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Sample records for acid tetrahydrate sat

  1. Dissolution of sulfuric acid tetrahydrate at low temperatures and subsequent growth of nitric acid trihydrate

    NASA Astrophysics Data System (ADS)

    Iraci, Laura T.; Fortin, Tara J.; Tolbert, Margaret A.

    1998-04-01

    Crystalline sulfuric acid tetrahydrate (SAT) has been observed to change phase at temperatures below its melting point, in agreement with recent theoretical predictions of deliquescence. Dissolution of SAT was observed in 63% of experiments expected to show a phase change, leading to formation of a ternary HNO3/H2SO4/H2O solution. This solution, which still contained a portion of the original solid SAT, crystallized to form nitric acid trihydrate (NAT). NAT then continued to grow by condensation of additional nitric acid and water at temperatures several degrees above the ice frost point. This process of SAT dissolution followed by NAT crystallization and growth may offer a mechanism for the formation of type Ia polar stratospheric clouds on frozen sulfate aerosols when SNAT>15.

  2. Radiolysis of Sulfuric Acid, Sulfuric Acid Monohydrate, and Sulfuric Acid Tetrahydrate and Its Relevance to Europa

    NASA Technical Reports Server (NTRS)

    Loeffler, M. J.; Hudson, R. L.; Moore, M. H.; Carlson, R. W.

    2011-01-01

    We report laboratory studies on the 0.8 MeV proton irradiation of ices composed of sulfuric acid (H2SO4), sulfuric acid monohydrate (H2SO4 H2O), and sulfuric acid tetrahydrate (H2SO4 4H2O) between 10 and 180 K. Using infrared spectroscopy, we identify the main radiation products as H2O, SO2, (S2O3)x, H3O+, HSO4(exp -), and SO4(exp 2-). At high radiation doses, we find that H2SO4 molecules are destroyed completely and that H2SO4 H2O is formed on subsequent warming. This hydrate is significantly more stable to radiolytic destruction than pure H2SO4, falling to an equilibrium relative abundance of 50% of its original value on prolonged irradiation. Unlike either pure H2SO4 or H2SO4 H2O, the loss of H2SO4 4H2O exhibits a strong temperature dependence, as the tetrahydrate is essentially unchanged at the highest irradiation temperatures and completely destroyed at the lowest ones, which we speculate is due to a combination of radiolytic destruction and amorphization. Furthermore, at the lower temperatures it is clear that irradiation causes the tetrahydrate spectrum to transition to one that closely resembles the monohydrate spectrum. Extrapolating our results to Europa s surface, we speculate that the variations in SO2 concentrations observed in the chaotic terrains are a result of radiation processing of lower hydration states of sulfuric acid and that the monohydrate will remain stable on the surface over geological times, while the tetrahydrate will remain stable in the warmer regions but be destroyed in the colder regions, unless it can be reformed by other processes, such as thermal reactions induced by diurnal cycling.

  3. Heterogeneous Interactions of ClONO2 and HCl with Sulfuric Acid Tetrahydrate: Implications for the Stratosphere

    NASA Technical Reports Server (NTRS)

    Zhang, Renyi; Jayne, John T.; Molina, Mario J.

    1994-01-01

    The reaction probabilities for ClONO2+H2O- HOCl + HNO3 and ClONO2+ HCl Cl2 +HNO3 have been investigated on sulfuric acid tetrahydrate (SAT, H2SO4-4H2O)surfaces at temperatures between 190 and 230 K and at reactant concentrations that are typical in the lower stratosphere, using a fast-flow reactor coupled to a quadrupole mass spectrometer. The results indicate that the reaction probabilities as well as HCl uptake depend strongly on the thermodynamic state of SAT surface: they decrease significantly with decreasing H2O partial pressure at a given temperature, and decrease with increasing temperature at a given H2O partial pressure, as the SAT changes from the H2O-rich form to the H2SO4-rich form. For H2O-rich SAT at 195 K gamma(sub 1) approx. = -0.01 and gamma(sub 2) greater or equal to 0.1, whereas the values for H2SO4-rich SAT decrease by more than 2 orders of magnitude. At low concentrations of HCl, close to those found in the stratosphere, the amount of HCl taken up by H2O-rich SAT films corresponds to a coverage of the order of a tenth of a monolayer (approx. = 10(exp 14) molecules/sq cm); H2SO4-rich SAT films take up 2 orders of magnitude less HCl (les than 10(exp 12) molecules/sq cm). Substantial HCl uptake at high HCl concentrations is also observed, as a result of surface melting. The data reveal that frozen stratospheric sulfate aerosols may play an important role in chlorine activation in the winter polar stratosphere via processes similar to those occurring on the surfaces of polar stratospheric cloud particles.

  4. Actinide sulfite tetrahydrate and actinide oxysulfite tetrahydrate

    SciTech Connect

    Baugh, D.; Watt, G.

    1980-07-08

    A compound is prepared that comprises an actinide sulfite tetrahydrate selected from the group consisting of uranium (IV) sulfite tetrahydrate and plutonium (IV) sulfite tetrahydrate. A compound is also prepared that comprises an actinide oxysulfite tetrahydrate selected from the group consisting of uranium (IV) oxysulfite tetrahydrate and plutonium (IV) oxysulfite tetrahydrate

  5. Synthesis, structure refinement and characterization of tetrahydrated acid gadolinium diphosphate HGdP{sub 2}O{sub 7}.4H{sub 2}O

    SciTech Connect

    Hraiech, Sana; Chehimi-Moumen, Fathia . E-mail: fathia.chehimi@fsb.rnu.tn; Ferid, Mokhtar; Hassen-Chehimi, D. Ben; Trabelsi-Ayadi, Malika

    2005-12-08

    Synthesis and single crystal structure are reported for a new gadolinium acid diphosphate tetrahydrate HGdP{sub 2}O{sub 7}.4H{sub 2}O. This salt crystallizes in the monoclinic system, space group P2{sub 1}/n, with the following unit-cell parameters: a=6.6137(2)A, b=11.4954(4)A, c=11.377(4)A, {beta}=87.53(2){sup o} and Z=4. Its crystal structure was refined to R=0.0333 using 1783 reflections. The corresponding atomic arrangement can be described as an alternation of corrugated layers of monohydrogendiphosphate groups and GdO{sub 8} polyhedra parallel to the (1-bar 01) plane. The cohesion between the different diphosphoric groups is provided by strong hydrogen bonding involving the W4 water molecule. IR and Raman spectra of HGdP{sub 2}O{sub 7}.4H{sub 2}O confirm the existence of the characteristic bands of diphosphate group in 980-700cm{sup -1} area. The IR spectrum reveals also the characteristic bands of water molecules vibration (3600-3230cm{sup -1}) and acidic hydrogen ones (2340cm{sup -1}). TG and DTA investigations show that the dehydration of this salt occurs between 79 and 900 deg. C. It decomposes after dehydration into an amorphous phase. Gadolinium diphosphate Gd{sub 4}(P{sub 2}O{sub 7}){sub 3} was obtained by heating HGdP{sub 2}O{sub 7}.4H{sub 2}O in a static air furnace at 850 deg. C for 48h.

  6. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Boric acid and its salts, borax... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1121 Boric acid and its... the requirement of a tolerance is established for residues of the pesticidal chemical boric acid...

  7. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Boric acid and its salts, borax... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1121 Boric acid and its... the requirement of a tolerance is established for residues of the pesticidal chemical boric acid...

  8. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Boric acid and its salts, borax... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1121 Boric acid and its... the requirement of a tolerance is established for residues of the pesticidal chemical boric acid...

  9. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Boric acid and its salts, borax... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1121 Boric acid and its... the requirement of a tolerance is established for residues of the pesticidal chemical boric acid...

  10. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Boric acid and its salts, borax... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1121 Boric acid and its... the requirement of a tolerance is established for residues of the pesticidal chemical boric acid...

  11. Characterization of the sat Operon in Streptococcus mutans: Evidence for a Role of Ffh in Acid Tolerance

    PubMed Central

    Kremer, Bas H. A.; van der Kraan, Marieke; Crowley, Paula J.; Hamilton, Ian R.; Brady, L. Jeannine; Bleiweis, Arnold S.

    2001-01-01

    An essential protein translocation pathway in Escherichia coli and Bacillus subtilis involves the signal recognition particle (SRP), of which the 54-kDa homolog (Ffh) is an essential component. In a previous study, we found that a transposon insertion in the ylxM-ffh intergenic region of the designated secretion and acid tolerance (sat) operon of Streptococcus mutans resulted in an acid-sensitive phenotype. In the present study, we further characterized this genomic region in S. mutans after construction of bonafide sat operon mutants and confirmed the role of the SRP pathway in acid resistance. Northern blot and primer extension analyses identified an acid-inducible promoter upstream of ylxM that was responsible for upregulating the coordinate expression of all five genes of the sat operon when cells were grown at acid pH. Two constitutive promoters, one immediately upstream of satD and one just 3′ to the acid-inducible promoter, were also identified. Except for Ffh, the functions of the sat operon gene products are unknown. SatC, SatD, and SatE have no homology to proteins with known functions, although YlxM may function as a transcriptional regulator linked to genes encoding SRP pathway proteins. Nonpolar mutations created in each of the five genes of the sat locus resulted in viable mutants. Most striking, however, was the finding that a mutation in ffh did not result in loss of cell viability, as is the case in all other microbial species in which this pathway has been described. This mutant also lacked immunologically detectable Ffh and was severely affected in resistance to acid. Complementation of the mutation resulted in restoration of acid tolerance and reappearance of cytoplasmic Ffh. These data provide evidence that the SRP pathway plays an important role in acid tolerance in S. mutans. PMID:11274114

  12. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-01-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  13. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Astrophysics Data System (ADS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-05-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1 - 3 × 10-4 Torr H2O and 1 - 2.5 × 10-6 Torr HNO3) and subjected to cooling and heating cycles. FTIR spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  14. Laboratory studies of the formation of polar stratospheric clouds: Nitric acid condensation on thin sulfuric acid films

    NASA Astrophysics Data System (ADS)

    Iraci, Laura T.; Middlebrook, Ann M.; Tolbert, Margaret A.

    1995-10-01

    Thin sulfuric acid films were exposed to 5 × 10-8 - 8 × 10-7 torr HNO3 and 2 - 3 × 10-4 torr H2O and cooled to temperatures near the ice frost point. Fourier transform infrared (FTIR) spectroscopy was used to probe the condensed-phase species during isothermal experiments, and gas pressures were monitored with mass spectrometry. Supercooled liquid sulfuric acid films exposed to HNO3 (6 ≤ SNAT ≤ 114) showed indications of HNO3 uptake to form ternary solutions of approximately 4 wt % HNO3, 38 wt % H2SO4, and 59 wt % H2O, followed by crystallization of nitric acid trihydrate (NAT). NAT crystallization did not initiate significant crystallization of the supercooled H2SO4, but the H2SO4 often crystallized to sulfuric acid tetrahydrate (SAT) upon warming. In contrast, when crystalline SAT films were exposed to HNO3 and water, NAT did not condense within several hours, even at HNO3 saturation ratios of 30 or higher. Calculations of the contact parameter from experimental data indicate that m <0.76 for NAT on SAT. Our film studies suggest that crystalline polar stratospheric cloud (PSC) growth is most easily accomplished when stratospheric sulfate aerosols (SSAs) remain liquid, absorb HNO3, and produce crystalline nitric acid trihydrate via heterogeneous nucleation. If SSAs crystallize to SAT at some point during the winter, nitric acid condensation is hindered, and PSC formation could become more difficult.

  15. Analysis of SAT Type Foot-And-Mouth Disease Virus Capsid Proteins and the Identification of Putative Amino Acid Residues Affecting Virus Stability

    PubMed Central

    Maree, Francois F.; Blignaut, Belinda; de Beer, Tjaart A. P.; Rieder, Elizabeth

    2013-01-01

    Foot-and-mouth disease virus (FMDV) initiates infection by adhering to integrin receptors on target cells, followed by cell entry and disassembly of the virion through acidification within endosomes. Mild heating of the virions also leads to irreversible dissociation into pentamers, a characteristic linked to reduced vaccine efficacy. In this study, the structural stability of intra- and inter-serotype chimeric SAT2 and SAT3 virus particles to various conditions including low pH, mild temperatures or high ionic strength, was compared. Our results demonstrated that while both the SAT2 and SAT3 infectious capsids displayed different sensitivities in a series of low pH buffers, their stability profiles were comparable at high temperatures or high ionic strength conditions. Recombinant vSAT2 and intra-serotype chimeric viruses were used to map the amino acid differences in the capsid proteins of viruses with disparate low pH stabilities. Four His residues at the inter-pentamer interface were identified that change protonation states at pH 6.0. Of these, the H145 of VP3 appears to be involved in interactions with A141 in VP3 and K63 in VP2, and may be involved in orientating H142 of VP3 for interaction at the inter-pentamer interfaces. PMID:23717387

  16. Mapping of amino acid residues responsible for adhesion of cell culture-adapted foot-and-mouth disease SAT type viruses.

    PubMed

    Maree, Francois F; Blignaut, Belinda; de Beer, Tjaart A P; Visser, Nico; Rieder, Elizabeth A

    2010-10-01

    Foot-and-mouth disease virus (FMDV) infects host cells by adhering to the alpha(V) subgroup of the integrin family of cellular receptors in a Arg-Gly-Asp (RGD) dependent manner. FMD viruses, propagated in non-host cell cultures are reported to acquire the ability to enter cells via alternative cell surface molecules. Sequencing analysis of SAT1 and SAT2 cell culture-adapted variants showed acquisition of positively charged amino acid residues within surface-exposed loops of the outer capsid structural proteins. The fixation of positively charged residues at position 110-112 in the beta F-beta G loop of VP1 of SAT1 isolates is thought to correlate with the acquisition of the ability to utilise alternative glycosaminoglycan (GAG) molecules for cell entry. Similarly, two SAT2 viruses that adapted readily to BHK-21 cells accumulated positively charged residues at positions 83 and 85 of the beta D-beta E loop of VP1. Both regions surround the fivefold axis of the virion. Recombinant viruses containing positively charged residues at position 110 and 112 of VP1 were able to infect CHO-K1 cells (that expresses GAG) and demonstrated increased infectivity in BHK-21 cells. Therefore, recombinant SAT viruses engineered to express substitutions that induce GAG-binding could be exploited in the rational design of vaccine seed stocks with improved growth properties in cell cultures. PMID:20637812

  17. Analysis of SAT type foot-and-mouth disease virus capsid proteins and the identification of putative amino acid residues affecting virus stability.

    PubMed

    Maree, Francois F; Blignaut, Belinda; de Beer, Tjaart A P; Rieder, Elizabeth

    2013-01-01

    Foot-and-mouth disease virus (FMDV) initiates infection by adhering to integrin receptors on target cells, followed by cell entry and disassembly of the virion through acidification within endosomes. Mild heating of the virions also leads to irreversible dissociation into pentamers, a characteristic linked to reduced vaccine efficacy. In this study, the structural stability of intra- and inter-serotype chimeric SAT2 and SAT3 virus particles to various conditions including low pH, mild temperatures or high ionic strength, was compared. Our results demonstrated that while both the SAT2 and SAT3 infectious capsids displayed different sensitivities in a series of low pH buffers, their stability profiles were comparable at high temperatures or high ionic strength conditions. Recombinant vSAT2 and intra-serotype chimeric viruses were used to map the amino acid differences in the capsid proteins of viruses with disparate low pH stabilities. Four His residues at the inter-pentamer interface were identified that change protonation states at pH 6.0. Of these, the H145 of VP3 appears to be involved in interactions with A141 in VP3 and K63 in VP2, and may be involved in orientating H142 of VP3 for interaction at the inter-pentamer interfaces. PMID:23717387

  18. Optical absorption spectrum of Cu 2+ in calcium tartrate tetrahydrate

    NASA Astrophysics Data System (ADS)

    Swamy, Y. K. R.; Reddy, P. P.; Reddy, Y. P.

    1980-02-01

    Copper doped single crystals of calcium tartrate tetrahydrate are grown from silica gel. The optical absorption spectrum is investigated with polarised and unpolarised beams of incident light. The spectrum is attributed to the Cu 2+ ion in C 4V symmetry associated with spin-orbit coupling. The following crystal field parameters are evaluated: Dq = 1000 cm -1; λ = -830 cm -1; Ds = 1540 cm -1; Dt = 470 cm -1.

  19. Freezing nucleation of levitated single sulfuric acid/H 2O micro-droplets. A combined Raman- and Mie spectroscopic study

    NASA Astrophysics Data System (ADS)

    Mund, C.; Zellner, R.

    2003-12-01

    The phase behaviour of single sulfuric acid/H 2O micro-droplets upon supercooling has been studied using optical levitation of such droplets in combination with Raman- and Mie spectroscopy for chemical and size analysis. It is found that the freezing nucleation behaviour depends on the sulfuric acid concentration of the droplets and hence the region of the phase diagram which is reached upon cooling. Whereas for diluted droplets (c H2SO4<30 wt%) instantaneous ice nucleation is observed, more concentrated droplets tend to supercool with no tendency to nucleate the thermodynamically stable hydrate phase sulfuric acid tetrahydrate (SAT) or sulfuric acid monohydrate (SAM). The upper limits of the nucleation rate in this regime were determined to be J≤5×10 5 cm -3 s -1.

  20. Effective preprocessing in #SAT

    NASA Astrophysics Data System (ADS)

    Guo, Qin; Sang, Juan; He, Yong-mei

    2011-12-01

    Preprocessing #SAT instances can reduce their size considerably and decrease the solving time. In this paper we investigate the use of the hyper-binary resolution and equality reduction to preprocess the #SAT instances. And a preprocessing algorithm Preprocess MC is presented, which combines the unit propagation, the hyper-binary resolution, and the equality reduction together. The experiment shows that these excellent technologies not only reduce the size of the #SAT formula, but also improve the ability of the model counters to solve #SAT problems.

  1. Surviving Without the SAT

    ERIC Educational Resources Information Center

    McDermott, Ann

    2008-01-01

    Scholastic Aptitude Test (SAT) scores still wield a mighty force in American culture and in the psyches of teenagers, even though 760 American colleges and universities have made standardized testing an optional part of the admissions process. Three years ago, after the new writing portion of the SAT was unveiled, the author's college, the College…

  2. Disabling the SAT.

    ERIC Educational Resources Information Center

    Freedman, Miriam Kurtzig

    2003-01-01

    Argues the College Boards' decision to stop flagging the SAT scores of students with disabilities given extended time to take the test will compromise the test's validity. A civil rights organization urged the College Board to stop flagging SAT scores because the practice violated the rights of students with disabilities. Proposes three…

  3. SmallSat Database

    NASA Technical Reports Server (NTRS)

    Petropulos, Dolores; Bittner, David; Murawski, Robert; Golden, Bert

    2015-01-01

    The SmallSat has an unrealized potential in both the private industry and in the federal government. Currently over 70 companies, 50 universities and 17 governmental agencies are involved in SmallSat research and development. In 1994, the U.S. Army Missile and Defense mapped the moon using smallSat imagery. Since then Smart Phones have introduced this imagery to the people of the world as diverse industries watched this trend. The deployment cost of smallSats is also greatly reduced compared to traditional satellites due to the fact that multiple units can be deployed in a single mission. Imaging payloads have become more sophisticated, smaller and lighter. In addition, the growth of small technology obtained from private industries has led to the more widespread use of smallSats. This includes greater revisit rates in imagery, significantly lower costs, the ability to update technology more frequently and the ability to decrease vulnerability of enemy attacks. The popularity of smallSats show a changing mentality in this fast paced world of tomorrow. What impact has this created on the NASA communication networks now and in future years? In this project, we are developing the SmallSat Relational Database which can support a simulation of smallSats within the NASA SCaN Compatability Environment for Networks and Integrated Communications (SCENIC) Modeling and Simulation Lab. The NASA Space Communications and Networks (SCaN) Program can use this modeling to project required network support needs in the next 10 to 15 years. The SmallSat Rational Database could model smallSats just as the other SCaN databases model the more traditional larger satellites, with a few exceptions. One being that the smallSat Database is designed to be built-to-order. The SmallSat database holds various hardware configurations that can be used to model a smallSat. It will require significant effort to develop as the research material can only be populated by hand to obtain the unique data

  4. Disodium octaborate tetrahydrate treatments to slash pine for protection against formosan subterranean termite and eastern subterranean termite (isoptera: rhinotermitidae)

    SciTech Connect

    Mauldin, J.K.; Kard, B.M.

    1996-06-01

    Minimum retentions of disodium octaborate tetrahydrate (DOT) needed in slash pine, Pinus elliottii Engelm. variety elliottii, wood to provide maximum protection against 2 species of subterranean termites were determined in choice and no-choice laboratory tests. Efficacy criteria for DOT were greater or equal to 90% termite mortality and equal to or less than 5% loss in weight of treated wooden blocks. For termites fed only DOT-treated wood, 0.10 and 0.30% boric acid equivalent (BAE, percentage of boric acid based on dry weight of wood, assuming all boron is present as boric acid) protected wood from the eastern subterranean termite, Reticulitermes flavipes (Kollar), and Formosan subterranean termite, Coptotermes formosanus Shiraki, respectively. When termites had a choice between treated or nontreated wooden blocks were not in contact with soil or exposed to rain, a BAE of 0.30% protected the wood from naturally occuring Reticulitermes sp. for 18 mo. In wooden structures under constant pressure from subterranean termites, concentrations greater than 0.54% BAE may be required to protect wood, especially against C. formosanus.

  5. Crystal structure and hydrogen bonding in the water-stabilized proton-transfer salt brucinium 4-amino-phenyl-arsonate tetra-hydrate.

    PubMed

    Smith, Graham; Wermuth, Urs D

    2016-05-01

    In the structure of the brucinium salt of 4-amino-phenyl-arsonic acid (p-arsanilic acid), systematically 2,3-dimeth-oxy-10-oxostrychnidinium 4-amino-phenyl-ar-son-ate tetra-hydrate, (C23H27N2O4)[As(C6H7N)O2(OH)]·4H2O, the brucinium cations form the characteristic undulating and overlapping head-to-tail layered brucine substructures packed along [010]. The arsanilate anions and the water mol-ecules of solvation are accommodated between the layers and are linked to them through a primary cation N-H⋯O(anion) hydrogen bond, as well as through water O-H⋯O hydrogen bonds to brucinium and arsanilate ions as well as bridging water O-atom acceptors, giving an overall three-dimensional network structure. PMID:27308034

  6. Human disodium octaborate tetrahydrate exposure following carpet flea treatment is not associated with significant dermal absorption.

    PubMed

    Krieger, R I; Dinoff, T M; Peterson, J

    1996-01-01

    Disodium octaborate tetrahydrate is used for indoor flea control on carpets and furniture. Disodium octaborate tetrahydrate was applied to a 100% nylon carpet as a solution using a powered rug brush at a rate of approximately 200 micrograms/cm2 carpet. Two randomly chosen groups of volunteers (18 females, 4 males) wore either bathing suits which provided 75% or more skin exposure or whole-body, cotton dosimeters consisting of socks, union suits, and gloves. The volunteers performed a 20-minute set of Jazzercise routines. The availability of boron was demonstrated by covering portions of the carpet with a cotton dosimeter and rolling it with a weighted roller. Additionally, disodium octaborate tetrahydrate was transferred to the whole-body dosimeter. Volunteers also collected 24-hour urine specimens prior to and following the exercise period. The specimens were analyzed for total boron by inductively coupled plasma emission spectroscopy. No evidence of contact transfer and dermal absorption was obtained. The mean daily boron levels (mg/g creatinine) were 1.17, 1.33, and 1.31 for the group with exposed skin and 1.26, 1.12, and 1.26 for those who wore dosimeters which prevented contact. Daily urine boron levels were not significantly different when compared using a two sample t-test assuming equal variances (P > 0.05). Direct dermal contact with disodium octaborate tetrahydrate-treated carpet at a nominal rate of 200 micrograms/cm2 did not produce any adverse effects or change urinary boron clearance. PMID:8889949

  7. Infrared studies of sulfuric acid and its impact on polar and global ozone

    NASA Astrophysics Data System (ADS)

    Iraci, Laura Tracy

    Sulfuric acid aerosols are present throughout the lower stratosphere and play an important role in both polar and global ozone depletion. In the polar regions, stratospheric sulfate aerosols (SSAs) act as nuclei for the growth of polar stratospheric clouds (PSCs). Heterogeneous reactions can occur on these PSCs, leading to chlorine activation and catalytic ozone destruction. This thesis addresses the issue of polar ozone depletion through laboratory studies which examine the nucleation of PSCs on sulfuric acid. In addition, chemistry which occurs directly on sulfate aerosols may impact ozone at midlatitudes, and studies describing one such reaction are presented as well. To study the growth of type I PSCs on sulfuric acid, thin H2SO4 films were exposed to water and nitric acid vapors at stratospheric temperatures. Fourier transform infrared spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films which condensed. Supercooled liquid sulfuric acid films showed uptake of HNO3 to form ternary solutions, followed by crystallization of nitric acid trihydrate (NAT). When crystalline sulfuric acid tetrahydrate (SAT) films were exposed to nitric acid and water, condensation of a supercooled HNO3/H2O layer was often observed. As predicted by theory, some of the SAT crystal then dissolved, creating a ternary H2SO4/HNO3/H2O solution. From this solution, NAT nearly always crystallized, halting the phase change of sulfuric acid. If a supercooled nitric acid layer did not condense on frozen sulfuric acid, crystalline NAT was not deposited from the gas phase when SNAT/leq41. At significantly higher supersaturations, NAT could be forced to condense on sulfuric acid, regardless of its phase. Calculations of the contact parameter from experimental data indicate that m<0.79 for NAT on SAT, predicting a significant barrier to nucleation of NAT from the gas phase. While PSCs can form only in the cold polar regions of the stratosphere, sulfuric

  8. Active CryoCubeSat

    NASA Technical Reports Server (NTRS)

    Swenson, Charles

    2016-01-01

    The Active CryoCubeSat project will demonstrate an advanced thermal control system for a 6-Unit (6U) CubeSat platform. A miniature, active thermal control system, in which a fluid is circulated in a closed loop from thermal loads to radiators, will be developed. A miniature cryogenic cooler will be integrated with this system to form a two-stage thermal control system. Key components will be miniaturized by using advanced additive manufacturing techniques resulting in a thermal testbed for proving out these technologies. Previous CubeSat missions have not tackled the problem of active thermal control systems nor have any past or current CubeSat missions included cryogenic instrumentation. This Active CryoCubeSat development effort will provide completely new capacities for CubeSats and constitutes a major advancement over the state-of-the-art in CubeSat thermal control.

  9. CarbonSat Constellation

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Tobehn, Carsten; Ernst, Robert; Bovensmann, Heinrich; Buchwitz, Michael; Burrows, John P.; Notholt, John

    1 Carbon dioxide (CO2) and methane (CH4) are the most important manmade greenhouse gases (GHGs) which are driving global climate change. Currently, the CO2 measurements from the ground observing network are still the main sources of information but due to the limited number of measurement stations the coverage is limited. In addition, CO2 monitoring and trading is often based mainly on bottom-up calculations and an independent top down verification is limited due to the lack of global measurement data with local resolution. The first CO2 and CH4 mapping from SCIAMACHY on ENVISAT shows that satellites add important missing global information. Current GHG measurement satellites (GOSAT)are limited either in spatial or temporal resolution and coverage. These systems have to collect data over a year or even longer to produce global regional fluxes products. Conse-quently global, timely, higher spatial resolution and high accuracy measurement are required for: 1. A good understanding of the CO2 and CH4 sources and sinks for reliable climate predic-tion; and 2. Independent and transparent verification of accountable sources and sinks in supporting Kyoto and upcoming protocols The CarbonSat constellation idea comes out the trade off of resolution and swath width during CarbonSat mission definition studies. In response to the urgent need to support the Kyoto and upcoming protocols, a feasibility study has been carried out. The proposed solution is a constellation of five CarbonSat satellites in 614km LTAN 13:00, which is able to provide global, daily CO2 and CH4 measurement everywhere on the Earth with high spatial resolution 2 × 2 km and low uncertainty lt;2ppm (CO2) and lt;8ppb (CH4). The unique global daily measurement capability significantly increases the number of cloud free measurements, which enables more reliable services associated with reduced uncertainty, e.g. to 0.15ppm (CO2) per month in 10km and even more timely products. The CarbonSat Constellation in

  10. CubeSat Launch Initiative

    NASA Technical Reports Server (NTRS)

    Higginbotham, Scott

    2016-01-01

    The National Aeronautics and Space Administration (NASA) recognizes the tremendous potential that CubeSats (very small satellites) have to inexpensively demonstrate advanced technologies, collect scientific data, and enhance student engagement in Science, Technology, Engineering, and Mathematics (STEM). The CubeSat Launch Initiative (CSLI) was created to provide launch opportunities for CubeSats developed by academic institutions, non-profit entities, and NASA centers. This presentation will provide an overview of the CSLI, its benefits, and its results.

  11. SDO FlatSat Facility

    NASA Technical Reports Server (NTRS)

    Amason, David L.

    2008-01-01

    The goal of the Solar Dynamics Observatory (SDO) is to understand and, ideally, predict the solar variations that influence life and society. It's instruments will measure the properties of the Sun and will take hifh definition images of the Sun every few seconds, all day every day. The FlatSat is a high fidelity electrical and functional representation of the SDO spacecraft bus. It is a high fidelity test bed for Integration & Test (I & T), flight software, and flight operations. For I & T purposes FlatSat will be a driver to development and dry run electrical integration procedures, STOL test procedures, page displays, and the command and telemetry database. FlatSat will also serve as a platform for flight software acceptance and systems testing for the flight software system component including the spacecraft main processors, power supply electronics, attitude control electronic, gimbal control electrons and the S-band communications card. FlatSat will also benefit the flight operations team through post-launch flight software code and table update development and verification and verification of new and updated flight operations products. This document highlights the benefits of FlatSat; describes the building of FlatSat; provides FlatSat facility requirements, access roles and responsibilities; and, and discusses FlatSat mechanical and electrical integration and functional testing.

  12. ACT/SAT College Survey.

    ERIC Educational Resources Information Center

    Stafford, John E.

    1998-01-01

    Reports on findings of a survey designed to discover whether higher education institutions' admission standards accept SAT I or ACT and if there is preference for either, and whether ACT could be submitted in lieu of SAT II subject tests. Eighty-six percent of the reporting schools indicated no preference; 28 schools indicated that the ACT was an…

  13. Experimental Insights into the Sulfuric Acid/Water Phase Diagram: Implications for Polar Stratospheric Clouds

    NASA Astrophysics Data System (ADS)

    Beyer, K. D.; Hansen, A. R.

    2002-05-01

    We have investigated the H2SO4/H2O binary liquid/solid phase diagram using a highly sensitive differential scanning calorimeter (DSC) and infrared spectroscopy of thin films. In particular we have sought to investigate the region from pure ice to sulfuric acid hemihexahydrate (SAH, H2SO4ú6.5H2O), including a detailed look at the sulfuric acid octahydrate (SAO). Our studies have found that there is a unique, repeatable IR spectra for SAO, which is not merely a combination of spectra of ice and sulfuric acid tetrahydrate (SAT), as has been previously suggested could be the case. From our DSC studies, we have identified the melting, or solid/solid phase transition of the octahydrate. We have also determined from our studies using the energy of fusion for SAO that SAO is a major component of H2SO4 solutions in the range 20 - 40 wt.% when they freeze. Our results indicate that SAO could be a significant portion of solid or partially frozen polar stratospheric cloud particles. As such, key stratospheric reactions should be studied on SAO surfaces.

  14. NASA Facts: SporeSat

    NASA Technical Reports Server (NTRS)

    Martinez, Andres; Cappuccio, Gelsomina; Tomko, David

    2013-01-01

    SporeSat is an autonomous, free-flying three-unit (3U) spacecraft that will be used to conduct scientific experiments to gain a deeper knowledge of the mechanisms of plant cell gravity sensing. SporeSat is being developed through a partnership between NASAs Ames Research Center and the Department of Agricultural and Biological Engineering at Purdue University. Amani Salim and Jenna L. Rickus are the Purdue University Principal Investigators. The SporeSat mission will be flown using a 3U nanosatellite weighing approximately 12 pounds and measuring 14 inches long by 4 inches wide by 4 inches tall. SporeSat will utilize flight-proven spacecraft technologies demonstrated on prior Ames nanosatellite missions such as PharmaSat and OrganismOrganic Exposure to Orbital Stresses (OOREOS) as well as upgrades that increase the hardware integration capabilities with SporeSat science instrumentation. In addition, the SporeSat science payload will serve as a technology platform to evaluate new microsensor technologies for enabling future fundamental biology missions.

  15. SATS HVO Concept Validation Experiment

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria; Williams, Daniel; Murdoch, Jennifer; Adams, Catherine

    2005-01-01

    A human-in-the-loop simulation experiment was conducted at the NASA Langley Research Center s (LaRC) Air Traffic Operations Lab (ATOL) in an effort to comprehensively validate tools and procedures intended to enable the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept of operations. The SATS HVO procedures were developed to increase the rate of operations at non-towered, non-radar airports in near all-weather conditions. A key element of the design is the establishment of a volume of airspace around designated airports where pilots accept responsibility for self-separation. Flights operating at these airports, are given approach sequencing information computed by a ground based automated system. The SATS HVO validation experiment was conducted in the ATOL during the spring of 2004 in order to determine if a pilot can safely and proficiently fly an airplane while performing SATS HVO procedures. Comparative measures of flight path error, perceived workload and situation awareness were obtained for two types of scenarios. Baseline scenarios were representative of today s system utilizing procedure separation, where air traffic control grants one approach or departure clearance at a time. SATS HVO scenarios represented approaches and departure procedures as described in the SATS HVO concept of operations. Results from the experiment indicate that low time pilots were able to fly SATS HVO procedures and maintain self-separation as safely and proficiently as flying today's procedures.

  16. Spectral, mechanical, thermal, optical and solid state parameters, of metal-organic bis(hydrogenmaleate)-CO(II) tetrahydrate crystal

    SciTech Connect

    Chandran, Senthilkumar; Jagan, R.; Paulraj, Rajesh; Ramasamy, P.

    2015-10-15

    Metal-organic bis(hydrogenmaleate)-Co(II) tetrahydrate single crystals have been grown by slow evaporation solution growth technique at room temperature. The crystal structure and the unit cell parameters were analyzed from the X-ray diffraction studies. Single-crystal X-ray diffraction analyses reveal that the grown crystal belongs to triclinic system with the space group P-1. Functional groups in bis(hydrogenmaleate)-Co(II) tetrahydrate were identified by Fourier transform infrared spectral analysis. The peak observed at 663 cm{sup −1} is assigned to the (Co–O) stretching vibrations. The optical transmission of the crystal was studied by UV–vis–NIR spectral analysis. The photoluminescence emission studies were carried out for the title compound in a wide wavelength range between 350 nm and 550 nm at 303 K. Mechanical strength was tested by Vickers microhardness test. The laser damage threshold value has been determined using Nd:YAG laser operating at 1064 nm. At various frequencies and temperatures the dielectric behavior of the material was investigated. Solid state parameters such as plasma energy, Penn gap, Fermi energy and electronic polarizability were evaluated. Photoconductivity measurements were carried out for the grown crystal in the presence of DC electric field at room temperature. Thermal stability and decomposition of the crystal were studied by TG–DTA. The weight loss of the title compound occurs in different steps. - Graphical abstract: Molecular structure of the bis(hydrogenmaleate)-Co(II) tetrahydrate drawn at 40% ellipsoid probability level. - Highlights: • Bis(hydrogenmaleate)-Co(II) tetrahydrate single crystal is grown by slow evaporation method. • Structural and optical properties were discussed. • The title complex crystal is thermally stable up to 91 °C. • Plasma energy, Fermi energy and electronic polarizability are evaluated. • It exhibits positive photoconductivity.

  17. COLD-SAT dynamic model

    NASA Astrophysics Data System (ADS)

    Adams, Neil S.; Bollenbacher, Gary

    1992-12-01

    This report discusses the development and underlying mathematics of a rigid-body computer model of a proposed cryogenic on-orbit liquid depot storage, acquisition, and transfer spacecraft (COLD-SAT). This model, referred to in this report as the COLD-SAT dynamic model, consists of both a trajectory model and an attitudinal model. All disturbance forces and torques expected to be significant for the actual COLD-SAT spacecraft are modeled to the required degree of accuracy. Control and experimental thrusters are modeled, as well as fluid slosh. The model also computes microgravity disturbance accelerations at any specified point in the spacecraft. The model was developed by using the Boeing EASY5 dynamic analysis package and will run on Apollo, Cray, and other computing platforms.

  18. COLD-SAT dynamic model

    NASA Technical Reports Server (NTRS)

    Adams, Neil S.; Bollenbacher, Gary

    1992-01-01

    This report discusses the development and underlying mathematics of a rigid-body computer model of a proposed cryogenic on-orbit liquid depot storage, acquisition, and transfer spacecraft (COLD-SAT). This model, referred to in this report as the COLD-SAT dynamic model, consists of both a trajectory model and an attitudinal model. All disturbance forces and torques expected to be significant for the actual COLD-SAT spacecraft are modeled to the required degree of accuracy. Control and experimental thrusters are modeled, as well as fluid slosh. The model also computes microgravity disturbance accelerations at any specified point in the spacecraft. The model was developed by using the Boeing EASY5 dynamic analysis package and will run on Apollo, Cray, and other computing platforms.

  19. DebriSat Project Update and Planning

    NASA Technical Reports Server (NTRS)

    Sorge, M.; Krisko, P. H.

    2016-01-01

    DebriSat Reporting Topics: DebriSat Fragment Analysis Calendar; Near-term Fragment Extraction Strategy; Fragment Characterization and Database; HVI (High-Velocity Impact) Considerations; Requirements Document.

  20. Solubility of triuranyl diphosphate tetrahydrate (TDT) and Na autunite at 23 and 50 degrees C

    SciTech Connect

    Armstrong, Christopher R.; Felmy, Andrew R.; Clark, Sue B.

    2010-11-01

    In this report we present experimental solubility data for well-characterized triuranyl diphosphate tetrahydrate (TDT: (UO2)(3)(PO4)(2)center dot 4H(2)O) and Na autunite (Na[UO2PO4]center dot xH(2)O) at 23 and 50 degrees C in NaClO4-HClO4 solutions at pC(H+) = 2. Duplicate samples of TDT in 0.1, 0.5, 1.0, 2.0 and 5.0 in solutions were equilibrated at 23 and 50 degrees C. TDT solid was synthesized and characterized with ICP-OES, ATR-IR and powder XRD before and after solubility experiments. The pH of the suspensions were monitored throughout the experiments. Equilibrium was achieved from undersaturation with respect to TDT and oversaturation for Na autunite. Steady-state conditions were achieved in all cases within 82 d. TDT was unstable at ionic strengths above 0.1 m, where its complete conversion to Na autunite was observed. The ion-interaction model was used to interpret the experimental solubility data. The solubility product, log K-sp, for TDT was determined to be -49.7 and -51.3 at 23 and 50 degrees C respectively. log K for Na autunite was determined to be -24.4 (23 degrees C) and -24.1 +/- 0.2 (50 degrees C).

  1. Study of rare-earth fluoride oxalate tetrahydrates by IR spectroscopy

    SciTech Connect

    Pushkina, G.Ya.; Kizhlo, M.R.; Komissarova, L.N.; Shatskii, V.M.

    1987-01-01

    The IR spectra of ..cap alpha..-LnC/sub 2/O/sub 4/F x 4H/sub 2/O (Ln = Tb, Dy, Ho, Y) and ..beta..-LnC/sub 2/O/sub 4/F x 4H/sub 2/O (Ln = Tb-Lu, Y) and their deuteration products have been studied. The structural features of these fluoride oxalate tetrahydrates have been discussed on the basis of a comparison of data from IR and PMR spectroscopy and a complex thermal analysis. It has been shown that the ..cap alpha.. and ..beta.. modifications differ with respect to the coordination of the water molecules. In ..beta..-LnC/sub 2/O/sub 4/F x 4H/sub 2/O two H/sub 2/O molecules are coordinated by the metal, and the remaining water participates in the creation of a system of strong hydrogen bonds. In ..cap alpha..-LnC/sub 2/O/sub 4/F x 4H/sub 2/O the character of the coordination of the H/sub 2/O molecules is more complicated, at least three different types of water molecules can be identified, and more than two water molecules are probably coordinated by the metal. The type of coordination of the oxalato groups in the compounds has been discussed.

  2. EMC Test Report: StangSat - CubeSat Program

    NASA Technical Reports Server (NTRS)

    Carmody, Lynne M.; Aragona, Peter S.

    2013-01-01

    This report documents the Electromagnetic Interference E M I testing performed on the StangSat; the unit under test (UUT). Testing was per the requirements of MIL STD-461F. The UUT was characterized and passed the radiated emissions (RE102 limit for Spacecraft) testing.

  3. What Have the Pilot SATs Taught Us?

    ERIC Educational Resources Information Center

    Pearson, Lea

    1990-01-01

    This paper describes pilot testing of Great Britain's standard assessment tasks (SATs), focusing on children with special educational needs. Two SATs were produced (Change and Movement) to assess three core subjects (English, mathematics, and science.) The need for SAT adaptations to allow children with disabilities equal access is stressed. (JDD)

  4. Tensor Network Contractions for #SAT

    NASA Astrophysics Data System (ADS)

    Biamonte, Jacob D.; Morton, Jason; Turner, Jacob

    2015-09-01

    The computational cost of counting the number of solutions satisfying a Boolean formula, which is a problem instance of #SAT, has proven subtle to quantify. Even when finding individual satisfying solutions is computationally easy (e.g. 2-SAT, which is in ), determining the number of solutions can be #-hard. Recently, computational methods simulating quantum systems experienced advancements due to the development of tensor network algorithms and associated quantum physics-inspired techniques. By these methods, we give an algorithm using an axiomatic tensor contraction language for n-variable #SAT instances with complexity where c is the number of COPY-tensors, g is the number of gates, and d is the maximal degree of any COPY-tensor. Thus, n-variable counting problems can be solved efficiently when their tensor network expression has at most COPY-tensors and polynomial fan-out. This framework also admits an intuitive proof of a variant of the Tovey conjecture (the r,1-SAT instance of the Dubois-Tovey theorem). This study increases the theory, expressiveness and application of tensor based algorithmic tools and provides an alternative insight on these problems which have a long history in statistical physics and computer science.

  5. Independent Schools and the SAT

    ERIC Educational Resources Information Center

    Torres, Amada

    2016-01-01

    In September 2015, when the College Board released its average SAT scores for the 2015 graduating class, two details stood out for many educators: (1) the record participation and diversity numbers (close to 1.7 million students took the test, with 50 percent being students of color); and (2) the test's lower average scores compared with previous…

  6. SAT Future: Alignment to Standards

    ERIC Educational Resources Information Center

    Gewertz, Catherine

    2012-01-01

    One of the chief architects of the Common Core State Standards was named the next president of the College Board and said one of his top priorities is to reshape the organization's influential college-admissions test, the SAT, to better reflect the new standards. David Coleman will assume his new duties on Oct. 15, replacing Gaston Caperton, who…

  7. Properties of the Sodium Naproxen-Lactose-Tetrahydrate Co-Crystal upon Processing and Storage.

    PubMed

    Sovago, Ioana; Wang, Wenbo; Qiu, Danwen; Raijada, Dhara; Rantanen, Jukka; Grohganz, Holger; Rades, Thomas; Bond, Andrew D; Löbmann, Korbinian

    2016-01-01

    Co-crystals and co-amorphous systems are two strategies to improve the physical properties of an active pharmaceutical ingredient and, thus, have recently gained considerable interest both in academia and the pharmaceutical industry. In this study, the behavior of the recently identified sodium naproxen-lactose-tetrahydrate co-crystal and the co-amorphous mixture of sodium, naproxen, and lactose was investigated. The structure of the co-crystal is described using single-crystal X-ray diffraction. The structural analysis revealed a monoclinic lattice, space group P21, with the asymmetric unit containing one molecule of lactose, one of naproxen, sodium, and four water molecules. Upon heating, it was observed that the co-crystal transforms into a co-amorphous system due to the loss of its crystalline bound water. Dehydration and co-amorphization were studied using synchrotron X-ray radiation and thermogravimetric analysis (TGA). Subsequently, different processing techniques (ball milling, spray drying, and dehydration) were used to prepare the co-amorphous mixture of sodium, naproxen, and lactose. X-ray powder diffraction (XRPD) revealed the amorphous nature of the mixtures after preparation. Differential scanning calorimetry (DSC) analysis showed that the blends were single-phase co-amorphous systems as indicated by a single glass transition temperature. The samples were subsequently tested for physical stability under dry (silica gel at 25 and 40 °C) and humid conditions (25 °C/75% RH). The co-amorphous samples stored at 25 °C/75% RH quickly recrystallized into the co-crystalline state. On the other hand, the samples stored under dry conditions remained physically stable after five months of storage, except the ball milled sample stored at 40 °C which showed signs of recrystallization. Under these dry conditions, however, the ball-milled co-amorphous blend crystallized into the individual crystalline components. PMID:27104502

  8. [A Low-temperature Manganese Chloride Tetrahydrate Improves the Image Quality of Magnetic Resonance Cholangiopancreatography].

    PubMed

    Watanabe, Kunihiro; Ishimori, Yoshiyuki; Sakurai, Hitoshi; Iwai, Yuji; Miida, Kazuo; Kurita, Kouki

    2016-04-01

    Manganese chloride tetrahydrate (MCT) is one of the oral negative contrast agents which is indispensable for imaging of magnetic resonance cholangiopancreatography (MRCP). In this study, improvement of the image quality of MRCP by using low-temperature MCT is verified. All MR imagings were performed using 1.5 T scanner. The T(1) and T(2) values of the different temperature MCTs were measured in the phantom study. Different concentrations of MCT-doped water (30%, 50%, 70%, and 90%) were measured at several temperature conditions (10°C, 15°C, 23°C, 35°C, and 40°C). As a result, the T(1) and T(2) values became larger with a temperature rise. It was more remarkable in low-concentration MCT. Then, 17 healthy subjects were scanned two times with different temperatures of MCT. The MCT of the normal temperature (23°C) and low temperature (10°C) were taken at consecutive 2 days. The contrast between the stomach and the spleen were significantly higher in 2D half Fourier acquisition single shot turbo spin echo (HASTE) images by use of the low-temperature MCT. The contrast between the common bile duct and the adjacent background were significantly higher in the source images of 3D MRCP by use of the low temperature MCT. In addition, 76% of subjects answered in the questionnaire that the low temperature MCT is easier to drink. The low temperature MCT improves the image quality of MRCP and contributes to performing noninvasive examination. PMID:27097992

  9. CS2SAT Desktop Tool

    2006-03-15

    The Idaho National Laboratory (INL) has developed a Control System Cyber Security Self-Assessment Tool (CS2SAT) desktop tool that provides a repeatable and systematic approach for control system users to assess the cyber security posture of their control system networks. The tool assists users in identifying the cyber security parameters of their systems and then offers security objectives, in the form of requirements, for improving the security of their specific network. Each requirement is linked tomore » a series of associated recommendations for compliance dependent upon the desired level of security protection. Each requirement is supported by links to the original standards document and recommendations are supported by links to whitepapers and other help documents. Package also includes two back-end supporting codes: CS2SAT Requirements Matrix and Control System Security Information System.« less

  10. The COLD-SAT program

    NASA Technical Reports Server (NTRS)

    Bailey, William J.

    1990-01-01

    The Cryogenic On-Orbit Liquid Depot Storage, Acquisition and Transfer (COLD-SAT) satellite is an experimental spacecraft launched from an expendable launch vehicle which is designed to investigate the systems and technologies required for efficient and reliable management of cryogenic fluid in the reduced-gravity space environment. Future applications such as Space Station, Space Transportation Vehicle (STV), external tank (ET), aft cargo carrier (ACC) propellant scavenging, storage depots, and lunar and interplanetary missions, among others, have provided the impetus to pursue this technology in a timely manner to support the design efforts. A refined conceptual approach has been developed and an overview of the COLD-SAT program is described which includes the following: (1) a definition of the technology needs and the accompanying experimental six-month baseline mission; (2) a description of the experiment subsystem, major features, and rationale for satisfaction of primary and secondary experiment requirements using LH2 as the test fluid; and (3) a presentation of the conceptual design of the COLD-SAT spacecraft subsystems which support the on-orbit experiment with emphasis on those areas which posed the greatest technical challenge.

  11. Spectral, mechanical, thermal, optical and solid state parameters, of metal-organic bis(hydrogenmaleate)-CO(II) tetrahydrate crystal

    NASA Astrophysics Data System (ADS)

    Chandran, Senthilkumar; Jagan, R.; Paulraj, Rajesh; Ramasamy, P.

    2015-10-01

    Metal-organic bis(hydrogenmaleate)-Co(II) tetrahydrate single crystals have been grown by slow evaporation solution growth technique at room temperature. The crystal structure and the unit cell parameters were analyzed from the X-ray diffraction studies. Single-crystal X-ray diffraction analyses reveal that the grown crystal belongs to triclinic system with the space group P-1. Functional groups in bis(hydrogenmaleate)-Co(II) tetrahydrate were identified by Fourier transform infrared spectral analysis. The peak observed at 663 cm-1 is assigned to the (Co-O) stretching vibrations. The optical transmission of the crystal was studied by UV-vis-NIR spectral analysis. The photoluminescence emission studies were carried out for the title compound in a wide wavelength range between 350 nm and 550 nm at 303 K. Mechanical strength was tested by Vickers microhardness test. The laser damage threshold value has been determined using Nd:YAG laser operating at 1064 nm. At various frequencies and temperatures the dielectric behavior of the material was investigated. Solid state parameters such as plasma energy, Penn gap, Fermi energy and electronic polarizability were evaluated. Photoconductivity measurements were carried out for the grown crystal in the presence of DC electric field at room temperature. Thermal stability and decomposition of the crystal were studied by TG-DTA. The weight loss of the title compound occurs in different steps.

  12. The New SAT: The Future of Transition Assessment.

    ERIC Educational Resources Information Center

    Graff, A. Steven

    1993-01-01

    Describes changes being made in the Scholastic Aptitude Test (SAT) and other standardized tests. Highlights include a history of standardized college entrance testing; the change process of the SAT; descriptions of the new SAT I Reasoning Tests and SAT II Subject Tests; comparisons between the old and the new SAT; and future possibilities. (LRW)

  13. Improving Resource-Unaware SAT Solvers

    NASA Astrophysics Data System (ADS)

    Hölldobler, Steffen; Manthey, Norbert; Saptawijaya, Ari

    The paper discusses cache utilization in state-of-the-art SAT solvers. The aim of the study is to show how a resource-unaware SAT solver can be improved by utilizing the cache sensibly. The analysis is performed on a CDCL-based SAT solver using a subset of the industrial SAT Competition 2009 benchmark. For the analysis, the total cycles, the resource stall cycles, the L2 cache hits and the L2 cache misses are traced using sample based profiling. Based on the analysis, several techniques - some of which have not been used in SAT solvers so far - are proposed resulting in a combined speedup up to 83% without affecting the search path of the solver. The average speedup on the benchmark is 60%. The new techniques are also applied to MiniSAT2.0 improving its runtime by 20% on average.

  14. A Case for Not Going SAT-Optional: Students with Discrepant SAT and HSGPA Performance

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Shaw, Emily J.; Kobrin, Jennifer L.

    2010-01-01

    Presented at the national conference for the American Educational Research Association (AERA) in 2010. This presentation describes an alternative way of presenting the unique information provided by the SAT over HSGPA, namely examining students with discrepant SAT-HSGPA performance.

  15. Different Tests, Same Flaws: Examining the SAT I, SAT II, and ACT

    ERIC Educational Resources Information Center

    Perez, Christina

    2002-01-01

    Spurred in part by University of California (UC) President Richard Atkinson's February 2001 proposal to drop the SAT I for UC applicants, more attention is being paid to other tests such as the SAT II and ACT. Proponents of these alternative exams argue that the SAT I is primarily an aptitude test measuring some vague concept of "inherent…

  16. A Small Aircraft Transportation System (SATS) Demand Model

    NASA Technical Reports Server (NTRS)

    Long, Dou; Lee, David; Johnson, Jesse; Kostiuk, Peter; Yackovetsky, Robert (Technical Monitor)

    2001-01-01

    The Small Aircraft Transportation System (SATS) demand modeling is a tool that will be useful for decision-makers to analyze SATS demands in both airport and airspace. We constructed a series of models following the general top-down, modular principles in systems engineering. There are three principal models, SATS Airport Demand Model (SATS-ADM), SATS Flight Demand Model (SATS-FDM), and LMINET-SATS. SATS-ADM models SATS operations, by aircraft type, from the forecasts in fleet, configuration and performance, utilization, and traffic mixture. Given the SATS airport operations such as the ones generated by SATS-ADM, SATS-FDM constructs the SATS origin and destination (O&D) traffic flow based on the solution of the gravity model, from which it then generates SATS flights using the Monte Carlo simulation based on the departure time-of-day profile. LMINET-SATS, an extension of LMINET, models SATS demands at airspace and airport by all aircraft operations in US The models use parameters to provide the user with flexibility and ease of use to generate SATS demand for different scenarios. Several case studies are included to illustrate the use of the models, which are useful to identify the need for a new air traffic management system to cope with SATS.

  17. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores.

    PubMed

    Hannon, Brenda

    2012-11-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors. PMID:23997382

  18. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores

    PubMed Central

    Hannon, Brenda

    2013-01-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors. PMID:23997382

  19. Computer as a Tool in SAT Preparation.

    ERIC Educational Resources Information Center

    Coffin, Gregory C.

    Two experimental programs, designed to increase Scholastic Aptitude Test (SAT) scores of inner city, low achieving students by using computer-assisted SAT preparation, produced differing results. Forty volunteers from a nearby high school were assigned to two groups of 20 each--one experimental and one control group. The first program provided six…

  20. Ace the Verbal on the SAT

    ERIC Educational Resources Information Center

    Meierding, Loren

    2005-01-01

    Many students are not accepted in to certain colleges and universities because of low SAT scores. Loren Meierding has written Ace the Verbal on the SAT to help students with minimal preparation do well by improving their vocabulary and use better techniques for finding the answers to the questions. This book provides strategies needed to score…

  1. Colleges Making SAT Optional as Admissions Requirement

    ERIC Educational Resources Information Center

    Gilroy, Marilyn

    2007-01-01

    This article reports that more colleges are dropping the SAT as a requirement for admission and, in many cases, these institutions are attracting a larger and more diverse pool of applicants. According to the National Center for Fair & Open Testing (FairTest), 740 schools have made the SATs optional. The list includes some of the nation's most…

  2. Space Environmental NanoSat Experiment (SENSE)

    NASA Astrophysics Data System (ADS)

    Kalamaroff, K. I.; Thompson, D. C.; Gentile, L. C.; Cooke, D. L.; Bonito, N.; La Tour, P.

