverse-mode Q-switched Cr,Tm,Ho:YAG laser were developed. The CW laser was used to injection-seed the flashlamp-pumped laser, resulting in SLM Q-switched output. Operational characteristics of the CW and Q-switched lasers and injection-seeding results are reported.

  20. A new measurement of the half-life of (166m)Ho.

    PubMed

    Nedjadi, Y; Bailat, C; Caffari, Y; Froidevaux, P; Wastiel, C; Kivel, N; Guenther-Leopold, I; Triscone, G; Jaquenod, F; Bochud, F

    2012-09-01

    The work presented here is a new and precise measurement of the half-life of (166m)Ho by determining the activity concentration, using an ionisation chamber calibrated for this nuclide, and measuring the number of (166m)Ho atoms using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). Since the isotope (166)Er interferes with the mass spectrometric measurement, Er has to be eliminated from the (166m)Ho radioactive solution. The elimination was achieved using ion-exchange chromatography with the cation exchange resin Dowex AG 50W-X8 and 2-Hydroxybutanoic acid as the mobile phase. After a first transit through the chromatographic column, the purified (166m)Ho eluate was spiked with natural Er to get a resulting Er isotopic composition close to that of natural Er at better than 99.5%, and then it underwent two further separations to eliminate the Er. The activity concentration of this Er-free radioactive (166m)Ho solution was measured in our reference ionisation chamber calibrated for this nuclide by means of the 4πβ(PC)-γ and 4πβ(PS)-4πγ coincidence techniques and integral counting with a well-type NaI(Tl) detector and Monte Carlo efficiencies. An aliquot of this standardized solution was sent to the Paul Scherrer Institute (PSI) for mass concentration determination using an isotope dilution MC-ICP-MS approach. The mass concentration of (166m)Ho in this solution was determined with 0.25% relative standard uncertainty. This value was corroborated by two other independent measurements. The new half-life of (166m)Ho, 1132.6(39) years (k=1), is compatible with the value determined in 1965, but is 5.6% shorter and about 43 times more precise. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. HoPaCI-DB: host-Pseudomonas and Coxiella interaction database

    PubMed Central

    Bleves, Sophie; Dunger, Irmtraud; Walter, Mathias C.; Frangoulidis, Dimitrios; Kastenmüller, Gabi; Voulhoux, Romé; Ruepp, Andreas

    2014-01-01

    Bacterial infectious diseases are the result of multifactorial processes affected by the interplay between virulence factors and host targets. The host-Pseudomonas and Coxiella interaction database (HoPaCI-DB) is a publicly available manually curated integrative database (http://mips.helmholtz-muenchen.de/HoPaCI/) of host–pathogen interaction data from Pseudomonas aeruginosa and Coxiella burnetii. The resource provides structured information on 3585 experimentally validated interactions between molecules, bioprocesses and cellular structures extracted from the scientific literature. Systematic annotation and interactive graphical representation of disease networks make HoPaCI-DB a versatile knowledge base for biologists and network biology approaches. PMID:24137008

  2. GEC-targeted HO-1 expression reduces proteinuria in glomerular immune injury.

    PubMed

    Duann, Pu; Lianos, Elias A

    2009-09-01

    Induction of heme oxygenase (HO)-1 is a key defense mechanism against oxidative stress. Compared with tubules, glomeruli are refractory to HO-1 upregulation in response to injury. This can be a disadvantage as it may be associated with insufficient production of cytoprotective heme-degradation metabolites. We, therefore, explored whether 1) targeted HO-1 expression can be achieved in glomeruli without altering their physiological integrity and 2) this expression reduces proteinuria in immune injury induced by an anti-glomerular basement membrane (GBM) antibody (Ab). We employed a 4.125-kb fragment of a mouse nephrin promoter downstream to which a FLAG-tagged hHO-1 cDNA sequence was inserted and subsequently generated transgenic mice from the FVB/N parental strain. There was a 16-fold higher transgene expression in the kidney than nonspecific background (liver) while the transprotein immunolocalized in glomerular epithelial cells (GEC). There was no change in urinary protein excretion, indicating that GEC-targeted HO-1 expression had no effect on glomerular protein permeability. Urinary protein excretion in transgenic mice with anti-GBM Ab injury (days 3 and 6) was significantly lower compared with wild-type controls. There was no significant change in renal expression levels of profibrotic (TGF-beta1) or anti-inflammatory (IL-10) cytokines in transgenic mice with anti-GBM Ab injury. These observations indicate that GEC-targeted HO-1 expression does not alter glomerular physiological integrity and reduces proteinuria in glomerular immune injury.

  3. GEC-targeted HO-1 expression reduces proteinuria in glomerular immune injury

    PubMed Central

    Duann, Pu; Lianos, Elias A.

    2009-01-01

    Induction of heme oxygenase (HO)-1 is a key defense mechanism against oxidative stress. Compared with tubules, glomeruli are refractory to HO-1 upregulation in response to injury. This can be a disadvantage as it may be associated with insufficient production of cytoprotective heme-degradation metabolites. We, therefore, explored whether 1) targeted HO-1 expression can be achieved in glomeruli without altering their physiological integrity and 2) this expression reduces proteinuria in immune injury induced by an anti-glomerular basement membrane (GBM) antibody (Ab). We employed a 4.125-kb fragment of a mouse nephrin promoter downstream to which a FLAG-tagged hHO-1 cDNA sequence was inserted and subsequently generated transgenic mice from the FVB/N parental strain. There was a 16-fold higher transgene expression in the kidney than nonspecific background (liver) while the transprotein immunolocalized in glomerular epithelial cells (GEC). There was no change in urinary protein excretion, indicating that GEC-targeted HO-1 expression had no effect on glomerular protein permeability. Urinary protein excretion in transgenic mice with anti-GBM Ab injury (days 3 and 6) was significantly lower compared with wild-type controls. There was no significant change in renal expression levels of profibrotic (TGF-β1) or anti-inflammatory (IL-10) cytokines in transgenic mice with anti-GBM Ab injury. These observations indicate that GEC-targeted HO-1 expression does not alter glomerular physiological integrity and reduces proteinuria in glomerular immune injury. PMID:19587144

  4. Preliminary dosimetric evaluation of (166)Ho-TTHMP for human based on biodistribution data in rats.

    PubMed

    Yousefnia, Hassan; Zolghadri, Samaneh; Jalilian, Amir Reza; Tajik, Mojtaba; Ghannadi-Maragheh, Mohammad

    2014-12-01

    In this work, the absorbed dose to each organ of human for (166)Ho-TTHMP was evaluated based on biodistribution studies in rats by a RADAR method and was compared with (166)Ho-DOTMP as the only clinically used Ho-166 bone marrow ablative agent. The highest absorbed dose for this complex is observed in red marrow with 0.922mGy/MBq. The results show that (166)Ho-TTHMP has considerable characteristics compared to (166)Ho-DOTMP and can be a good candidate for bone marrow ablation in patients with multiple myeloma. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Predicting lanthanide cluster properties: a comparison with the observed optical spectra of HO 2

    NASA Astrophysics Data System (ADS)

    Nemukhin, A. V.; Ermilov, A. Yu.; Petrukhina, M. A.; Klotzbücher, W. E.; Smets, J.

    1997-10-01

    Ab initio pseudopotential calculations for HO and HO 2 have been carried out in order to support an assignment of the bands observed in UV-visible spectra of matrix isolated holmium species. SCF, MCSCF and configuration interaction (CI) procedures have been used with quasirelativistic pseudopotentials to compute the ground and excited state energies of HO and HO 2, together with the dipole transition moments. For HO 2, using a Q = 11 pseudopotential (describing the holmium atom in the 4f 106s 25d 1 electronic state), two transitions from the ground state σg2σu2πu2 to the states with principal excitations σu → πg and π u → σ g∗ are predicted at 499 and 524 nm. These two lines, with predicted close intensities, correlate nicely with the observed features at 498/504 and 558/563nm in the spectrum of matrix-isolated HO 2.

  6. Optical transitions of Ho(3+) in oxyfluoride glasses and upconversion luminescence of Ho(3+)/Yb(3+)-codoped oxyfluoride glasses.

    PubMed

    Feng, Li; Wu, Yinsu

    2015-05-05

    Optical properties of Ho(3+)-doped SiO2-BaF2-ZnF2 glasses have been investigated on the basis of the Judd-Ofelt theory. Judd-Ofelt intensity parameters, radiative transition probabilities, fluorescence branching ratios and radiative lifetimes have been calculated for different glass compositions. Upconversion emissions were observed in Ho(3+)/Yb(3+)-codoped SiO2-BaF2-ZnF2 glasses under 980nm excitation. The effects of composition, concentration of the doping ions, and excitation pump power on the upconversion emissions were also systematically studied. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. [Homozygous familial hypercholesterolaemia: Spanish adaptation of the position paper from the Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society. Consensus document of the Spanish Society of Arteriosclerosis (SEA) and Familial Hypercholesterolaemia Foundation (FHF)].

    PubMed

    Ascaso, Juan F; Mata, Pedro; Arbona, Cristina; Civeira, Fernando; Valdivielso, Pedro; Masana, Luis

    2015-01-01

    Homozygous familial hypercholesterolaemia (HoFH) is a rare life-threatening disease characterized by markedly elevated circulating levels of low-density lipoprotein cholesterol (LDL-C) and accelerated, premature atherosclerotic cardiovascular disease (ACVD). The Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society (EAS) has recently published a clinical guide to diagnose and manage HoFH (Eur Heart J. 2014;35:2146-57). Both the Spanish Society of Atherosclerosis (SEA) and Familial Hypercholesterolaemia Foundation (FHF) consider this European Consensus document of great value and utility. However, there are particularities in our country which advise to have a Spanish adaptation of the European HoFH document in order to approximate this clinical guide to our environment. In Spain, chronic treatment with statins, ezetimibe and resins (colesevelam) has a reduced contribution in the National Health System (NHS) and is one of the few European countries where LDL apheresis is included in the Basic Service Portfolio coverage. This Spanish document also includes clinical experience in the management of these patients in our country. The Drafting Committee emphasizes the need for early identification of HoFH patients, prompt referral to specialized units, and an early and appropriate treatment. These recommendations will provide a guidance for HoFH patient management in Spain. Copyright © 2015 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  8. The prosecution of Taiwan sexuality researcher and activist Josephine Ho.

    PubMed

    Wang, Ping

    2004-05-01

    In April 2003, following a newspaper report of a hyperlink to a website on bestiality on the Sexuality Databank website of the Center for the Study of Sexualities, National Central University, Taipei, Taiwan, 14 conservative NGOs filed charges against the Center's founder, Josephine Ho, for "propagating obscenities that corrupt traditional values." Ho has been researching sexuality and supporting freedom for marginalised sexual minorities for ten years. In a public statement in response to the charges, she said that the work of scholarly research must not be dictated by prejudice and that differences in sexual values should not be arbitrated by law and should be open for public discussion. As the legal process began in January 2004, Ho's supporters in Taiwan have called for the preservation of the Taiwan Constitutional decree on integrity and autonomy of academic research and freedom of expression on the internet, for the University to resist calls to dismiss Ho from her post, and for respect for freedom of speech and expression and the right to create spaces to educate people about non-normative sexualities.

  9. Measurements of HO2 chemical kinetics with a new detection method

    NASA Technical Reports Server (NTRS)

    Lee, L. C.; Manzanares, E. R.

    1985-01-01

    In this research program, HO2 was detected by the OH(A-X) photofragment from dissociative excitation of HO2 at 147 nm. This detection method was applied to measure the reaction rate constant of HO2 + O3. This reaction rate constant is needed for the understanding of stratospheric chemistry. Since C12 was used in the flow system, photoexcitation of C12 may produce fluorescence to interfere with the measurements. Thus, the photoexcitation process of C12 in the vacuum ultraviolet region was also examined in this research period using synchrotron radiation as a light source. The research results are summarized.

  10. Hemin induction of HO-1 protects against LPS-induced septic ileus.

    PubMed

    Bortscher, Stephan; Chang, Johannes; Vilz, Tim O; Schäfer, Nico; Sommer, Nils; Wehner, Sven; Kalff, Jörg C; Overhaus, Marcus

    2012-12-01

    Heme oxygenase (HO-1) protects against inflammation. In this study, we investigated the protective function of hemin-induced HO-1 against lipopolysaccharide (LPS)-induced ileus. Rats received LPS intraperitoneally 24 h after intraperitoneal hemin pretreatment or placebo. We also injected zinc protoporphyrin (ZnPP, 3rd group), an inhibitor of HO-1, intraperitoneally 2 h before LPS administration. To assess intestinal muscle function, we examined muscularis strip contractility in an organ bath and measured gastrointestinal transit in vivo. We investigated inflammation within the muscularis using polymerase chain reaction (interleukin [IL]-6, inducible nitric oxide synthase (iNOS), HO-1 and IL-10) 6 and 24 h after LPS. Hemin significantly improved in vitro intestinal muscularis contractility (P < 0.001). In addition, hemin prevented LPS-induced dysmotility in vivo (gastrointestinal transit, geometric center: 8.39 ± 0.33 versus 5.68 ± 0.44; P < 0.001). In Zinc protoporphyrin (ZnPP)-treated animals, both parameters were significantly decreased compared with the hemin group. Messenger RNA expression demonstrated a significant reduction in IL-6 (6 h, hemin: 127.6 ± 36.7 versus LPS: 14,431 ± 5407; 24 h: 1.58 ± 0.39 versus 11.15 ± 2.59; P < 0.01) and iNOS (6 h: 2516 ± 985 versus 50,771 ± 13,321; 24 h: 55.11 ± 10.55 versus 257.1 ± 43.18; P < 0.001) in hemin-treated animals. Anti-inflammatory HO-1 messenger RNA levels (6 h, hemin: 116.3 ± 18.55 versus LPS: 26.02 ± 3.64; 24 h: 18.46 ± 2.69 versus 2.80 ± 0.32; P < 0.001) were increased. There was no significant difference in IL-10 levels at 6 and 24 h. ZnPP reversed the anti-inflammatory hemin effects. Hemin induction of HO-1 diminishes LPS-induced sepsis. Heme oxygenase-1 has a central role in preventing sepsis-induced ileus. This benefit is reversed by HO-1 inhibition with ZnPP. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Ground-based Characterization of Earth Quasi Satellite (469219) 2016 HO3

    NASA Astrophysics Data System (ADS)

    Reddy, Vishnu; Kuhn, Olga; Thirouin, Audrey; Conrad, Al; Malhotra, Renu; Sanchez, Juan A.; Veillet, Christian

    2017-10-01

    (469219) 2016 HO3 is a small, <100 meter-size, near-Earth object (NEO) that while orbiting the Sun, also appears to circle around the Earth just beyond the Hill sphere as a Earth quasi-satellite. Only five quasi-satellites have been discovered so far, but 2016 HO3 is the most stable of them. The provenance of this object is unknown. On timescales of many centuries, 2016 HO3 remains within 38-100 lunar distance from us making it a prime target for future robotic and human exploration, provided it can be established it is indeed a natural object. In an effort to constrain its rotation period and surface composition, we observed 2016 HO3 on April 14 and 18 2017 (UTC) with the Large Binocular Telescope (LBT) and the Discovery Channel Telescope (DCT). We derive a rotation period of about 28 minutes based on our lightcurve observations. We obtained low-resolution (R ˜ 150 - 500) spectra of 2016 HO3 on 2017 April 14 (UTC) using the pair of MODS spectrographs mounted at the direct Gregorian foci of the LBT, obtaining the entire spectrum from 0.39-0.97 microns simultaneously. The visible wavelength spectrum shows a sharp rise in reflectance between 0.4-0.65 microns with a broad plateau beyond. The scatter near 0.8 microns makes it challenging to confirm the presence of a silicate absorption band at ~1 micron. Color ratios derived from the spectrum all suggest an S taxonomic type. We also derive an updated diameter of 36 meters for 2016 HO3 using an absolute magnitude of 24.3 and S-type albedo of 0.25. The derived rotation period and the spectrum are not uncommon amongst small NEOs, suggesting that 2016 HO3 is a natural object of similar provenance to other small NEOs. NASA Near-Earth Object Observations Program Grant NNX17AJ19G (PI: Reddy) funded parts of this work.

  12. HO-1-mediated macroautophagy: a mechanism for unregulated iron deposition in aging and degenerating neural tissues.

    PubMed

    Zukor, Hillel; Song, Wei; Liberman, Adrienne; Mui, Jeannie; Vali, Hojatollah; Fillebeen, Carine; Pantopoulos, Kostas; Wu, Ting-Di; Guerquin-Kern, Jean-Luc; Schipper, Hyman M

    2009-05-01

    Oxidative stress, deposition of non-transferrin iron, and mitochondrial insufficiency occur in the brains of patients with Alzheimer disease (AD) and Parkinson disease (PD). We previously demonstrated that heme oxygenase-1 (HO-1) is up-regulated in AD and PD brain and promotes the accumulation of non-transferrin iron in astroglial mitochondria. Herein, dynamic secondary ion mass spectrometry (SIMS) and other techniques were employed to ascertain (i) the impact of HO-1 over-expression on astroglial mitochondrial morphology in vitro, (ii) the topography of aberrant iron sequestration in astrocytes over-expressing HO-1, and (iii) the role of iron regulatory proteins (IRP) in HO-1-mediated iron deposition. Astroglial hHO-1 over-expression induced cytoplasmic vacuolation, mitochondrial membrane damage, and macroautophagy. HO-1 promoted trapping of redox-active iron and sulfur within many cytopathological profiles without impacting ferroportin, transferrin receptor, ferritin, and IRP2 protein levels or IRP1 activity. Thus, HO-1 activity promotes mitochondrial macroautophagy and sequestration of redox-active iron in astroglia independently of classical iron mobilization pathways. Glial HO-1 may be a rational therapeutic target in AD, PD, and other human CNS conditions characterized by the unregulated deposition of brain iron.

  13. Evolving Hořava cosmological horizons

    NASA Astrophysics Data System (ADS)

    Fathi, Mohsen; Mohseni, Morteza

    2016-09-01

    Several sets of radially propagating null congruence generators are exploited in order to form 3-dimensional marginally trapped surfaces, referred to as black hole and cosmological apparent horizons in a Hořava universe. Based on this method, we deal with the characteristics of the 2-dimensional space-like spheres of symmetry and the peculiarities of having trapping horizons. Moreover, we apply this method in standard expanding and contracting FLRW cosmological models of a Hořava universe to investigate the conditions under which the extra parameters of the theory may lead to trapped/anti-trapped surfaces both in the future and in the past. We also include the cases of negative time, referred to as the finite past, and discuss the formation of anti-trapped surfaces inside the cosmological apparent horizons.

  14. Consistency of the Health of the Nation Outcome Scales (HoNOS) at inpatient-to-community transition.

    PubMed

    Luo, Wei; Harvey, Richard; Tran, Truyen; Phung, Dinh; Venkatesh, Svetha; Connor, Jason P

    2016-04-27

    The Health of the Nation Outcome Scales (HoNOS) are mandated outcome-measures in many mental-health jurisdictions. When HoNOS are used in different care settings, it is important to assess if setting specific bias exists. This article examines the consistency of HoNOS in a sample of psychiatric patients transitioned from acute inpatient care and community centres. A regional mental health service with both acute and community facilities. 111 psychiatric patients were transferred from inpatient care to community care from 2012 to 2014. Their HoNOS scores were extracted from a clinical database; Each inpatient-discharge assessment was followed by a community-intake assessment, with the median period between assessments being 4 days (range 0-14). Assessor experience and professional background were recorded. The difference of HoNOS at inpatient-discharge and community-intake were assessed with Pearson correlation, Cohen's κ and effect size. Inpatient-discharge HoNOS was on average lower than community-intake HoNOS. The average HoNOS was 8.05 at discharge (median 7, range 1-22), and 12.16 at intake (median 12, range 1-25), an average increase of 4.11 (SD 6.97). Pearson correlation between two total scores was 0.073 (95% CI -0.095 to 0.238) and Cohen's κ was 0.02 (95% CI -0.02 to 0.06). Differences did not appear to depend on assessor experience or professional background. Systematic change in the HoNOS occurs at inpatient-to-community transition. Some caution should be exercised in making direct comparisons between inpatient HoNOS and community HoNOS scores. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  15. Measured and Modeled Hydroxyl (OH) and Hydroperoxyl (HO2) During KORUS-AQ

    NASA Astrophysics Data System (ADS)

    Brosius, A. L.; Brune, W. H.; Thames, A. B.; Miller, D. O.

    2017-12-01

    In the troposphere, hydroxyl (OH) reacts with most atmospheric pollutants, initiating their removal from the atmosphere and in some cases creating other atmospheric pollutants, such as ozone and small particles. Hydroperoxyl (HO2) also plays a role in oxidation chemistry by producing tropospheric ozone (O3). Air pollution in Korea is a combination of locally generated pollution, aged pollution from China, and the interaction of local pollution with forest emissions. Thus, OH and HO2 interact with a complex soup of chemical species over Korea, providing a stringent test for the understanding of atmospheric oxidation chemistry. During KORUS-AQ, we measured OH and HO2 using the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) as part of a large instrument suite installed on the NASA DC-8 aircraft. We use the Master Chemical Mechanism (MCM), constrained by the simultaneous measurement of many of chemical species to calculate OH and HO2. While the measured and modeled OH and HO2 generally agree within combined uncertainties, there are substantial discrepancies. We will discuss possible reasons for the discrepancies and the implications for air quality regulatory policy.

  16. Ab initio thermal rate calculations of HO + HO = O(3P) + H2O reaction and isotopologues.

    PubMed

    Nguyen, Thanh Lam; Stanton, John F

    2013-04-04

    The forward and reverse reactions, HO + HO ⇌ O((3)P) + H2O, which play roles in both combustion and laboratory studies, were theoretically characterized with a master equation approach to compute thermal reaction rate constants at both the low and high pressure limits. Our ab initio k(T) results for the title reaction and two isotopic variants agree very well with experiments (within 15%) over a wide temperature range. The calculated reaction rate shows a distinctly non-Arrhenius behavior and a strong curvature consistent with the experiment. This characteristic behavior is due to effects of positive barrier height and quantum mechanical tunneling. Tunneling is very important and contributes more than 70% of total reaction rate at room temperature. A prereactive complex is also important in the overall reaction scheme.

  17. High-frequency spectral ultrasound imaging (SUSI) visualizes early post-traumatic heterotopic ossification (HO) in a mouse model.

    PubMed

    Ranganathan, Kavitha; Hong, Xiaowei; Cholok, David; Habbouche, Joe; Priest, Caitlin; Breuler, Christopher; Chung, Michael; Li, John; Kaura, Arminder; Hsieh, Hsiao Hsin Sung; Butts, Jonathan; Ucer, Serra; Schwartz, Ean; Buchman, Steven R; Stegemann, Jan P; Deng, Cheri X; Levi, Benjamin

    2018-04-01

    Early treatment of heterotopic ossification (HO) is currently limited by delayed diagnosis due to limited visualization at early time points. In this study, we validate the use of spectral ultrasound imaging (SUSI) in an animal model to detect HO as early as one week after burn tenotomy. Concurrent SUSI, micro CT, and histology at 1, 2, 4, and 9weeks post-injury were used to follow the progression of HO after an Achilles tenotomy and 30% total body surface area burn (n=3-5 limbs per time point). To compare the use of SUSI in different types of injury models, mice (n=5 per group) underwent either burn/tenotomy or skin incision injury and were imaged using a 55MHz probe on VisualSonics VEVO 770 system at one week post injury to evaluate the ability of SUSI to distinguish between edema and HO. Average acoustic concentration (AAC) and average scatterer diameter (ASD) were calculated for each ultrasound image frame. Micro CT was used to calculate the total volume of HO. Histology was used to confirm bone formation. Using SUSI, HO was visualized as early as 1week after injury. HO was visualized earliest by 4weeks after injury by micro CT. The average acoustic concentration of HO was 33% more than that of the control limb (n=5). Spectroscopic foci of HO present at 1week that persisted throughout all time points correlated with the HO present at 9weeks on micro CT imaging. SUSI visualizes HO as early as one week after injury in an animal model. SUSI represents a new imaging modality with promise for early diagnosis of HO. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Level structure of 154Ho

    NASA Astrophysics Data System (ADS)

    Moon, Chang-Bum; Komatsubara, Tetsuro; Furuno, Kohei

    2013-10-01

    The excited states of the odd-odd 154Ho nucleus have been studied by using in-beam γ-ray spectroscopy with the 141Pr (16O, 3n) 154Ho reaction at Elab=75 MeV. The beam was provided by the 12UD Pelletron accelerator at the University of Tsukuba. In this work, the complicated decay pattern of low energy transitions just above the T1/2=3.10 min isomer have been established. In addition, a number of new states and γ-ray transitions, especially those associated with energetically favored band termination, have been observed for the first time in 154Ho. A negative collective band and its signature partner built on the 11- level are interpreted as being based on the πh11/2⊗νi13/2 configuration. A positive band built on the 10+ level is based on the πh11/2⊗νh9/2 configuration while another positive band built on the 9+ level is being associated with the πh11/2⊗νf7/2 configuration. An energetically favored level Jπ=19- can be interpreted as being attributed to the πh11/2⊗νi13/2 configuration coupled to the 8+ state in neighboring core 152Dy, namely, a four-quasiparticle alignment based on the [πh11/2νi13/2]11-⊗[ν(h9/2f7/2)]8- configuration. Another energetically favored state at Jπ=27- is assigned the six-quasiparticle [π(h11/2)3]27/2-⊗[ν(f7/2h9/2i13/2)]27/2- configuration.

  19. Growth and lasing of single crystal YAG fibers with different Ho3+ concentrations

    NASA Astrophysics Data System (ADS)

    Bera, Subhabrata; Nie, Craig D.; Soskind, Michael G.; Li, Yuan; Harrington, James A.; Johnson, Eric G.

    2018-01-01

    A method to grow single crystal (SC) yttrium aluminum garnet (YAG) fibers with varied rare-earth ion dopant concentration has been proposed. Crystalline holmium aluminum garnet (HoAG), prepared via sol-gel process, was dip-coated on to previously grown SC YAG fibers. The HoAG coated SC YAG fiber preforms were re-grown to a smaller diameter using the laser heated pedestal growth (LHPG) technique. The final dopant concentration of the re-grown SC fiber was varied by changing the number of HoAG coatings on the preform. 120 μm diameter SC Ho:YAG fibers with four different dopant concentrations were grown. Lasing was demonstrated at 2.09 μm for these fibers. A maximum of 58.5% optical-to-optical slope efficiency was obtained.

  20. Energy transfer in Tm,Ho:KYW crystal and diode-pumped microchip laser operation.

    PubMed

    Kurilchik, Sergey; Gusakova, Natali; Demesh, Maxim; Yasukevich, Anatol; Kisel, Viktor; Pavlyuk, Anatoly; Kuleshov, Nikolai

    2016-03-21

    An investigation of Tm-Ho energy transfer in Tm(5at.%),Ho(0.4at.%):KYW single crystal by two independent techiques was performed. Based on fluorescence dynamics measurements, energy transfer parameters P71 and P28 for direct (Tm→Ho) and back (Ho→Tm) transfers, respectively, as well as equilibrium constant Θ were evaluated. The obtained results were supported by calculation of microscopic interaction parameters according to the Förster-Dexter theory for a dipole-dipole interaction. Diode-pumped continuous-wave operation of Tm,Ho:KYW microchip laser was demonstrated, for the first time to our knowledge. Maximum output power of 77 mW at 2070 nm was achieved at the fundamental TEM00 mode.

  1. Temperature Dependence of the O + HO2 Rate Coefficient

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Wine, P. H.

    1997-01-01

    A pulsed laser photolysis technique has been employed to investigate the kinetics of the radical-radical reaction O((sup 3)P) + HO2 OH + O2 over the temperature range 266-391 K in 80 Torr of N2 diluent gas. O((sup 3)P) was produced by 248.5-nm KrF laser photolysis of O3 followed by rapid quenching of O(1D) to O((sup 3)P) while HO2 was produced by simultaneous photolysis of H2O2 to create OH radicals which, in turn, reacted with H2O2 to yield HO2. The O((sup 3)P) temporal profile was monitored by using time-resolved resonance fluorescence spectroscopy. The HO2 concentration was calculated based on experimentally measured parameters. The following Arrhenius expression describes our experimental results: k(sub 1)(T) equals (2.91 +/- 0.70) x 10(exp -11) exp[(228 +/- 75)/T] where the errors are 2 sigma and represent precision only. The absolute uncertainty in k, at any temperature within the range 266-391 K is estimated to be +/- 22 percent. Our results are in excellent agreement with a discharge flow study of the temperature dependence of k(sub 1) in 1 Torr of He diluent reported by Keyser, and significantly reduce the uncertainty in the rate of this important stratospheric reaction at subambient temperatures.

  2. HoCP 04-838 – A new sugarcane variety for Louisiana

    USDA-ARS?s Scientific Manuscript database

    HoCP 04-838 was released to the Louisiana sugar industry on May 3, 2011 by the Agricultural Research Service of the United States Department of Agriculture in cooperation with the Louisiana State University Agricultural Center, and the American Sugar Cane League of the U.S.A., Inc. HoCP 04-838 re...

  3. Prompt HO2 formation following the reaction of OH with aromatic compounds under atmospheric conditions.

    PubMed

    Nehr, Sascha; Bohn, Birger; Wahner, Andreas

    2012-06-21

    The secondary formation of HO(2) radicals following OH + aromatic hydrocarbon reactions in synthetic air under normal pressure and temperature was investigated in the absence of NO after pulsed production of OH radicals. OH and HO(x) (=OH + HO(2)) decay curves were recorded using laser-induced fluorescence after gas-expansion. The prompt HO(2) yields (HO(2) formed without preceding NO reactions) were determined by comparison to results obtained with CO as a reference compound. This approach was recently introduced and applied to the OH + benzene reaction and was extended here for a number of monocyclic aromatic hydrocarbons. The measured HO(2) formation yields are as follows: toluene, 0.42 ± 0.11; ethylbenzene, 0.53 ± 0.10; o-xylene, 0.41 ± 0.08; m-xylene, 0.27 ± 0.06; p-xylene, 0.40 ± 0.09; 1,2,3-trimethylbenzene, 0.31 ± 0.06; 1,2,4-trimethylbenzene, 0.37 ± 0.09; 1,3,5-trimethylbenzene, 0.29 ± 0.08; hexamethylbenzene, 0.32 ± 0.08; phenol, 0.89 ± 0.29; o-cresol, 0.87 ± 0.29; 2,5-dimethylphenol, 0.72 ± 0.12; 2,4,6-trimethylphenol, 0.45 ± 0.13. For the alkylbenzenes HO(2) is the proposed coproduct of phenols, epoxides, and possibly oxepins formed in secondary reactions with O(2). In most product studies the only quantified coproducts were phenols whereas only a few studies reported yields of epoxides. Oxepins have not been observed so far. Together with the yields of phenols from other studies, the HO(2) yields determined in this work set an upper limit to the combined yields of epoxides and oxepins that was found to be significant (≤0.3) for all investigated alkylbenzenes except m-xylene. For the hydroxybenzenes the currently proposed HO(2) coproducts are dihydroxybenzenes. For phenol and o-cresol the determined HO(2) yields are matching the previously reported dihydroxybenzene yields, indicating that these are the only HO(2) forming reaction channels. For 2,5-dimethylphenol and 2,4,6-trimethylphenol no complementary product studies are available.

  4. The HoMBReS and HoMBReS Por un Cambio Interventions to Reduce HIV Disparities Among Immigrant Hispanic/Latino Men

    PubMed Central

    Rhodes, Scott D.; Leichliter, Jami S.; Sun, Christina J.; Bloom, Fred R.

    2016-01-01

    Summary Hispanics/Latinos in the United States are affected disproportionately by human immunodeficiency virus (HIV) infection, acquired immunodeficiency syndrome (AIDS), and other sexually transmitted diseases (STDs); however, few effective evidence-based prevention interventions for this population exist. This report describes the Hombres Manteniendo Bienestar y Relaciones Saludables (Men Maintaining Wellbeing and Healthy Relationships) (HoMBReS) intervention, which was developed by a community-based, participatory research partnership in North Carolina and initially implemented during 2005–2009. HoMBReS is an example of an effective intervention that uses lay health advisors (known as Navegantes [navigators]) in the context of existing social networks (i.e., recreational soccer teams) to promote consistent condom use and HIV and STD testing among Hispanic/Latino men. In 2012, HoMBReS was classified as a best-evidence community-level HIV prevention intervention (CDC. Compendium of evidence-based behavioral interventions and best practices for HIV prevention. Atlanta, GA: US Department of Health and Human Services, CDC; 2015). The intervention has been implemented elsewhere, enhanced, and further evaluated in longitudinal intervention and implementation studies. HoMBReS has been adapted for other populations, including men who have sex with men and transgender persons. Additional evaluation has found that Navegantes continue in their roles as health advisors, opinion leaders, and community advocates after study support ends. Hispanic/Latino men’s social networks can be leveraged to promote sexual health within the community by decreasing HIV risk behaviors among Hispanics/Latinos in the United States. PMID:26916740

  5. Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163Ho ions

    NASA Astrophysics Data System (ADS)

    Gastaldo, L.; Ranitzsch, P. C.-O.; von Seggern, F.; Porst, J.-P.; Schäfer, S.; Pies, C.; Kempf, S.; Wolf, T.; Fleischmann, A.; Enss, C.; Herlert, A.; Johnston, K.

    2013-05-01

    For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of 163Ho using MMCs having the radioactive 163Ho ions implanted in the absorber. The isotope 163Ho decays through electron capture to 163Dy and features the smallest known QEC value. This peculiarity makes 163Ho a very interesting candidate to investigate the value of the electron neutrino mass by the analysis of the energy spectrum. The implantation of 163Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. Moreover the performance of the detector prototype having the 163Ho ions implanted in the absorber is already close to the requirements needed for an experiment with sub-eV sensitivity to the electron neutrino mass. Based on these results, an optimized detector design for future 163Ho experiments is presented.

  6. Ho 07-613 – A potential new sugarcane variety for Louisiana

    USDA-ARS?s Scientific Manuscript database

    The clone Ho 07-613 will be up for release to Louisiana sugarcane farmers in May of 2014. This potential new variety is a joint release of the United States Department of Agriculture, the Louisiana State University Agricultural Center, and the American Sugar Cane League of the U.S.A., Inc. Ho 07-613...

  7. Yb3+/Ho3+-codoped antimony-silicate optical fiber

    NASA Astrophysics Data System (ADS)

    Żmojda, Jacek; Dorosz, Dominik; Kochanowicz, Marcin; Miluski, Piotr; Dorosz, Jan

    2012-05-01

    The emission properties of Yb3+/Ho3+-codoped antimony-silicate optical fiber has been investigated. Luminescence at 2.1 μm corresponding to 5I7--> 5I8 transition in holmium was obtained by energy transfer between Yb3+ and Ho3+ ions. According to the Dexter-Miyakawa model, the parameters of energy migration CDD of the 2F5/2 (Yb3+) <--> 2F5/2 (Yb3+) transition and direct energy transfer CDA of the 2F5/2 (Yb3+) --> 5I6 (Ho3+) transition was calculated. The optimization of the activator content and the concentration ratio were conducted with the purpose of maximizing the efficiency of energy transfer. It made possible to select best-suited glass which was used to manufacture double-clad optical fiber. Strong and narrow bands of spontaneous emission which formed as a result of energy transfer between ytterbium and holmium ions were observed in the fiber under exciting with radiation at 978 nm wavelength.

  8. Scale invariance in Newton–Cartan and Hořava–Lifshitz gravity

    NASA Astrophysics Data System (ADS)

    Olgu Devecioğlu, Deniz; Özdemir, Neşe; Ozkan, Mehmet; Zorba, Utku

    2018-06-01

    We present a detailed analysis of the construction of z  =  2 and scale invariant Hořava–Lifshitz gravity. The construction procedure is based on the realization of Hořava–Lifshitz gravity as the dynamical Newton–Cartan geometry as well as a non-relativistic tensor calculus in the presence of the scale symmetry. An important consequence of this method is that it provides us with the necessary mechanism to distinguish the local scale invariance from the local Schrödinger invariance. Based on this result we discuss the z  =  2 scale invariant Hořava–Lifshitz gravity and the symmetry enhancement to the full Schrödinger group.

  9. Preparation and spectroscopic characterization of two HoCl 3-galactitol complexes and one ErCl 3-galactitol complex

    NASA Astrophysics Data System (ADS)

    Hua, Xiaohui; Pan, Qinghua; Yu, Lei; Xue, Junhui; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Li, Weihong; Wang, Zheming; Wu, Jinguang; Liu, Kexin; Chen, Jia'er

    2011-07-01

    The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl 3-galactitol complexes ([Ho(galac)(H 2O) 3)]Cl 3·0.5galac) (HoG(I)) and ([Ho 2(galac)(H 2O) 12)]Cl 6·2H 2O) (HoG(II))) and one ErCl 3-galactitol complex ([Er(galac)(H 2O) 3)]Cl 3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho 3+ or Er 3+ is 9-coordinated with six hydroxyl groups from two galactitol molecules and three water molecules, and another galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with galactitol may form two compounds in a system and different topological structures can be obtained.

  10. Simultaneous, in situ measurements of OH and HO2 in the stratosphere

    NASA Technical Reports Server (NTRS)

    Stimpfle, R. M.; Wennberg, P. O.; Lapson, L. B.; Anderson, J. G.

    1990-01-01

    Stratospheric OH and HO2 radical densities have been measured between 36 and 23 km using a balloon-borne, in situ instrument launched from Palestine, Texas on August 25, 1989. OH is detected using the laser-induced fluorescence technique (LIF) employing a Cu-vapor-laser pumped dye laser coupled with an enclosed-flow detection chamber. HO2 is detected nearly simultaneously by adding NO to the sample flow to convert ambient HO2 to OH. Observed OH and HO2 densities ranged from 8.0 + or - 2.8 x 10 to the 6th and 1.4 + or - 0.5 x 10 to the 7th molec/cu cm, respectively, at 36 km, to 1.4 + or - 0.5 x 10 to the 6th and 3.0 + or - 1.0 x 10 to the 6th at 23 km, where the uncertainty is + or - sigma. The HO2 density exhibits a maximum in the 34-30 km region of 1.7 + or - 0.6 x 10 to the 7th. The data were obtained over a solar zenith angle variation of 51 deg at 36 km to 61 deg at 23 km. O3 and H2O densitites also were measured simultaneously with separate instruments.

  11. Impacts of doping concentration on the saturable characteristics of Tm-Ho codoped fiber saturable absorber

    NASA Astrophysics Data System (ADS)

    Tao, Mengmeng; Feng, Guobin; Yu, Ting; Ye, Xisheng; Wang, Zhenbao; Shen, Yanlong; Zhao, Jun

    2018-03-01

    Impacts of Tm ion concentration and Ho ion concentration on the saturable behaviors of Tm-Ho codoped fiber saturable absorbers and the output characteristics of the passively Q-switched laser systems are investigated and analyzed both at the initial lasing state and the stable passive Q-switching state. Simulations show that, varying concentrations of Tm and Ho ions have different impacts on the temporal evolution processes but similar effects on the macroscopic characteristics of the laser system. The root for the impacts of dopant concentrations is the population of the 3H6 energy level and the cavity loss it induces. For Tm ions, the rise of the Tm concentration improves the population of the 3H6 energy level directly, while, for Ho ions, higher Ho concentration leads to larger recovery rate of the 3H6 energy level, thus increasing the population of the 3H6 energy level indirectly. As for limited total dopant concentration, the Tm:Ho concentration ratio can be optimized for different applications.

  12. A review and update of the Health of the Nation Outcome Scales (HoNOS).

    PubMed

    James, Mick; Painter, Jon; Buckingham, Bill; Stewart, Malcolm W

    2018-04-01

    Aims and method The Health of the Nation Outcome Scales (HoNOS) and its older adults' version (HoNOS 65+) have been used widely for 20 years, but their glossaries have not been revised to reflect clinicians' experiences or changes in service delivery. The Royal College of Psychiatrists convened an international advisory board, with UK, Australian and New Zealand expertise, to identify desirable amendments. The aim was to improve rater experience by removing ambiguity and inconsistency in the glossary rather than more radical revision. Changes proposed to the HoNOS are reported. HoNOS 65+ changes will be reported separately. Based on the views and experience of the countries involved, a series of amendments were identified. Clinical implications While effective clinician training remains critically important, these revisions aim to improve intra- and interrater reliability and improve validity. Next steps will depend on feedback from HoNOS users. Reliability and validity testing will depend on funding. Declaration of interest None.

  13. Lung endothelial HO-1 targeting in vivo using lentiviral miRNA regulates apoptosis and autophagy during oxidant injury

    PubMed Central

    Zhang, Yi; Jiang, Ge; Sauler, Maor; Lee, Patty J.

    2013-01-01

    The lung endothelium is a major target for inflammatory and oxidative stress. Heme oxygenase-1 (HO-1) induction is a crucial defense mechanism during oxidant challenges, such as hyperoxia. The role of lung endothelial HO-1during hyperoxia in vivo is not well defined. We engineered lentiviral vectors with microRNA (miRNA) sequences controlled by vascular endothelium cadherin (VE-cad) to study the specific role of lung endothelial HO-1. Wild-type (WT) murine lung endothelial cells (MLECs) or WT mice were treated with lentivirus and exposed to hyperoxia (95% oxygen). We detected HO-1 knockdown (∼55%) specifically in the lung endothelium. MLECs and lungs showed approximately a 2-fold increase in apoptosis and ROS generation after HO-1 silencing. We also demonstrate for the first time that silencing endothelial HO-1 has the same effect on lung injury and survival as silencing HO-1 in multiple lung cell types and that HO-1 regulates caspase 3 activation and autophagy in endothelium during hyperoxia. These studies demonstrate the utility of endothelial-targeted gene silencing in vivo using lentiviral miRNA constructs to assess gene function and that endothelial HO-1 is an important determinant of survival during hyperoxia.—Zhang, Y., Jiang, G., Sauler, M., Lee, P. J. Lung endothelial HO-1 targeting in vivo using lentiviral miRNA regulates apoptosis and autophagy during oxidant injury. PMID:23771928

  14. Modulation of cGMP by human HO-1 retrovirus gene transfer in pulmonary microvessel endothelial cells.

    PubMed

    Abraham, Nader G; Quan, Shuo; Mieyal, Paul A; Yang, Liming; Burke-Wolin, Theresa; Mingone, Christopher J; Goodman, Alvin I; Nasjletti, Alberto; Wolin, Michael S

    2002-11-01

    Carbon monoxide (CO) stimulates guanylate cyclase (GC) and increases guanosine 3',5'-cyclic monophosphate (cGMP) levels. We transfected rat-lung pulmonary endothelial cells with a retrovirus-mediated human heme oxygenase (hHO)-1 gene. Pulmonary cells that expressed hHO-1 exhibited a fourfold increase in HO activity associated with decreases in the steady-state levels of heme and cGMP without changes in soluble GC (sGC) and endothelial nitric oxide synthase (NOS) proteins or basal nitrite production. Heme elicited significant increases in CO production and intracellular cGMP levels in both pulmonary endothelial and pulmonary hHO-1-expressing cells. N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NOS, significantly decreased cGMP levels in heme-treated pulmonary endothelial cells but not heme-treated hHO-1-expressing cells. In the presence of exogenous heme, CO and cGMP levels in hHO-1-expressing cells exceeded the corresponding levels in pulmonary endothelial cells. Acute exposure of endothelial cells to SnCl2, which is an inducer of HO-1, increased cGMP levels, whereas chronic exposure decreased heme and cGMP levels. These results indicate that prolonged overexpression of HO-1 ultimately decreases sGC activity by limiting the availability of cellular heme. Heme activates sGC and enhances cGMP levels via a mechanism that is largely insensitive to NOS inhibition.

  15. Near IR Photolysis of HO2NO2: Supplemental Material

    NASA Technical Reports Server (NTRS)

    2002-01-01

    MkIV measurements of the volume mixing ratio (VMR) of HO2NO2 at 35 deg N, sunset on Sept. 25, 1993 are given. Measurements of HO2NO2 made between approx. 65 and 70 deg N, sunrise on May 8, 1997 are listed. The uncertainties given are 1 sigma estimates of the measurement precision. Uncertainty in the HO2NO2 line strengths is estimated to be 20%; this is the dominant contribution to the systematic error of the HO2NO2 measurement. Model inputs for the simulations are given. The albedos were obtained from Total Ozone Mapping Spectrometer reflectively data (raw data at ftp://jwocky.gsfc.nasa.gov) for the time and place of observation. Profiles of sulfate aerosol surface area ("Surf. Area") were obtained from monthly, zonal mean profiles measured by SAGE II [Thomason et al., 1997 updated via private communication]. The profile of Be(y) is based on the Wamsley et al. relation with N2O, using MkIV measurements of N20O. All other model inputs given are based on direct MkIV measurements. Finally, we note the latitude of the MkIV tangent point varied considerably during sunrise on May 8, 1997. The simulations shown here were obtained using different latitudes for each altitude.

  16. New rotational bands in sup 166 Ho

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sheline, R.K.; Sood, P.C.; Baluba Mutshil

    1989-08-01

    The {ital K}{sup {pi}}=1{sup {minus}} and 0{sup {minus}} bands from the (1/2{sup +}(411){plus minus}(1/2{sup {minus}}(521))) configuration, and the {ital K}{sup {pi}}=1{sup {minus}} and 2{sup {minus}} bands from the (3/2{sup +}(411){plus minus}(1/2{sup {minus}}(521))) configuration have been identified for the first time largely using known but previously unused gamma transitions from the {sup 165}Ho({ital n},{gamma}) reaction. A remarkable similarity is shown to exist between the level structures of the {ital K}{sup {pi}}=1{sup {minus}} and 0{sup {minus}} bands from the (1/2{sup +}(411){plus minus}(1/2{sup {minus}}(521))) configurations in {sup 170}Tm and {sup 166}Ho.

  17. Crystal Growth and Scintillation Properties of Ho-Doped Lu3Al5O12 Single Crystals

    NASA Astrophysics Data System (ADS)

    Sugiyama, Makoto; Yanagida, Takayuki; Fujimoto, Yutaka; Totsuka, Daisuke; Yokota, Yuui; Kurosawa, Shunsuke; Futami, Yoshisuke; Yoshikawa, Akira

    2012-10-01

    The crystals of 0.1, 0.5, 1, and 3% Ho doped Lu3Al5O12 (Ho:LuAG) grown by the micro-pulling-down method were examined for their scintillation properties. At wavelengths longer than 300 nm, Ho:LuAG crystals demonstrated around 60% transparency with many absorption peaks attributed to Ho3+ 4f10-4 f10 transitions. When excited by 241Am α-ray to obtain radio luminescence spectra, broad host emission and four sharp Ho3+ 4f10-4 f10 emission peaks were detected in the visible region. Light yields and decay time profiles of the samples irradiated by 137Cs γ-ray were measured using photomultiplier tubes R7600 (Hamamatsu). Ho 0.5%:LuAG showed the highest light yield of 3100 ±310 photons/MeV among the present samples. The decay time profiles were well reproduced by two components exponential approximation consisting of 0.5-1 μs and 3-6 μs.

  18. High-power and highly efficient diode-cladding-pumped Ho3+-doped silica fiber lasers.

    PubMed

    Jackson, Stuart D; Bugge, Frank; Erbert, Götz

    2007-11-15

    We demonstrate high-power operation from a singly Ho3+-doped silica fiber laser that is cladding pumped directly with diode lasers operating at 1150 nm. Internal slope efficiencies approaching the Stokes limit were produced, and the maximum output power was 2.2W. This result was achieved using a low Ho3+-ion concentration and La3+-ion codoping, which together limit the transfer of energy between excited Ho3+ ions.

  19. Magnetostriction of Hexagonal HoMnO3 and YMnO3 Single Crystals

    NASA Astrophysics Data System (ADS)

    Pavlovskii, N. S.; Dubrovskii, A. A.; Nikitin, S. E.; Semenov, S. V.; Terent'ev, K. Yu.; Shaikhutdinov, K. A.

    2018-03-01

    We report on the magnetostriction of hexagonal HoMnO3 and YMnO3 single crystals in a wide range of applied magnetic fields (up to H = 14 T) at all possible combinations of the mutual orientations of magnetic field H and magnetostriction Δ L/L. The measured Δ L/L( H, T) data agree well with the magnetic phase diagram of the HoMnO3 single crystal reported previously by other authors. It is shown that the nonmonotonic behavior of magnetostriction of the HoMnO3 crystal is caused by the Ho3+ ion; the magnetic moment of the Mn3+ ion parallel to the hexagonal crystal axis. The anomalies established from the magnetostriction measurements of HoMnO3 are consistent with the phase diagram of these compounds. For the isostructural YMnO3 single crystal with a nonmagnetic rare-earth ion, the Δ L/L( H, T) dependences are described well by a conventional quadratic law in a wide temperature range (4-100 K). In addition, the magnetostriction effect is qualitatively estimated with regard to the effect of the crystal electric field on the holmium ion.

  20. Crystal-field effects in the kagome antiferromagnet Ho3Ru4Al12

    NASA Astrophysics Data System (ADS)

    Gorbunov, D. I.; Nomura, T.; Ishii, I.; Henriques, M. S.; Andreev, A. V.; Doerr, M.; Stöter, T.; Suzuki, T.; Zherlitsyn, S.; Wosnitza, J.

    2018-05-01

    In Ho3Ru4Al12 , the Ho atoms form a distorted kagome lattice. We performed magnetization, magnetic-susceptibility, specific-heat, and ultrasound measurements on a single crystal. We find that the magnetic and magnetoelastic properties of Ho3Ru4Al12 result from an interplay between geometric frustration and crystal-electric-field (CEF) effects. The Ho atoms order antiferromagnetically at TN=4.5 K with reduced magnetic moments. In applied field, the magnetization shows anomalies that can be explained by CEF level crossings. We propose a CEF level scheme for which the ground-state doublet and the first two excited singlets at about 2.7 K form a quasiquartet. Indirect interlevel transitions allow for a quadrupolar interaction. This interaction explains well changes in the elastic shear modulus C44 as a function of temperature and magnetic field.

  1. Determination of hydroxylated polychlorinated biphenyls (HO-PCBs) in blood plasma by high-performance liquid chromatography-electrospray ionization-tandem quadrupole mass spectrometry.

    PubMed

    Letcher, R J; Li, H X; Chu, S G

    2005-01-01

    Hydroxylated metabolites of polychlorinated biphenyls (HO-PCBs) and pentachlorophenol (PCP) are halogenated phenolic compounds, and they are increasingly common as environmental contaminants mainly in the blood of wildlife and humans. A methodology based on high-performance liquid chromatography (reversed-phase)-electrospray (negative) ionization-tandem quadrupole mass spectrometry (LC-ESI(-)-MS-MS) in the select ion monitoring or multiple reaction monitoring modes was developed for HO-PCB and PCP determination in blood plasma and serum. Among 11 environmentally relevant HO-PCB congeners and PCP spiked to fetal calf serum, quantitative assessments, including matrix effects on ESI(-) suppression/ enhancement, showed process (recovery) efficiencies of 73% to 89% without internal standard (IS) correction, and 88% to 103% with IS correction, and method limits of quantification ranging from 1 to 50 pg/g (wet weight). Using the developed LC-ESI(-)-MS methodology in comparison with GC-MS and GC-ECD based approaches, similar results were found for HO-PCB identification and quantification in the plasma of polar bear (Ursus maritimus) from the Canadian arctic. LC-ESI(-)-MS identified four HO-PCB congeners [4'-HO-2,2',4,6,6'-pentachlorobiphenyl (4'-HO-CB104), 4-HO-2,3,3',4',5-pentachlorobiphenyl (4-HO-CB107), 4-HO-2,3,3',5,5',6-hexachlorobiphenyl (4-HO-CB165) and 3'-HO-2,2',3,4,4',5,5'-heptachlorobiphenyl (3'-HO-CB180)], and 14 additional tetra- to hepta-chlorinated HO-PCBs isomers in the polar bear plasma.

  2. Mechanical properties, in vitro corrosion and biocompatibility of newly developed biodegradable Mg-Zr-Sr-Ho alloys for biomedical applications

    PubMed Central

    Ding, Yunfei; Lin, Jixing; Wen, Cuie; Zhang, Dongmei; Li, Yuncang

    2016-01-01

    Our previous studies have demonstrated that Mg-Zr-Sr alloys can be anticipated as excellent biodegradable implant materials for load-bearing applications. In general, rare earth elements (REEs) are widely used in magnesium (Mg) alloys with the aim of enhancing the mechanical properties of Mg-based alloys. In this study, the REE holmium (Ho) was added to an Mg-1Zr-2Sr alloy at different concentrations of Mg1Zr2SrxHo alloys (x = 0, 1, 3, 5 wt. %) and the microstructure, mechanical properties, degradation behaviour and biocompatibility of the alloys were systematically investigated. The results indicate that the addition of Ho to Mg1Zr2Sr led to the formation of the intermetallic phases MgHo3, Mg2Ho and Mg17Sr2 which resulted in enhanced mechanical strength and decreased degradation rates of the Mg-Zr-Sr-Ho alloys. Furthermore, Ho addition (≤5 wt. %) to Mg-Zr-Sr alloys led to enhancement of cell adhesion and proliferation of osteoblast cells on the Mg-Zr-Sr-Ho alloys. The in vitro biodegradation and the biocompatibility of the Mg-Zr-Sr-Ho alloys were both influenced by the Ho concentration in the Mg alloys; Mg1Zr2Sr3Ho exhibited lower degradation rates than Mg1Zr2Sr and displayed the best biocompatibility compared with the other alloys. PMID:27553403

  3. The Pacific Northwest Hydrological Observatory (PNW HO): Hypothesis and model testing power through diversity

    NASA Astrophysics Data System (ADS)

    McDonnell, J. J.; Grant, G.; Hulse, D.

    2004-12-01

    The Pacific Northwest Hydrological Observatory (PNW HO) is a proposed national facility for the examination of the linkages between hydrologic and biogeochemical cycles, sustainability of water resources in the face of increasing human demands and climate change, hydrologic and ecosystem interactions, and hydrologic extremes. The PNW HO infrastructure will support research that examines forcings, feedbacks and couplings across hydro-eco-climatic interfaces, process scaling, and development of new predictive schemes and methods to reduce predictive uncertainty. Much of the data collection infrastructure is already in place, in the form of USGS gauging, local and State data recording. The PNW HO includes a novel experimental design that twins two neighboring watersheds-the humid Willamette and arid Deschutes River Basins-that represent a full range of landscape gradients and societal problems relating to water quantity and quality. Workers at the PNW HO will be able to build upon existing synthesis documents in the form of the Willamette River Basin Planning Atlas and recent AGU Monograph on the Deschutes River Basin. The PNW HO design builds upon the HJ Andrews LTER site in the headwaters and recent listing of the Willamette River Basin as a UNESCO HELP international observatory. The PNW HO has access to one of the richest SNOTEL datasets in North America along the divide between the Willamette and Deschutes Basins. The Willamette is a USGS NAWQA basin and the Deschutes has been the focus of a major USGS groundwater investigation, and is one of five sites nationally in the Fire Learning Network. Finally, and perhaps most importantly for technology transfer of HO science to policy and practice, the PNW HO enjoys a rather unique combination of Oregon's state-based land use planning and doctrine of prior appropriations water law (land use planning and water rights). While there are certainly areas in the West where human populations are growing as fast or faster, none

  4. Heat exchanger panel

    NASA Technical Reports Server (NTRS)

    Warburton, Robert E. (Inventor); Cuva, William J. (Inventor)

    2005-01-01

    The present invention relates to a heat exchanger panel which has broad utility in high temperature environments. The heat exchanger panel has a first panel, a second panel, and at least one fluid containment device positioned intermediate the first and second panels. At least one of the first panel and the second panel have at least one feature on an interior surface to accommodate the at least one fluid containment device. In a preferred embodiment, each of the first and second panels is formed from a high conductivity, high temperature composite material. Also, in a preferred embodiment, the first and second panels are joined together by one or more composite fasteners.

  5. Reliability and Validity of the HoNOS-LD and HoNOS in a Sample of Individuals with Mild to Borderline Intellectual Disability and Severe Emotional and Behavior Disorders

    ERIC Educational Resources Information Center

    Tenneij, Nienke; Didden, Robert; Veltkamp, Eline; Koot, Hans M.

    2009-01-01

    In this study, psychometric properties of the Health of the Nation Outcome scales (HoNOS) and Health of the Nation Outcome Scales for People with Learning Disabilities (HoNOS-LD) were investigated in a sample (n = 79) of (young) adults with mild to borderline intellectual disability (ID) and severe behavior and mental health problems who were…

  6. Nutlin-3 induces HO-1 expression by activating JNK in a transcription-independent manner of p53.

    PubMed

    Choe, Yun-Jeong; Lee, Sun-Young; Ko, Kyung Won; Shin, Seok Joon; Kim, Ho-Shik

    2014-03-01

    A recent study reported that p53 can induce HO-1 by directly binding to the putative p53 responsive element in the HO-1 promoter. In this study, we report that nutlin-3, a small molecule antagonist of HDM2, induces the transcription of HO-1 in a transcription-independent manner of p53. Nutlin-3 induced HO-1 expression at the level of transcription in human cancer cells such as U2OS and RKO cells. This induction of HO-1 did not occur in SAOS cells in which p53 was mutated and was prevented by knocking down the p53 protein using p53 siRNA transfection, but not by PFT-α, an inhibitor of the transcriptional activity of p53. Accompanying HO-1 expression, nutlin-3 stimulated the accumulation of ROS and the phosphorylation of MAPKs such as JNK, p38 MAPK and ERK1/2. Nutlin-3-induced HO-1 expression was suppressed by TEMPO, a ROS scavenger, and chemical inhibitors of JNK and p38 MAPK but not ERK1/2. In addition, nutlin‑3-induced phosphorylation of JNK but not p38 MAPK was inhibited by TEMPO. Notably, the levels of nutlin-3-induced ROS were correlated with the mitochondrial translocation of p53 and this induction was prevented by PFT-μ, an inhibitor of the mitochondrial translocation of p53. Consistent with the effect of the ROS scavenger and MAPK inhibitors, PFT-μ reduced HO-1 expression and the phosphorylation of JNK induced by nutlin-3. In the experiments of analyzing cell death, the knockdown of HO-1 augmented nutlin-3-induced apoptosis. Collectively, these results suggest that nutlin-3 induces HO-1 expression via the activation of both JNK which is dependent on ROS generated by p53 translocated to the mitochondria and p38 MAPK which appears to be stimulated by a ROS-independent mechanism, and this HO-1 induction may inhibit nutlin-3-induced apoptosis, constituting a negative feedback loop of p53-induced apoptosis.

  7. Optical spectroscopy and luminescence properties of Ho3+ doped zinc fluorophosphate (ZFP) glasses for green luminescent device applications

    NASA Astrophysics Data System (ADS)

    Reddy Prasad, V.; Damodaraiah, S.; Ratnakaram, Y. C.

    2018-04-01

    Ho3+ doped zinc fluorophosphate (ZFP) glasses with molar chemical compositions, (60-x) NH4H2PO4+20ZnO+10BaF2+10NaF+xHo2O3 (where x = 0.1, 0.3, 0.5, 1.0 and 1.5 mol%) were prepared by melt quenching technique. These glasses were characterized through physical, structural, optical, excitation, luminescence and decay curve analysis. From the absorption spectra, spectral intensities (fexp and fcal), Judd-Ofelt intensity parameters (Ω2, Ω4 and Ω6), radiative transition probabilities (AT), radiative lifetimes (τR) and branching ratios (βR) were evaluated for all Ho3+ doped ZFP glass matrices. From the photoluminescence spectra, peak stimulated emission cross-sections (σP) were calculated for all Ho3+ doped ZFP glasses. The Ho3+ doped ZFP glasses show strong green emission at 545 nm and red emission at 656 nm under excitation, 450 nm. The measured lifetimes (τmeas) of (5S2)5F4 level of Ho3+ doped ZFP glasses were obtained from decay profiles. The CIE color coordinates of Ho3+ doped ZFP glasses were calculated from emission spectra and 1.0 mol% of Ho3+ doped ZFP glass matrix gives green emission. Hence, these results confirm that the Ho3+ doped ZFP glasses could be considered as a promising candidate for visible green laser applications.

  8. Downregulation of Heme Oxygenase 1 (HO-1) Activity in Hematopoietic Cells Enhances Their Engraftment After Transplantation.

    PubMed

    Adamiak, Mateusz; Moore, Joseph B; Zhao, John; Abdelbaset-Ismail, Ahmed; Grubczak, Kamil; Rzeszotek, Sylwia; Wysoczynski, Marcin; Ratajczak, Mariusz Z

    2016-01-01

    Heme oxygenase 1 (HO-1) is an inducible stress-response enzyme that not only catalyzes the degradation of heme (e.g., released from erythrocytes) but also has an important function in various physiological and pathophysiological states associated with cellular stress, such as ischemic/reperfusion injury. HO-1 has a well-documented anti-inflammatory potential, and HO-1 has been reported to have a negative effect on adhesion and migration of neutrophils in acute inflammation in a model of peritonitis. This finding is supported by our recent observation that hematopoietic stem progenitor cells (HSPCs) from HO-1 KO mice are easy mobilizers, since they respond better to peripheral blood chemotactic gradients than wild-type littermates. Based on these findings, we hypothesized that transient inhibition of HO-1 by nontoxic small-molecule inhibitors would enhance migration of HSPCs in response to bone marrow chemoattractants and thereby facilitate their homing. To directly address this issue, we generated several human hematopoietic cell lines in which HO-1 was upregulated or downregulated. We also exposed murine and human BM-derived cells to small-molecule activators and inhibitors of HO-1. Our results indicate that HO-1 is an inhibitor of hematopoietic cell migration in response to crucial BM homing chemoattractants such as stromal-derived factor 1 (SDF-1) and sphingosine-1-phosphate (S1P). Most importantly, our in vitro and in vivo animal experiments demonstrate for the first time that transiently inhibiting HO-1 activity in HSPCs by small-molecule inhibitors improves HSPC engraftment. We propose that this simple and inexpensive strategy could be employed in the clinical setting to improve engraftment of HSPCs, particularly in those situations in which the number of HSPCs available for transplant is limited (e.g., when transplanting umbilical cord blood).

