Sample records for ga-9 legal weight

  1. 49 CFR 9.9 - Legal proceedings between private litigants: General rules.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...: General rules. 9.9 Section 9.9 Transportation Office of the Secretary of Transportation TESTIMONY OF EMPLOYEES OF THE DEPARTMENT AND PRODUCTION OF RECORDS IN LEGAL PROCEEDINGS § 9.9 Legal proceedings between... provided in §§ 9.13 and 9.15 of this part, not to serve a demand on the employee. Whenever, in a legal...

  2. 7 CFR 760.9 - Other legal recourse.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Other legal recourse. 760.9 Section 760.9 Agriculture... Milk § 760.9 Other legal recourse. (a) No indemnity payment shall be made for contaminated milk... application, the Deputy Administrator determines that other legal recouse is available to the farmer. An...

  3. 21 CFR 120.9 - Legal basis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Legal basis. 120.9 Section 120.9 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.9 Legal basis...

  4. 21 CFR 120.9 - Legal basis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Legal basis. 120.9 Section 120.9 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.9 Legal basis...

  5. 21 CFR 120.9 - Legal basis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Legal basis. 120.9 Section 120.9 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.9 Legal basis...

  6. 21 CFR 120.9 - Legal basis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Legal basis. 120.9 Section 120.9 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.9 Legal basis...

  7. 21 CFR 120.9 - Legal basis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Legal basis. 120.9 Section 120.9 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.9 Legal basis...

  8. Exploring the radiosynthesis and in vitro characteristics of [68 Ga]Ga-DOTA-Siglec-9.

    PubMed

    Jensen, Svend B; Käkelä, Meeri; Jødal, Lars; Moisio, Olli; Alstrup, Aage K O; Jalkanen, Sirpa; Roivainen, Anne

    2017-07-01

    Vascular adhesion protein 1 is a leukocyte homing-associated glycoprotein, which upon inflammation rapidly translocates from intracellular sources to the endothelial cell surface. It has been discovered that the cyclic peptide residues 283-297 of sialic acid-binding IgG-like lectin 9 (Siglec-9) "CARLSLSWRGLTLCPSK" bind to vascular adhesion protein 1 and hence makes the radioactive analogues of this compound ([ 68 Ga]Ga-DOTA-Siglec-9) interesting as a noninvasive visualizing marker of inflammation. Three different approaches to the radiosynthesis of [ 68 Ga]Ga-DOTA-Siglec-9 are presented and compared with previously published methods. A simple, robust radiosynthesis of [ 68 Ga]Ga-DOTA-Siglec-9 with a yield of 62% (non decay-corrected) was identified, and it had a radiochemical purity >98% and a specific radioactivity of 35 MBq/nmol. Furthermore, the protein binding and stability of [ 68 Ga]Ga-DOTA-Siglec-9 were analyzed in vitro in mouse, rat, rabbit, pig, and human plasma and compared with in vivo pig results. The plasma in vitro protein binding of [ 68 Ga]Ga-DOTA-Siglec-9 was the lowest in the pig followed by rabbit, human, rat, and mouse. It was considerably higher in the in vivo pig experiments. The in vivo stability in pigs was lower than the in vitro stability. Despite considerable species differences, the observed characteristics of [ 68 Ga]Ga-DOTA-Siglec-9 are suitable as a positron emission tomography tracer. Copyright © 2017 John Wiley & Sons, Ltd.

  9. 5 CFR 1604.9 - Court orders and legal processes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Court orders and legal processes. 1604.9 Section 1604.9 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD UNIFORMED SERVICES ACCOUNTS § 1604.9 Court orders and legal processes. A TSP account can be divided in an action for divorce...

  10. Preclinical evaluation of potential infection-imaging probe [68 Ga]Ga-DOTA-K-A9 in sterile and infectious inflammation.

    PubMed

    Nielsen, Karin M; Jørgensen, Nis P; Kyneb, Majbritt H; Borghammer, Per; Meyer, Rikke L; Thomsen, Trine R; Bender, Dirk; Jensen, Svend B; Nielsen, Ole L; Alstrup, Aage K O

    2018-05-23

    The development of bacteria-specific infection radiotracers is of considerable interest to improve diagnostic accuracy and enabling therapy monitoring. The aim of this study was to determine if the previously reported radiolabelled 1,4,7,10-tetraazacyclododecane-N,N',N″,N‴-tetraacetic acid (DOTA) conjugated peptide [ 68 Ga]Ga-DOTA-K-A9 could detect a staphylococcal infection in vivo and distinguish it from aseptic inflammation. An optimized [ 68 Ga]Ga-DOTA-K-A9 synthesis omitting the use of acetone was developed, yielding 93 ± 0.9% radiochemical purity. The in vivo infection binding specificity of [ 68 Ga]Ga-DOTA-K-A9 was evaluated by micro positron emission tomography/magnetic resonance imaging of 15 mice with either subcutaneous Staphylococcus aureus infection or turpentine-induced inflammation and compared with 2-deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG). The scans showed that [ 68 Ga]Ga-DOTA-K-A9 accumulated in all the infected mice at injected doses ≥3.6 MBq. However, the tracer was not found to be selective towards infection, since the [ 68 Ga]Ga-DOTA-K-A9 also accumulated in mice with inflammation. In a concurrent in vitro binding evaluation performed with a 5-carboxytetramethylrhodamine (TAMRA) fluorescence analogue of the peptide, TAMRA-K-A9, the microscopy results suggested that TAMRA-K-A9 bound to an intracellular epitope and therefore preferentially targeted dead bacteria. Thus, the [ 68 Ga]Ga-DOTA-K-A9 uptake observed in vivo is presumably a combination of local hyperemia, vascular leakiness and/or binding to an epitope present in dead bacteria. Copyright © 2018 John Wiley & Sons, Ltd.

  11. Comparison of 68Ga-DOTA-Siglec-9 and 18F-Fluorodeoxyribose-Siglec-9: Inflammation Imaging and Radiation Dosimetry.

    PubMed

    Virtanen, Helena; Silvola, Johanna M U; Autio, Anu; Li, Xiang-Guo; Liljenbäck, Heidi; Hellberg, Sanna; Siitonen, Riikka; Ståhle, Mia; Käkelä, Meeri; Airaksinen, Anu J; Helariutta, Kerttuli; Tolvanen, Tuula; Veres, Tibor Z; Saraste, Antti; Knuuti, Juhani; Jalkanen, Sirpa; Roivainen, Anne

    2017-01-01

    Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a ligand of inflammation-inducible vascular adhesion protein-1 (VAP-1). We compared 68 Ga-DOTA- and 18 F-fluorodeoxyribose- (FDR-) labeled Siglec-9 motif peptides for PET imaging of inflammation. Methods . Firstly, we examined 68 Ga-DOTA-Siglec-9 and 18 F-FDR-Siglec-9 in rats with skin/muscle inflammation. We then studied 18 F-FDR-Siglec-9 for the detection of inflamed atherosclerotic plaques in mice and compared it with previous 68 Ga-DOTA-Siglec-9 results. Lastly, we estimated human radiation dosimetry from the rat data. Results . In rats, 68 Ga-DOTA-Siglec-9 (SUV, 0.88 ± 0.087) and 18 F-FDR-Siglec-9 (SUV, 0.77 ± 0.22) showed comparable ( P = 0.29) imaging of inflammation. In atherosclerotic mice, 18 F-FDR-Siglec-9 detected inflamed plaques with a target-to-background ratio (1.6 ± 0.078) similar to previously tested 68 Ga-DOTA-Siglec-9 ( P = 0.35). Human effective dose estimates for 68 Ga-DOTA-Siglec-9 and 18 F-FDR-Siglec-9 were 0.024 and 0.022 mSv/MBq, respectively. Conclusion . Both tracers are suitable for PET imaging of inflammation. The easier production and lower cost of 68 Ga-DOTA-Siglec-9 present advantages over 18 F-FDR-Siglec-9, indicating it as a primary choice for clinical studies.

  12. Rht18 Semidwarfism in Wheat Is Due to Increased GA 2-oxidaseA9 Expression and Reduced GA Content1[OPEN

    PubMed Central

    Karafiatova, Miroslava; Uauy, Cristobal

    2018-01-01

    Semidwarfing genes have improved crop yield by reducing height, improving lodging resistance, and allowing plants to allocate more assimilates to grain growth. In wheat (Triticum aestivum), the Rht18 semidwarfing gene was identified and deployed in durum wheat before it was transferred into bread wheat, where it was shown to have agronomic potential. Rht18, a dominant and gibberellin (GA) responsive mutant, is genetically and functionally distinct from the widely used GA-insensitive semidwarfing genes Rht-B1b and Rht-D1b. In this study, the Rht18 gene was identified by mutagenizing the semidwarf durum cultivar Icaro (Rht18) and generating mutants with a range of tall phenotypes. Isolating and sequencing chromosome 6A of these “overgrowth” mutants showed that they contained independent mutations in the coding region of GA2oxA9. GA2oxA9 is predicted to encode a GA 2-oxidase that metabolizes GA biosynthetic intermediates into inactive products, effectively reducing the amount of bioactive GA (GA1). Functional analysis of the GA2oxA9 protein demonstrated that GA2oxA9 converts the intermediate GA12 to the inactive metabolite GA110. Furthermore, Rht18 showed higher expression of GA2oxA9 and lower GA content compared with its tall parent. These data indicate that the increased expression of GA2oxA9 in Rht18 results in a reduction of both bioactive GA content and plant height. This study describes a height-reducing mechanism that can generate new genetic diversity for semidwarfism in wheat by combining increased expression with mutations of specific amino acid residues in GA2oxA9. PMID:29545269

  13. 7 CFR 981.9 - Kernel weight.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Kernel weight. 981.9 Section 981.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 981.9 Kernel weight. Kernel weight means the weight of kernels, including...

  14. Aggregation-prone c9FTD/ALS poly(GA) RAN-translated proteins cause neurotoxicity by inducing ER stress.

    PubMed

    Zhang, Yong-Jie; Jansen-West, Karen; Xu, Ya-Fei; Gendron, Tania F; Bieniek, Kevin F; Lin, Wen-Lang; Sasaguri, Hiroki; Caulfield, Thomas; Hubbard, Jaime; Daughrity, Lillian; Chew, Jeannie; Belzil, Veronique V; Prudencio, Mercedes; Stankowski, Jeannette N; Castanedes-Casey, Monica; Whitelaw, Ena; Ash, Peter E A; DeTure, Michael; Rademakers, Rosa; Boylan, Kevin B; Dickson, Dennis W; Petrucelli, Leonard

    2014-10-01

    The occurrence of repeat-associated non-ATG (RAN) translation, an atypical form of translation of expanded repeats that results in the synthesis of homopolymeric expansion proteins, is becoming more widely appreciated among microsatellite expansion disorders. Such disorders include amyotrophic lateral sclerosis and frontotemporal dementia caused by a hexanucleotide repeat expansion in the C9ORF72 gene (c9FTD/ALS). We and others have recently shown that this bidirectionally transcribed repeat is RAN translated, and the "c9RAN proteins" thusly produced form neuronal inclusions throughout the central nervous system of c9FTD/ALS patients. Nonetheless, the potential contribution of c9RAN proteins to disease pathogenesis remains poorly understood. In the present study, we demonstrate that poly(GA) c9RAN proteins are neurotoxic and may be implicated in the neurodegenerative processes of c9FTD/ALS. Specifically, we show that expression of poly(GA) proteins in cultured cells and primary neurons leads to the formation of soluble and insoluble high molecular weight species, as well as inclusions composed of filaments similar to those observed in c9FTD/ALS brain tissues. The expression of poly(GA) proteins is accompanied by caspase-3 activation, impaired neurite outgrowth, inhibition of proteasome activity, and evidence of endoplasmic reticulum (ER) stress. Of importance, ER stress inhibitors, salubrinal and TUDCA, provide protection against poly(GA)-induced toxicity. Taken together, our data provide compelling evidence towards establishing RAN translation as a pathogenic mechanism of c9FTD/ALS, and suggest that targeting the ER using small molecules may be a promising therapeutic approach for these devastating diseases.

  15. New insights into the application of the valence rules in Zintl phases—Crystal and electronic structures of Ba{sub 7}Ga{sub 4}P{sub 9}, Ba{sub 7}Ga{sub 4}As{sub 9}, Ba{sub 7}Al{sub 4}Sb{sub 9}, Ba{sub 6}CaAl{sub 4}Sb{sub 9}, and Ba{sub 6}CaGa{sub 4}Sb{sub 9}

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

    He, Hua; Stoyko, Stanislav; Bobev, Svilen, E-mail: bobev@udel.edu

    Crystals of three new ternary pnictides—Ba{sub 7}Al{sub 4}Sb{sub 9}, Ba{sub 7}Ga{sub 4}P{sub 9}, and Ba{sub 7}Ga{sub 4}As{sub 9} have been prepared by reactions of the respective elements in molten Al or Pb fluxes. Single-crystal X-ray diffraction studies reveal that the three phases are isotypic, crystallizing in the orthorhombic Ba{sub 7}Ga{sub 4}Sb{sub 9}-type structure (space group Pmmn, Pearson symbol oP40, Z=2), for which only the prototype is known. The structure is based on TrPn{sub 4} tetrahedra (Tr=Al, Ga; Pn=P, As, Sb), connected in an intricate scheme into 1D-ribbons. Long interchain Pn–Pn bonds (d{sub P–P}>3.0 Å; d{sub As–As}>3.1 Å; d{sub Sb–Sb}>3.3 Å)more » account for the realization of 2D-layers, separated by Ba{sup 2+} cations. Applying the classic valance rules to rationalize the bonding apparently fails, and Ba{sub 7}Ga{sub 4}Sb{sub 9} has long been known as a metallic Zintl phase. Earlier theoretical calculations, both empirical and ab-initio, suggest that the possible metallic properties originate from filled anti-bonding Pn–Pn states, and the special roles of the “cations” in this crystal structure. To experimentally probe this hypothesis, we sought to synthesize the ordered quaternary phases Ba{sub 6}CaTr{sub 4}Sb{sub 9} (Tr=Al, Ga). Single-crystal X-ray diffraction work confirms Ba{sub 6.145(3)}Ca{sub 0.855}Al{sub 4}Sb{sub 9} and Ba{sub 6.235(3)}Ca{sub 0.765}Ga{sub 4}Sb{sub 9}, with Ca atoms preferably substituting Ba on one of the three available sites. The nuances of the five crystal structures are discussed, and the chemical bonding in Ba{sub 7}Ga{sub 4}As{sub 9} is interrogated by tight-binding linear muffin-tin orbital calculations. - Graphical abstract: The new Zintl phases—Ba{sub 7}Al{sub 4}Sb{sub 9}, Ba{sub 7}Ga{sub 4}P{sub 9}, and Ba{sub 7}Ga{sub 4}As{sub 9}, and their quaternary variants Ba{sub 6}CaTr{sub 4}Sb{sub 9} (Tr=Al, Ga)—crystallize in the Ba{sub 7}Ga{sub 4}Sb{sub 9} structure type. The structures

  16. 68Ga-DOTA-Siglec-9--a new imaging tool to detect synovitis.

    PubMed

    Virtanen, Helena; Autio, Anu; Siitonen, Riikka; Liljenbäck, Heidi; Saanijoki, Tiina; Lankinen, Petteri; Mäkilä, Jussi; Käkelä, Meeri; Teuho, Jarmo; Savisto, Nina; Jaakkola, Kimmo; Jalkanen, Sirpa; Roivainen, Anne

    2015-11-03

    Vascular adhesion protein-1 (VAP-1) is an adhesion molecule, which upon inflammation is rapidly translocated from intracellular sources to the endothelial cell surface. We have recently discovered that sialic acid- binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1 and that 68Ga-labeled Siglec-9 motif peptide facilitates in vivo imaging of inflammation. This study evaluated the feasibility of 68Ga-DOTA-Siglec-9 positron emission tomography (PET) for the assessment of synovitis. Rabbits with synovial inflammation were injected with 18F-FDG or 68Ga-DOTA-Siglec-9 and studied by gamma counting and autoradiography. Certain rabbits were also examined with magnetic resonance imaging (MRI). After PET imaging, rabbits were intravenously administered with anti-VAP-1 antibody to evaluate luminal expression of VAP-1 by immunohistochemistry. Finally, binding of Siglec-9 peptide and VAP-1 positive vessels were evaluated by double staining of rheumatoid arthritis synovium. Intra-articular injection of hemagglutinin induced mild synovial inflammation in rabbit knee with luminal expression of VAP-1. Synovitis was clearly visualized by 68Ga-DOTA-Siglec-9 PET in addition to 18F-FDG-PET and MRI. Compared with the 18F-FDG, the ex vivo inflamed-to-control synovium ratio of 68Ga-DOTA-Siglec-9 was similar (1.7 ± 0.4 vs. 1.5 ± 0.2, P = 0.32). Double staining revealed that Siglec-9 peptide binds to VAP-1 positive vessels in human rheumatoid synovium. Ga-DOTA-Siglec-9 PET tracer detected VAP-1 positive vasculature in the mild synovitis of rabbits comparable with 18F-FDG, suggesting its potential for in vivo imaging of synovial inflammation in patients with rheumatic diseases.

  17. Customized weight curves for Spanish fetuses and newborns.

    PubMed

    González González, Nieves Luisa; González Dávila, Enrique; Cabrera, Francisco; Padrón, Erika; Castro, José Ramon; García Hernández, José Angel

    2014-09-01

    To construct a model of customized birthweight curves for use in a Spanish population. Data of 20 331 newborns were used to construct a customized birthweight model. Multiple regression analysis was performed with newborn weight as the dependent variable and gestational age (GA), sex and maternal (M) weight, height, parity and ethnic origin as the independent variables. Using the new model, 27,507 newborns were classified as adequate for GA (AGA), large for GA (LGA) or small for GA (SGA). The results were compared with those of other customized and non-customized models. The resulting formula for the calculation of optimal neonatal weight was: Optimum weight (g) = 3289.681 + 135.413*GA40-14.063*GA40(2)-0.838*GA40(3) + 113.889 (if multiparous) + 165.560 (if origin = Asia) + 161.550 (South America) + 67.927 (rest of Europe) +109.265 (North Africa) + 9.392*Maternal-Height + 4.856*Maternal-Weight-0.098*Maternal-Weight(2) + 0.001*Maternal-Weight(3) + 67.188*Sex + GA40*(6.890*Sex + 9.032 (If multiparous) +0.006*Maternal-Height(3) + 0.260*Maternal-Weight) + GA40(2) (-0.378*Maternal-Height - 0.008*Maternal-Height(2)) + GA40(3) (-0.032*Maternal-Height). Weight percentiles were obtained from standard data using optimum weight variation coefficient. Agreement between our customized model and other Spanish models was "good" (κ = 0.717 and κ = 0.736; p < 0.001). Our model is comparable to other Spanish models, but offers the advantage of being customized, updated and freely available on the web. The 30.6% of infants classified as SGA using our model would be considered as AGA following a non-customized model.

  18. Magnetic Properties and Magnetic Phase Diagrams of Trigonal DyNi3Ga9

    NASA Astrophysics Data System (ADS)

    Ninomiya, Hiroki; Matsumoto, Yuji; Nakamura, Shota; Kono, Yohei; Kittaka, Shunichiro; Sakakibara, Toshiro; Inoue, Katsuya; Ohara, Shigeo

    2017-12-01

    We report the crystal structure, magnetic properties, and magnetic phase diagrams of single crystalline DyNi3Ga9 studied using X-ray diffraction, electrical resistivity, specific heat, and magnetization measurements. DyNi3Ga9 crystallizes in the chiral structure with space group R32. The dysprosium ions, which are responsible for the magnetism in this compound, form a two-dimensional honeycomb structure on a (0001) plane. We show that DyNi3Ga9 exhibits successive phase transitions at TN = 10 K and T'N = 9 K. The former suggests quadrupolar ordering, and the latter is attributed to the antiferromagnetic order. It is considered that DyNi3Ga9 forms the canted-antiferromagnetic structure below T'N owing to a small hysteresis loop of the low-field magnetization curve. We observe the strong easy-plane anisotropy, and the multiple-metamagnetic transitions with magnetization-plateaus under the field applied along the honeycomb plane. For Hallel [2\\bar{1}\\bar{1}0], the plateau-region arises every 1/6 for saturation magnetization. The magnetic phase diagrams of DyNi3Ga9 are determined for the fields along principal-crystal axes.

  19. 1.9 kV AlGaN/GaN Lateral Schottky Barrier Diodes on Silicon

    DOE PAGES

    Zhu, Mingda; Song, Bo; Qi, Meng; ...

    2015-02-16

    In this letter, we present AlGaN/GaN lateral Schottky barrier diodes on silicon with recessed anodes and dual field plates. A low specific on-resistance R ON,SP (5.12 mΩ · cm 2), a low turn-on voltage (<0.7 V) and a high reverse breakdown voltage BV (>1.9 kV), were simultaneously achieved in devices with a 25 μm anode/cathode separation, resulting in a power figure-of-merit (FOM) BV2/R ON,SP of 727 MW·cm 2. The record high breakdown voltage of 1.9 kV is attributed to the dual field plate structure.

  20. 31 CFR 215.9 - Change of legal residence by members of the Armed Forces.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Change of legal residence by members... Withholding Agreement § 215.9 Change of legal residence by members of the Armed Forces. (a) In determining the... change of legal residence of a member of the Armed Forces shall become effective for tax withholding...

  1. 31 CFR 215.9 - Change of legal residence by members of the Armed Forces.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Change of legal residence by members... Withholding Agreement § 215.9 Change of legal residence by members of the Armed Forces. (a) In determining the... change of legal residence of a member of the Armed Forces shall become effective for tax withholding...

  2. Photoemission Studies of Kondo Lattice Compounds YbNi3(Ga1-xAlx)9

    NASA Astrophysics Data System (ADS)

    Utsumi, Yuki; Sato, Hitoshi; Nagata, Heisuke; Kodama, Junichi; Ohara, Shigeo; Yamashita, Tetsuro; Mimura, Kojiro; Motonami, Satoru; Arita, Masashi; Ueda, Shigenori; Shimada, Kenya; Namatame, Hirofumi; Taniguchi, Masaki

    We have investigated the electronic structure of YbNi3 (Ga1-xAlx)9 (x = 0, 0.05, 0.10, 0.15) by means of hard x-ray (hν ˜ 6 keV) and low energy (hν ˜ 7 eV) photoemission spectroscopies (HAXPES and LEPES). Both Yb2+ and Yb3+ components are observed in the Yb 3d HAXPES spectra, which is an evidence of the valence fluctuation in YbNi3(Ga1-xAlx)9. A substitution of an Al ion for a Ga ion in YbNi3Ga9 changes the Yb ion into a trivalent state. The LEPES spectra of YbNi3Ga9 clearly exhibit the Kondo peak near the Fermi level (EF) and the Kondo temperature is estimated to be TK ˜ 550 K. With the Al substitution, the Kondo peak is shifted toward EF, indicating the decrease of TK

  3. Influence of the heterostructure design on the optical properties of GaN and Al0.1Ga0.9N quantum dots for ultraviolet emission

    NASA Astrophysics Data System (ADS)

    Matta, S.; Brault, J.; Ngo, T. H.; Damilano, B.; Korytov, M.; Vennéguès, P.; Nemoz, M.; Massies, J.; Leroux, M.; Gil, B.

    2017-08-01

    The optical properties of AlyGa1-yN quantum dots (QDs), with y = 0 or y = 0.1, in an AlxGa1-xN matrix are studied. The influence of the QD layer design is investigated pointing out the correlations between the QD structural and optical properties. In a first part, the role of the epitaxial strain in the dot self-assembling process is studied by fabricating GaN QD layers on different AlxGa1-xN layers with 0.5 ≤ x ≤ 0.7. Photoluminescence (PL) measurements show the main influence of the increase of the internal electric field (Fint) on the QD optical response inducing a strong red shift in the emission energy as x increases. Time resolved combined with temperature dependent PL measurements enabled the estimation of the QD internal quantum efficiencies at low temperature showing values around 50%. In addition, a PL integrated intensity ratio up to 74% is shown, between 300 and 9 K. In the second part, the design of Al0.1Ga0.9N QDs was investigated, by varying the Al0.1Ga0.9N amount deposited. An increase of the transition energy (from 3.65 eV up to 3.83 eV) is obtained while decreasing the deposited amount. Calculations of the ground state transition energies as a function of the Al0.1Ga0.9N dot height give a value of Fint around 2.0 ± 0.5 MV/cm. Therefore, the propensity of Al0.1Ga0.9N dots to emit at much higher energies than GaN dots (a PL shift of ˜1 eV using a low excitation power) is seen as the consequence of the reduced Fint together with their smaller sizes.

  4. Support for Marijuana Legalization and Predictors of Intentions to Use Marijuana More Often in Response to Legalization Among U.S. Young Adults.

    PubMed

    Cohn, Amy M; Johnson, Amanda L; Rose, Shyanika W; Rath, Jessica M; Villanti, Andrea C

    2017-01-28

    As of 2015, more than half of U.S. states have legalized, medicalized, or decriminalized marijuana. This study examined the prevalence and correlates of support for marijuana legalization in a national sample of young adults and the intention to use marijuana more frequently if it were legalized. Data were from Wave 7 (weighted N = 3532) of the Truth Initiative Young Adult Cohort, a national sample of men and women aged 18-34. We assessed demographics, past 30-day substance (alcohol, tobacco, marijuana, other drug use), depression and anxiety, social smoking, marijuana harm perceptions (relative to cigarettes), and state-level marijuana policies as correlates of support for marijuana legalization and intentions to use marijuana more often if it were legalized. Multivariable models of correlates of support for legalization and intentions to use marijuana were conducted separately for the full sample and for nonmarijuana users. Weighted estimates showed that 39% of the full sample and 9% of nonmarijuana users supported marijuana legalization. Multivariable models showed that lower marijuana harm perceptions and lifetime and past 30-day tobacco use were common predictors of support for marijuana legalization and intentions to use marijuana among non-users of marijuana. Conclusions/Importance: Over a third of the sample supported marijuana legalization. Tobacco use and perceptions that marijuana is less harmful than cigarettes were robust risk correlates of support for marijuana legalization and intentions to use more frequently among nonusers. Public health campaigns should target these factors to deter marijuana-related harm in susceptible young adults.

  5. 7 CFR 801.9 - Tolerances for test weight apparatuses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.9 Tolerances for test weight apparatuses. The maintenance tolerances for test weight per bushel apparatuses used in performing official inspection services... 7 Agriculture 7 2011-01-01 2011-01-01 false Tolerances for test weight apparatuses. 801.9 Section...

  6. 7 CFR 801.9 - Tolerances for test weight apparatuses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.9 Tolerances for test weight apparatuses. The maintenance tolerances for test weight per bushel apparatuses used in performing official inspection services... 7 Agriculture 7 2010-01-01 2010-01-01 false Tolerances for test weight apparatuses. 801.9 Section...

  7. Neutron diffraction study of antiferromagnetic ErNi3Ga9 in magnetic fields

    NASA Astrophysics Data System (ADS)

    Ninomiya, Hiroki; Sato, Takaaki; Matsumoto, Yuji; Moyoshi, Taketo; Nakao, Akiko; Ohishi, Kazuki; Kousaka, Yusuke; Akimitsu, Jun; Inoue, Katsuya; Ohara, Shigeo

    2018-05-01

    We report specific heat, magnetization, magnetoresistance, and neutron diffraction measurements of single crystals of ErNi3Ga9. This compound crystalizes in a chiral structure with space group R 32 . The erbium ions form a two-dimensional honeycomb structure. ErNi3Ga9 displays antiferromagnetic order below 6.4 K. We determined that the magnetic structure is slightly amplitude-modulated as well as antiferromagnetic with q = (0 , 0 , 0.5) . The magnetic properties are described by an Ising-like model in which the magnetic moment is always along the c-axis owing to the large uniaxial anisotropy caused by the crystalline electric field effect in the low temperature region. When the magnetic field is applied along the c-axis, a metamagnetic transition is observed around 12 kOe at 2 K. ErNi3Ga9 possesses crystal chirality, but the antisymmetric magnetic interaction, the so-called Dzyaloshinskii-Moriya (DM) interaction, does not contribute to the magnetic structure, because the magnetic moments are parallel to the DM-vector.

  8. (68)Ga-DOTA-Siglec-9 PET/CT imaging of peri-implant tissue responses and staphylococcal infections.

    PubMed

    Ahtinen, Helena; Kulkova, Julia; Lindholm, Laura; Eerola, Erkki; Hakanen, Antti J; Moritz, Niko; Söderström, Mirva; Saanijoki, Tiina; Jalkanen, Sirpa; Roivainen, Anne; Aro, Hannu T

    2014-01-01

    Staphylococcus epidermidis (S. epidermidis) has emerged as one of the leading pathogens of biomaterial-related infections. Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial molecule controlling extravasation of leukocytes. Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1. We hypothesized that (68)Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated Siglec-9 motif containing peptide ((68)Ga-DOTA-Siglec-9) could detect inflammatory response due to S. epidermidis peri-implant infection by positron emission tomography (PET). Thirty Sprague-Dawley rats were randomized into three groups. A sterile catheter was implanted into the medullary canal of the left tibia. In groups 1 and 2, the implantation was followed by peri-implant injection of S. epidermidis or Staphylococcus aureus (S. aureus) with adjunct injections of aqueous sodium morrhuate. In group 3, sterile saline was injected instead of bacteria and no aqueous sodium morrhuate was used. At 2 weeks after operation, (68)Ga-DOTA-Siglec-9 PET coupled with computed tomography (CT) was performed with the measurement of the standardized uptake value (SUV). The presence of the implant-related infection was verified by microbiological analysis, imaging with fluorescence microscope, and histology. The in vivo PET results were verified by ex vivo measurements by gamma counter. In group 3, the tibias with implanted sterile catheters showed an increased local uptake of (68)Ga-DOTA-Siglec-9 compared with the intact contralateral bones (SUVratio +29.5%). (68)Ga-DOTA-Siglec-9 PET detected inflammation induced by S. epidermidis and S. aureus catheter-related bone infections (SUVratio +58.1% and +41.7%, respectively). The tracer uptake was significantly higher in the S. epidermidis group than in group 3 without bacterial inoculation, but the difference between S. epidermidis and S. aureus groups was not statistically significant. The

  9. 68Ga-DOTA-Siglec-9 PET/CT imaging of peri-implant tissue responses and staphylococcal infections

    PubMed Central

    2014-01-01

    Background Staphylococcus epidermidis (S. epidermidis) has emerged as one of the leading pathogens of biomaterial-related infections. Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial molecule controlling extravasation of leukocytes. Sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1. We hypothesized that 68Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated Siglec-9 motif containing peptide (68Ga-DOTA-Siglec-9) could detect inflammatory response due to S. epidermidis peri-implant infection by positron emission tomography (PET). Methods Thirty Sprague-Dawley rats were randomized into three groups. A sterile catheter was implanted into the medullary canal of the left tibia. In groups 1 and 2, the implantation was followed by peri-implant injection of S. epidermidis or Staphylococcus aureus (S. aureus) with adjunct injections of aqueous sodium morrhuate. In group 3, sterile saline was injected instead of bacteria and no aqueous sodium morrhuate was used. At 2 weeks after operation, 68Ga-DOTA-Siglec-9 PET coupled with computed tomography (CT) was performed with the measurement of the standardized uptake value (SUV). The presence of the implant-related infection was verified by microbiological analysis, imaging with fluorescence microscope, and histology. The in vivo PET results were verified by ex vivo measurements by gamma counter. Results In group 3, the tibias with implanted sterile catheters showed an increased local uptake of 68Ga-DOTA-Siglec-9 compared with the intact contralateral bones (SUVratio +29.5%). 68Ga-DOTA-Siglec-9 PET detected inflammation induced by S. epidermidis and S. aureus catheter-related bone infections (SUVratio +58.1% and +41.7%, respectively). The tracer uptake was significantly higher in the S. epidermidis group than in group 3 without bacterial inoculation, but the difference between S. epidermidis and S. aureus groups was not statistically

  10. Local ordering and magnetism in Ga{sub 0.9}Fe{sub 3.1}N

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

    Burghaus, Jens; Sougrati, Moulay T., E-mail: moulay-tahar.sougrati@univ-montp2.fr; Moechel, Anne

    Prior investigations of the ternary nitride series Ga{sub 1-x}Fe{sub 3+x}N (0{<=}x{<=}1) have indicated a transition from ferromagnetic {gamma}'-Fe{sub 4}N to antiferromagnetic 'GaFe{sub 3}N'. The ternary nitride 'GaFe{sub 3}N' has been magnetically and spectroscopically reinvestigated in order to explore the weakening of the ferromagnetic interactions through the gradual incorporation of gallium into {gamma}'-Fe{sub 4}N. A hysteretic loop at RT reveals the presence of a minority phase of only 0.1-0.2 at%, in accord with the sound two-step synthesis. The composition of the gallium-richest phase 'GaFe{sub 3}N' was clarified by Prompt Gamma-ray Activation Analysis and leads to the berthollide formula Ga{sub 0.91(1)}Fe{sub 3.09(10)}N{submore » 1.05(7)}. Magnetic measurements indicate a transition around 8 K, further supported by Moessbauer spectral data. The weakening of the ferromagnetic coupling through an increasing gallium concentration is explained by a simple Stoner argument. In Ga{sub 0.9}Fe{sub 3.1}N, the presence of iron on the gallium site affects the magnetism by the formation of 13-atom iron clusters. - Graphical Abstract: The crystal structure of GaFe{sub 3}N with green nitrogen atoms in the very center, red iron atoms at the face centers, and gray gallium atoms at the corner positions. Highlights: > Almost phase-pure synthesis of Ga{sub 0.9}Fe{sub 3.1}N. > Prompt gamma-ray activation analysis yields precise composition. > Magnetic ordering of the facial Fe atoms at the lowest temperatures. > Moessbauer spectroscopy suggests percolation or RKKY-type interaction. > Fe{sub 13} clusters due to berthollide character.« less

  11. Analysis of the Structures and Properties of (GaSb)n (n = 4-9) Clusters through Density Functional Theory.

    PubMed

    Lu, Qi Liang; Luo, Qi Quan; Huang, Shou Guo; Li, Yi De; Wan, Jian Guo

    2016-07-07

    An optimization strategy combining global semiempirical quantum mechanical search with all-electron density functional theory was adopted to determine the lowest energy structure of (GaSb)n clusters up to n = 9. The growth pattern of the clusters differed from those of previously reported group III-V binary clusters. A cagelike configuration was found for cluster sizes n ≤ 7. The structure of (GaSb)6 deviated from that of other III-V clusters. Competition existed between core-shell and hollow cage structures of (GaSb)7. Novel noncagelike structures were energetically preferred over the cages for the (GaSb)8 and (GaSb)9 clusters. Electronic properties, such as vertical ionization potential, adiabatic electron affinities, HOMO-LUMO gaps, and average on-site charges on Ga or Sb atoms, as well as binding energies, were computed.

  12. Implicit Weight Bias in Children Age 9 to 11 Years.

    PubMed

    Skinner, Asheley Cockrell; Payne, Keith; Perrin, Andrew J; Panter, Abigail T; Howard, Janna B; Bardone-Cone, Anna; Bulik, Cynthia M; Steiner, Michael J; Perrin, Eliana M

    2017-07-01

    Assess implicit weight bias in children 9 to 11 years old. Implicit weight bias was measured in children ages 9 to 11 ( N = 114) by using the Affect Misattribution Procedure. Participants were shown a test image of a child for 350 milliseconds followed by a meaningless fractal (200 milliseconds), and then they were asked to rate the fractal image as "good" or "bad." We used 9 image pairs matched on age, race, sex, and activity but differing by weight of the child. Implicit bias was the difference between positive ratings for fractals preceded by an image of a healthy-weight child and positive ratings for fractals preceded by an image of an overweight child. On average, 64% of abstract fractals shown after pictures of healthy-weight children were rated as "good," compared with 59% of those shown after pictures of overweight children, reflecting an overall implicit bias rate of 5.4% against overweight children ( P < .001). Healthy-weight participants showed greater implicit bias than over- and underweight participants (7.9%, 1.4%, and 0.3% respectively; P = .049). Implicit bias toward overweight individuals is evident in children aged 9 to 11 years with a magnitude of implicit bias (5.4%) similar to that in studies of implicit racial bias among adults. Copyright © 2017 by the American Academy of Pediatrics.

  13. Quaternary non-centrosymmetric sulfide Y4GaSbS9: Syntheses, structures, optical properties and theoretical studies

    NASA Astrophysics Data System (ADS)

    Wang, Yue; Zou, Xiaochuan; Feng, Xia; Shi, Yongfang; Wu, Liming

    2017-01-01

    A new rare-earth metal gallium thioantimonate, Y4GaSbS9, has been synthesized successfully via high-temperature solid-state method. Single-crystal X-ray diffraction analyses revealed it adopted a known RE4GaSbS9-structure type in the orthorhombic space group Aba2 (no.41) with a=13.480(4) Å, b=13.790(4) Å, c=13.990(4) Å, V=2600.6(2) Å3 and Z=8. The structure is composed of bimetallic polar (Sb2S5) units and dimeric (GaS4)2 tetrahedra that share vertexes to form a 1D infinite chains 2 ∞ 1Ga 10-, inside which the isolated Y3+ cations and S2- anions. Polycrystalline Y4GaSbS9 shows the weak powder second harmonic generation (SHG) responses of this family, which is about 7.5 times that of the benchmark α-SiO2 in the particle size of 74-106 μm at the laser radiation wavelength of 2050 nm with a non-phase-matchable behavior. In addition, the synthesis, structural characterization, and optical properties as well as theoretical studies are also discussed.

  14. 5 CFR 1604.9 - Court orders and legal processes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., annulment, or legal separation, and is subject to legal process relating to child support, alimony, or child abuse. The TSP will make a payment from a service member's account under such orders or processes as...

  15. 5 CFR 1604.9 - Court orders and legal processes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., annulment, or legal separation, and is subject to legal process relating to child support, alimony, or child abuse. The TSP will make a payment from a service member's account under such orders or processes as...

  16. Centrosymmetry vs noncentrosymmetry in La2Ga0.33SbS5 and Ce4GaSbS9 based on the interesting size effects of lanthanides: Syntheses, crystal structures, and optical properties

    NASA Astrophysics Data System (ADS)

    Zhao, Hua-Jun

    2016-05-01

    Two new quaternary sulfides La2Ga0.33SbS5 and Ce4GaSbS9 have been prepared from stoichiometric elements at 1223 K in an evacuated silica tube. Interestingly, La2Ga0.33SbS5 crystallizes in the centrosymmetric structure, while Ce4GaSbS9 crystallizes in the noncentrosymmetric structure, which show obvious size effects of lanthanides on the crystal structures of these two compounds. Ce4GaSbS9 belongs to RE4GaSbS9 (RE=Pr, Nd, Sm, Gd-Ho) structure type with a=13.8834(9) Å, b=14.3004(11) Å, c=14.4102(13) Å, V=2861.0(4) Å3. The structure features infinite chains of [Ga2Sb2S1110-]∞ propagating along a direction separated by Ce3+ cations and S2- anions. La2Ga0.33SbS5 adopts the family of La4FeSb2S10-related structure with a=7.5193(6) Å, c=13.4126(17) Å, V=758.35(13) Å3. Its structure is built up from the alternate stacking of La/Sb/S and La/Ga/S 2D building blocks. The La/Sb/S slabs consist of teeter-totter chains of Sb1S4 seesaws, which are connected via sharing the apexes of μ4-S1. Moreover, La1 is positionally disordered with Sb1 and stabilized in a bicapped trigonal prismatic coordination sphere. Between these La/Sb/S slabs, La2S8 square antiprisms are connected via edge-sharing into 2D building blocks, creating tetrahedral sites partially occupied by the Ga1 atoms. UV/Vis diffuse reflectance spectroscopy study shows that the optical gap of La2Ga0.33SbS5 is about 1.76 eV.

  17. Enhancement of P3HT organic photodiodes by the addition of a GaSe9 alloy thin layer

    NASA Astrophysics Data System (ADS)

    Siqueira, M. C.; Hoff, A.; de, C., Col; Machado, K. D.; Hümmelgen, I. A.; Serbena, J. P. M.

    2017-08-01

    We report on gallium-selenium alloy (GaSe9) thin films simultaneously functioning as both blocking layer and active layer on poly(3-hexylthiophene-2, 5-diyl) (P3HT)-based organic photodiodes in order to enhance device performance. In addition to improved transport of the photogenerated charge carriers, GaSe9 films also contribute to light absorption on a different wavelength interval than that of P3HT. Three different devices are compared: ITO/GaSe9/Al, ITO/P3HT/Al and ITO/P3HT/GaSe9/Al, with the last one presenting a lower dark current density (0.90 μA cm-2), higher ON/OFF current ratio (61) and fastest response under AM 1.5 light irradiance. The observed responsivity is 7.3 mA W-1 and is almost linearly dependent on irradiance in the range 0.6-60 W m-2. A maximum external quantum efficiency of 135% and specific detectivity of 16.7 × 1011 Jones at 390 nm incident light wavelength are obtained.

  18. (67/68)Ga-labeling agent that liberates (67/68)Ga-NOTA-methionine by lysosomal proteolysis of parental low molecular weight polypeptides to reduce renal radioactivity levels.

    PubMed

    Uehara, Tomoya; Rokugawa, Takemi; Kinoshita, Mai; Nemoto, Souki; Fransisco Lazaro, Guerra Gomez; Hanaoka, Hirofumi; Arano, Yasushi

    2014-11-19

    The renal localization of gallium-67 or gallium-68 ((67/68)Ga)-labeled low molecular weight (LMW) probes such as peptides and antibody fragments constitutes a problem in targeted imaging. Wu et al. previously showed that (67)Ga-labeled S-2-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (SCN-Bz-NOTA)-conjugated methionine ((67)Ga-NOTA-Met) was rapidly excreted from the kidney in urine following lysosomal proteolysis of the parental (67)Ga-NOTA-Bz-SCN-disulfide-stabilized Fv fragment (Bioconjugate Chem., (1997) 8, 365-369). In the present study, a new (67/68)Ga-labeling reagent for LMW probes that liberates (67/68)Ga-NOTA-Met was designed, synthesized, and evaluated using longer-lived (67)Ga in order to reduce renal radioactivity levels. We employed a methionine-isoleucine (MI) dipeptide bond as the cleavable linkage. The amine residue of MI was coupled with SCN-Bz-NOTA for (67)Ga-labeling, while the carboxylic acid residue of MI was derivatized to maleimide for antibody conjugation in order to synthesize NOTA-MI-Mal. A Fab fragment of the anti-Her2 antibody was thiolated with iminothiolane, and NOTA-MI-Mal was conjugated with the antibody fragment by maleimide-thiol chemistry. The Fab fragment was also conjugated with SCN-Bz-NOTA (NOTA-Fab) for comparison. (67)Ga-NOTA-MI-Fab was obtained at radiochemical yields of over 95% and was stable in murine serum for 24 h. In the biodistribution study using normal mice, (67)Ga-NOTA-MI-Fab registered significantly lower renal radioactivity levels from 1 to 6 h postinjection than those of (67)Ga-NOTA-Fab. An analysis of urine samples obtained 6 h after the injection of (67)Ga-NOTA-MI-Fab showed that the majority of radioactivity was excreted as (67)Ga-NOTA-Met. In the biodistribution study using tumor-bearing mice, the tumor to kidney ratios of (67)Ga-NOTA-MI-Fab were 4 times higher (6 h postinjection) than those of (67)Ga-NOTA-Fab. Although further studies including the structure of radiometabolites and

  19. Pb-isotopic systematics of lunar highland rocks (>3.9 Ga): Constraints on early lunar evolution

    USGS Publications Warehouse

    Premo, W.R.; Tatsumoto, M.; Misawa, K.; Nakamuka, N.; Kita, N.I.

    1999-01-01

    The present lead (Pb)-isotopic database of over 200 analyses from nearly 90 samples of non-mare basalt, lunar highland rocks (>3.9 Ga) delineate at least three isotopically distinct signatures that in some combination can be interpreted to characterize the systematics of the entire database. Two are fairly new sets of lunar data and are typical of Pb data from other solar-system objects, describing nearly linear arrays slightly above the 'geochron' values, with 207Pb/206Pb values 500). Although the age and origin of this exotic Pb is not well constrained, it is interpreted to be related to the entrapment of incompatible-element-rich (U, Th) melts within the lunar upper mantle and crust between 4.36 and 4.46 Ga (urKREEP residuum?). The latest discovered Pb signature is found only in lunar meteorites and is characterized by relatively low source ?? values between 10 and 50 at 3.9 Ga. The fact that most lunar crustal rocks (>3.9 Ga) exhibit high 207Pb/206Pb values requires that they were derived from, mixed with, or contaminated by Pb produced from early-formed, high-?? sources. The ubiquity of these U-Pb characteristics in the sample collection is probably an artifact of Apollo and Luna sampling sites, all located on the near side of the Moon, which was deeply excavated during the basin-forming event(s). However, the newest Pb-isotopic data support the idea that the Moon originally had a ?? value of ~8 to 35, slightly elevated from Earth values, and that progressive U-Pb fractionations occurred within the Moon during later stages of differentiation between 4.36 and 4.46 Ga.

  20. 808nm high-power high-efficiency GaAsP/GaInP laser bars

    NASA Astrophysics Data System (ADS)

    Wang, Ye; Yang, Ye; Qin, Li; Wang, Chao; Yao, Di; Liu, Yun; Wang, Lijun

    2008-11-01

    808nm high power diode lasers, which is rapidly maturing technology technically and commercially since the introduction in 1999 of complete kilowatt-scale diode laser systems, have important applications in the fields of industry and pumping solid-state lasers (DPSSL). High power and high power conversion efficiency are extremely important in diode lasers, and they could lead to new applications where space, weight and electrical power are critical. High efficiency devices generate less waste heat, which means less strain on the cooling system and more tolerance to thermal conductivity variation, a lower junction temperature and longer lifetimes. Diode lasers with Al-free materials have superior power conversion efficiency compared with conventional AlGaAs/GaAs devices because of their lower differential series resistance and higher thermal conductivity. 808nm GaAsP/GaInP broad-waveguide emitting diode laser bars with 1mm cavity length have been fabricated. The peak power can reach to 100.9W at 106.5A at quasicontinuous wave operation (200μs, 1000Hz). The maximum power conversion efficiency is 57.38%. Based on these high power laser bars, we fabricate a 1x3 arrays, the maximum power is 64.3W in continuous wave mode when the current is 25.0A. And the threshold current is 5.9A, the slope efficiency is 3.37 W/A.

  1. Low birth weight,very low birth weight rates and gestational age-specific birth weight distribution of korean newborn infants.

    PubMed

    Shin, Son-Moon; Chang, Young-Pyo; Lee, Eun-Sil; Lee, Young-Ah; Son, Dong-Woo; Kim, Min-Hee; Choi, Young-Ryoon

    2005-04-01

    To obtain the low birth weight (LBW) rate, the very low birth weight (VLBW) rate, and gestational age (GA)-specific birth weight distribution based on a large population in Korea, we collected and analyzed the birth data of 108,486 live births with GA greater than 23 weeks for 1 yr from 1 January to 31 December 2001, from 75 hospitals and clinics located in Korea. These data included birth weight, GA, gender of the infants, delivery type, maternal age, and the presence of multiple pregnancy. The mean birth weight and GA of a crude population are 3,188 +/-518 g and 38.7+/-2.1 weeks, respectively. The LBW and the VLBW rates are 7.2% and 1.4%, respectively. The preterm birth rate (less than 37 completed weeks of gestation) is 8.4% and the very preterm birth rate (less than 32 completed weeks of gestation) is 0.7%. The mean birth weights for female infants, multiple births, and births delivered by cesarean section were lower than those for male, singletons, and births delivered vaginally. The risk of delivering LBW or VLBW infant was higher for the teenagers and the older women (aged 35 yr and more). We have also obtained the percentile distribution of GA-specific birth weight in infants over 23 weeks of gestation.

  2. Interleukin-10 -1082 G/A polymorphism and risk of death or bronchopulmonary dysplasia in ventilated very low birth weight infants.

    PubMed

    Yanamandra, Krishna; Boggs, Peter; Loggins, John; Baier, R John

    2005-05-01

    IL-10 is an anti-inflammatory cytokine that may have a protective role in acute lung injury. IL-10 expression is affected by a single-nucleotide polymorphism (SNP) located at position -1082 (G to A). The A allele is associated with lower IL-10 production. Low IL-10 production has been linked to the development of BPD. Thus, the IL-10 -1082 SNP may be a genetic risk factor for the development of BPD in the premature newborn. The IL-10 -1082 SNP was determined in 294 (235 African American, 56 Caucasian, and 3 Hispanic) mechanically ventilated very low birth weight (VLBW) infants and compared to outcome (death and/or development of BPD). Differences in groups were analyzed using ANOVA (continuous variables) or chi square (proportions). The frequency of the A allele in our population was 0.62. Thirty-nine (13.3%) infants were homozygous GG, 146 (49.7%) were heterozygous GA, and 109 (37.0%) were homozygous AA. There were no significant differences between genotype groups with respect to ethnic origin, gender, need for surfactant replacement therapy, and isolation of Ureaplasma urealyticum or Mycoplasma hominis from tracheal aspirates at birth. However, AA infants were slightly more mature and of greater birth weight than GA infants (26.9 +/- 0.2 weeks vs. 26.3 +/- 0.2 weeks, P < 0.05, and 940 +/- 22 g vs. 882 +/- 18 g, P < 0.05, respectively). There was no significant effect of the IL-10 -1082 SNP on mortality or the development of BPD (O2 on 28 days or 36 weeks postconceptional age). However, when considered together, the IL-10 -1082 AA/GA genotypes (lower IL-10 production) were associated with a trend toward reduction in risk for the combined outcome of BPD or death (18/39 vs. 80/255, respectively; P = 0.068). The incidence of other complications of prematurity (retinopathy of prematurity, intraventricular hemorrhage, or periventricular leukomalacia) was not different between groups. In conclusion, the IL-10 -1082 G/A SNP does not have a major influence on mortality

  3. Do early postnatal body weight changes contribute to neonatal morbidities in the extremely low birth weight infants.

    PubMed

    Verma, R; Shibly, S; Fang, H; Pollack, S

    2015-01-01

    The implications of early postnatal body weight changes (Δbw) in the morbidities related to body fluid metabolism in sick preterm infants in not well investigated. The extremely low birth weight infants (ELBW, birth weight <1000 g) have the highest incidence of such morbidities among all neonates. To determine the relationships between Δbw and neonatal morbidities associated with body fluid metabolism in the ELBW infants. In an observational study, the associations between daily weight changes from birth weight (DΔ bw) and oxygen dependence on postnatal day 28 (BPD28), patent ductus arteriosus (PDA), intraventricular-periventricular hemorrhage (IVH), antenatal steroid (ANS) and gestational age (GA) were evaluated. Maximum weight loss (MΔ bw) was correlated with GA, BPD28 and BPD36 (oxygen dependence on postmenstrual 36 weeks). Pearson's correlation co-efficient and multivariate logistic regressions were performed for analysis. DΔ bw correlated inversely with GA on days 1-8 of life (p <  0.01 for all, 0.06 for DOL 2). DΔ bw was associated with a lower risk of BPD28 on days 6 (OR 0.87, 95% CI 0.76-1), 10 (OR 0.86, 95% CI 0.76-0.98) and 11 (OR 0.87, 95% CI 0.77-0.99); with PDA on days 8-11 (OR ranging between 0.89 to 0.92 for the 4 days, 95% CI 0.83 to 0.99) and with IVH on day 5 (OR 0.93, 95% CI 0.86-1) after controlling for GA. DΔ bw was not identified as risk factor for the tested morbidities. ANS decreased DΔ bw on days 4 (OR 0.88, 95% CI 0.78-1) and 10 (OR 0.9, 95% CI 0.84-1). MΔbw correlated directly with BPD28 (r = 0.3, p = 0.004), which declined after controlling for GA (r = 0.2, p = 0.2). DΔ bw is protective for PDA, BPD28 and IVH, independent of gestational age, whereas, the effects of MΔ bw on BPD are governed by maturation in ELBW infants. ANS decreases DΔbw, which correlates inversely with GA during the first week of life.

  4. Centrosymmetry vs noncentrosymmetry in La{sub 2}Ga{sub 0.33}SbS{sub 5} and Ce{sub 4}GaSbS{sub 9} based on the interesting size effects of lanthanides: Syntheses, crystal structures, and optical properties

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

    Zhao, Hua-Jun, E-mail: cszzl772002@yeah.net; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002

    Two new quaternary sulfides La{sub 2}Ga{sub 0.33}SbS{sub 5} and Ce{sub 4}GaSbS{sub 9} have been prepared from stoichiometric elements at 1223 K in an evacuated silica tube. Interestingly, La{sub 2}Ga{sub 0.33}SbS{sub 5} crystallizes in the centrosymmetric structure, while Ce{sub 4}GaSbS{sub 9} crystallizes in the noncentrosymmetric structure, which show obvious size effects of lanthanides on the crystal structures of these two compounds. Ce{sub 4}GaSbS{sub 9} belongs to RE{sub 4}GaSbS{sub 9} (RE=Pr, Nd, Sm, Gd–Ho) structure type with a=13.8834(9) Å, b=14.3004(11) Å, c=14.4102(13) Å, V=2861.0(4) Å{sup 3}. The structure features infinite chains of [Ga{sub 2}Sb{sub 2}S{sub 11}{sup 10–}]{sub ∞} propagating along a directionmore » separated by Ce{sup 3+} cations and S{sup 2−} anions. La{sub 2}Ga{sub 0.33}SbS{sub 5} adopts the family of La{sub 4}FeSb{sub 2}S{sub 10}-related structure with a=7.5193(6) Å, c=13.4126(17) Å, V=758.35(13) Å{sup 3}. Its structure is built up from the alternate stacking of La/Sb/S and La/Ga/S 2D building blocks. The La/Sb/S slabs consist of teeter-totter chains of Sb1S{sub 4} seesaws, which are connected via sharing the apexes of μ{sub 4}-S1. Moreover, La1 is positionally disordered with Sb1 and stabilized in a bicapped trigonal prismatic coordination sphere. Between these La/Sb/S slabs, La2S{sub 8} square antiprisms are connected via edge-sharing into 2D building blocks, creating tetrahedral sites partially occupied by the Ga1 atoms. UV/Vis diffuse reflectance spectroscopy study shows that the optical gap of La{sub 2}Ga{sub 0.33}SbS{sub 5} is about 1.76 eV. - Graphical abstract: Two new quaternary sulfides La{sub 2}Ga{sub 0.33}SbS{sub 5} and Ce{sub 4}GaSbS{sub 9} have been prepared by solid-state reactions. Ce{sub 4}GaSbS{sub 9} crystallizes in RE{sub 4}GaSbS{sub 9} (RE=Pr, Nd, Sm, Gd–Ho) structure type, while La{sub 2}Ga{sub 0.33}SbS{sub 5} belongs to the family of La{sub 4}FeSb{sub 2}S{sub 10}-related structure and

  5. Recessed Slant Gate AlGaN/GaN High Electron Mobility Transistors with 20.9 W/mm at 10 GHz

    NASA Astrophysics Data System (ADS)

    Pei, Yi; Chu, Rongming; Fichtenbaum, Nicholas A.; Chen, Zhen; Brown, David; Shen, Likun; Keller, Stacia; DenBaars, Steven P.; Mishra, Umesh K.

    2007-12-01

    A recessed slant gate processing has been used in AlGaN/GaN high electron mobility transistors (HEMTs) to mitigate the electric field, minimize the dispersion and increase the breakdown voltage. More than one order of magnitude of decrease in gate leakage has been observed by recessing the slant gate. For a 0.65 μm gate-length device, an extrinsic fT of 18 GHz and extrinsic fMAX of 52 GHz at a drain bias of 25 V were achieved. At 10 GHz, a state-of-the-art power density of 20.9 W/mm, with a power-added efficiency (PAE) of 40% at a drain bias of 83 V, was demonstrated.

  6. A Change in Igneous Activity of the Jack Hills Zircon Sources ca. 3.9 Ga

    NASA Astrophysics Data System (ADS)

    Bell, E. A.; Harrison, T. M.

    2010-12-01

    New Ti-in-zircon crystallization temperature (Txlln) data for <4 Ga Jack Hills zircons reveal that the tight clustering of Hadean grains around a Txlln of 680°C, possibly indicative of felsic-to-intermediate minimum melting conditions, continues to ~3.92 Ga. Between 3.92-3.82 Ga the 680°C clustering ceases and most concordant grains cluster around an apparent Txlln of 610°C. A small group of zircons with higher Txlln (~750°C), present during the Hadean, is also observed during this period. After 3.82 Ga a Hadean-like distribution resumes for ~100 Ma. This large, concordant, low-Ti group at ~3.9 Ga is statistically distinct from the Hadean distribution and appears to be unique in the Jack Hills zircon record. The existence of coeval high- and low-Ti groups suggests that two distinct zircon-forming processes are distinguishable ~3.9 Ga, unlike during the Hadean. The significant numbers of zircons with apparent Txlln below 600°C may be suggestive of subsolidus formation, since igneous units with solidii below 600°C are relatively rare. The higher-Ti group is more consistent with an intermediate to mafic igneous origin but metamorphic overprinting or subsolidus formation at granulite grade cannot be ruled out by Txlln alone. A substantial proportion of the high-Ti group display oscillatory and disrupted oscillatory zoning in cathodoluminescence images, usually indicative of igneous origins and later metamorphism, respectively; most low-Ti grains are homogeneous. Several of each group display patchy zonation indicative of metamorphic overprinting. Although several grains with apparent Txlln >600°C display oscillatory zonation, the majority of the low-Ti group do not show textural evidence for igneous origins. We interpret these results to indicate the transition from a mechanism(s) that produced dominantly 680°C apparent zircon temperatures at ca. 3.9 Ga to include a new zircon-forming process in the sediment source(s), likely a protracted period of metamorphism

  7. 2.9-1.9 Ga paleoalterations of Archean granitic basement of the Franceville basin (Gabon)

    NASA Astrophysics Data System (ADS)

    Mouélé, Idalina Moubiya; Dudoignon, Patrick; El Albani, Abderrazak; Meunier, Alain; Boulvais, Philippe; Gauthier-Lafaye, François; Paquette, Jean-Louis; Martin, Hervé; Cuney, Michel

    2014-09-01

    The Archean granitoids in the Kiéné area, Gabon, are overlained by the Paleoproterozoic sediments of the Franceville basin (2.1 Ga). The basin is known for its high-grade uranium deposits among which some have been forming natural nuclear fission reactors. Most of the studies were dedicated to the FA-FB Paleoproterozoic sediments hosting these uranium deposits. Little is known on the Archean basement itself and specifically on the hydrous alteration events it experienced before and after the sediment deposition. The present work is focused on their petrographical, mineralogical and geochemical characterization. Dating the successive alteration events has been attempted on altered monazite crystals. Rocks in different alteration states have been sampled from eight drill cores crosscutting the Archean - Paleoproterozoic unconformity. The Archean granitoids observed in the deepest levels exhibit typical petrographical features of a propylitic alteration while they are intensely illitized up to the unconformity. The propylitic alteration is mainly pervasive but the original texture of the granitoïds is conserved in spite of the formation of new minerals: Mg-chlorite, allanite and epidote forming a typical paragenesis. The illitic alteration is much more invasive near the unconformity. The illitization process leads to the replacement of feldspars and the corrosion of quartz crysals by an illitic matrix while the ferromagnesian minerals are pseudomorphosed by a Fe-chlorite + phengite + hematite assemblage. The final fluid-rock interaction step is marked by fissural deposits of calcite and anhydrite. The δ13C isotopic data show that the fissural carbonates precipitated from diagenetic fluids enriched carbon products deriving from the maturation of organic matter. The U-Pb isotopic analyzes performed on monazite crystals have dated three distinct events: 3.0-2.9 Ga (magmatic), 2.6 Ga (propylitic alteration) and 1.9 Ga (diagenetic illitization). The calculation of

  8. High efficiency epitaxial GaAs/GaAs and GaAs/Ge solar cell technology using OM/CVD

    NASA Technical Reports Server (NTRS)

    Wang, K. L.; Yeh, Y. C. M.; Stirn, R. J.; Swerdling, S.

    1980-01-01

    A technology for fabricating high efficiency, thin film GaAs solar cells on substrates appropriate for space and/or terrestrial applications was developed. The approach adopted utilizes organometallic chemical vapor deposition (OM-CVD) to form a GaAs layer epitaxially on a suitably prepared Ge epi-interlayer deposited on a substrate, especially a light weight silicon substrate which can lead to a 300 watt per kilogram array technology for space. The proposed cell structure is described. The GaAs epilayer growth on single crystal GaAs and Ge wafer substrates were investigated.

  9. An argyrodite-type Ag9GaSe6 liquid-like material with ultralow thermal conductivity and high thermoelectric performance.

    PubMed

    Jiang, Binbin; Qiu, Pengfei; Chen, Hongyi; Zhang, Qihao; Zhao, Kunpeng; Ren, Dudi; Shi, Xun; Chen, Lidong

    2017-10-24

    We report a ternary argyrodite-type Ag 9 GaSe 6 compound as a promising thermoelectric material in a moderate temperature range. Due to high carrier mobility and ultralow lattice thermal conductivity, a maximum ZT of 1.1 was obtained with stoichiometric Ag 9 GaSe 6 at 800 K. Via introducing slight Se-deficiency to optimize the carrier concentration, the maximum ZT is further enhanced to 1.3.

  10. Na8Au9.8(4)Ga7.2 and Na17Au5.87(2)Ga46.63: The diversity of pseudo 5-fold symmetries in the Na-Au-Ga system

    NASA Astrophysics Data System (ADS)

    Smetana, Volodymyr; Corbett, John D.; Miller, Gordon J.

    2013-11-01

    The Na-rich part (~30% Na) of the Na-Au-Ga system between NaAu2, NaGa4, and Na22Ga39 has been found to contain the ternary phases Na8Au9.8(4)Ga7.2 (I) and Na17Au5.87(2)Ga46.63 (II), according to the results of single crystal X-ray diffraction measurements. I is orthorhombic, Cmcm, a=5.3040(1), b=24.519(5), c=14.573(3) Å, and contains a network of clusters with local 5-fold symmetry along the a-axis. Such clusters are frequent building units in decagonal quasicrystals and their approximants. II is rhombohedral, R3¯m, a=16.325(2), c=35.242(7) Å, and contains building blocks that are structurally identical to the Bergman-type clusters as well as fused icosahedral units known with active metals, triels and late transition elements. II also contains a polycationic network with elements of the clathrate V type structure. Tight-binding electronic structure calculations using linear muffin-tin-orbital (LMTO) methods on idealized models of I and II indicate that both compounds are metallic with evident pseudogaps at the corresponding Fermi levels. The overall Hamilton bond populations are generally dominated by Au-Ga and Au-Au bonds in I and by Ga-Ga bonds in II; moreover, the Na-Au and Na-Ga contributions in I are unexpectedly large, ~20% of the total. A similar involvement of sodium in covalent bonding has also been found in the electron-richer i-Na13Au12Ga15 quasicrystal approximant.

  11. [The status of protein intake and energy supply in the early life of very/extremely low birth weight infants].

    PubMed

    Bi, Chun-Yu; Ru, Xi-Fang; Feng, Qi; Wang, Ying; Zhang, Xin; Li, Xing; Meng, Jing-Wen

    2013-05-01

    To study the relationship of protein intake and energy supply with the physical growth in very/extremely low birth weight infant at their early life. Retrospective survey was performed in Neonatal Intensive Care Unit (NICU) in Peking University First Hospital. Inclusion criteria were preterm infant, birth weight < 1500 g, hospitalization for longer than 2 weeks, discharge with body weight greater than 1800 g. The infants were divided into two groups according to gestational age (GA). GA < 32 weeks and ≥ 32 weeks. Physical growth and its relation with the protein intake and energy supply were analyzed. The predictive value of serum blood urea nitrogen (BUN) on protein intake was studied. Ninety-three very/extremely low birth weight infants were involved, 69 in GA < 32 weeks group and 24 in GA ≥ 32 weeks group.Compared with GA ≥ 32 group, GA < 32 weeks preterm infants had more weight loss, (9.2 ± 4.4)% vs. (5.0 ± 3.1)%, P = 0.000; slower birth weight recovery (10.6 ± 3.8) d vs. (7.1 ± 2.6) d, P = 0.000; poorer weight gain at 1, 4, 5 weeks of life, (-4.5 ± 9.3) g/ (kg·d) vs. (3.4 ± 6.9) g/ (kg·d), P = 0.000 , (13.5 ± 7.3) g/ (kg·d) vs. (19.2 ± 4.9) g/ (kg·d), P = 0.001, (14.6 ± 5.6) g/ (kg·d) vs. (18.2 ± 4.5) g/ (kg·d), P = 0.031; less energy supply at 1 to 5 weeks (P value was 0.000,0.000,0.025,0.001,0.008 respectively) and less protein intake at 1, 4, 5 weeks of life (P value was 0.009,0.006,0.032). Extrauterine growth retardation (EUGR) was still predominant in our subjects, 47.8% in GA < 32 weeks group, and 95.8% in GA ≥ 32 weeks group, P = 0.000. The incidence increased greater in GA < 32 weeks infants, 43.5% vs. 20.8%, P = 0.000.The duration of weight loss and mechanical ventilation correlated negatively with weight gain rate, respectively β = -0.591, P = 0.000 and β = -0.281, P = 0.005; the average energy supply and time taken to reach full enteral feeding were factors improving weight gain, respectively β = 0.202, P = 0.021 and

  12. Over-the-Counter and Out-of-Control: Legal Strategies to Protect Youths From Abusing Products for Weight Control

    PubMed Central

    Taylor, Lisa M.; Austin, S. Bryn

    2013-01-01

    Abuse of widely available, over-the-counter drugs and supplements such as laxatives and diet pills for weight control by youths is well documented in the epidemiological literature. Many such products are not medically recommended for healthy weight control or are especially susceptible to abuse, and their misuse can result in serious health consequences. We analyzed the government’s role in regulating these products to protect public health. We examined federal and state regulatory authority, and referred to international examples to inform our analysis. Several legal interventions are indicated to protect youths, including increased warnings and restrictions on access through behind-the-counter placement or age verification. We suggest future directions for governments internationally to address this pervasive public health problem. PMID:23237149

  13. 16 CFR 500.9 - Units of weight or mass, how expressed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Units of weight or mass, how expressed. 500... UNDER SECTION 4 OF THE FAIR PACKAGING AND LABELING ACT § 500.9 Units of weight or mass, how expressed. (a) The term net weight or net mass may be used in stating the net quantity of contents in terms of...

  14. 16 CFR 500.9 - Units of weight or mass, how expressed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Units of weight or mass, how expressed. 500... UNDER SECTION 4 OF THE FAIR PACKAGING AND LABELING ACT § 500.9 Units of weight or mass, how expressed. (a) The term net weight or net mass may be used in stating the net quantity of contents in terms of...

  15. 21 CFR 172.820 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ethylene oxide and water with a mean molecular weight of 200 to 9,500. (2) It contains no more than 0.2 percent total by weight of ethylene and diethylene glycols when tested by the analytical methods... the total ethylene and diethylene glycol content of polyethylene glycols having mean molecular weights...

  16. Understanding oxygen adsorption on 9.375 at. % Ga-stabilized δ-Pu (111) surface: A DFT study

    DOE PAGES

    Hernandez, Sarah C.; Wilkerson, Marianne P.; Huda, Muhammad N.

    2015-08-30

    Plutonium (Pu) metal reacts rapidly in the presence of oxygen (O), resulting in an oxide layer that will eventually have an olive green rust appearance over time. Recent experimental work suggested that the incorporation of gallium (Ga) as an alloying impurity to stabilize the highly symmetric high temperature δ-phase lattice may also provide resistance against corrosion/oxidation of plutonium. In this paper, we modeled a 9.375 at. % Ga stabilized δ-Pu (111) surface and investigated adsorption of atomic O using all-electron density functional theory. Key findings revealed that the O bonded strongly to a Pu-rich threefold hollow fcc site with amore » chemisorption energy of –5.06 eV. Migration of the O atom to a Pu-rich environment was also highly sensitive to the surface chemistry of the Pu–Ga surface; when the initial on-surface O adsorption site included a bond to a nearest neighboring Ga atom, the O atom relaxed to a Ga deficient environment, thus affirming the O preference for Pu. Only one calculated final on-surface O adsorption site included a Ga-O bond, but this chemisorption energy was energetically unfavorable. Chemisorption energies for interstitial adsorption sites that included a Pu or Pu-Ga environment suggested that over-coordination of the O atom was energetically unfavorable as well. Electronic structure properties of the on-surface sites, illustrated by the partial density of states, implied that the Ga 4p states indirectly but strongly influenced the Pu 6d states strongly to hybridize with the O 2p states, while also weakly influenced the Pu 5f states to hybridize with the O 2p states, even though Ga was not participating in bonding with O.« less

  17. Understanding oxygen adsorption on 9.375 at. % Ga-stabilized δ-Pu (111) surface: A DFT study

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

    Hernandez, Sarah C.; Wilkerson, Marianne P.; Huda, Muhammad N.