    2012-12-01

    The Space Environmental NanoSat Experiment (SENSE) program is a rapid development effort of the USAF Space and Missiles Center Development Planning Directorate (SMC/XR) which will demonstrate the capability of NanoSats to perform space missions in an affordable and resilient manner. The three primary objectives for the SENSE mission are: 1) to develop best practices for operational CubeSat/NanoSat procurement, development, test, and operations; 2) to mature CubeSat bus and sensor component technology readiness levels; and 3) to demonstrate the operational utility of CubeSat measurements by flowing validated, low-latency data into operational space weather models. SENSE consists of two 3-U CubeSats scheduled for launch in summer 2013. Both satellites are 3-axis stabilized with star cameras for attitude determination and are equipped with a Compact Total Electron Density Sensor (CTECS) to provide radio occultation measurements of total electron content and L-band scintillation. One satellite has a Cubesat Tiny Ionospheric Photometer (CTIP) monitoring 135.6 nm photons produced by the recombination of O+ ions and electrons. The other satellite has a Wind Ion Neutral Composite Suite (WINCS) to acquire simultaneous co-located, in situ measurements of atmospheric and ionospheric density, composition, temperature and winds/drifts. Mission data will be used to improve current and future space weather models and demonstrate the utility of data from CubeSats for operational weather requirements.

  3. NextSat on-orbit experiences

    NASA Astrophysics Data System (ADS)

    Randall, Christopher R.; Porter, Bradley S.; Stokley, Catherine; Epstein, Kenneth; Kaufman, David

    2008-04-01

    The NextSat spacecraft was designed and built by Ball Aerospace & Technologies Corp. as part of the DARPA-funded Orbital Express mission. Orbital Express, launched in March of 2007, was a highly successful demonstration mission proving the feasibility of autonomous on-orbit refueling and servicing of spacecraft. The Orbital Express mission consisted of the Ball-built NextSat/CSC satellite and the Boeing-built ASTRO satellite. Both satellites launched mated into a 492km circular orbit on board a Lockheed-Martin Atlas V 401 launch vehicle from Cape Canaveral. The NextSat satellite acted as both the next generation "serviceable" satellite and the commodities satellite. This paper discusses the on-orbit mission experiences of the NextSat satellite. Key experiences include: launch and early orbit operations in which the NextSat satellite was called on to perform critical attitude control functions for the mated stack, functionality which was never tested or planned for; autonomous fluid transfers between ASTRO and NextSat; autonomous ORU transfers between ASTRO and NextSat; autonomous separation, free-flying and rendezvous operations; and end-of-life operations.

  4. Reentry Experiment SAT-X

    NASA Astrophysics Data System (ADS)

    Woods, Maurice; Kuhns, Casey; Honda, Motoaki; Shiely, Robert; Adamson, Aaron; Aken, Jordan; Walch, Robert; Galovich, Cynthia; Semak, Matthew

    2011-10-01

    The challenge of reentering the Earth's atmosphere is not new. For years, NASA has successfully designed vessels that have endured the harsh process of reentry. However, in most cases, this is made possible only through the act of over-engineering; designing to withstand conditions far beyond what is expected to be encountered. Though this method has been effective, there would be benefit in knowing more precisely what to expect upon atmospheric reentry. The University of Northern Colorado Reentry Experiment SAT-X project, launched from Wallops Island, Virginia on July 21, 2011, was designed to shed light on the reentry process by collecting motion data for a capsule ejected from a rocket. Moreover, a secondary objective was to test the capability of the prototype capsule to serve as a platform for future reentry experiments. The mission and preliminary results from the launch will be described.

  5. PhoneSat - The Smartphone Nanosatellite

    NASA Technical Reports Server (NTRS)

    Cockrell, James J.; Yost, Bruce; Petro, Andrew

    2013-01-01

    NASAs PhoneSat project will test whether spacecraft can be built using smartphones to launch the lowest-cost satellites ever flown in space. Each PhoneSat nanosatellite is one cubesat unit - a satellite in a 10 cm (approx. 4 inches) cube or about the size of a tissue box - and weighs approximately three pounds. Engineers believe PhoneSat technology will enable NASA to launch multiple new satellites capable of conducting science and exploration missions at a small fraction of the cost of conventional satellites.

  6. PhoneSat - The Smartphone Nanosatellite

    NASA Technical Reports Server (NTRS)

    Cockrell, James J.; Yost, Bruce; Petro, Andrew

    2013-01-01

    NASA's PhoneSat project tests whether spacecraft can be built using smartphones to launch the lowest-cost satellites ever flown in space. Each PhoneSat nanosatellite is one cubesat unit - a satellite in a 10 cm (approx. 4 inches) cube or about the size of a tissue box - and weighs approximately 1 kg (2.2 pounds). Engineers believe PhoneSat technology will enable NASA to launch multiple new satellites capable of conducting science and exploration missions at a small fraction of the cost of conventional satellites.

  7. SAT-Solving Based on Boundary Point Elimination

    NASA Astrophysics Data System (ADS)

    Goldberg, Eugene; Manolios, Panagiotis

    We study the problem of building structure-aware SAT-solvers based on resolution. In this study, we use the idea of treating a resolution proof as a process of Boundary Point Elimination (BPE). We identify two problems of using SAT-algorithms with Conflict Driven Clause Learning (CDCL) for structure-aware SAT-solving. We introduce a template of resolution based SAT-solvers called BPE-SAT that is based on a few generic implications of the BPE concept. BPE-SAT can be viewed as a generalization of CDCL SAT-solvers and is meant for building new structure-aware SAT-algorithms. We give experimental results substantiating the ideas of the BPE approach. In particular, to show the importance of structural information we compare an implementation of BPE-SAT and state-of-the-art SAT-solvers on narrow CNF formulas.

  8. HaloSat- A CubeSat to Study the Hot Galactic Halo

    NASA Astrophysics Data System (ADS)

    Kaaret, Philip

    We propose to develop, build, and fly HaloSat, a CubeSat capable of measuring the oxygen line emission from the hot Galactic halo. A dedicated CubeSat enables an instrument design and observing strategy to maximize the halo signal while minimizing foregrounds from solar wind charge exchange interactions within the solar system. We will use HaloSat to map the distribution of hot gas in the Milky Way and determine whether it fills an extended, and thus massive halo, or whether the halo is compact, and thus does not contribute significantly to the total mass of the Milky Way. HaloSat can be accomplished at modest cost using a CubeSat, a novel platform for space astrophysics missions. We will use a commercially available CubeSat bus and commercially available X-ray detectors to reduce development risk and minimize overall mission cost. HaloSat builds on the initiatives of GSFC/Wallops Flight Facility (WFF) in the development of CubeSats for low cost access to space and relies on the technical expertise of WFF personnel for spacecraft and mission design and operations. The team, from University of Iowa (UI), GSFC, Johns Hopkins, and CNRS (France), contains experts in X-ray detector development and data analysis and the astrophysics of hot plasmas and Galactic structure. The UI team will include a number of junior researchers (undergraduates, graduate students, and a postdoc) and help train them for future leadership roles on NASA space flight missions.

  9. CloudSat View of Flossie

    NASA Video Gallery

    CloudSat passed directly over Tropical Storm Flossie on July 29 and showed cumulus and stratocumulus clouds in northern Hawaii and cumulonimbus clouds over the southern part. Large amounts of liqui...

  10. Score Trends, SAT Validity and Subgroup Differences

    ERIC Educational Resources Information Center

    Camara, Wayne

    2008-01-01

    Presented at the Summer Institute on College Admissions at Harvard in June 2008. The presentation explores whether the SAT validity has changed with the test changes and if those changes affect specific subgroups.

  11. PhoneSat - The Smartphone Nanosatellite

    NASA Technical Reports Server (NTRS)

    Westley, Deborah; Yost, Bruce; Petro, Andrew

    2013-01-01

    PhoneSat 2.4, carried into space on November 19, 2013 aboard a Minotaur I rocket from the Mid-Atlantic Regional Spaceport at NASAs Wallops Flight Facility in Virginia, is the first of the PhoneSat family to use a two-way S-band radio to allow engineers to command the satellite from Earth. This mission also serves as a technology demonstration for a novel attitude determination and control system (ADCS) that establishes and stabilizes the satellites attitude relative to Earth. Unlike the earlier PhoneSats that used a Nexus One, PhoneSat 2.4 uses the Nexus S smartphone, which runs Googles Android operating system, and is made by Samsung Electronics Co., Suwon, So. Korea. The smartphone provides many of the functions needed by the satellite such as a central computer, data memory, ready-made interfaces for communications, navigation and power all pre-assembled in a rugged electronics package.

  12. The SAT: An Essay in Uncertainty

    ERIC Educational Resources Information Center

    Mlodinow, Leonard

    2008-01-01

    In this article, the author talks about the release of the most comprehensive study of SAT exams. The headline on the Web site of the College Board, the maker of the test, was, "SAT Studies Show Test's Strength in Predicting College Success." At the same time, a headline on the Web site of the group FairTest, a 23-year-old, nonprofit watchdog…

  13. Growth, crystalline perfection and characterization of Hexaaquanickel(II) dipotassium tetrahydrogen tetra-o-phthalate tetrahydrate crystals

    NASA Astrophysics Data System (ADS)

    Muthu, K.; Bhagavannarayana, G.; Meenakshisundaram, SP

    Pale-green single crystals of hexaaquanickel(II) dipotassium tetrahydrogen tetra-o-phthalate tetrahydrate K2[Ni(H2O)6] (C8H5O4)4·4H2O (PNHP), of dimension ˜33 mm × 18 mm × 4 mm have been grown by slow evaporation solution growth technique (SEST) and modified Sankaranarayanan-Ramasamy (SR) method. The powder XRD profiles and FT-IR are used for identifying the material. The lattice parameters of the as-grown crystals obtained by single crystal X-ray diffraction analysis confirm the formulae. Lower optical cut-off at ˜300 nm and optical transparency in the visible region were observed. The structural perfection of the grown crystal has been analyzed for SEST and SR method grown crystals by high-resolution X-ray diffraction (HRXRD) rocking curves (DC). The DCs of both the specimens are asymmetric with respect to Bragg position and more of scattered intensity in the negative direction is indicative of predominantly vacancy defects. Interestingly, SR method grown crystal has a better crystalline perfection than the conventionally grown crystal. The dielectric, thermal and mechanical behaviors of the specimen were also studied.

  14. Growth, crystalline perfection and characterization of hexaaquanickel(II) dipotassium tetrahydrogen tetra-o-phthalate tetrahydrate crystals.

    PubMed

    Muthu, K; Bhagavannarayana, G; Meenakshisundaram, S P

    2012-06-15

    Pale-green single crystals of hexaaquanickel(II) dipotassium tetrahydrogen tetra-o-phthalate tetrahydrate K(2)[Ni(H(2)O)(6)] (C(8)H(5)O(4))(4)·4H(2)O (PNHP), of dimension ~33 mm × 18 mm × 4 mm have been grown by slow evaporation solution growth technique (SEST) and modified Sankaranarayanan-Ramasamy (SR) method. The powder XRD profiles and FT-IR are used for identifying the material. The lattice parameters of the as-grown crystals obtained by single crystal X-ray diffraction analysis confirm the formulae. Lower optical cut-off at ~300 nm and optical transparency in the visible region were observed. The structural perfection of the grown crystal has been analyzed for SEST and SR method grown crystals by high-resolution X-ray diffraction (HRXRD) rocking curves (DC). The DCs of both the specimens are asymmetric with respect to Bragg position and more of scattered intensity in the negative direction is indicative of predominantly vacancy defects. Interestingly, SR method grown crystal has a better crystalline perfection than the conventionally grown crystal. The dielectric, thermal and mechanical behaviors of the specimen were also studied. PMID:22446778

  15. O/OREOS Sat: Organism/Organic Exposure to Orbital Stresses

    NASA Astrophysics Data System (ADS)

    Ehrenfreund, Pascale; Quinn, R.; Mattioda, A.; Bramall, N.; Bryson, K.; Chittenden, J.; Ricco, A.; Squires, D.; Santos, O.; Minelli, G.; Defouw, G.; Friedericks, C.; Landis, D.

    O/OREOS Sat is the first triple-cubesat mission of the NASA Astrobiology Small Payloads pro-gram. O/OREOS Sat will reach an orbit of 680 km and operate for at least 6 months. Success criteria for this mission are to (1) demonstrate the opportunities available for small satellites in astrobiology/chemical science research programs, (2) measure the degradation of(bio)organic molecules in a variety of astrobiologically relevant space environments, (3) demonstrate the capability to simulate a variety of space environments using small satellites, and (4) develop a robust and capable new small-sat in-situ measurement technology: UV-visible spectroscopy us-ing the Sun as light source. O/OREOS Sat investigates the stability of organic material in space by exposing four classes of organic molecules to the space environment: amino acid, quinone, polycyclic aromatic hydrocarbon, and metallo-porphyrin. One of each specimen will be main-tained in four self-contained micro-environments. The main objectives are to use changes in UV and visible absorption spectra to quantitatively measure the effects upon organic specimens of the combined exposure to space radiation and UV and visible light while in relevant space environments. O/OREOS Sat is scheduled to launch in May 2010 from Kodiak, Alaska on a Minotaur IV rocket and we report on the first results on O/OREOS in orbit.

  16. KidSat: Image User's Manual

    NASA Technical Reports Server (NTRS)

    Way, JoBea; Andres, Paul; Baker, John; Goodson, Greg; Marshall, William; McGuire, John; Rackley, Kathleen; Stork, Elizabeth Jones; Yiu, Lisa

    1999-01-01

    The goal of KidSat was to provide young students with the opportunity to participate directly in the NASA space program and to enhance learning in the process. The KidSat pilot project was focused on using a color digital camera, mounted on the space shuttle, to take pictures of the Earth. These could be used to enhance middle school curricula. The project not only benefited middle school students, who were essentially the Science Team, responsible for deciding where to take pictures, but it also benefited high school students and undergraduates, who were essentially the Project Team, responsible for the development and implementation of the project. KidSat flew on three missions as part of the pilot project: STS-76, STS-81, and STS-86. This document describes the goals, project elements, results, and data for the three KidSat missions that made up the pilot program. It serves as a record for this pilot project and may be used as a reference for similar projects. It can also be a too] in using the data to its fullest extent. The KidSat Web page remains on-line at http://kidsat.jpl.nasa.gov/kidsat, and the images may be downloaded in their full resolution.

  17. TemperSAT: A new efficient fair-sampling random k-SAT solver

    NASA Astrophysics Data System (ADS)

    Fang, Chao; Zhu, Zheng; Katzgraber, Helmut G.

    The set membership problem is of great importance to many applications and, in particular, database searches for target groups. Recently, an approach to speed up set membership searches based on the NP-hard constraint-satisfaction problem (random k-SAT) has been developed. However, the bottleneck of the approach lies in finding the solution to a large SAT formula efficiently and, in particular, a large number of independent solutions is needed to reduce the probability of false positives. Unfortunately, traditional random k-SAT solvers such as WalkSAT are biased when seeking solutions to the Boolean formulas. By porting parallel tempering Monte Carlo to the sampling of binary optimization problems, we introduce a new algorithm (TemperSAT) whose performance is comparable to current state-of-the-art SAT solvers for large k with the added benefit that theoretically it can find many independent solutions quickly. We illustrate our results by comparing to the currently fastest implementation of WalkSAT, WalkSATlm.

  18. The Amma-Sat Database

    NASA Astrophysics Data System (ADS)

    Ramage, K.; Desbois, M.; Eymard, L.

    2004-12-01

    The African Monsoon Multidisciplinary Analysis project is a French initiative, which aims at identifying and analysing in details the multidisciplinary and multi-scales processes that lead to a better understanding of the physical mechanisms linked to the African Monsoon. The main components of the African Monsoon are: Atmospheric Dynamics, the Continental Water Cycle, Atmospheric Chemistry, Oceanic and Continental Surface Conditions. Satellites contribute to various objectives of the project both for process analysis and for large scale-long term studies: some series of satellites (METEOSAT, NOAA,.) have been flown for more than 20 years, ensuring a good quality monitoring of some of the West African atmosphere and surface characteristics. Moreover, several recent missions, and several projects will strongly improve and complement this survey. The AMMA project offers an opportunity to develop the exploitation of satellite data and to make collaboration between specialist and non-specialist users. In this purpose databases are being developed to collect all past and future satellite data related to the African Monsoon. It will then be possible to compare different types of data from different resolution, to validate satellite data with in situ measurements or numerical simulations. AMMA-SAT database main goal is to offer an easy access to satellite data to the AMMA scientific community. The database contains geophysical products estimated from operational or research algorithms and covering the different components of the AMMA project. Nevertheless, the choice has been made to group data within pertinent scales rather than within their thematic. In this purpose, five regions of interest where defined to extract the data: An area covering Tropical Atlantic and Africa for large scale studies, an area covering West Africa for mesoscale studies and three local areas surrounding sites of in situ observations. Within each of these regions satellite data are projected on

  19. Partitioning SAT Instances for Distributed Solving

    NASA Astrophysics Data System (ADS)

    Hyvärinen, Antti E. J.; Junttila, Tommi; Niemelä, Ilkka

    In this paper we study the problem of solving hard propositional satisfiability problem (SAT) instances in a computing grid or cloud, where run times and communication between parallel running computations are limited.We study analytically an approach where the instance is partitioned iteratively into a tree of subproblems and each node in the tree is solved in parallel.We present new methods for constructing partitions which combine clause learning and lookahead. The methods are incorporated into the iterative approach and its performance is demonstrated with an extensive comparison against the best sequential solvers in the SAT competition 2009 as well as against two efficient parallel solvers.

  20. Two CubeSats Deployed from the International Space Station

    NASA Video Gallery

    This movie of a CubeSat deployment from the International Space Station shows a compilation of photos taken by astronauts on May 16, 2016. The bottom-most CubeSat is the NASA-funded MinXSS CubeSat,...

  1. Overestimation Bias in Self-Reported SAT Scores

    ERIC Educational Resources Information Center

    Mayer, Richard E.; Stull, Andrew T.; Campbell, Julie; Almeroth, Kevin; Bimber, Bruce; Chun, Dorothy; Knight, Allan

    2007-01-01

    The authors analyzed self-reported SAT scores and actual SAT scores for five different samples of college students (N = 650). Students overestimated their actual SAT scores by an average of 25 points (SD = 81, d = 0.31), with 10% under-reporting, 51% reporting accurately, and 39% over-reporting, indicating a systematic bias towards over-reporting.…

  2. Issues of Validity of SAT Subject Test: Korean with Listening

    ERIC Educational Resources Information Center

    Lee, Saekyun H.; Han, Hyunjoo

    2007-01-01

    This study investigated some issues regarding the validity of the Scholastic Achievement Test (SAT) Subject Test: Korean with Listening. The SAT Korean has been administered just once a year since its inception in 1997. As of March 2006, it had been administered nine times. However, SAT foreign language tests are not as rigorously researched as…

  3. SAT Participation and Performance for the Class of 2014. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2014-01-01

    SAT participation and performance are milestones on the path to college and career readiness. This report provides the results for SAT participation and performance in Montgomery County (Maryland) Public Schools (MCPS) for the class of 2014. Analysis of postsecondary outcomes for MCPS graduates indicates that graduates who took the SAT were more…

  4. HaloSat - A CubeSat to Study the Hot Galactic Halo

    NASA Astrophysics Data System (ADS)

    Kaaret, Philip

    2016-04-01

    Observations of the nearby universe fail to locate about half of the normal matter (baryons) observed in the early universe. The missing baryons may be in hot galactic halos. HaloSat is a CubeSat designed to map oxygen line emission (O VII and O VIII) around the Milky Way in order to constrain the mass and spatial distribution of hot gas in the halo. HaloSat has a grasp competitive with current X-ray observatories. Its observing program will be optimized to minimize contributions from solar wind charge exchange (SWCX) emission that limit the accuracy of current measurements. We will describe the HaloSat mission concept, progress towards its implementation, and plans for archiving and distribution of the data.

  5. Generating Combinatorial Test Cases by Efficient SAT Encodings Suitable for CDCL SAT Solvers

    NASA Astrophysics Data System (ADS)

    Banbara, Mutsunori; Matsunaka, Haruki; Tamura, Naoyuki; Inoue, Katsumi

    Generating test cases for combinatorial testing is to find a covering array in Combinatorial Designs. In this paper, we consider the problem of finding optimal covering arrays by SAT encoding. We present two encodings suitable for modern CDCL SAT solvers. One is based on the order encoding that is efficient in the sense that unit propagation achieves the bounds consistency in CSPs. Another one is based on a combination of the order encoding and Hnich's encoding. CDCL SAT solvers have an important role in the latest SAT technology. The effective use of them is essential for enhancing efficiency. In our experiments, we found solutions that can be competitive with the previously known results for the arrays of strength two to six with small to moderate size of components and symbols. Moreover, we succeeded either in proving the optimality of known bounds or in improving known lower bounds for some arrays.

  6. Unflagged SATs: Who Benefits from Special Accommodations?

    ERIC Educational Resources Information Center

    Abrams, Samuel J.

    2005-01-01

    When the College Board announced, in the summer of 2002, that it would stop "flagging" the test scores of students who were given special accommodations for the SAT, the gold standard exam for college admission, disability advocates were thrilled. "A triumphant day for millions of people with dyslexia and other disabilities," exclaimed Thomas…

  7. Pre- to Post- CubeSats

    NASA Astrophysics Data System (ADS)

    Cutler, J.

    2015-12-01

    CubeSats sprung from a formative picosatellite effort at a university in the heart of Silicon Valley, took root in a university-led university environment, and have grown into complex-shaped explorers in both near and soon-to-be deep space. Private citizens, businesses, government are building and launching a variety of science, technology demonstration, and service missions. A new generation of space explorers is gaining first hand experience in space missions at all educational levels. There is new life and new energy in the space program. However, space is still difficult. The environment is harsh. Funding is sparse. This talk explores this history and the future of CubeSats from the context of a university-centric laboratory that emphasizes teaching, research, and entrepreneurial impact. It will explore the following questions: What sparked the CubeSat innovation? What are longer lasting lessons of this community? Where are places we can go next? What does it take to get there? The talk will draw on lessons learned from building over six on-orbit CubeSat missions and training hundreds of space engineers.

  8. The RadioSat (sm) network

    NASA Technical Reports Server (NTRS)

    Noreen, Gary K.

    1991-01-01

    The RadioSat network under development by radio Satellite Corporation will use mobile satellite (MSAT) technology to provide diverse personal communications, broadcast, and navigation services. The network will support these services simultaneously for integrated mobile radios throughout Canada and the United States. The RadioSat network takes advantage of several technological breakthroughs, all coming to fruition by the time the first MSAT satellite is launched in 1994. The most important of these breakthroughs is the enormous radiated power of each MSAT spacecraft - orders of magnitude greater than the radiated power of previous L-band spacecraft. Another important breakthrough is the development of advanced digital audio compression algorithms, enabling the transmission of broadcast quality music at moderate data rates. Finally, continuing dramatic increases in VLSI capabilities permit the production of complex, multi-function mobile satellite radios in very large quantities at prices little more than those of conventional car radios. In addition to performance breakthroughs and their economic implications to RadioSat, the design of the RadioSat network is reviewed.

  9. Investigating SATS-36 for a Matriculation Sample

    ERIC Educational Resources Information Center

    Krishnan, Saras; Idris, Noraini

    2015-01-01

    Students' attitudes towards statistics have been more often negative due to many factors such as initial perception of the subject, low ability in mathematics and lack of motivation to study statistics. Studies involving SATS-36 included investigation of the different factors in relation to students' attitude towards statistics. Other studies have…

  10. COLD-SAT Dynamic Model Computer Code

    NASA Technical Reports Server (NTRS)

    Bollenbacher, G.; Adams, N. S.

    1995-01-01

    COLD-SAT Dynamic Model (CSDM) computer code implements six-degree-of-freedom, rigid-body mathematical model for simulation of spacecraft in orbit around Earth. Investigates flow dynamics and thermodynamics of subcritical cryogenic fluids in microgravity. Consists of three parts: translation model, rotation model, and slosh model. Written in FORTRAN 77.

  11. SAT Scores at NAIS Member Schools

    ERIC Educational Resources Information Center

    Torres, Amada

    2015-01-01

    Between March and June 2014, more than 1.67 million students from the 2014 graduating class took the SAT, marking a new participation record for the test. At the request of the National Association of Independent Schools (NAIS), the College Board created a special report that allows the association to compare how independent school students fared…

  12. SAT's Next Chapter about to Be Written

    ERIC Educational Resources Information Center

    Honawar, Vaishali

    2005-01-01

    Starting in March 2005, the SAT, taken annually by more than 1.4 million college-bound students, will undergo its most significant change since 1994, when the College Board, which sponsors the test, first allowed calculators into test rooms, added open-ended math questions, and eliminated antonyms and added more critical-reading passages in the…

  13. SAT: a Late NS Protein of Porcine Parvovirus

    PubMed Central

    Zádori, Zoltán; Szelei, József; Tijssen, Peter

    2005-01-01

    The genomes of all members of the Parvovirus genus were found to contain a small open reading frame (ORF), designated SAT, with a start codon four or seven nucleotides downstream of the VP2 initiation codon. Green fluorescent protein or FLAG fusion constructs of SAT demonstrated that these ORFs were expressed. Although the SAT proteins of the different parvoviruses are not particularly conserved, they were all predicted to contain a membrane-spanning helix, and mutations in this hydrophobic stretch affected the localization of the SAT protein. SAT colocalized with calreticulin in the membranes of the endoplasmic reticulum and the nucleus. A knockout mutant (SAT−), with an unmodified VP sequence, showed a “slow-spreading” phenotype. These knockout mutants could be complemented with VP2− SAT+ mutant. The SAT protein is a late nonstructural (NS) protein, in contrast to previously identified NS proteins, since it is expressed from the same mRNA as VP2. PMID:16189014

  14. Achievements and Future Plan of Interplanetary CubeSats and Micro-Sats in Japan

    NASA Astrophysics Data System (ADS)

    Funase, Ryu

    2016-07-01

    This paper introduces Japanese achievements and future plans of CubeSats and Micro-Sats for deep space exploration. As the first step toward deep space mission by such tiny spacecraft, University of Tokyo and Japan Aerospace Exploration Agency (JAXA) developed the world's first deep space micro-spacecraft PROCYON (Proximate Object Close flYby with Optical Navigation). Its mission objective is to demonstrate a micro-spacecraft bus technology for deep space exploration and proximity flyby to asteroids performing optical measurements. PROCYON was launched into the Earth departure trajectory on December 3, 2014 together with Japanese asteroid sample return mission Hayabusa-2. PROCYON successfully completed the bus system demonstration mission in its interplanetary flight. Currently, Japan is not only pursuing the improvement and utilization of the demonstrated micro-sat deep space bus system with a weight of tens of kg or more for more practical scientific deep space missions, but also trying to develop smaller spacecraft with a weight of less than tens of kg, namely CubeSats, for deep space exploration. We are proposing a self-contained 6U CubeSat mission for the rideshare opportunity on the USA's SLS EM-1 mission, which will fly to a libration orbit around Earth-Moon L2 point and perform scientific observations of the Earth and the Moon. We are also seeking the possibility of CubeSats which is carried by a larger spacecraft to the destination and supports the mission by taking advantage of its low-cost and risk-tolerable feature. As an example of such style of CubeSat missions, we are studying a CubeSat for close observations of an asteroid, which will be carried to the target asteroid by a larger mother spacecraft. This CubeSat is released from the mother spacecraft to make a close flyby for scientific observations, which is difficult to be performed by the mother spacecraft if we consider the risk of the collision to the target asteroid or dust particles ejected

  15. COLD-SAT feasibility study safety analysis

    NASA Technical Reports Server (NTRS)

    Mchenry, Steven T.; Yost, James M.

    1991-01-01

    The Cryogenic On-orbit Liquid Depot-Storage, Acquisition, and Transfer (COLD-SAT) satellite presents some unique safety issues. The feasibility study conducted at NASA-Lewis desired a systems safety program that would be involved from the initial design in order to eliminate and/or control the inherent hazards. Because of this, a hazards analysis method was needed that: (1) identified issues that needed to be addressed for a feasibility assessment; and (2) identified all potential hazards that would need to be controlled and/or eliminated during the detailed design phases. The developed analysis method is presented as well as the results generated for the COLD-SAT system.

  16. SAT Encoding of Unification in EL

    NASA Astrophysics Data System (ADS)

    Baader, Franz; Morawska, Barbara

    Unification in Description Logics has been proposed as a novel inference service that can, for example, be used to detect redundancies in ontologies. In a recent paper, we have shown that unification in EL is NP-complete, and thus of a complexity that is considerably lower than in other Description Logics of comparably restricted expressive power. In this paper, we introduce a new NP-algorithm for solving unification problems in EL, which is based on a reduction to satisfiability in propositional logic (SAT). The advantage of this new algorithm is, on the one hand, that it allows us to employ highly optimized state-of-the-art SAT solvers when implementing an EL-unification algorithm. On the other hand, this reduction provides us with a proof of the fact that EL-unification is in NP that is much simpler than the one given in our previous paper on EL-unification.

  17. CubeSat deformable mirror demonstration

    NASA Astrophysics Data System (ADS)

    Cahoy, Kerri; Marinan, Anne; Kerr, Caitlin; Cheng, Kezi; Jamil, Sara

    2012-09-01

    The goal of the CubeSat Deformable Mirror Demonstration (DeMi) is to characterize the performance of a small deformable mirror over a year in low-Earth orbit. Small form factor deformable mirrors are a key technology needed to correct optical system aberrations in high contrast, high dynamic range space telescope applications such as space-based coronagraphic direct imaging of exoplanets. They can also improve distortions and reduce bit error rates for space-based laser communication systems. While follow-on missions can take advantage of this general 3U CubeSat platform to test the on-orbit performance of several different types of deformable mirrors, this first design accommodates a 32-actuator Boston Micromachines MEMS deformable mirror.

  18. ExoplanetSat: detecting transiting exoplanets using a low-cost CubeSat platform

    NASA Astrophysics Data System (ADS)

    Smith, Matthew W.; Seager, Sara; Pong, Christopher M.; Villaseñor, Jesus S.; Ricker, George R.; Miller, David W.; Knapp, Mary E.; Farmer, Grant T.; Jensen-Clem, Rebecca

    2010-07-01

    Nanosatellites, i.e. spacecraft that weigh between 1 and 10 kg, are drawing increasing interest as platforms for conducting on-orbit science. This trend is primarily driven by the ability to piggyback nanosatellites on the launch of large spacecraft and hence achieve orbit at greatly reduced cost. The CubeSat platform is a standardized nanosatellite configuration, consisting of one, two, or three 10 cm x 10 cm x 10 cm units (1, 2, or 3 "U"s) arranged in a row. We present a CubeSat-based concept for the discovery of transiting exoplanets around the nearest and brightest Sun-like stars. The spacecraft prototype - termed ExoplanetSat - is a 3U space telescope capable of monitoring a single target star from low Earth orbit. Given the volume limitations of the CubeSat form factor, designing a capable spacecraft requires overcoming significant challenges. This work presents the initial satellite configuration along with several subsystem-specific solutions to the aforementioned constraints. An optical design based on a modified commercial off-the-shelf camera lens is given. We also describe a novel two-stage attitude control architecture that combines 3-axis reaction wheels for coarse pointing with a piezoelectric translation stage at the focal plane for fine pointing. Modeling and simulation results are used to demonstrate feasibility by quantifying ExoplanetSat pointing precision, signal-to-noise ratio, guide star magnitude, and additional design parameters which determine system performance.

  19. Big Software for SmallSats: Adapting CFS to CubeSat Missions

    NASA Technical Reports Server (NTRS)

    Cudmore, Alan P.; Crum, Gary; Sheikh, Salman; Marshall, James

    2015-01-01

    Expanding capabilities and mission objectives for SmallSats and CubeSats is driving the need for reliable, reusable, and robust flight software. While missions are becoming more complicated and the scientific goals more ambitious, the level of acceptable risk has decreased. Design challenges are further compounded by budget and schedule constraints that have not kept pace. NASA's Core Flight Software System (cFS) is an open source solution which enables teams to build flagship satellite level flight software within a CubeSat schedule and budget. NASA originally developed cFS to reduce mission and schedule risk for flagship satellite missions by increasing code reuse and reliability. The Lunar Reconnaissance Orbiter, which launched in 2009, was the first of a growing list of Class B rated missions to use cFS. Large parts of cFS are now open source, which has spurred adoption outside of NASA. This paper reports on the experiences of two teams using cFS for current CubeSat missions. The performance overheads of cFS are quantified, and the reusability of code between missions is discussed. The analysis shows that cFS is well suited to use on CubeSats and demonstrates the portability and modularity of cFS code.

  20. LifeSat - A new research vehicle

    NASA Technical Reports Server (NTRS)

    Gilbreath, William P.; Dunning, Robert W.

    1990-01-01

    LifeSat is a reusable recoverable satellite that will support research in the gravitation and radiation biology fields. It can provide sustained lower gravitational levels than manned vehicles and can access orbits where specimens can be exposed to cosmic radiation. The satellite design encompasses environmental support for vertebrate, invertebrate and plant specimens ranging from cells and tissues up to small mammals. The first launch, in a series of 7 satellite flights, is planned for late 1995.

  1. A second order parameter for 3SAT

    SciTech Connect

    Sandholm, T.W.

    1996-12-31

    The 3-satisfiability problem (3SAT) has had a central role in the study of complexity. It was recently found that 3SAT instances transition sharply from satisfiable to nonsatisfiable as the ratio of clauses to variables increases. Because this phase transition is so sharp, the ratio - an order parameter - can be used to predict satisfiability. This paper describes a second order parameter for 3SAT. Like the classical order parameter, it can be computed in linear time, but it analyzes the structure of the problem instance more deeply. We present an analytical method for using this new order parameter in conjunction with the classical one to enhance satisfiability prediction accuracy. The assumptions of the method are verified by rigorous statistical testing. The method significantly increases the satisfiability prediction accuracy over using the classical order parameter alone. Hardness - i.e. how long it takes to determine satisfiability - results for one complete and one incomplete algorithm from the literature are also presented as a function of the two order parameters. The importance of new order parameters lies in the fact that they refine the locating of satisfiable vs. nonsatisfiable and hard vs. easy formulas in the space of all problem instances by adding a new dimension in the analysis.

  2. Physics First: Impact on SAT Math Scores

    NASA Astrophysics Data System (ADS)

    Bouma, Craig E.

    Improving science, technology, engineering, and mathematics (STEM) education has become a national priority and the call to modernize secondary science has been heard. A Physics First (PF) program with the curriculum sequence of physics, chemistry, and biology (PCB) driven by inquiry- and project-based learning offers a viable alternative to the traditional curricular sequence (BCP) and methods of teaching, but requires more empirical evidence. This study determined impact of a PF program (PF-PCB) on math achievement (SAT math scores) after the first two cohorts of students completed the PF-PCB program at Matteo Ricci High School (MRHS) and provided more quantitative data to inform the PF debate and advance secondary science education. Statistical analysis (ANCOVA) determined the influence of covariates and revealed that PF-PCB program had a significant (p < .05) impact on SAT math scores in the second cohort at MRHS. Statistically adjusted, the SAT math means for PF students were 21.4 points higher than their non-PF counterparts when controlling for prior math achievement (HSTP math), socioeconomic status (SES), and ethnicity/race.

  3. SAT Monitor Program. High School Students View the SAT and College Admissions Process. Report on Wave of Completed Questionnaires Associated with December 1977 SAT Administration.

    ERIC Educational Resources Information Center

    Response Analysis Corp., Princeton, NJ.

    College applicants taking the Scholastic Aptitude Test (SAT) and the Test of Standard Written English (TSWE) were surveyed regarding the tests, college admission in general, and the communications received concerning the test and their scores. Separate questionnaires were administered before taking the SAT or TSWE, after taking the test, and after…

  4. Advances in Ka-Band Communication System for CubeSats and SmallSats

    NASA Technical Reports Server (NTRS)

    Kegege, Obadiah; Wong, Yen F.; Altunc, Serhat

    2016-01-01

    A study was performed that evaluated the feasibility of Ka-band communication system to provide CubeSat/SmallSat high rate science data downlink with ground antennas ranging from the small portable 1.2m/2.4m to apertures 5.4M, 7.3M, 11M, and 18M, for Low Earth Orbit (LEO) to Lunar CubeSat missions. This study included link analysis to determine the data rate requirement, based on the current TRL of Ka-band flight hardware and ground support infrastructure. Recent advances in Ka-band transceivers and antennas, options of portable ground stations, and various coverage distances were included in the analysis. The link/coverage analysis results show that Cubesat/Smallsat missions communication requirements including frequencies and data rates can be met by utilizing Near Earth Network (NEN) Ka-band support with 2 W and high gain (>6 dBi) antennas.

  5. Big Software for SmallSats: Adapting cFS to CubeSat Missions

    NASA Technical Reports Server (NTRS)

    Cudmore, Alan P.; Crum, Gary Alex; Sheikh, Salman; Marshall, James

    2015-01-01

    Expanding capabilities and mission objectives for SmallSats and CubeSats is driving the need for reliable, reusable, and robust flight software. While missions are becoming more complicated and the scientific goals more ambitious, the level of acceptable risk has decreased. Design challenges are further compounded by budget and schedule constraints that have not kept pace. NASA's Core Flight Software System (cFS) is an open source solution which enables teams to build flagship satellite level flight software within a CubeSat schedule and budget. NASA originally developed cFS to reduce mission and schedule risk for flagship satellite missions by increasing code reuse and reliability. The Lunar Reconnaissance Orbiter, which launched in 2009, was the first of a growing list of Class B rated missions to use cFS.

  6. TechEdSat Nano-Satellite Series Fact Sheet

    NASA Technical Reports Server (NTRS)

    Murbach, Marcus; Martinez, Andres; Guarneros Luna, Ali

    2014-01-01

    TechEdSat-3p is the second generation in the TechEdSat-X series. The TechEdSat Series uses the CubeSat standards established by the California Polytechnic State University Cal Poly), San Luis Obispo. With typical blocks being constructed from 1-unit (1U 10x10x10 cm) increments, the TechEdSat-3p has a 3U volume with a 30 cm length. The project uniquely pairs advanced university students with NASA researchers in a rapid design-to-flight experience lasting 1-2 semesters.The TechEdSat Nano-Satellite Series provides a rapid platform for testing technologies for future NASA Earth and planetary missions, as well as providing students with an early exposure to flight hardware development and management.

  7. Finite-Size Scaling in Random K-SAT Problems

    NASA Astrophysics Data System (ADS)

    Ha, Meesoon; Lee, Sang Hoon; Jeon, Chanil; Jeong, Hawoong

    2010-03-01

    We propose a comprehensive view of threshold behaviors in random K-satisfiability (K-SAT) problems, in the context of the finite-size scaling (FSS) concept of nonequilibrium absorbing phase transitions using the average SAT (ASAT) algorithm. In particular, we focus on the value of the FSS exponent to characterize the SAT/UNSAT phase transition, which is still debatable. We also discuss the role of the noise (temperature-like) parameter in stochastic local heuristic search algorithms.

  8. Development of Novel Integrated Antennas for CubeSats

    NASA Technical Reports Server (NTRS)

    Jackson, David; Fink, Patrick W.; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Development of Novel Integrated Antennas for CubeSats project is directed at the development of novel antennas for CubeSats to replace the bulky and obtrusive antennas (e.g., whip antennas) that are typically used. The integrated antennas will not require mechanical deployment and thus will allow future CubeSats to avoid potential mechanical problems and therefore improve mission reliability. Furthermore, the integrated antennas will have improved functionality and performance, such as circular polarization for improved link performance, compared with the conventional antennas currently used on CubeSats.

  9. Validity of the SAT for Predicting First-Year Grades: 2008 SAT Validity Sample. Statistical Report No. 2011-5

    ERIC Educational Resources Information Center

    Patterson, Brian F.; Mattern, Krista D.

    2011-01-01

    The findings for the 2008 sample are largely consistent with the previous reports. SAT scores were found to be correlated with FYGPA (r = 0.54), with a magnitude similar to HSGPA (r = 0.56). The best set of predictors of FYGPA remains SAT scores and HSGPA (r = 0.63), as the addition of the SAT sections to the correlation of HSGPA alone with FYGPA…

  10. Selecting Students with a General Reasoning Test (SAT I) or Tests in Academic Subjects (SAT II): Does It Matter for Non-Native Speakers of English?

    ERIC Educational Resources Information Center

    Bridgeman, Brent; Burton, Nancy; Cline, Frederick

    Using data from a sample of 10 colleges at which most students had taken both the SAT I: Reasoning Test and SAT II: Subject Tests researchers simulated the effects of making selection decisions using SAT II scores in place of SAT I scores. Students in each college were treated as forming the applicant pool for a more select college, and the top…

  11. Characterization of monoclonal antibodies against a type SAT 2 foot-and-mouth disease virus.

    PubMed Central

    Crowther, J. R.; Rowe, C. A.; Butcher, R.

    1993-01-01

    This paper is the first to describe characterization of monoclonal antibodies (MAbs) against a South African Territories 2 (SAT 2) foot-and-mouth disease virus (isolate Rho 1/48). Twelve MAbs which neutralized homologous virus were characterized in indirect and sandwich ELISA using purified Rho 1/48 virus particles, subunits, trypsin-treated, and chemically denatured virus. All the MAbs inhibited haemagglutination by parental virus. Binding of the MAbs to 73 SAT 2 field isolates was measured in a sandwich ELISA and defined four distinct antigenic regions. Preliminary characterization of escape mutants selected with some of the MAbs using virus neutralization tests, ELISA, and amino acid sequencing is included. MAbs 2, 25, 40, 48 and 64, reacted with a linear epitope on the VP1 loop region. An amino acid change at position 149 (valine to glutamic acid) was detected in mutants selected by MAb 2 and 40 and this eliminated binding and neutralization by all the other MAb. This epitope was conformation-dependent and was conserved in all 73 isolates of SAT 2 examined. Escape mutants isolated with MAb 41 and 44, had changes at positions 156 (glycine to aspartic acid), or 158 (serine to leucine) respectively. These MAbs bound with Rho 1/48 only out of 73 field strain viruses studies and the reactions of MAbs from the other groups was unaltered. MAb 27, 28 and 37 reacted with a conformation-dependent epitope on VP1 which was not conserved in field isolates. All mutants selected by these MAbs had a single amino acid substitution at position 149 (valine to alanine). The same change was always found in field isolates which did not bind MAbs from this group. MAb 11 reacted with a linear epitope associated with amino acids 147 or 148 on VP1 and showed similar binding characteristics to a conformation dependent MAb 7, no amino acid residue changes were found within VP1 for monoclonal antibody 7 mutants. PMID:7691630

  12. Comparability of Scores on the New and Prior Versions of the SAT Reasoning Test™. Research Notes. RN-31

    ERIC Educational Resources Information Center

    Kobrin, Jennifer L.; Melican, Gerald J.

    2007-01-01

    This report synthesizes the research to date addressing the construct comparability of the SAT Reasoning Test and prior SAT I: Reasoning Test and the series of research studies addressing the equatability and subpopulation invariance of the SAT and SAT I.

  13. SAT-Based Model Checking without Unrolling

    NASA Astrophysics Data System (ADS)

    Bradley, Aaron R.

    A new form of SAT-based symbolic model checking is described. Instead of unrolling the transition relation, it incrementally generates clauses that are inductive relative to (and augment) stepwise approximate reachability information. In this way, the algorithm gradually refines the property, eventually producing either an inductive strengthening of the property or a counterexample trace. Our experimental studies show that induction is a powerful tool for generalizing the unreachability of given error states: it can refine away many states at once, and it is effective at focusing the proof search on aspects of the transition system relevant to the property. Furthermore, the incremental structure of the algorithm lends itself to a parallel implementation.

  14. The FedSat Microsatellite Mission

    NASA Astrophysics Data System (ADS)

    Fraser, B. J.

    2003-04-01

    An Australian research microsatellite, FedSat with a complement of four payloads was launched from Tanegashima, Japan on 14 December 2002 into a near-circular sun synchronous 10:30 LT polar orbit at an inclination of 98.7° and altitude 800 km. Scientific experiments include a triaxial fluxgate magnetometer with a frequency response up to 100 Hz and a GPS receiver to monitor total electron content (TEC) and provide a precise orbit determination. Communications experiments include a Ka-band transponder and a UHF packet data service. A high performance computer payload will test reconfigurable computing technology.

  15. Appraising the Implications of the SAT for Educational Policy.

    ERIC Educational Resources Information Center

    Steelman, Lala Carr; Powell, Brian

    1985-01-01

    Differences in the corrected state rankings on Scholastic Aptitude Test (SAT) scores are explained by the percentage of students taking the test and by student composition by sex, race, and average family income. Higher state per capita educational expenditures are significantly related to higher average SAT scores. Policy implications are…

  16. Money Improves Test Scores--Even State-Level SATs.

    ERIC Educational Resources Information Center

    Bracey, Gerald W.

    1996-01-01

    Three former secretaries of education--William Bennett, Lauro Cavazos, and Terrel Bell--have touted state-level SAT scores as proof that educational financing does not matter. Recently, Brian Powell and Lala Carr Steelman adjusted scores for participation rate and detected a very strong relationship between expenditures and SAT scores. Bigger…

  17. Variations in State SAT Performance: Meaningful or Misleading?

    ERIC Educational Resources Information Center

    Powell, Brian; Steelman, Lala Carr

    1984-01-01

    The authors attempt to show how the dissemination of uncorrected state Scholastic Aptitude Test (SAT) scores may have created an inaccurate public and governmental perception of the variation in educational quality. Their research demonstrates that comparing state SAT averages is ill-advised unless these ratings are corrected for compositional and…

  18. Mathematical SAT Test Scores and College Chemistry Grades.

    ERIC Educational Resources Information Center

    Spencer, Harry E.

    1996-01-01

    Explores the comparative performance of various segments of the student sample in general chemistry courses relative to their scores on the mathematical SAT test. Results indicate that mathematical skill measured by the SAT scores is an important factor in determining grades while factors that are not important in determining grades are gender…

  19. First-Year Chemistry Grades and SAT Math Scores.

    ERIC Educational Resources Information Center

    Andrews, Marjorie H.; Andrews, Lester

    1979-01-01

    Comparison of SAT math scores, high school grade point averages (GPAs), and final chemistry grades for both the 1972 and 1976 fall semester classes of the first-year chemistry course at the University of Virginia showed that SAT math scores were a much better predictor of final chemistry grades than were high school GPAs. (BB)

  20. Comparing State SAT Scores Using a Mixture Modeling Approach

    ERIC Educational Resources Information Center

    Kim, YoungKoung Rachel

    2009-01-01

    Presented at the national conference for AERA (American Educational Research Association) in April 2009. The large variability of SAT taker population across states makes state-by-state comparisons of the SAT scores challenging. Using a mixture modeling approach, therefore, the current study presents a method of identifying subpopulations in terms…

  1. The Revised SAT: No Better, No Worse at Its Job

    ERIC Educational Resources Information Center

    Hoover, Eric

    2008-01-01

    The latest word about the new SAT is this: It gives colleges about the same information as the old one did. Last week, the College Board announced that the recent changes in the SAT had not substantially altered how accurately it predicts first-year grades. The news prompted applause from the test's proponents, scorn from its critics, and little…

  2. CloudSat Anomaly Recovery and Operational Lessons Learned

    NASA Technical Reports Server (NTRS)

    Nayak, Michael; Witkowski, Mona

    2012-01-01

    Nov 2011: NASA/JPL declared CloudSat fully operational in DO ]OP Mode . CloudSat collects science data during sunlit portion of orbit, stable spin hibernation in eclipse . New CONOPS requires constant monitoring of thermal and power profiles, while allowing collection of 54 mins of science data per sunlit orbit

  3. CubeSat Integration into the Space Situational Awareness Architecture

    NASA Astrophysics Data System (ADS)

    Morris, K.; Wolfson, M.; Brown, J.

    2013-09-01

    Lockheed Martin Space Systems Company has recently been involved in developing GEO Space Situational Awareness architectures, which allows insights into how cubesats can augment the current national systems. One hole that was identified in the current architecture is the need for timelier metric track observations to aid in the chain of custody. Obtaining observations of objects at GEO can be supported by CubeSats. These types of small satellites are increasing being built and flown by government agencies like NASA and SMDC. CubeSats are generally mass and power constrained allowing for only small payloads that cannot typically mimic traditional flight capability. CubeSats do not have a high reliability and care must be taken when choosing mission orbits to prevent creating more debris. However, due to the low costs, short development timelines, and available hardware, CubeSats can supply very valuable benefits to these complex missions, affordably. For example, utilizing CubeSats for advanced focal plane demonstrations to support technology insertion into the next generation situational awareness sensors can help to lower risks before the complex sensors are developed. CubeSats can augment the planned ground and space based assets by creating larger constellations with more access to areas of interest. To aid in maintaining custody of objects, a CubeSat constellation at 500 km above GEO would provide increased point of light tracking that can augment the ground SSA assets. Key features of the Cubesat include a small visible camera looking along the GEO belt, a small propulsion system that allows phasing between CubeSats, and an image processor to reduce the data sent to the ground. An elegant communications network will also be used to provide commands to and data from multiple CubeSats. Additional CubeSats can be deployed on GSO launches or through ride shares to GEO, replenishing or adding to the constellation with each launch. Each CubeSat would take images of

  4. ProSAT+: visualizing sequence annotations on 3D structure.

    PubMed

    Stank, Antonia; Richter, Stefan; Wade, Rebecca C

    2016-08-01

    PRO: tein S: tructure A: nnotation T: ool-plus (ProSAT(+)) is a new web server for mapping protein sequence annotations onto a protein structure and visualizing them simultaneously with the structure. ProSAT(+) incorporates many of the features of the preceding ProSAT and ProSAT2 tools but also provides new options for the visualization and sharing of protein annotations. Data are extracted from the UniProt KnowledgeBase, the RCSB PDB and the PDBe SIFTS resource, and visualization is performed using JSmol. User-defined sequence annotations can be added directly to the URL, thus enabling visualization and easy data sharing. ProSAT(+) is available at http://prosat.h-its.org. PMID:27284084

  5. Massively Clustered CubeSats NCPS Demo Mission

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.; Young, David; Kim, Tony; Houts, Mike

    2013-01-01

    Technologies under development for the proposed Nuclear Cryogenic Propulsion Stage (NCPS) will require an un-crewed demonstration mission before they can be flight qualified over distances and time frames representative of a crewed Mars mission. In this paper, we describe a Massively Clustered CubeSats platform, possibly comprising hundreds of CubeSats, as the main payload of the NCPS demo mission. This platform would enable a mechanism for cost savings for the demo mission through shared support between NASA and other government agencies as well as leveraged commercial aerospace and academic community involvement. We believe a Massively Clustered CubeSats platform should be an obvious first choice for the NCPS demo mission when one considers that cost and risk of the payload can be spread across many CubeSat customers and that the NCPS demo mission can capitalize on using CubeSats developed by others for its own instrumentation needs. Moreover, a demo mission of the NCPS offers an unprecedented opportunity to invigorate the public on a global scale through direct individual participation coordinated through a web-based collaboration engine. The platform we describe would be capable of delivering CubeSats at various locations along a trajectory toward the primary mission destination, in this case Mars, permitting a variety of potential CubeSat-specific missions. Cameras on various CubeSats can also be used to provide multiple views of the space environment and the NCPS vehicle for video monitoring as well as allow the public to "ride along" as virtual passengers on the mission. This collaborative approach could even initiate a brand new Science, Technology, Engineering and Math (STEM) program for launching student developed CubeSat payloads beyond Low Earth Orbit (LEO) on future deep space technology qualification missions. Keywords: Nuclear Propulsion, NCPS, SLS, Mars, CubeSat.

  6. Substituting SAT II: Subject Tests for SAT I: Reasoning Tests: Impact on Admitted Class Composition and Quality.

    ERIC Educational Resources Information Center

    Bridgeman, Brent; Burton, Nancy; Cline, Frederick

    2003-01-01

    Simulated the effects of making admission decisions using SAT II subject scores in place of SAT I reasoning scores. Found that success rates, in terms of first-year grade point averages, were virtually identical for students selected by the different models. The percentage of African American, Asian American, and White students selected varied…

  7. An Application of Score Equity Assessment: Invariance of Linkage of New SAT[R] to Old SAT across Gender Groups

    ERIC Educational Resources Information Center

    Liu, Jinghua; Cahn, Miriam F.; Dorans, Neil J.

    2006-01-01

    The College Board's SAT[R] data are used to illustrate how the score equity assessment (SEA) can help inform the program about equatability. SEA is used to examine whether the content change(s) to the revised new SAT result in differential linking functions across gender groups. Results of population sensitivity analyses are reported on the…

  8. Approximate Solutions in Planted 3-SAT

    NASA Astrophysics Data System (ADS)

    Hsu, Benjamin; Laumann, Christopher; Moessner, Roderich; Sondhi, Shivaji

    2013-03-01

    In many computational settings, there exists many instances where finding a solution requires a computing time that grows exponentially in the number of variables. Concrete examples occur in combinatorial optimization problems and cryptography in computer science or glassy systems in physics. However, while exact solutions are often known to require exponential time, a related and important question is the running time required to find approximate solutions. Treating this problem as a problem in statistical physics at finite temperature, we examine the computational running time in finding approximate solutions in 3-satisfiability for randomly generated 3-SAT instances which are guaranteed to have a solution. Analytic predictions are corroborated by numerical evidence using stochastic local search algorithms. A first order transition is found in the running time of these algorithms.

  9. Space radiation incident on SATS missions

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.