  9. Analysis of emission spectra of Ho{sup 3+}:LFBCd glasses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Naresh, V., E-mail: varna.naresh@gmail.com; Buddhudu, S., E-mail: varna.naresh@gmail.com

    2014-04-24

    In the present paper, we report on the absorption and emission properties of (0.1-1.5 mol %) Ho{sup 3+} doped LFBCd (Li{sub 2}O{sub −}LiF{sub −}B{sub 2}O{sub 3−}CdO) glasses prepared via melt quenching method. On exciting these glasses at (λ{sub exci}) = 452 nm, two emissions at 556 nm ({sup 5}S{sub 2}→{sup 5}I{sub 8}; Green), 655 nm ({sup 5}F{sub 5}→{sup 5}I{sub 8}; Red) have been obtained. Upon exciting these glasses with a 980 nm diode laser, NIR emissions at 1195 nm ({sup 5}I{sub 6}→{sup 5}I{sub 8}), 1951 nm ({sup 5}I{sub 7}→{sup 5}I{sub 8}) have been measured for 1 mol % Ho{sup 3+}:LFBCdmore » glass. For higher concentration beyond 1.0 mol %, emission quenching of Ho{sup 3+} glass has been noticed and which has successfully been explained in terms of an energy level diagram. From absorption cross-section data, stimulated emission cross-section has been evaluated by applying McCumber's theory and further cross-sectional gain has also been computed for the emissions at 1195 nm (∼1.20 μm) and 1951 nm (∼2.0 μm) of 1 mol % Ho{sup 3+}:LFBCd glass.« less

  10. Ho3+ doped fluoroaluminate glass fibers for 2.9 µm lasing

    NASA Astrophysics Data System (ADS)

    Jia, S. J.; Jia, Z. X.; Yao, C. F.; Wang, S. B.; Jiang, H. W.; Zhang, L.; Feng, Y.; Qin, G. S.; Ohishi, Y.; Qin, W. P.

    2018-01-01

    Ho3+ doped fluoroaluminate glass fibers based on chemically durable AlF3-BaF2-YF3-PbF2-MgF2-CaF2 glasses are fabricated by using a rod-in-tube method. By using an 84 cm long Ho3+-doped fluoroaluminate glass fiber as the gain medium and a 1120 nm fiber laser as the pump source, lasing at 2868 nm is obtained, the maximum unsaturated power is about 57 mW for a pump power of 1224 mW, and the corresponding slope efficiency is ~5.1%. The effect of the fiber length on lasing at 2868 nm is also investigated. Our results show that Ho3+-doped fluoroaluminate glass fibers are promising gain media for 2.9 µm laser applications.

  11. Ground state of Ho atoms on Pt(111) metal surfaces: Implications for magnetism

    NASA Astrophysics Data System (ADS)

    Karbowiak, M.; Rudowicz, C.

    2016-05-01

    We investigated the ground state of Ho atoms adsorbed on the Pt(111) surface, for which conflicting results exist. The density functional theory (DFT) calculations yielded the Ho ground state as | Jz=±8 > . Interpretation of x-ray absorption spectroscopy and x-ray magnetic circular dichroism spectra and the magnetization curves indicated the ground state as | Jz=±6 > . Superposition model is employed to predict the crystal-field (CF) parameters based on the structural data for the system Ho/Pt(111) obtained from the DFT modeling. Simultaneous diagonalization of the free-ion (HFI) and the trigonal CF Hamiltonian (HCF) within the whole configuration 4 f10 of H o3 + ion was performed. The role of the trigonal CF terms, neglected in the pure uniaxial CF model used previously for interpretation of experimental spectra, is found significant, whereas the sixth-rank CF terms may be neglected in agreement with the DFT predictions. The results provide substantial support for the experimental designation of the | Jz=±6 > ground state, albeit with subtle difference due to admixture of other | Jz> states, but run against the DFT-based designation of the | Jz=±8 > ground state. A subtle splitting of the ground energy level with the state (predominantly), | Jz=±6 > is predicted. This paper provides better insight into the single-ion magnetic behavior of the Ho/Pt(111) system by helping to resolve the controversy concerning the Ho ground state. Experimental techniques with greater resolution powers are suggested for direct confirmation of this splitting and C3 v symmetry experienced by the Ho atom.

  12. Sensitizing effect of Ho3+ on the Er3+: 2.7 μm-emission in fluoride glass

    NASA Astrophysics Data System (ADS)

    Huang, Feifei; Li, Xia; Liu, Xueqiang; Zhang, Junjie; Hu, Lili; Chen, Danping

    2014-03-01

    The fluorescence properties of 2.7 μm emission and energy transfer mechanism of Ho3+/Er3+ co-doped fluoride glass (ZBYA) have been investigated in the present paper. Ho3+ strengthens the Er3+: 2.7 μm emission in the ZBYA glasses due to the energy transfer from Er3+ to Ho3+, while the 1.5 μm emission decreases dramatically. The optimized concentration ratio of Er3+ to Ho3+ is found to be 1:1 in our glass system. The absorption and emission spectra are tested and the sample possesses large emission cross section (16.5 × 10-21 cm2) around 2.7 μm along with larger radiative transition probability (25.11 S-1) on the basis of Judd-Ofelt and Fuchtbauer-Ladenburg theories. Additionally, the energy transfer microparameters are calculated using Förster-Dexter theory and the result shows the energy transfer coefficient of Er3+:4I13/2 → Ho3+:5I7 is 24 times larger than that of Er3+:4I11/2 → Ho3+:5I6. Our results show that Er3+: 2.7 μm emission can be sensitized by Ho3+ efficiently, and this Er3+/Ho3+-codoped fluoride glasses might have potential application in mid-infrared lasers.

  13. Antiferromagnetic order and the structural order-disorder transition in the Cd6Ho quasicrystal approximant

    NASA Astrophysics Data System (ADS)

    Kreyssig, Andreas; Beutier, Guillaume; Hiroto, Takanobu; Kim, Min Gyu; Tucker, Gregory S.; de Boissieu, Marc; Tamura, Ryuji; Goldman, Alan I.

    2013-09-01

    It has generally been accepted that the orientational ordering of the Cd4 tetrahedron within the Cd6 R quasicrystal approximants is kinetically inhibited for R = Ho, Er, Tm and Lu by steric constraints. Our high-resolution X-ray scattering measurements of the Cd6Ho quasicrystal approximant, however, reveal an abrupt (first-order) transition to a monoclinic structure below T S = 178 K for samples that have 'aged' at room temperature for approximately one year, reopening this question. Using X-ray resonant magnetic scattering at the Ho L 3-edge we have elucidated the nature of the antiferromagnetic ordering below T N = 8.5 K in Cd6Ho. The magnetic Bragg peaks are found at the charge forbidden H + K + L = 2n + 1 positions, referenced to the high-temperature body-centred cubic structure. In general terms, this corresponds to antiferromagnetic arrangements of the Ho moments on adjacent clusters in the unit cell as previously found for Cd6Tb.

  14. Directly diode-pumped high-energy Ho:YAG oscillator.

    PubMed

    Lamrini, Samir; Koopmann, Philipp; Schäfer, Michael; Scholle, Karsten; Fuhrberg, Peter

    2012-02-15

    We report on the high-energy laser operation of an Ho:YAG oscillator resonantly pumped by a GaSb-based laser diode stack at 1.9 μm. The output energy was extracted from a compact plano-concave acousto-optically Q-switched resonator optimized for low repetition rates. Operating at 100 Hz, pulse energies exceeding 30 mJ at a wavelength of 2.09 μm were obtained. The corresponding pulse duration at the highest pump power was 100 ns, leading to a maximum peak power above 300 kW. Different pulse repetition rates and output coupling transmissions of the Ho:YAG resonator were studied. In addition, intracavity laser-induced damage threshold measurements are discussed.

  15. Ultrashort pulse CPA-free Ho:YLF linear amplifier

    NASA Astrophysics Data System (ADS)

    Hinkelmann, Moritz; Wandt, Dieter; Morgner, Uwe; Neumann, Jörg; Kracht, Dietmar

    2018-02-01

    We present CPA-free linear amplification of 6:3 ps pulses in Ho:YLF crystals up to 100 μJ pulse energy at 10 kHz repetition rate. The seed pulses at a wavelength of 2:05 μm are provided by a Ho-based all-fiber system consisting of a soliton oscillator and a subsequent pre-amplifier followed by a free-space AOM as pulse-picker. Considering the achieved pulse peak power at MW-level, this system is a powerful tool for efficient pumping of parametric amplifiers addressing the highly demanded mid-IR spectral region. In detailed numerical simulations we verified our experimental results and discuss scaling options for pulse duration and energy.

  16. Effect of hemin, baicalein and heme oxygenase-1 (HO-1) enzyme activity inhibitors on Cd-induced accumulation of HO-1, HSPs and aggresome-like structures in Xenopus kidney epithelial cells.

    PubMed

    Campbell, James H; Heikkila, John J

    2018-04-23

    Cadmium is a highly toxic environmental pollutant that can cause many adverse effects including cancer, neurological disease and kidney damage. Aquatic amphibians are particularly susceptible to this toxicant as it was shown to cause developmental abnormalities and genotoxic effects. In mammalian cells, the accumulation of heme oxygenase-1 (HO-1), which catalyzes the breakdown of heme into CO, free iron and biliverdin, was reported to protect cells against potentially lethal concentrations of CdCl 2 . In the present study, CdCl 2 treatment of A6 kidney epithelial cells, derived from the frog, Xenopus laevis, induced the accumulation of HO-1, heat shock protein 70 (HSP70) and HSP30 as well as an increase in the production of aggregated protein and aggresome-like structures. Treatment of cells with inhibitors of HO-1 enzyme activity, tin protoporphyrin (SnPP) and zinc protoporphyrin (ZnPP), enhanced CdCl 2 -induced actin cytoskeletal disorganization and the accumulation of HO-1, HSP70, aggregated protein and aggresome-like structures. Treatment of cells with hemin and baicalein, which were previously shown to provide cytoprotection against various stresses, induced HO-1 accumulation in a concentration-dependent manner. Also, treatment of cells with hemin and baicalein suppressed CdCl 2 -induced actin dysregulation and the accumulation of aggregated protein and aggresome-like structures. This cytoprotective effect was inhibited by SnPP. These results suggest that HO-1-mediated protection against CdCl 2 toxicity includes the maintenance of actin cytoskeletal and microtubular structure and the suppression of aggregated protein and aggresome-like structures. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Family of defect-dicubane Ni4Ln2 (Ln = Gd, Tb, Dy, Ho) and Ni4Y2 complexes: rare Tb(III) and Ho(III) examples showing SMM behavior.

    PubMed

    Zhao, Lang; Wu, Jianfeng; Ke, Hongshan; Tang, Jinkui

    2014-04-07

    Reactions of Ln(III) perchlorate (Ln = Gd, Tb, Dy, and Ho), NiCl2·6H2O, and a polydentate Schiff base resulted in the assembly of novel isostructural hexanuclear Ni4Ln2 complexes [Ln = Gd (1), Tb (2), Dy (3), Ho (4)] with an unprecedented 3d-4f metal topology consisting of two defect-dicubane units. The corresponding Ni4Y2 (5) complex containing diamagnetic Y(III) atoms was also isolated to assist the magnetic studies. Interestingly, complexes 2 and 3 exhibit SMM characteristics and 4 shows slow relaxation of the magnetization. The absence of frequency-dependent in-phase and out-of-phase signals for the Ni-Y species suggests that the Ln ions' contribution to the slow relaxation must be effectual as previously observed in other Ni-Dy samples. However, the observation of χ″ signals with zero dc field for the Ni-Tb and Ni-Ho derivatives is notable. Indeed, this is the first time that such a behavior is observed in the Ni-Tb and Ni-Ho complexes.

  18. Heterogeneous reaction of HO2 with airborne TiO2 particles and its implication for climate change mitigation strategies

    NASA Astrophysics Data System (ADS)

    Moon, Daniel R.; Taverna, Giorgio S.; Anduix-Canto, Clara; Ingham, Trevor; Chipperfield, Martyn P.; Seakins, Paul W.; Baeza-Romero, Maria-Teresa; Heard, Dwayne E.

    2018-01-01

    One geoengineering mitigation strategy for global temperature rises resulting from the increased concentrations of greenhouse gases is to inject particles into the stratosphere to scatter solar radiation back to space, with TiO2 particles emerging as a possible candidate. Uptake coefficients of HO2, γ(HO2), onto sub-micrometre TiO2 particles were measured at room temperature and different relative humidities (RHs) using an atmospheric pressure aerosol flow tube coupled to a sensitive HO2 detector. Values of γ(HO2) increased from 0.021 ± 0.001 to 0.036 ± 0.007 as the RH was increased from 11 to 66 %, and the increase in γ(HO2) correlated with the number of monolayers of water surrounding the TiO2 particles. The impact of the uptake of HO2 onto TiO2 particles on stratospheric concentrations of HO2 and O3 was simulated using the TOMCAT three-dimensional chemical transport model. The model showed that, when injecting the amount of TiO2 required to achieve the same cooling effect as the Mt Pinatubo eruption, heterogeneous reactions between HO2 and TiO2 would have a negligible effect on stratospheric concentrations of HO2 and O3.

  19. 36 W Q-switched Ho:YAG laser at 2097 nm pumped by a Tm fiber laser: evaluation of different Ho3+ doping concentrations

    NASA Astrophysics Data System (ADS)

    Antipov, O. L.; Eranov, I. D.; Kositsyn, R. I.

    2017-01-01

    A laser oscillator based on Ho:YAG crystal pumped by a Tm fiber laser with an acousto-optical Q-switch was optimized for maximum output power and pulse-to-pulse stability. Stable operation at 2097 nm in Q-switched mode is demonstrated, with pulse repetition rates from 10 to 30 kHz, and output power of 36 W (at 55 W of pump power at 1908 nm) in the good quality beam. The influence of Ho ion up-conversion and thermal lensing on the oscillation efficiency is discussed.

  20. Development of flashlamp-pumped Q-switched Ho:Tm:Cr:YAG lasers for mid-infrared LIDAR application

    NASA Technical Reports Server (NTRS)

    Choi, Young S.; Kim, Kyong H.; Whitney, Donald A.; Hess, Robert V.; Barnes, Norman P.; Bair, Clayton H.; Brockman, Philip

    1989-01-01

    A flashlamp-pumped 2.1 micron Ho:Tm:Cr:YAG laser was studied for both normal mode and Q-switched operations under a wide variety of experimental conditions in order to optimize performance. Laser output energy, slope efficiency, threshold and pulselength were determined as a function of operating temperature, output mirror reflectivity, input electrical energy and Q-switch opening time. The measured normal-mode laser thresholds of a Ho(3+) (0.45 atomic percent):Tm(3+) (2.5 atomic percent):Cr(3+) (0.8 atomic percent):YAG crystal ranged form 26 to 50 J between 120 and 200 K with slope efficiencies up to 0.36 percent with a 60 percent reflective output mirror. Under Q-switched operation the slope efficiency was 90 percent of the normal-mode result. Development of solid state lasers with Ho(3+), Tm(3+) and/or Er(3+) doped crystals has been pursued by NASA for eye-dafe mid-infrared LIDAR (light detection and ranging) application. As a part of the project, the authors have been working on evaluating Ho(3+):Tm(3+):Cr(3+):YAG crystals for normal-mode and Q-switched 2.1 micron laser operations in order to determine an optimum Tm(3+) concentration under flashlamp pumping conditions. Lasing properties of the Ho(3+) in the mid-infrared region have been studied by many research groups since the early 1960's. However, the technology of those lasers is still premature for lidar application. In order to overcome the inefficiency related to narrow absorption bands of the Ho(3+), Tm(3+) and Er(3+), the erbium has been replaced by chromium. The improvement in flashlamp-pumped Ho(3+) laser efficiency has been demonstrated recently by several research groups by utilizing the broad absorption spectrum of Cr(3+) which covers the flashlamp's emission spectrum. Efficient energy transfer to the Tm(3+) and then the Ho(3+) occurs subsequently. It is known that high Tm(3+) concentration and low Ho(3+) concentration are preferred to achieve a quantum efficiency approaching two and to avoid

  1. The reactions of HO2 with CO and NO and the reaction of O(1D) with H2O

    NASA Technical Reports Server (NTRS)

    Simonaitis, R.; Heicklen, J.

    1973-01-01

    HO2 radicals were generated by the photolysis of N2O at 2139 A in the presence of excess H2O or H2 and smaller amounts of CO and O2. The O(1D) atoms produced from the photolysis of N2O to give HO radicals or H2 to give HO + H. With H2O two HO radicals are produced for each O(1D) removed low pressures (i.e. approximately 20 torr H2O), but the HO yield drops as the pressure is raised. This drop is attributed to the insertion reaction: O(1D) + H2O + M yields H2O2 +M. The HO radicals generated can react with either CO or H2 to produce H atoms which then add to O2 to produce HO2. Two reactions are given for the reactions of the HO radicals, in the absence of NO.

  2. Single Longitudinal Mode, High Repetition Rate, Q-switched Ho:YLF Laser for Remote Sensing

    NASA Technical Reports Server (NTRS)

    Bai, Yingxin; Yu, Jirong; Petzar, Paul; Petros, M.; Chen, Songsheng; Trieu, Bo; Lee, Nyung; Singh, U.

    2009-01-01

    Ho:YLF/LuLiF lasers have specific applications for remote sensing such as wind-speed measurement and carbon dioxide (CO2) concentration measurement in the atmosphere because the operating wavelength (around 2 m) is located in the eye-safe range and can be tuned to the characteristic lines of CO2 absorption and there is strong backward scattering signal from aerosol (Mie scattering). Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of with a repetition rate of 5 Hz and pulse energy of 75 mJ [1]. For highly precise CO2 measurements with coherent detection technique, a laser with high repetition rate is required to averaging out the speckle effect [2]. In addition, laser efficiency is critically important for the air/space borne lidar applications, because of the limited power supply. A diode pumped Ho:Tm:YLF laser is difficult to efficiently operate in high repetition rate due to the large heat loading and up-conversion. However, a Tm:fiber laser pumped Ho:YLF laser with low heat loading can be operated at high repetition rates efficiently [3]. No matter whether wind-speed or carbon dioxide (CO2) concentration measurement is the goal, a Ho:YLF/LuLiF laser as the transmitter should operate in a single longitudinal mode. Injection seeding is a valid technique for a Q-switched laser to obtain single longitudinal mode operation. In this paper, we will report the new results for a single longitudinal mode, high repetition rate, Q-switched Ho:YLF laser. In order to avoid spectral hole burning and make injection seeding easier, a four mirror ring cavity is designed for single longitudinal mode, high repetition rate Q-switched Ho:YLF laser. The ramp-fire technique is chosen for injection seeding.

  3. Tropospheric OH and HO2 radicals: field measurements and model comparisons.

    PubMed

    Stone, Daniel; Whalley, Lisa K; Heard, Dwayne E

    2012-10-07

    The hydroxyl radical, OH, initiates the removal of the majority of trace gases in the atmosphere, and together with the closely coupled species, the hydroperoxy radical, HO(2), is intimately involved in the oxidation chemistry of the atmosphere. This critical review discusses field measurements of local concentrations of OH and HO(2) radicals in the troposphere, and in particular the comparisons that have been made with numerical model calculations containing a detailed chemical mechanism. The level of agreement between field measurements of OH and HO(2) concentrations and model calculations for a given location provides an indication of the degree of understanding of the underlying oxidation chemistry. We review the measurement-model comparisons for a range of different environments sampled from the ground and from aircraft, including the marine boundary layer, continental low-NO(x) regions influenced by biogenic emissions, the polluted urban boundary layer, and polar regions. Although good agreement is found for some environments, there are significant discrepancies which remain unexplained, a notable example being unpolluted, forested regions. OH and HO(2) radicals are difficult species to measure in the troposphere, and we also review changes in detection methodology, quality assurance procedures such as instrument intercomparisons, and potential interferences.

  4. Potential energy surface and quantum dynamics study of rovibrational states for HO(3) (X (2)A'').

    PubMed

    Braams, Bastiaan J; Yu, Hua-Gen

    2008-06-07

    An analytic potential energy surface has been constructed by fitting to about 28 thousand energy points for the electronic ground-state (X (2)A'') of HO(3). The energy points are calculated using a hybrid density functional HCTH and a large basis set aug-cc-pVTZ, i.e., a HCTH/aug-cc-pVTZ density functional theory (DFT) method. The DFT calculations show that the trans-HO(3) isomer is the global minimum with a potential well depth of 9.94 kcal mol(-1) with respect to the OH + O(2) asymptote. The equilibrium geometry of the cis-HO(3) conformer is located 1.08 kcal mol(-1) above that of the trans-HO(3) one with an isomerization barrier of 2.41 kcal mol(-1) from trans- to cis-HO(3). By using this surface, a rigorous quantum dynamics (QD) study has been carried out for computing the rovibrational energy levels of HO(3). The calculated results determine a dissociation energy of 6.15 kcal mol(-1), which is in excellent agreement with the experimental value of Lester et al. [J. Phys. Chem. A, 2007, 111, 4727.].

  5. Density-functional study of the structures and properties of holmium-doped silicon clusters HoSi n (n = 3-9) and their anions.

    PubMed

    Hou, Liyuan; Yang, Jucai; Liu, Yuming

    2017-04-01

    The structures and properties of Ho-doped Si clusters, including their adiabatic electron affinities (AEAs), simulated photoelectron spectra (PESs), stabilities, magnetic moments, and charge-transfer characteristics, were systematically investigated using four density-functional methods. The results show that the double-hybrid functional (which includes an MP2 correlation component) can accurately predict the ground-state structure and properties of Ho-doped Si clusters. The ground-state structures of HoSi n (n = 3-9) are sextuplet electronic states. The structures of these Ho-doped Si clusters (aside from HoSi 7 ) are substitutional. The ground-state structures of HoSi n - are quintuplet electronic states. Their predicted AEAs are in excellent agreement with the experimental ones. The mean absolute error in the theoretical AEAs of HoSi n (n = 4-9) is only 0.04 eV. The simulated PESs for HoSi n - (n = 5-9) are in good agreement with the experimental PESs. Based on its simulated PES and theoretical AEA, we reassigned the experimental PES of HoSi 4 - and obtained an experimental AEA of 2.2 ± 0.1 eV. The dissociation energies of Ho from HoSi n and HoSi n - (n = 3-9) were evaluated to test the relative stabilities of the clusters. HOMO-LUMO gap analysis indicated that doping the Si clusters with the rare-earth metal atom significantly increases their photochemical reactivity. Natural population analysis showed that the magnetic moments of HoSi n (n = 3-9) and their anions derive mainly from the Ho atom. It was also found that the magnetic moments of Ho in the HoSi n clusters are larger than the magnetic moment of an isolated Ho atom.

  6. The reactions of SO3 with HO2 radical and H2O...HO2 radical complex. Theoretical study on the atmospheric formation of HSO5 and H2SO4.

    PubMed

    Gonzalez, Javier; Torrent-Sucarrat, Miquel; Anglada, Josep M

    2010-03-07

    The influence of a single water molecule on the gas-phase reactivity of the HO(2) radical has been investigated by studying the reactions of SO(3) with the HO(2) radical and with the H(2)O...HO(2) radical complex. The naked reaction leads to the formation of the HSO(5) radical, with a computed binding energy of 13.81 kcal mol(-1). The reaction with the H(2)O...HO(2) radical complex can give two different products, namely (a) HSO(5) + H(2)O, which has a binding energy that is computed to be 4.76 kcal mol(-1) more stable than the SO(3) + H(2)O...HO(2) reactants (Delta(E + ZPE) at 0K) and an estimated branching ratio of about 34% at 298K and (b) sulfuric acid and the hydroperoxyl radical, which is computed to be 10.51 kcal mol(-1) below the energy of the reactants (Delta(E + ZPE) at 0K), with an estimated branching ratio of about 66% at 298K. The fact that one of the products is H(2)SO(4) may have relevance in the chemistry of the atmosphere. Interestingly, the water molecule acts as a catalyst, [as it occurs in (a)] or as a reactant [as it occurs in (b)]. For a sake of completeness we have also calculated the anharmonic vibrational frequencies for HO(2), HSO(5), the HSO(5)...H(2)O hydrogen bonded complex, H(2)SO(4), and two H(2)SO(4)...H(2)O complexes, in order to help with the possible experimental identification of some of these species.

  7. Adenovirus-delivered GFP-HO-1C[INCREMENT]23 attenuates blood-spinal cord barrier permeability after rat spinal cord contusion.

    PubMed

    Chang, Sheng; Bi, Yunlong; Meng, Xiangwei; Qu, Lin; Cao, Yang

    2018-03-21

    The blood-spinal cord barrier (BSCB) plays a key role in maintaining the microenvironment and is primarily composed of tight junction proteins and nonfenestrated capillary endothelial cells. After injury, BSCB damage results in increasing capillary permeability and release of inflammatory factors. Recent studies have reported that haem oxygenase-1 (HO-1) fragments lacking 23 amino acids at the C-terminus (HO-1C[INCREMENT]23) exert novel anti-inflammatory and antioxidative effects in vitro. However, no study has identified the role of HO-1C[INCREMENT]23 in vivo. We aimed to investigate the protective effects of HO-1C[INCREMENT]23 on the BSCB after spinal cord injury (SCI) in a rat model. Here, adenoviral HO-1C[INCREMENT]23 (Ad-GFP-HO-1C[INCREMENT]23) was intrathecally injected into the 10th thoracic spinal cord segment (T10) 7 days before SCI. In addition, nuclear and cytoplasmic extraction and immunofluorescence staining of HO-1 were used to examine the effect of Ad-GFP-HO-1C[INCREMENT]23 on HO-1 nuclear translocation. Evan's blue staining served as an index of capillary permeability and was detected by fluorescence microscopy at 633 nm. Western blotting was also performed to detect tight junction protein expression. The Basso, Beattie and Bresnahan score was used to evaluate kinematic functional recovery through the 28th day after SCI. In this study, the Ad-GFP-HO-1C[INCREMENT]23 group showed better kinematic functional recovery after SCI than the Ad-GFP and Vehicle groups, as well as smaller reductions in TJ proteins and capillary permeability compared with those in the Ad-GFP and Vehicle groups. These findings indicated that Ad-GFP-HO-1C[INCREMENT]23 might have a potential therapeutic effect that is mediated by its protection of BSCB integrity.

  8. 7 CFR 1940.968 - Rural Economic Development Review Panel Grant (Panel Grant).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 13 2013-01-01 2013-01-01 false Rural Economic Development Review Panel Grant (Panel... of Certain Rural Development Programs § 1940.968 Rural Economic Development Review Panel Grant (Panel... associated with a State rural economic development review panel. (b) Objective. The objective of the Panel...

  9. Simultaneous, in situ measurements of OH and HO sub 2 in the stratosphere

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stimpfle, R.M.; Wennberg, P.O.; Lapson, L.B.

    1990-10-01

    Stratospheric OH and HO{sub 2} radical densities have been measured between 36 and 23 using a balloon-born, in situ instrument launched from Palestine, TX on August 25, 1989. OH is detected using the laser-induced fluorescence technique (LIF) employing a Cu-vapor-laser pumped dye laser coupled with an enclosed-flow detection chamber. HO{sub 2} is detected nearly simultaneously by adding NO to the sample flow to convert ambient HO{sub 2} to OH. Observed OH and HO{sub 2} densities ranged from 8.0 {plus minus} 2.8 {times} 10{sup 6} and 1.4 {plus minus} 0.5 {times} 10{sup 7} molec cm{sup {minus}3}, respectively, at 36 km, tomore » 1.4 {plus minus} 0.5 {times} 10{sup 6} and 3.0 {plus minus} 1.0 {times} 10{sup 6} at 23 km, where the uncertainty is {plus minus} 1{sigma}. The HO{sub 2} density exhibits a maximum in the 34-30 km region of 1.7 {plus minus} 0.6 {times} 10{sup 7}. The data were obtained over a solar zenith angle variation of 51{degree} at 36 km to 61{degree} at 23 km. O{sub 3} and H{sub 2}O densities also were measured simultaneously with separate instruments.« less

  10. Simvastatin Treatment Upregulates HO-1 in Patients with Abdominal Aortic Aneurysm but Independently of Nrf2

    PubMed Central

    Kopacz, Aleksandra; Kloska, Damian; Zagrapan, Branislav; Neumayer, Christoph; Grochot-Przeczek, Anna; Huk, Ihor; Brostjan, Christine; Dulak, Jozef

    2018-01-01

    Heme oxygenase-1 (HO-1), encoded by HMOX1 gene and regulated by Nrf2 transcription factor, is a cytoprotective enzyme. Its deficiency may exacerbate abdominal aortic aneurysm (AAA) development, which is also often associated with hyperlipidemia. Beneficial effects of statins, the broadly used antilipidemic drugs, were attributed to modulation of Nrf2/HO-1 axis. However, the effect of statins on Nrf2/HO-1 pathway in patients with AAA has not been studied yet. We analyzed AAA tissue from patients treated with simvastatin (N = 28) or without statins (N = 14). Simvastatin treatment increased HO-1 protein level in AAA, both in endothelial cells (ECs) and in smooth muscle cells (SMCs), but increased Nrf2 localization was restricted only to vasa vasorum. Nrf2 target genes HMOX1, NQO1, and GCLM expression remained unchanged in AAA. In vitro studies showed that simvastatin raises HO-1 protein level slightly in ECs and to much higher extent in SMCs, which is not related to Nrf2/ARE activation, although HMOX1 expression is upregulated by simvastatin in both cell types. In conclusion, simvastatin-induced modulation of HO-1 level in ECs and SMCs in vitro is not related to Nrf2/ARE activity. Likewise, divergent HO-1 and Nrf2 localization together with stable expression of Nrf2 target genes, including HMOX1, in AAA tissue denotes Nrf2 independency. PMID:29743974

  11. Experimental study of the interaction of HO2 radicals with soot surface.

    PubMed

    Bedjanian, Yuri; Lelièvre, Stéphane; Le Bras, Georges

    2005-01-21

    The reaction of HO2 with toluene and kerosene flame soot was studied over the temperature range 240-350 K and at P = 0.5-5 Torr of helium using a discharge flow reactor coupled to a modulated molecular beam mass spectrometer. A flat-flame burner was used for the preparation and deposition of soot samples from premixed flames of liquid fuels under well controlled and adjustable combustion conditions. The independent of temperature in the range 240-350 K value of gamma = (7.5 +/- 1.5) x 10(-2) (calculated with geometric surface area) was found for the uptake coefficient of HO2 on kerosene and toluene soot. No significant deactivation of soot surface during its reaction with HO2 was observed. Experiments on soot ageing under ambient conditions showed that the reactivity of aged soot is similar to that of freshly prepared soot samples. The results show that the HO2 + soot reaction could be a significant loss process for HOx in the urban atmosphere with a potential impact on photochemical ozone formation. In contrast this process will be negligible in the upper troposphere even in flight corridors.

  12. Interactive optical panel

    DOEpatents

    Veligdan, J.T.

    1995-10-03

    An interactive optical panel assembly includes an optical panel having a plurality of ribbon optical waveguides stacked together with opposite ends thereof defining panel first and second faces. A light source provides an image beam to the panel first face for being channeled through the waveguides and emitted from the panel second face in the form of a viewable light image. A remote device produces a response beam over a discrete selection area of the panel second face for being channeled through at least one of the waveguides toward the panel first face. A light sensor is disposed across a plurality of the waveguides for detecting the response beam therein for providing interactive capability. 10 figs.

  13. Yb3+/Ho3+ Co-Doped Apatite Upconversion Nanoparticles to Distinguish Implanted Material from Bone Tissue.

    PubMed

    Li, Xiyu; Chen, Haifeng

    2016-10-07

    The exploration of bone reconstruction with time requires the combination of a biological method and a chemical technique. Lanthanide Yb 3+ and Ho 3+ co-doped fluorapatite (FA:Yb 3+ /Ho 3+ ) and hydroxyapatite (HA:Yb 3+ /Ho 3+ ) particles with varying dopant concentrations were prepared by hydrothermal synthesis and thermal activation. Controllable green and red upconversion emissions were generated under 980 nm near-infrared excitation; the FA:Yb 3+ /Ho 3+ particles resulted in superior green luminescence, while HA:Yb 3+ /Ho 3+ dominated in red emission. The difference in the green and red emission behavior was dependent on the lattice structure and composition. Two possible lattice models were proposed for Yb 3+ /Ho 3+ co-doped HA and FA along the hydroxyl channel and fluorine channel of the apatite crystal structure. We first reported the use of the upconversion apatite particles to clearly distinguish implanted material from bone tissue on stained histological sections of harvested in vivo samples. The superposition of the tissue image and material image is a creative method to show the material-tissue distribution and interrelation. The upconversion apatite particles and image superposition method provide a novel strategy for long-term discriminable fluorescence tracking of implanted material or scaffold during bone regeneration.

  14. A test of Hořava gravity: the dark energy

    NASA Astrophysics Data System (ADS)

    Park, Mu-In

    2010-01-01

    Recently Hořava proposed a renormalizable gravity theory with higher spatial derivatives in four dimensions which reduces to Einstein gravity with a non-vanishing cosmological constant in IR but with improved UV behaviors. Here, I consider a non-trivial test of the new gravity theory in FRW universe by considering an IR modification which breaks ``softly'' the detailed balance condition in the original Hořava model. I separate the dark energy parts from the usual Einstein gravity parts in the Friedman equations and obtain the formula of the equations of state parameter. The IR modified Hořava gravity seems to be consistent with the current observational data but we need some more refined data sets to see whether the theory is really consistent with our universe. From the consistency of our theory, I obtain some constraints on the allowed values of w0 and wa in the Chevallier, Polarski, and Linder's parametrization and this may be tested in the near future, by sharpening the data sets.

  15. Transmyocardial revascularization on canine with Ho:YAG laser - an experimental study

    NASA Astrophysics Data System (ADS)

    Bao, Xiaoqing; Zhu, Jing; Zhang, Hui-Guo

    2005-07-01

    Background and Objective: To evaluate the efficiency of transmyocardial revascularization with Ho:YAG laser and find out adequate physical parameters of the laser. Materials and Methods: 10 dogs were studied. All the samples were divided into two groups: the laser group (5 dogs) and the control group (5 dogs). Acute myocardial ischemia was induced in all the samples, and transmyocardial laser revascularization (TMLR) was only done in the laser group. We compared the difference of improvement in myocardial perfusion between the two groups with single photon emission computed tomograph (SPECT) and observed the patency of the laser channels and heat injures in the tissue adjacent to the channels with light- and electro-scope. Results: After 4 weeks, the recovery of myocardial perfusion was significantly faster in the laser group than in the control group through SPECT (P<0.05). Most of the laser channels drilled with Ho:YAG laser were filled with fibrin. There were amount of microvessels and erythrocytes inside and around the channels. Only slight heat injures were seen in the tissue adjacent to the channels. Only 20-30 watts were needed in TMLR. Conclusions: Transmyocardial revascularization with Ho:YAG laser limits infarct expansion and reduces myocardial ischemia efficiently. TMLR with Ho:YAG laser can become a new technique to treat ischemic heart disease.

  16. Ultra-wideband all-fiber tunable Tm/Ho-co-doped laser at 2 μm.

    PubMed

    Xue, Guanghui; Zhang, Bin; Yin, Ke; Yang, Weiqiang; Hou, Jing

    2014-10-20

    We demonstrate an all-fiber tunable Tm/Ho-codoped laser operating in the 2 μm wavelength region. The wavelength tuning range of the Tm/Ho-codoped fiber laser (THFL) with 1-m length of Tm/Ho-codoped fiber (THDF) was from 1727 nm to 2030 nm. Efficient short wavelength operation and ultra-wide wavelength tuning range of 303 nm were both achieved. To the best of our knowledge, this is the broadest tuning range that has been reported for an all-fiber rare-earth-doped laser to date. By increasing the THDF length to 2 m, the obtainable wavelength of the THFL was further red-shifted to the range from 1768 nm to 2071 nm. The output power of the THFL was scaled up from 1810 nm to 2010 nm by using a stage of Tm/Ho-codoped fiber amplifier (THFA), which exhibited the maximum slope efficiency of 42.6% with output power of 408 mW at 1910 nm.

  17. Fluorescence investigation of Ho3+ in Yb3+ sensitized mixed-alkali bismuth gallate glasses.

    PubMed

    Lin, H; Zhang, Y Y; Pun, E Y B

    2008-12-15

    Efficient 2.0 microm infrared and visible upconversion emissions have been observed in Ho3+/Yb3+ co-doped mixed-alkali bismuth gallate (LKBBG) glasses having a maximum-phonon energy of 673 cm(-1). The Judd-Ofelt parameters Omega2, Omega4 and Omega6 of Ho3+ indicate that there is a high asymmetry and strong covalent environment in LKBBG glasses. The large absorption and emission cross-sections of Yb3+ confirm that it is a suitable sensitizer for capturing and transferring pump energy to Ho3+. The emission cross-section profile for the 5I7-->5I8 transition is derived using the reciprocity method and the peak value is 5.54 x 10(-21)cm2, which is much larger than the value in fluorozircoaluminate glasses. LKBBG glasses exhibit low maximum-phonon energy and large refractive index, and it is possible to achieve an effective 1.66 microm U-band emission of Ho3+ under 900 nm laser radiation.

  18. Optical and Physical Investigations of Lanthanum Bismuth Borate glasses doped with Ho2O3

    NASA Astrophysics Data System (ADS)

    Ramesh, P.; Jagannath, G.; Eraiah, B.; Kokila, M. K.

    2018-02-01

    Holmium doped 10La2O3-15Bi2O3-(75-x) B2O3 (Ho3+: LBB) glasses have been prepared by melt quench technique and the impact of holmium ions concentration on optical and physical properties of present glasses have been examined. Ho3+ dependent density, molar volume, refractive index, rare earth ion concentration, polaron radius, inter ionic distance, field strength and energy band gap are calculated and tabulated. Amorphous nature of the all glasses has been confirmed by XRD patterns. The room temperature (RT) Uv-Vis absorption spectrum doped with 1 mol% of Ho2O3 exhibit eight prominent bands centred at 895, 641, 537, 486, 472, 467, 451 and 416 due to transition between ground state to various excited states. The results show that, the density is increases and molar volume of the glasses is decreases with an increase in Ho2O3 concentration and consequently generate more non-bridging oxygen (NBOs) in the glass matrix. The Urbach energy is increases with holmium concentration which exemplifies the degree of disorder present in the LBB glasses. The considerable increase in field strength observed in present glasses is attributed to occurrence of strong bridge between Ho3+ and B- ions and this strong bridge is possibly due to the displacement between Ho3+ and oxygen atoms which are generated from the conversion BO3-BO4 units.

  19. Quiet Honeycomb Panels

    NASA Technical Reports Server (NTRS)

    Palumbo, Daniel L.; Klos, Jacob

    2010-01-01

    Sandwich honeycomb composite panels are lightweight and strong, and, therefore, provide a reasonable alternative to the aluminum ring frame/stringer architecture currently used for most aircraft airframes. The drawback to honeycomb panels is that they radiate noise into the aircraft cabin veil- efficiently provoking the need for additional sound treatment which adds weight and reduces the material's cost advantage. A series of honeycomb panels was made -hick incorporated different design strategies aimed at reducing the honeycomb panels' radiation efficiency while at the same time maintaining their strength. The majority of the designs were centered around the concept of creating areas of reduced stiffness in the panel by adding voids and recesses to the core. The effort culminated with a reinforced/recessed panel which had 6 dB higher transmission loss than the baseline solid core panel while maintaining comparable strength.

  20. Interactive optical panel

    DOEpatents

    Veligdan, James T.

    1995-10-03

    An interactive optical panel assembly 34 includes an optical panel 10 having a plurality of ribbon optical waveguides 12 stacked together with opposite ends thereof defining panel first and second faces 16, 18. A light source 20 provides an image beam 22 to the panel first face 16 for being channeled through the waveguides 12 and emitted from the panel second face 18 in the form of a viewable light image 24a. A remote device 38 produces a response beam 40 over a discrete selection area 36 of the panel second face 18 for being channeled through at least one of the waveguides 12 toward the panel first face 16. A light sensor 42,50 is disposed across a plurality of the waveguides 12 for detecting the response beam 40 therein for providing interactive capability.

  1. Anti-Inflammatory Effect of Angelica gigas via Heme Oxygenase (HO)-1 Expression.

    PubMed

    Cho, Joon Hyeong; Kwon, Jung Eun; Cho, Youngmi; Kim, Inhye; Kang, Se Chan

    2015-06-15

    Angelica gigas (AG) is effective against various medical conditions such as bacterial infection, inflammation, and cancer. It contains a number of coumarin compounds and the group of interest is the pyranocoumarin, which comprises decursin and decursinol angelate. This group has an effect on controlling inflammation, which is caused by excessive nitric oxide (NO) production. Heme oxygenases (HOs), particularly HO-1, play a role in regulating the production of NO. Thus, this study aimed to investigate the anti-inflammatory effects of AG by measuring HO-1 expression. Treatments with CH2Cl2 layer and Angelica gigas extract (AGE) showed the highest NO inhibition effects. Decursin, decursinol angelate, and nodakenin were isolated from the CH2Cl2 layer of AGE. Decursin also demonstrated the highest anti-oxidative effect among the coumarins. Although decursin had the best NO inhibition and anti-oxidative effects, the effects of AGE treatment far surpassed that of decursin. This is owing to the combination effect of the coumarins present within AGE, which is a solvent extract of AG. The expression of HO-1 is an effective indicator of the anti-inflammatory effects of AG. Based on the results of the coumarin compounds, HO-1 expression was found to be dose dependent and specific to decursin.

  2. Anti-Inflammatory Effect of Angelica gigas via Heme Oxygenase (HO)-1 Expression

    PubMed Central

    Cho, Joon Hyeong; Kwon, Jung Eun; Cho, Youngmi; Kim, Inhye; Kang, Se Chan

    2015-01-01

    Angelica gigas (AG) is effective against various medical conditions such as bacterial infection, inflammation, and cancer. It contains a number of coumarin compounds and the group of interest is the pyranocoumarin, which comprises decursin and decursinol angelate. This group has an effect on controlling inflammation, which is caused by excessive nitric oxide (NO) production. Heme oxygenases (HOs), particularly HO-1, play a role in regulating the production of NO. Thus, this study aimed to investigate the anti-inflammatory effects of AG by measuring HO-1 expression. Treatments with CH2Cl2 layer and Angelica gigas extract (AGE) showed the highest NO inhibition effects. Decursin, decursinol angelate, and nodakenin were isolated from the CH2Cl2 layer of AGE. Decursin also demonstrated the highest anti-oxidative effect among the coumarins. Although decursin had the best NO inhibition and anti-oxidative effects, the effects of AGE treatment far surpassed that of decursin. This is owing to the combination effect of the coumarins present within AGE, which is a solvent extract of AG. The expression of HO-1 is an effective indicator of the anti-inflammatory effects of AG. Based on the results of the coumarin compounds, HO-1 expression was found to be dose dependent and specific to decursin. PMID:26083119

  3. Absolute parameters of detached binaries in the southern sky - III: HO Tel

    NASA Astrophysics Data System (ADS)

    Sürgit, D.; Erdem, A.; Engelbrecht, C. A.; van Heerden, H. P.; Manick, R.

    2017-07-01

    We present the first radial velocity analysis of the southern eclipsing binary star HO Tel, based on spectra obtained at the South African Astronomical Observatory in 2013. The orbital solution of this neglected binary gave the quite large spectroscopic mass ratio of 0.921(±0.005). The V light curve from the All Sky Automated Survey (ASAS) and Walraven five-colour (WULBV) photometric light curves (Spoelstra and Van Houten 1972) were solved simultaneously using the Wilson-Devinney code supplemented by the Monte Carlo search method. The final photometric model describes HO Tel as a detached binary star where both component stars fill about three-quarters of their Roche limiting lobes. The masses and radii were found to be 1.88(±0.04) M⊙, 2.28(±0.15) R⊙ and 1.73(±0.04) M⊙, 2.08(±0.16) R⊙ for the primary and secondary components of the system, respectively. The distance to HO Tel was calculated as 282(±30) pc, taking into account interstellar extinction. The evolution case of HO Tel was also examined. Both components of the system are evolved main-sequence stars with an age of approximately 1.1 Gy, when compared to Geneva theoretical evolution models.

  4. Hořava Gravity is Asymptotically Free in 2+1 Dimensions.

    PubMed

    Barvinsky, Andrei O; Blas, Diego; Herrero-Valea, Mario; Sibiryakov, Sergey M; Steinwachs, Christian F

    2017-11-24

    We compute the β functions of marginal couplings in projectable Hořava gravity in 2+1 spacetime dimensions. We show that the renormalization group flow has an asymptotically free fixed point in the ultraviolet (UV), establishing the theory as a UV-complete model with dynamical gravitational degrees of freedom. Therefore, this theory may serve as a toy model to study fundamental aspects of quantum gravity. Our results represent a step forward towards understanding the UV properties of realistic versions of Hořava gravity.

  5. Safety Panel Resources

    NASA Technical Reports Server (NTRS)

    Stewart, Christine E.

    2008-01-01

    The goal of this paper is to explore what resources are potentially available to safety panels and to provide some guidance on how to utilize those resources. While the examples used in this paper will concentrate on the Flight Equipment and Reliability Review Panel (FESRRP) and Extravehicular Activity (EVA) hardware that have come through that panel, as well as resources at Johnson Space Center, the paper will address how this applies to safety panels in general, and where possible cite examples for other safety panels.

  6. CO from enhanced HO activity or from CORM-2 inhibits both O2- and NO production and downregulates HO-1 expression in LPS-stimulated macrophages.

    PubMed

    Srisook, Klaokwan; Han, Shan-Shu; Choi, Hyung-Sim; Li, Mei-Hua; Ueda, Hideo; Kim, Chaekyun; Cha, Young-Nam

    2006-01-12

    Carbon monoxide (CO) arising from heme degradation, catalyzed particularly by the stress-inducible heme oxygenase-1 (HO-1), has recently been demonstrated to provide cytoprotection against cell death in macrophages stimulated with bacterial lipopolysaccharide (LPS). In the present study, we determined the effects of CO on the production of reactive oxygen species (ROS) and nitric oxide (NO) by the LPS-stimulated RAW 264.7 macrophages. In addition, effect of CO-exposure on the production of superoxide (O(2)(-)) in the phorbol myristate acetate (PMA)-stimulated PLB-985 neutrophils was determined. Production of ROS by the LPS-stimulated macrophages pretreated with 50microM [Ru(CO)(3)Cl(2)](2), a CO-releasing molecule (CORM-2), was abolished and the production of O(2)(-) by the PMA-stimulated neutrophils pretreated with the CORM-2 was decreased markedly. The CORM-2 (50microM) was not cytotoxic to both the unstimulated and LPS-stimulated macrophages when determined by employing mitochondrial reductase function test (MTT assay). In macrophages pretreated with increasing doses of CORM-2, both the LPS-derived upregulations of iNOS (NO production) and HO-1 expression (CO production) were suppressed in a dose-dependent manner. Alternatively, when the macrophages were treated with LPS and CO-donor together, the LPS-derived increase in NO production was decreased. Conversely, when the control and LPS-stimulated macrophages were treated with zinc protoporphyrin IX (ZnPP) to inhibit the HO activity blocking endogenous production of CO (basal and enhanced), macrophages died extensively. Interestingly, production of NO in the LPS-stimulated macrophages increased significantly following the ZnPP treatment. Addition of CORM-2 to the LPS-treated cells that were being treated additionally with ZnPP did not prevent the cell death. However, endogenous overproduction of CO by super-induction of HO-1 (obtained by pretreatment of macrophages with either buthionine sulfoximine or hemin

  7. TRACE-P OH and HO2 Measurements with the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) on the DC-8

    NASA Technical Reports Server (NTRS)

    Brune, William H.; Martinez-Harder, Monica; Harder, Hartwig

    2004-01-01

    The Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) measures OH and HO2 from the NASA DC-8. This instrument detects OH by laser induced fluorescence (LIF) in detection chambers at low pressure and detects HO2 by chemical conversion with NO followed by LIF detection. The demonstrated detection limit (S/N=2, 5 min.) for OH is about 0.005 pptv (1x10(exp 6)/cu cm at 2 km altitude) and for HO2 is 0.05 pptv (1x10(exp 6)/cu cm at 2 km altitude). We will use ATHOS to measure OH, HO2, and HO2/OH during TRACE- P, analyze these results by comparing them against fundamental relationships and computer models, and publish the analyses. TRACE-P HO(x), measurements will help develop a clearer picture of the atmospheric oxidation and 0 3 production that occur as Asian pollution spreads across the Pacific Ocean.

  8. Synthesis, crystal structure, optical and thermal properties of lanthanide hydrogen-polyphosphates Ln[H(PO3)4] (Ln = Tb, Dy, Ho).

    PubMed

    Förg, Katharina; Höppe, Henning A

    2015-11-28

    Lanthanide hydrogen-polyphosphates Ln[H(PO3)4] (Ln = Tb, Dy, Ho) were synthesised as colourless (Ln = Tb, Dy) and light pink (Ln = Ho) crystalline powders by reaction of Tb4O7/Dy2O3/Ho2O3 with H3PO3 at 380 °C. All compounds crystallise isotypically (P2(1)/c (no. 14), Z = 4, a(Tb) = 1368.24(4) pm, b(Tb) = 710.42(2) pm, c(Tb) = 965.79(3) pm, β(Tb) = 101.200(1)°, 3112 data, 160 parameters, wR2 = 0.062, a(Ho) = 1363.34(5) pm, b(Ho) = 709.24(3) pm, c(Ho) = 959.07(4) pm, β(Ho) = 101.055(1)°, 1607 data, 158 parameters, wR2 = 0.058). The crystal structure comprises two different infinite helical chains of corner-sharing phosphate tetrahedra. In-between these chains the lanthanide ions are located, coordinated by seven oxygen atoms belonging to four different polyphosphate chains. Vibrational, UV/Vis and fluorescence spectra of Ln[H(PO3)4] (Ln = Tb, Dy, Ho) as well as Dy[H(PO3)4]:Ln (Ln = Ce, Eu) and the magnetic and thermal behaviour of Tb[H(PO3)4] are reported.

  9. Optical properties of Mg2+, Yb3+, and Ho3+ tri-doped LiNbO3 crystals

    NASA Astrophysics Data System (ADS)

    Dai, Li; Liu, Chun-Rui; Tan, Chao; Yan, Zhe-Hua; Xu, Yu-Heng

    2017-04-01

    A series of LiNbO3 crystals tri-doped with Mg{}2+, Yb{}3+, and Ho{}3+ are grown by the conventional Czochraski technique. The concentrations of Mg{}2+, Yb{}3+, and Ho{}3+ ions in Mg:Yb:Ho:LiNbO3 crystals are measured by using an inductively coupled plasma atomic emission spectrometry. The x-ray diffraction is proposed to determine the lattice constant and analyze the internal structure of the crystal. The light-induced scattering of Mg:Yb:Ho:LiNbO3 crystal is quantitatively described via the threshold effect of incident exposure energy flux. The exposure energy ({E}{{r}}) is calculated to discuss the optical damage resistance ability. The exposure energy of Mg(7 mol):Yb:Ho:LiNbO3 crystal is 709.17 J/cm2, approximately 425 times higher than that of the Mg(1 mol):Yb:Ho:LiNbO3 crystal in magnitude. The blue, red, and very intense green bands of Mg:Yb:Ho:LiNbO3 crystal are observed under the 980-nm laser excitation to evaluate the up-conversion emission properties. The dependence of the emission intensity on pumping power indicates that the up-conversion emission is a two-photon process. The up-conversion emission mechanism is discussed in detail. This study indicates that Mg:Yb:Ho:LiNbO3 crystal can be applied to the fabrication of new multifunctional photoluminescence devices. Project supported by the National Natural Science Foundation of China (Grant No. 51301055), the Youth Science Fund of Heilongjiang Province, China (Grant No. QC2015061), the Special Funds of Harbin Innovation Talents in Science and Technology Research, China (Grant No. 2015RQQXJ045 ), and the Science Funds for the Young Innovative Talents of Harbin University of Science and Technology, China (Grant No. 201501).

  10. Adaptation of an In Situ Ground-Based Tropospheric OH/HO2 Instrument for Aircraft Use

    NASA Technical Reports Server (NTRS)

    Brune, William H.

    1997-01-01

    In-situ HO(x) (OH and HO2) measurements are an essential part of understanding the photochemistry of aircraft exhaust in the atmosphere. HO(x) affects the partitioning of nitrogen species in the NO(y) family. Its reactions are important sources and sinks for tropospheric ozone, thus providing a link between the NO(x) in aircraft exhaust and tropospheric ozone. OH mixing ratios are enhanced in aircraft wakes due to the photolysis of the HONO that is made close to the engine. Measurements of HO(x) in aircraft wakes, along with NO(x) measurements, thus provides a constraint on chemical models of the engine combustion and exhaust. The development of the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) is reported. We designed, developed, and successfully flew this instrument. It was part of the instrument complement on board the NASA DC-8 during SUCCESS, which took place in Kansas in April and May, 1996. ATHOS has a limit-of-detection for OH (S/N = 2) of 10(exp 5) OH molecules cm(exp -3) in less than 150 seconds. While this sensitivity is about 2-3 times less than the initial projections in the proposal, it is more than adequate for good measurements of OH and HO2 from the planetary boundary layer to the stratosphere. Our participation in SUCCESS was to be engineering test flights for ATHOS; however, the high-quality measurements we obtained are being used to study HO(x) photochemistry in contrails, clouds, and the clear air.

  11. Advanced concentrator panels

    NASA Technical Reports Server (NTRS)

    Bell, D. M.; Bedard, R. J., Jr.

    1981-01-01

    The prototype fabrication of a lightweight, high-quality cellular glass substrate reflective panel for use in an advanced point-focusing solar concentrator was completed. The reflective panel is a gore shaped segment of an 11-m paraboloidal dish. The overall concentrator design and the design of the reflective panels are described. prototype-specific panel design modifications are discussed and the fabrication approach and procedure outlined.

  12. In-band-pumped Ho:KLu(WO4)2 microchip laser with 84% slope efficiency.

    PubMed

    Loiko, Pavel; Serres, Josep Maria; Mateos, Xavier; Yumashev, Konstantin; Kuleshov, Nikolai; Petrov, Valentin; Griebner, Uwe; Aguiló, Magdalena; Díaz, Francesc

    2015-02-01

    We report on a continuous-wave Ho:KLu(WO4)2 (KLuW) microchip laser with a record slope efficiency of 84%, the highest value among the holmium inband-pumped lasers, delivering 201 mW output power at 2105 nm. The Ho laser operating at room temperature on the (5)I8→(5)I7 transition is in-band-pumped by a diode-pumped Tm:KLuW microchip laser at 1946 nm. Ho:KLuW laser operation at 2061 and 2079 nm is also demonstrated with a maximum slope efficiency of 79%. The microchip laser generates an almost diffraction-limited output beam with a Gaussian profile and a M2<1.1. The laser performance of the Ng-cut Ho:KLuW crystal is very similar for pump light polarizations ‖Nm and Np. The positive thermal lens plays a key role in the laser mode stabilization and proper mode-matching. The latter, together with the low quantum defect under in-band-pumping (∼0.08), is responsible for the extraordinary high slope efficiency.

  13. A Kinetic and Product Study of the Cl + HO2 Reaction

    NASA Technical Reports Server (NTRS)

    Hickson, Kevin M.; Keyser, Leon F.

    2005-01-01

    Absolute rate data and product branching ratios for the reactions Cl + HO2 to HCl + O2 (k1a) and Cl + HO2 to OH + ClO (k1b) have been measured from 226 to 336 K at a total pressure of 1 Torr of helium using the discharge flow resonance fluorescence technique coupled with infrared diode laser spectroscopy. For kinetic measurements, pseudo-first-order conditions were used with both reagents in excess in separate experiments. HO2 was produced by two methods: through the termolecular reaction of H atoms with O2 and also by the reaction of F atoms with H2O2. Cl atoms were produced by a microwave discharge of Cl2 in He. HO2 radicals were converted to OH radicals prior to detection by resonance fluorescence at 308 nm. Cl atoms were detected directly at 138 nm also by resonance fluorescence. Measurement of the consumption of HO2 in excess Cl yielded k1a and measurement of the consumption of Cl in excess HO2 yielded the total rate coefficient, k1. Values of k1a and k1 derived from kinetic experiments expressed in Arrhenius form are (1.6 +/- 0.2) x 10-11 exp[(249 +/- 34)/T] and (2.8 +/- 0.1) x 10-11 exp[(123 +/- 15)/T] cm3 molecule-1 s-1, respectively. As the expression for k1 is only weakly temperature dependent, we report a temperature-independent value of k1 = (4.5 +/- 0.4) x 10-11 cm3 molecule-1 s-1. Additionally, an Arrhenius expression for k1b can also be derived: k1b = (7.7 +/- 0.8) x 10-11 exp[-(708 +/- 29)/T] cm3 molecule-1 s-1. These expressions for k1a and k1b are valid for 226 K T 336 and 256 K T 296 K, respectively. The cited errors are at the level of a single standard deviation. For the product measurements, an excess of Cl was added to known concentrations of HO2 and the reaction was allowed to reach completion. HCl product concentrations were determined by IR absorption yielding the ratio k1a/k1 over the temperature range 236 K T 296 K. OH product concentrations were determined by resonance fluorescence giving rise to the ratio k1b/k1 over the temperature

  14. Comparative Study of the Magnetoelectric Effect in HoAl3(BO3)4 and HoGa3(BO3)4 Single Crystals

    NASA Astrophysics Data System (ADS)

    Freidman, A. L.; Dubrovskii, A. A.; Temerov, V. L.; Gudim, I. A.

    2018-03-01

    The comparative study of the magnetoelectric properties and magnetostriction of HoGa3(BO3)4 and HoAl3(BO3)4 single crystals has been carried out. The investigated compounds exhibit qualitatively similar magnetodielectric and inverse magnetoelectric ME E effects with the close absolute values, which is indicative of the weak effect of a nonmagnetic metal ion. On the contrary, the magnetostriction of the galloborate has been found to be threefold higher than that of the alumoborate. In addition, the difference between the qualitative behaviors of magnetostriction has been established: the magnetic-field dependence of magnetostriction for the alumoborate has the maximum near 70 kOe at T = 4.2 K, while the galloborate magnetostriction has no maximum and does not saturate in a field of 140 kOe.

  15. Overexpression of HO-1 assisted PM2.5-induced apoptosis failure and autophagy-related cell necrosis.

    PubMed

    Zhou, Wei; Yuan, Xiaoyan; Zhang, Li; Su, Baoting; Tian, Dongdong; Li, Yang; Zhao, Jun; Wang, Yimei; Peng, Shuangqing

    2017-11-01

    Severe smog/haze events accompanied by extremely high concentrations of airborne fine particulate matter (PM2.5) have emerged frequently in China and the potential health risks have attracted ever-growing attention. During these episodes, a surge in hospital visits for acute respiratory symptoms and respiratory diseases exacerbation has been reported to be associated with acute exposure to high-levels of particulate matters. To investigate cell fate determination and the underlying pathogenic mechanisms during severe haze episodes or smog events, we exposed human lung epithelial cells (BEAS-2B) to PM2.5 (0-400μg/mL) for 24h and found that high doses of PM2.5 caused cell necrosis and autophagy dysfunction, while co-treatment with the autophagy inhibitor 3-MA could partially reduce PM2.5-induced cell necrosis. Exposure to PM2.5 also increased the expression and mitochondrial transposition of heme oxygenase 1 (HO-1), which consequently reduced the release of cytochrome C from mitochondria to cytosol. Knockdown of HO-1 by siRNA attenuated the mitochondrial accumulation of HO-1, reversed HO-1-induced the reduction of cytochrome C release and promoted PM2.5-induced cell apoptosis. In contrast to necrosis, PM2.5-induced autophagy was independent of HO-1. In conclusion, our results demonstrate that acute exposure to high PM2.5 concentrations causes autophagy-related cell necrosis. The decrease in cytochrome C release and apoptosis by upregulation of HO-1 maybe assist PM2.5-induced autophagy-related cell necrosis. Further, this study reveals dual roles for HO-1 in PM2.5-induced cytotoxicity and presents a possible explanation for the onset of acute respiratory symptoms under extreme particulate air pollution. Copyright © 2017. Published by Elsevier Inc.

  16. HO2 measurements at atmospheric concentrations using a chemical ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Albrecht, S.; Novelli, A.; Hofzumahaus, A.; Kang, S.; Baker, Y.; Mentel, T. F.; Fuchs, H.

    2017-12-01

    Correct and precise measurements of atmospheric radical species are necessary for a better understanding of the oxidative capacity of the atmosphere. Due to the reactivity of radicals, and their consequent low concentrations, direct measurements of these species are particularly challenging and have been proven in the past to be affected by interfering species. Here we present a chemical ionization source coupled to an APi-HR-TOF-MS (Aerodyne Research Inc.), which has a limit of detection for HO2 radicals well below its atmospheric concentrations ( 1 x 108 molecules cm-3). The instrument was calibrated with a well-established and characterized HO2 calibration source in use for the laser induced fluorescence instrument in the Forschungszentrum Jülich. Within the source, a well characterized amount of HO2 radicals is produced after photolysis of water by a mercury lamp. In addition, several experiments were performed in the atmosphere simulation chamber SAPHIR at the Forschungszentrum Jülich to test for potential interferences. Measurements of HO2 radicals were concurrently detected by a laser induced fluorescence instrument allowing for the comparison of measurements within the two different and independent techniques for various atmospheric conditions regarding concentrations of O3, NOx and VOCs. Results from the intercomparison together with the calibration procedure of the instrument and laboratory characterization will be presented.

  17. Molecular cloning, characterization, and expression of an alfalfa (Medicago sativa L.) heme oxygenase-1 gene, MsHO1, which is pro-oxidants-regulated.