    Plutonium (Pu) metal reacts rapidly in the presence of oxygen (O), resulting in an oxide layer that will eventually have an olive green rust appearance over time. Recent experimental work suggested that the incorporation of gallium (Ga) as an alloying impurity to stabilize the highly symmetric high temperature δ-phase lattice may also provide resistance against corrosion/oxidation of plutonium. In this paper, we modeled a 9.375 at. % Ga stabilized δ-Pu (111) surface and investigated adsorption of atomic O using all-electron density functional theory. Key findings revealed that the O bonded strongly to a Pu-rich threefold hollow fcc site with amore » chemisorption energy of –5.06 eV. Migration of the O atom to a Pu-rich environment was also highly sensitive to the surface chemistry of the Pu–Ga surface; when the initial on-surface O adsorption site included a bond to a nearest neighboring Ga atom, the O atom relaxed to a Ga deficient environment, thus affirming the O preference for Pu. Only one calculated final on-surface O adsorption site included a Ga-O bond, but this chemisorption energy was energetically unfavorable. Chemisorption energies for interstitial adsorption sites that included a Pu or Pu-Ga environment suggested that over-coordination of the O atom was energetically unfavorable as well. Electronic structure properties of the on-surface sites, illustrated by the partial density of states, implied that the Ga 4p states indirectly but strongly influenced the Pu 6d states strongly to hybridize with the O 2p states, while also weakly influenced the Pu 5f states to hybridize with the O 2p states, even though Ga was not participating in bonding with O.« less

  18. 9 CFR 201.99 - Purchase of livestock by packers on a carcass grade, carcass weight, or carcass grade and weight...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Purchase of livestock by packers on a carcass grade, carcass weight, or carcass grade and weight basis. 201.99 Section 201.99 Animals and Animal... livestock by packers on a carcass grade, carcass weight, or carcass grade and weight basis. (a) Each packer...

  19. 21 CFR 1404.965 - Legal proceedings.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Legal proceedings. 1404.965 Section 1404.965 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.965 Legal proceedings. Legal proceedings means any criminal proceeding or any...

  20. 21 CFR 1404.965 - Legal proceedings.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 9 2014-04-01 2014-04-01 false Legal proceedings. 1404.965 Section 1404.965 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.965 Legal proceedings. Legal proceedings means any criminal proceeding or any...

  1. 21 CFR 1404.965 - Legal proceedings.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Legal proceedings. 1404.965 Section 1404.965 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.965 Legal proceedings. Legal proceedings means any criminal proceeding or any...

  2. 21 CFR 1404.965 - Legal proceedings.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 9 2013-04-01 2013-04-01 false Legal proceedings. 1404.965 Section 1404.965 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.965 Legal proceedings. Legal proceedings means any criminal proceeding or any...

  3. 21 CFR 1404.965 - Legal proceedings.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Legal proceedings. 1404.965 Section 1404.965 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.965 Legal proceedings. Legal proceedings means any criminal proceeding or any...

  4. 40 CFR 62.4623 - Legal authority.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Legal authority. 62.4623 Section 62... Control of Designated Pollutants from Existing Facilities (section 111(d) Plan) § 62.4623 Legal authority... adequate legal authority for the State to make emission data, as correlated with applicable emissions...

  5. 40 CFR 62.4623 - Legal authority.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Legal authority. 62.4623 Section 62... Control of Designated Pollutants from Existing Facilities (section 111(d) Plan) § 62.4623 Legal authority... adequate legal authority for the State to make emission data, as correlated with applicable emissions...

  6. 40 CFR 62.4623 - Legal authority.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Legal authority. 62.4623 Section 62... Control of Designated Pollutants from Existing Facilities (section 111(d) Plan) § 62.4623 Legal authority... adequate legal authority for the State to make emission data, as correlated with applicable emissions...

  7. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... conditions: (a) The additive is an addition polymer of ethylene oxide and water with a mean molecular weight of 200 to 9,500. (b) It contains no more than 0.2 percent total by weight of ethylene and diethylene... ethylene and diethylene glycols if its mean molecular weight is below 350, when tested by the analytical...

  8. Nine demographic factors and their relationship to attitudes toward abortion legalization.

    PubMed

    Mileti, D S; Barnett, L D

    1972-03-01

    The 1967 Gallup Poll on attitudes toward abortion legislation taken for the Population Council was studied by multivariate analysis of 9 demographic factors: age, family income, occupation of household head, race, section of the country, sex, city size, education and religion. The poll was taken in two waves that totaled 6,065 cases (after weighting for a representative sample and elimination of "don't know" and "no answer" responses). The question asked for approval or disapproval of the legalization of abortion for the four "hard" reasons: mother's health, rape, incest, or expected child deformity. The analysis revealed that age, family income, occupation of household head, race, section of the country, and sex did not in themselves have an effect on attitudes towards abortion legalization, though they sometimes were an influence in combination with other variables. Significant statistical correlations were found between approval of abortion legalization and increasing city size and higher educational level. Abortion approval also increases along a religious scale from Jewish-Protestant-Catholic. The most significant theoretical conclusion of the study was that 6 of the 9 factors were not influential on abortion attitudes and the remaining 3 did not have strong predictive-explanatory power as expected. Re-examination of the causes of abortion attitudes is needed.

  9. 40 CFR 62.05 - Legal authority.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Legal authority. 62.05 Section 62.05... PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS General Provisions § 62.05 Legal authority. (a) The Administrator's determination of the absence or inadequacy of legal authority required to be...

  10. 40 CFR 62.05 - Legal authority.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Legal authority. 62.05 Section 62.05... PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS General Provisions § 62.05 Legal authority. (a) The Administrator's determination of the absence or inadequacy of legal authority required to be...

  11. 40 CFR 62.05 - Legal authority.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Legal authority. 62.05 Section 62.05... PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS General Provisions § 62.05 Legal authority. (a) The Administrator's determination of the absence or inadequacy of legal authority required to be...

  12. The role of body weight, fat distribution and weight change in ethnic differences in the 9-year incidence of hypertension.

    PubMed

    Grootveld, Laura R; Van Valkengoed, Irene G M; Peters, Ron J G; Ujcic-Voortman, Joanne K; Brewster, Lizzy M; Stronks, Karien; Snijder, Marieke B

    2014-05-01

    To investigate the role of body composition (body weight, fat distribution and weight change over time) in ethnic differences in the incidence of hypertension in an ethnic Dutch, South Asian Surinamese and African Surinamese background population living in the Netherlands. We included 361 participants without hypertension at baseline (147 ethnic Dutch, 82 South Asian Surinamese, 132 African Surinamese), aged 35-60 years, in whom anthropometric measurements and blood pressures were measured at baseline and after mean 9 years of follow-up. Data were analysed using logistic regression analyses, with hypertension at follow up as a dependent variable. Body weight, fat distribution and weight gain were positively associated with the risk of developing hypertension; these associations did not statistically significantly differ between ethnic groups [odds ratios (ORs), 95% confidence interval (95% CI) per SD: BMI 1.5 (1.2-2.0); waist circumference 1.5 (1.2-1.9); waist to hip ratio (WHR) 1.4 (1.1-1.9), weight gain of 1-2.9 kg/m 1.8 (0.9-3.8)]. As compared with Dutch, a higher incidence of hypertension was found among South Asian Surinamese [OR 2.6 (1.4-4.8)] and in particular among African Surinamese [OR 3.1 (1.76-5.30)]. Among South Asian Surinamese, adjustment for WHR attenuated the OR the most [OR 1.9 (1.0-3.7)]; among African Surinamese, the strongest effect was observed for adjustment by BMI and WHR simultaneously [OR 2.5 (1.4-4.4)]. The ethnic differences in the incidence of hypertension among a middle-aged group with a Dutch, South Asian Surinamese and African Surinamese background were partly explained by body composition. This suggests that other factors may be involved, including genetic factors or unidentified other determinants.

  13. Diffusion of Mg dopant in metal-organic vapor-phase epitaxy grown GaN and AlxGa1-xN

    NASA Astrophysics Data System (ADS)

    Köhler, K.; Gutt, R.; Wiegert, J.; Kirste, L.

    2013-02-01

    Diffusion of the p-type dopant Mg in GaN and AlxGa1-xN which is accompanied by segregation and affected by transient effects in metal-organic vapor-phase epitaxy reactors is investigated. We have grown 110 nm thick Mg doped GaN and Al0.1Ga0.9N layers on top of undoped GaN and Al0.1Ga0.9N layers, respectively, in a temperature range between 925 °C and 1050 °C where we placed special emphasis on the lower temperature limit without diffusion to allow separation of Mg transients, diffusion, and segregation. Hereby, AlxGa1-xN layers enable monitoring of the resolution limit by secondary ion mass spectrometry analyses for the respective samples; therefore, thin AlxGa1-xN marker layers are incorporated in the thick GaN layers. We found an upper limit of 1.25 × 1019 cm-3 for diffusing Mg atoms in both sample types. Owing to the marked influence of Mg segregation in Al0.1Ga0.9N, diffusion is only seen by using a GaN cap on top of the Al0.1Ga0.9N layer sequence. Diffusion in Al0.1Ga0.9N is shown to be increased by about 25%-30% compared to GaN. Post growth annealing experiments under conditions equivalent to those used for growth of the Mg doped samples showed negligible diffusion. Comparing the results to well established findings on other doped III-V compounds, diffusion is explained by an interstitial-substitutional mechanism with a diffusion coefficient, which is concentration dependent. Analysis of the temperature dependent diffusivity revealed an activation energy of 5.0 eV for GaN:Mg and 5.2 eV for Al0.1Ga0.9N:Mg.

  14. Dopant incorporation in Al0.9Ga0.1As0.06Sb0.94 grown by molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Patra, Saroj Kumar; Tran, Thanh-Nam; Vines, Lasse; Kolevatov, Ilia; Monakhov, Edouard; Fimland, Bjørn-Ove

    2017-04-01

    Incorporation of beryllium (Be) and tellurium (Te) dopants in epitaxially grown Al0.9Ga0.1As0.06Sb0.94 layers was investigated. Carrier concentrations and mobilities of the doped layers were obtained from room temperature Hall effect measurements, and dopant densities from secondary ion mass spectrometry depth profiling. An undoped Al0.3Ga0.7As cap layer and side wall passivation were used to reduce oxidation and improve accuracy in Hall effect measurements. The measurements on Be-doped samples revealed high doping efficiency and the carrier concentration varied linearly with dopant density up to the highest Be dopant density of 2.9 × 1019 cm-3, whereas for Te doped samples the doping efficiency was in general low and the carrier concentration saturated for Te-dopant densities above 8.0 × 1018 cm-3. The low doping efficiency in Te-doped Al0.9Ga0.1As0.06Sb0.94 layer was studied by deep-level transient spectroscopy, revealing existence of deep trap levels and related DX-centers which explains the low doping efficiency.

  15. The influence of psychological factors on post-partum weight retention at 9 months.

    PubMed

    Phillips, Joanne; King, Ross; Skouteris, Helen

    2014-11-01

    Post-partum weight retention (PWR) has been identified as a critical pathway for long-term overweight and obesity. In recent years, psychological factors have been demonstrated to play a key role in contributing to and maintaining PWR. Therefore, the aim of this study was to explore the relationship between post-partum psychological distress and PWR at 9 months, after controlling for maternal weight factors, sleep quality, sociocontextual influences, and maternal behaviours. Pregnant women (N = 126) completed a series of questionnaires at multiple time points from early pregnancy until 9 months post-partum. Hierarchical regression indicated that gestational weight gain, shorter duration (6 months or less) of breastfeeding, and post-partum body dissatisfaction at 3 and 6 months are associated with higher PWR at 9 months; stress, depression, and anxiety had minimal influence. Interventions aimed at preventing excessive PWR should specifically target the prevention of body dissatisfaction and excessive weight gain during pregnancy. What is already known on this subject? Post-partum weight retention (PWR) is a critical pathway for long-term overweight and obesity. Causes of PWR are complex and multifactorial. There is increasing evidence that psychological factors play a key role in predicting high PWR. What does this study add? Post-partum body dissatisfaction at 3 and 6 months is associated with PWR at 9 months post-birth. Post-partum depression, stress and anxiety have less influence on PWR at 9 months. Interventions aimed at preventing excessive PWR should target body dissatisfaction. © 2013 The British Psychological Society.

  16. Hidden disorder in the α '→δ transformation of Pu-1.9 at.% Ga

    DOE PAGES

    Jeffries, J. R.; Manley, M. E.; Wall, M. A.; ...

    2012-06-06

    Enthalpy and entropy are thermodynamic quantities critical to determining how and at what temperature a phase transition occurs. At a phase transition, the enthalpy and temperature-weighted entropy differences between two phases are equal (ΔH=TΔS), but there are materials where this balance has not been experimentally or theoretically realized, leading to the idea of hidden order and disorder. In a Pu-1.9 at. % Ga alloy, the δ phase is retained as a metastable state at room temperature, but at low temperatures, the δ phase yields to a mixed-phase microstructure of δ- and α'-Pu. The previously measured sources of entropy associated withmore » the α'→δ transformation fail to sum to the entropy predicted theoretically. We report an experimental measurement of the entropy of the α'→δ transformation that corroborates the theoretical prediction, and implies that only about 65% of the entropy stabilizing the δ phase is accounted for, leaving a missing entropy of about 0.5 k B/atom. Some previously proposed mechanisms for generating entropy are discussed, but none seem capable of providing the necessary disorder to stabilize the δ phase. This hidden disorder represents multiple accessible states per atom within the δ phase of Pu that may not be included in our current understanding of the properties and phase stability of δ-Pu.« less

  17. Technology requirements for GaAs photovoltaic arrays

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J.; Rockey, D.

    1981-01-01

    An analysis based on percent GaAs solar cell weight and cost is performed to assess the utility of this cell for future space missions. It is shown that the GaAs substrate cost and the end-of-life (EOL) advantage the cell can provide over the space qualified silicon solar cell are the dominant factors determining potential use. Examples are presented to show that system level advantages resulting from reduction in solar panel area may warrant the use of GaAs at its current weight and projected initial cost provided the EOL advantage over silicon is at least 20 percent.

  18. Role of Caspase-9 Gene Ex5+32 G>A (rs1052576) Variant in Susceptibility to Primary Brain Tumors.

    PubMed

    Ozdogan, Selcuk; Kafadar, Ali; Yilmaz, Seda Gulec; Timirci-Kahraman, Ozlem; Gormus, Uzay; Isbir, Turgay

    2017-09-01

    This study is the first to evaluate the relationship of caspase-9 (CASP-9) gene polymorphism with the risk for primary brain tumor development. The study group included 43 glioma and 27 meningioma patients and 76 healthy individuals. CASP-9 gene Ex5+32 G>A (rs1052576) polymorphism was analyzed by real-time polymerase chain reaction (RT-PCR). Individuals with the CASP-9 GG genotype had significantly decreased risk of developing a glioma brain tumor (p=0.024). Additionally, the GA genotype was significantly lower in patients with glioma than the control group (p=0.019). A significantly decreased risk of developing glioma was found in the A allele carrier group (p=0.024). However, there was no statistically significant relationship between CASP-9 polymorphism and brain meningioma (p=0.493). CASP-9 (rs1052576) mutant A allele seems to be a protective factor for glioma brain tumor. Future studies with a larger sample size will clarify the possible roles of CASP-9 gene in the etiology and progression of primary brain tumors. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  19. An Intron 9 CYP19 Gene Variant (IVS9+5G>A), Present in an Aromatase-Deficient Girl, Affects Normal Splicing and Is Also Present in Normal Human Steroidogenic Tissues.

    PubMed

    Saraco, Nora; Nesi-Franca, Suzana; Sainz, Romina; Marino, Roxana; Marques-Pereira, Rosana; La Pastina, Julia; Perez Garrido, Natalia; Sandrini, Romolo; Rivarola, Marco Aurelio; de Lacerda, Luiz; Belgorosky, Alicia

    2015-01-01

    Splicing CYP19 gene variants causing aromatase deficiency in 46,XX disorder of sexual development (DSD) patients have been reported in a few cases. A misbalance between normal and aberrant splicing variants was proposed to explain spontaneous pubertal breast development but an incomplete sex maturation progress. The aim of this study was to functionally characterize a novel CYP19A1 intronic homozygote mutation (IVS9+5G>A) in a 46,XX DSD girl presenting spontaneous breast development and primary amenorrhea, and to evaluate similar splicing variant expression in normal steroidogenic tissues. Genomic DNA analysis, splicing prediction programs, splicing assays, and in vitro protein expression and enzyme activity analyses were carried out. CYP19A1 mRNA expression in human steroidogenic tissues was also studied. A novel IVS9+5G>A homozygote mutation was found. In silico analysis predicts the disappearance of the splicing donor site in intron 9, confirmed by patient peripheral leukocyte cP450arom and in vitro studies. Protein analysis showed a shorter and inactive protein. The intron 9 transcript variant was also found in human steroidogenic tissues. The mutation IVS9+5G>A generates a splicing variant that includes intron 9 which is also present in normal human steroidogenic tissues, suggesting that a misbalance between normal and aberrant splicing variants might occur in target tissues, explaining the clinical phenotype in the affected patient. © 2015 S. Karger AG, Basel.

  20. A Rutile Chevron Modulation in Delafossite-Like Ga 3–x In 3 Ti x O 9+x/2

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

    Rickert, Karl; Boullay, Philippe; Malo, Sylvie

    2016-05-02

    The structure solution of the modulated, delafossite-related, orthorhombic Ga 3–xIn 3Ti xO 9+x/2 for x = 1.5 is reported here in conjunction with a model describing the modulation as a function of x for the entire system. Previously reported structures in the related A 3–xIn 3Ti xO 9+x/2 (A = Al, Cr, or Fe) systems use X-ray diffraction to determine that the anion lattice is the source of modulation. Neutron diffraction, with its enhanced sensitivity to light atoms, offers a route to solving the modulation and is used here, in combination with precession electron diffraction tomography (PEDT), to solve themore » structure of Ga 1.5In 3Ti 1.5O 9.75. We construct a model that describes the anion modulation through the formation of rutile chevrons as a function of x. This model accommodates the orthorhombic phase (1.5 ≤ x ≤ 2.1) in the Ga 3-xIn 3Ti xO 9+x/2 system, which transitions to a biphasic mixture (2.2 ≤ x ≤ 2.3) with a monoclinic, delafossite-related phase (2.4 ≤ x ≤ 2.5). The optical band gaps of this system are determined, and are stable at ~3.4 eV before a ~0.4 eV decrease between x = 1.9 and 2.0. After this decrease, stability resumes at ~3.0 eV. Resistance to oxidation and reduction is also presented.« less

  1. Geochemistry of approximately 1.9 Ga sedimentary rocks from northeastern Labrador, Canada

    NASA Technical Reports Server (NTRS)

    Hayashi, K. I.; Fujisawa, H.; Holland, H. D.; Ohmoto, H.

    1997-01-01

    Fifty-eight rock chips from fifteen samples of sedimentary rocks from the Ramah Group (approximately 1.9 Ga) in northeastern Labrador, Canada, were analyzed for major and minor elements, including C and S, to elucidate weathering processes on the Earth's surface about 1.9 Ga ago. The samples come from the Rowsell Harbour, Reddick Bight, and Nullataktok Formations. Two rock series, graywackes-gray shales of the Rowsell Harbour, Reddick Bight and Nullataktok Formations, and black shales of the Nullataktok Formation, are distinguishable on the basis of lithology, mineralogy, and major and trace element chemistry. The black shales show lower concentrations than the graywackes-gray shales in TiO2 (0.3-0.7 wt% vs. 0.7-1.8 wt%), Al2O3 (9.5-20.1 wt% vs. 13.0-25.0 wt%), and sigma Fe (<1 wt% vs. 3.8-13.9 wt% as FeO). Contents of Zr, Th, U, Nb, Ce, Y, Rb, Y, Co, and Ni are also lower in the black shales. The source rocks for the Ramah Group sediments were probably Archean gneisses with compositions similar to those in Labrador and western Greenland. The major element chemistry of source rocks for the Ramah Group sedimentary rocks was estimated from the Al2O3/TiO2 ratios of the sedimentary rocks and the relationship between the major element contents (e.g., SiO2 wt%) and Al2O3/TiO2 ratios of the Archean gneisses. This approach is justified, because the Al/Ti ratios of shales generally retain their source rock values; however, the Zr/Al, Zr/Ti, and Cr/Ni ratios fractionate during the transport of sediments. The measured SiO2 contents of shales in the Ramah Group are generally higher than the estimated SiO2 contents of source rocks by approximately 5 wt%. This correction may also have to be applied when estimating average crustal compositions from shales. Two provenances were recognized for the Ramah Group sediments. Provenance I was comprised mostly of rocks of bimodal compositions, one with SiO2 contents approximately 45 wt% and the other approximately 65 wt%, and was the

  2. CXC ligand 9 response to malaria during pregnancy is associated with low-birth-weight deliveries.

    PubMed

    Dong, Shu; Kurtis, Jonathan D; Pond-Tor, Sunthorn; Kabyemela, Edward; Duffy, Patrick E; Fried, Michal

    2012-09-01

    Placental infection with Plasmodium falciparum is associated with increased levels of proinflammatory cytokines, including tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ), and previous studies have associated increased levels of these cytokines with low birth weight (LBW), especially for malaria-infected primigravidae. To define the contribution of TNF-α and IFN-γ networks to placental-malaria-associated LBW, we measured chemokines induced by TNF-α and IFN-γ and related them to birth weight in a birth cohort of 782 mother-infant pairs residing in an area of P. falciparum holoendemicity in Tanzania. Among primigravidae, levels of CCL2, CXC ligand 9 (CXCL9), and CXCL13 were significantly higher during malaria infection in both the placenta and peripheral blood. Placental CXCL9 and CXCL13 levels were also higher in placental blood from secundigravidae and multigravidae. In multivariate analyses adjusted for known predictors of birth weight, malaria-infected primigravidae with placental CXCL9 levels in the lowest tertile gave birth to babies who weighed 610 g more than babies born to mothers with high CXCL9 levels. CXCL9 expression is induced by IFN-γ, and the strong association between birth weight and placental CXCL9 is consistent with previous observations relating IFN-γ to poor pregnancy outcomes.

  3. Does psychosocial stress explain socioeconomic inequities in 9-year weight gain among young women?

    PubMed

    Ball, Kylie; Schoenaker, Danielle A J M; Mishra, Gita D

    2017-06-01

    This study investigated the contribution of psychosocial stress to mediating inequities in weight gain by educational status in a large cohort of young Australian women over a 9-year follow-up. This observational cohort study used survey data drawn from 4,806 women, aged 22 to 27 years at baseline (2000), participating in the Australian Longitudinal Study on Women's Health, who reported their education level (2000), perceived stress (2003), and weight (2003 and 2012). Using a causal inference framework based on counterfactuals for mediation analysis, we fitted linear or logistic regression models to examine the total effect, decomposed into natural direct and indirect effects via perceived stress, of education level (highest qualification completed: up to year 12/trade or diploma vs. university) on weight change. Women with lower education gained more weight over 9 years (6.1 kg, standard deviation [SD] 9.5) than women with higher education (3.8 kg, SD 7.7; P < 0.0001) and were more likely to be very or extremely stressed. The higher weight gain associated with low education was not mediated through perceived stress (per SD increase, percent mediated: 1.0%). Education-based inequities in weight gain over time were not attributable to greater psychosocial stress among women with lower education levels. © 2017 The Obesity Society.

  4. Adjusted poor weight gain for birth weight and gestational age as a predictor of severe ROP in VLBW infants.

    PubMed

    Aydemir, O; Sarikabadayi, Y U; Aydemir, C; Tunay, Z O; Tok, L; Erdeve, O; Oguz, S S; Uras, N; Dilmen, U

    2011-06-01

    To analyze relative weight gain by 2-week intervals up to 6 weeks after birth in order to predict the development of retinopathy of prematurity (ROP) requiring treatment among very low birth weight (BW) infants. A prospective study including infants with BW ≤1500 g born in a single tertiary intensive care unit over 1-year period was conducted. Body weight measurements were recorded weekly and relative weight gains (g/kg/day) were calculated. The main outcome was development of ROP requiring treatment. Mean BW and gestational age (GA) of the whole cohort were 1165±223 g and 29.3±2.3 weeks, respectively. Relative weight gain at 2 weeks and 4 weeks postnatal age were significantly lower in infants with severe ROP (P=0.041 and P=0.017, respectively). Relative weight gain at 6 weeks was not different between groups. Infants with severe ROP gained 6.7±4 g/kg/day in the first 4 weeks of life, compared with 9.3±4.5 g/kg/day for those with mild or no ROP. After adjusted for BW and GA in logistic regression poor relative weight gain in the first 4 weeks was found to be related to severe ROP (P=0.015). When all the other risk factors significant for severe ROP were included in the logistic regression poor weight gain did not arise as an independent risk factor. Poor postnatal weight gain in the first 4 weeks of life is the end result of several comorbidities rather than being an independent risk factor. Poor weight gain can be an additional predictor of severe ROP in very low BW infants.

  5. 21 CFR 172.820 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ethylene oxide and water with a mean molecular weight of 200 to 9,500. (2) It contains no more than 0.2..., or equivalent) 12 percent in H2O by weight on 60-80 mesh nonacid washed diatomaceous earth... in cylinder equipped with reducing regulator to provide 50 p.s.i.g. to the gas chromatograph...

  6. 21 CFR 172.820 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ethylene oxide and water with a mean molecular weight of 200 to 9,500. (2) It contains no more than 0.2..., or equivalent) 12 percent in H2O by weight on 60-80 mesh nonacid washed diatomaceous earth... in cylinder equipped with reducing regulator to provide 50 p.s.i.g. to the gas chromatograph...

  7. 450-nm GaN laser diode enables high-speed visible light communication with 9-Gbps QAM-OFDM.

    PubMed

    Chi, Yu-Chieh; Hsieh, Dan-Hua; Tsai, Cheng-Ting; Chen, Hsiang-Yu; Kuo, Hao-Chung; Lin, Gong-Ru

    2015-05-18

    A TO-38-can packaged Gallium nitride (GaN) blue laser diode (LD) based free-space visible light communication (VLC) with 64-quadrature amplitude modulation (QAM) and 32-subcarrier orthogonal frequency division multiplexing (OFDM) transmission at 9 Gbps is preliminarily demonstrated over a 5-m free-space link. The 3-dB analog modulation bandwidth of the TO-38-can packaged GaN blue LD biased at 65 mA and controlled at 25°C is only 900 MHz, which can be extended to 1.5 GHz for OFDM encoding after throughput intensity optimization. When delivering the 4-Gbps 16-QAM OFDM data within 1-GHz bandwidth, the error vector magnitude (EVM), signal-to-noise ratio (SNR) and bit-error-rate (BER) of the received data are observed as 8.4%, 22.4 dB and 3.5 × 10(-8), respectively. By increasing the encoded bandwidth to 1.5 GHz, the TO-38-can packaged GaN blue LD enlarges its transmission capacity to 6 Gbps but degrades its transmitted BER to 1.7 × 10(-3). The same transmission capacity of 6 Gbps can also be achieved with a BER of 1 × 10(-6) by encoding 64-QAM OFDM data within 1-GHz bandwidth. Using the 1.5-GHz full bandwidth of the TO-38-can packaged GaN blue LD provides the 64-QAM OFDM transmission up to 9 Gbps, which successfully delivers data with an EVM of 5.1%, an SNR of 22 dB and a BER of 3.6 × 10(-3) passed the forward error correction (FEC) criterion.

  8. AlGaN/GaN high electron mobility transistors with selective area grown p-GaN gates

    NASA Astrophysics Data System (ADS)

    Yuliang, Huang; Lian, Zhang; Zhe, Cheng; Yun, Zhang; Yujie, Ai; Yongbing, Zhao; Hongxi, Lu; Junxi, Wang; Jinmin, Li

    2016-11-01

    We report a selective area growth (SAG) method to define the p-GaN gate of AlGaN/GaN high electron mobility transistors (HEMTs) by metal-organic chemical vapor deposition. Compared with Schottky gate HEMTs, the SAG p-GaN gate HEMTs show more positive threshold voltage (V th) and better gate control ability. The influence of Cp2Mg flux of SAG p-GaN gate on the AlGaN/GaN HEMTs has also been studied. With the increasing Cp2Mg from 0.16 μmol/min to 0.20 μmol/min, the V th raises from -0.67 V to -0.37 V. The maximum transconductance of the SAG HEMT at a drain voltage of 10 V is 113.9 mS/mm while that value of the Schottky HEMT is 51.6 mS/mm. The SAG method paves a promising way for achieving p-GaN gate normally-off AlGaN/GaN HEMTs without dry etching damage. Project supported by the National Natural Sciences Foundation of China (Nos. 61376090, 61306008) and the National High Technology Program of China (No. 2014AA032606).

  9. Ultrafast decay of hot phonons in an AlGaN/AlN/AlGaN/GaN camelback channel

    NASA Astrophysics Data System (ADS)

    Leach, J. H.; Wu, M.; Morkoç, H.; Liberis, J.; Šermukšnis, E.; Ramonas, M.; Matulionis, A.

    2011-11-01

    A bottleneck for heat dissipation from the channel of a GaN-based heterostructure field-effect transistor is treated in terms of the lifetime of nonequilibrium (hot) longitudinal optical phonons, which are responsible for additional scattering of electrons in the voltage-biased quasi-two-dimensional channel. The hot-phonon lifetime is measured for an Al0.33Ga0.67N/AlN/Al0.1Ga0.9N/GaN heterostructure where the mobile electrons are spread in a composite Al0.1Ga0.9N/GaN channel and form a camelback electron density profile at high electric fields. In accordance with plasmon-assisted hot-phonon decay, the parameter of importance for the lifetime is not the total charge in the channel (the electron sheet density) but rather the electron density profile. This is demonstrated by comparing two structures with equal sheet densities (1 × 1013 cm-2), but with different density profiles. The camelback channel profile exhibits a shorter hot-phonon lifetime of ˜270 fs as compared with ˜500 fs reported for a standard Al0.33Ga0.67N/AlN/GaN channel at low supplied power levels. When supplied power is sufficient to heat the electrons > 600 K, ultrafast decay of hot phonons is observed in the case of the composite channel structure. In this case, the electron density profile spreads to form a camelback profile, and hot-phonon lifetime reduces to ˜50 fs.

  10. Effect of the common -866G/A polymorphism of the uncoupling protein 2 gene on weight loss and body composition under sibutramine therapy in an obese Taiwanese population.

    PubMed

    Hsiao, Tun-Jen; Wu, Lawrence Shih-Hsin; Hwang, Yuchi; Huang, Shih-Yi; Lin, Eugene

    2010-04-01

    Sibutramine, a serotonin and norepinephrine reuptake inhibitor, is used as an anti-obesity drug. Several pharmacogenetic studies have shown correlations between sibutramine effects and genetic variants, such as the 825C/T (rs5443) single nucleotide polymorphism (SNP) in the guanine nucleotide binding protein beta polypeptide 3 (GNB3) gene. In this study, our goal was to investigate whether a common SNP, -866G/A (rs659366), in the uncoupling protein 2 (UCP2) gene could influence weight reduction and body composition under sibutramine therapy in an obese Taiwanese population. The study included 131 obese patients, 44 in the placebo group and 87 in the sibutramine group. We assessed the measures of weight loss and body fat reduction at the end of a 12-week treatment period by analysis of covariance (ANCOVA) models using gender, baseline weight, and body fat percentage at baseline as covariates. By comparing the placebo and sibutramine groups with ANCOVA, our data showed a strong effect of sibutramine on weight loss in the combined UCP2 -866 AA + GA genotype groups (p < 0.001). Similarly, a strong effect of sibutramine on body fat percentage loss was found for individuals with the AA or GA genotypes (p < 0.001). In contrast, sibutramine had no significant effect on weight loss (p = 0.063) or body fat percentage loss (p = 0.194) for individuals with the wild-type GG genotype, compared with the placebo group of the same genotype. Moreover, a potential gene-gene interaction between UCP2 and GNB3 was identified by multiple linear regression models for the weight loss (p < 0.001) and for the percent fat loss (p = 0.031) in response to sibutramine. The results suggest that the UCP2 gene may contribute to weight loss and fat change in response to sibutramine therapy in obese Taiwanese patients.

  11. Efficient Ga(As)Sb quantum dot emission in AlGaAs by GaAs intermediate layer

    NASA Astrophysics Data System (ADS)

    Loeber, Thomas Henning; Richter, Johannes; Strassner, Johannes; Heisel, Carina; Kimmle, Christina; Fouckhardt, Henning

    2013-03-01

    Ga(As)Sb quantum dots (QDs) are epitaxially grown in AlGaAs/GaAs in the Stranski-Krastanov mode. In the recent past we achieved Ga(As)Sb QDs in GaAs with an extremely high dot density of 9.8•1010 cm-2 by optimization of growth temperature, Sb/Ga flux pressure ratio, and coverage. Additionally, the QD emission wavelength could be chosen precisely with these growth parameters in the range between 876 and 1035 nm. Here we report a photoluminescence (PL) intensity improvement for the case with AlGaAs barriers. Again growth parameters and layer composition are varied. The aluminium content is varied between 0 and 90%. Reflectance anisotropy spectroscopy (RAS) is used as insitu growth control to determine growth rate, layer thickness, and AlGaAs composition. Ga(As)Sb QDs, directly grown in AlxGa1-xAs emit no PL signal, even with a very low x ≈ 0.1. With additional around 10 nm thin GaAs intermediate layers between the Ga(As)Sb QDs and the AlGaAs barriers PL signals are detected. Samples with 4 QD layers and AlxGa1-xAs/GaAs barriers in between are grown. The thickness and composition of the barriers are changed. Depending on these values PL intensity is more than 4 times as high as in the case with simple GaAs barriers. With these results efficient Ga(As)Sb QD lasers are realized, so far only with pure GaAs barriers. Our index-guided broad area lasers operate continuous-wave (cw) @ 90 K, emit optical powers of more than 2•50 mW and show a differential quantum efficiency of 54% with a threshold current density of 528 A/cm2.

  12. C1q/TNF-Related Protein-9 (CTRP9) Levels Are Associated With Obesity and Decrease Following Weight Loss Surgery

    PubMed Central

    Steele, Kimberley E.; Peterson, Leigh A.; Zeng, Xiange; Jaffe, Andrew E.; Schweitzer, Michael A.; Magnuson, Thomas H.; Wong, G. William

    2016-01-01

    Context: C1q/TNF-related protein-9 (CTRP9) is a novel adipokine that has beneficial metabolic and cardiovascular effects in various animal models. Alterations in circulating CTRP9 have also been observed in patients with cardiovascular disease and diabetes, but little is known about the impact of obesity and bariatric surgery on CTRP9 concentrations. Objective: The aim of this study was to compare CTRP9 levels in obese and lean subjects and to determine whether circulating CTRP9 levels in morbidly obese patients are altered by bariatric surgery. Design, Setting, and Participants: Fifty-nine obese bariatric surgical patients and 62 lean controls were recruited to participate in a cross-sectional study at an academic medical center. The obese patients were further invited to participate in a cohort study, and 21 returned for analysis at 3 and 6 months postsurgery. Intervention: Bariatric surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy) was the intervention for this study. Main Outcome Measures: Fasting serum was obtained from all subjects on entry to the study and was analyzed in the core laboratory for hemoglobin A1c, glucose, aspartate aminotransferase, alanine aminotransferase, total cholesterol, high- and low-density lipoprotein cholesterol, and triglycerides; CTRP9, insulin, adiponectin, and leptin were measured by ELISA. Serum from the patients in the cohort study was also analyzed at 3 and 6 months. Results: Serum CTRP9 was significantly higher in the obese group compared to the lean group. CTRP9 was associated with obesity, even after controlling for age, gender, and ethnicity. Following bariatric surgery, there was a significant decrease in weight at 3 and 6 months postprocedure, accompanied by decreases in CTRP9, hemoglobin A1c and leptin, and an increase in serum adiponectin. Conclusions: CTRP9 levels are elevated in obesity and significantly decrease following weight loss surgery. Our data suggest that CTRP9 may play a compensatory role

  13. First principles calculations of the electronic structure and magnetic properties of Y(Fe,M)9.2 and Y(Fe,M)9.2C (M= Si, Ga, Zr)

    NASA Astrophysics Data System (ADS)

    Tian, Guang; Zha, Liang; Yang, Wenyun; Qiao, Guanyi; Wang, Changsheng; Yang, Yingchang; Yang, Jinbo

    2018-06-01

    The preferential site substitution of the Fe by Si, Ga and Zr in the Y(Fe,M)9.2 and Y(Fe,M)9.2C compounds, and the doping effects on the magnetic properties have been studied by the first-principles calculations. It is found that the doping of the Si or Zr can improve the thermodynamic stability of the 1:9 phase, while the substitution of the Fe by Ga makes it unstable. Si atom tends to enter the 3g crystal site and Zr prefers to occupy the 2e site when Y(Fe,M)9.2 and their carbides are synthesized. Although the substitution of the Fe by Si and Zr will reduce the total magnetic moments of the YFe9.2 and their carbides, the volumetric and the d-band narrowing effects caused by the doping can still modify the electron density distributions of the Fe near the Fermi level, improving the magnetic ordering temperature of the non-carbonated compound YFe9.2. The calculated magnetic ordering temperatures of Y(Fe,M)9.2C decrease with the increasing content of the doping elements M due to the stronger hybridization of the d bands in the carbides. For the rare-earth(RE) iron based intermetallics REFe9.2 with the TbCu7-type structure, it is suggested that Zr is able to stabilize the phase and enhance the magnetic ordering temperature, indicating the possible further application in the field of permanent magnets, which has not been reported before.

  14. Magnetometory of AlGaN/GaN heterostructure wafers

    NASA Astrophysics Data System (ADS)

    Tsubaki, K.; Maeda, N.; Saitoh, T.; Kobayashi, N.

    2005-06-01

    AlGaN/GaN heterostructure wafers are becoming a key technology for next generation cellar-phone telecommunication system because of their potential for high-performance microwave applications. Therefore, the electronic properties of a 2DEG in AlGaN/GaN heterostructures have recently been discussed. In this paper, we performed the extraordinary Hall effect measurement and the SQUID magnetometory of AlGaN/GaN heterostructure wafer at low temperature. The AlGaN/GaN heterostructures were grown by low-pressure metal-organic chemical vapour phase epitaxy on (0001) SiC substrate using AlN buffers. The electron mobility and electron concentration at 4.2 K are 9,540cm2/V s and 6.6 × 1012cm-2, respectively. In the extraordinary Hall effect measurement of AlGaN/GaN heterostructures, the hysteresis of Hall resistance appeared below 4.5 K and disappeared above 4.5 K. On the other hand, the hysteresis of magnetometric data obtained by SQUID magnetometory appears near zero magnetic field when the temperature is lower than 4.5 K. At the temperature larger than 4.5 K, the hysteresis of magnetometric data disappears. And the slopes of magnetometric data with respect to magnetic field become lower as obeying Currie-Weiss law and the Curie temperature TC is 4.5 K. Agreement of TC measured by the extraordinary Hall effect and the SQUID magnetometory implies the ferromagnetism at the AlGaN/GaN heterojunction. However, the conformation of the ferromagnetism of AlGaN/GaN heterostructure is still difficult and the detailed physical mechanism is still unclear.

  15. GaAs shallow-homojunction solar cells

    NASA Technical Reports Server (NTRS)

    Fan, J. C. C.

    1981-01-01

    The feasibility of fabricating space resistant, high efficiency, light weight, low cost GaAs shallow homojunction solar cells for space application is investigated. The material preparation of ultrathin GaAs single crystal layers, and the fabrication of efficient GaAs solar cells on bulk GaAs substrates are discussed. Considerable progress was made in both areas, and conversion efficiency about 16% AMO was obtained using anodic oxide as a single layer antireflection coating. A computer design shows that even better cells can be obtained with double layer antireflection coating. Ultrathin, high efficiency solar cells were obtained from GaAs films prepared by the CLEFT process, with conversion efficiency as high as 17% at AMI from a 10 micrometers thick GaAs film. A organometallic CVD was designed and constructed.

  16. Magnetometory Measurement of AlGaN/GaN 2DEG

    NASA Astrophysics Data System (ADS)

    Tsubaki, K.; Maeda, N.; Saitoh, T.; Kobayashi, N.

    2004-03-01

    AlGaN/GaN heterostructure devices have been attracting much attention because of their potential for high-performance microwave applications. Therefore, the electronic properties of a 2DEG in AlGaN/GaN heterostructures have recently been discussed. In this paper, we performed the magnetometory measurement of AlGaN/GaN 2DEG at low temperature. The AlGaN/GaN heterostructures were grown by low-pressure metal-organic chemical vapour phase epitaxy on (0001) SiC substrate using AlN buffers. The electron mobility and electron concentration at 4.2 K are 9,540 cm^2/Vs and 6.6 × 10^12 cm-2, respectively. When the temperature is lower than 4.5 K the hysteresis of magnetometric data is observed near zero magnetic field. At the temperature larger than 4.5 K, the hysteresis of magnetometric data disappears and the slope of magnetometric data with respect to magnetic field becomes lower as obeying Currie-Weiss law. In general the hysteresis and Currie-Weiss law behavior in magnetometric data imply the possibility of the ferromagnetism, but the conformation of the ferromagnetism of AlGaN/GaN heterostructure is still difficult and the detailed physical mechanism is still unclear.

  17. The CHOP postnatal weight gain, birth weight, and gestational age retinopathy of prematurity risk model.

    PubMed

    Binenbaum, Gil; Ying, Gui-Shuang; Quinn, Graham E; Huang, Jiayan; Dreiseitl, Stephan; Antigua, Jules; Foroughi, Negar; Abbasi, Soraya

    2012-12-01

    To develop a birth weight (BW), gestational age (GA), and postnatal-weight gain retinopathy of prematurity (ROP) prediction model in a cohort of infants meeting current screening guidelines. Multivariate logistic regression was applied retrospectively to data from infants born with BW less than 1501 g or GA of 30 weeks or less at a single Philadelphia hospital between January 1, 2004, and December 31, 2009. In the model, BW, GA, and daily weight gain rate were used repeatedly each week to predict risk of Early Treatment of Retinopathy of Prematurity type 1 or 2 ROP. If risk was above a cut-point level, examinations would be indicated. Of 524 infants, 20 (4%) had type 1 ROP and received laser treatment; 28 (5%) had type 2 ROP. The model (Children's Hospital of Philadelphia [CHOP]) accurately predicted all infants with type 1 ROP; missed 1 infant with type 2 ROP, who did not require laser treatment; and would have reduced the number of infants requiring examinations by 49%. Raising the cut point to miss one type 1 ROP case would have reduced the need for examinations by 79%. Using daily weight measurements to calculate weight gain rate resulted in slightly higher examination reduction than weekly measurements. The BW-GA-weight gain CHOP ROP model demonstrated accurate ROP risk assessment and a large reduction in the number of ROP examinations compared with current screening guidelines. As a simple logistic equation, it can be calculated by hand or represented as a nomogram for easy clinical use. However, larger studies are needed to achieve a highly precise estimate of sensitivity prior to clinical application.

  18. InGaAs quantum dots grown on B-type high index GaAs substrates: surface morphologies and optical properties

    NASA Astrophysics Data System (ADS)

    Liang, B. L.; Wang, Zh M.; Mazur, Yu I.; Strelchuck, V. V.; Holmes, K.; Lee, J. H.; Salamo, G. J.

    2006-06-01

    We systematically investigated the correlation between morphological and optical properties of InGaAs self-assembled quantum dots (QDs) grown by solid-source molecular beam epitaxy on GaAs (n 11)B (n = 9, 8, 7, 5, 3, 2) substrates. Remarkably, all InGaAs QDs on GaAs(n 11)B under investigation show optical properties superior to those for ones on GaAs(100) as regards the photoluminescence (PL) linewidth and intensity. The morphology for growth of InGaAs QDs on GaAs (n 11)B, where n = 9, 8, 7, 5, is observed to have a rounded shape with a higher degree of lateral ordering than that on GaAs(100). The optical property and the lateral ordering are best for QDs grown on a (511)B substrate surface, giving a strong correlation between lateral ordering and PL optical quality. Our results demonstrate the potential for high quality InGaAs QDs on GaAs(n 11)B for optoelectronic applications.

  19. The weight of mass or the mess of weight

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

    Gat, U.

    1987-06-24

    This paper explores the cause of confusion associated with the words mass and weight, and offers suggestions to correct the problem. It is recommended that in technical and scientific use, weight shall be restricted to mean force of gravity. Technical standards, ASTM and others, and terminology shall clearly reflect and define weight to be force of gravity. Weight should be avoided in technical context because of its imprecision. Legal, formal, and official language shall use weight to mean force only. Under no circumstances should the SI units of mass, the kilogram, or its derivatives, be associated with weight. The termmore » weight should be avoided in any language and wording that intends to convey a precise or important meaning. ASTM should revise all standards and terminology accordingly.« less

  20. Low resistance ohmic contacts to n-GaN and n-AlGaN using NiAl

    NASA Astrophysics Data System (ADS)

    Ingerly, D. B.; Chen, Y.; William, R. S.; Takeuchi, T.; Chang, Y. A.

    2000-07-01

    The intermetallic compound NiAl (50:50 at. %) has been shown to be a low-resistance ohmic contact to n-GaN and n-AlGaN. NiAl contacts on n-GaN (n=2.5×1017cm-3) had a specific contact resistance of 9.4×10-6 Ω cm2 upon annealing at 850 °C for 5 min. NiAl contacts annealed at 900 °C for 5 min in n-Al0.12Ga0.88N (n=2.4×1018cm-3) and n-Al0.18Ga0.82N (n=2.7×1018cm-3) had specific contact resistances of 2.1×10-5 Ω cm2 and 4.7×10-5 Ω cm2, respectively. Additionally, these contacts were subjected to long-term annealing at 600 °C for 100 h. On n-GaN, the contact specific contact resistance degraded from 9.4×10-6 Ω cm2 to 5.3×10-5 Ω cm2 after the long-term anneal. Contacts to n-Al0.18Ga0.82N showed only slight degradation with a change in contact resistance, from 4.7×10-5 Ω cm2 to 9.2×10-5 Ω cm2. These results demonstrate the NiAl has great promise as a stable, low-resistance contact, particularly to n-AlGaN used in high-temperature applications.

  1. Dementia and legal determination of capacity.

    PubMed

    Delineau, Valeska Maria Eboli Bello; Schultz, Rodrigo Rizek

    2017-06-01

    To assess the legal capacity and guardianship proceedings in patients diagnosed with dementia. Ninety-seven patients diagnosed with dementia and seen at a tertiary hospital were evaluated. Of these 97 patients, 60 (62%) were female. The mean age of the patients was 77.9 years; average schooling was 5.5 years. The main diagnosis was Alzheimer's disease (73%): 16 patients were at a mild stage, eight at a moderate stage and 73 at an advanced stage of dementia. Only 28 patients had been legally declared incapable. The large numbers of patients at an advanced stage of dementia, and the relatively few patients legally declared incapable show that legal issues in dementia are problematic.

  2. 32 CFR 727.6 - Functions of legal assistance officers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... with their personal legal problems, or refer such persons to a civilian lawyer as provided in § 727.9... personal legal problems and may prepare and sign correspondence on behalf of a client, negotiate with..., persons eligible for assistance in connection with their personal legal problems. (4) Shall, subject to...

  3. 32 CFR 727.6 - Functions of legal assistance officers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with their personal legal problems, or refer such persons to a civilian lawyer as provided in § 727.9... personal legal problems and may prepare and sign correspondence on behalf of a client, negotiate with..., persons eligible for assistance in connection with their personal legal problems. (4) Shall, subject to...

  4. Electrical contact of wurtzite GaN mircrodisks on p-type GaN template

    NASA Astrophysics Data System (ADS)

    Tsai, Cheng-Da; Lo, Ikai; Wang, Ying-Chieh; Hsu, Yu-Chi; Shih, Cheng-Hung; Pang, Wen-Yuan; You, Shuo-Ting; Hu, Chia-Hsuan; Chou, Mitch M. C.; Yang, Chen-Chi; Lin, Yu-Chiao

    2015-03-01

    We developed a back processing to fabricate a secure electrical contact of wurtzite GaN microdisk on a transparent p-type GaN template with the orientation, [10-10]disk // [10-10]template. GaN microdisks were grown on LiAlO2 substrate by using plasma-assisted molecular beam epitaxy. In the further study, we analyzed the TEM specimen of a sample with annealed GaN microdisk/p-typed GaN template by selection area diffraction (SAD) to confirm the alignment of the microdisks with the template at the interface. From the I-V measurements performed on the samples, we obtained a threshold voltage of ~ 5.9 V for the current passing through the GaN microdisks with a resistance of ~ 45 K Ω. The electrical contact can be applied to the nanometer-scaled GaN light-emitting diode.

  5. Above room temperature operation of InGaAs/AlGaAs/GaAs quantum cascade lasers

    NASA Astrophysics Data System (ADS)

    Pierścińska, D.; Gutowski, P.; Hałdaś, G.; Kolek, A.; Sankowska, I.; Grzonka, J.; Mizera, J.; Pierściński, K.; Bugajski, M.

    2018-03-01

    In this work we report on the performance of mid-infrared quantum cascade lasers (QCLs) based on strained InGaAs/AlGaAs grown by molecular beam epitaxy on GaAs substrate. Structures were grown with indium content from 1% to 6% in GaAs quantum wells (QW) and 45% of Al in AlGaAs barrier layers. The design results in strained heterostructure, however, no strain relaxation was observed as documented by x-ray diffraction measurements up to ∼3% of In content in QWs. The investigation of heterostructures and devices was performed, including structural measurements and electrooptical characterization of devices. Devices fabricated from epi wafers with 2.64% of In exhibited performance largely improved over GaAs/AlGaAs QCLs. Roughly two times reduction of the threshold current density was observed at lasing wavelength ∼9.45 μm. The lasers operated in pulsed mode up to T = 50 °C with characteristic temperature T 0 = 115 K. The decrease of the threshold current density has been mainly attributed to the reduction of interface roughness scattering and the increase of activation energy for the escape of carriers from the upper laser level to the 3D continuum. Further increase of In content in QWs resulted in the deterioration of device parameters.

  6. Er{sub 1.33}Pt{sub 3}Ga{sub 8}: A modulated variant of the Er{sub 4}Pt{sub 9}Al{sub 24}-structure type

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

    Oswald, Iain W.H.; Gourdon, Olivier; Bekins, Amy

    Single crystals of Er{sub 1.33}Pt{sub 3}Ga{sub 8} were synthesized in a molten Ga flux. Er{sub 1.33}Pt{sub 3}Ga{sub 8} can be considered to be a modulated variant of the Er{sub 4}Pt{sub 9}Al{sub 24}-structure type, where the partial occupancies are ordered. Indeed, the presence of weak satellite reflections indicates a complex organization and distribution of the Er and Ga atoms within the [ErGa] slabs. The structure has been solved based on single crystal X-ray diffraction data in the monoclinic superspace group X2/m(0β0)00 with a commensurate modulated vector q=1/3b*. Precession images also indicate diffusion in the perpendicular direction indicating a partial disorder ofmore » this arrangement from layer to layer. In addition, Er{sub 1.33}Pt{sub 3}Ga{sub 8} shows antiferromagnetic ordering at T{sub N}~5 K. - Graphical abstract: A precession image of the hk0 zone showing weak, periodic, unindexed reflections indicating modulation and representation of the commensurate [ErGa] layer showing the waving modulated occupation. - Highlights: • Single crystals of Er{sub 1.33}Pt{sub 3}Ga{sub 8} were grown from gallium flux. • The structure of Er{sub 1.33}Pt{sub 3}Ga{sub 8} is compared to Er{sub 4}Pt{sub 9}Al{sub 24}. • Structure has been solved in the monoclinic superspace group X2/m(0β0)00 with a commensurate modulated vector q=1/3b*.« less

  7. Polarization-enhanced InGaN/GaN-based hybrid tunnel junction contacts to GaN p-n diodes and InGaN LEDs

    NASA Astrophysics Data System (ADS)

    Mughal, Asad J.; Young, Erin C.; Alhassan, Abdullah I.; Back, Joonho; Nakamura, Shuji; Speck, James S.; DenBaars, Steven P.

    2017-12-01

    Improved turn-on voltages and reduced series resistances were realized by depositing highly Si-doped n-type GaN using molecular beam epitaxy on polarization-enhanced p-type InGaN contact layers grown using metal-organic chemical vapor deposition. We compared the effects of different Si doping concentrations and the addition of p-type InGaN on the forward voltages of p-n diodes and light-emitting diodes, and found that increasing the Si concentrations from 1.9 × 1020 to 4.6 × 1020 cm-3 and including a highly doped p-type InGaN at the junction both contributed to reductions in the depletion width, the series resistance of 4.2 × 10-3-3.4 × 10-3 Ω·cm2, and the turn-on voltages of the diodes.

  8. A convenient route to [68Ga]Ga-MAA for use as a particulate PET perfusion tracer.

    PubMed

    Mathias, Carla J; Green, Mark A

    2008-12-01

    A convenient method is described for compounding [(68)Ga]Ga-MAA (MAA=macroaggregated human serum albumin) with the eluate of a commercially available TiO(2)-based (68)Ge/(68)Ga generator. The final [(68)Ga]Ga-MAA product was obtained with an 81.6+/-5.3% decay-corrected radiochemical yield and a radiochemical purity of 99.8+/-0.1% (n=5). Microscopic examination showed the [(68)Ga]Ga-MAA product to remain within the original particle size range. The entire procedure, from generator elution to delivery of the final [(68)Ga]Ga-MAA suspension, could be completed in 25 min. Only 4.4+/-0.9% of the total (68)Ge breakthrough remaining associated with the final [(68)Ga]Ga-MAA product. The procedure allows reasonably convenient preparation of [(68)Ga]Ga-MAA in a fashion that can be readily adapted to sterile product compounding for human use.

  9. Properties and Bibliography of GaSe

    DTIC Science & Technology

    1994-02-01

    Musaev, A. E. Bakhyshev, N. M. Gasanly and L. G. Musaeva . (1975). "Anisotropy of the optical constants of GaS and GaSe near the absorption edge." Sov...Phys. Semiconductors. 9 94-95 Russian ref.: Fiz. Tekh. Poluprovodn. 9 142-145 (January 1975). Akhundov, G. A., L. G. Musaeva and M. D. Khomutova

  10. Crystal field effects in the intermetallic R Ni3Ga9 (R =Tb , Dy, Ho, and Er) compounds

    NASA Astrophysics Data System (ADS)

    Silva, L. S.; Mercena, S. G.; Garcia, D. J.; Bittar, E. M.; Jesus, C. B. R.; Pagliuso, P. G.; Lora-Serrano, R.; Meneses, C. T.; Duque, J. G. S.

    2017-04-01

    In this paper, we report temperature-dependent magnetic susceptibility, electrical resistivity, and heat-capacity experiments in the family of intermetallic compounds R Ni3Ga9 (R = Tb, Dy, Ho, and Er). Single-crystalline samples were grown using Ga self-flux method. These materials crystallize in a trigonal ErNi3Al9 -type structure with space group R 32 . They all order antiferromagnetically with TN<20 K . The anisotropic magnetic susceptibility presents large values of the ratio χeasy/χhard indicating strong crystalline electric-field (CEF) effects. The evolution of the crystal-field scheme for each R was analyzed in detail by using a spin model including anisotropic nearest-neighbor Ruderman-Kittel-Kasuya-Yosida interaction and the trigonal CEF Hamiltonian. Our analysis allows one to understand the distinct direction of the ordered moments along the series—the Tb-, Dy-, and Ho-based compounds have the ordered magnetic moments in the easy ab plane and the Er sample magnetization easy axis is along the c ̂ direction.

  11. Development of GaAs/Si and GaAs/Si monolithic structures for future space solar cells

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.; Vernon, S. M.; Wolfson, R. G.; Tobin, S. P.

    1984-01-01

    The results of heteroepitaxial growth of GaAs and GaAlAs directly on Si are presented, and applications to new cell structures are suggested. The novel feature is the elimination of a Ge lattice transition region. This feature not only reduces the cost of substrate preparation, but also makes possible the fabrication of high efficiency monolithic cascade structures. All films to be discussed were grown by organometallic chemical vapor deposition at atmospheric pressure. This process yielded reproducible, large-area films of GaAs, grown directly on Si, that are tightly adherent and smooth, and are characterized by a defect density of 5 x 10(6) power/sq cm. Preliminary studies indicate that GaAlAs can also be grown in this way. A number of promising applications are suggested. Certainly these substrates are ideal for low-weight GaAs space solar ells. For very high efficiency, the absence of Ge makes the technology attractive for GaAlAs/Si monolithic cascades, in which the Si substrates would first be provided with a suitable p/n junction. An evaluation of a three bandgap cascade consisting of appropriately designed GaAlAs/GaAs/Si layers is also presented.

  12. Gibberellins and stem growth in Arabidopsis thaliana. Effects of photoperiod on expression of the GA4 and GA5 loci.

    PubMed

    Xu, Y L; Gage, D A; Zeevaart, J A

    1997-08-01

    Arabidopsis thaliana (L.) Heynh. is a quantitative long-day (LD) rosette plant in which stem growth is mediated by gibberellins (CAs). Application of GAs to plants in short-day (SD) conditions resulted in rapid stem elongation and flower formation, with GA4 and GA9 being equally effective, and GA1 showing lower activity. The effects of photoperiod on the levels of endogenous GAs were measured by combined gas chromatography-mass spectrometry with selected ion monitoring. When plants were transferred from SD to LD conditions there was a slight decrease in the level of GA53 and an increase in the levels of C19-GAs, GA9, GA20, GA1, and GA8, indicating that GA 20-oxidase activity is stimulated in LD conditions. Expression of GA5, which encodes GA 20-oxidase, was highest in elongating stems and was correlated with the rate of stem elongation. By contrast, GA4, which encodes 3 beta-hydroxylase, showed low expression in stems and its expression was not correlated with the rate of stem elongation. We conclude that stem elongation in LD conditions is at least in part due to increased expression of GA5, whereas expression of GA4 is not under photoperiodic control.

  13. FInvestigation of enhancement mode HfO2 insulated N-polarity GaN/InN/GaN/In0.9Al0.1N heterostructure MISHEMT for high-frequency applications

    NASA Astrophysics Data System (ADS)

    Mohanbabu, A.; Mohankumar, N.; Godwin Raj, D.; Sarkar, Partha

    2017-08-01

    In this paper, we examined normally-OFF N-polar InN-channel Metal insulated semiconductor high-electron mobility transistors (MISHEMTs) device with a relaxed In0.9Al0.1N buffer layer. In addition, the enhancement-mode operation of the N-polar structure was investigated. The effect of scaling in N-polar MISHEMT, such as the dielectric and the channel thickness, alter the electrical behavior of the device. We have achieved a maximum drain current of 1.17 A/mm, threshold voltage (VT) =0.728 V, transconductance (gm) of 2.9 S mm-1, high ION/IOFF current ratio of 3.23×103, lowest ON-state resistance (RON) of 0.41 Ω mm and an intrinsic delay time (τ) of 1.456 Fs along with high-frequency performance with ft/ fmaxof 90 GHz/109 GHz and 180 GHz/260 GHz for TCH =0.5 nm at Vds =0.5 V and 1.0 V. The numerically simulated results of highly confined GaN/InN/GaN/In0.9Al0.1N heterostructure MISHEMT exhibits outstanding potential as one of the possibility to replace presently used N-polar MISHEMTs for delivering high power density and frequency at RF/power amplifier applications.

  14. A Convenient Route to [68Ga]Ga-MAA for Use as a Particulate PET Perfusion Tracer

    PubMed Central

    Mathias, Carla J.; Green, Mark A.

    2008-01-01

    A convenient method is described for compounding [68Ga]Ga-MAA (MAA = macroaggregated human serum albumin) with the eluate of a commercially available TiO2-based 68Ge/68Ga generator. The final [68Ga]Ga-MAA product was obtained with an 81.6 ± 5.3% decay-corrected radiochemical yield and a radiochemical purity of 99.8 ± 0.1% (n = 5). Microscopic examination showed the [68Ga]Ga-MAA product to remain within the original particle size range. The entire procedure, from generator elution to delivery of the final [68Ga]Ga-MAA suspension, could be completed in 25 minutes. Only 4.4 ± 0.9% of the total 68Ge breakthrough remaining associated with the final [68Ga]Ga-MAA product. The procedure allows reasonably convenient preparation of [68Ga]Ga-MAA in a fashion that can be readily adapted to sterile product compounding for human use. PMID:18640845

  15. Study of the effects of GaN buffer layer quality on the dc characteristics of AlGaN/GaN high electron mobility transistors

    DOE PAGES

    Ahn, Shihyun; Zhu, Weidi; Dong, Chen; ...

    2015-04-21

    Here we studied the effect of buffer layer quality on dc characteristics of AlGaN/GaN high electron mobility (HEMTs). AlGaN/GaN HEMT structures with 2 and 5 μm GaN buffer layers on sapphire substrates from two different vendors with the same Al concentration of AlGaN were used. The defect densities of HEMT structures with 2 and 5 μm GaN buffer layer were 7 × 10 9 and 5 × 10 8 cm ₋2, respectively, as measured by transmission electron microscopy. There was little difference in drain saturation current or in transfer characteristics in HEMTs on these two types of buffer. However, theremore » was no dispersion observed on the nonpassivated HEMTs with 5 μm GaN buffer layer for gate-lag pulsed measurement at 100 kHz, which was in sharp contrast to the 71% drain current reduction for the HEMT with 2 μm GaN buffer layer.« less

  16. Integrating AlGaN/GaN high electron mobility transistor with Si: A comparative study of integration schemes

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

    Mohan, Nagaboopathy; Raghavan, Srinivasan; Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore 560012

    2015-10-07

    AlGaN/GaN high electron mobility transistor stacks deposited on a single growth platform are used to compare the most common transition, AlN to GaN, schemes used for integrating GaN with Si. The efficiency of these transitions based on linearly graded, step graded, interlayer, and superlattice schemes on dislocation density reduction, stress management, surface roughness, and eventually mobility of the 2D-gas are evaluated. In a 500 nm GaN probe layer deposited, all of these transitions result in total transmission electron microscopy measured dislocations densities of 1 to 3 × 10{sup 9}/cm{sup 2} and <1 nm surface roughness. The 2-D electron gas channels formed atmore » an AlGaN-1 nm AlN/GaN interface deposited on this GaN probe layer all have mobilities of 1600–1900 cm{sup 2}/V s at a carrier concentration of 0.7–0.9 × 10{sup 13}/cm{sup 2}. Compressive stress and changes in composition in GaN rich regions of the AlN-GaN transition are the most effective at reducing dislocation density. Amongst all the transitions studied the step graded transition is the one that helps to implement this feature of GaN integration in the simplest and most consistent manner.« less

  17. Effects of phase transformation on the microstructures and magnetostriction of Fe-Ga and Fe-Ga-Zn ferromagnetic shape memory alloys

    NASA Astrophysics Data System (ADS)

    Lin, Yin-Chih; Lin, Chien-Feng

    2015-05-01

    The phase transformation and magnetostriction of bulk Fe73Ga27 and Fe73Ga18Zn9 (at. %) ferromagnetic shape memory alloys (FSMs) were investigated by transmission electron microscopy (TEM), x-ray diffraction (XRD), and a magnetostrictive-meter setup. For the Fe73Ga27 FSM alloy solution treated at 1100 °C for 4 h and quenched in ice brine, the antiphase boundary segments of the D03 domain were observed in the A2 (disordered) matrix, and the Fe73Ga27 FSM alloy had an optimal magnetostriction (λ‖s = 71 × 10-6 and λ⊥s = -31 × 10-6). In Fe73Ga27 FSM alloy as-quenched, aged at 700 °C for 24 h, and furnace cooled, D03 nanoclusters underwent phase transformation to an intermediate tetragonal phase (i.e., L10-like martensite) via Bain distortion, and finally L12 (Fe3Ga) structures precipitated, as observed by TEM and XRD. The L10-like martensite and L12 phases in the aged Fe73Ga27 FSM alloy drastically decreased the magnetostriction from positive to negative (λ‖s = -20 × 10-6 and λ⊥s = -8 × 10-6). However, in Fe73Ga18Zn9 FSM alloy as-quenched and aged, the phase transformation of D03 to an intermediate tetragonal martensite phase and precipitation of L12 structures were not found. The results indicate that the aged Fe73Ga18Zn9 FSM alloy maintained stable magnetostriction (λ‖s = 36 × 10-6 and λ⊥s = -31 × 10-6). Adding Zn can improve the ferromagnetic shape memory effect of aged Fe73Ga18Zn9 alloy, which may be useful in application of the alloy in high temperature environments.

  18. Isotype InGaN/GaN heterobarrier diodes by ammonia molecular beam epitaxy

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

    Fireman, Micha N.; Browne, David A.; Speck, James S.

    The design of isotype InGaN/GaN heterobarrier diode structures grown by ammonia molecular beam epitaxy is presented. On the (0001) Ga-polar plane, a structure consisting of a surface n{sup +} GaN contact layer, followed by a thin InGaN layer, followed by a thick unintentionally doped (UID) GaN layer, and atop a buried n{sup +} GaN contact layer induces a large conduction band barrier via a depleted UID GaN layer. Suppression of reverse and subthreshold current in such isotype barrier devices under applied bias depends on the quality of this composite layer polarization. Sample series were grown under fixed InGaN growth conditionsmore » that varied either the UID GaN NH{sub 3} flow rate or the UID GaN thickness, and under fixed UID GaN growth conditions that varied InGaN growth conditions. Decreases in subthreshold current and reverse bias current were measured for thicker UID GaN layers and increasing InGaN growth rates. Temperature-dependent analysis indicated that although extracted barrier heights were lower than those predicted by 1D Schrödinger Poisson simulations (0.9 eV–1.4 eV for In compositions from 10% to 15%), optimized growth conditions increased the extracted barrier height from ∼11% to nearly 85% of the simulated values. Potential subthreshold mechanisms are discussed, along with those growth factors which might affect their prevalence.« less

  19. Ultra-Thin, Triple-Bandgap GaInP/GaAs/GaInAs Monolithic Tandem Solar Cells

    NASA Technical Reports Server (NTRS)

    Wanlass, M. W.; Ahrenkiel, S. P.; Albin, D. S.; Carapella, J. J.; Duda, A.; Emery, K.; Geisz, J. F.; Jones, K.; Kurtz, Sarah; Moriarty, T.; hide

    2007-01-01

    The performance of state-of-the-art, series-connected, lattice-matched (LM), triple-junction (TJ), III-V tandem solar cells could be improved substantially (10-12%) by replacing the Ge bottom subcell with a subcell having a bandgap of approx.1 eV. For the last several years, research has been conducted by a number of organizations to develop approx.1-eV, LM GaInAsN to provide such a subcell, but, so far, the approach has proven unsuccessful. Thus, the need for a high-performance, monolithically integrable, 1-eV subcell for TJ tandems has remained. In this paper, we present a new TJ tandem cell design that addresses the above-mentioned problem. Our approach involves inverted epitaxial growth to allow the monolithic integration of a lattice-mismatched (LMM) approx.1- eV GaInAs/GaInP double-heterostructure (DH) bottom subcell with LM GaAs (middle) and GaInP (top) upper subcells. A transparent GaInP compositionally graded layer facilitates the integration of the LM and LMM components. Handle-mounted, ultra-thin device fabrication is a natural consequence of the inverted-structure approach, which results in a number of advantages, including robustness, potential low cost, improved thermal management, incorporation of back-surface reflectors, and possible reclamation/reuse of the parent crystalline substrate for further cost reduction. Our initial work has concerned GaInP/GaAs/GaInAs tandem cells grown on GaAs substrates. In this case, the 1- eV GaInAs experiences 2.2% compressive LMM with respect to the substrate. Specially designed GaInP graded layers are used to produce 1-eV subcells with performance parameters nearly equaling those of LM devices with the same bandgap (e.g., LM, 1-eV GaInAsP grown on InP). Previously, we reported preliminary ultra-thin tandem devices (0.237 cm2) with NREL-confirmed efficiencies of 31.3% (global spectrum, one sun) (1), 29.7% (AM0 spectrum, one sun) (2), and 37.9% (low-AOD direct spectrum, 10.1 suns) (3), all at 25 C. Here, we include

  20. Four-junction AlGaAs/GaAs laser power converter

    NASA Astrophysics Data System (ADS)

    Huang, Jie; Sun, Yurun; Zhao, Yongming; Yu, Shuzhen; Dong, Jianrong; Xue, Jiping; Xue, Chi; Wang, Jin; Lu, Yunqing; Ding, Yanwen

    2018-04-01

    Four-junction AlGaAs/GaAs laser power converters (LPCs) with n+-GaAs/p+-Al0.37Ga0.63As heterostructure tunnel junctions (TJs) have been designed and grown by metal-organic chemical vapor deposition (MOCVD) for converting the power of 808 nm lasers. A maximum conversion efficiency η c of 56.9% ± 4% is obtained for cells with an aperture of 3.14 mm2 at an input laser power of 0.2 W, while dropping to 43.3% at 1.5 W. Measured current–voltage (I–V) characteristics indicate that the performance of the LPC can be further improved by increasing the tunneling current density of TJs and optimizing the thicknesses of sub-cells to achieve current matching in LPC. Project financially supported by the National Natural Science Foundation of China (No. 61376065) and Zhongtian Technology Group Co. Ltd.