    1973-01-01

    A special orbital radiation study was conducted in order to evaluate mission encountered energetic particle fluxes. This information is to be supplied to the project subsystem engineers for their guidance in designing flight hardware to withstand the expected radiation levels. Flux calculations were performed for a set of 20 nominal trajectories placed at several altitudes and inclinations. Temporal variations in the ambient electron environment were considered and partially accounted for. Magnetic field calculations were performed with a current field model, extrapolated to the tentative SATS launch epoch with linear time terms. Orbital flux integrations ware performed with the latest proton and electron environment models, using new computational methods. The results are presented in graphical and tabular form. Estimates of energetic solar proton fluxes are given for a one year mission at selected integral energies ranging from 10 to 100 Mev, calculated for a year of maximum solar activity during the next solar cycle.

  10. 3D Printing the Complete CubeSat

    NASA Technical Reports Server (NTRS)

    Kief, Craig

    2015-01-01

    The 3D Printing the Complete CubeSat project is designed to advance the state-of-the-art in 3D printing for CubeSat applications. Printing in 3D has the potential to increase reliability, reduce design iteration time and provide greater design flexibility in the areas of radiation mitigation, communications, propulsion, and wiring, among others. This project is investigating the possibility of including propulsion systems into the design of printed CubeSat components. One such concept, an embedded micro pulsed plasma thruster (mPPT), could provide auxiliary reaction control propulsion for a spacecraft as a means to desaturate momentum wheels.

  11. Optimal cooperative CubeSat maneuvers obtained through parallel computing

    NASA Astrophysics Data System (ADS)

    Ghosh, Alexander; Coverstone, Victoria

    2015-02-01

    CubeSats, the class of small standardized satellites, are quickly becoming a prevalent scientific research tool. The desire to perform ambitious missions using multiple CubeSats will lead to innovations in thruster technology and will require new tools for the development of cooperative trajectory planning. To meet this need, a new software tool was created to compute propellant-minimizing maneuvers for two or more CubeSats. By including parallelization techniques, this tool is shown to run significantly faster than its serial counterpart.

  12. Solving SAT Problem Based on Hybrid Differential Evolution Algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Kunqi; Zhang, Jingmin; Liu, Gang; Kang, Lishan

    Satisfiability (SAT) problem is an NP-complete problem. Based on the analysis about it, SAT problem is translated equally into an optimization problem on the minimum of objective function. A hybrid differential evolution algorithm is proposed to solve the Satisfiability problem. It makes full use of strong local search capacity of hill-climbing algorithm and strong global search capability of differential evolution algorithm, which makes up their disadvantages, improves the efficiency of algorithm and avoids the stagnation phenomenon. The experiment results show that the hybrid algorithm is efficient in solving SAT problem.

  13. Function analysis of a new type I PKS-SAT domain by SAT-EAT domain replacement.

    PubMed

    Jiao, Y L; Wang, L H; Jiao, B H; Wang, S J; Fang, Y W; Liu, S

    2010-01-01

    The function of a new starter unit acyltransferase (SAT) domain SAT-EF080951 (GenBank accession number) encoded in a new type I polyketide synthase (PKS) gene cluster EF568935 (GenBank accession number) isolated for this study was analyzed by domain replacement with an extender unit AT (EAT) domain of avermectin PKS. It was shown that the SAT-EF080951 incorporated malonyl-CoA specifically in vivo, which contradicted the specificity that we had previously determined by substrate binding test in vitro. The result of this study indicates that type I PKS-SAT can alter its specificity in vivo and functions well in extender units and proved the feasibility of the SAT-EAT domain replacement in type I PKS. We propose that SAT-EAT replacement strategy could be a novel route for increasing the diversity of new polyketides combinatorially biosynthesized. The new type I PKS-SAT-EF080951 studied herein may be further employed for related studies on enzymology or combinatorial biosynthesis of polyketides. PMID:20391758

  14. FalconSAT-7: a membrane space telescope

    NASA Astrophysics Data System (ADS)

    Andersen, Geoff; Asmolova, Olha; Dickinson, Thomas

    2014-06-01

    The USAF Academy Department of Physics is building FalconSAT-7, a membrane solar telescope to be deployed from a 3U CubeSat in LEO. The primary optic is a 0.2m photon sieve.—a diffractive element consisting of billions of tiny holes in an otherwise opaque polymer sheet. The membrane, its support structure, secondary optics, two imaging cameras and associated control/recording electronics are all packaged within half the CubeSat volume. Once in space the supporting pantograph structure is deployed, pulling the membrane flat under tension. The telescope will then be steered towards the Sun to gather images at H-alpha for transmission to the ground. Due for launch in 2016, FalconSAT-7 will serve as a pathfinder for future surveillance missions.

  15. Skunk Works type approach for F-SAT

    NASA Astrophysics Data System (ADS)

    Turner, Gary F.

    The topics are presented in viewgraph form and include the following: the F-SAT Program, the classic program organization, design/configuration management, procurement/material, manufacturing, quality assurance, the facility, and personnel management.

  16. Skunk Works type approach for F-SAT

    NASA Technical Reports Server (NTRS)

    Turner, Gary F.

    1992-01-01

    The topics are presented in viewgraph form and include the following: the F-SAT Program, the classic program organization, design/configuration management, procurement/material, manufacturing, quality assurance, the facility, and personnel management.

  17. Onboard autonomy on the Three Corner Sat Mission

    NASA Technical Reports Server (NTRS)

    Chien, S.; Engelhardt, B.; Knight, R.; Rabideau, G.; Sherwood, R.

    2001-01-01

    Three Corner Sat (3CS) is a mission of three university nanosatellites scheduled for launch on September 2002. The 3CS misison will utilize significan onboard autonomy to perform onboard science data validation and replanning.

  18. Atmospheric Entry Aerothermodynamics Flight Test on CubeSat Platform

    NASA Astrophysics Data System (ADS)

    Sakraker, I.; Umit, E.; van der Haegen, V.; Chazot, O.

    2014-06-01

    The challenging aerothermochemistry of atmospheric entry is aimed to be experimented on a triple CubeSat platform having ablative TPS in the front unit and ceramic TPS on the side panels. Five aerothermodynamics payloads are presented in this paper.

  19. A SAT Encoding for Multi-dimensional Packing Problems

    NASA Astrophysics Data System (ADS)

    Grandcolas, Stéphane; Pinto, Cédric

    The Orthogonal Packing Problem (OPP) consists in determining if a set of items can be packed into a given container. This decision problem is NP-complete. Fekete et al. modelled the problem in which the overlaps between the objects in each dimension are represented by interval graphs. In this paper we propose a SAT encoding of Fekete et al. characterization. Some results are presented, and the efficiency of this approach is compared with other SAT encodings.

  20. SAT Encoding and CSP Reduction for Interconnected Alldiff Constraints

    NASA Astrophysics Data System (ADS)

    Lardeux, Frederic; Monfroy, Eric; Saubion, Frederic; Crawford, Broderick; Castro, Carlos

    Constraint satisfaction problems (CSP) or Boolean satisfiability problem (SAT) are two well known paradigm to model and solve combinatorial problems. Modeling and resolution of CSP is often strengthened by global constraints (e.g., Alldiff constraint). This paper highlights two different ways of handling specific structural information: a uniform propagation framework to handle (interleaved) Alldiff constraints with some CSP reduction rules; and a SAT encoding of these rules that preserves the reduction properties of CSP.

  1. Miniature scientific-grade magnetic sensors for CubeSats

    NASA Astrophysics Data System (ADS)

    Pronenko, Vira; Belyayev, Serhiy

    2016-07-01

    Micro- and nanosatellites have become more attractive due to their low development and launch cost. A class of nanosatellites defined by the CubeSat standard allows standardizing CubeSat preparation and launch, thus making the projects more affordable. Because of the complexity of sensors miniaturization to install them onboard CubeSat, the majority of CubeSat launches are aimed the technology demonstration or education missions. The scientific success of CubeSat mission depends on the sensors quality. In spite that the sensitivity of the magnetic sensors strongly depends on their size, the recent development in this branch allows us to propose tiny but sensitive both AC and DC magnetometers. The goal of the present report is to introduce the new design of miniature three-component sensors for measurement of vector magnetic fields - for quasi-stationary and slowly fluctuating - flux-gate magnetometer (FGM) - and for alternative ones - search-coil magnetometer (SCM). In order to create magnetometers with the really highest possible level of parameters, a set of scientific and technological problems, mostly aimed at the sensor construction improvement, was solved. The most important parameter characterizing magnetometer quality is its own magnetic noise level (NL). The analysis of the NL influencing factors is made and the ways to decrease it are discussed in the report. Construction details and technical specifications of miniature but sensitive FGM and SCM for the CubeSat mission are presented. This work is supported by EC Framework 7 funded project 607197.

  2. PhoneSat In-flight Experience Results

    NASA Technical Reports Server (NTRS)

    Salas, Alberto Guillen; Attai, Watson; Oyadomari, Ken Y.; Priscal, Cedric; Schimmin, Rogan S.; Gazulla, Oriol Tintore; Wolfe, Jasper L.

    2014-01-01

    Over the last decade, consumer technology has vastly improved its performances, become more affordable and reduced its size. Modern day smartphones offer capabilities that enable us to figure out where we are, which way we are pointing, observe the world around us, and store and transmit this information to wherever we want. These capabilities are remarkably similar to those required for multi-million dollar satellites. The PhoneSat project at NASA Ames Research Center is building a series of CubeSat-size spacecrafts using an off-the-shelf smartphone as its on-board computer with the goal of showing just how simple and cheap space can be. Since the PhoneSat project started, different suborbital and orbital flight activities have proven the viability of this revolutionary approach. In early 2013, the PhoneSat project launched the first triage of PhoneSats into LEO. In the five day orbital life time, the nano-satellites flew the first functioning smartphone-based satellites (using the Nexus One and Nexus S phones), the cheapest satellite (a total parts cost below $3,500) and one of the fastest on-board processors (CPU speed of 1GHz). In this paper, an overview of the PhoneSat project as well as a summary of the in-flight experimental results is presented.

  3. Validity of the SAT for Predicting Second-Year Grades: 2006 SAT Validity Sample. Statistical Report No. 2011-1

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2011-01-01

    This report presents the validity of the SAT for predicting two second-year outcomes: (1) second-year cumulative GPA (2nd Yr Cum GPA), and (2) second-year grade point average (2nd Yr GPA). Similar to the results for first-year grade point average (1st Yr GPA), the SAT is strongly correlated with second year outcomes. For many significant…

  4. Validity of the SAT for Predicting Third-Year Grades: 2006 SAT Validity Sample. Statistical Report No. 2011-3

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2006-01-01

    This report presents the validity of the SAT for predicting two third-year college outcomes: (1) third-year cumulative GPA (3rd Yr Cum GPA), and (2) third-year grade point average (3rd Yr GPA). Similar to the results for first- and second-year outcomes (1st Yr GPA, 2nd Yr GPA, 2nd Yr Cum GPA), the SAT is strongly correlated with third year…

  5. Isoform-level brain expression profiling of the spermidine/spermine N1-Acetyltransferase1 (SAT1) gene in major depression and suicide

    PubMed Central

    Pantazatos, Spiro P.; Andrews, Stuart J.; Dunning-Broadbent, Jane; Pang, Jiuhong; Huang, Yung-yu; Arango, Victoria; Nagy, Peter L.; Mann, J. John

    2016-01-01

    Low brain expression of the spermidine/spermine N-1 acetyltransferase (SAT1) gene, the rate-limiting enzyme involved in catabolism of polyamines that mediate the polyamine stress response (PSR), has been reported in depressed suicides. However, it is unknown whether this effect is associated with depression or with suicide and whether all or only specific isoforms expressed by SAT1, such as the primary 171 amino acid protein-encoding transcript (SSAT), or an alternative splice variant (SSATX) that is involved in SAT1 regulated unproductive splicing and transcription (RUST), are involved. We applied next generation sequencing (RNA-seq) to assess gene-level, isoform-level, and exon-level SAT1 expression differences between healthy controls (HC, N = 29), DSM-IV major depressive disorder suicides (MDD-S, N = 21) and MDD non-suicides (MDD, N = 9) in the dorsal lateral prefrontal cortex (Brodmann Area 9, BA9) of medication-free individuals postmortem. Using small RNA-seq, we also examined miRNA species putatively involved in SAT1 post-transcriptional regulation. A DSM-IV diagnosis was made by structured interview. Toxicology and history ruled out recent psychotropic medication. At the gene-level, we found low SAT1 expression in both MDD-S (vs. HC, p = 0.002) and MDD (vs. HC, p = 0.002). At the isoform-level, reductions in MDD-S (vs. HC) were most pronounced in four transcripts including SSAT and SSATX, while reductions in MDD (vs. HC) were pronounced in three transcripts, one of which was reduced in MDD relative to MDD-S (all p < 0.1 FDR corrected). We did not observe evidence for differential exon-usage (i.e. splicing) nor differences in miRNA expression. Results replicate the finding of low SAT1 brain expression in depressed suicides in an independent sample and implicate low SAT1 brain expression in MDD independent of suicide. Low expressions of both SSAT and SATX isoforms suggest that shared transcriptional mechanisms involved in RUST may account for low SAT1 brain

  6. Topside Ionospheric Sounder for CubeSats

    NASA Astrophysics Data System (ADS)

    Swenson, C.; Pratt, J.; Fish, C. S.; Winkler, C.; Pilinski, M.; Azeem, I.; Crowley, G.; Jeppesen, M.; Martineau, R.

    2014-12-01

    This presentation will outline the design of a Topside Ionospheric Sounder (TIS) for CubeSats. In the same way that an ionosonde measures the ionospheric profile from the ground, a Topside Sounder measures the ionospheric profile from a location above the F-region peak. The TIS will address the need for increased space situational awareness and environmental monitoring by estimating electron density profiles in the topside of the ionosphere. The TIS will measure topside electron density profiles for plasma frequencies ranging from 0.89 MHz to 28.4 MHz below the satellite altitude. The precision of the measurement will be 5% or 10,000 p/cm^3. The TIS average power consumption will be below 10 W and a mass of less than 10 kg, so it is appropriate for a 6U Cubesat (or multiple of that size). The sounder will operate via a transmitted frequency sweep across the desired plasma frequencies which, upon reception, can be differenced to determine range and density information of the topside ionosphere. The velocity of the spacecraft necessitates careful balancing of range resolution and frequency knowledge requirements as well as novel processing techniques to correctly associate the return signal with the correct plasma frequency. TIS is being designed to provide a low cost, low mass spacecraft that can provide accurate topside profiles of the ionospheric electron density in order to further understanding of ionospheric structure and dynamic processes in the ionosphere.

  7. Memorial consequences of answering SAT II questions.

    PubMed

    Marsh, Elizabeth J; Agarwal, Pooja K; Roediger, Henry L

    2009-03-01

    Many thousands of students take standardized tests every year. In the current research, we asked whether answering standardized test questions affects students' later test performance. Prior research has shown both positive and negative effects of multiple-choice testing on later tests, with negative effects arising from students selecting incorrect alternatives on multiple-choice tests and then believing they were correct (Roediger & Marsh, 2005). In the current experiments, undergraduates and high school students answered multiple-choice questions retired from SAT II tests (that are no longer in the testing pool) on biology, chemistry, U.S. history, and world history, and later answered cued-recall questions about these subjects. In 3 experiments, we observed positive testing effects: More final cued-recall questions were answered correctly if the items had appeared on the initial multiple-choice test. We also sometimes observed negative testing effects: intrusions of multiple-choice distractors as answers on the final cued-recall test. Students who scored well on the initial test benefited from taking the test, but lower achieving students showed either less benefit (undergraduates) or costs from the testing (high school students). PMID:19309212

  8. Science-Driven NanoSats Design for Deep Space

    NASA Astrophysics Data System (ADS)

    Klesh, A. T.; Castillo, J. C.

    2012-12-01

    CubeSat-based exploration of Earth has driven the development of miniaturized systems and research-grade instruments. The current performance of CubeSats raises the question of their potential contribution to planetary exploration. Two possible applications can be foreseen. One would take advantage of the readily availability of the CubeSat deployer Poly Picosatellite Orbital Deployer (P-POD) for planetary-related observations around Earth (e.g., O/OREOS mission, ExoPlanetSat), and, when propulsion systems develop, for interplanetary exploration. However, the CubeSat formfactor restricts payloads to be in an undeployed volume of 10x10x10 (1U) to 10x20x30 (6U) cm, based on the qualified and accepted P-POD. As a possible alternative, one may leverage the CubeSat-tailored subsystems to operate that platform as a secondary payload on a deep space mission. Whether the CubeSat formfactor constraint might be adjusted to accommodate a broader range of science applications or specific tailoring is required remains to be quantified. Through consultation with a wide range of scientists and engineers, we have examined the possible applications of secondary deep space NanoSats, and what derived requirements stem from these missions. Applications and requirements, together with existing technology, inform on common formfactors that could be useful for future planetary missions. By examining these formfactors, we have identified different categories of NanoSat explorer (additionally imposing discrete requirements on the mothership) that directly support scientific endeavors. In this paper, we outline some of the scientific applications that would drive the NanoSat formfactor design, as well as describe how the requirements affect programmatic issues. Several mission types are considered: passive deployment, active propulsion, targeted landing, and sample return. Each scenario changes the risk posture, and can impose additional considerations. Our goal has been to identify

  9. Systematic review: Comparison of Xpert MTB/RIF, LAMP and SAT methods for the diagnosis of pulmonary tuberculosis.

    PubMed

    Yan, Liping; Xiao, Heping; Zhang, Qing

    2016-01-01

    Technological advances in nucleic acid amplification have led to breakthroughs in the early detection of PTB compared to traditional sputum smear tests. The sensitivity and specificity of loop-mediated isothermal amplification (LAMP), simultaneous amplification testing (SAT), and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis were evaluated. A critical review of previous studies of LAMP, SAT, and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis that used laboratory culturing as the reference method was carried out together with a meta-analysis. In 25 previous studies, the pooled sensitivity and specificity of the diagnosis of tuberculosis were 93% and 94% for LAMP, 96% and 88% for SAT, and 89% and 98% for Xpert MTB/RIF. The I(2) values for the pooled data were >80%, indicating significant heterogeneity. In the smear-positive subgroup analysis of LAMP, the sensitivity increased from 93% to 98% (I(2) = 2.6%), and specificity was 68% (I(2) = 38.4%). In the HIV-infected subgroup analysis of Xpert MTB/RIF, the pooled sensitivity and specificity were 79% (I(2) = 72.9%) and 99% (I(2) = 64.4%). In the HIV-negative subgroup analysis for Xpert MTB/RIF, the pooled sensitivity and specificity were 72% (I(2) = 49.6%) and 99% (I(2) = 64.5%). LAMP, SAT and Xpert MTB/RIF had comparably high levels of sensitivity and specificity for the diagnosis of tuberculosis. The diagnostic sensitivity and specificity of three methods were similar, with LAMP being highly sensitive for the diagnosis of smear-positive PTB. The cost effectiveness of LAMP and SAT make them particularly suitable tests for diagnosing PTB in developing countries. PMID:26786658

  10. CubeSat Material Limits for Design for Demise

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.

    2014-01-01

    The CubeSat form factor of nano-satellite (a satellite with a mass between one and ten kilograms) has grown in popularity due to their ease of construction and low development and launch costs. In particular, their use as student led payload design projects has increased due to the growing number of launch opportunities. CubeSats are often deployed as secondary or tertiary payloads on most US launch vehicles or they may be deployed from the ISS. The focus of this study will be on CubeSats launched from the ISS. From a space safety standpoint, the development and deployment processes for CubeSats differ significantly from that of most satellites. For large satellites, extensive design reviews and documentation are completed, including assessing requirements associated with re-entry survivability. Typical CubeSat missions selected for ISS deployment have a less rigorous review process that may not evaluate aspects beyond overall design feasibility. CubeSat design teams often do not have the resources to ensure their design is compliant with re-entry risk requirements. A study was conducted to examine methods to easily identify the maximum amount of a given material that can be used in the construction of a CubeSats without posing harm to persons on the ground. The results demonstrate that there is not a general equation or relationship that can be used for all materials; instead a limiting value must be defined for each unique material. In addition, the specific limits found for a number of generic materials that have been previously used as benchmarking materials for re-entry survivability analysis tool comparison will be discussed.

  11. Solar neutron observations with ChubuSat-2 satellite

    NASA Astrophysics Data System (ADS)

    Yamaoka, Kazutaka

    2016-07-01

    Solar neutron observation is a key in understanding of ion accerelation mechanism in the Sun surface since neutrons are hardly affected by magnetic field around the Sun and intersteller mediums unlike charged particles. However, there was only a few tenth detections so far since its discovery in 1982. Actually SEDA-AP Fiber detector (FIB) onboard the International Space Station (ISS) was suffered from a high neutron background produced by the ISS itself. ChubuSat is a series of 50-kg class microsatellite jointly depeloped by universities (Nagoya university and Daido university) and aerospace companies at the Chubu area of central Japan. The ChubuSat-2 is the second ChubuSat following the ChubuSat-1 which was launched by Russian DNEPR rocket on November 6, 2014. It was selected as one of four piggyback payloads of the X-ray astronomy satellite ASTRO-H in 2014 summer, and will be launched by the H-IIA launch vehcles from from JAXA Tanegashima Space Center (TNSC) in February 2016. The ChubuSat-2 carries a mission instrument, radiation detector (RD). The main mission of ChubuSat-2 is devoted for monitoring neutrons and gamma-rays which can be background source for ASTRO-H celestrial observations with the RD. The mission also involves a function of solar neutron observations which were originally proposed by graduate students who join the leadership development program for space exploration and research, program for leading graduate schools at Nagoya University. The RD has a similar detection area and efficiency to those of the SEDA-AP FIB, but is expected to have lower backgrounthan the ISS thanks to much smaller mass of the micro-satellite. In this paper, we will describe details of ChubuSat-2 satellite and RD, and in-orbit performance of RD.

  12. CubeSat Material Limits For Design for Demise

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.

    2014-01-01

    The CubeSat form factor of nano-satellite (a satellite with a mass between one and ten kilograms) has grown in popularity due to their ease of construction and low development and launch costs. In particular, their use as student led payload design projects has increased due to the growing number of launch opportunities. CubeSats are often deployed as secondary or tertiary payloads on most US launch vehicles or they may be deployed from the ISS. The focus of this study will be on CubeSats launched from the ISS. From a space safety standpoint, the development and deployment processes for CubeSats differ significantly from that of most satellites. For large satellites, extensive design reviews and documentation are completed, including assessing requirements associated with reentry survivability. Typical CubeSat missions selected for ISS deployment have a less rigorous review process that may not evaluate aspects beyond overall design feasibility. CubeSat design teams often do not have the resources to ensure their design is compliant with reentry risk requirements. A study was conducted to examine methods to easily identify the maximum amount of a given material that can be used in the construction of a CubeSats without posing harm to persons on the ground. The results demonstrate that there is not a general equation or relationship that can be used for all materials; instead a limiting value must be defined for each unique material. In addition, the specific limits found for a number of generic materials that have been previously used as benchmarking materials for reentry survivability analysis tool comparison will be discussed.

  13. CloudSat as a Global Radar Calibrator

    SciTech Connect

    Protat, Alain; Bouniol, Dominique; O'Connor, E. J.; Baltink, Henk K.; Verlinde, J.; Widener, Kevin B.

    2011-03-01

    The calibration of the CloudSat spaceborne cloud radar has been thoroughly assessed using very accurate internal link budgets before launch, comparisons with predicted ocean surface backscatter at 94 GHz, direct comparisons with airborne cloud radars, and statistical comparisons with ground-based cloud radars at different locations of the world. It is believed that the calibration of CloudSat is accurate to within 0.5 to 1 dB. In the present paper it is shown that an approach similar to that used for the statistical comparisons with ground-based radars can now be adopted the other way around to calibrate other ground-based or airborne radars against CloudSat and / or detect anomalies in long time series of ground-based radar measurements, provided that the calibration of CloudSat is followed up closely (which is the case). The power of using CloudSat as a Global Radar Calibrator is demonstrated using the Atmospheric Radiation Measurement cloud radar data taken at Barrow, Alaska, the cloud radar data from the Cabauw site, The Netherlands, and airborne Doppler cloud radar measurements taken along the CloudSat track in the Arctic by the RASTA (Radar SysTem Airborne) cloud radar installed in the French ATR-42 aircraft for the first time. It is found that the Barrow radar data in 2008 are calibrated too high by 9.8 dB, while the Cabauw radar data in 2008 are calibrated too low by 8.0 dB. The calibration of the RASTA airborne cloud radar using direct comparisons with CloudSat agrees well with the expected gains and losses due to the change in configuration which required verification of the RASTA calibration.

  14. Expanding CubeSat Capabilities with a Low Cost Transceiver

    NASA Technical Reports Server (NTRS)

    Palo, Scott; O'Connor, Darren; DeVito, Elizabeth; Kohnert, Rick; Schaire, Scott H.; Bundick, Steve; Crum, Gary; Altunc, Serhat; Winkert, Thomas

    2014-01-01

    CubeSats have developed rapidly over the past decade with the advent of a containerized deployer system and ever increasing launch opportunities. These satellites have moved from an educational tool to teach students about engineering challenges associated with satellite design, to systems that are conducting cutting edge earth, space and solar science. Early variants of the CubeSat had limited functionality and lacked sophisticated attitude control, deployable solar arrays and propulsion. This is no longer the case and as CubeSats mature, such systems are becoming commercially available. The result is a small satellite with sufficient power and pointing capabilities to support a high rate communication system. Communications systems have matured along with other CubeSat subsystems. Originally developed from amateur radio systems, CubeSats have generally operated in the VHF and UHF bands at data rates below 10 kbps (kilobits per second). More recently higher rate UHF systems have been developed, however these systems require a large collecting area on the ground to close the communications link at 3 Mbps (megabits per second). Efforts to develop systems that operate with similar throughput at S-Band (2-4 GHz (gigaherz)) and C-Band (4-8 GHz (gigaherz)) have also recently evolved. In this paper we outline an effort to develop a high rate CubeSat communication system that is compatible with the NASA Near Earth Network and can be accommodated by a CubeSat. The system will include a 200 kbps (kilobits per second) S-Band receiver and a 12.5 Mbps (megabits per second).X-Band transmitter. This paper will focus on our design approach and initial results associated with the 12.5 Mbps (megabits per second) X-band transmitter.

  15. A novel solid-angle tomosynthesis (SAT) scanning scheme

    SciTech Connect

    Zhang Jin; Yu, Cedric

    2010-08-15

    Purpose: Digital tomosynthesis (DTS) recently gained extensive research interests in both diagnostic and radiation therapy fields. Conventional DTS images are generated by scanning an x-ray source and flat-panel detector pair on opposite sides of an object, with the scanning trajectory on a one-dimensional curve. A novel tomosynthesis method named solid-angle tomosynthesis (SAT) is proposed, where the x-ray source scans on an arbitrary shaped two-dimensional surface. Methods: An iterative algorithm in the form of total variation regulated expectation maximization is developed for SAT image reconstruction. The feasibility and effectiveness of SAT is corroborated by computer simulation studies using three-dimensional (3D) numerical phantoms including a 3D Shepp-Logan phantom and a volumetric CT image set of a human breast. Results: SAT is able to cover more space in Fourier domain more uniformly than conventional DTS. Greater coverage and more isotropy in the frequency domain translate to fewer artifacts and more accurately restored features in the in-plane reconstruction. Conclusions: Comparing with conventional DTS, SAT allows cone-shaped x-ray beams to project from more solid angles, thus provides more coverage in the spatial-frequency domain, resulting in better quality of reconstructed image.

  16. Extravehicular Activity System Sizing Analysis Tool (EVAS_SAT)

    NASA Technical Reports Server (NTRS)

    Brown, Cheryl B.; Conger, Bruce C.; Miranda, Bruno M.; Bue, Grant C.; Rouen, Michael N.

    2007-01-01

    An effort was initiated by NASA/JSC in 2001 to develop an Extravehicular Activity System Sizing Analysis Tool (EVAS_SAT) for the sizing of Extravehicular Activity System (EVAS) architecture and studies. Its intent was to support space suit development efforts and to aid in conceptual designs for future human exploration missions. Its basis was the Life Support Options Performance Program (LSOPP), a spacesuit and portable life support system (PLSS) sizing program developed for NASA/JSC circa 1990. EVAS_SAT estimates the mass, power, and volume characteristics for user-defined EVAS architectures, including Suit Systems, Airlock Systems, Tools and Translation Aids, and Vehicle Support equipment. The tool has undergone annual changes and has been updated as new data have become available. Certain sizing algorithms have been developed based on industry standards, while others are based on the LSOPP sizing routines. The sizing algorithms used by EVAS_SAT are preliminary. Because EVAS_SAT was designed for use by members of the EVA community, subsystem familiarity on the part of the intended user group and in the analysis of results is assumed. The current EVAS_SAT is operated within Microsoft Excel 2003 using a Visual Basic interface system.

  17. Mathematical SAT Test Scores and College Chemistry Grades

    NASA Astrophysics Data System (ADS)

    Spencer, Harry E.

    1996-12-01

    The relationships between mathematical SAT scores (SAT-M) and grades earned by students in eight consecutive years of first- and second-semester general chemistry courses at Oberlin College are reported. The academic years surveyed are 1987-1988 through 1994-1995. SAT-M scores are grouped within seven ranges from 450 and less to 710-800. Within any range of scores, students in both courses earned a wide variety of grades, but those within the higher ranges tended to earn higher grades and fewer failures relative to students in the lower ranges. For all students within each range of SAT-M scores, the fraction earning each grade are calculated. These fractions along with the numbers of students and their SAT-M scores in a subset are used to calculate grades expected for that subset. In the first-semester course, the expected and actual grades for subsets of males, females, first-year students, non-first-year students, Asians, Blacks, and Latinos are not significantly different. Those who eventually majored in chemistry or biochemistry attained grades very significantly higher than expected. Most students tended to achieve grades in the second-semester course that were similar to those earned in the first-semester course.

  18. A novel solid-angle tomosynthesis (SAT) scanning scheme

    PubMed Central

    Zhang, Jin; Yu, Cedric

    2010-01-01

    Purpose: Digital tomosynthesis (DTS) recently gained extensive research interests in both diagnostic and radiation therapy fields. Conventional DTS images are generated by scanning an x-ray source and flat-panel detector pair on opposite sides of an object, with the scanning trajectory on a one-dimensional curve. A novel tomosynthesis method named solid-angle tomosynthesis (SAT) is proposed, where the x-ray source scans on an arbitrary shaped two-dimensional surface. Methods: An iterative algorithm in the form of total variation regulated expectation maximization is developed for SAT image reconstruction. The feasibility and effectiveness of SAT is corroborated by computer simulation studies using three-dimensional (3D) numerical phantoms including a 3D Shepp–Logan phantom and a volumetric CT image set of a human breast. Results: SAT is able to cover more space in Fourier domain more uniformly than conventional DTS. Greater coverage and more isotropy in the frequency domain translate to fewer artifacts and more accurately restored features in the in-plane reconstruction. Conclusions: Comparing with conventional DTS, SAT allows cone-shaped x-ray beams to project from more solid angles, thus provides more coverage in the spatial-frequency domain, resulting in better quality of reconstructed image. PMID:20879579

  19. Forecasting Evaluation of WindSat in the Coastal Environment

    NASA Technical Reports Server (NTRS)

    Lee, Thomas F.; Bettenhausen, Mike H.; Hawkins, Jeffrey D.; Richardson, Kim; Jedlovec, Gary; Smith, Matt

    2012-01-01

    WindSat has demonstrated that measurements from polarimetric space-based microwave radiometers can be used to retrieve global ocean surface vector winds. Since the date of launch in 2003, substantial incremental improvements have been made to WindSat data processing, calibration, and retrieval algorithms. The retrievals now have higher resolution, improved wind vector ambiguity removal, and enhanced capability to represent high winds. Utilization of WindSat retrievals (wind vectors, total precipitable water, rainrate and sea surface temperature) will be demonstrated in the context of operational weather forecasting applications, especially the monitoring of topographically-forced winds. Examples will be presented from various parts of the world, including inland seas, midlatitude oceans, the tropics, and the United States. We will illustrate retrievals in extreme high- and extreme low-wind regimes, both of which can be problematic. Rain contamination will be addressed. We will include a comparison of WindSat vector maps to corresponding maps from the QuikScat scatterometer. We will discuss how near-realtime data from WindSat is being transitioned to specific offices within the National Weather Service.

  20. Synthesis, spectroscopic and structural elucidation of 1-butyl-4-[2-(3,5-dimethoxy-4-hydroxyphenyl)ethenyl)]pyridinium chloride tetrahydrate.

    PubMed

    Koleva, B B; Kolev, T; Lamshöft, M; Mayer-Figge, H; Sheldrick, W S; Spiteller, M

    2009-12-01

    The novel chloride salt of 1-butyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridine (1), has been synthesized as the tetrahydrate and its structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and mass spectrometry. Quantum chemical calculations were performed with a view to supporting and explaining the experimental structural and spectroscopic data. The compound (1) crystallizes in triclinic P1 space group and its unit cell contains two independent 1-butyl-4-[2-(3,5-dimethoxy4-hydroxyphenyl)ethenyl)]pyridinium] cations, differing with respect to the butyl chain torsion angle for which values of 80.0(9) degrees and 173.6(3) degrees are observed. The cations and anions are joined into infinite layers, formed by two different dimers and including solvent molecules. Hydrogen bonds OH...OH(2) (2.814 A), HOH...O(CH(3)) (2.960 A), OH...Cl (2.967 A), HOH...Cl(-) (3.034, 3.188, 3.161 and 3.062 A) and HOH...OH(2) (2.772 A) are observed. For first time in the literature, we are reporting the crystal structure of the dye with the syring-fragment in the molecule. The spectroscopic properties of the novel compound are compared and with those of the corresponding quinoide form (2). Both the forms (1) and (2) are characterized by 21 and 140 nm solvatochromic effects depending of the type of the solvent. The UV-spectroscopic data in solution confirm the formation of classical H-aggregates in polar protic solvent mixture. PMID:19833548

  1. Synthesis, spectroscopic and structural elucidation of 1-butyl-4-[2-(3,5-dimethoxy-4-hydroxyphenyl)ethenyl)]pyridinium chloride tetrahydrate

    NASA Astrophysics Data System (ADS)

    Koleva, B. B.; Kolev, T.; Lamshöft, M.; Mayer-Figge, H.; Sheldrick, W. S.; Spiteller, M.

    2009-12-01

    The novel chloride salt of 1-butyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridine ( 1), has been synthesized as the tetrahydrate and its structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and mass spectrometry. Quantum chemical calculations were performed with a view to supporting and explaining the experimental structural and spectroscopic data. The compound ( 1) crystallizes in triclinic P1¯ space group and its unit cell contains two independent 1-butyl-4-[2-(3,5-dimethoxy4-hydroxyphenyl)ethenyl)]pyridinium] cations, differing with respect to the butyl chain torsion angle for which values of 80.0(9)° and 173.6(3)° are observed. The cations and anions are joined into infinite layers, formed by two different dimers and including solvent molecules. Hydrogen bonds OH⋯OH 2 (2.814 Å), HOH⋯O(CH 3) (2.960 Å), OH⋯Cl (2.967 Å), HOH⋯Cl - (3.034, 3.188, 3.161 and 3.062 Å) and HOH⋯OH 2 (2.772 Å) are observed. For first time in the literature, we are reporting the crystal structure of the dye with the syring-fragment in the molecule. The spectroscopic properties of the novel compound are compared and with those of the corresponding quinoide form ( 2). Both the forms ( 1) and ( 2) are characterized by 21 and 140 nm solvatochromic effects depending of the type of the solvent. The UV-spectroscopic data in solution confirm the formation of classical H-aggregates in polar protic solvent mixture.

  2. HaloSat: A CubeSat to Map the Distribution of Baryonic Matter in the Galactic Halo

    NASA Astrophysics Data System (ADS)

    Miles, Drew M.

    2016-04-01

    Approximately half of predicted baryonic matter in the Milky Way remains unidentified. One possible explanation for the location of this missing matter is in an extended Galactic halo. HaloSat is a CubeSat that aims to constrain the mass and distribution of the halo’s baryonic matter by obtaining an all-sky map of O VII and O VIII emission in the hot gas associated with the halo of the Milky Way. HaloSat offers an improvement in the quality of measurements of oxygen line emission over existing X-ray observatories and an observation plan dedicated to mapping the hot gas in the Galactic halo. In addition to the missing baryon problem, HaloSat will assign a portion of its observations to the solar wind charge exchange (SWCX) in order to calibrate models of SCWX emission. We present here the current status of HaloSat and the progression of instrument development in anticipation of a 2018 launch.

  3. Experimental infection of giraffe (Giraffa camelopardalis) with SAT-1 and SAT-2 foot-and-mouth disease virus.

    PubMed

    Vosloo, W; Swanepoel, S P; Bauman, M; Botha, B; Esterhuysen, J J; Boshoff, C I; Keet, D F; Dekker, A

    2011-04-01

    The potential role of giraffe (Giraffa camelopardalis) in the epidemiology and spread of foot-and-mouth disease (FMD) SAT types was investigated by experimental infection and detection of virus in excretions using virus isolation on primary pig kidney cell cultures. In two experiments separated by a period of 24 months, groups of four animals were needle infected with a SAT-1 or SAT-2 virus, respectively and two in-contact controls were kept with each group. Viraemia was detected 3-9 days post-infection and virus isolated from mouth washes and faeces only occasionally up to day 13. The SAT-1 virus was transmitted to only one in-contact control animal, probably via saliva that contained virus from vesicles in the mouth of a needle-infected animal. None of the animals infected with the SAT-2 virus had any vesicles in the mouth, and there was no evidence of transmission to the in-contact controls. No virus was detected in probang samples for the duration of the experiments (60 days post-infection), indicating that persistent infection probably did not establish with either of these isolates. Giraffe most likely do not play an important role in FMD dissemination. Transmission of infection would possibly occur only during close contact with other animals when mouth vesicles are evident. PMID:26353052

  4. Phased array antenna investigation for CubeSat size satellites

    NASA Astrophysics Data System (ADS)

    Dang, Kien

    Increasing bandwidth of the communication link has been a challenge for CubeSat class satellite. Traditional satellites usually utilizes high gain antennas for this purpose, but these antenna are rarely seen in CubeSat because of its power, volume and weight constraints. To solve these issues, this dissertation presents a phased array antenna system prototyped at 2.45 GHz with 17.7 dBi gain at broadside, 14.2 dBi at +/-40°, 50 MHz bandwidth, and fits on a side of a 3U CubeSat. The gain can be increased by adding more antenna elements into the array as needed. Testing for electronic beam steering has been completed and detailed results will be presented.

  5. Origami NanoSat Telescopes: Planetary Astronomy's Future unfolds

    NASA Astrophysics Data System (ADS)

    Marchis, F.; Castillo-Rogez, J.; Jenkins, J.; Dissly, R.; Klesh, A.

    2013-09-01

    We will present a concept to develop a key technology to expand the application of NanoSats to astronomy. The NanoSat size intrinsically constrains the aperture diameter of an onboard telescope to a few centimeters; consequently it limits the sensitivity of the instruments and the scientific return of the mission. An obvious but challenging solution is to encapsulate a deployable telescope in a NanoSat platform and deploy it in space after launch. A revolutionary advance is to add state-of-the-art wavefront sensing and control to a large deployable aperture, and then combine this with excellent pointing stability on such a small platform. We focus this study on a few significant science drivers, which appear to be the most beneficial to the planetary science science decadal survey, the astrophysics decadal survey NASA Strategic goals and plans, and will drive the design of the satellite.

  6. COLD-SAT orbital experiment configured for Atlas launch

    NASA Technical Reports Server (NTRS)

    Shuster, J. R.; Bennett, F. O.; Wachter, J. P.

    1989-01-01

    The design and requirements for the proposed cryogenic on-orbit liquid depot storage, acquisition, and transfer (COLD-SAT) satellite experiment, which is to be launched by Atlas I, are examined. The COLD-SAT experiments are categorized as class I and II; class I involves technology related to space transportation missions and class II represents alternative fluid management operations and data. The hardware for the COLD-SAT experiments consists of three hydrogen tanks contained in the experimental module; the experimental module is connected to a three-axis-controlled spacecraft bus, and thrusters are positioned on the forward and aft ends of the spacecraft and on the cylindrical portion of the experimental module. The components and systems of the experiment module and the types of experiments that can be conducted in each tank are described. Diagrams of the spacecraft configuration are provided.

  7. Solving SAT and Hamiltonian Cycle Problem Using Asynchronous P Systems

    NASA Astrophysics Data System (ADS)

    Tagawa, Hirofumi; Fujiwara, Akihiro

    In the present paper, we consider fully asynchronous parallelism in membrane computing, and propose two asynchronous P systems for the satisfiability (SAT) and Hamiltonian cycle problem. We first propose an asynchronous P system that solves SAT with n variables and m clauses, and show that the proposed P system computes SAT in O(mn2n) sequential steps or O(mn) parallel steps using O(mn) kinds of objects. We next propose an asynchronous P system that solves the Hamiltonian cycle problem with n nodes, and show that the proposed P system computes the problem in O(n!) sequential steps or O(n2) parallel steps using O(n2) kinds of objects.

  8. iSat Surface Charging and Thruster Plume Interactions Analysis

    NASA Technical Reports Server (NTRS)

    Parker, L. Neergaard; Willis, E.; Minow, J.

    2016-01-01

    NASA is designing the Iodine Satellite (iSAT) cubesat mission to demonstrate operations of an iodine electric thruster system. The spacecraft will be deployed as a secondary payload from a launch vehicle which has not yet been identified so the program must plan for the worst case environments over a range of orbital inclinations. We present results from a NASA and Air Force Charging Analyzer Program (NASCAP-2K) surface charging calculation used to evaluate the effects of charging on the spacecraft and to provide the charging levels at other locations in orbit for a thruster plume interaction analysis for the iSAT mission. We will then discuss results from the thruster interactions analysis using the Electric Propulsion Interactions Code (EPIC). The results of these analyses are being used by the iSAT program for a range of environments that could be encountered when the final mission orbit is selected.

  9. LifeSat - A satellite for space biological research

    NASA Technical Reports Server (NTRS)

    Halstead, Thora W.; Morey-Holton, Emily R.

    1990-01-01

    The LifeSat Program addresses the need for continuing access by biological scientists to space experimentation by accommodating a wide range of experiments involving animals and plants for durations up to 60 days in an unmanned satellite. The program will encourage interdisciplinary and international cooperation at both the agency and scientist levels, and will provide a recoverable, reusable facility for low-cost missions addressing key scientific issues that can only be answered by space experimentation. It will provide opportunities for research in gravitational biology and on the effects of cosmic radiation on life systems. The scientific aspects of LifeSat are addressed here.

  10. Radiation Tolerant, FPGA-Based SmallSat Computer System

    NASA Technical Reports Server (NTRS)

    LaMeres, Brock J.; Crum, Gary A.; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Radiation Tolerant, FPGA-based SmallSat Computer System (RadSat) computing platform exploits a commercial off-the-shelf (COTS) Field Programmable Gate Array (FPGA) with real-time partial reconfiguration to provide increased performance, power efficiency and radiation tolerance at a fraction of the cost of existing radiation hardened computing solutions. This technology is ideal for small spacecraft that require state-of-the-art on-board processing in harsh radiation environments but where using radiation hardened processors is cost prohibitive.

  11. Mars Moons Prospector Mission with CubeSats

    NASA Astrophysics Data System (ADS)

    Udrea, Bogdan; Nayak, Mikey; Allen, Brett; Bourke, Justin; Casariego, Gabriela; Gosselin, Steven; Hiester, Evan; Maier, Margaret; Melchert, Jeanmarie; Patel, Chitrang; Reis, Leslie; Smith, Gregory; Snow, Travis; Williams, Sarah; Franquiz, Francsico

    2015-04-01

    The preliminary design of a low-cost Discovery class mission for prospecting Mars moons Phobos and Deimos is undertaken as capstone senior design class in spacecraft design. The mission design is centred on a mothership that carries a dozen of 12U CubeSats, each of 22x22x34cm in size and 24kg in mass. The mothership is equipped with a set of instruments for the investigation of regolith samples, similar to those with identical functions on the Curiosity and the Mars 2020 rovers. The mothership also serves as a telecommunication hub with Earth. Six of the CubeSats have the role of touching down and picking up soil samples for delivery to the mothership for analysis and the six have the role of visually inspecting the moon at close proximity in visible and near and mid infrared light and deploying instruments on the surface of the moons. A suite of miniaturized instruments are investigated for deployment on the CubeSats. The CubeSats are designed to dock with the mothership to be refueled and they heavily leverage the design of the ARAPAIMA (www.eraucubesat.org) proximity operations 6U CubeSat currently in development at ERAU for the Air Force University Nanosatellite Program. The concept of operations envisions the launch of the mothership as a primary payload on a Mars transfer trajectory. After performing a Mars capture maneuver the mothership undertakes autonomous aerobraking to achieve a highly elliptic orbit with the apoapsis at Deimos altitude of 23,460km. Further maneuvering places the mothership in a relative orbit about Deimos from which the CubeSats are deployed. Once the investigation of Deimos is completed the mothership retrieves its CubeSats and maneuver to achieve a relative orbit about Phobos. An investigation similar to that of Deimos is performed. If the mass margins allow it then an extended mission will attempt to confirm the presence of a dust ring between Phobos and Deimos and conduct multi-point atmospheric investigations with supplemental 3U

  12. Integrated Solar-Panel Antenna Array for CubeSats

    NASA Technical Reports Server (NTRS)

    Baktur, Reyhan

    2016-01-01

    The goal of the Integrated Solar-Panel Antenna Array for CubeSats (ISAAC) project is to design and demonstrate an effective and efficien toptically transparent, high-gain, lightweight, conformal X-band antenna array that is integrated with the solar panels of a CubeSat. The targeted demonstration is for a Near Earth Network (NEN)radio at X-band, but the design can be easilyscaled to other network radios for higher frequencies. ISAAC is a less expensive and more flexible design for communication systemscompared to a deployed dish antenna or the existing integrated solar panel antenna design.

  13. Some results for k-SAT on trees

    NASA Astrophysics Data System (ADS)

    Sumedha; Krishnamurthy, Supriya

    2015-09-01

    Phase transitions in random k-SAT problems are connected to their computational complexity. While polynomical time algorithms are known to solve the problem for k = 2, for k ≥ 3 the problem is known to be NP-complete. Recently we have studied random k-SAT and many of its variants on regular infinite trees. We find that the solvability threshold for k = 2 matches the exact value of the threshold on regular random graphs. For higher k, the values are very close to those predicted using other techniques like cavity method.

  14. Preliminary analysis of a radiobiological experiment for LifeSat

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.; Nealy, John E.; Hardy, Alva C.; Atwell, William; Schimmerling, Walter

    1991-01-01

    With the possibility of performing radiation life science experiments on a dedicated satellite (LifeSat) in space, a combined effort in radiation physics and radiation dosimetry, in addition to radiation biology, is clearly required to ensure that meaningful biological experiments can be performed. To better understand the relationship of these disciplines, some possible LifeSat missions are examined. As a trial biological system, tumorigenesis is considered in the Harderian gland of mice, a system of sufficient radiosensitivity for which relative biological effectiveness (RBE) is well defined by laboratory experiments.

  15. A New Assay for Determining Ganglioside Sialyltransferase Activities Lactosylceramide-2,3-Sialyltransferase (SAT I) and Monosialylganglioside-2,3-Sialyltransferase (SAT IV)

    PubMed Central

    Sun, Cynthia Q.; Hubl, Ulrike; Hoefakker, Petra; Vasudevamurthy, Madhusudan K.; Johnson, Keryn D.

    2014-01-01

    A new assay for the determination of lactosylceramide-2,3-sialyltransferase (SAT I, EC 2.4.99.9) and monosialoganglioside sialyltransferase (SAT IV, EC 2.4.99.2) is described. The assay utilised the commercially available fluorophore labelled sphingolipids, boron dipyrromethene difluoride (BODIPY) lactosylceramide (LacCer), and BODIPY-monosialotetrahexosylganglioside (GM1) as the acceptor substrates, for SAT I and SAT IV, respectively. HPLC coupled with fluorescence detection was used to analyse product formation. The analysis was performed in a quick and automated fashion. The assay showed good linearity for both BODIPY sphingolipids with a quantitative detection limit of 0.05 pmol. The high sensitivity enabled the detection of SAT I and SAT IV activities as low as 0.001 μU, at least 200 fold lower than that of most radiometric assays. This new assay was applied to the screening of SAT I and SAT IV activities in ovine and bovine organs (liver, heart, kidney, and spleen). The results provided evidence that young animals, such as calves, start to produce ganglioside sialyltransferases as early as 7 days after parturition and that levels change during maturation. Among the organs tested from a bovine source, spleen had the highest specific ganglioside sialyltransferase activity. Due to the organ size, the greatest total ganglioside sialyltransferase activities (SAT I and SAT IV) were detected in the liver of both bovine and ovine origin. PMID:24718572

  16. A new assay for determining ganglioside sialyltransferase activities lactosylceramide-2,3-sialyltransferase (SAT I) and monosialylganglioside-2,3-sialyltransferase (SAT IV).

    PubMed

    Sun, Cynthia Q; Hubl, Ulrike; Hoefakker, Petra; Vasudevamurthy, Madhusudan K; Johnson, Keryn D

    2014-01-01

    A new assay for the determination of lactosylceramide-2,3-sialyltransferase (SAT I, EC 2.4.99.9) and monosialoganglioside sialyltransferase (SAT IV, EC 2.4.99.2) is described. The assay utilised the commercially available fluorophore labelled sphingolipids, boron dipyrromethene difluoride (BODIPY) lactosylceramide (LacCer), and BODIPY-monosialotetrahexosylganglioside (GM1) as the acceptor substrates, for SAT I and SAT IV, respectively. HPLC coupled with fluorescence detection was used to analyse product formation. The analysis was performed in a quick and automated fashion. The assay showed good linearity for both BODIPY sphingolipids with a quantitative detection limit of 0.05 pmol. The high sensitivity enabled the detection of SAT I and SAT IV activities as low as 0.001 μU, at least 200 fold lower than that of most radiometric assays. This new assay was applied to the screening of SAT I and SAT IV activities in ovine and bovine organs (liver, heart, kidney, and spleen). The results provided evidence that young animals, such as calves, start to produce ganglioside sialyltransferases as early as 7 days after parturition and that levels change during maturation. Among the organs tested from a bovine source, spleen had the highest specific ganglioside sialyltransferase activity. Due to the organ size, the greatest total ganglioside sialyltransferase activities (SAT I and SAT IV) were detected in the liver of both bovine and ovine origin. PMID:24718572

  17. CryoSat Plus For Oceans: an ESA Project for CryoSat-2 Data Exploitation Over Ocean

    NASA Astrophysics Data System (ADS)

    Benveniste, J.; Cotton, D.; Clarizia, M.; Roca, M.; Gommenginger, C. P.; Naeije, M. C.; Labroue, S.; Picot, N.; Fernandes, J.; Andersen, O. B.; Cancet, M.; Dinardo, S.; Lucas, B. M.

    2012-12-01

    The ESA CryoSat-2 mission is the first space mission to carry a space-borne radar altimeter that is able to operate in the conventional pulsewidth-limited (LRM) mode and in the novel Synthetic Aperture Radar (SAR) mode. Although the prime objective of the Cryosat-2 mission is dedicated to monitoring land and marine ice, the SAR mode capability of the Cryosat-2 SIRAL altimeter also presents the possibility of demonstrating significant potential benefits of SAR altimetry for ocean applications, based on expected performance enhancements which include improved range precision and finer along track spatial resolution. With this scope in mind, the "CryoSat Plus for Oceans" (CP4O) Project, dedicated to the exploitation of CryoSat-2 Data over ocean, supported by the ESA STSE (Support To Science Element) programme, brings together an expert European consortium comprising: DTU Space, isardSAT, National Oceanography Centre , Noveltis, SatOC, Starlab, TU Delft, the University of Porto and CLS (supported by CNES),. The objectives of CP4O are: - to build a sound scientific basis for new scientific and operational applications of Cryosat-2 data over the open ocean, polar ocean, coastal seas and for sea-floor mapping. - to generate and evaluate new methods and products that will enable the full exploitation of the capabilities of the Cryosat-2 SIRAL altimeter , and extend their application beyond the initial mission objectives. - to ensure that the scientific return of the Cryosat-2 mission is maximised. In particular four themes will be addressed: -Open Ocean Altimetry: Combining GOCE Geoid Model with CryoSat Oceanographic LRM Products for the retrieval of CryoSat MSS/MDT model over open ocean surfaces and for analysis of mesoscale and large scale prominent open ocean features. Under this priority the project will also foster the exploitation of the finer resolution and higher SNR of novel CryoSat SAR Data to detect short spatial scale open ocean features. -High Resolution Polar

  18. Validity Comparison of PCAT and SAT in the Prediction of First-Year GPA

    ERIC Educational Resources Information Center

    Kotzan, Jeffrey A.; Entrekin, Durward N.

    1977-01-01

    University of Georgia pharmacy students were studied to determine whether (1) SAT factor scores related to a measure of pharmacy student performance as well as PCAT factor scores, and (2) a combination of PCAT factors, SAT factors, and other available applicant information improved the validity of the singular use of SAT or PCAT. (LBH)

  19. The Shrinking Black-White Gap on SAT II Achievement Tests.

    ERIC Educational Resources Information Center

    Journal of Blacks in Higher Education, 2002

    2002-01-01

    Recent research shows that the SAT II test is a much better predictor of college success than the standard SAT. In recent years, black students appear to be making progress in closing the racial scoring gap on the wide variety of academic subjects (particularly chemistry, world history, and biology) that are measured by the SAT II test. (SM)

  20. The Rise and Demise of the SAT: The University of California Generates Change for College Admissions

    ERIC Educational Resources Information Center

    Berger, Susan J.

    2012-01-01

    Over the past few months, news about the Scholastic Assessment Test (SAT) has made national headlines and not in a good way: "Large SAT Score Decline Shows Failure of No Child Left Behind and State High-Stakes Testing Strategy" (FairTest 2011); "Eshaghoff, Emory University Student, Allegedly Took SAT For Other Students" (Huffington Post 2011); and…

  1. The Effect of Personality Preferences on the 2005 Version of the SAT

    ERIC Educational Resources Information Center

    Burrs, Ashley

    2013-01-01

    Some researchers suggest the Scholastic Aptitude Test (SAT) is biased toward certain personality types. Extant literature lacked examination of personality constructs and their relationship with SAT scores of the newly revised SAT. The purpose of this study was two-fold. First, this study examined the relationship between the Sensing and Intuition…

  2. An Alternative Presentation of Incremental Validity: Discrepant SAT and HSGPA Performance

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Shaw, Emily J.; Kobrin, Jennifer L.