    PubMed

    Fu, Guang-Qing; Xu, Sheng; Xie, Yan-Jie; Han, Bin; Nie, Li; Shen, Wen-Biao; Wang, Ren

    2011-07-01

    It has been documented that plant heme oxygenase-1 (HO-1; EC 1.14.99.3) is both development- and stress-regulated, thus it plays a vital role in light signalling and stress responses. In this study, an alfalfa (Medica sativa L.) HO-1 gene MsHO1 was isolated and sequenced. It contains four exons and three introns within genomic DNA sequence and encodes a polypeptide with 283 amino acids. MsHO1 had a conserved HO signature sequence and showed high similarity to other HOs in plants, especially HO-1 isoform. The MsHO1:GFP fusion protein was localized in the chloroplast. Further biochemical activity analysis of mature MsHO1, which was expressed in Escherichia coli, showed that the Vmax was 48.78 nmol biliverdin-IXα (BV) h⁻¹ nmol⁻¹ protein with an apparent Km value for hemin of 2.33 μM, and the optimum Tm and pH were 37 °C and 7.2, respectively. Results of semi-quantitative RT-PCR and western blot showed that the expressions of MsHO1 were higher in alfalfa stems and leaves than those in germinating seeds and roots. Importantly, MsHO1 gene expression and protein level were induced significantly by some pro-oxidant compounds, including hemin and nitric oxide (NO) donor sodium nitroprusside (SNP). In conclusion, MsHO1 may play an important role in oxidative responses. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  18. An Efficient End-Pumped Ho:Tm:YLF Disk Amplifier

    NASA Technical Reports Server (NTRS)

    Yu, Ji-Rong; Petros, Mulugeta; Singh, Upendra N.; Barnes, Norman P.

    2000-01-01

    An efficient diode-pumped, room temperature Ho:Tm:YLF disk amplifier was realized by end-pump configuration. Compared to side pump configuration, about a factor three improvement in system efficiency has been demonstrated.

  19. Inside HOLMES experiment: 163Ho metallic target production for the micro-calorimeter absorber

    NASA Astrophysics Data System (ADS)

    Pizzigoni, G.; Alpert, B.; Balata, M.; Bennett, D.; Biasotti, M.; Boragno, C.; Brofferio, C.; De Gerone, M.; Dressler, R.; Faverazani, M.; Ferri, E.; Folwer, J.; Gatti, F.; Giachero, A.; Heinitz, S.; Hilton, G.; Köster, U.; Lusignoli, M.; Maino, M.; Mates, J.; Nisi, S.; Nizzolo, R.; Nucciotti, A.; Pessina, G.; Puiu, A.; Ragazzi, S.; Reintsema, C.; Ribeiro Gomes, M.; Shmidt, D.; Schumann, D.; Sisti, M.; Swetz, D.; Terranova, F.; Ullom, J.; Day, P. K.

    2016-07-01

    The main goal in the HOLMES experiment is the neutrino mass measurement using an array of 1000 micro-calorimeters with standard metallic absorber. A good isotope for such measurement is the 163Ho, those isotopes embedded in the metallic absorber will be 1011-1013. Since 163Ho is not available in nature, a dedicated process must be set up to produce the amount needed for this neutrino mass experiment. The process with the highest born-up cross-section is the neutron irradiation of Er2O3 enriched in 162Er: 162Er(n,γ)163Er →163Ho+νe, where the decay is an EC with half-life of about 75 min and the (n,γ) is about 20 barns for thermal neutron. After the neutron irradiation in the oxide powder there are several radioactive isotopes which are potentially disturbing because of the background that they cause below 5 keV. The chemical separation of holmium from the irradiation enriched Er2O3 powder is therefore mandatory and will be performed by means of ion exchange chromatography. On the end of those processes the oxide powder enriched in 162Er will have the 163Ho isotope number required. The holmium chemical state influences the end point of the EC spectrum, in order to avoid such effect it is necessary to embed in the absorber only the metallic isotope. Reduction and distillation technique allowed us to obtain a pure metallic holmium, starting from natural oxide holmium. This technique will be applied on the irradiated oxide powder to obtain the metallic 163Ho, ready to be embedded in the micro-calorimeter absorber.

  20. Assessing depression outcome in patients with moderate dementia: sensitivity of the HoNOS65+ scale.

    PubMed

    Canuto, Alessandra; Rudhard-Thomazic, Valérie; Herrmann, François R; Delaloye, Christophe; Giannakopoulos, Panteleimon; Weber, Kerstin

    2009-08-15

    To date, there is no widely accepted clinical scale to monitor the evolution of depressive symptoms in demented patients. We assessed the sensitivity to treatment of a validated French version of the Health of the Nation Outcome Scale (HoNOS) 65+ compared to five routinely used scales. Thirty elderly inpatients with ICD-10 diagnosis of dementia and depression were evaluated at admission and discharge using paired t-test. Using the Brief Psychiatric Rating Scale (BPRS) "depressive mood" item as gold standard, a receiver operating characteristic curve (ROC) analysis assessed the validity of HoNOS65+F "depressive symptoms" item score changes. Unlike Geriatric Depression Scale, Mini Mental State Examination and Activities of Daily Living scores, BPRS scores decreased and Global Assessment Functioning Scale score increased significantly from admission to discharge. Amongst HoNOS65+F items, "behavioural disturbance", "depressive symptoms", "activities of daily life" and "drug management" items showed highly significant changes between the first and last day of hospitalization. The ROC analysis revealed that changes in the HoNOS65+F "depressive symptoms" item correctly classified 93% of the cases with good sensitivity (0.95) and specificity (0.88) values. These data suggest that the HoNOS65+F "depressive symptoms" item may provide a valid assessment of the evolution of depressive symptoms in demented patients.

  1. Nd3+, Yb3+ and Ho3+ Codoped Oxyfluoride Glass Ceramics with High Efficient Green Upconversion Luminescence

    NASA Astrophysics Data System (ADS)

    Zhang, Jun-Jie; Kawamoto, Yoji; Dai, Shi-Xun; Zhang, Li-Yan; Hu, Li-Li

    2004-06-01

    New oxyfluoride glasses and glass ceramic codoped with Nd3+, Yb3+ and Ho3+ were prepared. The x-ray diffraction analysis revealed that the heat treatments of the oxyfluoride glasses could cause the precipitation of (Nd3+, Yb3+, Ho3+)-doped fluorite-type crystals. Very strong green up-conversion luminescence due to the Ho3+: (5F4, 5S2)rightarrow5I8 transition under 800-nm excitation was observed in these transparent glass ceramics. The intensity of the green up-conversion luminescence in a 1-mol% YbF3-containing glass ceramic was found to be about 120 times stronger than that in the precursor oxyfluoride glass. The reason for the highly efficient Ho3+ up-conversion luminescence in the oxyfluoride glass ceramics is discussed.

  2. PANEL LIBRARY AND EDITOR

    NASA Technical Reports Server (NTRS)

    Raible, E.

    1994-01-01

    The Panel Library and Editor is a graphical user interface (GUI) builder for the Silicon Graphics IRIS workstation family. The toolkit creates "widgets" which can be manipulated by the user. Its appearance is similar to that of the X-Windows System. The Panel Library is written in C and is used by programmers writing user-friendly mouse-driven applications for the IRIS. GUIs built using the Panel Library consist of "actuators" and "panels." Actuators are buttons, dials, sliders, or other mouse-driven symbols. Panels are groups of actuators that occupy separate windows on the IRIS workstation. The application user can alter variables in the graphics program, or fire off functions with a click on a button. The evolution of data values can be tracked with meters and strip charts, and dialog boxes with text processing can be built. Panels can be stored as icons when not in use. The Panel Editor is a program used to interactively create and test panel library interfaces in a simple and efficient way. The Panel Editor itself uses a panel library interface, so all actions are mouse driven. Extensive context-sensitive on-line help is provided. Programmers can graphically create and test the user interface without writing a single line of code. Once an interface is judged satisfactory, the Panel Editor will dump it out as a file of C code that can be used in an application. The Panel Library (v9.8) and Editor (v1.1) are written in C-Language (63%) and Scheme, a dialect of LISP, (37%) for Silicon Graphics 4D series workstations running IRIX 3.2 or higher. Approximately 10Mb of disk space is required once compiled. 1.5Mb of main memory is required to execute the panel editor. This program is available on a .25 inch streaming magnetic tape cartridge in UNIX tar format for an IRIS, and includes a copy of XScheme, the public-domain Scheme interpreter used by the Panel Editor. The Panel Library Programmer's Manual is included on the distribution media. The Panel Library and

  3. Synergistic effect of Fe2O3/Ho2O3 Co-modified 2D-titanate heterojunctions on enhanced photocatalytic degradation

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaona; Liu, Xinzhao; Lu, Dingze; Wu, Pei; Yan, Qiuyang; Liu, Min; Fang, Pengfei

    2017-01-01

    TiO2-based nanosheets (TNSs) co-modified by Fe2O3 and Ho2O3 were synthesized by one-pot hydrothermal method using Fe(NO3)3 and Ho(NO3)3 as precursors compositing with TiO2. The Fe2O3/Ho2O3-TNSs heterojunctions possessed a thickness of approximately 3-4 nm, large specific surface area of 210-310 cm2/g, with Fe2O3 and Ho2O3 nanoparticles highly dispersed over the surface of the nanosheets. The crystallization of the samples gradually increased with the amount of Fe2O3 nanoparticles, which was confirmed by the XRD, BET and Raman spectra, indicating that Ho2O3 and Fe2O3 influenced the crystallinity and structure evolution of the TNSs, besides, led to an improved the visible-light absorption. Surface photocurrent and fluorescence spectral studies revealed that the photo-generated charge carrier separation efficiency could be efficiently improved by an appropriate amount of modification. The Fe2O3/Ho2O3-TNSs exhibited synergistic effect on photocatalytic degradation of RhB as well as MO under visible light. The highest efficiency was obtained by 0.05%-Fe2O3/Ho2O3-TNSs (Fe:Ho:Ti = 0.05:1:100), which was 8.86 and 6.72 times than that of individual 1.0%-Ho2O3-TNSs (Ho:Ti = 1:100) and 0.05%-Fe2O3-TNSs (Fe:Ti = 0.05:100), respectively. The possible mechanism for enhanced visible-light-induced photocatalytic activity was proposed. Ho2O3 introduced in the photocatalysts may act as the hole capture while Fe2O3 may share the same Fermi levels with TNSs and serve as the electron capture center in the n-n-p system, which reduced the recombination rate of photo-induced electron-hole pairs.

  4. Induction of HO-1 by carbon monoxide releasing molecule-2 attenuates thrombin-induced COX-2 expression and hypertrophy in primary human cardiomyocytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chien, Peter Tzu-Yu; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan; Lin, Chih-Chung

    Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE{sub 2} release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression andmore » cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2

  5. On the role of the termolecular reactions 2O2 + H2 → 2HO2 and 2O2 + H2 → H + HO2 + O2 in formation of the first radicals in hydrogen combustion: ab initio predictions of energy barriers.

    PubMed

    Monge-Palacios, M; Rafatijo, Homayoon

    2017-01-18

    We have investigated the role of termolecular reactions in the early chemistry of hydrogen combustion. We performed molecular chemical dynamics simulations using ReaxFF in LAMMPS to identify potential initial reactions for a 1 : 4 mixture of H 2  : O 2 in the NVT ensemble at density 276.3 kg m -3 and ∼3000 K (∼4000 atm) and ∼4000 K (∼5000 atm), and then characterized the saddle points for those reactions using ab initio methods: CCSD(T) = FC/cc-pVTZ//MP2/6-31G, CCSD(T) = FULL/aug-cc-pVTZ//CCSD = FC/cc-pVTZ and CASSCF MP2/6-31G//MP2/6-31G. The main initial reaction is H 2 + O 2 → H + HO 2 , frequently occurring in the presence of a second O 2 as a third body; that is, 2O 2 + H 2 → H + HO 2 + O 2 . The second most frequent reaction is 2O 2 + H 2 → 2HO 2 . We found three saddle points on the triplet PES of these termolecular reactions: one for 2O 2 + H 2 → H + HO 2 + O 2 and two for 2O 2 + H 2 → 2HO 2 . In the latter case, one has a symmetric structure consistent with simultaneous formation of two HO 2 and the other corresponds to a bimolecular reaction between O 2 and H 2 that is "interrupted" by a second O 2 before going to completion. The classical barrier height of the symmetric saddle point for 2O 2 + H 2 → 2HO 2 is 49.8 kcal mol -1 . The barrier to H 2 + O 2 → H + HO 2 is 58.9 kcal mol -1 . The termolecular reaction will be competitive with H 2 + O 2 → H + HO 2 only at sufficiently high pressures.

  6. Magnetic moments and g-factors in odd-A Ho isotopes

    NASA Astrophysics Data System (ADS)

    Tabar, E.; Yakut, H.; Kuliev, A. A.; Quliyev, H.; Hocşgör, G.

    2017-07-01

    The ground-state magnetic moment, g K factor and quenching spin gyromagnetic ratio have been calculated using the microscopic method based on the Quasiparticle Phonon Nuclear Model (QPNM) for 155-169Ho nuclei for the first time. It is shown that the residual spin-spin interactions are responsible for the core polarization, and because of the core polarization the spin gyromagnetic factors are quenched. By considering the core polarization effects, a satisfactory agreement is obtained for the computed ground state g K factor, which gives an intrinsic contribution to the magnetic moments. In order to assess the collective contribution to the magnetic moments, the rotational gyromagnetic factors g R have been also calculated within the cranking approximation using the single particle wave function of the axially symmetric Woods-Saxon potential. For the ground-state magnetic moments of odd-proton 155-165Ho nuclei, a good description of the experimental data is obtained with an accuracy of 0.01-0.1 μ N. From systematic trends, the quenching spin gyromagnetic factor, g K factor and magnetic moment have also been theoretically predicted for 167,169Ho where there is no existing experimental data. Supported by Scientific and Technological Research Council of Turkey (TUBITAK) (115F564)

  7. Tuning into single-band red upconversion luminescence in Yb(3+)/Ho(3+) activated nano-glass-ceramics through Ce(3+) doping.

    PubMed

    Chen, Daqin; Zhou, Yang; Wan, Zhongyi; Ji, Zhenguo; Huang, Ping

    2015-03-28

    Yb(3+)/Ho(3+) activated glass ceramics containing β-YF3 nanocrystals were successfully fabricated. The green ((5)S2/(5)F4→(5)I8) upconversion emission is dominant in the glass ceramics and is about 160 times stronger than that of the precursor glass, resulting from the partition of lanthanide activators into a low-phonon-energy crystalline lattice and the subsequent low probability of multi-phonon nonradiative relaxation from the (5)S2/(5)F4 and (5)I6 states to the lower ones. Upon the introduction of Ce(3+) ions into nano-glass-ceramics, two efficient cross-relaxation processes between Ho(3+) and Ce(3+), i.e., Ho(3+):(5)S2/(5)F4 + Ce(3+):(2)F5/2→Ho(3+):(5)F5 + Ce(3+):(2)F7/2 and Ho(3+):(5)I6 + Ce(3+):(2)F5/2→Ho(3+):(5)I7 + Ce(3+):(2)F7/2, are demonstrated to greatly suppress the population of the green-emitting (5)S2/(5)F4 state and to enhance the population of the red-emitting (5)F5 one, leading to the intense single-band red UC radiation of Ho(3+).

  8. Ambient measurements of OH and HO2 radicals and the OH reactivity in and above the Borneo Rainforest

    NASA Astrophysics Data System (ADS)

    Heard, D. E.; Whalley, L. K.; Furneaux, K. L.; Edwards, P.; Commane, R.; Goddard, A.; Ingham, T.; Evans, M.

    2008-12-01

    Ground-based measurements of OH, HO2 and the OH reactivity have been made as part of the OP3 project that took place at the Bukit Atur Global Atmospheric Watch station in the Danum Valley forest conservation area in Sabah, Borneo in 2008. The project consisted of two intensive measurement periods in April and July. Aircraft measurements of OH and HO2 above the ground site were also performed and preliminary data will be presented. The OH and HO2 radicals exhibit a distinct diurnal profile, broadly following the j(O1D) profile that was measured simultaneously (daytime [OH] ~ 2 - 5 x 106 molecule cm-3, [HO2] ~ 1 - 1.5 x 108 molecule cm-3). NO, which peaked in the early morning hours ([NO] ~ 100 pptV) and isoprene, which peaked in the afternoon ([isoprene] ~ 2 - 5 ppbV) were found to influence the OH profile. Both OH and HO2 persisted into the night and were detectable even after j(O1D) had fallen to zero (nighttime [OH] ~ 2.5 x 105 molecule cm-3, [HO2] ~ 2 x 107 molecule cm-3), suggesting night-time radical sources. The OH reactivity tracked the isoprene concentration, exhibiting maximum reactivity just after midday when isoprene levels peaked. Zero dimensional models, using a variety of mechanisms, have been used to predict the [OH], [HO2] and the OH reactivity that were observed. The models, constrained with measured OH sources and sinks, are used to test the hypothesis that OH is recycled from isoprene oxidation in this low NOx environment

  9. Crystal structure, chemical expansion and phase stability of HoMnO{sub 3} at high temperature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Selbach, Sverre M., E-mail: selbach@material.ntnu.no; Nordli Lovik, Amund; Bergum, Kristin

    Anisotropic thermal and chemical expansion of hexagonal HoMnO{sub 3} was investigated by high temperature X-ray diffraction in inert (N{sub 2}) and oxidizing (air) atmospheres up to 1623 K. A second order structural phase transition directly from P6{sub 3}cm to P6{sub 3}/mmc was found at 1298{+-}4 K in N{sub 2} atmosphere, and 1318{+-}4 K in air. For the low temperature polymorph P6{sub 3}cm the contraction of the c-axis was more rapid in inert than in oxidizing atmosphere. The c-axis of the P6{sub 3}/mmc polymorph of HoMnO{sub 3} displayed anomalously high expansion above 1400 K, which is discussed in relation to chemicalmore » expansion caused by point defects. The a-axis expanded stronger in inert than oxidizing atmosphere. Anisotropic chemical and thermal expansion of the P6{sub 3}cm phase of YMnO{sub 3} in N{sub 2}, air and O{sub 2} atmospheres was found to be qualitatively similar to that of HoMnO{sub 3}. Decomposition of hexagonal HoMnO{sub 3} by two different processes occurs in oxidizing atmosphere above {approx}1200 K followed by nucleation and growth of the perovskite polymorph of HoMnO{sub 3}. A rapid, reconstructive transition from the perovskite back to the hexagonal polymorph was observed in situ at 1623 K upon reduction of the partial pressure of oxygen. A phase stability diagram of the hexagonal and orthorhombic polymorphs is proposed. Finally, distinctly non-linear electrical conductivity was observed for both HoMnO{sub 3} and YMnO{sub 3} in oxidizing atmosphere between 555 and 630 K, and shown to be associated with excess oxygen. - Graphical abstract: Chemical expansion of hexagonal HoMnO{sub 3} is observed during HTXRD in different pO{sub 2}. Oxidizing atmosphere favors the competing perovskite polymorph. Electrical conductivity anomalies related to excess oxygen are found at 550-630 K. Highlights: Black-Right-Pointing-Pointer Thermal evolution of crystal structure of HoMnO{sub 3} studied up to 1623 K in air and N{sub 2}. Black

  10. Single crystal polarized neutron diffraction study of the magnetic structure of HoFeO3.

    PubMed

    Chatterji, T; Stunault, A; Brown, P J

    2017-09-27

    Polarised neutron diffraction measurements have been made on HoFeO 3 single crystals magnetised in both the [0 0 1] and [1 0 0] directions (Pbnm setting). The polarisation dependencies of Bragg reflection intensities were measured both with a high field of [Formula: see text] T parallel to [0 0 1] at [Formula: see text] K and with the lower field [Formula: see text] T parallel to [1 0 0] at [Formula: see text] K. A Fourier projection of magnetization induced parallel to [0 0 1], made using the hk0 reflections measured in 9 T, indicates that almost all of it is due to alignment of Ho moments. Further analysis of the asymmetries of general reflections in these data showed that although, at 70 K, 9 T applied parallel to [0 0 1] hardly perturbs the antiferromagnetic order of the Fe sublattices, it induces significant antiferromagnetic order of the Ho sublattices in the [Formula: see text] plane, with the antiferromagnetic components of moment having the same order of magnitude as the induced ferromagnetic ones. Strong intensity asymmetries measured in the low temperature [Formula: see text] structure with a lower field, 0.5 T [Formula: see text] [1 0 0] allowed the variation of the ordered components of the Ho and Fe moments to be followed. Their absolute orientations, in the [Formula: see text] domain stabilised by the field were determined relative to the distorted perovskite structure. This relationship fixes the sign of the Dzyalshinski-Moriya (D-M) interaction which leads to the weak ferromagnetism. Our results indicate that the combination of strong y-axis anisotropy of the Ho moments and Ho-Fe exchange interactions breaks the centrosymmetry of the structure and could lead to ferroelectric polarization.

  11. Itinerant and localized magnetization dynamics in antiferromagnetic Ho

    DOE PAGES

    Rettig, L.; Dornes, C.; Thielemann-Kuhn, N.; ...

    2016-06-21

    Using femtosecond time-resolved resonant magnetic x-ray diffraction at the Ho L 3 absorption edge, we investigate the demagnetization dynamics in antiferromagnetically ordered metallic Ho after femtosecond optical excitation. Here, tuning the x-ray energy to the electric dipole (E1, 2p → 5d) or quadrupole (E2, 2p → 4f) transition allows us to selectively and independently study the spin dynamics of the itinerant 5d and localized 4f electronic subsystems via the suppression of the magnetic (2 1 3–τ) satellite peak. We find demagnetization time scales very similar to ferromagnetic 4f systems, suggesting that the loss of magnetic order occurs via a similarmore » spin-flip process in both cases. The simultaneous demagnetization of both subsystems demonstrates strong intra-atomic 4f–5d exchange coupling. In addition, an ultrafast lattice contraction due to the release of magneto-striction leads to a transient shift of the magnetic satellite peak.« less

  12. Panel 5: Microbiology and Immunology Panel

    PubMed Central

    Murphy, Timothy F.; Chonmaitree, Tasnee; Barenkamp, Stephen; Kyd, Jennelle; Nokso-Koivisto, Johanna; Patel, Janak A.; Heikkinen, Terho; Yamanaka, Noboru; Ogra, Pearay; Swords, W. Edward; Sih, Tania; Pettigrew, Melinda M.

    2014-01-01

    Objective The objective is to perform a comprehensive review of the literature from January 2007 through June 2011 on the virology, bacteriology, and immunology related to otitis media. Data Sources PubMed database of the National Library of Medicine. Review Methods Three subpanels with co-chairs comprising experts in the virology, bacteriology, and immunology of otitis media were formed. Each of the panels reviewed the literature in their respective fields and wrote draft reviews. The reviews were shared with all panel members, and a second draft was created. The entire panel met at the 10th International Symposium on Recent Advances in Otitis Media in June 2011 and discussed the review and refined the content further. A final draft was created, circulated, and approved by the panel. Conclusion Excellent progress has been made in the past 4 years in advancing an understanding of the microbiology and immunology of otitis media. Advances include laboratory-based basic studies, cell-based assays, work in animal models, and clinical studies. Implications for Practice The advances of the past 4 years formed the basis of a series of short-term and long-term research goals in an effort to guide the field. Accomplishing these goals will provide opportunities for the development of novel interventions, including new ways to better treat and prevent otitis media. PMID:23536533

  13. Road to Victory: Building the Ho Chi Minh Trail.

    ERIC Educational Resources Information Center

    Kenney, Marianne

    1993-01-01

    Presents a secondary school lesson on the building of the Ho Chi Minh Trail during the Vietnam War. Helps students link history and geographical skills through cooperative group learning. Includes maps, diagrams, and three student readings. (CFR)

  14. Inhibitory effect of leptin on rosiglitazone-induced differentiation of primary adipocytes prepared from TallyHO/Jng mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Ki Young; Kim, Joo Young; Sung, Yoon-Young

    2011-03-25

    Research highlights: {yields} In this study, we investigated the effects of leptin on adipocyte differentiation prepared from subcutaneous fat of TallyHo mice. {yields} Leptin inhibited the adipocytes differentiation at physiological concentration via inhibition of PPAR{gamma} expression. {yields} Inhibitors of ERK and STAT1 restored the leptin's inhibitory activity both in vitro and in vivo. -- Abstract: The effects of leptin on rosiglitazone-induced adipocyte differentiation were investigated in the primary adipocytes prepared from subcutaneous fat of TallyHO/Jng (TallyHO) mouse, a recently developed model animal for type 2 diabetes mellitus (T2DM). The treatment of leptin inhibited the rosiglitazone-induced adipocyte differentiation with a decreasedmore » expression of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) a key adipogenic transcription factor, both in mRNA and protein levels. Leptin (10 nM) was sufficient to inhibit the adipocyte differentiation, which seemed to come from increased expression of leptin receptor genes in the fat of TallyHO mice. The inhibition of adipogenesis by leptin was restored by the treatment of inhibitors for extracellular-signal-regulated kinase (ERK) (PD98059) and signal transducer and activator of transcription-1 (STAT1) (fludarabine). Furthermore, in vivo intraperitoneal administration of PD98059 and fludarabine increased the PPAR{gamma} expression in the subcutaneous fat of TallyHO mice. These data suggest that leptin could inhibit the PPAR{gamma} expression and adipocyte differentiation in its physiological concentration in TallyHO mice.« less

  15. Reinforced Honeycomb Panels

    NASA Technical Reports Server (NTRS)

    Bhat, Balakrishna T.; Akutagawa, Wesley; Wang, Taylor G.; Barber, Dan

    1989-01-01

    New honeycomb panel structure has increased strength and stiffness with little increase in weight. Some or all of walls of honeycomb cells reinforced with honeycomb panels having smaller cells, lightweight foam, or other reinforcing material. Strong, lightweight reinforced panels used in aircraft, car and truck bodies, cabinets for equipment and appliances, and buildings.

  16. Controlled synthesis, formation mechanism, and carbon oxidation properties of Ho2Cu2O5 nanoplates prepared with a coordination-complex method

    NASA Astrophysics Data System (ADS)

    Guo, Rui; You, Junhua; Han, Fei; Li, Chaoyang; Zheng, Guiyuan; Xiao, Weicheng; Liu, Xuanwen

    2017-02-01

    Ho2Cu2O5 nanoplates with perovskite structures were synthesized via a simple solution method (SSM) and a coordination-complex method (CCM) using [HoCu(3,4-pdc)2(OAc)(H2O)3]·8H2O (L = 3,4-pyridinedicarboxylic acid) as a precursor. The CCM was also performed in an N2 environment (CCMN) under various calcination conditions. The crystallization processes were characterized using X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. Ho2Cu2O5 formed through the diffusion of CuO into Ho2O3 particles. Cu2+ diffused faster than Ho3+ during this process. The initial products of CCMN (along with the thermal decomposition products) were initially laminarized in the N2 atmosphere, which prevented the growth of CuO particles and decreased the size of the Ho2Cu2O5 particles. The final Ho2Cu2O5 particles from CCMN had a nanoplate morphology with an average thickness of 75 nm. The decomposition of organic molecules and protection from N2 played important roles in determining the morphology of the resulting Ho2Cu2O5. The catalytic oxidation activity of Ho2Cu2O5 samples for carbon was characterized using a specific surface area measurement and thermogravimetric analysis, which revealed that the samples produced by CCMN had the highest catalytic activity.

  17. Magnetic properties of epitaxial hexagonal HoFeO3 thin films

    NASA Astrophysics Data System (ADS)

    Wang, Xiao; Xiao, Zhuyun; Xu, Xiaoshan; Wang, Wenbin; Keavney, David; Liu, Yaohua; Cheng, X. M.

    2014-03-01

    Multiferroic materials exhibit multiple ferroic orders simultaneously and thus have great potential applications in information technology, sensing and actuation. Epitaxial hexagonal HoFeO3 (h-HFO) films are very promising candidates as multiferroic materials with room temperature ferromagnetism, because magnetic Ho3+ ions are expected to have stronger exchange interactions with Fe3+ ions than the well-studied h-LuFeO3 films. We report study of magnetic properties of epitaxial h-HFO thin films deposited using laser molecular beam epitaxy on Yttria-stabilized zirconia (YSZ) substrates. X-ray diffraction measurements confirmed the epitaxial registry and six-fold symmetry of the film. Temperature dependence of magnetization of the film measured by a Quantum Design SQUID magnetometer shows dominating paramagnetic characteristic. Element specific x-ray magnetic circular dichroism measurements performed at beamline 4-ID-C of the Advanced Photon Source show a ferromagnetic ordering of Fe and an exchange coupling between Ho3+ and Fe3+ ions. Work at BMC is supported by NSF Career award (DMR 1053854). Work at ANL is supported by US-DOE, Office of Science, BES (No. DE-AC02-06CH11357).

  18. Registration of ‘Ho 00-961’ sugarcane

    USDA-ARS?s Scientific Manuscript database

    Ho 00-961’ (Reg. No., PI) sugarcane (a complex hybrid of Saccharum officinarum L., S. spontaneum L., S. barberi Jeswiet, and S. sinense Roxb. amend. Jeswiet) was selected by the USDA-ARS Sugarcane Research Unit, and evaluated cooperatively with the Louisiana State University Agricultural Center, an...

  19. Magnetic properties and magnetocaloric effects in HoPd intermetallic

    NASA Astrophysics Data System (ADS)

    Zhao-Jun, Mo; Jun, Shen; Xin-Qiang, Gao; Yao, Liu; Jian-Feng, Wu; Bao-Gen, Shen; Ji-Rong, Sun

    2015-03-01

    A large reversible magnetocaloric effect accompanied by a second order magnetic phase transition from PM to FM is observed in the HoPd compound. Under the magnetic field change of and the refrigerant capacity RC for the compound are evaluated to be 20 J/(kg · K) and 342 J/kg, respectively. In particular, large (11.3 J/(kg · K)) and RC (142 J/kg) are achieved under a low magnetic field change of 0-2 T with no thermal hysteresis and magnetic hysteresis loss. The large reversible magnetocaloric effect (both the large -ΔSM and the high RC) indicates that HoPd is a promising material for magnetic refrigeration at low temperature. Project supported by the National Natural Science Foundation of China (Grant Nos. 51322605, 11104337, 51271192, and 11274357) and the Knowledge Innovation Project of the Chinese Academy of Sciences.

  20. Development and performance characteristics of flash lamp pumped Yb:YAG, Cr:Tm:Ho:YAG, Er:Tm:Ho:YLF laser sources and investigation of their potential biological applications

    NASA Astrophysics Data System (ADS)

    Karadimitriou, N.; Klinkenberg, B.; Papadopoulos, D. N.; Serafetinides, A. A.

    2007-07-01

    Laser ablation for the formation of apodized patterns on intraocular lenses, as an alternative of the conventional injection molding, has been proved to be a very promising new technique. For the precise lenses ablation, the use of suitable laser wavelength and pulse duration, resulting in a small optical penetration depth in the lens and in confinement of the energy deposition in a small volume, as well as the reduced thermal damage to the surrounding tissue, is essential. Mid-infrared laser wavelengths, at which the organic biological simulators absorption coefficient is large, meet well the above conditions. Towards the complete understanding of the intraocular lens ablation procedure and therefore the choice of the optimum laser beam characteristics for the most accurate, efficient and safe surgical application, the comparative study of various mid-infrared laser sources is of great interest. In this work we investigate the potential of the development of three different mid-infrared laser sources, namely the Yb:YAG, the Cr:Tm:Ho:YAG and the Er:Tm:Ho:YLF laser, operating at 1029 nm, 2060 nm and 2080 nm respectively and their ability in forming patterns on biomaterials. Pumping was achieved with conventional Xe flash lamps in a double elliptical pump chamber. A properly designed Pulse-Forming- Network capable of delivering energy up to 800 J, in variable lamp illumination durations is used. Several hundreds of mJoules were achieved from the Yb:YAG laser oscillator and several Joules from the Ho:YAG and Ho:YLF laser oscillators. Free running and Q-switched laser operation studies and preliminary experiments on laser and biomaterials (biopolymers and animal tissues) interactions will be reported.

  1. Line Identification of Atomic and Ionic Spectra of Holmium in the Near-UV. Part I. Spectrum of Ho I

    NASA Astrophysics Data System (ADS)

    Al-Labady, N.; Özdalgiç, B.; Er, A.; Güzelçimen, F.; Öztürk, I. K.; Kröger, S.; Kruzins, A.; Tamanis, M.; Ferber, R.; Başar, Gö.

    2017-02-01

    The Fourier Transform spectra of a Holmium hollow cathode discharge lamp have been investigated in the UV spectral range from 25,000 up to 31,530 cm-1 (317 to 400 nm). Two Ho spectra have been measured with neon and argon as buffer gases. Based on the intensity ratios from these two spectra, a distinction was made between atomic and ionic lines (ionic lines are discussed in an accompanying paper). Using the known Ho I energy levels, 71 lines could be classified as transitions of atomic Ho, 34 of which have not been published previously. Another 32 lines, which could not be classified, are listed in the literature and assigned as atomic Ho. An additional 370 spectral lines have been assigned to atomic Ho based on the signal-to-noise ratio in the two spectra measured under different discharge conditions, namely with buffer gases argon and neon, respectively. These 370 lines have not been previously listed in the literature.

  2. Lack of evidence for the presence of emerging HoBi-like viruses in North American fetal bovine serum lots.

    PubMed

    Bauermann, Fernando V; Flores, Eduardo F; Falkenberg, Shollie M; Weiblen, Rudi; Ridpath, Julia F

    2014-01-01

    The detection of an emerging pestivirus species, "HoBi-like virus," in fetal bovine serum (FBS) labeled as U.S. origin, but packaged in Europe, raised concerns that HoBi-like virus may have entered the United States. In the current study, 90 lots of FBS originating in North America (NA) were screened for pestivirus antigen and antibodies. Lots in group 1 (G1, 72 samples) and group 2 (G2, 9 samples) originated in NA and were packaged in the United States. Group 3 (G3) was composed of 9 lots collected in NA and processed in Europe. Lots in G1 were claimed negative for Bovine viral diarrhea virus (BVDV), while lots in G2 and G3 were claimed positive by the commercial processor. All lots in G1 and G2 tested negative by reverse transcription polymerase chain reaction (RT-PCR) using HoBi-like-specific primers. Two G1 lots tested positive by BVDV RT-PCR. One of these was also positive by virus isolation. All G2 lots were positive by BVDV RT-PCR. In addition, four G2 lots were VI positive while 1 lot was antigen-capture enzyme-linked immunosorbent assay (ELISA) positive. Two G3 lots were positive by HoBi-like-specific RT-PCR tests. All lots were negative for HoBi_D32/00 neutralizing antibodies. Seven lots (4 G1; 1 G2; 2 G3) had antibodies against BVDV by virus neutralization and/or antigen-capture ELISA. While there is no evidence of HoBi-like viruses in NA based on tested samples, further studies are required to validate HoBi-like virus-free status and develop means to prevent the spread of HoBi-like virus into NA.

  3. Mica Nanoparticle, STB-HO Eliminates the Human Breast Carcinoma Cells by Regulating the Interaction of Tumor with its Immune Microenvironment.

    PubMed

    Kang, Tae-Wook; Kim, Hyung-Sik; Lee, Byung-Chul; Shin, Tae-Hoon; Choi, Soon Won; Kim, Yoon-Jin; Lee, Hwa-Yong; Jung, Yeon-Kwon; Seo, Kwang-Won; Kang, Kyung-Sun

    2015-12-03

    Mica, an aluminosilicate mineral, has been proven to possess anti-tumor and immunostimulatory effects. However, its efficacy and mechanisms in treating various types of tumor are less verified and the mechanistic link between anti-tumor and immunostimulatory effects has not been elucidated. We sought to investigate the therapeutic effect of STB-HO (mica nanoparticles) against one of the most prevalent cancers, the breast cancer. STB-HO was orally administered into MCF-7 xenograft model or directly added to culture media and tumor growth was monitored. STB-HO administration exhibited significant suppressive effects on the growth of MCF-7 cells in vivo, whereas STB-HO did not affect the proliferation and apoptosis of MCF-7 cells in vitro. To address this discrepancy between in vivo and in vitro results, we investigated the effects of STB-HO treatment on the interaction of MCF-7 cells with macrophages, dendritic cells (DCs) and natural killer (NK) cells, which constitute the cellular composition of tumor microenvironment. Importantly, STB-HO not only increased the susceptibility of MCF-7 cells to immune cells, but also stimulated the immunocytes to eliminate cancer cells. In conclusion, our study highlights the possible role of STB-HO in the suppression of MCF-7 cell growth via the regulation of interactions between tumor cells and anti-tumor immune cells.

  4. Mica Nanoparticle, STB-HO Eliminates the Human Breast Carcinoma Cells by Regulating the Interaction of Tumor with its Immune Microenvironment

    PubMed Central

    Kang, Tae-Wook; Kim, Hyung-Sik; Lee, Byung-Chul; Shin, Tae-Hoon; Choi, Soon Won; Kim, Yoon-Jin; Lee, Hwa-Yong; Jung, Yeon-Kwon; Seo, Kwang-Won; Kang, Kyung-Sun

    2015-01-01

    Mica, an aluminosilicate mineral, has been proven to possess anti-tumor and immunostimulatory effects. However, its efficacy and mechanisms in treating various types of tumor are less verified and the mechanistic link between anti-tumor and immunostimulatory effects has not been elucidated. We sought to investigate the therapeutic effect of STB-HO (mica nanoparticles) against one of the most prevalent cancers, the breast cancer. STB-HO was orally administered into MCF-7 xenograft model or directly added to culture media and tumor growth was monitored. STB-HO administration exhibited significant suppressive effects on the growth of MCF-7 cells in vivo, whereas STB-HO did not affect the proliferation and apoptosis of MCF-7 cells in vitro. To address this discrepancy between in vivo and in vitro results, we investigated the effects of STB-HO treatment on the interaction of MCF-7 cells with macrophages, dendritic cells (DCs) and natural killer (NK) cells, which constitute the cellular composition of tumor microenvironment. Importantly, STB-HO not only increased the susceptibility of MCF-7 cells to immune cells, but also stimulated the immunocytes to eliminate cancer cells. In conclusion, our study highlights the possible role of STB-HO in the suppression of MCF-7 cell growth via the regulation of interactions between tumor cells and anti-tumor immune cells. PMID:26631982

  5. Solar reflection panels

    DOEpatents

    Diver, Jr., Richard B.; Grossman, James W [Albuquerque, NM; Reshetnik, Michael [Boulder, CO

    2006-07-18

    A solar collector comprising a glass mirror, and a composite panel, wherein the back of the mirror is affixed to a front surface of the composite panel. The composite panel comprises a front sheet affixed to a surface of a core material, preferably a core material comprising a honeycomb structure, and a back sheet affixed to an opposite surface of the core material. The invention may further comprise a sealing strip, preferably comprising EPDM, positioned between the glass mirror and the front surface of the composite panel. The invention also is of methods of making such solar collectors.

  6. First Spectroscopic Solutions of Two Southern Eclipsing Binaries: HO Tel and QY Tel

    NASA Astrophysics Data System (ADS)

    Sürgit, D.; Erdem, A.; Engelbrecht, C. A.; van Heerden, P.; Manick, R.

    2015-07-01

    We present preliminary results from the analysis of spectroscopic observations of two southern eclipsing binary stars, HO Tel and QY Tel. The grating spectra of these two systems were obtained at the Sutherland Station of the South African Astronomical Observatory in 2013. Radial velocities of the components were determined by the Fourier disentangling technique. Keplerian radial velocity models of HO Tel and QY Tel give their mass ratio as 0.921±0.005 and 1.089±0.007, respectively.

  7. Using transurethral Ho:YAG-laser resection to treat urethral stricture and bladder neck contracture

    NASA Astrophysics Data System (ADS)

    Bo, Juanjie; Dai, Shengguo; Huang, Xuyuan; Zhu, Jing; Zhang, Huiguo; Shi, Hongmin

    2005-07-01

    Objective: Ho:YAG laser had been used to treat the common diseases of urinary system such as bladder cancer and benign prostatic hyperplasia in our hospital. This study is to assess the efficacy and safety of transurethral Ho:YAG-laser resection to treat the urethral stricture and bladder neck contracture. Methods: From May 1997 to August 2004, 26 cases of urethral stricture and 33 cases of bladder neck contracture were treated by transurethral Ho:YAG-laser resection. These patients were followed up at regular intervals after operation. The uroflow rate of these patients was detected before and one-month after operation. The blood loss and the energy consumption of holmium-laser during the operation as well as the complications and curative effect after operation were observed. Results: The therapeutic effects were considered successful, with less bleeding and no severe complications. The Qmax of one month postoperation increased obviously than that of preoperation. Of the 59 cases, restenosis appeared in 11 cases (19%) with the symptoms of dysuria and weak urinary stream in 3-24 months respectively. Conclusions: The Ho:YAG-laser demonstrated good effect to treat the obstructive diseases of lower urinary tract such as urethral stricture and bladder neck contracture. It was safe, minimal invasive and easy to operate.

  8. Studies on structural and electrical properties of nanostructured RMnO3 (R = Gd & Ho)

    NASA Astrophysics Data System (ADS)

    Sapana, Solanki; Dhruv, Davit; Joshi, Zalak; Gadani, Keval; Rathod, K. N.; Boricha, Hetal; Shrimali, V. G.; Trivedi, R. K.; Joshi, A. D.; Pandya, D. D.; Solanki, P. S.; Shah, N. A.

    2017-05-01

    We report the results of the studies on the structural and electrical properties of multiferroic GdMnO3 and HoMnO3 materials synthesized by sol-gel route. Structural analysis of the results of X-ray diffraction (XRD) measurement shows that materials are found to be crystallized in orthorhombic and hexagonal symmetry, respectively for GdMnO3 and HoMnO3. Frequency dependent dielectric properties of nanostructured GdMnO3 and HoMnO3 were carried out using LCR meter in the frequency range of 100Hz to 2MHz at room temperature. Dielectric constant decreases with increasing frequency for both the nanostructured multiferroics which can be attributed to the dipole relaxation process. AC conductivity (σAC) has been measured for both the samples and fitted theoretically by using power law equation.

  9. Electromagnetic and Microwave Absorption Properties of the Flake-Shaped Pr-Ho-Fe Alloys in the C-Band

    NASA Astrophysics Data System (ADS)

    Luo, Jialiang; Pan, Shunkang; Qiao, Ziqiang; Cheng, Lichun; Wang, Zhenzhong; Lin, Peihao; Chang, Junqing

    2018-01-01

    The polycrystalline samples Pr x Ho2- x Fe17 ( x = 0.0, 0.1, 0.2, 0.3, 0.4) were prepared by arc melting and high-energy ball milling method. The influences of Pr substitution on phase structure, morphology, saturation magnetization and electromagnetic parameters were investigated by x-ray diffraction, scanning electron microscopy, vibrating-sample magnetometry and vector network analyzer, respectively. The results show that the particle size increased and the saturation magnetization decreased with increasing Pr content. The minimum absorption peak frequency shifted towards a lower-frequency region with increasing Pr concentration. The minimum RL of Pr0.3Ho1.7Fe17 powder was -41.03 dB at 6.88 GHz with a coating thickness of 2.0 mm. With different thickness of 1.8-2.8 mm, the minimum reflection loss (RL) of Pr0.3Ho1.7Fe17 powder was less than -20 dB in the whole C-band (4-8 GHz). The microwave-absorbing properties of the composite with different weight ratios of Pr0.3Ho1.7Fe17/Co were researched. The microwave-absorbing peaks of the composites shifted to a lower frequency with increasing Co content. The minimum RL of Pr0.3Ho1.7Fe17/Co(10%) was -42.51 dB at 4.72 GHz with a coating thickness of 2.6 mm. This suggests that the Pr-Ho-Fe will be a promising microwave absorption material in higher-gigahertz frequency, especially in the C-band.

  10. White up-conversion emission in Ho3+/Tm3+/Yb3+ tri-doped glass ceramics embedding BaF2 nanocrystals

    NASA Astrophysics Data System (ADS)

    Li, Chenxia; Xu, Shiqing; Ye, Rengguang; Deng, Degang; Hua, Youjie; Zhao, Shilong; Zhuang, Songlin

    2011-04-01

    Ho3+/Tm3+/Yb3+ tri-doped glass ceramics with white light emitting have been developed and demonstrated. Pumped by 980 nm laser diode (LD), intensive red, green and blue up-conversions (UC) were obtained. The green emission is assigned to Ho3+ ion and the blue emission is assigned to Tm3+ ion, whereas the red emission is the combination contribution of the Ho3+ and Tm3+ ions. The RGB intensities could be adjusted by tuning the rare-earth ion concentration and pump power intensity. Thus, multicolor of the luminescence, including perfect white light with CIE-X=0.329 and CIE-Y=0.342 in the 1931 CIE chromaticity diagram can be obtained in 0.15 Ho3+/0.2Tm3+/3Yb3+ tri-doped glass ceramics embedding BaF2 nanocrystals pumped by a single infrared laser diode source of 980 nm at 500 mW. The up-conversion luminescence mechanism of Yb3+ sensitize Ho3+ and Tm3+ ions and the energy transfer from Ho3+ to Tm3+ in oxy-fluoride silicate glass ceramics were analyzed.

  11. Impacts and Preferences Study for e-HO as a Holistic Learning Environment Complementary to E-Learning

    ERIC Educational Resources Information Center

    Lee, Ching-Yieh; Der Pan, Peter Jen; Liao, Ching-Jung

    2011-01-01

    We present in this study the significance and impacts of an innovative e-HO as a holistic and horizontal platform complementary to e-Learning to help realize transdisciplinary learning and foster integration of knowledge in higher education. A comprehensive investigation of a survey conducted among 647 university students for e-HO is presented…

  12. Small molecule activators of the Nrf2-HO-1 antioxidant axis modulate heme metabolism and inflammation in BV2 microglia cells.

    PubMed

    Foresti, Roberta; Bains, Sandip K; Pitchumony, Tamil Selvi; de Castro Brás, Lisandra E; Drago, Filippo; Dubois-Randé, Jean-Luc; Bucolo, Claudio; Motterlini, Roberto

    2013-10-01

    The nuclear factor erythroid derived 2-related factor 2 (Nrf2) and the antioxidant protein heme oxygenase-1 (HO-1) are crucial components of the cellular stress response. These two systems work together to combat oxidative stress and inflammation and are attractive drug targets for counteracting different pathologies, including neuroinflammation. We aimed to identify the most effective Nrf2/HO-1 activators that modulate the inflammatory response in microglia cells. In the present study, we searched the literature and selected 56 compounds reported to activate Nrf2 or HO-1 and analyzed them for HO-1 induction at 6 and 24h and cytotoxicity in BV2 microglial cells in vitro. Approximately 20 compounds up-regulated HO-1 at the concentrations tested (5-20 μM) with carnosol, supercurcumin, cobalt protoporphyrin-IX and dimethyl fumarate exhibiting the best induction/low cytotoxicity profile. Up-regulation of HO-1 by some compounds resulted in increased cellular bilirubin levels but did not augment the expression of proteins involved in heme synthesis (ALAS 1) or biliverdin reductase. Bilirubin production by HO-1 inducers correlated with their potency in inhibiting nitrite production after challenge with interferon-γ (INF-γ) or lipopolysaccharide (LPS). The compounds down-regulated the inflammatory response (TNF-α, PGE2 and nitrite) more strongly in cells challenged with INF-γ than LPS, and silencing HO-1 or Nrf2 with shRNA differentially affected the levels of inflammatory markers. These findings indicate that some small activators of Nrf2/HO-1 are effective modulators of microglia inflammation and highlight the chemical scaffolds that can serve for the synthesis of potent new derivatives to counteract neuroinflammation and neurodegeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Flutter Research on Skin Panels

    NASA Technical Reports Server (NTRS)

    Kordes, Eldon E.; Tuovila, Weimer J.; Guy, Lawrence D.

    1960-01-01

    Representative experimental results are presented to show the current status of the panel flutter problem. Results are presented for unstiffened rectangular panels and for rectangular panels stiffened by corrugated backing. Flutter boundaries are established for all types of panels when considered on the basis of equivalent isotropic plates. The effects of Mach number, differential pressure, and aerodynamic heating on panel flutter are discussed. A flutter analysis of orthotropic panels is presented in the appendix.

  14. An inter-comparison of HO2 measured by Fluorescence Assay by Gas Expansion and Cavity Ringdown Spectroscopy in the Highly Instrumented Reactor for Atmospheric Chemistry.

    NASA Astrophysics Data System (ADS)

    Brennan, A.; Onel, L. C.; Gianella, M.; Ronnie, G.; Aguila, A. L.; Hancock, G.; Whalley, L.; Seakins, P. W.; Ritchie, G.; Heard, D. E.

    2017-12-01

    HO2 is an important species in the atmosphere, as it is involved in the HOx radical reaction cycle that is critical to the oxidation of atmospheric pollutants and the ultimate cleaning of the troposphere. One of the most widely utilised methods to measure HO2 is Fluorescence Assay by Gas Expansion (FAGE), which indirectly measures HO2 by sampling into a low pressure cell and titrating HO2 with NO to produce OH that is then detected by Laser Induced Fluorescence. This is an indirect and non-absolute detection technique that requires careful calibration to convert the measured signal into [HO2], which involves the photolysis of H2O at 185 nm to produce OH and HO2, and is subject to 30 % errors at 2σ level. The work presented here shows the validation of the FAGE technique and its calibration procedure through inter-comparison experiments between the non-absolute FAGE technique and Cavity Ringdown Spectroscopy (CRDS), an absolute absorption based method. The CRDS system was used to excite the first O-H overtone of the HO2 absorption band at 1506.43 nm, and features a cavity length of 1.2 m and a total path of 60 km. The experiments were performed inside the 2.25 m3 stainless steel Highly Instrumented Reactor for Atmospheric Chemistry (HIRAC), using a synthetic air mixture at 150 and 1000 mbar of pressure and 298 K. HO2 was generated by photolysis of Cl2 at 365 nm in the presence of CH3OH and O2, and the [HO2] was monitored using both instruments. Additionally, monitoring the temporal decay of HO2 during its self-reaction provided an alternative calibration method for the FAGE instrument, and allowed the absorption cross section of HO2 at 1506.43 nm, σHO2, to be measured. FAGE calibration factors determined through the second order decays of HO2 at 1000 mbar agreed within 8 % of the H2O photolysis method, and determinations of σHO2 at 150 and 1000 mbar agree with previously reported data within 20 % and 12 % respectively. [HO2] correlation plots between the two

  15. Enhancement of red upconversion emission of cubic phase NaLuF{sub 4}: Yb{sup 3+}/Ho{sup 3+}/Ce{sup 3+} nanocrystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Wei, E-mail: gaowei@xupt.edu.com; Dong, Jun, E-mail: dongjun@xupt.edu.cn; Liu, Jihong

    Highlights: • The upconversion emission of Ho{sup 3+} ions was tuned from green to red. • The upconversion mechanism of Ho{sup 3+} ions was discussed based on emission spectrum. • The conversion efficiency between Ho{sup 3+} and Ce{sup 3+} were studied and calculated. - Abstract: The red upconversion emission of lanthanide-doped fluoride nanocrystals have great potential applications in color display and anticounterfeiting applications, especially for biological imaging and biomedical. In this work, a significant enhancement of red upconversion emission of Ho{sup 3+} ions was successfully obtained in the cubic phase NaLuF{sub 4} nanocrystals through codoping Ce{sup 3+} ions under NIRmore » 980 nm excitation. The ratio of red-to-green emission of Ho{sup 3+} ions was enhanced about 10-fold, which is due to two efficient cross relaxation processes derived from Ho{sup 3+} and Ce{sup 3+} ions promoted the red emission and quenched the green emission. The upconversion emission and luminescent colors of NaLuF{sub 4}: Yb{sup 3+}/Ho{sup 3+} nanocrystals were carefully investigated by a confocal microscopy setup. The possible upconversion emission mechanism and conversion efficiency of cross relaxation between Ho{sup 3+} and Ce{sup 3+} ions were discussed in detail. The current study suggests that strong red emission of NaLuF{sub 4}: Yb{sup 3+}/Ho{sup 3+}/Ce{sup 3+} nanomaterials can be used for color display and anticounterfeiting techniques.« less

  16. Registration of ‘Ho 02-113’ Sugarcane

    USDA-ARS?s Scientific Manuscript database

    Ho 02-113’ sugarcane was released by the USDA-ARS Sugarcane Research Unit working cooperatively with the Louisiana State University Agricultural Center, and the American Sugarcane League of the U.S.A. This high-fiber sugarcane variety was released for use as a biofuel feedstock to fill the rising i...

  17. Large thermal protection system panel

    NASA Technical Reports Server (NTRS)

    Weinberg, David J. (Inventor); Myers, Franklin K. (Inventor); Tran, Tu T. (Inventor)

    2003-01-01

    A protective panel for a reusable launch vehicle provides enhanced moisture protection, simplified maintenance, and increased temperature resistance. The protective panel includes an outer ceramic matrix composite (CMC) panel, and an insulative bag assembly coupled to the outer CMC panel for isolating the launch vehicle from elevated temperatures and moisture. A standoff attachment system attaches the outer CMC panel and the bag assembly to the primary structure of the launch vehicle. The insulative bag assembly includes a foil bag having a first opening shrink fitted to the outer CMC panel such that the first opening and the outer CMC panel form a water tight seal at temperatures below a desired temperature threshold. Fibrous insulation is contained within the foil bag for protecting the launch vehicle from elevated temperatures. The insulative bag assembly further includes a back panel coupled to a second opening of the foil bag such that the fibrous insulation is encapsulated by the back panel, the foil bag, and the outer CMC panel. The use of a CMC material for the outer panel in conjunction with the insulative bag assembly eliminates the need for waterproofing processes, and ultimately allows for more efficient reentry profiles.

  18. Stress associated proteins metallothionein, HO-1 and HSP 70 in human zero-hour biopsies of transplanted kidneys.

    PubMed

    August, Christian; Brockmann, Jens; Vowinkel, Thorsten; Wolters, Heiner; Dietl, Karl-Heinz; Levkau, Bodo; Heidenreich, Stefan; Lang, Detlef; Baba, Hideo A

    2006-08-01

    Light microscopic alterations reflecting both previous and preservation-induced changes in the donor organ are usually not very distinctive. The ischemia/reperfusion-associated injury depends primarily on the conditions of donor organ preservation. The present study examined human kidney biopsies with special attention paid to the molecular mechanisms of preservation-induced injury preceding reperfusion. Stress-associated proteins hemeoxygenase-1 (HO-1), heat shock protein 70 (HSP 70), and metallothionein (MT) were studied in human zero-hour biopsies of transplanted kidneys prior to reperfusion in 29 patients. Protein expression was evaluated by semiquantitative immunohistochemistry and Western blotting for HO-1 and HSP 70. These findings were correlated with terminal deoxynucleotidyltransferase-mediated 2'-deoxyuridine 5'-triphosphate-digoxigenin nick end labeling (TUNEL) staining and follow up. Compared to controls, MT and HSP 70 expression was significantly higher at zero hour. In contrast, HO-1 and the number of TUNEL-positive cells were not elevated. MT and HO-1 immunoexpression were inversely associated with graft function, and hence, were of prognostic relevance. MT and HSP 70 were sensitive to the duration of cold ischemia. MT and HO-1 are suitable indicators for tissue injury during ischemia and may serve as new predictive markers that need to be validated in further independent studies.

  19. Magnetic and magnetocaloric properties of HoCr0.75Fe0.25O3 compound

    NASA Astrophysics Data System (ADS)

    Kotnana, Ganesh; Babu, P. D.; Jammalamadaka, S. Narayana

    2018-05-01

    We report on the magnetic and magnetocaloric properties of HoCr0.75Fe0.25O3 compound around the Néel temperature (TN), which is due to Cr3+ ordering. Susceptibility (χ) vs. temperature (T) graph of HoCr0.75Fe0.25O3 compound infer two transitions due to the ordering of Cr3+ moments (TN ˜ 155 K) and Ho3+ moments (TNHo ˜ 8 K). Magnetic entropy (-ΔSM) value of 1.14 J kg-1 K-1 around 157.5 K with a magnetic field (H) of 90 kOe is attributed to antiferromagnetic (AFM) ordering of Cr3+ moments. A maximum value of adiabatic temperature (ΔTad) ˜ 0.41 K around TN is obtained and is found to increases with applied magnetic field. Negative slope for H/M vs. M2 graph is evident for HoCr0.75Fe0.25O3 compound below TN, which indicates the first order phase transition. Quantified values of -ΔSM and ΔTad open the way to explore rare earth orthochromites for the MCE properties and refrigeration applications.

  20. Substance P Induces HO-1 Expression in RAW 264.7 Cells Promoting Switch towards M2-Like Macrophages

    PubMed Central

    Montana, Giovanna

    2016-01-01

    Substance P (SP) is a neuropeptide that mediates many physiological as well as inflammatory responses. Recently, SP has been implicated in the resolution of inflammation through induction of M2 macrophages phenotype. The shift between M1-like and M2-like, allowing the resolution of inflammatory processes, also takes place by means of hemeoxygenase-1 (HO-1). HO-1 is induced in response to oxidative stress and inflammatory stimuli and modulates the immune response through macrophages polarisation. SP induces HO-1 expression in human periodontal ligament (PDL), the latter potentially plays a role in cytoprotection. We demonstrated that SP promotes M2-like phenotype from resting as well as from M1 macrophages. Indeed, SP triggers the production of interleukine-10 (IL-10), interleukine-4 (IL-4) and arginase-1 (Arg1) without nitric oxide (NO) generation. In addition, SP increases HO-1 expression in a dose- and time-dependent manner. Here we report that SP, without affecting cell viability, significantly reduces the production of pro-inflammatory cytokines and enzymes, such as tumor necrosis factor-alpha (TNF-α), interleukine-6 (IL-6), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and ameliorates migration and phagocytic properties in LPS-stimulated RAW 264.7 cells. M2-like conversion required retention of NF-κB p65 into the cytoplasm and HO-1 induced expression. Silencing of the HO-1 mRNA expression reversed the induction of pro-inflammatory cytokines in RAW 264.7 stimulated by LPS and down-regulated anti-inflammatory hallmarks of M2 phenotype. In conclusion, our data show that SP treatment might be associated with anti-inflammatory effects in LPS-stimulated RAW 264.7 cells by suppressing NF-κB activation and inducing HO-1 expression. PMID:27907187

  1. Yields of O2(b 1 Sigma g +) from reactions of HO2. [in planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Keyser, L. F.; Choo, K. Y.; Leu, M. T.

    1985-01-01

    The production of O2(b 1 Sigma g +) has been monitored for several reactions of the HO2 radical at 300 K using a discharge-flow apparatus with resonance fluorescence and chemiluminescence detection. In all cases, the resulting quantum efficiencies were found to be less than 0.03. O2(b) was observed when F atoms were added to H2O2 in the gas phase. The signal strengths of O2(b) were proportional to initial concentrations of HO2 formed by the F + H2O2 reaction. Observed /O2(b)/, /HO2/, and /OH/ vs /F/0 were analyzed using a simple three-step mechanism and a more complete computer simulation with 22 reaction steps. The results indicate that the F + HO2 reaction yields O2(b) with an efficiency of (3.6 + or - 1.4) x 10 to the -3rd. Yields from the O + OH2 reaction were less than 0.02, indicating that this reaction cannot be a major source of the O2(b) emission observed in the earth's nightglow.

  2. The “Virtual” Panel: A Computerized Model for LGBT Speaker Panels

    PubMed Central

    Beasley, Christopher; Torres-Harding, Susan; Pedersen, Paula J.

    2012-01-01

    Recent societal trends indicate more tolerance for homosexuality, but prejudice remains on college campuses. Speaker panels are commonly used in classrooms as a way to educate students about sexual diversity and decrease negative attitudes toward sexual diversity. The advent of computer delivered instruction presents a unique opportunity to broaden the impact of traditional speaker panels. The current investigation examined the influence of an interactive “virtual” gay and lesbian speaker panel on cognitive, affective, and behavioral homonegativity. Findings suggest the computer-administered panel is lowers homonegativity, particularly for affective experiential homonegativity. The implications of these findings for research and practice are discussed. PMID:23646036

  3. Hepatic (Liver) Function Panel

    MedlinePlus

    ... Educators Search English Español Blood Test: Hepatic (Liver) Function Panel KidsHealth / For Parents / Blood Test: Hepatic (Liver) ... kidneys ) is working. What Is a Hepatic (Liver) Function Panel? A liver function panel is a blood ...

  4. Passive Q-switching of microchip lasers based on Ho:YAG ceramics.

    PubMed

    Lan, R; Loiko, P; Mateos, X; Wang, Y; Li, J; Pan, Y; Choi, S Y; Kim, M H; Rotermund, F; Yasukevich, A; Yumashev, K; Griebner, U; Petrov, V

    2016-06-20

    A Ho:YAG ceramic microchip laser pumped by a Tm fiber laser at 1910 nm is passively Q-switched by single- and multi-layer graphene, single-walled carbon nanotubes (SWCNTs), and Cr2+:ZnSe saturable absorbers (SAs). Employing SWCNTs, this laser generated an average power of 810 mW at 2090 nm with a slope efficiency of 68% and continuous wave to Q-switching conversion efficiency of 70%. The shortest pulse duration was 85 ns at a repetition rate of 165 kHz, and the pulse energy reached 4.9 μJ. The laser performance and pulse stability were superior compared to graphene SAs even for a different number of graphene layers (n=1 to 4). A model for the description of the Ho:YAG laser Q-switched by carbon nanostructures is presented. This modeling allowed us to estimate the saturation intensity for multi-layered graphene and SWCNT SAs to be 1.2±0.2 and 7±1  MW/cm2, respectively. When using Cr2+:ZnSe, the Ho:YAG microchip laser generated 11 ns/25 μJ pulses at a repetition rate of 14.8 kHz.

  5. Diode-Pumped Long-Pulse-Length Ho:Tm:YLiF4 Laser at 10 Hz

    NASA Technical Reports Server (NTRS)

    Jani, Mahendra G.; Naranjo, Felipe L.; Barnes, Norman P.; Murray, Keith E.; Lockard, George E.

    1995-01-01

    An optical efficiency of 0.052 under normal mode operation for diode-pumped Ho:Tm:YLiF4 at a pulse repetition frequency of 10 Hz has been achieved. Laser output energy of 30 mJ in single Q-switched pulses with 600-ns pulse length were obtained for an input energy of 3 J. A diffusion-bonded birefringent laser rod consisting of Ho:Tm-doped and undoped pieces of YLF was utilized for 10-Hz operation.

  6. Monte Carlo simulation of liver cancer treatment with 166Ho-loaded glass microspheres

    NASA Astrophysics Data System (ADS)

    da Costa Guimarães, Carla; Moralles, Maurício; Roberto Martinelli, José

    2014-02-01

    Microspheres loaded with pure beta-emitter radioisotopes are used in the treatment of some types of liver cancer. The Instituto de Pesquisas Energéticas e Nucleares (IPEN) is developing 166Ho-loaded glass microspheres as an alternative to the commercially available 90Y microspheres. This work describes the implementation of a Monte Carlo code to simulate both the irradiation effects and the imaging of 166Ho and 90Y sources localized in different parts of the liver. Results obtained with the code and perspectives for the future are discussed.