  1. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  2. (Al)GaInP/GaAs Tandem Solar Cells for Power Conversion at Elevated Temperature and High Concentration

    DOE PAGES

    Perl, Emmett E.; Simon, John; Friedman, Daniel J.; ...

    2018-01-12

    We demonstrate dual-junction (Al)GaInP/GaAs solar cells designed for operation at 400 degrees C and 1000x concentration. For the top junction, we compare (Al)GaInP solar cells with room-temperature bandgaps ranging from 1.9 to 2.0 eV. At 400 degrees C, we find that ~1.9 eV GaInP solar cells have a higher open-circuit voltage and a lower sheet resistance than higher bandgap (Al)GaInP solar cells, giving them a clear advantage in a tandem configuration. Dual-junction GaInP/GaAs solar cells are fabricated, and we show temperature-dependent external quantum efficiency, illuminated current-voltage, and concentrator measurements from 25 degrees C to 400 degrees C. We measure amore » power conversion efficiency of 16.4% +/- 1% at 400 degrees C and 345 suns for the best dual-junction cell, and discuss multiple pathways to improve the performance further. After undergoing a 200 h soak at 400 degrees C, the dual-junction device shows a relative loss in efficiency of only ~1%.« less

  3. (Al)GaInP/GaAs Tandem Solar Cells for Power Conversion at Elevated Temperature and High Concentration

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

    Perl, Emmett E.; Simon, John; Friedman, Daniel J.

    We demonstrate dual-junction (Al)GaInP/GaAs solar cells designed for operation at 400 degrees C and 1000x concentration. For the top junction, we compare (Al)GaInP solar cells with room-temperature bandgaps ranging from 1.9 to 2.0 eV. At 400 degrees C, we find that ~1.9 eV GaInP solar cells have a higher open-circuit voltage and a lower sheet resistance than higher bandgap (Al)GaInP solar cells, giving them a clear advantage in a tandem configuration. Dual-junction GaInP/GaAs solar cells are fabricated, and we show temperature-dependent external quantum efficiency, illuminated current-voltage, and concentrator measurements from 25 degrees C to 400 degrees C. We measure amore » power conversion efficiency of 16.4% +/- 1% at 400 degrees C and 345 suns for the best dual-junction cell, and discuss multiple pathways to improve the performance further. After undergoing a 200 h soak at 400 degrees C, the dual-junction device shows a relative loss in efficiency of only ~1%.« less

  4. Legal consequences of kleptomania.

    PubMed

    Grant, Jon E; Odlaug, Brian L; Davis, Andrew A; Kim, Suck Won

    2009-12-01

    Although studies have examined clinical characteristics of kleptomania, no previous studies have examined the legal consequences of kleptomania. From 2001 to 2007, 101 adult subjects (n = 27 [26.7%] males) with DSM-IV kleptomania were assessed on sociodemographics and clinical characteristics including symptom severity, comorbidity, and legal repercussions. Of 101 subjects with kleptomania, 73.3% were female. Mean age of shoplifting onset was 19.4 +/- 12.0 years, and subjects shoplifted a mean of 8.2 +/- 11.0 years prior to meeting full criteria for kleptomania. Co-occurring depressive, substance use, and impulse control disorders were common. Sixty-nine subjects with kleptomania (68.3%) had been arrested, 36.6% had been arrested but not convicted, 20.8% had been convicted and incarcerated after conviction, while only 10.9% had been convicted and not incarcerated after conviction. Kleptomania is associated with significant legal repercussions. The findings emphasize the need for rigorous treatment approaches to target kleptomania symptoms and prevent re-offending.

  5. Defects and annealing studies in 1-Me electron irradiated (AlGa)As-GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Li, S. S.; Wang, W. L.; Loo, R. Y.; Rahilly, W. P.

    1982-01-01

    The deep-level defects and recombination mechanisms in the one-MeV electron irradiated (AlGa)As-GaAs solar cells under various irradiation and annealing conditions are discussed. Deep-level transient spectroscopy (DLTS) and capacitance-voltage (CV) techniques were used to determine the defect and recombination parameters such as energy levels and defect density, carrier capture cross sections and lifetimes for both electron and hole traps as well as hole diffusion lengths in these electron irradiated GaAs solar cells. GaAs solar cells used in this study were prepared by the infinite solution melt liquid phase epitaxial (LPE) technique at Hughes Research Lab., with (Al0.9Ga0.1)-As window layer, Be-diffused p-GaAs layer on Sn-doped n-GaAs or undoped n-GaAs active layer grown on n(+)-GaAs substrate. Mesa structure with area of 5.86x1000 sq cm was fabricated. Three different irradiation and annealing experiments were performed on these solar cells.

  6. Room temperature, single mode emission from two-section coupled cavity InGaAs/AlGaAs/GaAs quantum cascade laser

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

    Pierściński, K., E-mail: kamil.pierscinski@ite.waw.pl; Pierścińska, D.; Pluska, M.

    2015-10-07

    Room temperature, single mode, pulsed emission from two-section coupled cavity InGaAs/AlGaAs/GaAs quantum cascade laser fabricated by focused ion beam processing is demonstrated and analyzed. The single mode emission is centered at 1059.4 cm{sup −1} (9.44 μm). A side mode suppression ratio of 43 dB was achieved. The laser exhibits a peak output power of 15 mW per facet at room temperature. The stable, single mode emission is observed within temperature tuning range, exhibiting shift at rate of 0.59 nm/K.

  7. Eu2+-doped Ba2GaB4O9Cl blue-emitting phosphor with high color purity for near-UV-pumped white light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Gao, Zhiwen; Deng, Huajuan; Xue, Na; Jeong, Jung Hyun; Yu, Ruijin

    2018-01-01

    Eu2+-doped borate fluoride Ba2GaB4O9Cl was synthesized by the conventional high-temperature solid-state reaction. The crystal structure and luminescence properties of the phosphors, as well as their thermal luminescence quenching capabilities and CIE chromaticity coordinates were systematically investigated. Under the excitation at 340 nm, the phosphor exhibited an asymmetric broad-band blue emission with a peak at 445 nm, which is ascribed to the 4f-5d transition of Eu2+. It was further proved that energy transfer among the nearest neighbor ions is the major mechanism for concentration quenching of Eu2+ in Ba2-xGaB4O9Cl:xEu2+ phosphors. The luminescence quenching temperature is 432 K. The CIE color coordinates are very close to those of BaMgAl10O17:Eu2+ (BAM). All the properties indicated that the blue-emitting Ba2GaB4O9Cl:Eu2+ phosphor has potential application in white LEDs.

  8. 2.9, 2.36, and 1.96 Ga zircons in orthogneiss south of the Red River shear zone in Viet Nam: evidence from SHRIMP U-Pb dating and tectonothermal implications

    NASA Astrophysics Data System (ADS)

    Nam, Tran Ngoc; Toriumi, Mitsuhiro; Sano, Yuji; Terada, Kentaro; Thang, Ta Trong

    2003-05-01

    Orthogneissic rocks coexisting with migmatites and containing small amphibolite lenses are exposed in the center of the metamorphic belt which runs parallel to the Day Nui Con Voi-Red River shear zone in northern Viet Nam. The orthogneiss complex has given some radiogenic dates of Early Proterozoic and Late Archean, which are the oldest ages ever registered for the Southeast Asian continent. Zircon grains separated from three samples of the orthogneiss complex have been dated to establish the protolith age and the timing of high-grade tectonothermal events in the complex. Sixty-five SHRIMP U-Th-Pb analyses of these zircons define three age groups of 2.84-2.91, 2.36, and 1.96 Ga. The age groups correspond to three periods of zircon generation. The oldest ˜2.9 Ga cores indicate a minimum age for the protolith of the orthogneiss complex. Two younger generations (including ˜2.36 Ga outer-cores and ˜1.96 Ga rims) probably grew during later high-grade tectono-metamorphic events, which were previously suggested by K-Ar and 40Ar/ 39Ar cooling ages of ˜2.0 Ga for synkinematic hornblendes. An early thermal history of the orthogneiss complex has been constrained, including a primary magma-crystallization stage starting at ˜2.9 Ga, followed by two Early Proterozoic (˜2.36 and ˜1.96 Ga) high-grade tectonothermal events. The ca. 2.9 Ga protolith age of the orthogneiss complex documented in this study provides new convincing evidence for the presence of Archean rocks in Indochina, and clearly indicates that the crustal evolution of northern Viet Nam started as early as Late Archean time.

  9. Holiday Weight Management by Successful Weight Losers and Normal Weight Individuals

    ERIC Educational Resources Information Center

    Phelan, Suzanne; Wing, Rena R.; Raynor, Hollie A.; Dibello, Julia; Nedeau, Kim; Peng, Wanfeng

    2008-01-01

    This study compared weight control strategies during the winter holidays among successful weight losers (SWL) in the National Weight Control Registry and normal weight individuals (NW) with no history of obesity. SWL (n = 178) had lost a mean of 34.9 kg and had kept greater than or equal to 13.6 kg off for a mean of 5.9 years. NW (n = 101) had a…

  10. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  11. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  12. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  13. Transport, Thermal, and Magnetic Properties of YbNi3X9 (X = Al, Ga): A Newly Synthesized Yb-Based Kondo Lattice System

    NASA Astrophysics Data System (ADS)

    Yamashita, Tetsuro; Miyazaki, Ryoichi; Aoki, Yuji; Ohara, Shigeo

    2012-03-01

    We have succeeded in synthesizing a new Yb-based Kondo lattice system, YbNi3X9 (X = Al, Ga). Our study reveals that YbNi3Al9 shows typical features of a heavy-fermion antiferromagnet with a Néel temperature of TN = 3.4 K. All of the properties reflect a competition between the Kondo effect and the crystalline electric field (CEF) effect. The moderate heavy-fermion state leads to an enhanced Sommerfeld coefficient of 100 mJ/(mol\\cdotK2), even if ordered antiferromagnetically. On the other hand, the isostructural gallide YbNi3Ga9 is an intermediate-valence system with a Kondo temperature of TK = 570 K. A large hybridization scale can overcome the CEF splitting energy, and a moderately heavy Fermi-liquid ground state with high local moment degeneracy should form at low temperatures. Note that the quality of single-crystalline YbNi3X9 is extremely high compared with those of other Yb-based Kondo lattice compounds. We conclude that YbNi3X9 is a suitable system for investigating the electronic structure of Yb-based Kondo lattice systems from a heavy-fermion system with an antiferromagnetically ordered ground state to an intermediate-valence system.

  14. Improved InGaN/GaN light-emitting diodes with a p-GaN/n-GaN/p-GaN/n-GaN/p-GaN current-spreading layer.

    PubMed

    Zhang, Zi-Hui; Tan, Swee Tiam; Liu, Wei; Ju, Zhengang; Zheng, Ke; Kyaw, Zabu; Ji, Yun; Hasanov, Namig; Sun, Xiao Wei; Demir, Hilmi Volkan

    2013-02-25

    This work reports both experimental and theoretical studies on the InGaN/GaN light-emitting diodes (LEDs) with optical output power and external quantum efficiency (EQE) levels substantially enhanced by incorporating p-GaN/n-GaN/p-GaN/n-GaN/p-GaN (PNPNP-GaN) current spreading layers in p-GaN. Each thin n-GaN layer sandwiched in the PNPNP-GaN structure is completely depleted due to the built-in electric field in the PNPNP-GaN junctions, and the ionized donors in these n-GaN layers serve as the hole spreaders. As a result, the electrical performance of the proposed device is improved and the optical output power and EQE are enhanced.

  15. K and Ba distribution in the structures of the clathrate compounds K(x)Ba(16-x)(Ga,Sn)136 (x = 0.8, 4.4, and 12.9) and K(x)Ba(8-x)(Ga,Sn)46 (x = 0.3).

    PubMed

    Schäfer, Marion C; Bobev, Svilen

    2013-04-01

    Studies of the K-Ba-Ga-Sn system produced the clathrate compounds K(0.8(2))Ba(15.2(2))Ga(31.0(5))Sn(105.0(5)) [a = 17.0178 (4) Å], K(4.3(3))Ba(11.7(3))Ga(27.4(4))Sn(108.6(4)) [a = 17.0709 (6) Å] and K(12.9(2))Ba(3.1(2))Ga(19.5(4))Sn(116.5(4)) [a = 17.1946 (8) Å], with the type-II structure (cubic, space group Fd3m), and K(7.7(1))Ba(0.3(1))Ga(8.3(4))Sn(37.7(4)) [a = 11.9447 (4) Å], with the type-I structure (cubic, space group Pm3n). For the type-II structures, only the smaller (Ga,Sn)24 pentagonal dodecahedral cages are filled, while the (Ga,Sn)28 hexakaidecahedral cages remain empty. The unit-cell volume is directly correlated with the K:Ba ratio, since an increasing amount of monovalent K occupying the cages causes a decreasing substitution of the smaller Ga in the framework. All three formulae have an electron count that is in good agreement with the Zintl-Klemm rules. For the type-I compound, all framework sites are occupied by a mixture of Ga and Sn atoms, with Ga showing a preference for Wyckoff site 6c. The (Ga,Sn)20 pentagonal dodecahedral cages are occupied by statistically disordered K and Ba atoms, while the (Ga,Sn)24 tetrakaidecahedral cages encapsulate only K atoms. Large anisotropic displacement parameters for K in the latter cages suggest an off-centering of the guest atoms.

  16. GaN HEMTs with p-GaN gate: field- and time-dependent degradation

    NASA Astrophysics Data System (ADS)

    Meneghesso, G.; Meneghini, M.; Rossetto, I.; Canato, E.; Bartholomeus, J.; De Santi, C.; Trivellin, N.; Zanoni, E.

    2017-02-01

    GaN-HEMTs with p-GaN gate have recently demonstrated to be excellent normally-off devices for application in power conversion systems, thanks to the high and robust threshold voltage (VTH>1 V), the high breakdown voltage, and the low dynamic Ron increase. For this reason, studying the stability and reliability of these devices under high stress conditions is of high importance. This paper reports on our most recent results on the field- and time-dependent degradation of GaN-HEMTs with p-GaN gate submitted to stress with positive gate bias. Based on combined step-stress experiments, constant voltage stress and electroluminescence testing we demonstrated that: (i) when submitted to high/positive gate stress, the transistors may show a negative threshold voltage shift, that is ascribed to the injection of holes from the gate metal towards the p-GaN/AlGaN interface; (ii) in a step-stress experiment, the analyzed commercial devices fail at gate voltages higher than 9-10 V, due to the extremely high electric field over the p-GaN/AlGaN stack; (iii) constant voltage stress tests indicate that the failure is also time-dependent and Weibull distributed. The several processes that can explain the time-dependent failure are discussed in the following.

  17. Decagonal quasicrystal and related crystalline phases in Mn-Ga alloys with 52 to 63 a/o Ga

    NASA Astrophysics Data System (ADS)

    Wu, J. S.; Kuo, K. H.

    1997-03-01

    A decagonal quasicrystal (DQC) and six related intermetallic phases with large unit cells have been found in binary Mn-Ga alloys with 52 to 63 at. pct Ga by means of transmission electron microscopy (TEM). As does the Al-Mn DQC, the Ga-Mn DQC also has a periodicity of 1.25 nm along its tenfold axis. However, its Mn content, determined by electron microprobe X-ray analysis (about 45 to 50 at. pct Mn), is much higher than that of the Al-Mn DQC (about 20 to 30 at. pct Mn). The compositions of the intermetallic phases are about 53, 56, 58, and 62 at. pct Ga, corresponding respectively to the unknown structures of MnGa (50.7 to 53.4 at. pct Ga), Mn5Ga6 (55 at pct Ga), Mn5Ga7 (57.9 at. pct Ga), and Mn3Ga5 (62.9 at. pct Ga) given in the binary Mn-Ga phase diagram ( Metals Hand-book, T.B. Massalski, J.L. Murray, L.H. Benneft, and H. Baker, eds., ASM, Metals Park, OH, 1986, vol. 2, p. 1144). Their lattice types have been determined by selected area electron diffraction. The ferromagnetic Mn3Ga5 is tetragonal, a=1.25 nm and c=2.50 nm; Mn5Ga7 is orthorhombic, a=4.57 nm, b=1.25 nm, and c=1.44 nm; Mn5Ga6 has two different but closely related orthorhombic unit cells, a=1.26 nm, b=1.25 nm, and c=1.48 nm as well as a=0.77 nm, b=1.25 nm, and c=2.36 nm; MnGa also has two different and related unit cells, one orthorhombic with a=2.04 nm, b=1.25 nm, and c=1.48 nm and the other monoclinic with a=2.59 nm, b=1.25 nm, c=1.15 nm, and β≈=110 deg. All these orthorhombic phases have b=1.25 nm, being the same as the periodicity along the tenfold axis of the Ga-Mn and Al-Mn DQCs. Moreover, all these six intermetallic phases give electron diffraction patterns displaying a pseudo-tenfold distribution of strong diffraction spots and are considered to be crystalline approximants of the Ga-Mn DQC.

  18. Crystal growth and piezoelectric properties of Ca3Ta(Ga0.9Sc0.1)3Si2O14 bulk single crystal

    NASA Astrophysics Data System (ADS)

    Igarashi, Yu; Yokota, Yuui; Ohashi, Yuji; Inoue, Kenji; Yamaji, Akihiro; Shoji, Yasuhiro; Kamada, Kei; Kurosawa, Shunsuke; Yoshikawa, Akira

    2018-03-01

    Ca3Ta(Ga0.9Sc0.1)3Si2O14 langasite-type single crystal with a diameter of 1 in. was grown by Czochralski (Cz) method. Obtained crystal had good crystallinity and its lattice constants exceeded those of Ca3TaGa3Si2O14 (CTGS) according to the X-ray analysis. A crack-free specimen cut from the grown crystal was used for the measurements of dielectric constant ε11T/ε0, electromechanical coupling factor k12, and piezoelectric constant d11. The accuracies of these measurements were better than those for the crystal grown by micro-pulling-down (μ-PD) method. Substitution of Ga with Sc resulted modification of these constants in the directions opposite to those observed after partial substitution of Ga (of CTGS) with Al. This suggests that increase of |d14| was most probably associated with enlargement of average size of the Ga sites. The crystal reported here had greater dimensions as compared to analogous crystals grown by the μ-PD method. As a result, accuracy of determination of acoustic constants of this material may be improved.

  19. Uniformity of dc and rf performance of MBE-grown AlGaN/GaN HEMTS on HVPE-grown buffers

    NASA Astrophysics Data System (ADS)

    Gillespie, J. K.; Fitch, R. C.; Moser, N.; Jenkins, T.; Sewell, J.; Via, D.; Crespo, A.; Dabiran, A. M.; Chow, P. P.; Osinsky, A.; Mastro, M. A.; Tsvetkov, D.; Soukhoveev, V.; Usikov, A.; Dmitriev, V.; Luo, B.; Pearton, S. J.; Ren, F.

    2003-10-01

    AlGaN/GaN high electron mobility transistors (HEMTs) were grown by molecular beam epitaxy (MBE) on 2 in. diameter GaN buffer layers grown by hydride vapor epitaxy (HVPE) on sapphire substrates. HEMTs with 1 μm gate length displayed excellent dc and rf performance uniformity with up to 258 separate devices measured for each parameter. The drain-source saturation current was 561 mA with a standard deviation of 1.9% over the 2 in. diameter, with a corresponding transconductance of 118 ± 3.9 mS/mm. The threshold voltage was -5.3 ± 0.07 V. The rf performance uniformity was equally good, with an fT of 8.6 ± 0.8 GHz and fmax of 12.8 ± 2.5 GHz. The results show the excellent uniformity of the MBE technique for producing AlGaN/GaN HEMTs and also the ability of HVPE to provide high quality buffers at low cost.

  20. Dealing with Legal Issues. PACE Revised. Level 2. Unit 9. Research & Development Series No. 240BB9.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This unit on dealing with legal issues in a small business, the ninth in a series of 18 modules, is on the second level of the revised PACE (Program for Acquiring Competence in Entrepreneurship) comprehensive curriculum. Geared to advanced secondary and beginning postsecondary or adult students, the modules provide an opportunity to learn about…

  1. Comparative investigation of InGaP/GaAs/GaAsBi and InGaP/GaAs heterojunction bipolar transistors

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

    Wu, Yi-Chen; Tsai, Jung-Hui, E-mail: jhtsai@nknucc.nknu.edu.tw; Chiang, Te-Kuang

    2015-10-15

    In this article the characteristics of In{sub 0.49}Ga{sub 0.51}P/GaAs/GaAs{sub 0.975}Bi{sub 0.025} and In{sub 0.49}Ga{sub 0.51}P/GaAs heterojunction bipolar transistor (HBTs) are demonstrated and compared by two-dimensional simulated analysis. As compared to the traditional InGaP/GaAs HBT, the studied InGaP/GaAs/GaAsBi HBT exhibits a higher collector current, a lower base-emitter (B–E) turn-on voltage, and a relatively lower collector-emitter offset voltage of only 7 mV. Because the more electrons stored in the base is further increased in the InGaP/GaAs/GaAsBi HBT, it introduces the collector current to increase and the B–E turn-on voltage to decrease for low input power applications. However, the current gain is slightlymore » smaller than the traditional InGaP/GaAs HBT attributed to the increase of base current for the minority carriers stored in the GaAsBi base.« less

  2. [Caloric intake in parenteral nutrition of very low weight infants].

    PubMed

    Maggio, L; Gallini, F; De Carolis, M P; Frezza, S; Greco, F

    1994-10-01

    To evaluate the efficacy of a measure able to compare energy intake from parenteral and enteral nutrition we documented growth patterns in a group of VLBW infants treated with parenteral nutrition (PN). To analyze comparative energy intake from the two sources we expressed a percentage of both parenteral and enteral calories: the former (RCP%) related to an optimal value of 85 non protein calories and the latter (RCE%) to an optimal value of 150 total calories. Total energy intake was planned on the RCT% (RCP% + RCE%). We studied 75 VLBW infants with a mean BW of 1040 g and a mean GA of 29.5 weeks. The mean duration of PN was 25.8 +/- 10.4 days. The initial weight loss (10.2 +/- 5.3%), the time to regain BW (5.5 +/- 4 days) and the day of lowest weight (5.2 +/- 1.6 day of life) were in the normal range; the subsequent growth rate resulted 25.9 +/- 9.2 g/kg/die and did not change for different GA or BW. Growth pattern about head circumference and length were above the third percentile. The mean age of RCT% = 100% was 11.4 +/- 4.8 days of PN; this value was higher for the more premature infants. Severe metabolic abnormalities were not detected. Our observations show the efficacy of the RCT% as index of energy from both enteral and parenteral source during PN: the growth pattern seems to be quite satisfactory without any severe metabolic complication.

  3. 28 CFR 543.11 - Legal research and preparation of legal documents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Legal research and preparation of legal... INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.11 Legal research and preparation of legal... program or work assignment), to do legal research and to prepare legal documents. Where practical, the...

  4. 28 CFR 543.11 - Legal research and preparation of legal documents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Legal research and preparation of legal... INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.11 Legal research and preparation of legal... program or work assignment), to do legal research and to prepare legal documents. Where practical, the...

  5. 28 CFR 543.11 - Legal research and preparation of legal documents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Legal research and preparation of legal... INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.11 Legal research and preparation of legal... program or work assignment), to do legal research and to prepare legal documents. Where practical, the...

  6. 28 CFR 543.11 - Legal research and preparation of legal documents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Legal research and preparation of legal... INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.11 Legal research and preparation of legal... program or work assignment), to do legal research and to prepare legal documents. Where practical, the...

  7. 28 CFR 543.11 - Legal research and preparation of legal documents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Legal research and preparation of legal... INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.11 Legal research and preparation of legal... program or work assignment), to do legal research and to prepare legal documents. Where practical, the...

  8. Biocompatibility of GaSb thin films grown by RF magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Nishimoto, Naoki; Fujihara, Junko; Yoshino, Katsumi

    2017-07-01

    GaSb may be suitable for biological applications, such as cellular sensors and bio-medical instrumentation because of its low toxicity compared with As (III) compounds and its band gap energy. Therefore, the biocompatibility and the film properties under physiological conditions were investigated for GaSb thin films with or without a surface coating. GaSb thin films were grown on quartz substrates by RF magnetron sputtering, and then coated with (3-mercaptopropyl) trimethoxysilane (MPT). The electrical properties, surface morphology, and crystal structure of the GaSb thin film were unaffected by the MPT coating. The cell viability assay suggested that MPT-coated GaSb thin films are biocompatible. Bare GaSb was particularly unstable in pH9 buffer. Ga elution was prevented by the MPT coating, although the Ga concentration in the pH 9 buffer was higher than that in the other solutions. The surface morphology and crystal structure were not changed by exposure to the solutions, except for the pH 9 buffer, and the thin film properties of MPT-coated GaSb exposed to distilled water and H2O2 in saline were maintained. These results indicate that MPT-coated GaSb thin films are biocompatible and could be used for temporary biomedical devices.

  9. Carrier Concentration Control of GaSb/GaInAsSb System

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

    Lazzari, J.-L.; Anda, F. de; Nieto, J.

    2007-02-22

    The residual carrier concentration of GaSb and GaSb-lattice matched Ga1-xInxAsySb1-y alloys (x = 0.12-0.26; y = 0.9x) grown by liquid phase epitaxy (LPE) and molecular beam epitaxy (MBE) was studied as a function of growth temperature, V/III ratio and alloy composition. Typical carrier concentrations p {approx} 2-3x1016 cm-3 were obtained for undoped GaSb grown by MBE at 480 deg. C, by LPE from Ga-rich melt at low temperature (400 deg. C), and by LPE from Sb-rich melts at {approx}600 deg. C. The native acceptor defect responsible of the high p-type residual doping in GaSb is reduced when the indium concentrationmore » is increased, and disappears for indium rich alloys (x = 0.23, 0.26). Tellurium compensation was used for controlled n-type doping in the (0.05-30)x1017 cm-3 range. A maximum of free carrier concentration was 1.5x1018 cm-3 for LPE layers, 2x1018 cm-3 for MBE layers grown at 1.0 {mu}m/h, 3.5x1018 cm-3 for MBE layers grown at 0.2 {mu}m/h. SIMS measurements showed Te concentrations of more than 1020 at/cm3, suggesting the formation of ternary GaSb1-xTex solid solution.« less

  10. Legal Services: The Army Legal Assistance Program

    DTIC Science & Technology

    1996-02-21

    Army Regulation 27–3 Legal Services The Army Legal Assistance Program Headquarters Department of the Army Washington, DC 21 February 1996 REPORT...1996 to xx-xx-1996 4. TITLE AND SUBTITLE The Army Legal Assistance Program Unclassified 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...Z39.18 SUMMARY of CHANGE AR 27–3 The Army Legal Assistance Program This change 2 corrects the title page of this regulation. This change 2-- o Corrects

  11. On the effect of N-GaN/P-GaN/N-GaN/P-GaN/N-GaN built-in junctions in the n-GaN layer for InGaN/GaN light-emitting diodes.

    PubMed

    Kyaw, Zabu; Zhang, Zi-Hui; Liu, Wei; Tan, Swee Tiam; Ju, Zhen Gang; Zhang, Xue Liang; Ji, Yun; Hasanov, Namig; Zhu, Binbin; Lu, Shunpeng; Zhang, Yiping; Sun, Xiao Wei; Demir, Hilmi Volkan

    2014-01-13

    N-GaN/P-GaN/N-GaN/P-GaN/N-GaN (NPNPN-GaN) junctions embedded between the n-GaN region and multiple quantum wells (MQWs) are systematically studied both experimentally and theoretically to increase the performance of InGaN/GaN light emitting diodes (LEDs) in this work. In the proposed architecture, each thin P-GaN layer sandwiched in the NPNPN-GaN structure is completely depleted due to the built-in electric field in the NPNPN-GaN junctions, and the ionized acceptors in these P-GaN layers serve as the energy barriers for electrons from the n-GaN region, resulting in a reduced electron over flow and enhanced the current spreading horizontally in the n- GaN region. These lead to increased optical output power and external quantum efficiency (EQE) from the proposed device.

  12. Heterologous, Expression, and Characterization of Thermostable Glucoamylase Derived from Aspergillus flavus NSH9 in Pichia pastoris

    PubMed Central

    Karim, Kazi Muhammad Rezaul; Hossain, Md. Anowar; Sing, Ngieng Ngui; Mohd Sinang, Fazia; Hussain, Mohd Hasnain Md.; Roslan, Hairul Azman

    2016-01-01

    A novel thermostable glucoamylase cDNA without starch binding domain (SBD) of Aspergillus flavus NSH9 was successfully identified, isolated, and overexpressed in Pichia pastoris GS115. The complete open reading frame of glucoamylase from Aspergillus flavus NSH9 was identified by employing PCR that encodes 493 amino acids lacking in the SBD. The first 17 amino acids were presumed to be a signal peptide. The cDNA was cloned into Pichia pastoris and the highest expression of recombinant glucoamylase (rGA) was observed after 8 days of incubation period with 1% methanol. The molecular weight of the purified rGA was about 78 kDa and exhibited optimum catalytic activity at pH 5.0 and temperature of 70°C. The enzyme was stable at higher temperature with 50% of residual activity observed after 20 min at 90°C and 100°C. Low concentration of metal (Mg++, Fe++, Zn++, Cu++, and Pb++) had positive effect on rGA activity. This rGA has the potential for use and application in the saccharification steps, due to its thermostability, in the starch processing industries. PMID:27504454

  13. Ga2O3 and GaN nanocrystalline film: reverse micelle assisted solvothermal synthesis and characterization.

    PubMed

    Sinha, Godhuli; Ganguli, Dibyendu; Chaudhuri, Subhadra

    2008-03-01

    Gallium oxide (beta-Ga2O3) nanoparticles were successfully deposited on quartz glass substrates using sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/n-hexane/ethylene glycol monomethyl ether (EGME) reverse micelle-mediated solvothermal process with different omega values. The mean diameter of Ga2O3 particles was approximately 2-3 nm and found to be approximately independent of omega values of the reverse micelles. However, when the Ga2O3 nanocrystalline films were nitrided at 900 degrees C under flowing NH3 atmosphere for 1 h, the mean diameter of the resulted gallium nitride (wurtzite-GaN) nanoparticles varied from 3-9 nm. Both nanocrystalline films of Ga2O3 and GaN were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, UV-vis spectroscopy and photoluminescence in order to study their chemical and physical properties explicitly.

  14. Growth and electrical transport properties of InGaN/GaN heterostructures grown by PAMBE

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

    Sinha, Neeraj; Department of Materials Science, Gulbarga University, Gulbarga 585106; Roul, Basanta, E-mail: basantaroul@gmail.com

    2015-01-15

    Highlights: • InGaN thin films were grown on GaN template by PAMBE. • InGaN films were characterized by HRXRD, SEM and PL and Raman spectroscopy. • The indium incorporation in single phase InGaN films was found to be 23%. • The I–V characteristic of the InGaN/GaN heterojunction shows rectifying behavior. • Log–log plot of the I–V characteristics indicates the presence of SCLC mechanism. - Abstract: InGaN epitaxial films were grown on GaN template by plasma-assisted molecular beam epitaxy. The composition of indium incorporation in single phase InGaN film was found to be 23%. The band gap energy of single phasemore » InGaN was found to be ∼2.48 eV. The current–voltage (I–V) characteristic of InGaN/GaN heterojunction was found to be rectifying behavior which shows the presence of Schottky barrier at the interface. Log–log plot of the I–V characteristics under forward bias indicates the current conduction mechanism is dominated by space charge limited current mechanism at higher applied voltage, which is usually caused due to the presence of trapping centers. The room temperature barrier height and the ideality factor of the Schottky junction were found to 0.76 eV and 4.9 respectively. The non-ideality of the Schottky junction may be due to the presence of high pit density and dislocation density in InGaN film.« less

  15. The central zone has increased 68Ga-PSMA-11 uptake: "Mickey Mouse ears" can be hot on 68Ga-PSMA-11 PET.

    PubMed

    Pizzuto, Daniele A; Müller, Julian; Mühlematter, Urs; Rupp, Niels J; Töpfer, Antonia; Mortezavi, Ashkan; Nagel, Hannes; Kranzbühler, Benedikt; Eberli, Daniel; Burger, Irene A

    2018-03-09

    Given the good correlation between PSMA expression and intraglandular tumour aggressiveness based on immunohistochemistry, there is increasing interest in 68 Ga-PSMA-11 PET/MRI for staging prostate cancer (PCA). Therefore, accurate knowledge of prostate anatomy as well as normal distribution of PSMA within the prostate gland is becoming essential. The aim of this study was to investigate the physiological intraprostatic distribution of 68 Ga-PSMA-11. We retrospectively analysed all patients who underwent a staging 68 Ga-PSMA-11 PET/MRI scan between June 2016 and January 2018 for high-risk PCA, underwent radical prostatectomy in our institution, and gave written consent for further data analysis. In each patient, standardized volumes of interest (VOIs) were placed bilaterally in the central, transition and peripheral zones within the zonal anatomy according to T2 weighted sequences in the axial and coronal planes. VOIs were only placed if they were safely within healthy tissue without spillover from the PCA. SUV max and SUV mean were determined and their differences among the regions were assessed using the Wilcoxon signed-ranks test. Of 283 consecutive patients scanned with 68 Ga-PSMA-11 PET/MR, 31 were analysed. A total of 133 VOIs were placed, 46 in the central zone, 41 in the transition zone and 46 in the peripheral zone. Differences in SUV max between the central zone (mean 3.9 ± 0.58) and transition zone (mean 3.2 ± 0.59) and between the central zone and peripheral zone (mean 2.7 ± 0.54) were statistically significant (both p < 0.001). Our results suggest that higher 68 Ga-PSMA-11 accumulation in the central zone than in the transition and peripheral zones is normal, and leads to a pattern resembling "Mickey Mouse ears" on 68 Ga-PSMA-11 PET. This pattern could be helpful in avoiding false-positive interpretations of PET scans.

  16. Impact ionisation in Al0.9Ga0.1As0.08Sb0.92 for Sb-based avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Collins, X.; Craig, A. P.; Roblin, T.; Marshall, A. R. J.

    2018-01-01

    We report the impact ionisation coefficients of the quaternary alloy Al0.9Ga0.1As0.08Sb0.92 lattice matched to GaSb substrates within the field range of 150 to 550 kV cm-1 using p-i-n and n-i-p diodes of various intrinsic thicknesses. The coefficients were found with an evolutionary fitting algorithm using a non-local recurrence based multiplication model and a variable electric field profile. These coefficients indicate that an avalanche photodiode not only can be designed to be a function in the mid-wave infrared but also can be operated at lower voltages. This is due to the high magnitude of the impact ionisation coefficients at relatively low fields compared to other III-V materials typically used in avalanche multiplication regions.

  17. Effects of phase transformation on the microstructures and magnetostriction of Fe-Ga and Fe-Ga-Zn ferromagnetic shape memory alloys

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

    Lin, Yin-Chih, E-mail: lin3312@cc.kuas.edu.tw; Lin, Chien-Feng

    2015-05-07

    The phase transformation and magnetostriction of bulk Fe{sub 73}Ga{sub 27} and Fe{sub 73}Ga{sub 18}Zn{sub 9} (at. %) ferromagnetic shape memory alloys (FSMs) were investigated by transmission electron microscopy (TEM), x-ray diffraction (XRD), and a magnetostrictive-meter setup. For the Fe{sub 73}Ga{sub 27} FSM alloy solution treated at 1100 °C for 4 h and quenched in ice brine, the antiphase boundary segments of the D0{sub 3} domain were observed in the A2 (disordered) matrix, and the Fe{sub 73}Ga{sub 27} FSM alloy had an optimal magnetostriction (λ{sub ‖}{sup s }= 71 × 10{sup −6} and λ{sub ⊥}{sup s }= −31 × 10{sup −6}). In Fe{sub 73}Ga{sub 27} FSM alloy as-quenched, aged at 700 °C formore » 24 h, and furnace cooled, D0{sub 3} nanoclusters underwent phase transformation to an intermediate tetragonal phase (i.e., L1{sub 0}-like martensite) via Bain distortion, and finally L1{sub 2} (Fe{sub 3}Ga) structures precipitated, as observed by TEM and XRD. The L1{sub 0}-like martensite and L1{sub 2} phases in the aged Fe{sub 73}Ga{sub 27} FSM alloy drastically decreased the magnetostriction from positive to negative (λ{sub ‖}{sup s }= −20 × 10{sup −6} and λ{sub ⊥}{sup s }= −8 × 10{sup −6}). However, in Fe{sub 73}Ga{sub 18}Zn{sub 9} FSM alloy as-quenched and aged, the phase transformation of D0{sub 3} to an intermediate tetragonal martensite phase and precipitation of L1{sub 2} structures were not found. The results indicate that the aged Fe{sub 73}Ga{sub 18}Zn{sub 9} FSM alloy maintained stable magnetostriction (λ{sub ‖}{sup s }= 36 × 10{sup −6} and λ{sub ⊥}{sup s }= −31 × 10{sup −6}). Adding Zn can improve the ferromagnetic shape memory effect of aged Fe{sub 73}Ga{sub 18}Zn{sub 9} alloy, which may be useful in application of the alloy in high temperature environments.« less

  18. 32 CFR 727.9 - Referrals to civilian lawyers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Referrals to civilian lawyers. 727.9 Section 727.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL LEGAL ASSISTANCE § 727.9 Referrals to civilian lawyers. (a) General. If it is determined that the legal assistance...

  19. Synthesis of mesoporous β-Ga2O3 nanorods using PEG as template: preparation, characterization and photocatalytic properties.

    PubMed

    Zhao, Weirong; Yang, Yong; Hao, Rui; Liu, Feifei; Wang, Yan; Tan, Min; Tang, Jing; Ren, Daqing; Zhao, Dongye

    2011-09-15

    Mesoporous wide bandgap semiconductors offer high photocatalytic oxidation and mineralization activities. In this study, mesoporous β-Ga(2)O(3) diamond nanorods with 200-300 nm in diameter and 1.0-1.2 μm in length were synthesized via a urea-based hydrothermal method using polyethylene glycol (PEG) as template agent. The UV photocatalytic oxidation activity of β-Ga(2)O(3) for gaseous toluene was evaluated, and 7 kinds of intermediates were monitored online by a proton transfer reaction mass spectrometry. Photoluminescence spectra manifested that the dosage and molecular weight of PEG are crucial for formation of vacancies and photocatalytic oxidation activities. A PEG-assisted hydrothermal formation mechanism of mesoporous β-Ga(2)O(3) diamond nanorods was proposed. Based on the health risk influence index (η) of the intermediates, the calculated health risks revealed that the β-Ga(2)O(3) nanorods with a η value of 9.6 are much safer than TiO(2) (η = 17.6). Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Pressure-Induced Valence Crossover and Novel Metamagnetic Behavior near the Antiferromagnetic Quantum Phase Transition of YbNi3Ga9

    NASA Astrophysics Data System (ADS)

    Matsubayashi, K.; Hirayama, T.; Yamashita, T.; Ohara, S.; Kawamura, N.; Mizumaki, M.; Ishimatsu, N.; Watanabe, S.; Kitagawa, K.; Uwatoko, Y.

    2015-02-01

    We report electrical resistivity, ac magnetic susceptibility, and x-ray absorption spectroscopy measurements of intermediate valence YbNi3Ga9 under pressure and magnetic field. We have revealed a characteristic pressure-induced Yb valence crossover within the temperature-pressure phase diagram, and a first-order metamagnetic transition is found below Pc˜9 GPa where the system undergoes a pressure-induced antiferromagnetic transition. As a possible origin of the metamagnetic behavior, a critical valence fluctuation emerging near the critical point of the first-order valence transition is discussed on the basis of the temperature-field-pressure phase diagram.

  1. Study on the Electronic Transport Properties of Zigzag GaN Nanotubes

    NASA Astrophysics Data System (ADS)

    Li, Enling; Wang, Xiqiang; Hou, Liping; Zhao, Danna; Dai, Yuanbin; Wang, Xuewen

    2011-02-01

    The electronic transport properties of zigzag GaN nanotubes (n, 0) (4 <= n <= 9) have been calculated using the density functional theory and non-equilibrium Green's functions method. Firstly, the density functional theory (DFT) is used to optimize and calculate the electronic structure of GaNNTs (n, 0) (4<=n<=9). Secondly, DFT and non-equilibrium Green function (NEGF) method are also used to predict the electronic transport properties of GaNNTs two-probe system. The results showed: there is a corresponding relation between the electronic transport properties and the valley of state density of each GaNNT. In addition, the volt-ampere curve of GaNNT is approximately linear.

  2. Cannabis and Δ9-tetrahydrocannabinol (THC) for weight loss?

    PubMed

    Le Foll, Bernard; Trigo, Jose M; Sharkey, Keith A; Le Strat, Yann

    2013-05-01

    Obesity is one of the highest preventable causes of morbidity and mortality in the developed world [1]. It has been well known for a long time that exposure to cannabis produces an increase of appetite (a phenomenon referred to as the 'munchies'). This phenomenon led to an exploration of the role of the endocannabinoid system in the regulation of obesity and associated metabolic syndrome. This effort subsequently led to the development of a successful therapeutic approach for obesity that consisted of blocking the cannabinoid CB1 receptors using ligands such as Rimonabant in order to produce weight loss and improve metabolic profile [2]. Despite being efficacious, Rimonabant was associated with increased rates of depression and anxiety and therefore removed from the market. We recently discovered that the prevalence of obesity is paradoxically much lower in cannabis users as compared to non-users and that this difference is not accounted for by tobacco smoking status and is still present after adjusting for variables such as sex and age. Here, we propose that this effect is directly related to exposure to the Δ(9)-tetrahydrocannabinol (THC) present in cannabis smoke. We therefore propose the seemingly paradoxical hypothesis that THC or a THC/cannabidiol combination drug may produce weight loss and may be a useful therapeutic for the treatment of obesity and its complications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Shubnikov-de Haas measurements of the 2-D electron gas in pseudomorphic In(0.1)Ga(0.9)As grown on GaAs

    NASA Technical Reports Server (NTRS)

    Szydlic, P. P.; Alterovitz, S. A.; Haugland, E. J.; Segall, B.; Henderson, T. S.

    1988-01-01

    Shubnikov-de Hass (SdH) measurements performed on a 200 A layer of pseudomorphic In(0.10)Ga(0.90)As grown by MBE on undoped GaAs with an overlayer of Al(0.15)Ga(0.85)As are presented. These measurements were performed in magnetic fields up to 1.4 tesla at T in the range of 1.4-10 K. It was found that only one subband was populated with a density of 5.8 x 10 to the 11/cm-squared and an effective mass at the Fermi level m(asterisk) = (0.060 + or - 0.001)m(0).

  4. Three-year weight change in successful weight losers who lost weight on a low-carbohydrate diet.

    PubMed

    Phelan, Suzanne; Wyatt, Holly; Nassery, Shirine; Dibello, Julia; Fava, Joseph L; Hill, James O; Wing, Rena R

    2007-10-01

    The purpose of this study was to evaluate long-term weight loss and eating and exercise behaviors of successful weight losers who lost weight using a low-carbohydrate diet. This study examined 3-year changes in weight, diet, and physical activity in 891 subjects (96 low-carbohydrate dieters and 795 others) who enrolled in the National Weight Control Registry between 1998 and 2001 and reported >or=30-lb weight loss and >or=1 year weight loss maintenance. Only 10.8% of participants reported losing weight after a low-carbohydrate diet. At entry into the study, low-carbohydrate diet users reported consuming more kcal/d (mean +/- SD, 1,895 +/- 452 vs. 1,398 +/- 574); fewer calories in weekly physical activity (1,595 +/- 2,499 vs. 2,542 +/- 2,301); more calories from fat (64.0 +/- 7.9% vs. 30.9 +/- 13.1%), saturated fat (23.8 +/- 4.1 vs. 10.5 +/- 5.2), monounsaturated fat (24.4 +/- 3.7 vs. 11.0 +/- 5.1), and polyunsaturated fat (8.6 +/- 2.7 vs. 5.5 +/- 2.9); and less dietary restraint (10.8 +/- 2.9 vs. 14.9 +/- 3.9) compared with other Registry members. These differences persisted over time. No differences in 3-year weight regain were observed between low-carbohydrate dieters and other Registry members in intent-to-treat analyses (7.0 +/- 7.1 vs. 5.7 +/- 8.7 kg). It is possible to achieve and maintain long-term weight loss using a low-carbohydrate diet. The long-term health effects of weight loss associated with a high-fat diet and low activity level merits further investigation.

  5. Mathematics Deficiencies in Children with Very Low Birth Weight or Very Preterm Birth

    ERIC Educational Resources Information Center

    Taylor, H. Gerry; Espy, Kimberly Andrews; Anderson, Peter J.

    2009-01-01

    Children with very low birth weight (VLBW, less than 1500 g) or very preterm birth (VPTB, less than 32 weeks gestational age or GA) have more mathematics disabilities or deficiencies (MD) and higher rates of mathematics learning disabilities (MLD) than normal birth weight term-born children (NBW, greater than 2500 g and greater than 36 weeks GA).…

  6. Comparison of blue-green response between transmission-mode GaAsP- and GaAs-based photocathodes grown by molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Gang-Cheng, Jiao; Zheng-Tang, Liu; Hui, Guo; Yi-Jun, Zhang

    2016-04-01

    In order to develop the photodetector for effective blue-green response, the 18-mm-diameter vacuum image tube combined with the transmission-mode Al0.7Ga0.3As0.9 P 0.1/GaAs0.9 P 0.1 photocathode grown by molecular beam epitaxy is tentatively fabricated. A comparison of photoelectric property, spectral characteristic and performance parameter between the transmission-mode GaAsP-based and blue-extended GaAs-based photocathodes shows that the GaAsP-based photocathode possesses better absorption and higher quantum efficiency in the blue-green waveband, combined with a larger surface electron escape probability. Especially, the quantum efficiency at 532 nm for the GaAsP-based photocathode achieves as high as 59%, nearly twice that for the blue-extended GaAs-based one, which would be more conducive to the underwater range-gated imaging based on laser illumination. Moreover, the simulation results show that the favorable blue-green response can be achieved by optimizing the emission-layer thickness in a range of 0.4 μm-0.6 μm. Project supported by the National Natural Science Foundation of China (Grant No. 61301023) and the Science and Technology on Low-Light-Level Night Vision Laboratory Foundation, China (Grant No. BJ2014001).

  7. Legal considerations during pediatric emergency mass critical care events.

    PubMed

    Courtney, Brooke; Hodge, James G

    2011-11-01

    Recent public health emergencies, such as the 2009 Influenza A/H1N1 Pandemic and Hurricane Katrina, underscore the importance of developing healthcare response plans and protocols for disasters impacting large populations. Significant research and scholarship, including the 2009 Institute of Medicine report on crisis standards of care and the 2008 Task Force for Mass Critical Care recommendations, provide guidance for healthcare responses to catastrophic emergencies. Most of these efforts recognize but do not focus on the unique needs of pediatric populations. In 2008, the Centers for Disease Control and Prevention supported the formation of a task force to address pediatric emergency mass critical care response issues, including legal issues. Liability is a significant concern for healthcare practitioners and facilities during pediatric emergency mass critical care that necessitates a shift to crisis standards of care. This article describes the legal considerations inherent in planning for and responding to catastrophic health emergencies and makes recommendations for pediatric emergency mass critical care legal preparedness. The Pediatric Emergency Mass Critical Care Task Force, composed of 36 experts from diverse public health, medical, and disaster response fields, convened in Atlanta, GA, on March 29-30, 2010, to review the pediatric emergency mass critical care recommendations developed by a 17-member steering committee. During the meeting, experts determined that the recommendations would be strengthened by a manuscript addressing legal issues. Authors drafted the manuscript through consensus-based study of peer-reviewed research, literature reviews, and expert opinion. The manuscript was reviewed by Pediatric Emergency Mass Critical Care Steering Committee members and additional legal counsel and revised. While the legal issues associated with providing pediatric emergency mass critical care are not unique within the overall context of disaster healthcare

  8. Growth and structure of In{sub 0.5}Ga{sub 0.5}Sb quantum dots on GaP(001)

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

    Sala, E. M.; Stracke, G.; Schlichting, S.

    2016-09-05

    Stranski-Krastanov (SK) growth of In{sub 0.5}Ga{sub 0.5}Sb quantum dots (QDs) on GaP(001) by metalorganic vapor phase epitaxy is demonstrated. A thin GaAs interlayer prior to QD deposition enables QD nucleation. The impact of a short Sb-flush before supplying InGaSb is investigated. QD growth gets partially suppressed for GaAs interlayer thicknesses below 6 monolayers. QD densities vary from 5 × 10{sup 9} to 2 × 10{sup 11} cm{sup −2} depending on material deposition and Sb-flush time. When In{sub 0.5}Ga{sub 0.5}Sb growth is carried out without Sb-flush, the QD density is generally decreased, and up to 60% larger QDs are obtained.

  9. Legal Officer Civil Law Study Guide

    DTIC Science & Technology

    1993-04-01

    Publication 9-7 Civil Law - Legal Officer Study Guide 2. Some cases are not amenable to treatment (such as extrafamilial pedophiles , who are considered...evaluations showing a good treatment prognosis (including a determination that the person is not a pedophile , as pedophiles are generally considered

  10. Two new phases in the ternary RE-Ga-S systems with the unique interlinkage of GaS4 building units: synthesis, structure, and properties.

    PubMed

    Lin, Hua; Shen, Jin-Ni; Zhu, Wei-Wei; Liu, Yi; Wu, Xin-Tao; Zhu, Qi-Long; Wu, Li-Ming

    2017-10-17

    Two novel ternary rare-earth chalcogenides, Yb 6 Ga 4 S 15 and Lu 5 GaS 9 , have been prepared by solid-state reactions of an elemental mixture at high temperatures. Their structures were determined on the basis of single-crystal X-ray diffraction. Yb 6 Ga 4 S 15 crystallizes in the monoclinic space group C2/m (no.12) [a = 23.557(2) Å, b = 3.7664(4) Å, c = 12.466(1) Å, β = 90.915(9)°, V = 1105.9(2) Å 3 and Z = 2], whereas Lu 5 GaS 9 crystallizes in the triclinic space group P1[combining macron] (no.2) [a = 7.735(3) Å, b = 10.033(4) Å, c = 10.120(4) Å, α = 106.296(4)°, β = 100.178(5)°, γ = 101.946(3)°, V = 714.1(5) Å 3 and Z = 2]. Both the structures feature complicated three dimensional frameworks with the unique interlinkages of GaS 4 as basic building units. Significantly, photo-electrochemical measurements indicated that title compounds were photoresponsive under visible-light illumination. Furthermore, the UV-visible-near IR diffuse reflectance spectra, thermal stabilities, electronic structures, physical properties as well as a structure change trend of the ternary rare-earth/gallium/sulfur compounds have been evaluated.

  11. Multibias and thermal behavior of microwave GaN and GaAs based HEMTs

    NASA Astrophysics Data System (ADS)

    Alim, Mohammad A.; Rezazadeh, Ali A.; Gaquiere, Christophe

    2016-12-01

    Multibias and thermal characterizations on 0.25 μm × (2 × 100) μm AlGaN/GaN/SiC HEMT and 0.5 μm × (2 × 100) μm AlGaAs/InGaAs pseudomorphic HEMT have carried out for the first time. Two competitive device technologies are investigated with the variations of bias and temperature in order to afford a detailed realization of their potentialities. The main finding includes the self heating effect in the GaN device, zero temperature coefficient points at the drain current and transconductance in the GaAs device. The thermal resistance RTH of 7.1, 8.2 and 9.4 °C mm/W for the GaN device was estimated at 25, 75 and 150 °C respectively which are consistent with those found in the open literature. The temperature trend of the threshold voltage VT, Schottky barrier height ϕb, sheet charge densities of two dimensional electron gas ns, and capacitance under the gate Cg are exactly opposite in the two devices; whereas the knee voltage Vk, on resistance Ron, and series resistance Rseries are shows similar trend. The multi-bias and thermal behavior of the output current Ids, output conductance gds, transconductance gm, cut-off frequency ft, maximum frequency fmax, effective velocity of electron, veff and field dependent mobility, μ demonstrates a great potential of GaN device. These results provide some valuable insights for technology of preference for future and current applications.

  12. Public perceptions of arguments supporting and opposing recreational marijuana legalization.

    PubMed

    McGinty, Emma E; Niederdeppe, Jeff; Heley, Kathryn; Barry, Colleen L

    2017-06-01

    In debates about recreational marijuana legalization, pro-legalization arguments highlighting economic and other potential policy benefits compete with anti-legalization arguments emphasizing public health risks. In 2016, we conducted a national survey using an online panel (N=979) designed to answer two main research questions: (1) How do Americans perceive the relative strength of competing arguments about recreational marijuana legalization? (2) How are perceptions of argument strength associated with public support for recreational marijuana legalization? We examined differences in attitudes among individuals living in states that have/have not legalized recreational marijuana and among Democrats/Independents/Republicans. Ordered logit regression assessed the relationship between perceived argument strength and public support for recreational marijuana legalization. Respondents rated pro-legalization arguments highlighting beneficial economic and criminal justice consequences as more persuasive than anti-legalization arguments emphasizing adverse public health effects. Respondents were more likely to agree with arguments highlighting legalization's potential to increase tax revenue (63.9%) and reduce prison overcrowding (62.8%) than arguments emphasizing negative consequences on motor vehicle crashes (51.8%) and youth health (49.6%). The highest rated anti-legalization arguments highlighted the conflict between state and federal marijuana laws (63.0%) and asserted that legalization will fail to eliminate the black market (57.2%). Respondents who endorsed pro-legalization economic and criminal justice arguments were more likely than other respondents to support legalization. Our findings indicate that, on both side of the recreational marijuana legalization debate, there are arguments that resonate with the American public. However, public health risk messages were viewed as less compelling than pro-legalization economic and criminal justice-oriented arguments

  13. Highly efficient X-range AlGaN/GaN power amplifier

    NASA Astrophysics Data System (ADS)

    Tural'chuk, P. A.; Kirillov, V. V.; Osipov, P. E.; Vendik, I. B.; Vendik, O. G.; Parnes, M. D.

    2017-09-01

    The development of microwave power amplifiers (PAs) based on transistors with an AlGaN/GaN heterojunction are discussed in terms of the possible enhancement of their efficiency. The main focus is on the synthesis of the transforming circuits, which ensure the reactive load at the second- and third-harmonic frequencies and complex impedance at the fundamental frequency. This makes it possible to optimize the complex operation mode of a PA; i.e., to reduce the scattering power and enhance the efficiency. A microwave PA based on the Schottky-barrier-gate field-effect transistor with 80 electrodes based on the GaN pHEMT transistor with a gate length of 0.25 nm and a gate width of 125 nm is experimentally investigated. The amplifier has a pulse output power of 35 W and a power-added efficiency of at least 50% at a working frequency of 9 GHz.

  14. Survival of the very-low-birth-weight infants after cardiopulmonary resuscitation in neonatal intensive care unit.

    PubMed

    Kostelanetz, Anna S; Dhanireddy, Ramasubbareddy

    2004-05-01

    To assess whether advances in neonatal care in the last decade have altered the outcome of very-low-birth-weight (VLBW) infants after cardiopulmonary resuscitation (CPR) in the neonatal intensive care unit (NICU). Medical records of all VLBW infants (n=283, body weight (BW)=1066+/-281 g, gestational age (GA)=28.3+/-2.9 weeks) admitted to the NICU between 1999 and 2002 were reviewed. In all, 29 (10.25%) infants received CPR in the NICU. Only one of these infants survived. After adjusting for GA, the clinical variables significantly associated with the need for CPR in the NICU were (adjusted odds ratio; 95% CI): pulmonary hemorrhage (7.89; 3.06 to 20.28), pulmonary air leak syndrome (23.90; 7.58 to 75.4), and delivery by Cesarian section (0.26; 0.1 to 0.66). The results were similar when the data were reanalyzed matching the 28 infants in the CPR group with 28 infants of identical GA in the non-CPR group. Survival rate for the infants who require CPR in the NICU remains extremely poor. This poor outcome needs to be discussed with parents and the option of the "do not resuscitate" (DNR) order may be appropriate for these infants, especially for those infants with multiple organ failure unresponsive to therapy.

  15. Substitutional and interstitial oxygen in wurtzite GaN

    NASA Astrophysics Data System (ADS)

    Wright, A. F.

    2005-11-01

    Density-functional theory was used to compute energy-minimum configurations and formation energies of substitutional and interstitial oxygen (O) in wurtzite GaN. The results indicate that O substituted at a N site (ON) acts as a single donor with the ionized state (ON+1) being the most stable O state in p-type GaN. In n-type GaN, interstitial O (OI) is predicted to be a double acceptor and O substituted at a Ga site (OGa) is predicted to be a triple acceptor. The formation energies of these two species are comparable to that of ON in n-type GaN and, as such, they should form and compensate the ON donors. The extent of compensation was estimated for both Ga-rich and N-rich conditions with a total O concentration of 1017cm-3. Ga-rich conditions yielded negligible compensation and an ON concentration in excess of 9.9×1016cm-3. N-rich conditions yielded a 25% lower ON concentration, due to the increased stability of OI and OGa relative to ON, and moderate compensation. These findings are consistent with experimental results indicating that O acts as a donor in GaN(O). Complexes of ON with the Mg acceptor and OI with the Si donor were examined. Binding energies for charge-conserving reactions were ⩾0.5eV, indicating that these complexes can exist in equilibrium at room temperature. Complexes of ON with the Ga vacancy in n-type GaN were also examined and their binding energies were 1.2 and 1.4eV, indicating that appreciable concentrations can exist in equilibrium even at elevated temperatures.

  16. Strong ferromagnetic proximity polarization in ferromagnetic metal MnGa/n-type GaAs quantum well junction

    NASA Astrophysics Data System (ADS)

    Ji, Xiaochen; Shen, Chao; Wu, Yuanjun; Lu, Jun; Zhao, Jianhua; Zheng, Houzhi

    2017-11-01

    By biasing a ferromagnetic metal MnGa/10 nm-thick, n-type GaAs quantum well (QW) junction from negative to positive, it is found that its spin dynamics at zero magnetic field is composed of two components with opposite signs. One is excited by a circularly polarized pump beam. The other is induced by ferromagnetic proximity polarization (FPP), which is continuously enhanced as the bias increases towards the positive direction. The time-resolved Kerr rotations have also been measured at a magnetic field of 0.9 Tesla. A phase reversion of Larmor precession is observed as the bias passes through  +0.5 V. Following simple quantum mechanics, we become aware of the fact that the transmission and reflection rates of electrons at the interface of MnGa/n-type GaAs QW are enhanced by a factor of ν , which is the attempting frequency of electron onto a ferromagnet/semiconductor interface. That gives a reasonable explanation why the FPP effect in our MnGa/n-type GaAs QW junction is greatly enhanced as biasing it into forward direction.

  17. Laser Induced Electrodeposition on Polyimide and GaAs Substrates

    DTIC Science & Technology

    1983-10-01

    6 3.1 Laser Gold Plating on Undoped Ga As Substrate ........... 6 3.1.1 Deposit Formation...22 iv LIST OF ILLUSTRATIONS Figure Page 1. Experimental Set-Up . . . . . .................. 4 2. Laser Gold Pla’ting Undoped GaAs (100...9 3. Laser Gold Plating Undoped GaAs (100) Deposit Resistance Measurement ......................... .10 4. Laser Gold Plating on Polyimide

  18. Prospective Evaluation of 68Ga-RM2 PET/MRI in Patients with Biochemical Recurrence of Prostate Cancer and Negative Findings on Conventional Imaging.

    PubMed

    Minamimoto, Ryogo; Sonni, Ida; Hancock, Steven; Vasanawala, Shreyas; Loening, Andreas; Gambhir, Sanjiv S; Iagaru, Andrei

    2018-05-01

    68 Ga-labeled DOTA-4-amino-1-carboxymethyl-piperidine-d-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 ( 68 Ga-RM2) is a synthetic bombesin receptor antagonist that targets gastrin-releasing peptide receptor (GRPr). GRPr proteins are highly overexpressed in several human tumors, including prostate cancer (PCa). We present data from the use of 68 Ga-RM2 in patients with biochemical recurrence (BCR) of PCa and negative findings on conventional imaging. Methods: We enrolled 32 men with BCR of PCa, who were 59-83 y old (mean ± SD, 68.7 ± 6.4 y). Imaging started at 40-69 min (mean, 50.5 ± 6.8 min) after injection of 133.2-151.7 MBq (mean, 140.6 ± 7.4 MBq) of 68 Ga-RM2 using a time-of-flight-enabled simultaneous PET/MRI scanner. T1-weighted, T2-weighted, and diffusion-weighted images were acquired. Results: All patients had a rising level of prostate-specific antigen (PSA) (range, 0.3-119.0 ng/mL; mean, 10.1 ± 21.3 ng/mL) and negative findings on conventional imaging (CT or MRI, and a 99m Tc-methylene diphosphonate bone scan) before enrollment. The observed 68 Ga-RM2 PET detection rate was 71.8%. 68 Ga-RM2 PET identified recurrent PCa in 23 of the 32 participants, whereas the simultaneous MRI scan identified findings compatible with recurrent PCa in 11 of the 32 patients. PSA velocity was 0.32 ± 0.59 ng/mL/y (range, 0.04-1.9 ng/mL/y) in patients with negative PET findings and 2.51 ± 2.16 ng/mL/y (range, 0.13-8.68 ng/mL/y) in patients with positive PET findings ( P = 0.006). Conclusion: 68 Ga-RM2 PET can be used for assessment of GRPr expression in patients with BCR of PCa. High uptake in multiple areas compatible with cancer lesions suggests that 68 Ga-RM2 is a promising PET radiopharmaceutical for localization of disease in patients with BCR of PCa and negative findings on conventional imaging. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

  19. Lightweight, Light-Trapped, Thin GaAs Solar Cells for Spacecraft Applications.

    DTIC Science & Technology

    1995-10-05

    improve the efficiency of this type of cell. 2 The high efficiency and light weight of the cover glass supported GaAs solar cell can have a significant...is a 3-mil cover glass and 1-mil silicone adhesive on the front surface of the GaAs solar cell. Power Output 3000 400 -{ 2400 { N 300 S18200 W/m2...the ultra-thin, light-trapped GaAs solar ceill 3. Incorporate light trapping. 0 external quantum efficiency at 850 nm increased by 5.2% 4. Develop

  20. What is legal medicine--are legal and forensic medicine the same?

    PubMed

    Beran, Roy G

    2010-04-01

    Some consider the terms "forensic" and "legal" medicine to be synonymous but this is counter to the title of the Faculty of Forensic and Legal Medicine or the dual strands for progression to fellowship of the Australian College of Legal Medicine. The paper examines a very brief historical background to legal medicine and develops a definition of the strands thereof, namely legal and forensic medicine. It demonstrates that the two are different components of the application of medical knowledge upon the legal system. Legal medicine has greater relevance to civil and tort law, impacting upon patient care, whereas forensic medicine relates to criminal law and damage to, or by, patients.

  1. Comparison of trap characteristics between AlGaN/GaN and AlGaN/InGaN/GaN heterostructure by frequency dependent conductance measurement

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

    Chakraborty, Apurba, E-mail: apurba.chakraborty86@gmail.com; Biswas, Dhrubes; Advanced Technology Development Centre, IIT Kharagpur, Kharagpur 721302

    2015-02-23

    Frequency dependent conductance measurement is carried out to observe the trapping effect in AlGaN/InGaN/GaN double heterostructure and compared that with conventional AlGaN/GaN single heterostructure. It is found that the AlGaN/InGaN/GaN diode structure does not show any trapping effect, whereas single heterostructure AlGaN/GaN diode suffers from two kinds of trap energy states in near depletion to higher negative voltage bias region. This conductance behaviour of AlGaN/InGaN/GaN heterostructure is owing to more Fermi energy level shift from trap energy states at AlGaN/InGaN junction compare to single AlGaN/GaN heterostructure and eliminates the trapping effects. Analysis yielded interface trap energy state in AlGaN/GaN ismore » to be with time constant of (33.8–76.5) μs and trap density of (2.38–0.656) × 10{sup 12 }eV{sup −1} cm{sup −2} in −3.2 to −4.8 V bias region, whereas for AlGaN/InGaN/GaN structure no interface energy states are found and the extracted surface trap energy concentrations and time constants are (5.87–4.39) ×10{sup 10} eV{sup −1} cm{sup −2} and (17.8–11.3) μs, respectively, in bias range of −0.8–0.0 V.« less

  2. Evaluation and comparison of Ga-68 DOTA-TATE and Ga-68 DOTA-NOC PET/CT imaging in well-differentiated thyroid cancer.

    PubMed

    Ocak, Meltem; Demirci, Emre; Kabasakal, Levent; Aygun, Aslan; Tutar, Rumeysa O; Araman, Ahmet; Kanmaz, Bedii

    2013-11-01

    Somatostatin receptor (Sstr) scintigraphy with radiolabelled somatostatin analogues has been used extensively for the diagnosis and therapy of Sstr-expressing tumours. It has been shown that well-differentiated thyroid cancer (WDTC) cells have a high expression of Sstr2, Sstr3 and Sstr5. Hence, WDTC cells could be an ideal target for the evaluation of lesion uptake of Ga-68 DOTA-1-NaI3-octreotide (DOTA-NOC), which has a high affinity not only to Sstr2 but also to Sstr3 and Sstr5. The aim of the present study was to evaluate the value of Ga-68 DOTA-NOC as a target for Sstr2-expressing, Sstr3-expressing and Sstr5-expressing tumours in WDTC patients and to compare the results with those of Ga-68 DOTA-TATE in the same patient population. Thirteen patients with WDTC were included in our study: nine with papillary thyroid cancer, three with Hurthle cell carcinoma and one with follicular thyroid carcinoma. All patients had elevated serum thyroglobulin levels and negative post-therapeutic I-131 whole-body scans, which were obtained after the last radioiodine treatment. All patients had undergone two consecutive PET imaging studies with Ga-68 DOTA-D-Phe1-Tyr3-octreotate (DOTA-TATE) and Ga-68 DOTA-NOC, respectively. All images were evaluated visually, and maximum standardized uptake values were calculated. Both Ga-68 DOTA-TATE and Ga-68 DOTA-NOC PET images gave comparable results. Among the 13 patients, imaging with both Ga-68 DOTA-TATE and Ga-68 DOTA-NOC gave negative results in five (38%) patients and positive results in eight (62%) patients. A total of 45 lesions were identified on Ga-68 DOTA-TATE images and 42 on Ga-68 DOTA-NOC images; three lesions were missed. Lesion uptake was significantly higher on Ga-68 DOTA-TATE images. Maximum standardized uptake values of Ga-68 DOTA-TATE and Ga-68 DOTA-NOC were 12.9±9.1 and 6.3±4.1 (n=54, P<0.001), respectively. Our study suggested that Ga-68 DOTA-TATE has a higher lesion uptake even in WDTC patients and may have potential

  3. Effect of Thermochemical Synthetic Conditions on the Structure and Dielectric Properties of Ga1.9Fe0.1O3 Compounds.

    PubMed

    Roy, Swadipta; Ramana, C V

    2018-02-05

    We report on the tunable and controlled dielectric properties of iron (Fe)-doped gallium oxide (Ga 2 O 3 ; Ga 1.9 Fe 0.1 O 3 , referred to as GFO) inorganic compounds. The GFO materials were synthesized using a standard high-temperature, solid-state chemical reaction method by varying the thermochemical processing conditions, namely, different calcination and sintering environments. Structural characterization by X-ray diffraction revealed that GFO compounds crystallize in the β-Ga 2 O 3 phase. The Fe doping has induced slight lattice strain in GFO, which is evident in structural analysis. The effect of the sintering temperature (T sint ), which was varied in the range of 900-1200 °C, is significant, as revealed by electron microscopy analysis. T sint influences the grain size and microstructure evolution, which, in turn, influences the dielectric and electrical properties of GFO compounds. The energy-dispersive X-ray spectrometry and mapping data demonstrate the uniform distribution of the elemental composition over the microstructure. The temperature- and frequency-dependent dielectric measurements indicate the characteristic features that are specifically due to Fe doping in Ga 2 O 3 . The spreading factor and relaxation time, calculated using Cole-Cole plots, are in the ranges of 0.65-0.76 and 10 -4 s, respectively. The results demonstrate that densification and control over the microstructure and properties of GFO can be achieved by optimizing T sint .