    2011-01-01

    This study examined discrepant high school grade point average (HSGPA) and SAT performance as measured by the difference between a student's standardized SAT composite score and standardized HSGPA. The SAT-HSGPA discrepancy measure was used to examine whether certain students are more likely to exhibit discrepant performance and in what direction.…

  3. A CubeSat for Calibrating Ground-Based and Sub-Orbital Millimeter-Wave Polarimeters (CalSat)

    NASA Astrophysics Data System (ADS)

    Johnson, Bradley R.; Vourch, Clement J.; Drysdale, Timothy D.; Kalman, Andrew; Fujikawa, Steve; Keating, Brian; Kaufman, Jon

    2015-10-01

    We describe a low-cost, open-access, CubeSat-based calibration instrument that is designed to support ground-based and sub-orbital experiments searching for various polarization signals in the cosmic microwave background (CMB). All modern CMB polarization experiments require a robust calibration program that will allow the effects of instrument-induced signals to be mitigated during data analysis. A bright, compact and linearly polarized astrophysical source with polarization properties known to adequate precision does not exist. Therefore, we designed a space-based millimeter-wave calibration instrument, called CalSat, to serve as an open-access calibrator, and this paper describes the results of our design study. The calibration source on board CalSat is composed of five “tones” with one each at 47.1, 80.0, 140, 249 and 309GHz. The five tones we chose are well matched to (i) the observation windows in the atmospheric transmittance spectra, (ii) the spectral bands commonly used in polarimeters by the CMB community and (iii) the Amateur Satellite Service bands in the Table of Frequency Allocations used by the Federal Communications Commission. CalSat would be placed in a polar orbit allowing visibility from observatories in the Northern Hemisphere, such as Mauna Kea in Hawaii and Summit Station in Greenland, and the Southern Hemisphere, such as the Atacama Desert in Chile and the South Pole. CalSat also would be observable by balloon-borne instruments launched from a range of locations around the world. This global visibility makes CalSat the only source that can be observed by all terrestrial and sub-orbital observatories, thereby providing a universal standard that permits comparison between experiments using appreciably different measurement approaches.

  4. Malaria Early Warning: The MalarSat project

    NASA Astrophysics Data System (ADS)

    Roca, M.; Escorihuela, M. J.; Martínez, D.; Torrent, M.; Aponte, J.; Nunez, F.; Garcia, J.

    2009-04-01

    Malaria is one of the major public health challenges undermining development in the world. The aim of MalarSat Project is to provide a malaria risks infection maps at global scale using Earth Observation data to support and prevent epidemic episodes. The proposed service for creating malaria risk maps would be critically useful to improve the efficiency in insecticide programs, vaccine campaigns and the logistics epidemic treatment. Different teams have already carried out studies in order to exploit the use of Earth Observation (EO) data with epidemiology purposes. In the case of malaria risk maps, it has been shown that meteorological data is not sufficient to fulfill this objective. In particular being able to map the malaria mosquito habitat would increase the accuracy of risk maps. The malaria mosquitoes mainly reproduce in new water puddles of very reduced dimensions (about 1 meter wide). There is no instrument that could detect such small patches of water unless there are many of them spread in an area of several hundreds of meters. MalarSat aims at using the radar altimeter data from the EnviSat, RA-2, to try and build indicators of mosquitoes existence. This presentation will show the scientific objectives and principles of the MalarSat project.

  5. Project ELaNa and NASA's CubeSat Initiative

    NASA Technical Reports Server (NTRS)

    Skrobot, Garrett Lee

    2010-01-01

    This slide presentation reviews the NASA program to use expendable lift vehicles (ELVs) to launch nanosatellites for the purpose of enhancing educational research. The Education Launch of Nanosatellite (ELaNa) project, run out of the Launch Services Program is requesting proposals for CubeSat type payload to provide information that will aid or verify NASA Projects designs while providing higher educational research

  6. Smart Sat experiment for the L5 mission

    NASA Astrophysics Data System (ADS)

    Akioka, M.; Ohtaka, K.; Nagatsuma, T.; Miyake, W.; Goka, T.; Matsumoto, H.; Koshiishi, H.

    We have proposed the L5 mission for space weather research and operational forecasting experiment. The spacecraft will be deployed at the L5 Point of the Sun - Earth system for remote sensing of the Sun and the interplanetary space and for in situ measurement of the solar wind plasma and high energy solar particle event. For the L5 mission, CRL and JAXA develop wide field imager for CME tracking and advanced high energy particle sensor. We plan orbital demonstration in near earth orbit before the L5 mission as the Smart Sat program. The Smart Sat is a pair of small satellites about 150Kg, which will be a collaborative program of government agency (CRL,JAXA) and private sector (MHI) in Japan. The space weather experiment of the Smart Sat consists of Wide field imager for CME tracking (WCI) and Space Environment Data Acquisition equipment (SEDA). Both of the instruments will be principal components of the L5 mission. In this article, we report an overview of the space weather experiment of Smart Sat program.

  7. Analysis of WindSat Data over Arctic Sea Ice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The radiation of the 3rd and 4th Stokes components emitted by Arctic sea ice and observed by the spaceborne fully polarimetric radiometer WindSat is investigated. Two types of analysis are carried out, spatial (maps of different quadrants of azimuth look angles) and temporal (time series of daily av...

  8. WindSat Global Soil Moisture Retrieval and Validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A physically based six-channel land algorithm is developed to simultaneously retrieve the global soil moisture, vegetation water content and land surface temperature. The algorithm is based on a maximum-likelihood estimation and uses WindSat passive microwave data at 10, 18.7 and 37 GHz. The global ...

  9. WindSat Passive Microwave Soil Moisture Retrievals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Abstract: WindSat is a spaceborne fully polarimetric conical scanning microwave radiometer. It operates at frequencies and polarizations that match other radiometers such as the Advanced Microwave Scanning Radiometer (AMSR-E) and in addition it acquires additional polarimetric measurements...

  10. Student Change, Program Change: Why SAT Scores Kept Falling.

    ERIC Educational Resources Information Center

    Turnbull, William W.

    This paper analyzes Scholastic Aptitude Test (SAT) score declines of two decades--the 1960s and 1970s. The importance of pervasive societal influences is accepted. A variety of data suggests, however, that the increase in school retention rates of poorly prepared students and the resulting heterogeneity of the high school population is a unifying…

  11. Patterns of SAT Scores, Choice of STEM Major, and Gender

    ERIC Educational Resources Information Center

    Davison, Mark L.; Jew, Gilbert B.; Davenport, Ernest C., Jr.

    2014-01-01

    Using Baccalaureate and Beyond 2001 data, we found that STEM major was associated with an SAT pattern less common among females than males, in which the student's quantitative score exceeded the verbal score. Verbal ability was negatively associated with STEM major. Implications for career theory and test interpretation are discussed.

  12. CloudSat Reflectivity Data Visualization Inside Hurricanes

    NASA Technical Reports Server (NTRS)

    Suzuki, Shigeru; Wright, John R.; Falcon, Pedro C.

    2011-01-01

    We have presented methods to rapidly produce visualization and outreach products from CloudSat data for science and the media These methods combine data from several sources in the product generation process In general, the process can be completely automatic, producing products and notifying potential users

  13. S.A.T. Drop: Let's Ban the Bomb Theory.

    ERIC Educational Resources Information Center

    American School Board Journal, 1983

    1983-01-01

    Questions radiological physicist Ernest J. Sternglass's theory that links falling Scholastic Aptitude Test (SAT) scores in the 1960s and '70s to nuclear weapons testing in the late '40s, the '50s, and early '60s. Notes other scientists' contention that Sternglass's theory only establishes a correlation, not a cause and effect relationship. (JBM)

  14. Interpreting Force Concept Inventory Scores: Normalized Gain and SAT Scores

    ERIC Educational Resources Information Center

    Coletta, Vincent P.; Phillips, Jeffrey A.; Steinert, Jeffrey J.

    2007-01-01

    Preinstruction SAT scores and normalized gains (G) on the force concept inventory (FCI) were examined for individual students in interactive engagement (IE) courses in introductory mechanics at one high school (N=335) and one university (N=292), and strong, positive correlations were found for both populations (r=0.57 and r=0.46, respectively).…

  15. The COLD-SAT experiment for cryogenic fluid management technology

    NASA Technical Reports Server (NTRS)

    Schuster, J. R.; Wachter, J. P.; Vento, D. M.

    1990-01-01

    The COLD-SAT spacecraft design experiments are described. COLD-SAT will be placed into an initial 1300 km circular orbit by an Atlas commercial launch vehicle. Electric power, experiment control and data management, attitude control, and propulsive accelarations for the experiments will be provided by the three-axis-controlled spacecraft bus. To provide data on the effects that low gravity levels might have on the heat and mass transfer processes involved, low levels of accelaration will be created. The COLD-SAT experiment will be configured into a module. The spacecraft experiment module will include three liquid hydrogen tanks; fluid transfer, pressurization and venting equipment; and instrumentation. Since the largest tank has helium-purged MLI to prevent ingress and freezing of air on the launchpad, it will contain all the liquid hydrogen at the point of launching. The hydrogen tanking system used for the Centaur upper stage of the Atlas will load and top off this tank. Atlas, with its liquid hydrogen upper stage, large payload fairing, and large launch margin, simplifies COLD-SAT design and integration.

  16. A Better SAT Starts with a Better College Board

    ERIC Educational Resources Information Center

    Katzman, John

    2014-01-01

    It is so easy to criticize the SAT that most observers overlook the weaknesses of its architect, the College Board. This author contents that, until the latter is replaced, however, the former will never be fixed. The College Board has every incentive to create a complex, stressful, expensive college admissions system. Because it is accountable to…

  17. Improving Plan Quality in SAT-Based Planning

    NASA Astrophysics Data System (ADS)

    Giunchiglia, Enrico; Maratea, Marco

    Planning as Satisfiability (SAT) is the best approach for optimally (wrt makespan) solving classical planning problems. SAT-based planners, like SATPLAN, can thus return plans having minimal makespan guaranteed. However, the returned plan does not take into account plan quality issues introduced in the last two International Planning Competitions (IPCs): such issues include minimal-actions plans and plans with "soft" goals, where a metric has to be optimized over actions/goals. Recently, an approach to address such issues has been presented, in the framework of planning as satisfiability with preferences: by modifying the heuristic of the underlying SAT solver, the related system (called SATPLAN(P)) is guaranteed to return plans with minimal number of actions, or with maximal number of soft goals satisfied. But, besides such feature, it is well-known that introducing ordering in SAT heuristics can lead to significant degradation in performances. In this paper, we present a generate-and-test approach to tackle the problem of dealing with such optimization issues: without imposing any ordering, a (candidate optimal) plan is first generated, and then a constraint is added imposing that the new plan (if any) has to be "better" than the last computed, i.e., the plan quality is increased at each iteration. We implemented this idea in SATPLAN, and compared the resulting systems wrt SATPLAN(P) and SGPlan on planning problems coming from IPCs. The analysis shows performance benefits for the new approach, in particular on planning problems with many preferences.

  18. Behind the SAT-Optional Movement: Context and Controversy

    ERIC Educational Resources Information Center

    Epstein, Jonathan P.

    2009-01-01

    The advent of the modern form of the Scholastic Aptitude Test (SAT), brought to bear by the combination of the Educational Testing Service (ETS) and Harvard's former president James Bryant Conant (Lemann 1999), was designed to promote the recognition of talent and intellect, wherever they may be found. Their aim was to provide greater educational…

  19. FalconSAT-7: a membrane space telescope

    NASA Astrophysics Data System (ADS)

    Andersen, Geoff P.; Asmolova, Olha

    2014-08-01

    The USAF Academy Department of Physics has built FalconSAT-7, a membrane solar telescope to be deployed from a 3U CubeSat in LEO. The primary optic is a 0.2m photon sieve - a diffractive element consisting of billions of tiny circular dimples etched into a Kapton sheet. The membrane, its support structure, secondary optics, two imaging cameras and associated control/recording electronics are all packaged within half the CubeSat volume. Once in space, the supporting pantograph structure is deployed, extending out and pulling the membrane flat under tension. The telescope will then be directed at the Sun to gather images at H-alpha for transmission to the ground. Due for launch in 2015, FalconSAT-7 will serve as a pathfinder for future surveillance missions consisting of a 0.3m aperture deployed from a 12U satellite. Such a telescope would be capable of providing sub-meter resolution of ground-based objects.

  20. Two Professors Retake the SAT: Is It a Good Test?

    ERIC Educational Resources Information Center

    Harper, Christopher; Vanderbei, Robert J.

    2009-01-01

    In this article, two professors retake the college-entrance exam and arrive at very different conclusions about its performance. Even though Christopher Harper has worked as a college professor for 15 years, he decided last winter to take the SAT and ACT examinations that his students needed to enter the institution where he teaches, Temple…

  1. WindSat Soil Moisture Algorithm and Validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A WindSat land algorithm that retrieves global soil moisture and vegetation water content simultaneously using the physically-based multi-channel maximum-likelihood estimation was developed and evaluated. The retrievals agree well with soil moisture climatology, and in-situ data collected from a ser...

  2. X-Band CubeSat Communication System Demonstration

    NASA Technical Reports Server (NTRS)

    Altunc, Serhat; Kegege, Obadiah; Bundick, Steve; Shaw, Harry; Schaire, Scott; Bussey, George; Crum, Gary; Burke, Jacob C.; Palo, Scott; O'Conor, Darren

    2015-01-01

    Today's CubeSats mostly operate their communications at UHF- and S-band frequencies. UHF band is presently crowded, thus downlink communications are at lower data rates due to bandwidth limitations and are unreliable due to interference. This research presents an end-to-end robust, innovative, compact, efficient and low cost S-band uplink and X-band downlink CubeSat communication system demonstration between a balloon and a Near Earth Network (NEN) ground system. Since communication systems serve as umbilical cords for space missions, demonstration of this X-band communication system is critical for successfully supporting current and future CubeSat communication needs. This research has three main objectives. The first objective is to design, simulate, and test a CubeSat S- and X-band communication system. Satellite Tool Kit (STK) dynamic link budget calculations and HFSS Simulations and modeling results have been used to trade the merit of various designs for small satellite applications. S- and X-band antennas have been tested in the compact antenna test range at Goddard Space Flight Center (GSFC) to gather radiation pattern data. The second objective is simulate and test a CubeSat compatible X-band communication system at 12.5Mbps including S-band antennas, X-band antennas, Laboratory for Atmospheric and Space Physics (LASP) /GSFC transmitter and an S-band receiver from TRL-5 to TRL-8 by the end of this effort. Different X-band communication system components (antennas, diplexers, etc.) from GSFC, other NASA centers, universities, and private companies have been investigated and traded, and a complete component list for the communication system baseline has been developed by performing analytical and numerical analysis. This objective also includes running simulations and performing trades between different X-band antenna systems to optimize communication system performance. The final objective is to perform an end-to-end X-band CubeSat communication system

  3. Proton transport in triflic acid hydrates studied via path integral car-parrinello molecular dynamics.

    PubMed

    Hayes, Robin L; Paddison, Stephen J; Tuckerman, Mark E

    2009-12-31

    The mono-, di-, and tetrahydrates of trifluoromethanesulfonic acid, which contain characteristic H(3)O(+), H(5)O(2)(+), and H(9)O(4)(+) structures, provide model systems for understanding proton transport in materials with high perfluorosulfonic acid density such as perfluorosulfonic acid membranes commonly employed in hydrogen fuel cells. Ab initio molecular dynamics simulations indicate that protons in these solids are predisposed to transfer to the water most strongly bound to sulfonate groups via a Grotthuss-type mechanism, but quickly return to the most solvated defect structure either due to the lack of a nearby species to stabilize the new defect or a preference for the proton to be maximally hydrated. Path integral molecular dynamics of the mono- and dihydrate reveal significant quantum effects that facilitate proton transfer to the "presolvated" water or SO(3)(-) in the first solvation shell and increase the Zundel character of all the defects. These trends are quantified in free energy profiles for each bonding environment. Hydrogen bonding criteria for HOH-OH(2) and HOH-O(3)S are extracted from the two-dimensional potential of mean force. The quantum radial distribution function, radius of gyration, and root-mean-square displacement position correlation function show that the protonic charge is distributed over two or more water molecules. Metastable structural defects with one excess proton shared between two sulfonate groups and another Zundel or Eigen type cation defect are found for the mono- and dihydrate but not for the tetrahydrate crystal. Results for the tetrahydrate native crystal exhibit minor differences at 210 and 250 K. IR spectra are calculated for all native and stable defect structures. Graph theory techniques are used to characterize the chain lengths and ring sizes in the hydrogen bond network. Low conductivities when limited water is present may be attributable to trapping of protons between SO(3)(-) groups and the increased

  4. Shields-1, A SmallSat Radiation Shielding Technology Demonstration

    NASA Technical Reports Server (NTRS)

    Thomsen, D. Laurence, III; Kim, Wousik; Cutler, James W.

    2015-01-01

    The NASA Langley Research Center Shields CubeSat initiative is to develop a configurable platform that would allow lower cost access to Space for materials durability experiments, and to foster a pathway for both emerging and commercial-off-the-shelf (COTS) radiation shielding technologies to gain spaceflight heritage in a relevant environment. The Shields-1 will be Langleys' first CubeSat platform to carry out this mission. Radiation shielding tests on Shields-1 are planned for the expected severe radiation environment in a geotransfer orbit (GTO), where advertised commercial rideshare opportunities and CubeSat missions exist, such as Exploration Mission 1 (EM-1). To meet this objective, atomic number (Z) graded radiation shields (Zshields) have been developed. The Z-shield properties have been estimated, using the Space Environment Information System (SPENVIS) radiation shielding computational modeling, to have 30% increased shielding effectiveness of electrons, at half the thickness of a corresponding single layer of aluminum. The Shields-1 research payload will be made with the Z-graded radiation shields of varying thicknesses to create dose-depth curves to be compared with baseline materials. Additionally, Shields-1 demonstrates an engineered Z-grade radiation shielding vault protecting the systems' electronic boards. The radiation shielding materials' performances will be characterized using total ionizing dose sensors. Completion of these experiments is expected to raise the technology readiness levels (TRLs) of the tested atomic number (Z) graded materials. The most significant contribution of the Z-shields for the SmallSat community will be that it enables cost effective shielding for small satellite systems, with significant volume constraints, while increasing the operational lifetime of ionizing radiation sensitive components. These results are anticipated to increase the development of CubeSat hardware design for increased mission lifetimes, and enable

  5. Spacecraft Charging Analysis of a CubeSat

    NASA Technical Reports Server (NTRS)

    Willis, Emily M.; Minow, Joseph I.; Parker, Linda Neergaard

    2014-01-01

    Spacecraft charging occurs when charged particles from the surrounding space plasma environment contact a spacecraft and unequal charging currents result in a net charge density accumulation on or in spacecraft materials. Charging becomes a threat when differential potentials between two points on the spacecraft or between the spacecraft and the ambient space environment build to the level that electric fields associated with the potentials exceed the electric breakdown strength of the spacecraft materials and electrostatic discharge arcs are generated. Electrostatic discharges resulting from spacecraft charging can adversely affect telemetry and cause irreparable damage to electronics. Other spacecraft charging effects include damage of solar arrays and thermal protection, enhancement of contamination of surfaces, and degradation of optics. Typically, the large government and commercial space programs include spacecraft charging analysis as part of the design process. CubeSat projects, however, usually do not have the time or funding to include a spacecraft charging analysis due to their low budget and quick-turnaround requirements. CubeSat projects also tend to rely heavily on commercial "off-the-shelf" products, many of which are not qualified for use in space, and are particularly vulnerable to the effects of the space environment. As the demand for longer and more complex CubeSat missions increases, it is becoming more and more important to consider the effects of spacecraft charging in the design process. Results of surface charging analysis using Nascap-2k on a typical CubeSat design for a polar orbit scenario are illustrated. These results show that for a polar orbiting CubeSat, spacecraft charging could be an issue and steps should be taken to mitigate the effects for these small satellites.

  6. CloudSat Education Network: Partnerships for Outreach

    NASA Astrophysics Data System (ADS)

    TeBockhorst, D.

    2014-12-01

    CloudSat Education Network (CEN): Partnerships to improve the understanding of clouds in formal and informal settings. Since The CloudSat satellite launched in 2006 the Formal and Informal education programs for the mission have been focused on bringing an understanding about the mission science and the importance of clouds, climate & weather science. This has been done by creating and strengthening partnership and collaboration within scientific and educational communities around the country and the world. Because CloudSat was formally recognized as a Earth System Science Pathfinder campaign with the GLOBE program, the CEN developed a set of field protocols for student observations that augmented the GLOBE atmosphere protocols when there was a satellite overpass. This shared process between GLOBE & CloudSat resulted in the training & creation of CEN schools that are both GLOBE schools and CloudSat schools, and also produced three GLOBE partnerships that specialize in cloud science education and outreach. In addition, the CEN has developed productive relationships with other NASA missions and EPO teams. Specifically, in collaboration with the NASA CERES mission projects S'Cool and MyNASAData, we have co-presented at NSTA conferences and with schools participating in a NASA EPOESS-funded formal education project. This collaborative work has been a very real benefit to a wide variety of audiences needing to strengthen their understanding of clouds and their roles in the earth system, and we hope will serve as a model to future missions looking to involve the public in mission science.

  7. CloudSat Anomaly Recovery and Operational Lessons Learned

    NASA Technical Reports Server (NTRS)

    Witkowski, Mona; Vane, Deborah; Livermore, Thomas; Rokey, Mark; Barthuli, Marda; Gravseth, Ian J.; Pieper, Brian; Rodzinak, Aaron; Silva, Steve; Woznick, Paul; Nayak, Michael

    2012-01-01

    In April 2011, NASA's pioneering cloud profiling radar satellite, CloudSat, experienced a battery anomaly that placed it into emergency mode and rendered it operations incapable. All initial attempts to recover the spacecraft failed as the resultant power limitations could not support even the lowest power mode. Originally part of a six-satellite constellation known as the "A-Train", CloudSat was unable to stay within its assigned control box, posing a threat to other A-Train satellites. CloudSat needed to exit the constellation, but with the tenuous power profile, conducting maneuvers was very risky. The team was able to execute a complex sequence of operations which recovered control, conducted an orbit lower maneuver, and returned the satellite to safe mode, within one 65 minute sunlit period. During the course of the anomaly recovery, the team developed several bold, innovative operational strategies. Details of the investigation into the root-cause and the multiple approaches to revive CloudSat are examined. Satellite communication and commanding during the anomaly are presented. A radical new system of "Daylight Only Operations" (DO-OP) was developed, which cycles the payload and subsystem components off in tune with earth eclipse entry and exit in order to maintain positive power and thermal profiles. The scientific methodology and operational results behind the graduated testing and ramp-up to DO-OP are analyzed. In November 2011, the CloudSat team successfully restored the vehicle to consistent operational collection of cloud radar data during sunlit portions of the orbit. Lessons learned throughout the six-month return-to-operations recovery effort are discussed and offered for application to other R&D satellites, in the context of on-orbit anomaly resolution efforts.

  8. Interpreting force concept inventory scores: Normalized gain and SAT scores

    NASA Astrophysics Data System (ADS)

    Coletta, Vincent P.; Phillips, Jeffrey A.; Steinert, Jeffrey J.

    2007-06-01

    Preinstruction SAT scores and normalized gains (G) on the force concept inventory (FCI) were examined for individual students in interactive engagement (IE) courses in introductory mechanics at one high school (N=335) and one university (N=292) , and strong, positive correlations were found for both populations ( r=0.57 and r=0.46 , respectively). These correlations are likely due to the importance of cognitive skills and abstract reasoning in learning physics. The larger correlation coefficient for the high school population may be a result of the much shorter time interval between taking the SAT and studying mechanics, because the SAT may provide a more current measure of abilities when high school students begin the study of mechanics than it does for college students, who begin mechanics years after the test is taken. In prior research a strong correlation between FCI G and scores on Lawson’s Classroom Test of Scientific Reasoning for students from the same two schools was observed. Our results suggest that, when interpreting class average normalized FCI gains and comparing different classes, it is important to take into account the variation of students’ cognitive skills, as measured either by the SAT or by Lawson’s test. While Lawson’s test is not commonly given to students in most introductory mechanics courses, SAT scores provide a readily available alternative means of taking account of students’ reasoning abilities. Knowing the students’ cognitive level before instruction also allows one to alter instruction or to use an intervention designed to improve students’ cognitive level.

  9. Scholastic Assessment Test (SAT) Results, 1997-98. Measuring Up: E&R Report No. 99.11.

    ERIC Educational Resources Information Center

    Fejoku, Caroline Gay

    The Scholastic Assessment Tests (SAT) are national examinations designed to assess a student's chances of success at the college level. There are two SAT examinations, the SAT I, a reasoning assessment of students' verbal and mathematics skills, and the SAT II, in which students are tested in specific subject areas. In Wake County (North…

  10. California and the SAT: A Reanalysis of University of California Admissions Data. Research & Occasional Paper Series: CSHE.8.04

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Brown, Terran; Sklar, Jeffrey C.

    2004-01-01

    As part of the University of California's recent reconsideration of the role of the SAT in admissions, the UC Office of the President published an extensive report, "UC and the SAT" (2001), which examined the value of SAT I Reasoning Test scores, SAT II Subject Test scores, and high school grades in predicting the grade-point averages of UC…

  11. The Revised SAT Score and Its Potential Benefits for the Admission of Minority Students to Higher Education

    ERIC Educational Resources Information Center

    Santelices, Maria Veronica; Wilson, Mark

    2015-01-01

    This paper investigates the predictive validity of the Revised SAT (R-SAT) score, proposed by Freedle (2003) as an alternative to compensate minority students for the potential harm caused by the relationship between item difficulty and ethnic DIF observed in the SAT. The R-SAT score is the score minority students would have received if only the…

  12. SAT predicts GPA better for high ability subjects: Implications for Spearman's Law of Diminishing Returns.

    PubMed

    Coyle, Thomas; Snyder, Anissa; Pillow, David; Kochunov, Peter

    2011-04-01

    This research examined the predictive validity of the SAT (formerly, the Scholastic Aptitude Test) for high and low ability groups. SAT scores and college GPAs were obtained from the 1997 National Longitudinal Survey of Youth. Subjects were classified as high or low ability by g factor scores from the Armed Services Vocational Aptitude Battery. SAT correlations with GPA were higher for high than low ability subjects. SAT g loadings (i.e., SAT correlations with g) were equivalent for both groups. This is the first study to show that the predictive validity of the SAT varies for ability groups that differ in g. The results contradict a presumption, based on Spearman's Law of Diminishing Returns, that a test's predictive validity should be lower for high ability subjects. Further research is needed to identify factors that contribute to the predictive validity of the SAT for groups that differ in g. PMID:21562615

  13. Secreted autotransporter toxin (Sat) triggers autophagy in epithelial cells that relies on cell detachment.

    PubMed

    Liévin-Le Moal, Vanessa; Comenge, Yannick; Ruby, Vincent; Amsellem, Raymonde; Nicolas, Valérie; Servin, Alain L

    2011-07-01

    The secreted autotransporter toxin, Sat, which belongs to the subfamily of serine protease autotransporters of Enterobacteriaceae, acts as a virulence factor in extraintestinal and intestinal pathogenic strains of Escherichia coli. We observed that HeLa cells exposed to the cell-free culture supernatant of recombinant strain AAEC185p(Sat-IH11128) producing the Sat toxin (CFCS(Sat) ), displayed dramatic disorganization of the F-actin cytoskeleton before loosening cell-to-cell junctions and detachment. Examination of the effect of Sat on GFP-microtubule-associated protein light chain 3 (LC3) HeLa cells revealed that CFCS(Sat) -induced autophagy follows CFCS(Sat) -induced F-actin cytoskeleton rearrangement. The induced autophagy shows an acceleration of the autophagy flux soon after Sat treatment, followed later by a blockade of the flux leading to the accumulation of large GFP-LC3-positive vacuoles in the cell cytoplasm. CFCS(Sat) did not induce cell detachment in autophagy-deficient mouse embryonic fibroblasts in contrast with wild-type mouse embryonic fibroblasts. The CFCS(Sat) -induced large GFP-LC3 dots do not display the characteristics of autophagolysosomes including expression of cathepsin D and Lamp-1 and 2 proteins, and Lysotracker Red- and DQ-BSA-positive labelling. We provide evidences that CFCS(Sat) -induced autophagy is not a cell response intended to get rid of the intracellular toxin. By a pharmacological blockers approach, we found that the blockade of Erk1/2 and p38 MAPKs, but not JNK, inhibited the CFCS(Sat) -induced autophagy and cell detachment whereas phosphatidylinositol-3 kinase blockers inhibiting canonical autophagy were inactive. When attached CFCS(Sat) -treated cells start to detach they showed caspase-independent cell death and rearrangements of the focal adhesion-associated vinculin and paxillin. Collectively, our results support that Sat triggers autophagy in epithelial cells that relies on its cell-detachment effect. PMID:21501364

  14. Improved Oceanographic Measurements with CryoSat SAR Altimetry

    NASA Astrophysics Data System (ADS)

    Cotton, David; Benveniste, Jérôme; Cipollini, Paolo; Andersen, Ole; Cancet, Mathilde; Ambrózio, Américo; Restano, Marco; Nilo Garcia, Pablo; Martin, Francisco

    2016-07-01

    The ESA CryoSat mission is the first space mission to carry a radar altimeter that can operate in Synthetic Aperture Radar "SAR" (or delay-Doppler) and interferometric SAR (SARin) modes. Studies on CryoSat data have analysed and confirmed the improved ocean measuring capability offered by SAR mode altimetry, through increased resolution and precision in sea surface height and wave height measurements, and have also added significantly to our understanding of the issues around the processing and interpretation of SAR altimeter echoes. We present work in four themes, building on work initiated in the CryoSat Plus for Oceans project (CP4O), each investigating different aspects of the opportunities offered by this new technology. The first two studies address the coastal zone, a critical region for providing a link between open-ocean and shelf sea measurements with those from coastal in-situ measurements, in particular tide gauges. Although much has been achieved in recent years through the Coastal Altimetry community, (http://www.coastalt.eu/community) there is a limit to the capabilities of pulse-limited altimetry, which often leaves an un-measured "white strip" right at the coastline. Firstly, a thorough analysis was made of the performance of "SAR" altimeter data (delay-Doppler processed) in the coastal zone. This quantified the performance, confirming the significant improvement over "conventional" pulse-limited altimetry. In the second study a processing scheme was developed with CryoSat SARin mode data to enable the retrieval of valid oceanographic measurements in coastal areas with complex topography. Thanks to further development of the algorithms, a new approach was achieved that can also be applied to SAR and conventional altimetry data (e.g., Sentinel-3, Jason series, Envisat). The third part of the project developed and evaluated improvements to the SAMOSA altimeter re-tracker that is implemented in the Sentinel-3 processing chain. The modifications to the

  15. Uncooled emissive infrared imagers for CubeSats

    NASA Astrophysics Data System (ADS)

    Puschell, Jeffery J.; Masini, Paolo

    2014-09-01

    Raytheon's fourth generation uncooled microbolometer array technology with digital output, High Definition (HD) 1920 × 1200 format and 12 μm cell size enables uncooled thermal infrared (TIR) multispectral imagers with the sensitivity and spatial sampling needed for a variety of Earth observation missions in LEO, GEO and HEO. A powerful combination of small detector cell size, fast optics and high sensitivity achieved without cryogenic cooling leads to instruments that are much smaller than current TIR systems, while still offering the capability to meet challenging measurement requirements for Earth observation missions. To consider how this technology could be implemented for Earth observation missions, we extend our previous studies with visible wavelength CubeSat imagers for environmental observations from LEO and examine whether small thermal infrared imagers based on fourth generation uncooled technology could be made small enough to fit onboard a 3U CubeSat and still meet challenging requirements for legacy missions. We found that moderate spatial resolution (~200 m) high sensitivity cloud and surface temperature observations meeting legacy MODIS/VIIRS requirements could be collected successfully with CubeSat-sized imagers but that multiple imagers are needed to cover the full swath for these missions. Higher spatial resolution land imagers are more challenging to fit into the CubeSat form factor, but it may be possible to do so for systems that require roughly 100 m spatial resolution. Regardless of whether it can fit into a CubeSat or not, uncooled land imagers meeting candidate TIR requirements can be implemented with a much smaller instrument than previous imagers. Even though this technology appears to be very promising, more work is needed to qualify this newly available uncooled infrared technology for use in space. If these new devices prove to be as space worthy as the first generation arrays that Raytheon qualified and built into the THEMIS imager

  16. Science Case for Planetary Exploration with Planetary CubeSats and SmallSats

    NASA Astrophysics Data System (ADS)

    Castillo-Rogez, Julie; Raymond, Carol; Jaumann, Ralf; Vane, Gregg; Baker, John

    2016-07-01

    Nano-spacecraft and especially CubeSats are emerging as viable low cost platforms for planetary exploration. Increasing miniaturization of instruments and processing performance enable smart and small packages capable of performing full investigations. While these platforms are limited in terms of payload and lifetime, their form factor and agility enable novel mission architectures and a refreshed relationship to risk. Leveraging a ride with a mothership to access far away destinations can significantly augment the mission science return at relatively low cost. Depending on resources, the mothership may carry several platforms and act as telecom relay for a distributed network or other forms of fractionated architectures. In Summer 2014 an international group of scientists, engineers, and technologists started a study to define investigations to be carried out by nano-spacecrafts. These applications flow down from key science priorities of interest across space agencies: understanding the origin and organization of the Solar system; characterization of planetary processes; assessment of the astrobiological significance of planetary bodies across the Solar system; and retirement of strategic knowledge gaps (SKGs) for Human exploration. This presentation will highlight applications that make the most of the novel architectures introduced by nano-spacecraft. Examples include the low cost reconnaissance of NEOs for science, planetary defense, resource assessment, and SKGs; in situ chemistry measurements (e.g., airless bodies and planetary atmospheres), geophysical network (e.g., magnetic field measurements), coordinated physical and chemical characterization of multiple icy satellites in a giant planet system; and scouting, i.e., risk assessment and site reconnaissance to prepare for close proximity observations of a mothership (e.g., prior to sampling). Acknowledgements: This study is sponsored by the International Academy of Astronautics (IAA). Part of this work is

  17. The Relationship between SAT Scores and Retention to the Second Year: Replication with 2009 SAT Validity Sample. Statistical Report 2011-3

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2012-01-01

    The College Board formed a research consortium with four-year colleges and universities to build a national higher education database with the primary goal of validating the revised SAT for use in college admission. A study by Mattern and Patterson (2009) examined the relationship between SAT scores and retention to the second year of college. The…

  18. The Relationship between SAT Scores and Retention to the Second Year: 2007 SAT Validity Sample. Statistical Report No. 2011-4

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2011-01-01

    This report presents the findings from a replication of the analyses from the report, "Is Performance on the SAT Related to College Retention?" (Mattern & Patterson, 2009). The tables presented herein are based on the 2007 sample and the findings are largely the same as those presented in the original report, and show SAT scores are…

  19. SAT Performance: Understanding the Contributions of Cognitive/Learning and Social/Personality Factors

    PubMed Central

    HANNON, BRENDA; MCNAUGHTON-CASSILL, MARY

    2011-01-01

    SUMMARY This study identifies a number of sources of individual differences in SAT performance by examining the simultaneous contributions of factors from two otherwise disparate research areas, namely cognition/learning and social/personality. Preliminary analysis revealed that just the cognitive/learning measures accounted for 37.8, 41.4 and 21.9% of the variance in SAT, V-SAT and Q-SAT performance, respectively while just the social/personality measures accounted for 21.4, 18.2 and 17.3% of the variance. When combined, cognitive/learning and social/personality factors accounted for even larger amounts of variance in performance; specifically 43.4, 44.6 and 28% for the SAT, V-SAT and Q-SAT, respectively. Finally, the results revealed that three measures consistently predicted performance on the SAT, V-SAT and Q-SAT; two measures were the learning/cognitive factors of working memory and integration of new text-based information with information from long-term memory and one measure was the social/personality factor, test anxiety. PMID:21804694

  20. SAT Performance: Understanding the Contributions of Cognitive/Learning and Social/Personality Factors.

    PubMed

    Hannon, Brenda; McNaughton-Cassill, Mary

    2011-07-01

    This study identifies a number of sources of individual differences in SAT performance by examining the simultaneous contributions of factors from two otherwise disparate research areas, namely cognition/learning and social/personality. Preliminary analysis revealed that just the cognitive/learning measures accounted for 37.8, 41.4 and 21.9% of the variance in SAT, V-SAT and Q-SAT performance, respectively while just the social/personality measures accounted for 21.4, 18.2 and 17.3% of the variance. When combined, cognitive/learning and social/personality factors accounted for even larger amounts of variance in performance; specifically 43.4, 44.6 and 28% for the SAT, V-SAT and Q-SAT, respectively. Finally, the results revealed that three measures consistently predicted performance on the SAT, V-SAT and Q-SAT; two measures were the learning/cognitive factors of working memory and integration of new text-based information with information from long-term memory and one measure was the social/personality factor, test anxiety. PMID:21804694

  1. CarbonSat: ESA's Earth Explorer 8 Candidate Mission

    NASA Astrophysics Data System (ADS)

    Meijer, Y. J.; Ingmann, P.; Löscher, A.

    2012-04-01

    The CarbonSat candidate mission is part of ESA's Earth Explorer Programme. In 2010, two candidate opportunity missions had been selected for feasibility and preliminary definition studies. The missions, called FLEX and CarbonSat, are now in competition to become ESA's eighth Earth Explorer, both addressing key climate and environmental change issues. In this presentation we will provide a mission overview of CarbonSat with a focus on science. CarbonSat's primary mission objective is the quantification and monitoring of CO2 and CH4 sources and sinks from the local to the regional scale for i) a better understanding of the processes that control carbon cycle dynamics and ii) an independent estimate of local greenhouse gas emissions (fossil fuel, geological CO2 and CH4, etc.) in the context of international treaties. A second priority objective is the monitoring/derivation of CO2 and CH4 fluxes on regional to global scale. These objectives will be achieved by a unique combination of frequent, high spatial resolution (2 x 2 km2) observations of XCO2 and XCH4 coupled to inverse modelling schemes. The required random error of a single measurement at ground-pixel resolution is of the order of between 1 and 3 ppm for XCO2 and between 9 and 17 ppb for XCH4. High spatial resolution is essential in order to maximize the probability for clear-sky observations and to identify flux hot spots. Ideally, CarbonSat shall have a wide swath allowing a 6-day global repeat cycle. The CarbonSat observations will enable CO2 emissions from coal-fired power plants, localized industrial complexes, cities, and other large emitters to be objectively assessed at a global scale. Similarly, the monitoring of natural gas pipelines and compressor station leakage will become feasible. The detection and quantification of the substantial geological greenhouse gas emission sources such as seeps, volcanoes and mud volcanoes will be achieved for the first time. CarbonSat's Greenhouse Gas instrument will

  2. CloudSat Reflectivity Data Visualization Inside Hurricanes

    NASA Technical Reports Server (NTRS)

    Suzuki, Shigeru; Wright, John R.; Falcon, Pedro C.

    2011-01-01

    Animations and other outreach products have been created and released to the public quickly after the CloudSat spacecraft flew over hurricanes. The automated script scans through the CloudSat quicklook data to find significant atmospheric moisture content. Once such a region is found, data from multiple sources is combined to produce the data products and the animations. KMZ products are quickly generated from the quicklook data for viewing in Google Earth and other tools. Animations are also generated to show the atmospheric moisture data in context with the storm cloud imagery. Global images from GOES satellites are shown to give context. The visualization provides better understanding of the interior of the hurricane storm clouds, which is difficult to observe directly. The automated process creates the finished animation in the High Definition (HD) video format for quick release to the media and public.

  3. CloudSat Image of Tropical Thunderstorms Over Africa

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1

    CloudSat image of a horizontal cross-section of tropical clouds and thunderstorms over east Africa. The red colors are indicative of highly reflective particles such as water (rain) or ice crystals, which the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudS at Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The brown line below the image indicates the relative elevation of the land surface. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) visible image taken at nearly the same time.

  4. CubeSats to Explore Volatiles in Comets

    NASA Astrophysics Data System (ADS)

    Hewagama, T.; Aslam, S.; Châteauneuf, F.; Clark, P.; Folta, D.; Feaga, L.; Gorius, N.; Hurford, T.; Keidar, M.; Livengood, T.; Malphrus, B.; Mumma, M.; Nixon, C.; Villanueva, G.

    2015-10-01

    Close approach comets (<0.4 AU to Earth) are accessible to CubeSat and NanoSat missions that can return unique data not obtainable from ground-based telescopes. Primitive bodies such as comets are key to understanding Solar System formation. A low-risk, versatile, multispectral camera with integrated filters in a 6U spacecraft bus is capable of high spatial resolution mapping of the four primary volatile species CO2, H2O, CO, and organics. Simultaneous mmapping of these bands and two thermal channels will enable studying the dynamical activity of the nucleus. Assuming deployment from a launch platform above the Earth's gravity well, we find intercept trajectories using current propulsion systems.

  5. Rotary Percussive Sample Acquisition Tool (SAT): Hardware Development and Testing

    NASA Technical Reports Server (NTRS)

    Klein, Kerry; Badescu, Mircea; Haddad, Nicolas; Shiraishi, Lori; Walkemeyer, Phillip

    2012-01-01

    In support of a potential Mars Sample Return (MSR) mission an Integrated Mars Sample Acquisition and Handling (IMSAH) architecture has been proposed to provide a means for Rover-based end-to-end sample capture and caching. A key enabling feature of the architecture is the use of a low mass sample Acquisition Tool (SAT) that is capable of drilling and capturing rock cores directly within a sample tube in order to maintain sample integrity and prevent contamination across the sample chain. As such, this paper will describe the development and testing of a low mass rotary percussive SAT that has been shown to provide a means for core generation, fracture, and capture.

  6. Max 2-SAT with up to 108 qubits

    NASA Astrophysics Data System (ADS)

    Santra, Siddhartha; Quiroz, Gregory; Ver Steeg, Greg; Lidar, Daniel A.

    2014-04-01

    We experimentally study the performance of a programmable quantum annealing processor, the D-Wave One (DW1) with up to 108 qubits, on maximum SAT problem with 2 variables per clause (MAX 2-SAT) problems. We consider ensembles of random problems characterized by a fixed clause density, an external parameter which we tune through its critical value in our experiments. We demonstrate that the DW1 is sensitive to the critical value of the clause density. The DW1 results are verified and compared with akmaxsat, an exact, state-of-the-art algorithm. We study the relative performance of the two solvers and how they correlate in terms of problem hardness. We find that the DW1 performance scales more favorably with problem size and that problem hardness correlation is essentially non-existent. We discuss the relevance and limitations of such a comparison.

  7. UoSAT: A decade of experience pioneering microsatellites

    NASA Astrophysics Data System (ADS)

    Radbone, J. M.; Sweeting, M. N.

    1993-01-01

    Two satellites constructed as examples of low cost missions are examined and the technical and management techniques employed are described. Following first UoSAT missions, KITSAT-A is an experimental mission, S80/T a demonstration mission to evaluate the use of VHF frequencies for future low Earth orbit systems and CERISE, a modified microsatellite platform, will carry a classified payload. All these satellites are based on UoSAT-5 platform. Key technical and management issues for successful microsatellite missions are reviewed: simple interfaces, flexible design, control of requirements and modularity, quality and product assurance for the technical aspect, contract conditions, project length, efficient communications, integrated and co-located team, flexibility of organization and personnel for the management conditions.

  8. Soft X-Ray Polarimetry with a CubeSat

    NASA Astrophysics Data System (ADS)

    Kaaret, Philip

    2016-07-01

    We describe an instrument capable of measuring the polarization of astrophysical sources in soft X-rays that can be accomplished at modest cost by exploiting CubeSats as novel vehicles for high energy astrophysics. The instrument would re-use technologies that will be demonstrated on the HaloSat cubesat that is currently under construction. Potential target include thermally-emitting isolated neutron stars and blazars. Measurement of the polarization of X-rays emitted from the surface of a highly magnetized neutron star provides a means to test a unique signature of strong-field quantum electrodynamics and probe the neutron star magnetic field and X-ray emission geometry. Polarization measurements of blazars should strongly constrain jet emission models.

  9. Microparticle impact detector experiment on MightySat I

    NASA Astrophysics Data System (ADS)

    Serna, Patrick J.; Liechty, Gary H.; Neslen, Craig L.; del Frate, Renzo; Draper, Edwin

    1997-10-01

    The purpose of this report is to present the engineering design of a spaceborne micro particle impact detector (MPID) experiment. This experiment is manifested on a Phillips Laboratory spacecraft called MightySat I scheduled for launch in July 1998. A follow-on report will present the resulting particle impact data. The objective of this experiment is to measure direction and time of impact of spaceborne micron size particles with time of impact resolution of 0.1 seconds. The primary element in this experiment consists of two metal- oxide-semiconductor (MOS) discharge capacitor detectors that discharge upon hypervelocity particle impact. The detectors were developed by Prof. J. J. Wortman from North Carolina State University. Each MOS particle detector is 3 in by 1-1/2 in and approximately 0.013 in thick. Each particle detector is bonded to a detector assembly that is in turn mechanically fastened to the external bottom plate of the MightySat I spacecraft. The detector assembly and associated electronics weigh less than 0.4 lb and have a total impact detection area of 3.7 in(superscript 2). Each particle impact causes an impact event record to be stored in the spacecraft control unit for later downlink. Each impact event record will store time of impact and output from two coarse sun sensors. Data from the coarse sun sensors is used to help determine attitude of the spacecraft. The Phillips Laboratory MightySat I spacecraft, developed largely by CTA Space Systems in McLean, Virginia, designed for ejection from the Space Shuttle is a 6-sided composite structure, 20.5 in (height) by 19.0 in (diameter), 150 lb., and spin stabilized with 5 degree attitude knowledge. The MightySat I spacecraft is scheduled for orbit injection using a standard hitchhiker ejection system from space shuttle flight STS-88. (Ref. 1)

  10. Onboard autonomy on the Three Corner Sat mission

    NASA Technical Reports Server (NTRS)

    Chien, S. A.; Sherwood, R.

    2002-01-01

    In 2003, the student-built three satellite constellation Three Corner Sat (3CS) Mission will demonstrate onboard autonomy including: science data validation and prioritization, mission re-planning, and robust execution. Future observations will be planned onboard based on the quality of aquired science, available memory and power, and anticipated downlinks. These capabilities will allow 3CS to aquire additional science data if resources are available and to return only the highest quality science data.

  11. Maker of SAT Aims New Test at 8th Graders

    ERIC Educational Resources Information Center

    Cech, Scott J.

    2008-01-01

    Officials at the New York City-based College Board last week rolled out their newest product: ReadiStep. No, it is not a new piece of exercise equipment or a whipped dessert topping--it is a test for 8th graders that some critics are calling a pre-PSAT, referring to the Preliminary SAT assessment taken by 9th and 10th graders and owned by the…

  12. A quantum differentiation of k-SAT instances

    NASA Astrophysics Data System (ADS)

    Tamir, B.; Ortiz, G.

    2010-07-01

    We present a quantum adiabatic algorithm to differentiate between k-SAT instances, those with no solutions and those that have many solutions. The time complexity of the algorithm is a function of the energy gap between the subspace of all 0-eigenvectors (ground states) and the first excited states manifold, and scales polynomially with the number of resources. The idea of gaps between subspaces suggests a new tool to analyze time complexity in adiabatic quantum machines.

  13. Quantum algorithm for SAT problem andquantum mutual entropy

    NASA Astrophysics Data System (ADS)

    Ohya, Masanori

    2005-02-01

    It is von Neumann who opened the window for today's information epoch. He definedquantum entropy including Shannon's information more than 20 years ahead of Shannon, and he explained what computation means mathematically. In this paper I discuss two problems studied recently by me and my coworkers. One of them concerns a quantum algorithm in a generalized sense solving the SAT problem (one of NP complete problems) and another concerns quantum mutual entropy properly describing quantum communication processes.

  14. Dellingr- A Path to Compelling Science with CubeSats

    NASA Astrophysics Data System (ADS)

    Johnson, M.; Bonalsky, T.; Chornay, D.; Clagett, C.; Cudmore, A.; Ericsson, A.; Hesh, S.; Jones, S.; Kepko, L.; Rodriguez, J.; Sittler, E.; Starin, S.; Santos, L.; Sheikh, S.; Uribe, P.; Zesta, E.

    2015-10-01

    Advancements in the capabilities of miniaturized systems are dramatically increasing interest in achieving science from CubeSats. The Dellingr project targets this interest. It will realize compelling science from a 6U spacecraft while developing human and spacecraft systems required to cost-efficiently deliver small satellites capable of reliably achieving mission objectives in divers environments—from low earth orbit to challenging radiation and thermal environments associated with lunar and planetary missions.

  15. The e-st@r CubeSat: Antennas system

    NASA Astrophysics Data System (ADS)

    Fanchini, G.; Gagliostro, D.

    2011-12-01

    In this paper the design of a deployable antenna system for CubeSats is proposed. Its manufacturing and test for the use on e-st@r CubeSat (developed at Politecnico di Torino by students' team of the Aerospace Engineering Courses) is then reported. The design procedure is based on analyzing the CubeSat standard and defining the physical and geometrical constraints, both for a general Cubesat and the particular case of e-st@r, multiple possible configurations are analyzed and compared to define the most suitable one. The use of Components Off-The-Shelf (COTS) materials is considered for the manufacturing of all parts of the system and utilized if acceptable. The lock system can be seen as one of the critical points of the system because it has to ensure that the antenna will not open during launch, but also that it opens when in orbit, so an optimization of already existing lock systems is pursued. We considered a two fault tolerant system to have an acceptable level of confidence. Briefly the manufacturing of all parts and the tests campaign of the assembled system is then proposed with some conclusive considerations on the environmental impact of the system.

  16. LAICE CubeSat mission for gravity wave studies

    NASA Astrophysics Data System (ADS)

    Westerhoff, John; Earle, Gregory; Bishop, Rebecca; Swenson, Gary R.; Vadas, Sharon; Clemmons, James; Davidson, Ryan; Fanelli, Lucy; Fish, Chad; Garg, Vidur; Ghosh, Alex; Jagannatha, Bindu B.; Kroeker, Erik; Marquis, Peter; Martin, Daniel; Noel, Stephen; Orr, Cameron; Robertson, Robert

    2015-10-01

    The Lower Atmosphere/Ionosphere Coupling Experiment (LAICE) CubeSat mission will focus on understanding the interaction of atmospheric gravity waves generated by weather systems in the lower atmosphere with the mesosphere, lower thermosphere, and ionosphere (MLTI). Specifically, LAICE will focus on the energy and momentum delivered by these waves and attempt to connect the wave sources and the wave effects in three widely different altitude ranges, substantially adding to our knowledge of critical coupling processes between disparate atmospheric regions. The LAICE mission consists of a 6U CubeSat with a four-instrument payload. The retarding potential analyzer (RPA) will provide in-situ ion density and temperature measurements. A four-channel photometer will measure density and temperature variations in the mesosphere through observations of O2 (0, 0) Atmospheric band and O2 Herzberg I band airglows. There are two pressure sensors that comprise the Space Pressure Suite (SPS): the Space Neutral Pressure Instrument (SNeuPI) and the LAICE Ionization gauge Neutral Atmosphere Sensor (LINAS). Both will provide neutral density measurements, but SNeuPI is a prototype sensor that will be validated by LINAS. This CubeSat mission, scheduled for launch in early 2016 from the International Space Station, provides a cost-effective approach to measuring low altitude in-situ parameters along with simultaneous imaging that is capable of addressing the fundamental questions of atmospheric gravity wave coupling in the MLTI region.

  17. MitoSatPlant: mitochondrial microsatellites database of viridiplantae.

    PubMed

    Kumar, Manjeet; Kapil, Aditi; Shanker, Asheesh

    2014-11-01

    Microsatellites also known as simple sequence repeats (SSRs) consist of 1-6 nucleotide long repeating units. The importance of mitochondrial SSRs (mtSSRs) in fields like population genetics, plant phylogenetics and genome mapping motivated us to develop MitoSatPlant, a repository of plant mtSSRs. It contains information for perfect, imperfect and compound SSRs mined from 92 mitochondrial genomes of green plants, available at NCBI (as of 1 Feb 2014). A total of 72,798 SSRs were found, of which PCR primers were designed for 72,495 SSRs. Among all sequences, tetranucleotide repeats (26,802) were found to be most abundant whereas hexanucleotide repeats (2751) were detected with least frequency. MitoSatPlant was developed using SQL server 2008 and can be accessed through a front end designed in ASP.Net. It is an easy to use, user-friendly database and will prove to be a useful resource for plant scientists. To the best of our knowledge MitoSatPlant is the only database available for plant mtSSRs and can be freely accessed at http://compubio.in/mitosatplant/. PMID:24561221

  18. iSat Surface Charging and Thruster Plume Interactions Analysis

    NASA Technical Reports Server (NTRS)

    Parker, L. Neergaard; Willis, E. M.; Minow, J. I.

    2016-01-01

    Characterizing the electromagnetic interaction of a satellite in low Earth, high inclination orbit with the space plasma environment and identifying viable charging mitigation strategies is a critical mission design task. High inclination orbits expose the vehicle to auroral charging environments that can potentially charge surfaces to kilovolt potentials and electric thruster propulsion systems will interact with the ambient plasma environment throughout the orbit. NASA is designing the Iodine Satellite (iSAT) cubesat mission to demonstrate operations of an iodine electric thruster system. The spacecraft will be deployed as a secondary payload from a launch vehicle which has not yet been identified so the program must plan for the worst case environments over a range of orbital inclinations. We will first present results from a NASA and Air Force Charging Analyzer Program (Nascap) -2k surface charging calculation used to evaluate the effects of auroral charging on the spacecraft and to provide the charging levels at other locations in orbit for a thruster plume interaction analysis for the iSAT mission. We will then discuss results from the thruster interactions analysis using the Electric Propulsion Interactions Code (EPIC) with inputs from Nascap-2k. The results of these analyses are being used by the iSAT program to better understand how their spacecraft will interact with the space plasma environment in the range of environments that could be encountered when the final mission orbit is selected.

  19. The natural satellites ephemerides facility MULTI-SAT

    NASA Astrophysics Data System (ADS)

    Emel'Yanov, N. V.; Arlot, J.-E.