  7. Efficient 2 μm emission and energy transfer mechanism of Ho3+ doped fluorophosphate glass sensitized by Er3+ ions

    NASA Astrophysics Data System (ADS)

    Gao, Xinyu; Tian, Ying; Liu, Qunhuo; Yang, Shuai; Jing, Xufeng; Zhang, Junjie; Xu, Shiqing

    2018-06-01

    Fluorophosphate glass co-doped with Er3+ and Ho3+ ions has been synthesized by high temperature melting method. Using a commercially available 980 nm laser diode, intense about 2 μm emissions were successfully obtained in present Ho3+/Er3+ co-doped glasses without obvious quenching. To understand 2 μm fluorescence behaviors of the prepared glasses, 1.55 μm emission spectra, energy transfer mechanism and microparameters from different levels of Er3+ to Ho3+ ions have been obtained and discussed. As a result, the Er3+/Ho3+ co-doped fluorophosphate glass with excellent spectroscopic properties might be appropriate host material for 2 μm solid laser.

  8. HO2NO2 and HNO3 in the coastal Antarctic winter night: A "lab-in-the-field" experiment

    NASA Astrophysics Data System (ADS)

    Jones, Anna; Brough, Neil; Anderson, Philip; Wolff, Eric

    2015-04-01

    Observations of peroxynitric acid (HO2NO2) and nitric acid (HNO3) were made during a 4 month period of Antarctic winter darkness at the coastal Antarctic research station, Halley. Mixing ratios of HNO3 ranged from instrumental detection limits to 8 parts per trillion by volume (pptv), and of HO2NO2 from detection limits to 5 pptv; the average ratio of HNO3:HO2NO2 was 2.0(±0.6):1, with HNO3 always present at greater mixing ratios than HO2NO2 during the winter darkness. An extremely strong association existed for the entire measurement period between mixing ratios of the respective trace gases and temperature: for HO2NO2, R2 = 0.72, and for HNO3, R2 = 0.70. We focus on three cases with considerable variation in temperature, where wind speeds were low and constant, such that, with the lack of photochemistry, changes in mixing ratio were likely to be driven by physical mechanisms alone. We derived enthalpies of adsorption (ΔHads) for these three cases. The average ΔHads for HNO3 was -42±2 kJ.mol-1 and for HO2NO2 was -56±1kJ.mol-1; these values are extremely close to those derived in laboratory studies. This exercise demonstrates i) that adsorption to/desorption from the snow pack should be taken into account when addressing budgets of boundary layer HO2NO2 and HNO3 at any snow-covered site, and ii) that Antarctic winter can be used as a natural 'laboratory in the field' for testing data on physical exchange mechanisms.

  9. Antinuclear antibody panel

    MedlinePlus

    ... ANA panel; ANA reflexive panel; SLE - ANA; Systemic lupus erythematosus - ANA ... have signs of an autoimmune disorder, particularly systemic lupus erythematosus . This test may be done if you ...

  10. Mechanism of estrogen-mediated attenuation of hepatic injury following trauma-hemorrhage: Akt-dependent HO-1 up-regulation.

    PubMed

    Hsu, Jun-Te; Kan, Wen-Hong; Hsieh, Chi-Hsun; Choudhry, Mashkoor A; Schwacha, Martin G; Bland, Kirby I; Chaudry, Irshad H

    2007-10-01

    Protein kinase B (Akt) is known to be involved in proinflammatory and chemotactic events in response to injury. Akt activation also leads to the induction of heme oxygenase (HO)-1. Up-regulation of HO-1 mediates potent, anti-inflammatory effects and attenuates organ injury. Although studies have shown that 17beta-estradiol (E2) prevents organ damage following trauma-hemorrhage, it remains unknown whether Akt/HO-1 plays any role in E2-mediated attenuation of hepatic injury following trauma-hemorrhage. To study this, male rats underwent trauma-hemorrhage (mean blood pressure, approximately 40 mmHg for 90 min), followed by fluid resuscitation. At the onset of resuscitation, rats were treated with vehicle, E2 (1 mg/kg body weight), E2 plus the PI-3K inhibitor (Wortmannin), or the estrogen receptor (ER) antagonist (ICI 182,780). At 2 h after sham operation or trauma-hemorrhage, plasma alpha-GST and hepatic tissue myeloperoxidase (MPO) activity, IL-6, TNF-alpha, ICAM-1, cytokine-induced neutrophil chemoattractant-1, and MIP-2 levels were measured. Hepatic Akt and HO-1 protein levels were also determined. Trauma-hemorrhage increased hepatic injury markers (alpha-GST and MPO activity), cytokines, ICAM-1, and chemokine levels. These parameters were markedly improved in the E2-treated rats following trauma-hemorrhage. E2 treatment also increased hepatic Akt activation and HO-1 expression compared with vehicle-treated, trauma-hemorrhage rats, which were abolished by coadministration of Wortmannin or ICI 182,780. These results suggest that the salutary effects of E2 on hepatic injury following trauma-hemorrhage are in part mediated via an ER-related, Akt-dependent up-regulation of HO-1.

  11. A Ho(III) potentiometric polymeric membrane sensor based on a new four dentate neutral ion carrier.

    PubMed

    Zamani, Hassan Ali; Zanganeh-Asadabadi, Abbas; Rohani, Mitra; Zabihi, Mohammad Saleh; Fadaee, Javad; Ganjali, Mohammad Reza; Faridbod, Farnoush; Meghdadi, Soraia

    2013-03-01

    In this research, we report a new Ho(3+)-PVC membrane electrode based on N-(4,5-dimethyl-2-(picolinamido)phenyl)picolinamide (H(2)Me(2)bpb) as a suitable ion carrier. Poly vinylchloride (PVC)-based membrane composed of H(2)Me(2)bpb with oleic acid (OA) as anionic additives, and o-nitrophenyloctyl ether (NPOE) as plasticized solvent mediator. The sensor exhibits a Nernstian slope of 20.1 ± 0.2 mV decade(-1) over the concentration range of 1.0 × 10(-6) to 1.0 × 1(-2) mol L(-1), and a detection limit of 5.0 × 10(-7) mol L(-1) of Ho(3+) ions. The potentiometric response of the sensor is independent of the solution pH in the range of 3.5-9.4. It has a very short response time, in the whole concentration range (<10s), and can be used for at least eight weeks. The proposed electrode shows a good selectivity towards Ho(3+) ions over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. To assess its analytical applicability the proposed Ho(3+) sensor was successfully applied as an indicator electrode in the titration of Ho(3+) ion solutions in certified reference materials, alloy samples and for the determination of the fluoride ion in two mouthwash preparations. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. HO-1 and CO decrease platelet-derived growth factor-induced vascular smooth muscle cell migration via inhibition of Nox1

    PubMed Central

    Rodriguez, Andres I.; Gangopadhyay, Archana; Kelley, Eric E.; Pagano, Patrick J.; Zuckerbraun, Brian S.; Bauer, Philip M.

    2009-01-01

    Objective Heme oxygenase-1 (HO-1), via its enzymatic degradation products, exhibits cell and tissue protective effects in models of vascular injury and disease. The migration of vascular smooth muscle cells (VSMC) from the medial to the intimal layer of blood vessels plays an integral role in the development of a neointima in these models. Despite this, there are no studies addressing the effect of increased HO-1 expression on VSMC migration. Results and Methods The effects of increased HO-1 expression as well as biliverdin, bilirubin, and carbon monoxide (CO), were studied in in vitro models of VSMC migration. Induction of HO-1 or CO, but not biliverdin or bilirubin, inhibited VSMC migration. This effect was mediated by the inhibition of Nox1 as determined by a range of approaches including detection of intracellular superoxide, NADPH oxidase activity measurements, and siRNA experiments. Furthermore, CO decreased PDGF-stimulated, redox-sensitive signaling pathways. Conclusion Herein we demonstrate that increased HO-1 expression and CO decreases PDGF-stimulated VSMC migration via inhibition of Nox1 enzymatic activity. These studies reveal a novel mechanism by which HO-1 and CO may mediate their beneficial effects in arterial inflammation and injury. PMID:19875720

  13. Heterogeneous photochemistry of imidazole-2-carboxaldehyde: HO2 radical formation and aerosol growth

    NASA Astrophysics Data System (ADS)

    González Palacios, Laura; Corral Arroyo, Pablo; Aregahegn, Kifle Z.; Steimer, Sarah S.; Bartels-Rausch, Thorsten; Nozière, Barbara; George, Christian; Ammann, Markus; Volkamer, Rainer

    2016-09-01

    The multiphase chemistry of glyoxal is a source of secondary organic aerosol (SOA), including its light-absorbing product imidazole-2-carboxaldehyde (IC). IC is a photosensitizer that can contribute to additional aerosol ageing and growth when its excited triplet state oxidizes hydrocarbons (reactive uptake) via H-transfer chemistry. We have conducted a series of photochemical coated-wall flow tube (CWFT) experiments using films of IC and citric acid (CA), an organic proxy and H donor in the condensed phase. The formation rate of gas-phase HO2 radicals (PHO2) was measured indirectly by converting gas-phase NO into NO2. We report on experiments that relied on measurements of NO2 formation, NO loss and HONO formation. PHO2 was found to be a linear function of (1) the [IC] × [CA] concentration product and (2) the photon actinic flux. Additionally, (3) a more complex function of relative humidity (25 % < RH < 63 %) and of (4) the O2 / N2 ratio (15 % < O2 / N2 < 56 %) was observed, most likely indicating competing effects of dilution, HO2 mobility and losses in the film. The maximum PHO2 was observed at 25-55 % RH and at ambient O2 / N2. The HO2 radicals form in the condensed phase when excited IC triplet states are reduced by H transfer from a donor, CA in our system, and subsequently react with O2 to regenerate IC, leading to a catalytic cycle. OH does not appear to be formed as a primary product but is produced from the reaction of NO with HO2 in the gas phase. Further, seed aerosols containing IC and ammonium sulfate were exposed to gas-phase limonene and NOx in aerosol flow tube experiments, confirming significant PHO2 from aerosol surfaces. Our results indicate a potentially relevant contribution of triplet state photochemistry for gas-phase HO2 production, aerosol growth and ageing in the atmosphere.

  14. Mechanisms of HO-1 mediated attenuation of renal immune injury: a gene profiling study.

    PubMed

    Duann, Pu; Lianos, Elias A

    2011-10-01

    Using a mouse model of immune injury directed against the renal glomerular vasculature and resembling human forms of glomerulonephritis (GN), we assessed the effect of targeted expression of the cytoprotective enzyme heme oxygenase (HO)-1. A human (h) HO-1 complementary DNAN (cDNA) sequence was targeted to glomerular epithelial cells (GECs) using a GEC-specific murine nephrin promoter. Injury by administration of antibody against the glomerular basement membrane (anti-GBM) to transgenic (TG) mice with GEC-targeted hHO-1 was attenuated compared with wild-type (WT) controls. To explore changes in the expression of genes that could mediate this salutary effect, we performed gene expression profiling using a microarray analysis of RNA isolated from the renal cortex of WT or TG mice with or without anti-GBM antibody-induced injury. Significant increases in expression were detected in 9 major histocompatibility complex (MHC)-class II genes, 2 interferon-γ (IFN-γ)-inducible guanosine triphosphate (GTP)ases, and 3 genes of the ubiquitin-proteasome system. The increase in MHC-class II and proteasome gene expression in TG mice with injury was validated by real-time polymerase chain reaction (PCR) or Western blot analysis. The observations point to novel mechanisms underlying the cytoprotective effect of HO-1 in renal immune injury. Copyright © 2011. Published by Mosby, Inc.

  15. Registration of ‘HoCP 04-838’ sugarcane

    USDA-ARS?s Scientific Manuscript database

    HoCP 04-838’ sugarcane (an interspecific hybrid of S. officinarum, S. barberi Jeswiet, S. spontaneum, and S. sinense Roxb. amend. Jeswiet) was selected and evaluated by scientists at the USDA-ARS, working cooperatively with the Louisiana State University Agricultural Center, and the American Sugar ...

  16. Homozygous familial hypercholesterolemia (HoFH) in Germany: an epidemiological survey.

    PubMed

    Walzer, S; Travers, K; Rieder, S; Erazo-Fischer, E; Matusiewicz, D

    2013-01-01

    In Europe a disease is recognized as rare if less than 1 in 2000 people suffer from the specific disease. In patients with familial homozygous hypercholesterolemia (HoFH) the accumulation of low-density lipoprotein cholesterol (LDL-C) leads to generalized atherosclerosis due to an insufficient functioning of the LDL-C receptors. Patients die early sometimes even in the mid-30s, from myocardial infarction or stroke. For the German population, insufficient epidemiological evidence exists. A systematic literature search in EMBASE and Medline was performed in conjunction with a targeted manual search for epidemiological HoFH studies. Additionally a nationwide survey was conducted in Germany in all identified apheresis- and lipid centers. The purpose of the survey was the validation of the systematic literature search results based on empirical (practice) data. In total 961 publications were found, 874 were excluded based on pre-defined exclusion criteria leaving only 87 for further review. After review of the identified abstracts (n = 87) 23 publications were identified as epidemiological studies. Only one publication was found which reported a prevalence of 1:1,000,000. The qualitative survey among 187 physicians in Germany also revealed a low prevalence: 95 HoFH patients were identified in 35 centers. The estimated frequency of homozygous familial hypercholesterolemia patients in Germany is around 95 (1:860,000) and the disease should be recognized as rare according to the definition of the European Medical Agency.

  17. TRMM Solar Array Panels

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This final report presents conclusions/recommendations concerning the TRMM Solar Array; deliverable list and schedule summary; waivers and deviations; as-shipped performance data, including flight panel verification matrix, panel output detail, shadow test summary, humidity test summary, reverse bias test panel; and finally, quality assurance summary.

  18. Single crystal growth and anisotropic magnetic properties of HoAl2Ge2

    NASA Astrophysics Data System (ADS)

    Matin, Md.; Mondal, Rajib; Thamizhavel, A.; Provino, A.; Manfrinetti, P.; Dhar, S. K.

    2018-05-01

    We have grown a single crystal of HoAl2Ge2, which crystallizes in the hexagonal CaAl2Si2 type structure with Ho ions in the trigonal coordination in the ab plane. The data obtained from the bulk measurement techniques of magnetization, heat capacity and transport reveal that HoAl2Ge2 orders antiferromagnetically at TN ˜6.5 K. The susceptibility below TN and isothermal magnetization at 2 K indicate the ab plane as the easy plane of magnetization. Heat capacity data reveal a prominent Schottky anomaly with a broad peak centered around 25 K, suggesting a relatively low crystal electric field (CEF) splitting. The electrical resistivity reveals the occurrence of a superzone gap below TN. The point charge model of the CEF is applied to the magnetization and the heat capacity data. While a good fit to the paramagnetic susceptibility is obtained, the CEF parameters do not provide a satisfactory fit to the isothermal magnetization at 2 K and the Schottky anomaly.

  19. 2  μm laser oscillation of Ho3+:Tm3+-codoped silica microspheres.

    PubMed

    Peng, Longxiang; Huang, Yantang; Duan, Yafan; Zhuang, Shijian; Liao, Tingdi; Xu, Canhua

    2017-09-10

    2 μm laser oscillation with a low threshold has been achieved in Ho 3+ :Tm 3+ -codoped silica microspheres (HTCSMs). Ho 3+ :Tm 3+ -codoped solgel functionalization film is applied to the surface of a silica microsphere, and an optical tapered fiber is adopted to couple an 808 nm continuous-wave laser to serve as the pump light source. Multimode and single-mode laser oscillations around 2 μm within the eye-safe wave band are observed due to the I 7 5→I 8 5 transitions of Ho 3+ ions sensitized by Tm 3+ . The morphology characteristics of microspheres determine the multimode laser oscillation spectrum. The free spectral range is in good accordance with the calculated value based on Mie scattering theory. The HTCSM laser oscillation shows characteristics of good capability, simple process, high flexibility, and low cost.

  20. High beam quality of a Q-switched 2-µm Tm,Ho:LuVO4 laser

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Yang, Xining; Shen, Yingjie; Li, Linjun; Zhou, Long; Yang, Yuqiang; Bai, Yunfeng; Xie, Wenqiang; Ye, Guangchao; Yu, Xiaoyang

    2018-05-01

    A diode-end-pumped 2.05-µm Q-switched Tm,Ho:LuVO4 laser is reported in this paper. The cryogenic Tm3+ (5.0 at.%),Ho3+ (0.5 at.%):LuVO4 crystal was pumped by an 800-nm laser diode. At a pulse repetition frequency of 10 kHz, the maximum average output power of 3.77 W was achieved at 77 K when an incident pump power of 14.7 W was used. The slope efficiency and optical-optical conversion efficiency were 28.3 and 25.6%, respectively. The maximum per pulse energy was 2.54 mJ for a pulse duration of 69.9 ns. The beam quality factor Mx 2 was approximately 1.17 and My 2 was approximately 1.01 for the Tm,Ho:LuVO4 laser.

  1. Pulsed laser photolysis study of the reaction between O(3P) and HO2

    NASA Technical Reports Server (NTRS)

    Ravishankara, A. R.; Wine, P. H.; Nicovich, J. M.

    1983-01-01

    It is pointed out that bimolecular reactions involving two free radicals are of great interest because both reactants have unpaired electrons and hence could interact at distances longer than those typical of radical-molecule encounters. A method based on laser photolysis is being developed to produce selectively free radicals in the homogeneous gas phase. This is to be done in such a way as to isolate the reaction of interest and subsequently follow the course of the reaction using spectroscopic techniques. The present investigation is concerned with a study in which the rate coefficient for the reaction of O(3P) with HO2, has been measured at N2 pressures ranging from 10 to 500 torr, taking into account the reaction O(3P)+HO2 yields OH-O2. In the described study, O(3P) and HO2 were produced by cophotolysis of O3 and H2O2 in N2 at 248.5 nm using a KrF excimer laser.

  2. Momentum and charge transport in non-relativistic holographic fluids from Hořava gravity

    NASA Astrophysics Data System (ADS)

    Davison, Richard A.; Grozdanov, Sašo; Janiszewski, Stefan; Kaminski, Matthias

    2016-11-01

    We study the linearized transport of transverse momentum and charge in a conjectured field theory dual to a black brane solution of Hořava gravity with Lifshitz exponent z = 1. As expected from general hydrodynamic reasoning, we find that both of these quantities are diffusive over distance and time scales larger than the inverse temperature. We compute the diffusion constants and conductivities of transverse momentum and charge, as well the ratio of shear viscosity to entropy density, and find that they differ from their relativistic counterparts. To derive these results, we propose how the holographic dictionary should be modified to deal with the multiple horizons and differing propagation speeds of bulk excitations in Hořava gravity. When possible, as a check on our methods and results, we use the covariant Einstein-Aether formulation of Hořava gravity, along with field redefinitions, to re-derive our results from a relativistic bulk theory.

  3. Expression and characterization of truncated human heme oxygenase (hHO-1) and a fusion protein of hHO-1 with human cytochrome P450 reductase.

    PubMed

    Wilks, A; Black, S M; Miller, W L; Ortiz de Montellano, P R

    1995-04-04

    A human heme oxygenase (hHO-1) gene without the sequence coding for the last 23 amino acids has been expressed in Escherichia coli behind the pho A promoter. The truncated enzyme is obtained in high yields as a soluble, catalytically-active protein, making it available for the first time for detailed mechanistic studies. The purified, truncated hHO-1/heme complex is spectroscopically indistinguishable from that of the rat enzyme and converts heme to biliverdin when reconstituted with rat liver cytochrome P450 reductase. A self-sufficient heme oxygenase system has been obtained by fusing the truncated hHO-1 gene to the gene for human cytochrome P450 reductase without the sequence coding for the 20 amino acid membrane binding domain. Expression of the fusion protein in pCWori+ yields a protein that only requires NADPH for catalytic turnover. The failure of exogenous cytochrome P450 reductase to stimulate turnover and the insensitivity of the catalytic rate toward changes in ionic strength establish that electrons are transferred intramolecularly between the reductase and heme oxygenase domains of the fusion protein. The Vmax for the fusion protein is 2.5 times higher than that for the reconstituted system. Therefore, either the covalent tether does not interfere with normal docking and electron transfer between the flavin and heme domains or alternative but equally efficient electron transfer pathways are available that do not require specific docking.

  4. Predicting outcome in acute severe ulcerative colitis: comparison of the Travis and Ho scores using UK IBD audit data.

    PubMed

    Lynch, R W; Churchhouse, A M D; Protheroe, A; Arnott, I D R

    2016-06-01

    Acute severe ulcerative colitis is categorised using the Truelove & Witts criteria. The Travis and the Ho scores are calculated following 72 h of steroid treatment to identify patients at risk of failing steroid therapy who require colectomy or second-line medical therapy. To compare the Travis and the Ho scores in a large unselected cohort to determine which might be more clinically relevant. We analysed 3049 patients with ulcerative colitis from the 2010 round of the UK IBD audit of which 984 had acute severe ulcerative colitis. 420 patients had sufficient data for analysis. Patients were allocated into either a Travis high- or low-risk group and either a Ho high-, intermediate- or low-risk group. We assessed whether further medical or surgical intervention and outcomes varied between groups. High-risk patients in Travis and the Ho groups, when compared to lower risk groups, were more likely to fail steroid therapy: 64.5% (131/203) vs. 38.7% (84/217) (P < 0.0001) for Travis and 66.2% (96/145) vs. 46.7% (85/182) vs. 36.6% (34/93) (P < 0.0001) for Ho. They were also more likely to undergo surgery 34.0% (69/203) vs. 9.7% (21/217) for Travis and 33.1% (48/145) vs. 17.0% (31/182) vs. 11.8% (11/93) (P < 0.0001) for Ho. Travis high patients were more likely to be refractory to second-line medical therapy: 44.6% (37/83) vs. 20.0% (9/45) (P = 0.01). Patients identified as high risk using the Travis or the Ho scoring systems are more likely to be resistant to IV steroids and require surgery. Risk of surgery in both high-risk populations is lower than previously reported. © 2016 John Wiley & Sons Ltd.

  5. Broad band and enhanced photocatalytic behaviour of Ho3+-doped Bi2O3 micro-rods

    NASA Astrophysics Data System (ADS)

    Prasad, Neena; Karthikeyan, Balasubramanian

    2018-06-01

    Band-gap-tuned Bi2O3 micro-rods were synthesized using simple co-precipitation method by doping 5 wt% Ho3+ to mitigate the concentration of toxic dye from the polluted water using it as a photocatalyst. Structure and morphology of the prepared samples were identified using powder X-ray diffraction technique and scanning electron microscopy (SEM). Elemental composition and chemical state of the prepared samples were analyzed from the X-ray photoelectron spectroscopy (XPS). Considerable absorption in IR region was observed for Ho3+ doped Bi2O3 due to the electronic transitions of 5I8→5F4, 5I8→5F5, and 5I8→5I5, 5I6. The excellent ultra-violet (UV), white and infrared light (IR)-driven photocatalytic activity were suggested for pure and doped Bi2O3 samples. Ho3+-doped Bi2O3 micro-rods exhibits a better photocatalytic activity under white light irradiation. The consequence of the bandgap and the synergetic effect of Ho3+ and Bi2O3 on the photocatalytic degradation of MB were investigated.

  6. Optimization of aircraft interior panels

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Roper, Willard D.

    1986-01-01

    Eight different graphite composite panels were fabricated using four different resin matrices. The resin matrices included Hercules 71775, a blend of vinylpolystyrpyridine and bismaleimide, H795, a bismaleimide, Cycom 6162, a phenolic, and PSP 6022M, a polystyrylpyridine. Graphite panels were fabricated using fabric or unidirectional tape. This report describes the processes for preparing these panels and some of their mechanical, thermal and flammability properties. Panel properties are compared with state-of-the-art epoxy fiberglass composite panels.

  7. Composite panel development at JPL

    NASA Technical Reports Server (NTRS)

    Mcelroy, Paul; Helms, Rich

    1988-01-01

    Parametric computer studies can be use in a cost effective manner to determine optimized composite mirror panel designs. An InterDisciplinary computer Model (IDM) was created to aid in the development of high precision reflector panels for LDR. The materials properties, thermal responses, structural geometries, and radio/optical precision are synergistically analyzed for specific panel designs. Promising panels designs are fabricated and tested so that comparison with panel test results can be used to verify performance prediction models and accommodate design refinement. The iterative approach of computer design and model refinement with performance testing and materials optimization has shown good results for LDR panels.

  8. Calculation of the rate constant for state-selected recombination of H+O2(v) as a function of temperature and pressure

    NASA Astrophysics Data System (ADS)

    Teitelbaum, Heshel; Caridade, Pedro J. S. B.; Varandas, António J. C.

    2004-06-01

    Classical trajectory calculations using the MERCURY/VENUS code have been carried out on the H+O2 reactive system using the DMBE-IV potential energy surface. The vibrational quantum number and the temperature were selected over the ranges v=0 to 15, and T=300 to 10 000 K, respectively. All other variables were averaged. Rate constants were determined for the energy transfer process, H+O2(v)-->H+O2(v''), for the bimolecular exchange process, H+O2(v)-->OH(v')+O, and for the dissociative process, H+O2(v)-->H+O+O. The dissociative process appears to be a mere extension of the process of transferring large amounts of energy. State-to-state rate constants are given for the exchange reaction, and they are in reasonable agreement with previous results, while the energy transfer and dissociative rate constants have never been reported previously. The lifetime distributions of the HO2 complex, calculated as a function of v and temperature, were used as a basis for determining the relative contributions of various vibrational states of O2 to the thermal rate coefficients for recombination at various pressures. This novel approach, based on the complex's ability to survive until it collides in a secondary process with an inert gas, is used here for the first time. Complete falloff curves for the recombination of H+O2 are also calculated over a wide range of temperatures and pressures. The combination of the two separate studies results in pressure- and temperature-dependent rate constants for H+O2(v)(+Ar)⇄HO2(+Ar). It is found that, unlike the exchange reaction, vibrational and rotational-translational energy are liabilities in promoting recombination.

  9. Proposed strategies for designing sustainable high-rise apartment buildings in Ho Chi Minh City responding to critical urban issues

    NASA Astrophysics Data System (ADS)

    Truong, Nguyen Hoang Long; Huan Giang, Ngoc; Binh Duong, Trong

    2018-03-01

    This paper aims at finding practical strategies for designing sustainable high-rise apartment buildings in Ho Chi Minh City responding to varied municipal issues. Two steps are made. Step-1 identifies the critical issues of Ho Chi Minh City which are associated with high-rise apartment building projects. Step-2 finds potential and applicable strategies which are solutions for the critical issues in Step-1 with reference of seven selected assessment methods. The study finds the set of 58 strategies applicable to designing sustainable high-rise apartment buildings in Ho Chi Minh City.

  10. Energy transfer processes between Tm(3+) and Ho(3+) in LiYF4. Ph.D. Thesis Final Report

    NASA Technical Reports Server (NTRS)

    Oezen, Goenuel

    1991-01-01

    The spectroscopic properties of the crystal LiYF4 doped with Thulium (Tm) and Holmium (Ho) ions are studied. The basic processes are discussed that regulate the transfer of energy between these two ions in this crystal. In this system Tm is considered the donor ion and the Ho the acceptor ion. Spectral data were obtained on three samples available: LiYF4:Tm(3+) (0.5 percent), LiYF4:Ho(3+) (1 percent), and LiYF4:Tm(3+) (5 percent), Ho(3+) (0.2 percent). Spectral data, which include absorption, luminescence, excitation, and the response to pulsed excitation in a wide range of temperatures, allowed to look at the energy transfer processes by considering the kinetic evolution of the emission of the two ions (donor and acceptor) involved in the process and the basic spectroscopic properties related to them. This inclusive approach has led to the validation of the physical model.

  11. Direct observation of low energy nuclear spin excitations in HoCrO3 by high resolution neutron spectroscopy.

    PubMed

    Chatterji, T; Jalarvo, N; Kumar, C M N; Xiao, Y; Brückel, Th

    2013-07-17

    We have investigated low energy nuclear spin excitations in the strongly correlated electron compound HoCrO3. We observe clear inelastic peaks at E = 22.18 ± 0.04 μeV in both energy loss and gain sides. The energy of the inelastic peaks remains constant in the temperature range 1.5-40 K at which they are observed. The intensity of the inelastic peak increases at first with increasing temperature and then decreases at higher temperatures. The temperature dependence of the energy and intensity of the inelastic peaks is very unusual compared to that observed in other Nd, Co, V and also simple Ho compounds. Huge quasielastic scattering appears at higher temperatures presumably due to the fluctuating electronic moments of the Ho ions that get increasingly disordered at higher temperatures. The strong quasielastic scattering may also originate in the first Ho crystal-field excitations at about 1.5 meV.

  12. Manipulating the wavelength-drift of a Tm laser for resonance enhancement in an intra-cavity pumped Ho laser.

    PubMed

    Huang, Haizhou; Huang, Jianhong; Liu, Huagang; Li, Jinhui; Lin, Zixiong; Ge, Yan; Dai, Shutao; Deng, Jing; Lin, Wenxiong

    2018-03-05

    We demonstrate an enhancement mechanism and thermal model for intra-cavity pumped lasers, where resonance enhancement in intra-cavity pumped Ho laser was achieved by manipulating the wavelength-drift nature of the Tm laser for the first time. Optical conversion efficiency of 37.5% from an absorbed 785 nm diode laser to a Ho laser was obtained with a maximum output power of 7.51 W at 2122 nm, which is comparable to the conversion efficiency in 1.9 μm LD pumped Ho lasers. Meanwhile, more severe thermal effects in the Ho-doped gain medium than the Tm-doped one at high power operation were verified based on the built thermal model. This work benefits the design or evaluation of intra-cavity pumped lasers, and the resonance enhancement originated from the difference in reabsorption loss between stark levels at the lasing manifolds of quasi-three-level rare-earth ions has great interest to improve the existing intra-cavity pumped lasers or explore novel lasers.

  13. A Prospective Multi-Center Observational Study of Children Hospitalized with Diarrhea in Ho Chi Minh City, Vietnam

    PubMed Central

    Thompson, Corinne N.; Phan, My V. T.; Hoang, Nguyen Van Minh; Minh, Pham Van; Vinh, Nguyen Thanh; Thuy, Cao Thu; Nga, Tran Thi Thu; Rabaa, Maia A.; Duy, Pham Thanh; Dung, Tran Thi Ngoc; Phat, Voong Vinh; Nga, Tran Vu Thieu; Tu, Le Thi Phuong; Tuyen, Ha Thanh; Yoshihara, Keisuke; Jenkins, Claire; Duong, Vu Thuy; Phuc, Hoang Le; Tuyet, Pham Thi Ngoc; Ngoc, Nguyen Minh; Vinh, Ha; Chinh, Nguyen Tran; Thuong, Tang Chi; Tuan, Ha Manh; Hien, Tran Tinh; Campbell, James I.; Chau, Nguyen Van Vinh; Thwaites, Guy; Baker, Stephen

    2015-01-01

    We performed a prospective multicenter study to address the lack of data on the etiology, clinical and demographic features of hospitalized pediatric diarrhea in Ho Chi Minh City (HCMC), Vietnam. Over 2,000 (1,419 symptomatic and 609 non-diarrheal control) children were enrolled in three hospitals over a 1-year period in 2009–2010. Aiming to detect a panel of pathogens, we identified a known diarrheal pathogen in stool samples from 1,067/1,419 (75.2%) children with diarrhea and from 81/609 (13.3%) children without diarrhea. Rotavirus predominated in the symptomatic children (664/1,419; 46.8%), followed by norovirus (293/1,419; 20.6%). The bacterial pathogens Salmonella, Campylobacter, and Shigella were cumulatively isolated from 204/1,419 (14.4%) diarrheal children and exhibited extensive antimicrobial resistance, most notably to fluoroquinolones and third-generation cephalosporins. We suggest renewed efforts in generation and implementation of policies to control the sale and prescription of antimicrobials to curb bacterial resistance and advise consideration of a subsidized rotavirus vaccination policy to limit the morbidity due to diarrheal disease in Vietnam. PMID:25802437

  14. 15 mJ single-frequency Ho:YAG laser resonantly pumped by a 1.9 µm laser diode

    NASA Astrophysics Data System (ADS)

    Na, Q. X.; Gao, C. Q.; Wang, Q.; Zhang, Y. X.; Gao, M. W.; Ye, Q.; Li, Y.

    2016-09-01

    A 2.09 µm injection-seeded single-frequency Ho:YAG laser resonantly pumped by a 1.91 µm laser diode is demonstrated for the first time. The seed laser is a continuous wave (CW) Ho:YAG non-planar ring oscillator. 15.15 mJ single-frequency output energy is obtained from the injection-seeded Q-switched Ho:YAG laser, with a pulse repetition rate of 200 Hz and a pulse width of 109 ns. The half-width of the pulse spectrum is measured to be 4.19 MHz by using the heterodyne technique. The fluctuation of the center frequency of the single-frequency pulses is 1.52 MHz (root mean square (RMS)) in 1 h.

  15. Synthesis and electrical characterization of BaZr0.9Ho0.1O3-δ electrolyte ceramic for IT - SOFCs

    NASA Astrophysics Data System (ADS)

    Saini, Deepash S.; Singh, Lalit K.; Bhattacharya, D.

    2018-04-01

    A cost-effective modified combustion method using citric acid and glycine has recently been developed to synthesize high quality, and nanosized BaZr0.9Ho0.1O3 ceramic powder. BaZr0.9Ho0.1O3-δ ceramic powder was characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM). XRD pattern of BaZr0.9Ho0.1O3-δ ceramic sintered at 1600 °C has shown that pure phase of BaZr0.9Ho0.1O3-δ with cubic Pm3¯m space group symmetry. The transmission electron microscopic investigation has shown that the particle size of the powder calcined at 1100 °C was in the range 30-80 nm. The FESEM image of sintered pellet at 1600 °C for 4 h reveals porous nature of BaZr0.9Ho0.1O3-δ with 83.7 relative density. Impedance analysis reveal three type relaxations in the temperature range 250 °C to 500 °C as studied at different frequencies over 100 Hz to 1 MHz in air. The grain boundary conductivity of BaZr0.9Ho0.1O3-δ ceramic is found lower then grain (bulk) conductivity due to core-space charge layer behavior in grain boundary.

  16. The metallofullerene field-induced single-ion magnet HoSc2 N@C80.

    PubMed

    Dreiser, Jan; Westerström, Rasmus; Zhang, Yang; Popov, Alexey A; Dunsch, Lothar; Krämer, Karl; Liu, Shi-Xia; Decurtins, Silvio; Greber, Thomas

    2014-10-13

    The low-temperature magnetic properties of the endohedral metallofullerene HoSc2 N@C80 have been studied by superconducting quantum interference device (SQUID) magnetometry. Alternating current (ac) susceptibility measurements reveal that this molecule exhibits slow relaxation of magnetization in a small applied field with timescales in the order of milliseconds. The equilibrium magnetic properties of HoSc2 N@C80 indicate strong magnetic anisotropy. The large differences in magnetization relaxation times between the present compound and the previously investigated DySc2 N@C80 are discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. 6. COMPRESSOR CONTROL PANELS: AT LEFT, 6,000 P.S.I. PANEL, CIRCA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. COMPRESSOR CONTROL PANELS: AT LEFT, 6,000 P.S.I. PANEL, CIRCA 1957; AT RIGHT, FACING CAMERA, 10,000 P.S.I. PANEL. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Helium Compression Plant, Test Area 1-115, intersection of Altair & Saturn Boulevards, Boron, Kern County, CA

  18. Development of Quiet Honeycomb Panels

    NASA Technical Reports Server (NTRS)

    Palumbo, Daniel L.; Klos, Jacob

    2009-01-01

    Sandwich honeycomb composite panels are lightweight and strong, and, therefore, provide a reasonable alternative to the aluminum ring framelstringer architecture currently used for most aircraft airframes. The drawback to honeycomb panels is that they radiate noise into the aircraft cabin very efficiently provoking the need for additional sound treatment which adds weight and reduces the material's cost advantage. A series of honeycomb panels were made which incorporated different design strategies aimed at reducing the honeycomb panels' radiation efficiency while at the same time maintaining its strength. The majority of the desi gns were centered around the concept of creatin g areas of reduced stiffness in the panel by adding voids and recesses to the core. The effort culminated with a reinforced./recessed panel which had 6 dB higher transmission loss than the baseline solid core panel while maintaining comparable strength.

  19. Supersonic Panel Flutter Test Results for Flat Fiber-Glass Sandwich Panels with Foamed Cores

    NASA Technical Reports Server (NTRS)

    Tuovila, W. J.; Presnell, John G., Jr.

    1961-01-01

    Flutter tests have been made on flat panels having a 1/4 inch-thick plastic-foam core covered with thin fiber-glass laminates. The testing was done in the Langley Unitary Plan wind tunnel at Mach numbers from 1.76 t o 2.87. The flutter boundary for these panels was found to be near the flutter boundary of thin metal panels when compared on the basis of an equivalent panel stiffness. The results also demonstrated that the depth of the cavity behind the panel has a pronounced influence on flutter. Changing the cavity depth from 1 1/2 inches to 1/2 inch reduced the dynamic pressure at start of flutter by 40 percent. No flutter was obtained when the spacers on the back of the panel were against the bottom of the cavity.

  20. Panel Resource Management (PRM) Implementation and Effects within Safety Review Panel Settings and Dynamics

    NASA Technical Reports Server (NTRS)

    Taylor, Robert W.; Nash, Sally K.

    2007-01-01

    While technical training and advanced degree's assure proficiency at specific tasks within engineering disciplines, they fail to address the potential for communication breakdown and decision making errors familiar to multicultural environments where language barriers, intimidating personalities and interdisciplinary misconceptions exist. In an effort to minimize these pitfalls to effective panel review, NASA's lead safety engineers to the ISS Safety Review Panel (SRP), and Payload Safety Review Panel (PSRP) initiated training with their engineers, in conjunction with the panel chairs, and began a Panel Resource Management (PRM) program. The intent of this program focuses on the ability to reduce the barriers inhibiting effective participation from all panel attendees by bolstering participants confidence levels through increased communication skills, situational awareness, debriefing, and a better technical understanding of requirements and systems.

  1. Dosimetric intercomparison of permanent Ho-166 seed's implants and HDR Ir-192 brachytherapy in breast cancer.

    PubMed

    de Campos, Tarcisio Passos Ribeiro; Nogueira, Luciana Batista; Trindade, Bruno; Cuperschmid, Ethel Mizrahy

    2016-01-01

    To provide a comparative dosimetric analysis of permanent implants of Ho(166)-seeds and temporary HDR Ir(192)-brachytherapy through computational simulation. Brachytherapy with Ir(192)-HDR or LDR based on temporary wires or permanent radioactive seed implants can be used as dose reinforcement for breast radiation therapy. Permanent breast implants have not been a practical clinical routine; although, I(125) and Pd(103)-seeds have already been reported. Biodegradable Ho(166)-ceramic-seeds have been addressed recently. Simulations of implants of nine Ho(166)-seeds and equivalent with HDR Ir(192)-brachytherapy were elaborated in MCNP5, shaped in a computational multivoxel simulator which reproduced a female thorax phantom. Spatial dose rate distributions and dose-volume histograms were generated. Protocol's analysis involving exposure time, seed's activities and dose were performed. Permanent Ho(166)-seed implants presented a maximum dose rate per unit of contained activity (MDR) of 1.1601 μGy h(-1) Bq(-1); and, a normalized MDR in standard points (8 mm, equidistant to 03-seeds - SP1, 10 mm - SP2) of 1.0% (SP1) and 0.5% (SP2), respectively. Ir(192)-brachytherapy presented MDR of 4.3945 × 10(-3) μGy h(-1) Bq(-1); and, 30% (SP1), and 20% (SP2). Therefore, seed's implant activities of 333 MBq (Ho(166)) and 259 GBq (Ir(192)) produced prescribed doses of 58 Gy (SP1; 5d) and 56 Gy (SP1, 5 fractions, 6 min), respectively. Breast Ho(166)-implants of 37-111 MBq are attractive due to the high dose rate near 6-10 mm from seeds, equivalent to Ir(192)-brachytherapy of 259 GBq (3 fractions, 6 min) providing similar dose in standard points at a week; however, with spatial dose distribution better confined. The seed positioning can be adjusted for controlling the breast tumor, in stages I and II, in flat and deep tumors, without any breast volumetric limitation.

  2. Solar panel cleaning robot

    NASA Astrophysics Data System (ADS)

    Nalladhimmu, Pavan Kumar Reddy; Priyadarshini, S.

    2018-04-01

    As the demand of electricity is increasing, there is need to using the renewable sources to produce the energy at present of power shortage, the use of solar energy could be beneficial to great extent and easy to get the maximum efficiency. There is an urgent in improving the efficiency of solar power generation. Current solar panels setups take a major power loss when unwanted obstructions cover the surface of the panels. To make solar energy more efficiency of solar array systems must be maximized efficiency evaluation of PV panels, that has been discussed with particular attention to the presence of dust on the efficiency of the PV panels have been highlighted. This paper gives the how the solar panel cleaning system works and designing of the cleaning system.

  3. What Next After Ho Chi Minh?

    DTIC Science & Technology

    1966-04-08

    Propagands Department; Nguyen Chi Thanh, protege of Truong Chinh ; Nguyen Duy Trinh; and Le Duc Thoo The pro-Soviet faction consists of Pham Van Dong...Communist" "Pro-Soviet" Ho Chi Minh Le Duan Truong Chinh Pham Van Dong Pham Hung General Giap Le Duc Tho Nguyen Chi Thanh Nguyen Duy Trinh Le Thanh Nghi...0 o . 15 The contenders. 0 . . . .0.0 28 4a THE LINE-UP 0 * a 0 * * 0 0 31 The lessor three - Hoang Van Hoan, Le Duc Tho, Le Thanh Nghi o .* 0 * * 0

  4. Lightweight, Thermally Insulating Structural Panels

    NASA Technical Reports Server (NTRS)

    Eisen, Howard J.; Hickey, Gregory; Wen, Liang-Chi; Layman, William E.; Rainen, Richard A.; Birur, Gajanana C.

    1996-01-01

    Lightweight, thermally insulating panels that also serve as structural members developed. Honeycomb-core panel filled with low-thermal-conductivity, opacified silica aerogel preventing convection and minimizes internal radiation. Copper coating on face sheets reduces radiation. Overall thermal conductivities of panels smaller than state-of-art commercial non-structurally-supporting foam and fibrous insulations. On Earth, panels suitable for use in low-air-pressure environments in which lightweight, compact, structurally supporting insulation needed; for example, aboard high-altitude aircraft or in partially evacuated panels in refrigerators.

  5. Edaravone Improves Septic Cardiac Function by Inducing an HIF-1α/HO-1 Pathway

    PubMed Central

    He, Chao; Zhang, Wei; Li, Suobei; Ruan, Wei; Xu, Junmei

    2018-01-01

    Septic myocardial dysfunction remains prevalent and raises mortality rate in patients with sepsis. During sepsis, tissues undergo tremendous oxidative stress which contributes critically to organ dysfunction. Edaravone, a potent radical scavenger, has been proved beneficial in ischemic injuries involving hypoxia-inducible factor- (HIF-) 1, a key regulator of a prominent antioxidative protein heme oxygenase- (HO-) 1. However, its effect in septic myocardial dysfunction remains unclarified. We hypothesized that edaravone may prevent septic myocardial dysfunction by inducing the HIF-1/HO-1 pathway. Rats were subjected to cecal ligation and puncture (CLP) with or without edaravone infusion at three doses (50, 100, or 200 mg/kg, resp.) before CLP and intraperitoneal injection of the HIF-1α antagonist, ME (15 mg/kg), after CLP. After CLP, rats had cardiac dysfunction, which was associated with deformed myocardium, augmented lipid peroxidation, and increased myocardial apoptosis and inflammation, along with decreased activities of catalase, HIF-1α, and HO-1 in the myocardium. Edaravone pretreatment dose-dependently reversed the changes, of which high dose most effectively improved cardiac function and survival rate of septic rats. However, inhibition of HIF-1α by ME demolished the beneficial effects of edaravone at high dose, reducing the survival rate of the septic rats without treatments. Taken together, edaravone, by inducing the HIF-1α/HO-1 pathway, suppressed oxidative stress and protected the heart against septic myocardial injury and dysfunction. PMID:29765498

  6. Protectin DX suppresses hepatic gluconeogenesis through AMPK-HO-1-mediated inhibition of ER stress.

    PubMed

    Jung, Tae Woo; Kim, Hyung-Chun; Abd El-Aty, A M; Jeong, Ji Hoon

    2017-06-01

    Several studies have shown that protectins, which are ω-3 fatty acid-derived proresolution mediators, may improve insulin resistance. Recently, protectin DX (PDX) was documented to attenuate insulin resistance by stimulating IL-6 expression in skeletal muscle, thereby regulating hepatic gluconeogenesis. These findings made us investigate the direct effects of PDX on hepatic glucose metabolism in the context of diabetes. In the current study, we show that PDX regulates hepatic gluconeogenesis in a manner distinct from its indirect glucoregulatory activity via IL-6. We found that PDX stimulated AMP-activated protein kinase (AMPK) phosphorylation, thereby inducing heme oxygenase 1 (HO-1) expression. This induction blocked hepatic gluconeogenesis by suppressing endoplasmic reticulum (ER) stress in hepatocytes under hyperlipidemic conditions. These effects were significantly dampened by silencing AMPK or HO-1 expression with small interfering RNA (siRNA). We also demonstrated that administration of PDX to high fat diet (HFD)-fed mice resulted in increased hepatic AMPK phosphorylation and HO-1 expression, whereas hepatic ER stress was substantially attenuated. Furthermore, PDX treatment suppressed the expression of gluconeogenic genes, thereby decreasing blood glucose levels in HFD-fed mice. In conclusion, our findings suggest that PDX inhibits hepatic gluconeogenesis via AMPK-HO-1-dependent suppression of ER stress. Thus, PDX may be an effective therapeutic target for the treatment of insulin resistance and type 2 diabetes through the regulation of hepatic gluconeogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Optical spectroscopy of low-phonon Ho3+ doped BaY2F8 single crystal

    NASA Astrophysics Data System (ADS)

    Li, Chun; Zeng, Fanming; Lin, Hai; Zheng, Dongyang; Yang, Xiaodong; Liu, Wang; Liu, Jinghe

    2014-12-01

    The Ho:BaY2F8 crystal was grown by Czochralski method. The crystal phase structure and absorption spectra were tested, the absorption peak exists near 899 nm, the absorption cross section was 1.27 × 10-21 cm2. The emission spectra of crystals in the vicinity of 2 and 3.9 μm were measured, the 2 μm near infrared light induced by 5I7 → 5I8 transition of Ho3+ ions was observed, as well as the fluorescence output at 3.9 μm (5I5 → 5I6), emission cross section at 3.9 μm was calculated to be 0.86 × 10-21 cm2. We suppose that the Ho:BaY2F8 crystal has a large application prospect for the 2-4 μm wavelength near infrared laser.

  8. Glass/Epoxy Door Panel for Automobiles

    NASA Technical Reports Server (NTRS)

    Bauer, J. L. JR.

    1985-01-01

    Lightweight panel cost-effective. Integrally-molded intrusion strap key feature of composite outer door panel. Strap replaces bulky and heavy steel instrusion beam of conventional door. Standard steel inner panel used for demonstration purposes. Door redesigned to exploit advantages of composite outer panel thinner. Outer panel for automobilie door, made of glass/epoxy composite material, lighter than conventional steel door panel, meets same strength requirements, and less expensive.

  9. Lightweight composites for modular panelized construction

    NASA Astrophysics Data System (ADS)

    Vaidya, Amol S.

    Rapid advances in construction materials technology have enabled civil engineers to achieve impressive gains in the safety, economy, and functionality of structures built to serve the common needs of society. Modular building systems is a fast-growing modern, form of construction gaining recognition for its increased efficiency and ability to apply modern technology to the needs of the market place. In the modular construction technique, a single structural panel can perform a number of functions such as providing thermal insulation, vibration damping, and structural strength. These multifunctional panels can be prefabricated in a manufacturing facility and then transferred to the construction site. A system that uses prefabricated panels for construction is called a "panelized construction system". This study focuses on the development of pre-cast, lightweight, multifunctional sandwich composite panels to be used for panelized construction. Two thermoplastic composite panels are proposed in this study, namely Composite Structural Insulated Panels (CSIPs) for exterior walls, floors and roofs, and Open Core Sandwich composite for multifunctional interior walls of a structure. Special manufacturing techniques are developed for manufacturing these panels. The structural behavior of these panels is analyzed based on various building design codes. Detailed descriptions of the design, cost analysis, manufacturing, finite element modeling and structural testing of these proposed panels are included in this study in the of form five peer-reviewed journal articles. The structural testing of the proposed panels involved in this study included flexural testing, axial compression testing, and low and high velocity impact testing. Based on the current study, the proposed CSIP wall and floor panels were found satisfactory, based on building design codes ASCE-7-05 and ACI-318-05. Joining techniques are proposed in this study for connecting the precast panels on the construction

  10. Establishing the Dependence of [HO2]/[OH] on Temperature, Halogen Loading, O3, and NO(x) Based on in Situ Measurements from the NASA ER-2

    NASA Technical Reports Server (NTRS)

    Lanzendorf, E. J.; Hanisco, T. F.; Wennberg, P. O.; Cohen, R. C.; Stimpfle, R. M.; Anderson, J. G.; Gao, R. S.; Margitan, J. J.; Bui, T. P.

    2001-01-01

    In situ observations of OH and HO2 from the Airborne Southern Hemisphere Ozone Experiment/Measurements for Assessing the Effects of Stratospheric Aircraft (ASHOE/MAESA), Stratospheric TRacers of Atmospheric Transport (STRAT), and Polar Ozone Loss in the Arctic Region in Summer (POLARIS) NASA ER-2 field campaigns are used to examine the partitioning of HO(x) in the lower stratosphere (tropopause to approx.21 km) and upper troposphere (approx.10 km to tropopause). These measurements span a latitude range from 70degS to 90degN and a variety of atmospheric conditions as a result of seasonal changes and altitude. The response of the observed [HO2]/[OH] to changes in temperature, [03], [CO], [NO], [CIO], and [BrO] is investigated. The measured ratio is accurately described (approx.+/-10%) by a steady-state model constrained by the measured mixing ratios of O3, CO, NO, CIO, and BrO, where the model is valid for conditions of HO(x) cycling much faster than HO(x) production and loss. The concentration of HO2 depends on [OH], which, to first order, has been observed to be a simple function of the solar zenith angle in the lower stratosphere. The partitioning between OH and HO2 is controlled by the local chemistry between the HO, radicals and O3, CO, NO, CIO, and BrO. The response of [HO(x)] to changes in [NO(x)] and [O3] is demonstrated. Further observations are necessary to illustrate the response of HO(x) to changes in halogen concentrations. A quantitative understanding of [HO2]/[OH] is important, since many of the reactions that control this ratio are directly involved in catalytic removal of O3 in the lower stratosphere and production of O3 in the upper troposphere.

  11. Spectroscopic analysis and efficient diode-pumped 2.0 μm emission in Ho3+/Tm3+ codoped fluoride glass

    NASA Astrophysics Data System (ADS)

    Tian, Ying; Jing, Xufeng; Xu, Shiqing

    2013-11-01

    Intense 2.0 μm emission has been obtained in Ho3+/Tm3+ codoped ZBLAY glass pumped by common laser diode. Three intensity parameters and radiative properties have been determined from the absorption spectrum based on the Judd-Ofelt theory. The 2 μm emission characteristics and the energy transfer mechanism upon excitation of a conventional 800 nm laser diode are investigated. Efficient Tm3+ to Ho3+ energy transfer processes have been observed in present glass and investigated using steady-state and time-resolved optical spectroscopy measurement. The energy transfer microscopic parameter has been calculated with the Inokuti-Hirayama and Förster-Dexter models. High quantum efficiency of 2 μm emission (80.35%) and large energy transfer coefficient from Tm3+ to Ho3+ indicates this Ho3+/Tm3+ codoped ZBLAY glass is a promising material for 2.0 μm laser.

  12. Production and characterization of soluble human TNFRI-Fc and human HO-1(HMOX1) transgenic pigs by using the F2A peptide.

    PubMed

    Park, Sol Ji; Cho, Bumrae; Koo, Ok Jae; Kim, Hwajung; Kang, Jung Taek; Hurh, Sunghoon; Kim, Su Jin; Yeom, Hye Jung; Moon, Joonho; Lee, Eun Mi; Choi, Ji Yei; Hong, Ju Ho; Jang, Goo; Hwang, Joing-Ik; Yang, Jaeseok; Lee, Byeong Chun; Ahn, Curie

    2014-06-01

    Generation of transgenic pigs for xenotransplantation is one of the most promising technologies for resolving organ shortages. Human heme oxygenase-1 (hHO-1/HMOX1) can protect transplanted organs by its strong anti-oxidative, anti-apoptotic, and anti-inflammatory effects. Soluble human TNFRI-Fc (shTNFRI-Fc) can inhibit the binding of human TNF-α (hTNF-α) to TNF receptors on porcine cells, and thereby, prevent hTNF-α-mediated inflammation and apoptosis. Herein, we successfully generated shTNFRI-Fc-F2A-HA-hHO-1 transgenic (TG) pigs expressing both shTNFRI-Fc and hemagglutinin-tagged-human heme oxygenase-1 (HA-hHO-1) by using an F2A self-cleaving peptide. shTNFRI-Fc and HA-hHO-1 transgenes containing the F2A peptide were constructed under the control of the CAG promoter. Transgene insertion and copy number in the genome of transgenic pigs was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Expressions of shTNFRI-Fc and HA-hHO-1 in TG pigs were confirmed using PCR, RT-PCR, western blot, ELISA, and immunohistochemistry. shTNFRI-Fc and HA-hHO-1 were expressed in various organs, including the heart, lung, and spleen. ELISA assays detected shTNFRI-Fc in the sera of TG pigs. For functional analysis, fibroblasts isolated from a shTNFRI-Fc-F2A-HA-hHO-1 TG pig (i.e., #14; 1 × 10(5) cells) were cultured with hTNF-α (20 ng/mL) and cycloheximide (10 μg/mL). The viability of shTNFRI-Fc-F2A-HA-hHO-1 TG pig fibroblasts was significantly higher than that of the wild type (wild type vs. shTNFRI-Fc-F2A-HA-hHO-1 TG at 24 h, 31.6 ± 3.2 vs. 60.4 ± 8.3 %, respectively; p < 0.05). Caspase-3/-7 activity of the shTNFRI-Fc-F2A-HA-hHO-1 TG pig fibroblasts was lower than that of the wild type pig fibroblasts (wild type vs. shTNFRI-Fc-F2A-HA-hHO-1 TG at 12 h, 812,452 ± 113,078 RLU vs. 88,240 ± 10,438 RLU, respectively; p < 0.05). These results show that shTNFRI-Fc and HA-hHO-1 TG pigs generated by the F2A self-cleaving peptide express both sh

  13. Decay of the neutron-rich isotope 171Ho and the identification of 169Dy

    NASA Astrophysics Data System (ADS)

    Chasteler, R. M.; Nitschke, J. M.; Firestone, R. B.; Vierinen, K. S.; Wilmarth, P. A.

    1990-10-01

    Neutron-rich rare-earth isotopes were produced in multinucleon transfer reactions between 170Er ions and natW targets. On-line mass separation was used together with β- and γ-ray spectroscopy in these studies. At mass A=169, the heaviest known dysprosium isotope, 39(8) s,169Dy, was identified. It was observed to β- decay to the ground state of 169Ho or through a level at 1578 keV. In the A=171 mass chain, a partial decay scheme for 55(3)-s 171Ho was determined.

  14. Aerospace Safety Advisory Panel

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Aerospace Safety Advisory Panel (ASAP) provided oversight on the safety aspects of many NASA programs. In addition, ASAP undertook three special studies. At the request of the Administrator, the panel assessed the requirements for an assured crew return vehicle (ACRV) for the space station and reviewed the organization of the safety and mission quality function within NASA. At the behest of Congress, the panel formed an independent, ad hoc working group to examine the safety and reliability of the space shuttle main engine. Section 2 presents findings and recommendations. Section 3 consists of information in support of these findings and recommendations. Appendices A, B, C, and D, respectively, cover the panel membership, the NASA response to the findings and recommendations in the March 1992 report, a chronology of the panel's activities during the reporting period, and the entire ACRV study report.

  15. Presence of parimagnetism in HoCo2 under hydrostatic pressure

    NASA Astrophysics Data System (ADS)

    Valenta, Jaroslav; Prchal, Jiri; Kratochvilova, Marie; Misek, Martin; Sechovsky, Vladimir; Charles University in Prague, DCMP Team

    2013-06-01

    HoCo2 belongs to a group of RECo2 compounds (RE = rare earth metal) which were previously studied mostly due to presence of two types of magnetism - the localized RE magnetic moment and the Co moment originating in the splitting of the Co 3d subbands. The corresponding RE and Co magnetic sublattices are both ferromagnetic and antiparallel to each other for RE ∈ (Gd..Tm) below TC. In 2007 Herrero-Albillos et al. published experimental evidences of the Co moments surviving in paramagnetic state above TC in ErCo2. The surviving Co magnetic moments form small (ferromagnetic) clusters coupled antiparallel to the nearest RE magnetic moments in the paramagnetic state. These antiparallel short-range Co-Er moment correlations at T >TC are denoted as parimagnetism. Above a characteristic temperature Tf (observed in the AC magnetic susceptibility data as a tiny anomaly) the Co magnetic moment turns to the same direction as Er magnetic moment. The phenomenon of parimagnetism has been recently confirmed for HoCo2. In 2011 Bonilla at al. presented results from μ SR experiment on ErCo2. Results of the μ SR experiment show the presence of Co magnetic clusters up to temperature T*>Tf. We present experimental results AC susceptibility measurements for HoCo2 under hydrostatic pressure up to 3 GPa and μ SR data under hydrostatic pressure up to 2 GPa. The results will be discussed in terms of corresponding variations of the hierarchy inter- and intra-sublattice exchange interactions.

  16. An Efficient Single Frequency Ho:YLF Laser for IPDA Lidar Applications

    NASA Technical Reports Server (NTRS)

    Yu, J.; Bai, Y.; Wong, T.; Reithmeier, K.; Petros, M.

    2016-01-01

    A highly efficient, versatile, single frequency 2-micron pulsed laser can be used in a pulsed Differential Absorption Lidar (DIAL) / Integrated Path Differential Absorption (IPDA) instrument to make precise, high-resolution measurements to investigate sources and sinks of CO2. For a direct detection IPDA lidar, the desired 2 ?m Ho:YLF laser should generate 30-40 mJ pulses at the repetition rate of 100 to 200 Hz, with short pulse length (<100 ns) and better than 2% wall plug efficiency. A Tm fiber laser in-band pumped Ho:YLF laser has been developed to meet this technical challenge. This Ho:YLF laser is designed in a four mirror ring resonator with bow tie configuration, which helps to obtain high beam quality. It is end-pumped by a 40 W linearly polarized Tm fiber laser at 1.94µm. The resonator length is 1.10 meters with output coupler reflectivity at 45%. The laser crystal size is 3 x 3 x 60 mm (w, h, l) with a doping concentration of 0.5% Holmium. The laser beam and pump beam are mode-matched in the active medium. Thus, the pump and laser beams have the same confocal parameters. Mode-matching is also helpful for operating the laser in a single transverse mode. The laser beam waist is slightly less than 0.5 mm at the center of the laser crystal. Based on quasi-four level modeling, pump absorption and saturation depend on laser intensity. Laser amplification and saturation also depend on the pump intensity in the crystal. The laser is injection seeded to obtain the single frequency required by an IPDA lidar measurement. The seed beam is entered into the resonator through an output coupler. The laser is mounted on a water cooled optical bench for stable and reliable operation. The size of the optical bench is 22.16 x 9.20 x 1.25 inches. It is stiffened so that the laser can be operated in any orientation of the optical bench. This packaged Ho:YLF laser is designed for either mobile trailer or airborne platform operation. The engineering prototype Ho:YLF laser has

  17. Flexible optical panel

    DOEpatents

    Veligdan, James T.

    2001-01-01

    A flexible optical panel includes laminated optical waveguides, each including a ribbon core laminated between cladding, with the core being resilient in the plane of the core for elastically accommodating differential movement thereof to permit winding of the panel in a coil.

  18. Make Your Own Solar Panel.

    ERIC Educational Resources Information Center

    Suzuki, David

    1992-01-01

    Presents an activity in which students make a simulated solar panel to learn about the principles behind energy production using solar panels. Provides information about how solar panels function to produce energy. (MCO)

  19. Pro-Inflammatory and Pro-Oxidant Status of Pancreatic Islet In Vitro Is Controlled by TLR-4 and HO-1 Pathways

    PubMed Central

    Vivot, Kevin; Langlois, Allan; Bietiger, William; Dal, Stéphanie; Seyfritz, Elodie; Pinget, Michel; Jeandidier, Nathalie; Maillard, Elisa; Gies, Jean-Pierre; Sigrist, Séverine

    2014-01-01

    Since their isolation until implantation, pancreatic islets suffer a major stress leading to the activation of inflammatory reactions. The maintenance of controlled inflammation is essential to preserve survival and function of the graft. Identification and targeting of pathway(s) implicated in post-transplant detrimental inflammatory events, is mandatory to improve islet transplantation success. We sought to characterize the expression of the pro-inflammatory and pro-oxidant mediators during islet culture with a focus on Heme oxygenase (HO-1) and Toll-like receptors-4 signaling pathways. Rat pancreatic islets were isolated and pro-inflammatory and pro-oxidant status were evaluated after 0, 12, 24 and 48 hours of culture through TLR-4, HO-1 and cyclooxygenase-2 (COX-2) expression, CCL-2 and IL-6 secretion, ROS (Reactive Oxygen Species) production (Dihydroethidine staining, DHE) and macrophages migration. To identify the therapeutic target, TLR4 inhibition (CLI-095) and HO-1 activation (cobalt protoporphyrin,CoPP) was performed. Activation of NFκB signaling pathway was also investigated. After isolation and during culture, pancreatic islet exhibited a proinflammatory and prooxidant status (increase levels of TLR-4, COX-2, CCL-2, IL-6, and ROS). Activation of HO-1 or inhibition of TLR-4 decreased inflammatory status and oxidative stress of islets. Moreover, the overexpression of HO-1 induced NFκB phosphorylation while the inhibition of TLR-4 had no effect NFκB activation. Finally, inhibition of pro-inflammatory pathway induced a reduction of macrophages migration. These data demonstrated that the TLR-4 signaling pathway is implicated in early inflammatory events leading to a pro-inflammatory and pro-oxidant status of islets in vitro. Moreover, these results provide the mechanism whereby the benefits of HO-1 target in TLR-4 signaling pathway. HO-1 could be then an interesting target to protect islets before transplantation. PMID:25343247

  20. Double Q-switch Ho:Sc2SiO5 laser by acousto-optic modulator combined with Cr2+:ZnSe saturable absorber

    NASA Astrophysics Data System (ADS)

    Yang, Xiao-tao; Zhang, Peng; Xie, Wen-qiang; Li, Lin-jun

    2018-01-01

    A double Q-switch (DQS) Ho:Sc2SiO5 laser modulated by a acousto-optic modulators (AOM) combined with a Cr2+:ZnSe saturable absorber (SA) was reported for the first time. The actively Q-switch (AQS) and passively Q-switch (PQS) were also studied. For the DQS mode, a maximum average output power of 2.49 W under the incident pump power of 12.5 W was obtained, corresponding to a slope efficiency of 24%. The characteristics of the DQS Ho:SSO laser versus different repetition frequencies (RF) of the AOM were researched. The maximum single-pulse energy of the DQS Ho:SSO laser was calculated to 1.98 mJ. The maximum peak power of the DQS Ho:SSO laser was 49.5 kW. The output beam quality factor M2 of DQS Ho:SSO laser was measured to be 1.15 with the highest peak power by knife-edge method at different positions.