  4. Endohedral gallide cluster superconductors and superconductivity in ReGa5

    PubMed Central

    Xie, Weiwei; Luo, Huixia; Phelan, Brendan F.; Klimczuk, Tomasz; Cevallos, Francois Alexandre; Cava, Robert Joseph

    2015-01-01

    We present transition metal-embedded (T@Gan) endohedral Ga-clusters as a favorable structural motif for superconductivity and develop empirical, molecule-based, electron counting rules that govern the hierarchical architectures that the clusters assume in binary phases. Among the binary T@Gan endohedral cluster systems, Mo8Ga41, Mo6Ga31, Rh2Ga9, and Ir2Ga9 are all previously known superconductors. The well-known exotic superconductor PuCoGa5 and related phases are also members of this endohedral gallide cluster family. We show that electron-deficient compounds like Mo8Ga41 prefer architectures with vertex-sharing gallium clusters, whereas electron-rich compounds, like PdGa5, prefer edge-sharing cluster architectures. The superconducting transition temperatures are highest for the electron-poor, corner-sharing architectures. Based on this analysis, the previously unknown endohedral cluster compound ReGa5 is postulated to exist at an intermediate electron count and a mix of corner sharing and edge sharing cluster architectures. The empirical prediction is shown to be correct and leads to the discovery of superconductivity in ReGa5. The Fermi levels for endohedral gallide cluster compounds are located in deep pseudogaps in the electronic densities of states, an important factor in determining their chemical stability, while at the same time limiting their superconducting transition temperatures. PMID:26644566

  5. Endohedral gallide cluster superconductors and superconductivity in ReGa5.

    PubMed

    Xie, Weiwei; Luo, Huixia; Phelan, Brendan F; Klimczuk, Tomasz; Cevallos, Francois Alexandre; Cava, Robert Joseph

    2015-12-22

    We present transition metal-embedded (T@Gan) endohedral Ga-clusters as a favorable structural motif for superconductivity and develop empirical, molecule-based, electron counting rules that govern the hierarchical architectures that the clusters assume in binary phases. Among the binary T@Gan endohedral cluster systems, Mo8Ga41, Mo6Ga31, Rh2Ga9, and Ir2Ga9 are all previously known superconductors. The well-known exotic superconductor PuCoGa5 and related phases are also members of this endohedral gallide cluster family. We show that electron-deficient compounds like Mo8Ga41 prefer architectures with vertex-sharing gallium clusters, whereas electron-rich compounds, like PdGa5, prefer edge-sharing cluster architectures. The superconducting transition temperatures are highest for the electron-poor, corner-sharing architectures. Based on this analysis, the previously unknown endohedral cluster compound ReGa5 is postulated to exist at an intermediate electron count and a mix of corner sharing and edge sharing cluster architectures. The empirical prediction is shown to be correct and leads to the discovery of superconductivity in ReGa5. The Fermi levels for endohedral gallide cluster compounds are located in deep pseudogaps in the electronic densities of states, an important factor in determining their chemical stability, while at the same time limiting their superconducting transition temperatures.

  6. Twins in spirit - episode I: comparative preclinical evaluation of [(68)Ga]DOTATATE and [(68)Ga]HA-DOTATATE.

    PubMed

    Schottelius, Margret; Šimeček, Jakub; Hoffmann, Frauke; Willibald, Marina; Schwaiger, Markus; Wester, Hans-Jürgen

    2015-01-01

    -mediated accumulation of [(68)Ga]HA-DOTATATE in the pancreas, adrenals, and tumor was significantly enhanced (36.6 ± 4.3, 10.8 ± 3.2, and 33.6 ± 10.9 %iD/g vs 26.1 ± 5.0, 5.1 ± 1.4, and 24.1 ± 4.9 %iD/g, respectively). Consequently, tumor/background ratios for [(68)Ga]HA-DOTATATE in the AR42J model are comparable or slightly increased compared to [(68)Ga]DOTATATE. The present preclinical data fully confirm the general biodistribution pattern and excellent in vivo sst-targeting characteristics previously observed for [(68)Ga]HA-DOTATATE in patients. The effect of slightly enhanced lipophilicity on background accumulation and normal organ dose is compensated by the high uptake of [(68)Ga]HA-DOTATATE in tumor. Thus, [(68)Ga]HA-DOTATATE represents a fully adequate, freely available substitute for [(68)Ga]DOTATATE and, given the superb sst-targeting characteristics of [(177)Lu]HA-DOTATATE in vitro, potential applicability for sst-targeted PRRT.

  7. 68Ga-PSMA PET/MR-Positive, Histopathology-Proven Prostate Cancer in a Patient With Negative Multiparametric Prostate MRI.

    PubMed

    Muehlematter, Urs J; Rupp, Niels J; Mueller, Julian; Eberli, Daniel; Burger, Irene A

    2018-05-25

    Multiparametric MRI incorporating T2-weighted, diffusion-weighted, and dynamic contrast material-enhanced sequences is currently used for detection and localization of clinically important prostate cancer (PCa). The Ga-labeled PET tracer targeting the prostate-specific membrane antigen (PSMA, Ga-PSMA-11) is a promising diagnostic approach for staging and restating PCa. Recent studies suggest that Ga-PSMA could also be used for primary PCa detection and localization. We report a case of a Ga-PSMA PET/MR-positive lesion of the peripheral zone in a 73-year-old man with a negative preceding multiparametric MRI. Radical prostatectomy and subsequent histopathologic examination confirmed a Gleason 4 + 4 PCa.

  8. Legal briefing: informed consent in the clinical context.

    PubMed

    Pope, Thaddeus Mason; Hexum, Melinda

    2014-01-01

    This issue's "Legal Briefing" column covers recent legal developments involving informed consent.1 We covered this topic in previous articles in The Journal of Clinical Ethics.2 But an updated discussion is warranted. First, informed consent remains a central and critically important issue in clinical ethics. Second, there have been numerous significant legal changes over the past year. We categorize recent legal developments into the following 13 categories: (1) Medical Malpractice Liability, (2) Medical Malpractice Liability in Wisconsin, (3) Medical Malpractice Liability in Novel Situations, (4) Enforcement by Criminal Prosecutors, (5) Enforcement by State Medical Boards, (6) Enforcement through Anti-Discrimination Laws, (7) Statutorily Mandated Disclosures Related to End-of-Life Counseling, (8) Statutorily Mandated Disclosures Related to Aid in Dying, (9) Statutorily Mandated Disclosures Related to Abortion, (10) Statutorily Mandated Disclosures Related to Telemedicine, (11) Statutorily Mandated Disclosures Related to Other Interventions, (12) Statutorily Mandated Gag and Censorship Laws, (13) Informed Consent in the Research Context. Copyright 2014 The Journal of Clinical Ethics. All rights reserved.

  9. GaSb/AlGaSb VCSEL structures and microcavities in the 1.5 μm wavelength range

    NASA Astrophysics Data System (ADS)

    Koeth, J.; Dietrich, R.; Reithmaier, J. P.; Forchel, A.

    Vertical cavity surface emitting laser structures for 1.5 μm wavelength applications were realized by growing AlSb/AlGaSb Bragg mirrors on GaAs substrates with solid source molecular beam epitaxy. Due to the high refractive index contrast between GaSb and AlSb high quality resonators can be made by only 15 layer pairs for each Bragg mirror. Laser operation could be demonstrated by optical pumping with threshold excitation densities of about 500 W/cm2. In laterally deeply etched microcavities with diameters of 5 μm a clear discretization of the optical modes was observed. The lateral confinement effects are compared with results of AlAs/GaAs microcavities designed for 0.9 μm emission wavelength. Due to the longer wavelength a stronger confinement effect can be achieved in AlSb/AlGaSb microcavities for the same lateral dimensions.

  10. Electrochemical Reduction Properties of Extended Space Charge InGaP and GaP Epitaxial Layers

    DOE PAGES

    Parameshwaran, Vijay; Xu, Xiaoqing; Clemens, Bruce

    2016-06-17

    Two lattice-matched epitaxial III-V phosphide films of thicknesses between 400 and 500 nm are grown by metal-organic chemical vapor deposition: InGaP on GaAs and GaP on Si. These structures are designed as photocathodes for solar-driven chemical reduction processes such as the hydrogen evolution reaction (HER) and CO 2 reduction into higher-order hydrocarbons. By using p + substrates and undoped epitaxial layers, an extended space-charge active region is achieved in the electrode with a design analogous to a p-i-n solar cell. When in contact with the methyl viologen MV + / + + redox couple, the InGaP/GaAs and GaP/Si cathodes generatemore » a photovoltage of 388 mV and 274 mV, respectively, under 1 sun illumination. Incident photon-to-current efficiency (IPCE) measurements confirm that the undoped active layers are exclusively performing light absorption and minority carrier diffusion-based charge transfer of high-energy photons. This shows that performance can be significantly boosted with lower-doped substrates. The InGaP/GaAs and GaP/Si electrodes are shown to drive the HER at saturation photocurrent densities of 9.05 mA/cm 2 and 2.34 mA/cm 2, respectively, under 1 sun illumination without a co-catalyst and under a large reduction bias. As a result, thicker films did not show a corresponding increased performance, and can be explained through understanding of crystalline defects and the electrostatics of the junctions.« less

  11. Thermoelectric properties of In-rich InGaN and InN/InGaN superlattices

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

    Ju, James; Haunschild, Georg; Loitsch, Bernhard

    2016-04-15

    The thermoelectric properties of n-type InGaN alloys with high In-content and InN/InGaN thin film superlattices (SL) grown by molecular beam epitaxy are investigated. Room-temperature measurements of the thermoelectric properties reveal that an increasing Ga-content in ternary InGaN alloys (0 < x(Ga) < 0.2) yields a more than 10-fold reduction in thermal conductivity (κ) without deteriorating electrical conductivity (σ), while the Seebeck coefficient (S) increases slightly due to a widening band gap compared to binary InN. Employing InN/InGaN SLs (x(Ga) = 0.1) with different periods, we demonstrate that confinement effects strongly enhance electron mobility with values as high as ∼820 cm{supmore » 2}/V s at an electron density n{sub e} of ∼5×10{sup 19} cm{sup −3}, leading to an exceptionally high σ of ∼5400 (Ωcm){sup −1}. Simultaneously, in very short-period SL structures S becomes decoupled from n{sub e}, κ is further reduced below the alloy limit (κ < 9 W/m-K), and the power factor increases to 2.5×10{sup −4} W/m-K{sup 2} by more than a factor of 5 as compared to In-rich InGaN alloys. These findings demonstrate that quantum confinement in group-III nitride-based superlattices facilitates improvements of thermoelectric properties over bulk-like ternary nitride alloys.« less

  12. A phase width for CaGaSn. Crystal structure of mixed intermetallic Ca{sub 4}Ga{sub 4+x}Sn{sub 4−x} and SmGa{sub x}Sn{sub 3−x}, stability, geometry and electronic structure

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

    Tillard, Monique, E-mail: mtillard@univ-montp2.fr

    X-ray single-crystal structure has been established for new compositions in intermetallic systems of tin and gallium. Crystals were successfully obtained in alloys prepared from elements. The structure of SmGaSn{sub 2} (cubic Pm3̄m, a=4.5778(8) Å, Z=1, R1=0.012) is described with atomic disorder at all Sn/Ga positions and the structure of Ca{sub 4}Ga{sub 4.9}Sn{sub 3.1} (hexagonal, P6{sub 3}/mmc, a=4.2233(9), c=17.601(7) Å, Z=1, R1=0.062) raises an interesting question about existence of a composition domain for CaGaSn. Finally, Ca{sub 4}Ga{sub 4.9}Sn{sub 3.1} should be considered as a particular composition of Ca{sub 4}Ga{sub 4+x}Sn{sub 4−x}, a compound assumed to exist in the range x ~more » 0−1. Partial atomic ordering characterizes the Sn/Ga puckered layers of hexagons whose geometries are analyzed and discussed comparatively with analogous arrangements in AlB{sub 2} related hexagonal compounds. The study is supported by rigid band model and DFT calculations performed for different experimental and hypothetic arrangements. - Graphical abstract: A phase width for Ca{sub 4}Ga{sub 4+x}Sn{sub 4−x} belonging to the hexagonal YPtAs structure-type. - Highlights: • Single crystals of mixed tin gallium ternary intermetallics were obtained. • Partial ordering at metal sites and phase width are evidenced for Ca{sub 4}Ga{sub 4+x}Sn{sub 4−x}. • Layer deviation to flatness is studied comparatively with related structures. • Geometry and stability analyses based on DFT calculations are provided.« less

  13. Legally high? Legal considerations of Salvia divinorum.

    PubMed

    Griffin, O Hayden; Miller, Bryan Lee; Khey, David N

    2008-06-01

    The legal status of the hallucinogenic plant Salvia divinorum has been rapidly changing. Legal prohibitions on this plant native to Oaxaca, Mexico have emerged at the state level, a phenomenon that has not occurred since the passage of the Controlled Substances Act (CSA). Included will be a brief description of the plant that has only recently crept into the popular American consciousness, and a review of the different legal mechanisms through which states have controlled the plant and the pending legislation proposing controls. Lastly, the implications of various state laws are discussed.

  14. Ab initio study of Ga-GaN system: Transition from adsorbed metal atoms to a metal–semiconductor junction

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

    Witczak, Przemysław; Kempisty, Pawel; Strak, Pawel

    2015-11-15

    Ab initio studies of a GaN(0001)-Ga system with various thicknesses of a metallic Ga layer were undertaken. The studied systems extend from a GaN(0001) surface with a fractional coverage of gallium atoms to a Ga-GaN metal–semiconductor (m–s) contact. Electronic properties of the system are simulated using density functional theory calculations for different doping of the bulk semiconductor. It is shown that during transition from a bare GaN(0001) surface to a m–s heterostructure, the Fermi level stays pinned at a Ga-broken bond highly dispersive surface state to Ga–Ga states at the m–s interface. Adsorption of gallium leads to an energy gainmore » of about 4 eV for a clean GaN(0001) surface and the energy decreases to 3.2 eV for a thickly Ga-covered surface. The transition to the m–s interface is observed. For a thick Ga overlayer such interface corresponds to a Schottky contact with a barrier equal to 0.9 and 0.6 eV for n- and p-type, respectively. Bond polarization-related dipole layer occurring due to an electron transfer to the metal leads to a potential energy jump of 1.5 eV, independent on the semiconductor doping. Additionally high electron density in the Ga–Ga bond region leads to an energy barrier about 1.2 eV high and 4 Å wide. This feature may adversely affect the conductivity of the n-type m–s system.« less

  15. Enhanced mobility in vertically scaled N-polar high-electron-mobility transistors using GaN/InGaN composite channels

    NASA Astrophysics Data System (ADS)

    Li, Haoran; Wienecke, Steven; Romanczyk, Brian; Ahmadi, Elaheh; Guidry, Matthew; Zheng, Xun; Keller, Stacia; Mishra, Umesh K.

    2018-02-01

    A GaN/InGaN composite channel design for vertically scaled N-polar high-electron-mobility transistor (HEMT) structures is proposed and demonstrated by metal-organic chemical vapor deposition. In a conventional N-polar HEMT structure, as the channel thickness (tch) decreases, the sheet charge density (ns) decreases, the electric field in the channel increases, and the centroid of the two-dimensional electron gas (2DEG) moves towards the back-barrier/channel interface, resulting in stronger scattering and lower electron mobility (μ). In this study, a thin InGaN layer was introduced in-between the channel and the AlGaN cap to increase the 2DEG density and reduce the electric field in the channel and therefore increase the electron mobility. The dependence of μ on the InGaN thickness (tInGaN) and the indium composition (xIn) was investigated for different channel thicknesses. With optimized tInGaN and xIn, significant improvements in electron mobility were observed. For a 6 nm channel HEMT structure, the electron mobility increased from 606 to 1141 cm2/(V.s) when the 6 nm thick pure GaN channel was replaced by the 4 nm GaN/2 nm In0.1Ga0.9N composite channel.

  16. GaIn(N)As/GaAs VCSELs emitting in the 1.1-1.3 μm range

    NASA Astrophysics Data System (ADS)

    Grenouillet, L.; Duvaut, P.; Olivier, N.; Gilet, P.; Grosse, P.; Poncet, S.; Philippe, P.; Pougeoise, E.; Fulbert, L.; Chelnokov, A.

    2006-07-01

    In the field of datacom, 10 Gbit/s sources with a good coupling in monomode silica fibers, whose dispersion minimum occurs at 1.3 μm, are required. Vertical Cavity Surface Emitting Lasers (VCSELs) emitting at 1.3 μm are key components in this field thanks to their compactness, their ability of being operated at high frequencies, their low threshold current and their low beam divergence. Such devices emitting in this wavelength range have been demonstrated using different materials such as strained GaInAs/GaAs quantum wells [1-3], GaInNAs/GaAs quantum wells [4-7], InAs/GaAs quantum dots [8, 9], and antimonides [10], using either molecular beam epitaxy (MBE) or metalorganic vapor phase epitaxy (MOVPE). In the emerging field of photonics on CMOS, there is a need to bond efficient III-V laser sources on SOI wafers. These components should operate at small voltage and current, have a small footprint, and be efficiently couple to Si waveguides, these latter being transparent above 1.1 μm. Since these requirements resemble VCSEL properties, the development of VCSEL emitting above 1.1 μm could therefore benefit to future new sources for photonics on silicon applications. In this context we developed GaAs-based VCSELs emitting in the 1.1 μm - 1.3 μm range with GaInAs/GaAs or GaInNAs/GaAs quantum wells (QWs) as the active materials.

  17. Characteristics of illegal and legal cigarette packs sold in Guatemala.

    PubMed

    Arevalo, Rodrigo; Corral, Juan E; Monzon, Diego; Yoon, Mira; Barnoya, Joaquin

    2016-11-25

    Guatemala, as a party to the Framework Convention on Tobacco Control (FCTC), is required to regulate cigarette packaging and labeling and eliminate illicit tobacco trade. Current packaging and labeling characteristics (of legal and illegal cigarettes) and their compliance with the FCTC is unknown. We sought to analyze package and label characteristics of illegal and legal cigarettes sold in Guatemala. We visited the 22 largest traditional markets in the country to purchase illegal cigarettes. All brands registered on tobacco industry websites were purchased as legal cigarettes. Analysis compared labeling characteristics of illegal and legal packs. Most (95%) markets and street vendors sold illegal cigarettes; 104 packs were purchased (79 illegal and 25 legal). Ten percent of illegal and none of the legal packs had misleading terms. Half of the illegal packs had a warning label covering 26 to 50% of the pack surface. All legal packs had a label covering 25% of the surface. Illegal packs were more likely to have information on constituents and emissions (85% vs. 45%, p < 0.001) and were less expensive than legal ones (USD 0.70 ± 0.7 and 1.9 ± 1.8, p < 0.001). In Guatemala, neither illegal nor legal cigarette packs comply with FCTC labeling mandates. Urgent implementation and enforcement of the FCTC is necessary to halt the tobacco epidemic.

  18. The Growth of Expitaxial GaAs and GaAlAs on Silicon Substrates by OMVPE

    DTIC Science & Technology

    1988-08-01

    structures have been grown on semi-insulating gallium arsenide substrates, and on high-resistivity silicon substrates using a two stage growth technique...fully in Quarter 9. 2. MATERIALS GROWTH 2.1 DOPING OF GALLIUM ARSENIDE FOR FETs As reported in quarter 7, doping levels for GaAs/SI 4ere found to be a...FET structures on both GaAs and Si substrates. A number of FET layers have been grown to the GAT4 specification on semi-insulating gallium arsenide

  19. InGaN light-emitting diodes with highly transparent ZnO:Ga electrodes

    NASA Astrophysics Data System (ADS)

    Liu, H. Y.; Li, X.; Ni, X.; Avrutin, V.; Izyumskaya, N.; Özgür, Ü.; Morkoç, H.

    2010-03-01

    InGaN light-emitting diodes (LEDs) utilizing ZnO layers heavily doped with Ga (GZO) as transparent p-electrodes were fabricated and their characteristics were demonstrated to be superior to those of LEDs with metal Ni/Au electrodes. Highly conductive and highly transparent GZO films were grown on p-GaN contact layers of the LED structures by plasma-assisted molecular beam epitaxy under metal-rich conditions. The c and a lattice constants of GZO were found to be close to the bulk values, indicating small lattice distortion of GZO. The as-grown GZO films showed resistivities as low as 2.2-2.9×10-4 Ω cm. Upon rapid thermal annealing at the optimum temperature of 675 °C, the resistivity decreased reaching a value of ~1.9×10-4 Ω cm. Unlike the LEDs with Ni/Au contacts, the LEDs with GZO electrodes showed no filamentation and very uniform light emission at high current densities. The peak value of the relative external quantum efficiency for the LEDs with GZO contacts has substantial improvement compared with that for the LEDs with Ni/Au contacts. Under pulsed excitation mode, GZO-LEDs withstood current densities up to 5000 A/cm2.

  20. Spatially resolved In and As distributions in InGaAs/GaP and InGaAs/GaAs quantum dot systems.

    PubMed

    Shen, J; Song, Y; Lee, M L; Cha, J J

    2014-11-21

    InGaAs quantum dots (QDs) on GaP are promising for monolithic integration of optoelectronics with Si technology. To understand and improve the optical properties of InGaAs/GaP QD systems, detailed measurements of the QD atomic structure as well as the spatial distributions of each element at high resolution are crucial. This is because the QD band structure, band alignment, and optical properties are determined by the atomic structure and elemental composition. Here, we directly measure the inhomogeneous distributions of In and As in InGaAs QDs grown on GaAs and GaP substrates at the nanoscale using energy dispersive x-ray spectral mapping in a scanning transmission electron microscope. We find that the In distribution is broader on GaP than on GaAs, and as a result, the QDs appear to be In-poor using a GaP matrix. Our findings challenge some of the assumptions made for the concentrations and distributions of In within InGaAs/GaAs or InGaAs/GaP QD systems and provide detailed structural and elemental information to modify the current band structure understanding. In particular, the findings of In deficiency and inhomogeneous distribution in InGaAs/GaP QD systems help to explain photoluminescence spectral differences between InGaAs/GaAs and InGaAs/GaP QD systems.

  1. Physical activity during pregnancy and infant's birth weight: results from the 3D Birth Cohort.

    PubMed

    Bisson, Michèle; Croteau, Jordie; Guinhouya, Benjamin C; Bujold, Emmanuel; Audibert, François; Fraser, William D; Marc, Isabelle

    2017-01-01

    To evaluate the association between maternal physical activity and infant's birth weight or risk of inappropriate weight for gestational age (GA), and whether this association differs by infant's sex, maternal body mass index (BMI) or pregnancy complications in a prospective cohort study. 1913 pregnant women from the 3D Birth Cohort (Québec, Canada) completed the Pregnancy Physical Activity Questionnaire at each trimester. Energy expenditure (metabolic equivalent of task (MET)*hours/week) for total activity, sports and exercise and vigorous intensity activities was calculated. The associations with birth weight and risk of inappropriate weight for GA were evaluated by regression modelling. Interactions were tested with infant's sex, maternal prepregnancy BMI, gestational diabetes, hypertensive disorders and prematurity. Each 1 MET/hours/week increase in sports and exercise in the first trimester was associated with a 2.5 g reduction in infant's birth weight (95% CI -4.8 to -0.3) but was not associated with the risk of small weight for GA. In contrast, although not significant, a 17% reduction in the risk of large weight for GA was observed with increasing sports and exercise. Furthermore, in women with subsequent pre-eclampsia (but not normotensive or hypertensive women), each 1 MET/hours/week increment spent in any vigorous exercise in the first trimester reduced the infant's birth weight by 19.8 g (95% CI -35.2 to -4.3). Pregnant women with higher sports and exercise levels in the first trimester delivered infants with a lower birth weight. The risk of reducing infant's birth weight with vigorous exercise in women who develop pre-eclampsia later in pregnancy requires evaluation.

  2. Interpenetration of a 3D Icosahedral M@Ni12 (M=Al, Ga) Framework with Porphyrin-Reminiscent Boron Layers in MNi9 B8.

    PubMed

    Zheng, Qiang; Wagner, Frank R; Ormeci, Alim; Prots, Yurii; Burkhardt, Ulrich; Schmidt, Marcus; Schnelle, Walter; Grin, Yuri; Leithe-Jasper, Andreas

    2015-11-09

    Two ternary borides MNi9 B8 (M=Al, Ga) were synthesized by thermal treatment of mixtures of the elements. Single-crystal X-ray diffraction data reveal AlNi9 B8 and GaNi9 B8 crystallizing in a new type of structure within the space group Cmcm and the lattice parameters a=7.0896(3) Å, b=8.1181(3) Å, c=10.6497(4) Å and a=7.0897(5) Å, b=8.1579(4) Å, c=10.6648(7) Å, respectively. The boron atoms build up two-dimensional layers, which consist of puckered [B16 ] rings with two tailing B atoms, whereas the M atoms reside in distorted vertices-condensed [Ni12 ] icosahedra, which form a three-dimensional framework interpenetrated by boron porphyrin-reminiscent layers. An unusual local arrangement resembling a giant metallo-porphyrin entity is formed by the [B16 ] rings, which, due to their large annular size of approximately 8 Å, chelate four of the twelve icosahedral Ni atoms. An analysis of the chemical bonding by means of the electron localizability approach reveals strong covalent B-B interactions and weak Ni-Ni interactions. Multi-center dative B-Ni interaction occurs between the Al-Ni framework and the boron layers. In agreement with the chemical bonding analysis and band structure calculations, AlNi9 B8 is a Pauli-paramagnetic metal. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Type II GaSb quantum ring solar cells under concentrated sunlight.

    PubMed

    Tsai, Che-Pin; Hsu, Shun-Chieh; Lin, Shih-Yen; Chang, Ching-Wen; Tu, Li-Wei; Chen, Kun-Cheng; Lay, Tsong-Sheng; Lin, Chien-chung

    2014-03-10

    A type II GaSb quantum ring solar cell is fabricated and measured under the concentrated sunlight. The external quantum efficiency confirms the extended absorption from the quantum rings at long wavelength coinciding with the photoluminescence results. The short-circuit current of the quantum ring devices is 5.1% to 9.9% more than the GaAs reference's under various concentrations. While the quantum ring solar cell does not exceed its GaAs counterpart in efficiency under one-sun, the recovery of the open-circuit voltages at higher concentration helps to reverse the situation. A slightly higher efficiency (10.31% vs. 10.29%) is reported for the quantum ring device against the GaAs one.

  4. Highly resistive C-doped hydride vapor phase epitaxy-GaN grown on ammonothermally crystallized GaN seeds

    NASA Astrophysics Data System (ADS)

    Iwinska, Malgorzata; Piotrzkowski, Ryszard; Litwin-Staszewska, Elzbieta; Sochacki, Tomasz; Amilusik, Mikolaj; Fijalkowski, Michal; Lucznik, Boleslaw; Bockowski, Michal

    2017-01-01

    GaN crystals were grown by hydride vapor phase epitaxy (HVPE) and doped with C. The seeds were high-structural-quality ammonothermally crystallized GaN. The grown crystals were highly resistive at 296 K and of high structural quality. High-temperature Hall effect measurements revealed p-type conductivity and a deep acceptor level in the material with an activation energy of 1 eV. This is in good agreement with density functional theory calculations based on hybrid functionals as presented by the Van de Walle group. They obtained an ionization energy of 0.9 eV when C was substituted for N in GaN and acted as a deep acceptor.

  5. Degradation mechanisms of 2 MeV proton irradiated AlGaN/GaN HEMTs

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

    Greenlee, Jordan D., E-mail: jordan.greenlee.ctr@nrl.navy.mil; Anderson, Travis J.; Koehler, Andrew D.

    2015-08-24

    Proton-induced damage in AlGaN/GaN HEMTs was investigated using energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM), and simulated using a Monte Carlo technique. The results were correlated to electrical degradation using Hall measurements. It was determined by EDS that the interface between GaN and AlGaN in the irradiated HEMT was broadened by 2.2 nm, as estimated by the width of the Al EDS signal compared to the as-grown interface. The simulation results show a similar Al broadening effect. The extent of interfacial roughening was examined using high resolution TEM. At a 2 MeV proton fluence of 6 × 10{sup 14} H{supmore » +}/cm{sup 2}, the electrical effects associated with the Al broadening and surface roughening include a degradation of the ON-resistance and a decrease in the electron mobility and 2DEG sheet carrier density by 28.9% and 12.1%, respectively.« less

  6. Comparison of a reduced carbohydrate and reduced fat diet for LDL, HDL, and VLDL subclasses during 9-months of weight maintenance subsequent to weight loss.

    PubMed

    LeCheminant, James D; Smith, Bryan K; Westman, Eric C; Vernon, Mary C; Donnelly, Joseph E

    2010-06-01

    This study compared LDL, HDL, and VLDL subclasses in overweight or obese adults consuming either a reduced carbohydrate (RC) or reduced fat (RF) weight maintenance diet for 9 months following significant weight loss. Thirty-five (21 RC; 14 RF) overweight or obese middle-aged adults completed a 1-year weight management clinic. Participants met weekly for the first six months and bi-weekly thereafter. Meetings included instruction for diet, physical activity, and behavior change related to weight management. Additionally, participants followed a liquid very low-energy diet of approximately 2092 kJ per day for the first three months of the study. Subsequently, participants followed a dietary plan for nine months that targeted a reduced percentage of carbohydrate (approximately 20%) or fat (approximately 30%) intake and an energy intake level calculated to maintain weight loss. Lipid subclasses using NMR spectroscopy were analyzed prior to weight loss and at multiple intervals during weight maintenance. Body weight change was not significantly different within or between groups during weight maintenance (p>0.05). The RC group showed significant increases in mean LDL size, large LDL, total HDL, large and small HDL, mean VLDL size, and large VLDL during weight maintenance while the RF group showed increases in total HDL, large and small HDL, total VLDL, and large, medium, and small VLDL (p<0.05). Group*time interactions were significant for large and medium VLDL (p>0.05). Some individual lipid subclasses improved in both dietary groups. Large and medium VLDL subclasses increased to a greater extent across weight maintenance in the RF group.

  7. Naphyrone: a "legal high" not legal any more.

    PubMed

    Vardakou, Ioanna; Pistos, Constantinos; Dona, Artemis; Spiliopoulou, Chara; Athanaselis, Sotiris

    2012-10-01

    Naphyrone, also known as naphthylpyrovalerone and O-2482, is a cathinone derivative that has been recently advertized for purchase on a number of websites. Naphyrone belongs to a new class of "designer drugs" that has emerged on the drugs abuse market and has gained popularity as the new "legal high." Legal highs have been circulating for a number of years in Europe and are becoming popular in the United States. They are affordable, widely available, legal to use and possess, and legal to supply. This review presents any available information about safety profile, clinical data, analytical profile, and legislation of this legal high, which is not legal any more. Any available information has been collected by various literature search engines and the World Wide Web. The structure of naphyrone is similar to that of pyrovalerone, a monoamine uptake inhibitor. This new designer drug does not have a long history of use, so there is little evidence of its long-term effects or on the risks from its use. Because of its similarity to other cathinone derivatives, naphyrone is likely to share the same risks, such as anxiety, paranoia, and overstimulation of the heart and circulatory system. Naphyrone was classified as a controlled drug under the UK Misuse of Drugs Act of 1971 (Amendment No. 2) Regulation 2010.

  8. Legal and regulatory capacity to support the global health security agenda.

    PubMed

    Morhard, Ryan; Katz, Rebecca

    2014-01-01

    On February 13, 2014, 27 nations, along with 3 international organizations, launched the Global Health Security Agenda (GHSA). The intent of GHSA is to accelerate progress in enabling countries around the world to prevent, detect, and respond to public health emergencies-capacities to be achieved through 9 core objectives. Building national, regional, and international capacity includes creating strong legal and regulatory regimes to support national and international capacities to prevent, detect, and respond to public health emergencies. Accordingly, establishing and reinforcing international and national-level legal preparedness is central to advancing elements of each of the 9 objectives of the GHSA.

  9. Kinetic modeling of microscopic processes during electron cyclotron resonance microwave plasma-assisted molecular beam epitaxial growth of GaN/GaAs-based heterostructures

    NASA Astrophysics Data System (ADS)

    Bandić, Z. Z.; Hauenstein, R. J.; O'Steen, M. L.; McGill, T. C.

    1996-03-01

    Microscopic growth processes associated with GaN/GaAs molecular beam epitaxy (MBE) are examined through the introduction of a first-order kinetic model. The model is applied to the electron cyclotron resonance microwave plasma-assisted MBE (ECR-MBE) growth of a set of δ-GaNyAs1-y/GaAs strained-layer superlattices that consist of nitrided GaAs monolayers separated by GaAs spacers, and that exhibit a strong decrease of y with increasing T over the range 540-580 °C. This y(T) dependence is quantitatively explained in terms of microscopic anion exchange, and thermally activated N surface-desorption and surface-segregation processes. N surface segregation is found to be significant during GaAs overgrowth of GaNyAs1-y layers at typical GaN ECR-MBE growth temperatures, with an estimated activation energy Es˜0.9 eV. The observed y(T) dependence is shown to result from a combination of N surface segregation/desorption processes.

  10. Defect-Reduction Mechanism for Improving Radiative Efficiency in InGaN/GaN Light-Emitting Diodes using InGaN Underlayers

    DOE PAGES

    Armstrong, Andrew M.; Bryant, Benjamin N.; Crawford, Mary H.; ...

    2015-04-01

    The influence of a dilute In xGa 1-xN (x~0.03) underlayer (UL) grown below a single In 0.16Ga 0.84N quantum well (SQW), within a light-emitting diode(LED), on the radiative efficiency and deep level defect properties was studied using differential carrier lifetime (DCL) measurements and deep level optical spectroscopy (DLOS). DCL measurements found that inclusion of the UL significantly improved LED radiative efficiency. At low current densities, the non-radiative recombination rate of the LED with an UL was found to be 3.9 times lower than theLED without an UL, while the radiative recombination rates were nearly identical. This, then, suggests that themore » improved radiative efficiency resulted from reduced non-radiative defect concentration within the SQW. DLOS measurement found the same type of defects in the InGaN SQWs with and without ULs. However, lighted capacitance-voltage measurements of the LEDs revealed a 3.4 times reduction in a SQW-related near-mid-gap defect state for the LED with an UL. Furthermore, quantitative agreement in the reduction of both the non-radiative recombination rate (3.9×) and deep level density (3.4×) upon insertion of an UL corroborates deep level defect reduction as the mechanism for improved LED efficiency.« less

  11. Clinical 68Ga-PET: Is radiosynthesis module an absolute necessity?

    PubMed

    Chakravarty, Rubel; Chakraborty, Sudipta; Radhakrishnan, E R; Kamaleshwaran, Koramadai; Shinto, Ajit; Dash, Ashutosh

    2017-03-01

    The commercially available 68 Ge/ 68 Ga generators are generally used in clinical context in conjunction with automated or semi-automated modules for the syntheses of 68 Ga radiopharmaceuticals. It is desirable to develop strategies for the formulation of 68 Ga-radiopharmaceuticals without use of such expensive modules in order to make 68 Ga-based clinical positron emission tomography (PET) more popular and affordable worldwide. An organic matrix based 68 Ge/ 68 Ga generator was used for preparation of clinically relevant doses of four different 68 Ga-based radiopharmaceuticals, namely 68 Ga-DOTA-NOC, 68 Ga-NODAGA-RGD 2 , 68 Ga-PSMA-11 and 68 Ga-BPAMD. Detailed performance evaluation of the generator was carried out over the period of 9months. The radiolabeling conditions were optimized in a hospital radiopharmacy directly utilizing 68 Ga eluted from the generator without use of any synthesis module. Quality control tests of the radiopharmaceuticals were carried out to assess their suitability for clinical use. The clinical utility of the synthesized radiopharmaceuticals was ascertained by performing PET scans in human patients. During the period of evaluation, 68 Ga could be obtained from the generator in 4mL of 0.05M HCl with 60-85% elution yield and >99.99% radionuclidic purity. While directly using 68 Ga eluted from the generator, the 68 Ga-based radiopharmaceuticals could be prepared with >95% radiochemical purity and they met all the requirements for clinical administration. The clinical efficacy of the radiopharmaceuticals synthesized was established by PET scans in human patients. The performance of the generator remained consistent over the 9-month period and >100 clinical doses of different radiopharmaceuticals were prepared with excellent reproducibility and clinical effectiveness. The promising results obtained in this study would make 68 Ga-radiopharmacy more practical and cost effective in clinical context. To the best of our knowledge, this is the

  12. Characteristics of GaAs with inverted thermal conversion

    NASA Technical Reports Server (NTRS)

    Kang, C. H.; Lagowski, J.; Gatos, H. C.

    1987-01-01

    GaAs crystals exhibiting inverted thermal conversion (ITC) of resistivity were investigated in conjunction with standard semiinsulating (SI) GaAs regarding characteristics important in device processing. It was established that dislocation density and Si implant activation are unaffected by transformation to the ITC state. However, in ITC GaAs the controlled increase of the EL2 (native midgap donor) concentration during annealing makes it possible to attain resistivities one order of magnitude greater (e.g., about 10 to the 9th ohm cm of 300 K) than those attained in standard SI GaAs (e.g., 10 to the 7th-10 to the 8th ohm cm).

  13. Phase relationships in the BaO-Ga2O3-Ta2O5 system and the structure of Ba6Ga21TaO40.

    PubMed

    Cao, Jiang; Yu, Xiaodi; Kuang, Xiaojun; Su, Qiang

    2012-07-16

    Phase relationships in the BaO-Ga(2)O(3)-Ta(2)O(5) ternary system at 1200 °C were determined. The A(6)B(10)O(30) tetragonal tungsten bronze (TTB) related solution in the BaO-Ta(2)O(5) subsystem dissolved up to ~11 mol % Ga(2)O(3), forming a ternary trapezoid-shaped TTB-related solid solution region defined by the BaTa(2)O(6), Ba(1.1)Ta(5)O(13.6), Ba(1.58)Ga(0.92)Ta(4.08)O(13.16), and Ba(6)GaTa(9)O(30) compositions in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Two ternary phases Ba(6)Ga(21)TaO(40) and eight-layer twinned hexagonal perovskite solid solution Ba(8)Ga(4-x)Ta(4+0.6x)O(24) were confirmed in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Ba(6)Ga(21)TaO(40) crystallized in a monoclinic cell of a = 15.9130(2) Å, b = 11.7309(1) Å, c = 5.13593(6) Å, β = 107.7893(9)°, and Z = 1 in space group C2/m. The structure of Ba(6)Ga(21)TaO(40) was solved by the charge flipping method, and it represents a three-dimensional (3D) mixed GaO(4) tetrahedral and GaO(6)/TaO(6) octahedral framework, forming mixed 1D 5/6-fold tunnels that accommodate the Ba cations along the c axis. The electrical property of Ba(6)Ga(21)TaO(40) was characterized by using ac impedance spectroscopy.

  14. Rapid Infancy Weight Gain and 7- to 9-year Childhood Obesity Risk: A Prospective Cohort Study in Rural Western China.

    PubMed

    Zhou, Jing; Dang, Shaonong; Zeng, Lingxia; Gao, Wenlong; Wang, Duolao; Li, Qiang; Jiang, Wenhui; Pei, Leilei; Li, Chao; Yan, Hong

    2016-04-01

    Obesity is increasing in developing countries. This study aimed to identify the association between rapid infancy weight gain and obesity risk among early school-age children. A total of 581 singletons (349 boys, 232 girls) whose mothers participated in an antenatal multiple micronutrient supplement trial in rural western China were followed from birth to between 7 and 9 years of age. Height and weight were measured at birth, 1.5 years, and between 7 and 9 years. At the 7- to 9-year time point, body composition was determined using bioelectrical impedance analysis. Multilevel mixed analysis was used to test the associations between rapid weight gain in infancy (from birth to age 1.5 years) and body size and composition or overweight/obesity among early school-age children. Overall, 31.2% (181 of 581) of the infants showed a weight-for-age Z score gain greater than 0.67 between birth and 1.5 years, indicating rapid weight gain. Approximately 5.7% (33 of 579) of the subjects were overweight (BMI-for-age Z scores [BAZ] >1 and ≤2) or obese (BAZ >2). Rapid infancy weight gain was associated with a higher BAZ (P < 0.001), mid-upper arm circumferences (P < 0.001), percentage body fat (P < 0.001), and fat mass index (P < 0.001) at 7 to 9 years of age after adjusting for biological and social economic factors, genetic factors, and perinatal and postnatal factors. These associations appeared to be independent of gender, economic status at early school age, and maternal nutritional status at enrollment. Rapid growers may have approximately 3 times the risk of being overweight/obese during the early school-age years (odds ratio = 2.94, 95% CI: 1.17-7.43, P = 0.022). Rapid infancy weight gain is a risk factor for being overweight/obesity among early school-age children in rural western China. We propose that social and biological determinants, such as economic status, physical activity, and feeding practice, should be targeted to prevent obesity.

  15. GaSb solar cells grown on GaAs via interfacial misfit arrays for use in the III-Sb multi-junction cell

    NASA Astrophysics Data System (ADS)

    Nelson, George T.; Juang, Bor-Chau; Slocum, Michael A.; Bittner, Zachary S.; Laghumavarapu, Ramesh B.; Huffaker, Diana L.; Hubbard, Seth M.

    2017-12-01

    Growth of GaSb with low threading dislocation density directly on GaAs may be possible with the strategic strain relaxation of interfacial misfit arrays. This creates an opportunity for a multi-junction solar cell with access to a wide range of well-developed direct bandgap materials. Multi-junction cells with a single layer of GaSb/GaAs interfacial misfit arrays could achieve higher efficiency than state-of-the-art inverted metamorphic multi-junction cells while forgoing the need for costly compositionally graded buffer layers. To develop this technology, GaSb single junction cells were grown via molecular beam epitaxy on both GaSb and GaAs substrates to compare homoepitaxial and heteroepitaxial GaSb device results. The GaSb-on-GaSb cell had an AM1.5g efficiency of 5.5% and a 44-sun AM1.5d efficiency of 8.9%. The GaSb-on-GaAs cell was 1.0% efficient under AM1.5g and 4.5% at 44 suns. The lower performance of the heteroepitaxial cell was due to low minority carrier Shockley-Read-Hall lifetimes and bulk shunting caused by defects related to the mismatched growth. A physics-based device simulator was used to create an inverted triple-junction GaInP/GaAs/GaSb model. The model predicted that, with current GaSb-on-GaAs material quality, the not-current-matched, proof-of-concept cell would provide 0.5% absolute efficiency gain over a tandem GaInP/GaAs cell at 1 sun and 2.5% gain at 44 suns, indicating that the effectiveness of the GaSb junction was a function of concentration.

  16. Sublattice reversal in GaAs/Ge/GaAs (113)B heterostructures and its application to THz emitting devices based on a coupled multilayer cavity

    NASA Astrophysics Data System (ADS)

    Lu, Xiangmeng; Kumagai, Naoto; Minami, Yasuo; Kitada, Takahiro

    2018-04-01

    We fabricated a coupled multilayer cavity with a GaAs/Ge/GaAs sublattice reversal structure for terahertz emission application. Sublattice reversal in GaAs/Ge/GaAs was confirmed by comparing the anisotropic etching profile of an epitaxial sample with those of reference (113)A and (113)B GaAs substrates. The interfaces of GaAs/Ge/GaAs were evaluated at the atomic level by scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDX) mapping. Defect-free GaAs/Ge/GaAs heterostructures were observed in STEM images and the sublattice lattice was directly seen through atomic arrangements in EDX mapping. A GaAs/AlAs coupled multilayer cavity with a sublattice reversal structure was grown on the (113)B GaAs substrate after the confirmation of sublattice reversal. Smooth GaAs/AlAs interfaces were formed over the entire region of the coupled multilayer cavity structure both below and above the Ge layer. Two cavity modes with a frequency difference of 2.9 THz were clearly observed.

  17. Study of Radiation Hardness of Lattice Matched AlInN/GaN HEMT Heterostructures

    DTIC Science & Technology

    2016-10-01

    Challenges .............................................. 6 2.4. Gamma Ray Irradiation of AlInN/GaN & AlGaN/GaN HEMT Structures...8 2.4.1. Characterization of Irradiated AlInN/GaN and AlGaN/GaN HEMT Heterostructures .................... 8 2.4.2. APT of Baseline Un... Irradiated Lattice Matched AlInN/GaN HEMT Heterostructures ................... 9 2.4.3. APT of Gamma- Irradiated Lattice Matched AlInN/GaN HEMT

  18. Possibility of a quasi-liquid layer of As on GaAs substrate grown by MBE as observed by enhancement of Ga desorption at high As pressure

    NASA Astrophysics Data System (ADS)

    Asai, K.; Feng, J. M.; Vaccaro, P. O.; Fujita, K.; Ohachi, T.

    2000-06-01

    The As vapor pressure dependence of the Ga desorption rate during molecular beam epitaxy (MBE) growth on GaAs( n11)A ( n=1-4 hereafter) substrates was studied by photoluminescence (PL) measurements at 12 K for undoped AlGaAs/GaAs asymmetric double quantum wells (ADQWs). Reflection high energy electron diffraction (RHEED) oscillation measurements on a GaAs(100) surface were also used. Two K-cells of As solid sources (corresponding to beam equivalent pressures (BEPs) of 9.0×10 -6 and 4.5×10 -5 Torr) were used to change the As pressure rapidly. The Ga flux and substrate temperature were kept constant at 0.76 ML/s and 12 K, respectively, while the As flux changed from 7.6 (BEP 9.0×10 -6 Torr) to 32 ML/s (4.5×10 -5 Torr). With increasing As pressure, two separated PL peaks for the wide well (WW) of high index substrates were observed. This peak separation is attributed to a reduced well depth from an increasing Ga desorption rate. The energy differences of the PL peak depending on the off-angle from (111)A to (100) plane indicates an orientation-dependent Ga desorption rate. Moreover, amongst all ( n11)A and (100) planes, the Ga desorption rate was smallest from the (111)A surface. The increase of Ga desorption from the surface at high As pressures probably arose from an increasing coverage with a quasi-liquid layer (QLL).

  19. How Does Legalization of Physician-Assisted Suicide Affect Rates of Suicide?

    PubMed

    Jones, David Albert; Paton, David

    2015-10-01

    Several US states have legalized or decriminalized physician-assisted suicide (PAS) while others are considering permitting PAS. Although it has been suggested that legalization could lead to a reduction in total suicides and to a delay in those suicides that do occur, to date no research has tested whether these effects can be identified in practice. The aim of this study was to fill this gap by examining the association between the legalization of PAS and state-level suicide rates in the United States between 1990 and 2013. We used regression analysis to test the change in rates of nonassisted suicides and total suicides (including assisted suicides) before and after the legalization of PAS. Controlling for various socioeconomic factors, unobservable state and year effects, and state-specific linear trends, we found that legalizing PAS was associated with a 6.3% (95% confidence interval 2.70%-9.9%) increase in total suicides (including assisted suicides). This effect was larger in the individuals older than 65 years (14.5%, CI 6.4%-22.7%). Introduction of PAS was neither associated with a reduction in nonassisted suicide rates nor with an increase in the mean age of nonassisted suicide. Legalizing PAS has been associated with an increased rate of total suicides relative to other states and no decrease in nonassisted suicides. This suggests either that PAS does not inhibit (nor acts as an alternative to) nonassisted suicide, or that it acts in this way in some individuals but is associated with an increased inclination to suicide in other individuals.

  20. Assessing the public health impact of cannabis legalization in Canada: core outcome indicators towards an 'index' for monitoring and evaluation.

    PubMed

    Fischer, Benedikt; Russell, Cayley; Rehm, Jürgen; Leece, Pamela

    2018-05-30

    The legalization of non-medical cannabis use and supply is impending in Canada. This constitutes a major policy change with the declared objective of improving public health outcomes, which requires rigorous monitoring and evaluation. While numerous different aspects associated with legalization will be examined, a focused perspective is required for effective policy evaluation purposes. To these ends, we have identified a set of 10 core indicators associated with cannabis-related risk/harm outcomes-based on current best evidence-that are expected to measure the primary impacts of legalization on public health outcomes. We briefly review these indicators, and their respective data availability in Canada. As ideally an integrated outcome assessment of cannabis legalization's impact on public health will be available, we further propose options to merge the individual indicators into an integrated, weighted 'index', considering their expected relative impact for public health. One possible approach to undertake this is 'multi-criteria decision analysis' as a method to weight the relative indicator impact on public health; alternative approaches are proposed. The integrated 'public health index' for cannabis legalization will allow for scientifically comprehensive, while focused, monitoring and evaluation of the effects of legalization in Canada for the benefits of science and evidence-based policy alike.

  1. Defect-related photoluminescence in Mg-doped GaN nanostructures

    NASA Astrophysics Data System (ADS)

    Reshchikov, M. A.; Shahedipour-Sandvik, F.; Messer, B. J.; Jindal, V.; Tripathi, N.; Tungare, M.

    2009-12-01

    Thin film of GaN:Mg, pyramidal GaN:Mg on GaN, sapphire and AlN substrates were grown in a MOCVD system under same growth conditions and at the same time. In samples with Mg-doped GaN pyramids on GaN:Si template a strong ultraviolet (UVL) band with few phonon replicas dominated at low temperature and was attributed to transitions from shallow donors to shallow Mg acceptor. In samples grown on sapphire and AlN substrates the UVL band appeared as a structureless band with the maximum at about 3.25 eV. There is a possibility that the structureless UVL band and the UVL band with phonon structure have different origin. In addition to the UVL band, the blue luminescence (BL) band peaking at 2.9 eV was observed in samples representing GaN:Mg pyramids on GaN:Si substrate. It is preliminary attributed to transitions from shallow donors to Zn acceptor in GaN:Si substrate.

  2. Performance Analysis of GaN Capping Layer Thickness on GaN/AlGaN/GaN High Electron Mobility Transistors.

    PubMed

    Sharma, N; Periasamy, C; Chaturvedi, N

    2018-07-01

    In this paper, we present an investigation of the impact of GaN capping layer and AlGaN layer thickness on the two-dimensional (2D)-electron mobility and the carrier concentration which was formed close to the AlGaN/GaN buffer layer for Al0.25Ga0.75N/GaN and GaN/Al0.25Ga0.75N/GaN heterostructures deposited on sapphire substrates. The results of our analysis clearly indicate that expanding the GaN capping layer thickness from 1 nm to 100 nm prompts an increment in the electron concentration at hetero interface. As consequence of which drain current was additionally increments with GaN cap layer thicknesses, and eventually saturates at approximately 1.85 A/mm for capping layer thickness greater than 40 nm. Interestingly, for the same structure, the 2D-electron mobility, decrease monotonically with GaN capping layer thickness, and saturate at approximately 830 cm2/Vs for capping layer thickness greater than 50 nm. A device with a GaN cap layer didn't exhibit gate leakage current. Furthermore, it was observed that the carrier concentration was first decrease 1.03 × 1019/cm3 to 6.65 × 1018/cm3 with AlGaN Layer thickness from 5 to 10 nm and after that it increases with the AlGaN layer thickness from 10 to 30 nm. The same trend was followed for electric field distributions. Electron mobility decreases monotonically with AlGaN layer thickness. Highest electron mobility 1354 cm2/Vs were recorded for the AlGaN layer thickness of 5 nm. Results obtained are in good agreement with published experimental data.

  3. Improving anti-bullying laws and policies to protect youth from weight-based victimization: parental support for action.

    PubMed

    Puhl, R M; Suh, Y; Li, X

    2017-04-01

    Weight-based bullying is a prevalent problem among youth with overweight and obesity, but remains neglected in existing policy-level strategies to address youth bullying. Parental support is an influential catalyst motivating political will for policy decisions affecting youth, but has received limited research attention. To assess levels of, and predictors of, parental support for school-based policies and state/federal legal measures to address weight-based bullying in 2014 and 2015. Identical online questionnaires were completed by two independent national samples of parents in 2014 and 2015 (N = 1804). Parental support for all policy actions was high (at least 81%) and significantly increased from 2014 to 2015 for legal measures that would a) require state anti-bullying laws to add protections against weight-based bullying, and b) enact a federal anti-bullying law that includes weight-based bullying. These findings can inform policy discourse about remedies for youth bullying, and suggest that parental support for improved legal protections against weight-based bullying is present, consistent, and strong. © 2016 World Obesity Federation.

  4. Open-Gated pH Sensor Fabricated on an Undoped-AlGaN/GaN HEMT Structure

    PubMed Central

    Abidin, Mastura Shafinaz Zainal; Hashim, Abdul Manaf; Sharifabad, Maneea Eizadi; Rahman, Shaharin Fadzli Abd; Sadoh, Taizoh

    2011-01-01

    The sensing responses in aqueous solution of an open-gated pH sensor fabricated on an AlGaN/GaN high-electron-mobility-transistor (HEMT) structure are investigated. Under air-exposed ambient conditions, the open-gated undoped AlGaN/GaN HEMT only shows the presence of a linear current region. This seems to show that very low Fermi level pinning by surface states exists in the undoped AlGaN/GaN sample. In aqueous solution, typical current-voltage (I-V) characteristics with reasonably good gate controllability are observed, showing that the potential of the AlGaN surface at the open-gated area is effectively controlled via aqueous solution by the Ag/AgCl gate electrode. The open-gated undoped AlGaN/GaN HEMT structure is capable of distinguishing pH level in aqueous electrolytes and exhibits linear sensitivity, where high sensitivity of 1.9 mA/pH or 3.88 mA/mm/pH at drain-source voltage, VDS = 5 V is obtained. Due to the large leakage current where it increases with the negative gate voltage, Nernstian like sensitivity cannot be determined as commonly reported in the literature. This large leakage current may be caused by the technical factors rather than any characteristics of the devices. Surprisingly, although there are some imperfections in the device preparation and measurement, the fabricated devices work very well in distinguishing the pH levels. Suppression of current leakage by improving the device preparation is likely needed to improve the device performance. The fabricated device is expected to be suitable for pH sensing applications. PMID:22163786

  5. 32 CFR 776.9 - Rules Counsel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 776.9 Rules Counsel. Appointed by JAG to act as special assistants for the administration of this part... general interest to the DON legal community to be published in summarized, non-personal form in suitable... advocates, or civil service and contracted civilian attorneys who perform legal services under his...

  6. 32 CFR 776.9 - Rules Counsel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... § 776.9 Rules Counsel. Appointed by JAG to act as special assistants for the administration of this part... general interest to the DON legal community to be published in summarized, non-personal form in suitable... advocates, or civil service and contracted civilian attorneys who perform legal services under his...

  7. 32 CFR 776.9 - Rules Counsel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 776.9 Rules Counsel. Appointed by JAG to act as special assistants for the administration of this part... general interest to the DON legal community to be published in summarized, non-personal form in suitable... advocates, or civil service and contracted civilian attorneys who perform legal services under his...

  8. 32 CFR 776.9 - Rules Counsel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... § 776.9 Rules Counsel. Appointed by JAG to act as special assistants for the administration of this part... general interest to the DON legal community to be published in summarized, non-personal form in suitable... advocates, or civil service and contracted civilian attorneys who perform legal services under his...

  9. 32 CFR 776.9 - Rules Counsel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... § 776.9 Rules Counsel. Appointed by JAG to act as special assistants for the administration of this part... general interest to the DON legal community to be published in summarized, non-personal form in suitable... advocates, or civil service and contracted civilian attorneys who perform legal services under his...

  10. Enhanced light extraction from free-standing InGaN/GaN light emitters using bio-inspired backside surface structuring.

    PubMed

    Pynn, Christopher D; Chan, Lesley; Lora Gonzalez, Federico; Berry, Alex; Hwang, David; Wu, Haoyang; Margalith, Tal; Morse, Daniel E; DenBaars, Steven P; Gordon, Michael J

    2017-07-10

    Light extraction from InGaN/GaN-based multiple-quantum-well (MQW) light emitters is enhanced using a simple, scalable, and reproducible method to create hexagonally close-packed conical nano- and micro-scale features on the backside outcoupling surface. Colloidal lithography via Langmuir-Blodgett dip-coating using silica masks (d = 170-2530 nm) and Cl 2 /N 2 -based plasma etching produced features with aspect ratios of 3:1 on devices grown on semipolar GaN substrates. InGaN/GaN MQW structures were optically pumped at 266 nm and light extraction enhancement was quantified using angle-resolved photoluminescence. A 4.8-fold overall enhancement in light extraction (9-fold at normal incidence) relative to a flat outcoupling surface was achieved using a feature pitch of 2530 nm. This performance is on par with current photoelectrochemical (PEC) nitrogen-face roughening methods, which positions the technique as a strong alternative for backside structuring of c-plane devices. Also, because colloidal lithography functions independently of GaN crystal orientation, it is applicable to semipolar and nonpolar GaN devices, for which PEC roughening is ineffective.

  11. Inmetro - Metrologia Legal

    Science.gov Websites

    Ética Mapa do site English Version Inmetro Metrologia Legal Procurando algo? Inmetro no Facebook Metrologia Legal Introdução .: Introdução :. A Metrologia Legal é parte da metrologia relacionada às ambiente. No Brasil as atividades da Metrologia Legal são uma atribuição do Inmetro, que também

  12. Utilization of legal and financial services of partners in dementia care study.

    PubMed

    Shrestha, Srijana; Judge, Katherine S; Wilson, Nancy L; Moye, Jennifer A; Snow, A Lynn; Kunik, Mark E

    2011-03-01

    Financial and legal services are unique needs of persons with dementia and their caregivers. This study examines their need for legal and financial assistance and the kinds of legal and financial services provided within Partners in Dementia Care, a telephone-based, care coordination and support service intervention delivered through a partnership between Veterans Affairs (VA) medical centers and local Alzheimer's Association chapters. Based on comprehensive assessment, and needs prioritization, care coordinators collaboratively planned action steps (specific behavioral tasks) with each caregiver/person with dementia to address the dyad's identified unmet needs. Results show that 51 (54.8%) of 93 dyads reported a need for legal and financial services. Action steps related to legal and financial need included education or assistance with legal services (27.27%), nonhealth-related financial benefits (32.32%), health-related financial benefits (21.21%), financial management/planning (9.09%), and financial support (10.1%). Comparable numbers of action steps were directed to VA (41.4%) and non-VA (58.6%) services.

  13. Influence of Ga vacancies, Mn and O impurities on the ferromagnetic properties of GaN micro- and nanostructures

    NASA Astrophysics Data System (ADS)

    Guzmán, G.; Escudero, R.; Silva, R.; Herrera, M.

    2018-04-01

    We present a study of the influence of gallium vacancy (VGa) point defects on the ferromagnetic properties of GaN:Mn and GaN:Mn,O micro- and nanostructures. Results demonstrate that the generation of these point defects enhances the ferromagnetic signal of GaN:Mn microstructures, while incorporation of oxygen as an impurity inhibits this property. XPS measurements revealed that Mn impurities in ferromagnetic GaN:Mn samples mainly exhibit a valence state of 2+. Cathodoluminescence (CL) spectra from Mn-doped GaN samples displayed emissions centered at about 1.97 eV, attributed to transitions between the 4T1-6A1 states of the Mn2+ d orbitals, and emissions centered at 2.45 and 2.9 eV, associated with the presence of VGa. CL measurements also revealed a blue shift of the GaN band-edge emission generated by the expansion of the wurtzite lattice due to Mn incorporation, which was confirmed by XRD measurements. These latter measurements also revealed an amorphization of GaN:Mn due to the incorporation of oxygen as impurities. The GaN:Mn samples were synthesized by thermal evaporation of GaN and MnCO3 powders onto Ni0.8Cr0.2/Si(100) in a horizontal furnace operated at low vacuum. The residual air inside the system was used as a source of oxygen during the synthesis of Mn and O co-doped GaN nanostructures. Mn and O impurities were incorporated into the nanostructures at different concentrations by varying the growth temperature. Energy Dispersive Spectroscopy, XRD, and XPS measurements confirmed that the obtained samples predominantly consisted of GaN.

  14. Magnetic properties of solid solutions between BiCrO3 and BiGaO3 with perovskite structures

    NASA Astrophysics Data System (ADS)

    Belik, Alexei A.

    2015-04-01

    Magnetic properties of BiCr1-xGaxO3 perovskite-type solid solutions are reported, and a magnetic phase diagram is established. As-synthesized BiCrO3 and BiCr0.9Ga0.1O3 crystallize in a monoclinic (m) C2/c structure. The Néel temperature (TN) decreases from 111 K in BiCrO3 to 98 K in BiCr0.9Ga0.1O3, and spin-reorientation transition temperature increases from 72 K in BiCrO3 to 83 K in BiCr0.9Ga0.1O3. o-BiCr0.9Ga0.1O3 with a PbZrO3-type orthorhombic structure is obtained by heating m-BiCr0.9Ga0.1O3 up to 573 K in air; it shows similar magnetic properties with those of m-BiCr0.9Ga0.1O3. TN of BiCr0.8Ga0.2O3 is 81 K, and TN of BiCr0.7Ga0.3O3 is 63 K. Samples with x = 0.4, 0.5, 0.6 and 0.7 crystallize in a polar R3c structure. Long-range antiferromagnetic order with weak ferromagnetism is observed below TN = 56 K in BiCr0.6Ga0.4O3, TN = 36 K in BiCr0.5Ga0.5O3 and TN = 18 K in BiCr0.4Ga0.6O3. BiCr0.3Ga0.7O3 shows a paramagnetic behaviour because the Cr concentration is below the percolation threshold of 31%.

  15. GaN Based Electronics And Their Applications

    NASA Astrophysics Data System (ADS)

    Ren, Fan

    2002-03-01

    The Group III-nitrides were initially researched for their promise to fill the void for a blue solid state light emitter. Electronic devices from III-nitrides have been a more recent phenomenon. The thermal conductivity of GaN is three times that of GaAs. For high power or high temperature applications, good thermal conductivity is imperative for heat removal or sustained operation at elevated temperatures. The development of III-N and other wide bandgap technologies for high temperature applications will likely take place at the expense of competing technologies, such as silicon-on-insulator (SOI), at moderate temperatures. At higher temperatures (>300°C), novel devices and components will become possible. The automotive industry will likely be one of the largest markets for such high temperature electronics. One of the most noteworthy advantages for III-N materials over other wide bandgap semiconductors is the availability of AlGaN/GaN and InGaN/GaN heterostructures. A 2-dimensional electron gas (2DEG) has been shown to exist at the AlGaN/GaN interface, and heterostructure field effect transistors (HFETs) from these materials can exhibit 2DEG mobilities approaching 2000 cm2 / V?s at 300K. Power handling capabilities of 12 W/mm appear feasible, and extraordinary large signal performance has already been demonstrated, with a current state-of-the-art of >10W/mm at X-band. In this talk, high speed and high temperature AlGaN/GaN HEMTs as well as MOSHEMTs, high breakdown voltage GaN (>6KV) and AlGaN (9.7 KV) Schottky diodes, and their applications will be presented.

  16. Ohmic contacts to n-GaN formed by ion-implanted Si into p-GaN

    NASA Astrophysics Data System (ADS)

    Bao, Xichang; Xu, Jintong; Zhang, Wenjing; Wang, Ling; Chu, Kaihui; Li, Chao; Li, Xiangyang

    2009-07-01

    In this paper, we report the ohmic contact to n-GaN fabricated by implanting silicon into Mg-doped GaN using an alloy of Ti/Al/Ti/Au metallization. The used materials were grown on (001) sapphire substrates by metal-organic chemical-vapor deposition (MOCVD). The layer structure was comprised of a GaN buffer layer and followed by a 2 μm thickness Mg-doped GaN (Na=5×1017cm-3) and then double silicon implantation was performed in order to convert p-type GaN into n-type GaN films. The as-implanted samples were then thermal annealed at 1150 °C for 5 min in N2 ambient. The carrier concentration and Hall mobility were 3.13×1018 cm3 and 112 cm2/ (VÂ.s) measured by Hall method. Multilayer electrode of Ti (50 nm)/Al (50 nm)/Ti (30 nm)/Au (30 nm) was deposited on n-GaN using an electron-beam evaporation and contacts were formed by a N2 annealing technique ranging from 600 to 900 °C. After annealing lower than 700 °C, the contacts exhibited a rectifying behavior and became ohmic contact only after high temperature processes (>=700 °C). Specific contact resistance was as low as 9.58×10-4 ΩÂ.cm2 after annealing at 800 °C for 60 seconds. While annealing temperature is higher than 800 °C, the specific contact resistance becomes worse. This phenomenon is caused by the surface morphology degradation.

  17. Kinetic instability of AlGaN alloys during MBE growth under metal-rich conditions on m-plane GaN miscut towards the -c axis

    NASA Astrophysics Data System (ADS)

    Shirazi-HD, M.; Diaz, R. E.; Nguyen, T.; Jian, J.; Gardner, G. C.; Wang, H.; Manfra, M. J.; Malis, O.

    2018-04-01

    AlxGa1-xN layers with Al-composition above 0.6 (0.6 < x < 0.9) grown under metal-rich conditions by plasma-assisted molecular beam epitaxy on m-plane GaN miscut towards the -c axis are kinetically unstable. Even under excess Ga flux, the effective growth rate of AlGaN is drastically reduced, likely due to suppression of Ga-N dimer incorporation. The defect structure generated during these growth conditions is studied with energy dispersive x-ray spectroscopy scanning transmission electron microscopy as a function of Al flux. The AlGaN growth results in the formation of thin Al(Ga)N layers with Al-composition higher than expected and lower Al-composition AlGaN islands. The AlGaN islands have a flat top and are elongated along the c-axis (i.e., stripe-like shape). Possible mechanisms for the observed experimental results are discussed. Our data are consistent with a model in which Al-N dimers promote release of Ga-N dimers from the m-plane surface.

  18. Neuropathology and brain weight in traumatic-crush asphyxia.

    PubMed

    Al-Sarraj, Safa; Laxton, Ross; Swift, Ben; Kolar, Alexander J; Chapman, Rob C; Fegan-Earl, Ashley W; Cary, Nat R B

    2017-11-01

    Traumatic (crush) asphyxia is a rare condition caused by severe compression of the chest and trunk leading to often extreme so-called asphyxial signs, including cyanosis in head and neck regions, multiple petechiae, and subconjunctival haemorrhage as well as neurological manifestations. To investigate the neuropathology and brain weight in traumatic asphyxia caused by different accidents such as industrial accidents and road traffic collision. Post mortem records of 20 cases of traumatic asphyxia (TA) resulting from different causes of which four brains are available for comprehensive neuropathological examination. The expected brain weights for given body height and associated 95% confidence range were calculated according to the following formula: baseline brain weight (BBW) + body height x rate (g/cm). The 95% confidence range was calculated by adding and subtracting the standard error (SE) x 1.96 (7-8). There was a trend for higher brain weight in the TA cohort but it was not significant (1494 g vs 1404 g, p = 0.1). The upper limits of the brain weight of 95% confidence was 1680 g vs 1660 g, p = 0.9. The neuropathological examination of four available brains from the TA cohort showed severe congestion of blood vessels, perivascular haemorrhages and occasional βAPP deposits consistent with early axonal disruption. Brain examination is informative as part of investigation of TA. Developing ischaemic changes and an increase in brain weight are the most likely indicators of a prolonged period of patient's survival. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  19. Enhanced conversion efficiency in wide-bandgap GaNP solar cells

    DOE PAGES

    Sukrittanon, Supanee; Liu, Ren; Ro, Yun Goo; ...