    2008-08-01

    Context: There is a need in some research facilities for deriving ephemerides, controlling observations, verifying various models of motion, and calculating the coordinates in space of natural planetary satellites. Aims: The goal of our work is to elaborate the ephemerides of all natural satellites based upon all observations available to date and readily accessible for any user via the Internet. Methods: For all outer planetary satellites, original numerical models of motion are used that are based on all published observations. For other satellites, the theoretical models of the motion are taken from publications that are as recent as possible. Complete collection of the theories and models of motion is realized as a software for the ephemerides of natural satellites available on the web pages of the so-called server MULTI-SAT. Results: A new facility for producing ephemerides of all natural satellites of planets (except the Moon) has been created at IMCCE and SAI. Special features of the ephemerides are realized, such as predicting the phenomena and providing configurations useful for the observers. The server MULTI-SAT is accessible through the Internet. The URL addresses are http://www.imcce.fr/sat (English and French versions at IMCCE) and http://www.sai.msu.ru/neb/nss/index.htm (English, French, and Russian versions at SAI). This paper includes a complete review of the most precise theories of motion of all natural satellites that we used and an analysis of the precision of the proposed ephemerides.

  20. Generation of Minimum-Consistent DFA Using SAT Solver

    NASA Astrophysics Data System (ADS)

    Inui, Nobuo; Aizawa, Akiko

    The purpose of this study is to develop efficient methods for the minimum-consistent DFA (deterministic finite state automaton) problem. The graph-coloring based SAT (satisfiability) approach proposed by Heule is a state of the art method for this problem. It specially achieves high performance computing in dense problems such as in a popular benchmark problem where rich information about labels is included. In contrast, to solve sparse problems is a challenge for the minimum-consistent DFA problem. To solve sparse problems, we propose three approaches to the SAT formulation: a) the binary color representation, b) the dynamic symmetry breaking and c) the hyper-graph coloring constraint. We organized an experiment using the existing benchmark problems and sparse problems made from them. We observed that our symmetry breaking constraints made the speed up the running time of SAT solver. In addition with this, our other proposed methods were showing the possibility to improve the performance. Then we simulated the perfomance of our methods under the condition that we executed the several program set-ups in parallel. Compared with the previous research results, we finally could reduce the average relative time by 66.5% and the total relative time by 7.6% for sparse problems and by 79.7% and 38.5% for dense problems, respectively. These results showed that our proposed methods were effective for difficult problems.

  1. The FedSat Experience: An Australian Research Satellite Mission

    NASA Astrophysics Data System (ADS)

    Fraser, B. J.

    In December 2002 FedSat, Australia's first satellite mission in thirty years, was launched from the Tanegashima Space Centre on the H11A-F4 rocket as a secondary payload. FedSat carries a complement of four scientific and engineering payloads in a near-circular sun synchronous 10:30 LT polar orbit at an altitude 800 km and an inclination of 98.7. Scientific experiments include a triaxial fluxgate magnetometer with a frequency response up to 100 Hz and a GPS receiver to monitor total electron content (TEC) and provide a precise orbit determination. A star camera provides precise attitude information. Communications experiments include a Ka-band transponder and a UHF packet data service. A high performance computer payload is testing reconfigurable computing technology. This paper will outline the design and development of FedSat commencing in 1998, and the unique funding situation under which the satellite and some of the payloads were successfully fabricated tested and launched.

  2. Changes of microbial substrate metabolic patterns through a wastewater reuse process, including WWTP and SAT concerning depth.

    PubMed

    Takabe, Yugo; Kameda, Ippei; Suzuki, Ryosuke; Nishimura, Fumitake; Itoh, Sadahiko

    2014-09-01

    In this study, changes of microbial substrate metabolic patterns by BIOLOG assay were discussed through a sequential wastewater reuse process, which includes activated sludge and treated effluent in wastewater treatment plant and soil aquifer treatment (SAT), especially focussing on the surface sand layer in conjunction with the vadose zone, concerning sand depth. A SAT pilot-scale reactor, in which the height of packed sand was 237 cm (vadose zone: 17 cm and saturated zone 220 cm), was operated and fed continuously by discharged anaerobic-anoxic-oxic (A2O) treated water. Continuous water quality measurements over a period of 10 months indicated that the treatment performance of the reactor, such as 83.2% dissolved organic carbon removal, appeared to be stable. Core sampling was conducted for the surface sand to a 30 cm depth, and the sample was divided into six 5 cm sections. Microbial activities, as evaluated by fluorescein diacetate, sharply decreased with increasing distance from the surface of the 30 cm core sample, which included significant decreases only 5 cm from the top surface. A similar microbial metabolic pattern containing a high degree of carbohydrates was obtained among the activated sludge, A2O treated water (influent to the SAT reactor) and the 0-5 cm layer of sand. Meanwhile, the 10-30 cm sand core layers showed dramatically different metabolic patterns containing a high degree of carboxylic acid and esters, and it is possible that the metabolic pattern exhibited by the 5-10 cm layer is at a midpoint of the changing pattern. This suggests that the removal of different organic compounds by biodegradation would be expected to occur in the activated sludge and in the SAT sand layers immediately below 5 cm from the top surface. It is possible that changes in the composition of the organic matter and/or transit of the limiting factor for microbial activities from carbon to phosphorus might have contributed to the observed dramatic changes

  3. Arctic and Antarctic Sea-Ice Freeboard and Thickness Retrievals from CryoSat-2 and EnviSat

    NASA Astrophysics Data System (ADS)

    Ricker, Robert; Hendricks, Stefan; Schwegmann, Sandra; Helm, Veit; Rinne, Eero

    2016-04-01

    The CryoSat-2 satellite is now in the 6th year of data acquisition. With its synthetic aperture radar altimeter, CryoSat-2 achieves great improvements in the along track resolution compared to previous radar altimeter missions like ERS or Envisat. The latitudinal coverage contains major parts of the Arctic marine ice fields where previous missions left a big data gap around the North Pole and especially over the multiyear ice zone north of Greenland. With this unique data set, changes in sea-ice thickness can be investigated in the context of the rapid reduction of the Arctic sea-ice cover which has been observed during the last decades. We present the current state of the CryoSat-2 Arctic sea-ice thickness retrieval that is processed at the Alfred Wegener Institute and available via seaiceportal.de (originally: meereisportal.de). Though biases in sea-ice thickness may occur due to the interpretation of waveforms, airborne and ground-based validation measurements give confidence that the retrieval algorithm enables us to capture the actual distributions of sea-ice regimes. Nevertheless, long time series of data retrievals are essential to estimate trends in sea-ice thickness and volume. Today, more than 20 years of radar altimeter data are potentially available and capable to derive sea ice thickness. However, data originate from satellites with different sensor characteristics. Therefore, it is crucial to study the consistency between single sensors to derive long and consistent time series. We present results from the tested consistency between Antarctic freeboard measurements of the radar altimeters on-board of Envisat and CryoSat-2 for their overlap period in 2011.

  4. Achieving Science Goals with CubeSats: a Study by the National Academies

    NASA Astrophysics Data System (ADS)

    Zurbuchen, T.; Sheffer, A.

    2015-12-01

    We will discuss an ongoing study by the National Academies' Space Studies Board focused on CubeSats, and in particular their scientific potential and technological promise. Through this study, several US agencies seek inputs on the current status of CubeSat programs in government, academic and industrial sectors. The study will also make recommendations about additional investments that are needed to further increase the value of CubeSats to the science community. Furthermore, the committee will provide sample priority science goals that describe near-term opportunities, such as providing continuity of key measurements to mitigate potential gaps in measurements of key parameters- and that can be accomplished given the current state of CubeSat capabilities. We will summarize some data in the public domain about CubeSats our study is based on, and also focus on some selected science opportunities that can be addressed by CubeSats and which are part of Decadal Survey priorities.

  5. Florida Tech CubeSat Experiment Feasibility Study

    NASA Technical Reports Server (NTRS)

    Arrasmith, William W.; Bucaille, Stephane; Rusovici, Razvan; Platt, Don; Guidry, Todd; Bandar, Deepika; Coots, Everett; Davidson, Russ

    2010-01-01

    CubeSats are a relatively new type of satellite. Smaller than long-term (5+ year life expectancy) satellites, these pico-satellites are comparatively cheap, small (10x10x10 cm), and are very versatile. Universities world-wide are using CubeSats to conduct a variety of experiments in space without the need for a large experimental platform. Today CubeSats are considered to be one of the most effective ways to send a small payload into space and has attracted the attention of many educational and non-profit organizations. As this pico-satellite model continues to gain penetration into the satellite build and launch industry, it is expected that more governmental, educational, and commercial interests will emerge. As an example, more of the space-related items of high interest to the National Science Foundation may be tackled with a CubeSat platform resulting in lower life cycle costs than traditional satellite options. NASA LSP, in cooperation with the Florida Institute of Technology, has initiated a feasibility study to investigate the technical aspects of measuring and transferring vibration, acceleration, temperature, and video data from a CubeSat to NASA Hanger AE on Cape Canaveral Air Force Station (CCAFS) a.k.a. Kennedy Space Center (KSC). This report provides a technical feasibility analysis to determine whether-or-not a specific set of NASA/LSP requirements can be accomplished. Our approach has been to provide a "notional" component layout to determine the feasibility of the NASA/LSP stakeholder requirements. The notional layout is used to consider component level technical issues such as size, weight, & power (SWaP), bandwidth, and other critical technical parameters. Even though the notional components may satisfy the stated requirements and thereby demonstrate feasibility, the notional layout is NOT considered a design since no component optimization and design trade-off analysis has taken place. This activity should be accomplished in an appropriate

  6. Chinese Carbon Dioxide Satellite (TanSat) Status and Plans

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Duan, M.; cai, Z.; Yang, D.; Lu, D.; Yin, Z.; Zheng, Y.; Yan, C.; Yang, Z.

    2012-12-01

    The Chinese carbon dioxide observation satellite (TanSat) project is the national high technology research and development program. It is funded by the ministry of science and technology of the people's republic of China and the Chinese Academy of Sciences. The TanSat will be launched in 2015, which is going to monitor the carbon dioxide in Sun-Synchronous orbit. The object of TanSat is to monitor XCO2 from space with precision of 1~4ppm. Two instruments will be onboard the TanSat, the main instrument is a high resolution grating spectrometer that measure reflected sunlight with the 0.76 μm O2 A-band and two CO2 bands at 1.61 and 2.06 μm, an airborne prototype of main instrument will be built and tested in the aircraft experiment. The second instrument is the Cloud and Aerosol Polarization Imager (CAPI), which is a wide field of view moderate resolution imaging spectrometer, it include 0.38, 0.67, 0.87, 1.375 and 1.64μm channels, with two polarization channels in 0.67μm and 1.64μm. A full physical optimal estimation method has being developed to retrieve the column-averaged CO2 dry air mole fraction (XCO2), and the data from CAPI will be used to correct cloud and aerosol interference. Currrently, the GOSAT data have been applied in the XCO2 retrieval system and reasonable results have been obtained. Global and regional surface CO2 flux will be derived from XCO2 observations with inverse modeling. Ground based validation stations are being established around China to observe CO2, Aerosol and Cloud. The CO2 observation consist of 3 Bruker IFS125 and 3 Optical Spectrum Analyzer over Beijing, Shenzhen, Shangdong, Inner Mongol, and Hainan Island, etc. Four phases of TanSat development is scheduled: design phase from Jan. 2011 to Aug. 2012, initial prototypes phase from Sept. 2012 to Sept. 2013, final prototypes phase from Oct. 2013 to Oct. 2014, launching and on-board testing phase from Nov. 2014 to June 2015.

  7. Pseudo LRM waveforms from CryoSat SARin acquisition

    NASA Astrophysics Data System (ADS)

    Scagliola, Michele; Fornari, Marco; Bouffard, Jerome; Parrinello, Tommaso; Féménias, Pierre

    2016-04-01

    CryoSat was launched on the 8th April 2010 and is the first European ice mission dedicated to the monitoring of precise changes in the thickness of polar ice sheets and floating sea ice. The main payload of CryoSat is a Ku-band pulsewidth limited radar altimeter, called SIRAL (Synthetic interferometric radar altimeter). When commanded in SARIn (synthetic aperture radar interferometry) mode, through coherent along-track processing of the returns received from two antennas, the interferometric phase related to the first arrival of the echo is used to retrieve the angle of arrival of the scattering in the across-track direction. When SIRAL operates in SAR or SARin mode, the obtained waveforms have an along-track resolution and a speckle reduction which is increased with respect to the pulse-limited waveforms. Anyway, in order to analyze the continuity of the geophysical retrieved parameters among different acquisition modes, techniques to transform SARin mode data to pseudo-LRM mode data are welcome. The transformation process is known as SAR reduction and it is worth recalling here that only approximate pseudo-LRM waveforms can be obtained in case of closed burst acquisitions, as SIRAL operates. A SAR reduction processing scheme has been developed to obtain pseudo-LRM waveforms from CryoSat SARin acquisition. As a trade-off between the along-track length on Earth surface contributing to one SARin pseudo-LRM waveform and the noisiness of the waveform itself, it has been chosen a SAR reduction approach based on the averaging of all the SARin echoes received each 20Hz, resulting in one pseudo-LRM waveform for each SARin burst given the SARin burst repetition period. SARin pseudo-LRM waveforms have been produced for CryoSat acquisition both on ice and sea surfaces, aiming at verifying the continuity of the retracked surface height over the ellipsoid between genuine LRM products and pseudo-LRM products. Moreover, the retracked height from the SARin pseudo-LRM has been

  8. CryoSat-2: A new perspective on the Cryosphere

    NASA Astrophysics Data System (ADS)

    Shepherd, A.; Armitage, T.; Briggs, K.; Flament, T.; Hogg, A. E.; McMillan, M.; Muir, A.; Ridout, A.; Sundal, A.; Tilling, R.; Wingham, D.

    2014-12-01

    CryoSat-2 is ESA's first satellite mission dedicated to measuring changes in the polar land ice and sea ice cover. Following its launch in April 2010, we have examined the performance of the instrument over the continental ice sheets of Antarctica and Greenland, the Artic Ocean, and, for the purposes of calibration, over the oceans. We have confirmed the engineering performance at system level of the interferometer demonstrating that it measures across-track surface slopes with a precision of 25 micro-radians and an accuracy of 10 micro-radians, greatly exceeding the pre-launch specifications (100 micro-radians). Over the polar ice sheets, we have examined the performance of the range estimation, and determined the range precision to be 19 cm RMS at 20 Hz. We have examined the retrieval of the phase information over the ice sheets, and found the phase estimates to be robust and little affected by the uncertain ice sheet topography. Based on the calibration of the interferometer, the contribution of the across track slope error is, at 0.4 mm, negligible. Over marine sea ice, we have verified the discrimination of sea ice and ocean lead returns using contemporaneous SAR imagery from ENVISAT, and we have estimated the precision of individual (20 Hz) measurements to be 2 cm. In summary, with the corrected data products, we are able to confirm that the system performance of CryoSat-2 will meet or exceed its specification over the continental and marine ice sheets. This presenetation sumamrises the key outcomes of the mission performance, and presents a series of example case studies where CryoSat-2 data have been applied to study changes in Earth's land and sea ice cover. We show that in 4 years CryoSat has been able to detect changes in the mass of the Antarctic and Greenland ice sheets with an accuracy comparable to that of the past 20 years of conventional satellite altimetry and that important changes have occured in these regions, we show that CryoSat has been able

  9. A review of planetary and space science projects presented at iCubeSat, the Interplanetary CubeSat Workshop

    NASA Astrophysics Data System (ADS)

    Johnson, Michael

    2015-04-01

    iCubeSat, the Interplanetary CubeSat Workshop, is an annual technical workshop for researchers working on an exciting new standardised platform and opportunity for planetary and space scientists. The first workshop was held in 2012 at MIT, 2013 at Cornell, 2014 at Caltech with the 2015 workshop scheduled to take place on the 26-27th May 2015 at Imperial College London. Mission concepts and flight projects presented since 2012 have included orbiters and landers targeting asteroids, the moon, Mars, Venus, Saturn and their satellites to perform science traditionally reserved for flagship missions at a fraction of their cost. Some of the first missions proposed are currently being readied for flight in Europe, taking advantage of multiple ride share launch opportunities and technology providers. A review of these and other interplanetary CubeSat projects will be presented, covering details of their science objectives, instrument capabilities, technology, team composition, budget, funding sources, and the other programattic elements required to implement this potentially revolutionary new class of mission.

  10. Phosphorylation of bamboo mosaic virus satellite RNA (satBaMV)-encoded protein P20 downregulates the formation of satBaMV-P20 ribonucleoprotein complex.

    PubMed

    Vijayapalani, Paramasivan; Chen, Jeff Chien-Fu; Liou, Ming-Ru; Chen, Hsin-Chuan; Hsu, Yau-Heiu; Lin, Na-Sheng

    2012-01-01

    Bamboo mosaic virus (BaMV) satellite RNA (satBaMV) depends on BaMV for its replication and encapsidation. SatBaMV-encoded P20 protein is an RNA-binding protein that facilitates satBaMV systemic movement in co-infected plants. Here, we examined phosphorylation of P20 and its regulatory functions. Recombinant P20 (rP20) was phosphorylated by host cellular kinase(s) in vitro, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and mutational analyses revealed Ser-11 as the phosphorylation site. The phosphor-mimic rP20 protein interactions with satBaMV-translated mutant P20 were affected. In overlay assay, the Asp mutation at S11 (S11D) completely abolished the self-interaction of rP20 and significantly inhibited the interaction with both the WT and S11A rP20. In chemical cross-linking assays, S11D failed to oligomerize. Electrophoretic mobility shift assay and subsequent Hill transformation analysis revealed a low affinity of the phospho-mimicking rP20 for satBaMV RNA. Substantial modulation of satBaMV RNA conformation upon interaction with nonphospho-mimic rP20 in circular dichroism analysis indicated formation of stable satBaMV ribonucleoprotein complexes. The dissimilar satBaMV translation regulation of the nonphospho- and phospho-mimic rP20 suggests that phosphorylation of P20 in the ribonucleoprotein complex converts the translation-incompetent satBaMV RNA to messenger RNA. The phospho-deficient or phospho-mimicking P20 mutant of satBaMV delayed the systemic spread of satBaMV in co-infected Nicotiana benthamiana with BaMV. Thus, satBaMV likely regulates the formation of satBaMV RNP complex during co-infection in planta. PMID:21965537

  11. Concepts for an Enhanced CubeSat GEO Space Situational Awareness Architecture

    NASA Astrophysics Data System (ADS)

    Morris, K.; Rice, C.

    2014-09-01

    With space becoming more congested, competitive, and contested, new space situational awareness architectures are required to maintain the US advantage in space. This, along with government budget concerns, requires new and potentially radical approaches for performing Space Situational Awareness (SSA). Previous studies have shown that CubeSats can fill holes in the GEO SSA architecture and provide point of light observations of objects. The next logical step is to develop a CubeSat constellation that provides complete coverage of the GEO belt while minimizing the cost to field the architecture. CubeSats provide value to the GEO SSA mission by hosting optical systems and taking pictures along the GEO belt, however, CubeSats do have limitations when it comes to mission assurance. Because of this, mission orbits must be chosen such that failed CubeSats do not become pieces of debris. In addition, recent advances in CubeSat propulsion systems open up new orbits and constellations due to the increased thrust and Delta V. Analyzing the CubeSat capabilities along with launch rideshare options determined the most cost effective architecture to provide high accuracy tracks to all objects at GEO with minimal gaps between observations. Several mission orbits are combined to provide the access and coverage required. The few launches direct to GEO can accommodate CubeSats that can be place in a GEO +500 km orbit. The CubeSats would image the GEO belt as they drift with respect to GEO performing the track and custody missions. More launches occur to the GEO transfer orbit during the and CubeSats ridesharing on these launches reside in an elliptical orbit with the apogee at GEO and the CubeSat propulsion system can be used to raise perigee to maintain a reasonable mission life. CubeSats in this orbit can image the GEO belt near apogee from different angles than the +500 km orbits that contributes to higher accuracy tracks. Finally, ridesharing as hosted payloads on commercial

  12. Diverse Attitudes to and Understandings of Spontaneous Awakening Trials (SAT): Results from a Statewide Quality Improvement Collaborative

    PubMed Central

    Miller, Melissa A; Krein, Sarah L; George, Christine T; Watson, Sam R; Hyzy, Robert C; Iwashyna, Theodore J

    2013-01-01

    Objective Spontaneous awakening trials (SATs) improve outcomes in mechanically ventilated patients, but implementation remains erratic. We examined variation in reported practice, prevalence of attitudes and fears regarding SATs, and organizational practices associated with routine implementation of SATs in an ICU quality improvement collaborative. Design Written survey. Setting Michigan Health and Hospital Association’s Keystone ICU, a quality improvement collaborative of 73 hospitals. Subjects Attendees of the yearly Keystone ICU meeting, January 2011, including nurses, physicians, hospital administrators, and other healthcare professionals. Intervention Respondents were asked about institutional characteristics, SAT practice, attitudes and barriers regarding SATs, and organizational cultural characteristics that might influence SAT practice. The association of organizational cultural characteristics and attitudes with reported SAT use was evaluated using logistic regression. Measurements and Main Results 319 participants attended the meeting. The survey response rate was 83.4%. Respondents reported wide variation in approach to SAT performance and patient selection. 48.6% of respondents reported regular SAT use, defined as >75% of mechanically ventilated patients undergoing SATs each day. In bivariable analysis, addressing sedation goals routinely in rounds and having SATs as part of unit culture were positively associated with regular SAT use, while the perception that SATs increased short term adverse effects, staff fears of SATs, and the perception that SATs are hard work were negatively associated with regular SAT use. In multivariable analysis, only addressing sedation in rounds (OR 2.85 [95%CI 1.55–5.23]), incorporation of SATs into unit culture (OR 3.36 [95% CI 1.75–6.43]), and the perception that SATs are hard work (OR 0.53 [95% CI 0.30–0.96]) remained statistically significantly associated with regular SAT use. Respondents in managerial

  13. From Napkin to Orbit in 9 Months; The TechEdSat Spacecraft Mission

    NASA Technical Reports Server (NTRS)

    Cohen, Aaron; Hoppins, Nicholas; Trinh, Greenfield; Schulte, Jan; Bruhn, Fredrik; Loefgren, Henrik; Selin, Per

    2013-01-01

    The TechEdSat spacecraft mission saw one of the fastest turn around times for concept through launch of a CubeSat. On 26 October 2011, John Hines sketched on a brown paper napkin the outline for which components would be in this 1U CubeSat, and how they would be stacked; 269 days later that spacecraft launched from Tanegashima Space Center aboard the HTV-3 ISS resupply mission, with a total development time of only eight months. TechEdSat was among the first of five CubeSats deployed from the ISS. The goals of the TechEdSat mission were to explore the use of the Space Plug-n-Play Architecture (SPA) in a CubeSat, and to evaluate Commercial Off The Shelf (COTS) space-to-space communication solutions. TechEdSat featured an array of processors from ÅAC Microtec including four NanoRTU's and the RTULite main processor, all communicating using the SPA-1 protocol. TechEdSat featured two primary payloads: an Iridium 9602 Modem, and a Quake Global Q1000 OrbComm modem. After a successful deployment on 4 October 2012 from the ISS, over 2000 packets of 122 bytes each (250 kB total) were received in the first four months of the mission. In this paper we discuss the challenges to rapid CubeSat development, the experience of having a CubeSat approved for deployment from the ISS, the ongoing results of the mission and lessons learned.

  14. Introduction of Chinese Carbon Dioxide Satellite (TanSat) Mission

    NASA Astrophysics Data System (ADS)

    Liu, Yi

    It is well known that the increase in atmospheric CO2 and CH4 (long-lived greenhouse gases; GHG) due to anthropogenic activity is the dominant process driving global climate change. Space-based measurements of GHGs with high precision, resolution, and global coverage are urgently needed to characterize the geographic distribution of their sources and sinks and quantify their roles in the atmospheric CO2 budget. As a large developing country, China has the highest level of GHG emissions. The Chinese government is seeking sustainable development and hence is trying to reduce GHG emissions. The ministry of science and technology of the people’s republic of China had started the Chinese carbon dioxide observation satellite (TanSat) mission 3 years ago, currently the science requirement review and preliminary design review phases had been finished. The prototype of 3 channel high resolution grating spectrometer for CO2 measurement has been manufactured and tested, and the Cloud and Aerosol Polarization Imager (CAPI) is manufactured on schedule. To support TanSat mission, a full physical optimal estimation method has being developed to retrieve the column-averaged CO2 dry air mole fraction (XCO2), and the GOSAT data have been applied in the XCO2 retrieval system and reasonable results have been achieved. Global and regional CO2 flux will be derived from XCO2 observations with inverse modeling- Chinese Carbon Cycle Data Assimilation System (Tan-Tracker). Ground based measurement stations have being established around China to validate satellite observation. They consist of 3 Bruker IFS125, 3 Optical Spectrum Analyzer (OSA) and other instruments over different parts of China. TanSat is scheduled to be launched at the end of 2015.

  15. Thermal Analysis of Iodine Satellite (iSAT)

    NASA Technical Reports Server (NTRS)

    Mauro, Stephanie

    2015-01-01

    This paper presents the progress of the thermal analysis and design of the Iodine Satellite (iSAT). The purpose of the iSAT spacecraft (SC) is to demonstrate the ability of the iodine Hall Thruster propulsion system throughout a one year mission in an effort to mature the system for use on future satellites. The benefit of this propulsion system is that it uses a propellant, iodine, that is easy to store and provides a high thrust-to-mass ratio. The spacecraft will also act as a bus for an earth observation payload, the Long Wave Infrared (LWIR) Camera. Four phases of the mission, determined to either be critical to achieving requirements or phases of thermal concern, are modeled. The phases are the Right Ascension of the Ascending Node (RAAN) Change, Altitude Reduction, De-Orbit, and Science Phases. Each phase was modeled in a worst case hot environment and the coldest phase, the Science Phase, was also modeled in a worst case cold environment. The thermal environments of the spacecraft are especially important to model because iSAT has a very high power density. The satellite is the size of a 12 unit cubesat, and dissipates slightly more than 75 Watts of power as heat at times. The maximum temperatures for several components are above their maximum operational limit for one or more cases. The analysis done for the first Design and Analysis Cycle (DAC1) showed that many components were above or within 5 degrees Centigrade of their maximum operation limit. The battery is a component of concern because although it is not over its operational temperature limit, efficiency greatly decreases if it operates at the currently predicted temperatures. In the second Design and Analysis Cycle (DAC2), many steps were taken to mitigate the overheating of components, including isolating several high temperature components, removal of components, and rearrangement of systems. These changes have greatly increased the thermal margin available.

  16. Launch and Early Orbit Operations for CryoSat-2

    NASA Astrophysics Data System (ADS)

    Mardel, Nic; Marchese, Franco

    2010-12-01

    CryoSat-2 was launched from Baikonur on 8th of April 2010 aboard a modified Dnepr ICBM, the so-called SS18 Satan. Following the ascent and separation from the launch vehicle the Flight Operations Segment (FOS) in ESOC, Darmstadt started the operations to configure the satellite into the correct mode to acquire science; switching on units, configuring software and ensuring that the satellite health and performance was as expected. This paper will describe the operations performed by the FOS during the first weeks in orbit, including the unexpected problems encountered, their implications and solutions.

  17. CubeSat Remote Sensing: A Survey of Current Capabilities

    NASA Astrophysics Data System (ADS)

    Hegel, D.

    2014-12-01

    Recent years have seen dramatic growth in the availability and capability of very small satellites for atmospheric sensing, and other space-based science, as the simplicity of integration and low cost of these platforms enables projects that would otherwise be prohibitively expensive, or demand excessive expertise/infrastructure to execute. This paper surveys the current state-of-the-art for CubeSat performance, including pointing accuracy, geolocation, available power, and data downlink capacity. Applications for up-coming missions, such as CeREs, MinXSS, and HARP will also be discussed.

  18. Diagnosing AIRS Sampling with CloudSat Cloud Classes

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric; Yue, Qing; Guillaume, Alexandre; Kahn, Brian

    2011-01-01

    AIRS yield and sampling vary with cloud state. Careful utilization of collocated multiple satellite sensors is necessary. Profile differences between AIRS and ECMWF model analyses indicate that AIRS has high sampling and excellent accuracy for certain meteorological conditions. Cloud-dependent sampling biases may have large impact on AIRS L2 and L3 data in climate research. MBL clouds / lower tropospheric stability relationship is one example. AIRS and CloudSat reveal a reasonable climatology in the MBL cloud regime despite limited sampling in stratocumulus. Thermodynamic parameters such as EIS derived from AIRS data map these cloud conditions successfully. We are working on characterizing AIRS scenes with mixed cloud types.

  19. Enhanced electromagnetic sounding of Europa's ocean using CubeSats

    NASA Astrophysics Data System (ADS)

    Crary, Frank; Holmes, Justin; Malaspina, David; Mason, James; Ranquist, Drake; Schiller, Quintin; Sturner, Andrew; Kohnert, Rick

    2015-04-01

    Diagnosing the properties of Europa's ocean is a key objective of the planned Europa Clipper mission. Magnetic field measurements reveal the inductive signatures of the ocean, but also contain perturbations from the magnetospheric interaction with Europa. Determining the properties of the ocean using this technique requires separating the induced field from that of the magnetospheric interaction. One solution is to use magnetometer-bearing CubeSats to make simultaneous flybys along trajectories separated from that of the Europa Clipper. We describe a concept for such nanosatellites and how they could greatly enhance the precision of induced magnetic field ocean soundings.

  20. A CubeSat deployable solar panel system

    NASA Astrophysics Data System (ADS)

    McGuire, Thomas; Hirsch, Michael; Parsons, Michael; Leake, Skye; Straub, Jeremy

    2016-05-01

    The power usage of CubeSat's onboard systems has increased with the complexity of the systems included. This paper presents a deployment system design which creates a plane of solar panels to collect energy. This allows more panels to be in direct normal sunlight at any given point (in conjunction with the onboard attitude determination and control system), facilitating increased power generation. The deployable system is comprised of a printed circuit board (holding the solar cells) which is attached to an aluminum hinge. The efficacy of this approach for power generation and its simplicity, as compared to other prospective approaches, are assessed herein.

  1. Preliminary thermal design of the COLD-SAT spacecraft

    NASA Technical Reports Server (NTRS)

    Arif, Hugh

    1991-01-01

    The COLD-SAT free-flying spacecraft was to perform experiments with LH2 in the cryogenic fluid management technologies of storage, supply and transfer in reduced gravity. The Phase A preliminary design of the Thermal Control Subsystem (TCS) for the spacecraft exterior and interior surfaces and components of the bus subsystems is described. The TCS was composed of passive elements which were augmented with heaters. Trade studies to minimize the parasitic heat leakage into the cryogen storage tanks are described. Selection procedure for the thermally optimum on-orbit spacecraft attitude was defined. TRASYS-2 and SINDA'85 verification analysis was performed on the design and the results are presented.

  2. Technology maturation process: the NASA Strategic Astrophysics Technology (SAT) program

    NASA Astrophysics Data System (ADS)

    Perez, Mario R.; Pham, Bruce T.; Lawson, Peter R.

    2014-08-01

    In 2009 the Astrophysics Division at NASA Headquarters established the Strategic Astrophysics Technology (SAT) solicitation as a new technology maturation program to fill the needed gap for mid-Technology Readiness Level (TRL) levels (3≤ TRL <6). In three full proposal selection cycles since the inception of this program, more than 40 investigations have been selected, many meritorious milestones have been met and advances have been achieved. In this paper, we review the process of establishing technology priorities, the management of technology advancements and milestones, and the incipient success of some of these investigations in light of the need of future space missions.

  3. Solving Open Job-Shop Scheduling Problems by SAT Encoding

    NASA Astrophysics Data System (ADS)

    Koshimura, Miyuki; Nabeshima, Hidetomo; Fujita, Hiroshi; Hasegawa, Ryuzo

    This paper tries to solve open Job-Shop Scheduling Problems (JSSP) by translating them into Boolean Satisfiability Testing Problems (SAT). The encoding method is essentially the same as the one proposed by Crawford and Baker. The open problems are ABZ8, ABZ9, YN1, YN2, YN3, and YN4. We proved that the best known upper bounds 678 of ABZ9 and 884 of YN1 are indeed optimal. We also improved the upper bound of YN2 and lower bounds of ABZ8, YN2, YN3 and YN4.

  4. LARES/WEBER-SAT and the equivalence principle

    NASA Astrophysics Data System (ADS)

    Iorio, L.

    2007-11-01

    It has often been claimed that the proposed Earth artificial satellite LARES/WEBER-SAT —whose primary goal is, in fact, the measurement of the general relativistic Lense-Thirring effect at a some percent level— would allow greatly improving, among (many) other things, the present-day (10-13) level of accuracy in testing the equivalence principle as well. Recent claims point towards even two orders of magnitude better, i.e. 10-15. In this letter we show that such a goal is, in fact, unattainable by many orders of magnitude being, instead, the achievable level ≈10-9.

  5. The SBP-SAT technique for initial value problems

    NASA Astrophysics Data System (ADS)

    Lundquist, Tomas; Nordström, Jan

    2014-08-01

    A detailed account of the stability and accuracy properties of the SBP-SAT technique for numerical time integration is presented. We show how the technique can be used to formulate both global and multi-stage methods with high order of accuracy for both stiff and non-stiff problems. Linear and non-linear stability results, including A-stability, L-stability and B-stability are proven using the energy method for general initial value problems. Numerical experiments corroborate the theoretical properties.

  6. A Comparison of an Introductory Course to SAT/ACT Scores in Predicting Student Performance

    ERIC Educational Resources Information Center

    Marsh, Crystale M.; Vandehey, Michael A.; Diekhoff, George M.

    2008-01-01

    We assessed students in General Psychology classes and examined their SAT/ACT scores, GPAs, and attempted and earned hours. Exams in General Psychology were superior to the SAT/ACT in predicting GPA, supporting the use of an introductory course as a "gateway" for identifying at-risk students and engaging them in academic services. (Contains 3…

  7. CloudSat Preps for Launch at Vandenberg Air Force Base, CA

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The CloudSat spacecraft sits encapsulated within its Boeing Delta launch vehicle dual payload attach fitting at Vandenberg Air Force Base, Calif. CloudSat will share its ride to orbit late next month with NASA's CALIPSO spacecraft. The two spacecraft are designed to reveal the secrets of clouds and aerosols.

  8. PowerSat: A technology demonstration of a solar power satellite

    NASA Technical Reports Server (NTRS)

    Sigler, Douglas L. (Editor); Riedman, John; Duracinski, Jon; Edwards, Joe; Brown, Garry; Webb, Ron; Platzke, Mike; Yuan, Xiaolin; Rogers, Pete; Khan, Afsar

    1994-01-01

    PowerSat is a preliminary design strategy for microwave wireless power transfer of solar energy. Solar power satellites convert solar power into microwave energy and use wireless power transmission to transfer the power to the Earth's surface. The PowerSat project will show how new developments in inflatable technology can be used to deploy solar panels and phased array antennas.

  9. Growth Determination for Genetic Engineered SAT Type Foot-and-Mouth Disease Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foot-and-mouth disease virus (FMDV) is endemic throughout large parts of Africa where six of the seven serotypes, viz. A, C, O, SAT (South Africa Territories) 1, 2, 3, occur. The SAT types, usually confined to sub-Saharan Africa, show marked genomic and antigenic variation, with the ID-coding sequen...

  10. The Relationship of High School Graduation Exams to Graduation Rates and SAT Scores

    ERIC Educational Resources Information Center

    Marchant, Gregory J.; Paulson, Sharon E.

    2005-01-01

    The current study examined the effect of high school graduation exams on states' graduation rates, states' aggregated SAT scores, and individual students' SAT scores. Three data sources were used: One source identified states requiring a standardized test for graduation; the NCES provided state aggregated data on graduation rates for the class of…

  11. Life with the SAT: Assessing Our Young People and Our Times.

    ERIC Educational Resources Information Center

    Hanford, George H.

    The history and nature of the Scholastic Aptitude Test (SAT) and issues that continue to be raised in the context of its use are discussed by a former president of the College Entrance Examination Board. This book provides insights into the changing role of college admissions testing since World War II; and considers the role of the SAT in…

  12. The SAT Trap. Why Do We Make So Much of One 3-Hour Test?

    ERIC Educational Resources Information Center

    Adelman, Clifford

    1999-01-01

    The Scholastic Assessment Tests (SAT) measures students' general learned abilities, but student test performance is influenced as much by family environment as it is by formal education. Many colleges use SAT scores in admissions decisions. Students would be far better served if there was a concentration on other ways of predicting success in…

  13. Non-"g" Residuals of the SAT and ACT Predict Specific Abilities

    ERIC Educational Resources Information Center

    Coyle, Thomas R.; Purcell, Jason M.; Snyder, Anissa C.; Kochunov, Peter

    2013-01-01

    This research examined whether non-"g" residuals of the SAT and ACT subtests, obtained after removing g, predicted specific abilities. Non-"g" residuals of the verbal and math subtests of the SAT and ACT were correlated with academic (verbal and math) and non-academic abilities (speed and shop), both based on the Armed Services Vocational Aptitude…

  14. Tooth and Nail: A Novel Approach to the New SAT. A Harvest Test Preparation Book.

    ERIC Educational Resources Information Center

    Elster, Charles Harrington; Elliot, Joseph

    "Tooth and Nail" is a novel that teaches vocabulary for the Scholastic Aptitude Test (SAT) in context. Rather than presenting lists of vocabulary words to memorize, the mystery novel presents some 1,200 words, which have appeared in past SATs, in context. The story, about going off to college, features a literacy treasure hunt involving rare books…

  15. Does Quantity Equal Quality?: The Relationship between Length of Response and Scores on the SAT Essay

    ERIC Educational Resources Information Center

    Kobrin, Jennifer L.; Deng, Hui; Shaw, Emily J.

    2007-01-01

    This study was designed to address two frequent criticisms of the SAT essay--that essay length is the best predictor of scores, and that there is an advantage in using more "sophisticated" examples as opposed to personal experience. The study was based on 2,820 essays from the first three administrations of the new SAT. Each essay was coded for…

  16. Why Do Women Have Lower Average SAT-Math Scores than Men?

    ERIC Educational Resources Information Center

    Navarro, Cristina

    A study involving 716 male and 1,113 female first-year students admitted to the University of Delaware in the fall of 1985 was conducted to investigate the differential performance of men and women on the mathematics section of the Scholastic Aptitude Test (SAT). Data collected included SAT math scores; gender; and number of years of high school…

  17. Socio-Economic Family Background Still a Significant Influence on SAT Scores.

    ERIC Educational Resources Information Center

    Hawkins, B. Denise

    1993-01-01

    An analysis of trends in Scholastic Aptitude Test (SAT) scores looks at SAT verbal and mathematics averages by racial group and gender, reports racial group percentages of examinees by state, and charts relationships between ethnic group, parental education, family income, student years of postsecondary study, and scores. (MSE)

  18. The SAT® and SAT Subject Tests™: Discrepant Scores and Incremental Validity. Research Report 2012-2

    ERIC Educational Resources Information Center

    Kobrin, Jennifer L.; Patterson, Brian F.

    2012-01-01

    This study examines student performance on the SAT and SAT Subject Tests in order to identify groups of students who score differently on these two tests, and to determine whether certain demographic groups score higher on one test compared to the other. Discrepancy scores were created to capture individuals' performance differences on the…

  19. Reconsidering the SAT-I for College Admissions: Analysis of Alternate Predictors of College Success.

    ERIC Educational Resources Information Center

    Armstrong, William B.; Carty, Heidi M.

    The University of California is engaged in the elimination of the Scholastic Assessment Test I (SAT-I) Verbal and Mathematics tests as a requirement for freshman admission. Opponents of the SAT-I argue that the tests do not measure the outcomes of the high school curriculum and hence do not reflect student learning in secondary school. Proponents…

  20. The Relationship between SAT Scores and Retention to the Third Year: 2006 Cohort. Statistical Report

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2010-01-01

    Results show that SAT performance is related to third year retention rates. Even after controlling for student and institutional characteristics, returners had higher SAT total scores than non-returners, and the performance gap is not due to differences in the demographic makeup of the two groups. Furthermore, while differences in retention can be…

  1. An Open-Source GUI for Calculating Icy Moon Tidal Stresses Using SatStress

    NASA Astrophysics Data System (ADS)

    Kay, J. P.; Kattenhorn, S. A.

    2010-03-01

    We have used the open-source program SatStress to develop a graphic user interface (GUI) for calculating tidal stresses on the surface of a satellite with both elastic and viscoelastic rheology. SatStress GUI will eventually be open-source.

  2. WindSat passive microwave polarimetric observations of soil moisture and land variables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    WindSat is a spaceborne multi-frequency polarimetric microwave radiometer and has the potential of contributing to the retrieval of land variables and complementing efforts directed at the Aqua AMSR-E. In this study, a previously established algorithm was applied to WindSat data to estimate global s...

  3. Observations of Land Surface Passive Polarimetry with the WindSat Instrument

    Technology Transfer Automated Retrieval System (TEKTRAN)

    WindSat provides an opportunity to explore the passive microwave polarimetric signatures of land surfaces. In order to accommodate the large sensor footprint, large homogeneous regions with unique features were used. These included forest, rangeland, desert and agricultural conditions. WindSat obser...

  4. Gum chewing improves adolescents’ math performance in an SAT preparatory course

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of the current study was to determine the effect of gum chewing on students’ performance in a preparatory course for the Scholastic Aptitude Test (SAT). A total of 182 adolescents enrolled in an SAT preparatory class were randomized into one of two treatments: 1) gum chewing condition (G...

  5. The Rainbow Project: Enhancing the SAT through Assessments of Analytical, Practical, and Creative Skills

    ERIC Educational Resources Information Center

    Sternberg, Robert J.

    2006-01-01

    This article describes the formulation and execution of the Rainbow Project, Phase I, funded by the College Board. Past data suggest that the SAT is a good predictor of performance in college. But in terms of the amount of variance explained by the SAT, there is room for improvement, as there would be for virtually any single test battery. Phase I…

  6. NASAs EDSN Aims to Overcome the Operational Challenges of CubeSat Constellations and Demonstrate an Economical Swarm of 8 CubeSats Useful for Space Science Investigations

    NASA Technical Reports Server (NTRS)

    Smith, Harrison Brodsky; Hu, Steven Hung Kee; Cockrell, James J.

    2013-01-01

    Operators of a constellation of CubeSats have to confront a number of daunting challenges that can be cost prohibitive, or operationally prohibitive, to missions that could otherwise be enabled by a satellite constellation. Challenges including operations complexity, intersatellite communication, intersatellite navigation, and time sharing tasks between satellites are all complicated by operating with the usual CubeSat size, power, and budget constraints. EDSN pioneers innovative solutions to these problems as they are presented on the nano-scale satellite platform.

  7. Deciphering Staphylococcus sciuri SAT-17 Mediated Anti-oxidative Defense Mechanisms and Growth Modulations in Salt Stressed Maize (Zea mays L.).

    PubMed

    Akram, Muhammad S; Shahid, Muhammad; Tariq, Mohsin; Azeem, Muhammad; Javed, Muhammad T; Saleem, Seemab; Riaz, Saba

    2016-01-01

    Soil salinity severely affects plant nutrient use efficiency and is a worldwide constraint for sustainable crop production. Plant growth-promoting rhizobacteria, with inherent salinity tolerance, are able to enhance plant growth and productivity by inducing modulations in various metabolic pathways. In the present study, we reported the isolation and characterization of a salt-tolerant rhizobacterium from Kallar grass [Leptochloa fusca (L.) Kunth]. Sequencing of the 16S rRNA gene revealed its lineage to Staphylococcus sciuri and it was named as SAT-17. The strain exhibited substantial potential of phosphate solubilization as well as indole-3-acetic acid production (up to 2 M NaCl) and 1-aminocyclopropane-1-carboxylic acid deaminase activity (up to 1.5 M NaCl). Inoculation of a rifampicin-resistant derivative of the SAT-17 with maize, in the absence of salt stress, induced a significant increase in plant biomass together with decreased reactive oxygen species and increased activity of cellular antioxidant enzymes. The derivative strain also significantly accumulated nutrients in roots and shoots, and enhanced chlorophyll and protein contents in comparison with non-inoculated plants. Similar positive effects were observed in the presence of salt stress, although the effect was more prominent at 75 mM in comparison to higher NaCl level (150 mM). The strain survived in the rhizosphere up to 30 days at an optimal population density (ca. 1 × 10(6) CFU mL(-1)). It was concluded that S. sciuri strain SAT-17 alleviated maize plants from salt-induced cellular oxidative damage and enhanced growth. Further field experiments should be conducted, considering SAT-17 as a potential bio-fertilizer, to draw parallels between PGPR inoculation, elemental mobility patterns, crop growth and productivity in salt-stressed semi-arid and arid regions. PMID:27375588

  8. Deciphering Staphylococcus sciuri SAT-17 Mediated Anti-oxidative Defense Mechanisms and Growth Modulations in Salt Stressed Maize (Zea mays L.)

    PubMed Central

    Akram, Muhammad S.; Shahid, Muhammad; Tariq, Mohsin; Azeem, Muhammad; Javed, Muhammad T.; Saleem, Seemab; Riaz, Saba

    2016-01-01

    Soil salinity severely affects plant nutrient use efficiency and is a worldwide constraint for sustainable crop production. Plant growth-promoting rhizobacteria, with inherent salinity tolerance, are able to enhance plant growth and productivity by inducing modulations in various metabolic pathways. In the present study, we reported the isolation and characterization of a salt-tolerant rhizobacterium from Kallar grass [Leptochloa fusca (L.) Kunth]. Sequencing of the 16S rRNA gene revealed its lineage to Staphylococcus sciuri and it was named as SAT-17. The strain exhibited substantial potential of phosphate solubilization as well as indole-3-acetic acid production (up to 2 M NaCl) and 1-aminocyclopropane-1-carboxylic acid deaminase activity (up to 1.5 M NaCl). Inoculation of a rifampicin-resistant derivative of the SAT-17 with maize, in the absence of salt stress, induced a significant increase in plant biomass together with decreased reactive oxygen species and increased activity of cellular antioxidant enzymes. The derivative strain also significantly accumulated nutrients in roots and shoots, and enhanced chlorophyll and protein contents in comparison with non-inoculated plants. Similar positive effects were observed in the presence of salt stress, although the effect was more prominent at 75 mM in comparison to higher NaCl level (150 mM). The strain survived in the rhizosphere up to 30 days at an optimal population density (ca. 1 × 106 CFU mL-1). It was concluded that S. sciuri strain SAT-17 alleviated maize plants from salt-induced cellular oxidative damage and enhanced growth. Further field experiments should be conducted, considering SAT-17 as a potential bio-fertilizer, to draw parallels between PGPR inoculation, elemental mobility patterns, crop growth and productivity in salt-stressed semi-arid and arid regions. PMID:27375588

  9. The promise of scientific CubeSat missions

    NASA Astrophysics Data System (ADS)

    Moretto Jorgensen, Therese

    In 2008, The US National Science Foundation (NSF) started a program in support of CubeSat-based science missions for space weather and atmospheric research. This program implements a new and very different approach to providing needed scientific space measurements. It builds on recent engineering and system developments of CubeSat technology that have established the technical feasibility of tiny spacecraft missions that can be launched as secondary payloads at very low cost and rapid time scales as they pose virtually no risk to the launch vehicle or its primary payload. This makes space measurements achievable within the scope of the traditional NSF grants programs and greatly enhances the participation of the larger university community in space activities. Equally importantly, such projects offer unique opportunities for hands-on education and training for students and young professionals in aerospace engineering and experimental space science. Currently, the program supports 6 projects, the first one of which is scheduled for launch in May 2010. The presentation will describe the creation of the program, current projects, and future plans and will discuss successes and challenges encountered so far.

  10. Characterization of Debris from the DebriSat Hypervelocity Test

    NASA Technical Reports Server (NTRS)

    Rivero, M.; Kleespies, J.; Patankar, K.; Fitz-Coy, N.; Liou, J.-C.; Sorge, M.; Huynh, T.; Opiela, J.; Krisko, P.; Cowardin, H.

    2015-01-01

    The DebriSat project is an effort by NASA and the DoD to update the standard break-up model for objects in orbit. The DebriSat object, a 56 kg representative LEO satellite, was subjected to a hypervelocity impact in April 2014. For the hypervelocity test, the representative satellite was suspended within a "soft-catch" arena formed by polyurethane foam panels to minimize the interactions between the debris generated from the hypervelocity impact and the metallic walls of the test chamber. After the impact, the foam panels and debris not caught by the panels were collected and shipped to the University of Florida where the project has now advanced to the debris characterization stage. The characterization effort has been divided into debris collection, measurement, and cataloguing. Debris collection and cataloguing involves the retrieval of debris from the foam panels and cataloguing the debris in a database. Debris collection is a three-step process: removal of loose debris fragments from the surface of the foam panels; X-ray imaging to identify/locate debris fragments embedded within the foam panel; extraction of the embedded debris fragments identified during the X-ray imaging process. As debris fragments are collected, they are catalogued into a database specifically designed for this project. Measurement involves determination of size, mass, shape, material, and other physical properties and well as images of the fragment. Cataloguing involves a assigning a unique identifier for each fragment along with the characterization information.

  11. Multi-sensor Observations of the SpinSat Satellite

    NASA Astrophysics Data System (ADS)

    Hall, D.

    The Naval Research Laboratory developed and launched the spherical SpinSat satellite to accomplish two primary goals: 1) study the performance of a new class of micro-thrusters, and 2) provide a calibrated drag experiment to characterize Earth's upper atmosphere during the current period of relatively high solar activity. The 55.9 cm diameter aluminum sphere is equipped with a set of Electrically-Controlled Solid Propellant (ESP) thrusters, oriented to allow both translational and spin-up/spin-down maneuvers. To facilitate remote observations of the satellite's spin rate, the sphere's exterior features a reflectance pattern much like that of a beach-ball, as well as an ensemble of light-emitting diodes (LEDs) arranged along a meridian (i.e., a line of longitude) which can be turned on for brief periods. The Air Force Research Laboratory has conducted optical observations of SpinSat from several ground-based sensors, and more are planned. The observational goals include: 1) obtaining time-resolved, multi-band measurements of the satellite actively firing its micro-thrusters, 2) characterizing the detectability and spatial/temporal morphology of the ESP thruster plumes, 3) measuring the spin rate of the satellite with the LEDs turned on, ideally before and after a spin rate adjustment maneuver, and 4) measuring the spin rate of the satellite in its completely inactive mode, using only passive observations of reflected light and/or thermal emissions.

  12. South Atlantic anomaly and CubeSat design considerations

    NASA Astrophysics Data System (ADS)

    Fennelly, Judy A.; Johnston, William R.; Ober, Daniel M.; Wilson, Gordon R.; O'Brien, T. Paul; Huston, Stuart L.

    2015-09-01

    Effects of the South Atlantic Anomaly (SAA) on spacecraft in low Earth orbit (LEO) are well known and documented. The SAA exposes spacecraft in LEO to high dose of ionizing radiation as well as higher than normal rates of Single Event Upsets (SEU) and Single Event Latch-ups (SEL). CubeSats, spacecraft built around 10 x 10 x 10 cm cubes, are even more susceptible to SEUs and SELs due to the use of commercial off-the-shelf components for electronics and payload instrumentation. Examination of the SAA using both data from the Defense Meteorological Satellite Program (DMSP) and a new set of models for the flux of particles is presented. The models, AE9, AP9, and SPM for energetic electrons, energetic protons and space plasma, were developed for use in space system design. These models introduce databased statistical constraints on the uncertainties from measurements and climatological variability. Discussion of the models' capabilities and limitations with regard to LEO CubeSat design is presented.

  13. Validation of CryoSat-2 derived lake levels

    NASA Astrophysics Data System (ADS)

    Nielsen, Karina; Stenseng, Lars; Andersen, Ole; Villadsen, Heidi; Knudsen, Per

    2015-04-01

    The SIRAL altimeter on-board the ESA satellite CryoSat-2 is the first radar altimeter that is capable of operating in synthetic aperture radar (SAR) mode. The SAR technology provides a much higher along-track resolution compared to conventional altimetry. The higher resolution makes it possible to accurately monitor much smaller water bodies than previously. In this study, which is part of the FP7 project Land and Ocean take up from Sentinel-3 (LOTUS), we examine and validate Cryosat-2 derived lake levels and as a reference we compare our results with lake levels based on Envisat data. As a test case we consider 5 lakes; Vänern (Sweden), Okeechobee (Florida, US), Arresø, Mossø, and Skanderborgsø (Denmark), which are ranging from approximately 9 km2 to 5655 km2. We estimate the along-track precision and the accuracy by validating the estimated lake levels with gauge data from Okeechobee and Vänern. We find that the precision based on CryoSat-2 increase significantly for small lakes compared to Envisat. Despite the spatially varying lake crossings, Cryosat-2 is able to provide lake level time series of a quality that is comparable to or better than Envisat. Hence, these results demonstrate the promising possibilities of the upcoming mission Sentinel-3, which potentially will be able to provide accurate time series for small lakes.

  14. The COLD-SAT Experiment for Cryogenic Fluid Management Technology

    NASA Technical Reports Server (NTRS)

    Schuster, J. R.; Wachter, J. P.; Vento, D. M.

    1990-01-01

    Future national space transportation missions will depend on the use of cryogenic fluid management technology development needs for these missions. In-space testing will be conducted in order to show low gravity cryogenic fluid management concepts and to acquire a technical data base. Liquid H2 is the preferred test fluid due to its propellant use. The design of COLD-SAT (Cryogenic On-orbit Liquid Depot Storage, Acquisition, and Transfer Satellite), an Expendable Launch Vehicle (ELV) launched orbital spacecraft that will perform subcritical liquid H2 storage and transfer experiments under low gravity conditions is studied. An Atlas launch vehicle will place COLD-SAT into a circular orbit, and the 3-axis controlled spacecraft bus will provide electric power, experiment control, and data management, attitude control, and propulsive accelerations for the experiments. Low levels of acceleration will provide data on the effects that low gravity might have on the heat and mass transfer processes used. The experiment module will contain 3 liquid H2 tanks; fluid transfer, pressurization and venting equipment; and instrumentation.

  15. COLD-SAT: A technology satellite for cryogenic experimentation

    NASA Technical Reports Server (NTRS)

    Arif, H.; Kroeger, E. W.