  1. Aerospace Safety Advisory Panel

    NASA Technical Reports Server (NTRS)

    1998-01-01

    During 1997, the Aerospace Safety Advisory Panel (ASAP) continued its safety reviews of NASA's human space flight and aeronautics programs. Efforts were focused on those areas that the Panel believed held the greatest potential to impact safety. Continuing safe Space Shuttle operations and progress in the manufacture and testing of primary components for the International Space Station (ISS) were noteworthy. The Panel has continued to monitor the safety implications of the transition of Space Shuttle operations to the United Space Alliance (USA). One area being watched closely relates to the staffing levels and skill mix in both NASA and USA. Therefore, a section of this report is devoted to personnel and other related issues that are a result of this change in NASA's way of doing business for the Space Shuttle. Attention will continue to be paid to this important topic in subsequent reports. Even though the Panel's activities for 1997 were extensive, fewer specific recommendations were formulated than has been the case in recent years. This is indicative of the current generally good state of safety of NASA programs. The Panel does, however, have several longer term concerns that have yet to develop to the level of a specific recommendation. These are covered in the introductory material for each topic area in Section 11. In another departure from past submissions, this report does not contain individual findings and recommendations for the aeronautics programs. While the Panel devoted its usual efforts to examining NASA's aeronautic centers and programs, no specific recommendations were identified for inclusion in this report. In lieu of recommendations, a summary of the Panel's observations of NASA's safety efforts in aeronautics and future Panel areas of emphasis is provided. With profound sadness the Panel notes the passing of our Chairman, Paul M. Johnstone, on December 17, 1997, and our Staff Assistant, Ms. Patricia M. Harman, on October 5, 1997. Other

  2. Color tunable emission through energy transfer from Yb3+ co-doped SrSnO3: Ho3+ perovskite nano-phosphor

    NASA Astrophysics Data System (ADS)

    Jain, Neha; Singh, Rajan Kr.; Sinha, Shriya; Singh, R. A.; Singh, Jai

    2018-04-01

    First time color tunable lighting observed from Ho3+ and Yb3+ co-doped SrSnO3 perovskite. Down-conversion and up-conversion (UC) photoluminescence emission spectra were recorded to understand the whole mechanism of energy migration between Ho3+ and Yb3+ ions. The intensity of green and red emission varies with Yb3+ doping which causes multicolour emissions from nano-phosphor. The intensity of UC red emission (654 nm) obtained from 1 at.% Ho3+ and 3 at.% Yb3+ co-doped nano-phosphor is nine times higher than from 1 at.% Ho3+ doped SrSnO3 nano-phosphor. Enhanced brightness of 654 nm in UC process belongs in biological transparency window so that it might be a promising phosphor in the bio-medical field. Moreover, for the other Yb3+ co-doped nano-phosphor, Commission Internationale de l'Éclairage chromaticity co-ordinates were found near the white region and their CCT values lie in the range 4900-5100 K indicating cool white. Decay time was measured for 545 nm emission of Ho3+ ion found in 7.652 and 8.734 µs at 355 nm excitation. The variation in lifetime was observed in ascending order with increasing Yb3+ concentration which supports PL emission spectra observation that with increasing Yb3+ concentration, rate of transition has changed. These studies reveal that Ho3+ and Yb3+ co-doped phosphor is useful for fabrication of white LEDs.

  3. Treatment of hyperplastic inferior nasal turbinates by means of a Ho:YAG laser

    NASA Astrophysics Data System (ADS)

    Sroka, Ronald; Leunig, Andreas; Janda, P.; Rosler, P.; Grevers, G.; Baumgartner, Reinhold

    1999-06-01

    Although the successful use of the Ho:YAG laser in nasal turbinate surgery had been reported no clinical study had been performed to assess the clinical outcome in longterm. By means of a pulsed Ho:YAG laser emitting at λ=2080nm (1J/pulse, 3-8 Hz) 57 patients suffering from nasal obstruction due to allergic rhinitis and vasomotoric rhinitis were treated under local anesthesia. The study was conducted by standardized questionnaire, photo documentation, allergy test, mucocilliar test, rhinomanometry, radiology and histology. Within 2 weeks after laser treatment a significant improvement of nasal airflow correlating to the extent of the ablated turbinate tissue could be determined. This effect lasted up until 1 year post treatment resulting in an improved quality of life in more than 80 percent of the patients. Side effects like nasal dryness and pain were rare (<4%), no immediate complications were observed. The total treatment time takes 3-8 min and nasal packing was not necessary after the laser procedure. In conclusion Ho:YAG laser treatment can be performed as an outpatient procedure under local anesthesia with excellent ablation of soft tissue in a short treatment time with promising results.

  4. Tunable diode laser measurements of HO2NO2 absorption coefficients near 12.5 microns

    NASA Technical Reports Server (NTRS)

    May, R. D.; Molina, L. T.; Webster, C. R.

    1988-01-01

    A tunable diode laser spectrometer has been used to measure absorption coefficients of peroxynitric acid (HO2NO2) near the 803/cm Q branch. HO2NO2 concentrations in a low-pressure flowing gas mixture were determined from chemical titration procedures and UV absorption spectroscopy. The diode laser measured absorption coefficients, at a spectral resolution of better than 0.001/cm, are about 10 percent larger than previous Fourier transform infrared measurements made at a spectral resolution of 0.06/cm.

  5. Heat pipe thermal conditioning panel

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.; Loose, J. D.; Mccoy, K. E.

    1974-01-01

    Thermal control of electronic hardware and experiments on future space vehicles is critical to proper functioning and long life. Thermal conditioning panels (cold plates) are a baseline control technique in current conceptual studies. Heat generating components mounted on the panels are typically cooled by fluid flowing through integral channels within the panel. However, replacing the pumped fluid coolant loop within the panel with heat pipes offers attractive advantages in weight, reliability, and installation. This report describes the development and fabrication of two large 0.76 x 0.76 m heat pipe thermal conditioning panels to verify performance and establish the design concept.

  6. Comparative analysis of luminescent properties of germanate glass and double-clad optical fibers co-doped with Yb3+/Ho3+ ions

    NASA Astrophysics Data System (ADS)

    Pietrzycki, Marcin; Kochanowicz, Marcin; Romańczuk, Patryk; Żmojda, Jacek; Miluski, Piotr; Ragiń, Tomasz; Jeleń, Piotr; Sitarz, Maciej; Dorosz, Dominik

    2016-09-01

    The 2 μm and visible emission of low phonon (805 cm-1) germanate glasses and double - clad optical fiber co-doped with 0.7Yb2O3/(0.07-0.7)Ho2O3 ions have been investigated. Luminescence at 2 μm corresponding to Ho3+: 5I7 → 5I8 as well as upconversion luminescence in the visible spectral range corresponding to the Ho3+: 5S2(5F4)→5I8 (545 nm), and Ho3+: 5F5→5I8 (655 nm) transition, respectively were obtained. The optimization of the acceptor content and donor-acceptor ratio were conducted with the purpose of maximizing the luminescence intensity. The highest luminescence intensity in both spectral range was obtained in glass co-doped with 0.7Yb2O3/0.15 Ho2O3. Despite relatively small effective absorption coefficient of the optical fiber comparative analysis of luminescent properties of fabricated glasses (further core) and double - clad optical fiber showed significant contribution of reabsorption process of emitted ASE signal.

  7. Solar panel parallel mounting configuration

    NASA Technical Reports Server (NTRS)

    Mutschler, Jr., Edward Charles (Inventor)

    1998-01-01

    A spacecraft includes a plurality of solar panels interconnected with a power coupler and an electrically operated device to provide power to the device when the solar cells are insolated. The solar panels are subject to bending distortion when entering or leaving eclipse. Spacecraft attitude disturbances are reduced by mounting each of the solar panels to an elongated boom made from a material with a low coefficient of thermal expansion, so that the bending of one panel is not communicated to the next. The boom may be insulated to reduce its bending during changes in insolation. A particularly advantageous embodiment mounts each panel to the boom with a single mounting, which may be a hinge. The single mounting prevents transfer of bending moments from the panel to the boom.

  8. Titanium Honeycomb Panel Testing

    NASA Technical Reports Server (NTRS)

    Richards, W. Lance; Thompson, Randolph C.

    1996-01-01

    Thermal-mechanical tests were performed on a titanium honeycomb sandwich panel to experimentally validate the hypersonic wing panel concept and compare test data with analysis. Details of the test article, test fixture development, instrumentation, and test results are presented. After extensive testing to 900 deg. F, non-destructive evaluation of the panel has not detected any significant structural degradation caused by the applied thermal-mechanical loads.

  9. Luminescence properties of long-lasting phosphor SrMg2(PO4)2:Eu2+, Ho3+, Zr4+

    NASA Astrophysics Data System (ADS)

    Tang, Wei; Wang, Mingwen; Lin, Wei; Ye, Yaping; Wu, Xue

    2016-12-01

    Novel long lasting phosphors SrMg2(PO4)2:Eu2+, SrMg2(PO4)2:Eu2+, Zr4+, SrMg2(PO4)2:Eu2+, Ho3+ and SrMg2(PO4)2:Eu2+, Ho3+, Zr4+ were synthesized by conventional solid-state reaction method. The luminescent properties were systematically characterized by X-ray diffraction, photoluminescent excitation and emission spectra, as well as thermoluminescence spectrum and decay curves. The XRD patterns indicated that the samples belonged to monoclinic phase and co-doping Eu2+, Ho3+ and Zr4+ ions had no effect on the basic crystal structure. These phosphors emitting purplish blue light is related to the characteristic emission of Eu2+. The afterglow time of Eu2+ activated SrMg2(PO4)2 can be greatly enhanced by the co-doping of Ho3+, Zr4+. After the 365 nm UV light excitation source switching off, the Sr0.92Mg1.95(PO4)2:Eu2+0.01, Zr4+0.05, Ho3+0.07 phosphorescence can be observed for more than 1013 s in the limit of light perception of dark-adapted human eyes (0.32 mcd/m2). Different kinds of TL peaks at 423, 448 and 473 K have appeared, and traps densities have increased compared with the Eu2+ single doped SrMg2(PO4)2 phosphor. By analyzing the TL curve the depths of traps were calculated to be 0.846, 0.896 and 0.946 eV, respectively, which suggested that the co-doping of Ho3+, Zr4+ improved the electron storage ability of material. Besides, the mechanism was discussed in this report.

  10. A measurement of the vibrational band strength for the v3 band of the HO2 radical

    NASA Technical Reports Server (NTRS)

    Zahniser, M. S.; Stanton, A. C.

    1984-01-01

    Laboratory measurements of the v(3) band strength of HO2 using a tunable diode laser to measure the absorption strength of a vibration-rotation line in the P branch near 1080/cm are reported. The HO2 is generated in a discharge-flow system by reaction of fluorine atoms with excess H2O2: F + H2O2 - HO2 + HF. The HO2 concentration is determined from measurements of F-atom concentrations using both chemical titration with Cl2 and tunable diode laser absorption by the F-atom spin-orbit transition near 404/cm. The experimental data are consistent with a value of k(3) = (1.6 + or - 0.3) x 10 to the 12th cu cm/s and a ratio k(4)/k(1) = 1.0 + or - 0.4. The line strength for the 6(15) - 7(16)F(1) transition is 2.9 x 10 to the -21 sq cm/molecule/cm, which corresponds to a v(3) band strength of 35 + or - 9/sq cm/(STP atm). This value is a factor of 1.6 to 6 lower than previous ab initio calculations.

  11. Logarithmic entropy of Kehagias-Sfetsos black hole with self-gravitation in asymptotically flat IR modified Hořava gravity

    NASA Astrophysics Data System (ADS)

    Liu, Molin; Lu, Junwang

    2011-05-01

    Motivated by recent logarithmic entropy of Hořava-Lifshitz gravity, we investigate Hawking radiation for Kehagias-Sfetsos black hole from tunneling perspective. After considering the effect of self-gravitation, we calculate the emission rate and entropy of quantum tunneling by using Kraus-Parikh-Wilczek method. Meanwhile, both massless and massive particles are considered in this Letter. Interestingly, two types tunneling particles have the same emission rate Γ and entropy Sb whose analytical formulae are Γ=exp[π(rin2-rout2)/2+π/αln rin/rout] and Sb=A/4+π/αln(A/4), respectively. Here, α is the Hořava-Lifshitz field parameter. The results show that the logarithmic entropy of Hořava-Lifshitz gravity could be explained well by the self-gravitation, which is totally different from other methods. The study of this semiclassical tunneling process may shed light on understanding the Hořava-Lifshitz gravity.

  12. VUV photoionization cross sections of HO2, H2O2, and H2CO.

    PubMed

    Dodson, Leah G; Shen, Linhan; Savee, John D; Eddingsaas, Nathan C; Welz, Oliver; Taatjes, Craig A; Osborn, David L; Sander, Stanley P; Okumura, Mitchio

    2015-02-26

    The absolute vacuum ultraviolet (VUV) photoionization spectra of the hydroperoxyl radical (HO2), hydrogen peroxide (H2O2), and formaldehyde (H2CO) have been measured from their first ionization thresholds to 12.008 eV. HO2, H2O2, and H2CO were generated from the oxidation of methanol initiated by pulsed-laser-photolysis of Cl2 in a low-pressure slow flow reactor. Reactants, intermediates, and products were detected by time-resolved multiplexed synchrotron photoionization mass spectrometry. Absolute concentrations were obtained from the time-dependent photoion signals by modeling the kinetics of the methanol oxidation chemistry. Photoionization cross sections were determined at several photon energies relative to the cross section of methanol, which was in turn determined relative to that of propene. These measurements were used to place relative photoionization spectra of HO2, H2O2, and H2CO on an absolute scale, resulting in absolute photoionization spectra.

  13. Simple sonochemical synthesis of Ho2O3-SiO2 nanocomposites as an effective photocatalyst for degradation and removal of organic contaminant.

    PubMed

    Zinatloo-Ajabshir, Sahar; Mortazavi-Derazkola, Sobhan; Salavati-Niasari, Masoud

    2017-11-01

    In this work, highly photocatalytically active Ho 2 O 3 -SiO 2 nanocomposites have been designed and applied for decomposition of methylene blue pollutant. Ho 2 O 3 -SiO 2 nanocomposites have been produced by new, quick and facile sonochemical process with the aid of tetramethylethylenediamine as a novel basic agent for the first time. The effect of the kind of basic agent, ultrasonic time and dosage of Ho source on the grain size, photocatalytic behavior and shape of the Ho 2 O 3 -SiO 2 nanocomposites have been evaluated for optimization the production condition. FESEM, EDX, FT-IR, DRS, XRD and TEM have been applied to characterize the as-produced Ho 2 O 3 -SiO 2 nanocomposites. Use of the as-produced Ho 2 O 3 -SiO 2 nanocomposites as photocatalyst via destruction of methylene blue pollutant under UV illumination has been compared. It was observed that SiO 2 has notable impact on catalytic activity of holmium oxide photocatalyst for destruction. Introducing of SiO 2 to holmium oxide can enhance destruction efficiency of holmium oxide to methylene blue pollutant under ultraviolet light. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Carbon kinetic isotope effect in the reaction of CH4 with HO

    NASA Technical Reports Server (NTRS)

    Davidson, J. A.; Cantrell, C. A.; Tyler, S. C.; Shetter, R. E.; Cicerone, R. J.

    1987-01-01

    The carbon kinetic isotope effect in the CH4 + HO reaction is measured experimentally and the use of carbon isotope ratios to diagnose atmospheric methane is examined. The chemical, photolysis, and analytical experimental conditions and procedures are described. It is determined that the CH4 + HO reaction has a carbon kinetic isotope effect of 1.010 + or 0.007 for k(12)k(13) (rate constants ratio) at 297 + or - 3 K. This value is compared with the data of Rust and Stevens (1980). Causes for the poor correlation between the data at high methane conversions are discussed. It is supposed that the difference between the k(12) and k(13) values is due to a difference in the activation energy of the two reactions.

  15. Are HO radicals produced in the reaction of O(3P) with 1-C4H8 ?

    NASA Technical Reports Server (NTRS)

    Luria, M.; Simonaitis, R.; Heicklen, J.

    1972-01-01

    The reaction of O(3P) with 1-C4H8 was examined in the presence of CO which scavenges HO radicals to produce CO2. From the CO2 quantum yield, an upper limit to the efficiency of HO production in the reaction of O(3P) with 1-C4H8 was found to be 0.020 at both 298 and 473 K.

  16. Totarol prevents neuronal injury in vitro and ameliorates brain ischemic stroke: Potential roles of Akt activation and HO-1 induction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Yuanxue; Xu, Xiaojun; Chang, Sai

    The natural product totarol, a phenolic diterpenoid and a major constituent isolated from the sap of Podocarpus totara, has been reported to have a potent antimicrobial activity. In this study, we determined whether totarol possessed an additional neuroprotective activity in vitro and in vivo. We found that totarol prevented glutamate- and oxygen and glucose deprivation-induced neuronal death in primary rat cerebellar granule neuronal cells and cerebral cortical neurons. Totarol increased Akt and GSK-3β phosphorylation, Nrf2 and heme oxygenase-1 (HO-1) protein expressions and suppressed oxidative stress by increasing GSH and SOD activities. The PI3K/Akt inhibitor LY294002 prevented totarol neuroprotective effect bymore » suppressing the totarol-induced changes in HO-1 expression and the activities of GSH and SOD. The HO-1 inhibitor ZnPPIX also prevented totarol-increased GSH and SOD activities. In a model of acute cerebral ischemic injury in Sprague–Dawley rats, produced by occlusion of the middle cerebral artery for 2 h followed by 22 h or 46 h of reperfusion, totarol significantly reduced infarct volume and improved the neurological deficit. In this model, totarol increased HO-1 expression and the activities of GSH and SOD. These observations suggest that totarol may be a novel activator of the Akt/HO-1 pathway protecting against ischemic stroke through reduction of oxidative stress. - Graphical abstract: It is unknown whether the natural product totarol has neuroprotective effects in vitro and in vivo. This study underscores that totarol prevents neuronal injury in vitro, not only by activating PI3K/Akt pathway, but also via induction of Nrf2, HO-1, GSH and SOD expressions. Totarol also ameliorated acute cerebral ischemic injury in a rat ischemic stroke model. The findings highlight that totarol may be exploited for protecting against ischemic stroke through Akt/HO-1 pathway. - Highlights: • Totarol protects glutamate- and OGD-induced neuronal injury in

  17. HO-1 inhibits IL-13-induced goblet cell hyperplasia associated with CLCA1 suppression in normal human bronchial epithelial cells.

    PubMed

    Mishina, Kei; Shinkai, Masaharu; Shimokawaji, Tadasuke; Nagashima, Akimichi; Hashimoto, Yusuke; Inoue, Yoriko; Inayama, Yoshiaki; Rubin, Bruce K; Ishigatsubo, Yoshiaki; Kaneko, Takeshi

    2015-12-01

    Mucus hypersecretion and goblet cell hyperplasia are common features that characterize asthma. IL-13 increases mucin (MUC) 5AC, the major component of airway mucus, in airway epithelial cells. According to the literature, IL-13 receptor activation leads to STAT6 activation and consequent induction of chloride channel accessory 1 (CLCA1) gene expression, associated with the induction of MUC5AC. Heme oxygenase-1 (HO-1) is an enzyme that catalyzes oxidation of heme to biliverdin, and has anti-inflammatory and anti-oxidant properties. We examined the effects of HO-1 on mucin production and goblet cell hyperplasia induced by IL-13. Moreover, we assessed the cell signaling intermediates that appear to be responsible for mucin production. Normal human bronchial epithelial (NHBE) cells were grown at air liquid interface (ALI) in the presence or absence of IL-13 and hemin, a HO-1 inducer, for 14 days. Protein concentration was analyzed using ELISA, and mRNA expression was examined by real-time PCR. Histochemical analysis was performed using HE staining, andWestern blotting was performed to evaluate signaling transduction pathway. Hemin (4 μM) significantly increased HO-1 protein expression (p b 0.01) and HO-1 mRNA expression (p b 0.001). IL-13 significantly increased goblet cells, MUC5AC protein secretion (p b 0.01) and MUC5AC mRNA (p b 0.001), and these were decreased by hemin by way of HO-1. Tin protoporphyrin (SnPP)-IX, a HO-1 inhibitor, blocked the effect of hemin restoring MUC5AC protein secretion (p b 0.05) and goblet cell hyperplasia. Hemin decreased the expression of CLCA1 mRNA (p b 0.05) and it was reversed by SnPP-IX, but could not suppress IL-13-induced phosphorylation of STAT6 or SAM pointed domain-containing ETS transcription factor (SPDEF) and Forkhead box A2 (FOXA2) mRNA expression. In summary, HO-1 overexpression suppressed IL-13-induced goblet cell hyperplasia and MUC5AC production, and involvement of CLCA1 in the mechanism was suggested.

  18. Characterization of docosahexaenoic acid (DHA)-induced heme oxygenase-1 (HO-1) expression in human cancer cells: the importance of enhanced BTB and CNC homology 1 (Bach1) degradation.

    PubMed

    Wang, Shuai; Hannafon, Bethany N; Wolf, Roman F; Zhou, Jundong; Avery, Jori E; Wu, Jinchang; Lind, Stuart E; Ding, Wei-Qun

    2014-05-01

    The effect of docosahexaenoic acid (DHA) on heme oxygenase-1 (HO-1) expression in cancer cells has never been characterized. This study examines DHA-induced HO-1 expression in human cancer cell model systems. DHA enhanced HO-1 gene expression in a time- and concentration-dependent manner, with maximal induction at 21 h of treatment. This induction of HO-1 expression was confirmed in vivo using a xenograft nude mouse model fed a fish-oil-enriched diet. The increase in HO-1 gene transcription induced by DHA was significantly attenuated by the antioxidant N-acetyl cysteine, suggesting the involvement of oxidative stress. This was supported by direct measurement of lipid peroxide levels after DHA treatment. Using a human HO-1 gene promoter reporter construct, we identified two antioxidant response elements (AREs) that mediate the DHA-induced increase in HO-1 gene transcription. Knockdown of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression compromised the DHA-induced increase in HO-1 gene transcription, indicating the importance of the Nrf2 pathway in this event. However, the nuclear protein levels of Nrf2 remained unchanged upon DHA treatment. Further studies demonstrated that DHA reduces nuclear Bach1 protein expression by promoting its degradation and attenuates Bach1 binding to the AREs in the HO-1 gene promoter. In contrast, DHA enhanced Nrf2 binding to the AREs without affecting nuclear Nrf2 expression levels, indicating a new cellular mechanism that mediates DHA's induction of HO-1 gene transcription. To our knowledge, this is the first characterization of DHA-induced HO-1 expression in human malignant cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Immobilization of Eu and Ho from synthetic acid mine drainage by precipitation with Fe and Al (hydr)oxides.

    PubMed

    Barcelos, Gisely S; Veloso, Renato Welmer; de Mello, Jaime W V; Gasparon, Massimo

    2018-04-30

    Use of lime to mitigate acid mine drainage is, in general, accompanied by precipitation of iron (Fe) and aluminium (Al) (hydr)oxides which may increase the removal of trace elements from water. This work aimed to evaluate the precipitation of Fe/Al (hydr)oxides to remove rare earth elements (REE) from contaminated water and the stability of precipitates. Two sets of 60-day syntheses were carried out using different Fe/Al/REE molar ratios, for europium (Eu) and holmium (Ho). The pH was periodically adjusted to 9.0, and the stability of the resulting precipitates was evaluated by water-soluble and BCR extractable phases, namely (1) acid soluble, extracted by 0.11 mol L -1 acetic acid; (2) reducible, extracted with 0.5 mol L -1 hydroxylamine hydrochloride; and (3) oxidisable, extracted with 8.8 mol L -1 hydrogen peroxide efficiencies of the water treatments for both Eu and Ho that were higher than 99.9% irrespective to the Fe/Al/REE molar ratios. Water-soluble phases of Eu and Ho were lower than 0.01% of the total contents in the precipitates. Recoveries from precipitates by Bureau Communautaire de Référence (BCR) sequential extractions increased with increasing concentrations of Eu and Ho. Acetic acid extracted higher amounts of REE, but Eu recovery was superior to Ho. Lepidocrocite was formed as Eu concentration increased which decreased its stability in the precipitates.

  20. Acoustic testing of high temperature panels

    NASA Technical Reports Server (NTRS)

    Leatherwood, Jack D.; Clevenson, Sherman A.; Powell, Clemans A.; Daniels, Edward F.

    1990-01-01

    Results are presented of a series of thermal-acoustic tests conducted on the NASA Langley Research Center Thermal-Acoustic Test Apparatus to (1) investigate techniques for obtaining strain measurements on metallic and carbon-carbon materials at elevated temperature; (2) document the dynamic strain response characteristics of several superalloy honeycomb thermal protection system panels at elevated temperatures of up to 1200 F; and (3) determine the strain response and sonic fatigue behavior of four carbon-carbon panels at both ambient and elevated temperatures. A second study tested four carbon-carbon panels to document panel dynamic response characteristics at ambient and elevated temperature, determine time to failure and faliure modes, and collect continuous strain data up to panel failure. Strain data are presented from both types of panels, and problems encountered in obtaining reliable strain data on the carbon-carbon panels are described. The failure modes of the carbon-carbon panels are examined.

  1. HoBi-like viruses – the typical 'atypical bovine pestivirus'

    USDA-ARS?s Scientific Manuscript database

    HoBi-like viruses, also referred to as bovine viral diarrhea virus 3 (BVDV-3) and atypical pestivirus, have been proposed as a new putative bovine pestivirus species. These viruses were first identified in the last decade and are currently distributed in at least three continents. Published findings...

  2. Panel to review EOSDIS plans

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Formed in Jan. 1992, the Panel to Review EOSDIS Plans was charged with advising NASA on its plans for developing the Earth Observing System (EOS) Data and Information System (EOSDIS). Specifically, the panel was asked to do the following: assess the validity of the engineering and technical underpinnings of the EOSDIS; assess its potential value to scientific users; suggest how technical risk can be minimized; and assess whether current plans are sufficiently resilient to be adaptable to changing technology and requirements such as budget environments, data volumes, new users, and new databases. The panel completed an interim report (Addendum A) and transmitted it to NASA and other interested parties in the government on 9 Apr. 1992. Because of a delay in NASA's plans to select the contractor for EOSDIS, the panel was not able to complete its review of the program according to the original government request. With the issuance of a letter report (Addendum B) on 28 Sep. 1992, the panel became inactive until such time as NASA could release the details of the contractor's proposed architecture, schedule, and costs for developing EOSDIS. In early 1993, NASA awarded the contract for the EOSDIS Core System (ECS). On 20 Apr. 1993, NASA asked the panel to reconvene to do the following: ( 1) complete its review of NASA's approach to the EOSDIS architecture and implementation; (2) appraise NASA's responses to the panel's previous recommendations; and (3) review the planning for EOSDIS in the context of NASA's role in the Global Change Data and Information System (GCDIS) implementation plan. To respond to the NASA charge, the panel met three times in 1993 including sessions with NASA officials and the EOSDIS contractor. In addition, several of the panel members visited individual Distributed Active Archive Centers (DAAC's) to obtain additional views of EOSDIS. The panel has now obtained substantial information on the EOSDIS budget, contractor work program, and current

  3. Highly stretchable, transparent ionic touch panel

    NASA Astrophysics Data System (ADS)

    Kim, Chong-Chan; Lee, Hyun-Hee; Oh, Kyu Hwan; Sun, Jeong-Yun

    2016-08-01

    Because human-computer interactions are increasingly important, touch panels may require stretchability and biocompatibility in order to allow integration with the human body. However, most touch panels have been developed based on stiff and brittle electrodes. We demonstrate an ionic touch panel based on a polyacrylamide hydrogel containing lithium chloride salts. The panel is soft and stretchable, so it can sustain a large deformation. The panel can freely transmit light information because the hydrogel is transparent, with 98% transmittance for visible light. A surface-capacitive touch system was adopted to sense a touched position. The panel can be operated under more than 1000% areal strain without sacrificing its functionalities. Epidermal touch panel use on skin was demonstrated by writing words, playing a piano, and playing games.

  4. MTR WING, TRA604. PRECAST CONCRETE PANELS AND DIMENSIONS FOR PANELS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR WING, TRA-604. PRECAST CONCRETE PANELS AND DIMENSIONS FOR PANELS K THROUGH Q. BLAW-KNOX 3150-804-21, SHEET #2, 11/1950. INL INDEX NO. 531-0604-62-098-100645, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  5. Aerospace safety advisory panel

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report from the Aerospace Safety Advisory Panel (ASAP) contains findings, recommendations, and supporting material concerning safety issues with the space station program, the space shuttle program, aeronautics research, and other NASA programs. Section two presents findings and recommendations, section three presents supporting information, and appendices contain data about the panel membership, the NASA response to the March 1993 ASAP report, and a chronology of the panel's activities during the past year.

  6. A general panel sizing computer code and its application to composite structural panels

    NASA Technical Reports Server (NTRS)

    Anderson, M. S.; Stroud, W. J.

    1978-01-01

    A computer code for obtaining the dimensions of optimum (least mass) stiffened composite structural panels is described. The procedure, which is based on nonlinear mathematical programming and a rigorous buckling analysis, is applicable to general cross sections under general loading conditions causing buckling. A simplified method of accounting for bow-type imperfections is also included. Design studies in the form of structural efficiency charts for axial compression loading are made with the code for blade and hat stiffened panels. The effects on panel mass of imperfections, material strength limitations, and panel stiffness requirements are also examined. Comparisons with previously published experimental data show that accounting for imperfections improves correlation between theory and experiment.

  7. Ho3+-doped strontium-aluminium-bismuth-borate glasses for green light emission.

    PubMed

    Rajesh, D; Dhamodhara Naidu, M; Ratnakaram, Y C; Balakrishna, A

    2014-11-01

    Strontium-aluminium-bismuth-borate glasses (SAlBiB) doped with different concentrations of Ho(3+) were prepared using conventional melt quenching technique and their structural and optical properties investigated. X-ray diffraction and scanning electron microscopy analysis were used to study the structural properties. Optical properties were studied by measuring the optical absorption and visible luminescence spectra. The Judd-Ofelt (J-O) theory was applied to evaluate J-O intensity parameters, Ω(λ) (λ = 2, 4 and 6). Using J-O intensity parameters, radiative properties such as spontaneous transition probabilities (A(R)), branching ratios (β(R)) and radiative lifetimes (τ(R)) were determined. From the emission spectra, a strong green emission nearly at 549 nm corresponding to the transition, (5)S2 ((5)F4)→(5)I(8) was observed. Emission peak positions (λ(P)), effective bandwidths (Δλ(eff)) and stimulated emission cross-sections (σ(p)) were calculated for the observed emission transitions, (5)F3 →(5)I(8), (5)S2((5)F4)→(5)I(8) and (5)F5 →(5)I(8) of Ho(3+) in all the glass matrices. Chromaticity color coordinates were calculated using the emission spectra. The experimental results suggest that SAlBiB glass matrix with 1.5 mol% of Ho(3+) has better emission properties. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Butein induction of HO-1 by p38 MAPK/Nrf2 pathway in adipocytes attenuates high-fat diet induced adipose hypertrophy in mice.

    PubMed

    Wang, Zheng; Ka, Sun-O; Lee, Youngyi; Park, Byung-Hyun; Bae, Eun Ju

    2017-03-15

    Adipose tissue inflammation and oxidative stress are key components in the development of obesity and insulin resistance. Heme oxygenase (HO)-1 in adipocytes protects against obesity and adipose dysfunction. In this study, we report the identification of butein, a flavonoid chalcone, as a novel inducer of HO-1 expression in adipocytes in vitro and in vivo. Butein upregulated HO-1 mRNA and protein expression in 3T3-L1 adipocytes, accompanied by Kelch-Like ECH-Associated Protein (Keap) 1 degradation and increase in the nuclear level of nuclear factor erythroid 2-related factor 2 (Nrf2). Butein modulation of Keap1 and Nrf2 as well as HO-1 upregulation was reversed by pretreatment with p38 MAPK inhibitor SB203580, indicating the involvement of p38 MAPK in butein activation of Nrf2 in adipocytes. In addition, HO-1 activation by butein led to the inhibitions of reactive oxygen species and adipocyte differentiation, as evidenced by the fact that butein repression of reactive oxygen species and adipogenesis was reversed by pretreatment with HO-1 inhibitor SnPP. Induction of HO-1 expression by butein was also demonstrated in the adipose tissue of C57BL/6 mice fed a high-fat diet administered along with butein for three weeks, and correlated with the inhibitions of adiposity and adipose tissue inflammation, which were reversed by co-administration of SnPP. Altogether, our results demonstrate that butein activates the p38 MAPK/Nrf2/HO-1 pathway to act as a potent inhibitor of adipose hypertrophy and inflammation in a diet-induced obesity model and thus has potential for suppressing obesity-linked metabolic syndrome. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Lack of evidence for the presence of emerging HoBi-like viruses in North American fetal bovine serum lots.

    USDA-ARS?s Scientific Manuscript database

    The detection of HoBi-like virus in fetal bovine serum (FBS) labeled as United States of America (USA) origin, but packaged in Europe, raised concerns that HoBi-like virus may have entered the USA. In this study, 90 lots of FBS originating in North America (NA) were screened for pestivirus antigen ...

  10. Energy transfer characteristics of silicate glass doped with Er3+, Tm3+, and Ho3+ for ˜2 μm emission

    NASA Astrophysics Data System (ADS)

    Li, Ming; Liu, Xueqiang; Guo, Yanyan; Hu, Lili; Zhang, Junjie

    2013-12-01

    A Er3+/Tm3+/Ho3+ tri-doped silicate glass with good thermal stability is prepared by melt-quenching method. Efficient ˜2 μm emission is observed under 808 nm laser excitation. It is found that the 2.0 μm emission of Ho3+ can be enhanced under the excitation at 808 nm by incorporating Er3+ and Tm3+. Based on the measurement of absorption spectra, the Judd-Ofelt intensity parameters, radiation emission probability, and branching ratio are calculated to evaluate the spectroscopic properties simultaneously. The maximum value of emission cross section of Ho3+ is 3.54 × 10-21 cm2 at 2008 nm. Additionally, the phonon assistance and the micro-parameters in the energy transfer process are quantitatively analyzed by using Dexter model. The energy transfer coefficient from Tm3+ to Ho3+ can reach as high as 21.44 × 10-40 cm6/s, respectively. The emission property together with good thermal property indicates that Er3+/Tm3+/Ho3+ tri-doped silicate glass is a potential kind of laser glass for efficient 2 μm laser.

  11. The Effect of Temperature on the Radiative Performance of Ho-Yag Thin Film Selective Emitters

    NASA Technical Reports Server (NTRS)

    Lowe, Roland A.; Chubb, Donald L.; Good, Brian S.

    1995-01-01

    We present the emitter efficiency results for the thin film 25 percent Ho YAG (Yttrium Aluminum Garnet, Y3Al5O12) selective emitter from 1000 to 1700 K with a platinum substrate. Spectral emittance and emissive power measurements were made (1.2 less than lambda less than 3.2 microns) and used to calculate the radiative efficiency. The radiative efficiency and power density of rare earth doped selective emitters are strongly dependent on temperature and experimental results indicate an optimum temperature (1650 K for Ho YAG) for thermophotovoltaic (TPV) applications.

  12. Comparison of 2 micron Ho and 10 micron CO2 lidar for atmospheric backscatter and Doppler windshear detection

    NASA Technical Reports Server (NTRS)

    Killinger, Dennis

    1991-01-01

    The development of eye-safe, solid-state Lidar systems is discussed, with an emphasis on Coherent Doppler Lidar for Atmospheric Wind Measurements. The following subject areas are covered: tunable Ho DIAL (Differential Absorption Lidar)/lidar atmospheric measurements; atmospheric turbulence measurements and detector arrays; diurnal measurements of C(sub n)(sup 2) for KSC lidar measurements; and development of single-frequency Ho laser/lidar.

  13. 78 FR 41937 - Joint Meeting of the Gastroenterology-Urology Panel and the Radiological Devices Panel of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-12

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-N-0816] Joint Meeting of the Gastroenterology-Urology Panel and the Radiological Devices Panel of the Medical...: Gastroenterology-Urology Panel and Radiological Devices Panel of the Medical Devices Advisory Committee. General...

  14. Programme Note: Realities and Opportunities in Ho Chi Minh City.

    ERIC Educational Resources Information Center

    Franchet, Chi Nguyen

    1996-01-01

    The current status of street children in Ho Chi Minh City, Vietnam, is characterized by marginalization from society through street vending, begging, theft, and prostitution. Evaluation of a drop-in center serving children without family linkages indicates need for needs assessments, follow-up activities, measurement of individual child progress,…

  15. Spectroscopy and excitation dynamics of the trivalent lanthanides Tm(3+) and Ho(3+) in LiYF4

    NASA Technical Reports Server (NTRS)

    Walsh, Brian M.

    1995-01-01

    A detailed study of the spectroscopy and excitation dynamics Tm3+ and Ho3+ in yttrium lithium fluoride, LiYF4 (YLF), has been done. Absorption spectroscopy is utilized in the Judd-Ofelt theory to determine radiative transition rates of spontaneous emission. Luminescence spectroscopy is studied under cw diode laser excitation at 785nm. The effect of dopant ion concentration and excitation power on the observed luminescence are considered in these measurements. An analysis of these measurements have been used to determine channels of energy transfer between Tm3+ and Ho3+ ions. The temporal response of Tm and Ho in singly and co-doped YLF to pulsed laser excitation with a Ti:Al2O3 laser and a CoMgF2 laser turned to various wavelengths have also been studied. The energy transfer mechanisms of cross relaxation, upconversion, and resonant energy transfer between Tm3+ and Ho3+ ions have been modeled, and the model parameters extracted by a fitting procedure to the measured temporal response curves. Rate equation approaches to modeling are presented that result in predictions of rate constants for energy transfer processes, as well as more conventional approaches to modeling such as the Forster-Dexter models, which give the interaction strengths in terms of microscopic interaction parameters.

  16. N-Acetylcysteine and Allopurinol Confer Synergy in Attenuating Myocardial Ischemia Injury via Restoring HIF-1α/HO-1 Signaling in Diabetic Rats

    PubMed Central

    Mao, Xiaowen; Wang, Tingting; Liu, Yanan; Irwin, Michael G.; Ou, Jing-song; Liao, Xiao-long; Gao, Xia; Xu, Yuan; Ng, Kwok F. J.; Vanhoutte, Paul M.; Xia, Zhengyuan

    2013-01-01

    Objectives To determine whether or not the antioxidants N-acetylcysteine (NAC) and allopurinol (ALP) confer synergistic cardioprotection against myocardial ischemia/reperfusion (MI/R) injury by stabilizing hypoxia inducible factor 1α (HIF-1α)/heme oxygenase 1 (HO-1) signaling in diabetic myocardium. Methods Control or diabetic [streptozotocin (STZ)-induced] Sprague Dawley rats received vehicle or NAC, ALP or their combination for four weeks starting one week after STZ injection. The animals were then subjected to thirty minutes of coronary artery occlusion followed by two hours reperfusion in the absence or presence of the selective HO-1 inhibitor, tin protoporphyrin-IX (SnPP-IX) or the HIF-1α inhibitor 2-Methoxyestradiol (2ME2). Cardiomyocytes exposed to high glucose were subjected to hypoxia/re-oxygenation in the presence or absence of HIF-1α and HO-1 achieved by gene knock-down with related siRNAs. Results Myocardial and plasma levels of 15-F2t-isoprostane, an index of oxidative stress, were significantly increased in diabetic rats while cardiac HO-1 protein and activity were reduced; this was accompanied with reduced cardiac protein levels of HIF-1α, and increased post-ischemic myocardial infarct size and cellular injury. NAC and ALP given alone and in particular their combination normalized cardiac levels of HO-1 and HIF-1α protein expression and prevented the increase in 15-F2t-isoprostane, resulting in significantly attenuated post-ischemic myocardial infarction. NAC and ALP also attenuated high glucose-induced post-hypoxic cardiomyocyte death in vitro. However, all the above protective effects of NAC and ALP were cancelled either by inhibition of HO-1 or HIF-1α with SnPP-IX and 2ME2 in vivo or by HO-1 or HIF-1α gene knock-down in vitro. Conclusion NAC and ALP confer synergistic cardioprotection in diabetes via restoration of cardiac HIF-1α and HO-1 signaling. PMID:23874823

  17. Glutaredoxin 1 (GRX1) inhibits oxidative stress and apoptosis of chondrocytes by regulating CREB/HO-1 in osteoarthritis.

    PubMed

    Sun, Jie; Wei, Xuelei; Lu, Yandong; Cui, Meng; Li, Fangguo; Lu, Jie; Liu, Yunjiao; Zhang, Xi

    2017-10-01

    GRX1 (glutaredoxin1), a sulfhydryl disulfide oxidoreductase, is involved in many cellular processes, including anti-oxidation, anti-apoptosis, and regulation of cell differentiation. However, the role of GRX1 in the oxidative stress and apoptosis of osteoarthritis chondrocytes remains unclear, prompting the current study. Protein and mRNA expressions were measured by Western blot and RT-qPCR. Oxidative stress was detected by the measurement of MDA and SOD contents. Cells apoptosis were detected by Annexin V-FITC/PI and caspase-3 activity assays. We found that the mRNA and protein expressions of GRX1 were significantly down-regulated in osteoarthritis tissues and cells. GRX1 overexpression increased the mRNA and protein expression of CREB and HO-1. Meanwhile, GRX1 overexpression inhibited oxidative stress and apoptosis in osteoarthritis chondrocytes. Furthermore, we found that GRX1 overexpression regulated HO-1 by increasing CREB, and that HO-1 regulated oxidative stress and apoptosis in osteoarthritis chondrocytes. Thus, GRX1 overexpression constrains oxidative stress and apoptosis in osteoarthritis chondrocytes by regulating CREB/HO-1, providing a novel insight into the molecular mechanism and potential treatment of osteoarthritis. Copyright © 2017. Published by Elsevier Ltd.

  18. Role of Nrf2/HO-1 system in development, oxidative stress response and diseases: an evolutionarily conserved mechanism.

    PubMed

    Loboda, Agnieszka; Damulewicz, Milena; Pyza, Elzbieta; Jozkowicz, Alicja; Dulak, Jozef

    2016-09-01

    The multifunctional regulator nuclear factor erythroid 2-related factor (Nrf2) is considered not only as a cytoprotective factor regulating the expression of genes coding for anti-oxidant, anti-inflammatory and detoxifying proteins, but it is also a powerful modulator of species longevity. The vertebrate Nrf2 belongs to Cap 'n' Collar (Cnc) bZIP family of transcription factors and shares a high homology with SKN-1 from Caenorhabditis elegans or CncC found in Drosophila melanogaster. The major characteristics of Nrf2 are to some extent mimicked by Nrf2-dependent genes and their proteins including heme oxygenase-1 (HO-1), which besides removing toxic heme, produces biliverdin, iron ions and carbon monoxide. HO-1 and their products exert beneficial effects through the protection against oxidative injury, regulation of apoptosis, modulation of inflammation as well as contribution to angiogenesis. On the other hand, the disturbances in the proper HO-1 level are associated with the pathogenesis of some age-dependent disorders, including neurodegeneration, cancer or macular degeneration. This review summarizes our knowledge about Nrf2 and HO-1 across different phyla suggesting their conservative role as stress-protective and anti-aging factors.

  19. HO-1 gene overexpression enhances the beneficial effects of superparamagnetic iron oxide labeled bone marrow stromal cells transplantation in swine hearts underwent ischemia/reperfusion: an MRI study.

    PubMed

    Jiang, Yibo; Chen, Lijuan; Tang, Yaoliang; Ma, Genshan; Shen, Chengxing; Qi, Chunmei; Zhu, Qi; Yao, Yuyu; Liu, Naifeng

    2010-05-01

    To determine the effect of intracoronary transfer of superparamagnetic iron oxide (SPIO) labeled heme oxygenase-1 (HO-1) overexpressed bone marrow stromal cells (BMSCs) in a porcine myocardial ischemia/reperfusion model. Cell apoptosis was assayed and supernatant cytokine concentrations were measured in BMSCs that underwent hypoxia/reoxygen in vitro. Female mini-swines that underwent 1 h LAD occlusion followed by 1 h reperfusion were randomly allocated to receive intracoronary saline (control), 1 x 10(7) SPIO-labeled BMSCs transfected with pcDNA3.1-Lacz plasmid (Lacz-BMSCs), pcDNA3.1-human HO-1 (HO-1-BMSCs), pcDNA3.1-hHO-1 pretreated with a HO inhibitor, tin protoporphyrin (SnPP, n = 10 each). MRI and postmortem histological analysis were made at 1 week or 3 months thereafter. Post hypoxia/reoxygen in vitro, apoptosis was significantly reduced, supernatant VEGF significantly increased while TNF-alpha and IL-6 significantly reduced in HO-1-BMSCs group compared with Lacz-BMSCs group (all p < 0.05). Myocardial expression of VEGF was significantly higher in HO-1-BMSCs than in Lacz-BMSCs group at 1 week post transplantation (all p < 0.05). Signal voids induced by the SPIO were detected in the peri-infarction region in all BMSC groups at 1 week but not at 3 months post transplantation and the extent of the hypointense signal was the highest in HO-1-BMSCs group, and histological analysis showed that signal voids represented cardiac macrophages that engulfed the SPIO-labeled BMSCs. Pretreatment with SnPP significantly attenuated the beneficial effects of HO-1-BMSCs. Transplantation of HO-1-overexpressed BMSCs significantly enhanced the beneficial effects of BMSCs on improving cardiac function in this model.

  20. Imi Ho'ola post-baccalaureate program: recruitment, retention, and graduation of Asian American and Pacific Islander students in medicine.

    PubMed

    Judd, N L; Sing, P M

    2001-09-01

    Imi Ho'ola has been a successful model for training underrepresented minorities and disadvantaged individuals in medicine at the University of Hawai'i. This program has 28 years of experience assisting students to prepare for, qualify for, and complete the M.D. program, thereby producing medical doctors and other health professionals for Hawai'i, Guam, American Samoa, the U.S. Associated Pacific Islands (USAPI), and the continental U.S. Recently, Imi Ho'ola has expanded its outreach efforts to create an educational pathway for local high school and college students encouraging them to pursue higher education and health careers. A description of the Imi Ho'ola is presented with emphasis on its post-baccalaureate curriculum begun in 1995.

  1. (⁹⁹m)Tc-MAA overestimates the absorbed dose to the lungs in radioembolization: a quantitative evaluation in patients treated with ¹⁶⁶Ho-microspheres.

    PubMed

    Elschot, Mattijs; Nijsen, Johannes F W; Lam, Marnix G E H; Smits, Maarten L J; Prince, Jip F; Viergever, Max A; van den Bosch, Maurice A A J; Zonnenberg, Bernard A; de Jong, Hugo W A M

    2014-10-01

    Radiation pneumonitis is a rare but serious complication of radioembolic therapy of liver tumours. Estimation of the mean absorbed dose to the lungs based on pretreatment diagnostic (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) imaging should prevent this, with administered activities adjusted accordingly. The accuracy of (99m)Tc-MAA-based lung absorbed dose estimates was evaluated and compared to absorbed dose estimates based on pretreatment diagnostic (166)Ho-microsphere imaging and to the actual lung absorbed doses after (166)Ho radioembolization. This prospective clinical study included 14 patients with chemorefractory, unresectable liver metastases treated with (166)Ho radioembolization. (99m)Tc-MAA-based and (166)Ho-microsphere-based estimation of lung absorbed doses was performed on pretreatment diagnostic planar scintigraphic and SPECT/CT images. The clinical analysis was preceded by an anthropomorphic torso phantom study with simulated lung shunt fractions of 0 to 30 % to determine the accuracy of the image-based lung absorbed dose estimates after (166)Ho radioembolization. In the phantom study, (166)Ho SPECT/CT-based lung absorbed dose estimates were more accurate (absolute error range 0.1 to -4.4 Gy) than (166)Ho planar scintigraphy-based lung absorbed dose estimates (absolute error range 9.5 to 12.1 Gy). Clinically, the actual median lung absorbed dose was 0.02 Gy (range 0.0 to 0.7 Gy) based on posttreatment (166)Ho-microsphere SPECT/CT imaging. Lung absorbed doses estimated on the basis of pretreatment diagnostic (166)Ho-microsphere SPECT/CT imaging (median 0.02 Gy, range 0.0 to 0.4 Gy) were significantly better predictors of the actual lung absorbed doses than doses estimated on the basis of (166)Ho-microsphere planar scintigraphy (median 10.4 Gy, range 4.0 to 17.3 Gy; p < 0.001), (99m)Tc-MAA SPECT/CT imaging (median 2.5 Gy, range 1.2 to 12.3 Gy; p < 0.001), and (99m)Tc-MAA planar scintigraphy (median 5.5 Gy, range 2.3 to 18.2 Gy; p < 0

  2. Energy transfer and 2.0 μm emission in Tm{sup 3+}/Ho{sup 3+} co-doped α-NaYF{sub 4} single crystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feng, Zhigang; Yang, Shuo; Xia, Haiping, E-mail: hpxcm@nbu.edu.cn

    2016-04-15

    Highlights: • Cubic NaYF{sub 4} single crystals co-doped with ∼1.90 mol% Tm{sup 3+} and various Ho{sup 3+} concentrations were grown by Bridgman method. • The maximum fluorescence lifetime was 23.23 ms for Tm{sup 3+} (1.90 mol%)/Ho{sup 3+} (3.89 mol%) co-doped α-NaYF{sub 4}. • The obtained energy transfer rate (W{sub ET}) and energy transfer efficiency (η) of Tm{sup 3+}:{sup 3}F{sub 4} are 1077 s{sup −1} and 95.0%, respectively. • The maximum emission cross section reached 1.06 × 10{sup −20} cm{sup 2}. - Abstract: Cubic NaYF{sub 4} single crystals co-doped with ∼1.90 mol% Tm{sup 3+} and various Ho{sup 3+} concentrations were grownmore » by Bridgman method. The energy transfer from Tm{sup 3+} to Ho{sup 3+} and the optimum fluorescence emission around 2.04 μm of Ho{sup 3+} ion were investigated based on the measured absorption spectra, emission spectra, emission cross section and decay curves under excitation of 800 nm LD. The emission intensity at 2.04 μm increased with the increase of Ho{sup 3+} concentration from 0.96 mol% to 3.89 mol% when the concentration of Tm{sup 3+} was held constantly at ∼1.90 mol%. Moreover, the maximum emission cross section reached 1.06 × 10{sup −20} cm{sup 2} and the maximum fluorescence lifetime was 23.23 ms for Tm{sup 3+}(1.90 mol%)/Ho{sup 3+}(3.89 mol%) co-doped one. According to the measured lifetime of Tm{sup 3+} single-doped and Tm{sup 3+}/Ho{sup 3+} co-doped samples, the maximum energy transfer efficiency of Tm{sup 3+}:{sup 3}F{sub 4} level was 95.0%. Analysis on the fluorescence dynamics indicated that electric dipole–dipole is dominant for the energy transfer from Tm{sup 3+} to Ho{sup 3+}.« less

  3. Fructose Mediated Non-Alcoholic Fatty Liver Is Attenuated by HO-1-SIRT1 Module in Murine Hepatocytes and Mice Fed a High Fructose Diet

    PubMed Central

    Sodhi, Komal; Puri, Nitin; Favero, Gaia; Stevens, Sarah; Meadows, Charles; Abraham, Nader G.; Rezzani, Rita; Ansinelli, Hayden; Lebovics, Edward; Shapiro, Joseph I.

    2015-01-01

    Background Oxidative stress underlies the etiopathogenesis of nonalcoholic fatty liver disease (NAFLD), obesity and cardiovascular disease (CVD). Heme Oxygenase-1 (HO-1) is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. Sirtuin1 (SIRT1) belongs to the family of NAD-dependent de-acyetylases and is modulated by cellular redox. Hypothesis We hypothesize that fructose-induced obesity creates an inflammatory and oxidative environment conducive to the development of NAFLD and metabolic syndrome. The aim of this study is to determine whether HO-1 acts through SIRT1 to form a functional module within hepatocytes to attenuate steatohepatitis, hepatic fibrosis and cardiovascular dysfunction. Methods and Results We examined the effect of fructose, on hepatocyte lipid accumulation and fibrosis in murine hepatocytes and in mice fed a high fructose diet in the presence and absence of CoPP, an inducer of HO-1, and SnMP, an inhibitor of HO activity. Fructose increased oxidative stress markers and decreased HO-1 and SIRT1 levels in hepatocytes (p<0.05). Further fructose supplementation increased FAS, PPARα, pAMPK and triglycerides levels; CoPP negated this increase. Concurrent treatment with CoPP and SIRT1 siRNA in hepatocytes increased FAS, PPARα, pAMPK and triglycerides levels suggesting that HO-1 is upstream of SIRT1 and suppression of SIRT1 attenuates the beneficial effects of HO-1. A high fructose diet increased insulin resistance, blood pressure, markers of oxidative stress and lipogenesis along with fibrotic markers in mice (p<0.05). Increased levels of HO-1 increased SIRT1 levels and ameliorated fructose-mediated lipid accumulation and fibrosis in liver along with decreasing vascular dysfunction (p<0.05 vs. fructose). These beneficial effects of CoPP were reversed by SnMP. Conclusion Taken together, our study demonstrates, for the first time, that HO-1 induction attenuates fructose-induced hepatic lipid deposition, prevents the

  4. Use of Internet panels to conduct surveys.

    PubMed

    Hays, Ron D; Liu, Honghu; Kapteyn, Arie

    2015-09-01

    The use of Internet panels to collect survey data is increasing because it is cost-effective, enables access to large and diverse samples quickly, takes less time than traditional methods to obtain data for analysis, and the standardization of the data collection process makes studies easy to replicate. A variety of probability-based panels have been created, including Telepanel/CentERpanel, Knowledge Networks (now GFK KnowledgePanel), the American Life Panel, the Longitudinal Internet Studies for the Social Sciences panel, and the Understanding America Study panel. Despite the advantage of having a known denominator (sampling frame), the probability-based Internet panels often have low recruitment participation rates, and some have argued that there is little practical difference between opting out of a probability sample and opting into a nonprobability (convenience) Internet panel. This article provides an overview of both probability-based and convenience panels, discussing potential benefits and cautions for each method, and summarizing the approaches used to weight panel respondents in order to better represent the underlying population. Challenges of using Internet panel data are discussed, including false answers, careless responses, giving the same answer repeatedly, getting multiple surveys from the same respondent, and panelists being members of multiple panels. More is to be learned about Internet panels generally and about Web-based data collection, as well as how to evaluate data collected using mobile devices and social-media platforms.

  5. Building with stress-skin panels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bliss, S.

    1983-10-01

    A promising new technique for constructing homes that employs stress-skin panels is described. In this method, the insulation, drywall, and sheathing are hung in a single panel. The panels are made in 4 x 8 ft. and up and are either laminated or foamed in place. Both processes require strict manufacturing controls.

  6. Investigation of panel-to-panel connections and block-outs for full-depth precast concrete bridge decks.

    DOT National Transportation Integrated Search

    2015-06-01

    Experimental tests were performed at Virginia Tech to investigate transverse panel-to-panel connections and horizontal shear : connector block-outs for full-depth precast concrete bridge deck panels. The connections were designed for a deck replaceme...

  7. Pop-Art Panels

    ERIC Educational Resources Information Center

    Alford, Joanna

    2012-01-01

    James Rosenquist's giant Pop-art panels included realistic renderings of well-known contemporary foods and objects, juxtaposed with famous people in the news--largely from the 1960s, '70s and '80s--and really serve as visual time capsules. In this article, eighth-graders focus on the style of James Rosenquist to create their own Pop-art panel that…

  8. Panelized wall system with foam core insulation

    DOEpatents

    Kosny, Jan [Oak Ridge, TN; Gaskin, Sally [Houston, TX

    2009-10-20

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  9. Testing fast photochemical theory during TRACE-P based on measurements of OH, HO2, and CH2O

    NASA Astrophysics Data System (ADS)

    Olson, Jennifer R.; Crawford, J. H.; Chen, G.; Fried, A.; Evans, M. J.; Jordan, C. E.; Sandholm, S. T.; Davis, D. D.; Anderson, B. E.; Avery, M. A.; Barrick, J. D.; Blake, D. R.; Brune, W. H.; Eisele, F. L.; Flocke, F.; Harder, H.; Jacob, D. J.; Kondo, Y.; Lefer, B. L.; Martinez, M.; Mauldin, R. L.; Sachse, G. W.; Shetter, R. E.; Singh, H. B.; Talbot, R. W.; Tan, D.

    2004-08-01

    Measurements of several short-lived photochemical species (e.g., OH, HO2, and CH2O) were obtained from the DC-8 and P3-B aircraft during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) campaign. To assess fast photochemical theory over the east Asian coast and western Pacific, these measurements are compared to predictions using a photochemical time-dependent box model constrained by coincident measurements of long-lived tracers and physical parameters. Both OH and HO2 are generally overpredicted by the model throughout the troposphere, which is a different result from previous field campaigns. The calculated-to-observed ratio of OH shows an altitude trend, with OH overpredicted by 80% in the upper troposphere and by 40-60% in the middle troposphere. Boundary layer and lower tropospheric OH ratios decrease from middle tropospheric values to 1.07 for the DC-8 and to 0.70 for the P3-B. HO2 measured on the DC-8 is overpredicted by a median of 23% and shows no trend in the agreement with altitude. Three subsets of data which compose 12% of the HO2 measurements represent outliers with respect to calculated-to-observed ratios: stratospherically influenced air, upper tropospheric data with NO > 135 pptv, and data from within clouds. Pronounced underpredictions of both HO2 and OH were found for stratospherically influenced air, which is in contrast to previous studies showing good agreement of predicted and observed HOx in the stratosphere. Observational evidence of heterogeneous uptake of HO2 within low and middle tropospheric clouds is presented, though there is no indication of significant HO2 uptake within higher-altitude clouds. Model predictions of CH2O are in good agreement with observations in the median for background concentrations, but a large scatter exists. Factors contributing to this scatter are examined, including the limited availability of some important constraining measurements, particularly CH3OOH. Some high concentrations of CH2O

  10. Close up view of switchboard panel operator's station #1; panel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close up view of switchboard panel operator's station #1; panel contains 1200 push-pull button switches which control poer to red, green, and white indicating lights on the model board; white lights indicate that power is off; green lights indicate that equipment (switch breaker or transformer) is off; red lights indicate that equipment is on - Thirtieth Street Station, Power Director Center, Thirtieth & Market Streets in Amtrak Railroad Station, Philadelphia, Philadelphia County, PA

  11. Panel methods: An introduction

    NASA Technical Reports Server (NTRS)

    Erickson, Larry L.

    1990-01-01

    Panel methods are numerical schemes for solving (the Prandtl-Glauert equation) for linear, inviscid, irrotational flow about aircraft flying at subsonic or supersonic speeds. The tools at the panel-method user's disposal are (1) surface panels of source-doublet-vorticity distributions that can represent nearly arbitrary geometry, and (2) extremely versatile boundary condition capabilities that can frequently be used for creative modeling. Panel-method capabilities and limitations, basic concepts common to all panel-method codes, different choices that were made in the implementation of these concepts into working computer programs, and various modeling techniques involving boundary conditions, jump properties, and trailing wakes are discussed. An approach for extending the method to nonlinear transonic flow is also presented. Three appendices supplement the main test. In appendix 1, additional detail is provided on how the basic concepts are implemented into a specific computer program (PANAIR). In appendix 2, it is shown how to evaluate analytically the fundamental surface integral that arises in the expressions for influence-coefficients, and evaluate its jump property. In appendix 3, a simple example is used to illustrate the so-called finite part of the improper integrals.