    2015-10-12

    In this study, we demonstrate –2.05 eV dilute nitride GaNP solar cells on GaP substrates for potential use as the top junction in dual-junction integrated cells on Si. By adding a small amount of N into indirect-bandgap GaP, GaNP has several extremely important attributes: a direct-bandgap that is also tunable, and easily attained lattice-match with Si. Our best GaNP solar cell ([N] –1.8%, E g –2.05 eV) achieves an efficiency of 7.9%, even in the absence of a window layer. This GaNP solar cell's efficiency is 3× higher than the most efficient GaP solar cell to date and higher thanmore » other solar cells with similar direct bandgap (InGaP, GaAsP). Through a systematic study of the structural, electrical, and optical properties of the device, efficient broadband optical absorption and enhanced solar cell performance are demonstrated.« less

  20. 45 CFR 1610.9 - Accounting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Accounting. 1610.9 Section 1610.9 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL SERVICES CORPORATION USE OF NON-LSC FUNDS, TRANSFERS OF LSC FUNDS, PROGRAM INTEGRITY § 1610.9 Accounting. Funds received by a recipient from a source...

  1. Temperature dependence of quantized states in an InGaAs/GaAs strained asymmetric triangular quantum well

    NASA Astrophysics Data System (ADS)

    Chi, W. S.; Lin, D. Y.; Huang, Y. S.; Qiang, H.; Pollak, F. H.; Mathine, D. L.; Maracas, G. N.

    1996-03-01

    Photoreflectance (PR), contactless electroreflectance (CER) and piezoreflectance (PzR) measurements of an InGaAs/GaAs strained asymmetric triangular quantum well (ATQW) heterostructure as a function of temperature in the range of 20 to 300 K have been carried out. The structure was fabricated by molecular beam epitaxy using the digital alloy compositional grading method. A careful analysis of the PR, CER and PzR spectra has led to the identification of various excitonic transitions, mnH(L), between the mth conduction band state to the nth heavy(light)-hole band state. Comparison of the observed intersubband transitions with a theoretical calculation based on the envelope function model, including the effects of strain, provide a self-consistent check of the ATQW composition profile. The detailed study of the temperature dependence of the excitonic transition energies indicates that the potential profile of the ATQW varies at different temperatures. The parameters that describe the temperature dependence of 0268-1242/11/3/012/img8 are evaluated. The anomalous behaviour of the temperature dependence of the linewidth of 11H, 0268-1242/11/3/012/img9, is compared with recent results for GaAs/AlGaAs and InGaAs/GaAs symmetric rectangular quantum wells of comparable dimensions.

  2. Low-income minority and homeless mothers' perceptions of their 9-13 year-old children's weight status, diet, and health.

    PubMed

    Dammann, Kristen Wiig; Smith, Chery; Richards, Rickelle

    2011-01-01

    The purpose of this study was to examine low-income mothers' perceptions of their children's height and weight in relation to actual measures, and perceptions of dietary quality and health status. Demographic, anthropometric, and dietary quality/health status data were collected during a multi-phase nutrition research project with low-income Minnesotans, and a sub-set of non-pregnant mother-child dyads (mothers ages ≥ 18 years, children ages 9-13 years) were analyzed (n = 257). Participants were Caucasian, African American, American Indian, Hispanic, Asian, or Other/mixed race, and most were homeless. Relationships between maternal perceptions of their child's height and weight and the actual measures, and maternal perceptions of dietary quality and health status for the dyad, were examined using independent and paired samples t-tests, ANOVA, and paired samples correlations. Comparisons were also made by maternal and child body mass index (BMI) status and living situation. Mothers significantly underestimated their child's height and weight (-4.8 ± 13.9 cm, P = 0.000; -5.3 ± 8.5 kg, P = 0.000); greatest misperceptions of weight were among mothers of overweight/obese children (P = 0.000). Mothers not reporting estimates of their child's height and weight (n = 53) had higher BMIs (P = 0.029), and their children were younger (P = 0.000) and lighter (P = 0.021) compared to mothers who provided estimates. Inability to objectify children's weight status may contribute to the obesity epidemic affecting low-income minority populations. Underestimation of weight status may be influenced by cultural perceptions of body image and socioeconomic status.

  3. Europium gallium garnet (Eu3Ga5O12) and Eu3GaO6: Synthesis and material properties

    NASA Astrophysics Data System (ADS)

    Sawada, Kenji; Nakamura, Toshihiro; Adachi, Sadao

    2016-10-01

    Eu-Ga-O ternary compounds were synthesized from a mixture of cubic (c-) Eu2O3 and monoclinic Ga2O3 (β-Ga2O3) raw powders using the solid-state reaction method by calcination at Tc = 1200 °C. The structural and optical properties of the Eu-Ga-O ternary compounds were investigated using X-ray diffraction analysis, photoluminescence (PL) analysis, PL excitation (PLE) spectroscopy, and Raman scattering measurements. Stoichiometric compounds such as cubic Eu3Ga5O12 (EGG) and orthorhombic Eu3GaO6 were synthesized using molar ratios of x = 0.375 and 0.75 [x≡Eu2O3/(Eu2O3 + Ga2O3)], respectively, together with the end-point binary compounds β-Ga2O3 (x = 0) and monoclinic (m-) Eu2O3 (x = 1.0). The structural change from "cubic" to "monoclinic" in Eu2O3 is due to the structural phase transition occurring at Tc ≥ 1050 °C. In principle, the perovskite-type EuGaO3 and monoclinic Eu4Ga2O9 can also be synthesized at x = 0.5 and 0.667, respectively; however, such stoichiometric compounds could not be synthesized in this study. The PL and PLE properties of EGG and Eu3GaO6 were studied in detail. The temperature dependence of the PL spectra was observed through measurements carried out between T = 20 and 300 K and explained using a newly developed model. Raman scattering measurements were also performed on the Eu-Ga-O ternary systems over the entire composition range from x = 0 (β-Ga2O3) to 1.0 (m-Eu2O3).

  4. Legal briefing: organ donation and allocation.

    PubMed

    Pope, Thaddeus Mason

    2010-01-01

    This issue's "Legal Briefing" column covers legal developments pertaining to organ donation and allocation. This topic has been the subject of recent articles in JCE. Organ donation and allocation have also recently been the subjects of significant public policy attention. In the past several months, legislatures and regulatory agencies across the United States and across the world have changed, or considered changing, the methods for procuring and distributing human organs for transplantation. Currently, in the U.S., more than 100,000 persons are waiting for organ transplantation. In China, more than 1.5 million people are waiting. Given the chronic shortage of available organs (especially kidneys and livers) relative to demand, the primary focus of most legal developments has been on increasing the rate of donation. These and related developments are usefully divided into the following 12 topical categories: 1. Revised Uniform Anatomical Gift Act. 2. Presumed Consent and Opt-Out. 3. Mandated Choice. 4. Donation after Cardiac Death. 5. Payment and Compensation. 6. Donation by Prisoners. 7. Donor Registries. 8. Public Education. 9. Other Procurement Initiatives. 10. Lawsuits and Liability. 11. Trafficking and Tourism. 12. Allocation and Distribution.

  5. Civil Legal Services and Medical-Legal Partnerships Needed by the Homeless Population: A National Survey.

    PubMed

    Tsai, Jack; Jenkins, Darlene; Lawton, Ellen

    2017-03-01

    To examine civil legal needs among people experiencing homelessness and the extent to which medical-legal partnerships exist in homeless service sites, which promote the integration of civil legal aid professionals into health care settings. We surveyed a national sample of 48 homeless service sites across 26 states in November 2015. The survey asked about needs, attitudes, and practices related to civil legal issues, including medical-legal partnerships. More than 90% of the homeless service sites reported that their patients experienced at least 1 civil legal issue, particularly around housing, employment, health insurance, and disability benefits. However, only half of all sites reported screening patients for civil legal issues, and only 10% had a medical-legal partnership. The large majority of sites reported interest in receiving training on screening for civil legal issues and developing medical-legal partnerships. There is great need and potential to deploy civil legal services in health settings to serve unstably housed populations. Training homeless service providers how to screen for civil legal issues and how to develop medical-legal partnerships would better equip them to provide comprehensive care.

  6. Annealing effect on effective mass of two-dimensional electrons in InGaAsN/GaAsSb type II quantum well

    NASA Astrophysics Data System (ADS)

    Kawamata, Shuichi; Tanaka, Sho; Hibino, Akira; Kawamura, Yuichi

    2018-03-01

    The InP-based InGaAs/GaAsSb type II multiple quantum well is the system for developing optical devices for 2 – 3 μm wavelength regions. By doping nitrogen into InGaAs layers, the system becomes effective to fabricate the optical devices with longer wavelength. The epitaxial layers of InGaAsN/GaAsSb on InP substrates are grown by the molecular beam epitaxy. The electrical resistance has been measured as a function of the magnetic field up to 9 Tesla at several temperatures between 2 and 8 K. The effective mass is obtained from the temperature dependence of the amplitude of the Shubnikov-de Haas oscillations. We have reported the nitrogen concentration dependence of the effective mass on the InGaAsN/GaAsSb type II system. The effective mass increases as the nitrogen concentration increases from 0.0 to 1.5 %. In this report, the annealing effect on the effective mass is investigated. The effective mass decreases by the annealing. This result suggests that some amount of nitrogen atoms of the InGaAsN layers are considered to diffuse to the GaAsSb layers by the annealing.

  7. The Legal Assistant.

    ERIC Educational Resources Information Center

    Steely, Robert D.

    Following a review of the history of the legal assistant profession and the present status of legal assistant education, this document reports a study of the need for a legal assistant program at Kellogg Community College (KCC). A survey questionnaire was distributed to 106 private attorneys, financial institutions, businesses and industries,…

  8. Dementia and legal competency.

    PubMed

    Filaković, Pavo; Erić, Anamarija Petek; Mihanović, Mate; Glavina, Trpimir; Molnar, Sven

    2011-06-01

    The legal competency or capability to exercise rights is level of judgment and decision-making ability needed to manage one's own affairs and to sign official documents. With some exceptions, the person entitles this right in age of majority. It is acquired without legal procedures, however the annulment of legal capacity requires a juristic process. This resolution may not be final and could be revoked thorough the procedure of reverting legal capacity - fully or partially. Given the increasing number of persons with dementia, they are often subjects of legal expertise concerning their legal capacity. On the other part, emphasis on the civil rights of mentally ill also demands their maximal protection. Therefore such distinctive issue is approached with particular attention. The approach in determination of legal competency is more focused on gradation of it's particular aspects instead of existing dual concept: legally capable - legally incapable. The main assumption represents how person with dementia is legally capable and should enjoy all the rights, privileges and obligations as other citizens do. The aspects of legal competency for which person with dementia is going to be deprived, due to protection of one's rights and interests, are determined in legal procedure and then passed over to the guardian decided by court. Partial annulment of legal competency is measure applied when there is even one existing aspect of preserved legal capability (pension disposition, salary or pension disposition, ability of concluding contract, making testament, concluding marriage, divorce, choosing whereabouts, independent living, right to vote, right to decide course of treatment ect.). This measure is most often in favour of the patient and rarely for protection of other persons and their interests. Physicians are expected to precisely describe early dementia symptoms which may influence assessment of specific aspects involved in legal capacity (memory loss, impaired task

  9. Crash Fatality Rates After Recreational Marijuana Legalization in Washington and Colorado.

    PubMed

    Aydelotte, Jayson D; Brown, Lawrence H; Luftman, Kevin M; Mardock, Alexandra L; Teixeira, Pedro G R; Coopwood, Ben; Brown, Carlos V R

    2017-08-01

    To evaluate motor vehicle crash fatality rates in the first 2 states with recreational marijuana legalization and compare them with motor vehicle crash fatality rates in similar states without recreational marijuana legalization. We used the US Fatality Analysis Reporting System to determine the annual numbers of motor vehicle crash fatalities between 2009 and 2015 in Washington, Colorado, and 8 control states. We compared year-over-year changes in motor vehicle crash fatality rates (per billion vehicle miles traveled) before and after recreational marijuana legalization with a difference-in-differences approach that controlled for underlying time trends and state-specific population, economic, and traffic characteristics. Pre-recreational marijuana legalization annual changes in motor vehicle crash fatality rates for Washington and Colorado were similar to those for the control states. Post-recreational marijuana legalization changes in motor vehicle crash fatality rates for Washington and Colorado also did not significantly differ from those for the control states (adjusted difference-in-differences coefficient = +0.2 fatalities/billion vehicle miles traveled; 95% confidence interval = -0.4, +0.9). Three years after recreational marijuana legalization, changes in motor vehicle crash fatality rates for Washington and Colorado were not statistically different from those in similar states without recreational marijuana legalization. Future studies over a longer time remain warranted.

  10. Enhanced sheet carrier densities in polarization controlled AlInN/AlN/GaN/InGaN field-effect transistor on Si (111)

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

    Hennig, J., E-mail: jonas.hennig@ovgu.de; Dadgar, A.; Witte, H.

    2015-07-15

    We report on GaN based field-effect transistor (FET) structures exhibiting sheet carrier densities of n = 2.9 10{sup 13} cm{sup −2} for high-power transistor applications. By grading the indium-content of InGaN layers grown prior to a conventional GaN/AlN/AlInN FET structure control of the channel width at the GaN/AlN interface is obtained. The composition of the InGaN layer was graded from nominally x{sub In} = 30 % to pure GaN just below the AlN/AlInN interface. Simulations reveal the impact of the additional InGaN layer on the potential well width which controls the sheet carrier density within the channel region of the devices.more » Benchmarking the In{sub x}Ga{sub 1−x}N/GaN/AlN/Al{sub 0.87}In{sub 0.13}N based FETs against GaN/AlN/AlInN FET reference structures we found increased maximum current densities of I{sub SD} = 1300 mA/mm (560 mA/mm). In addition, the InGaN layer helps to achieve broader transconductance profiles as well as reduced leakage currents.« less

  11. Query Expansion for Noisy Legal Documents

    DTIC Science & Technology

    2008-11-01

    9] G. Salton (ed). The SMART retrieval system experiments in automatic document processing. 1971. [10] H. Schutze and J . Pedersen. A cooccurrence...Language Modeling and Information Retrieval. http://www.lemurproject.org. [2] J . Baron, D. Lewis, and D. Oard. TREC 2006 legal track overview. In...Retrieval, 1993. [8] J . Rocchio. Relevance feedback in information retrieval. In The SMART retrieval system experiments in automatic document processing, 1971

  12. An exploratory study of the health harms and utilisation of health services of frequent legal high users under the interim regulated legal high market in central Auckland.

    PubMed

    Wilkins, Chris; Prasad, Jitesh; Wong, K C; Rychert, Marta; Graydon-Guy, Thomas

    2016-03-11

    To explore health problems and the accessing of health services by frequent legal high users under an interim regulated legal market in central Auckland. Frequent legal high users (monthly+) were recruited from outside eight randomly-selected, licensed, legal high stores in central Auckland from 23 April-7 May, 2014. Eligible participants were emailed a unique invitation to complete an on-line survey; 105 completed the survey. Twenty-seven percent had suffered mental illness during their lifetimes. Eighty percent used synthetic cannabinoids (SC), and 20% 'party pills'. Forty-seven percent of SC users used daily or more often. Other drugs used included alcohol (80%), cannabis (59%), 'ecstasy' (18%) and methamphetamine (15%). Fifty-eight percent of SC users were classified as SC dependent. The most common problems reported from SC use were: insomnia (29%); 'vomiting/nausea' (25%); 'short temper/agitation' (21%); 'anxiety' (21%); 'strange thoughts' (16%); and 'heart palpitations' (14%). The health services most commonly accessed by SC users were: a 'doctor/GP' (9%); 'counsellor' (9%); 'DrugHelp/MethHelp' websites (7%); 'Alcohol & Drug Helpline' (4%); 'ambulance' (3%); 'A&E' (3%); and hospitalisation (3%). Frequent use of interim licensed SC products was associated with health problems, including dependency. Further research is required to determine the health risks of these products.

  13. Anti-legal attitude toward abortion among abortion patients in the United States.

    PubMed

    Thomas, Rachel G; Norris, Alison H; Gallo, Maria F

    2017-11-01

    To measure the prevalence of believing that abortion should be illegal in all or most cases among women obtaining an abortion in the United States and to identify correlates of holding this belief. Study population was drawn from the nationally-representative 2008 Abortion Patient Survey. The primary outcome was having an anti-legal abortion attitude, defined as agreeing that abortion should be illegal in all or most cases. We assessed potential correlates in bivariable and multivariable analyses using weights to account for the complex sampling. A total of 4769 abortion patients completed the survey module containing the question on abortion legality, of which 4492 (94.2%) had non-missing data for the outcome. Overall, 4.1% of patients (N=183) reported an anti-legal abortion attitude. Correlates of having anti-legal attitude included being married, at <200% federal poverty level, fundamentalist, contraception non-use, no abortion history, perceiving the pregnancy with ambivalence or as unintended, and using misoprostol or another product on their own to bring back their period or end the pregnancy. Abortion patients who do not believe abortion should be legal appear to differ substantially from women who are more supportive of legality. Findings raise important questions about this subset of patients, including whether possible discordance between patient beliefs and behavior could influence their use of medical abortion or other products. Some abortion patients do not agree with abortion legality, and this subset could experience a degree of cognitive dissonance, which could influence the method by which they seek to abort. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. AlGaAs/InGaAs/AlGaAs double pulse doped pseudomorphic high electron mobility transistor structures on InGaAs substrates

    NASA Astrophysics Data System (ADS)

    Hoke, W. E.; Lyman, P. S.; Mosca, J. J.; McTaggart, R. A.; Lemonias, P. J.; Beaudoin, R. M.; Torabi, A.; Bonner, W. A.; Lent, B.; Chou, L.-J.; Hsieh, K. C.

    1997-10-01

    Double pulse doped AlGaAs/InGaAs/AlGaAs pseudomorphic high electron mobility transistor (PHEMT) structures have been grown on InxGa1-xAs (x=0.025-0.07) substrates using molecular beam epitaxy. A strain compensated, AlGaInAs/GaAs superlattice was used for improved resistivity and breakdown. Excellent electrical and optical properties were obtained for 110-Å-thick InGaAs channel layers with indium concentrations up to 31%. A room temperature mobility of 6860 cm2/V s with 77 K sheet density of 4.0×1012cm-2 was achieved. The InGaAs channel photoluminescence intensity was equivalent to an analogous structure on a GaAs substrate. To reduce strain PHEMT structures with a composite InGaP/AlGaAs Schottky layer were also grown. The structures also exhibited excellent electrical and optical properties. Transmission electron micrographs showed planar channel interfaces for highly strained In0.30Ga0.70As channel layers.

  15. Legal Care as Part of Health Care: The Benefits of Medical-Legal Partnership.

    PubMed

    Murphy, Johnna S; Lawton, Ellen M; Sandel, Megan

    2015-10-01

    Many of the social determinants of health are rooted in legal problems. Medical-legal partnerships (MLPs) have the potential to positively change clinical systems. This change can be accomplished by integrating legal staff into health care clinics to educate staff and residents on social determinants of health and their legal origins. When the MLP team works directly with patients to identify and address legal needs that improve health outcomes, and incorporate legal insights and solutions into health care practice where the patient population is overwhelmingly impacted by social conditions, outcomes are beneficial to children and families. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Constitutionally-Legal Policy as Base Type of Legal Policy of Russia

    ERIC Educational Resources Information Center

    Anichkin, Eugene S.

    2016-01-01

    The article deals with reasons for formation, nature and specifics of the constitutionally legal policy of modern Russia. The special attention is spared to the exposure of the aim, long-term and short-term tasks, and principles of national constitutionally legal policy. The functions of constitutionally legal policy are separately considered:…

  17. A genome-wide association study for body weight in Japanese Thoroughbred racehorses clarifies candidate regions on chromosomes 3, 9, 15, and 18

    PubMed Central

    TOZAKI, Teruaki; KIKUCHI, Mio; KAKOI, Hironaga; HIROTA, Kei-ichi; NAGATA, Shun-ichi

    2017-01-01

    ABSTRACT Body weight is an important trait to confirm growth and development in humans and animals. In Thoroughbred racehorses, it is measured in the postnatal, training, and racing periods to evaluate growth and training degrees. The body weight of mature Thoroughbred racehorses generally ranges from 400 to 600 kg, and this broad range is likely influenced by environmental and genetic factors. Therefore, a genome-wide association study (GWAS) using the Equine SNP70 BeadChip was performed to identify the genomic regions associated with body weight in Japanese Thoroughbred racehorses using 851 individuals. The average body weight of these horses was 473.9 kg (standard deviation: 28.0) at the age of 3, and GWAS identified statistically significant SNPs on chromosomes 3 (BIEC2_808466, P=2.32E-14), 9 (BIEC2_1105503, P=1.03E-7), 15 (BIEC2_322669, P=9.50E-6), and 18 (BIEC2_417274, P=1.44E-14), which were associated with body weight as a quantitative trait. The genomic regions on chromosomes 3, 9, 15, and 18 included ligand-dependent nuclear receptor compressor-like protein (LCORL), zinc finger and AT hook domain containing (ZFAT), tribbles pseudokinase 2 (TRIB2), and myostatin (MSTN), respectively, as candidate genes. LCORL and ZFAT are associated with withers height in horses, whereas MSTN affects muscle mass. Thus, the genomic regions identified in this study seem to affect the body weight of Thoroughbred racehorses. Although this information is useful for breeding and growth management of the horses, the production of genetically modified animals and gene doping (abuse/misuse of gene therapy) should be prohibited to maintain horse racing integrity. PMID:29270069

  18. Department of Legal Services

    Science.gov Websites

    The Department of Legal Services ("DLS") is a dependency of the Secretariat for Legal Affairs of the OAS General Secretariat. www.oas.org/en/sla DLS provides legal advice on: interpretation of Secretariat for Legal Affairs Inter-American Commission on Human Rights Inter-American Court of Human Rights

  19. Analysis - what is legal medicine?

    PubMed

    Beran, Roy G

    2008-04-01

    Legal medicine addresses the interface between medicine and law in health care. The Australian College of Legal Medicine (ACLM) established itself as the peak body in legal and forensic medicine in Australia. It helped establish the Expert Witness Institute of Australia (EWIA), the legal medicine programme at Griffith University and contributes to government enquiries. Public health, disability assessment, competing priorities of privacy verses notification and determination of fitness for a host of pursuits are aspects of legal medicine. Complementing the EWIA, the ACLM runs training programmes emphasising legal medicine skills additional to clinical practice, advocating clinical relevance. Assessment of athletes' fitness and ensuring that prohibited substances are not inadvertently prescribed represent a growing area of legal medicine. Ethical consideration of health care should respect legal medicine principles rather than armchair commentary. International conventions must be respected by legal medicine and dictate physicians' obligations. The NSW courts imposed a duty to provide emergency medical care. Migration and communicable diseases are aspects of legal medicine. Police surgeons provide a face to legal medicine (which incorporates forensic medicine) underpinning its public perception of specialty recognition. Legal medicine deserves its place as a medical specialty in its own right.

  20. Legal protections to promote response willingness among the local public health workforce.

    PubMed

    Rutkow, Lainie; Vernick, Jon S; Thompson, Carol B; Piltch-Loeb, Rachael; Barnett, Daniel J

    2015-04-01

    The legal environment may improve response willingness among local health department (LHD) workers. We examined whether 3 hypothetical legal protections influence LHD workers' self-reported response willingness for 4 emergency scenarios and whether specific demographic factors are associated with LHD workers' response willingness given these legal protections. Our 2011-2012 survey included questions on demographics and about attitudes and beliefs regarding LHD workers' willingness to respond to 4 emergency scenarios given specific legal protections (i.e., ensuring priority health care for workers' families, granting workers access to mental health services, and guaranteeing access to personal protective equipment). Data were collected from 1238 LHD workers in 3 states. Across scenarios, between 60% and 83% of LHD workers agreed that they would be more willing to respond given the presence of 1 of the 3 hypothetical legal protections. Among the 3 legal protections, a guarantee of personal protective equipment elicited the greatest agreement with improved response willingness. Specific legal protections augment a majority of LHD workers' response willingness. Policymakers must, however, balance improved response willingness with other considerations, such as the ethical implications of prioritizing responders over the general public. (Disaster Med Public Health Preparedness. 2015;9:98-102).

  1. Characterization of bulk traps and interface states in AlGaN/GaN heterostructure under proton irradiation

    NASA Astrophysics Data System (ADS)

    Zheng, Xue-Feng; Dong, Shuai-Shuai; Ji, Peng; Wang, Chong; He, Yun-Long; Lv, Ling; Ma, Xiao-Hua; Hao, Yue

    2018-06-01

    This paper provides a systematic study on the bulk traps and interface states in a typical AlGaN/GaN Schottky structure under proton irradiation. After 3 MeV proton irradiation with a dose of 5 × 1014 H+/cm2, a positive flat band voltage shift of 0.3 V is observed according to the capacitance-voltage (C-V) measurements. Based on this, the distribution of electrons across AlGaN and GaN layers is extracted. Associated with the numerical calculation, direct experimental evidences demonstrate that the bulk traps within the AlGaN layer dominate the carrier removal effect under proton irradiation. Furthermore, the effects of proton irradiation on AlGaN/GaN interface states were investigated by utilizing the frequency dependent conductance technique. The time constants are extracted, which increase from 1.10-2.53 μs to 3.46-37 μs after irradiation. Meanwhile, it shows that the density of interface states increases from 9.45 × 1011-1.70 × 1013 cm-2.eV-1 to 1.8 × 1012-1.8 × 1013 cm-2.eV-1 with an increase in trap activation energy from 0.34 eV-0.32 eV to 0.41 eV-0.35 eV after irradiation. The Coulomb scattering effect of electron trapping at interface states with deeper energy levels is utilized to explain the mobility degradation in this paper.

  2. Photoelectrochemical response of GaN, InGaN, and GaNP nanowire ensembles

    NASA Astrophysics Data System (ADS)

    Philipps, Jan M.; Hölzel, Sara; Hille, Pascal; Schörmann, Jörg; Chatterjee, Sangam; Buyanova, Irina A.; Eickhoff, Martin; Hofmann, Detlev M.

    2018-05-01

    The photoelectrochemical responses of GaN, GaNP, and InGaN nanowire ensembles are investigated by the electrical bias dependent photoluminescence, photocurrent, and spin trapping experiments. The results are explained in the frame of the surface band bending model. The model is sufficient for InGaN nanowires, but for GaN nanowires the electrochemical etching processes in the anodic regime have to be considered additionally. These processes lead to oxygen rich surface (GaxOy) conditions as evident from energy dispersive X-ray fluorescence. For the GaNP nanowires, a bias dependence of the carrier transfer to the electrolyte is not reflected in the photoluminescence response, which is tentatively ascribed to a different origin of radiative recombination in this material as compared to (In)GaN. The corresponding consequences for the applications of the materials for water splitting or pH-sensing will be discussed.

  3. Codoping characteristics of Zn with Mg in GaN

    NASA Astrophysics Data System (ADS)

    Kim, K. S.; Han, M. S.; Yang, G. M.; Youn, C. J.; Lee, H. J.; Cho, H. K.; Lee, J. Y.

    2000-08-01

    The doping characteristics of Mg-Zn codoped GaN films grown by metalorganic chemical vapor deposition are investigated. By means of the concept of Mg-Zn codoping technique, we have grown p-GaN showing a low electrical resistivity (0.72 Ω cm) and a high hole concentration (8.5×1017cm-3) without structural degradation of the film. It is thought that the codoping of Zn atoms with Mg raises the Mg activation ratio by reducing the hydrogen solubility in p-GaN. In addition, the measured specific contact resistance of Mg-Zn codoped GaN film is 5.0×10-4 Ω cm2, which is one order of magnitude lower than that of Mg doped only GaN film (1.9×10-3 Ω cm2).

  4. Influence of internal electric fields on band gaps in short period GaN/GaAlN and InGaN/GaN polar superlattices

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

    Gorczyca, I., E-mail: iza@unipress.waw.pl; Skrobas, K.; Suski, T.

    2015-08-21

    The electronic structures of short period mGaN/nGa{sub y}Al{sub 1−y}N and mIn{sub y}Ga{sub 1-y}N/nGaN superlattices grown along the wurtzite c axis have been calculated for different alloy compositions y and various small numbers m of well- and n of barrier-monolayers. The general trends in gap behavior can, to a large extent, be related to the strength of the internal electric field, E, in the GaN and InGaN quantum wells. In the GaN/GaAlN superlattices, E reaches 4 MV/cm, while in the InGaN/GaN superlattices, values as high as E ≈ 6.5 MV/cm are found. The strong electric fields are caused by spontaneous and piezoelectric polarizations,more » the latter contribution dominating in InGaN/GaN superlattices. The influence of different arrangements of In atoms (indium clustering) on the band gap values in InGaN/GaN superlattices is examined.« less

  5. Influence of internal electric fields on band gaps in short period GaN/GaAlN and InGaN/GaN polar superlattices

    NASA Astrophysics Data System (ADS)

    Gorczyca, I.; Skrobas, K.; Suski, T.; Christensen, N. E.; Svane, A.

    2015-08-01

    The electronic structures of short period mGaN/nGayAl1-yN and mInyGa1-yN/nGaN superlattices grown along the wurtzite c axis have been calculated for different alloy compositions y and various small numbers m of well- and n of barrier-monolayers. The general trends in gap behavior can, to a large extent, be related to the strength of the internal electric field, E, in the GaN and InGaN quantum wells. In the GaN/GaAlN superlattices, E reaches 4 MV/cm, while in the InGaN/GaN superlattices, values as high as E ≈ 6.5 MV/cm are found. The strong electric fields are caused by spontaneous and piezoelectric polarizations, the latter contribution dominating in InGaN/GaN superlattices. The influence of different arrangements of In atoms (indium clustering) on the band gap values in InGaN/GaN superlattices is examined.

  6. Photoreflectance from GaAs and GaAs/GaAs interfaces

    NASA Astrophysics Data System (ADS)

    Sydor, Michael; Angelo, James; Wilson, Jerome J.; Mitchel, W. C.; Yen, M. Y.

    1989-10-01

    Photoreflectance from semi-insulating GaAs, and GaAs/GaAs interfaces, is discussed in terms of its behavior with temperature, doping, epilayer thickness, and laser intensity. Semi-insulating substrates show an exciton-related band-edge signal below 200 K and an impurity-related photoreflectance above 400 K. At intermediate temperatures the band-edge signal from thin GaAs epilayers contains a contribution from the epilayer-substrate interface. The interface effect depends on the epilayer's thickness, doping, and carrier mobility. The effect broadens the band-edge photoreflectance by 5-10 meV, and artifically lowers the estimates for the critical-point energy, ECP, obtained through the customary third-derivative functional fit to the data.

  7. Legal Services: Judge Advocate Legal Services

    DTIC Science & Technology

    1996-09-30

    14–14, page 41 Publicity • 14–15, page 41 Insignia • 14–16, page 41 Chapter 15 Contract Law Attorneys, page 43 General • 15–1, page 43 General...Duties • 15–2, page 43 Management • 15–3, page 43 Principles of contract law practice • 15–4, page 43 Contract disputes and litigation support • 15–5...legal matters; and (2) Resolving their personal legal problems whenever possible. m. Contract law responsibilities. TJAG will provide— (1) Technical

  8. Effect of high density H 2 plasmas on InGaP/GaAs and AlGaAs/GaAs HEMTs

    NASA Astrophysics Data System (ADS)

    Ren, F.; Kopf, R. F.; Kuo, J. M.; Lothian, J. R.; Lee, J. W.; Pearton, S. J.; Shul, R. J.; Constantine, C.; Johnson, D.

    1998-05-01

    InGaP/GaAs and AlGaAs/GaAs high electron mobility transistors have been exposed to inductively coupled plasma or electron cyclotron resonance H 2 plasmas as a function of pressure, source power and rf chuck power. The transconductance, gate ideality factor and saturated drain-source current are all degraded by the plasma treatment. Two mechanisms are identified: passivation of Si dopants in the InGaP or AlGaAs donor layers by H 0 and lattice disorder created by H + and H 2+ ion bombardment. HEMTs are found to be more susceptible to plasma-induced degradation than heterojunction bipolar transistors.

  9. Reduction of gate leakage current on AlGaN/GaN high electron mobility transistors by electron-beam irradiation.

    PubMed

    Oh, S K; Song, C G; Jang, T; Kim, Kwang-Choong; Jo, Y J; Kwak, J S

    2013-03-01

    This study examined the effect of electron-beam (E-beam) irradiation on the AIGaN/GaN HEMTs for the reduction of gate leakage. After E-beam irradiation, the gate leakage current significantly decreased from 2.68 x 10(-8) A to 4.69 x 10(-9) A at a drain voltage of 10 V. The maximum drain current density of the AIGaN/GaN HEMTs with E-beam irradiation increased 14%, and the threshold voltage exhibited a negative shift, when compared to that of the AIGaN/GaN HEMTs before E-beam irradiation. These results strongly suggest that the reduction of gate leakage current resulted from neutralization nitrogen vacancies and removing of oxygen impurities.

  10. Same-sex legal marriage and psychological well-being: findings from the California Health Interview Survey.

    PubMed

    Wight, Richard G; Leblanc, Allen J; Lee Badgett, M V

    2013-02-01

    We examined whether same-sex marriage was associated with nonspecific psychological distress among self-identified lesbian, gay, and bisexual adults, and whether it had the potential to offset mental health disparities between lesbian, gay, and bisexual persons and heterosexuals. Population-based data (weighted) were from the 2009 adult (aged 18-70 years) California Health Interview Survey. Within-group analysis of lesbian, gay, and bisexual persons included 1166 individuals (weighted proportion = 3.15%); within-group heterosexual analysis included 35 608 individuals (weighted proportion = 96.58%); and pooled analysis of lesbian, gay, and bisexual persons and heterosexuals included 36 774 individuals. Same-sex married lesbian, gay, and bisexual persons were significantly less distressed than lesbian, gay, and bisexual persons not in a legally recognized relationship; married heterosexuals were significantly less distressed than nonmarried heterosexuals. In adjusted pairwise comparisons, married heterosexuals had the lowest psychological distress, and lesbian, gay, and bisexual persons who were not in legalized relationships had the highest psychological distress (P < .001). Psychological distress was not significantly distinguishable among same-sex married lesbian, gay, and bisexual persons, lesbian, gay, and bisexual persons in registered domestic partnerships, and heterosexuals. Being in a legally recognized same-sex relationship, marriage in particular, appeared to diminish mental health differentials between heterosexuals and lesbian, gay, and bisexual persons. Researchers must continue to examine potential health benefits of same-sex marriage, which is at least in part a public health issue.

  11. HTA and its legal issues: a framework for identifying legal issues in health technology assessment.

    PubMed

    Widrig, Daniel; Tag, Brigitte

    2014-12-01

    Legal analysis can highlight important issues that are relevant when deciding whether a medical technology should be implemented or reimbursed. Literature and studies show that even though the law is an acknowledged part of health technology assessment (HTA), legal issues are rarely considered in practice. One reason for this may be the lack of knowledge about the diversity of legal issues that are relevant for HTA. Therefore, this contribution aims primarily to identify and then explain the relevant legal issues in HTA. This study offers a framework for identifying the legal issues in HTAs in different jurisdictions and provides a basis for further research. After extensive literature search, the authors review Swiss health law to identify legal issues that are relevant to HTA. The authors then categorize these legal issues using a framework with an inside and outside perspective. Finally, they explain a selection of these legal issues with several examples. This study reveals numerous legal issues that are relevant for HTA and underlines the necessity of incorporating legal analysis in HTAs. The suggested perspectival framework in this study provides a basis to structure the legal analysis. The identified legal issues are relevant in other countries and the perspectival framework is transferable to other jurisdictions. The article underlines the importance of in-depth discussion about the role of law in HTA. It provides a structured overview of the legal issues in HTA and suggests a development of more concrete instruments toward a standardized legal technology assessment.

  12. Medico legal issues.

    PubMed

    Mackenzie, Geraldine; Carter, Hugh

    2010-01-01

    This chapter gives an educational overview of: * An awareness of the legal issues involved in health informatics * The need for the privacy and security of the patient record * The legal consequences of a breach of the security of the patient record * The concept of privacy law and what precautions ought to be taken to minimize legal liability for a breach of privacy and/or confidentiality.

  13. 45 CFR 1634.9 - Selection criteria.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Selection criteria. 1634.9 Section 1634.9 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL SERVICES CORPORATION COMPETITIVE BIDDING FOR GRANTS AND CONTRACTS § 1634.9 Selection criteria. (a) The criteria to be used to select among...

  14. Rapid thermal anneal in InP, GaAs and GaAs/GaAlAs

    NASA Astrophysics Data System (ADS)

    Descouts, B.; Duhamel, N.; Godefroy, S.; Krauz, P.

    Ion implantation in semiconductors provides a doping technique with several advantages over more conventional doping methods and is now extensively used for device applications, e.g. field effect transistors (MESFET GaAs, MIS (InP), GaAs/GaAlAs heterojunction bipolar transistors (HBT). Because of the lattice disorder produced by the implantation, the dopant must be made electrically active by a postimplant anneal. As the device performances are very dependent on its electrical characteristics, the anneal is a very important stage of the process. Rapid anneal is known to provide less exodiffusion and less induffusion of impurities compared to conventional furnace anneal, so this technique has been used in this work to activate an n-type dopant (Si) in InP and a p-type dopant (Mg) in GaAs and GaAs/GaAIAs. These two ions have been chosen to realize implanted MIS InP and the base contacts for GaAs/GaAlAs HBTs. The experimental conditions to obtain the maximum electrical activity in these two cases will be detailed. For example, although we have not been able to obtain a flat profile in Mg + implanted GaAs/GaAlAs heterostructure by conventional thermal anneal, rapid thermal anneal gives a flat hole profile over a depth of 0.5 μm with a concentration of 1 x 10 19 cm -3.

  15. Nanoblast synthesis and consolidation of (La0.8Sr0.2)(Ga0.9Mg0.1)O(3-delta) under Spark plasma sintering conditions.

    PubMed

    Vasylkiv, Oleg; Borodianska, Hanna; Badica, Petre; Zhen, Yongda; Tok, Alfred

    2009-01-01

    Four-cation nanograined strontium and magnesium doped lanthanum gallate (La0.8Sr0.2) (Ga0.9Mg0.1)O(3-delta) (LSGM) and its composite with 2 wt% of ceria (LSGM-Ce) were prepared. Morphologically homogeneous nanoreactors, i.e., complex intermediate metastable aggregates of desired composition were assembled by spray atomization technique, and subsequently loaded with nanoparticles of highly energetic C3H6N6O6. Rapid nanoblast calcination technique was applied and the final composition was synthesized within the preliminary localized volumes of each single nanoreactor on the first step of spark plasma treatment. Subsequent SPS consolidations of nanostructured extremely active LSGM and LSGM-Ce powders were achieved by rapid treatment under pressures of 90-110 MPa. This technique provided the heredity of the final structure of nanosize multimetal oxide, allowed the prevention of the uncontrolled agglomeration during multicomponent aggregates assembling, subsequent nanoblast calcination, and final ultra-rapid low-temperature SPS consolidation of nanostructured ceramics. LaSrGaMgCeO(3-delta) nanocrystalline powder consisting of approximately 11 nm crystallites was consolidated to LSGM-Ce nanoceramic with average grain size of approximately 14 nm by low-temperature SPS at 1250 degrees C. Our preliminary results indicate that nanostructured samples of (La0.8Sr0.2)(Ga0.9Mg0.1)O(3-delta) with 2 wt% of ceria composed of approximataley 14 nm grains can exhibit giant magnetoresistive effect in contrast to the usual paramagnetic properties measured on the samples with larger grain size.

  16. AlGaN-Cladding-Free m-Plane InGaN/GaN Laser Diodes with p-Type AlGaN Etch Stop Layers

    NASA Astrophysics Data System (ADS)

    Farrell, Robert M.; Haeger, Daniel A.; Hsu, Po Shan; Hardy, Matthew T.; Kelchner, Kathryn M.; Fujito, Kenji; Feezell, Daniel F.; Mishra, Umesh K.; DenBaars, Steven P.; Speck, James S.; Nakamura, Shuji

    2011-09-01

    We present a new method of improving the accuracy and reproducibility of dry etching processes for ridge waveguide InGaN/GaN laser diodes (LDs). A GaN:Al0.09Ga0.91N etch rate selectivity of 11:1 was demonstrated for an m-plane LD with a 40 nm p-Al0.09Ga0.91N etch stop layer (ESL) surrounded by Al-free cladding layers, establishing the effectiveness of AlGaN-based ESLs for controlling etch depth in ridge waveguide InGaN/GaN LDs. These results demonstrate the potential for integrating AlGaN ESLs into commercial device designs where accurate control of the etch depth of the ridge waveguide is necessary for stable, kink-free operation at high output powers.

  17. Influence of GaAs surface termination on GaSb/GaAs quantum dot structure and band offsets

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

    Zech, E. S.; Chang, A. S.; Martin, A. J.

    2013-08-19

    We have investigated the influence of GaAs surface termination on the nanoscale structure and band offsets of GaSb/GaAs quantum dots (QDs) grown by molecular-beam epitaxy. Transmission electron microscopy reveals both coherent and semi-coherent clusters, as well as misfit dislocations, independent of surface termination. Cross-sectional scanning tunneling microscopy and spectroscopy reveal clustered GaSb QDs with type I band offsets at the GaSb/GaAs interfaces. We discuss the relative influences of strain and QD clustering on the band offsets at GaSb/GaAs interfaces.

  18. High voltage and high current density vertical GaN power diodes

    DOE PAGES

    Fischer, A. J.; Dickerson, J. R.; Armstrong, A. M.; ...

    2016-01-01

    We report on the realization of a GaN high voltage vertical p-n diode operating at > 3.9 kV breakdown with a specific on-resistance < 0.9 mΩ.cm 2. Diodes achieved a forward current of 1 A for on-wafer, DC measurements, corresponding to a current density > 1.4 kA/cm 2. An effective critical electric field of 3.9 MV/cm was estimated for the devices from analysis of the forward and reverse current-voltage characteristics. Furthermore this suggests that the fundamental limit to the GaN critical electric field is significantly greater than previously believed.

  19. Comparison of alloy disorder scatterings in Ga- and N-polar AlGaN/GaN heterostructures

    NASA Astrophysics Data System (ADS)

    Kang, He; Li, Hui-Jie; Yang, Shao-Yan; Zhang, Wei; Zhu, Ming; Liu, Li; Li, Nan

    2018-01-01

    The two-dimensional electron gas (2DEG) mobilities limited by alloy disorder (AD) scattering in both Ga- and N-polar AlGaN/GaN heterostructures are investigated. It was found that the AD scattering limited electron mobility in N-polar heterostructures is on the order of 103-104 cm2/Vs, which is comparable to the optical phonon scattering at room-temperature. In comparison, the AD scattering in Ga-polar samples is much less important. Moreover, the electron mobility decreases with the 2DEG density in the Ga-polar device but shows a reverse trend in the N-polar counterpart. This is found to be caused by the rather different electric field distributions in Ga- and N-polar AlGaN/GaN heterostructures. In addition, we find that an AlN interlayer can effectively reduce the alloy scattering, mainly due to the large band offset between AlN and GaN. The calculated mobilities have been compared with the experiment results and good agreements are found. We believe that our results are important for the design of AlGaN/GaN heterostructure-based devices, especially the N-polar ones.

  20. 1 CFR 9.2 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Scope. 9.2 Section 9.2 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER THE UNITED STATES... include— (1) Descriptions of the agency's legal authorities, public purposes, programs, and functions; (2...

  1. 1 CFR 9.2 - Scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Scope. 9.2 Section 9.2 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER THE UNITED STATES... include— (1) Descriptions of the agency's legal authorities, public purposes, programs, and functions; (2...

  2. 1 CFR 9.2 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Scope. 9.2 Section 9.2 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER THE UNITED STATES... include— (1) Descriptions of the agency's legal authorities, public purposes, programs, and functions; (2...

  3. Effect of Ga content on luminescence and defects formation processes in Gd3(Ga,Al)5O12:Ce single crystals

    NASA Astrophysics Data System (ADS)

    Grigorjeva, L.; Kamada, K.; Nikl, M.; Yoshikawa, A.; Zazubovich, S.; Zolotarjovs, A.

    2018-01-01

    Luminescence characteristics of Ce3+ - doped Gd3GaxAl5-xO12 single crystals with different Ga contents (x = 1, 2, 3, 4, 5) are studied in the 9-500 K temperature range. The spectra of the afterglow, photoluminescence, radioluminescence, and thermally stimulated luminescence (TSL) of each crystal coincide. The increase of the Ga content results in the high-energy shift of the spectra while the radioluminescence intensity at 9 K remains practically constant up to x = 4. No Ce3+ emission is observed in case of x = 5. The total TSL intensity drastically increases, reaches the maximum value around x = 2-3, and then decreases due to the thermal quenching of the Ce3+ emission. The TSL glow curve maxima are gradually shifting to lower temperatures, and the dependence of the maxima positions and the corresponding trap depths on the Ga content is close to linear. However, the activation energy of the TSL peaks creation under irradiation of the crystals in the 4f - 5d1 absorption band of Ce3+ decreases drastically with the increasing Ga content (especially in the range of x = 1-2), and this dependence is found to be strongly nonlinear. Possible reasons of the nonlinearity are discussed.

  4. Modeling and optimization of a double-well double-barrier GaN/AlGaN/GaN/AlGaN resonant tunneling diode

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Gao, Bo; Gong, Min; Shi, Ruiying

    2017-06-01

    The influence of a GaN layer as a sub-quantum well for an AlGaN/GaN/AlGaN double barrier resonant tunneling diode (RTD) on device performance has been investigated by means of numerical simulation. The introduction of the GaN layer as the sub-quantum well turns the dominant transport mechanism of RTD from the 3D-2D model to the 2D-2D model and increases the energy difference between tunneling energy levels. It can also lower the effective height of the emitter barrier. Consequently, the peak current and peak-to-valley current difference of RTD have been increased. The optimal GaN sub-quantum well parameters are found through analyzing the electrical performance, energy band, and transmission coefficient of RTD with different widths and depths of the GaN sub-quantum well. The most pronounced electrical parameters, a peak current density of 5800 KA/cm2, a peak-to-valley current difference of 1.466 A, and a peak-to-valley current ratio of 6.35, could be achieved by designing RTD with the active region structure of GaN/Al0.2Ga0.8 N/GaN/Al0.2Ga0.8 N (3 nm/1.5 nm/1.5 nm/1.5 nm).

  5. A comparison of meal replacements and medication in weight maintenance after weight loss.

    PubMed

    LeCheminant, James D; Jacobsen, Dennis J; Hall, Matthew A; Donnelly, Joseph E

    2005-10-01

    To compare the use of meal replacements or medication during weight maintenance subsequent to weight loss using a very low-energy diet (VLED) in overweight or obese adults. Participants followed a liquid VLED of 2177 kJ for 12 weeks followed by 4 weeks of re-orientation to solid foods. Participants were randomized at week 16 to receive either meal replacements or Orlistat both combined with a structured meal plan containing an energy value calculated to maintain weight loss. Sixty-four women (age = 49.9 +/- 10 y, weight = 101.6 +/- 17.1 kg, height = 164.9 +/- 6.0 cm, BMI = 36.7 +/- 5.4 kg/m(2)) and 28 men (age = 53.7 +/- 9.6 y, weight = 121.8 +/- 16.0 kg, height = 178.7 +/- 5.6 cm, BMI = 37.8 +/- 4.9 kg/m(2)) completed a 1 year weight management program. Behavioral weight management clinics included topics on lifestyle, physical activity (PA), and nutrition. Participants met for 90 min weekly for 26 weeks, and then biweekly for the remaining 26 weeks. Minutes of PA, fruits and vegetables (FV), and pedometer steps were recorded on a daily basis and reported at each group meeting. Body weight was obtained at each group meeting. During VLED, the MR group decreased body weight by 22.8 +/- 6.1 kg and the Orlistat group decreased body weight by 22.3 +/- 6.1 kg. During weight maintenance, there was no significant group by time interaction for body weight, PA, FV consumption, or pedometer steps. At week 16, the meal replacement group had a body weight of 85.4 +/- 14.3 kg that increased to 88.1 +/- 16.5 kg at 52 weeks (p < 0.05). At week 16, the Orlistat group had a body weight of 85.7 +/- 17.9 kg that increased to 88.5 +/- 20.3 kg at 52 weeks (p < 0.05). Subsequent to weight loss from a VLED, meal replacements and Orlistat treatments were both effective in maintaining weight significantly below baseline levels over a 52 week period of time. Meal replacements may be a viable alternative strategy to medications for weight maintenance.

  6. Comparision between Ga- and N-polarity InGaN solar cells with gradient-In-composition intrinsic layers

    NASA Astrophysics Data System (ADS)

    Lu, Lin; Li, Ming-Chao; Lv, Chen; Gao, Wen-Gen; Jiang, Ming; Xu, Fu-Jun; Chen, Qi-Gong

    2016-10-01

    Performances of Ga- and N-polarity solar cells (SCs) adopting gradient-In-composition intrinsic layer (IL) are compared. It is found the gradient ILs can greatly weaken the negative influence from the polarization effects for the Ga- polarity case, and the highest conversion efficiency (η) of 2.18% can be obtained in the structure with a linear increase of In composition in the IL from bottom to top. This is mainly attributed to the adsorptions of more photons caused by the higher In composition in the IL closer to the p-GaN window layer. In contrast, for the N-polarity case, the SC structure with an InGaN IL adopting fixed In composition prevails over the ones adopting the gradient-In-composition IL, where the highest η of 9.28% can be obtained at x of 0.62. N-polarity SC structures are proven to have greater potential preparations in high-efficient InGaN SCs. Project supported by the National Natural Science Foundation of China (Grant Nos. 61306108, 61172131, and 61271377), the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China (Grant No. 2013693), and the Anhui Polytechnic University Funds for Excellent Young Scientists, China (Grant No. 2014YQQ005).

  7. Synthesis and properties of γ-Ga2O3-Al2O3 solid solutions

    NASA Astrophysics Data System (ADS)

    Afonasenko, T. N.; Leont'eva, N. N.; Talzi, V. P.; Smirnova, N. S.; Savel'eva, G. G.; Shilova, A. V.; Tsyrul'nikov, P. G.

    2017-10-01

    The textural and structural properties of mixed oxides Ga2O3-Al2O3, obtained via impregnating γ-Al2O3 with a solution of Ga(NO3)3 and subsequent heat treatment, are studied. According to the results from X-ray powder diffraction, gallium ions are incorporated into the structure of aluminum oxide to form a solid solution of spinel-type γ-Ga2O3-Al2O3 up to a Ga2O3 content of 50 wt % of the total weight of the sample, accompanied by a reduction in the specific surface area, volume, and average pore diameter. It is concluded that when the Ga2O3 content exceeds 50 wt %, the β-Ga2O3 phase is observed along with γ-Ga2O3-Al2O3 solid solution. 71Ga and 27Al NMR spectroscopy shows that gallium replaces aluminum atoms from the tetrahedral position to the octahedral coordination in the structure of γ-Ga2O3-Al2O3.

  8. Advanced GaAs Process Modeling. Volume 1

    DTIC Science & Technology

    1989-05-01

    COSATI CODES 18 . SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP Gallium Arsenide, MESFET, Process...Background 9 3.2 Model Calculations 10 3.3 Conclusions 17 IV. ION-IMPLANTATION INTO GaAs PROFILE DETERMINATION 18 4.1 Ion Implantation Profile...Determination in GaAs 18 4.1.1. Background 18 4.1.2. Experimental Measurements 20 4.1.3. Results 22 4.1.3.1 Ion-Energy Dependence 22 4.1.3.2. Tilt and Rotation

  9. High-efficiency thin-film GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Stirn, R. J.

    1979-01-01

    GaAs chemical vapor deposition (CVD) growth on single-crystal GaAs substrates was investigated over a temperature range of 600 to 750 C, As/GA mole-ratio range of 3 to 11, and gas molefraction range 5 x 10 to the minus 9th power to 7x 10 to the minus 7th power for H2S doping. GasAs CVD growth on recrystallized Ge films was investigated for a temperature range of 550 to 700 C, an As/GA mole ratio of 5, and for various H2S mole fraction. The highest efficiency cell observed on these films with 2 mm dots was 4.8% (8% when AR-coated). Improvements in fill factor and opencircuit voltage by about 40% each are required in order to obtain efficiencies of 15% or greater.

  10. Nanoscale characterization of GaN/InGaN multiple quantum wells on GaN nanorods by photoluminescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Weijian; Wen, Xiaoming; Latzel, Michael; Yang, Jianfeng; Huang, Shujuan; Shrestha, Santosh; Patterson, Robert; Christiansen, Silke; Conibeer, Gavin

    2017-02-01

    GaN/InGaN multiple quantum wells (MQW) and GaN nanorods have been widely studied as a candidate material for high-performance light emitting diodes. In this study, GaN/InGaN MQW on top of GaN nanorods are characterized in nanoscale using confocal microscopy associated with photoluminescence spectroscopy, including steady-state PL, timeresolved PL and fluorescence lifetime imaging (FLIM). Nanorods are fabricated by etching planar GaN/InGaN MQWs on top of a GaN layer on a c-plane sapphire substrate. Photoluminescence efficiency from the GaN/InGaN nanorods is evidently higher than that of the planar structure, indicating the emission improvement. Time-resolved photoluminescence (TRPL) prove that surface defects on GaN nanorod sidewalls have a strong influence on the luminescence property of the GaN/InGaN MWQs. Such surface defects can be eliminated by proper surface passivation. Moreover, densely packed nanorod array and sparsely standing nanorods have been studied for better understanding the individual property and collective effects from adjacent nanorods. The combination of the optical characterization techniques guides optoelectronic materials and device fabrication.

  11. Microwave power amplifiers based on AlGaN/GaN transistors with a two-dimensional electron gas

    NASA Astrophysics Data System (ADS)

    Vendik, O. G.; Vendik, I. B.; Tural'chuk, P. A.; Parnes, Ya. M.; Parnes, M. D.

    2016-11-01

    A technique for synthesis of microwave power amplifiers based on transistors with a AlGaN/GaN heterojunction is discussed. Special focus is on the development of a technique for synthesis of transformation circuits of the power amplifier to increase efficiency with a retained high output power. The use of independent matching at the harmonic frequencies and fundamental frequency makes it possible to control the attainable efficiency in a wide frequency band along with the total suppression of harmonics beyond the operational band. Microwave power amplifiers for operation at 4 and 9 GHz have been developed and experimentally investigated.

  12. High temperature mass spectrometric studies on Usbnd Ga system: Thermodynamic properties over (U3Ga5 + UGa2) and (UGa2 + UGa3) phase regions

    NASA Astrophysics Data System (ADS)

    Manikandan, P.; Trinadh, V. V.; Bera, Suranjan; Narasimhan, T. S. Lakshmi; Joseph, M.

    2016-07-01

    Vaporisation studies over gallium rich biphasic regions (U3Ga5 + UGa2) and (UGa2 + UGa3) in the Usbnd Ga system were carried out by Knusen effusion mass spectrometry in the temperature ranges of 1208-1366 K and 1133-1338 K, respectively. Ga(g) was the species observed in the mass spectra of the equilibrium vapour over both phase regions. From temperature dependence measurements, pressure-temperature relations were deduced as: log (pGa/Pa) = (-18216 ± 239)/(T/K) + (12.88 ± 0.18) over (U3Ga5 + UGa2) and log (pGa/Pa) = (-16225 ± 124)/(T/K) + (11.78 ± 0.10) over (UGa2 + UGa3). From these data, Gibbs free energy changes for the reactions 3UGa2(s) = U3Ga5(s) + Ga(g) and UGa3(s) = UGa2(s) + Ga(g) were computed and subsequently Gibbs free energies of formation of U3Ga5(s) and UGa3(s) were deduced as ΔfGTo U3Ga5(s) (±5.5) = -352.4 + 0.133 T(K) (kJ mol-1) (1208-1366 K) and ΔfGTo UGa3(s) (±3.8) = -191.9 + 0.082 T(K) (kJ mol-1) (1133-1338 K). The Gibbs free energy of formation of U3Ga5(s) is being reported for the first time.

  13. Effect of varying Ga content in ZnO:GaN solid solution synthesized by solution combustion technique for photocatalytic applications

    NASA Astrophysics Data System (ADS)

    Menon, Sumithra Sivadas; Janani, R.; Baskar, K.; Gupta, Bhavana; Singh, Shubra

    2017-05-01

    ZnO:GaN (oxy)nitride solid solution has been established as the most efficient non-oxide photocatalyst for water splitting under visible irradiation with one step photoexcitation and also boasts a band gap tunability from 2.8 eV to 2.5 eV[1]. The solid solution of GaN in ZnO is formed by the intersubstitution of few of Zn/O ions by Ga/N ions, and this results in the introduction of new defect levels above the valence band which narrows the effective band gap enabling activity under visible region of spectra. In this work, we report the synthesis of ZnO:GaN solid solution by a solution combustion technique where metal nitrates and urea are used as precursors. The Zn/Ga ratio was varied from 16 to 1 in the precursors. The as synthesized samples were characterized as phase pure by X-ray diffraction, where the wurtzite structure was retained up to Zn/Ga ratio of 5. The Diffuse reflectance spectroscopy studies revealed that as the Ga content in the solid solution increases there is a reduction in band gap, from 2.9 eV to 2.4 eV. The reduced band gap of the samples facilitates its photocatalytic activity under visible region of the spectra as evaluated by photoelectrochemical measurements.

  14. Evaluation of AlGaN/GaN high electron mobility transistors grown on ZrTi buffer layers with sapphire substrates

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

    Ren, Fan; Pearton, Stephen J.; Ahn, Shihyun

    Here, AlGaN/GaN high electron mobility transistors (HEMTs) have been grown on sapphire substrates, using ZrTi buffer layers to provide in-plane lattice-matching to hexagonal GaN. X-ray diffraction (XRD) as well as cross-section transmission electron microscopy (TEM) were used to assess the quality of the HEMT structure. The XRD 2θ scans showed full-width-at-half-maximum values of 0.16°, 0.07°, and 0.08° for ZrTi alloy, GaN buffer layer, and the entire HEMT structure, respectively. TEM studies of the GaN buffer layer and the AlN/ZrTi/AlN stack showed the importance of growing thin AlN buffer layers on the ZrTi layer prior to growth of the GaN buffermore » layer. The density of threading dislocations in the GaN channel layer of the HEMT structure was estimated to be in the 10 8 cm –2 range. The HEMT device exhibited a saturation drain current density of 820 mA/mm, and the channel of the fabricated HEMTs could be well modulated. A cutoff frequency (f T) of 8.9 GHz and a maximum frequency of oscillation (f max) of 17.3 GHz were achieved for HEMTs with gate dimensions of 1 × 200 μm.« less

  15. Evaluation of AlGaN/GaN high electron mobility transistors grown on ZrTi buffer layers with sapphire substrates

    DOE PAGES

    Ren, Fan; Pearton, Stephen J.; Ahn, Shihyun; ...

    2016-09-21

    Here, AlGaN/GaN high electron mobility transistors (HEMTs) have been grown on sapphire substrates, using ZrTi buffer layers to provide in-plane lattice-matching to hexagonal GaN. X-ray diffraction (XRD) as well as cross-section transmission electron microscopy (TEM) were used to assess the quality of the HEMT structure. The XRD 2θ scans showed full-width-at-half-maximum values of 0.16°, 0.07°, and 0.08° for ZrTi alloy, GaN buffer layer, and the entire HEMT structure, respectively. TEM studies of the GaN buffer layer and the AlN/ZrTi/AlN stack showed the importance of growing thin AlN buffer layers on the ZrTi layer prior to growth of the GaN buffermore » layer. The density of threading dislocations in the GaN channel layer of the HEMT structure was estimated to be in the 10 8 cm –2 range. The HEMT device exhibited a saturation drain current density of 820 mA/mm, and the channel of the fabricated HEMTs could be well modulated. A cutoff frequency (f T) of 8.9 GHz and a maximum frequency of oscillation (f max) of 17.3 GHz were achieved for HEMTs with gate dimensions of 1 × 200 μm.« less

  16. Polarization compensation at low p-GaN doping density in InGaN/GaN p-i-n solar cells: Effect of InGaN interlayers

    NASA Astrophysics Data System (ADS)

    Saini, Basant; Adhikari, Sonachand; Pal, Suchandan; Kapoor, Avinsahi

    2017-07-01

    The effectiveness of polarization matching layer (PML) between i-InGaN/p-GaN is studied numerically for Ga-face InGaN/GaN p-i-n solar cell at low p-GaN doping (∼5e17 cm-3). The simulations are performed for four InxGa1-xN/GaN heterostructures (x = 10%, 15%, 20% and 25%), thus investigating the impact of PML for low as well as high indium containing absorber regions. Use of PML presents a suitable alternative to counter the effects of polarization-induced electric fields arising at low p-GaN doping density especially for absorber regions with high indium (>10%). It is seen that it not only mitigates the negative effects of polarization-induced electric fields but also reduces the high potential barriers existing at i-InGaN/p-GaN heterojunction. The improvement in photovoltaic properties of the heterostructures even at low p-GaN doping validates this claim.

  17. Effect of graded InGaN drain region and 'In' fraction in InGaN channel on performances of InGaN tunnel field-effect transistor

    NASA Astrophysics Data System (ADS)

    Duan, Xiaoling; Zhang, Jincheng; Wang, Shulong; Quan, Rudai; Hao, Yue

    2017-12-01

    An InGaN-based graded drain region tunnel field-effect transistor (GD-TFET) is proposed to suppress the ambipolar behavior. The simulation results with the trade-off between on-state current (Ion) and ambipolar current (Iambipolar) show decreased Iambipolar (1.9 × 10-14 A/μm) in comparison with that of conventional TFETs (2.0 × 10-8 A/μm). Furthermore, GD-TFET with high 'In' fraction InxGa1-xN source-side channel (SC- GD-TFET) is explored and exhibits 5.3 times Ion improvement and 60% average subthreshold swing (SSavg) reduction in comparison with GD-TFET by adjusting 'In' fraction in the InxGa1-xN source-side channel. The improvement is attributed to the confinement of BTBT in the source-side channel by the heterojunction. And then, the optimum value for source-side channel length (Lsc) is researched by DC performances results, which shows it falls into the range between Lsc = 10 nm and 20 nm.

  18. Improved performance in vertical GaN Schottky diode assisted by AlGaN tunneling barrier

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

    Cao, Y.; Chu, R.; Li, R.

    2016-03-14

    In a vertical GaN Schottky barrier diode, the free electron concentration n in the 6-μm-thick drift layer was found to greatly impact the diode reverse leakage current, which increased from 2.1 × 10{sup −7} A to 3.9 × 10{sup −4} A as n increased from 7.5 × 10{sup 14 }cm{sup −3} to 6.3 × 10{sup 15 }cm{sup −3} at a reverse bias of 100 V. By capping the drift layer with an ultrathin 5-nm graded AlGaN layer, reverse leakage was reduced by more than three orders of magnitude with the same n in the drift layer. We attribute this to the increased Schottky barrier height with the AlGaN at the surface. Meanwhile, themore » polarization field within the graded AlGaN effectively shortened the depletion depth, which led to the formation of tunneling current at a relatively small forward bias. The turn-on voltage in the vertical Schottky diodes was reduced from 0.77 V to 0.67 V—an advantage in reducing conduction loss in power switching applications.« less

  19. Zero-resistance states induced by electromagnetic-wave excitation in GaAs/AlGaAs heterostructures.

    PubMed

    Mani, Ramesh G; Smet, Jürgen H; von Klitzing, Klaus; Narayanamurti, Venkatesh; Johnson, William B; Umansky, Vladimir

    2002-12-12

    The observation of vanishing electrical resistance in condensed matter has led to the discovery of new phenomena such as, for example, superconductivity, where a zero-resistance state can be detected in a metal below a transition temperature T(c) (ref. 1). More recently, quantum Hall effects were discovered from investigations of zero-resistance states at low temperatures and high magnetic fields in two-dimensional electron systems (2DESs). In quantum Hall systems and superconductors, zero-resistance states often coincide with the appearance of a gap in the energy spectrum. Here we report the observation of zero-resistance states and energy gaps in a surprising setting: ultrahigh-mobility GaAs/AlGaAs heterostructures that contain a 2DES exhibit vanishing diagonal resistance without Hall resistance quantization at low temperatures and low magnetic fields when the specimen is subjected to electromagnetic wave excitation. Zero-resistance-states occur about magnetic fields B = 4/5 Bf and B = 4/9 Bf, where Bf = 2pifm*/e,m* is the electron mass, e is the electron charge, and f is the electromagnetic-wave frequency. Activated transport measurements on the resistance minima also indicate an energy gap at the Fermi level. The results suggest an unexpected radiation-induced, electronic-state-transition in the GaAs/AlGaAs 2DES.

  20. Labeling of monoclonal antibodies with a 67Ga-phenolic aminocarboxylic acid chelate. Part II. Comparison of immunoreactivity and biodistribution of monoclonal antibodies labeled with the 67Ga-chelate or with 131I.

    PubMed

    Matzku, S; Schuhmacher, J; Kirchgessner, H; Brüggen, J

    1986-01-01

    Coupling of the 67Ga-P-EDDHA chelate via carbodiimide to the anti-melanoma monoclonal antibody (Mab) M.2.9.4 resulted in a low degree of oligomerization, but a considerable degree of intra-molecular (inter-chain) cross-linking. However, this did not impair immunoreactivity, nor did the half-life in vivo differ substantially from that of 131I-M.2.9.4. Biodistribution analysis in normal mice showed Ga:I ratios near 1 in the blood and other tissues not involved in degradation and label excretion. In tissues of the reticulo-endothelial system (RES) and the kidneys, Ga:I ratios up to 2.51 were reached within 4 days of administration. In antigen-positive MeWo tumor tissue, retention of 67Ga also excreted that of 131I, so that tumor; organ ratios (except tumor:liver) were superior for the 67Ga-labeled MAb. It is concluded that the method of coupling pre-established 67Ga-P-EDDHA chelate to antibody results in a functionally intact tracer molecule, whose persistence in vivo is not significantly impaired. The major difference to I-labeled MAbs may be a prolonged retention of Ga in tissues (cells) physiologically involved in antibody catabolism.

  1. GaSbBi/GaSb quantum well laser diodes

    NASA Astrophysics Data System (ADS)

    Delorme, O.; Cerutti, L.; Luna, E.; Narcy, G.; Trampert, A.; Tournié, E.; Rodriguez, J.-B.

    2017-05-01

    We report on the structural and optical properties of GaSbBi single layers and GaSbBi/GaSb quantum well heterostructures grown by molecular beam epitaxy on GaSb substrates. Excellent crystal quality and room-temperature photoluminescence are achieved in both cases. We demonstrate laser operation from laser diodes with an active zone composed of three GaSb0.885Bi0.115/GaSb quantum wells. These devices exhibit continuous-wave lasing at 2.5 μm at 80 K, and lasing under pulsed operation at room-temperature near 2.7 μm.

  2. Alzheimer's disease and the law: positive and negative consequences of structural stigma and labeling in the legal system.