    1989-01-01

    NASA-Lewis (LeRC) is involved in the development and validation of analytical models which describe the fluid dynamic and thermodynamic processes associated with the storage, acquisition and transfer of subcritical cryogenic fluids in low gravity. Four concurrent studies, including one in-house at LeRC, are underway to determine the feasibility of performing model validation experiments aboard a free-flying spacecraft (S/C) called Cryogenic On-Orbit Liquid Depot-Storage, Acquisition and Transfer (COLD-SAT), using liquid hydrogen as the cryogen. The technology requirements for the experiments are described along with the initial LeRC concepts for the S/C and an experiment subsystem comprising of cryogenic tankage (a supply dewar and three receiver tanks), gas pressurization bottles (both helium and autogenous hydrogen), their associated plumbing, and instrumentation for data collection. Experiments were categorized into enabling/high priority Class 1 technologies and component/system Class 2 demonstrations. As initially envisioned by LeRC, COLD-SAT would have had a 1997 launch aboard a Delta-2 for a 6 month active lifetime in a 925 km orbit with a pseudo-inertial attitude.

  16. COLD-SAT: An orbital cryogenic hydrogen technology experiment

    NASA Technical Reports Server (NTRS)

    Schuster, J. R.; Wachter, Joseph P.; Powers, Albert G.

    1989-01-01

    The COLD-SAT spacecraft will perform subcritical liquid hydrogen storage and transfer experiments under low-gravity conditions to provide engineering data for future space transportation missions. Consisting of an experiment module mated to a spacecraft bus, COLD-SAT will be placed in an initial 460 km circular orbit by an Atlas I commercial launch vehicle. After deployment, the three-axis-controlled spacecraft bus will provide electric power, experiment control and data management, communications, and attitude control along with propulsive acceleration levels ranging from 10(-6) to 10(-4)g. These accelerations are an important aspect of some of the experiments, as it is desired to know the effects that low gravity levels might have on the heat and mass transfer processes involved. The experiment module will contain the three liquid hydrogen tanks, valves, pressurization equipment, and instrumentation. At launch all the hydrogen will be in the largest tank, which has helium-purged MLI and is loaded and topped off by the hydrogen tanking system used for the Centaur upper stage of the Atlas. The two smaller tanks will be utilized in orbit for performing some of the experiments. The experiments are grouped into two classes on the basis of their priority, and include six regarded as enabling technology and nine regarded as enhancing technology.

  17. COLD-SAT - A technology satellite for cryogenic experimentation

    NASA Technical Reports Server (NTRS)

    Arif, H.; Kroeger, E. W.

    1990-01-01

    NASA-Lewis (LeRC) is involved in the development and validation of analytical models which describe the fluid dynamic and thermodynamic processes associated with the storage, acquisition and transfer of subcritical cryogenic fluids in low gravity. Four concurrent studies, including one in-house at LeRC, are underway to determine the feasibility of performing model validation experiments aboard a free-flying spacecraft (S/C) called Cryogenic On-Orbit Liquid Depot-Storage, Acquisition and Transfer (COLD-SAT), using liquid hydrogen as the cryogen. The technology requirements for the experiments are described along with the initial LeRC concepts for the S/C and an experiment subsystem comprising of cryogenic tankage (a supply dewar and three receiver tanks), gas pressurization bottles (both helium and autogenous hydrogen), their associated plumbing, and instrumentation for data collection. Experiments were categorized into enabling/high priority Class 1 technologies and component/system Class 2 demonstrations. As initially envisioned by LeRC, COLD-SAT would have had a 1997 launch aboard a Delta-2 for a 6 month active lifetime in a 925 km orbit with a pseudo-inertial attitude.

  18. COLD-SAT - An orbital cryogenic hydrogen technology experiment

    NASA Technical Reports Server (NTRS)

    Schuster, J. R.; Wachter, Joseph P.; Powers, Albert G.

    1989-01-01

    The COLD-SAT spacecraft will perform subcritical liquid hydrogen storage and transfer experiments under low-gravity conditions to provide engineering data for future space transportation missions. Consisting of an experiment module mated to a spacecraft bus, COLD-SAT will be placed in an initial 460 km circular orbit by an Atlas I commercial launch vehicle. After deployment, the three-axis-controlled spacecraft bus will provide electric power, experiment control and data management, communications, and attitude control along with propulsive acceleration levels ranging from 10 (-6) to 10(-4) g. These accelerations are an important aspect of some of the experiments, as it is desired to know the effects that low gravity levels might have on the heat and mass transfer processes involved. The experiment module will contain the three liquid hydrogen tanks, valves, pressurization equipment, and instrumentation. At launch all the hydrogen will be in the largest tank, which has helium-purged MLI and is loaded and topped off by the hydrogen tanking system used for the Centaur upper stage of the Atlas. The two smaller tanks will be utilized in orbit for performing some of the experiments. The experiments are grouped into two classes on the basis of their priority, and include six regarded as enabling technology and nine regarded as enhancing technology.

  19. Report: antibiotic production by thermophilic Bacillus specie SAT-4.

    PubMed

    Muhammad, Syed Aun; Ahmad, Safia; Hameed, Abdul

    2009-07-01

    Production of antimicrobial compounds seems to be a general phenomenon for most bacteria. The prevalence of antimicrobial resistance among key microbial pathogens is increasing at an alarming rate worldwide. Current solutions involve development of a more rationale approach to antibiotic use and discover of new antimicrobials. Bacillus species produce a large number of biological compounds active against bacteria, fungi, protozoa and viruses. The process of production usually involves screening of wide range of microorganisms, testing and modification. Production is carried out using fermentation. Thermophilic spore-forming, gram positive, motile rod bacterial strains were isolated from the Thar Desserts, Sindh Province, Pakistan. These strains were screened and checked for antibacterial activity. The best activity was observed by SAT4 against Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeroginosa. The activity was only observed against gram positive bacteria and no activity was seen against Pseudomonas aeroginosa. Thermophilic Bacillus specie SAT4 was found to be active in the fermentation process to produce the antimicrobial agents. Further optimizations of different conditions (time of incubation, media, pH, glucose concentrations, nitrogen concentrations, and temperature) for antimicrobial production by the selected bacterial strain was performed. Agar diffusion assay was performed to evaluate the antibacterial activity. Optimum conditions for the production of antimicrobials by selected isolate were observed to be 48 hour, pH 5, temperature 55 degrees C, 2% glucose and 1.5% nitrogen concentration. This newly isolated bacterial strain has great potential for antimicrobial production at industrial scale. PMID:19553186

  20. Changes in Ocean Wind Retrieval Performance During the WindSat Mission

    NASA Astrophysics Data System (ADS)

    Bettenhausen, M. H.; Gaiser, P. W.; Adams, I. S.; Truesdale, D.

    2014-12-01

    Numerous improvements have been made to WindSat ground data processing software and retrieval algorithms since the initial evaluations of WindSat capabilities were published in 2006. These improvements include higher resolution retrievals, improved wind vector ambiguity selection, improved instrument characterization, better brightness temperature calibration and improved high wind speed retrievals. We briefly describe some of these improvements and provide statistical comparisons of the current WindSat ocean vector wind products to the older versions of the WindSat products. We also present comparisons for individual wind fields including examples of gap wind events and cyclonic storms. Limitations of the WindSat products and the underlying causes such as resolution and rain effects will be discussed.

  1. Effects of a hyperbaric environment on subcutaneous adipose tissue topography (SAT-top).

    PubMed

    Möller, Reinhard; Horejsi, Renate; Tafeit, Erwin; Fraidl, Michaela; Dietmaier, Gabriele; Anegg, Udo; Klemen, Huberta; Wallner-Liebmann, Sandra

    2010-12-01

    The physiological reactions of the body in scuba diving situation can be simulated in a pressure chamber by increasing the ambient pressure. In this study the influence of a hyperbaric environment of 6 bar on the changes of the subcutaneous adipose tissue (SAT) thicknesses on different body sites in 68 voluntary men with undersea diving experience was investigated. Measurements of SAT-topography (SAT-Top) were performed with the optical device Lipometer before and after hyperbaric exposure. We observed a significant increase of the SAT-layers of the upper body zones, upper abdomen (+24.5%), lower abdomen (+21%) and front chest (+19%) after hyperbaric exposure. This increase of volume can be assumed to the nitrogen accumulation in fat cells at increased ambient pressures. In conclusion we describe for the first time in detail the influence of a hyperbaric environment on quantitative and topographic changes of SAT. PMID:21874714

  2. SmallSats, Iodine Propulsion Technology, Applications to Low-Cost Lunar Missions, and the Iodine Satellite (iSAT) Project

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.

    2014-01-01

    Closing Remarks: ?(1) SmallSats hold significant potential for future low cost high value missions; (2) Propulsion remains a key limiting capability for SmallSats that Iodine can address: High ISP * Density for volume constrained spacecraft; Indefinite quiescence, unpressurized and non-hazardous as a secondary payload; (3) Iodine enables MicroSat and SmallSat maneuverability: Enables transfer into high value orbits, constellation deployment and deorbit; (4) Iodine may enable a new class of planetary and exploration class missions: Enables GTO launched secondary spacecraft to transit to the moon, asteroids, and other interplanetary destinations for approximately 150 million dollars full life cycle cost including the launch; (5) ESPA based OTVs are also volume constrained and a shift from xenon to iodine can significantly increase the transfer vehicle change in volume capability including transfers from GTO to a range of Lunar Orbits; (6) The iSAT project is a fast pace high value iodine Hall technology demonstration mission: Partnership with NASA GRC and NASA MSFC with industry partner - Busek; (7) The iSAT mission is an approved project with PDR in November of 2014 and is targeting a flight opportunity in FY17.

  3. High Data Rates for AubieSat-2 A & B, Two CubeSats Performing High Energy Science in the Upper Atmosphere

    NASA Technical Reports Server (NTRS)

    Sims, William H.

    2015-01-01

    This paper will discuss a proposed CubeSat size (3 Units / 6 Units) telemetry system concept being developed at Marshall Space Flight Center (MSFC) in cooperation with Auburn University. The telemetry system incorporates efficient, high-bandwidth communications by developing flight-ready, low-cost, PROTOFLIGHT software defined radio (SDR) payload for use on CubeSats. The current telemetry system is slightly larger in dimension of footprint than required to fit within a 0.75 Unit CubeSat volume. Extensible and modular communications for CubeSat technologies will provide high data rates for science experiments performed by two CubeSats flying in formation in Low Earth Orbit. The project is a collaboration between the University of Alabama in Huntsville and Auburn University to study high energy phenomena in the upper atmosphere. Higher bandwidth capacity will enable high-volume, low error-rate data transfer to and from the CubeSats, while also providing additional bandwidth and error correction margin to accommodate more complex encryption algorithms and higher user volume.

  4. Validity of the SAT® for Predicting Fourth-Year Grades: 2006 SAT Validity Sample. Statistical Report 2011-7

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2006-01-01

    The College Board formed a research consortium with four-year colleges and universities to build a national higher education database with the primary goal of validating the SAT®, which is used in college admission and consists of three sections: critical reading (SAT-CR), mathematics (SAT-M) and writing (SAT-W). This report builds on a body of…

  5. Propulsion System and Orbit Maneuver Integration in CubeSats: Trajectory Control Strategies Using Micro Ion Propulsion

    NASA Technical Reports Server (NTRS)

    Hudson, Jennifer; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Propulsion System and Orbit Maneuver Integration in CubeSats project aims to solve the challenges of integrating a micro electric propulsion system on a CubeSat in order to perform orbital maneuvers and control attitude. This represents a fundamentally new capability for CubeSats, which typically do not contain propulsion systems and cannot maneuver far beyond their initial orbits.

  6. The SAT[R] I and High School Grades: Utility in Predicting Success in College. Research Notes.

    ERIC Educational Resources Information Center

    Camara, Wayne J.; Echternacht, Gary

    For more than 70 years researchers have studied the validity of the Scholastic Assessment Test I (SAT I) and its predecessor, the Scholastic Aptitude Test, through hundreds of validity studies conducted at various colleges using the SAT in their admission process. The majority of these studies use high school records and SAT scores as predictors…

  7. The Relationship between SAT® Scores and Retention to the Second Year: 2008 SAT Validity Sample. Statistical Report 2012-1

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2012-01-01

    The College Board formed a research consortium with four-year colleges and universities to build a national higher education database with the primary goal of validating the revised SAT®, which consists of three sections: critical reading (SAT-CR), mathematics (SAT-M), and writing (SAT-W), for use in college admission. A study by Mattern and…

  8. Evaluating SAT® II: Mathematics IC Items in the SAT I Population. Research Report No. 2005-3

    ERIC Educational Resources Information Center

    Liu, Jinghua; Schuppan, Fred; Walker, Michael E.

    2005-01-01

    This study explored whether the addition of the items with more advanced math content to the SAT Reasoning Test™ (SAT®) would impact test-taker performance. Two sets of SAT math equating sections were modified to form four subforms each. Different numbers of items with advanced content, taken from the SAT II: Mathematics Level IC Test (Math IC),…

  9. CubeSat Cloud: A framework for distributed storage, processing and communication of remote sensing data on cubesat clusters

    NASA Astrophysics Data System (ADS)

    Challa, Obulapathi Nayudu

    CubeSat Cloud is a novel vision for a space based remote sensing network that includes a collection of small satellites (including CubeSats), ground stations, and a server, where a CubeSat is a miniaturized satellite with a volume of a 10x10x10 cm cube and has a weight of approximately 1 kg. The small form factor of CubeSats limits the processing and communication capabilities. Implemented and deployed CubeSats have demonstrated about 1 GHz processing speed and 9.6 kbps communication speed. A CubeSat in its current state can take hours to process a 100 MB image and more than a day to downlink the same, which prohibits remote sensing, considering the limitations in ground station access time for a CubeSat. This dissertation designs an architecture and supporting networking protocols to create CubeSat Cloud, a distributed processing, storage and communication framework that will enable faster execution of remote sensing missions on CubeSat clusters. The core components of CubeSat Cloud are CubeSat Distributed File System, CubeSat MapMerge, and CubeSat Torrent. The CubeSat Distributed File System has been created for distributing of large amounts of data among the satellites in the cluster. Once the data is distributed, CubeSat MapReduce has been created to process the data in parallel, thereby reducing the processing load for each CubeSat. Finally, CubeSat Torrent has been created to downlink the data at each CubeSat to a distributed set of ground stations, enabling faster asynchronous downloads. Ground stations send the downlinked data to the server to reconstruct the original image and store it for later retrieval. Analysis of the proposed CubeSat Cloud architecture was performed using a custom-designed simulator, called CubeNet and an emulation test bed using Raspberry Pi devices. Results show that for cluster sizes ranging from 5 to 25 small satellites, faster download speeds up to 4 to 22 times faster - can be achieved when using CubeSat Cloud, compared to a

  10. Interpretation of MODIS Cloud Images by CloudSat/CALIPSO Cloud Vertical Profiles

    NASA Astrophysics Data System (ADS)

    Wang, T.; Fetzer, E. J.; Wong, S.; Yue, Q.

    2015-12-01

    Clouds observed by passive remote-sensing imager (Aqua-MODIS) are collocated to cloud vertical profiles observed by active profiling sensors (CloudSat radar and CALIPSO lidar) at the pixel-scale. By comparing different layers of cloud types classified in the 2B-CLDCLASS-LIDAR product from CloudSat+CALIPSO to those cloud properties observed by MODIS, we evaluate the occurrence frequencies of cloud types and cloud-overlap in CloudSat+CALIPSO for each MODIS cloud regime defined by cloud optical depth (τ) and cloud-top pressure (P) histograms. We find that about 70% of MODIS clear sky agrees with the clear category in CloudSat+CALIPSO; whereas the remainder is either single layer (~25%) cirrus (Ci), low-level cumulus (Cu), stratocumulus (Sc), or multi-layer (<5%) clouds in CloudSat+CALIPSO. Under MODIS cloudy conditions, 60%, 28%, and 8% of the occurrences show single-, double-, and triple-layer clouds, respectively in CloudSat+CALIPSO. When MODIS identifies single-layer clouds, 50-60% of the MODIS low-level clouds are categorized as stratus (Sc) in CloudSat+CALIPSO. Over the tropics, ~70% of MODIS high and optically thin clouds (considered as cirrus in the histogram) is also identified as Ci in CloudSat+CALIPSO, and ~40% of MODIS high and optically thick clouds (considered as convective in the histogram) agrees with CloudSat+CALIPSO deep convections (DC). Over mid-latitudes these numbers drop to 45% and 10%, respectively. The best agreement occurs in tropical single-layer cloud regimes, where 90% of MODIS high-thin clouds are identified as Ci by CloudSat+CALIPSO and 60% of MODIS high-thick clouds are identified as DC. Worst agreement is found for multi-layer clouds, where cirrus on top of low- and mid-level clouds in MODIS are frequently categorized as high-thick clouds by passive imaging - among these only 5-12% are DC in CloudSat+CALIPSO. It is encouraging that both MODIS low-level clouds (regardless of optical thickness) and high-level thin clouds are consistently

  11. A two-dimensional cadmium(II) polymer based on nicotinic acid and thiocyanate ligands.

    PubMed

    Zhou, Lin; Wang, Hui-Ting

    2015-09-01

    A cadmium-thiocyanate complex, poly[[bis(nicotinic acid-κN)di-μ-thiocyanato-κ(2)N:S;κ(2)S:N-cadmium(II)] monohydrate], {[Cd(NCS)2(C6H5NO2)2]·H2O}n, was synthesized by the reaction of nicotinic acid, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, each Cd(II) cation is in a distorted octahedral coordination environment, coordinated by the N and S atoms of nicotinic acid and thiocyanate ligands. Neighbouring Cd(II) cations are linked together by thiocyanate bridges to form a two-dimensional network. Hydrogen-bond interactions between the uncoordinated solvent water molecules and the organic ligands result in the formation of the three-dimensional supramolecular network. PMID:26322616

  12. Sialic Acid Transport Contributes to Pneumococcal Colonization ▿

    PubMed Central

    Marion, Carolyn; Burnaugh, Amanda M.; Woodiga, Shireen A.; King, Samantha J.

    2011-01-01

    Streptococcus pneumoniae is a major cause of pneumonia and meningitis. Airway colonization is a necessary precursor to disease, but little is known about how the bacteria establish and maintain colonization. Carbohydrates are required as a carbon source for pneumococcal growth and, therefore, for colonization. Free carbohydrates are not readily available in the naso-oropharynx; however, N- and O-linked glycans are common in the airway. Sialic acid is the most common terminal modification on N- and O-linked glycans and is likely encountered frequently by S. pneumoniae in the airway. Here we demonstrate that sialic acid supports pneumococcal growth when provided as a sole carbon source. Growth on sialic acid requires import into the bacterium. Three genetic regions have been proposed to encode pneumococcal sialic acid transporters: one sodium solute symporter and two ATP binding cassette (ABC) transporters. Data demonstrate that one of these, satABC, is required for transport of sialic acid. A satABC mutant displayed significantly reduced growth on both sialic acid and the human glycoprotein alpha-1. The importance of satABC for growth on human glycoprotein suggests that sialic acid transport may be important in vivo. Indeed, the satABC mutant was significantly reduced in colonization of the murine upper respiratory tract. This work demonstrates that S. pneumoniae is able to use sialic acid as a sole carbon source and that utilization of sialic acid is likely important during pneumococcal colonization. PMID:21189320

  13. CpSAT-1, a transcribed satellite sequence from the codling moth, Cydia pomonella.

    PubMed

    Věchtová, Pavlína; Dalíková, Martina; Sýkorová, Miroslava; Žurovcová, Martina; Füssy, Zoltán; Zrzavá, Magda

    2016-08-01

    Satellite DNA (satDNA) is a non-coding component of eukaryotic genomes, located mainly in heterochromatic regions. Relevance of satDNA began to emerge with accumulating evidence of its potential yet hardly comprehensible role that it can play in the genome of many organisms. We isolated the first satDNA of the codling moth (Cydia pomonella, Tortricidae, Lepidoptera), a species with holokinetic chromosomes and a single large heterochromatic element, the W chromosome in females. The satDNA, called CpSAT-1, is located on all chromosomes of the complement, although in different amounts. Surprisingly, the satellite is almost missing in the heterochromatic W chromosome. Additionally, we isolated mRNA from all developmental stages (1st-5th instar larva, pupa, adult), both sexes (adult male and female) and several tissues (Malpighian tubules, gut, heart, testes, and ovaries) of the codling moth and showed the CpSAT-1 sequence was transcribed in all tested samples. Using CpSAT-1 specific primers we amplified, cloned and sequenced 40 monomers from cDNA and gDNA, respectively. The sequence analysis revealed a high mutation rate and the presence of potentially functional motifs, mainly in non-conserved regions of the monomers. Both the chromosomal distribution and the sequence analysis suggest that CPSAT-1 has no function in the C. pomonella genome. PMID:27236660

  14. Orthogonal factor coefficient development of subcutaneous adipose tissue topography (SAT-Top) in girls and boys.

    PubMed

    Tafeit, E; Möller, R; Sudi, K; Horejsi, R; Berg, A; Reibnegger, G

    2001-05-01

    The new optical device Lipometer allows noninvasive, quick, and safe determination of the thickness of subcutaneous adipose tissue (SAT) layers (in mm) at any site of the human body. The specification of 15 evenly distributed body sites enables the precise measurement of subcutaneous body fat distribution, so-called subcutaneous adipose tissue topography (SAT-Top). SAT-Top was measured in 980 children aged 7-19 years. In this paper we describe the degree to which SAT-Top body sites are intercorrelated. We consider whether a meaningful reduction of data is possible using factor analysis, which factors can be extracted, and how SAT-Top data of children can be added to a factor value plot, depicting the essential results of age-dependent subcutaneous fat development. SAT layers situated on the same body area provide correlation coefficients up to +r = 0.91. Two factors are extracted: factor 1, containing all upper body sites (from neck to hip); and factor 2, consisting of all leg body sites. When all 980 children are divided into three age groups in a factor value plot, the first age group (7-11 years) shows almost equal SAT-Top development in boys and girls. Afterwards, for the consecutive age groups 2 (11-15 years) and 3 (15-19 years), the age-dependent subcutaneous fat development of boys and girls progresses into nearly orthogonal directions. PMID:11309750

  15. EarthSat spring wheat yield system test 1975

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results of an operational test of the EarthSat System during the period 1 June - 30 August 1975 over the spring wheat regions of North Dakota, South Dakota, and Minnesota are presented. The errors associated with each sub-element of the system during the operational test and the sensitivity of the complete system and each major functional sub-element of the system to the observed errors were evaluated. Evaluations and recommendations for future operational users of the system include: (1) changes in various system sub-elements, (2) changes in the yield model to affect improved accuracy, (3) changes in the number of geobased cells needed to develop an accurate aggregated yield estimate, (4) changes associated with the implementation of future operational satellites and data processing systems, and (5) detailed system documentation.

  16. Implementation and validation of a CubeSat laser transmitter

    NASA Astrophysics Data System (ADS)

    Kingsbury, R. W.; Caplan, D. O.; Cahoy, K. L.

    2016-03-01

    The paper presents implementation and validation results for a CubeSat-scale laser transmitter. The master oscillator power amplifier (MOPA) design produces a 1550 nm, 200mW average power optical signal through the use of a directly modulated laser diode and a commercial fiber amplifier. The prototype design produces high-fidelity M-ary pulse position modulated (PPM) waveforms (M=8 to 128), targeting data rates > 10 Mbit/s while meeting a constraining 8W power allocation. We also present the implementation of an avalanche photodiode (APD) receiver with measured transmitter-to-receiver performance within 3 dB of theory. Via loopback, the compact receiver design can provide built-in self-test and calibration capabilities, and supports incremental on-orbit testing of the design.

  17. ATMOSUV-CanSat (Atmospheric Thunderstorms's Monitor Optical Signal & UV)

    NASA Astrophysics Data System (ADS)

    Calvo, David; Navarro-González, Javier; Carrió, Fernando; Blay, Pere; Espinós, Héctor; Connell, Paul; Eyles, Chris; Reglero, Víctor

    2014-05-01

    The ATMOSUV-CanSat is a small instrument aimed to study the Optical and UV signal in a TGF (Terrestrial Gamma-ray Flash) process, as a complementary ground monitor facility in the study of thunderstorms at high altitude in the atmosphere. The main goal is to take complementary data to that of the MXGS/ASIM (Modular X-ray and Gamma-ray Sensor in the Atmosphere-Space Interactions Monitor) mission, taken from the ISS (International Space Station). The detector is planed to be launch in a baloon during severe thunderstorms and take measurements of air conditions and to perform fast imaging with high temporal accuracy. We expect to measure UV emision, optical signal, temperature, presure, and accurate 3D location, with FPGA controlled high velocity imaging devices and sensors.

  18. Efficient SAT Techniques for Relative Encoding of Permutations with Constraints

    NASA Astrophysics Data System (ADS)

    Velev, Miroslav N.; Gao, Ping

    We present new techniques for relative SAT encoding of permutations with constraints, resulting in improved scalability compared to the previous approach by Prestwich, when applied to searching for Hamiltonian cycles. We observe that half of the ordering variables and two-thirds of the transitivity constraints can be eliminated. We exploit minimal enumeration of transitivity, based on 12 triangulation heuristics, and 11 heuristics for selecting the first node in the Hamiltonian cycle. We propose the use of inverse transitivity constraints. We achieve 3 orders of magnitude average speedup on satisfiable random graphs from the phase transition region, 2 orders of magnitude average speedup on unsatisfiable random graphs, and up to 4 orders of magnitude speedup on satisfiable structured graphs from the DIMACS graph coloring instances.

  19. The Scanning Ionospheric Photometer for CubeSats

    NASA Astrophysics Data System (ADS)

    Fish, C. S.; Crowley, G.; Pilinski, M.; Azeem, I.; Reynolds, A.; Noto, J.; Migliozzi, M.; Doe, R.

    2015-12-01

    Sponsored by the Air Force, our team is developing a system capable of providing night-time images of the ionosphere from a 6U CubeSat. Called SIPS (Scanning Ionospheric Photometer System), it integrates a photometer with a scanning mirror providing almost continuous monitoring of the night-side ionosphere. SIPS will be able to monitor features such as plasma irregularities, which can have deleterious effects on satellite positioning and HF communications. SIPS will help understand the nature of geospace perturbations as well as predict space weather. Requiring minimal power and volume, SIPS enables a number of research and science missions for NSF and NASA, as well as space situational awareness operational missions for the Air Force, that can be conducted from low cost to access to space platforms. In this paper we review the novel sensor observation technique and the modular design which makes SIPS compatible with nano and μsatellites, enabling big missions from small packages.

  20. Satellite Telemetry Analyzer Tool for DubaiSat-1

    NASA Astrophysics Data System (ADS)

    Al Hammadi, Omran; Amin, Amel; Al Rais, Adnan; Alloghani, Majid

    2013-08-01

    LEO Satellite telemetry is transmitted to the ground station once it passes over it. This telemetry contains readings of different parameters of various subsystems within the spacecraft. These readings must be analyzed on daily basis to assure the satellite health. Detection of any anomaly occurred or a prediction of possible future problem is a time-consuming task and requires a lot of manpower resources. Satellite operators and engineers need a system that visualizes these massive amounts of readings and automatically detects any anomaly occurred. The Ground Systems Development of EIAST has developed a system that analyzes the received telemetry from DubaiSat-1. It searches for already archived telemetry and stores it into the system database. The end-user interface enhances the telemetry visualization by plotting different parameters of a subsystem during different satellite operation modes. It also clearly notifies the operators of the satellite if any value exceeds its maximum level or drops down to its minimum value.

  1. Pi-Sat: A Low Cost Small Satellite and Distributed Spacecraft Mission System Test Platform

    NASA Technical Reports Server (NTRS)

    Cudmore, Alan

    2015-01-01

    Current technology and budget trends indicate a shift in satellite architectures from large, expensive single satellite missions, to small, low cost distributed spacecraft missions. At the center of this shift is the SmallSatCubesat architecture. The primary goal of the Pi-Sat project is to create a low cost, and easy to use Distributed Spacecraft Mission (DSM) test bed to facilitate the research and development of next-generation DSM technologies and concepts. This test bed also serves as a realistic software development platform for Small Satellite and Cubesat architectures. The Pi-Sat is based on the popular $35 Raspberry Pi single board computer featuring a 700Mhz ARM processor, 512MB of RAM, a flash memory card, and a wealth of IO options. The Raspberry Pi runs the Linux operating system and can easily run Code 582s Core Flight System flight software architecture. The low cost and high availability of the Raspberry Pi make it an ideal platform for a Distributed Spacecraft Mission and Cubesat software development. The Pi-Sat models currently include a Pi-Sat 1U Cube, a Pi-Sat Wireless Node, and a Pi-Sat Cubesat processor card.The Pi-Sat project takes advantage of many popular trends in the Maker community including low cost electronics, 3d printing, and rapid prototyping in order to provide a realistic platform for flight software testing, training, and technology development. The Pi-Sat has also provided fantastic hands on training opportunities for NASA summer interns and Pathways students.

  2. Mothership - Affordable Exploration of Planetary Bodies through Individual Nano-Sats and Swarms

    NASA Astrophysics Data System (ADS)

    DiCorcia, James D.; Ernst, Sebastian M.; Grace, J. Mike; Gump, David P.; Lewis, John S.; Foulds, Craig F.; Faber, Daniel R.

    2015-04-01

    One concept to enable broad participation in the scientific exploration of small bodies is the Mothership mission architecture which delivers third-party nano-sats, experiments, and sensors to a near Earth asteroid or comet. Deep Space Industries' Mothership service includes delivery of nano-sats, communication to Earth, and visuals of the asteroid surface and surrounding area. It allows researchers to house their instruments in a low-cost nano-sat platform that does not require the high-performance propulsion or deep space communication capabilities that otherwise would be required for a solo asteroid mission. This enables organizations with relatively low operating budgets to closely examine an asteroid with highly specialized sensors of their own choosing, while the nano-sats can be built or commissioned by a variety of smaller institutions, companies, or agencies. In addition, the Mothership and its deployed nano-sats can offer a platform for instruments which need to be distributed over multiple spacecraft. The Mothership is designed to carry 10 to 12 nano-sats, based upon a variation of the Cubesat standard, with some flexibility on the specific geometry. The Deep Space Nano-Sat reference design is a 14.5 cm cube, which accomodates the same volume as a traditional 3U Cubesat. This design was found to be more favorable for deep space due to its thermal characteristics. The CubeSat standard was originally designed with operations in low Earth orbit in mind. By deliberately breaking the standard, Deep Space Nano-Sats offer better performance with less chance of a critical malfunction in the more hostile deep space environment. The first mission can launch as early as Q4 2017, with subsequent, regular launches through the 2020's.

  3. Whole-gene sequencing investigation of SAT1 in attempted suicide.

    PubMed

    Monson, Eric T; de Klerk, Kelly; Gaynor, Sophia C; Wagner, Alex H; Breen, Marie E; Parsons, Meredith; Casavant, Thomas L; Zandi, Peter P; Potash, James B; Willour, Virginia L

    2016-09-01

    Suicidal behavior imposes a tremendous cost, with current US estimates reporting approximately 1.3 million suicide attempts and more than 40,000 suicide deaths each year. Several recent research efforts have identified an association between suicidal behavior and the expression level of the spermidine/spermine N1-acetyltransferase 1 (SAT1) gene. To date, several SAT1 genetic variants have been inconsistently associated with altered gene expression and/or directly with suicidal behavior. To clarify the role SAT1 genetic variation plays in suicidal behavior risk, we present a whole-gene sequencing effort of SAT1 in 476 bipolar disorder subjects with a history of suicide attempt and 473 subjects with bipolar disorder but no suicide attempts. Agilent SureSelect target enrichment was used to sequence all exons, introns, promoter regions, and putative regulatory regions identified from the ENCODE project within 10 kb of SAT1. Individual variant, haplotype, and collapsing variant tests were performed. Our results identified no variant or assessed region of SAT1 that showed a significant association with attempted suicide, nor did any assessment show evidence for replication of previously reported associations. Overall, no evidence for SAT1 sequence variation contributing to the risk for attempted suicide could be identified. It is possible that past associations of SAT1 expression with suicidal behavior arise from variation not captured in this study, or that causal variants in the region are too rare to be detected within our sample. Larger sample sizes and broader sequencing efforts will likely be required to identify the source of SAT1 expression level associations with suicidal behavior. © 2016 Wiley Periodicals, Inc. PMID:27229768

  4. First results on GlioLab/GlioSat Precursors Missions

    NASA Astrophysics Data System (ADS)

    Cappelletti, Chantal; Notarangelo, Angelo; Demoss, Darrin; Carella, Massimo

    2012-07-01

    Since 2009 GAUSS group is involved in a joint collaboration with Morehead State University (MSU) Space Science Center and IRCCS Casa Sollievo della Sofferenza (CSS) research labs with the aim to design a biomedical project in order to investigate if the combined effects of microgravity conditions and ionizing radiation increase or decrease the survival rate of cancer cells. The biological sample consists of Glioblastoma cancer cell line ANGM-CSS. Glioblastoma is a kind of cancer that can be treated after surgery only by radiotherapy using ionizing radiation. This treatment, anyway, results in a very low survival rate. This project uses different university space platforms: a CubeLab, named GlioLab, on board the International Space Station and the university microsatellite UniSat-5 designed by GAUSS. In addition a GlioLab/GlioSat precursor experiment has already flown two times with the Space Shuttle during the missions STS-134 and STS-135. The phase 0 or the precursor of GlioLab uses a COTS system, named Liquid Mixing Apparatus (LMA), to board the biological samples inside the Space Shuttle for thirty day . The LMA allows to board liquids inside a vial but is not equipped with environment control system. After landing the samples were investigated by researchers at CSS in Italy and at MSU in Kentucky. This paper deals with the experimental set up and the results obtained during the STS-134 and STS-135 missions and with the new evidences on the behavior of this kind of cancer. In particular the results obtained on the DNA analysis give a confirmation of the original idea of GLioLab/Gliosat project justifying the development of the two systems.

  5. Development of Chinese Carbon Dioxide Satellite (TanSat)

    NASA Astrophysics Data System (ADS)

    Yi, Liu; Cai, Zhaonan; Yang, Dongxu; Duan, Minzheng; Lv, Daren; Yin, Zengshan; Zhang, Yonghe; Yang, Zhongdong; Zhang, Xingying; Zheng, Yuquan; Yan, Changxiang

    2013-04-01

    The Chinese carbon dioxide observation satellite (TanSat) project is the national high technology research and development program. It is funded by the ministry of science and technology of the people's republic of China and the Chinese Academy of Sciences. The TanSat is going to monitor the carbon dioxide in Sun-Synchronous orbit with XCO2 precision of 1~4ppm over regional scale. Two detectors are under design, the main instrument is a high resolution grating spectrometer that measure reflected sunlight with the 0.76 μm O2 A-band and two CO2 bands at 1.61 and 2.06 μm, the second one is the Cloud and Aerosol Polarization Imager (CAPI), which is a wide field of view moderate resolution imaging spectrometer, it include 0.38, 0.67, 0.87, 1.375 and 1.64μm channels, with two polarization channels in 0.67μm and 1.64μm. A full physical optimal estimation method has being developed to retrieve the column-averaged CO2 dry air mole fraction (XCO2), and the data from CAPI will be used to correct cloud and aerosol interference. Global and regional surface CO2 flux will be derived from XCO2 observations with inverse modeling. Ground based validation network are being established around China. The CO2 observation consist of 3 Bruker IFS125 and 3 Optical Spectrum Analyzer over Beijing, Shenzhen, Shangdong, Inner Mongol, and Hainan Island, etc. Currently, we are passing through the preliminary design review and will finish critical design review at the end of 2014, satellite readiness review and launching will be scheduled from Dec. 2014 to June 2015.

  6. Globally Gridded Satellite (GridSat) Observations for Climate Studies

    NASA Technical Reports Server (NTRS)

    Knapp, Kenneth R.; Ansari, Steve; Bain, Caroline L.; Bourassa, Mark A.; Dickinson, Michael J.; Funk, Chris; Helms, Chip N.; Hennon, Christopher C.; Holmes, Christopher D.; Huffman, George J.; Kossin, James P.; Lee, Hai-Tien; Loew, Alexander; Magnusdottir, Gudrun

    2012-01-01

    Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them: there is no central archive of geostationary data for all international satellites, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multi-satellite climate studies. The International Satellite Cloud Climatology Project set the stage for overcoming these issues by archiving a subset of the full resolution geostationary data at approx.10 km resolution at 3 hourly intervals since 1983. Recent efforts at NOAA s National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in the netCDF format using standards that permit a wide variety of tools and libraries to quickly and easily process the data. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

  7. Substituting SAT® II: Subject Tests for SAT I: Reasoning Test: Impact on Admitted Class Composition and Quality. Research Report No. 2001-3. ETS RR-01-07

    ERIC Educational Resources Information Center

    Bridgeman, Brent; Burton, Nancy; Cline, Frederick

    2001-01-01

    Using data from a sample of 10 colleges at which most students had taken both SAT I: Reasoning Test and SAT II: Subject Tests, the authors simulated the effects of making selection decisions using SAT II scores in place of SAT I scores. Specifically, they treated the students in each college as forming the applicant pool for a more select college,…

  8. SAT predicts GPA better for high ability subjects: Implications for Spearman’s Law of Diminishing Returns

    PubMed Central

    Coyle, Thomas; Snyder, Anissa; Pillow, David; Kochunov, Peter

    2011-01-01

    This research examined the predictive validity of the SAT (formerly, the Scholastic Aptitude Test) for high and low ability groups. SAT scores and college GPAs were obtained from the 1997 National Longitudinal Survey of Youth. Subjects were classified as high or low ability by g factor scores from the Armed Services Vocational Aptitude Battery. SAT correlations with GPA were higher for high than low ability subjects. SAT g loadings (i.e., SAT correlations with g) were equivalent for both groups. This is the first study to show that the predictive validity of the SAT varies for ability groups that differ in g. The results contradict a presumption, based on Spearman’s Law of Diminishing Returns, that a test’s predictive validity should be lower for high ability subjects. Further research is needed to identify factors that contribute to the predictive validity of the SAT for groups that differ in g. PMID:21562615

  9. On-orbit low gravity cryogenic scientific investigations using the COLD-SAT Satellite

    NASA Technical Reports Server (NTRS)

    Bailey, W. J.

    1990-01-01

    The Cryogenic On-Orbit Liquid Depot Storage, Acquisition and Transfer (COLD-SAT) Satellite is an experimental spacecraft designed to investigate the systems and technologies required for an efficient, effective, and reliable management of cryogenic fluids in reduced-gravity space environment. This paper defines the technology needs and the accompanying experimental three-month baseline mission of the COLD-SAT Satellite; describes the experiment subsystems, major features, and rationale for satisfying primary and secondary experimental requirements, using LH2 as the test fluid; and presents the conceptual design of the COLD-SAT spacecraft subsystems which support the on-orbit experiment.

  10. Global Hydrometeor Occurrence as Observed by CloudSAT: Initial Observations from Summer 2006

    SciTech Connect

    Mace, Gerald G.; Marchand, Roger T.; Zhang, Qiuqing; Stephens, Graeme L.

    2007-05-08

    Measurements of global hydrometeor coverage and occurrence frequencies as observed by the cloud radar on CloudSat are summarized using data collected during Summer 2006. CloudSat was launched on 28 April 2006 and began collecting data routinely on 7 June 2006. In this article we document the distribution of cloudiness from the ITCZ to the Polar regions as observed by CloudSat during the first summer of operations. The overall global hydrometeor coverage as observed by CloudSat is found to be 0.506. The vertical distribution of zonally averaged hydrometeor occurrence shows the relationship of clouds with components of the atmospheric general circulation such as the Hadley Cell, the ubiquitous storms over the Southern Ocean, and the subtropical stratocumulus regimes.

  11. Pulsed Plasma Propulsion - Making CubeSat Missions Beyond Low Earth Orbit Possible

    NASA Astrophysics Data System (ADS)

    Northway, P.

    2015-12-01

    As CubeSat missions become more and more popular means of scientific exploration of space, the current direction of interest is to utilize them in areas beyond low earth orbit. The University of Washington CubeSat program focuses on examining possible mission scenarios in addition to technology development and integration. Specifically, we are developing an inert CubeSat propulsion system in the form of a pulsed plasma thruster (PPT) capable of orbit maneuvers. Such a system would allow for missions at the Earth beyond LEO, extended missions at the Moon, and even missions at Europa, when assisted to the Jovian system. We will discuss how starting with a CubeSat design using PPTs for orbital maneuvers, other developing compact technology can be adapted to create a full suite of systems that would meet the requirements for a mission traveling outside low earth orbit.

  12. Attitude Control System for Low-Speed CubeSat Centrifuge to Simulate Asteroid Surface Conditions

    NASA Astrophysics Data System (ADS)

    Saumil, S.; Cannady, A.; Alizadeh, I.; Thangavelautham, J.; Asphaug, E.

    2015-01-01

    AOSat is a 3U CubeSat based centrifuge that will be launched into low Earth orbit in the 2015-2016 timeframe. This unique platform poses some fundamental challenges and opportunities in attitude control system development.

  13. River flood events in Thailand and Bangladesh observed by CryoSat-2

    NASA Astrophysics Data System (ADS)

    Nielsen, Karina; Villadsen, Heidi; Andersen, Ole; Stenseng, Lars; Knudsen, Per

    2015-04-01

    The high along track resolution of the SIRAL altimeter carried on-board CryoSat-2 offers a wide range of unique opportunities for satellite monitoring. This study focuses on the ability of CryoSat-2 to detect the effects of flood events such as increased river levels and inundation of land. Here we study two flood events; the Bangladesh flood event of June 2012 and the flooding in Thailand that lasted between July 2011 and January 2012. The flooding in these areas was caused by abnormal monsoonal rainfall and affected millions of people. We process CryoSat-2 level 1b SAR mode data to derive water levels for the areas and compare these levels before, during and after the flooding events. Other parameters such as the backscatter coefficient and pulse peakiness are also considered. To verify the extent of the flooding observed by CryoSat-2 we compare with independent sources such as Landsat images.

  14. Flight Technical Error Analysis of the SATS Higher Volume Operations Simulation and Flight Experiments

    NASA Technical Reports Server (NTRS)

    Williams, Daniel M.; Consiglio, Maria C.; Murdoch, Jennifer L.; Adams, Catherine H.

    2005-01-01

    This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.

  15. Extending Clause Learning of SAT Solvers with Boolean Gröbner Bases

    NASA Astrophysics Data System (ADS)

    Zengler, Christoph; Küchlin, Wolfgang

    We extend clause learning as performed by most modern SAT Solvers by integrating the computation of Boolean Gröbner bases into the conflict learning process. Instead of learning only one clause per conflict, we compute and learn additional binary clauses from a Gröbner basis of the current conflict. We used the Gröbner basis engine of the logic package Redlog contained in the computer algebra system Reduce to extend the SAT solver MiniSAT with Gröbner basis learning. Our approach shows a significant reduction of conflicts and a reduction of restarts and computation time on many hard problems from the SAT 2009 competition.

  16. Personality predictors of academic outcomes: big five correlates of GPA and SAT scores.

    PubMed

    Noftle, Erik E; Robins, Richard W

    2007-07-01

    The authors examined relations between the Big Five personality traits and academic outcomes, specifically SAT scores and grade-point average (GPA). Openness was the strongest predictor of SAT verbal scores, and Conscientiousness was the strongest predictor of both high school and college GPA. These relations replicated across 4 independent samples and across 4 different personality inventories. Further analyses showed that Conscientiousness predicted college GPA, even after controlling for high school GPA and SAT scores, and that the relation between Conscientiousness and college GPA was mediated, both concurrently and longitudinally, by increased academic effort and higher levels of perceived academic ability. The relation between Openness and SAT verbal scores was independent of academic achievement and was mediated, both concurrently and longitudinally, by perceived verbal intelligence. Together, these findings show that personality traits have independent and incremental effects on academic outcomes, even after controlling for traditional predictors of those outcomes. ((c) 2007 APA, all rights reserved). PMID:17605593

  17. CS2SAT: THE CONTROL SYSTEMS CYBER SECURITY SELF-ASSESSMENT TOOL

    SciTech Connect

    Kathleen A. Lee

    2008-01-01

    The Department of Homeland Security National Cyber Security Division has developed the Control System Cyber Security Self-Assessment Tool (CS2SAT) that provides users with a systematic and repeatable approach for assessing the cyber-security posture of their industrial control system networks. The CS2SAT was developed by cyber security experts from Department of Energy National Laboratories and with assistance from the National Institute of Standards and Technology. The CS2SAT is a desktop software tool that guides users through a step-by-step process to collect facility-specific control system information and then makes appropriate recommendations for improving the system’s cyber-security posture. The CS2SAT provides recommendations from a database of industry available cyber-security practices, which have been adapted specifically for application to industry control system networks and components. Each recommendation is linked to a set of actions that can be applied to remediate-specific security vulnerabilities.

  18. Subcutaneous adipose tissue topography (SAT-Top) development in children and young adults.

    PubMed

    Tafeit, Erwin; Möller, Reinhard; Jurimae, Toivo; Sudi, Karl; Wallner, Sandra Johanna

    2007-06-01

    The importance of body composition measurements to elucidate the dynamics of related diseases in pediatrics is gaining recognition. The methods used should not expose subjects to high doses of radiation and require substantial cooperation. The Lipometer is a new optical device that enables the non-invasive, quick and safe determination of the thickness of subcutaneous adipose tissue (SAT) layers (in mm) at any site of the human body. The topographic specification of 15 evenly distributed body sites, which makes it possible to precisely measure subcutaneous body fat distribution, is called subcutaneous adipose tissue topography (SAT-Top). SAT-Top was determined in more than 1000 children and young adults between the ages of 7 and 21. In this paper we describe the SAT-Top development of these subjects through different age groups and the differences between male and female SAT-Top development in each age group. SAT layer profiles (medians of the 15 body sites) for boys and girls in age group 1 (7-9 yrs) show a very similar pattern for both sexes, followed by slightly decreasing SAT layer thicknesses in boys and increasing values in girls in the subsequent age groups. Between age group 3 (11-13 yrs) and age group 7 (19-21 yrs) male and female SAT-Top is significantly different. The discriminating power between male and female SAT-Top was investigated by stepwise discriminant analysis, which provided no significant results for age group 1 (7-9 yrs), about 73% correct classification for age group 2 (9-11 yrs) and 3 (11-13 yrs), 83% for age group 4 (13-15 yrs), and about 91-93% for the following age groups (15-21 yrs). It is known that SAT development is the same in both sexes until puberty, when girls gain relatively more fat mass than boys to reach a higher body-fat percentage as adults. This paper presents a precise description of SAT development in boys and girls from childhood to adolescence, which provides a basis for further investigations. PMID:17847915

  19. SeaSat-A Satellite Scatterometer Mission Summary and Engineering Assessment Report

    NASA Technical Reports Server (NTRS)

    Johnson, J. W.; Lee, W. H.; Williams, L. A., Jr.

    1979-01-01

    The SeaSat-A satellite was launched on June 26, 1978 and operated in orbit through October 9, 1978. The SeaSat-A satellite scatterometer ocean surface wind field sensor began taking data on July 10, 1978 with virtually continuous operation for 95-1/2 days. A review of mission events significant to the scatterometer and a report on the hardware and software engineering assessment are presented.

  20. Study Pollution Impacts on Upper-Tropospheric Clouds with Aura, CloudSat, and CALIPSO Data

    NASA Technical Reports Server (NTRS)

    Wu, Dong

    2007-01-01

    This viewgraph presentation reviews the impact of pollution on clouds in the Upper Troposphere. Using the data from the Aura Microwave Limb Sounder (MLS), CloudSat, CALIPSO the presentation shows signatures of pollution impacts on clouds in the upper troposphere. The presentation demonstrates the complementary sensitivities of MLS , CloudSat and CALIPSO to upper tropospheric clouds. It also calls for careful analysis required to sort out microphysical changes from dynamical changes.

  1. Study of LEO-SAT microwave link for broad-band mobile satellite communication system

    NASA Technical Reports Server (NTRS)

    Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

    1993-01-01

    In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

  2. Abstract Model of the SATS Concept of Operations: Initial Results and Recommendations

    NASA Technical Reports Server (NTRS)

    Dowek, Gilles; Munoz, Cesar; Carreno, Victor A.

    2004-01-01

    An abstract mathematical model of the concept of operations for the Small Aircraft Transportation System (SATS) is presented. The Concept of Operations consist of several procedures that describe nominal operations for SATS, Several safety properties of the system are proven using formal techniques. The final goal of the verification effort is to show that under nominal operations, aircraft are safely separated. The abstract model was written and formally verified in the Prototype Verification System (PVS).

  3. Space Environment NanoSat Experiment (SENSE) - A New Frontier in Operational Space Environmental Monitoring (Invited)

    NASA Astrophysics Data System (ADS)

    Kalamaroff, K. I.; Thompson, D. C.; Cooke, D. L.; Gentile, L. C.; Bonito, N. A.; La Tour, P.; Sondecker, G.; Bishop, R. L.; Nicholas, A. C.; Doe, R. A.

    2013-12-01

    The Space Environmental NanoSat Experiment (SENSE) program is a rapid development effort of the USAF Space and Missiles Center Development Planning Directorate (SMC/XR) which will demonstrate the capability of NanoSats to perform space missions in an affordable and resilient manner. The three primary objectives for the SENSE mission are: 1) to develop best practices for operational CubeSat/NanoSat procurement, development, test, and operations; 2) to mature CubeSat bus and sensor component technology readiness levels; and 3) to demonstrate the operational utility of CubeSat measurements by flowing validated, low-latency data into operational space weather models. SENSE consists of two 3-U CubeSats built by Boeing Phantom Works. Both satellites are 3-axis stabilized with star cameras for attitude determination and are equipped with a Compact Total Electron Density Sensor (CTECS) to provide radio occultation measurements of total electron content and L-band scintillation. One satellite has a Cubesat Tiny Ionospheric Photometer (CTIP) monitoring 135.6 nm photons produced by the recombination of O+ ions and electrons. The other satellite has a Wind Ion Neutral Composite Suite (WINCS) to acquire simultaneous co-located, in situ measurements of atmospheric and ionospheric density, composition, temperature and winds/drifts. Mission data will be used to improve current and future space weather models and demonstrate the utility of data from CubeSats for operational weather requirements. Launch is scheduled for November 2013, and we will discuss the first 30 days of on-orbit operations.

  4. Integration of a MicroCAT Propulsion System and a PhoneSat Bus into a 1.5U CubeSat

    NASA Technical Reports Server (NTRS)

    Agasid, Elwood Floyd; Perez, Andres Dono; Gazulla, Oriol Tintore; Trinh, Greenfield Tran; Uribe, Eddie Anthony; Keidar, Michael; Haque, Samudra; Teel, George

    2014-01-01

    NASA Ames Research Center and the George Washington University have developed an electric propulsion subsystem that can be integrated into the PhoneSat bus. Experimental tests have shown a reliable performance by firing three different thrusters at various frequencies in vacuum conditions. The three thrusters were controlled by a SmartPhone that was running the PhoneSat software. The subsystem is fully operational and it requires low average power to function (about 0.1 W). The interface consists of a microcontroller that sends a trigger pulses to the PPU (Plasma Processing Unit), which is responsible for the thruster operation. Frequencies ranging from 1 to 50Hz have been tested, showing a strong flexibility. A SmartPhone acts as the main user interface for the selection of commands that control the entire system. The micro cathode arc thruster MicroCAT provides a high 1(sub sp) of 3000s that allows a 4kg satellite to obtain a (delta)V of 300m/s. The system mass is only 200g with a total of volume of 200(cu cm). The propellant is based on a solid cylinder made of Titanium, which is the cathode at the same time. This simplicity in the design avoids miniaturization and manufacturing problems. The characteristics of this thruster allow an array of MicroCATs to perform attitude control and orbital correcton maneuvers that will open the door for the implementation of an extensive collection of new mission concepts and space applications for CubeSats. NASA Ames is currently working on the integration of the system to fit the thrusters and PPU inside a 1.5U CubeSat together with the PhoneSat bus into a 1.5U CubeSat. This satellite is intended to be deployed from the ISS in 2015 and test the functionality of the thrusters by spinning the satellite around its long axis and measure the rotational speed with the phone byros. This test flight will raise the TRL of the propulsion system from 5 to 7 and will be a first test for further CubeSats with propulsion systems, a key

  5. Young SAT-Takers: Two Surveys. Survey I: Young SAT-Takers and Their Parents. Survey II: Test-Taking History for 1980-81 Young SAT-Takers. College Board Report No. 88-1.

    ERIC Educational Resources Information Center

    Wilder, Gita; And Others

    Two surveys were conducted to determine the impact of administration of the Scholastic Aptitude Test (SAT) to students under 14 years of age. Survey I provided data from 1,846 students tested in January 1984, and on their parents; there were 1,606 parent-student matches among respondents (i.e., student and parent questionnaires from the same…

  6. Scalability of the surface-based DNA algorithm for 3-SAT.

    PubMed

    Li, Dafa; Li, Xiangrong; Huang, Hongtao; Li, Xinxin

    2006-08-01

    Since Adleman first proposed DNA computing for the Hamiltonian path problem, several authors have reported DNA computing for 3-SAT. Previous research presented DNA computing on surfaces and demonstrated how to solve a four-variable four-clause instance of 3-SAT, and claimed that the surface-based approach was designed to scale up to larger problems. In this paper we establish an error model for the incomplete "mark" and imperfect "destroy" operations. By using the error model we argue that no matter how large the "mark" and "destroy" rates are we can always give satisfiable instances of 3-SAT such that no DNA strands remain on the surface at the end of the computation. By the surface-based approach the satisfiable instances of 3-SAT would be misdetermined to be unsatisfiable. Thus, the error leads to an incorrect result of the SAT computation. Furthermore, given the "mark" rate p and the "not-destroy" rate rho, we find that the approach can only solve at most N-variable instances of 3-SAT problems, where N=[(2+beta(2)+2+2 square root beta (2))/beta(2)] in which beta=1-1/(p+rhoq) and q=1-p and [a] is the greatest integer less than a or equal to a. PMID:16423447

  7. CubeSat-Associated Radiation Belt Research: Recent and Upcoming Observations

    NASA Astrophysics Data System (ADS)

    Blum, Lauren; Li, Xinlin; Schiller, Quintin

    2016-07-01

    Interest in CubeSats has grown dramatically in the past decade within the space physics community. While CubeSats are generally accepted now to be useful tools for education and technology development/demonstration, their ability to provide scientific value is often still questioned. Radiation belt physics, however, is one area in which the scientific utility of these small platforms has been demonstrated and continues to offer great promise. The Colorado Student Space Weather Experiment (CSSWE) CubeSat, designed, built, tested, and operated by students at University of Colorado with mentoring from LASP professionals, was one of the first of now a long line of CubeSats designed to study radiation belt dynamics. Launched in September 2012, just a few weeks after NASA's Van Allen Probes, CSSWE provided valuable measurements of energetic electrons and protons from low-Earth orbit for two years, well beyond its nominal 3-month mission lifetime. The status of and results from CSSWE will be presented, with an emphasis on how these measurements have been combined with those from balloons and larger satellite missions to better understand radiation belt electron acceleration and loss processes. Some highlights from other radiation belt-related CubeSats will also be presented, along with upcoming missions. Radiation belt studies are a prime example of how small inexpensive CubeSats can be used to provide valuable scientific measurements and complement larger missions.