  12. Demonstration of Temperature Dependent Energy Migration in Dual-Mode YVO4: Ho3+/Yb3+ Nanocrystals for Low Temperature Thermometry

    PubMed Central

    Kumar Mahata, Manoj; Koppe, Tristan; Kumar, Kaushal; Hofsäss, Hans; Vetter, Ulrich

    2016-01-01

    A dual mode rare-earth based vanadate material (YVO4: Ho3+/Yb3+), prepared through ethylene glycol assisted hydrothermal method, demonstrating both downconversion and upconversion, along with systematic investigation of the luminescence spectroscopy within 12–300 K is presented herein. The energy transfer processes have been explored via steady-state and time-resolved spectroscopic measurements and explained in terms of rate equation description and temporal evolution below room temperature. The maximum time for energy migration from host to rare earth (Ho3+) increases (0.157 μs to 0.514 μs) with the material’s temperature decreasing from 300 K to 12 K. The mechanism responsible for variation of the transients’ character is discussed through thermalization and non-radiative transitions in the system. More significantly, the temperature of the nanocrystals was determined using not only the thermally equilibrated radiative intra-4f transitions of Ho3+ but also the decay time and rise time of vanadate and Ho3+ energy levels. Our studies show that the material is highly suitable for temperature sensing below room temperature. The maximum relative sensor sensitivity using the rise time of Ho3+ energy level (5F4/5S2) is 1.35% K−1, which is the highest among the known sensitivities for luminescence based thermal probes. PMID:27805060

  13. Mechanism of phytoestrogen puerarin-mediated cytoprotection following oxidative injury: Estrogen receptor-dependent up-regulation of PI3K/Akt and HO-1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hwang, Yong Pil; Jeong, Hye Gwang

    2008-12-15

    Phytoestrogens are polyphenolic non-steroidal plant compounds with estrogen-like biological activity. The phytoestrogen puerarin, the main isoflavone glycoside found in the root of Pueraria lobata, has been used for various medicinal purposes in traditional Chinese medicines for thousands of years. Recent studies have indicated that the estrogen receptor (ER), through interaction with p85, regulates phosphoinositide 3-kinase (PI3K) activity, revealing a physiologic, non-nuclear function of ER that may be relevant in cytoprotection. In this study, we demonstrate that the phytoestrogen puerarin inhibits tert-butyl hydroperoxide (t-BHP)-induced oxidative injury via an ER-dependent G{beta}1/PI3K/Akt and heme oxygenase-1 (HO-1) pathway. Pretreatment of Hepa1c1c7 and HepG2 cellsmore » with puerarin significantly reduced t-BHP-induced caspase-3 activation and subsequent cell death. Also, puerarin up-regulated HO-1 expression and this expression conferred cytoprotection against oxidative injury induced by t-BHP. Moreover, puerarin induced Nrf2 nuclear translocation, which is upstream of puerarin-induced HO-1 expression, and PI3K activation, a pathway that is involved in induced Nrf2 nuclear translocation, HO-1 expression and cytoprotection. Puerarin-induced up-regulation of HO-1 and cytoprotection against t-BHP were abolished by silencing Nrf2 expression with specific siRNA. Also, puerarin-mediated increases in PI3K activation and HO-1 induction were reversed by co-treatment with ICI 182,780 and pertussis toxin. Taken together, these results suggest that puerarin augments cellular antioxidant defense capacity through ER-dependent HO-1 induction via the G{beta}1/PI3K/Akt-Nrf2 signaling pathway, thereby protecting cells from oxidative stress.« less

  14. Solar panel truss mounting systems and methods

    DOEpatents

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2015-10-20

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  15. Solar panel truss mounting systems and methods

    DOEpatents

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2016-06-28

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  16. Solar panel truss mounting systems and methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the basemore » rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.« less

  17. Temporary bridge deck panels.

    DOT National Transportation Integrated Search

    2009-03-01

    The research described here has resulted in the development of a simplistic and innovative interlocking : glulam bridge deck panel for use in temporary bridge deck applications. The key feature of this panel : system is the interlocking tongue and gr...

  18. A comparison of the effects of Nd:YAG and Ho:YAG laser irradiation on dentine and enamel.

    PubMed

    Cernavin, I

    1995-04-01

    This preliminary study was undertaken to investigate the effects of Nd:YAG and Ho:YAG lasers on enamel and dentine of extracted teeth. The Ho:YAG laser (spot size 250 microns, energy density 4160 J/cm2) produced a cleaner puncture in dentine with less melting of the surrounding tissue than did the Nd:YAG laser (spot size 20 microns), energy density 50,000 J/cm2), which produced considerable melting and recrystallization of dentine and was more difficult to control. It was possible to cut enamel and dentine with both lasers, but considerable melted and recrystallized enamel was produced. From the limited observations of this study it appears that the Ho:YAG laser is more suitable for cutting both enamel and dentine than the Nd:YAG laser. More work needs to be done to ascertain the effect on enamel and dentine of modification of the parameters of both lasers.

  19. Constraints on Ho from Time-Delay Measurements of PG1115+080

    NASA Technical Reports Server (NTRS)

    Chartas, George

    2003-01-01

    The observations that were performed as part of the award titled: Constraints on Ho From Time-Delay Measurements of PG1115+080 resulted in several scientific publications and presentations. We list these publications and presentations and provide brief description of the important science presented in them.

  20. Acoustically Tailored Composite Rotorcraft Fuselage Panels

    NASA Technical Reports Server (NTRS)

    Hambric, Stephen; Shepherd, Micah; Koudela, Kevin; Wess, Denis; Snider, Royce; May, Carl; Kendrick, Phil; Lee, Edward; Cai, Liang-Wu

    2015-01-01

    A rotorcraft roof sandwich panel has been redesigned to optimize sound power transmission loss (TL) and minimize structure-borne sound for frequencies between 1 and 4 kHz where gear meshing noise from the transmission has the most impact on speech intelligibility. The roof section, framed by a grid of ribs, was originally constructed of a single honeycomb core/composite face sheet panel. The original panel has coincidence frequencies near 700 Hz, leading to poor TL across the frequency range of 1 to 4 kHz. To quiet the panel, the cross section was split into two thinner sandwich subpanels separated by an air gap. The air gap was sized to target the fundamental mass-spring-mass resonance of the double panel system to less than 500 Hz. The panels were designed to withstand structural loading from normal rotorcraft operation, as well as 'man-on-the-roof' static loads experienced during maintenance operations. Thin layers of VHB 9469 viscoelastomer from 3M were also included in the face sheet ply layups, increasing panel damping loss factors from about 0.01 to 0.05. Measurements in the NASA SALT facility show the optimized panel provides 6-11 dB of acoustic transmission loss improvement, and 6-15 dB of structure-borne sound reduction at critical rotorcraft transmission tonal frequencies. Analytic panel TL theory simulates the measured performance quite well. Detailed finite element/boundary element modeling of the baseline panel simulates TL slightly more accurately, and also simulates structure-borne sound well.

  1. Spectroscopic properties of HoAl3(BO3)4 single crystal

    NASA Astrophysics Data System (ADS)

    Ikonnikov, D. A.; Malakhovskii, A. V.; Sukhachev, A. L.; Temerov, V. L.; Krylov, A. S.; Bovina, A. F.; Aleksandrovsky, A. S.

    2014-11-01

    The Judd-Ofelt theory has been applied to analyze absorption spectra of Ho3+ ion in HoAl3(BO3)4 measured in spectral range 300-700 nm at room temperature. The Judd-Ofelt spectroscopic parameters have been determined as: Ω2 = 18.87 × 10-20 cm2, Ω4 = 17.04 × 10-20 cm2, Ω6 = 9.21 × 10-20 cm2. These parameters have been used to calculate radiative lifetimes and branching ratios of the luminescence manifolds. Three luminescent bands were found in the spectral range 450-700 nm ascribed to transitions from the 5F5, (5F4, 5S2) and 3K8 states to the ground state 5I8. Experimental intensities of these luminescence transitions were compared with those calculated by using Judd-Ofelt theory and the system of kinetic equations for populations of starting luminescing states. Probabilities of radiativeless transitions were evaluated from this comparison.

  2. Cross sections and quantum yields of the 3 micron emission for Er(3+) and Ho(3+) dopants in crystalsls

    NASA Astrophysics Data System (ADS)

    Payne, Stephen A.; Smith, Larry K.; Krupke, William F.

    1995-05-01

    The lifetime, quantum yields, and branching ratios for the 2.8 micron emissions of several Er-and Ho-doped fluorides and oxides were measured. Among the fluoride crystals examined, which included LiYF4, BaY2F8, LaF3, and KY3F10, only the Ho:LiFY4 systems showed any proof of nonradiative decay. Conversely, all the oxide crystals were affected by nonradiative processes, resulting in measured quantum yields ranging from 3.6% for Er:Y3Al5O12 to 62% for Er in Gd3Sc2Ga3O12. In addition, plots of the 2.8 micron emission cross sections for seven Er- and Ho-doped crystals were presented.

  3. Solar-Panel Dust Accumulation and Cleanings

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Air-fall dust accumulates on the solar panels of NASA's Mars Exploration Rovers, reducing the amount of sunlight reaching the solar arrays. Pre-launch models predicted steady dust accumulation. However, the rovers have been blessed with occasional wind events that clear significant amounts of dust from the solar panels.

    This graph shows the effects of those panel-cleaning events on the amount of electricity generated by Spirit's solar panels. The horizontal scale is the number of Martian days (sols) after Spirit's Jan. 4, 2005, (Universal Time) landing on Mars. The vertical scale indicates output from the rover's solar panels as a fraction of the amount produced when the clean panels first opened. Note that the gradual declines are interrupted by occasional sharp increases, such as a dust-cleaning event on sol 420.

  4. Attic Retrofits Using Nail-Base Insulated Panels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mallay, David; Kochkin, Vladimir

    This project developed and demonstrated a roof/attic energy retrofit solution using nail-base insulated panels for existing homes where traditional attic insulation approaches are not effective or feasible. Nail-base insulated panels (retrofit panels) consist of rigid foam insulation laminated to one face of a wood structural panel. The prefabricated panels are installed above the existing roof deck during a reroofing effort.

  5. Panel fabrication utilizing GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Mardesich, N.

    1984-01-01

    The development of the GaAs solar cells for space applications is described. The activities in the fabrication of GaAs solar panels are outlined. Panels were fabricated while introducing improved quality control, soldering laydown and testing procedures. These panels include LIPS II, San Marco Satellite, and a low concentration panel for Rockwells' evaluation. The panels and their present status are discussed.

  6. NREL Employee Appointed to Presidential Panel

    Science.gov Websites

    Employee Appointed to Presidential Panel For more information contact: e:mail: Public Affairs Development Panel. The panel will review current and projected U.S. energy research and development programs

  7. Insights in public health: Community strengthening through canoe culture: Ho'omana'o Mau as method and metaphor.

    PubMed

    Ho-Lastimosa, Ilima; Hwang, Phoebe W; Lastimosa, Bob

    2014-12-01

    Historical trauma occurs across generations and is evidenced by indigenous disparities. Efforts made to address this issue commonly utilize European ethnocentric methods. Rather, a community-based approach should be used to empower indigenous communities. God's Country Waimanalo (GCW) is a grassroots organization developed by Native Hawaiians for Native Hawaiians. Its wa'a (canoe) project, Ho'omana'o Mau (everlasting memories; abbreviated Ho'o) is meant to perpetuate pre-colonial Hawaiian practices by educating Native Hawaiian communities and its partners through hands on experience. Since 2012, GCW has opened its wa'a curricula to educators, counselors, and students from the University of Hawai'i at Manoa, Queen Lili'uokalani Children's Center, Alu Like, Hina Mauka, and the Youth Correctional Facility and contributed to Waimanalo based events such as funeral ash scattering and the papio fishing tournament. As metaphor, Ho'o is viewed as the catalyst to engage the next generation of Hawaiians to remember where they descend from, the lineage of chiefs and royalty, while establishing a solid foundation of independence and enhancing their ability to become self-sustaining. As a method, Ho'o is viewed as a classroom, a hands-on learning environment, and an ocean vessel, assembled according to traditional Hawaiian knowledge. Through this knowledge and practice, both indigenous and non-indigenous communities can work together in empowering Native Hawaiians to overcome historical trauma and reduce health disparities.

  8. Reaction kinetics of hydrogen atom abstraction from isopentanol by the H atom and HO2˙ radical.

    PubMed

    Parab, Prajakta Rajaram; Heufer, K Alexander; Fernandes, Ravi Xavier

    2018-04-25

    Isopentanol is a potential next-generation biofuel for future applications to Homogeneous Charge Compression Ignition (HCCI) engine concepts. To provide insights into the combustion behavior of isopentanol, especially to its auto-ignition behavior which is linked both to efficiency and pollutant formation in real combustion systems, detailed quantum chemical studies for crucial reactions are desired. H-Abstraction reaction rates from fuel molecules are key initiation steps for chain branching required for auto-ignition. In this study, rate constants are determined for the hydrogen atom abstraction reactions from isopentanol by the H atom and HO2˙ radical by implementing the CBS-QB3 composite method. For the treatment of the internal rotors, a Pitzer-Gwinn-like approximation is applied. On comparing the computed reaction energies, the highest exothermicity (ΔE = -46 kJ mol-1) is depicted for Hα abstraction by the H atom whereas the lowest endothermicity (ΔE = 29 kJ mol-1) is shown for the abstraction of Hα by the HO2˙ radical. The formation of hydrogen bonding is found to affect the kinetics of the H atom abstraction reactions by the HO2˙ radical. Further above 750 K, the calculated high pressure limit rate constants indicate that the total contribution from delta carbon sites (Cδ) is predominant for hydrogen atom abstraction by the H atom and HO2˙ radical.

  9. Mounting clips for panel installation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph

    2017-02-14

    An exemplary mounting clip for removably attaching panels to a supporting structure comprises a base, spring locking clips, a lateral flange, a lever flange, and a spring bonding pad. The spring locking clips extend upwardly from the base. The lateral flange extends upwardly from a first side of the base. The lateral flange comprises a slot having an opening configured to receive at least a portion of one of the one or more panels. The lever flange extends outwardly from the lateral flange. The spring bonding flange extends downwardly from the lever flange. At least a portion of the firstmore » spring bonding flange comprises a serrated edge for gouging at least a portion of the one or more panels when the one or more panels are attached to the mounting clip to electrically and mechanically couple the one or more panels to the mounting clip.« less

  10. A Q-switched Ho:YAG laser with double anti-misalignment corner cubes pumped by a diode-pumped Tm:YLF laser

    NASA Astrophysics Data System (ADS)

    Wang, Y. P.; Dai, T. Y.; Wu, J.; Ju, Y. L.; Yao, B. Q.

    2018-06-01

    We report the acousto-optically Q-switched Ho:YAG laser with double anti-misalignment corner cubes pumped by a diode-pumped Tm:YLF laser. In the continuous-wave operation of Ho:YAG laser, the maximum s-polarized output power of 3.2 W at 2090.3 nm was obtained under the absorbed pump power of 12.9 W by rotating the fast axis of quarter-wave plate to change the output transmission of laser cavity. The corresponding optical-to-optical conversion efficiency was 24.8% and the slope efficiency was 55.7%. When one of the corner cubes was rotated to 11.8° around vertical direction or 6.7° around horizontal direction, the laser could still operate stably. For the Q-switched operation, the pulse energy of Ho:YAG laser was 9.9 mJ with a pulse width of 53 ns at the repetition rate of 100 Hz, resulting in a peak power of 186.8 kW. The beam quality factor M2 of Ho:YAG laser was 1.3.

  11. t-BHQ Provides Protection against Lead Neurotoxicity via Nrf2/HO-1 Pathway

    PubMed Central

    Ye, Fang; Li, Xiaoyi; Li, Lili; Yuan, Jing; Chen, Jun

    2016-01-01

    The neurotoxicity of lead has been well established, and oxidative stress is strongly associated with lead-induced neurotoxicity. Nrf2 is important for protection against oxidative stress in many disease models. We applied t-BHQ, which is an Nrf2 activator, to investigate the possible role of Nrf2 in the protection against lead neurotoxicity. t-BHQ significantly attenuated the oxidative stress in developmental rats by decreasing MDA level, as well as by increasing SOD activity and GSH content, in the hippocampus and frontal cortex. Furthermore, neuronal apoptosis was detected by Nissl staining, and Bax expression was inhibited in the t-BHQ-treated group. Results showed that t-BHQ suppressed ROS production and caspase 3/7 activity but increased intracellular GSH content, in SH-SY5Y cells under lead exposure. Moreover, in vivo and in vitro, t-BHQ enhanced the nuclear translocation of Nrf2 and binding to ARE areas but did not induce Nrf2 transcription. These phenomena were confirmed using RT-PCR, EMSA, Western blot, and immunofluorescence analyses. Subsequent upregulation of the expression of HO-1, NQO1, and GCLC was observed. However, knockdown of Nrf2 or HO-1 adversely affected the protective effects of t-BHQ against lead toxicity in SH-SY5Y cells. Thus, t-BHQ can protect against lead neurotoxicity, depending on the Nrf2/HO-1 pathway. PMID:26798413

  12. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E.

    1995-01-01

    This paper describes solar cell panel designs that utilize new hgih efficiency solar cells along with lightweight rigid panel technology. The resulting designs push the W/kg and W/sq m parameters to new high levels. These new designs are well suited to meet the demand for higher performance small satellites. This paper reports on progress made on two SBIR Phase 1 contracts. One panel design involved the use of large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells of 19% efficiency combined with a lightweight rigid graphite fiber epoxy isogrid substrate configuration. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power level of 60 W/kg with a potential of reaching 80 W/kg. The second panel design involved the use of newly developed high efficiency (22%) dual junction GaInP2/GaAs/Ge solar cells combined with an advanced lightweight rigid substrate using aluminum honeycomb core with high strength graphite fiber mesh facesheets. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power of 105 W/kg and 230 W/sq m. This paper will address the construction details of the panels and an a analysis of the component weights. A strawman array design suitable for a typical small-sat mission is described for each of the two panel design technologies being studied. Benefits in respect to weight reduction, area reduction, and system cost reduction are analyzed and compared to conventional arrays.

  13. Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

    DOE PAGES

    Zhao, Z. Y.; Calder, S.; Aczel, A. A.; ...

    2016-04-25

    The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

  14. Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Z. Y.; Calder, S.; Aczel, A. A.

    The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

  15. Magnetism of Ho 1-xTb xAl₂ alloys: Critical dependence of a first-order transition on Tb concentration

    DOE PAGES

    Khan, Mahmud; Mudryk, Ya.; Gschneidner, K. A.; ...

    2011-12-27

    HoAl₂ exhibits a first-order spin reorientation transition at 20 K, which is manifested as a sharp peak in the heat capacity. When Ho is partially replaced by only 5% of Tb, the sharp heat-capacity peak in Ho 1-xTb xAl₂ (x = 0.05) disappears, and then reappears again for x ≥ 0.07. For x = 0.05, the anomaly corresponding to the spin reorientation transition is barely seen in the heat capacity, but as x exceeds 0.07 the weak anomaly transforms to a sharp peak. The spin reorientation transition temperature increases to 29 K for x = 0.05, and as x increasesmore » further the transition shifts to lower temperature and returns to ~20 K for x = 0.25. The transition is no longer observed when x exceeds 0.60. Temperature-dependent x-ray powder-diffraction data confirm the first-order nature of the spin reorientation transition for the alloy with x = 0.40, and indicate that the compound retains the room-temperature cubic structure within the sensitivity of the technique. Experimental observations are discussed considering the easy magnetization directions of HoAl₂ and TbAl₂.« less

  16. Q-switching of a Tm,Ho:KLu(WO4)2 microchip laser by a graphene-based saturable absorber

    NASA Astrophysics Data System (ADS)

    Serres, J. M.; Loiko, P.; Mateos, X.; Jambunathan, V.; Yumashev, K.; Griebner, U.; Petrov, V.; Aguiló, M.; Díaz, F.

    2016-02-01

    The first Ho microchip laser passively Q-switched using a graphene-based saturable absorber is demonstrated based on a Tm,Ho:KLu(WO4)2 crystal cut along the N g-axis. A maximum average output power of 74 mW is extracted from the diode-pumped laser at 2061 nm with a slope efficiency of 4%. Pulses as short as 200 ns with an energy of ~0.2 μJ are obtained at a repetition rate of 340 kHz. The energy transfer (ET), 3F4 (Tm3+) ↔ 5I7 (Ho3+) is studied, yielding ET parameters of P 28  =  1.69 and P 71  =  0.15  ×  10-22 cm3 μs-1, revealing the strong prevalence of direct ET.

  17. Disordered ferromagnetism in Ho2NiMnO6 double perovskite

    NASA Astrophysics Data System (ADS)

    Chakraborty, Tirthankar; Nair, Harikrishnan S.; Nhalil, Hariharan; Kumar, K. Ramesh; Strydom, André M.; Elizabeth, Suja

    2017-01-01

    Magnetic and dielectric properties of the double perovskite Ho2NiMnO6 are reported. The compound is synthesized by nitrate route and is found to crystallize in monoclinic P21/n space group. Lattice parameters obtained by refining powder x-ray diffraction data are; a  =  5.218(2) Å, b  =  5.543(2) Å, c  =  7.480(3) Å and the monoclinic angle is β ={{90.18}\\circ} (4). A phase transition is observed at {{T}\\text{C}}=86 K in the temperature-dependent magnetization curve, M(T). The inverse magnetic susceptibility, (1/χ (T) ) fits reasonably well with modified Curie-Weiss law by incorporating the paramagnetic response of Ho3+. 1/χ (T) manifests as an upward deviation from ideal Curie-Weiss behaviour well above the ferromagnetic transition. Signs of inherent Griffiths phase pertaining to the Ni/Mn subsystem are visible when one subtracts the Ho3+ paramagnetic contribution from total susceptibility and does the power-law analysis. The magnetic hysteresis at 2 K gives the maximum value of magnetization {{M}\\text{max}}≈ 15 {μ\\text{B}} /f.u. at 50 kOe. Field-derivative of magnetization at 2 K shows discontinuities which indicates the existence of metamagnetic transitions in this compound. This needs to be probed further. Out of the two dielectric relaxations observed, the one at low temperature may be attributed to phononic frequencies and that at higher temperature may be due to Maxwell-Wagner relaxation. A correlation between magnetic and lattice degrees of freedom is plausible since the anomaly in dielectric constant coincides with T C.

  18. Vibration Response Predictions for Heavy Panel Mounted Components from Panel Acreage Environment Specifications

    NASA Technical Reports Server (NTRS)

    Harrison, Phillip; Frady, Greg; Duvall, Lowery; Fulcher, Clay; LaVerde, Bruce

    2010-01-01

    The development of new launch vehicles in the Aerospace industry often relies on response measurements taken from previously developed vehicles during various stages of liftoff and ascent, and from wind tunnel models. These measurements include sound pressure levels, dynamic pressures in turbulent boundary layers and accelerations. Rigorous statistical scaling methods are applied to the data to derive new environments and estimate the performance of new skin panel structures. Scaling methods have proven to be reliable, particularly for designs similar to the vehicles used as the basis for scaling, and especially in regions of smooth acreage without exterior protuberances or heavy components mounted to the panel. To account for response attenuation of a panel-mounted component due to its apparent mass at higher frequencies, the vibroacoustics engineer often reduces the acreage vibration according to a weight ratio first suggested by Barrett. The accuracy of the reduction is reduced with increased weight of the panel-mounted component, and does not account for low-frequency amplification of the component/panel response as a system. A method is proposed that combines acreage vibration from scaling methods with finite element analysis to account for the frequency-dependent dynamics of heavy panel-mounted components. Since the acreage and mass-loaded skins respond to the same dynamic input pressure, such pressure may be eliminated in favor of a frequency-dependent scaling function applied to the acreage vibration to predict the mass-loaded panel response. The scaling function replaces the Barrett weight ratio, and contains all of the dynamic character of the loaded and unloaded skin panels. The solution simplifies for spatially uncorrelated and fully correlated input pressures. Since the prediction uses finite element models of the loaded and unloaded skins, a rich suite of response data are available to the design engineer, including interface forces, stress and strain

  19. Ductility of polystyrene waste panel

    NASA Astrophysics Data System (ADS)

    Sulistyorini, Dewi; Yasin, Iskandar

    2018-03-01

    Polystyrene waste panel is one of alternative materials that uses polystyrene waste. This experiment is to utilize the polystyrene waste as a non structural panel to be evaluated the ductility. The specimen consisted of cement 250 kg/m3, polystyrene waste was as aggregate, water cement ratio was 0.4 and wire mesh diameter was 0.6 mm with the grid 6 mm × 6 mm placed on the top and bottom of the panels. The polystyrene panels were compressed at 2 MPa. Six specimens had dimension 80 cm length, 30 cm width and the thickness planned were two varieties, they were 0.5 cm and 1 cm. Flexural testing is used to examine load and deflection to measure the ductility. The load and the deflection showed that the maximum load for the specimen with 0.5 cm thickness is 0.4, 0.56 and 0.37. And for 1 cm thickness is 0.4, 0.36, 0.64. It shows that the thickness variation does not give effect on the maximum load. Result showed the average of Displacement Ductility Index of polystyrene waste panels with 0.5 cm thickness was 1.692 and for 1 cm thickness, the average was 4.043. So the average of the panel with 0.5 cm thickness planned is under 1.99 and the panel with 1 cm thickness planned is upper 3, therefore, it is considered imperative for adequate ductility.

  20. Zinc L-carnosine suppresses inflammatory responses in lipopolysaccharide-induced RAW 264.7 murine macrophages cell line via activation of Nrf2/HO-1 signaling pathway.

    PubMed

    Ooi, Theng Choon; Chan, Kok Meng; Sharif, Razinah

    2017-10-01

    Zinc L-carnosine (ZnC) is a chelate of Zn and L-carnosine and is used clinically in the treatment of peptic ulcer. In this study, we aim to investigate the involvement of heme oxygenase-1 (HO-1) in the anti-inflammatory effects of ZnC in lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophages. We used immunoblotting analysis to evaluate the involvement of HO-1 in the anti-inflammatory effects of ZnC and the signaling pathway involved was measured using Dual luciferase reporter assay. Results from immunoblotting analysis demonstrated that pretreatment of cells with ZnC enhanced the expression of HO-1 in RAW 264.7 cells. Pretreatment of cells with HO-1 inhibitor (tin protoporphyrin IX dichloride) significantly attenuated the inhibitory effects of ZnC on nitric oxide (NO) production, inducible nitric oxide synthase (iNOS) expression and NF-κB activation in LPS-induced RAW 264.7 cells, suggesting that HO-1 play an important role in the suppression of inflammatory responses induced by ZnC. Furthermore, results from co-immunoprecipitation of Nrf2 and Keap1 and dual luciferase reporter assay showed that pretreatment of ZnC was able to activate the Nrf2 signaling pathway. Treatment of cells with p38 inhibitor (SB203580), c-Jun N-terminal kinase inhibitor (SP600125), and MEK 1/2 inhibitor (U0126) did not significantly suppress the induction of HO-1 by ZnC. Moreover, our present findings suggest that the effects of ZnC on NO production, HO-1 expression, and Nrf2 activation were attributed to its Zn subcomponent, but not l-carnosine. Pretreatment with ZnC was able to activate Nrf2/HO-1 signaling pathway, thus suppressing the expression of inflammatory mediators, such as NO and iNOS in LPS-induced RAW 264.7 cells.

  1. Advanced Solar Panel Designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E. B.

    1995-01-01

    Solar panel designs that utilize new high-efficiency solar cells and lightweight rigid panel technologies are described. The resulting designs increase the specific power (W/kg) achievable in the near-term and are well suited to meet the demands of higher performance small satellites (smallsats). Advanced solar panel designs have been developed and demonstrated on two NASA SBIR contracts at Applied Solar. The first used 19% efficient, large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells with a lightweight rigid graphite epoxy isogrid substrate configuration. A 1,445 sq cm coupon was fabricated and tested to demonstrate 60 W/kg with a high potential of achieving 80 W/kg. The second panel design used new 22% efficiency, dual-junction GaInP2/GaAs/Ge solar cells combined with a lightweight aluminum core/graphite fiber mesh facesheet substrate. A 1,445 sq cm coupon was fabricated and tested to demonstrate 105 W/kg with the potential of achieving 115 W/kg.

  2. Panel acoustic contribution analysis.

    PubMed

    Wu, Sean F; Natarajan, Logesh Kumar

    2013-02-01

    Formulations are derived to analyze the relative panel acoustic contributions of a vibrating structure. The essence of this analysis is to correlate the acoustic power flow from each panel to the radiated acoustic pressure at any field point. The acoustic power is obtained by integrating the normal component of the surface acoustic intensity, which is the product of the surface acoustic pressure and normal surface velocity reconstructed by using the Helmholtz equation least squares based nearfield acoustical holography, over each panel. The significance of this methodology is that it enables one to analyze and rank relative acoustic contributions of individual panels of a complex vibrating structure to acoustic radiation anywhere in the field based on a single set of the acoustic pressures measured in the near field. Moreover, this approach is valid for both interior and exterior regions. Examples of using this method to analyze and rank the relative acoustic contributions of a scaled vehicle cabin are demonstrated.

  3. Improved Healing after the Co-Transplantation of HO-1 and BDNF Overexpressed Mesenchymal Stem Cells in the Subacute Spinal Cord Injury of Dogs.

    PubMed

    Khan, Imdad Ullah; Yoon, Yongseok; Kim, Ahyoung; Jo, Kwang Rae; Choi, Kyeung Uk; Jung, Taeseong; Kim, Namyul; Son, YeonSung; Kim, Wan Hee; Kweon, Oh-Kyeong

    2018-01-01

    Abundant expression of proinflammatory cytokines after a spinal cord injury (SCI) creates an inhibitory microenvironment for neuroregeneration. The mesenchymal stem cells help to mitigate the inflammation and improve neural growth and survival. For this purpose, we potentiated the function of adipose-derived mesenchymal stem cells (Ad-MSCs) by transfecting them with brain-derived neurotrophic factor (BDNF) and heme oxygenase-1 (HO-1), through a lentivirus, to produce BDNF overexpressed Ad-MSCs (BDNF-MSCs), and HO-1 overexpressed Ad-MSCs (HO-1-MSCs). Sixteen SCI beagle dogs were randomly assigned into four treatment groups. We injected both HO-1 and BDNF-overexpressed MSCs as a combination group, to selectively control inflammation and induce neuroregeneration in SCI dogs, and compared this with BDNF-MSCs, HO-1-MSCs, and GFP-MSCs injected dogs. The groups were compared in terms of improvement in canine Basso, Beattie, and Bresnahan (cBBB) score during 8 weeks of experimentation. After 8 weeks, spinal cords were harvested and subjected to western blot analysis, immunofluorescent staining, and hematoxylin and eosin (H&E) staining. The combination group showed a significant improvement in hindlimb functions, with a higher BBB score, and a robust increase in neuroregeneration, depicted by a higher expression of Tuj-1, NF-M, and GAP-43 due to a decreased expression of the inflammatory markers interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), and an increased expression of interleukin-10 (IL-10) ( P ≤ 0.05). H&E staining showed more reduced intraparenchymal fibrosis in the combination group than in other groups ( P ≤ 0.05). It was thus suggested that the cotransplantation of HO-1 and BDNF-MSCs is more effective in promoting the healing of SCI. HO-1-MSCs reduce inflammation, which favors BDNF-induced neuroregeneration in SCI of dogs.

  4. HoNOSCA-D As a Measure of the Severity of Diagnosed Mental Disorders in Children and Adolescents-Psychometric Properties of the German Translation.

    PubMed

    von Wyl, Agnes; Toggweiler, Stephan; Zollinger, Ruedi

    2017-01-01

    The Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA), in use worldwide, is a 13-item measure assessing the biopsychosocial severity of mental health problems in children and adolescents. This article introduces the authorized German-language version of HoNOSCA, the HoNOSCA-D, and examines and discusses its psychometric properties based on a clinical sample of 1,533 children and adolescents aged 4;0 to 17;11 years. For the HoNOSCA-D total score (severity of mental health problems), internal consistency (Cronbach's alpha) was 0.63. The discriminative power of the items ranged from 0.07 to 0.44; the average interitem correlation was 0.11. Due to this stochastic independence, calculation of a total severity index is acceptable. Using factor analysis, the principal axis factoring and varimax rotation resulted in a four-factor structure, which with a Kaiser-Meyer-Olkin measure of sampling adequacy of 0.684 explained 30.62% of total variance. The convergent correlations with the German-language parent report version of the Strengths and Difficulties Questionnaire were as expected and showed a medium effect size. Gender and age differences in the HoNOSCA-D total score were small. Regarding the 13 items gender and age differences were negligible to medium. The highest severity was found for schizophrenia and psychotic disorders, followed by affective disorders and social behavior disorders. Overall, validity of HoNOSCA-D was clearly supported.

  5. HoNOSCA-D As a Measure of the Severity of Diagnosed Mental Disorders in Children and Adolescents—Psychometric Properties of the German Translation

    PubMed Central

    von Wyl, Agnes; Toggweiler, Stephan; Zollinger, Ruedi

    2017-01-01

    The Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA), in use worldwide, is a 13-item measure assessing the biopsychosocial severity of mental health problems in children and adolescents. This article introduces the authorized German-language version of HoNOSCA, the HoNOSCA-D, and examines and discusses its psychometric properties based on a clinical sample of 1,533 children and adolescents aged 4;0 to 17;11 years. For the HoNOSCA-D total score (severity of mental health problems), internal consistency (Cronbach’s alpha) was 0.63. The discriminative power of the items ranged from 0.07 to 0.44; the average interitem correlation was 0.11. Due to this stochastic independence, calculation of a total severity index is acceptable. Using factor analysis, the principal axis factoring and varimax rotation resulted in a four-factor structure, which with a Kaiser–Meyer–Olkin measure of sampling adequacy of 0.684 explained 30.62% of total variance. The convergent correlations with the German-language parent report version of the Strengths and Difficulties Questionnaire were as expected and showed a medium effect size. Gender and age differences in the HoNOSCA-D total score were small. Regarding the 13 items gender and age differences were negligible to medium. The highest severity was found for schizophrenia and psychotic disorders, followed by affective disorders and social behavior disorders. Overall, validity of HoNOSCA-D was clearly supported. PMID:29033858

  6. Inclusion of Population-specific Reference Panel from India to the 1000 Genomes Phase 3 Panel Improves Imputation Accuracy.

    PubMed

    Ahmad, Meraj; Sinha, Anubhav; Ghosh, Sreya; Kumar, Vikrant; Davila, Sonia; Yajnik, Chittaranjan S; Chandak, Giriraj R

    2017-07-27

    Imputation is a computational method based on the principle of haplotype sharing allowing enrichment of genome-wide association study datasets. It depends on the haplotype structure of the population and density of the genotype data. The 1000 Genomes Project led to the generation of imputation reference panels which have been used globally. However, recent studies have shown that population-specific panels provide better enrichment of genome-wide variants. We compared the imputation accuracy using 1000 Genomes phase 3 reference panel and a panel generated from genome-wide data on 407 individuals from Western India (WIP). The concordance of imputed variants was cross-checked with next-generation re-sequencing data on a subset of genomic regions. Further, using the genome-wide data from 1880 individuals, we demonstrate that WIP works better than the 1000 Genomes phase 3 panel and when merged with it, significantly improves the imputation accuracy throughout the minor allele frequency range. We also show that imputation using only South Asian component of the 1000 Genomes phase 3 panel works as good as the merged panel, making it computationally less intensive job. Thus, our study stresses that imputation accuracy using 1000 Genomes phase 3 panel can be further improved by including population-specific reference panels from South Asia.

  7. Analysis on energy transfer process of Ho3+ doped fluoroaluminate glass sensitized by Yb3+ for mid-infrared 2.85 μm emission

    NASA Astrophysics Data System (ADS)

    Zhou, Beier; Wei, Tao; Cai, Muzhi; Tian, Ying; Zhou, Jiajia; Deng, Degang; Xu, Shiqing; Zhang, Junjie

    2014-12-01

    This work reports the mid-infrared emission properties around 2.85 μm in a Yb3+/Ho3+ codoped fluoroaluminate glass. This fluoroaluminate glass shows a good thermal stability and high transmittance around 3 μm. The mid-infrared emission characteristics and energy transfer mechanism upon the excitation of the conventional 980 nm laser diode have been investigated. The prepared glass possesses higher spontaneous transition probability (31.77 s-1) along with the larger calculated emission cross section (1.91×10-20 cm2) corresponding to the laser transition of Ho3+:5I6→5I7. Besides, the upconversion, 1.2 μm and 2 μm fluorescence spectra were measured to understand mid-infrared emission behavior together with decay curves of Ho3+:5I6 level. Moreover, energy transfer microparameters between Yb3+ and Ho3+ were calculated and discussed based on Dexter's model. Hence, the advantageous spectroscopic characteristics of Yb3+/Ho3+ codoped fluoroaluminate glass as well as the good thermal property indicate that this kind of glass is an attractive host for developing mid-infrared solid state laser.

  8. Resonantly pumped high efficiency Ho:YAG laser.

    PubMed

    Shen, Ying-Jie; Yao, Bao-Quan; Duan, Xiao-Ming; Dai, Tong-Yu; Ju, You-Lun; Wang, Yue-Zhu

    2012-11-20

    High-efficient CW and Q-switched Ho:YAG lasers resonantly dual-end-pumped by two diode-pumped Tm:YLF lasers at 1908 nm were investigated. A maximum slope efficiency of 74.8% in CW operation as well as a maximum output power of 58.7 W at 83.2 W incident pump power was achieved, which corresponded to an optical-to-optical conversion efficiency of 70.6%. The maximum pulse energy of 2.94 mJ was achieved, with a 31 ns FWHM pulse width and a peak power of approximately 94.7 kW.

  9. High Efficiency End-Pumped Ho:Tm:YLF Disk Amplifier

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Singh, Upendra N.; Petros, Mulugeta; Axenson, Theresa J.; Barnes, Norman P.

    1999-01-01

    Space based coherent lidar for global wind measurement requires an all solid state laser system with high energy, high efficiency and narrow linewidth that operates in the eye safe region. A Q-switched, diode pumped Ho:Tm:YLF 2 micrometer laser with output energy of as much as 125 mJ at 6 Hz with an optical-to-optical efficiency of 3% has been reported. Single frequency operation of the laser was achieved by injection seeding. The design of this laser is being incorporated into NASA's SPARCLE (SPAce Readiness Coherent Lidar Experiment) wind lidar mission. Laser output energy ranging from 500 mJ to 2 J is required for an operational space coherent lidar. We previously developed a high energy Ho:Tm:YLF master oscillator and side pumped power amplifier system and demonstrated a 600-mJ single frequency pulse at a repetition rate of 10 Hz. Although the output energy is high, the optical-to-optical efficiency is only about 2%. Designing a high energy, highly efficient, conductively cooled 2-micrometer laser remains a challenge. In this paper, the preliminary result of an end-pumped amplifier that has a potential to provide a factor 3 of improvement in the system efficiency is reported.

  10. Is the 'Bromine Explosion' generated from the reaction BrO HO2 alone?

    NASA Astrophysics Data System (ADS)

    Behnke, Wolfgang; Zetzsch, Cornelius

    2010-05-01

    We observed bromine explosions (a fast production of atomic Br and Cl under tropospheric conditions) in various smog chamber experiments in Teflon bags at room temperature at a relative humidity of about 80% in the presence of NaCl/NaBr-aerosol, simulated sunlight and ozone (200 - 400 ppb). Time profiles of ozone and hydrocarbons (HCs: n-butane, 2,2-dimethylbutane, tetramethylbutane and toluene, initially about 2 ppb each) were monitored to determine concentrations and source strengths of OH radicals, atomic Cl and Br and the corresponding time profiles of BrCl and Br2 as their photolytic precursors. The number and size of aerosols are measured as well as their chemical composition (Br-, Cl- and oxalic acid). Full records of raw data from the smog chamber runs are available at www.eurochamp.org for potential users. Chemical box model calculations deliver concentrations of various intermediates, such as aldehydes, HO2 and RO2 radicals and the inorganic halogen compounds ClO, BrO, HOCl and HOBr, where HOBr from O3 + Br- => BrO- + O2 in the aqueous/adsorbed phase induces the following gas-phase/ heterogeneous chain reaction Br + O3 => BrO + O2(1) BrO + HO2 => HOBr + O2(2a) HOBr + (Aerosol) => HOBrad(3) Surface-adsorbed HOBr reacts with Br- or Cl- to produce Br2 or BrCl, both of which are released and photolysed. Formation of Br2 should prevail up to Cl-/Br- -ratios of about 104 (Fickert, S., J.W. Adams, J.N. Crowley, J. Geophys. Res., D104, 23719-23727, 1999). A maximum of this ratio is reached about 30 minutes after the beginning and decreases during the next hours - probably by reaction of Br2 with oxalate and absorption of HBr, formed from the reaction of Br with aldehydes. Parallel to chain reaction (1)-(3) a chain reaction replacing Br by Cl seems possible but can not be realized, since the main sink of atomic Cl is its reaction with hydrocarbons - leading to chain termination - in contrast to atomic Br (ratio of rates: kCl[O3]/kCl[HC] ~ 0.1; kBr[O3]/k

  11. Improving Strength of Postbuckled Panels Through Stitching

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.

    2007-01-01

    The behavior of blade-stiffened graphite-epoxy panels with impact damage is examined to determine the effect of adding through-the-thickness stitches in the stiffener flange-to-skin interface. The influence of stitches is evaluated by examining buckling and failure for panels with failure loads up to 3.5 times greater than buckling loads. Analytical and experimental results from four configurations of panel specimens are presented. For each configuration, two panels were manufactured with skin and flanges held together with through-the-thickness stitches introduced prior to resin infusion and curing and one panel was manufactured with no stitches holding the flange to the skin. No mechanical fasteners were used for the assembly of any of these panels. Panels with and without low-speed impact damage were loaded to failure in compression. Buckling and failure modes are discussed. Stitching had little effect on buckling loads but increased the failure loads of impact-damaged panels by up to 30%.

  12. Age-forming aluminum panels

    NASA Technical Reports Server (NTRS)

    Baxter, G. I.

    1976-01-01

    Contoured-stiffened 63 by 337 inch 2124 aluminum alloy panels are machined in-the-flat to make integral, tapered T-capped stringers, parallel with longitudinal centerline. Aging fixture, which includes net contour formers made from lofted contour templates, has eggcrate-like structure for use in forming and checking panels.

  13. The generalized second law of thermodynamics in Hořava-Lifshitz cosmology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jamil, Mubasher; Saridakis, Emmanuel N.; Setare, M.R., E-mail: mjamil@camp.nust.edu.pk, E-mail: msaridak@phys.uoa.gr, E-mail: rezakord@ipm.ir

    2010-11-01

    We investigate the validity of the generalized second law of thermodynamics in a universe governed by Hořava-Lifshitz gravity. Under the equilibrium assumption, that is in the late-time cosmological regime, we calculate separately the entropy time-variation for the matter fluid and, using the modified entropy relation, that of the apparent horizon itself. We find that under detailed balance the generalized second law is generally valid for flat and closed geometry and it is conditionally valid for an open universe, while beyond detailed balance it is only conditionally valid for all curvatures. Furthermore, we also follow the effective approach showing that itmore » can lead to misleading results. The non-complete validity of the generalized second law could either provide a suggestion for its different application, or act as an additional problematic feature of Hořava-Lifshitz gravity.« less

  14. Magnetic properties and magnetocaloric effect of HoCo3B2 compound

    NASA Astrophysics Data System (ADS)

    Zheng, X. Q.; Xu, J. W.; Zhang, H.; Zhang, J. Y.; Wang, S. G.; Zhang, Y.; Xu, Z. Y.; Wang, L. C.; Shen, B. G.

    2018-05-01

    A sample of HoCo3B2 compound was synthesized, and the magnetic and MCE properties were investigated. Compound shows a change corresponding to R-R (R = rare earth) sublattice magnetic order transition and the transition temperature is determined to be 11.8 K (TC). The characteristic of Arrott plots with positive slope around TC was observed, indicating a second-order phase transition. Based on isothermal magnetization data, together with Maxwell's relationship, the magnetic entropy change (-ΔSM) was calculated. The maximum -ΔSM reaches 7.8, 12.7 and 14.4 J/kg K for field range of 0-2 T, 0-5 T and 0-7 T, respectively. Accordingly, the value of RC (refrigerant capacity) is 99, 289 and 432 J/kg for above field ranges. The large MCE of HoCo3B2 compound indicates its potential application for magnetic refrigeration in low temperature range.

  15. Optical spectroscopy and diode-pumped laser characteristics of codoped Tm-Ho:YLF and Tm-Ho:BaYF: a comparative analysis

    NASA Astrophysics Data System (ADS)

    Cornacchia, F.; Sani, E.; Toncelli, A.; Tonelli, M.; Marano, M.; Taccheo, S.; Galzerano, G.; Laporta, P.

    Single crystals of monoclinic BaY2F8 and tetragonal LiYF4 codoped with the same Tm3+ and Ho3+ concentrations were successfully grown by the Czochralski method. Here we present a comparative analysis of the two hosts including spectroscopic characterization and cw diode-pumped laser experiments in the 2-μm wavelength region at room temperature. The main differences between the two hosts are a lower slope efficiency associated with a much wider tuning range (2005-2094 nm) of BaY2F8 with respect to LiYF4.

  16. Easy Attachment Of Panels To A Truss

    NASA Technical Reports Server (NTRS)

    Thomson, Mark; Gralewski, Mark

    1992-01-01

    Conceptual antenna dish, solar collector, or similar structure consists of hexagonal panels supported by truss erected in field. Truss built in increments to maintain access to panel-attachment nodes. Each panel brought toward truss at angle and attached to two nodes. Panel rotated into attachment at third node.

  17. Multi-clad black display panel

    DOEpatents

    Veligdan, James T.; Biscardi, Cyrus; Brewster, Calvin

    2002-01-01

    A multi-clad black display panel, and a method of making a multi-clad black display panel, are disclosed, wherein a plurality of waveguides, each of which includes a light-transmissive core placed between an opposing pair of transparent cladding layers and a black layer disposed between transparent cladding layers, are stacked together and sawed at an angle to produce a wedge-shaped optical panel having an inlet face and an outlet face.

  18. Orbiter radiator panel solar focusing test

    NASA Technical Reports Server (NTRS)

    Howell, H. R.; Rankin, J. G.

    1983-01-01

    Test data are presented which define the area around the Orbiter radiator panels for which the solar reflections are concentrated to one-sun or more. The concave shape of the panels and their specular silver/Teflon coating causes focusing of the reflected solar energy which could have adverse heating effects on equipment or astronaut extravehicular activity (EVA) in the vicinity of the radiator panels. A room ambient test method was utilized with a one-tenth scale model of the radiator panels.

  19. Thermal-Diode Sandwich Panel

    NASA Technical Reports Server (NTRS)

    Basiulis, A.

    1986-01-01

    Thermal diode sandwich panel transfers heat in one direction, but when heat load reversed, switches off and acts as thermal insulator. Proposed to control temperature in spacecraft and in supersonic missiles to protect internal electronics. In combination with conventional heat pipes, used in solar panels and other heat-sensitive systems.

  20. 14 CFR 1259.600 - Panel description.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Panel description. 1259.600 Section 1259.600 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NATIONAL SPACE GRANT COLLEGE AND FELLOWSHIP PROGRAM Space Grant Review Panel § 1259.600 Panel description. An independent committee...

  1. VizieR Online Data Catalog: Spectra of a Holmium in the near-UV. I. Ho I. (Al-Labady+, 2017)

    NASA Astrophysics Data System (ADS)

    Al-Labady, N.; Ozdalgic, B.; Er, A.; Guzelcimen, F.; Ozturk, I. K.; Kroger, S.; Kruzins, A.; Tamanis, M.; Ferber, R.; Basar, G.

    2017-04-01

    The high-resolution spectra of Holmium (Ho) were recorded with a Fourier Transform spectrometer IFS125 HR at the Laser Centre of the University of Latvia in Riga. Two Ho spectra were recorded, one with argon (Ar) as a buffer gas and one with neon (Ne). The spectra cover the ultraviolet spectral range from 25000 up to 31530cm-1, or 317 to 400nm, respectively. (1 data file).

  2. Castro Valley High School's Solar Panels

    NASA Astrophysics Data System (ADS)

    Lew, A.; Ham, S.; Shin, Y.; Yang, W.; Lam, J.

    2014-12-01

    Solar panels are photovoltaic cells that are designed to convert the sun's kinetic energy to generate usable energy in the form of electricity. Castro Valley High School has tried to offset the cost of electricity by installing solar panels, costing the district approximately 3.29 million dollars, but have been installed incorrectly and are not operating at peak efficency. By using trigonometry we deduced that Castro Valley High School's south facing solar panels were at an incline of 10o and that the east and west facing solar panels are at an incline of 5o. By taking the averages of the optimum angles for the months of September through May, roughly when school is in session, we found that the optimum angle for south facing solar panels should be roughly 46o. This shows that Castro Valley High School has not used it's budget to its full potential due to the fact that the solar panels were haphazardly installed.

  3. A "win-win" nanoplatform: TiO2:Yb,Ho,F for NIR light-induced synergistic therapy and imaging.

    PubMed

    Zhou, Jie; Luo, Pei; Sun, Chong; Meng, Lingchang; Ye, Weiran; Chen, Shanshan; Du, Bin

    2017-03-23

    To avoid the defect of low energy transfer efficiency in core-shell UCNP-TiO 2 NPs, doping rare earth into TiO 2 and improving the photocatalytic activity of TiO 2 itself under Vis-NIR light might be a more direct and efficient strategy for high 1 O 2 production. Here, we designed a TiO 2 :Yb,Ho,F-β-CD@DTX/HA nanoplatform using TiO 2 :Yb,Ho,F as the core, β-CD as the drug carrier, hyaluronic acid (HA) as the capping agent and target, and then applied it for 808 nm induced photodynamic-chemotherapy and 980 nm upconversion fluorescence/MR imaging. The results were as follows: (i) for TiO 2 as a photosensitizer, after doping Yb, Ho, F into TiO 2 , it could directly generate reactive oxygen species under an 808 nm laser; the dopants enhanced the absorption under the UV-Vis-NIR region and increased the electron-hole pair separation. (ii) For TiO 2 as the upconversion host, F and Ho also endowed TiO 2 :Yb,Ho,F with enhanced upconversion fluorescence under a 980 nm laser and T 2 -MRI contrast performance (r 2 = 30.71 mM -1 s -1 ), respectively, thus, facilitating imaging for deep tissues. (iii) The HA shell outside of β-CD prevented the unexpected leaking of DTX, which improved the target abilities and achieved the enzyme-responsive drug release. The in vitro and in vivo studies also demonstrated the nanosystem could efficiently suppress tumor growth by combination therapy and had excellent imaging (UCL/MR) ability. Particularly, our work was the first example that utilized TiO 2 simultaneously as a photosensitizer and upconversion host, which simplified the core-shell UCNP-TiO 2 nanocomposites and reached a "win-win" cooperation in NIR-induced photodynamic therapy and UCL imaging.

  4. 78 FR 53429 - Response Systems to Adult Sexual Assault Crimes Panel (Response Systems Panel); Notice of Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... recommendations regarding how to improve the effectiveness of such systems. The Panel is interested in written and... DEPARTMENT OF DEFENSE Office of the Secretary Response Systems to Adult Sexual Assault Crimes Panel (Response Systems Panel); Notice of Federal Advisory Committee Meeting AGENCY: Department of...

  5. 78 FR 34995 - Response Systems to Adult Sexual Assault Crimes Panel (Response Systems Panel); Notice of Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... DEPARTMENT OF DEFENSE Office of the Secretary Response Systems to Adult Sexual Assault Crimes Panel (Response Systems Panel); Notice of Federal Advisory Committee Meeting AGENCY: Department of... committee meeting of the Response Systems to Adult Sexual Assault Crimes Panel. DATES: A meeting of the...

  6. The Synthesis of a Core-Shell Photocatalyst Material YF3:Ho3+@TiO2 and Investigation of Its Photocatalytic Properties

    PubMed Central

    Xu, Xuan; Zhou, Shiyu; Long, Jun; Wu, Tianhu; Fan, Zihong

    2017-01-01

    In this paper, YF3:Ho3+@TiO2 core-shell nanomaterials were prepared by hydrolysis of tetra-n-butyl titanate (TBOT) using polyvinylpyrrolidone K-30 (PVP) as the coupling agent. Characterization methods including X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) under TEM, X-ray photoelectron spectroscopy (XPS), fluorescence spectrometry, ultraviolet-visible diffuse reflectance spectroscopy, and electron spin resonance (ESR) were used to characterize the properties and working mechanism of the prepared photocatalyst material. They indicated that the core phase YF3 nanoparticles were successfully coated with a TiO2 shell and the length of the composite was roughly 100 nm. The Ho3+ single-doped YF3:Ho3+@TiO2 displayed strong visible absorption peaks with wavelengths of 450, 537, and 644 nm, respectively. By selecting these three peaks as excitation wavelengths, we could observe 288 nm (5D4→5I8) ultraviolet emission, which confirmed that there was indeed an energy transfer from YF3:Ho3+ to anatase TiO2. In addition, this paper investigated the influences of different TBOT dosages on photocatalysis performance of the as-prepared photocatalyst material. Results showed that the YF3:Ho3+@TiO2 core-shell nanomaterial was an advanced visible-light-driven catalyst, which decomposed approximately 67% of rhodamine b (RhB) and 34.6% of phenol after 10 h of photocatalysis reaction. Compared with the blank experiment, the photocatalysis efficiency was significantly improved. Finally, the visible-light-responsive photocatalytic mechanism of YF3:Ho3+@TiO2 core-shell materials and the influencing factors of photocatalytic degradation were investigated to study the apparent kinetics, which provides a theoretical basis for improving the structural design and functions of this new type of catalytic material. PMID:28772662

  7. 45 CFR 1801.23 - Recommendation by panel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Recommendation by panel. 1801.23 Section 1801.23... HARRY S. TRUMAN SCHOLARSHIP PROGRAM The Competition § 1801.23 Recommendation by panel. (a) Each Panel is... recommend additional Scholars from the States in its region. (b) A panel's recommendations are based on the...

  8. 45 CFR 1801.23 - Recommendation by panel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Recommendation by panel. 1801.23 Section 1801.23... HARRY S. TRUMAN SCHOLARSHIP PROGRAM The Competition § 1801.23 Recommendation by panel. (a) Each Panel is... recommend additional Scholars from the States in its region. (b) A panel's recommendations are based on the...

  9. Exascale Workshop Panel Report Meeting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khaleel, Mohammad A.

    2010-07-01

    The Exascale Review Panel consists of 12 scientists and engineers with experience in various aspects of high-performance computing and its application, development, and management. The Panel hear presentations by several representatives of the workshops and town meetings convened over the past few years to examine the need for exascale computation capability and the justification for a U.S. Department of Energy (DOE) program to develop such capability. This report summarizes information provided by the presenters and substantial written reports to the Panel in advance of the meeting in Washington D.C. on January 19-20, 2010. The report also summarizes the Panel's conclusionsmore » with regard to the justification of a DOE-led exascale initiative.« less

  10. High temperature structural sandwich panels

    NASA Astrophysics Data System (ADS)

    Papakonstantinou, Christos G.

    High strength composites are being used for making lightweight structural panels that are being employed in aerospace, naval and automotive structures. Recently, there is renewed interest in use of these panels. The major problem of most commercial available sandwich panels is the fire resistance. A recently developed inorganic matrix is investigated for use in cases where fire and high temperature resistance are necessary. The focus of this dissertation is the development of a fireproof composite structural system. Sandwich panels made with polysialate matrices have an excellent potential for use in applications where exposure to high temperatures or fire is a concern. Commercial available sandwich panels will soften and lose nearly all of their compressive strength temperatures lower than 400°C. This dissertation consists of the state of the art, the experimental investigation and the analytical modeling. The state of the art covers the performance of existing high temperature composites, sandwich panels and reinforced concrete beams strengthened with Fiber Reinforced Polymers (FRP). The experimental part consists of four major components: (i) Development of a fireproof syntactic foam with maximum specific strength, (ii) Development of a lightweight syntactic foam based on polystyrene spheres, (iii) Development of the composite system for the skins. The variables are the skin thickness, modulus of elasticity of skin and high temperature resistance, and (iv) Experimental evaluation of the flexural behavior of sandwich panels. Analytical modeling consists of a model for the flexural behavior of lightweight sandwich panels, and a model for deflection calculations of reinforced concrete beams strengthened with FRP subjected to fatigue loading. The experimental and analytical results show that sandwich panels made with polysialate matrices and ceramic spheres do not lose their load bearing capability during severe fire exposure, where temperatures reach several

  11. 14 CFR 1259.600 - Panel description.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Panel description. 1259.600 Section 1259.600 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NATIONAL SPACE GRANT COLLEGE AND FELLOWSHIP PROGRAM Space Grant Review Panel § 1259.600 Panel description. An independent committee, the Space...

  12. Durability of structural panels

    Treesearch

    Eddie W. Price; [Editor

    1984-01-01

    Twenty papers from the proceedings of a workshop are presented on the durability of a group of structural panels for use in roof, wall, and floor sheathing applications. The panel types are waferboard,flakeboard, strandboard, oriented structural board, and structural particleboard. A summary of the proceedings is given as the final presentation.

  13. Transfer of Ho Endonuclease and Ufo1 to the Proteasome by the UbL-UbA Shuttle Protein, Ddi1, Analysed by Complex Formation In Vitro

    PubMed Central

    Voloshin, Olga; Bakhrat, Anya; Herrmann, Sharon; Raveh, Dina

    2012-01-01

    The F-box protein, Ufo1, recruits Ho endonuclease to the SCFUfo1 complex for ubiquitylation. Both ubiquitylated Ho and Ufo1 are transferred by the UbL-UbA protein, Ddi1, to the 19S Regulatory Particle (RP) of the proteasome for degradation. The Ddi1-UbL domain binds Rpn1 of the 19S RP, the Ddi1-UbA domain binds ubiquitin chains on the degradation substrate. Here we used complex reconstitution in vitro to identify stages in the transfer of Ho and Ufo1 from the SCFUfo1 complex to the proteasome. We report SCFUfo1 complex at the proteasome formed in the presence of Ho. Subsequently Ddi1 is recruited to this complex by interaction between the Ddi1-UbL domain and Ufo1. The core of Ddi1 binds both Ufo1 and Rpn1; this interaction confers specificity of SCFUfo1 for Ddi1. The substrate-shield model predicts that Ho would protect Ufo1 from degradation and we find that Ddi1 binds Ho, Ufo1, and Rpn1 simultaneously forming a complex for transfer of Ho to the 19S RP. In contrast, in the absence of Ho, Rpn1 displaces Ufo1 from Ddi1 indicating a higher affinity of the Ddi1-UbL for the 19S RP. However, at high Rpn1 levels there is synergistic binding of Ufo1 to Ddi1 that is dependent on the Ddi1-UbA domain. Our interpretation is that in the absence of substrate, the Ddi1-UbL binds Rpn1 while the Ddi1-UbA binds ubiquitin chains on Ufo1. This would promote degradation of Ufo1 and disassembly of SCFUfo1 complexes. PMID:22815701

  14. Effect of boundary conditions and panel geometry on the response of laminated panels subjected to transverse pressure loads

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.

    1993-01-01

    The behavior of thin laminated flat and curved panels subjected to transverse pressure and inplane loads is considered. The effects of panel geometry, boundary conditions and laminate stacking sequence on the response of panels subjected to transverse pressure loads up to 12.4 N/sq cm is presented. The response of thin laminated panels is evaluated analytically and selected results are compared with test data. A parametric study of the deformation and strain responses of panels with radius of curvature ranging from 20 to 305 cm is presented. The combination of inplane tensile and pressure loads is also considered.

  15. Sound transmission loss of composite sandwich panels

    NASA Astrophysics Data System (ADS)

    Zhou, Ran

    Light composite sandwich panels are increasingly used in automobiles, ships and aircraft, because of the advantages they offer of high strength-to-weight ratios. However, the acoustical properties of these light and stiff structures can be less desirable than those of equivalent metal panels. These undesirable properties can lead to high interior noise levels. A number of researchers have studied the acoustical properties of honeycomb and foam sandwich panels. Not much work, however, has been carried out on foam-filled honeycomb sandwich panels. In this dissertation, governing equations for the forced vibration of asymmetric sandwich panels are developed. An analytical expression for modal densities of symmetric sandwich panels is derived from a sixth-order governing equation. A boundary element analysis model for the sound transmission loss of symmetric sandwich panels is proposed. Measurements of the modal density, total loss factor, radiation loss factor, and sound transmission loss of foam-filled honeycomb sandwich panels with different configurations and thicknesses are presented. Comparisons between the predicted sound transmission loss values obtained from wave impedance analysis, statistical energy analysis, boundary element analysis, and experimental values are presented. The wave impedance analysis model provides accurate predictions of sound transmission loss for the thin foam-filled honeycomb sandwich panels at frequencies above their first resonance frequencies. The predictions from the statistical energy analysis model are in better agreement with the experimental transmission loss values of the sandwich panels when the measured radiation loss factor values near coincidence are used instead of the theoretical values for single-layer panels. The proposed boundary element analysis model provides more accurate predictions of sound transmission loss for the thick foam-filled honeycomb sandwich panels than either the wave impedance analysis model or the

  16. 30 CFR 77.310 - Control panels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Control panels. 77.310 Section 77.310 Mineral....310 Control panels. (a) All thermal dryer system control panels constructed after June 30, 1971 shall... manner as to minimize vibration. (b) A schematic diagram containing legends which show the location of...

  17. 30 CFR 77.310 - Control panels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Control panels. 77.310 Section 77.310 Mineral....310 Control panels. (a) All thermal dryer system control panels constructed after June 30, 1971 shall... manner as to minimize vibration. (b) A schematic diagram containing legends which show the location of...

  18. 30 CFR 77.310 - Control panels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Control panels. 77.310 Section 77.310 Mineral....310 Control panels. (a) All thermal dryer system control panels constructed after June 30, 1971 shall... each thermocouple, pressure tap, or other control or gaging instrument in the drying system shall be...

  19. 30 CFR 77.310 - Control panels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Control panels. 77.310 Section 77.310 Mineral....310 Control panels. (a) All thermal dryer system control panels constructed after June 30, 1971 shall... each thermocouple, pressure tap, or other control or gaging instrument in the drying system shall be...

  20. 30 CFR 77.310 - Control panels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Control panels. 77.310 Section 77.310 Mineral....310 Control panels. (a) All thermal dryer system control panels constructed after June 30, 1971 shall... each thermocouple, pressure tap, or other control or gaging instrument in the drying system shall be...

  1. Determination of the cross section for (n,p) and (n,α) reactions on (165)Ho at 13.5 and 14.8MeV.

    PubMed

    Luo, Junhua; An, Li; Jiang, Li; He, Long

    2015-04-01

    Activation cross-sections for the (165)Ho(n,p)(165)Dy and (165)Ho(n,α)(162)Tb reactions were measured by means of the activation method at 13.5 and 14.8MeV, to resolve inconsistencies in existing data. A neutron beam produced via the (3)H(d,n)(4)He reaction was used. Statistical model calculations were performed using the nuclear-reaction codes EMPIRE-3.2 Malta and TALYS-1.6 with default parameters, at neutron energies varying from the reaction threshold to 20MeV. Results are also discussed and compared with some corresponding values found in the literature. The calculational results on the (165)Ho(n,α)(162)Tb reaction agreed fairly well with experimental data, but there were large discrepancies in the results for the (165)Ho(n,p)(165)Dy reaction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Modeling Photodetachment from HO2- Using the pd Case of the Generalized Mixed Character Molecular Orbital Model

    NASA Astrophysics Data System (ADS)

    Blackstone, Christopher C.; Sanov, Andrei

    2016-06-01

    Using the generalized model for photodetachment of electrons from mixed-character molecular orbitals, we gain insight into the nature of the HOMO of HO2- by treating it as a coherent superpostion of one p- and one d-type atomic orbital. Fitting the pd model function to the ab initio calculated HOMO of HO2- yields a fractional d-character, γp, of 0.979. The modeled curve of the anisotropy parameter, β, as a function of electron kinetic energy for a pd-type mixed character orbital is matched to the experimental data.