    PubMed

    Werner, Perla; Doron, Israel Issi

    2017-11-01

    To explore the meaning and consequences of labeling on structural stigma in the context of Alzheimer's disease (AD) in the legal system. This qualitative study was made up of three focus groups including social workers and lawyers (n = 26). Participants were asked to report their experience in circumstances in which persons with AD and their family members engage with the legal system. Thematic analysis using the constant comparative method was used. The discussions in the focus groups raised two overall themes. (1) The significance of the medical diagnostic labeling of AD in the legal system and (2) the consequences of labeling of AD within the legal system. This last theme included four sub-themes: (a) negative consequences of labeling; (b) reasons associated with negative consequences of labeling; (c) positive consequences of labeling; and (d) reasons associated with positive consequences of labeling. Findings of the study provide a first foundation for future research on the meaning and consequences of labeling in legal cases involving persons with AD. They suggest that increasing judges' knowledge about AD and reforming the existing 'status-based' legal capacity legislation might benefit by limiting the legal weight given today to the medical diagnosis.

  3. Progress toward the development of dual junction GaAs/Ge solar cells

    NASA Technical Reports Server (NTRS)

    Lillington, D. R.; Krut, D. D.; Cavicchi, B. T.; Ralph, E.; Chung, M.

    1991-01-01

    Large area GaAs/Ge cells offer substantial promise for increasing the power output from existing silicon solar array designs and for providing an enabled technology for missions hitherto impossible using silicon. Single junction GaAs/Ge cells offer substantial advantages in both size, weight, and cost compared to GaAs cells but the efficiency is limited to approximately 19.2 to 20 percent AMO. The thermal absorptance of GaAs/Ge cells is also worse than GaAs/GaAs cells (0.88 vs 0.81 typ.) due to the absorption in the Ge substrate. On the other hand dual junction GaAs/Ge cells offer efficiencies up to ultimately 24 percent AMO in sizes up to 8 x 8 cm but there are still technological issues remaining to achieve current matching in the GaAs and Ge cells. This can be achieved through tuned antireflection (AR) coatings, improved quality of the GaAs growth, improved quality Ge wafers and the use of a Back Surface Field (BSF)/Back Surface Reflector (BSR) in the Ge cell. Although the temperature coefficients of efficiency and voltage are higher for dual junction GaAs/Ge cells, it has been shown elsewhere that for typical 28 C cell efficiencies of 22 percent (dual junction) vs 18.5 percent (single junction) there is a positive power tradeoff up to temperatures as high as 120 C. Due to the potential ease of fabrication of GaAs/Ge dual junction cells there is likely to be only a small cost differential compared to single junction cells.

  4. Heterosis and direct effects for Charolais-sired calf weight and growth, cow weight and weight change, and ratios of cow and calf weights and weight changes across warm season lactation in Romosinuano, Angus, and F cows in Arkansas.

    PubMed

    Riley, D G; Burke, J M; Chase, C C; Coleman, S W

    2016-01-01

    The use of Brahman in cow-calf production offers some adaptation to the harsh characteristics of endophyte-infected tall fescue. Criollo breeds, such as the Romosinuano, may have similar adaptation. The objectives were to estimate genetic effects in Romosinuano, Angus, and crossbred cows for their weights, weights of their calves, and ratios (calf weight:cow weight and cow weight change:calf weight gain) across lactation and to assess the influence of forage on traits and estimates. Cows ( = 91) were bred to Charolais bulls after their second parity. Calves ( = 214) were born from 2006 to 2009. Cows and calves were weighed in early (April and June), mid- (July), and late lactation (August and October). Animal was a random effect in analyses of calf data; sire was random in analyses of cow records and ratios. Fixed effects investigated included calf age, calf sex, cow age-year combinations, sire breed of cow, dam breed of cow, and interactions. Subsequent analyses evaluated the effect of forage grazed: endophyte-free or endophyte-infected tall fescue. Estimates of maternal heterosis for calf weight ranged from 9.3 ± 4.3 to 15.4 ± 5.7 kg from mid-lactation through weaning ( < 0.05). Romosinuano direct effects (of the cow) were -6.8 ± 3.0 and -8.9 ± 4.2 kg for weights recorded in April and June. Calf weights and weight gains from birth were greater ( < 0.05) for calves of cows grazing endophyte-free tall fescue except in mid-summer. Cow weight change from April to each time was negative for Angus cows and lower ( < 0.05) than other groups. Cows grazing endophyte-free tall fescue were heavier ( < 0.05) at all times but had more weight loss in late lactation. Angus cows had the lowest ( < 0.05) ratios (negative) of cow weight change:calf weight gain, indicating an energy-deficit condition. Cows grazing endophyte-free tall fescue had more negative ( < 0.05) values for this trait but not in early lactation ( < 0.05). Estimates of heterosis ranged from 12.8 ± 9.5 to

  5. High-power flexible AlGaN/GaN heterostructure field-effect transistors with suppression of negative differential conductance

    NASA Astrophysics Data System (ADS)

    Oh, Seung Kyu; Cho, Moon Uk; Dallas, James; Jang, Taehoon; Lee, Dong Gyu; Pouladi, Sara; Chen, Jie; Wang, Weijie; Shervin, Shahab; Kim, Hyunsoo; Shin, Seungha; Choi, Sukwon; Kwak, Joon Seop; Ryou, Jae-Hyun

    2017-09-01

    We investigate thermo-electronic behaviors of flexible AlGaN/GaN heterostructure field-effect transistors (HFETs) for high-power operation of the devices using Raman thermometry, infrared imaging, and current-voltage characteristics. A large negative differential conductance observed in HFETs on polymeric flexible substrates is confirmed to originate from the decreasing mobility of the two-dimensional electron gas channel caused by the self-heating effect. We develop high-power transistors by suppressing the negative differential conductance in the flexible HFETs using chemical lift-off and modified Ti/Au/In metal bonding processes with copper (Cu) tapes for high thermal conductivity and low thermal interfacial resistance in the flexible hybrid structures. Among different flexible HFETs, the ID of the HFETs on Cu with Ni/Au/In structures decreases only by 11.3% with increasing drain bias from the peak current to the current at VDS = 20 V, which is close to that of the HFETs on Si (9.6%), solving the problem of previous flexible AlGaN/GaN transistors.

  6. 7 CFR 1400.9 - Appeals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE GENERAL REGULATIONS AND POLICIES PAYMENT LIMITATION AND PAYMENT ELIGIBILITY FOR 2009 AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS General Provisions § 1400.9 Appeals. (a) A person or legal entity...

  7. Legal Status and Wage Disparities for Mexican Immigrants

    PubMed Central

    Hall, Matthew; Greenman, Emily; Farkas, George

    2014-01-01

    This paper employs a unique method of imputing the legal status of Mexican immigrants in the 1996-1999 and 2001-2003 panels of the Survey of Income and Program Participation to provide new evidence of the role of legal authorization in the U.S. on workers’ wages. Using growth curve techniques, we estimate wage trajectories for four groups: documented Mexican immigrants, undocumented Mexican immigrants, U.S-born Mexican Americans, and native non-Latino whites. Our estimates reveal a 17 percent wage disparity between documented and undocumented Mexican immigrant men, and a 9 percent documented-undocumented wage disparity for Mexican immigrant women. We also find that in comparison to authorized Mexicans, undocumented Mexican immigrants have lower returns to human capital and slower wage growth. PMID:25414526

  8. Legal Status and Wage Disparities for Mexican Immigrants.

    PubMed

    Hall, Matthew; Greenman, Emily; Farkas, George

    2010-12-01

    This paper employs a unique method of imputing the legal status of Mexican immigrants in the 1996-1999 and 2001-2003 panels of the Survey of Income and Program Participation to provide new evidence of the role of legal authorization in the U.S. on workers' wages. Using growth curve techniques, we estimate wage trajectories for four groups: documented Mexican immigrants, undocumented Mexican immigrants, U.S-born Mexican Americans, and native non-Latino whites. Our estimates reveal a 17 percent wage disparity between documented and undocumented Mexican immigrant men, and a 9 percent documented-undocumented wage disparity for Mexican immigrant women. We also find that in comparison to authorized Mexicans, undocumented Mexican immigrants have lower returns to human capital and slower wage growth.

  9. Insertion of GaAs MMICs into EW systems

    NASA Astrophysics Data System (ADS)

    Schineller, E. R.; Pospishil, A.; Grzyb, J.

    1989-09-01

    Development activities on a microwave/mm-wave monolithic IC (MIMIC) program are described, as well as the methodology for inserting these GaAs IC chips into several EW systems. The generic EW chip set developed on the MIMIC program consists of 23 broadband chip types, including amplifiers, oscillators, mixers, switches, variable attenuators, power dividers, and power combiners. These chips are being designed for fabrication using the multifunction self-aligned gate process. The benefits from GaAs IC insertion are quantified by a comparison of hardware units fabricated with existing MIC and digital ECL technology and the same units manufactured with monolithic technology. It is found that major improvements in cost, reliability, size, weight, and performance can be realized. Examples illustrating the methodology for technology insertion are presented.

  10. Self-organization of palladium nanoislands on GaN and AlxGa1-xN/GaN heterostructures

    NASA Astrophysics Data System (ADS)

    Stafiniak, Andrzej; Szymański, Tomasz; Paszkiewicz, Regina

    2017-12-01

    We report on systematic study on the dewetting process of thin Pd layer and self-organized Pd nano-islands on SiO2, GaN and AlxGa1-xN/GaN heterostructures with various Al content. The influence of factors such as the thickness of metal layer, type of top layer of AlGaN/GaN heterostructures, temperature and time of annealing process on the dimensions, shapes and density of Pd islands was analyzed. Comparing the behavior of self-organization of Pd islands on Al0.25Ga0.75N/GaN and SiO2 we can conclude that solid-state dewetting process on SiO2 occures much faster than on Al0.25Ga0.75N. For substrates with SiO2 this process requires less energy and can arise for thicker layer. On the Al0.25Ga0.75N surface the islands take more crystalline shape which is probably due to surface reconstruction of Pd-Ga alloy thin layer on interface. For thin metal layer the coalescence of islands into larger islands similar to Ostwald ripening mechanism was observed. Greater surface roughness of AlxGa1-xN/GaN heterostructures with higher Al content causes an increase of surface density of islands and the reduction of their sizes which improves the roundness. In case of GaN and AlxGa1-xN layers with Al content lower than 20%, the surface degradation caused by annealing process was observed. Probably, this is due to the decomposition of layers with gallium droplet formation on catalytic metal islands.

  11. 8- to 9-μm and 14- to 15-μm two-color 640x486 GaAs/AlGaAs quantum well infrared photodetector (QWIP) focal plane array camera

    NASA Astrophysics Data System (ADS)

    Gunapala, Sarath D.; Bandara, Sumith V.; Singh, Anjali; Liu, John K.; Rafol, S. B.; Luong, Edward M.; Mumolo, Jason M.; Tran, N. Q.; Vincent, John D.; Shott, C. A.; Long, James F.; LeVan, Paul D.

    1999-07-01

    An optimized long-wavelength two-color quantum well IR photodetector (QWIP) device structure has been designed. This device structure was grown on a three-inch semi- insulating GaAs substrate by molecule beam epitaxy (MBE). This wafer was processed into several 640 X 486 format monolithically integrated 8-9 and 14-15 micrometers two-color QWIP focal plane arrays (FPAs). These FPAs were then hybridized to 640 X 486 silicon CMOS readout multiplexers. A thinned FPA hybrid was integrated into a liquid helium cooled dewar to perform electrical and optical characterization and to demonstrate simultaneous two-color imagery. The 8-9 micrometers detectors in the FPA have shown background limited performance (BLIP) at 70 K operating temperature, at 300 K background with f/2 cold stop. The 14-15 micrometers detectors of the FPA have reached BLIP at 40 K operating temperature at the same background conditions. In this paper we discuss the performance of this long-wavelength dualband QWIP FPA in quantum efficiency, detectivity, noise equivalent temperature difference, uniformity, and operability.

  12. Dissection of Arabidopsis NCED9 promoter regulatory regions reveals a role for ABA synthesized in embryos in the regulation of GA-dependent seed germination.

    PubMed

    Seo, Mitsunori; Kanno, Yuri; Frey, Anne; North, Helen M; Marion-Poll, Annie

    2016-05-01

    Nine-cis-epoxycarotenoid dioxygenase (NCED) catalyzes the key step of abscisic acid (ABA) biosynthesis. There are five genes encoding NCED in Arabidopsis, which differentially regulate ABA biosynthesis in a spatiotemporal manner in response to endogenous and environmental stimuli. Previous studies have shown that NCED9 is expressed in testa and embryos during seed development. In the present study, we have identified promoter regions required for the expression of NCED9 in testa and embryos, respectively. Electrophoretic mobility shift assays (EMSA) and yeast one-hybrid (Y1H) assays showed that several homeodomain-leucine zipper (HD-Zip) proteins, namely ATHBs, bound to the sequence required for expression of NCED9 in testa, suggesting that they redundantly regulate NCED9 expression. By expressing the NCED9 gene under the control of a deleted NCED9 promoter in an nced9 mutant expression was limited to embryos. Transformants were complemented for the paclobutrazol resistant germination phenotype of the mutant, suggesting that the ABA synthesis mediated by NCED9 in embryos plays an important role in the regulation of gibberellin (GA)-dependent seed germination. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Legal Issues in Higher Education.

    ERIC Educational Resources Information Center

    Branton, Wiley A.

    1984-01-01

    Legal problems that colleges and universities might avoid are identified. Colleges are being sued over a broad range of legal issues and are expending money for legal and court fees, settlements, and judgments. Legal problems include right of admission to particular colleges, the right to stay in school, questions of faculty promotion and tenure,…

  14. Metal-interconnection-free integration of InGaN/GaN light emitting diodes with AlGaN/GaN high electron mobility transistors

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

    Liu, Chao; Cai, Yuefei; Liu, Zhaojun

    2015-05-04

    We report a metal-interconnection-free integration scheme for InGaN/GaN light emitting diodes (LEDs) and AlGaN/GaN high electron mobility transistors (HEMTs) by combining selective epi removal (SER) and selective epitaxial growth (SEG) techniques. SER of HEMT epi was carried out first to expose the bottom unintentionally doped GaN buffer and the sidewall GaN channel. A LED structure was regrown in the SER region with the bottom n-type GaN layer (n-electrode of the LED) connected to the HEMTs laterally, enabling monolithic integration of the HEMTs and LEDs (HEMT-LED) without metal-interconnection. In addition to saving substrate real estate, minimal interface resistance between the regrownmore » n-type GaN and the HEMT channel is a significant improvement over metal-interconnection. Furthermore, excellent off-state leakage characteristics of the driving transistor can also be guaranteed in such an integration scheme.« less

  15. Optimization of GaAs Nanowire Pin Junction Array Solar Cells by Using AlGaAs/GaAs Heterojunctions

    NASA Astrophysics Data System (ADS)

    Wu, Yao; Yan, Xin; Wei, Wei; Zhang, Jinnan; Zhang, Xia; Ren, Xiaomin

    2018-04-01

    We optimized the performance of GaAs nanowire pin junction array solar cells by introducing AlGaAs/GaAs heterejunctions. AlGaAs is used for the p type top segment for axial junctions and the p type outer shell for radial junctions. The AlGaAs not only serves as passivation layers for GaAs nanowires but also confines the optical generation in the active regions, reducing the recombination loss in heavily doped regions and the minority carrier recombination at the top contact. The results show that the conversion efficiency of GaAs nanowires can be greatly enhanced by using AlGaAs for the p segment instead of GaAs. A maximum efficiency enhancement of 8.42% has been achieved in this study. And for axial nanowire, by using AlGaAs for the top p segment, a relatively long top segment can be employed without degenerating device performance, which could facilitate the fabrication and contacting of nanowire array solar cells. While for radial nanowires, AlGaAs/GaAs nanowires show better tolerance to p-shell thickness and surface condition.

  16. Optimization of GaAs Nanowire Pin Junction Array Solar Cells by Using AlGaAs/GaAs Heterojunctions.

    PubMed

    Wu, Yao; Yan, Xin; Wei, Wei; Zhang, Jinnan; Zhang, Xia; Ren, Xiaomin

    2018-04-25

    We optimized the performance of GaAs nanowire pin junction array solar cells by introducing AlGaAs/GaAs heterejunctions. AlGaAs is used for the p type top segment for axial junctions and the p type outer shell for radial junctions. The AlGaAs not only serves as passivation layers for GaAs nanowires but also confines the optical generation in the active regions, reducing the recombination loss in heavily doped regions and the minority carrier recombination at the top contact. The results show that the conversion efficiency of GaAs nanowires can be greatly enhanced by using AlGaAs for the p segment instead of GaAs. A maximum efficiency enhancement of 8.42% has been achieved in this study. And for axial nanowire, by using AlGaAs for the top p segment, a relatively long top segment can be employed without degenerating device performance, which could facilitate the fabrication and contacting of nanowire array solar cells. While for radial nanowires, AlGaAs/GaAs nanowires show better tolerance to p-shell thickness and surface condition.

  17. 20 CFR 404.733 - Evidence you are the legally adopting parent or legally adopted child.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Evidence you are the legally adopting parent or legally adopted child. 404.733 Section 404.733 Employees' Benefits SOCIAL SECURITY ADMINISTRATION... Benefits § 404.733 Evidence you are the legally adopting parent or legally adopted child. If you are the...

  18. Spin injection in epitaxial MnGa(111)/GaN(0001) heterostructures

    NASA Astrophysics Data System (ADS)

    Zube, Christian; Malindretos, Joerg; Watschke, Lars; Zamani, Reza R.; Disterheft, David; Ulbrich, Rainer G.; Rizzi, Angela; Iza, Michael; Keller, Stacia; DenBaars, Steven P.

    2018-01-01

    Ferromagnetic MnGa(111) layers were grown on GaN(0001) by molecular beam epitaxy. MnGa/GaN Schottky diodes with a doping level of around n = 7 × 1018 cm-3 were fabricated to achieve single step tunneling across the metal/semiconductor junction. Below the GaN layer, a thin InGaN quantum well served as optical spin detector ("spin-LED"). For electron spin injection from MnGa into GaN and subsequent spin transport through a 45 nm (70 nm) thick GaN layer, we observe a circular polarization of 0.3% (0.2%) in the electroluminescence at 80 K. Interface mixing, spin polarization losses during electrical transport in the GaN layer, and spin relaxation in the InGaN quantum well are discussed in relation with the low value of the optically detected spin polarization.

  19. The Principal's Legal Handbook.

    ERIC Educational Resources Information Center

    Camp, William E., Ed.; And Others

    The principal is faced with myriad legal issues on a daily basis, making it imperative that he or she keep abreast with developing legal issues. The first of four sections, "Students and the Law," surveys federal statutes and landmark Supreme Court decisions pertaining to the rights of students. It addresses legal issues regarding search and…

  20. Meningiomas: A Comparative Study of 68Ga-DOTATOC, 68Ga-DOTANOC and 68Ga-DOTATATE for Molecular Imaging in Mice

    PubMed Central

    Soto-Montenegro, María Luisa; Peña-Zalbidea, Santiago; Mateos-Pérez, Jose María; Oteo, Marta; Romero, Eduardo; Morcillo, Miguel Ángel; Desco, Manuel

    2014-01-01

    Purpose The goal of this study was to compare the tumor uptake kinetics and diagnostic value of three 68Ga-DOTA-labeled somatostatin analogues (68Ga-DOTATOC, 68Ga-DOTANOC, and 68Ga-DOTATATE) using PET/CT in a murine model with subcutaneous meningioma xenografts. Methods The experiment was performed with 16 male NUDE NU/NU mice bearing xenografts of a human meningioma cell line (CH-157MN). 68Ga-DOTATOC, 68Ga-DOTANOC, and 68Ga-DOTATATE were produced in a FASTLab automated platform. Imaging was performed on an Argus small-animal PET/CT scanner. The SUVmax of the liver and muscle, and the tumor-to-liver (T/L) and tumor-to-muscle (T/M) SUV ratios were computed. Kinetic analysis was performed using Logan graphical analysis for a two-tissue reversible compartmental model, and the volume of distribution (Vt) was determined. Results Hepatic SUVmax and Vt were significantly higher with 68Ga-DOTANOC than with 68Ga-DOTATOC and 68Ga-DOTATATE. No significant differences between tracers were found for SUVmax in tumor or muscle. No differences were found in the T/L SUV ratio between 68Ga-DOTATATE and 68Ga-DOTATOC, both of which had a higher fraction than 68Ga-DOTANOC. The T/M SUV ratio was significantly higher with 68Ga-DOTATATE than with 68Ga-DOTATOC and 68Ga-DOTANOC. The Vt for tumor was higher with 68Ga-DOTATATE than with 68Ga-DOTANOC and relatively similar to that of 68Ga-DOTATOC. Conclusions This study demonstrates, for the first time, the ability of the three radiolabeled somatostatin analogues tested to image a human meningioma cell line. Although Vt was relatively similar with 68Ga-DOTATATE and 68Ga-DOTATOC, uptake was higher with 68Ga-DOTATATE in the tumor than with 68Ga-DOTANOC and 68Ga-DOTATOC, suggesting a higher diagnostic value of 68Ga-DOTATATE for detecting meningiomas. PMID:25369268

  1. Theoretical and experimental studies of electric field distribution in N-polar GaN/AlGaN/GaN heterostructures

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

    Gladysiewicz, M., E-mail: marta.gladysiewicz@pwr.edu.pl; Janicki, L.; Kudrawiec, R.

    2015-12-28

    Electric field distribution in N-polar GaN(channel)/AlGaN/GaN(buffer) heterostructures was studied theoretically by solving Schrodinger and Poisson equations in a self-consistent manner for various boundary conditions and comparing results of these calculations with experimental data, i.e., measurements of electric field in GaN(channel) and AlGaN layers by electromodulation spectroscopy. A very good agreement between theoretical calculations and experimental data has been found for the Fermi-level located at ∼0.3 eV below the conduction band at N-polar GaN surface. With this surface boundary condition, the electric field distribution and two dimensional electron gas concentration are determined for GaN(channel)/AlGaN/GaN(buffer) heterostructures of various thicknesses of GaN(channel) and AlGaNmore » layers.« less

  2. [Legal framework of data protection : current requirements in Germany and requirements in planned European Union regulations].

    PubMed

    Schütze, B

    2013-05-01

    The federal system in Germany necessitates that in addition to federal laws, country and church-specific legislations must also be considered during the evaluation of relevant legal stipulations concerning data protection. Furthermore, there are also special legal regulations for hospitals in almost every federal state which are governed by the principle of subsidiarity: special legal regulations are to be preferentially used, so that findings from one federal state are difficult to transfer to another federal state.Patient data may only be used and processed without legal regulations with informed consent of the patient. The use of patient data for purposes of quality assurance, research and further education of students and doctors is possible under the present laws according to a positive weighting of interests. Patient data can also be exchanged via online services for the purposes of patient care; however, informed consent of the patient for medical online services is almost always unavoidable.

  3. Role of AlGaN/GaN interface traps on negative threshold voltage shift in AlGaN/GaN HEMT

    NASA Astrophysics Data System (ADS)

    Malik, Amit; Sharma, Chandan; Laishram, Robert; Bag, Rajesh Kumar; Rawal, Dipendra Singh; Vinayak, Seema; Sharma, Rajesh Kumar

    2018-04-01

    This article reports negative shift in the threshold-voltage in AlGaN/GaN high electron mobility transistor (HEMT) with application of reverse gate bias stress. The device is biased in strong pinch-off and low drain to source voltage condition for a fixed time duration (reverse gate bias stress), followed by measurement of transfer characteristics. Negative threshold voltage shift after application of reverse gate bias stress indicates the presence of more carriers in channel as compared to the unstressed condition. We propose the presence of AlGaN/GaN interface states to be the reason of negative threshold voltage shift, and developed a process to electrically characterize AlGaN/GaN interface states. We verified the results with Technology Computer Aided Design (TCAD) ATLAS simulation and got a good match with experimental measurements.

  4. Ideals versus reality: Are weight ideals associated with weight change in the population?

    PubMed

    Kärkkäinen, Ulla; Mustelin, Linda; Raevuori, Anu; Kaprio, Jaakko; Keski-Rahkonen, Anna

    2016-04-01

    To quantify weight ideals of young adults and to examine whether the discrepancy between actual and ideal weight is associated with 10-year body mass index (BMI) change in the population. This study comprised 4,964 adults from the prospective population-based FinnTwin16 study. They reported their actual and ideal body weight at age 24 (range 22-27) and 10 years later (attrition 24.6%). The correlates of discrepancy between actual and ideal body weight and the impact on subsequent BMI change were examined. The discrepancy between actual and ideal weight at 24 years was on average 3.9 kg (1.4 kg/m(2) ) among women and 1.2 kg (0.4 kg/m(2) ) among men. On average, participants gained weight during follow-up irrespective of baseline ideal weight: women ¯x = +4.8 kg (1.7 kg/m(2) , 95% CI 1.6-1.9 kg/m(2) ), men ¯x = +6.3 kg (2.0 kg/m(2) , 95% CI 1.8-2.1 kg/m(2) ). Weight ideals at 24 years were not correlated with 10-year weight change. At 34 years, just 13.2% of women and 18.9% of men were at or below the weight they had specified as their ideal weight at 24 years. Women and men adjusted their ideal weight upward over time. Irrespective of ideal weight at baseline, weight gain was nearly universal. Weight ideals were shifted upward over time. © 2016 The Obesity Society.

  5. Metalorganic chemical vapor deposition growth of high-mobility AlGaN/AlN/GaN heterostructures on GaN templates and native GaN substrates

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

    Chen, Jr-Tai, E-mail: jrche@ifm.liu.se; Hsu, Chih-Wei; Forsberg, Urban

    2015-02-28

    Severe surface decomposition of semi-insulating (SI) GaN templates occurred in high-temperature H{sub 2} atmosphere prior to epitaxial growth in a metalorganic chemical vapor deposition system. A two-step heating process with a surface stabilization technique was developed to preserve the GaN template surface. Utilizing the optimized heating process, a high two-dimensional electron gas mobility ∼2000 cm{sup 2}/V·s was obtained in a thin AlGaN/AlN/GaN heterostructure with an only 100-nm-thick GaN spacer layer homoepitaxially grown on the GaN template. This technique was also demonstrated viable for native GaN substrates to stabilize the surface facilitating two-dimensional growth of GaN layers. Very high residual silicon andmore » oxygen concentrations were found up to ∼1 × 10{sup 20 }cm{sup −3} at the interface between the GaN epilayer and the native GaN substrate. Capacitance-voltage measurements confirmed that the residual carbon doping controlled by growth conditions of the GaN epilayer can be used to successfully compensate the donor-like impurities. State-of-the-art structural properties of a high-mobility AlGaN/AlN/GaN heterostructure was then realized on a 1 × 1 cm{sup 2} SI native GaN substrate; the full width at half maximum of the X-ray rocking curves of the GaN (002) and (102) peaks are only 21 and 14 arc sec, respectively. The surface morphology of the heterostructure shows uniform parallel bilayer steps, and no morphological defects were noticeable over the entire epi-wafer.« less

  6. Reducing Threshold of Multi Quantum Wells InGaN Laser Diode by Using InGaN/GaN Waveguide

    NASA Astrophysics Data System (ADS)

    Abdullah, Rafid A.; Ibrahim, Kamarulazizi

    2010-07-01

    ISE TCAD (Integrated System Engineering Technology Computer Aided Design) software simulation program has been utilized to help study the effect of using InGaN/GaN as a waveguide instead of conventional GaN waveguide for multi quantum wells violet InGaN laser diode (LD). Simulation results indicate that the threshold of the LD has been reduced by using InGaN/GaN waveguide where InGaN/GaN waveguide increases the optical confinement factor which leads to increase the confinement carriers at the active region of the LD.

  7. Predictions of ground states of LiGa and NaGa

    NASA Astrophysics Data System (ADS)

    Boldyrev, Alexander I.; Simons, Jack

    1996-11-01

    The ground and very low-lying excited states of LiGa and NaGa have been studied using high level ab initio techniques. At the QCISD(T)/6-311 + G(2df) level of theory, the 1Σ + state was found to be the most stable for both molecules. The equilibrium bond lengths and dissociation energies were found to be: R( LiGa) = 2.865 Å and D0(LiGa) = 22.3 kcal/mol and R( NaGa) = 3.174 Å and D0(NaGa) = 17.1 kcal/mol. Trends within the ground electronic states of LiB, NaB, LiAl, NaAl, LiGa and NaGa are discussed and predictions for related AlkM (Alk LiCs and MBTl) species are made.

  8. Ovary-derived precursor gibberellin A9 is essential for female flower development in cucumber.

    PubMed

    Pimenta Lange, Maria João; Lange, Theo

    2016-12-01

    Gibberellins (GAs) are hormones that control many aspects of plant development, including flowering. It is well known that stamen is the source of GAs that regulate male and bisexual flower development. However, little is known about the role of GAs in female flower development. In cucumber, high levels of GA precursors are present in ovaries and high levels of bioactive GA 4 are identified in sepals/petals, reflecting the expression of GA 20-oxidase and 3-oxidase in these organs, respectively. Here, we show that the biologically inactive precursor GA 9 moves from ovaries to sepal/petal tissues where it is converted to the bioactive GA 4 necessary for female flower development. Transient expression of a catabolic GA 2-oxidase from pumpkin in cucumber ovaries decreases GA 9 and GA 4 levels and arrests the development of female flowers, and this can be restored by application of GA 9 to petals thus confirming its function. Given that bioactive GAs can promote sex reversion of female flowers, movement of biologically inactive precursors, instead of the hormone itself, might help to maintain floral organ identity, ensuring fruit and seed production. © 2016. Published by The Company of Biologists Ltd.

  9. Carrier confinement effects of InxGa1-xN/GaN multi quantum disks with GaN surface barriers grown in GaN nanorods

    NASA Astrophysics Data System (ADS)

    Park, Youngsin; Chan, Christopher C. S.; Taylor, Robert A.; Kim, Nammee; Jo, Yongcheol; Lee, Seung W.; Yang, Woochul; Im, Hyunsik

    2018-04-01

    Structural and optical properties of InxGa1-xN/GaN multi quantum disks (QDisks) grown on GaN nanorods by molecular beam epitaxy have been investigated by transmission electron microscopy and micro-photoluminescence (PL) spectroscopy. Two types of InGaN QDisks were grown: a pseudo-3D confined InGaN pillar-type QDisks embedded in GaN nanorods; and QDisks in flanged cone type GaN nanorods. The PL emission peak and excitation dependent PL behavior of the pillar-type Qdisks differ greatly from those of the flanged cone type QDisks. Time resolved PL was carried out to probe the differences in charge carrier dynamics. The results suggest that by constraining the formation of InGaN QDisks within the centre of the nanorod, carriers are restricted from migrating to the surface, decreasing the surface recombination at high carrier densities.

  10. Role of GA3, GA4 and uniconazole-P in controlling gravitropism and tension wood formation in Fraxinus mandshurica Rupr. var. japonica Maxim. seedlings.

    PubMed

    Jiang, Sha; Xu, Ke; Wang, Yong-Zhou; Ren, Yan-Ping; Gu, Song

    2008-01-01

    GA(3) and GA(4) (gibberellins) play an important role in controlling gravitropism and tension wood formation in woody angiosperms. In order to improve our understanding of the role of GA(3) and GA(4) on xylem cell formation and the G-layer, we studied the effect of GA(3) and GA(4) and uniconazole-P, which is an inhibitor of GA biosynthesis, on tension wood formation by gravity in Fraxinus mandshurica Rupr. var. japonica Maxim. seedlings. Forty seedlings were divided into two groups; one group was placed upright and the other tilted. Each group was further divided into four sub-groups subjected to the following treatments: 3.43 x 10(-9) micromol acetone as control, 5.78 x 10(-8) micromol gibberellic acid (GA(3)), 6.21 x 10(-8) micromol GA(4), and 6.86 x 10(-8) micromol uniconazole-P. During the experimental period, GAs-treated seedlings exhibited negative gravitropism, whereas application of uniconazole-P inhibited negative gravitropic stem bending. GA(3) and GA(4) promoted wood fibers that possessed a gelatinous layer on the upper side, whereas uniconazole-P inhibited wood formation but did not inhibit the differentiation of the gelatinous layer in wood fibers on the upper side. These results suggest that: (i) both the formation of gelatinous fibers and the quantity of xylem production are important for the negative gravitropism in horizontally-positioned seedlings; (ii) GA(3) and GA(4) affect wood production more than differentiation of the gelatinous layer in wood fibers; G-layer development may be regulated by other hormones via the indirect-role of GA(3) and GA(4) in horizontally-positioned F. mandshurica seedlings rather than the direct effect of GAs; and (iii) the mechanism for upward wood stem bending is different to the newly developed shoot bending in reaction to gravity in this species.

  11. Muscular development and lean body weight in body builders and weight lifters.

    PubMed

    Katch, V L; Katch, F I; Moffatt, R; Gittleson, M

    1980-01-01

    The extent of extreme muscular development in 39 males identified as body builders (N = 18), power weight lifters (N = 13), and Olympic weight lifters (N = 8) were studied. Body composition and anthropometric data, including calculations of pre-excess muscle body weight (scale weight minus excess muscle) were obtained. The lean body weight and percent fats of the subjects were: body builders = 74.6 kg, 9.3%; power weight lifters = 73.3 kg, 9.1%; and Olympic weight lifters = 68.2 kg, 10.8%. No group differences were present in frame size, percent fat, lean body weight, skinfolds, and diameter measurements. The only group differences were for the shoulders, chest, biceps relaxed and flexed, and forearm girths. In each case the body builders were larger. Calculations of excess muscle by the Behnke method revealed that the body builders had 15.6 kg excess muscle, power weight lifters 14.8 kg, and Olympic weight lifters 13.1 kg. Somatographic comparisons revealed only slight differences between the groups, while differences with reference man were substantial.

  12. Ga@C-dots as an antibacterial agent for the eradication of Pseudomonas aeruginosa

    PubMed Central

    Kumar, Vijay Bhooshan; Natan, Michal; Jacobi, Gila; Porat, Ze’ev; Banin, Ehud; Gedanken, Aharon

    2017-01-01

    The opportunistic pathogen Pseudomonas aeruginosa causes infections that are difficult to treat by antibiotic therapy. This research article reports on the synthesis of gallium (Ga) doped in carbon (C)-dots (Ga@C-dots) and their antimicrobial activity against free-living P. aeruginosa bacteria. The synthesis of Ga@C-dots was carried out by sonicating molten Ga (for 2.5 h) in polyethylene glycol-400, which acts as both a medium and carbon source. The resultant Ga@C-dots, having an average diameter of 9±2 nm, showed remarkably enhanced antibacterial activity compared with undoped C-dots. This was reflected by the much lower concentration of Ga doped within Ga@C-dots which was required for full inhibition of the bacterial growth. These results highlight the possibility of using Ga@C-dots as potential antimicrobial agents. PMID:28176980

  13. Intrajugular Vein Delivery of AAV9-RNAi Prevents Neuropathological Changes and Weight Loss in Huntington's Disease Mice

    PubMed Central

    Dufour, Brett D; Smith, Catherine A; Clark, Randall L; Walker, Timothy R; McBride, Jodi L

    2014-01-01

    Huntington's disease (HD) is a fatal neurological disorder caused by a CAG repeat expansion in the HTT gene, which encodes a mutant huntingtin protein (mHTT). The mutation confers a toxic gain of function on huntingtin, leading to widespread neurodegeneration and inclusion formation in many brain regions. Although the hallmark symptom of HD is hyperkinesia stemming from striatal degeneration, several other brain regions are affected which cause psychiatric, cognitive, and metabolic symptoms. Additionally, mHTT expression in peripheral tissue is associated with skeletal muscle atrophy, cardiac failure, weight loss, and diabetes. We, and others, have demonstrated a prevention of motor symptoms in HD mice following direct striatal injection of adeno-associated viral vector (AAV) serotype 1 encoding an RNA interference (RNAi) construct targeting mutant HTT mRNA (mHTT). Here, we expand these efforts and demonstrate that an intrajugular vein injection of AAV serotype 9 (AAV9) expressing a mutant HTT-specific RNAi construct significantly reduced mHTT expression in multiple brain regions and peripheral tissues affected in HD. Correspondingly, this approach prevented atrophy and inclusion formation in key brain regions as well as the severe weight loss germane to HD transgenic mice. These results demonstrate that systemic delivery of AAV9-RNAi may provide more widespread clinical benefit for patients suffering from HD. PMID:24390280

  14. Concomitant changes in sleep duration and body weight and body composition during weight loss and 3-mo weight maintenance.

    PubMed

    Verhoef, Sanne P M; Camps, Stefan G J A; Gonnissen, Hanne K J; Westerterp, Klaas R; Westerterp-Plantenga, Margriet S

    2013-07-01

    An inverse relation between sleep duration and body mass index (BMI) has been shown. We assessed the relation between changes in sleep duration and changes in body weight and body composition during weight loss. A total of 98 healthy subjects (25 men), aged 20-50 y and with BMI (in kg/m(2)) from 28 to 35, followed a 2-mo very-low-energy diet that was followed by a 10-mo period of weight maintenance. Body weight, body composition (measured by using deuterium dilution and air-displacement plethysmography), eating behavior (measured by using a 3-factor eating questionnaire), physical activity (measured by using the validated Baecke's questionnaire), and sleep (estimated by using a questionnaire with the Epworth Sleepiness Scale) were assessed before and immediately after weight loss and 3- and 10-mo follow-ups. The average weight loss was 10% after 2 mo of dieting and 9% and 6% after 3- and 10-mo follow-ups, respectively. Daytime sleepiness and time to fall asleep decreased during weight loss. Short (≤7 h) and average (>7 to <9 h) sleepers increased their sleep duration, whereas sleep duration in long sleepers (≥9 h) did not change significantly during weight loss. This change in sleep duration was concomitantly negatively correlated with the change in BMI during weight loss and after the 3-mo follow-up and with the change in fat mass after the 3-mo follow-up. Sleep duration benefits from weight loss or vice versa. Successful weight loss, loss of body fat, and 3-mo weight maintenance in short and average sleepers are underscored by an increase in sleep duration or vice versa. This trial was registered at clinicaltrials.gov as NCT01015508.

  15. Legality Principle of Crimes and Punishments in Iranian Legal System

    ERIC Educational Resources Information Center

    Habibzadeh, Mohammad Ja'far

    2006-01-01

    The Principle of legality of crimes and punishments (nullum crimen, nulla poena sine lege) refers to the fact that an act is not considered a crime and deserves no punishment, unless the Legislator determines and announces the criminal title and its penalty before. The legality principle protects individual security by ensuring basic individual…

  16. [Is the legally responsible party indeed responsible? An ethical-legal question on the term].

    PubMed

    Fontana-Rosa, Júlio César; Oliveira, Reinaldo Ayer de

    2008-01-01

    The authors discuss the legal and ethical meaning of the expression "Third-Party Consent" by questioning its limits. It is indeed shown that it does not satisfactorily meet what is called third-party consent because this would require legal endorsement by legal codes and norms which, in fact does not occur. As such, the expression "third-party consent", whenever used, may not provide the professional with the normative, ethical and legal support needed for professional performance.

  17. Solving Single Machine Total Weighted Tardiness Problem with Unequal Release Date Using Neurohybrid Particle Swarm Optimization Approach.

    PubMed

    Cakar, Tarik; Koker, Rasit

    2015-01-01

    A particle swarm optimization algorithm (PSO) has been used to solve the single machine total weighted tardiness problem (SMTWT) with unequal release date. To find the best solutions three different solution approaches have been used. To prepare subhybrid solution system, genetic algorithms (GA) and simulated annealing (SA) have been used. In the subhybrid system (GA and SA), GA obtains a solution in any stage, that solution is taken by SA and used as an initial solution. When SA finds better solution than this solution, it stops working and gives this solution to GA again. After GA finishes working the obtained solution is given to PSO. PSO searches for better solution than this solution. Later it again sends the obtained solution to GA. Three different solution systems worked together. Neurohybrid system uses PSO as the main optimizer and SA and GA have been used as local search tools. For each stage, local optimizers are used to perform exploitation to the best particle. In addition to local search tools, neurodominance rule (NDR) has been used to improve performance of last solution of hybrid-PSO system. NDR checked sequential jobs according to total weighted tardiness factor. All system is named as neurohybrid-PSO solution system.

  18. Structures, bonding, and reaction chemistry of the neutral organogallium(I) compounds (GaAr)n(n = 1 or 2) (Ar = terphenyl or related ligand): an experimental investigation of Ga-Ga multiple bonding.

    PubMed

    Hardman, Ned J; Wright, Robert J; Phillips, Andrew D; Power, Philip P

    2003-03-05

    The synthesis, structure, and properties of several new organogallium(I) compounds are reported. The monovalent compounds GaAr* (Ar* = C(6)H(3)-2,6-Trip(2), Trip = C(6)H(2)-2,4,6-Pr(i)()(3), 1), GaAr# (Ar# = C(6)H(3)-2,6(Bu(t)Dipp)(2), Bu(t)Dipp = C(6)H(2)-2,6-Pr(i)(2)-4-Bu(t)(), 4), and the dimeric (GaAr')(2) (Ar' = C(6)H(3)-2,6-Dipp(2), Dipp = C(6)H(3)-2,6-Pr(i)(2), 6) were synthesized by the reaction of "GaI" with (Et(2)O)LiAr*, (Et(2)O)LiAr# (3), or (LiAr')(2). Compounds 1 and 4 were isolated as green crystals, whereas 6 was obtained as a brown-red crystalline solid. All three compounds dissolved in hydrocarbon solvents to give green solutions and almost identical UV/visible spectra. Cryoscopy of 1 and 6 showed that they were monomeric in cyclohexane. Crystals of 1 and 4 were unsuitable for X-ray crystal structure determinations, but an X-ray data set for 6 showed that it was weakly dimerized in the solid with a long Ga-Ga bond of 2.6268(7) A and a trans-bent CGaGaC core array. The 1,2-diiodo-1,2-diaryldigallane compounds [Ga(Ar*)I](2) (2), [Ga(Ar#)I](2) (5), and [Ga(Ar')I](2) (7) were isolated as byproducts of the synthesis of 1, 4, and 6. The crystal structures of 2 and 7 showed that they had planar ICGaGaCI core arrays with Ga-Ga distances near 2.49 A, consistent with Ga-Ga single bonding. Treatment of 1, 4, and 6 with B(C(6)F(5))(3) immediately afforded the 1:1 donor-acceptor complexes ArGa[B(C(6)F(5))(3)] (Ar = Ar*, 8; Ar#, 9; Ar', 10) that featured almost linear gallium coordination, Ga-B distances near the sum of the covalent radii of gallium and boron, as well as some close Ga...F contacts. Compound 1 also reacted with Fe(CO)(5) under ambient conditions to give Ar*GaFe(CO)(4) (11), which had been previously synthesized by the reaction of GaAr*Cl(2) with Na(2)Fe(CO)(4). Reaction of 1 with 2,3-dimethyl-1,3-butadiene afforded the compound [Ar*GaCH(2)C(Me)C(Me)CH(2)]2 (12) that had a 10-membered 1,5-Ga(2)C(8) ring with no Ga-Ga interaction. Stirring 1 or 6

  19. Carrier quenching in InGaP/GaAs double heterostructures

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

    Wells, Nathan P., E-mail: nathan.p.wells@aero.org; Driskell, Travis U.; Hudson, Andrew I.

    2015-08-14

    Photoluminescence measurements on a series of GaAs double heterostructures demonstrate a rapid quenching of carriers in the GaAs layer at irradiance levels below 0.1 W/cm{sup 2} in samples with a GaAs-on-InGaP interface. These results indicate the existence of non-radiative defect centers at or near the GaAs-on-InGaP interface, consistent with previous reports showing the intermixing of In and P when free As impinges on the InGaP surface during growth. At low irradiance, these defect centers can lead to sub-ns carrier lifetimes. The defect centers involved in the rapid carrier quenching can be saturated at higher irradiance levels and allow carrier lifetimes tomore » reach hundreds of nanoseconds. To our knowledge, this is the first report of a nearly three orders of magnitude decrease in carrier lifetime at low irradiance in a simple double heterostructure. Carrier quenching occurs at irradiance levels near the integrated Air Mass Zero (AM0) and Air Mass 1.5 (AM1.5) solar irradiance. Additionally, a lower energy photoluminescence band is observed both at room and cryogenic temperatures. The temperature and time dependence of the lower energy luminescence is consistent with the presence of an unintentional InGaAs or InGaAsP quantum well that forms due to compositional mixing at the GaAs-on-InGaP interface. Our results are of general interest to the photovoltaic community as InGaP is commonly used as a window layer in GaAs based solar cells.« less

  20. Visible-blind and solar-blind detection induced by defects in AlGaN high electron mobility transistors

    NASA Astrophysics Data System (ADS)

    Armstrong, Andrew M.; Klein, Brianna; Allerman, Andrew A.; Douglas, Erica A.; Baca, Albert G.; Crawford, Mary H.; Pickrell, Greg W.; Sanchez, Carlos A.

    2018-03-01

    Visible- and solar-blind detection was demonstrated using Al0.45Ga0.55N/Al0.30Ga0.70N and Al0.85Ga0.25N/Al0.70Ga0.30N high electron mobility transistors (HEMTs), respectively. Peak responsivities (S) of 3.9 × 106 A/W in the saturation mode and 6.2 × 104 A/W in the pinch-off mode were observed for the visible-blind Al0.45Ga0.55N/Al0.30Ga0.70N HEMT, and a peak S of 4.9 × 104 A/W was observed for the solar-blind Al0.85Ga0.15N/Al0.70Ga0.30N HEMT in the saturation mode. Spectrally resolved photocurrent investigation indicated that sub-bandgap absorption by defect states was the primary origin of the HEMTs' photoresponse. Defect-mediated responsivity caused slow photocurrent rise and fall times, but electrical pulsing was used to improve the bandwidth at the cost of optical gain. Operating HEMTs in this dynamic mode achieved a 25 Hz bandwidth with S = 2.9 × 105 A/W in accumulation and S = 2.0 × 104 A/W in pinch-off for visible-blind detection and S = 5.1 × 103 A/W for solar-blind detection.

  1. InGaAsN/GaAs heterojunction for multi-junction solar cells

    DOEpatents

    Kurtz, Steven R.; Allerman, Andrew A.; Klem, John F.; Jones, Eric D.

    2001-01-01

    An InGaAsN/GaAs semiconductor p-n heterojunction is disclosed for use in forming a 0.95-1.2 eV bandgap photodetector with application for use in high-efficiency multi-junction solar cells. The InGaAsN/GaAs p-n heterojunction is formed by epitaxially growing on a gallium arsenide (GaAs) or germanium (Ge) substrate an n-type indium gallium arsenide nitride (InGaAsN) layer having a semiconductor alloy composition In.sub.x Ga.sub.1-x As.sub.1-y N.sub.y with 0GaAs layer, with the InGaAsN and GaAs layers being lattice-matched to the substrate. The InGaAsN/GaAs p-n heterojunction can be epitaxially grown by either molecular beam epitaxy (MBE) or metalorganic chemical vapor deposition (MOCVD). The InGaAsN/GaAs p-n heterojunction provides a high open-circuit voltage of up to 0.62 volts and an internal quantum efficiency of >70%.

  2. Support for marijuana legalization in the US state of Washington has continued to increase through 2016*

    PubMed Central

    Subbaraman, Meenakshi Sabina; Kerr, William C.

    2017-01-01

    Background Support for the legalization of recreational marijuana continues to increase across the United States and globally. In 2016, recreational marijuana was legalized in the most populous US state of California, as well as three other states. The primary aim of this study was to examine trends in support for recreational marijuana legalization in Washington, a state which has had legal recreational marijuana for almost four years, using data collected over the four years post-legalization. A secondary aim was to examine trends in support for the cultivation of marijuana for personal use. Methods Data come from geographically representative general population samples of adult (aged 18 and over) Washington residents collected over five timepoints (every six months) between January 2014 and April 2016 (N = 4,101). Random Digit Dial was used for recruitment. Statistical analyses involved bivariate comparisons of proportions across timepoints and subgroups (defined by age, gender, and marijuana user status), and multivariable logistic regression controlling for timepoint (time) to formally test for trend while controlling for demographic and substance use covariates. All analyses adjusted for probability of selection. Results Support for legalization in Washington has significantly increased: support was 64.0% (95% CI: 61.2%–67.8%) at timepoint 1 and 77.9% (95% CI: 73.2%–81.9%) at timepoint 5. With each six months’ passing, support increased 19% on average. We found no statistically significant change in support for home-growing. Conclusions Support for marijuana legalization has continued to significantly increase in a state that has experienced the policy change for almost four years. PMID:28448904

  3. Support for marijuana legalization in the US state of Washington has continued to increase through 2016.

    PubMed

    Subbaraman, Meenakshi Sabina; Kerr, William C

    2017-06-01

    Support for the legalization of recreational marijuana continues to increase across the United States and globally. In 2016, recreational marijuana was legalized in the most populous US state of California, as well as three other states. The primary aim of this study was to examine trends in support for recreational marijuana legalization in Washington, a state which has had legal recreational marijuana for almost four years, using data collected over the four years post-legalization. A secondary aim was to examine trends in support for the cultivation of marijuana for personal use. Data come from geographically representative general population samples of adult (aged 18 and over) Washington residents collected over five timepoints (every six months) between January 2014 and April 2016 (N=4101). Random Digit Dial was used for recruitment. Statistical analyses involved bivariate comparisons of proportions across timepoints and subgroups (defined by age, gender, and marijuana user status), and multivariable logistic regression controlling for timepoint (time) to formally test for trend while controlling for demographic and substance use covariates. All analyses adjusted for probability of selection. Support for legalization in Washington has significantly increased: support was 64.0% (95% CI: 61.2%-67.8%) at timepoint 1 and 77.9% (95% CI: 73.2%-81.9%) at timepoint 5. With each six months' passing, support increased 19% on average. We found no statistically significant change in support for home-growing. Support for marijuana legalization has continued to significantly increase in a state that has experienced the policy change for almost four years. Copyright © 2017. Published by Elsevier B.V.

  4. Acyclic chelate with ideal properties for (68)Ga PET imaging agent elaboration.

    PubMed

    Boros, Eszter; Ferreira, Cara L; Cawthray, Jacqueline F; Price, Eric W; Patrick, Brian O; Wester, Dennis W; Adam, Michael J; Orvig, Chris

    2010-11-10

    We have investigated novel bifunctional chelate alternatives to the aminocarboxylate macrocycles NOTA (N(3)O(3)) or DOTA (N(4)O(4)) for application of radioisotopes of Ga to diagnostic nuclear medicine and have found that the linear N(4)O(2) chelate H(2)dedpa coordinates (67)Ga quantitatively to form [(67)Ga(dedpa)](+) after 10 min at RT. Concentration-dependent coordination to H(2)dedpa of either (68)Ga or (67)Ga showed quantitative conversion to the desired products with ligand concentrations as low as 10(-7) M. With (68)Ga, specific activities as high as 9.8 mCi nmol(-1) were obtained without purification. In a 2 h competition experiment against human apo-transferrin, [(67)Ga(dedpa)](+) showed no decomposition. Two bifunctional versions of H(2)dedpa are also described, and these both coordinate to (67)Ga at RT within 10 min. Complete syntheses, characterizations, labeling studies, and biodistribution profiles of the (67)Ga complexes are presented for the new platform chelates. The stability of these platform chelates is higher than that of DOTA.

  5. InGaN/GaN multilayer quantum dots yellow-green light-emitting diode with optimized GaN barriers.

    PubMed

    Lv, Wenbin; Wang, Lai; Wang, Jiaxing; Hao, Zhibiao; Luo, Yi

    2012-11-07

    InGaN/GaN multilayer quantum dot (QD) structure is a potential type of active regions for yellow-green light-emitting diodes (LEDs). The surface morphologies and crystalline quality of GaN barriers are critical to the uniformity of InGaN QD layers. While GaN barriers were grown in multi-QD layers, we used improved growth parameters by increasing the growth temperature and switching the carrier gas from N2 to H2 in the metal organic vapor phase epitaxy. As a result, a 10-layer InGaN/GaN QD LED is demonstrated successfully. The transmission electron microscopy image shows the uniform multilayer InGaN QDs clearly. As the injection current increases from 5 to 50 mA, the electroluminescence peak wavelength shifts from 574 to 537 nm.

  6. GaAsPN-based PIN solar cells MBE-grown on GaP substrates: toward the III-V/Si tandem solar cell

    NASA Astrophysics Data System (ADS)

    Da Silva, M.; Almosni, S.; Cornet, C.; Létoublon, A.; Levallois, C.; Rale, P.; Lombez, L.; Guillemoles, J.-F.; Durand, O.

    2015-03-01

    GaAsPN semiconductors are promising material for the elaboration of high efficiencies tandem solar cells on silicon substrates. GaAsPN diluted nitride alloy is studied as the top junction material due to its perfect lattice matching with the Si substrate and its ideal bandgap energy allowing a perfect current matching with the Si bottom cell. We review our recent progress in materials development of the GaAsPN alloy and our recent studies of some of the different building blocks toward the elaboration of a PIN solar cell. A lattice matched (with a GaP(001) substrate, as a first step toward the elaboration on a Si substrate) 1μm-thick GaAsPN alloy has been grown by MBE. After a post-growth annealing step, this alloy displays a strong absorption around 1.8-1.9 eV, and efficient photoluminescence at room temperature suitable for the elaboration of the targeted solar cell top junction. Early stage GaAsPN PIN solar cells prototypes have been grown on GaP (001) substrates, with 2 different absorber thicknesses (1μm and 0.3μm). The external quantum efficiencies and the I-V curves show that carriers have been extracted from the GaAsPN alloy absorbers, with an open-circuit voltage of 1.18 V, while displaying low short circuit currents meaning that the GaAsPN structural properties needs a further optimization. A better carrier extraction has been observed with the absorber displaying the smallest thickness, which is coherent with a low carriers diffusion length in our GaAsPN compound. Considering all the pathways for improvement, the efficiency obtained under AM1.5G is however promising.

  7. Growth of β-Ga2O3 and GaN nanowires on GaN for photoelectrochemical hydrogen generation.

    PubMed

    Hwang, Jih-Shang; Liu, Tai-Yan; Chattopadhyay, Surjit; Hsu, Geng-Ming; Basilio, Antonio M; Chen, Han-Wei; Hsu, Yu-Kuei; Tu, Wen-Hsun; Lin, Yan-Gu; Chen, Kuei-Hsien; Li, Chien-Cheng; Wang, Sheng-Bo; Chen, Hsin-Yi; Chen, Li-Chyong

    2013-02-08

    Enhanced photoelectrochemical (PEC) performances of Ga(2)O(3) and GaN nanowires (NWs) grown in situ from GaN were demonstrated. The PEC conversion efficiencies of Ga(2)O(3) and GaN NWs have been shown to be 0.906% and 1.09% respectively, in contrast to their 0.581% GaN thin film counterpart under similar experimental conditions. A low crystallinity buffer layer between the grown NWs and the substrate was found to be detrimental to the PEC performance, but the layer can be avoided at suitable growth conditions. A band bending at the surface of the GaN NWs generates an electric field that drives the photogenerated electrons and holes away from each other, preventing recombination, and was found to be responsible for the enhanced PEC performance. The enhanced PEC efficiency of the Ga(2)O(3) NWs is aided by the optical absorption through a defect band centered 3.3 eV above the valence band of Ga(2)O(3). These findings are believed to have opened up possibilities for enabling visible absorption, either by tailoring ion doping into wide bandgap Ga(2)O(3) NWs, or by incorporation of indium to form InGaN NWs.

  8. Red-emitting Ga/As,P///In,Ga/P heterojunction lasers

    NASA Technical Reports Server (NTRS)

    Kressel, H.; Nuese, C. J.; Olsen, G. H.

    1978-01-01

    The paper describes in detail the properties of vapor-grown double-heterojunction lasers of Ga(As,P)/(In,Ga)P with room-temperature threshold current densities as low as 3400 A/sq cm at 7000 A and 6600 A/sq cm at 6800 A. These thresholds are three to eight times smaller than those of (Al,Ga)As lasers in this wavelength range due to the shorter-wavelength direct-indirect transition in Ga(As,P). The optical and electrical characteristics of the Ga(As,P)/(In,Ga)P lasers are found to be similar to those of (Al,Ga)As, with fundamental transverse-mode operation to 70 C, and spontaneous carrier lifetimes between 5 and 8 nsec typically observed at low current densities.

  9. Pilot study of medical-legal partnership to address social and legal needs of patients.

    PubMed

    Weintraub, Dana; Rodgers, Melissa A; Botcheva, Luba; Loeb, Anna; Knight, Rachael; Ortega, Karina; Heymach, Brooke; Sandel, Megan; Huffman, Lynne

    2010-05-01

    As a preliminary investigation of the effectiveness of medical-legal partnership in pediatrics, we conducted a 36-month prospective cohort study of the impact of clinic- and hospital-based legal services. We hypothesized that integration of legal services into pediatric settings would increase families' awareness of and access to legal and social services, decrease barriers to health care for children, and improve child health. Health care providers referred families with legal or social needs to the Peninsula Family Advocacy Program (FAP). Fifty four families completed both baseline and six-month follow-up assessments. Comparison of follow-up with baseline demonstrated significantly increased proportions of families who utilized food and income supports and significantly decreased proportions of families avoiding health care due to lack of health insurance or concerns about cost. Two-thirds of respondents reported improved child health and well-being. This study suggests that adding an attorney to the medical team increases awareness of and access to social and legal services.

  10. A Metallurgical Study of Nāga Bhasma.

    PubMed

    Singh Gautam, Dev Nath

    2017-01-01

    The metal Nāga (Lead) is being used by Indians since ancient times. Its external and internal uses have been described in Caraka, Suśruta and other Ayurvedic Saṃhitā . According to most of the Rasa texts, Nāga Bhasma and its formulations are used in many diseases such as Prameha , Jvara , Gulma , Śukrameha etc. In the present study, Nāga Bhasma was prepared by the traditional Puṭa method (TPM) and by the electric muffle furnace Puṭa method (EMFPM) and standardized using Metallographic studies. Doing so helps in the study of the microstructure of Nāga Bhasma and also helps in the identification of the metal particles along with the nature of compound formed during the Māraṇa (Bhasmīkaraṇa) process. Different samples from initial raw material to final product of Nāga Bhasma were collected during the pharmaceutical process (1 st , 30 th and 60 th Puṭa ) from both methods i.e. TPM and EMFPM. Samples from both methods were studied using metallographic examination. The processing of the Nāga Bhasma ( ṣaṣṭipuṭa ) was done according to Ānanda Kanda [9] Samples from the raw material i.e. Aśodhita Nāga (raw Lead) and that processed after 1 st , 30 th and 60 th Puṭa from both methods i.e. traditional Puṭa method (using heat from burning of cow dung cakes) and electric muffle furnace Puṭa method were taken. They were mounted on self hardening acrylic base. After careful polishing to obtain scratch free surface of product, they were used for metallurgical study. This study shows that traditional Puṭa method may be better than electric muffle furnace Puṭa method because of more homogeneous distribution of Lead sulphide in the Nāga Bhasma which is prepared by traditional method.

  11. Electronic structure of β-Ga2O3 single crystals investigated by hard X-ray photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Guo-Ling; Zhang, Fabi; Cui, Yi-Tao; Oji, Hiroshi; Son, Jin-Young; Guo, Qixin

    2015-07-01

    By combination of hard X-ray photoelectron spectroscopy (HAXPES) and first-principles band structure calculations, the electronic states of β-Ga2O3 were investigated to deepen the understanding of bulk information for this compound. The valence band spectra of HAXPES presented the main contribution from Ga 4sp, which are well represented by photoionization cross section weighted partial density of states. The experimental data complemented with the theoretical study yield a realistic picture of the electronic structure for β-Ga2O3.

  12. Pilot Comparison of ⁶⁸Ga-RM2 PET and ⁶⁸Ga-PSMA-11 PET in Patients with Biochemically Recurrent Prostate Cancer.

    PubMed

    Minamimoto, Ryogo; Hancock, Steven; Schneider, Bernadette; Chin, Frederick T; Jamali, Mehran; Loening, Andreas; Vasanawala, Shreyas; Gambhir, Sanjiv Sam; Iagaru, Andrei

    2016-04-01

    Glu-NH-CO-NH-Lys-(Ahx)-[(68)Ga(HBED-CC)] ((68)Ga-PSMA-11) is a PET tracer that can detect prostate cancer relapses and metastases by binding to the extracellular domain of PSMA. (68)Ga-labeled DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2 ((68)Ga-RM2) is a synthetic bombesin receptor antagonist that targets gastrin-releasing peptide receptors. We present pilot data on the biodistribution of these PET tracers in a small cohort of patients with biochemically recurrent prostate cancer. Seven men (mean age ± SD, 74.3 ± 5.9 y) with biochemically recurrent prostate cancer underwent both (68)Ga-PSMA-11 PET/CT and (68)Ga-RM2 PET/MRI scans. SUVmax and SUVmean were recorded for normal tissues and areas of uptake outside the expected physiologic biodistribution. All patients had a rising level of prostate-specific antigen (mean ± SD, 13.5 ± 11.5) and noncontributory results on conventional imaging. (68)Ga-PSMA-11 had the highest physiologic uptake in the salivary glands and small bowel, with hepatobiliary and renal clearance noted, whereas (68)Ga-RM2 had the highest physiologic uptake in the pancreas, with renal clearance noted. Uptake outside the expected physiologic biodistribution did not significantly differ between (68)Ga-PSMA-11 and (68)Ga-RM2; however, (68)Ga-PSMA-11 localized in a lymph node and seminal vesicle in a patient with no abnormal (68)Ga-RM2 uptake. Abdominal periaortic lymph nodes were more easily visualized by(68)Ga-RM2 in two patients because of lack of interference by radioactivity in the small intestine. (68)Ga-PSMA-11 and (68)Ga-RM2 had distinct biodistributions in this small cohort of patients with biochemically recurrent prostate cancer. Additional work is needed to understand the expression of PSMA and gastrin-releasing peptide receptors in different types of prostate cancer. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  13. Are psychiatrists affecting the legal process by answering legal questions?

    PubMed

    Hardie, Timothy; Elcock, Susan; Mackay, R D

    2008-01-01

    Psychiatrists are often asked to answer legal questions. The extent to which they answer strictly legal rather than medical matters is not known. To investigate how strongly psychiatrists in England and Wales express opinions on one legal question - that of diminished responsibility in respect of a murder charge, and how this is related to outcome in court. METHOD Our data were extracted from psychiatric reports and case files supplied by the then Department of Constitutional Affairs (now the Ministry of Justice) on cases heard in the Crown Courts between 1 January 1997 and 31 December 2001 in which the defence of diminished responsibility had been raised. The cases had been selected by the Law Commission in their earlier review of partial defences to murder. We devised a reliable system of rating the presence/absence and strength of expression of a legal opinion in the medical reports. We tested the data for relationship between nature and strength of opinion and progression to trial and verdict. RESULTS Psychiatric reports were available on 143 of 156 cases in which diminished responsibility was considered. They yielded 338 opinions on at least one aspect of diminished responsibility. In 110 (93%) of the 118 cases in which there was a diminished verdict, this was made without trial and, therefore, without reference to a jury. In only eight (27%) out of the 30 cases that went to trial, was a diminished responsibility verdict made. Half of the reports (169) gave a clear opinion on diminished responsibility, a third (121) invited the court to draw a particular conclusion and only 11% (36) provided relevant evidence without answering the legal questions. When there was an opinion or an invitation to make a finding on the legal question, a trial was less likely. A trial was also less likely if reports agreed on what the verdict should be. CONCLUSIONS Psychiatrists frequently answer the legal question of diminished responsibility. The judiciary and medical experts

  14. Doping dependent blue shift and linewidth broadening of intersubband absorption in non-polar m-plane AlGaN/GaN multiple quantum wells

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

    Kotani, Teruhisa, E-mail: tkotani@iis.u-tokyo.ac.jp; Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505; Advanced Technology Research Laboratories, Sharp Corporation, 2613-1 Ichinomoto-cho, Tenri, Nara 632-8567

    2015-09-14

    Blue shift and broadening of the absorption spectra of mid-infrared intersubband transition in non-polar m-plane AlGaN/GaN 10 quantum wells were observed with increasing doping density. As the doping density was increased from 6.6 × 10{sup 11} to 6.0 × 10{sup 12 }cm{sup −2} per a quantum well, the intersubband absorption peak energy shifted from 274.0 meV to 302.9 meV, and the full width at half maximum increased from 56.4 meV to 112.4 meV. Theoretical calculations reveal that the blue shift is due to many body effects, and the intersubband linewidth in doped AlGaN/GaN QW is mainly determined by scattering due to interface roughness, LO phonons, and ionized impurities.

  15. Internal quantum efficiency in yellow-amber light emitting AlGaN-InGaN-GaN heterostructures

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

    Ngo, Thi Huong; Gil, Bernard; Valvin, Pierre

    2015-09-21

    We determine the internal quantum efficiency of strain-balanced AlGaN-InGaN-GaN hetero-structures designed for yellow-amber light emission, by using a recent model based on the kinetics of the photoluminescence decay initiated by Iwata et al. [J. Appl. Phys. 117, 075701 (2015)]. Our results indicate that low temperature internal quantum efficiencies sit in the 50% range and we measure that adding an AlGaN layer increases the internal quantum efficiency from 50% up to 57% with respect to the GaN-InGaN case. More dramatic, it almost doubles from 2.5% up to 4.3% at room temperature.

  16. 77 FR 39654 - Proposed Legal Interpretation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ...-0670] Proposed Legal Interpretation AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... legal interpretation in which the agency considered clarifying prior legal interpretations regarding... inadvertently assigned an incorrect docket number to the proposed legal interpretation. This document corrects...

  17. Asymmetric quantum-well structures for AlGaN/GaN/AlGaN resonant tunneling diodes

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

    Yang, Lin'an, E-mail: layang@xidian.edu.cn; Li, Yue; Wang, Ying

    Asymmetric quantum-well (QW) structures including the asymmetric potential-barrier and the asymmetric potential-well are proposed for AlGaN/GaN/AlGaN resonant tunneling diodes (RTDs). Theoretical investigation gives that an appropriate decrease in Al composition and thickness for emitter barrier as well as an appropriate increase of both for collector barrier can evidently improve the negative-differential-resistance characteristic of RTD. Numerical simulation shows that RTD with a 1.5-nm-thick GaN well sandwiched by a 1.3-nm-thick Al{sub 0.15}Ga{sub 0.85}N emitter barrier and a 1.7-nm-thick Al{sub 0.25}Ga{sub 0.75}N collector barrier can yield the I-V characteristic having the peak current (Ip) and the peak-to-valley current ratio (PVCR) of 0.39 A andmore » 3.6, respectively, about double that of RTD with a 1.5-nm-thick Al{sub 0.2}Ga{sub 0.8}N for both barriers. It is also found that an introduction of InGaN sub-QW into the diode can change the tunneling mode and achieve higher transmission coefficient of electron. The simulation demonstrates that RTD with a 2.8-nm-thick In{sub 0.03}Ga{sub 0.97}N sub-well in front of a 2.0-nm-thick GaN main-well can exhibit the I-V characteristic having Ip and PVCR of 0.07 A and 11.6, about 7 times and double the value of RTD without sub-QW, respectively. The purpose of improving the structure of GaN-based QW is to solve apparent contradiction between the device structure and the device manufacturability of new generation RTDs for sub-millimeter and terahertz applications.« less

  18. Process dependency on threshold voltage of GaN MOSFET on AlGaN/GaN heterostructure

    NASA Astrophysics Data System (ADS)

    Wang, Qingpeng; Jiang, Ying; Miyashita, Takahiro; Motoyama, Shin-ichi; Li, Liuan; Wang, Dejun; Ohno, Yasuo; Ao, Jin-Ping

    2014-09-01

    GaN metal-oxide-semiconductor field-effect transistors (MOSFETs) with recessed gate on AlGaN/GaN heterostructure are reported in which the drain and source ohmic contacts were fabricated on the AlGaN/GaN heterostructure and the electron channel was formed on the GaN buffer layer by removing the AlGaN barrier layer. Negative threshold voltages were commonly observed in all devices. To investigate the reasons of the negative threshold voltages, different oxide thickness, etching gas and bias power of inductively-coupled plasma (ICP) system were utilized in the fabrication process of the GaN MOSFETs. It is found that positive charges of around 1 × 1012 q/cm2 exist near the interface at the just threshold condition in both silane- and tetraethylorthosilicate (TEOS)-based devices. It is also found that the threshold voltages do not obviously change with the different etching gas (SiCl4, BCl3 and two-step etching of SiCl4/Cl2) at the same ICP bias power level (20-25 W) and will become deeper when higher bias power is used in the dry recess process which may be related to the much serious ion bombardment damage. Furthermore, X-ray photoelectron spectroscopy (XPS) experiments were done to investigate the surface conditions. It is found that N 1s peaks become lower with higher bias power of the dry etching process. Also, silicon contamination was found and could be removed by HNO3/HF solution. It indicates that the nitrogen vacancies are mainly responsible for the negative threshold voltages rather than the silicon contamination. It demonstrates that optimization of the ICP recess conditions and improvement of the surface condition are still necessary to realize enhancement-mode GaN MOSFETs on AlGaN/GaN heterostructure.