  8. Comparisons of Satellite-Deduced Overlapping Cloud Properties and CALIPSO CloudSat Data

    NASA Technical Reports Server (NTRS)

    Chang, Fu-Lung; Minnis, Patrick; Lin, Bing; Sun-Mack, Sunny

    2010-01-01

    Introduction to the overlapped cloud properties derived from polar-orbiting (MODIS) and geostationary (GOES-12, -13, Meteosat-8, -9, etc.) meteorological satellites, which are produced at the NASA Langley Research Center (LaRC) cloud research & development team (NASA lead scientist: Dr. Patrick Minnis). Comparison of the LaRC CERES MODIS Edition-3 overlapped cloud properties to the CALIPSO and the CloudSat active sensing data. High clouds and overlapped clouds occur frequently as deduced by CALIPSO (44 & 25%), CloudSat (25 & 4%), and MODIS (37 & 6%). Large fractions of optically-thin cirrus and overlapped clouds are deduced from CALIPSO, but much smaller fractions are from CloudSat and MODIS. For overlapped clouds, the averaged upper-layer CTHs are about 12.8 (CALIPSO), 10.9 (CloudSat) and 10 km (MODIS), and the averaged lower-layer CTHs are about 3.6 (CALIPSO), 3.2 (CloudSat) and 3.9 km (MODIS). Based on comparisons of upper and lower-layer cloud properties as deduced from the MODIS, CALIPSO and CloudSat data, more enhanced passive satellite methods for retrieving thin cirrus and overlapped cloud properties are needed and are under development.

  9. Using Additive Manufacturing to Print a CubeSat Propulsion System

    NASA Technical Reports Server (NTRS)

    Marshall, William M.

    2015-01-01

    CubeSats are increasingly being utilized for missions traditionally ascribed to larger satellites CubeSat unit (1U) defined as 10 cm x 10 cm x 11 cm. Have been built up to 6U sizes. CubeSats are typically built up from commercially available off-the-shelf components, but have limited capabilities. By using additive manufacturing, mission specific capabilities (such as propulsion), can be built into a system. This effort is part of STMD Small Satellite program Printing the Complete CubeSat. Interest in propulsion concepts for CubeSats is rapidly gaining interest-Numerous concepts exist for CubeSat scale propulsion concepts. The focus of this effort is how to incorporate into structure using additive manufacturing. End-use of propulsion system dictates which type of system to develop-Pulse-mode RCS would require different system than a delta-V orbital maneuvering system. Team chose an RCS system based on available propulsion systems and feasibility of printing using a materials extrusion process. Initially investigated a cold-gas propulsion system for RCS applications-Materials extrusion process did not permit adequate sealing of part to make this a functional approach.

  10. Characterization of spacecraft and environmental disturbances on a SmallSat

    NASA Technical Reports Server (NTRS)

    Johnson, Thomas A.; Nguyen, Dung Phu Chi; Cuda, Vince; Freesland, Doug

    1994-01-01

    The objective of this study is to model the on-orbit vibration environment encountered by a SmallSat. Vibration control issues are common to the Earth observing, imaging, and microgravity communities. A spacecraft may contain dozens of support systems and instruments each a potential source of vibration. The quality of payload data depends on constraining vibration so that parasitic disturbances do not affect the payload's pointing or microgravity requirement. In practice, payloads are designed incorporating existing flight hardware in many cases with nonspecific vibration performance. Thus, for the development of a payload, designers require a thorough knowledge of existing mechanical devices and their associated disturbance levels. This study evaluates a SmallSat mission and seeks to answer basic questions concerning on-orbit vibration. Payloads were considered from the Earth observing, microgravity, and imaging communities. Candidate payload requirements were matched to spacecraft bus resources of present day SmallSats. From the set of candidate payloads, the representative payload GLAS (Geoscience Laser Altimeter System) was selected. The requirements of GLAS were considered very stringent for the 150 - 500 kg class of payloads. Once the payload was selected, a generic SmallSat was designed in order to accommodate the payload requirements (weight, size, power, etc.). This study seeks to characterize the on-orbit vibration environment of a SmallSat designed for this type of mission and to determine whether a SmallSat can provide the precision pointing and jitter control required for earth observing payloads.

  11. Preliminary Characterization Results from the DebriSat Project

    NASA Technical Reports Server (NTRS)

    Rivero, M.; Shiotani, B.; Kleespies, J.; Toledo-Burdett, R.; Moraguez, M.; Carrasquila, M.; Fitz-Coy, N.; Liou, J.-C.; Sorge, M.; Huynh, T.

    2016-01-01

    The DebriSat project is a continuing effort sponsored by NASA and DoD to update existing break-up models using data obtained from two separate hypervelocity impact tests used to simulate on-orbit collisions. To protect the fragments resulting from the impact tests, "soft-catch" arenas made of polyurethane foam panels were utilized. After each impact test, the test chamber was cleaned and debris resulting from the catastrophic demise of the test article were collected and shipped to the University of Florida for post-impact processing. The post-impact processing activities include collecting, characterizing, and cataloging of the fragments. Since the impact tests, a team of students has been working to characterize the fragments in terms of their mass, size, shape, color and material content. The focus of the 20 months since the impact tests has been on the collection of 2 millimeters- and larger fragments resulting from impact test on the 56 kilogram-representative LEO (Low Earth Orbit) satellite referred to as DebriSat. To date we have recovered in excess of 115,000 fragments, 30,000 more than the prediction of 85,000 fragments from the existing model. We continue to collect fragments but have transitioned to the characterization phase of the post-impact activities. Since the start of the characterization phase, the focus has been to utilize automation to (i) expedite fragment characterization process and (ii) minimize human-in-the- loop. We have developed and implemented such automated processes; e.g., we have automated the data entry process to reduce operator errors during transcription of the measurement data. However, at all steps of the process, there is human oversight to ensure the integrity of the data. Additionally, we have developed and implemented repeatability and reproducibility tests to ensure that the instrumentation used in the characterization process is accurate and properly calibrated. In this paper, the implemented processes are described and

  12. In female rats, ethylene glycol treatment elevates protein expression of hepatic and renal oxalate transporter sat-1 (Slc26a1) without inducing hyperoxaluria

    PubMed Central

    Breljak, Davorka; Brzica, Hrvoje; Vrhovac, Ivana; Micek, Vedran; Karaica, Dean; Ljubojević, Marija; Sekovanić, Ankica; Jurasović, Jasna; Rašić, Dubravka; Peraica, Maja; Lovrić, Mila; Schnedler, Nina; Henjakovic, Maja; Wegner, Waja; Burckhardt, Gerhard; Burckhardt, Birgitta C.; Sabolić, Ivan

    2015-01-01

    Aim To investigate whether the sex-dependent expression of hepatic and renal oxalate transporter sat-1 (Slc26a1) changes in a rat model of ethylene glycol (EG)-induced hyperoxaluria. Methods Rats were given tap water (12 males and 12 females; controls) or EG (12 males and 12 females; 0.75% v/v in tap water) for one month. Oxaluric state was confirmed by biochemical parameters in blood plasma, urine, and tissues. Expression of sat-1 and rate-limiting enzymes of oxalate synthesis, alcohol dehydrogenase 1 (Adh1) and hydroxy-acid oxidase 1 (Hao1), was determined by immunocytochemistry (protein) and/or real time reverse transcription polymerase chain reaction (mRNA). Results EG-treated males had significantly higher (in μmol/L; mean ± standard deviation) plasma (59.7 ± 27.2 vs 12.9 ± 4.1, P < 0.001) and urine (3716 ± 1726 vs 241 ± 204, P < 0.001) oxalate levels, and more abundant oxalate crystaluria than controls, while the liver and kidney sat-1 protein and mRNA expression did not differ significantly between these groups. EG-treated females, in comparison with controls had significantly higher (in μmol/L) serum oxalate levels (18.8 ± 2.9 vs 11.6 ± 4.9, P < 0.001), unchanged urine oxalate levels, low oxalate crystaluria, and significantly higher expression (in relative fluorescence units) of the liver (1.59 ± 0.61 vs 0.56 ± 0.39, P = 0.006) and kidney (1.77 ± 0.42 vs 0.69 ± 0.27, P < 0.001) sat-1 protein, but not mRNA. The mRNA expression of Adh1 was female-dominant and that of Hao1 male-dominant, but both were unaffected by EG treatment. Conclusions An increased expression of hepatic and renal oxalate transporting protein sat-1 in EG-treated female rats could protect from hyperoxaluria and oxalate urolithiasis. PMID:26526882

  13. LifeSat engineering in-house vehicle design

    NASA Technical Reports Server (NTRS)

    Adkins, A.; Badhwar, G.; Bryant, L.; Caram, J.; Conley, G.; Crull, T.; Cuthbert, P.; Darcy, E.; Delaune, P.; Edeen, M.

    1992-01-01

    The LifeSat program was initiated to research the effects of microgravity and cosmic radiation on living organisms. The effects of long-term human exposure to free-space radiation fields over a range of gravitational environments has long been recognized as one of the primary design uncertainties for human space exploration. A critical design issue in the radiation biology requirements was the lack of definition of the minimum radiation absorbed dosage required to produce statistically meaningful data. The Phase A study produced a spacecraft conceptual design resembling a Discoverer configuration with a total weight of approximately 2800 pounds that would carry a 525-pound payload module (45 inches in diameter and 36 inches long) and support up to 12 rodents and a general biology module supporting lower life forms for an on-orbit duration of up to 60 days. The phase B conceptual designs focused on gravitational biology requirements and only briefly addressed the design impacts of the shift toward radiobiological science that occurred during the latter half of the Phase B studies.

  14. Satisfiability Threshold for Random Regular nae-sat

    NASA Astrophysics Data System (ADS)

    Ding, Jian; Sly, Allan; Sun, Nike

    2016-01-01

    We consider the random regular k- nae- sat problem with n variables, each appearing in exactly d clauses. For all k exceeding an absolute constant {{k}_0}, we establish explicitly the satisfiability threshold {{{d_star} equiv {d_star(k)}}}. We prove that for {{d < d_star}} the problem is satisfiable with high probability, while for {{d > d_star}} the problem is unsatisfiable with high probability. If the threshold {{d_star}} lands exactly on an integer, we show that the problem is satisfiable with probability bounded away from both zero and one. This is the first result to locate the exact satisfiability threshold in a random constraint satisfaction problem exhibiting the condensation phenomenon identified by Krzakała et al. [Proc Natl Acad Sci 104(25):10318-10323, 2007]. Our proof verifies the one-step replica symmetry breaking formalism for this model. We expect our methods to be applicable to a broad range of random constraint satisfaction problems and combinatorial problems on random graphs.

  15. CryoSat-2 commissioning phase results summary

    NASA Astrophysics Data System (ADS)

    Cullen, R.

    2010-12-01

    CryoSat-2 was launched on 8th April 2010 and following a 3 day LEOP entered its 6 month commissioning phase. The primary payload of the platform consists of the Synthetic Interferometric Radar Altimeter (SIRAL-2) with support for its data processing coming from data acquired from on-board DORIS DGXX and star trackers. We present a description of the payload and provide post-launch performance summaries in terms of SIRAL internal/external calibration in combination with an assessment of global data acquisition achievement in each of the three science modes: Low resolution pulse-width limited mode (LRM) over interior land-ice and ocean to support POD, Synthetic aperture radar mode (SARM) for sea-ice and SAR interferometric mode (SARInM) for higher surface slope land-ice sheet margin acquisitions. Commissioning activities are summarised with examples and we provide conclusions on the experiences gained with the data during this period. Specific issues are highlighted and that Users of the data products should consider taking into account with their analyses. Finally, present performances of the three science modes over transponders and open ocean calibration zones are provided in addition to specific cases over land and sea ice. Preliminary performances of DORIS and star trackers will be provided in the context of overall SIRAL performance.

  16. NMR implementation of adiabatic SAT algorithm using strongly modulated pulses.

    PubMed

    Mitra, Avik; Mahesh, T S; Kumar, Anil

    2008-03-28

    NMR implementation of adiabatic algorithms face severe problems in homonuclear spin systems since the qubit selective pulses are long and during this period, evolution under the Hamiltonian and decoherence cause errors. The decoherence destroys the answer as it causes the final state to evolve to mixed state and in homonuclear systems, evolution under the internal Hamiltonian causes phase errors preventing the initial state to converge to the solution state. The resolution of these issues is necessary before one can proceed to implement an adiabatic algorithm in a large system where homonuclear coupled spins will become a necessity. In the present work, we demonstrate that by using "strongly modulated pulses" (SMPs) for the creation of interpolating Hamiltonian, one can circumvent both the problems and successfully implement the adiabatic SAT algorithm in a homonuclear three qubit system. This work also demonstrates that the SMPs tremendously reduce the time taken for the implementation of the algorithm, can overcome problems associated with decoherence, and will be the modality in future implementation of quantum information processing by NMR. PMID:18376911

  17. On the behaviour of random K-SAT on trees

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, Supriya; Sumedha

    2012-05-01

    We consider the K-satisfiability problem on a regular d-ary rooted tree. For this model, we demonstrate how we can calculate in closed form the moments of the total number of solutions as a function of d and K, where the average is over all realizations for a fixed assignment of the surface variables. We find that different moments pick out different 'critical' values of d, below which they diverge as the total number of variables on the tree \\rightarrow \\infty and above which they decay. We show that K-SAT on the random graph also behaves similarly. We also calculate exactly the fraction of instances that have solutions for all K. On the tree, this quantity decays to 0 (as the number of variables increases) for any d > 1. However, the recursion relations for this quantity have a non-trivial fixed point solution which indicates the existence of a different transition in the interior of an infinite rooted tree.

  18. Bounded Semantics of CTL and SAT-Based Verification

    NASA Astrophysics Data System (ADS)

    Zhang, Wenhui

    Bounded model checking has been proposed as a complementary approach to BDD based symbolic model checking for combating the state explosion problem, esp. for efficient error detection. This has led to a lot of successful work with respect to error detection in the checking of LTL, ACTL (the universal fragment of CTL) and ACTL* properties by satisfiability testing. The use of bounded model checking for verification (in contrast to error detection) of LTL and ACTL properties has later also been studied. This paper studies the potentials and limitations of bounded model checking for the verification of CTL and CTL* formulas. On the theoretical side, we first provide a framework for discussion of bounded semantics, which serves as the basis for bounded model checking, then extend the bounded semantics of ACTL to a bounded semantics of CTL, and discuss the limitation of developing such a bounded semantics for CTL*. On the practical side, a deduction of a SAT-based bounded model checking approach for ACTL properties from the bounded semantics of CTL is demonstrated, and a comparison of such an approach with BDD-based model checking is presented based on experimental results.

  19. NMR implementation of adiabatic SAT algorithm using strongly modulated pulses

    NASA Astrophysics Data System (ADS)

    Mitra, Avik; Mahesh, T. S.; Kumar, Anil

    2008-03-01

    NMR implementation of adiabatic algorithms face severe problems in homonuclear spin systems since the qubit selective pulses are long and during this period, evolution under the Hamiltonian and decoherence cause errors. The decoherence destroys the answer as it causes the final state to evolve to mixed state and in homonuclear systems, evolution under the internal Hamiltonian causes phase errors preventing the initial state to converge to the solution state. The resolution of these issues is necessary before one can proceed to implement an adiabatic algorithm in a large system where homonuclear coupled spins will become a necessity. In the present work, we demonstrate that by using "strongly modulated pulses" (SMPs) for the creation of interpolating Hamiltonian, one can circumvent both the problems and successfully implement the adiabatic SAT algorithm in a homonuclear three qubit system. This work also demonstrates that the SMPs tremendously reduce the time taken for the implementation of the algorithm, can overcome problems associated with decoherence, and will be the modality in future implementation of quantum information processing by NMR.

  20. CicArMiSatDB: the chickpea microsatellite database

    PubMed Central

    2014-01-01

    Background Chickpea (Cicer arietinum) is a widely grown legume crop in tropical, sub-tropical and temperate regions. Molecular breeding approaches seem to be essential for enhancing crop productivity in chickpea. Until recently, limited numbers of molecular markers were available in the case of chickpea for use in molecular breeding. However, the recent advances in genomics facilitated the development of large scale markers especially SSRs (simple sequence repeats), the markers of choice in any breeding program. Availability of genome sequence very recently opens new avenues for accelerating molecular breeding approaches for chickpea improvement. Description In order to assist genetic studies and breeding applications, we have developed a user friendly relational database named the Chickpea Microsatellite Database (CicArMiSatDB http://cicarmisatdb.icrisat.org). This database provides detailed information on SSRs along with their features in the genome. SSRs have been classified and made accessible through an easy-to-use web interface. Conclusions This database is expected to help chickpea community in particular and legume community in general, to select SSRs of particular type or from a specific region in the genome to advance both basic genomics research as well as applied aspects of crop improvement. PMID:24952649

  1. Ad hoc CubeSat constellations: Secondary launch coverage and distribution

    NASA Astrophysics Data System (ADS)

    Marinan, A.; Nicholas, A.; Cahoy, K.

    The primary purpose of a constellation is to obtain global measurements with improved spatial and temporal resolution. The small size, low cost, standardized form factor, and increasing availability of commercial parts for CubeSats make them ideal for use in constellations. However, without taking advantage of secondary payload opportunities, it would be costly to launch and distribute a CubeSat constellation into a specific configuration. A cost-effective way to launch a constellation of CubeSats is via consecutive secondary payload launch opportunities, but the resulting constellation would be an ad hoc mix of orbit parameters. We focus on the feasibility of cobbling together constellation-like functionality from multiple secondary payload opportunities. Each participating CubeSat (or set of CubeSats) per launch could have completely different orbital parameters, even without propulsion onboard the CubeSats or intermediate transfer carriers. We look at the ground coverages that could be obtained for a constellation of five to six orbital planes with one to six satellites in each plane. We analyze past and announced future launch opportunities for CubeSats, including launch platforms supported by the NASA Educational Launch of Nanosatellites (ELaNa). We consider combinations of possible launch locations and temporal spacings over the course of one year and simulate the resulting ground coverage patterns and revisit times for an ad hoc constellation using these launch opportunities. We perform this analysis for two separate case studies - one with only US launches and one with both US and non-US opportunities - and vary the number of satellites per orbital plane. Typical CubeSat mission lifetimes and deorbit times for low-altitude orbits are included in these analyses. The ad hoc constellation results are compared to coverage from uniformly-placed LEO constellations and are quantified in terms of revisit time, time to 100% global coverage, and response time. For mu

  2. Ten-Year Trends in SAT Scores and Other Characteristics of High School Seniors Taking the SAT and Planning To Study Mathematics, Science, or Engineering. Research Report.

    ERIC Educational Resources Information Center

    Grandy, Jerilee

    This study analyzed data from the Scholastic Aptitude Test (SAT) taken by high school seniors between 1975 and 1986. Its purpose was to study trends in the numbers, test scores, and other characteristics of examinees planning to major in mathematics, science, and engineering, and to compare these data with comparable data from examinees planning…

  3. Evaluation of SAT-1, SAT-2 and GalNAcT-1 mRNA in colon cancer by real-time PCR.

    PubMed

    Gornati, Rosalba; Chini, Valentina; Rimoldi, Simona; Meregalli, Maurizio; Schiaffino, Eugenio; Bernardini, Giovanni

    2007-04-01

    By qualitative and quantitative PCR, we evaluated the expression of three messengers coding for SAT-1, SAT-2 and GalNAcT-1 in human samples of intestinal cancer and some cell lines (breast cancer and melanomas). Qualitative PCR demonstrated, in human tissues but not in the cell lines examined, the presence of an mRNA that lacks hexon 3; experiments performed on transfected SKMEL-28 excluded a regulative role of this noncanonical mRNA. Data from real-time PCR, statistically analysed by ANOVA indicated that the mRNA expression of all the considered glycosyltransferases (SAT-1, SAT-2 and GalNAcT-1) was significantly different in tumours versus their own control. The ganglioside patterns in the examined samples did not correlate with mRNA expression; this finding demonstrates that ganglioside expression is the result of a very complex balance between anabolic and catabolic enzyme activities. Although this study is still preliminary, it opens a new possibility for neoplastic prognosis finding potential molecular markers among the mRNAs that codify for glycosyltransferases. PMID:17119850

  4. The Social Attribution Task-Multiple Choice (SAT-MC): A Psychometric and Equivalence Study of an Alternate Form.

    PubMed

    Johannesen, Jason K; Lurie, Jessica B; Fiszdon, Joanna M; Bell, Morris D

    2013-01-01

    The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of "Theory of Mind," the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials. PMID:23864984

  5. The Social Attribution Task-Multiple Choice (SAT-MC): A Psychometric and Equivalence Study of an Alternate Form

    PubMed Central

    Johannesen, Jason K.; Lurie, Jessica B.; Fiszdon, Joanna M.; Bell, Morris D.

    2013-01-01

    The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of “Theory of Mind,” the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials. PMID:23864984

  6. Assessing the format of the presentation of text in developing a Reading Strategy Assessment Tool (R-SAT).

    PubMed

    Gilliam, Sara; Magliano, Joseph P; Millis, Keith K; Levinstein, Irwin; Boonthum, Chutima

    2007-05-01

    We are constructing a new computerized test of reading comprehension called the Reading Strategy Assessment Tool (R-SAT). R-SAT elicits and analyzes verbal protocols that readers generate in response to questions as they read texts. We examined whether the amount of information available to the reader when reading and answering questions influenced the extent to which R-SAT accounts for comprehension. We found that R-SAT was most predictive of comprehension when the readers did not have access to the text as they answered questions. PMID:17695345

  7. Investigating the Efficacy of CubeSats for Asteroid Detection

    NASA Technical Reports Server (NTRS)

    O'Toole, Conor

    2015-01-01

    A simulation to examine the potential of a network of CubeSats for detecting Near Earth Objects is discussed, in terms of goals, methods used and initial results obtained. By designing a basic optical system and the orbital parameters of the satellites in this network, their effectiveness for detecting asteroids is examined, with a small sample of cataloged asteroids considered.The conditions to be satisfied for detection cover both the geometrical aspects of astronomy such as field of view and line of sight, along with more technical optics-based conditions such as resolution and sensitivity of our telescopes. Of special interest to us in this work is the region of the sky between 45 deg. and 90 deg. from the Sun, as seen from the Earth. This part of the sky is currently unobservable by ground-based surveys and so provides the primary reason to consider a space-based one. There exist a number of issues with the simulation which call these results into question, but an eort has been made to remove those results which exceed the possible capabilities of the satellite network, and identify those aspects of the mission which should be examined in order to provide an in-depth assessment of it's performance. With these filters applied to the overall data, a tentative result of 1458 total detections over an 85 year period has been obtained, with 14 of the 22 asteroids in the sample being detected at least once. A number of ways in which the simulation could be improved are also proposed, both in-terms of addressing the aforementioned issues, as well as how to improve on the accuracy of the simulation and capture as many aspects of a space-based optical astronomy mission as possible,with the possible nal form of the simulation being a tool for assessing the performance of any space-based optical mission to detect asteroids.

  8. Progress towards a Drag-free SmallSat

    NASA Astrophysics Data System (ADS)

    Saraf, Shailendhar

    The net force acting on a drag-free satellite is purely gravitational as all other forces, mainly atmospheric drag and solar radiation pressure, are canceled out. In order to achieve this, a free floating reference (test mass) inside the satellite is shielded against all forces but gravity and a system of thrusters is commanded by a control algorithm such that the relative displacement between the reference and the satellite stays constant. The main input to that control algorithm is the output of a sensor which measures the relative displacement between the satellite and the test mass. Internal disturbance forces such as electrostatic or magnetic forces cannot be canceled out his way and have to be minimized by a careful design of the satellite. A drag-free technology package is under development at Stanford since 2004. It includes an optical displacement sensor to measure the relative position of the test mass inside the satellite, a caging mechanism to lock the test mass during launch, a UV LED based charge management system to minimize the effect of electrostatic forces, a thermal enclosure, and the drag-free control algorithms. Possible applications of drag-free satellites in fundamental physics (Gravity Probe B, LISA), geodesy (GOCE), and navigation (TRIAD I). In this presentation we will highlight the progress of the technology development towards a drag-free mission. The planned mission on a SaudiSat bus will demonstrate drag-free technology on a small spacecraft at a fraction of the cost of previous drag-free missions. The target acceleration noise is 10-12 m/sec2. With multiple such satellites a GRACE-like mission with improved sensitivity and potentially improved spatial and temporal resolution can be achieved.

  9. Evaluation of WindSat Land Surface Data over West Africa

    NASA Astrophysics Data System (ADS)

    Steele-Dunne, S. C.; Li, L.; Gaiser, P.; van de Giesen, N.

    2009-12-01

    The WindSat instrument is a spaceborne polarimetric microwave radiometer, data from which has been used in a wide range of ocean and land-based applications. Li et al. (2009) developed a physically based algorithm, based on maximum likelihood estimation, which uses vertical and horizontal polarization data at 10, 18.7 and 37 GHz to simultaneously retrieve soil moisture, vegetation water content and land surface temperature. In this research, the performance of these Windsat land products is evaluated over West Africa, from February 2003 to May 2006, through comparison with both in-situ and remote-sensing data. Though the in-situ data and WindSat soil moisture produce showed the same general temporal pattern, it is important to note that the in-situ observations were collected at a single point while the WindSat soil moisture is a 25km gridded product. For a more complete view, WindSat soil moisture and vegetation water content products were also analyzed alongside precipitation data (TRMM), vegetation indices (e.g. NDVI) and other soil moisture products (e.g. ERS) from remote-sensing to determine how well the WindSat data could capture the soil moisture and vegetation response to observed precipitation. Our analysis shows that WindSat clearly detects the north-south gradient in soil moisture due to the West African monsoon. The difference in regime between tropical forest, savanna and desert is plainly discernible in both the soil moisture and vegetation water content data. The soil moisture dynamics of the Niger Inland Delta can also be seen in the WindSat data. The modest impact of local rainfall is seen during the rainy season, while a significant rise in soil moisture is detected in October when rainfall from the Niger and Bani headwaters reaches the inland delta. The main growing season follows, and the soil moisture is seen to decrease slowly due to infiltration and evapotranspiration. These results support those of the global WindSat validation, and

  10. Integrated monitoring technologies for the management of a Soil-Aquifer-Treatment (SAT) system

    NASA Astrophysics Data System (ADS)

    Kallioras, Andreas; Kofakis, Petros; Bumberger, Jan; Athanasiou, Georgios; Schimdt, Felix; Apostolopoulos, Georgios; Uzunoglou, Nikolaos; Dietrich, Peter; Schuth, Christoph

    2015-04-01

    Artificial recharge of groundwater has an important role to play in water reuse as treated wastewater effluent can be infiltrated into the ground for aquifer recharge. As the effluent moves through the soil and the aquifer, it undergoes significant quality improvements through physical, chemical, and biological processes in the underground environment. Collectively, these processes and the water quality improvement obtained are called soil-aquifer-treatment (SAT) or geopurification. The pilot site of Lavrion Technological & Cultural Park (LTCP) of the National Technical University of Athens (NTUA), involves the employment of plot infiltration basins at experimental scale, which will be using waters of impaired quality as a recharge source, and hence acting as a Soil-Aquifer-Treatment, SAT, system. Τhe LTCP site will be employed as a pilot SAT system complemented by new technological developments, which will be providing continuous monitoring of the quantitative and qualitative characteristics of infiltrating groundwater through all hydrologic zones (i.e. surface, unsaturated and saturated zone). This will be achieved by the development and installation of an integrated system of prototype sensing technologies, installed on-site, and offering a continuous evaluation of the performance of the SAT system. An integrated approach of the performance evaluation of any operating SAT system should aim at parallel monitoring of all hydrologic zones, proving the sustainability of all involved water quality treatment processes within unsaturated and saturated zone. Hence a prototype system of Time and Frequency Domain Reflectometry (TDR & FDR) sensors is developed and will be installed, in order to achieve continuous quantitative monitoring of the unsaturated zone through the entire soil column down to significant depths below the SAT basin. Additionally, the system contains two different radar-based sensing systems that will be offering (i) identification of preferential

  11. CubeSat mission design based on a systems engineering approach

    NASA Astrophysics Data System (ADS)

    Asundi, S. A.; Fitz-Coy, N. G.

    With the exception of the CubeSat specification, CubeSat design and development approaches have been mostly ad hoc, which has questioned their reliability. A systems engineering approach, based on the guidelines of NASA's Systems Engineering Handbook has been developed for CubeSats to facilitate systematic design, development and address their reliability, traceability, and reusability. The CubeSat systems engineering approach, developed as a repeatable process, uses a top-down design methodology to translate mission definitions into basic building blocks, components, interfaces and tasks, that then facilitate a bottom-up development and fabrication process. Some of the design tools (e.g., N2 diagram) described in NASAs Systems Engineering Handbook are utilized early in the design phase to identify potential conflicts in the mechanical and electrical interfaces. A novel subsystem level flowdown, which transcribes the system level requirements into identifiable CubeSat subsystems, (i.e., building blocks) is described. Utilizing this approach yields full traceability from mission concept to subsystem component to flight software. Additionally, the approach facilitates the estimation of the mission overhead in terms of power, telemetry, and computation associated with each component, interface, and task.

  12. PlumeSat: A Micro-Satellite Based Plume Imagery Collection Experiment

    SciTech Connect

    Ledebuhr, A.G.; Ng, L.C.

    2002-06-30

    This paper describes a technical approach to cost-effectively collect plume imagery of boosting targets using a novel micro-satellite based platform operating in low earth orbit (LEO). The plume collection Micro-satellite or PlueSat for short, will be capable of carrying an array of multi-spectral (UV through LWIR) passive and active (Imaging LADAR) sensors and maneuvering with a lateral divert propulsion system to different observation altitudes (100 to 300 km) and different closing geometries to achieve a range of aspect angles (15 to 60 degrees) in order to simulate a variety of boost phase intercept missions. The PlumeSat will be a cost effective platform to collect boost phase plume imagery from within 1 to 10 km ranges, resulting in 0.1 to 1 meter resolution imagery of a variety of potential target missiles with a goal of demonstrating reliable plume-to-hardbody handover algorithms for future boost phase intercept missions. Once deployed on orbit, the PlumeSat would perform a series phenomenology collection experiments until expends its on-board propellants. The baseline PlumeSat concept is sized to provide from 5 to 7 separate fly by data collects of boosting targets. The total number of data collects will depend on the orbital basing altitude and the accuracy in delivering the boosting target vehicle to the nominal PlumeSat fly-by volume.

  13. Urano y sus dos satélites irregulares recientemente descubiertos

    NASA Astrophysics Data System (ADS)

    Parisi, M. G.; Brunini, A.

    Hasta hace poco tiempo, Urano era el único de los Planetas Gigantes que no poseía satélites irregulares. Esto lo diferenciaba del resto de los planetas Gigantes, al igual que la peculiar oblicuidad de su eje de spin. La gran inclinación de su eje de rotación se debe probablemente a una colisión que sufrió el planeta con otro embrión planetario al final del proceso de formación. Esta colisión habría desligado satélites exteriores preexistentes del planeta. Recientemente se han descubierto dos satélites irregulares de Urano, lo que introduce algunas nuevas cotas y condiciones en el escenario de la "Hipótesis de la Gran Colisión" . Los satélites irregulares de Urano tuvieron que ser capturados en una etapa posterior a la del escenario de la Gran Colisión, de no ser así, hubieran sido eyectados del sistema por el impulso impartido con ese gran impacto. En este trabajo, se discuten los posibles mecanismos de captura de los satélites irregulares y se presenta un nuevo posible mecanismo para dicha captura.

  14. The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.

    2005-01-01

    This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.

  15. General Aviation in Nebraska: Nebraska SATS Project Background Paper No. 1

    NASA Technical Reports Server (NTRS)

    Smith, Russell; Wachal, Jocelyn

    2000-01-01

    The Nebraska SATS project is a state-level component of NASA's Small Aircraft Transportation System (SATS). During the next several years the project will examine several different factors affecting SATS implementation in Nebraska. These include economic and taxation issues, public policy issues, airport planning processes, information dissemination strategies, and systemic change factors. This background paper profiles the general aviation system in Nebraska. It is written to provide information about the "context" within which SATS will be pursued. The primary focus is thus on describing and providing background information about the current situation. A secondary focus is on drawing general conclusions about the ability of the current system to incorporate the types of changes implied by SATS. First, some brief information on the U.S. aviation system is provided. The next two sections profile the current general aviation aircraft and pilot base. Nebraska's system of general aviation airports is then described. Within this section of the paper, information is provided on the different types of general aviation airports in Nebraska, airport activity levels and current infrastructure. The fourth major section of the background paper looks at Nebraska's local airport authorities. These special purpose local governments oversee the majority of the general aviation airports in the state. Among the items examined are total expenditures, capital expenditures and planning activities. Next, the paper provides background information on the Nebraska Department of Aeronautics (NDA) and recent Federal funding for general aviation in Nebraska. The final section presents summary conclusions.

  16. SAT, a flexible and optimized Web application for SSR marker development

    PubMed Central

    Dereeper, Alexis; Argout, Xavier; Billot, Claire; Rami, Jean-François; Ruiz, Manuel

    2007-01-01

    Background Simple Sequence Repeats (SSRs), or microsatellites, are among the most powerful genetic markers known. A common method for the development of SSR markers is the construction of genomic DNA libraries enriched for SSR sequences, followed by DNA sequencing. However, designing optimal SSR markers from bulk sequence data is a laborious and time-consuming process. Results SAT (SSR Analysis Tool) is a user-friendly Web application developed to minimize tedious manual operations and reduce errors. This tool facilitates the integration, analysis and display of sequence data from SSR-enriched libraries. SAT is designed to successively perform base calling and quality evaluation of chromatograms, eliminate cloning vector, adaptors and low quality sequences, detect chimera or partially digested sequences, search for SSR motifs, cluster and assemble the redundant sequences, and design SSR primer pairs. An additional virtual PCR step establishes primer specificity. Users may modify the different parameters of each step of the SAT analysis. Although certain steps are compulsory, such as SSR motifs search and sequence assembly, users do not have to run the entire pipeline, and they can choose selectively which steps to perform. A database allows users to store and query results, and to redo individual steps of the workflow. Conclusion The SAT Web application is available at , and a standalone command-line version is also freely downloadable. Users must send an email to the SAT administrator tropgene@cirad.fr to request a login and password. PMID:18047663

  17. CubeSat mission design software tool for risk estimating relationships

    NASA Astrophysics Data System (ADS)

    Gamble, Katharine Brumbaugh; Lightsey, E. Glenn

    2014-09-01

    In an effort to make the CubeSat risk estimation and management process more scientific, a software tool has been created that enables mission designers to estimate mission risks. CubeSat mission designers are able to input mission characteristics, such as form factor, mass, development cycle, and launch information, in order to determine the mission risk root causes which historically present the highest risk for their mission. Historical data was collected from the CubeSat community and analyzed to provide a statistical background to characterize these Risk Estimating Relationships (RERs). This paper develops and validates the mathematical model based on the same cost estimating relationship methodology used by the Unmanned Spacecraft Cost Model (USCM) and the Small Satellite Cost Model (SSCM). The RER development uses general error regression models to determine the best fit relationship between root cause consequence and likelihood values and the input factors of interest. These root causes are combined into seven overall CubeSat mission risks which are then graphed on the industry-standard 5×5 Likelihood-Consequence (L-C) chart to help mission designers quickly identify areas of concern within their mission. This paper is the first to document not only the creation of a historical database of CubeSat mission risks, but, more importantly, the scientific representation of Risk Estimating Relationships.

  18. The Iodine Satellite (iSat) Project Development Towards Critical Design Review

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Calvert, Derek; Kamhawi, Hani; Hickman, Tyler; Szabo, James; Byrne, Lawrence

    2015-01-01

    Despite the prevalence of small satellites in recent years, the systems flown to date have very limited propulsion capability. SmallSats are typically secondary payloads and have significant constraints for volume, mass, and power in addition to limitations on the use of hazardous propellants or stored energy. These constraints limit the options for SmallSat maneuverability. NASA's Space Technology Mission Directorate approved the iodine Satellite flight project for a rapid demonstration of iodine Hall thruster technology in a 12U (cubesat units) configuration under the Small Spacecraft Technology Program. The mission is a partnership between NASA MSFC, NASA GRC, and Busek Co, Inc., with the Air Force supporting the propulsion technology maturation. The team is working towards the critical design review in the final design and fabrication phase of the project. The current design shows positive technical performance margins in all areas. The iSat project is planned for launch readiness in the spring of 2017.

  19. Coastal sea level from inland CryoSat-2 interferometric SAR altimetry

    NASA Astrophysics Data System (ADS)

    Abulaitijiang, Adili; Andersen, Ole Baltazar; Stenseng, Lars

    2015-03-01

    The European Space Agency's CryoSat-2 satellite can operate in a novel synthetic aperture radar interferometric (SARIn) mode where its nominal footprint (swath) is observed by two antennas and the phase difference between the signals is used to determination the exact location of the scatterer through an off-nadir correction. The potential of SARIn for sea level determination is investigated over the fjords of Eastern Greenland. In principle the satellite should only track sea level within its nominal footprint of 7 km across track, but we observe that scattering targets (fjords) within twice its nominal footprint are frequently observed but mislocated in CryoSat-2 due to phase wrapping. We devised a way to relocate the observations and correct the range accordingly. When CryoSat-2 is flying inland we consequently observed that the satellite occasionally provide valid sea level in fjords up to 13 km away in the across-track direction.

  20. CloudSat First Image of a Warm Front Storm Over the Norwegian Sea

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1

    CloudSat's first image, of a warm front storm over the Norwegian Sea, was obtained on May 20, 2006. In this horizontal cross-section of clouds, warm air is seen rising over colder air as the satellite travels from right to left. The red colors are indicative of highly reflective particles such as water droplets (or rain) or larger ice crystals (or snow), while the blue indicates thinner clouds (such as cirrus). The flat green/blue lines across the bottom represent the ground signal. The vertical scale on the CloudSat Cloud Profiling Radar image is approximately 30 kilometers (19 miles). The blue line below the Cloud Profiling Radar image indicates that the data were taken over water. The inset image shows the CloudSat track relative to a Moderate Resolution Imaging Spectroradiometer (MODIS) infrared image taken at nearly the same time.

  1. CHARM: A CubeSat Water Vapor Radiometer for Earth Science

    NASA Technical Reports Server (NTRS)

    Lim, Boon; Mauro, David; DeRosee, Rodolphe; Sorgenfrei, Matthew; Vance, Steve

    2012-01-01

    The Jet Propulsion Laboratory (JPL) and Ames Research Center (ARC) are partnering in the CubeSat Hydrometric Atmospheric Radiometer Mission (CHARM), a water vapor radiometer integrated on a 3U CubeSat platform, selected for implementation under NASA Hands-On Project Experience (HOPE-3). CHARM will measure 4 channels at 183 GHz water vapor line, subsets of measurements currently performed by larger and more costly spacecraft (e.g. ATMS, AMSU-B and SSMI/S). While flying a payload that supports SMD science objectives, CHARM provides a hands-on opportunity to develop technical, leadership, and project skills. CHARM will furthermore advance the technology readiness level (TRL) of the 183 GHz receiver subsystem from TRL 4 to TRL 6 and the CubeSat 183 GHz radiometer system from TRL 4 to TRL 7.

  2. The Iodine Satellite (iSat) Project Development Towards Critical Design Review (CDR)

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Selby, Michael; Polzin, Kurt A.; Kamhawi, Hani; Hickman, Tyler; Byrne, Larry

    2016-01-01

    Despite the prevalence of Small Satellites in recent years, the systems flown to date have very limited propulsion capability. SmallSats are typically secondary payloads and have significant constraints for volume, mass, and power in addition to limitations on the use of hazardous propellants or stored energy (i.e. high pressure vessels). These constraints limit the options for SmallSat maneuverability. NASA's Space Technology Mission Directorate approved the iodine Satellite flight project for a rapid demonstration of iodine Hall thruster technology in a 12U configuration under the Small Spacecraft Technology Program. The project formally began in FY15 as a partnership between NASA MSFC, NASA GRC, and Busek Co, Inc., with the Air Force supporting the propulsion technology maturation. The team is in final preparation of the Critical Design Review prior to initiating the fabrication and integration phase of the project. The iSat project is on schedule for a launch opportunity in November 2017.

  3. Integrating BalloonSAT and Atmospheric Dynamic Concepts into the Secondary Classroom

    NASA Astrophysics Data System (ADS)

    Fong, B. N.; Kennon, J. T.; Roberts, E.

    2016-05-01

    Arkansas BalloonSAT is an educational outreach and scientific research program that is part of Arkansas State University in Jonesboro, AR. The following is a unit of instruction to incorporate BalloonSAT measurements into secondary science classes. Students interpret graphs and identify several atmospheric trends and properties of a typical balloon flight. Students engage critical thinking skills in developing and answering their own questions relevant to the BalloonSAT program. Prerequisite concepts students should know are how to interpret graphs and unit conversions. Students should have a basic understanding of gravity, units of temperature and distance, and error in measurements. The unit is designed for one week after end-of-course exams and before the end of school. The unit may take two to five 50-minute periods, depending on how many activities are completed.

  4. A variable neighborhood Walksat-based algorithm for MAX-SAT problems.

    PubMed

    Bouhmala, Noureddine

    2014-01-01

    The simplicity of the maximum satisfiability problem (MAX-SAT) combined with its applicability in many areas of artificial intelligence and computing science made it one of the fundamental optimization problems. This NP-complete problem refers to the task of finding a variable assignment that satisfies the maximum number of clauses (or the sum of weights of satisfied clauses) in a Boolean formula. The Walksat algorithm is considered to be the main skeleton underlying almost all local search algorithms for MAX-SAT. Most local search algorithms including Walksat rely on the 1-flip neighborhood structure. This paper introduces a variable neighborhood walksat-based algorithm. The neighborhood structure can be combined easily using any local search algorithm. Its effectiveness is compared with existing algorithms using 1-flip neighborhood structure and solvers such as CCLS and Optimax from the eighth MAX-SAT evaluation. PMID:25177732

  5. A Variable Neighborhood Walksat-Based Algorithm for MAX-SAT Problems

    PubMed Central

    Bouhmala, Noureddine

    2014-01-01

    The simplicity of the maximum satisfiability problem (MAX-SAT) combined with its applicability in many areas of artificial intelligence and computing science made it one of the fundamental optimization problems. This NP-complete problem refers to the task of finding a variable assignment that satisfies the maximum number of clauses (or the sum of weights of satisfied clauses) in a Boolean formula. The Walksat algorithm is considered to be the main skeleton underlying almost all local search algorithms for MAX-SAT. Most local search algorithms including Walksat rely on the 1-flip neighborhood structure. This paper introduces a variable neighborhood walksat-based algorithm. The neighborhood structure can be combined easily using any local search algorithm. Its effectiveness is compared with existing algorithms using 1-flip neighborhood structure and solvers such as CCLS and Optimax from the eighth MAX-SAT evaluation. PMID:25177732

  6. Integration of CubeSat Systems with Europa Surface Exploration Missions

    NASA Astrophysics Data System (ADS)

    Erdoǧan, Enes; Inalhan, Gokhan; Kemal Üre, Nazım

    2016-07-01

    Recent studies show that there is a high probability that a liquid ocean exists under thick icy surface of Jupiter's Moon Europa. The findings also show that Europa has features that are similar to Earth, such as geological activities. As a result of these studies, Europa has promising environment of being habitable and currently there are many missions in both planning and execution level that target Europa. However, these missions usually involve extremely high budgets over extended periods of time. The objective of this talk is to argue that the mission costs can be reduced significantly by integrating CubeSat systems within Europa exploration missions. In particular, we introduce an integrated CubeSat-micro probe system, which can be used for measuring the size and depth of the hypothetical liquid ocean under the icy surface of Europa. The systems consist of an entry module that houses a CubeSat combined with driller measurement probes. Driller measurement probes deploy before the system hits the surface and penetrate the surface layers of Europa. Moreover, a micro laser probe could be used to examine the layers. This process enables investigation of the properties of the icy layer and the environment beneath the surface. Through examination of different scenarios and cost analysis of the components, we show that the proposed CubeSat systems has a significant potential to reduce the cost of the overall mission. Both subsystem requirements and launch prices of CubeSats are dramatically cheaper than currently used satellites. In addition, multiple CubeSats may be used to dominate wider area in space and they are expandable in face of potential failures. In this talk we discuss both the mission design and cost reduction aspects.

  7. The effects of a Self-Alert Training (SAT) program in adults with ADHD.

    PubMed

    Salomone, Simona; Fleming, Grainne R; Shanahan, Jacqueline M; Castorina, Marco; Bramham, Jessica; O'Connell, Redmond G; Robertson, Ian H

    2015-01-01

    Attention-Deficit/Hyperactivity Disorder (ADHD), a neuropsychiatric condition characterized by attention and impulsivity problems, is one of the most common behavioral disorders. The first line of treatment for ADHD is psychostimulant medication, but this has limited effectiveness, particularly in adults, and is often associated with adverse side-effects. Thus, it is imperative that new non-pharmaceutical approaches to treatment are developed. This study aims to evaluate the impact of a non-pharmacological Self-Alert Training (SAT) intervention on ADHD symptom prevalence, psychological and cognitive functioning, and on everyday functional impairment in adults with ADHD. Fifty-one adult participants with a current diagnosis of ADHD were randomized to either SAT or a Control Training (CT) program. They were assessed at baseline, immediately following the 5-week training period, and after 3-months using ADHD symptoms scales, as well as a series of neuropsychological tests and psychological questionnaires. Subjective ratings of everyday life attention and memory problems were also collected. The SAT group showed significant improvements in ADHD inattentive and impulsive symptoms, depressive symptoms and in self-efficacy ratings compared to the CT group at both post-training and at the 3-month assessment. Pre-post improvements in SAT participants on untrained cognitive tasks measuring selective attention and executive functions were also observed. Finally, the SAT group reported improved subjective ratings of everyday life attention at both assessment points. This pattern of results suggests that SAT may be beneficial in treating ADHD symptoms as well as psychological and cognitive impairments in adult ADHD. A large-scale randomized controlled trial (RCT) is needed. PMID:25713523

  8. The effects of a Self-Alert Training (SAT) program in adults with ADHD

    PubMed Central

    Salomone, Simona; Fleming, Grainne R.; Shanahan, Jacqueline M.; Castorina, Marco; Bramham, Jessica; O’Connell, Redmond G.; Robertson, Ian H.

    2015-01-01

    Attention-Deficit/Hyperactivity Disorder (ADHD), a neuropsychiatric condition characterized by attention and impulsivity problems, is one of the most common behavioral disorders. The first line of treatment for ADHD is psychostimulant medication, but this has limited effectiveness, particularly in adults, and is often associated with adverse side-effects. Thus, it is imperative that new non-pharmaceutical approaches to treatment are developed. This study aims to evaluate the impact of a non-pharmacological Self-Alert Training (SAT) intervention on ADHD symptom prevalence, psychological and cognitive functioning, and on everyday functional impairment in adults with ADHD. Fifty-one adult participants with a current diagnosis of ADHD were randomized to either SAT or a Control Training (CT) program. They were assessed at baseline, immediately following the 5-week training period, and after 3-months using ADHD symptoms scales, as well as a series of neuropsychological tests and psychological questionnaires. Subjective ratings of everyday life attention and memory problems were also collected. The SAT group showed significant improvements in ADHD inattentive and impulsive symptoms, depressive symptoms and in self-efficacy ratings compared to the CT group at both post-training and at the 3-month assessment. Pre-post improvements in SAT participants on untrained cognitive tasks measuring selective attention and executive functions were also observed. Finally, the SAT group reported improved subjective ratings of everyday life attention at both assessment points. This pattern of results suggests that SAT may be beneficial in treating ADHD symptoms as well as psychological and cognitive impairments in adult ADHD. A large-scale randomized controlled trial (RCT) is needed. PMID:25713523

  9. Ability of sat-1 to transport sulfate, bicarbonate, or oxalate under physiological conditions.

    PubMed

    Krick, Wolfgang; Schnedler, Nina; Burckhardt, Gerhard; Burckhardt, Birgitta C

    2009-07-01

    Tubular reabsorption of sulfate is achieved by the sodium-dependent sulfate transporter, NaSi-1, located at the apical membrane, and the sulfate-anion exchanger, sat-1, located at the basolateral membrane. To delineate the physiological role of rat sat-1, [(35)S]sulfate and [(14)C]oxalate uptake into sat-1-expressing oocytes was determined under various experimental conditions. Influx of [(35)S]sulfate was inhibited by bicarbonate, thiosulfate, sulfite, and oxalate, but not by sulfamate and sulfide, in a competitive manner with K(i) values of 2.7 +/- 1.3 mM, 101.7 +/- 9.7 microM, 53.8 +/- 10.9 microM, and 63.5 +/- 38.7 microM, respectively. Vice versa, [(14)C]oxalate uptake was inhibited by sulfate with a K(i) of 85.9 +/- 9.5 microM. The competitive type of inhibition indicates that these compounds are most likely substrates of sat-1. Physiological plasma bicarbonate concentrations (25 mM) reduced sulfate and oxalate uptake by more than 75%. Simultaneous application of sulfate, bicarbonate, and oxalate abolished sulfate as well as oxalate uptake. These data and electrophysiological studies using a two-electrode voltage-clamp device provide evidence that sat-1 preferentially works as an electroneutral sulfate-bicarbonate or oxalate-bicarbonate exchanger. In kidney proximal tubule cells, sat-1 likely completes sulfate reabsorption from the ultrafiltrate across the basolateral membrane in exchange for bicarbonate. In hepatocytes, oxalate extrusion is most probably mediated either by an exchange for sulfate or bicarbonate. PMID:19369292

  10. A CubeSat to Search for Transiting Planets Around the Young Star Beta Pictoris

    NASA Astrophysics Data System (ADS)

    Blake, Ameer; Roberge, Aki

    2016-01-01

    The goal of this project is to further our growing knowledge of exoplanets in the solar neighborhood. The nearby star Beta Pictoris, which is nearly twice the mass of the Sun, is encircled by a huge disk of dust and gas reaching out 500-800 AU from the star. This so-called "debris disk" is the product of collisions between large numbers of asteroids and comets orbiting this relatively young star. The presence of these small planetary bodies hinted that there might be planets in the disk as well, which was recently confirmed when a ground-based telescope directly imaged a super-Jupiter exoplanet orbiting the star.The debris disk of Beta Pic tells us that this planetary system is edge-on from our vantage point on Earth. Therefore, it is an ideal system to use transit photometry to search for additional planets. We hope to due so by monitoring the brightness of the star over a given period, using a telescope on small satellite (a CubeSat). A CubeSat is a very small satellite tasked with a single purpose and, in this case, a single target. The advantage of a CubeSat over a larger telescope is the low cost and fast development schedule. Since we wish to study only one star's system, a CubeSat is an economical choice, although the limited lifetime of a CubeSat means that only planets with relatively short (up to few month) periods may be found. Our preliminary calculations show that, in principle, we can discover planets from Jupiter-size down to Neptune-size around Beta Pic with a telescope sized to fit in a CubeSat.

  11. ABDOMINAL SUBCUTANEOUS ADIPOSE TISSUE (SAT) AND VICERAL ADIPOSE TISSUE (VAT) MEASUREMENTS IN HIV+ ADULTS: INFLUENCES OF MEASUREMENT SITE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Loss of SAT and an increase in VAT are common with HIV lipodystrophy. Excess abdominal VAT is a known risk factor for cardiovascular disease. Computerized axial tomography (CT) can be used to measure SAT and VAT areas in cross-sectional images of the abdomen. The ideal site(s) and number of abdomina...

  12. Assessing Statistics Attitudes among College Students: Psychometric Properties of the Italian Version of the "Survey of Attitudes toward Statistics (SATS)"

    ERIC Educational Resources Information Center

    Chiesi, Francesca; Primi, Caterina

    2009-01-01

    The aim of the present research was to test the psychometric properties of the Italian version of the Survey of Attitudes Toward Statistics (SATS) in order to acquire a valid instrument to measure attitudes inside the Italian educational context. The SATS was administered to Italian-speaking undergraduate students enrolled in introductory…

  13. Racial Differences in Test Preparation Strategies: A Commentary on "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment"

    ERIC Educational Resources Information Center

    Alon, Sigal

    2010-01-01

    Claudia Buchmann, Dennis Condron and Vincent Roscigno's study, titled "Shadow Education, American Style: Test Preparation, the SAT and College Enrollment," demonstrates that vigorous use of expensive test preparation tools, such as private classes and tutors, significantly boosts scores on standardized exams such as the SAT or ACT. This…

  14. Cultural Disparities of SAT Scores and the Influence on Higher Education Opportunities for African American and Latino Students

    ERIC Educational Resources Information Center

    Hoover, Nichelle

    2007-01-01

    Inequalities in the distribution of education resources and cultural identification can lead to lower SAT scores for African American and Latino students. By using SAT scores as one of the primary sources to determine admission to institutions of higher education, educators may be denying minority students admission to a variety of colleges and…

  15. The Black-White Scoring Gap on SAT II Achievement Tests: Some of the News Is Cheering.

    ERIC Educational Resources Information Center

    Journal of Blacks in Higher Education, 2003

    2003-01-01

    Academically accomplished applicants to the nation's top colleges usually take SAT II Achievement Tests. While scoring gaps between college-bound Blacks and Whites on these tests tend to be smaller than gaps on the basic SAT, a racial scoring gap persists. However, black students appear to be making progress in closing the racial scoring gap on…

  16. Setting Local Cut Scores on the Sat Reasoning Test™ Writing Section: For Use in College Placement and Admissions Decisions

    ERIC Educational Resources Information Center

    Morgan, Deanna L.