  3. Electronic and Crystalline Structure, Magnetic Response, and Optical Characterization of Rare-Earth Ruthenate Sr2HoRuO6

    NASA Astrophysics Data System (ADS)

    Velásquez Moya, X. A.; Cardona, R.; Villa Hernández, J. I.; Landínez Téllez, D. A.; Roa-Rojas, J.

    2018-03-01

    Sr2HoRuO6 ceramic has been synthesized and its structural, morphological, magnetic, optical, and electronic properties studied. Rietveld refinement of x-ray diffraction patterns revealed that this oxide material crystallizes in monoclinic perovskite structure in space group P2 1 /n (no. 14). Scanning electron microscopy revealed polycrystalline surface morphology. x-Ray dispersive spectroscopy suggested that Sr2HoRuO6 was obtained with expected stoichiometry. Magnetic susceptibility curves as a function of temperature revealed ferrimagnetic feature of this material below the Néel temperature T N of 14 K. Evidence of magnetic disorder was provided by the irreversibility observed in the zero-field-cooled and field-cooled responses of the susceptibility below T irr = 169 K. Analysis of the diffuse reflectance spectrum suggested that this material behaves as a semiconductor with energy gap E g of 1.38 eV. Results of band structure and density-of-states calculations are in agreement with the interpretation of Sr2HoRuO6 as a semiconductor. The ferrimagnetic behavior is interpreted as due to exchange mechanisms of d-f (Ru-O-Ho) electrons. The effective magnetic moment calculated from density functional theory was 93.5% of the experimental value obtained from Curie-Weiss fitting of the susceptibility curve.

  4. Containment-enhanced Ho:YAG photofragmentation of soft tissues

    NASA Astrophysics Data System (ADS)

    Christens-Barry, William A.; Guarnieri, Michael; Carson, Benjamin S.

    1998-01-01

    Laser surgery of soft tissue can exploit the power of brief, intense pulses of light to cause localized disruption of tissue with minimal effect upon surrounding tissue. In particular, studies of Ho:YAG laser surgery have shown that the effects of cavitation upon tissues and bone depend upon the physical composition of structures in the vicinity of the surgical site. For photofragmentation of occluding structures within catheters and other implant devices, it is possible to exploit the particular geometry of the catheter to amplify the effects of photofragmentation beyond those seen in bulk tissue. A Ho:YAG laser was used to photofragment occlusive material (tissue and tissue analogs) contained in glass capillary tubing and catheter tubing of the kind used in ventricular shunt implants for the management of hydrocephalus. Occluded catheters obtained from patient explants were also employed. Selection of operational parameters used in photoablation and photofragmentation of soft tissue must consider the physical composition and geometry of the treatment site. In the present case, containment of the soft tissue within relatively inelastic catheters dramatically alters the extent of photofragmentation relative to bulk (unconstrained) material. Our results indicate that the disruptive effect of cavitation bubbles is increased in catheters, due to the rapid displacement of material by cavitation bubbles comparable in size to the inner diameter of the catheter. The cylindrical geometry of the catheter lumen may additionally influence the propagation of acoustic shock waves that result from the collapse of the condensing cavitation bubbles.

  5. Impact of pulse duration on Ho:YAG laser lithotripsy: fragmentation and dusting performance.

    PubMed

    Bader, Markus J; Pongratz, Thomas; Khoder, Wael; Stief, Christian G; Herrmann, Thomas; Nagele, Udo; Sroka, Ronald

    2015-04-01

    In vitro investigations of Ho:YAG laser-induced stone fragmentation were performed to identify potential impacts of different pulse durations on stone fragmentation characteristics. A Ho:YAG laser system (Swiss LaserClast, EMS S.A., Nyon, Switzerland) with selectable long or short pulse mode was tested with regard to its fragmentation and laser hardware compatibility properties. The pulse duration is depending on the specific laser parameters. Fragmentation tests (hand-held, hands-free, single-pulse-induced crater) on artificial BEGO stones were performed under reproducible experimental conditions (fibre sizes: 365 and 200 µm; laser settings: 10 W through combinations of 0.5, 1, 2 J/pulse and 20, 10, 5 Hz, respectively). Differences in fragmentation rates between the two pulse duration regimes were detected with statistical significance for defined settings. Hand-held and motivated Ho:YAG laser-assisted fragmentation of BEGO stones showed no significant difference between short pulse mode and long pulse mode, neither in fragmentation rates nor in number of fragments and fragment sizes. Similarly, the results of the hands-free fragmentation tests (with and without anti-repulsion device) showed no statistical differences between long pulse and short pulse modes. The study showed that fragmentation rates for long and short pulse durations at identical power settings remain at a comparable level. Longer holmium laser pulse duration reduces stone pushback. Therefore, longer laser pulses may result in better clinical outcome of laser lithotripsy and more convenient handling during clinical use without compromising fragmentation effectiveness.

  6. Development of Electrostatically Clean Solar Array Panels

    NASA Technical Reports Server (NTRS)

    Stern, Theodore G.

    2000-01-01

    Certain missions require Electrostatically Clean Solar Array (ECSA) panels to establish a favorable environment for the operation of sensitive scientific instruments. The objective of this program was to demonstrate the feasibility of an ECSA panel that minimizes panel surface potential below 100mV in LEO and GEO charged particle environments, prevents exposure of solar cell voltage and panel insulating surfaces to the ambient environment, and provides an equipotential, grounded structure surrounding the entire panel. An ECSA panel design was developed that uses a Front Side Aperture-Shield (FSA) that covers all inter-cell areas with a single graphite composite laminate, composite edge clips for connecting the FSA to the panel substrate, and built-in tabs that interconnect the FSA to conductive coated coverglasses using a conductive adhesive. Analysis indicated the ability of the design to meet the ECSA requirements. Qualification coupons and a 0.5m x 0.5m prototype panel were fabricated and tested for photovoltaic performance and electrical grounding before and after exposure to acoustic and thermal cycling environments. The results show the feasibility of achieving electrostatic cleanliness with a small penalty in mass, photovoltaic performance and cost, with a design is structurally robust and compatible with a wide range of current solar panel technologies.

  7. Rate coefficients for the reaction of formaldehyde with HO2 radicals from fluorescence spectroscopy of HOCH2OO radicals

    NASA Astrophysics Data System (ADS)

    Bunkan, Arne; Amédro, Damien; Crowley, John

    2017-04-01

    The reaction of formaldehyde with HO2 radicals constitutes a minor, but significant sink of formaldehyde in the troposphere as well as a possible interference in other formaldehyde photooxidation experiments. HCHO + HO2 ⇌ HOCH2OO (1) Due to the difficulty of simultaneously monitoring the reactant and product concentrations while preventing interfering secondary chemistry, there is a considerable uncertainty in the literature values for the reaction rate coefficients. We have used two photon, excited fragment spectroscopy (TPEFS), originally developed for monitoring HNO3 formation in kinetic experiments, to monitor the formation of the HOCH2OO radical. Dispersed and single wavelength fluorescence emission following the 193 nm photolysis of HOCH2OO have been recorded and analysed. Characterisation of the method is presented along with rate coefficients for the reaction of HCHO with HO2 radicals at tropospheric temperatures.

  8. 77 FR 66441 - North American Free Trade Agreement, Article 1904 NAFTA Panel Reviews; First Request for Panel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-05

    ..., Article 1904 NAFTA Panel Reviews; First Request for Panel Review AGENCY: NAFTA Secretariat, United States... Panel Review with the United States Section of the NAFTA Secretariat pursuant to Article 1904 of the... antidumping or countervailing duty law of the country that made the determination. Under Article 1904 of the...

  9. 76 FR 10005 - North American Free Trade Agreement, Article 1904 NAFTA Panel Reviews; Request for Panel Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-23

    ..., Article 1904 NAFTA Panel Reviews; Request for Panel Review AGENCY: NAFTA Secretariat, United States... Secretariat pursuant to Article 1904 of the North American Free Trade Agreement. Panel Review was requested of... countervailing duty law of the country that made the determination. Under Article 1904 of the Agreement, which...

  10. 75 FR 13494 - North American Free-Trade Agreement, Article 1904; NAFTA Panel Reviews; Request for Panel Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ..., Article 1904; NAFTA Panel Reviews; Request for Panel Review AGENCY: NAFTA Secretariat, United States... Secretariat pursuant to Article 1904 of the North American Free Trade Agreement. Panel Review was requested of... Article 1904 of the Agreement, which came into force on January 1, 1994, the Government of the United...

  11. 77 FR 26252 - North American Free Trade Agreement, Article 1904 NAFTA Panel Reviews; First Request for Panel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ..., Article 1904 NAFTA Panel Reviews; First Request for Panel Review AGENCY: NAFTA Secretariat, United States... for Panel Review with the United States Section of the NAFTA Secretariat pursuant to Article 1904 of... law of the country that made the determination. Under Article 1904 of the Agreement, which came into...

  12. 75 FR 82375 - North American Free Trade Agreement, Article 1904 NAFTA Panel Reviews; Request for Panel Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-30

    ..., Article 1904 NAFTA Panel Reviews; Request for Panel Review AGENCY: NAFTA Secretariat, United States... to Article 1904 of the North American Free Trade Agreement. Second and Third Requests for Panel... Article 1904 of the Agreement, which came into force on January 1, 1994, the Government of the United...

  13. Law Panel in action.

    PubMed

    Odulana, J

    In September 1976 the Africa Regional Council (ARC) of IPPF created a Law Panel to 1) advise the ARC on the emphasis of laws and parenthood programs in the region, 2) investigate legal obstacles to family planning and ways of removing them, 3) institute a monitoring service on laws and court decisions affecting planned parenthood, and 4) prepare a list of lawyers and legal reformers by country. The panel has 1) recommended adoption of an IPPF Central Medical Committee and Central Law Panel statement on sterilization, adolescent fertility control, and the use of medical and auxiliary personnel in family planning services with guidelines for Africa; 2) appointed National Legal Correspondents to carry on the monitoring service mentioned above in 18 countries; and 3) discussed solutions to problems in delivering family planning services with family planning associations in Tanzania, Zambia, Mauritius, Madagascar, and Kenya. Laws governing family planning education and services, marriage, divorce, and maternity benefits in these countries are summarized. In 1978 the panel will hold 2 workshops on law and the status of women.

  14. Translation and validation of the Spanish version of the Health of the Nation Outcome Scales for People with Learning Disabilities (HoNOS-LD).

    PubMed

    Esteba-Castillo, Susanna; Torrents-Rodas, David; García-Alba, Javier; Ribas-Vidal, Núria; Novell-Alsina, Ramon

    2016-12-21

    The Health of the Nation Outcome Scales for People with Learning Disabilities (HoNOS-LD) is a brief instrument that assesses functioning in people with intellectual development disorder and mental health problems/behaviour disorders. The aim of the present study was to examine the evidence on the validity of the scores based on the Spanish version of the HoNOS-LD. The study included 111 participants that were assessed by the Spanish version of the HoNOS-LD and other questionnaires that measured different variables related to the scale. Thirty-three participants were assessed by 2 examiners, and retested 7 days later, in order to study inter-examiner reliability and test-retest reliabilities. Based on clinical and conceptual criteria, and on the results of the parallel analysis, a factorial solution with one factor was selected. Internal consistency was good (Omega coefficient of 0.87). Inter-examiner and test-retest reliabilities were excellent (intraclass correlation coefficients of 0.95 and 0.98, respectively). Correlations between sections of the HoNOS-LD and the related instruments showed the expected direction, and were highly significant (P<.001), and the HoNOS-LD score increased with the intensity of the support required by the participants. These results showed evidence of the validity of association with other external variables. The Spanish version of the HoNOS-LD is a brief, valid and reliable instrument, which will enable a routine assessment of functioning for different uses, including diagnosis and intervention. Copyright © 2016 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. High power single-longitudinal-mode Ho:YLF unidirectional ring laser based on a composite structure of acousto-optic device and wave plate

    NASA Astrophysics Data System (ADS)

    Dai, T. Y.; Fan, Z. G.; Wu, J.; Ju, Y. L.; Yao, B. Q.; Zhang, Z. G.; Teng, K.; Xu, X. G.; Duan, X. M.

    2017-05-01

    We report a unidirectional single-longitudinal-mode Ho:YLF ring laser. An acousto-optic modulator and two half-wave plates were used to enforce the Ho:YLF ring laser in a unidirectional operation. The single-longitudinal-mode output power could reach 3.73 W successfully when the incident pump power was 16.4 W. The corresponding slope efficiency was 27.1%. The wavelength of the single-longitudinal-mode Ho:YLF ring laser was 2063.8 nm. The M2 factor was 1.12. The results illustrated that the single-longitudinal-mode output power could be further enhanced by increasing the radio frequency power of the acousto-optic modulator.

  16. Aspirin suppresses neuronal apoptosis, reduces tissue inflammation, and restrains astrocyte activation by activating the Nrf2/HO-1 signaling pathway.

    PubMed

    Wei, Wang; Shurui, Chen; Zipeng, Zhou; Hongliang, Dai; Hongyu, Wang; Yuanlong, Li; Kang, Zhou; Zhaoliang, Shen; Yue, Guo; Chang, Liu; Mei, Xifan

    2018-05-02

    The nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element signaling pathway plays a substantial role in preventing oxidative stress-related diseases. Aspirin has been shown to exert several pharmacological effects by inducing the expression of the heme oxygenase-1 (HO-1) protein. However, the effects of aspirin on spinal cord injury (SCI) have rarely been studied. Therefore, we sought to investigate the neuroprotective effects of aspirin after SCI. We employed a spinal cord contusion model in Sprague-Dawley rats, and aspirin was administered intraperitoneally for 7 days. Nissl staining showed that the aspirin treatment significantly reduced the loss of motor neurons after SCI compared with vehicle-treated animals. The expression of Nrf2, quinine oxidoreductase 1, and HO-1 proteins was increased in aspirin-treated animals after SCI compared with the vehicle group. In addition, aspirin simultaneously decreased the expression of inflammation-related proteins, such as tumor necrosis factor-α and interleukin-6 after SCI. Moreover, the ratio of apoptotic neurons in the anterior horn and the levels of the apoptosis-related proteins caspase-3, cleaved caspase-3, and Bax were significantly decreased in the aspirin group compared with the vehicle group. Immunofluorescence staining was used to detect the colocalization of NeuN and HO-1, and the results showed that aspirin significantly increased expression of the HO-1 protein in neurons. In addition, western blots and immunofluorescence staining showed aspirin restrained astrocyte activation. In conclusion, aspirin induces neuroprotective effects by inhibiting astrocyte activation and apoptosis after SCI through the activation of the Nrf2/HO-1 signaling pathway.

  17. Near-infrared kinetic spectroscopy of the HO2 and C2H5O2 self-reactions and cross reactions.

    PubMed

    Noell, A C; Alconcel, L S; Robichaud, D J; Okumura, M; Sander, S P

    2010-07-08

    The self-reactions and cross reactions of the peroxy radicals C2H5O2 and HO2 were monitored using simultaneous independent spectroscopic probes to observe each radical species. Wavelength modulation (WM) near-infrared (NIR) spectroscopy was used to detect HO2, and UV absorption monitored C2H5O2. The temperature dependences of these reactions were investigated over a range of interest to tropospheric chemistry, 221-296 K. The Arrhenius expression determined for the cross reaction, k2(T) = (6.01(-1.47)(+1.95)) x 10(-13) exp((638 +/- 73)/T) cm3 molecules(-1) s(-1) is in agreement with other work from the literature. The measurements of the HO2 self-reaction agreed with previous work from this lab and were not further refined. The C2H5O2 self-reaction is complicated by secondary production of HO2. This experiment performed the first direct measurement of the self-reaction rate constant, as well as the branching fraction to the radical channel, in part by measurement of the secondary HO2. The Arrhenius expression for the self-reaction rate constant is k3(T) = (1.29(-0.27)(+0.34)) x 10(-13)exp((-23 +/- 61)/T) cm3 molecules(-1) s(-1), and the branching fraction value is alpha = 0.28 +/- 0.06, independent of temperature. These values are in disagreement with previous measurements based on end product studies of the branching fraction. The results suggest that better characterization of the products from RO2 self-reactions are required.

  18. Stone Retropulsion with Ho: YAG and Tm: YAG Lasers: A Clinical Practice-Oriented Experimental Study.

    PubMed

    Kamal, Wissam; Kallidonis, Panagiotis; Koukiou, Georgia; Amanatides, Lefteris; Panagopoulos, Vasileios; Ntasiotis, Pantelis; Liatsikos, Evangelos

    2016-11-01

    To compare the retropulsion of stones with the use of holmium: yttrium aluminum garnet (Ho: YAG) laser and thulium: yttrium aluminum garnet (Tm: YAG) laser in settings that could be used in clinical practice. The experimental configuration included a glass tube set in a water bath filled with physiologic saline. Plaster of Paris stones were inserted in the tube. Tm: YAG and Ho: YAG laser systems were used along with a high-speed slow-motion camera. The lasers were activated with different settings. The displacement of the stone was measured according to a custom-made algorithm. Ho: YAG: the retropulsion of stones was the lowest with the energy setting of 0.5 J and the frequency of 20 Hz with long pulse duration. The highest retropulsion was observed in the case of 3 J, 5 Hz, and short pulse. Tm: YAG: the retropulsion of stones was the lowest with the energy setting of 1 J and the frequency of 10 Hz with either long or short pulse duration. Practically, there was no retropulsion at all. The highest retropulsion was observed in the case of 8 J, 5 Hz, and short pulse. Ho: YAG laser has a linear increase in stone retropulsion with increased pulse energy. On the other hand, the retropulsion rate was kept to the minimum with Tm: YAG as much as the energy level of 8 J. The activation of lasers with short pulse resulted in further displacement of the stone. Lower frequency with the same power setting seemed to result in further stone retropulsion. Higher power with the same frequency setting resulted in further displacement of the stone.

  19. Thermal effects of Ho: YAG laser lithotripsy: real-time evaluation in an in vitro model.

    PubMed

    Hein, Simon; Petzold, Ralf; Schoenthaler, Martin; Wetterauer, Ulrich; Miernik, Arkadiusz

    2018-04-24

    To evaluate the thermal effect of Ho:YAG laser lithotripsy in a standardized in vitro model via real-time temperature measurement. Our model comprised a 20 ml test tube simulating the renal pelvis that was immersed in a 37 °C water bath. Two different laser fibers [FlexiFib (15-45 W), RigiFib 1000 (45-100 W), LISA laser products OHG, Katlenburg-Lindau, Germany] were placed in the test tube. An Ho:YAG 100 W laser was used in all experiments (LISA). Each experiment involved 120 s of continuous laser application, and was repeated five times. Different laser settings (high vs. low frequency, high vs. low energy, and long vs. short pulse duration), irrigation rates (0 up to 100 ml/min, realized by several pumps), and human calcium oxalate stone samples were analyzed. Temperature data were acquired by a real-time data logger with thermocouples (PICO Technology, Cambridgeshire, UK). Real-time measurements were assessed using MatLab ® . Laser application with no irrigation results in a rapid increase in temperature up to ∆28 K, rising to 68 °C at 100 W. Low irrigation rates yield significantly higher temperature outcomes. Higher irrigation rates result immediately in a lower temperature rise. High irrigation rates of 100 ml/min result in a temperature rise of 5 K at the highest laser power setting (100 W). Ho:YAG laser lithotripsy might be safe provided that there is sufficient irrigation. However, high power and low irrigation resulted in potentially tissue-damaging temperatures. Laser devices should, therefore, always be applied in conjunction with continuous, closely monitored irrigation whenever performing Ho:YAG laser lithotripsy.

  20. Heat Pipe Thermal Conditioning Panel

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.

    1973-01-01

    The technology involved in designing and fabricating a heat pipe thermal conditioning panel to satisfy a broad range of thermal control system requirements on NASA spacecraft is discussed. The design specifications were developed for a 30 by 30 inch heat pipe panel. The fundamental constraint was a maximum of 15 gradient from source to sink at 300 watts input and a flux density of 2 watts per square inch. The results of the performance tests conducted on the panel are analyzed.

  1. Experimental infection of calves, sheep, goats and pigs with HoBi-like viruses by direct inoculation or exposure to persistently infected calves

    USDA-ARS?s Scientific Manuscript database

    HoBi-like viruses are an emerging species of pestiviruses associated with respiratory and reproductive disease in cattle and in water buffaloes. Although cattle appear to be the main natural hosts, little is know about the potential for HoBi-like viruses to be transmitted to other livestock. In t...

  2. Activation of Nrf2/HO-1signaling pathway involves the anti-inflammatory activity of magnolol in Porphyromonas gingivalis lipopolysaccharide-stimulated mouse RAW 264.7 macrophages.

    PubMed

    Lu, Sheng-Hua; Hsu, Wen-Lin; Chen, Tso-Hsiao; Chou, Tz-Chong

    2015-12-01

    Magnolol isolated from Magnolia officinalis, a Chinese medical herb, exhibits an anti-inflammatory activity and a protective effect against periodontitis. The inflammation caused by lipopolysaccharide (LPS) from Porphyromonas gingivalis (P. gingivalis) has been considered a key inducer in the development of periodontitis. In this study, we investigated whether magnolol inhibits P. gingivalis LPS-evoked inflammatory responses in RAW 264.7 macrophages and the involvement of heme oxygenase-1 (HO-1). Magnolol significantly activated p38 MAPK, Nrf-2/HO-1 cascade and reactive oxygen species (ROS) formation. Notably, the Nrf-2 activation and HO-1 induction by magnolol were greatly diminished by blocking p38 MAPK activity and ROS production. Furthermore, in P. gingivalis LPS-stimulated macrophages, magnolol treatment remarkably inhibited the inflammatory responses evidenced by suppression of pro-inflammatory cytokine, prostaglandin E2, nitrite formation, and the expression of inducible nitric oxide synthase and cyclooxygenase-2, as well as NF-κB activation accompanied by a significant elevation of Nrf-2 nuclear translocation and HO-1 expression/activity. However, inhibiting HO-1 activity with tin protoporphyrin IX markedly reversed the anti-inflammatory effects of magnolol. Collectively, these findings provide a novel mechanism by which magnolol inhibits P. gingivalis LPS-induced inflammation in macrophages is at least partly mediated by HO-1 activation, and thereby promoting its clinical use in periodontitis. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Panel 4: Report of the Microbiology Panel

    PubMed Central

    Barenkamp, Stephen J.; Chonmaitree, Tasnee; Hakansson, Anders P.; Heikkinen, Terho; King, Samantha; Nokso-Koivisto, Johanna; Novotny, Laura A.; Patel, Janak A.; Pettigrew, Melinda; Swords, W. Edward

    2017-01-01

    Objective To perform a comprehensive review of the literature from July 2011 until June 2015 on the virology and bacteriology of otitis media in children. Data Sources PubMed database of the National Library of Medicine. Review Methods Two subpanels comprising experts in the virology and bacteriology of otitis media were created. Each panel reviewed the relevant literature in the fields of virology and bacteriology and generated draft reviews. These initial reviews were distributed to all panel members prior to meeting together at the Post-symposium Research Conference of the 18th International Symposium on Recent Advances in Otitis Media, National Harbor, Maryland, in June 2015. A final draft was created, circulated, and approved by all panel members. Conclusions Excellent progress has been made in the past 4 years in advancing our understanding of the microbiology of otitis media. Numerous advances were made in basic laboratory studies, in animal models of otitis media, in better understanding the epidemiology of disease, and in clinical practice. Implications for Practice (1) Many viruses cause acute otitis media without bacterial coinfection, and such cases do not require antibiotic treatment. (2) When respiratory syncytial virus, metapneumovirus, and influenza virus peak in the community, practitioners can expect to see an increase in clinical otitis media cases. (3) Biomarkers that predict which children with upper respiratory tract infections will develop otitis media may be available in the future. (4) Compounds that target newly identified bacterial virulence determinants may be available as future treatment options for children with otitis media. PMID:28372529

  4. Panel 4: Report of the Microbiology Panel.

    PubMed

    Barenkamp, Stephen J; Chonmaitree, Tasnee; Hakansson, Anders P; Heikkinen, Terho; King, Samantha; Nokso-Koivisto, Johanna; Novotny, Laura A; Patel, Janak A; Pettigrew, Melinda; Swords, W Edward

    2017-04-01

    Objective To perform a comprehensive review of the literature from July 2011 until June 2015 on the virology and bacteriology of otitis media in children. Data Sources PubMed database of the National Library of Medicine. Review Methods Two subpanels comprising experts in the virology and bacteriology of otitis media were created. Each panel reviewed the relevant literature in the fields of virology and bacteriology and generated draft reviews. These initial reviews were distributed to all panel members prior to meeting together at the Post-symposium Research Conference of the 18th International Symposium on Recent Advances in Otitis Media, National Harbor, Maryland, in June 2015. A final draft was created, circulated, and approved by all panel members. Conclusions Excellent progress has been made in the past 4 years in advancing our understanding of the microbiology of otitis media. Numerous advances were made in basic laboratory studies, in animal models of otitis media, in better understanding the epidemiology of disease, and in clinical practice. Implications for Practice (1) Many viruses cause acute otitis media without bacterial coinfection, and such cases do not require antibiotic treatment. (2) When respiratory syncytial virus, metapneumovirus, and influenza virus peak in the community, practitioners can expect to see an increase in clinical otitis media cases. (3) Biomarkers that predict which children with upper respiratory tract infections will develop otitis media may be available in the future. (4) Compounds that target newly identified bacterial virulence determinants may be available as future treatment options for children with otitis media.

  5. Nonlinear flutter analysis of composite panels

    NASA Astrophysics Data System (ADS)

    An, Xiaomin; Wang, Yan

    2018-05-01

    Nonlinear panel flutter is an interesting subject of fluid-structure interaction. In this paper, nonlinear flutter characteristics of curved composite panels are studied in very low supersonic flow. The composite panel with geometric nonlinearity is modeled by a nonlinear finite element method; and the responses are computed by the nonlinear Newmark algorithm. An unsteady aerodynamic solver, which contains a flux splitting scheme and dual time marching technology, is employed in calculating the unsteady pressure of the motion of the panel. Based on a half-step staggered coupled solution, the aeroelastic responses of two composite panels with different radius of R = 5 and R = 2.5 are computed and compared with each other at different dynamic pressure for Ma = 1.05. The nonlinear flutter characteristics comprising limited cycle oscillations and chaos are analyzed and discussed.

  6. Spectral properties and anti-Stokes luminescence of TeO2-BaF2:Ho3+, Ho3+/Yb3+ ceramics and glass excited by 1.9-μm radiation of a Tm:LiYF4 laser

    NASA Astrophysics Data System (ADS)

    Savikin, A. P.; Egorov, A. S.; Budruev, A. V.; Perunin, I. Yu.; Krasheninnikova, O. V.; Grishin, I. A.

    2017-07-01

    We demonstrate the up-conversion of Tm:LiYF4 infrared (IR) laser radiation with 1908-nm wavelength into visible light with a spectral maximum at 650 nm by ceramics with a composition of (100 - x)TeO2- xBaF2 - 1 wt % HoF3- yYbF3, where x = 20, 30, or 40 mol % and y = 0 or 0.5 wt %. The samples of 60TeO2-40BaF2 - 1 wt % HoF3 - 0.5 wt % YbF3 exhibited anti-Stokes luminescence at a threshold radiation power density of 1.0-1.5 W cm-2.

  7. Panel cutting method: new approach to generate panels on a hull in Rankine source potential approximation

    NASA Astrophysics Data System (ADS)

    Choi, Hee-Jong; Chun, Ho-Hwan; Park, Il-Ryong; Kim, Jin

    2011-12-01

    In the present study, a new hull panel generation algorithm, namely panel cutting method, was developed to predict flow phenomena around a ship using the Rankine source potential based panel method, where the iterative method was used to satisfy the nonlinear free surface condition and the trim and sinkage of the ship was taken into account. Numerical computations were performed to investigate the validity of the proposed hull panel generation algorithm for Series 60 (CB=0.60) hull and KRISO container ship (KCS), a container ship designed by Maritime and Ocean Engineering Research Institute (MOERI). The computational results were validated by comparing with the existing experimental data.

  8. α-Lipoic Acid Promotes Neurological Recovery After Ischemic Stroke by Activating the Nrf2/HO-1 Pathway to Attenuate Oxidative Damage.

    PubMed

    Lv, Chengmei; Maharjan, Surendra; Wang, Qingqing; Sun, Yongxin; Han, Xu; Wang, Shan; Mao, Zhengchun; Xin, Yanming; Zhang, Bing

    2017-01-01

    Alpha-lipoic acid (α-LA) has been demonstrated to be protective against cerebral ischemia injury. Herein, we investigate the neuroprotective effect and underlying mechanisms of α-LA. In vivo study, α-LA was administered intravenously upon reperfusion of transient middle cerebral artery occlusion. Garcia score was used to evaluate neurologic recovery. Infarct volume was examined by TTC staining, and oxidative damage was evaluated by ELISA assay. In an in vitro study, neurons were pretreated with α-LA at different doses and then subjected to OGD. Lentiviral vectors were applied to knockdown nuclear factor-erythroid 2-related factor-2 (Nrf2) or heme oxygenase-1 (HO-1). Cell viability was measured using CCK8. Protein expression was evaluated using western blot, and immunofluorescence staining was assessed. α-LA significantly reduced the infarct volume, brain edema, and oxidative damage and promoted neurologic recovery in rats. Pretreatment of α-LA caused an obvious increase in cell viability and a decrease in intracellular reactive oxygen species. Western blot analyses and immunofluorescence staining demonstrated a distinct increase in Nrf2 and HO-1 protein expression. Conversely, knockdown of Nrf2 or HO-1 resulted in the down-regulation of HO-1 protein and inhibited the neuroprotective effect of α-LA. α-LA treatment is neuroprotective and promotes functional recovery after ischemic stroke by attenuating oxidative damage, which is partially mediated by the Nrf2/HO-1 pathway. © 2017 The Author(s). Published by S. Karger AG, Basel.

  9. The upconversion luminescence and magnetism in Yb3+/Ho3+ co-doped LaF3 nanocrystals for potential bimodal imaging

    NASA Astrophysics Data System (ADS)

    Syamchand, Sasidharanpillai S.; George, Sony

    2016-12-01

    Biocompatible upconversion nanoparticles with multifunctional properties can serve as potential nanoprobes for multimodal imaging. Herein, we report an upconversion nanocrystal based on lanthanum fluoride which is developed to address the imaging modalities, upconversion luminescence imaging and magnetic resonance imaging (MRI). Lanthanide ions (Yb3+ and Ho3+) doped LaF3 nanocrystals (LaF3 Yb3+/Ho3+) are fabricated through a rapid microwave-assisted synthesis. The hexagonal phase LaF3 nanocrystals exhibit nearly spherical morphology with average diameter of 9.8 nm. The inductively coupled plasma mass spectrometry (ICP-MS) analysis estimated the doping concentration of Yb3+ and Ho3+ as 3.99 and 0.41%, respectively. The nanocrystals show upconversion luminescence when irradiated with near-infrared (NIR) photons of wavelength 980 nm. The emission spectrum consists of bands centred at 542, 645 and 658 nm. The stronger green emission at 542 nm and the weak red emissions at 645 and 658 nm are assigned to 5S2 → 5I8 and 5F5 → 5I8 transitions of Ho3+, respectively. The pump power dependence of luminescence intensity confirmed the two-photon upconversion process. The nanocrystals exhibit paramagnetism due to the presence of lanthanide ion dopant Ho3+ and the magnetization is 19.81 emu/g at room temperature. The nanocrystals exhibit a longitudinal relaxivity ( r 1) of 0.12 s-1 mM-1 and transverse relaxivity ( r 2) of 28.18 s-1 mM-1, which makes the system suitable for developing T2 MRI contrast agents based on holmium. The LaF3 Yb3+/Ho3+ nanocrystals are surface modified by PEGylation to improve biocompatibility and enhance further functionalisation. The PEGylated nanocrystals are found to be non-toxic up to 50 μg/mL for 48 h of incubation, which is confirmed by the MTT assay as well as morphological studies in HeLa cells. The upconversion luminescence and magnetism together with biocompatibility enables the adaptability of the present system as a nanoprobe for potential

  10. Role of Yb3+ ions on enhanced ~2.9 μm emission from Ho3+ ions in low phonon oxide glass system

    PubMed Central

    Balaji, Sathravada; Gupta, Gaurav; Biswas, Kaushik; Ghosh, Debarati; Annapurna, Kalyandurg

    2016-01-01

    The foremost limitation of an oxide based crystal or glass host to demonstrate mid- infrared emissions is its high phonon energy. It is very difficult to obtain radiative mid-infrared emissions from these hosts which normally relax non-radiatively between closely spaced energy levels of dopant rare earth ions. In this study, an intense mid-infrared emission around 2.9 μm has been perceived from Ho3+ ions in Yb3+/Ho3+ co-doped oxide based tellurite glass system. This emission intensity has increased many folds upon Yb3+: 985 nm excitation compared to direct Ho3+ excitations due to efficient excited state resonant energy transfer through Yb3+: 2F5/2 → Ho3+: 5I5 levels. The effective bandwidth (FWHM) and cross-section (σem) of measured emission at 2.9 μm are assessed to be 180 nm and 9.1 × 10−21 cm2 respectively which are comparable to other crystal/glass hosts and even better than ZBLAN fluoride glass host. Hence, this Ho3+/Yb3+ co-doped oxide glass system has immense potential for the development of solid state mid-infrared laser sources operating at 2.9 μm region. PMID:27374129

  11. Description of Panel Method Code ANTARES

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert; George, Mike (Technical Monitor)

    2000-01-01

    Panel method code ANTARES was developed to compute wall interference corrections in a rectangular wind tunnel. The code uses point doublets to represent blockage effects and line doublets to represent lifting effects of a wind tunnel model. Subsonic compressibility effects are modeled by applying the Prandtl-Glauert transformation. The closed wall, open jet, or perforated wall boundary condition may be assigned to a wall panel centroid. The tunnel walls can be represented by using up to 8000 panels. The accuracy of panel method code ANTARES was successfully investigated by comparing solutions for the closed wall and open jet boundary condition with corresponding Method of Images solutions. Fourier transform solutions of a two-dimensional wind tunnel flow field were used to check the application of the perforated wall boundary condition. Studies showed that the accuracy of panel method code ANTARES can be improved by increasing the total number of wall panels in the circumferential direction. It was also shown that the accuracy decreases with increasing free-stream Mach number of the wind tunnel flow field.

  12. Orbiter radiator panel solar focusing test

    NASA Technical Reports Server (NTRS)

    Howell, H. R.

    1982-01-01

    A test was conducted to determine the solar reflections from the Orbiter radiator panels. A one-tenth scale model of the forward and mid-forward radiator panels in the deployed position was utilized in the test. Test data was obtained to define the reflected one-sun envelope for the embossed silver/Teflon radiator coating. The effects of the double contour on the forward radiator panels were included in the test. Solar concentrations of 2 suns were measured and the one-sun envelope was found to extend approximately 86 inches above the radiator panel. A limited amount of test data was also obtained for the radiator panels with the smooth silver/Teflon coating to support the planned EVA on the Orbiter STS-5 flight. Reflected solar flux concentrations as high as 8 suns were observed with the smooth coating and the one-sun envelope was determined to extend 195 inches above the panel. It is recommended that additional testing be conducted to define the reflected solar environment beyond the one-sun boundary.

  13. Selenolate Complexes of CYP101 and the Heme-bound hHO-1/H25A Proximal Cavity Mutant

    PubMed Central

    Jiang, Yongying; Ortiz de Montellano, Paul R.

    2009-01-01

    Thiolate and selenolate complexes of CYP101 (P450cam) and the H25A proximal cavity mutant of heme-bound human heme oxygenase-1 (hHO-1) have been examined by UV-visible spectroscopy. Both thiolate and selenolate ligands bound to the heme distal side in CYP101 and gave rise to characteristic hyperporphyrin spectra. Thiolate ligands also bound to the proximal side of the heme in the cavity created by the H25A mutation in hHO-1, giving a Soret absorption similar to that of the H25C hHO-1 mutant. Selenolate ligands also bound to this cavity mutant under anaerobic conditions, but reduced the heme iron to the ferrous state as shown by formation of a ferrous-CO complex. Under aerobic conditions, the selenolate but not thiolate ligand was rapidly oxidized. These results indicate that selenocysteine-coordinated heme proteins will not be stable species in the absence of a redox potential stabilizing effect. PMID:18376820

  14. Selenolate complexes of CYP101 and the heme-bound hHO-1/H25A proximal cavity mutant.

    PubMed

    Jiang, Yongying; Ortiz de Montellano, Paul R

    2008-05-05

    Thiolate and selenolate complexes of CYP101 (P450cam) and the H25A proximal cavity mutant of heme-bound human heme oxygenase-1 (hHO-1) have been examined by UV-vis spectroscopy. Both thiolate and selenolate ligands bound to the heme distal side in CYP101 and gave rise to characteristic hyperporphyrin spectra. Thiolate ligands also bound to the proximal side of the heme in the cavity created by the H25A mutation in hHO-1, giving a Soret absorption similar to that of the H25C hHO-1 mutant. Selenolate ligands also bound to this cavity mutant under anaerobic conditions but reduced the heme iron to the ferrous state, as shown by the formation of a ferrous CO complex. Under aerobic conditions, the selenolate ligand but not the thiolate ligand was rapidly oxidized. These results indicate that selenocysteine-coordinated heme proteins will not be stable species in the absence of a redox potential stabilizing effect.

  15. Theoretical evaluation of a continues-wave Ho3+:BaY2F8 laser with mid-infrared emission

    NASA Astrophysics Data System (ADS)

    Rong, Kepeng; Cai, He; An, Guofei; Han, Juhong; Yu, Hang; Wang, Shunyan; Yu, Qiang; Wu, Peng; Zhang, Wei; Wang, Hongyuan; Wang, You

    2018-01-01

    In this paper, we build a theoretical model to study a continues-wave (CW) Ho3+:BaY2F8 laser by considering both energy transfer up-conversion (ETU) and cross relaxation (CR) processes. The influences of the pump power, reflectance of an output coupler (OC), and crystal length on the output features are systematically analyzed for an end-pumped configuration, respectively. We also investigate how the processes of ETU and CR in the energy-level system affect the output of a Ho3+:BaY2F8 laser by use of the kinetic evaluation. The simulation results show that the optical-to-optical efficiency can be promoted by adjusting the parameters such as the reflectance of an output coupler, crystal length, and pump power. It has been theoretically demonstrated that the threshold of a Ho3+:BaY2F8 laser is very high for the lasing operation in a CW mode.

  16. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E. B.

    1996-01-01

    Solar panel designs that utilize new high-efficiency solar cells and lightweight rigid panel technologies are described. The resulting designs increase the specific power (W/kg) achievable in the near-term and are well suited to meet the demands of higher performance small satellites (smallsats). Advanced solar panel designs have been developed and demonstrated on two NASA SBIR contracts at Applied Solar. The first used 19% efficient, large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells with a lightweight rigid graphite epoxy isogrid substrate configuration. A 1,445 cm(exp 2) coupon was fabricated and tested to demonstrate 60 W/kg with a high potential of achieving 80 W/kg. The second panel design used new 22% efficiency, dual junction GaInP2/GaAs/Ge solar cells combined with a lightweight aluminum core/graphite fiber mesh facesheet substrate. A 1,445 cm(exp 2) coupon was fabricated and tested to demonstrate 105 W/kg with the potential of achieving 115 W/kg. This paper will address the construction details for the GaAs/isogrid and dual-junction GaAs/carbon mesh panel configurations. These are ultimately sized to provide 75 Watts and 119 Watts respectively for smallsats or may be used as modular building blocks for larger systems. GaAs/isogrid and dual-junction GaAs/carbon mesh coupons have been fabricated and tested to successfully demonstrate critical performance parameters and results are also provided here.

  17. Aerospace safety advisory panel

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Aerospace Safety Advisory Panel (ASAP) monitored NASA's activities and provided feedback to the NASA Administrator, other NASA officials and Congress throughout the year. Particular attention was paid to the Space Shuttle, its launch processing and planned and potential safety improvements. The Panel monitored Space Shuttle processing at the Kennedy Space Center (KSC) and will continue to follow it as personnel reductions are implemented. There is particular concern that upgrades in hardware, software, and operations with the potential for significant risk reduction not be overlooked due to the extraordinary budget pressures facing the agency. The authorization of all of the Space Shuttle Main Engine (SSME) Block II components portends future Space Shuttle operations at lower risk levels and with greater margins for handling unplanned ascent events. Throughout the year, the Panel attempted to monitor the safety activities related to the Russian involvement in both space and aeronautics programs. This proved difficult as the working relationships between NASA and the Russians were still being defined as the year unfolded. NASA's concern for the unique safety problems inherent in a multi-national endeavor appears appropriate. Actions are underway or contemplated which should be capable of identifying and rectifying problem areas. The balance of this report presents 'Findings and Recommendations' (Section 2), 'Information in Support of Findings and Recommendations' (Section 3) and Appendices describing Panel membership, the NASA response to the March 1994 ASAP report, and a chronology of the panel's activities during the reporting period (Section 4).

  18. Development of fire-resistant wood structural panels

    NASA Technical Reports Server (NTRS)

    Vaughan, T. W.; Etzold, R.

    1977-01-01

    Structural panels made with Xylok 210 resin as the binder had a burn-through resistance at least equal to the structural panels made with Kerimid 500. Therefore, because of its comparative ease of handling, Xylok 210 was selected as the resin binder to provide the baseline panel for the study of a means of improving the flame-spread resistance of the structural panels. The final resin-filler system consisted of Xylok 210 binder with the addition of ammonium oxalate and ammonium phosphate to the strands of the surface layers, using 24% of each salt based upon the air-dry weight of the strands. This system resulted in a panel with a flame-spread code of about 60, a Class 2 classification. A standard phenolic based structural panel had a flame-spread greater than 200 for laboratory prepared panels. The burn-through tests indicated an average burn-through time of 588 seconds for the specimens made with the final system. This compares to an average burn-through time of 287 seconds for the standard phenolic base structural specimen. One full-size panel was made with the final system.

  19. Effect of Rare Earth Elements (Er, Ho) on Semi-Metallic Materials (ScN) in an Applied Electric Field

    NASA Technical Reports Server (NTRS)

    Kim, Hyunjung; Park, Yeonjoon; King, Glen C.; Lee, Kunik; Choi, Sang H.

    2012-01-01

    The development of materials and fabrication technology for field-controlled spectrally active optics is essential for applications such as membrane optics, filters for LIDARs, windows for sensors, telescopes, spectroscopes, cameras and flat-panel displays. The dopants of rare earth elements, in a host of optical systems, create a number of absorption and emission band structures and can easily be incorporated into many high quality crystalline and amorphous hosts. In wide band-gap semiconductors like ScN, the existing deep levels can capture or emit the mobile charges, and can be ionized with the loss or capture of the carriers which are the fundamental basis of concept for smart optic materials. The band gap shrinkage or splitting with dopants supports the possibility of this concept. In the present work, a semi-metallic material (ScN) was doped with rare earth elements (Er, Ho) and tested under an applied electric field to characterize spectral and refractive index shifts by either Stark or Zeeman Effect. These effects can be verified using the UV-Vis spectroscopy, the Hall Effect measurement and the ellipsometric spectroscopy. The optical band gaps of ScN doped with Er and doped with Ho were experimentally estimated as 2.33eV and 2.24eV ( 0.2eV) respectively. This is less than that of undoped ScN (2.5 0.2eV). The red-shifted absorption onset is a direct evidence for the decrease of band gap energy (Eg), and the broadening of valence band states is attributable to the doping cases. A decrease in refractive index with an applied field was observed as a small shift in absorption coefficient using a variable angle spectroscopic ellipsometer. In the presence of an electric field, mobile carriers are redistributed within the space charge region (SCR) to produce this electro-refractive effect. The shift in refractive index is also affected by the density and location of deep potential wells within the SCR. In addition, the microstructure change was observed by a TEM

  20. Becoming an International Scientist in South Korea: Ho Wang Lee's Research Activity about Epidemic Hemorrhagic Fever.

    PubMed

    Shin, Miyoung

    2017-04-01

    In the 1960-70s, South Korea was still in the position of a science latecomer. Although the scientific research environment in South Korea at that time was insufficient, there was a scientist who achieved outcomes that could be recognized internationally while acting in South Korea. He was Ho Wang Lee(1928~ ) who found Hantann Virus that causes epidemic hemorrhagic fever for the first time in the world. It became a clue to identify causative viruses of hemorrhagic diseases that were scattered here and there throughout the world. In addition, these outcomes put Ho Wang Lee on the global center of research into epidemic hemorrhagic fever. This paper examines how a Korean scientist who was in the periphery of virology could go into the central area of virology. Also this article shows the process through which the virus found by Ho Wang Lee was registered with the international academia and he proceeded with follow-up research based on this progress to reach the level at which he generalized epidemic hemorrhagic fever related studies throughout the world. While he was conducting the studies, experimental methods that he had never experienced encountered him as new difficulties. He tried to solve the new difficulties faced in his changed status through devices of cooperation and connection. Ho Wang Lee's growth as a researcher can be seen as well as a view of a researcher that grew from a regional level to an international level and could advance from the area of non-mainstream into the mainstream. This analytic tool is meaningful in that it can be another method of examining the growth process of scientists in South Korea or developing countries.

  1. A single-frequency Ho:YLF pulsed laser with frequency stability better than 500 kHz

    NASA Astrophysics Data System (ADS)

    Kucirek, P.; Meissner, A.; Nyga, S.; Mertin, J.; Höfer, M.; Hoffmann, H.-D.

    2017-03-01

    The spectral stability of a previously reported Ho:YLF single frequency pulsed laser oscillator emitting at 2051 nm is drastically improved by utilizing a narrow linewidth Optically Pumped Semiconductor Laser (OPSL) as a seed for the oscillator. The oscillator is pumped by a dedicated gain-switched Tm:YLF laser at 1890 nm. The ramp-and-fire method is employed for generating single frequency emission. The heterodyne technique is used to analyze the spectral properties. The laser is designed to meet a part of the specifications for future airborne or space borne LIDAR detection of CO2. Seeding with a DFB diode and with an OPSL are compared. With OPSL seeding an Allan deviation of the centroid of the spectral distribution of 38 kHz and 517 kHz over 10 seconds and 60 milliseconds of sampling time for single pulses is achieved. The spectral width is approximately 30 MHz. The oscillator emits 2 mJ pulse energy with 50 Hz pulse repetition frequency (PRF) and 20 ns pulse duration. The optical to optical efficiency of the Ho:YLF oscillator is 10 % and the beam quality is diffraction limited. To our knowledge this is the best spectral stability demonstrated to date for a Ho:YLF laser with millijoule pulse energy and nanosecond pulse duration.

  2. Cryogenic performance of slotted brazed Rene 41 honeycomb panels

    NASA Technical Reports Server (NTRS)

    Hepler, A. K.; Swegle, A. R.

    1982-01-01

    Two brazed Rene 41 honeycomb panels that would incorporate a frame element were designed, fabricated and tested. The panels were representative of the lower surface of an advanced space transportation vehicle. The first panel was a two span panel supported by a center frame and on edges parallel to it. The second panel was a two span panel supported by a center frame and on edges parallel to it. The second panel was a three span panel supported on two frames and on edges parallel to the frames. Each panel had its outer skin slotted to reduce the thermal stresses of the panel skins. The first panel was tested under simulated boost conditions that included liquid hydrogen exposure of the frame and inner skin and radiant heat to 478K on the outer skins. The first panel was tested to investigate the effect of thermal stresses in skins and core caused by the panel being restrained by a cold integral frame and to observe the effects of frost formation and possible liquid air development in and around outer skin slots.

  3. Photodetachment and UV-Vis spectral properties of Cl2rad -·nHO clusters: Extrapolation to bulk

    NASA Astrophysics Data System (ADS)

    Pathak, A. K.; Mukherjee, T.; Maity, D. K.

    2008-03-01

    Vertical detachment energy (VDE) and UV-Vis spectra of Cl2rad -·nHO clusters ( n = 1-11) are reported based on first principle electronic structure calculations. VDE of the hydrated clusters are calculated following second order Moller-Plesset perturbation (MP2) as well as coupled cluster theory with 6-311++G(d,p) set of basis function. The excess electron in these hydrated clusters is mainly localized over the solute Cl atoms. A linear relationship is obtained for VDE vs. ( n + 2.6) -1/3 and bulk VDE of Cl2rad - aqueous solution is calculated as 10.61 eV at CCSD(T) level of theory. UV-Vis spectra of these hydrated clusters are calculated applying CI with single electron (CIS) excitation procedure. Simulated UV-Vis spectra of Cl2rad -·10HO cluster is noted to be in excellent agreement with the reported spectra of Cl2rad - (aq) system, λmax for Cl2rad -·11HO system is calculated to be red shifted though.

  4. Application of groundwater sustainability indicators to the Upper Pliocene aquifer in Ho Chi Minh city, Viet Nam

    NASA Astrophysics Data System (ADS)

    Ngo, T. M.; Lee, J.; Lee, H.; Woo, N. C.

    2013-12-01

    Groundwater plays an importance role for domestic, industrial, and agricultural uses in Ho Chi Minh city, Viet Nam. This study is objected to evaluate the sustainability of groundwater by using groundwater sustainability indicators (GWSIs) defined by UNESCO/IAEA/IAH Working Group on Groundwater Indicators at aquifer scale (the Upper Pliocene aquifer). There are four main indicators selected and one new indicator designed for the particular characteristic of Ho Chi Minh city which is under influence of by saline-water intrusion. The results indicated groundwater of the Upper Pliocene aquifer, the main groundwater supply source, is generally in the unsustainable state. The abstraction of groundwater, which was much greater than its capability, is probably causing the serious state of annual groundwater depletion and saline-water intrusion. The GWSIs, which expressed in such a simple way but scientifically-based and policy-relevant, proved its usefulness in evaluating the sustainability of groundwater at the aquifer scale in Ho Chi Minh city, and subsequently should be incorporated in water resource management practices.

  5. ETV Report:Siemens Model H-4XE-HO Open Channel UV System

    EPA Science Inventory

    Verification testing of the Siemens Barrier Sunligt H-4XE-HO UV System was completed at the UV Validation and Research Center of New York (UV Center), located in Johnstown, NY. The H-4XE System utilizes 16 high-output, low-pressure lamps oriented horizontally and parallel to the...

  6. Notice of release of a high fiber sugarcane variety Ho 02-113

    USDA-ARS?s Scientific Manuscript database

    The United States Department of Agriculture’s Agricultural Research Service, Sugarcane Research Unit (SRU); the Louisiana Agricultural Experiment Station of the LSU Agricultural Center; and the American Sugar Cane League of the U.S.A, Inc., announce the release of a new high-fiber variety, Ho 02-113...

  7. Report of Industry Panel Group

    NASA Technical Reports Server (NTRS)

    Gallimore, Simon; Gier, Jochen; Heitland, Greg; Povinelli, Louis; Sharma, Om; VandeWall, Allen

    2006-01-01

    A final report is presented from the industry panel group. The contents include: 1) General comments; 2) Positive progress since Minnowbrook IV; 3) Industry panel outcome; 4) Prioritized turbine projects; 5) Prioritized compressor projects; and 6) Miscellaneous.

  8. Method for producing micro heat panels

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J. (Inventor); Peterson, George P. (Inventor); Rummler, Donald R. (Inventor)

    1997-01-01

    Flat or curved micro heat pipe panels are fabricated by arranging essentially parallel filaments in the shape of the desired panel. The configuration of the filaments corresponds to the desired configuration of the tubes that will constitute the heat pipes. A thermally conductive material is then deposited on and around the filaments to fill in the desired shape of the panel. The filaments are then removed, leaving tubular passageways of the desired configuration and surface texture in the material. The tubes are then filled with a working fluid and sealed. Composite micro heat pipe laminates are formed by layering individual micro heat pipe panels and bonding them to each other to form a single structure. The layering sequence of the micro heat pipe panels can be tailored to transport heat preferentially in specific directions as desired for a particular application.

  9. Aerospace Safety Advisory Panel

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report covers the activities of the Aerospace Safety Advisory Panel (ASAP) for calendar year 1998-a year of sharp contrasts and significant successes at NASA. The year opened with the announcement of large workforce cutbacks. The slip in the schedule for launching the International Space Station (ISS) created a five-month hiatus in Space Shuttle launches. This slack period ended with the successful and highly publicized launch of the STS-95 mission. As the year closed, ISS assembly began with the successful orbiting and joining of the Functional Cargo Block (FGB), Zarya, from Russia and the Unity Node from the United States. Throughout the year, the Panel maintained its scrutiny of NASA's safety processes. Of particular interest were the potential effects on safety of workforce reductions and the continued transition of functions to the Space Flight Operations Contractor. Attention was also given to the risk management plans of the Aero-Space Technology programs, including the X-33, X-34, and X-38. Overall, the Panel concluded that safety is well served for the present. The picture is not as clear for the future. Cutbacks have limited the depth of talent available. In many cases, technical specialties are 'one deep.' The extended hiring freeze has resulted in an older workforce that will inevitably suffer significant departures from retirements in the near future. The resulting 'brain drain' could represent a future safety risk unless appropriate succession planning is started expeditiously. This and other topics are covered in the section addressing workforce. The major NASA programs are also limited in their ability to plan property for the future. This is of particular concern for the Space Shuttle and ISS because these programs are scheduled to operate well into the next century. In the case of the Space Shuttle, beneficial and mandatory safety and operational upgrades are being delayed because of a lack of sufficient present funding. Likewise, the ISS has

  10. The TallyHo polygenic mouse model of diabetes: implications in wound healing.

    PubMed

    Buck, Donald W; Jin, Da P; Geringer, Matthew; Hong, Seok Jong; Galiano, Robert D; Mustoe, Thomas A

    2011-11-01

    Impairments in wound healing represent a significant source of morbidity and mortality in patients with diabetes. To help uncover the derangements associated with diabetic wound healing, murine animal models have been extensively used. In this article, the authors present results, and the accompanying wound healing implications, from experiments across three validated wound healing models using a newer polygenic strain of diabetes. The authors investigated the wound healing impairments of the TallyHo/JnJ diabetic mouse strain, using three validated wound healing models: an incisional model, a splinted excisional model, and a cutaneous ischemia-reperfusion injury model. Appropriate control strain mice were used for comparison. Wounds were analyzed using gross, histologic, and molecular techniques. TallyHo mice displayed deficits across all three wound healing models. There was a reduced resistance/response to oxidative stress and a global decrease in the initial inflammatory response to healing. In addition, there was a global decrease in the stimulus for angiogenesis and collagen formation, ultimately leading to reduced reepithelialization, granulation tissue formation, wound contraction, and wound tensile strength. Gross and histologic findings were corroborated with molecular data, which revealed a significant down-regulation of important cytokines, including vascular endothelial growth factor, neutrophilic attractant protein-2, monocyte chemoattractant protien-1, heme oxygenase-1, interleukin-1β, and interleukin-6, when normalized to the control strain (p<0.05). The TallyHo polygenic mouse model of diabetes demonstrates predictable and clinically relevant wound healing impairments that offer important implications into the derangements of diabetic wound healing observed clinically. Therapeutics targeting these specific derangements could provide improvements in the care of diabetic wounds.

  11. [HoLEP learning curve: Toward a standardised formation and a team strategy].

    PubMed

    Baron, M; Nouhaud, F-X; Delcourt, C; Grise, P; Pfister, C; Cornu, J-N; Sibert, L

    2016-09-01

    Holmium laser enucleation of prostate (HoLEP) is renowned for the difficulty of its learning curve. Our aim was to evaluate the interest of a three-step tutorial in the HoLEP learning curve, in a university center. It is a retrospective, monocentric study of the 82 first procedures done consecutively by the same operator with a proctoring in early experience and after 40 procedures. For all patients were noted: enucleation efficiency (g/min), morcellation efficiency (g/min), percentage of enucleated tissue (enucleated tissue/adenome weigth evaluated by ultrasonography. g/g), perioperative morbidity (Clavien), length of hospital stay, length of urinary drainage, functional outcomes at short and middle term (Qmax, post-void residual volume [PVR], QOL scores and IPSS at 3 and 6months). Enucleation and morcellation efficiency were significantly higher after the second proctoring (0.87 vs 0.44g/min; P<0.0001 and 4.2 vs 3.37g/min, P=0.038, respectively) so as the prostatic volume (43.5 vs 68.1mL, P=0.0001). Percentage of enucleated tissue was higher in the second group, however, the difference was not significant (69.5% vs 80.4%, P=0.03). Per- and postoperative complications, hospital length of stay, urinary drainage length and functional results at 3 and 6months were not significantly different. The learning curve did not interfere with functional results. The second proctoring was essential to us in order to grasp the technique. These data underlined the necessity of a pedagogic reflexion in order to built a standardized formation technique to the HoLEP. 4. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  12. Multicolor upconversion emission from Tm3++Ho3++Yb3+ codoped tellurite glass on NIR excitations

    NASA Astrophysics Data System (ADS)

    Giri, N. K.; Rai, D. K.; Rai, S. B.

    2008-06-01

    Multicolor emission has been produced using 798 nm and 980 nm laser excitation in a Tm3++Ho3++Yb3+ codoped tellurite based glass. This glass generates simultaneously red, green and blue (RGB) emission on 798 nm excitation. Multicolor emission thus obtained was tuned to white luminescence by adjusting the Ho3+ ion concentration. There is a close match between the calculated color coordinate for the white luminescence obtained here and the point of equal energy which represents white in the 1931 CIE chromaticity diagram. The 980 nm excitation of the same sample on the other hand gives intense green and red emission and the glass appears greenish.

  13. PRSEUS Panel Fabrication Final Report

    NASA Technical Reports Server (NTRS)

    Linton, Kim A.; Velicki, Alexander; Hoffman, Krishna; Thrash, Patrick; Pickell, Robert; Turley, Robert

    2014-01-01

    NASA and the Boeing Company have been working together under the Environmentally Responsible Aviation Project to develop stitched unitized structure for reduced weight, reduced fuel burn and reduced pollutants in the next generation of commercial aircraft. The structural concept being evaluated is PRSEUS (Pultruded Rod Stitched Efficient Unitized Structure). In the PRSEUS concept, dry carbon fabric, pultruded carbon rods, and foam are stitched together into large preforms. Then these preforms are infused with an epoxy resin into large panels in an out-of-autoclave process. These panels have stiffeners in the length-wise and width-wise directions but contain no fasteners because all stiffeners are stitched to the panel skin. This document contains a description of the fabrication of panels for use in the 30-foot-long Multi-Bay Box test article to be evaluated at NASA LaRC.

  14. Structural and thermal testing of lightweight reflector panels

    NASA Technical Reports Server (NTRS)

    Mcgregor, J.; Helms, R.; Hill, T.

    1992-01-01

    The paper describes the test facility developed for testing large lightweight reflective panels with very accurate and stable surfaces, such as the mirror panels of composite construction developed for the NASA's Precision Segmented Reflector (PSR). Special attention is given to the panel construction and the special problems posed by the characteristics of these panels; the design of the Optical/Thermal Vacuum test facility for structural and thermal testing, developed at the U.S. AFPL; and the testing procedure. The results of the PSR panel test program to date are presented. The test data showed that the analytical approaches used for the panel design and for the prediction of the on-orbit panel behavior were adequate.

  15. Study of morphology and magnetic properties of the HoNi{sub 3} crystalline and ball-milled compound

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bajorek, Anna, E-mail: anna.bajorek@us.edu.pl; Silesian Center for Education and Interdisciplinary Research, University of Silesia, 75 Pułku Piechoty 1A, 41-500 Chorzów; Skornia, Paweł

    2015-03-15

    The morphology and magnetic properties of the HoNi{sub 3} crystalline and ball-milled intermetallic compounds are presented. The polycrystalline HoNi{sub 3} bulk compound crystallizes in the rhombohedral PuNi{sub 3} — type of crystal structure and indicates ferrimagnetic arrangement with the Curie temperature of T{sub C} = 57 ± 2 K, the helimagnetic temperature T{sub h} = 23 ± 2 K with the total saturation magnetic moment of 6.84 μ{sub B}/f.u. at 2 K. The use of the ball-milling method leads to the formation of HoNi{sub 3} nanoflakes with typical thickness of less than 100 nm prone to agglomeration upon milling. Themore » increase of grinding duration leads to the reduction in crystallite size, which was confirmed by various complementary microscopical and diffraction studies. Moreover, the increase in milling duration results in the emergence of the relatively small coercivity (H{sub C}), remanence (M{sub r}) and a variation of the saturation magnetization (M{sub S}). - Graphical abstract: Display Omitted - Highlights: • The ball-milling method exhibits significant potential for producing RT{sub 3} nanopowders. • The AFM method was used for the first time in analysis of R–T nanoflakes morphology. • HoNi{sub 3} compound forms polycrystalline and textured nanoflakes evolving upon milling. • The decrease in crystallite size via grinding is confirmed by XRD, TEM and AFM. • The magnetic parameters were sensitive to the extension of pulverization b.« less

  16. Epigallocatechin-3-gallate (EGCG) protects skin cells from ionizing radiation via heme oxygenase-1 (HO-1) overexpression.