  19. Legal and Regulatory Barriers to Reverse Innovation.

    PubMed

    Rowthorn, Virginia; Plum, Alexander J; Zervos, John

    Reverse innovation, or the importation of new, affordable, and efficacious models to high-income countries from the developing world, has emerged as a way to improve the health care system in the United States. Reverse innovation has been identified as a key emerging trend in global health systems in part because low-resourced settings are particularly good laboratories for low-cost/high-impact innovations that are developed out of necessity. A difficult question receiving scant attention is that of legal and regulatory barriers. The objective of this paper is to understand and elucidate the legal barriers faced by innovators bringing health interventions to the United States. Semistructured qualitative interviews were conducted with 9 key informants who have directly participated in the introduction of global health care approaches to the United States health system. A purposive sampling scheme was employed to identify participants. Phone interviews were conducted over one week in July 2016 with each participant and lasted an average of 35 minutes each. Purely legal barriers included questions surrounding tort liability, standard of care, and concerns around patient-administered self-care. Regulatory burdens included issues of international medical licensure, reimbursement, and task shifting and scope of work challenges among nonprofessionals (e.g. community health workers). Finally, perceived (i.e. not realized or experienced) legal and regulatory barriers to innovative modalities served as disincentives to bringing products or services developed outside of the United States to the United States market. Conflicting interests within the health care system, safety concerns, and little value placed on low-cost interventions inhibit innovation. Legal and regulatory barriers rank among, and contribute to, an anti-innovation atmosphere in healthcare for domestic and reverse innovators alike. Reverse innovation should be fostered through the thoughtful development of

  20. Legal Support for Palliative Care Patients.

    PubMed

    Ezer, Tamar; Burke-Shyne, Naomi; Hepford, Kiera

    2018-02-01

    Palliative care patients face legal issues that impact their quality of life. Legal support, embedded in holistic palliative care services, has developed globally over the last decade to address this. This article aims to trace the origins of legal support for palliative care patients, detail models of legal support, and describe achievements and challenges. The article draws on years of work in this area and the available literature. Common legal issues include disposing of property and drafting wills, planning for children, dealing with debt and securing social benefits, and addressing discrimination. Diverse approaches to integrating legal support include developing paralegal skills, accessing skilled legal advice, empowering patients and families, and building awareness of rights among health care workers. There is robust and growing acceptance of legal support as a key component of holistic palliative care, and many palliative care professionals are identifying and addressing the legal needs they encounter through mediation, guidance on basic rights, or referrals to a lawyer. Addressing legal problems can contribute to peace of mind, well-being, and the health of patients. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  1. White emission from non-planar InGaN/GaN MQW LEDs grown on GaN template with truncated hexagonal pyramids.

    PubMed

    Lee, Ming-Lun; Yeh, Yu-Hsiang; Tu, Shang-Ju; Chen, P C; Lai, Wei-Chih; Sheu, Jinn-Kong

    2015-04-06

    Non-planar InGaN/GaN multiple quantum well (MQW) structures are grown on a GaN template with truncated hexagonal pyramids (THPs) featuring c-plane and r-plane surfaces. The THP array is formed by the regrowth of the GaN layer on a selective-area Si-implanted GaN template. Transmission electron microscopy shows that the InGaN/GaN epitaxial layers regrown on the THPs exhibit different growth rates and indium compositions of the InGaN layer between the c-plane and r-plane surfaces. Consequently, InGaN/GaN MQW light-emitting diodes grown on the GaN THP array emit multiple wavelengths approaching near white light.

  2. InGaN/GaN multilayer quantum dots yellow-green light-emitting diode with optimized GaN barriers

    PubMed Central

    2012-01-01

    InGaN/GaN multilayer quantum dot (QD) structure is a potential type of active regions for yellow-green light-emitting diodes (LEDs). The surface morphologies and crystalline quality of GaN barriers are critical to the uniformity of InGaN QD layers. While GaN barriers were grown in multi-QD layers, we used improved growth parameters by increasing the growth temperature and switching the carrier gas from N2 to H2 in the metal organic vapor phase epitaxy. As a result, a 10-layer InGaN/GaN QD LED is demonstrated successfully. The transmission electron microscopy image shows the uniform multilayer InGaN QDs clearly. As the injection current increases from 5 to 50 mA, the electroluminescence peak wavelength shifts from 574 to 537 nm. PMID:23134721

  3. Structural and optoelectronic properties of ZnGaO thin film by pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Han, Xiaowei; Wang, Li; Li, Shufeng; Gao, Dongwen; Pan, Yong

    2018-01-01

    ZnO has attracted much attention because of its high-energy gap and exciton binding energy at room temperature. Compared to ZnO thin films, ZnGaO thin films are more resistive to oxidation and have smaller deformation of lattice. In this study, the high purity ZnSe and Ga2O3 powders were weighted at a molar ratio of 18:1. Se was oxidized to Se2O3 and separated from the mixture powders by using conventional solid state reaction method in air, and the ZnGaO ceramic target was prepared. We fabricated the ZnGaO films on silica glass by pulsed laser deposition (PLD) method under different oxygen pressure at room temperature. The as-grown films were tested by X-ray diffraction and atomic force microscope (AFM) to diagnose the crystal structure and surface morphology. Moreover, we obtained the optical transmittance of ZnGaO film and found that the electrical conductivity capacity varied with the increase of oxygen pressure.

  4. GaAs quantum dots in a GaP nanowire photodetector

    NASA Astrophysics Data System (ADS)

    Kuyanov, P.; McNamee, S. A.; LaPierre, R. R.

    2018-03-01

    We report the structural, optical and electrical properties of GaAs quantum dots (QDs) embedded along GaP nanowires. The GaP nanowires contained p-i-n junctions with 15 consecutively grown GaAs QDs within the intrinsic region. The nanowires were grown by molecular beam epitaxy using the self-assisted vapor-liquid-solid process. The crystal structure of the NWs alternated between twinned ZB and WZ as the composition along the NW alternated between the GaP barriers and the GaAs QDs, respectively, leading to a polytypic structure with a periodic modulation of the NW sidewall facets. Photodetector devices containing QDs showed absorption beyond the bandgap of GaP in comparison to nanowires without QDs. Voltage-dependent measurements suggested a field emission process of carriers from the QDs.

  5. High-efficiency thin-film GaAs solar cells, phase2

    NASA Technical Reports Server (NTRS)

    Yeh, Y. C. M.

    1981-01-01

    Thin GaAs epi-layers with good crystallographic quality were grown using a (100) Si-substrate on which a thin Ge epi-interlayer was grown by CVD from germane. Both antireflection-coated metal oxide semiconductor (AMOS) and n(+)/p homojunction structures were studied. The AMOS cells were fabricated on undoped-GaAs epi-layers deposited on bulk poly-Ge substrates using organo-metallic CVD film-growth, with the best achieved AM1 conversion efficiency being 9.1%. Both p-type and n(+)-type GaAs growth were optimized using 50 ppm dimethyl zinc and 1% hydrogen sulfide, respectively. A direct GaAs deposition method in fabricating ultra-thin top layer, epitaxial n(+)/p shallow homojunction solar cells on (100) GaAs substrates (without anodic thinning) was developed to produce large area (1 sq/cm) cells, with 19.4% AM1 conversion efficiency achieved. Additionally, an AM1 conversion efficiency of 18.4% (17.5% with 5% grid coverage) was achieved for a single crystal GaAs n(+)/p cell grown by OM-CVD on a Ge wafer.

  6. Germanium- and tellurium-doped GaAs for non-alloyed p-type and n-type ohmic contacts

    NASA Astrophysics Data System (ADS)

    Park, Joongseo; Barnes, Peter A.; Lovejoy, Michael L.

    1995-08-01

    Epitaxial ohmic contacts to GaAs were grown by liquid phase epitaxy. Heavily Ge-doped GaAs was grown to prepare ohmic contacts to p-GaAs while Te was used for the n-type contacts. Hall measurements were carried out for the samples grown from melts in which the mole fraction of Ge was varied between 1.55 atomic % and 52.2 atomic %, while the Te mole fractions varied between 0.03% and 0.5%. Specific contact resistance, rc, as low as rcp=2.9×10-6 ohm-cm 2 for Ge doping of p=(Na-Nd)=6.0×1019 holes/cm3 was measured for p-contacts and rcn=9.6×10-5 ohm-cm2 was measured for Te doping of n=(Nd-Na)=8.9×1018 electrons/cm3 for GaAs metallized with non-alloyed contacts of Ti/Al.

  7. Physical and electrical characterizations of AlGaN/GaN MOS gate stacks with AlGaN surface oxidation treatment

    NASA Astrophysics Data System (ADS)

    Yamada, Takahiro; Watanabe, Kenta; Nozaki, Mikito; Shih, Hong-An; Nakazawa, Satoshi; Anda, Yoshiharu; Ueda, Tetsuzo; Yoshigoe, Akitaka; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji

    2018-06-01

    The impacts of inserting ultrathin oxides into insulator/AlGaN interfaces on their electrical properties were investigated to develop advanced AlGaN/GaN metal–oxide–semiconductor (MOS) gate stacks. For this purpose, the initial thermal oxidation of AlGaN surfaces in oxygen ambient was systematically studied by synchrotron radiation X-ray photoelectron spectroscopy (SR-XPS) and atomic force microscopy (AFM). Our physical characterizations revealed that, when compared with GaN surfaces, aluminum addition promotes the initial oxidation of AlGaN surfaces at temperatures of around 400 °C, followed by smaller grain growth above 850 °C. Electrical measurements of AlGaN/GaN MOS capacitors also showed that, although excessive oxidation treatment of AlGaN surfaces over around 700 °C has an adverse effect, interface passivation with the initial oxidation of the AlGaN surfaces at temperatures ranging from 400 to 500 °C was proven to be beneficial for fabricating high-quality AlGaN/GaN MOS gate stacks.

  8. 40 CFR 180.1098 - Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium Gibberellate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and GA4 + GA7), and Sodium or Potassium Gibberellate]; exemption from the requirement of a tolerance... Tolerances § 180.1098 Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium... potassium gibberellate] in or on all food commodities when used as plant regulators on plants, seeds, or...

  9. 40 CFR 180.1098 - Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium Gibberellate...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and GA4 + GA7), and Sodium or Potassium Gibberellate]; exemption from the requirement of a tolerance... Tolerances § 180.1098 Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium... potassium gibberellate] in or on all food commodities when used as plant regulators on plants, seeds, or...

  10. 40 CFR 180.1098 - Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium Gibberellate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and GA4 + GA7), and Sodium or Potassium Gibberellate]; exemption from the requirement of a tolerance... Tolerances § 180.1098 Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium... potassium gibberellate] in or on all food commodities when used as plant regulators on plants, seeds, or...

  11. 40 CFR 180.1098 - Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium Gibberellate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and GA4 + GA7), and Sodium or Potassium Gibberellate]; exemption from the requirement of a tolerance... Tolerances § 180.1098 Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium... potassium gibberellate] in or on all food commodities when used as plant regulators on plants, seeds, or...

  12. 40 CFR 180.1098 - Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium Gibberellate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and GA4 + GA7), and Sodium or Potassium Gibberellate]; exemption from the requirement of a tolerance... Tolerances § 180.1098 Gibberellins [Gibberellic Acids (GA3 and GA4 + GA7), and Sodium or Potassium... potassium gibberellate] in or on all food commodities when used as plant regulators on plants, seeds, or...

  13. Defining Legal Writing: An Empirical Analysis of the Legal Memorandum. LSAC Research Report Series.

    ERIC Educational Resources Information Center

    Breland, Hunter M.; Hart, Frederick M.

    This study examined legal writing as it was represented in legal memoranda prepared by first-semester law students at 12 different law schools. The study was based on the cumulative judgments of the instructors and professors of law in those institutions, humanities specialists at the Educational Testing Service, and two legal consultants. A…

  14. Fine structure of Fe-Co-Ga and Fe-Cr-Ga alloys with low Ga content

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

    Kleinerman, Nadezhda M., E-mail: kleinerman@imp.uran.ru; Serikov, Vadim V., E-mail: kleinerman@imp.uran.ru; Vershinin, Aleksandr V., E-mail: kleinerman@imp.uran.ru

    2014-10-27

    Investigation of Ga influence on the structure of Fe-Cr and Fe-Co alloys was performed with the use of {sup 57}Fe Mössbauer spectroscopy and X-ray diffraction methods. In the alloys of the Fe-Cr system, doping with Ga handicaps the decomposition of solid solutions, observed in the binary alloys, and increases its stability. In the alloys with Co, Ga also favors the uniformity of solid solutions. The analysis of Mössbauer experiments gives some grounds to conclude that if, owing to liquation, clusterization, or initial stages of phase separation, there exist regions enriched in iron, some amount of Ga atoms prefer to entermore » the nearest surroundings of iron atoms, thus forming binary Fe-Ga regions (or phases)« less

  15. Ga flux dependence of Er-doped GaN luminescent thin films

    NASA Astrophysics Data System (ADS)

    Lee, D. S.; Steckl, A. J.

    2002-02-01

    Er-doped GaN thin films have been grown on (111) Si substrates with various Ga fluxes in a radio frequency plasma molecular beam epitaxy system. Visible photoluminescence (PL) and electroluminescence (EL) emission at 537/558 nm and infrared (IR) PL emission at 1.5 μm from GaN:Er films exhibited strong dependence on the Ga flux. Both visible and IR PL and visible EL increase with the Ga flux up to the stoichiometric growth condition, as determined by growth rate saturation. Beyond this condition, all luminescence levels abruptly dropped to the detection limit with increasing Ga flux. The Er concentration, measured by secondary ion mass spectroscopy and Rutherford backscattering, decreases with increasing Ga flux under N-rich growth conditions and remains constant above the stoichiometric growth condition. X-ray diffraction indicated that the crystalline quality of the GaN:Er film was improved with increasing Ga flux up to stoichiometric growth condition and then saturated. Er ions in the films grown under N-rich conditions appear much more optically active than those in the films grown under Ga-rich conditions.

  16. 78 FR 14079 - Legal Processes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-04

    ... DEPARTMENT OF COMMERCE United States Patent and Trademark Office Legal Processes ACTION: Proposed... former employees of the United States Patent and Trademark Office (USPTO). The rules for these legal... employee testimony and production of documents in legal proceedings, reports of unauthorized testimony...

  17. 75 FR 3893 - Legal Processes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... DEPARTMENT OF COMMERCE Patent and Trademark Office Legal Processes ACTION: Proposed collection... legal processes may be found under 37 CFR Part 104, which outlines procedures for service of process, demands for employee testimony and production of documents in legal proceedings, reports of unauthorized...

  18. Did Legalized Abortion Lower Crime?

    ERIC Educational Resources Information Center

    Joyce, Ted

    2004-01-01

    Changes in homicide and arrest rates were compared among cohorts born before and after legalization of abortion and those who were unexposed to legalized abortion. It was found that legalized abortion improved the lives of many women as they could avoid unwanted births.

  19. Microstructural response of InGaN to swift heavy ion irradiation

    NASA Astrophysics Data System (ADS)

    Zhang, L. M.; Jiang, W.; Fadanelli, R. C.; Ai, W. S.; Peng, J. X.; Wang, T. S.; Zhang, C. H.

    2016-12-01

    A monocrystalline In0.18Ga0.82N film of ∼275 nm in thickness grown on a GaN/Al2O3 substrate was irradiated with 290 MeV 238U32+ ions to a fluence of 1.2 × 1012 cm-2 at room temperature. The irradiated sample was characterized using helium ion microscopy (HIM), Rutherford backscattering spectrometry under ion-channeling conditions (RBS/C), and high-resolution X-ray diffraction (HRXRD). The irradiation leads to formation of ion tracks throughout the thin In0.18Ga0.82N film and the 3.0 μm thick GaN buffer layer. The mean diameter of the tracks in In0.18Ga0.82N is ∼9 nm, as determined by HIM examination. Combination of the HIM and RBS/C data suggests that the In0.18Ga0.82N material in the track is likely to be highly disordered or fully amorphized. The irradiation induced lattice relaxation in In0.18Ga0.82N and a distribution of d-spacing of the (0 0 0 2) planes in GaN with lattice expansion are observed by HRXRD.

  20. Microstructural response of InGaN to swift heavy ion irradiation

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

    Zhang, L. M.; Jiang, W.; Fadanelli, R. C.

    2016-12-01

    A monocrystalline In0.18Ga0.82N film of ~275 nm in thickness grown on a GaN/Al 2O 3 substrate was irradiated with 290 MeV 238U 32+ ions to a fluence of 1.2 x 12 cm -2 at room temperature. The irradiated sample was characterized using helium ion microscopy (HIM), Rutherford backscattering spectrometry under ion-channeling conditions (RBS/C), and high-resolution x-ray diffraction (HRXRD). The irradiation leads to formation of ion tracks throughout the thin In 0.18Ga 0.82N film and the 3.0 µm thick GaN buffer layer. The mean diameter of the tracks in In 0.18Ga 0.82N is ~9 nm, as determined by HIM examination. Combinationmore » of the HIM and RBS/C data suggests that the material in the track is likely to be highly disordered or fully amorphized, in contrast to a crystalline structure within the ion track in GaN. Lattice relaxation in In0.18Ga0.82N and a distribution of d-spacing of the (0002) planes in GaN with lattice expansion are observed after irradiation.« less

  1. Study on the high-power semi-insulating GaAs PCSS with quantum well structure

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

    Luan, Chongbiao; Wang, Bo; Huang, Yupeng

    A high-power semi-insulating GaAs photoconductive semiconductor switch (PCSS) with quantum well structure was fabricated. The AlGaAs layer was deposited on the surface of the GaAs material, and the reflecting film and the antireflection film have been made on the surface of the GaAs and AlGaAs, respectively. When the prepared PCSS worked at a bias voltage of 9.8 kV and triggered by a laser pulse with an incident optical energy of 5.4 mJ, a wavelength of 1064 nm and an optical pulse width of 25 ns, the on-state resistance of the AlGaAs/GaAs PCSS was only 0.45 Ω, and the longevity ofmore » the AlGaAs/GaAs PCSS was larger than 10{sup 6} shots. The results show that this structure reduces the on-state resistance and extends the longevity of the GaAs PCSS.« less

  2. CO2 detection using polyethylenimine/starch functionalized AlGaN /GaN high electron mobility transistors

    NASA Astrophysics Data System (ADS)

    Chang, C. Y.; Kang, B. S.; Wang, H. T.; Ren, F.; Wang, Y. L.; Pearton, S. J.; Dennis, D. M.; Johnson, J. W.; Rajagopal, P.; Roberts, J. C.; Piner, E. L.; Linthicum, K. J.

    2008-06-01

    AlGaN /GaN high electron mobility transistors (HEMTs) functionalized with polyethylenimine/starch were used for detecting CO2 with a wide dynamic range of 0.9%-50% balanced with nitrogen at temperatures from 46to220°C. Higher detection sensitivity to CO2 gas was achieved at higher testing temperatures. At a fixed source-drain bias voltage of 0.5V, drain-source current of the functionalized HEMTs showed a sublinear correlation upon exposure to different CO2 concentrations at low temperature. The superlinear relationship was at high temperature. The sensor exhibited a reversible behavior and a repeatable current change of 32 and 47μA with the introduction of 28.57% and 37.5% CO2 at 108°C, respectively.

  3. GaSe and GaTe anisotropic layered semiconductors for radiation detectors

    NASA Astrophysics Data System (ADS)

    Mandal, Krishna C.; Choi, Michael; Kang, Sung Hoon; Rauh, R. David; Wei, Jiuan; Zhang, Hui; Zheng, Lili; Cui, Y.; Groza, M.; Burger, A.

    2007-09-01

    High quality detector grade GaSe and GaTe single crystals have been grown by a modified vertical Bridgman technique using high purity Ga (7N) and in-house zone refined (ZR) precursor materials (Se and Te). A state-of-the-art computer model, MASTRAPP, is used to model heat and mass transfer in the Bridgman growth system and to predict the stress distribution in the as-grown crystals. The model accounts for heat transfer in the multiphase system, convection in the melt, and interface dynamics. The crystals harvested from ingots of 8-10 cm length and 2.5 cm diameter, have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, low temperature photoluminescence (PL), atomic force microscopy (AFM), and optical absorption/transmission measurements. Single element devices up to 1 cm2 in area have been fabricated from the crystals and tested as radiation detectors by measuring current-voltage (I-V) characteristics and pulse height spectra using 241Am source. The crystals have shown high promise as nuclear detectors with their high dark resistivity (>=10 9 Ω .cm), good charge transport properties (μτ e ~ 1.4x10 -5 cm2/V and μτ h ~ 1.5x10 -5 cm2/V), and relatively good energy resolution (~4% energy resolution at 60 keV). Details of numerical modeling and simulation, detector fabrication, and testing using a 241Am energy source (60 keV) is presented in this paper.

  4. Fermi level dependence of hydrogen diffusivity in GaN

    NASA Astrophysics Data System (ADS)

    Polyakov, A. Y.; Smirnov, N. B.; Pearton, S. J.; Ren, F.; Theys, B.; Jomard, F.; Teukam, Z.; Dmitriev, V. A.; Nikolaev, A. E.; Usikov, A. S.; Nikitina, I. P.

    2001-09-01

    Hydrogen diffusion studies were performed in GaN samples with different Fermi level positions. It is shown that, at 350 °C, hydrogen diffusion is quite fast in heavily Mg doped p-type material with the Fermi level close to Ev+0.15 eV, considerably slower in high-resistivity p-GaN(Zn) with the Fermi level Ev+0.9 eV, while for conducting and semi-insulating n-GaN samples with the Fermi level in the upper half of the band gap no measurable hydrogen diffusion could be detected. For these latter samples it is shown that higher diffusion temperature of 500 °C and longer times (50 h) are necessary to incorporate hydrogen to appreciable depth. These findings are in line with previously published theoretical predictions of the dependence of hydrogen interstitials formation in GaN on the Fermi level position.

  5. High Piezoelectric Conversion Properties of Axial InGaN/GaN Nanowires.

    PubMed

    Jegenyes, Nikoletta; Morassi, Martina; Chrétien, Pascal; Travers, Laurent; Lu, Lu; Julien, Francois H; Tchernycheva, Maria; Houzé, Frédéric; Gogneau, Noelle

    2018-05-25

    We demonstrate for the first time the efficient mechanical-electrical conversion properties of InGaN/GaN nanowires (NWs). Using an atomic force microscope equipped with a modified Resiscope module, we analyse the piezoelectric energy generation of GaN NWs and demonstrate an important enhancement when integrating in their volume a thick In-rich InGaN insertion. The piezoelectric response of InGaN/GaN NWs can be tuned as a function of the InGaN insertion thickness and position in the NW volume. The energy harvesting is favoured by the presence of a PtSi/GaN Schottky diode which allows to efficiently collect the piezo-charges generated by InGaN/GaN NWs. Average output voltages up to 330 ± 70 mV and a maximum value of 470 mV per NW has been measured for nanostructures integrating 70 nm-thick InGaN insertion capped with a thin GaN top layer. This latter value establishes an increase of about 35% of the piezo-conversion capacity in comparison with binary p-doped GaN NWs. Based on the measured output signals, we estimate that one layer of dense InGaN/GaN-based NW can generate a maximum output power density of about 3.3 W/cm². These results settle the new state-of-the-art for piezo-generation from GaN-based NWs and offer a promising perspective for extending the performances of the piezoelectric sources.

  6. The Glycated Albumin (GA) to HbA1c Ratio Reflects Shorter-Term Glycemic Control than GA: Analysis of Patients with Fulminant Type 1 Diabetes.

    PubMed

    Koga, Masafumi; Inada, Shinya; Nakao, Taisei; Kawamori, Ryuzo; Kasayama, Soji

    2017-01-01

    Glycated albumin (GA) reflects shorter-term glycemic control than HbA1c. We have reported that HbA1c is paradoxically increased in diabetic patients whose glycemic control deteriorated before ameliorating. In this study, we analyzed paradoxical increases of glycemic control indicators after treatment in patients with fulminant type 1 diabetes (FT1D). We also investigated whether the GA/HbA1c ratio may reflect shorter-term glycemic control than GA. Five FT1D patients whose post-treatment HbA1c and GA levels were measured were enrolled. We also used a formula to estimate HbA1c and GA from the fictitious models of changes in plasma glucose in FT1D patients. In this model, the periods during which HbA1c, GA, and the GA/HbA1c ratio were higher than at the first visit were compared. In addition, the half-life for the GA/HbA1c ratio was calculated in accordance with the half-lives for HbA1c and GA (36 and 14 days, respectively). In all FT1D patients, HbA1c levels 2-4 weeks after treatment were increased, with three patients (60%) experiencing an increase of GA levels. In contrast, an increase of the GA/HbA1c ratio was observed in only one patient. In all of the different models of changes in plasma glucose in FT1D patients, the length of time during which the values were higher than at the first visit was in the order of HbA1c > GA > GA/HbA1c ratio. The half-life for the GA/HbA1c ratio was 9 days, shorter than GA. These findings suggest that the GA/HbA1c ratio reflects shorter-term glycemic control than GA. © 2016 Wiley Periodicals, Inc.

  7. Study of GaN nanorods converted from β-Ga2O3

    NASA Astrophysics Data System (ADS)

    Li, Yuewen; Xiong, Zening; Zhang, Dongdong; Xiu, Xiangqian; Liu, Duo; Wang, Shuang; Hua, Xuemei; Xie, Zili; Tao, Tao; Liu, Bin; Chen, Peng; Zhang, Rong; Zheng, Youdou

    2018-05-01

    We report here high-quality β-Ga2O3 nanorods (NRs) grown on sapphire substrates by hydrothermal method. Ammoniating the β-Ga2O3 NRs results in strain-free wurtzite gallium nitride (GaN) NRs. It was shown by XRD and Raman spectroscopy that β-Ga2O3 was partially converted to GaN/β-Ga2O3 at 1000 °C and then completely converted to GaN NRs at 1050 °C, as confirmed by high-resolution transmission electron microscopy (HRTEM). There is no band-edge emission of β-Ga2O3 in the cathodoluminescence spectrum, and only a deep-level broad emission observed at 3.68-3.73 eV. The band edge emission (3.39 eV) of GaN NRs converted from β-Ga2O3 can also be observed.

  8. Legal capacity of persons with disabilities in Ethiopia: The need to reform existing legal frameworks.

    PubMed

    Marishet, Mohammed Hamza

    The Convention on the Rights of Persons with Disabilities (CRPD) prohibited deprivation legal capacity of persons with disability based on assessment of mental capacity. The assertion is that, persons with disabilities shall exercise their legal capacity in all aspects of life without any restrictions that are based on mental incapacity (such as, unsoundness of mind, deficit in mental capacity, dotage, etc. This approach signifies a shift from substituted decision making, where another person act on behalf of persons with mental disabilities, to supported decision making where the person with mental disability is assisted in decision making. The rationale for the move lies on the recognition that the right to legal capacity embodies the inherent meaning of what it meant to be human. Without legal capacity a person cannot exercise all other rights and entitlements. Accordingly, States parties to CRPD are required to reform domestic legislations that are based on substituted decision making model and recognize full legal capacity of persons with disabilities in line with supported decision making model. As a Sate party to CRPD, Ethiopia assumed the same obligation. Nonetheless, in its initial report to the Committee on CRPD, the country denies existence of legislation that restricts legal capacity on the grounds of mental incapacity. This research found out that there are restrictions imposed on legal capacity of persons with disabilities on the basis of mental incapacity/disability. The research analyzed the approach employed to restrict legal capacity under the existing legal frameworks of Ethiopia vis-à-vis supported decision-making regime under CRPD. The research is doctrinal and, as such, limited to content analysis of general and specific legal capacity laws of the country (such as, marriage, divorce, will, work and employment, political participation, access to justice and others). Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Enhanced Electro-Static Discharge Endurance of GaN-Based Light-Emitting Diodes with Specially Designed Electron Blocking Layer

    NASA Astrophysics Data System (ADS)

    Wang, Chunxia; Zhang, Xiong; Guo, Hao; Chen, Hongjun; Wang, Shuchang; Yang, Hongquan; Cui, Yiping

    2013-10-01

    GaN-based light-emitting diodes (LEDs) with specially designed electron blocking layers (EBLs) between the multiple quantum wells (MQWs) and the top p-GaN layer have been developed. The EBLs consist of Mg-doped p-AlGaN/GaN superlattice (SL) with the layer thickness of p-AlGaN varied from 1 to 10 nm and the layer thickness of p-GaN fixed at 1 nm in this study. It was found that under a 2000 V reverse bias voltage condition, the electro-static discharge (ESD) yield increased from 61.98 to 99.51% as the thickness of p-AlGaN in the EBLs was increased from 1 to 10 nm. Since the ESD yield was 97.80%, and maximum value for LEDs' light output power (LOP) and minimum value for the forward voltage (Vf) were achieved when the thickness of p-AlGaN in the EBLs was 9 nm with a 20 mA injection current, it was concluded that the p-AlGaN/GaN SL EBLs with the combination of 9-nm-thick p-AlGaN and 1-nm-thick p-GaN would be beneficial to the fabrication of the GaN-based LEDs with high brightness, high ESD endurance, and low Vf.

  10. Engineering of electric field distribution in GaN(cap)/AlGaN/GaN heterostructures: theoretical and experimental studies

    NASA Astrophysics Data System (ADS)

    Gladysiewicz, M.; Janicki, L.; Misiewicz, J.; Sobanska, M.; Klosek, K.; Zytkiewicz, Z. R.; Kudrawiec, R.

    2016-09-01

    Polarization engineering of GaN-based heterostructures opens a way to develop advanced transistor heterostructures, although measurement of the electric field in such heterostructures is not a simple task. In this work, contactless electroreflectance (CER) spectroscopy has been applied to measure the electric field in GaN-based heterostructures. For a set of GaN(d  =  0, 5, 15, and 30 nm)/AlGaN(20 nm)/GaN(buffer) heterostructures a decrease of electric field in the GaN(cap) layer from 0.66 MV cm-1 to 0.27 MV cm-1 and an increase of the electric field in the AlGaN layer from 0.57 MV cm-1 to 0.99 MV cm-1 have been observed with the increase in the GaN(cap) thickness from 5-30 nm. For a set of GaN(20 nm)/AlGaN(d  =  10, 20, 30, and 40 nm)/GaN(buffer) heterostructures a decrease of the electric field in the AlGaN layer from 1.77 MV cm-1 to 0.64 MV cm-1 and an increase of the electric field in the GaN layer from 0.57 MV cm-1 to 0.99 MV cm-1 were observed with the increase in the AlGaN thickness from 10-40 nm. To determine the distribution of the electric field in these heterostructures the Schrödinger and Poisson equations are solved in a self-consistent manner and matched with experimental data. It is shown that the built-in electric field in the GaN(cap) and AlGaN layers obtained from measurements does not reach values of electric field resulting only from polarization effects. The measured electric fields are smaller due to a screening of polarization effects by free carriers, which are inhomogeneously distributed across the heterostructure and accumulate at interfaces. The results clearly demonstrate that CER measurements supported by theoretical calculations are able to determine the electric field distribution in GaN-based heterostructures quantitatively, which is very important for polarization engineering in this material system.

  11. Relationship between perilipin gene polymorphisms and body weight and body composition during weight loss and weight maintenance.

    PubMed

    Soenen, Stijn; Mariman, Edwin C M; Vogels, Neeltje; Bouwman, Freek G; den Hoed, Marcel; Brown, Louise; Westerterp-Plantenga, Margriet S

    2009-03-23

    Genetic variation in the perilipin (PLIN) gene may play a role in the etiology and treatment of obesity. To examine different polymorphisms in the PLIN gene in relation to body-weight regulation. 118 subjects followed a 6 wk VLCD, followed by 1 year weight maintenance. Body-weight (BW), body composition, leptin concentration, and polymorphisms of the PLIN gene: PLIN1:rs2289487, PLIN4:rs894160, PLIN6:rs1052700, PLIN5:rs2304795 and PLIN7:rs 2304796 were determined. BW loss during VLCD was 7.0+/-3.1 kg (p<0.05), and BW regain was 3.7+/-1.4 kg (p<0.05), including changes in body mass index (BMI), waist-circumference, body-composition and leptin concentrations (p<0.05). Linkage disequilibria were observed between PLIN1 and PLIN4: D' >0.9, r2=0.72; PLIN5 and PLIN7: D' >0.9, r2=0.85. In men, body weight, BMI, waist circumference, body fat, leptin concentrations were significantly lower for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). In women weight loss and loss of fat mass were larger for the haplotype of PLIN1 (C-alleles) and PLIN4 (A-alleles). For PLIN6 genotypes body weight and body fat were lower for homozygotes of the minor allele (T/T) in the men; in the women leptin concentrations were lower. The haplotype of PLIN5 and PLIN7 consisting of A/G and G/G of PLIN5 and A/A of PLIN7 showed a reduction in FM: 5.9+/-0.6 kg vs 3.1+/-0.4 kg, % body fat: 5.5+/-0.6% vs 2.2+/-0.2%, and leptin: 20.5+/-10.8 ng/ml vs 12.9+/-6.7 ng/ml over time in the women (p<0.05). Since the haplotype of the minor alleles PLIN1-4, PLIN5-7 and PLIN6, was related to body-weight regulation at a lower level of body-weight in the men as well in the women we conclude that the PLIN1-4, 6, and 5-7 locus appears as a genetic influencer of obesity risk in humans.

  12. The medico-legal investigation of abandoned fetuses and newborns--a review of cases admitted to the Pretoria Medico-Legal Laboratory, South Africa.

    PubMed

    du Toit-Prinsloo, L; Pickles, C; Smith, Z; Jordaan, J; Saayman, G

    2016-03-01

    There is a dearth of literature on the extent of fetal or newborn abandonment or "dumping" and the medico-legal investigation procedures these cases require. This is despite the fact that these occurrences are a worldwide phenomenon and by definition involve criminal law concerns such as illegal abortion, concealment of birth, murder, or neonaticide, depending on the country concerned. This article contributes to current literature in both respects and provides a retrospective case audit for the period 2004-2008 pertaining to all abandoned newborns and fetuses admitted to the Pretoria Medico-Legal Laboratory (PMLL) in South Africa. Demographic details, scope, and nature of the medico-legal investigation as well as formulation of cause of death were recorded. A total of 289 cases were identified for inclusion in this study, 57% of which were considered to have been non-viable fetuses, while 45 of the viable fetuses were deemed to have been stillborn. These instances involve the crimes of concealment of birth and at times illegal abortion, yet prosecution of these cases are relatively unheard of. Signs of live birth were identified in 38 of the cases in the study. Of these infants, 9 were deemed to have died from injuries they have sustained, and in a further 9 cases, no anatomical cause of death could be identified. Homicidal cases should be brought in cases where death ensued as a result of abandonment; however, it is not known how many cases were prosecuted. A comparatively large number of cases were found to have been admitted to the Pretoria Medico-Legal Laboratory. This is alarming because South African abortion laws are liberal and services are free at point of access in the public health care sector. A substantial percentage of cases of abandoned infants were found to have shown signs of life after birth implying a homicidal manner of death or death by abandonment, but it seems these cases are merely shelved.

  13. Electroluminescence of hot electrons in AlGaN/GaN high-electron-mobility transistors under radio frequency operation

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

    Brazzini, Tommaso, E-mail: tommaso.brazzini@bristol.ac.uk; Sun, Huarui; Uren, Michael J.

    2015-05-25

    Hot electrons in AlGaN/GaN high electron mobility transistors are studied during radio frequency (RF) and DC operation by means of electroluminescence (EL) microscopy and spectroscopy. The measured EL intensity is decreased under RF operation compared to DC at the same average current, indicating a lower hot electron density. This is explained by averaging the DC EL intensity over the measured load line used in RF measurements, giving reasonable agreement. In addition, the hot electron temperature is lower by up to 15% under RF compared to DC, again at least partially explainable by the weighted averaging along the specific load line.more » However, peak electron temperature under RF occurs at high V{sub DS} and low I{sub DS} where EL is insignificant suggesting that any wear-out differences between RF and DC stress of the devices will depend on the balance between hot-carrier and field driven degradation mechanisms.« less

  14. Ultralow-voltage-drop GaN/InGaN/GaN tunnel junctions with 12% indium content

    NASA Astrophysics Data System (ADS)

    Akyol, Fatih; Zhang, Yuewei; Krishnamoorthy, Sriram; Rajan, Siddharth

    2017-12-01

    We report a combination of highly doped layers and polarization engineering that achieves highly efficient blue-transparent GaN/InGaN/GaN tunnel junctions (In content = 12%). NPN diode structures with a low voltage drop of 4.04 V at 5 kA/cm2 and a differential resistance of 6.51 × 10-5 Ω·cm2 at 3 kA/cm2 were obtained. The tunnel junction design with n++-GaN (Si: 5 × 1020 cm-3)/3 nm p++-In0.12Ga0.88N (Mg: 1.5 × 1020 cm-3)/p++-GaN (Mg: 5 × 1020 cm-3) showed the best device performance. Device simulations agree well with the experimentally determined optimal design. The combination of low In composition and high doping can facilitate lower tunneling resistance for blue-transparent light-emitting diodes.

  15. White light emission of monolithic InGaN/GaN grown on morphology-controlled, nanostructured GaN templates.

    PubMed

    Song, Keun Man; Kim, Do-Hyun; Kim, Jong-Min; Cho, Chu-Young; Choi, Jehyuk; Kim, Kahee; Park, Jinsup; Kim, Hogyoug

    2017-06-02

    We demonstrated an InGaN/GaN-based, monolithic, white light-emitting diode (LED) without phosphors by using morphology-controlled active layers formed on multi-facet GaN templates containing polar and semipolar surfaces. The nanostructured surface morphology was controlled by changing the growth time, and distinct multiple photoluminescence peaks were observed at 360, 460, and 560 nm; these features were caused by InGaN/GaN-based multiple quantum wells (MQWs) on the nanostructured facets. The origin of each multi-peak was related to the different indium (In) compositions in the different planes of the quantum wells grown on the nanostructured GaN. The emitting units of MQWs in the LED structures were continuously connected, which is different from other GaN-based nanorod or nanowire LEDs. Therefore, the suggested structure had a larger active area. From the electroluminescence spectrum of the fabricated LED, monolithic white light emission with CIE color coordinates of x = 0.306 and y = 0.333 was achieved via multi-facet control combined with morphology control of the metal organic chemical vapor deposition-selective area growth of InGaN/GaN MQWs.

  16. White light emission of monolithic InGaN/GaN grown on morphology-controlled, nanostructured GaN templates

    NASA Astrophysics Data System (ADS)

    Song, Keun Man; Kim, Do-Hyun; Kim, Jong-Min; Cho, Chu-Young; Choi, Jehyuk; Kim, Kahee; Park, Jinsup; Kim, Hogyoug

    2017-06-01

    We demonstrated an InGaN/GaN-based, monolithic, white light-emitting diode (LED) without phosphors by using morphology-controlled active layers formed on multi-facet GaN templates containing polar and semipolar surfaces. The nanostructured surface morphology was controlled by changing the growth time, and distinct multiple photoluminescence peaks were observed at 360, 460, and 560 nm; these features were caused by InGaN/GaN-based multiple quantum wells (MQWs) on the nanostructured facets. The origin of each multi-peak was related to the different indium (In) compositions in the different planes of the quantum wells grown on the nanostructured GaN. The emitting units of MQWs in the LED structures were continuously connected, which is different from other GaN-based nanorod or nanowire LEDs. Therefore, the suggested structure had a larger active area. From the electroluminescence spectrum of the fabricated LED, monolithic white light emission with CIE color coordinates of x = 0.306 and y = 0.333 was achieved via multi-facet control combined with morphology control of the metal organic chemical vapor deposition-selective area growth of InGaN/GaN MQWs.

  17. Negative differential resistance in low Al-composition p-GaN/Mg-doped Al0.15Ga0.85N/n+-GaN hetero-junction grown by metal-organic chemical vapor deposition on sapphire substrate

    NASA Astrophysics Data System (ADS)

    Zhang, Kexiong; Liang, Hongwei; Shen, Rensheng; Wang, Dongsheng; Tao, Pengcheng; Liu, Yang; Xia, Xiaochuan; Luo, Yingmin; Du, Guotong

    2014-02-01

    Negative differential resistance (NDR) behavior was observed in low Al-composition p-GaN/Mg-doped-Al0.15Ga0.85N/n+-GaN hetero-junction grown by metal-organic chemical vapor deposition on sapphire substrate. The energy band and free carrier concentration of hetero-junction were studied by the model of the self-consistent solution of Schrödinger-Poisson equations combined with polarization engineering theory. At the forward bias of 0.95 V, the NDR effect has a high peak-to-valley current ratio of ˜9 with a peak current of 22.4 mA (˜current density of 11.4 A/cm2). An interesting phenomenon of NDR disappearance after consecutive scans and recurrence after electrical treatment was observed, which was associated with Poole-Frenkel effect.

  18. Sc(2)MgGa(2) and Y(2)MgGa(2).

    PubMed

    Sahlberg, Martin; Andersson, Yvonne

    2009-03-01

    Scandium magnesium gallide, Sc(2)MgGa(2), and yttrium magnesium gallide, Y(2)MgGa(2), were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo(2)FeB(2)-type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc(2)MgGa(2 )was determined from single-crystal diffraction intensities and the isostructural Y(2)MgGa(2) was identified from powder diffraction data.

  19. Investigation of GaAs/Al(x)Ga(1-x)As and In(y)Ga(1-y)As/GaAs superlattices on Si substrates

    NASA Technical Reports Server (NTRS)

    Reddy, U. K.; Ji, G.; Huang, D.; Munns, G.; Morkoc, H.

    1987-01-01

    The optical properties of lattice-matched GaAs/Al(x)Ga(1-x)As and In(y)Ga(1-y)As/GaAs strained-layer superlattices grown on Si substrates have been studied using the photoreflectance technique. These preliminary results show that good quality III-IV epilayers can be grown on Si. The experimental data were compared with calculations based on the envelope-function approximation and fitted to the third-derivative functional form of reflectance modulation theory.

  20. Weight and weight gain during early infancy predict childhood obesity: a case-cohort study.

    PubMed

    Andersen, L G; Holst, C; Michaelsen, K F; Baker, J L; Sørensen, T I A

    2012-10-01

    Infant weight and weight gain are positively associated with later obesity, but whether there is a particular critical time during infancy remains uncertain. The aim was to investigate when and how weight and weight gain during infancy become associated with childhood obesity. In a cohort representing 28 340 children born from 1959-67 and measured in Copenhagen schools, 962 obese children (2007 World Health Organization criteria), were compared with a 5% randomly selected sub-cohort of 1417 children. Information on weight at birth, 2 weeks, 1, 2, 3, 4, 6 and 9 months was retrieved from health visitors' records. Odds ratios and 95% confidence intervals (CI) for childhood obesity by tertiles of weight at each age and by change in tertiles of weight between two consecutive measurements were estimated using multivariate logistic regression with adjustment for indicators of socioeconomic status, preterm birth, and breastfeeding. Compared with children in the middle weight-tertile, children with a weight in the upper tertile had a 1.36-fold (CI, 1.10-1.69) to 1.72-fold (CI, 1.36-2.18) higher risk of childhood obesity from birth through 9 months, whereas children in the lower weight-tertile had almost half the risk of obesity from 2 through 9 months. The risk of childhood obesity associated with change in weight-tertile in each interval was stable at ∼1.5-fold per weight-tertile increase throughout infancy. Infant weight and weight gain are associated with obesity in childhood already during the first months of life. Determinants of weight gain shortly after birth may be a suitable target for prevention of obesity.

  1. Formation of two-dimensionally confined superparamagnetic (Mn, Ga)As nanocrystals in high-temperature annealed (Ga, Mn)As/GaAs superlattices.

    PubMed

    Sadowski, Janusz; Domagala, Jaroslaw Z; Mathieu, Roland; Kovacs, Andras; Dłużewski, Piotr

    2013-05-15

    The annealing-induced formation of (Mn, Ga)As nanocrystals in (Ga, Mn)As/GaAs superlattices was studied by x-ray diffraction, transmission electron microscopy and magnetometry. The superlattice structures with 50 Å thick (Ga, Mn)As layers separated by 25, 50 and 100 Å thick GaAs spacers were grown by molecular beam epitaxy at low temperature (250 °C), and then annealed at high temperatures of 400, 560 and 630 °C. The high-temperature annealing causes decomposition to a (Ga, Mn)As ternary alloy and the formation of (Mn, Ga)As nanocrystals inside the GaAs matrix. The nanocrystals are confined in the planes that were formerly occupied by (Ga, Mn)As layers for the up to 560 °C annealing and diffuse throughout the GaAs spacer layers at 630 °C annealing. The two-dimensionally confined nanocrystals exhibit a superparamagnetic behavior which becomes high-temperature ferromagnetism (~350 K) upon diffusion.

  2. Magnetoresistance Study in a GaAs/InGaAs/GaAs Delta-Doped Quantum Well

    NASA Astrophysics Data System (ADS)

    Hasbun, J. E.

    1997-03-01

    The magnetoresistance of a GaAs/Ga_0.87In_0.13As/GaAs with an electron concentration of N_s=6.3x10^11cm-2 is calculated at low temperature for a magnetic field range of 2-30 tesla and low electric field. The results obtained for the magnetotransport are compared with the experimental work of Herfort et al.(J. Herfort, K.-J. Friedland, H. Kostial, and R. Hey, Appl. Phys. Lett. V66, 23 (1995)). While the logitudinal magnetoresistance agrees reasonably well with experiment, the Hall resistance slope reflects a classical shape; however, its second derivative seems to show oscillations that are consistent with the Hall effect plateaus seen experimentally. Albeit with a much higher electron concentration, earlier calculationsfootnote J. Hasbun, APS Bull. V41, 419 (1996) for an Al_0.27Ga_0.73/GaAs /Al_0.27Ga_0.73As quantum well shows similar behavior. This work has been carried out with the use of a quantum many body approach employed in earlier work(J. Hasbun, APS Bull. V41, 1659 (1996)).

  3. 38 CFR 13.58 - Legal custodian.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Legal custodian. 13.58... ADMINISTRATION, FIDUCIARY ACTIVITIES § 13.58 Legal custodian. (a) Authority. The Veterans Service Center Manager is authorized to make determinations as to the person or legal entity to be appointed legal custodian...

  4. 38 CFR 13.58 - Legal custodian.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Legal custodian. 13.58... ADMINISTRATION, FIDUCIARY ACTIVITIES § 13.58 Legal custodian. (a) Authority. The Veterans Service Center Manager is authorized to make determinations as to the person or legal entity to be appointed legal custodian...

  5. 38 CFR 13.58 - Legal custodian.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Legal custodian. 13.58... ADMINISTRATION, FIDUCIARY ACTIVITIES § 13.58 Legal custodian. (a) Authority. The Veterans Service Center Manager is authorized to make determinations as to the person or legal entity to be appointed legal custodian...

  6. 38 CFR 13.58 - Legal custodian.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Legal custodian. 13.58... ADMINISTRATION, FIDUCIARY ACTIVITIES § 13.58 Legal custodian. (a) Authority. The Veterans Service Center Manager is authorized to make determinations as to the person or legal entity to be appointed legal custodian...

  7. 38 CFR 13.58 - Legal custodian.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Legal custodian. 13.58... ADMINISTRATION, FIDUCIARY ACTIVITIES § 13.58 Legal custodian. (a) Authority. The Veterans Service Center Manager is authorized to make determinations as to the person or legal entity to be appointed legal custodian...

  8. Overview of the TREC 2009 Legal Track

    DTIC Science & Technology

    2009-11-01

    on the IIT CDIP 1.0 collection [9]), we turned, in 2009, to a collection of emails that had been produced by Enron in response to requests from the...collection as the 2006–2008 Legal Tracks, the IIT Complex Document Information Processing ( CDIP ) Test Collection, version 1.0 (referred to here as “IIT... CDIP 1.0”) which is based on scanned documents released under the tobacco “Master Settlement Agreement” (MSA). The University of California San

  9. A Legal Handbook.

    ERIC Educational Resources Information Center

    Cincinnati Public Schools, OH.

    This publication was developed by the Cincinnati (Ohio) Public Schools for use as a resource in adult basic education classes. It presents, in simple format, the basic legal rights of citizens of the United States and points out legal problem areas that average adults may encounter in daily life. The book is organized into nine parts containing 2…

  10. Accreditation's Legal Landscape

    ERIC Educational Resources Information Center

    Graca, Thomas J.

    2009-01-01

    Like most issues in higher education, the accreditation paradigm in the United States is defined in large measure by the legal and political climate in which the academy finds itself. In the case of accreditation in particular, the legal substrate is of particular importance given the central role of accreditation in a college's ability to receive…

  11. A rare mutation in AgRP, +79G>A, affects promoter activity.

    PubMed

    Sözen, M A; de Jonge, L H M; Greenway, F; Ravussin, E; Smith, S R; Argyropoulos, G

    2007-06-01

    The agouti-related protein is a powerful orexigenic peptide. A rare mutation, +79G>A, was identified in its minimal promoter in two white carriers. Comparison of the 45-year-old male proband, who was also a carrier of the common Ala67Thr polymorphism, with an age- and weight-matching wild-type population showed marginal differences for resting metabolic rate (RMR) and body mass index. The second carrier however was an obese 57-year-old female with reduced RMR. Functional analysis in hypothalamus- and periphery-derived cell lines showed reduced promoter activity for the +79A allele in the adrenocortical cells only, suggesting that it could affect the peripheral expression levels of AgRP. The +79G>A mutation could predispose to body weight gain (as suggested by the phenotype of the second carrier), but it could only affect the proband at an older age as he may be protected by the Ala67Thr polymorphism that is associated with resistance to late-onset fatness.

  12. 32 CFR 724.703 - Legal counsel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Legal counsel. 724.703 Section 724.703 National... Organization of the Naval Discharge Review Board § 724.703 Legal counsel. Normally, the NDRB shall function without the immediate attendance of legal counsel. In the event that a legal advisory opinion is deemed...

  13. 32 CFR 724.703 - Legal counsel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Legal counsel. 724.703 Section 724.703 National... Organization of the Naval Discharge Review Board § 724.703 Legal counsel. Normally, the NDRB shall function without the immediate attendance of legal counsel. In the event that a legal advisory opinion is deemed...

  14. 32 CFR 724.703 - Legal counsel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Legal counsel. 724.703 Section 724.703 National... Organization of the Naval Discharge Review Board § 724.703 Legal counsel. Normally, the NDRB shall function without the immediate attendance of legal counsel. In the event that a legal advisory opinion is deemed...

  15. 32 CFR 724.703 - Legal counsel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Legal counsel. 724.703 Section 724.703 National... Organization of the Naval Discharge Review Board § 724.703 Legal counsel. Normally, the NDRB shall function without the immediate attendance of legal counsel. In the event that a legal advisory opinion is deemed...

  16. 32 CFR 724.703 - Legal counsel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Legal counsel. 724.703 Section 724.703 National... Organization of the Naval Discharge Review Board § 724.703 Legal counsel. Normally, the NDRB shall function without the immediate attendance of legal counsel. In the event that a legal advisory opinion is deemed...

  17. Ethical and legal issues.

    PubMed

    Talom, J M

    1996-01-01

    At the 9th International Conference on AIDS and Sexually Transmitted Diseases in Africa (ICASA), issues concerning the legal and ethical aspects of HIV/AIDS are brought to the fore. Throughout the world, people living with HIV/AIDS are experiencing various forms of human rights abuses including testing abuses, lack of confidentiality, refusal to treat patients, dismissal of HIV-positive employees without sufficient reason, invasion of privacy, and placement of infected subjects in quarantine. This discrimination and stigmatization is not justified and gravely compromises the considerable efforts already made in fighting the epidemic. Participants suggested that the law should be used to support the authority of individuals infected with HIV/AIDS. Legislation should follow a double objective: it should know that victims of AIDS should be protected and supported, and it should clearly indicate what the responsibility of seropositive persons vis a vis society could be. The controversy of whether it is necessary to enact a legislation concerning HIV/AIDS, however, remained. While some people believed that the existing legal framework could be exploited to develop the necessary protocol concerning the responsibilities and rights of patients, an opposing viewpoint is that current legislation should not be applied in solving the problems associated with HIV/AIDS. But the important interest is that numerous recommendations of the ICASA will not remain simple declarations of intention, but translated into correct actions.

  18. Potential Policies and Laws to Prohibit Weight Discrimination: Public Views from 4 Countries

    PubMed Central

    Puhl, Rebecca M; Latner, Janet D; O’brien, Kerry S; Luedicke, Joerg; Danielsdottir, Sigrun; Salas, Ximena Ramos

    2015-01-01

    Context People viewed as “overweight” or “obese” are vulnerable to weight-based discrimination, creating inequities and adverse health outcomes. Given the high rates of obesity recorded globally, studies documenting weight discrimination in multiple countries, and an absence of legislation to address this form of discrimination, research examining policy remedies across different countries is needed. Our study provides the first multinational examination of public support for policies and legislation to prohibit weight discrimination. Methods Identical online surveys were completed by 2,866 adults in the United States, Canada, Australia, and Iceland. We assessed public support for potential laws to prohibit weight-based discrimination, such as adding body weight to existing civil rights statutes, extending disability protections to persons with obesity, and instituting legal measures to prohibit employers from discriminating against employees because of body weight. We examined sociodemographic and weight-related characteristics predicting support for antidiscrimination policies, and the differences in these patterns across countries. Findings The majority of participants in the United States, Canada, and Australia agreed that their government should have specific laws in place to prohibit weight discrimination. At least two-thirds of the participants in all 4 countries expressed support for policies that would make it illegal for employers to refuse to hire, assign lower wages, deny promotions, or terminate qualified employees because of body weight. Women and participants with higher body weight expressed more support for antidiscrimination measures. Beliefs about the causes of obesity were also related to support for these laws. Conclusions Public support for legal measures to prohibit weight discrimination can be found in the United States, Canada, Australia, and Iceland, especially for laws to remedy this discrimination in employment. Our findings

  19. High-Temperature Thermoelectric and Microstructural Characteristics of Cobalt-Based Oxides with Ga Substituted on the Co-Site

    NASA Astrophysics Data System (ADS)

    Nong, N. V.; Yanagiya, S.; Monica, S.; Pryds, N.; Ohtaki, M.

    2011-05-01

    The effects of Ga substitution on the Co-site on the high-temperature thermoelectric properties and microstructure are investigated for the misfitlayered Ca3Co4O9 and the complex perovskite-related Sr3RECo4O10.5 (RE = rare earth) cobalt-based oxides. For both systems, substitution of Ga for Co results in a simultaneous increase in the Seebeck coefficient ( S) and the electrical conductivity ( σ), and the influence is more significant in the high temperature region. The power factor ( S 2 σ) is thereby remarkably improved by Ga substitution, particularly at high temperatures. Texture factor calculations using x-ray diffraction pattern data for pressed and powder samples reveal that the Ga-doped samples are highly textured. Microstructure observed by scanning electron microscopy shows very well-crystallized grains for the samples with Ga substitution for Co. Among the Ga-doped samples, Ca3Co3.95Ga0.05O9 shows the best ZT value of 0.45 at 1200 K, which is about 87.5% higher than the nondoped one, a considerable improvement.

  20. Against a singular understanding of legal capacity: Criminal responsibility and the Convention on the Rights of Persons with Disabilities.

    PubMed

    Craigie, Jillian

    2015-01-01

    The United Nations Convention on the Rights of Persons with Disabilities (CRPD) is being used to argue for wider recognition of the legal capacity of people with mental disabilities. This raises a question about the implications of the Convention for attributions of criminal responsibility. The present paper works towards an answer by analysing the relationship between legal capacity in relation to personal decisions and criminal acts. Its central argument is that because moral and political considerations play an essential role in setting the relevant standards, legal capacity in the context of personal decisions and criminal acts should not be thought of as two sides of the same coin. The implications of particular moral or political norms are likely to be different in these two legal contexts, and this may justify asymmetries in the relevant standards for legal capacity. However, the analysis highlights a fundamental question about how much weight moral or political considerations should be given in setting these standards, and this is used to frame a challenge to those calling for significantly wider recognition of the legal capacity of people with mental disabilities on the basis of the Convention. Copyright © 2015. Published by Elsevier Ltd.

  1. Against a singular understanding of legal capacity: Criminal responsibility and the Convention on the Rights of Persons with Disabilities

    PubMed Central

    Craigie, Jillian

    2015-01-01

    The United Nations Convention on the Rights of Persons with Disabilities (CRPD) is being used to argue for wider recognition of the legal capacity of people with mental disabilities. This raises a question about the implications of the Convention for attributions of criminal responsibility. The present paper works towards an answer by analysing the relationship between legal capacity in relation to personal decisions and criminal acts. Its central argument is that because moral and political considerations play an essential role in setting the relevant standards, legal capacity in the context of personal decisions and criminal acts should not be thought of as two sides of the same coin. The implications of particular moral or political norms are likely to be different in these two legal contexts, and this may justify asymmetries in the relevant standards for legal capacity. However, the analysis highlights a fundamental question about how much weight moral or political considerations should be given in setting these standards, and this is used to frame a challenge to those calling for significantly wider recognition of the legal capacity of people with mental disabilities on the basis of the Convention. PMID:25997381

  2. AlGaN/GaN heterostructures with an AlGaN layer grown directly on reactive-ion-etched GaN showing a high electron mobility (>1300 cm2 V-1 s-1)

    NASA Astrophysics Data System (ADS)

    Yamamoto, Akio; Makino, Shinya; Kanatani, Keito; Kuzuhara, Masaaki

    2018-04-01

    In this study, the metal-organic-vapor-phase-epitaxial growth behavior and electrical properties of AlGaN/GaN structures prepared by the growth of an AlGaN layer on a reactive-ion-etched (RIE) GaN surface without regrown GaN layers were investigated. The annealing of RIE-GaN surfaces in NH3 + H2 atmosphere, employed immediately before AlGaN growth, was a key process in obtaining a clean GaN surface for AlGaN growth, that is, in obtaining an electron mobility as high as 1350 cm2 V-1 s-1 in a fabricated AlGaN/RIE-GaN structure. High-electron-mobility transistors (HEMTs) were successfully fabricated with AlGaN/RIE-GaN wafers. With decreasing density of dotlike defects observed on the surfaces of AlGaN/RIE-GaN wafers, both two-dimensional electron gas properties of AlGaN/RIE-GaN structures and DC characteristics of HEMTs were markedly improved. Since dotlike defect density was markedly dependent on RIE lot, rather than on growth lot, surface contaminations of GaN during RIE were believed to be responsible for the formation of dotlike defects and, therefore, for the inferior electrical properties.

  3. Making it safe, making it legal, and creating peace of mind.

    PubMed

    Strom, D J

    2001-11-01

    The job of a medical or academic radiation safety officer has three parts: keeping it safe, keeping it legal, and helping people feel that they are safe. Absence of peace-of-mind about radiation protection matters can create very real health effects, even when there is little or no radiation exposure involved. Frightened people may make decisions such as changing jobs (and losing health insurance), terminating a pregnancy, or moving, all of which impact health. Furthermore, frightened people who choose to stick with it may suffer from anxiety, stress, insomnia, and weight loss or even weight gain. Genuinely listening to the concerns of those who benefit from radiation safety services can help to provide peace-of-mind and minimize decisions that are risky to health.

  4. Proximity Effects of Beryllium-Doped GaN Buffer Layers on the Electronic Properties of Epitaxial AlGaN/GaN Heterostructures

    DTIC Science & Technology

    2010-05-17

    arranged by Prof. A. Zaslavsky Keywords: Gallium nitride High electron mobility transistor Molecular beam epitaxy Homoepitaxy Doping a b s t r a c t AlGaN...GaN/Be:GaN heterostructures have been grown by rf-plasma molecular beam epitaxy on free- standing semi-insulating GaN substrates, employing...hydride vapor phase epitaxy (HVPE) grown GaN sub- strates has enabled the growth by molecular beam epitaxy (MBE) of AlGaN/GaNHEMTswith significantly

  5. GaSbBi/GaSb quantum-well and wire laser diodes

    NASA Astrophysics Data System (ADS)

    Ridene, Said

    2018-06-01

    In this work, we present detailed theoretical studies of the optical gain spectra and the emission wavelength of GaSb1-xBix/GaSb and traditional GaAs1-xBix/GaAs dilute-bismide quantum wells and wires (QWs, QWRs) focusing on comparison between their performances. It is found that the optical gain and the emission wavelength of the GaSb-based QW and QWRs lasers would be considerably greater than that of the GaAs-based QW lasers and QWRs for the same QW-, QWR-width, Bi-content and carrier density. The theoretical results were found to be in good agreement with available experimental data, especially for the emission wavelength given by GaSb-based QW laser diodes.

  6. Normally-off p-GaN/AlGaN/GaN high electron mobility transistors using hydrogen plasma treatment

    NASA Astrophysics Data System (ADS)

    Hao, Ronghui; Fu, Kai; Yu, Guohao; Li, Weiyi; Yuan, Jie; Song, Liang; Zhang, Zhili; Sun, Shichuang; Li, Xiajun; Cai, Yong; Zhang, Xinping; Zhang, Baoshun

    2016-10-01

    In this letter, we report a method by introducing hydrogen plasma treatment to realize normally-off p-GaN/AlGaN/GaN HEMT devices. Instead of using etching technology, hydrogen plasma was adopted to compensate holes in the p-GaN above the two dimensional electron gas (2DEG) channel to release electrons in the 2DEG channel and form high-resistivity area to reduce leakage current and increase gate control capability. The fabricated p-GaN/AlGaN/GaN HEMT exhibits normally-off operation with a threshold voltage of 1.75 V, a subthreshold swing of 90 mV/dec, a maximum transconductance of 73.1 mS/mm, an ON/OFF ratio of 1 × 107, a breakdown voltage of 393 V, and a maximum drain current density of 188 mA/mm at a gate bias of 6 V. The comparison of the two processes of hydrogen plasma treatment and p-GaN etching has also been made in this work.

  7. 14 CFR 77.47 - Legal officer.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Legal officer. 77.47 Section 77.47... § 77.47 Legal officer. The Chief Counsel designates a member of his staff to serve as legal officer at each hearing under this subpart. The legal officer may examine witnesses and assist and advise the...

  8. 40 CFR 60.26 - Legal authority.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Legal authority. 60.26 Section 60.26... Legal authority. (a) Each plan shall show that the State has legal authority to carry out the plan... designated pollutant(s) for which the plan is submitted. (c) The plan shall show that the legal authorities...

  9. 40 CFR 60.26 - Legal authority.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Legal authority. 60.26 Section 60.26... Legal authority. (a) Each plan shall show that the State has legal authority to carry out the plan... designated pollutant(s) for which the plan is submitted. (c) The plan shall show that the legal authorities...

  10. 40 CFR 60.26 - Legal authority.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Legal authority. 60.26 Section 60.26... Legal authority. (a) Each plan shall show that the State has legal authority to carry out the plan... designated pollutant(s) for which the plan is submitted. (c) The plan shall show that the legal authorities...

  11. 40 CFR 60.26 - Legal authority.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Legal authority. 60.26 Section 60.26... Legal authority. (a) Each plan shall show that the State has legal authority to carry out the plan... designated pollutant(s) for which the plan is submitted. (c) The plan shall show that the legal authorities...

  12. 40 CFR 60.26 - Legal authority.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Legal authority. 60.26 Section 60.26... Legal authority. (a) Each plan shall show that the State has legal authority to carry out the plan... designated pollutant(s) for which the plan is submitted. (c) The plan shall show that the legal authorities...

  13. Stellar laboratories. IV. New Ga iv, Ga v, and Ga vi oscillator strengths and the gallium abundance in the hot white dwarfs G191-B2B and RE 0503-289

    NASA Astrophysics Data System (ADS)

    Rauch, T.; Werner, K.; Quinet, P.; Kruk, J. W.

    2015-05-01

    Context. For the spectral analysis of high-resolution and high-signal-to-noise (S/N) spectra of hot stars, advanced non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These atmospheres are strongly dependent on the reliability of the atomic data that are used to calculate them. Aims: Reliable Ga iv-vi oscillator strengths are used to identify Ga lines in the spectra of the DA-type white dwarf G191-B2B and the DO-type white dwarf RE 0503-289 and to determine their photospheric Ga abundances. Methods: We newly calculated Ga iv-vi oscillator strengths to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for analyzing of Ga lines exhibited in high-resolution and high-S/N UV observations of G191-B2B and RE 0503-289. Results: We unambiguously detected 20 isolated and 6 blended (with lines of other species) Ga v lines in the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of RE 0503-289. The identification of Ga iv and Ga vi lines is uncertain because they are weak and partly blended by other lines. The determined Ga abundance is 3.5 ± 0.5 × 10-5 (mass fraction, about 625 times the solar value). The Ga iv/Ga v ionization equilibrium, which is a very sensitive indicator for the effective temperature, is well reproduced in RE 0503-289. We identified the strongest Ga iv lines (at 1258.801, 1338.129 Å) in the HST/STIS spectrum of G191-B2B and measured a Ga abundance of 2.0 ± 0.5 × 10-6 (about 22 times solar). Conclusions: Reliable measurements and calculations of atomic data are a prerequisite for stellar-atmosphere modeling. The observed Ga iv-v line profiles in two white dwarf (G191-B2B and RE 0503-289) ultraviolet spectra were well reproduced with our newly calculated oscillator strengths. For the first time, this allowed us to determine the photospheric Ga abundance in white dwarfs. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space

  14. 44 CFR 206.164 - Disaster legal services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Disaster legal services. 206... § 206.164 Disaster legal services. (a) Legal services, including legal advice, counseling, and... adequate legal services, whether the insufficiency existed prior to or results from the major disaster. In...

  15. 44 CFR 206.164 - Disaster legal services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Disaster legal services. 206... § 206.164 Disaster legal services. (a) Legal services, including legal advice, counseling, and... adequate legal services, whether the insufficiency existed prior to or results from the major disaster. In...

  16. 44 CFR 206.164 - Disaster legal services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Disaster legal services. 206... § 206.164 Disaster legal services. (a) Legal services, including legal advice, counseling, and... adequate legal services, whether the insufficiency existed prior to or results from the major disaster. In...

  17. Effect of an InxGa1-xAs-GaAs blocking heterocathode metal contact on the GaAs TED operation

    NASA Astrophysics Data System (ADS)

    Arkusha, Yu. V.; Prokhorov, E. D.; Storozhenko, I. P.

    2004-09-01

    The frequency dependence of the generation efficiency of an mm- -nn:In:InxGaGa1-1-xAs- As-nn:GaAs-:GaAs-nn++:GaAs TED with the 2.5-mm long active region is calculated. The optimum values - which yield the diode maximum generation efficiency - for the :GaAs TED with the 2.5-mm long active region is calculated. The optimum values - which yield the diode maximum generation efficiency - for the nn:In:InxGaGa1-1-xAs cathode length, the cathode concentration of ionized impurities, and the height of the potential barrier on metal contact are determined.As cathode length, the cathode concentration of ionized impurities, and the height of the potential barrier on metal contact are determined.

  18. Optimal MRI sequences for 68Ga-PSMA-11 PET/MRI in evaluation of biochemically recurrent prostate cancer.

    PubMed

    Lake, Spencer T; Greene, Kirsten L; Westphalen, Antonio C; Behr, Spencer C; Zagoria, Ronald; Small, Eric J; Carroll, Peter R; Hope, Thomas A

    2017-09-19

    PET/MRI can be used for the detection of disease in biochemical recurrence (BCR) patients imaged with 68 Ga-PSMA-11 PET. This study was designed to determine the optimal MRI sequences to localize positive findings on 68 Ga-PSMA-11 PET of patients with BCR after definitive therapy. Fifty-five consecutive prostate cancer patients with BCR imaged with 68 Ga-PSMA-11 3.0T PET/MRI were retrospectively analyzed. Mean PSA was 7.9 ± 12.9 ng/ml, and mean PSA doubling time was 7.1 ± 6.6 months. Detection rates of anatomic correlates for prostate-specific membrane antigen (PSMA)-positive foci were evaluated on small field of view (FOV) T2, T1 post-contrast, and diffusion-weighted images. For prostate bed recurrences, the detection rate of dynamic contrast-enhanced (DCE) imaging for PSMA-positive foci was evaluated. Finally, the detection sensitivity for PSMA-avid foci on 3- and 8-min PET acquisitions was compared. PSMA-positive foci were detected in 89.1% (49/55) of patients evaluated. Small FOV T2 performed best for lymph nodes and detected correlates for all PSMA-avid lymph nodes. DCE imaging performed the best for suspected prostate bed recurrence, detecting correlates for 87.5% (14/16) of PSMA-positive prostate bed foci. The 8-min PET acquisition performed better than the 3-min acquisition for lymph nodes smaller than 1 cm, detecting 100% (57/57) of lymph nodes less than 1 cm, compared to 78.9% (45/57) for the 3-min acquisition. PSMA PET/MRI performed well for the detection of sites of suspected recurrent disease in patients with BCR. Of the MRI sequences obtained for localization, small FOV T2 images detected the greatest proportion of PSMA-positive abdominopelvic lymph nodes and DCE imaging detected the greatest proportion of PSMA-positive prostate bed foci. The 8-min PET acquisition was superior to the 3 min acquisition for detection of small lymph nodes.

  19. InGaAsSb/AlGaAsSb Heterojunction Phototransistors for Infrared Applications

    NASA Technical Reports Server (NTRS)

    Refaat, Tamer F.; Abedin, M. N.; Sulima, Oleg V.; Ismail, Syed; Singh, Upendra N.

    2006-01-01

    High quality infrared (IR) quantum detectors are important for several applications, such as atmospheric remote sensing, chemical detection and absorption spectroscopy. Although several IR detectors are commercially available, with different materials and structures, they provide limited performance regarding the signal-to-noise ratio and the corresponding minimum detectable signal. InGaAsSb/AlGaAsSb heterojunction based phototransistors show strong potential for developing IR sensors with improved performance. In this paper, the performance of a novel npn InGaAsSb/AlGaAsSb heterojunction phototransistor is presented. This performance study is based on experimental characterization of the device dark current, noise and spectral response. Detectivity of 1.7x10(exp 9) cmHz(exp 1/2)/W at 2 microns was obtained at 100 C temperature and 2 V bias voltage. This corresponds to a responsivity of 94.7 A/W and an internal gain of 156 with about 37.7% quantum efficiency. Reducing the temperature to -30 C allows to increase the bias to 3V and enhance the detectivity to 8.7x10(exp 10) cmHz(exp 1/2)/W at the same wavelength, which corresponds to a responsivity of 386.5 A/W and an internal gain of 288.2 with about 83.3% quantum efficiency. The device impulse response and linearity, including the corresponding dynamic range, also are presented. Impulse response analysis indicated a settling time of about 1.1 s at 2V and 100 C, while linearity measurements indicated a constant responsivity in the radiation intensity range of 1.6x10(exp -7) W/sq cm and 31.6 mW/sq cm.

  20. The changing purpose of mental health law: From medicalism to legalism to new legalism.

    PubMed

    Brown, Jennifer

    2016-01-01

    The role of law in regulating mental health detention has come to engender great contention in the legal and sociological disciplines alike. This conflict is multifaceted but is centred upon the extent to which law should control the psychiatric power of detention. In this manner the evolution of law regulating mental health detention has been seen in terms of a pendulous movement between two extremes of medicalism and legalism. Drawing on socio-legal literature, legislation, international treaties and case law this article examines the changing purpose of mental health law from an English and Council of Europe perspective by utilizing the concepts of medicalism, legalism and new legalism as descriptive devices before arguing that the UN Convention on the Rights of Persons with Disabilities goes further than all of these concepts and has the potential to influence mental health laws internationally. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Strain-compensated (Ga,In)N/(Al,Ga)N/GaN multiple quantum wells for improved yellow/amber light emission

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

    Lekhal, K.; Damilano, B., E-mail: bd@crhea.cnrs.fr; De Mierry, P.

    2015-04-06

    Yellow/amber (570–600 nm) emitting In{sub x}Ga{sub 1−x}N/Al{sub y}Ga{sub 1−y}N/GaN multiple quantum wells (QWs) have been grown by metal organic chemical vapor deposition on GaN-on- sapphire templates. When the (Al,Ga)N thickness of the barrier increases, the room temperature photoluminescence is red-shifted while its yield increases. This is attributed to an increase of the QW internal electric field and an improvement of the material quality due to the compensation of the compressive strain of the In{sub x}Ga{sub 1−x}N QWs by the Al{sub y}Ga{sub 1−y}N layers, respectively.

  2. 42 CFR 425.104 - Legal entity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Legal entity. 425.104 Section 425.104 Public Health....104 Legal entity. (a) An ACO must be a legal entity, formed under applicable State, Federal, or Tribal... in this part. (b) An ACO formed by two or more otherwise independent ACO participants must be a legal...

  3. 42 CFR 425.104 - Legal entity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Legal entity. 425.104 Section 425.104 Public Health....104 Legal entity. (a) An ACO must be a legal entity, formed under applicable State, Federal, or Tribal... in this part. (b) An ACO formed by two or more otherwise independent ACO participants must be a legal...

  4. 42 CFR 425.104 - Legal entity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Legal entity. 425.104 Section 425.104 Public Health....104 Legal entity. (a) An ACO must be a legal entity, formed under applicable State, Federal, or Tribal... in this part. (b) An ACO formed by two or more otherwise independent ACO participants must be a legal...

  5. Legal Typewriting, Business Education: 7705.35.

    ERIC Educational Resources Information Center

    Missirlian, Melanie

    The course is designed to help the student qualify for employment as a typist in a legal office. Instruction is given to enable the student to prepare all types of legal documents, spell and use legal terminology correctly, and transfer legal information from one document to another. The course description includes: (1) equipment and supplies, (2)…

  6. Titanium induced polarity inversion in ordered (In,Ga)N/GaN nanocolumns.

    PubMed

    Kong, X; Li, H; Albert, S; Bengoechea-Encabo, A; Sanchez-Garcia, M A; Calleja, E; Draxl, C; Trampert, A

    2016-02-12

    We report on the formation of polarity inversion in ordered (In,Ga)N/GaN nanocolumns grown on a Ti-masked GaN-buffered sapphire substrate by plasma assisted molecular beam epitaxy. High-resolution transmission electron microscopy and electron energy-loss spectroscopy reveal a stacking fault-like planar defect at the homoepitaxial GaN interface due to Ti incorporation, triggering the generation of N-polar domains in Ga-polar nanocolumns. Density functional theory calculations are applied to clarify the atomic configurations of a Ti monolayer occupation on the GaN (0002) plane and to prove the inversion effect. The polarity inversion leads to an enhanced indium incorporation in the subsequent (In,Ga)N segment of the nanocolumn. This study provides a deeper understanding of the effects of Ti mask in the well-controlled selective area growth of (In,Ga)N/GaN nanocolumns.

  7. Thermal quenching of the yellow luminescence in GaN

    NASA Astrophysics Data System (ADS)

    Reshchikov, M. A.; Albarakati, N. M.; Monavarian, M.; Avrutin, V.; Morkoç, H.

    2018-04-01

    We observed varying thermal quenching behavior of the yellow luminescence band near 2.2 eV in different GaN samples. In spite of the different behavior, the yellow band in all the samples is caused by the same defect—the YL1 center. In conductive n-type GaN, the YL1 band quenches with exponential law, and the Arrhenius plot reveals an ionization energy of ˜0.9 eV for the YL1 center. In semi-insulating GaN, an abrupt and tunable quenching of the YL1 band is observed, where the apparent activation energy in the Arrhenius plot is not related to the ionization energy of the defect. In this case, the ionization energy can be found by analyzing the shift of the characteristic temperature of PL quenching with excitation intensity. We conclude that only one defect, namely, the YL1 center, is responsible for the yellow band in undoped and doped GaN samples grown by different techniques.

  8. MOVPE growth of Ga(PBi) on GaP and GaP on Si with Bi fractions up to 8%

    NASA Astrophysics Data System (ADS)

    Nattermann, L.; Beyer, A.; Ludewig, P.; Hepp, T.; Sterzer, E.; Volz, K.

    2017-04-01

    Dilute bismide containing materials can play an important role in addressing the issue of finding new highly efficient lasers for telecommunications as well as sensing applications. In the last several years a growing body of literature has emerged, particularly on the growth of Ga(AsBi). However, the metal organic vapor phase epitaxy growth of Ga(AsBi) with high amounts of Bi, which are necessary to overcome Auger recombination and reach telecommunications wavelengths, still remains a challenge. Ga(PBi) could be a promising alternative, but has not been deposited with significant amounts of Bi so far. A second argument for Ga(PBi) is that it could be grown on GaP, which was already deposited on Si. A number of researchers have reported theoretical calculations on the band structure of Ga(PBi), but experimental results are still lacking. In this work we present the first Ga(PBi) structures, grown by metal organic vapor phase epitaxy on GaP and on GaP on Si. By careful characterization with high resolution X-ray diffraction, atomic force microscopy, secondary ion mass spectrometry and scanning transmission electron microscopy, we will show that we have realized high quality Ga(PBi) with Bi fractions over 8%.

  9. Cluster analysis of the national weight control registry to identify distinct subgroups maintaining successful weight loss.

    PubMed

    Ogden, Lorraine G; Stroebele, Nanette; Wyatt, Holly R; Catenacci, Victoria A; Peters, John C; Stuht, Jennifer; Wing, Rena R; Hill, James O

    2012-10-01

    The National Weight Control Registry (NWCR) is the largest ongoing study of individuals successful at maintaining weight loss; the registry enrolls individuals maintaining a weight loss of at least 13.6 kg (30 lb) for a minimum of 1 year. The current report uses multivariate latent class cluster analysis to identify unique clusters of individuals within the NWCR that have distinct experiences, strategies, and attitudes with respect to weight loss and weight loss maintenance. The cluster analysis considers weight and health history, weight control behaviors and strategies, effort and satisfaction with maintaining weight, and psychological and demographic characteristics. The analysis includes 2,228 participants enrolled between 1998 and 2002. Cluster 1 (50.5%) represents a weight-stable, healthy, exercise conscious group who are very satisfied with their current weight. Cluster 2 (26.9%) has continuously struggled with weight since childhood; they rely on the greatest number of resources and strategies to lose and maintain weight, and report higher levels of stress and depression. Cluster 3 (12.7%) represents a group successful at weight reduction on the first attempt; they were least likely to be overweight as children, are maintaining the longest duration of weight loss, and report the least difficulty maintaining weight. Cluster 4 (9.9%) represents a group less likely to use exercise to control weight; they tend to be older, eat fewer meals, and report more health problems. Further exploration of the unique characteristics of these clusters could be useful for tailoring future weight loss and weight maintenance programs to the specific characteristics of an individual.

  10. 28 CFR 543.15 - Legal aid program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Legal aid program. 543.15 Section 543.15 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.15 Legal aid program. (a) A legal aid program which is funded or approved...

  11. 28 CFR 543.15 - Legal aid program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Legal aid program. 543.15 Section 543.15 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.15 Legal aid program. (a) A legal aid program which is funded or approved...

  12. 28 CFR 543.15 - Legal aid program.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Legal aid program. 543.15 Section 543.15 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.15 Legal aid program. (a) A legal aid program which is funded or approved...

  13. 28 CFR 543.15 - Legal aid program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Legal aid program. 543.15 Section 543.15 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.15 Legal aid program. (a) A legal aid program which is funded or approved...

  14. 28 CFR 543.15 - Legal aid program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Legal aid program. 543.15 Section 543.15 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT LEGAL MATTERS Inmate Legal Activities § 543.15 Legal aid program. (a) A legal aid program which is funded or approved...

  15. A hole modulator for InGaN/GaN light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Zhang, Zi-Hui; Kyaw, Zabu; Liu, Wei; Ji, Yun; Wang, Liancheng; Tan, Swee Tiam; Sun, Xiao Wei; Demir, Hilmi Volkan

    2015-02-01

    The low p-type doping efficiency of the p-GaN layer has severely limited the performance of InGaN/GaN light-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active region. The essence of improving the hole injection efficiency is to increase the hole concentration in the p-GaN layer. Therefore, in this work, we have proposed a hole modulator and studied it both theoretically and experimentally. In the hole modulator, the holes in a remote p-type doped layer are depleted by the built-in electric field and stored in the p-GaN layer. By this means, the overall hole concentration in the p-GaN layer can be enhanced. Furthermore, the hole modulator is adopted in the InGaN/GaN LEDs, which reduces the effective valance band barrier height for the p-type electron blocking layer from ˜332 meV to ˜294 meV at 80 A/cm2 and demonstrates an improved optical performance, thanks to the increased hole concentration in the p-GaN layer and thus the improved hole injection into the MQWs.

  16. Ga originated kink-and-tail Zn diffusion profiles in InGaAsP and InGaAlAs alloys during MOVPE regrowth

    NASA Astrophysics Data System (ADS)

    Kitatani, T.; Okamoto, K.; Uchida, K.; Tanaka, S.

    2017-12-01

    We investigated the diffusion characteristics of Zn in ternary and quaternary alloys of InGaAsP and InGaAlAs, which are important materials in long-wavelength optical communication devices. The measured Zn diffusion profiles of InGaAs, InGaAsP, and InGaAlAs showed kink-and-tail shapes in which Zn concentration fell abruptly at first and then decreased slowly, whereas those of InP and InAlAs showed only abrupt decreases. Thus, only Ga-containing alloys had tail-like profiles. Since this tail was well described by the group-V vacancy related defect model, we deduced that its mechanism is closely related with group-V vacancies in Ga-related bonds such as GaP or GaAs. Furthermore, we demonstrated the possibility that many more group-V vacancies originated from GaP bonds than from GaAs bonds, indicating the difficulty in crystal growth of high quality alloys that have GaP components.

  17. Comparison of 68Ga-PSMA PET/CT and multiparametric MRI for staging of high-risk prostate cancer68Ga-PSMA PET and MRI in prostate cancer.

    PubMed

    Tulsyan, Shruti; Das, Chandan J; Tripathi, Madhavi; Seth, Amlesh; Kumar, Rajeev; Bal, Chandrasekhar

    2017-12-01

    We carried out this study to compare Glu-NH-CO-NH-Lys-(Ahx) [Ga(HBED-CC)] [Ga prostate-specific membrane antigen-11 (PSMA-11)] PET with multiparametric MRI (mpMRI) for the staging of high-risk prostate cancer. This was a prospective study in which 36 patients with high-risk prostate cancer were included. The criteria for inclusion were biopsy-proven prostate cancer with a serum prostate specific antigen of at least 20 and/or Gleason's score of at least 8. Each patient then underwent both gallium-68 (Ga)-PSMA PET/computed tomography (CT) and mpMRI including diffusion-weighted whole-body imaging with background body signal suppression within an interval of 1 week and both modalities were compared for staging of primary disease, lymph node, and distant metastasis. The median age of the 36 patients included was 65 years (range: 44-80 years) and the median prostate specific antigen was 94.3 ng/ml (range: 20-19005  ng/ml). Concordance for localization of primary on Ga-PSMA PET/CT and MRI was observed in 19/36 (52.7%) patients. Concurrence for T staging on Ga-PSMA and MRI was observed in 58.3% of patients. Ga-PSMA PET/CT detected higher numbers of patients with regional (29) and nonregional (15) lymph nodes in comparison with MRI (20 and 5, respectively). Concurrence for regional and nonregional lymph node staging was observed in 72.2% of patients. Additional sites of metastatic disease reported on Ga-PSMA PET/CT were to the skeleton in one patient, the lung in two patients, and the liver in one patient. This study suggests that Ga-PSMA PET/CT is useful for lymph node and metastases staging in high-risk prostate cancers, whereas its utility for staging of disease in the prostate is limited.

  18. Short-wave infrared barriode detectors using InGaAsSb absorption material lattice matched to GaSb

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

    Craig, A. P.; Percy, B.; Marshall, A. R. J.

    2015-05-18

    Short-wave infrared barriode detectors were grown by molecular beam epitaxy. An absorption layer composition of In{sub 0.28}Ga{sub 0.72}As{sub 0.25}Sb{sub 0.75} allowed for lattice matching to GaSb and cut-off wavelengths of 2.9 μm at 250 K and 3.0 μm at room temperature. Arrhenius plots of the dark current density showed diffusion limited dark currents approaching those expected for optimized HgCdTe-based detectors. Specific detectivity figures of around 7×10{sup 10} Jones and 1×10{sup 10} Jones were calculated, for 240 K and room temperature, respectively. Significantly, these devices could support focal plane arrays working at higher operating temperatures.

  19. Semiquantitative analysis and characterization of physiological biodistribution of (68)Ga-DOTA-TATE PET/CT.

    PubMed

    Kunikowska, Jolanta; Królicki, Leszek; Pawlak, Dariusz; Zerizer, Imene; Mikołajczak, Renata

    2012-11-01

    The aim of this study was to describe the normal physiological distribution of (68)Ga-DOTA-TATE using the SUV to reflect the density of somatostatin receptors in various organ systems. A total of 250 patients (90 men and 160 women) were imaged on a Biograph 64 PET/CT TruePoint (Siemens Medical Solutions) 60 to 80 minutes after injection of 120 to 200 MBq (3.2-5.4 mCi) of (68)Ga-DOTA-TATE. Visual assessment was performed on all studies on the multimodality workstation, and sites of increased uptake were recorded. The SUVmax was also calculated for each organ demonstrating increased (68)Ga-DOTA-TATE uptake. Visual assessment of the (68)Ga-DOTA-TATE PET/CT studies revealed increased uptake in the pituitary, salivary, thyroid glands, liver, spleen, adrenals, kidneys and bone reflecting normal increased somatostatin receptor expression. These sites were confirmed to be disease free on clinical follow-up and on correlation with other imaging (CT/MRI/ultrasound). Using semiquantitative analysis, SUVmax values were the highest in the pituitary gland [11 (4.5)], spleen [18.9 (6.6)], adrenal [14.0 (5.6)], and kidneys [14.2 (3.6)]. In addition, increasing uptake in the uncinate process of pancreas was noted in 12% of patients with SUVmax of 9.2 (3.3). Moderate (68)Ga-DOTA-TATE uptake was also present in salivary gland [3.4 (1.8)], thyroid [2.9 (1.2)], and normal liver [6.5 (2.2)]. The bones generally showed low (68)Ga-DOTA-TATE uptake with an SUVmax of 1.0 (0.3). Knowledge of the normal (68)Ga-DOTA-TATE distribution is highly important for accurate interpretation of this novel imaging modality, which is increasingly being used in the imaging of neuroendocrine tumor.

  20. Same-Sex Couples: Legal Complexities

    ERIC Educational Resources Information Center

    Oswald, Ramona Faith; Kuvalanka, Katherine A.

    2008-01-01

    In this article, the authors present a typology for organizing our current knowledge regarding same-sex couples in the United States who have and have not established legal ties between partners. This framework is complemented by a discussion of key rulings that define what is legally possible as well as the introduction of "legal consciousness,"…

  1. A Metallurgical Study of Nāga Bhasma

    PubMed Central

    Singh Gautam, Dev Nath

    2017-01-01

    Background: The metal Nāga (Lead) is being used by Indians since ancient times. Its external and internal uses have been described in Caraka, Suśruta and other Ayurvedic Saṃhitā. According to most of the Rasa texts, Nāga Bhasma and its formulations are used in many diseases such as Prameha, Jvara, Gulma, Śukrameha etc. Objectives: In the present study, Nāga Bhasma was prepared by the traditional Puṭa method (TPM) and by the electric muffle furnace Puṭa method (EMFPM) and standardized using Metallographic studies. Doing so helps in the study of the microstructure of Nāga Bhasma and also helps in the identification of the metal particles along with the nature of compound formed during the Māraṇa (Bhasmīkaraṇa) process. Setting and Design: Different samples from initial raw material to final product of Nāga Bhasma were collected during the pharmaceutical process (1st, 30th and 60th Puṭa) from both methods i.e. TPM and EMFPM. Samples from both methods were studied using metallographic examination. Materials and Methods: The processing of the Nāga Bhasma (ṣaṣṭipuṭa) was done according to Ānanda Kanda[9] Samples from the raw material i.e. Aśodhita Nāga (raw Lead) and that processed after 1st, 30th and 60th Puṭa from both methods i.e. traditional Puṭa method (using heat from burning of cow dung cakes) and electric muffle furnace Puṭa method were taken. They were mounted on self hardening acrylic base. After careful polishing to obtain scratch free surface of product, they were used for metallurgical study. Conclusion: This study shows that traditional Puṭa method may be better than electric muffle furnace Puṭa method because of more homogeneous distribution of Lead sulphide in the Nāga Bhasma which is prepared by traditional method. PMID:29269968

  2. Medical-legal issues in Charcot's neurologic career.

    PubMed

    Goetz, Christopher G

    2004-05-25

    Trace the medical-legal involvement of the 19th century clinical neurologist Jean-Martin Charcot. The two major neurologic concerns of the 1800s that involved legal questions were topics of particular academic interest to Charcot: post-traumatic neurologic syndromes and the behavioral consequences of hysteria and hypnotism. Although Charcot's medical views influenced several nonmedical fields, including art, poetry, and drama, his impact on medical-legal issues has not been examined. Original documents from the Bibliothèque Charcot at the Salpêtrière Hospital in Paris, legal documents, and publications from Charcot's era were examined. Although his involvement in medical-legal affairs was a modest element of Charcot's multifaceted career, he was involved in four different types of medical-legal activities: as a cited authority in the medical-legal literature, as an author of articles within medical-legal contexts, as a subpoenaed expert consultant, and as an expert examiner. Charcot's involvement demonstrates the long tradition of an interface between neurology and legal medicine and provides a model for highly limited but authoritative involvement by academic neurologists in medical-legal affairs.

  3. Improving the Care of Youth With Type 1 Diabetes With a Novel Medical-Legal Community Intervention: The Diabetes Community Care Ambassador Program.

    PubMed

    Malik, Faisal S; Yi-Frazier, Joyce P; Taplin, Craig E; Roth, Christian L; Whitlock, Kathryn B; Howard, Waylon; Pihoker, Catherine

    2018-04-01

    Purpose The purpose of this study was to examine the feasibility and efficacy of the Diabetes Community Care Ambassador (DCCA) Program, a novel medical-legal community intervention designed to support high-risk youth with type 1 diabetes. Methods Study eligibility criteria: ages 3-19 years, A1C ≥8.5% (≥69 mmol/mol) and/or recent diabetic ketoacidosis hospitalization, type 1 diabetes duration ≥1 year, and English- or Spanish-speaking. Eighty-nine youth and their caregivers participated in the 9- to 12-month intervention, which included diabetes education and support through 3 home visits, 1 to 2 school visits, and phone support from a lay health worker, as well as legal support from a medical-legal partnership attorney. Feasibility was assessed; change in A1C was compared in a linear mixed model. Results Of the 89 DCCA Program participants, 80% completed the program, with the majority of participants rating their DCCA favorably. Sixty-two percent reported ≥1 unmet legal need, of whom 29% accepted legal counsel. Youth enrolled in the DCCA Program demonstrated an improvement in glycemic control as their mean A1C decreased from 9.71% (83 mmol/mol) at the start of the program to 9.40% (79 mmol/mol) at the end of the intervention period ( P = .03). Participants with public health insurance experienced the greatest differential A1C reduction (9.79% to 9.11%, 83 mmol/mol to 76 mmol/mol). Conclusions The DCCA Program represents a promising intervention for improving care of high-risk youth with type 1 diabetes. A significant proportion of caregivers of youth reported having an unmet legal need. Participants remained highly engaged and demonstrated improved glycemic control, particularly youth with public health insurance.

  4. Enhanced thermoelectric transport in modulation-doped GaN/AlGaN core/shell nanowires.

    PubMed

    Song, Erdong; Li, Qiming; Swartzentruber, Brian; Pan, Wei; Wang, George T; Martinez, Julio A

    2016-01-08

    The thermoelectric properties of unintentionally n-doped core GaN/AlGaN core/shell N-face nanowires are reported. We found that the temperature dependence of the electrical conductivity is consistent with thermally activated carriers with two distinctive donor energies. The Seebeck coefficient of GaN/AlGaN nanowires is more than twice as large as that for the GaN nanowires alone. However, an outer layer of GaN deposited onto the GaN/AlGaN core/shell nanowires decreases the Seebeck coefficient at room temperature, while the temperature dependence of the electrical conductivity remains the same. We attribute these observations to the formation of an electron gas channel within the heavily-doped GaN core of the GaN/AlGaN nanowires. The room-temperature thermoelectric power factor for the GaN/AlGaN nanowires can be four times higher than the GaN nanowires. Selective doping in bandgap engineered core/shell nanowires is proposed for enhancing the thermoelectric power.

  5. Early Petrogenesis and Late Impact(?) Metamorphism on the GRA 06128/9 Parent Body

    NASA Technical Reports Server (NTRS)

    Nyquist, Laurence E.; Shih, C.-Y.; Reese, Y. D.

    2009-01-01

    Initial studies of GRA06128 and GRA06129 (hereafter GRA 8 and GRA 9) suggested that these alkalic meteorites represent partial melts of a parent body of approximately chondritic composition. A SM-147-Nd-143 isochron age of 4.545 +/- 0.087 Ga was found for GRA 8, but plagioclase (oligoclase) plus whole rock and leachate samples gave an apparent secondary age of approximately 3.5 Ga. The approximately 4.54 Ga age was interpreted to be the crystallization age of GRA 8; the approximately 3.5 Ga as an upper limit to a time of metamorphism. Here we extend Sm-Nd and Rb-Sr analyses to GRA 9.

  6. AlGaN/GaN field effect transistors for power electronics—Effect of finite GaN layer thickness on thermal characteristics

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

    Hodges, C., E-mail: chris.hodges@bristol.ac.uk; Anaya Calvo, J.; Kuball, M.

    2013-11-11

    AlGaN/GaN heterostructure field effect transistors with a 150 nm thick GaN channel within stacked Al{sub x}Ga{sub 1−x}N layers were investigated using Raman thermography. By fitting a thermal simulation to the measured temperatures, the thermal conductivity of the GaN channel was determined to be 60 W m{sup −1} K{sup −1}, over 50% less than typical GaN epilayers, causing an increased peak channel temperature. This agrees with a nanoscale model. A low thermal conductivity AlGaN buffer means the GaN spreads heat; its properties are important for device thermal characteristics. When designing power devices with thin GaN layers, as well as electrical considerations, the reducedmore » channel thermal conductivity must be considered.« less

  7. Mg doping of GaN grown by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Meng; Bhattacharya, Pallab; Guo, Wei; Banerjee, Animesh

    2010-03-01

    Acceptor doping of GaN with Mg during plasma-assisted molecular beam epitaxy, under N-rich conditions and a relatively high growth temperature of 740 °C, was investigated. The p-doping level steadily increases with increasing Mg flux. The highest doping level achieved, determined from Hall measurements, is 2.1×1018 cm-3. The corresponding doping efficiency and hole mobility are ˜4.9% and 3.7 cm2/V s at room temperature. Cross-sectional transmission electron microscopy and photoluminescence measurements confirm good crystalline and optical quality of the Mg-doped layers. An InGaN/GaN quantum dot light emitting diode (λpeak=529 nm) with p-GaN contact layers grown under N-rich condition exhibits a low series resistance of 9.8 Ω.

  8. A hole modulator for InGaN/GaN light-emitting diodes

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

    Zhang, Zi-Hui; Kyaw, Zabu; Liu, Wei

    2015-02-09

    The low p-type doping efficiency of the p-GaN layer has severely limited the performance of InGaN/GaN light-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active region. The essence of improving the hole injection efficiency is to increase the hole concentration in the p-GaN layer. Therefore, in this work, we have proposed a hole modulator and studied it both theoretically and experimentally. In the hole modulator, the holes in a remote p-type doped layer are depleted by the built-in electric field and stored in the p-GaN layer. By this means, the overall holemore » concentration in the p-GaN layer can be enhanced. Furthermore, the hole modulator is adopted in the InGaN/GaN LEDs, which reduces the effective valance band barrier height for the p-type electron blocking layer from ∼332 meV to ∼294 meV at 80 A/cm{sup 2} and demonstrates an improved optical performance, thanks to the increased hole concentration in the p-GaN layer and thus the improved hole injection into the MQWs.« less

  9. Birth weight and infant growth: optimal infant weight gain versus optimal infant weight.

    PubMed

    Xiong, Xu; Wightkin, Joan; Magnus, Jeanette H; Pridjian, Gabriella; Acuna, Juan M; Buekens, Pierre

    2007-01-01

    Infant growth assessment often focuses on "optimal" infant weights and lengths at specific ages, while de-emphasizing infant weight gain. Objective of this study was to examine infant growth patterns by measuring infant weight gain relative to birth weight. We conducted this study based on data collected in a prospective cohort study including 3,302 births with follow up examinations of infants between the ages of 8 and 18 months. All infants were participants in the Louisiana State Women, Infant and Children Supplemental Food Program between 1999 and 2001. Growth was assessed by infant weight gain percentage (IWG%, defined as infant weight gain divided by birth weight) as well as by mean z-scores and percentiles for weight-for-age, length-for-age, and weight-for-length calculated based on growth charts published by the U.S. Centers for Disease Control (CDC). An inverse relationship was noted between birth weight category and IWG% (from 613.9% for infants with birth weights <1500 g to 151.3% for infants with birth weights of 4000 g or more). In contrast, low birth weight infants had lower weight-for-age, weight-for-length z-scores and percentiles compared to normal birth weight infants according to CDC growth charts. Although low birth weight infants had lower anthropometric measures compared to a national reference population, they had significant catch-up growth; High birth weight infants had significant slow-down growth. We suggest that growth assessments should compare infants' anthropometric data to their own previous growth measures as well as to a reference population. Further studies are needed to identify optimal ranges of infant weight gain.

  10. First Principles Electronic Structure of Mn doped GaAs, GaP, and GaN Semiconductors

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

    Schulthess, Thomas C; Temmerman, Walter M; Szotek, Zdzislawa

    We present first-principles electronic structure calculations of Mn doped III-V semiconductors based on the local spin-density approximation (LSDA) as well as the self-interaction corrected local spin density method (SIC-LSD). We find that it is crucial to use a self-interaction free approach to properly describe the electronic ground state. The SIC-LSD calculations predict the proper electronic ground state configuration for Mn in GaAs, GaP, and GaN. Excellent quantitative agreement with experiment is found for magnetic moment and p-d exchange in (GaMn)As. These results allow us to validate commonly used models for magnetic semiconductors. Furthermore, we discuss the delicate problem of extractingmore » binding energies of localized levels from density functional theory calculations. We propose three approaches to take into account final state effects to estimate the binding energies of the Mn-d levels in GaAs. We find good agreement between computed values and estimates from photoemisison experiments.« less

  11. Current-induced switching in CoGa/L10 MnGa/(CoGa)/Pt structure with different thicknesses

    NASA Astrophysics Data System (ADS)

    Ranjbar, R.; Suzuki, K. Z.; Mizukami, S.

    2018-06-01

    In this paper, we present the results of our study into current-induced spin-orbit torque (SOT) switching in perpendicularly magnetized CoGa/MnGa/Pt trilayers with different thicknesses of MnGa and Pt. The SOT switching was observed for all films that undergo Joule heating. We also investigate SOT switching in the bottom (CoGa)/MnGa/top(CoGa/Pt) films with different top layers. Although both the bottom and top layers contribute to the SOT, the relative magnitudes of the switching current densities JC in the top and bottom layers indicate that the SOT is dominant in the top layer. The JC as a function of thickness is discussed in terms of the magnetic properties and resistivity. Experimental data suggested that the MnGa thickness dependence of JC may originate from the perpendicular magnetic anisotropy thickness product Kueff t value. On the other hand, JC as a function of the Pt thickness shows weak dependence. This may be attributed to the slight change of spin-Hall angle θSH value with different thicknesses of Pt, when we assumed that the SOT switching is primarily due to the spin-Hall effect.

  12. Theoretical Modeling of Intensity Noise in InGaN Semiconductor Lasers

    PubMed Central

    2014-01-01

    This paper introduces modeling and simulation of the noise properties of the blue-violet InGaN laser diodes. The noise is described in terms of the spectral properties of the relative intensity noise (RIN). We examine the validity of the present noise modeling by comparing the simulated results with the experimental measurements available in literature. We also compare the obtained noise results with those of AlGaAs lasers. Also, we examine the influence of gain suppression on the quantum RIN. In addition, we examine the changes in the RIN level when describing the gain suppression by the case of inhomogeneous spectral broadening. The results show that RIN of the InGaN laser is nearly 9 dB higher than that of the AlGaAs laser. PMID:25147848

  13. Joint association of birth weight and physical activity/sedentary behavior with obesity in children ages 9-11 years from 12 countries.

    PubMed

    Qiao, Yijuan; Zhang, Tao; Liu, Hongyan; Katzmarzyk, Peter T; Chaput, Jean-Philippe; Fogelholm, Mikael; Johnson, William D; Kuriyan, Rebecca; Kurpad, Anura; Lambert, Estelle V; Maher, Carol; Maia, José A R; Matsudo, Victor; Olds, Timothy; Onywera, Vincent; Sarmiento, Olga L; Standage, Martyn; Tremblay, Mark S; Tudor-Locke, Catrine; Zhao, Pei; Hu, Gang

    2017-06-01

    To examine the joint association of birth weight and physical activity/sedentary time with childhood obesity in 12 countries. A cross-sectional study of 5,088 children aged 9 to 11 years was conducted. Birth weight was recalled by parents or guardians. Moderate-to-vigorous physical activity (MVPA) and sedentary behavior were objectively measured using accelerometry. The association of birth weight with the odds of obesity, central obesity, and high body fat was significant among children with either low MVPA or high sedentary time but not among children with either high MVPA or low sedentary time. In comparison with children with normal birth weight and high MVPA, children with high birth weight and low MVPA showed 4.48- to 5.18-fold higher odds of obesity, central obesity, and high body fat; children with normal birth weight and low MVPA showed 3.00- to 3.30-fold higher odds of obesity, central obesity, and high body fat, and children with high birth weight and high MVPA showed 1.16- to 1.68-fold higher odds of obesity, central obesity, and high body fat. High MVPA is more important than high birth weight as a correlate of obesity in children. © 2017 The Obesity Society.

  14. Joint association of birth weight and physical/sedentary activity with obesity at children ages 9–11 years in 12 countries

    PubMed Central

    Qiao, Yijuan; Zhang, Tao; Liu, Hongyan; Katzmarzyk, Peter T.; Chaput, Jean-Philippe; Fogelholm, Mikael; Johnson, William D.; Kuriyan, Rebecca; Kurpad, Anura; Lambert, Estelle V.; Maher, Carol; Maia, José A.R.; Matsudo, Victor; Olds, Timothy; Onywera, Vincent; Sarmiento, Olga L.; Standage, Martyn; Tremblay, Mark S.; Tudor-Locke, Catrine; Zhao, Pei; Hu, Gang

    2017-01-01

    Objective To examine the joint association of birth weight and physical/sedentary activity time with obesity in 12 countries. Methods A cross-sectional study of 5,088 children aged 9–11 years was conducted. Birth weight was recalled by parents or guardians. Moderate-to-vigorous physical activity (MVPA) and sedentary behavior were objectively measured using accelerometry. Results The association of birth weight with the odds of obesity, central obesity and high body fat was significant among children with either low MVPA or high sedentary time but not among children with either high MVPA or low sedentary time. In comparison with children with normal birth weight and high MVPA, children with high birth weight and low MVPA showed 4.48–5.18 fold higher odds of obesity, central obesity, and high body fat; children with normal birth weight and low MVPA showed 3.00–3.30 fold higher odds of obesity, central obesity, and high body fat, and children with high birth weight and high MVPA showed 1.16–1.68 fold higher odds of obesity, central obesity, and high body fat. Conclusions High MVPA is more important than high birth weight as a correlate of obesity in children. PMID:28544795

  15. Magnetic properties of doped Mn-Ga alloys made by mechanical milling and heat treatment

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

    Brown, Daniel R.; National High Magnetic Field Laboratory, Tallahassee, FL 32310; Han, Ke

    2016-05-15

    Mn-Ga alloys have shown hard magnetic properties, even though these alloys contain no rare-earth metals. However, much work is needed before rare-earth magnets can be replaced. We have examined the magnetic properties of bulk alloys made with partial replacement of both the Mn and Ga elements in the Mn{sub 0.8}Ga{sub 0.2} system. Bulk samples of Mn-Ga-Bi, Mn-Ga-Al, Mn-Fe-Ga and Mn-(FeB)-Ga alloys were fabricated and studied using mechanically milling and heat treatments while altering the atomic percentage of the third element between 2.5 and 20 at%. The ternary alloy exhibits all hard magnetic properties at room temperature with large coercivity. Annealedmore » Mn-Ga-X bulk composites exhibit high coercivities up to 16.6 kOe and remanence up to 9.8 emu/g, that is increased by 115% over the binary system.« less

  16. Ultrafast carrier dynamics in GaN/InGaN multiple quantum wells nanorods

    NASA Astrophysics Data System (ADS)

    Chen, Weijian; Wen, Xiaoming; Latzel, Michael; Yang, Jianfeng; Huang, Shujuan; Shrestha, Santosh; Patterson, Robert; Christiansen, Silke; Conibeer, Gavin

    2018-01-01

    GaN/InGaN multiple quantum wells (MQW) is a promising material for high-efficiency solid-state lighting. Ultrafast optical pump-probe spectroscopy is an important characterization technique for examining fundamental phenomena in semiconductor nanostructure with sub-picosecond resolution. In this study, ultrafast exciton and charge carrier dynamics in GaN/InGaN MQW planar layer and nanorod are investigated using femtosecond transient absorption (TA) techniques at room temperature. Here nanorods are fabricated by etching the GaN/InGaN MQW planar layers using nanosphere lithography and reactive ion etching. Photoluminescence efficiency of the nanorods have been proved to be much higher than that of the planar layers, but the mechanism of the nanorod structure improvement of PL efficiency is not adequately studied. By comparing the TA profile of the GaN/InGaN MQW planar layers and nanorods, the impact of surface states and nanorods lateral confinement in the ultrafast carrier dynamics of GaN/InGaN MQW is revealed. The nanorod sidewall surface states have a strong influence on the InGaN quantum well carrier dynamics. The ultrafast relaxation processes studied in this GaN/InGaN MQW nanostructure is essential for further optimization of device application.

  17. Pyramidal dislocation induced strain relaxation in hexagonal structured InGaN/AlGaN/GaN multilayer

    NASA Astrophysics Data System (ADS)

    Yan, P. F.; Du, K.; Sui, M. L.

    2012-10-01

    Due to the special dislocation slip systems in hexagonal lattice, dislocation dominated deformations in hexagonal structured multilayers are significantly different from that in cubic structured systems. In this work, we have studied the strain relaxation mechanism in hexagonal structured InGaN/AlGaN/GaN multilayers with transmission electron microscopy. Due to lattice mismatch, the strain relaxation was found initiated with the formation of pyramidal dislocations. Such dislocations locally lie at only one preferential slip direction in the hexagonal lattice. This preferential slip causes a shear stress along the basal planes and consequently leads to dissociation of pyramidal dislocations and operation of the basal plane slip system. The compressive InGaN layers and "weak" AlGaN/InGaN interfaces stimulate the dissociation of pyramidal dislocations at the interfaces. These results enhance the understanding of interactions between dislocations and layer interfaces and shed new lights on deformation mechanism in hexagonal-lattice multilayers.

  18. Ga metal nanoparticle-GaAs quantum molecule complexes for Terahertz generation.

    PubMed

    Bietti, Sergio; Basso Basset, Francesco; Scarpellini, David; Fedorov, Alexey; Ballabio, Andrea; Esposito, Luca; Elborg, Martin; Kuroda, Takashi; Nemcsics, Akos; Toth, Lajos; Manzoni, Cristian; Vozzi, Caterina; Sanguinetti, Stefano

    2018-06-18

    A hybrid metal-semiconductor nanosystem for the generation of THz radiation, based on the fabrication of GaAs quantum molecules-Ga metal nanoparticles complexes through a self assembly approach, is proposed. The role of the growth parameters, the substrate temperature, the Ga and As flux during the quantum dot molecule fabrication and the metal nanoparticle alignment is discussed. The tuning of the relative positioning of quantum dot molecules and metal nanoparticles is obtained through the careful control of Ga droplet nucleation sites via Ga surface diffusion. The electronic structure of a typical quantum dot molecule was evaluated on the base of the morphological characterizations performed by Atomic Force Microscopy and cross sectional Scanning Electron Microscopy, and the predicted results confirmed by micro-photoluminescence experiments, showing that the Ga metal nanoparticle-GaAs quantum molecule complexes are suitable for terahertz generation from intraband transition. . © 2018 IOP Publishing Ltd.

  19. Enhanced thermoelectric transport in modulation-doped GaN/AlGaN core/shell nanowires

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

    Song, Erdong; Li, Qiming; Swartzentruber, Brian

    2015-11-25

    The thermoelectric properties of unintentionally n-doped core GaN/AlGaN core/shell N-face nanowires are reported. We found that the temperature dependence of the electrical conductivity is consistent with thermally activated carriers with two distinctive donor energies. The Seebeck coefficient of GaN/AlGaN nanowires is more than twice as large as that for the GaN nanowires alone. However, an outer layer of GaN deposited onto the GaN/AlGaN core/shell nanowires decreases the Seebeck coefficient at room temperature, while the temperature dependence of the electrical conductivity remains the same. We attribute these observations to the formation of an electron gas channel within the heavily-doped GaN coremore » of the GaN/AlGaN nanowires. The room-temperature thermoelectric power factor for the GaN/AlGaN nanowires can be four times higher than the GaN nanowires. As a result, selective doping in bandgap engineered core/shell nanowires is proposed for enhancing the thermoelectric power.« less

  20. Simulation and optimization performance of GaAs/GaAs0.5Sb0.5/GaSb mechanically stacked tandem solar cells

    NASA Astrophysics Data System (ADS)

    Tayubi, Y. R.; Suhandi, A.; Samsudin, A.; Arifin, P.; Supriyatman

    2018-05-01

    Different approaches have been made in order to reach higher solar cells efficiencies. Concepts for multilayer solar cells have been developed. This can be realised if multiple individual single junction solar cells with different suitably chosen band gaps are connected in series in multi-junction solar cells. In our work, we have simulated and optimized solar cells based on the system mechanically stacked using computer simulation and predict their maximum performance. The structures of solar cells are based on the single junction GaAs, GaAs0.5Sb0.5 and GaSb cells. We have simulated each cell individually and extracted their optimal parameters (layer thickness, carrier concentration, the recombination velocity, etc), also, we calculated the efficiency of each cells optimized by separation of the solar spectrum in bands where the cell is sensible for the absorption. The optimal values of conversion efficiency have obtained for the three individual solar cells and the GaAs/GaAs0.5Sb0.5/GaSb tandem solar cells, that are: η = 19,76% for GaAs solar cell, η = 8,42% for GaAs0,5Sb0,5 solar cell, η = 4, 84% for GaSb solar cell and η = 33,02% for GaAs/GaAs0.5Sb0.5/GaSb tandem solar cell.

  1. An examination of the disparity between self-identified versus legally identified rape victimization: A pilot study.

    PubMed

    Marsil, Dorothy F; McNamara, Corinne

    2016-07-01

    Researchers compared rape victimization based on self-identification to the current federal legal definition in a pilot study of college students. The sample was comprised of 1,648 (69.8% female; 30.2% male) college students who completed the Sexual Experiences Survey-Short Form Victimization (SES-SFV) online. Based on the current legal definition of rape, 9.4% (11.1% female; 5.2% male) of students had been raped since being enrolled, but only 2.9% of students self-identified as being raped. Moreover, 15.1% of students reported ever being raped, with females acknowledging higher rates (19.7%) than males (4.3%). Rape continues to be a major issue for colleges and universities. A serious concern is the disparity between the number of those who met the behavioral criteria for rape victimization based on the current legal definition, but who did not self-identify as a victim. Universities must address this disparity by using multiple measures to assess the prevalence of sexual violence on campus.

  2. Fabrication and improved photoelectrochemical properties of a transferred GaN-based thin film with InGaN/GaN layers.

    PubMed

    Cao, Dezhong; Xiao, Hongdi; Gao, Qingxue; Yang, Xiaokun; Luan, Caina; Mao, Hongzhi; Liu, Jianqiang; Liu, Xiangdong

    2017-08-17

    Herein, a lift-off mesoporous GaN-based thin film, which consisted of a strong phase-separated InGaN/GaN layer and an n-GaN layer, was fabricated via an electrochemical etching method in a hydrofluoric acid (HF) solution for the first time and then transferred onto quartz or n-Si substrates, acting as photoanodes during photoelectrochemical (PEC) water splitting in a 1 M NaCl aqueous solution. Compared to the as-grown GaN-based film, the transferred GaN-based thin films possess higher and blue-shifted light emission, presumably resulting from an increase in the surface area and stress relaxation in the InGaN/GaN layer embedded on the mesoporous n-GaN. The properties such as (i) high photoconversion efficiency, (ii) low turn-on voltage (-0.79 V versus Ag/AgCl), and (iii) outstanding stability enable the transferred films to have excellent PEC water splitting ability. Furthermore, as compared to the film transferred onto the quartz substrate, the film transferred onto the n-Si substrate exhibits higher photoconversion efficiency (2.99% at -0.10 V) due to holes (h + ) in the mesoporous n-GaN layer that originate from the n-Si substrate.

  3. Peculiar hydrogenation process of Ce2Ni2Ga

    NASA Astrophysics Data System (ADS)

    Iwasieczko, Wacław; Kaczorowski, Dariusz

    2017-02-01

    Hydrogenation studies were carried out on the compound Ce2Ni2Ga that was described in the literature as an intermediate valence system. The alloy was found to absorb hydrogen very easily already at room temperature under pressure less than 0.1 MPa forming hydrides Ce2Ni2GaHx with x up 5.9, which are however multiphase and contain CeH2+δ and some other undisclosed phases. Analyses of the X-ray diffraction and magnetic data revealed that decomposition of the parent compound occurs immediately after its exposure to hydrogen. Synthesis under hydrogen pressure of 3 MPa at 470 K resulted in amorphous material with x=7.3. The Ce2Ni2GaHx system was found to exhibit a HDDR (hydrogenation, disproportionation, desorption, recombination) process.

  4. Weight maintenance and additional weight loss with liraglutide after low-calorie-diet-induced weight loss: the SCALE Maintenance randomized study.

    PubMed

    Wadden, T A; Hollander, P; Klein, S; Niswender, K; Woo, V; Hale, P M; Aronne, L

    2013-11-01

    Liraglutide, a once-daily human glucagon-like peptide-1 analog, induced clinically meaningful weight loss in a phase 2 study in obese individuals without diabetes. The present randomized phase 3 trial assessed the efficacy of liraglutide in maintaining weight loss achieved with a low-calorie diet (LCD). Obese/overweight participants (≥18 years, body mass index ≥30 kg m(-2) or ≥27 kg m(-2) with comorbidities) who lost ≥5% of initial weight during a LCD run-in were randomly assigned to liraglutide 3.0 mg per day or placebo (subcutaneous administration) for 56 weeks. Diet and exercise counseling were provided throughout the trial. Co-primary end points were percentage weight change from randomization, the proportion of participants that maintained the initial ≥5% weight loss, and the proportion that lost ≥5% of randomization weight (intention-to-treat analysis). ClinicalTrials.gov identifier: NCT00781937. Participants (n=422) lost a mean 6.0% (s.d. 0.9) of screening weight during run-in. From randomization to week 56, weight decreased an additional mean 6.2% (s.d. 7.3) with liraglutide and 0.2% (s.d. 7.0) with placebo (estimated difference -6.1% (95% class intervals -7.5 to -4.6), P<0.0001). More participants receiving liraglutide (81.4%) maintained the ≥5% run-in weight loss, compared with those receiving placebo (48.9%) (estimated odds ratio 4.8 (3.0; 7.7), P<0.0001), and 50.5% versus 21.8% of participants lost ≥5% of randomization weight (estimated odds ratio 3.9 (2.4; 6.1), P<0.0001). Liraglutide produced small but statistically significant improvements in several cardiometabolic risk factors compared with placebo. Gastrointestinal (GI) disorders were reported more frequently with liraglutide than placebo, but most events were transient, and mild or moderate in severity. Liraglutide, with diet and exercise, maintained weight loss achieved by caloric restriction and induced further weight loss over 56 weeks. Improvements in some

  5. Investigation of gate-diode degradation in normally-off p-GaN/AlGaN/GaN high-electron-mobility transistors

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

    Ťapajna, M., E-mail: milan.tapajna@savba.sk; Kuzmík, J.; Hilt, O.

    2015-11-09

    Gate diode conduction mechanisms were analyzed in normally-off p-GaN/AlGaN/GaN high-electron mobility transistors grown on Si wafers before and after forward bias stresses. Electrical characterization of the gate diodes indicates forward current to be limited by channel electrons injected through the AlGaN/p-GaN triangular barrier promoted by traps. On the other hand, reverse current was found to be consistent with carrier generation-recombination processes in the AlGaN layer. Soft breakdown observed after ∼10{sup 5 }s during forward bias stress at gate voltage of 7 V was attributed to formation of conductive channel in p-GaN/AlGaN gate stack via trap generation and percolation mechanism, likely due tomore » coexistence of high electric field and high forward current density. Possible enhancement of localized conductive channels originating from spatial inhomogeneities is proposed to be responsible for the degradation.« less

  6. A Comparative Study of AlGaN and InGaN Back-Barriers in Ultrathin-Barrier AlN/GaN Heterostructures

    NASA Astrophysics Data System (ADS)

    All Abbas, J. M.; Atmaca, G.; Narin, P.; Kutlu, E.; Sarikavak-Lisesivdin, B.; Lisesivdin, S. B.

    2017-08-01

    Investigations of the effects of back-barrier introduction on the two-dimensional electron gas (2DEG) of ultrathin-barrier AlN/GaN heterostructures with AlGaN and InGaN back-barriers are carried out using self-consistent solutions of 1-dimensional Schrödinger-Poisson equations. Inserted AlGaN and InGaN back-barriers are used to provide a good 2DEG confinement thanks to raising the conduction band edge of GaN buffer with respect to GaN channel layer. Therefore, in this paper the influence of these back-barrier layers on sheet carrier density, 2DEG confinement, and mobility are systematically and comparatively investigated. As a result of calculations, although sheet carrier density is found to decrease with InGaN back-barrier layer, it is not changed with AlGaN back-barrier layer for suggested optimise heterostructures. Obtained results can give some insights for further experimental studies.

  7. Whole-Body 68Ga-DOTANOC PET/MRI Versus 68Ga-DOTANOC PET/CT in Patients With Neuroendocrine Tumors

    PubMed Central

    Berzaczy, Dominik; Giraudo, Chiara; Haug, Alexander R.; Raderer, Markus; Senn, Daniela; Karanikas, Georgios; Weber, Michael; Mayerhoefer, Marius E.

    2017-01-01

    Purpose The aim of this study was to assess the diagnostic performance of simultaneous whole-body 68Ga-DOTANOC PET/MRI compared with 68Ga-DOTANOC PET/CT for detection of distant metastatic disease in patients with well-differentiated neuroendocrine tumors (NETs). Methods Patients with histologically proven, well-differentiated NET (G1 or G2) were included in this prospective, institutional review board–approved study. Patients underwent 68Ga-DOTANOC PET/CT and subsequent 68Ga-DOTANOC PET/MRI after a single tracer injection on the same day for staging or restaging purposes. Images were evaluated for the presence of NET lesions by 2 rater teams, each consisting of a nuclear medicine physician and a radiologist, in an observer-blinded fashion. Overall agreement, accuracy, sensitivity, and specificity, relative to a composite reference standard (consensus review including follow-up data), were calculated. Results Between July 2014 and June 2016, 28 patients were enrolled. Overall agreement and accuracy between the 2 rater teams were 91.7% (95% confidence interval [CI], 87.5%–95.9%) and 97% (95% CI, 94.4%–99.6%) for PET/MRI and 92.3% (95% CI, 88.3%–96.3%) and 94.6% (95% CI, 91.2%–98.1%) for PET/CT, respectively (P = 1.00). Overall, PET/MRI reached 89.8% sensitivity (95% CI, 77.8%–96.6%) and 100% specificity (95% CI, 97%–100%); PET/CT showed 81.6% sensitivity (95% CI, 68%–91.2%) and 100% specificity (95% CI, 97%–100%) for the detection of metastatic disease in NETs. Conclusions Whole-body 68Ga-DOTANOC PET/MRI appears to be comparable to 68Ga-DOTANOC PET/CT for lesion detection in patients with well-differentiated NETs. PMID:28682844

  8. Impact of Plasma Electron Flux on Plasma Damage‐Free Sputtering of Ultrathin Tin‐Doped Indium Oxide Contact Layer on p‐GaN for InGaN/GaN Light‐Emitting Diodes

    PubMed Central

    Son, Kwang Jeong; Kim, Tae Kyoung; Cha, Yu‐Jung; Oh, Seung Kyu; You, Shin‐Jae; Ryou, Jae‐Hyun

    2017-01-01

    Abstract The origin of plasma‐induced damage on a p‐type wide‐bandgap layer during the sputtering of tin‐doped indium oxide (ITO) contact layers by using radiofrequency‐superimposed direct current (DC) sputtering and its effects on the forward voltage and light output power (LOP) of light‐emitting diodes (LEDs) with sputtered ITO transparent conductive electrodes (TCE) is systematically studied. Changing the DC power voltage from negative to positive bias reduces the forward voltages and enhances the LOP of the LEDs. The positive DC power drastically decreases the electron flux in the plasma obtained by plasma diagnostics using a cutoff probe and a Langmuir probe, suggesting that the repulsion of plasma electrons from the p‐GaN surface can reduce plasma‐induced damage to the p‐GaN. Furthermore, electron‐beam irradiation on p‐GaN prior to ITO deposition significantly increases the forward voltages, showing that the plasma electrons play an important role in plasma‐induced damage to the p‐GaN. The plasma electrons can increase the effective barrier height at the ITO/deep‐level defect (DLD) band of p‐GaN by compensating DLDs, resulting in the deterioration of the forward voltage and LOP. Finally, the plasma damage‐free sputtered‐ITO TCE enhances the LOP of the LEDs by 20% with a low forward voltage of 2.9 V at 20 mA compared to LEDs with conventional e‐beam‐evaporated ITO TCE. PMID:29619312

  9. Impact of Plasma Electron Flux on Plasma Damage-Free Sputtering of Ultrathin Tin-Doped Indium Oxide Contact Layer on p-GaN for InGaN/GaN Light-Emitting Diodes.

    PubMed

    Son, Kwang Jeong; Kim, Tae Kyoung; Cha, Yu-Jung; Oh, Seung Kyu; You, Shin-Jae; Ryou, Jae-Hyun; Kwak, Joon Seop

    2018-02-01

    The origin of plasma-induced damage on a p -type wide-bandgap layer during the sputtering of tin-doped indium oxide (ITO) contact layers by using radiofrequency-superimposed direct current (DC) sputtering and its effects on the forward voltage and light output power (LOP) of light-emitting diodes (LEDs) with sputtered ITO transparent conductive electrodes (TCE) is systematically studied. Changing the DC power voltage from negative to positive bias reduces the forward voltages and enhances the LOP of the LEDs. The positive DC power drastically decreases the electron flux in the plasma obtained by plasma diagnostics using a cutoff probe and a Langmuir probe, suggesting that the repulsion of plasma electrons from the p -GaN surface can reduce plasma-induced damage to the p -GaN. Furthermore, electron-beam irradiation on p -GaN prior to ITO deposition significantly increases the forward voltages, showing that the plasma electrons play an important role in plasma-induced damage to the p -GaN. The plasma electrons can increase the effective barrier height at the ITO/deep-level defect (DLD) band of p -GaN by compensating DLDs, resulting in the deterioration of the forward voltage and LOP. Finally, the plasma damage-free sputtered-ITO TCE enhances the LOP of the LEDs by 20% with a low forward voltage of 2.9 V at 20 mA compared to LEDs with conventional e-beam-evaporated ITO TCE.

  10. Abortion legalized: challenges ahead.

    PubMed

    Singh, M; Jha, R

    2007-01-01

    To see whether advocacy for abortion law and comprehensive abortion care (CAC) sites after legalization of abortion in Nepal is adequate among educated people (above school leaving certificate). 150 participants were assigned randomly who agreed to be in the survey and were given structured questionnaires to find out their perception of abortion and CAC sites. Majority know abortion is legalized and majority have positive attitude about legalization of abortion, however majority are not aware of abortion service in CAC sites and none knew the cost of abortion service. Proper and adequate advocacy of the new abortion law and CAC service is essential.

  11. Laser induced OMCVD growth of AlGaAs on GaAs

    NASA Technical Reports Server (NTRS)

    Wilt, David M.; Warner, Joseph D.; Aron, Paul R.; Pouch, John J.; Hoffman, Richard W., Jr.

    1987-01-01

    A major factor limiting the efficiency of the GaAs-GaAlAs solar cell is the rate of recombination at the GaAs-AlGaAs interface. Evidence has been previously reported which indicates that recombination at this interface can be greatly reduced if the AlGaAs layer is grown at lower than normal temperatures. The authors examine the epitaxial growth of AlGaAs on GaAs using a horizontal OMCVD reactor and an excimer laser operating in the UV (lambda = 193 nm) region. The growth temperatures were 450 and 500 C. The laser beam was utilized in two orientations: 75 deg angle of incidence and parallel to the substrate. Film composition and structure were determined by Auger electron spectroscopy (AES) and transmission electron microscopy (TEM). Auger analysis of epilayers grown at 500 C with the laser impinging show no carbon or oxygen contamination of the epitaxial layers or interfaces. TEM diffraction patterns of these same epilayers exhibit single crystal (100) zone axis patterns.

  12. Umbilical choline and related methylamines betaine and dimethylglycine in relation to birth weight.

    PubMed

    Hogeveen, Marije; den Heijer, Martin; Semmekrot, Ben A; Sporken, Jan M; Ueland, Per M; Blom, Henk J

    2013-06-01

    Low birth weight (LBW) is associated with increased morbidity and mortality for the newborn and risk of chronic disease in adulthood. Choline plays an essential role in the integrity of cell membranes, methylation reactions, and memory development. We examined whether choline, betaine, and dimethylglycine (DMG) concentrations were associated with LBW in Dutch women. Blood was sampled from umbilical cords (UCs) at delivery in singleton pregnancies (n = 1,126). Maternal blood was sampled at 30-34 wk of gestational age (GA) (n = 366). We calculated birth weights standardized for GA and defined LBW as standardized birth weight ≤ 2,500 g. Maternal concentrations were lower as compared with UC concentrations and were not associated with birth weight. UC choline and betaine were inversely associated with birth weight (β = -60 (-89, -31) and β = -65 (-94, -36), respectively), whereas UC DMG was positively associated with birth weight (β = 35 (6.1, 63)). Odds ratios for LBW were 4.12 (1.15, 14.78), 5.68 (1.24, 25.91), and 0.48 (0.09, 2.65) for the highest UC choline, betaine, and DMG quartiles, respectively, as compared with the lowest quartiles. We observed an increased risk of LBW with increased umbilical choline and betaine in venous UC blood. These results might reflect a change in choline consumption or metabolism or a disturbed placental function.

  13. Making It Safe, Making It Legal, and Creating Peace of Mind

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

    Strom, Daniel J.

    2001-11-01

    The job of a medical or academic radiation safety officer has three parts: keeping it safe, keeping it legal, and helping people feel that they are safe. Absence of peace-of-mind about radiation protection matters can create very real health effects, even when there is little or no radiation exposure involved. Frightened people may make decisions such as changing jobs (and losing health insurance), terminating a pregnancy, or moving, all of which impact health. Furthermore, frightened people who choose to stick with it may suffer from anxiety, stress, insomnia, and weight loss or even weight gain. Genuinely listening to the concernsmore » of those who benefit from radiation safety services can help to provide peace-of-mind and minimize decisions that are risky to health.« less

  14. Electrical parameters of Au/n-GaN and Pt/n-GaN Schottky diodes

    NASA Astrophysics Data System (ADS)

    Kadaoui, Mustapha Amine; Bouiadjra, Wadi Bachir; Saidane, Abdelkader; Belahsene, Sofiane; Ramdane, Abderrahim

    2015-06-01

    Electrical properties of Si-doped GaN epitaxial layers, grown on a c-plane sapphire substrate by MOCVD to form Schottky diodes with Gold (Au) and platinum (Pt) and using Ti/Al/Au as Ohmic contact, are investigated. Characterization was performed through I-V and C-V-f measurements at room temperature. Schottky barrier height (Φb), ideality factor (n), and series resistance (Rs) were extracted from forward I-V characteriztics using Cheung and Lien methods. Φb, doping concentration (Nd) and Rs frequency dependence were extracted from C-V-f characteriztics. Pt/n-GaN shows a non-linear behavior with a barrier height of 0.63 eV, an ideality factor of 2.3, and series resistance of 63 Ω. Au/n-GaN behaves like two diodes in parallel with two barrier heights of (0.83 and 0.9 eV), two ideality factors of (5.8 and 3.18) and two series resistance of (10.6 and 68 Ω). Interface state properties in both samples have been investigated taking into account the bias dependence of the effective barrier height. The amount of stimulated traps along the energy-gap at the interface increases with voltage bias, which increases NSS exponentially from 4.24 ṡ 1013 to 3.67 ṡ 1014 eV-1 cm-2 in the range (Ec - 0.17) to (Ec - 0.61) eV for Pt/n-GaN, and from 2.3 ṡ 1013 to 1.14 ṡ 1014 eV-1 cm-2, in the range (Ec - 0.31) to (Ec - 0.82) eV for Au/n-GaN. The values of interface states density and series resistance for both samples are found to decrease with increasing frequency. Peak intensity was a measure of active interface states. C-V-f results confirm the model of the Schottky diode with a native interfacial insulator layer along the space charge region.

  15. Prospective comparison of 68Ga-PSMA PET/CT, 18F-sodium fluoride PET/CT and diffusion weighted-MRI at for the detection of bone metastases in biochemically recurrent prostate cancer.

    PubMed

    Zacho, Helle D; Nielsen, Julie B; Afshar-Oromieh, Ali; Haberkorn, Uwe; deSouza, Nandita; De Paepe, Katja; Dettmann, Katja; Langkilde, Niels C; Haarmark, Christian; Fisker, Rune V; Arp, Dennis T; Carl, Jesper; Jensen, Jørgen B; Petersen, Lars J

    2018-06-06

    To prospectively compare diagnostic accuracies for detection of bone metastases by 68 Ga-PSMA PET/CT, 18 F-NaF PET/CT and diffusion-weighted MRI (DW 600 -MRI) in prostate cancer (PCa) patients with biochemical recurrence (BCR). Sixty-eight PCa patients with BCR participated in this prospective study. The patients underwent 68 Ga-PSMA PET/CT, a 18 F-NaF PET/CT and a DW 600 -MRI (performed in accordance with European Society of Urogenital Radiology guidelines, with b values of 0 and 600 s/mm 2 ). Bone lesions were categorized using a three-point scale (benign, malignant or equivocal for metastases) and a dichotomous scale (benign or metastatic) for each imaging modality by at least two experienced observers. A best valuable comparator was defined for each patient based on study-specific imaging, at least 12 months of clinical follow-up and any imaging prior to the study and during follow-up. Diagnostic performance was assessed using a sensitivity analysis where equivocal lesions were handled as non-metastatic and then as metastatic. Ten of the 68 patients were diagnosed with bone metastases. On a patient level, sensitivity, specificity and the area under the curve (AUC) by receiver operating characteristic analysis were, respectively, 0.80, 0.98-1.00 and 0.89-0.90 for 68 Ga-PSMA PET/CT (n = 68 patients); 0.90, 0.90-0.98 and 0.90-0.94 for 18 NaF PET/CT (n = 67 patients); and 0.25-0.38, 0.87-0.92 and 0.59-0.62 for DW 600 -MRI (n = 60 patients). The diagnostic performance of DW 600 -MRI was significantly lower than that of 68 Ga-PSMA PET/CT and 18 NaF PET/CT for diagnosing bone metastases (p < 0.01), and no significant difference in the AUC was seen between 68 Ga-PSMA PET/CT and 18 NaF PET/CT (p = 0.65). 68 Ga-PSMA PET/CT and 18 F-NaF PET/CT showed comparable and high diagnostic accuracies for detecting bone metastases in PCa patients with BCR. Both methods performed significantly better than DW 600 -MRI, which was inadequate for diagnosing bone

  16. 17 CFR 39.27 - Legal risk considerations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Legal risk considerations. 39... CLEARING ORGANIZATIONS Compliance with Core Principles § 39.27 Legal risk considerations. (a) Legal... by the appropriate foreign licensing authority. (b) Legal framework. A derivatives clearing...

  17. On the dissolution properties of GaAs in Ga

    NASA Technical Reports Server (NTRS)

    Davidson, M. C.; Moynahan, A. H.

    1977-01-01

    The dissolution of GaAs in Ga was studied to determine the nature and cause of faceting effects. Ga was allowed to dissolve single crystalline faces under isothermal conditions. Of the crystalline planes with low number indices, only the (100) surface showed a direct correlation of dissolution sites to dislocations. The type of dissolution experienced depended on temperature, and there were three distinct types of behavior.

  18. Ultra-low specific contact resistivity (1.4 × 10-9 Ω.cm2) for metal contacts on in-situ Ga-doped Ge0.95Sn0.05 film

    NASA Astrophysics Data System (ADS)

    Wu, Ying; Luo, Sheng; Wang, Wei; Masudy-Panah, Saeid; Lei, Dian; Liang, Gengchiau; Gong, Xiao; Yeo, Yee-Chia

    2017-12-01

    A heavily Ga-doped Ge0.95Sn0.05 layer was grown on the Ge (100) substrate by molecular beam epitaxy (MBE), achieving an active doping concentration of 1.6 × 1020 cm-3 without the use of ion implantation and high temperature annealing that could cause Sn precipitation or surface segregation. An advanced nano-scale transfer length method was used to extract the specific contact resistivity ρc between the metal and the heavily doped p-Ge0.95Sn0.05 layer. By incorporating Sn into Ge and in-situ Ga doping during the MBE growth, an ultra-low ρc of 1.4 × 10-9 Ω.cm2 was achieved, which is 50% lower than the ρc of p+-Ge control and is also the lowest value obtained for metal/p-type semiconductor contacts.

  19. Near ultraviolet InGaN/AlGaN-based light-emitting diodes with highly reflective tin-doped indium oxide/Al-based reflectors.

    PubMed

    Choi, Chang-Hoon; Han, Jaecheon; Park, Jae-Seong; Seong, Tae-Yeon

    2013-11-04

    The enhanced light output power of a InGaN/AlGaN-based light-emitting diodes (LEDs) using three different types of highly reflective Sn-doped indium oxide (ITO)/Al-based p-type reflectors, namely, ITO/Al, Cu-doped indium oxide (CIO)/s-ITO(sputtered)/Al, and Ag nano-dots(n-Ag)/CIO/s-ITO/Al, is presented. The ITO/Al-based reflectors exhibit lower reflectance (76 - 84% at 365 nm) than Al only reflector (91.1%). However, unlike Al only n-type contact, the ITO/Al-based contacts to p-GaN show good ohmic characteristics. Near-UV (365 nm) InGaN/AlGaN-based LEDs with ITO/Al, CIO/s-ITO/Al, and n-Ag/CIO/s-ITO/Al reflectors exhibit forward-bias voltages of 3.55, 3.48, and 3.34 V at 20 mA, respectively. The LEDs with the ITO/Al and CIO/s-ITO/Al reflectors exhibit 9.5% and 13.5% higher light output power (at 20 mA), respectively, than the LEDs with the n-Ag/CIO/s-ITO/Al reflector. The improved performance of near UV LEDs is attributed to the high reflectance and low contact resistivity of the ITO/Al-based reflectors, which are better than those of conventional Al-based reflectors.

  20. 45 CFR 1626.9 - Change in circumstances.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ON LEGAL ASSISTANCE TO ALIENS § 1626.9 Change in circumstances. If, to the knowledge of the recipient... representation is prohibited by this part and a recipient must discontinue representation consistent with...