    PubMed

    Zhu, Wei; Xu, Jing; Ge, Yangyang; Cao, Han; Ge, Xin; Luo, Judong; Xue, Jiao; Yang, Hongying; Zhang, Shuyu; Cao, Jianping

    2014-11-01

    Epigallocatechin-3-gallate (EGCG), the major polyphenolic constituent of green tea, is a potent antioxidant and free radical scavenger that may have therapeutic applications for the treatment of many disorders. Radiation therapy is widely used for the treatment of various types of cancers; however, radiation-induced skin injury remains a serious concern. EGCG has not yet been reported as protecting skin cells against ionizing radiation. In the present study, we investigated whether EGCG confers cytoprotection against ionizing radiation. We found that, compared with the control, pretreatment with EGCG significantly enhanced the viability of human skin cells that were irradiated with X-rays, and decreased apoptosis induced by X-ray irradiation. Mito-Tracker assay showed that EGCG suppressed the damage to mitochondria induced by ionizing radiation via upregulation of SOD2. Reactive oxygen species (ROS) in HaCaT cells were significantly reduced when pretreated with EGCG before irradiation. Radiation-induced γH2AX foci, which are representative of DNA double-strand breaks, were decreased by pretreatment with EGCG. Furthermore, EGCG induced the expression of the cytoprotective molecule heme oxygenase-1 (HO-1) in a dose-dependent manner via transcriptional activation. HO-1 knockdown or treatment with the HO-1 inhibitor tin protoporphyrin (SnPPIX) reversed the protective role of EGCG, indicating an important role for HO-1. These results suggest that EGCG offers a new strategy for protecting skin against ionizing radiation. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  17. Structure, upconversion photoluminescence, and dielectric properties of Ho{sup 3+}- and Yb{sup 3+}-codoped tetragonal tungsten bronze Sr{sub 4}La{sub 2}Ti{sub 4}Nb{sub 6}O{sub 30}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wei, T., E-mail: weitong.nju@gmail.com; Li, C.P.; Zhou, Q.J.

    2015-04-15

    Highlights: • TTB-type SLTN: Ho-Ybx with space group P4/mbm was determined. • UC photoluminescence of SLTN: Ho-Ybx ceramics was first reported. • Bright UC green emission was observed at room temperature. • Two-photon energy transfer process was confirmed for the UC processes. • Temperature stability of dielectric permittivity was improved for SLTN: Ho-Ybx. - Abstract: Ho{sup 3+}- and Yb{sup 3+}-codoped Sr{sub 4}La{sub 2}Ti{sub 4}Nb{sub 6}O{sub 30} (Sr{sub 4}La{sub 1.94–x}Ho{sub 0.06}Yb{sub x}Ti{sub 4}Nb{sub 6}O{sub 30}, abbreviated as SLTN: Ho-Ybx) ceramics have been synthesized, and their structural, up-conversion (UC) photoluminescence, and dielectric properties have been carefully investigated. Through Rietveld structural refinement, SLTN:more » Ho-Ybx samples are determined as single tetragonal tungsten bronze (TTB) phase with space group P4/mbm in which larger Sr{sup 2+} ions fill the A{sub 2}-sites, relative smaller La{sup 3+}, Ho{sup 3+}, and Yb{sup 3+} ions occupy the A{sub 1}-sites, while Ti{sup 4+} and Nb{sup 4+} ions fill the B-sites. Under 980 nm near infrared (NIR) excitation, bright UC green emission, relatively weak red and near-infrared (NIR) emissions, originating from {sup 5}F{sub 4}/{sup 5}S{sub 2} → {sup 5}I{sub 8}, {sup 5}F{sub 5} → {sup 5}I{sub 8}, and {sup 5}F{sub 4}/{sup 5}S{sub 2} → {sup 5}I{sub 7} transitions of Ho{sup 3+} ions, are confirmed for SLTN: Ho-Ybx. Two-photon energy transfer process is proved through pumping laser power dependence of emission intensity measurement. Furthermore, the influence of Ho{sup 3+}- and Yb{sup 3+}- ions on the dielectric properties of SLTN: Ho-Ybx is also investigated and the temperature stability of dielectric permittivity is improved.« less

  18. Compact intra-cavity pumped low-threshold passively Q-switched Ho:Sc2SiO5 laser by a LD-pumped Tm:YAP laser at room temperature

    NASA Astrophysics Data System (ADS)

    Yang, Xiao-tao; Xie, Wen-qiang; Liu, Long; Li, Lin-jun

    2017-08-01

    A compact intra-cavity pumped low-threshold passively Q-switched (PQS) Ho:Sc2SiO5 (Ho:SSO) laser is reported for the first time. The Tm:YAlO3 (Tm:YAP) crystal and the Ho:SSO crystal are placed in the same laser cavity. A laser diode with a central wavelength of 793 nm is used to realize the output of the Ho:SSO laser. Both the continuous wave (CW) and PQS operation are investigated. A Cr2+:ZnSe is used as the saturable absorber in the PQS Ho:SSO laser. For the CW mode, the laser threshold is only 750 mW, which is 980 mW in the PQS mode. A maximum pulse energy of 699 µJ is primarily obtained, corresponding to the pulse width of 96 ns. The maximum repetition frequency is 1.46 kHz. The maximum pulse peak power can be calculated to be 7.28 kW. The beam quality factor M 2 is calculated to be 1.4 with the maximum output power.

  19. Magnetostructural phase transitions and magnetocaloric effect in Tb-Dy-Ho-Co-Al alloys with a Laves phase structure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tereshina, I. S., E-mail: irina-tereshina@mail.ru; Baikov Institute of Metallurgy and Material Sciences, Russian Academy of Sciences, Moscow 119991; International Laboratory of High Magnetic Fields and Low Temperatures, Wroclaw 53-421

    2016-07-07

    The influence of simultaneous substitution within the rare earth (R) and Co sublattices on the structural, magnetic, and magnetocaloric properties of the Laves phase RCo{sub 2}-type compounds is studied. Main attention is devoted to the studies of the magnetostructural phase transitions and the transition types with respect to the alloy composition. Multicomponent alloys Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} and Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 1.75}Al{sub 0.25} were prepared with the use of high purity metals. Majority of the Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} alloys exhibit magnetic transitions of the first-order type and a large magnetocaloric effect. The substitutionmore » of Al for Co in Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} increases the Curie temperature (T{sub C}) but changes the transition type from first-to the second-order. The discussion of the physical mechanisms behind the observed phenomena is given on the basis of the first principles electronic-structure calculations taking into account both the atomic disorder and the magnetic disorder effects at finite temperatures. The advantage of Al-containing materials is that sufficiently high magnetocaloric effect values are preserved at T > T{sub C}.« less

  20. Subcritical water-hydrolyzed fish collagen ameliorates survival of endotoxemic mice by inhibiting HMGB1 release in a HO-1-dependent manner.

    PubMed

    Ahn, Min Young; Hwang, Jung Seok; Ham, Sun Ah; Hur, Jinwoo; Jo, Yeonji; Lee, SangYoon; Choi, Mi-Jung; Han, Sung Gu; Seo, Han Geuk

    2017-09-01

    To investigate potential mechanisms underlying the bioactivity of hydrolyzed fish collagen, we examined the anti-inflammatory actions of subcritical water-hydrolyzed fish collagen (SWFC) in lipopolysaccharide (LPS)-triggered inflammation and endotoxemia. SWFC markedly inhibited LPS-stimulated release of high mobility group box 1 (HMGB1) in murine RAW264.7 macrophages, along with decreased cytosolic translocation of HMGB1. Both the protein and mRNA levels of heme oxygenase-1 (HO-1) were significantly upregulated in SWFC-treated RAW 264.7 cells in an Nrf2-dependent manner. In line with these effects of SWFC, both HO-1 siRNA and ZnPPIX (zinc protoporphyrin IX) actually attenuated the effects of SWFC on HMGB1 release stimulated by LPS, indicating a possible mechanism by which SWFC modulates HMGB1 release through HO-1 signaling. Notably, administration of SWFC improved the survival rates of LPS-injected endotoxemic mice, in which the serum level of HMGB1 was significantly reduced. Taken together, these results indicate that the anti-inflammatory activities of SWFC are achieved by inhibiting HMGB1 release induced by LPS in a HO-1-sensitive manner. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  1. 5-Aminolevulinic acid with sodium ferrous citrate induces autophagy and protects cardiomyocytes from hypoxia-induced cellular injury through MAPK-Nrf-2-HO-1 signaling cascade

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Mingyi; Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou; Department of Pediatrics, The Third Xiangya Hospital, Central South University, Changsha

    Background: Hypoxia causes cardiac disease via oxidative stress and mitochondrial dysfunction. 5-Aminolevulinic acid in combination with sodium ferrous citrate (ALA/SFC) has been shown to up-regulate heme oxygenase-1 (HO-1) and decrease macrophage infiltration and renal cell apoptosis in renal ischemia injury mice. However, its underlying mechanism remains largely unknown. The aim of this study was to investigate whether ALA/SFC could protect cardiomyocytes from hypoxia-induced apoptosis by autophagy via HO-1 signaling. Materials & methods: Murine atrial cardiomyocyte HL-1 cells were pretreated with ALA/SFC and then exposed to hypoxia. Results: ALA/SFC pretreatment significantly attenuated hypoxia-induced cardiomyocyte apoptosis, reactive oxygen species production, and mitochondrial injury,more » while it increased cell viability and autophagy levels. HO-1 expression by ALA/SFC was associated with up-regulation and nuclear translocation of Nrf-2, whereas Nrf-2 siRNA dramatically reduced HO-1 expression. ERK1/2, p38, and SAPK/JNK pathways were activated by ALA/SFC and their specific inhibitors significantly reduced ALA/SFC-mediated HO-1 upregulation. Silencing of either Nrf-2 or HO-1and LY294002, inhibitor of autophagy, abolished the protective ability of ALA/AFC against hypoxia-induced injury and reduced ALA/SFC-induced autophagy. Conclusion: Taken together, our data suggest that ALA/SFC induces autophagy via activation of MAPK/Nrf-2/HO-1 signaling pathway to protect cardiomyocytes from hypoxia-induced apoptosis. - Highlights: • ALA/SFC attenuates hypoxia-induced cardiomyocyte apoptosis, reactive oxygen species production, and mitochondrial injury. • ALA/SFC increases the heme oxygenase-1 expression via Nrf-2 and ERK1/2, p38, and SAPK/JNK pathways. • ALA/SFC induces autophagy and inhibition of autophagy prevent ALA/SFC-mediated suppression of hypoxia-induced injury.« less

  2. Active magnetic compensation composed of shielding panels.

    PubMed

    Kato, K; Yamazaki, K; Sato, T; Haga, A; Okitsu, T; Muramatsu, K; Ueda, T; Kobayashi, K; Yoshizawa, M

    2004-11-30

    Magnetically shielded rooms (MSRs) with materials of high permeability and active shield systems have been used to shield magnetic noise for biomagnetic measurements up to now. However, these techniques have various disadvantages. Therefore, we have developed a new shielding system composed of shielding panels using an active compensation technique. In this study, we evaluated the shielding performance of several unit panels attached together. Numerical and experimental approaches indicated that the shielding factor of a cubic model composed of 24 panels was 17 for uniform fields, and 7 for disturbances due to car movement. Furthermore, the compensation space is larger than that of an ordinary active system using large coils rather than panels. Moreover, the new active compensation system has the important advantage that panels of any shape can be assembled for occasional use because the unit panels are small and light.

  3. Multiplex real-time RT-PCR assay for bovine viral diarrhea virus type 1, type 2 and HoBi-like pestivirus.

    PubMed

    Mari, Viviana; Losurdo, Michele; Lucente, Maria Stella; Lorusso, Eleonora; Elia, Gabriella; Martella, Vito; Patruno, Giovanni; Buonavoglia, Domenico; Decaro, Nicola

    2016-03-01

    HoBi-like pestiviruses are emerging pestiviruses that infect cattle causing clinical forms overlapping to those induced by bovine viral diarrhea virus (BVDV) 1 and 2. As a consequence of their widespread distribution reported in recent years, molecular tools for rapid discrimination among pestiviruses infecting cattle are needed. The aim of the present study was to develop a multiplex real-time RT-PCR assay, based on the TaqMan technology, for the rapid and unambiguous characterisation of all bovine pestiviruses, including the emerging HoBi-like strains. The assay was found to be sensitive, specific and repeatable, ensuring detection of as few as 10(0)-10(1) viral RNA copies. No cross-reactions between different pestiviral species were observed even in samples artificially contaminated with more than one pestivirus. Analysis of field samples tested positive for BVDV-1, BVDV-2 or HoBi-like virus by a nested PCR protocol revealed that the developed TaqMan assay had equal or higher sensitivity and was able to discriminate correctly the viral species in all tested samples, whereas a real-time RT-PCR assay previously developed for HoBi-like pestivirus detection showed cross-reactivity with few high-titre BVDV-2 samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Hexagon solar power panel

    NASA Technical Reports Server (NTRS)

    Rubin, I. (Inventor)

    1978-01-01

    A solar energy panel support is described upon which silicon cells are arrayed. The cells are wafer thin and of two geometrical types, both of the same area and electrical rating, namely hexagon cells and hourglass cells. The hourglass cells are composites of half hexagons. A near perfect nesting relationship of the cells achieves a high density packing whereby optimum energy production per panel area is achieved.

  5. Hexagon solar power panel

    DOEpatents

    Rubin, Irwin

    1978-01-01

    A solar energy panel comprises a support upon which silicon cells are arrayed. The cells are wafer thin and of two geometrical types, both of the same area and electrical rating, namely hexagon cells and hourglass cells. The hourglass cells are composites of half hexagons. A near perfect nesting relationship of the cells achieves a high density packing whereby optimum energy production per panel area is achieved.

  6. Installation of prestressed panel subdecks.

    DOT National Transportation Integrated Search

    1977-01-01

    This report is concerned with the field installation of prestressed panel subdecks on the Rte 220 bridges over relocated 23rd St. in the city of Roanoke. These were the first bridges to be constructed in Virginia utilizing the precast subdeck panel c...

  7. Sam Ho on health system quality and population medicine. Interview by Nancy Houyoux.

    PubMed

    Ho, Sam

    2003-01-01

    As PacifiCare Health Systems' senior vice president and chief medical officer, Dr. Sam Ho is responsible for developing and implementing strategies and programs to improve the quality and cost-effectiveness of healthcare services throughout the company. Dr. Ho is responsible for all initiatives related to quality assessment and improvement, medical management, disease management, informatics, report cards, clinical product development, e-health, and healthcare liaison with public policy, government affairs, industry relations, media relations, provider network management, and sales and marketing. Since joining PacifiCare in its California MCO in October 1994, he has spearheaded companywide quality initiatives and improvement in population health outcomes, and developed the QUALITY INDEX profile of medical groups, a consumer-focused report card of provider performance. He also led efforts to achieve systemwide accreditation by the National Committee for Quality Assurance in all markets and Health Plan Employer Data and Information Set (HEDIS) score improvements. Previously he served as deputy director of health, medical director, and county health officer for the San Francisco Department of Public Health. He has held faculty appointments at the Schools of both Medicine and Nursing at the University of California, San Francisco. The Honolulu native received his BA in sociology from Northwestern University in 1972 with Phi Beta Kappa honors and his MD from Tufts University School of Medicine in 1976. Dr. Ho completed his residency in family practice at the University of California, San Francisco, and has since maintained board certification with the American Board of Family Practice.

  8. 76 FR 32957 - Hydrographic Services Review Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ... Review Panel AGENCY: National Ocean Service, National Oceanic and Atmospheric Administration (NOAA), Department of Commerce. ACTION: Notice of membership solicitation for Hydrographic Services Review Panel...), to solicit nominations for membership on the Hydrographic Services Review Panel (HSRP). The HSRP, a...

  9. 77 FR 76001 - Hydrographic Services Review Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-26

    ... Review Panel AGENCY: National Ocean Service, National Oceanic and Atmospheric Administration (NOAA), Department of Commerce. ACTION: Notice of membership solicitation for Hydrographic Services Review Panel... Review Panel (HSRP). The HSRP, a Federal advisory committee, advises the Administrator on matters related...

  10. 75 FR 20809 - Hydrographic Services Review Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... Review Panel AGENCY: National Ocean Service, National Oceanic and Atmospheric Administration (NOAA), Department of Commerce. ACTION: Notice of Additional Membership Solicitation for Hydrographic Services Review... applications for membership on the Hydrographic Services Review Panel (the Panel), a Federal advisory committee...

  11. Mode-locked Tm,Ho:KLu(WO(4))(2) laser at 2060 nm using InGaSb-based SESAMs.

    PubMed

    Aleksandrov, Veselin; Gluth, Alexander; Petrov, Valentin; Buchvarov, Ivan; Steinmeyer, Günter; Paajaste, Jonna; Suomalainen, Soile; Härkönen, Antti; Guina, Mircea; Mateos, Xavier; Díaz, Francesc; Griebner, Uwe

    2015-02-23

    Passive mode-locking of a Tm,Ho:KLu(WO(4))(2) laser operating at 2060 nm using different designs of InGaAsSb quantum-well based semiconductor saturable absorber mirrors (SESAMs) is demonstrated. The self-starting mode-locked laser delivers pulse durations between 4 and 8 ps at a repetition rate of 93 MHz with maximum average output power of 155 mW. Mode-locking performance of a Tm,Ho:KLu(WO(4))(2) laser is compared for usage of a SESAM to a single-walled carbon nanotube saturable absorber.

  12. Use of precast concrete deck panels : summary of research panel types I, II, and III.

    DOT National Transportation Integrated Search

    1999-08-01

    The objective of this research was to investigate the feasibility of using precast concrete deck panels in place of traditional formwork for AASHTO girder type bridges. The precast deck panels span between girders, support the weight of a topping sla...

  13. Oven wall panel construction

    DOEpatents

    Ellison, Kenneth; Whike, Alan S.

    1980-04-22

    An oven roof or wall is formed from modular panels, each of which comprises an inner fabric and an outer fabric. Each such fabric is formed with an angle iron framework and somewhat resilient tie-bars or welded at their ends to flanges of the angle irons to maintain the inner and outer frameworks in spaced disposition while minimizing heat transfer by conduction and permitting some degree of relative movement on expansion and contraction of the module components. Suitable thermal insulation is provided within the module. Panels or skins are secured to the fabric frameworks and each such skin is secured to a framework and projects laterally so as slidingly to overlie the adjacent frame member of an adjacent panel in turn to permit relative movement during expansion and contraction.

  14. Efficient Operation of Conductively Cooled Ho:Tm:LuLiF Laser Oscillator/Amplifier

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Bai, Yingxin; Trieu, Bo; Petros, M.; Petzar, Paul; Lee, Hyung; Singh, U.

    2008-01-01

    A conductively-cooled Ho:Tm:LuLiF laser oscillator generates 1.6J normal mode pulses at 10Hz with optical to optical efficiency of 20%. When the laser head module is used as the amplifier, the double-pass small-signal amplification excesses 25.

  15. Damage tolerance of woven graphite-epoxy buffer strip panels

    NASA Technical Reports Server (NTRS)

    Kennedy, John M.

    1990-01-01

    Graphite-epoxy panels with S glass buffer strips were tested in tension and shear to measure their residual strengths with crack-like damage. The buffer strips were regularly spaced narrow strips of continuous S glass. Panels were made with a uniweave graphite cloth where the S glass buffer material was woven directly into the cloth. Panels were made with different width and thickness buffer strips. The panels were loaded to failure while remote strain, strain at the end of the slit, and crack opening displacement were monitoring. The notched region and nearby buffer strips were radiographed periodically to reveal crack growth and damage. Except for panels with short slits, the buffer strips arrested the propagating crack. The strength (or failing strain) of the panels was significantly higher than the strength of all-graphite panels with the same length slit. Panels with wide, thick buffer strips were stronger than panels with thin, narrow buffer strips. A shear-lag model predicted the failing strength of tension panels with wide buffer strips accurately, but over-estimated the strength of the shear panels and the tension panels with narrow buffer strips.

  16. Thin film photovoltaic panel and method

    DOEpatents

    Ackerman, Bruce; Albright, Scot P.; Jordan, John F.

    1991-06-11

    A thin film photovoltaic panel includes a backcap for protecting the active components of the photovoltaic cells from adverse environmental elements. A spacing between the backcap and a top electrode layer is preferably filled with a desiccant to further reduce water vapor contamination of the environment surrounding the photovoltaic cells. The contamination of the spacing between the backcap and the cells may be further reduced by passing a selected gas through the spacing subsequent to sealing the backcap to the base of the photovoltaic panels, and once purged this spacing may be filled with an inert gas. The techniques of the present invention are preferably applied to thin film photovoltaic panels each formed from a plurality of photovoltaic cells arranged on a vitreous substrate. The stability of photovoltaic conversion efficiency remains relatively high during the life of the photovoltaic panel, and the cost of manufacturing highly efficient panels with such improved stability is significantly reduced.

  17. Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1

    PubMed Central

    Abdelbaset-Ismail, A; Borkowska-Rzeszotek, S; Kubis, E; Bujko, K; Brzeźniakiewicz-Janus, K; Bolkun, L; Kloczko, J; Moniuszko, M; Basak, G W; Wiktor-Jedrzejczak, W; Ratajczak, M Z

    2017-01-01

    As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK–HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated. PMID:27451975

  18. Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1.

    PubMed

    Abdelbaset-Ismail, A; Borkowska-Rzeszotek, S; Kubis, E; Bujko, K; Brzeźniakiewicz-Janus, K; Bolkun, L; Kloczko, J; Moniuszko, M; Basak, G W; Wiktor-Jedrzejczak, W; Ratajczak, M Z

    2017-02-01

    As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK-HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated.

  19. Balancing structural distortions via competing 4f and itinerant interactions: A case of polymorphism in magnetocaloric HoCo 2

    DOE PAGES

    Mudryk, Y.; Paudyal, D.; Pathak, A. K.; ...

    2016-04-13

    The nature of multiple magnetostructural transformations in HoCo 2 has been studied by employing magnetic and specific heat measurements, temperature and magnetic field dependent X-ray powder diffraction, and first-principles calculations. Unexpected increase of magnetization observed below the spin-reorientation temperature (T SR) suggests that the low-temperature transition involves a reduction of Co moment. First principles calculations confirm that the paramagnetic cubic to ferrimagnetic tetragonal transformation at T C is assisted by itinerant electron metamagnetism, and that the reduction of Co moment in HoCo 2 occurs in parallel with the ferrimagnetic tetragonal to the nearly ferromagnetic orthorhombic transformation at T SRvia themore » rearrangement of both 3d states of Co and 5d states of Ho. The ac magnetic susceptibility measurements show significant magnetic frustration below T C. Furthermore, in contrast to earlier reports neither ac nor dc magnetic susceptibilities show anomalies in the paramagnetic region obeying the Curie–Weiss law.« less

  20. Quantum probe of Hořava-Lifshitz gravity

    NASA Astrophysics Data System (ADS)

    Gurtug, O.; Mangut, M.

    2018-04-01

    Particle probe analysis of the Kehagias-Sfetsos black hole spacetime of Hořava-Lifshitz gravity is extended to wave probe analysis within the framework of quantum mechanics. The time-like naked singularity that develops when ωM2 < 1/2 is probed with quantum fields obeying Klein-Gordon and Chandrasekhar-Dirac equations. The quantum field probe of the naked singularity has revealed that both the spatial part of the wave and the Hamiltonian operators of Klein-Gordon and Chandrasekhar-Dirac equations are essentially self-adjoint, and thus, the naked singularity in the Kehagias-Sfetsos spacetime becomes quantum mechanically non-singular.

  1. Numerical simulation of wind loads on solar panels

    NASA Astrophysics Data System (ADS)

    Su, Kao-Chun; Chung, Kung-Ming; Hsu, Shu-Tsung

    2018-05-01

    Solar panels mounted on the roof of a building or ground are often vulnerable to strong wind loads. This study aims to investigate wind loads on solar panels using computational fluid dynamic (CFD). The results show good agreement with wind tunnel data, e.g. the streamwise distribution of mean surface pressure coefficient of a solar panel. Wind uplift for solar panels with four aspect ratios is evaluated. The effect of inclined angle and clearance (or height) of a solar panel is addressed. It is found that wind uplift of a solar panel increases when there is an increase in inclined angle and the clearance above ground shows an opposite effect.

  2. Integrally rigidized acoustic interior spacecraft panel

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A sandwich panel concept is described which utilizes a monolithic I-beam design as the core. The core and skins are integrally bonded with thermosetting resin into a homogeneous structure. In addition to possessing a high strength to weight ratio, the panel resists combustion, delamination, aging due to fatigue, localized stresses, and exhibits good acoustic properties. Since the panel concept has definite potential as a high flame retardant and low smoke emission panel with excellent structural integrity, aerospace materials were used to optimize the construction for highly demanding space shuttle applications. The specific materials of construction were chosen for low flammability and off-gassing properties as well as for strength, light weight, and sound dampening.

  3. Sticking of HO2 on fatty acids aggregates

    NASA Astrophysics Data System (ADS)

    Vardanega, Delphine; Briquez, Stéphane; Duflot, Denis; Monnerville, Maurice; Toubin, Céline

    2015-04-01

    Models of atmospheric chemistry are widely used to perform projections of future changes in the chemical composition of the global troposphere, including changes in climate related greenhouse gases and aerosol particles. However, large uncertainties are still associated with the chemistry implemented in these models, which in turn can lead to inaccurate long-term predictions. The proposed work seeks to improve our understanding of the oxidative capacity of the atmosphere, which drives the lifetime of trace gases, and therefore atmospheric composition. Recent measurements [1] of free radicals made in forested environments characterized by low levels of nitrogen oxides (NOx = NO and NO2) indicate that current models of atmospheric chemistry tend to overestimate the concentration of peroxy radicals (HO2 and RO2). An overestimation of peroxy radicals is an important issue since these radicals are the main precursors of the hydroxyl radical (OH), the most important atmospheric oxidant during daytime. This issue could lead to a significant overestimation of the oxidative capacity of the global atmosphere since more than 86% of the Earth surface is covered by forests, oceans, and polar regions. An analysis of this dataset indicates that the missing sink could be due to an underestimation of the rates of RO2+HO2 reactions, and/or the uptake of peroxy radicals onto aerosol particles. A thorough evaluation of scientific studies published in the literature shows that there is a lack of kinetic and mechanistic data to correctly assess the contribution of these two loss pathways of peroxy radicals in low NOx environments. Classical molecular dynamics simulations, using the Gromacs package [2], are performed to study the interaction of HO2 with organic (carboxylic acid) aerosols. The effect of the presence of water molecules on the surface are also be investigated. These calculations provide theoretical values for observable quantities such as uptake and mass accommodation

  4. Development of panel loudspeaker system: design, evaluation and enhancement.

    PubMed

    Bai, M R; Huang, T

    2001-06-01

    Panel speakers are investigated in terms of structural vibration and acoustic radiation. A panel speaker primarily consists of a panel and an inertia exciter. Contrary to conventional speakers, flexural resonance is encouraged such that the panel vibrates as randomly as possible. Simulation tools are developed to facilitate system integration of panel speakers. In particular, electro-mechanical analogy, finite element analysis, and fast Fourier transform are employed to predict panel vibration and the acoustic radiation. Design procedures are also summarized. In order to compare the panel speakers with the conventional speakers, experimental investigations were undertaken to evaluate frequency response, directional response, sensitivity, efficiency, and harmonic distortion of both speakers. The results revealed that the panel speakers suffered from a problem of sensitivity and efficiency. To alleviate the problem, a woofer using electronic compensation based on H2 model matching principle is utilized to supplement the bass response. As indicated in the result, significant improvement over the panel speaker alone was achieved by using the combined panel-woofer system.

  5. Lipid Panel

    MedlinePlus

    ... Time and International Normalized Ratio (PT/INR) PSEN1 Quantitative Immunoglobulins Red Blood Cell (RBC) Antibody Identification Red ... typically includes a fasting lipid panel. Beyond that, research continues into the usefulness of other non-traditional ...

  6. Thin film concentrator panel development

    NASA Technical Reports Server (NTRS)

    Zimmerman, D. K.

    1982-01-01

    The development and testing of a rigid panel concept that utilizes a thin film reflective surface for application to a low-cost point-focusing solar concentrator is discussed. It is shown that a thin film reflective surface is acceptable for use on solar concentrators, including 1500 F applications. Additionally, it is shown that a formed steel sheet substrate is a good choice for concentrator panels. The panel has good optical properties, acceptable forming tolerances, environmentally resistant substrate and stiffeners, and adaptability to low to mass production rates. Computer simulations of the concentrator optics were run using the selected reflector panel design. Experimentally determined values for reflector surface specularity and reflectivity along with dimensional data were used in the analysis. The simulations provided intercept factor and net energy into the aperture as a function of aperture size for different surface errors and pointing errors. Point source and Sun source optical tests were also performed.

  7. On the Ising character of the quantum-phase transition in LiHoF4

    NASA Astrophysics Data System (ADS)

    Skomski, R.

    2016-05-01

    It is investigated how a transverse magnetic field affects the quantum-mechanical character of LiHoF4, a system generally considered as a textbook example for an Ising-like quantum-phase transition. In small magnetic fields, the low-temperature behavior of the ions is Ising-like, involving the nearly degenerate low-lying Jz = ± 8 doublet. However, as the transverse field increases, there is a substantial admixture of states having |Jz| < 8. Near the quantum-phase-transition field, the system is distinctively non-Ising like, and all Jz eigenstates yield ground-state contributions of comparable magnitude. A classical analog to this mechanism is the micromagnetic single point in magnets with uniaxial anisotropy. Since Ho3+ has J = 8, the ion's behavior is reminiscent of the classical limit (J = ∞), but quantum corrections remain clearly visible.

  8. Computational model for operation of 2 mum co-doped Tm,Ho solid state lasers.

    PubMed

    Louchev, Oleg A; Urata, Yoshiharu; Saito, Norihito; Wada, Satoshi

    2007-09-17

    A computational model for operation of co-doped Tm,Ho solid-state lasers is developed coupling (i) 8-level rate equations with (ii) TEM00 laser beam distribution, and (iii) complex heat dissipation model. Simulations done for Q-switched approximately 0.1 J giant pulse generation by Tm,Ho:YLF laser show that approximately 43% of the 785 nm light diode side-pumped energy is directly transformed into the heat inside the crystal, whereas approximately 45% is the spontaneously emitted radiation from (3)F(4), (5)I(7) , (3)H(4) and (3)H(5) levels. In water-cooled operation this radiation is absorbed inside the thermal boundary layer where the heat transfer is dominated by heat conduction. In high-power operation the resulting temperature increase is shown to lead to (i) significant decrease in giant pulse energy and (ii) thermal lensing.

  9. Outbrief - Long Life Rocket Engine Panel

    NASA Technical Reports Server (NTRS)

    Quinn, Jason Eugene

    2004-01-01

    This white paper is an overview of the JANNAF Long Life Rocket Engine (LLRE) Panel results from the last several years of activity. The LLRE Panel has met over the last several years in order to develop an approach for the development of long life rocket engines. Membership for this panel was drawn from a diverse set of the groups currently working on rocket engines (Le. government labs, both large and small companies and university members). The LLRE Panel was formed in order to determine the best way to enable the design of rocket engine systems that have life capability greater than 500 cycles while meeting or exceeding current performance levels (Specific Impulse and Thrust/Weight) with a 1/1,OOO,OOO likelihood of vehicle loss due to rocket system failure. After several meetings and much independent work the panel reached a consensus opinion that the primary issues preventing LLRE are a lack of: physics based life prediction, combined loads prediction, understanding of material microphysics, cost effective system level testing. and the inclusion of fabrication process effects into physics based models. With the expected level of funding devoted to LLRE development, the panel recommended that fundamental research efforts focused on these five areas be emphasized.

  10. Fabrication of Lower Section and Upper Forward Bulkhead Panels of the Multi-Bay Box and Panel Preparation

    NASA Technical Reports Server (NTRS)

    Velicki, Alexander; Linton, Kim; Hoffman, Krishna; Thrash, Patrick; Pickell, Robert; Turley, Robert

    2015-01-01

    NASA and the Boeing Co. have been working together under the Environmentally Responsible Aviation Project to develop stitched unitized structure for reduced weight, reduced fuel burn and reduced pollutants in the next generation of commercial aircraft. The structural concept being evaluated is PRSEUS (Pultruded Rod Stitched Efficient Unitized Structure). In the PRSEUS concept, dry carbon fabric, pultruded carbon rods, and foam are stitched together into large preforms. Then these preforms are infused with an epoxy resin into large panels in an out-of-autoclave process. These panels have stiffeners in the length-wise and width-wise directions but contain no fasteners because all stiffeners are stitched to the panel skin. This document contains a description of the fabrication of panels for use in the 30-foot-long Multi-Bay Box test article to be evaluated at NASA LaRC. The document also describes a panel which explores new PRSEUS concepts for applications beyond the Multi-Bay Box.

  11. AmeriFlux US-Ho1 Howland Forest (main tower)

    DOE Data Explorer

    Hollinger, David [USDA Forest Service; Hollinger, David [USDA Forest Service

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ho1 Howland Forest (main tower). Site Description - Closed conifer forest, minimal disturbance. References: Fernandez et al. (1993), Canadian Journal of Soil Science 73 317-328. Hollinger et al. (1999), Global Change Biology 5: 891-902. Savage KE, Davidson EA (2001), Global Biogeochemical Cycles 15 337-350. Scott et al. (2004), Environmental Management, Vol. 33, Supplement 1, pp. S9-S22. Hollinger et al. (2004), Global Change Biology 10: 1689-1706.

  12. AmeriFlux US-Ho2 Howland Forest (west tower)

    DOE Data Explorer

    Hollinger, David [USDA Forest Service; Hollinger, David [USDA Forest Service

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ho2 Howland Forest (west tower). Site Description - Closed conifer forest, minimal disturbance. References: Fernandez et al. (1993), Canadian Journal of Soil Science 73 317-328. Hollinger et al. (1999), Global Change Biology 5: 891-902. Savage KE, Davidson EA (2001), Global Biogeochemical Cycles 15 337-350. Scott et al. (2004), Environmental Management, Vol. 33, Supplement 1, pp. S9-S22. Hollinger et al. (2004), Global Change Biology 10: 1689-1706.

  13. AmeriFlux US-Ho3 Howland Forest (harvest site)

    DOE Data Explorer

    Hollinger, David [USDA Forest Service; Hollinger, David [USDA Forest Service

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Ho3 Howland Forest (harvest site). Site Description - Closed conifer forest, minimal disturbance. References: Fernandez et al. (1993), Canadian Journal of Soil Science 73 317-328. Hollinger et al. (1999), Global Change Biology 5: 891-902. Savage KE, Davidson EA (2001), Global Biogeochemical Cycles 15 337-350. Scott et al. (2004), Environmental Management, Vol. 33, Supplement 1, pp. S9-S22. Hollinger et al. (2004), Global Change Biology 10: 1689-1706.

  14. The infrared counterpart of the eclipsing X-ray binary HO253 + 193

    NASA Technical Reports Server (NTRS)

    Zuckerman, B.; Becklin, E. E.; Mclean, I. S.; Patterson, Joseph

    1992-01-01

    We report the identification of the infrared counterpart of the pulsating X-ray source HO253 + 193. It is a highly reddened star varying in K light with a period near 3 hr, but an apparent even-odd effect in the light curve implies that the true period is 6.06 hr. Together with the recent report of X-ray eclipses at the latter period, this establishes the close binary nature of the source. Infrared minimum occurs at X-ray minimum, certifying that the infrared variability arises from the tidal distortion of the lobe-filling secondary. The absence of a point source at radio wavelengths, plus the distance derived from the infrared data, suggests that the binary system is accidentally located behind the dense core of the molecular cloud Lynds 1457. The eclipses and pulsations in the X-ray light curve, coupled with the hard X-ray spectrum and low luminosity, demonstrate that HO253 + 193 contains an accreting magnetic white dwarf, and hence belongs to the 'DQ Herculis' class of cataclysmic variables.

  15. Can preoperative detrusor underactivity influence surgical outcomes of 120 W HPS vaporization of the prostate (PVP) or holmium laser enucleation of the prostate (HoLEP)? A serial 3-year follow-up study.

    PubMed

    Cho, Min Chul; Park, Juhyun; Kim, Jung Kwon; Cho, Sung Yong; Jeong, Hyeon; Oh, Seung-June; Paick, Jae-Seung; Son, Hwancheol

    2018-01-01

    To determine the influence of preoperative detrusor underactivity (DU) on serial long-term outcomes of HPS/PVP or HoLEP for LUTS/BPH, and to compare the influence between the two surgeries. A total of 382 men, who underwent 120W-HPS/PVP or HoLEP for LUTS/BPH and for whom 36-month follow-up data were available, were classified into four groups: HPS with DU (n = 145), HPS without DU (n = 44), HoLEP with DU (n = 105), and HoLEP without DU (n = 88). DU was defined as bladder contractility index of <100. Surgical outcomes were assessed at postoperative 6, 12, 24, and 36 months using IPSS, uroflowmetry, and serum PSA. All four groups maintained improvements in voiding symptom score (VSS), storage symptom score, total-IPSS, QOL index, maximum flow rate (Qmax), post-void residual urine volume (PVR), and bladder voiding efficiency (BVE) compared with baseline up to 3 years postoperatively. There were no significant differences in improvements of postoperative IPSS parameters including QOL index between men with and without DU throughout the follow-up period after HPS or HoLEP. In men with DU, there were no significant differences in improvements of postoperative QOL index, Qmax, PVR, or BVE between HPS and HoLEP groups throughout the follow-up period, except for VSS and total IPSS. Serum PSA reductions after HoLEP were greater than after PVP. Improvements in LUTS, Qmax, and BVE can maintain up to 3 years after HPS or HoLEP for LUTS/BPH, irrespective of the presence or absence of preoperative DU. Although HoLEP may provide more durable improvement of VS in men with DU than HPS, there seems to be no difference in improvement of QOL or Qmax or BVE between HPS and HoLEP. © 2017 Wiley Periodicals, Inc.

  16. Uncertainties in predicting solar panel power output

    NASA Technical Reports Server (NTRS)

    Anspaugh, B.

    1974-01-01

    The problem of calculating solar panel power output at launch and during a space mission is considered. The major sources of uncertainty and error in predicting the post launch electrical performance of the panel are considered. A general discussion of error analysis is given. Examples of uncertainty calculations are included. A general method of calculating the effect on the panel of various degrading environments is presented, with references supplied for specific methods. A technique for sizing a solar panel for a required mission power profile is developed.

  17. Reliability of stiffened structural panels: Two examples

    NASA Technical Reports Server (NTRS)

    Stroud, W. Jefferson; Davis, D. Dale, Jr.; Maring, Lise D.; Krishnamurthy, Thiagaraja; Elishakoff, Isaac

    1992-01-01

    The reliability of two graphite-epoxy stiffened panels that contain uncertainties is examined. For one panel, the effect of an overall bow-type initial imperfection is studied. The size of the bow is assumed to be a random variable. The failure mode is buckling. The benefits of quality control are explored by using truncated distributions. For the other panel, the effect of uncertainties in a strain-based failure criterion is studied. The allowable strains are assumed to be random variables. A geometrically nonlinear analysis is used to calculate a detailed strain distribution near an elliptical access hole in a wing panel that was tested to failure. Calculated strains are used to predict failure. Results are compared with the experimental failure load of the panel.

  18. Gas filled panel insulation

    DOEpatents

    Griffith, Brent T.; Arasteh, Dariush K.; Selkowitz, Stephen E.

    1993-01-01

    A structural or flexible highly insulative panel which may be translucent, is formed from multi-layer polymeric material in the form of an envelope surrounding a baffle. The baffle is designed so as to minimize heat transfer across the panel, by using material which forms substantially closed spaces to suppress convection of the low conductivity gas fill. At least a portion of the baffle carries a low emissivity surface for suppression of infrared radiation.

  19. Sound-proof Sandwich Panel Design via Metamaterial Concept

    NASA Astrophysics Data System (ADS)

    Sui, Ni

    Sandwich panels consisting of hollow core cells and two face-sheets bonded on both sides have been widely used as lightweight and strong structures in practical engineering applications, but with poor acoustic performance especially at low frequency regime. Basic sound-proof methods for the sandwich panel design are spontaneously categorized as sound insulation and sound absorption. Motivated by metamaterial concept, this dissertation presents two sandwich panel designs without sacrificing weight or size penalty: A lightweight yet sound-proof honeycomb acoustic metamateiral can be used as core material for honeycomb sandwich panels to block sound and break the mass law to realize minimum sound transmission; the other sandwich panel design is based on coupled Helmholtz resonators and can achieve perfect sound absorption without sound reflection. Based on the honeycomb sandwich panel, the mechanical properties of the honeycomb core structure were studied first. By incorporating a thin membrane on top of each honeycomb core, the traditional honeycomb core turns into honeycomb acoustic metamaterial. The basic theory for such kind of membrane-type acoustic metamaterial is demonstrated by a lumped model with infinite periodic oscillator system, and the negative dynamic effective mass density for clamped membrane is analyzed under the membrane resonance condition. Evanescent wave mode caused by negative dynamic effective mass density and impedance methods are utilized to interpret the physical phenomenon of honeycomb acoustic metamaterials at resonance. The honeycomb metamaterials can extraordinarily improve low-frequency sound transmission loss below the first resonant frequency of the membrane. The property of the membrane, the tension of the membrane and the numbers of attached membranes can impact the sound transmission loss, which are observed by numerical simulations and validated by experiments. The sandwich panel which incorporates the honeycomb metamateiral as

  20. Composite panels based on woven sandwich-fabric preforms

    NASA Astrophysics Data System (ADS)

    van Vuure, Aart Willem

    A new type of sandwich material was investigated, based on woven sandwich-fabric preforms. Because of the integrally woven nature of the sandwich-fabric the skin-core debonding resistance of panels and structures based on the preform is very high. As the sandwich-fabrics are produced by a large scale textile weaving process (velvet weaving or distance weaving) and already a preform of a sandwich is available, the cost of the final panel or structure can potentially stay limited. Most attention in this work is focussed on the mechanical performance of sandwich-fabric panels. The high skin-core debonding resistance was verified and also indications were found of a good damage tolerance. Both unfoamed and foamed panels were evaluated and compared with existing sandwich panels. Microstructural parameters investigated for unfoamed cores are pile length, pile density, woven pile angles, degree of pile stretching, tilt angles of the piles induced during panel production and resin content and distribution. For foamed panels it is especially the foam density which has an important influence. There appears to be a synergistic effect between piles and foam in the sandwich core, leading to very acceptable mechanical properties. For panels for (semi) structural applications, foaming is almost indispensable once the panel thickness is higher than about 15 mm. To understand the behaviour of foamed panels, attention was paid to the modelling of the mechanics of pure foam. The foam microstructure was modelled with the model of an anisotropic tetrakaidecahedron. The mechanical properties of unfoamed panels were modelled with the help of finite elements. A detailed geometrical description of the core layout was made which was incorporated into a preprocessing program for a finite element code. Attention is paid to the production of panels based on the woven preforms. A newly developed Adhesive Foil Stretching process was investigated. Also the foaming of panels was studied. A lot of

  1. Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pschirer, James; Burgess, Joshua; Schrecengost, Robert

    Alstom Power Inc., a wholly owned subsidiary of the General Electric Company (GE), has completed the project “Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development” under U.S. Department of Energy (DOE) Award Number DE-FE0024076. This project was part of DOE’s Novel Crosscutting Research and Development to Support Advanced Energy Systems program. AUSC Tube Membrane Panel Development was a two and one half year project to develop and verify the manufacturability and serviceability of welded tube membrane panels made from high performance materials suitable for the AUSC steam cycles, defined as high pressure steam turbine inlet conditions of 700-760°C (1292-1400°F) and 24.5-35MPamore » (3500-5000psi). The difficulty of this challenge lies in the fact that the membrane-welded construction imposes demands on the materials that are unlike any that exist in other parts of the boiler. Tube membrane panels have been designed, fabricated, and installed in boilers for over 50 years with relatively favorable experience when fabricated from carbon and Cr-Mo low alloy steels. The AUSC steam cycle requires membrane tube panels fabricated from materials that have not been used in a weldment with metal temperatures in the range of 582-610°C (1080-1130°F). Fabrication materials chosen for the tubing were Grade 92 and HR6W. Grade 92 is a creep strength enhanced ferritic Cr-Mo alloy and HR6W is a high nickel alloy. Once the materials were chosen, GE performed the engineering design of the panels, prepared shop manufacturing drawings, and developed manufacturing and inspection plans. After the materials were purchased, GE manufactured and inspected the tube membrane panels, determined if post fabrication heat treatment of the tube membrane panels was needed, performed pre- and post-weld heat treatment on the Grade 92 panels, conducted final nondestructive inspection of any heat treated tube membrane panels, conducted destructive inspection of the completed

  2. Fabric panel clean change-out frame

    DOEpatents

    Brown, Ronald M.

    1995-01-31

    A fabric panel clean change-out frame, for use on a containment structure having rigid walls, is formed of a compression frame and a closure panel. The frame is formed of elongated spacers, each carrying a plurality of closely spaced flat springs, and each having a hooked lip extending on the side of the spring facing the spacer. The closure panel is includes a perimeter frame formed of flexible, wedge-shaped frame members that are receivable under the springs to deflect the hooked lips. A groove on the flexible frame members engages the hooked lips and locks the frame members in place under the springs. A flexible fabric panel is connected to the flexible frame members and closes its center.

  3. 32 CFR 724.104 - NDRB Traveling Panel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false NDRB Traveling Panel. 724.104 Section 724.104 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL NAVAL DISCHARGE REVIEW BOARD Definitions § 724.104 NDRB Traveling Panel. An NDRB Panel that travels for the purpose of...

  4. Precast concrete sandwich panels subjected to impact loading

    NASA Astrophysics Data System (ADS)

    Runge, Matthew W.

    Precast concrete sandwich panels are a relatively new product in the construction industry. The design of these panels incorporates properties that allow for great resilience against temperature fluctuation as well as the very rapid and precise construction of facilities. The concrete sandwich panels investigated in this study represent the second generation of an ongoing research and development project. This second generation of panels have been engineered to construct midsized commercial buildings up to three stories in height as well as residential dwellings. The panels consist of a double-tee structural wythe, a foam core and a fascia wythe, joined by shear connectors. Structures constructed from these panels may be subjected to extreme loading including the effects of seismic and blast loading in addition to wind. The aim of this work was to investigate the behaviour of this particular sandwich panel when subjected to structural impact events. The experimental program consisted of fourteen concrete sandwich panels, five of which were considered full-sized specimens (2700 mm X 1200mm X 270 mm) and nine half-sized specimens (2700mm X 600mm X 270 mm) The panels were subjected to impact loads from a pendulum impact hammer where the total energy applied to the panels was varied by changing the mass of the hammer. The applied loads, displacements, accelerations, and strains at the mid-span of the panel as well as the reaction point forces were monitored during the impact. The behaviour of the panels was determined primarily from the experimental results. The applied loads at low energy levels that caused little to no residual deflection as well as the applied loads at high energy levels that represent catastrophic events and thus caused immediate failure were determined from an impact on the structural and the fascia wythes. Applied loads at intermediate energy levels representing extreme events were also used to determine whether or not the panels could withstand

  5. Minimally invasive scoliosis treatment with a Ho:YAG laser

    NASA Astrophysics Data System (ADS)

    Rumpf, Christian G.; Lang, Robert D.; Goetz, Marcus H.

    2000-11-01

    Today most surgical treatment of spinal deformations is concentrated on invasive mechanical techniques with long operation times and major effects on the patient's mobility. The proposed minimally invasive technique using laser light for tissue ablation offers a possibility of gentle scoliosis treatment. It is thought that an early removal of the epiphysial growth zone on the convex side over several vertebrae results in a straightening of the spine. In a first evaluation, four different laser systems including argon ion, Nd:YAG (Q-switched), Nd:YAG (cw), and Ho:YAG laser were compared with respect to thermal damage to adjacent tissue, ablation rates, efficiency and laser handling. For in-vivo investigation, fresh lamb spine was used. Comparison showed that the Ho:YAG laser is the most appropriate laser for the given goal, providing efficient photoablation with moderate thermal effects on the adjacent tissue. In a second step the proposed minimally invasive operation technique was performed in in-vivo experiments on young foxhounds using 3D- thoracoscopic operation techniques. During these operations temperature mapping was done using fiber-optic fluorescent probes. After 12 months of normal growth the animals were sacrificed and x-ray as well as MRI was performed on the spine. First results show a positive effect of scoliotic growth in two cases. Being able to produce a scoliosis by hemiepiphysiodesis on the vertebra, It is thought that this technique is successful for a straightening of the spine on patients with scoliosis.

  6. Hypersonic panel flutter in a rarefied atmosphere

    NASA Technical Reports Server (NTRS)

    Resende, Hugo B.

    1993-01-01

    Panel flutter is a form of dynamic aeroelastic instability resulting from the interaction between motion of an aircraft structural panel and the aerodynamic loads exerted on that panel by air flowing past one of the faces. It differs from lifting surface flutter in the sense that it is not usually catastrophic, the panel's motion being limited by nonlinear membrane stresses produced by the transverse displacement. Above some critical airflow condition, the linear instability grows to a limit cycle . The present investigation studies panel flutter in an aerodynamic regime known as 'free molecule flow', wherein intermolecular collisions can be neglected and loads are caused by interactions between individual molecules and the bounding surface. After collision with the panel, molecules may be reflected specularly or reemitted in diffuse fashion. Two parameters characterize this process: the 'momentum accommodation coefficient', which is the fraction of the specularly reflected molecules; and the ratio between the panel temperature and that of the free airstream. This model is relevant to the case of hypersonic flight vehicles traveling at very high altitudes and especially for panels oriented parallel to the airstream or in the vehicle's lee. Under these conditions the aerodynamic shear stress turns out to be considerably larger than the surface pressures, and shear effects must be included in the model. This is accomplished by means of distributed longitudinal and bending loads. The former can cause the panel to buckle. In the example of a simply-supported panel, it turns out that the second mode of free vibration tends to dominate the flutter solution, which is carried out by a Galerkin analysis. Several parametric studies are presented. They include the effects of (1) temperature ratio; (2) momentum accommodation coefficient; (3) spring parameters, which are associated with how the panel is connected to adjacent structures; (4) a parameter which relates compressive

  7. Highly efficient green up-conversion luminescence of Nd3+-Yb3+-Ho3+ codoped fluorite-type nanocrystals in transparent glass ceramics

    NASA Astrophysics Data System (ADS)

    Qiu, Jianbei; Kawamoto, Yoji; Zhang, Junjie

    2002-11-01

    Oxyfluoride glasses were developed with composition 30SiO2[middle dot]15AlO1.5[middle dot]28PbF2[middle dot]22CdF2[middle dot](4.8-x)GdF3[middle dot]0.1NdF3[middle dot]0.1HoF3[middle dot]xYbF3 (x=0, 0.1, 0.2, 0.5, 1, 2, 3, 4, and 4.8) in mole percent. Powder x-ray diffraction analysis revealed that the heat treatments of the oxyfluoride glasses at 450 degC for 0.5 h cause the precipitation of Nd3+-Yb3+-Ho3+ codoped fluorite-type nanocrystals of about 16.3 nm in diameter in the glass matrix. These transparent glass ceramics exhibited very strong green up-conversion luminescence due to the Ho3+: (5F4, 5S2)[right arrow]5I8 transition under 800 nm excitation. The intensity of the green up-conversion luminescence in a 1 mol % YbF3-containing glass ceramic was found to be about 120 times stronger than that in the precursor oxyfluoride glass. The reason for the highly efficient Ho3+ up-conversion luminescence in the oxyfluoride glass ceramics is discussed. An up-conversion mechanism is also proposed.

  8. Astaxanthin Induces the Nrf2/HO-1 Antioxidant Pathway in Human Umbilical Vein Endothelial Cells by Generating Trace Amounts of ROS.

    PubMed

    Niu, Tingting; Xuan, Rongrong; Jiang, Ligang; Wu, Wei; Zhen, Zhanghe; Song, Yuling; Hong, Lili; Zheng, Kaiqin; Zhang, Jiaxing; Xu, Qingshan; Tan, Yinghong; Yan, Xiaojun; Chen, Haimin

    2018-02-14

    Astaxanthin is a powerful antioxidant that possesses potent protective effects against various human diseases and physiological disorders. However, the mechanisms underlying its antioxidant functions in cells are not fully understood. In the present study, the effects of astaxanthin on reactive oxygen species (ROS) production and antioxidant enzyme activity, as well as mitogen-activated protein kinases (MAPKs), phosphatidylinositol 3-kinase (PI3K)/Akt, and the nuclear factor erythroid 2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) pathways in human umbilical vein endothelial cells (HUVECs), were examined. It was shown that astaxanthin (0.1, 1, and 10 μM) induced ROS production by 9.35%, 14.8%, and 18.06% compared to control, respectively, in HUVECs. In addition, astaxanthin increased the mRNA levels of phase II enzymes HO-1 and also promoted GSH-Px enzyme activity. Furthermore, we observed ERK phosphorylation, nuclear translocation of Nrf-2, and activation of antioxidant response element-driven luciferase activity upon astaxanthin treatment. Knockdown of Nrf-2 by small interfering RNA inhibited HO-1 mRNA expression by 60%, indicating that the Nrf-2/ARE signaling pathway is activated by astaxanthin. Our results suggest that astaxanthin activates the Nrf-2/HO-1 antioxidant pathway by generating small amounts of ROS.

  9. Endothelial HO-1 induction by model TG-rich lipoproteins is regulated through a NOX4-Nrf2 pathway1[S

    PubMed Central

    Latham Birt, Sally H.; Purcell, Robert; Botham, Kathleen M.; Wheeler-Jones, Caroline P. D.

    2016-01-01

    Circulating levels of chylomicron remnants (CMRs) increase postprandially and their composition directly reflects dietary lipid intake. These TG-rich lipoproteins likely contribute to the development of endothelial dysfunction, albeit via unknown mechanisms. Here, we investigated how the FA composition of CMRs influences their actions on human aortic endothelial cells (HAECs) by comparing the effects of model CMRs—artificial TG-rich CMR-like particles (A-CRLPs)—containing TGs extracted from fish, DHA-rich algal, corn, or palm oils. HAECs responded with distinct transcriptional programs according to A-CRLP TG content and oxidation status, with genes involved in antioxidant defense and cytoprotection most prominently affected by n-3 PUFA-containing A-CRLPs. These particles were significantly more efficacious inducers of heme oxygenase-1 (HO-1) than n-6 PUFA corn or saturated FA-rich palm CRLPs. Mechanistically, HO-1 induction by all CRLPs requires NADPH oxidase 4, with PUFA-containing particles additionally dependent upon mitochondrial reactive oxygen species. Activation of both p38 MAPK and PPARβ/δ culminates in increased nuclear factor erythroid 2-related factor 2 (Nrf2) expression/nuclear translocation and HO-1 induction. These studies define new molecular pathways coupling endothelial cell activation by model CMRs with adaptive regulation of Nrf2-dependent HO-1 expression and may represent key mechanisms through which dietary FAs differentially impact progression of endothelial dysfunction. PMID:27185859

  10. Technical note: Evaluation of the simultaneous measurements of mesospheric OH, HO2, and O3 under a photochemical equilibrium assumption - a statistical approach

    NASA Astrophysics Data System (ADS)

    Kulikov, Mikhail Y.; Nechaev, Anton A.; Belikovich, Mikhail V.; Ermakova, Tatiana S.; Feigin, Alexander M.

    2018-05-01

    This Technical Note presents a statistical approach to evaluating simultaneous measurements of several atmospheric components under the assumption of photochemical equilibrium. We consider simultaneous measurements of OH, HO2, and O3 at the altitudes of the mesosphere as a specific example and their daytime photochemical equilibrium as an evaluating relationship. A simplified algebraic equation relating local concentrations of these components in the 50-100 km altitude range has been derived. The parameters of the equation are temperature, neutral density, local zenith angle, and the rates of eight reactions. We have performed a one-year simulation of the mesosphere and lower thermosphere using a 3-D chemical-transport model. The simulation shows that the discrepancy between the calculated evolution of the components and the equilibrium value given by the equation does not exceed 3-4 % in the full range of altitudes independent of season or latitude. We have developed a statistical Bayesian evaluation technique for simultaneous measurements of OH, HO2, and O3 based on the equilibrium equation taking into account the measurement error. The first results of the application of the technique to MLS/Aura data (Microwave Limb Sounder) are presented in this Technical Note. It has been found that the satellite data of the HO2 distribution regularly demonstrate lower altitudes of this component's mesospheric maximum. This has also been confirmed by model HO2 distributions and comparison with offline retrieval of HO2 from the daily zonal means MLS radiance.

  11. Shear-Panel Test Fixture Eliminates Corner Stresses

    NASA Technical Reports Server (NTRS)

    Kiss, J. J.; Farley, G. L.; Baker, D. J.

    1984-01-01

    New design eliminates corner stresses while maintaining uniform stress across panel. Shear panel test fixture includes eight frames and eight corner pins. Fixture assembled in two halves with shear panel sandwiched in between. Results generated from this fixture will result in good data base for design of efficient aircraft structures and other applications.

  12. Small inlet optical panel and a method of making a small inlet optical panel

    DOEpatents

    Veligdan, James T.; Slobodin, David

    2001-01-01

    An optical panel having a small inlet, and a method of making a small inlet optical panel, are disclosed, which optical panel includes a individually coating, stacking, and cutting a first plurality of stacked optical waveguides to form an outlet face body with an outlet face, individually coating, stacking, and cutting a second plurality of stacked optical waveguides to form an inlet face body with an inlet face, and connecting an optical coupling element to the first plurality and to the second plurality, wherein the optical coupling element redirects light along a parallel axis of the inlet face to a parallel axis of the outlet face. In the preferred embodiment of the present invention, the inlet face is disposed obliquely with and askew from the outlet face.

  13. Photoelectric panel with equatorial mounting of drive

    NASA Astrophysics Data System (ADS)

    Kukhta, M. S.; Krauinsh, P. Y.; Krauinsh, D. P.; Sokolov, A. P.; Mainy, S. B.

    2018-03-01

    The relevance of the work is determined by the need to create effective models for sunny energy. The article considers a photoelectric panel equipped with a system for tracking the sun. Efficiency of the system is provided by equatorial mounting, which compensates for the rotation of the Earth by rotating the sunny panel in the plane of the celestial equator. The specificity of climatic and geographical conditions of Tomsk is estimated. The dynamics of power variations of photoelectric panels with equatorial mounting during seasonal fluctuations in Tomsk is calculated. A mobile photovoltaic panel with equatorial mounting of the drive has been developed. The methods of design strategy for placing photovoltaic panels in the architectural environment of the city are presented. Key words: sunny energy, photovoltaics, equatorial mounting, mechatronic model, wave reducer, electric drive.

  14. Propulsion Systems Panel deliberations

    NASA Technical Reports Server (NTRS)

    Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; Mcgaw, Mike; Munafo, Paul M.

    1993-01-01

    The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

  15. Gas filled panel insulation

    DOEpatents

    Griffith, B.T.; Arasteh, D.K.; Selkowitz, S.E.

    1993-12-14

    A structural or flexible highly insulative panel which may be translucent, is formed from multi-layer polymeric material in the form of an envelope surrounding a baffle. The baffle is designed so as to minimize heat transfer across the panel, by using material which forms substantially closed spaces to suppress convection of the low conductivity gas fill. At least a portion of the baffle carries a low emissivity surface for suppression of infrared radiation. 18 figures.

  16. Propulsion Systems Panel deliberations

    NASA Astrophysics Data System (ADS)

    Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; McGaw, Mike; Munafo, Paul M.

    1993-02-01

    The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

  17. Retaining Ring Fastener for Solar Panels

    NASA Technical Reports Server (NTRS)

    Wilson, A. H.

    1983-01-01

    Simple articulating linkage secures solar panels into supporting framework. Five element linkage collapses into W-shape for easy placement into framework, then expands to form rectangle of same dimensions as those of panel.

  18. Ho:YAG Single Crystal Fiber: Fabrication and Optical Characterization

    DTIC Science & Technology

    2014-06-16

    between the 5I8 and 5I7 energy levels. The results verified the absorption peaks suitable for in- band direct pumping at 1908 nm and 1932 nm with the...Efficient high-power Ho:YAG laser directly in- band pumped by a GaSb -based laser diode stack at 1.9 μm,” Appl. Phys. B 106(2), 315–319 (2012). 21. M...characterized for its optical absorption and emission properties involving transitions between the 5I8 and 5I7 energy levels. The results verified

  19. Modified first-order Hořava-Lifshitz gravity: Hamiltonian analysis of the general theory and accelerating FRW cosmology in a power-law F(R) model

    NASA Astrophysics Data System (ADS)

    Carloni, Sante; Chaichian, Masud; Nojiri, Shin'Ichi; Odintsov, Sergei D.; Oksanen, Markku; Tureanu, Anca

    2010-09-01

    We propose the most general modified first-order Hořava-Lifshitz gravity, whose action does not contain time derivatives higher than the second order. The Hamiltonian structure of this theory is studied in all the details in the case of the spatially-flat Friedmann-Robertson-Walker (FRW) space-time, demonstrating many of the features of the general theory. It is shown that, with some plausible assumptions, including the projectability of the lapse function, this model is consistent. As a large class of such theories, the modified Hořava-Lifshitz F(R) gravity is introduced. The study of its ultraviolet properties shows that its z=3 version seems to be renormalizable in the same way as the original Hořava-Lifshitz proposal. The Hamiltonian analysis of the modified Hořava-Lifshitz F(R) gravity shows that it is in general a consistent theory. The F(R) gravity action is also studied in the fixed-gauge form, where the appearance of a scalar field is particularly illustrative. Then the spatially-flat FRW cosmology for this F(R) gravity is investigated. It is shown that a special choice of parameters for this theory leads to the same equations of motion as in the case of traditional F(R) gravity. Nevertheless, the cosmological structure of the modified Hořava-Lifshitz F(R) gravity turns out to be much richer than for its traditional counterpart. The emergence of multiple de Sitter solutions indicates the possibility of unification of early-time inflation with late-time acceleration within the same model. Power-law F(R) theories are also investigated in detail. It is analytically shown that they have a quite rich cosmological structure: early-/late-time cosmic acceleration of quintessence, as well as of phantom types. Also it is demonstrated that all the four known types of finite-time future singularities may occur in the power-law Hořava-Lifshitz F(R) gravity. Finally, a covariant proposal for (renormalizable) F(R) gravity within the Hořava-Lifshitz spirit is

  20. Single-Mode, High Repetition Rate, Compact Ho:YLF Laser for Space-Borne Lidar Applications

    NASA Technical Reports Server (NTRS)

    Bai, Yingxin; Yu, Jirong; Wong, Teh-Hwa; Chen, Songsheng; Petros, Mulugeta; Singh, Upendra N.

    2014-01-01

    A single transverse/longitudinal mode, compact Q-switched Ho:YLF laser has been designed and demonstrated for space-borne lidar applications. The pulse energy is between 34-40 mJ for 100-200 Hz operation. The corresponding peak power is >1 MW.