    2006-01-01

    The introduction of the SAT Reasoning Test™ with a writing section in March 2005 and the concomitant elimination of the SAT® Subject Test in Writing after January 2005 have led many colleges and institutions to ask for guidance in using the new SAT Reasoning Test writing section scores for college placement and admissions. Standard-setting…

  17. The Effect of the BalloonSat Project on Middle and High School Students' Attitude toward Science

    ERIC Educational Resources Information Center

    Verhage, L. Paul

    2012-01-01

    This study measured the effect of completing a BalloonSat project on student attitude toward science. Seven categories of student attitudes toward science were measured using the Test of Science Relate Attitudes survey (TOSRA). The research anticipated that the BalloonSat project would have similar effects on student attitudes as found in robotics…

  18. SAT Participation and Performance and the Attainment of College and Career Readiness Benchmark Scores for the Class of 2013. Memorandum

    ERIC Educational Resources Information Center

    Sanderson, Geoffrey T.

    2013-01-01

    This memorandum describes the SAT participation and performance for the Montgomery County (Maryland) Public Schools (MCPS) Class of 2013 compared with the graduating seniors in Maryland and the nation. Detailed results of SAT and ACT by high school and student group for graduates in 2011-2013 are included. MCPS students continue to outperform the…

  19. Synthesis of Recent SAT Validity Findings: Trend Data over Time and Cohorts. Research in Review 2014-1

    ERIC Educational Resources Information Center

    Mattern, Krista D.; Patterson, Brian F.

    2014-01-01

    In March 2005, substantial revisions were made to the SAT, to better align test specifications with K-12 curriculum (Lawrence, Rigol, Van Essen & Jackson, 2003). Over the last five years, the College Board has made a concerted effort to collect higher education outcome data to document evidence of the validity of the SAT for use in college…

  20. Sustained attention in mice: expanding the translational utility of the SAT by incorporating the Michigan Controlled Access Response Port (MICARP).

    PubMed

    St Peters, Megan; Cherian, Ajeesh Koshy; Bradshaw, Marc; Sarter, Martin

    2011-12-01

    Advances in mouse genetic technology have spurred increasing interest in the development of cognitive tasks for mice. Here, we describe and discuss the modifications necessary to adapt a task for the assessment of sustained attention performance for use in mice, including for taxing the top-down control of such performance. The validity of the Sustained Attention Task (SAT), including the distractor version (dSAT), has previously been demonstrated in rats and humans. This task requires moveable or retractable operanda; insertion of operanda into the operant chambers cues animals to respond to a prior signal or non-signal event, reporting either a hit or a miss, or a correct rejection or false alarm, respectively. Retractable levers did not support sufficiently high and stable levels of performance in mice. Given the widespread use of static nose-poke devices for testing operant performance in mice, we therefore designed and fabricated a retractable nose-poke device. As this device extends into chambers, a hole for nose-poking is slowly opened and closed again as the device retracts (termed the "Michigan Controlled Access Response Port", MICARP). Results describe the effects of variation of signal duration and event rate, trial outcome and trial type probability, effects of mice deprivation levels, and the reliability of SAT and dSAT performance. Mice perform the SAT and dSAT at levels comparable to those observed in rats. This task will be of assistance in expanding the translational usefulness of the SAT and dSAT. PMID:21888929

  1. Assimilation of CryoSat-2 altimetry to a hydrodynamic model of the Brahmaputra river

    NASA Astrophysics Data System (ADS)

    Schneider, Raphael; Nygaard Godiksen, Peter; Ridler, Marc-Etienne; Madsen, Henrik; Bauer-Gottwein, Peter

    2016-04-01

    Remote sensing provides valuable data for parameterization and updating of hydrological models, for example water level measurements of inland water bodies from satellite radar altimeters. Satellite altimetry data from repeat-orbit missions such as Envisat, ERS or Jason has been used in many studies, also synthetic wide-swath altimetry data as expected from the SWOT mission. This study is one of the first hydrologic applications of altimetry data from a drifting orbit satellite mission, namely CryoSat-2. CryoSat-2 is equipped with the SIRAL instrument, a new type of radar altimeter similar to SRAL on Sentinel-3. CryoSat-2 SARIn level 2 data is used to improve a 1D hydrodynamic model of the Brahmaputra river basin in South Asia set up in the DHI MIKE 11 software. CryoSat-2 water levels were extracted over river masks derived from Landsat imagery. After discharge calibration, simulated water levels were fitted to the CryoSat-2 data along the Assam valley by adapting cross section shapes and datums. The resulting hydrodynamic model shows accurate spatio-temporal representation of water levels, which is a prerequisite for real-time model updating by assimilation of CryoSat-2 altimetry or multi-mission data in general. For this task, a data assimilation framework has been developed and linked with the MIKE 11 model. It is a flexible framework that can assimilate water level data which are arbitrarily distributed in time and space. Different types of error models, data assimilation methods, etc. can easily be used and tested. Furthermore, it is not only possible to update the water level of the hydrodynamic model, but also the states of the rainfall-runoff models providing the forcing of the hydrodynamic model. The setup has been used to assimilate CryoSat-2 observations over the Assam valley for the years 2010 to 2013. Different data assimilation methods and localizations were tested, together with different model error representations. Furthermore, the impact of

  2. The QBito CubeSat: Applications in Space Engineering Education at Technical University of Madrid

    NASA Astrophysics Data System (ADS)

    Fernandez Fraile, Jose Javier; Laverón-Simavilla, Ana; Calvo, Daniel; Moreno Benavides, Efren

    The QBito CubeSat is one of the 50 CubeSats that is being developed for the QB50 project. The project is funded by the 7 (th) Frame Program to launch 50 CubeSats in a ‘string-of-pearls’ configuration for multi-point, in-situ measurements in the lower thermosphere and re-entry research. The 50 CubeSats, developed by an international network of universities and research institutions, will comprise 40 double CubeSats with atmospheric sensors and 10 double or triple CubeSats for science and technology demonstration. It will be the first large-scale CubeSat constellation in orbit; a concept that has been under discussion for several years but not implemented up to now. This project has a high educational interest for universities; beyond the scientific and technological results, being part of an international group of over 90 universities all over the world working and sharing knowledge to achieve a successful mission represents an exciting opportunity. The QBito project main educational motivation is to educate students in space technologies and in space systems engineering. The Universidad Politécnica de Madrid (UPM) is designing, developing, building and testing one of the double CubeSats carrying as payload a kit of atmospheric sensors from the consortium, and other payloads developed by the team such as an IR non-refrigerated sensor, a Phase Change Material (PCM) for thermal control applications, a Fuzzy Logic Attitude Control System and other technological developments such as an optimized antenna deployment mechanism, a lightweight multi-mission configurable structure, and an efficient Electric Power System (EPS) with a Maximum Peak Power Tracker (MPPT). This project has been integrated in the training of the Aerospatiale Engineering, Master and PhD degree students by involving them in the complete engineering process, from its conceptual design to the post-flight conclusions. Three subsystems have been selected for being developed from the conceptual design

  3. ASPECT spectral imaging satellite proposal to AIDA/AIM CubeSat payload

    NASA Astrophysics Data System (ADS)

    Kohout, Tomas; Näsilä, Antti; Tikka, Tuomas; Penttilä, Antti; Muinonen, Karri; Kestilä, Antti; Granvik, Mikael; Kallio, Esa

    2016-04-01

    ASPECT (Asteroid Spectral Imaging Mission) is a part of AIDA/AIM project and aims to study the composition of the Didymos binary asteroid and the effects of space weathering and shock metamorphism in order to gain understanding of the formation and evolution of the Solar System. The joint ESA/NASA AIDA (Asteroid Impact & Deflection Assessment) mission to binary asteroid Didymos consists of AIM (Asteroid Impact Mission, ESA) and DART (Double Asteroid Redirection Test, NASA). DART is targeted to impact Didymos secondary component (Didymoon) and serve as a kinetic impactor to demonstrate deflection of potentially hazardous asteroids. AIM will serve as an observational spacecraft to evaluate the effects of the impact and resulting changes in the Didymos dynamic parameters. The AIM mission will also carry two CubeSat miniaturized satellites, released in Didymoon proximity. This arrangement opens up a possibility for secondary scientific experiments. ASPECT is one of the proposed CubeSat payloads. Whereas Didymos is a space-weathered binary asteroid, the DART impactor is expected to produce a crater and excavate fresh material from the secondary component (Didymoon). Spectral comparison of the mature surface to the freshly exposed material will allow to directly deter-mine space weathering effects. It will be also possible to study spectral shock effects within the impact crater. ASPECT will also demonstrate for the first time the joint spacecraft - CubeSat operations in asteroid proximity and miniature spectral imager operation in deep-space environment. Science objectives: 1. Study of the surface composition of the Didymos system. 2. Photometric observations (and modeling) under varying phase angle and distance. 3. Study of space weathering effects on asteroids (comparison of mature / freshly exposed material). 4. Study of shock effects (spectral properties of crater interior). 5. Observations during the DART impact. Engineering objectives: 1. Demonstration of CubeSat

  4. Constellation of CubeSats for Realtime Ionospheric E-field Measurements for Global Space Weather

    NASA Astrophysics Data System (ADS)

    Crowley, G.; Swenson, C.; Pilinski, M.; Fish, C. S.; Neilsen, T. L.; Stromberg, E. M.; Azeem, I.; Barjatya, A.

    2014-12-01

    Inexpensive and robust space-weather monitoring instruments are needed to fill upcoming gaps in the Nation's ability to meet requirements for space weather specification and forecasting. Foremost among the needed data are electric fields, since they drive global ionospheric and thermospheric behavior, and because there are relatively few ground-based measurements. We envisage a constellation of CubeSats to provide global coverage of the electric field and its variability. The DICE (Dynamic Ionosphere CubeSat Experiment) mission was a step towards this goal, with two identical 1.5U CubeSats, each carrying three space weather instruments: (1) double probe instruments to measure AC and DC electric fields; (2) Langmuir probes to measure ionospheric electron density, and; (3) a magnetometer to measure field-aligned currents. DICE launched in October 2011. DICE was the first CubeSat mission to observe a Storm Enhanced Density event, fulfilling a major goal of the mission. Due to attitude control anomalies encountered in orbit, the DICE electric field booms have not yet been deployed. Important lessons have been learned for the implementation of a spin-stabilized CubeSat, and the design and performance of the Attitude Determination & Control System (ADCS). These lessons are now being applied to the DIME SensorSat, a risk-reduction mission that is capable of deploying flexible electric field booms up to a distance of 10-m tip-to-tip from a 1.5U CubeSat. DIME will measure AC and DC electric fields, and will exceed several IORD-2 threshold requirements. Ion densities, and magnetic fields will also be measured to characterize the performance of the sensor in different plasma environments. We show the utility of a constellation of electric field measurements, describe the DIME SensorSat, and demonstrate how the measurement will meet or exceed IORD requirements. The reduced cost of these sensors will enable constellations that can, for the first time, adequately resolve the

  5. Analysis of reentry into the White Sands Missile Range (WSMR) for the LifeSat mission

    NASA Technical Reports Server (NTRS)

    Hametz, M.; Roszman, L.; Snow, F.; Cooley, J.

    1993-01-01

    This study investigates the reentry of the LifeSat vehicles into the WSMR. The LifeSat mission consists of two reusable reentry satellites, each carrying a removable payload module, which scientists will use to study long-term effects of microgravity, Van Allen belt radiation, and galactic cosmic rays on living organisms. A series of missions is planned for both low-Earth circular orbits and highly elliptic orbits. To recover the payload module with the specimens intact, a soft parachute landing and recovery at the WSMR is planned. This analysis examines operational issues surrounding the reentry scenario to assess the feasibility of the reentry.

  6. Integrated monitoring technologies for the management of a Soil-Aquifer-Treatment (SAT) system.

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Alexandros; Kallioras, Andreas; Kofakis, Petros; Bumberger, Jan; Schmidt, Felix; Athanasiou, Georgios; Uzunoglou, Nikolaos; Amditis, Angelos; Dietrich, Peter

    2016-04-01

    Artificial recharge of groundwater has an important role to play in water reuse as treated wastewater effluent can be infiltrated into the ground for aquifer recharge. As the effluent moves through the soil and the aquifer, it undergoes significant quality improvements through physical, chemical, and biological processes in the underground environment. Collectively, these processes and the water quality improvement obtained are called soil-aquifer-treatment (SAT) or geopurification. The pilot site of Lavrion Technological & Cultural Park (LTCP) of the National Technical University of Athens (NTUA), involves the employment of plot infiltration basins at experimental scale, which will be using waters of impaired quality as a recharge source, and hence acting as a Soil-Aquifer-Treatment, SAT, system. Τhe LTCP site will be employed as a pilot SAT system complemented by new technological developments, which will be providing continuous monitoring of the quantitative and qualitative characteristics of infiltrating groundwater through all hydrologic zones (i.e. surface, unsaturated and saturated zone). This will be achieved by the development and installation of an integrated system of prototype sensing technologies, installed on-site, and offering a continuous evaluation of the performance of the SAT system. An integrated approach of the performance evaluation of any operating SAT system should aim at parallel monitoring of all hydrologic zones, proving the sustainability of all involved water quality treatment processes within unsaturated and saturated zone. Hence a prototype system of Time and Frequency Domain Reflectometry (TDR & FDR) sensors is developed and will be installed, in order to achieve continuous quantitative monitoring of the unsaturated zone through the entire soil column down to significant depths below the SAT basin. Additionally, the system contains two different radar-based sensing systems that will be offering (i) identification of preferential

  7. A SAT Based Effective Algorithm for the Directed Hamiltonian Cycle Problem

    NASA Astrophysics Data System (ADS)

    Jäger, Gerold; Zhang, Weixiong

    The Hamiltonian cycle problem (HCP) is an important combinatorial problem with applications in many areas. While thorough theoretical and experimental analyses have been made on the HCP in undirected graphs, little is known for the HCP in directed graphs (DHCP). The contribution of this work is an effective algorithm for the DHCP. Our algorithm explores and exploits the close relationship between the DHCP and the Assignment Problem (AP) and utilizes a technique based on Boolean satisfiability (SAT). By combining effective algorithms for the AP and SAT, our algorithm significantly outperforms previous exact DHCP algorithms including an algorithm based on the award-winning Concorde TSP algorithm.

  8. Using SAT scores to identify students at risk in introductory physics

    NASA Astrophysics Data System (ADS)

    Coletta, Vincent P.; Phillips, J.

    2006-12-01

    Our previous research has shown a strong correlation between individual students’ pre-instruction scores on Lawson’s Test of Reasoning Ability and their normalized gains on the FCI. These results have been replicated by researchers at Edward Little High School in Maine, at the University of Colorado, and at the University of Central Florida. We now find that SAT scores also provide a strong correlation with FCI gains. The advantage of using SAT scores is that one does not have to administer another test; these scores are usually readily available through the registrar’s office.

  9. Genetic relationships between southern African SAT-2 isolates of foot-and-mouth-disease virus.

    PubMed Central

    Vosloo, W.; Knowles, N. J.; Thomson, G. R.

    1992-01-01

    Sequencing of part of the 1D gene of foot-and-mouth disease virus was used to determine the relationships between SAT-2 viruses isolated from outbreaks which occurred in cattle in Zimbabwe and Namibia and in impala in South Africa between 1979 and 1989. The results demonstrated that the outbreaks in different countries were unrelated. Surprisingly close relationships were shown between all SAT-2 viruses isolated from cattle in Zimbabwe since 1983 but the two major epizootics which occurred in 1989 were caused by viruses which were clearly different. Conversely, two apparently unrelated outbreaks in impala in South Africa were caused by viruses which could not be distinguished. PMID:1334842

  10. Crystal structure of bis-(tri-ethano-lamine-κ(3) N,O,O')nickel(II) bis-(3-hy-droxy-benzoate) tetra-hydrate.

    PubMed

    Ibragimov, Aziz B

    2016-05-01

    The reaction of 3-hy-droxy-benzoic (m-hy-droxy-benzoic) acid (MHBA), tri-ethano-lamine (TEA) and Ni(NO3)2 in aqueous solution led to formation of the hydrated title salt, [Ni(C6H15NO3)2](C7H5O3)·4H2O. In the complex cation, the Ni(2+) ion is located on an inversion centre. Two symmetry-related TEA ligands occupy all coordination sites in an N,O,O'-tridentate coordination, leading to a slightly distorted NiN2O4 octa-hedron. Two ethanol groups of each TEA ligand form two five-membered chelate rings around Ni(2+), while the third ethanol group does not coordinate to the metal atom. Two MHBA(-) anions in the benzoate form are situated in the outer coordination sphere for charge compensation. An intricate network of hydrogen bonds between the free and coordinating hy-droxy groups of the TEA ligands, the O atoms of the MHBA(-) anions and the water mol-ecules leads to the formation of a two-dimensional structure extending parallel to (010). PMID:27308009

  11. The Utility of the SAT® I and SAT II for Admissions Decisions in California and the Nation. Research Report No. 2002-6

    ERIC Educational Resources Information Center

    Kobrin, Jennifer L.; Camara, Wayne J.; Milewski, Glenn B.

    2002-01-01

    This study examines the relative utility and predictive validity of the SAT I and SAT II for various subgroups in both California and the nation. The effect of eliminating the SAT I on the test impact and on the over- and under-prediction of various gender and racial/ethnic subgroups is examined. Two statistical adjustments and tables are appended.

  12. Polar stratospheric clouds observed at Eureka (80°N, 86°W) in the Canadian Arctic during the 1994/1995 winter

    NASA Astrophysics Data System (ADS)

    Nagai, T.; Uchino, O.; Itabe, T.; Shibata, T.; Mizutani, K.; Fujimoto, T.

    1997-09-01

    A lidar system was installed at Eureka (80°N, 86°W) in January 1993 to monitor stratospheric aerosols and polar stratospheric clouds (PSCs). In the winter of 1994/1995, PSCs were found at altitudes of around 20km in the middle of December. In early January 1995, PSCs were observed at altitudes from 14.3 km to 16 km, where the temperature ranged from 199K to 202K. Since this range is higher than the frost point of nitric acid trihydrate (NAT), the particles in these PSCs may have consisted of sulfuric acid tetrahydrate (SAT).

  13. Accuracy analysis of CryoSat-2 SARIn mode data over Antarctica

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Bamber, Jonathan; Cheng, Xiao

    2015-04-01

    In 2010, CryoSat-2 was launched, carrying a unique satellite radar altimetry (SRA) instrument called SAR/Interferometric Radar Altimeter (SIRAL), with the aim of measuring and monitoring sea ice, ice sheets and mountain glaciers. The novel SAR Interferometric mode (SARInM) of CryoSat-2 is designed to improve the accuracy, resolution and geolocation of height measurements over the steeper margins of ice sheets and ice caps. Over these areas, it employs the synthetic aperture radar (SAR) capability to reduce the size of the footprint to effectively 450m along track and ~1km across track implemented from an airborne prototype originally termed a delay-Doppler altimeter. Additionally, CryoSat-2 used the phase difference between its two antennas to estimate surface slope in the across-track direction and identify the point of closed approach directly. The phase difference is 2pi for a surface slope of approximately 1deg. If the slope is above this threshold, the tracked surface in the returned waveform may be not the point of closed approach causing an error in slope correction. For this reason, the analysis was limited to slopes of 1deg or less in this study. We used extensive coverage of Antarctica provided by the ICESat laser altimeter mission between 2003 and 2009 to assess the accuracy of SARInM data. We corrected for changes in elevations due to the interval between the acquisition of the ICESat and CryoSat-2 data (from July 2010 and December 2013). Two methods were used: (1) the ICESat point was compared with a DEM derived from CryoSat-2 data (Point-to-DEM; PtoDEM), and (2) the ICESat point was compared with a CryoSat-2 point directly (Point-to-Point; PtoP). For PtoDEM, CryoSat-2 elevations were interpolated onto a regular 1km polar stereographic grid with a standard parallel of 71°S, using ordinary kriging. For PtoP, the maximum distance between a CryoSat-2 point location and ICESat point location was set to 35m. For the areas with slopes less than 0.2deg, the

  14. The MicroMAS CubeSat Mission

    NASA Astrophysics Data System (ADS)

    Cahoy, K.; Blackwell, W. J.; Allen, G.; Bury, M.; Efromson, R.; Galbraith, C.; Hancock, T.; Leslie, V.; Osaretin, I.; Retherford, L.; Scarito, M.; Shields, M.; Toher, D.; Wight, K.; Miller, D.; Marinan, A.; Paek, S.; Peters, E.; Schmidt, F. H.; Alvisio, B.; Wise, E.; Masterson, R.; Franzim Miranda, D.; Crail, C.; Kingsbury, R.; Souffrant, A.; Orrego, L.; Eslinger, G.; Nicholas, A.; Pong, C.

    2012-12-01

    The recently published Midterm Assessment of NASA's Implementation of the Decadal Survey finds that, "The nation's Earth observing system is beginning a rapid decline in capability as long-running missions end and key new missions are delayed, lost, or canceled. The projected loss of observing capability could have significant adverse consequences for science and society." In this presentation, we explore low-cost, mission-flexible, and rapidly deployable spaceborne sensors that can meet stringent performance requirements pervading the NASA Earth Science measurement programs, including especially the recommended NRC Decadal Survey missions. New technologies have enabled a novel approach toward this science observational goal, and in this paper we describe recent technology develop efforts to address the challenges above through the use of CubeSat radiometers. The Micro-sized Microwave Atmospheric Satellite (MicroMAS) is a 3U cubesat (30x10x10 cm, ~4kg) hosting a passive microwave spectrometer operating near the 118.75-GHz oxygen absorption line. The focus of the first MicroMAS mission (hereafter, MicroMAS-1) is to observe convective thunderstorms, tropical cyclones, and hurricanes from a near-equatorial orbit at approximately 500-km altitude. A MicroMAS flight unit is currently being developed in anticipation of a 2014 launch to be provided by NASA. A parabolic reflector is mechanically rotated as the spacecraft orbits the earth, thus directing a cross-track scanned beam with FWHM beamwidth of 2.4-degrees, yielding an approximately 25-km diameter footprint from a nominal altitude of 500 km. Radiometric calibration is carried out using observations of cold space, the earth's limb, and an internal noise diode that is weakly coupled through the RF front-end electronics. A key technology feature is the development of an ultra-compact intermediate frequency processor module for channelization, detection, and A-to-D conversion. The antenna system and RF front

  15. An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

    NASA Technical Reports Server (NTRS)

    Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel Chitra

    2016-01-01

    National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA). A study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper presents details of the simulation and analysis that include CubeSat swarm, daughter ship/mother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRSS Multiple Access (MA) array vs Single Access mode, notional transceiver/antenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter ship/mother ship CubeSat constellation inter-satellite cross link. Results of space science X-band 10 MHz maximum achievable data rate study are summarized. CubeSat NEN Ka-Band end-to-end communication analysis is provided. Current CubeSat communication technologies capabilities are presented. Compatibility test of the CubeSat transceiver through NEN and SN is discussed. Based on the analyses, signal trade studies and technology assessments, the desired CubeSat transceiver features and operation concepts for future CubeSat end-to-end communications are derived.

  16. Development of a Solar Array Drive Assembly for CubeSat

    NASA Technical Reports Server (NTRS)

    Passaretti, Mike; Hayes, Ron

    2010-01-01

    Small satellites and in particular CubeSats, have increasingly become more viable as platforms for payloads typically requiring much larger bus structures. As advances in technology make payloads and instruments for space missions smaller, lighter and more power efficient, a niche market is emerging from the university community to perform rapidly developed, low-cost missions on very small spacecraft - micro, nano, and picosatellites. In just the last few years, imaging, biological and new technology demonstration missions have been either proposed or have flown using variations of the CubeSat structure as a basis. As these missions have become more complex, and the CubeSat standard has increased in both size (number of cubes) and mass, available power has become an issue. Body-mounted solar cells provide a minimal amount of power; deployable arrays improve on that baseline but are still limited. To truly achieve maximum power, deployed tracked arrays are necessary. To this end, Honeybee Robotics Spacecraft Mechanisms Corporation, along with MMA of Nederland Colorado, has developed a solar array drive assembly (SADA) and deployable solar arrays specifically for CubeSat missions. In this paper, we discuss the development of the SADA.

  17. NASA Near Earth Network (NEN) and Space Network (SN) CubeSat Communications

    NASA Technical Reports Server (NTRS)

    Schaire, Scott H.; Shaw, Harry; Altunc, Serhat; Bussey, George; Celeste, Peter; Kegege, Obadiah; Wong, Yen; Zhang, Yuwen; Patel, Chitra; Raphael, David; Burke, Jacob; Cooper, La Vida; Schier, James; Horne, William; Pierce, David

    2016-01-01

    There has been a recent trend to increase capability and drive down the Size, Weight and Power (SWAP) of satellites. NASA scientists and engineers across many of NASA's Mission Directorates and Centers are developing exciting CubeSat concepts and welcome potential partnerships for CubeSat endeavors. From a "Telemetry, Tracking and Command (TT&C) Systems and Flight Operations for Small Satellites" point of view, small satellites including CubeSats are a challenge to coordinate because of existing small spacecraft constraints, such as limited SWAP and attitude control, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Program's Near Earth Network (NEN) and Space Network (SN) are customer driven organizations that provide comprehensive communications services for space assets including data transport between a mission's orbiting satellite and its Mission Operations Center (MOC). This paper presents how well the SCaN networks, SN and NEN, are currently positioned to support the emerging small small satellite and CubeSat market as well as planned enhancements for future support.

  18. NASA Near Earth Network (NEN) and Space Network (SN) Support of CubeSat Communications

    NASA Technical Reports Server (NTRS)

    Schaire, Scott H.; Shaw, Harry C.; Altunc, Serhat; Bussey, George; Celeste, Peter; Kegege, Obadiah; Wong, Yen; Zhang, Yuwen; Patel, Chitra; Raphael, David; Burke, Jacob; Cooper, La Vida; Schier, James; Horne, William; Pierce, David

    2016-01-01

    There has been a historical trend to increase capability and drive down the Size, Weight and Power (SWAP) of satellites and that trend continues today. NASA scientists and engineers across many of NASAs Mission Directorates and Centers are developing exciting CubeSat concepts and welcome potential partnerships for CubeSat endeavors. From a Telemetry, Tracking and Command (TTC) Systems and Flight Operations for Small Satellites point of view, small satellites including CubeSats are a challenge to coordinate because of existing small spacecraft constraints, such as limited SWAP and attitude control, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Programs Near Earth Network (NEN) and Space Network (SN) are customer driven organizations that provide comprehensive communications services for space assets including data transport between a missions orbiting satellite and its Mission Operations Center (MOC). This paper presents how well the SCaN networks, SN and NEN, are currently positioned to support the emerging small small satellite and CubeSat market as well as planned enhancements for future support.

  19. The Co-Sat Class: Strategies for Teaching Combined Levels of Developmental English

    ERIC Educational Resources Information Center

    Pireh, Diane Flanegan

    2009-01-01

    This article presents strategies for teaching a co-sat class, a class wherein students who place into two different levels of developmental English are taught concurrently in one classroom with one instructor. The article describes organizing the course on a framework of shared topics, includes a model for managing classroom activities, and gives…

  20. SAT Type Foot-and-Mouth Disease (FMD) Chimeric Vaccine Elicits Protection in Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent development of infectious cDNA clone technology for foot-and-mouth disease (FMD), Southern African Territories (SAT) viruses has provided a valuable tool for genetic and biological characterization of field and laboratory strains. Recombinant chimeric viruses, containing the capsid-coding...

  1. Coaching for the SAT: A Summary of the Summaries and an Update. [Reprint.

    ERIC Educational Resources Information Center

    Powers, Donald E.

    1993-01-01

    Several available summaries of research on coaching for the Scholastic Aptitude Test (SAT) are summarized and their principal findings discussed. Some additional studies, that have been completed since these summaries were reported, are considered and linked to the summaries. The four major meta-analyses considered are those of: (1) Messick and…

  2. The Validity of the SAT for Predicting Cumulative Grade Point Average by College Major

    ERIC Educational Resources Information Center

    Shaw, Emily J.; Kobrin, Jennifer L.; Patterson, Brian F.; Mattern, Krista D.

    2011-01-01

    Presented at the Annual Meeting of the American Educational Research Association (AERA) in New Orleans, LA in April 2011. The current study examined the differential validity of the SAT for predicting cumulative GPA through the second-year of college by college major, as well as the differential prediction of cumulative GPA by college major among…

  3. Does Big-Time Success in Football or Basketball Affect SAT Scores?

    ERIC Educational Resources Information Center

    Tucker, Irvin B., III; Amato, Louis

    1993-01-01

    Examines the effects of academics and athletics (including football and basketball variables) on first-year college students' Scholastic Aptitude Test (SAT) scores at U.S. universities engaged in big-time intercollegiate sports. Academic variables rather than athletic success variables determine the level of average first-year students' SAT…

  4. Conquering the SAT: How Parents Can Help Teens Overcome the Pressure and Succeed

    ERIC Educational Resources Information Center

    Johnson, Ned; Eskelsen, Emily Warner

    2006-01-01

    This insightful and practical guide for parents shows how they often undermine rather than encourage their teens' success on one of the most stressful standardized tests--the SAT--and what strategies will remedy the problem. In recent years this test has taken on fearsome proportions, matched only by the growing competition for slots at major…

  5. Propulsion Technology Demonstrator. [Demonstrating Novel CubeSat Technologies in Low Earth Orbit

    NASA Technical Reports Server (NTRS)

    Marmie, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    NASA's Pathfinder Technology Demonstrator (PTD) project will test the operation of a variety of novel CubeSat technologies in low- Earth orbit, providing significant enhancements to the performance of these small and effective spacecraft. Each Pathfinder Technology Demonstrator mission consists of a 6-unit (6U) CubeSat weighing approximately 26 pounds (12 kilograms) and measuring 12 inches x 10 inches x 4 inches (30 centimeters x 25 centimeters x 10 centimeters), comparable in size to a common shoebox. CubeSats are a class of nanosatellites that use a standard size and form factor. The standard Cube- Sat size uses a "one unit" or "1U" measuring 4 inches x 4 inches x 4 inches (10x10x10 centimeters) and is extendable to larger sizes by "stacking" a number of the 1U blocks to form a larger spacecraft. Each PTD spacecraft will also be equipped with deployable solar arrays that provide an average of 44 watts of power while in orbit.

  6. The CarbonSat Earth Explorer 8 candidate mission: Error analysis for carbon dioxide and methane

    NASA Astrophysics Data System (ADS)

    Buchwitz, Michael; Bovensmann, Heinrich; Reuter, Maximilian; Gerilowski, Konstantin; Meijer, Yasjka; Sierk, Bernd; Caron, Jerome; Loescher, Armin; Ingmann, Paul; Burrows, John P.

    2015-04-01

    CarbonSat is one of two candidate missions for ESA's Earth Explorer 8 (EE8) satellite to be launched around 2022. The main goal of CarbonSat is to advance our knowledge on the natural and man-made sources and sinks of the two most important anthropogenic greenhouse gases (GHGs) carbon dioxide (CO2) and methane (CH4) on various temporal and spatial scales (e.g., regional, city and point source scale), as well as related climate feedbacks. CarbonSat will be the first satellite mission optimised to detect emission hot spots of CO2 (e.g., cities, industrialised areas, power plants) and CH4 (e.g., oil and gas fields) and to quantify their emissions. Furthermore, CarbonSat will deliver a number of important by-products such as Vegetation Chlorophyll Fluorescence (VCF, also called Solar Induced Fluorescence (SIF)) at 755 nm. These applications require appropriate retrieval algorithms which are currently being optimized and used for error analysis. The status of this error analysis will be presented based on the latest version of the CO2 and CH4 retrieval algorithm and taking the current instrument specification into account. An overview will be presented focusing on nadir observations over land. Focus will be on specific issues such as errors of the CO2 and CH4 products due to residual polarization related errors and errors related to inhomogeneous ground scenes.

  7. The Impact of the Revamped SAT on Admissions Policies Among Western Land Grant Institutions

    ERIC Educational Resources Information Center

    Choroszy, Melisa N.; Muehlberg, Jessica

    2006-01-01

    The newly revamped Scholastic Aptitude Test (SAT) was administered for the first time in March 2005. Administrators, faculty, and staff in colleges and universities throughout the country were asking the same questions as students: "What was this new score of 2400 and what would it mean for them in terms of admissions, scholarships, and course…

  8. Comparison of SAT Score Trends in Selected Schools Judged to Have Traditional or Experimental Orientations.

    ERIC Educational Resources Information Center

    Jackson, Rex

    A group of highly regarded schools in affluent suburban areas was divided into two groups: those judged to have a traditional orientation and those judged to have a more experimental orientation, in terms of course and program structure. A review of the mean Scholastic Aptitude Test (SAT) from the 1966, 1969, 1973, and 1976 graduating classes from…

  9. River flood events in Thailand and Bangladesh observed by CryoSat

    NASA Astrophysics Data System (ADS)

    Andersen, O. B.; Nielsen, K.; Villadsen, H.; Stenseng, L.; Knudsen, P.

    2014-12-01

    The high along track resolution of the SIRAL altimeter carried on-board CryoSat-2 offers a wide range of unique opportunities for satellite monitoring of inland water level. This study focuses on the ability of CryoSat-2 to detect the effects of flood events such as increased river levels and inundation of land. Here we study two flood events; the Bangladesh flood event of June 2012 and the flooding in Thailand that lasted between July 2011 and January 2012. The flooding in these areas was caused by abnormal monsoonal rainfall and affected millions of people. We process CryoSat-2 level 1b SAR mode data to derive water levels for the areas and compare these levels before, during and after the flooding events. Other parameters such as the backscatter coefficient and pulse peakiness are also considered. To verify the extent of the flooding observed by CryoSat-2 we compare with independent sources such as Landsat images.

  10. FalconSAT-7: Towards Rapidly Deployable Space-Based Surveillance

    NASA Astrophysics Data System (ADS)

    Andersen, G.; McHarg, M.; Asmolova, O.; Dearborn, M.

    2013-09-01

    The USAF Academy Department of Physics is building FalconSAT-7, a membrane solar telescope to be deployed from a 3U CubeSat in LEO. The primary optic is a 0.2m photon sieve - a diffractive element consisting of billions of tiny holes in an otherwise opaque polymer sheet. The membrane, its support structure, secondary optics, two imaging cameras and associated control/recording electronics are all packaged within half the CubeSat volume. Once in space the supporting pantograph structure is deployed to pulling the membrane flat under tension. The telescope will then be steered towards the Sun to gather images at H-alpha for transmission to the ground. Due for launch in 2015, FalconSAT-7 will serve as a pathfinder for future mission in lightweight, high-resolution space-based surveillance. We are currently investigating two possible options optimized for Earth observing and SSA. Our preliminary designs have a 0.3m aperture deployed from a 6-12U satellite. Such a telescope would be capable of providing sub-meter resolution of ground or space-based objects depending on the orbital characteristics.

  11. Unfair Treatment? The Case of Freedle, the SAT, and the Standardization Approach to Differential Item Functioning

    ERIC Educational Resources Information Center

    Santelices, Maria Veronica; Wilson, Mark

    2010-01-01

    In 2003, the "Harvard Educational Review" published a controversial article by Roy Freedle that claimed bias against African American students in the SAT college admissions test. Freedle's work stimulated national media attention and faced an onslaught of criticism from experts at the Educational Testing Service (ETS), the agency responsible for…

  12. A systematic risk management approach employed on the CloudSat project

    NASA Technical Reports Server (NTRS)

    Basilio, R. R.; Plourde, K. S.; Lam, T.

    2000-01-01

    The CloudSat Project has developed a simplified approach for fault tree analysis and probabilistic risk assessment. A system-level fault tree has been constructed to identify credible fault scenarios and failure modes leading up to a potential failure to meet the nominal mission success criteria.

  13. SeaSat-A Satellite Scatterometer (SASS) Validation and Experiment Plan

    NASA Technical Reports Server (NTRS)

    Schroeder, L. C. (Editor)

    1978-01-01

    This plan was generated by the SeaSat-A satellite scatterometer experiment team to define the pre-and post-launch activities necessary to conduct sensor validation and geophysical evaluation. Details included are an instrument and experiment description/performance requirements, success criteria, constraints, mission requirements, data processing requirement and data analysis responsibilities.

  14. Nine Facts about the SAT That Might Surprise You. Statistical Report

    ERIC Educational Resources Information Center

    Letukas, Lynn

    2015-01-01

    The purpose of this document is to identify and dispel rumors that are frequently cited about the SAT. The following is a compilation of nine popular rumors organized into three areas: "Student Demographics," "Test Preparation/Test Prediction," and "Test Utilization."

  15. The Association between SAT Prompt Characteristics, Response Features, and Essay Scores

    ERIC Educational Resources Information Center

    Kobrin, Jennifer L.; Deng, Hui; Shaw, Emily J.

    2011-01-01

    This study investigated the relationship of prompt characteristics and response features with essay scores on the SAT Reasoning Test. A sample of essays was coded on a variety of features regarding their length and content. Analyses included descriptive statistics and computation of effect sizes, correlations between essay features and scores, and…

  16. Point of View--The Sat and the Assault on Literature

    ERIC Educational Resources Information Center

    Ruenzel, David

    2004-01-01

    It was during the early 1990s that the author began to suspect that teenagers were reading less--and less deeply--than they had been 10 and certainly 20 years ago. He found this paradoxical, because it was during the 1990s that SAT scores seemed to soar along with the economy. Students talked about them constantly, like securities traders in a…

  17. Preliminary Validation of the Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Concept

    NASA Technical Reports Server (NTRS)

    Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine

    2004-01-01

    This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.

  18. A University Looks at the College Board's Redesigned SAT

    ERIC Educational Resources Information Center

    Turner, Ronné Patrick

    2014-01-01

    As an institution that receives close to 50,000 applications for the 2,800 spaces for the first-year entering class, Northeastern University took special interest in the College Board's March 5 announcement on the SAT redesign. In this article, associate vice president of enrollment and dean of admissions at Northeastern, Ronné Turner,…

  19. Use of the SAT in Advisement and Placement: What the Research Tells Us

    ERIC Educational Resources Information Center

    Shaw, Emily J.

    2009-01-01

    Presented at the College Board Western Regional Office (WRO) Forum in San Diego in February 2009. This presentation explores SAT test validity and how it can be used to inform both advisement and placement at the national or institution level. Institutional validity can be measured using the Admitted Class Evaluation Service (ACES) which schools…

  20. Texts of Our Institutional Lives: SATs for Writing Placement--A Critique and Counterproposal

    ERIC Educational Resources Information Center

    Isaacs, Emily; Molloy, Sean A.

    2010-01-01

    Focusing on writing placement at a particular university, the authors analyze the limits of SAT tests as a tool in this process. They then describe the writing program's adoption of a supplementary measure: a faculty committee's review of essays by students who may need to be reassigned to a different writing course. They describe how and why a…

  1. A variational analysis of random optimization problems: the example of K-SAT

    NASA Astrophysics Data System (ADS)

    Biroli, Giulio; Monasson, Remi; Weigt, Martin

    2002-03-01

    A variational approach to finite connectivity spin-glass-like models is developed and applied to describe the structure of optimal solutions in random satisfiability problems. Our variational scheme accurately reproduces the known replica symmetric results and also allows for the inclusion of replica symmetry breaking effects. For the 3-SAT problem, we find two transitions as the ratio α of logical clauses per Boolean variables increases. At the first one αs ~= 3.96, a non-trivial organization of the solution space in geometrically separated clusters emerges. The multiplicity of these clusters as well as the typical distances between different solutions are calculated. At the second threshold αc ~= 4.48, satisfying assignments disappear and a finite fraction B0 ~= 0.13 of variables are overconstrained and take the same values in all optimal (though unsatisfying) assignments. These values have to be compared to αc ~= 4.27, B0 ~= 0.4 obtained from numerical experiments on small instances. Within the present variational approach, the SAT-UNSAT transition naturally appears as a mixture of a first and a second order transition. For the mixed 2+p-SAT with p<2/5, the behavior is as expected much simpler: a unique smooth transition from SAT to UNSAT takes place at α_c=1/(1-p).

  2. Foot-and-mouth disease virus serotype SAT 3 in long-horned Ankole calf, Uganda.

    PubMed

    Dhikusooka, Moses Tefula; Tjørnehøj, Kirsten; Ayebazibwe, Chrisostom; Namatovu, Alice; Ruhweza, Simon; Siegismund, Hans Redlef; Wekesa, Sabenzia Nabalayo; Normann, Preben; Belsham, Graham J

    2015-01-01

    After a 16-year interval, foot-and-mouth disease virus serotype SAT 3 was isolated in 2013 from an apparently healthy long-horned Ankole calf that grazed close to buffalo in Uganda. The emergent virus strain is ≈20% different in nucleotide sequence (encoding VP1 [viral protein 1]) from its closest relatives isolated previously from buffalo in Uganda. PMID:25531186

  3. Solving the SAT problem using a DNA computing algorithm based on ligase chain reaction.

    PubMed

    Wang, Xiaolong; Bao, Zhenmin; Hu, Jingjie; Wang, Shi; Zhan, Aibin

    2008-01-01

    A new DNA computing algorithm based on a ligase chain reaction is demonstrated to solve an SAT problem. The proposed DNA algorithm can solve an n-variable m-clause SAT problem in m steps and the computation time required is O (3m+n). Instead of generating the full-solution DNA library, we start with an empty test tube and then generate solutions that partially satisfy the SAT formula. These partial solutions are then extended step by step by the ligation of new variables using Taq DNA ligase. Correct strands are amplified and false strands are pruned by a ligase chain reaction (LCR) as soon as they fail to satisfy the conditions. If we score and sort the clauses, we can use this algorithm to markedly reduce the number of DNA strands required throughout the computing process. In a computer simulation, the maximum number of DNA strands required was 2(0.48n) when n=50, and the exponent ratio varied inversely with the number of variables n and the clause/variable ratio m/n. This algorithm is highly space-efficient and error-tolerant compared to conventional brute-force searching, and thus can be scaled-up to solve large and hard SAT problems. PMID:17904730

  4. Foot-and-Mouth Disease Virus Serotype SAT 3 in Long-Horned Ankole Calf, Uganda

    PubMed Central

    Dhikusooka, Moses Tefula; Tjørnehøj, Kirsten; Ayebazibwe, Chrisostom; Namatovu, Alice; Ruhweza, Simon; Siegismund, Hans Redlef; Wekesa, Sabenzia Nabalayo; Normann, Preben

    2015-01-01

    After a 16-year interval, foot-and-mouth disease virus serotype SAT 3 was isolated in 2013 from an apparently healthy long-horned Ankole calf that grazed close to buffalo in Uganda. The emergent virus strain is ≈20% different in nucleotide sequence (encoding VP1 [viral protein 1]) from its closest relatives isolated previously from buffalo in Uganda. PMID:25531186

  5. Evaluation of different adjuvants for foot-and-mouth disease vaccine containing all the SAT serotypes.

    PubMed

    Cloete, M; Dungu, B; Van Staden, L I; Ismail-Cassim, N; Vosloo, W

    2008-03-01

    Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals that is primarily controlled by vaccination of susceptible animals and movement restrictions for animals and animal-derived products in South Africa. Vaccination using aluminium hydroxide gel-saponin (AS) adjuvanted vaccines containing the South African Territories (SAT) serotypes has been shown to be effective both in ensuring that disease does not spread from the endemic to the free zone and in controlling outbreaks in the free zone. Various vaccine formulations containing antigens derived from the SAT serotypes were tested in cattle that were challenged 1 year later. Both the AS and ISA 206B vaccines adjuvanted with saponin protected cattle against virulent virus challenge. The oil-based ISA 206B-adjuvanted vaccine with and without stimulators was evaluated in a field trial and both elicited antibody responses that lasted for 1 year. Furthermore, the ISA 206 adjuvanted FMD vaccine protected groups of cattle against homologous virus challenge at very low payloads, while pigs vaccinated with an emergency ISA 206B-based FMD vaccine containing the SAT 1 vaccine strains were protected against the heterologous SAT 1 outbreak strain. PMID:18575060

  6. SAT-1 -1415T/C polymorphism and susceptibility to schizophrenia.

    PubMed

    Bermudo-Soriano, Carlos Riaza; Vaquero-Lorenzo, Concepcion; Diaz-Hernandez, Montserrat; Perez-Rodriguez, M Mercedes; Fernandez-Piqueras, Jose; Saiz-Ruiz, Jeronimo; Baca-Garcia, Enrique

    2009-03-17

    Patients suffering from psychosis show increased blood and fibroblast total polyamine levels. Spermidine/spermine N1-acetyltransferase (SSAT-1) and its coding gene (SAT-1) are the main factors regulating polyamine catabolism. The aim of the present study was to examine the association between the SAT-1 -1415T/C single nucleotide polymorphism (SNP) and schizophrenia. A case-control design was used in order to compare the genotypes for the SNP between schizophrenia patients (n=180, 83 females and 97 males), other non-psychotic psychiatric patients (n=413, 256 females and 157 males), and healthy controls (n=251, 101 females and 150 males). No significant differences in the distribution of the genotypes of the SAT-1 -1415T/C SNP were found groups among groups. We failed to demonstrate a significant association between the SAT-1 -1415T/C SNP and schizophrenia, but a mild association between allele C and psychopathology was found in the female group. PMID:19162121

  7. Using Additive Manufacturing to Print a CubeSat Propulsion System

    NASA Technical Reports Server (NTRS)

    Marshall, William M.; Zemba, Michael; Shemelya, Corey; Wicker, Ryan; Espalin, David; MacDonald, Eric; Keif, Craig; Kwas, Andrew

    2015-01-01

    Small satellites, such as CubeSats, are increasingly being called upon to perform missions traditionally ascribed to larger satellite systems. However, the market of components and hardware for small satellites, particularly CubeSats, still falls short of providing the necessary capabilities required by ever increasing mission demands. One way to overcome this shortfall is to develop the ability to customize every build. By utilizing fabrication methods such as additive manufacturing, mission specific capabilities can be built into a system, or into the structure, that commercial off-the-shelf components may not be able to provide. A partnership between the University of Texas at El Paso, COSMIAC at the University of New Mexico, Northrop Grumman, and the NASA Glenn Research Center is looking into using additive manufacturing techniques to build a complete CubeSat, under the Small Spacecraft Technology Program. The W. M. Keck Center at the University of Texas at El Paso has previously demonstrated the ability to embed electronics and wires into the addtively manufactured structures. Using this technique, features such as antennas and propulsion systems can be included into the CubeSat structural body. Of interest to this paper, the team is investigating the ability to take a commercial micro pulsed plasma thruster and embed it into the printing process. Tests demonstrating the dielectric strength of the printed material and proof-of-concept demonstration of the printed thruster will be shown.

  8. New Mexico Enhanced ACT and SAT Results. School Year 1992-1993.

    ERIC Educational Resources Information Center

    Cavatta, M. Louise

    Students in New Mexico may take either the American College Test Assessment (ACT) or the Scholastic Aptitude Test (SAT), although the ACT is most often used in New Mexico. Results from both examinations are presented in this report, based on those students who were expected to graduate in 1993 and who had expressed an interest in attending…

  9. Why Some Students Perform Well and Others Perform Poorly on SAT Math Items.

    ERIC Educational Resources Information Center

    Byrnes, James P.; Takahira, Sayuri

    1994-01-01

    Results from 40 high school students on the mathematics subtest of the Scholastic Aptitude Test (SAT) support the prediction that successful students would have more prior knowledge and would be better at defining problems, assembling strategies, and avoiding computational errors. Results are discussed in terms of a cognitive processing model.…

  10. Gaps in College Readiness: ACT and SAT Differences by Ethnicity across 10 School Years

    ERIC Educational Resources Information Center

    Harvey, Donzel Wayne

    2013-01-01

    Purpose: The purpose of this study was to examine the college-readiness rates of Black, Hispanic, White, and Asian graduates of public secondary schools in Texas using archival data from the Texas Education Agency Academic Excellence Indicator System. Data examined were the average ACT and SAT scores for the past 10 school years (i.e., 2001-2002…

  11. Could There Be a Medical Basis for the Declining SAT Scores?

    ERIC Educational Resources Information Center

    Arnold, Charles B.

    The scores of the Scholastic Aptitude Test (SAT) have been declining since 1963. While this decline has occurred, scores on achievement tests administered to students in grades 3 to 11 have been stable. An alalysis of the medical and epidemiological literature was conducted to determine whether there could be a health factor that might have caused…

  12. The Role of Socioeconomic Status in SAT-Freshman Grade Relationships across Gender and Racial Subgroups

    ERIC Educational Resources Information Center

    Higdem, Jana L.; Kostal, Jack W.; Kuncel, Nathan R.; Sackett, Paul R.; Shen, Winny; Beatty, Adam S.; Kiger, Thomas B.

    2016-01-01

    Recent research has shown that admissions tests retain the vast majority of their predictive power after controlling for socioeconomic status (SES), and that SES provides only a slight increment over SAT and high school grades (high school grade point average [HSGPA]) in predicting academic performance. To address the possibility that these…

  13. CubeSat-Scale UV and RF Remote Sensing Instruments for Upper Atmosphere Research

    NASA Astrophysics Data System (ADS)

    Doe, R. A.; Noto, J.; Crowley, G.; Bust, G. S.

    2012-12-01

    Increasing opportunities for in-situ measurements of atmospheric state variables (composition, temperatures, drifts) from CubeSats such as the USAF SENSE and the University of Michigan CADRE missions will soon establish a rich set of thermosphere data not available since the era of DE-2. Of particular significance is the parallel development of optical and RF remote sensing instruments purpose built for the CubeSat standard. These sensors are have been flight qualified and are available for inclusion in future CubeSat payloads.This presentation will present an overview of two such remote sensing instruments. The radio aurora explorer (RAX) is an on-orbit UHF bistatic radar that characterizes ionospheric turbulence illuminated by high power ground-based transmitters. The CubeSat Tiny Ionospheric Photometer (CTIP) acquires naturally-occurring 135.6-nm radiance measurements as a proxy for line-of-sight ionospheric density with applications that include both nadir and scanning orientation. We will also discuss RAX and CTIP mission design, highlight recent mission discoveries, and summarize future sensor enhancements.

  14. Lipometer subcutaneous adipose tissue topography (SAT-Top) reflects serum leptin levels varying in circadian rhythms

    NASA Astrophysics Data System (ADS)

    Moeller, Reinhard; Tafeit, Erwin; Sudi, Karl; Vrecko, Karoline; Horejsi, Renate; Hinghofer-Szalkay, Helmut G.; Reibnegger, Gilbert

    1998-05-01

    Recent advances in obesity research have shown that the product of the ob-gene named leptin is related to total body fast mass in humans. There is, however, a debate if leptin levels are pulsatile and linked to body fat distribution. In this study we therefore investigated the subcutaneous adipose tissue topography (SAT-Top) measured by means of the newly developed device Lipometer and leptin levels during a 24 hours beginning at 0715am ending the same time in the next day. Blood samples for measurement of leptin were taken every 3 hours in a male subject. Measurements of SAT-Top were performed at 15 body sites from neck to calf at the left and right body site at the same time interval. We observed an almost symmetrically reaction of the left and right body site with a maximum of the mean value of all body sites in the evening at 0715pm. There was a negative correlation between serum leptin levels and SAT-Top using the set of certain body sites (R2 equals 0.80, p equals 0.01). If these combination of body sites is inversed and set against serum leptin levels, both curves show almost identical shape and time dependence. We conclude that SAT-Top by means of Lipometer is changed in a short time and related to leptin levels in the investigated male subject.

  15. Determinants of Undergraduate GPAs: SAT Scores, High-School GPA and High-School Rank

    ERIC Educational Resources Information Center

    Cohn, Elchanan; Cohn, Sharon; Balch, Donald C.; Bradley, James, Jr.

    2004-01-01

    The primary purpose of the study is to assess the degree to which SAT scores, high-school GPA (HSGPA) and class rank predict success in college. Data collected from students enrolled in several sections of Principles of Economics at the University of South Carolina in 2000 and 2001 are used to study the relation between college GPA (the dependent…

  16. Cryogenic On-Orbit Liquid Depot Storage, Acquisition, and Transfer satellite (COLD-SAT) feasibility study

    NASA Technical Reports Server (NTRS)

    Bailey, William J.; Weiner, Stephen P.; Beekman, Douglas H.; Dennis, Mark F.; Martin, Timothy A.

    1990-01-01

    The Cryogenic On-Orbit Liquid Depot Storage, Acquisition, and Transfer Satellite (COLD-SAT) is an experimental spacecraft launched from an expendable launch vehicle which is designed to investigate the systems and technologies required for efficient, effective, and reliable management of cryogenic fluid in the reduced gravity space environment. The COLD-SAT program will provide the necessary data base and provide low-g proving of fluid and thermal models of cryogenic storage, transfer, and resupply concepts and processes. A conceptual approach was developed and an overview of the results of the 24 month COLD-SAT Phase A feasibility is described which includes: (1) a definition of the technology needs and the accompanying experimental 3 month baseline mission; (2) a description of the experiment subsystem, major features and rationale for satisfaction of primary and secondary experiment requirements using liquid hydrogen as the test fluid; and (3) a presentation of the conceptual design of the COLD-SAT spacecraft subsystems which support the on-orbit experiment with emphasis on areas of greatest challenge.

  17. Georgia Is All Business as It Moves to Improve State's Showing on SAT

    ERIC Educational Resources Information Center

    Jacobson, Linda

    2005-01-01

    Students are not the only ones in Georgia fretting over scores from the recent SAT exams. More than perhaps any other state, Georgia has linked its reputation as a place to live, send children to school, and do business to the state's performance on the college-entrance test. Since Governor Sonny Perdue launched a statewide effort to raise those…

  18. A Potential Operational CryoSat Follow-on Mission Concept and Design

    NASA Astrophysics Data System (ADS)

    Cullen, R.

    2015-12-01

    CryoSat was a planned as a 3 year mission with clear mission objectives to allow the assessment rates of change of thickness in the land and marine ice fields with reduced uncertainties with relation to other non-dedicated missions. Although CryoSat suffered a launch failure in Oct 2005, the mission was recovered with a launch in April 2010 of CryoSat-2. The nominal mission has now been completed, all mission requirements have been fulfilled and CryoSat has been shown to be most successful as a dedicated polar ice sheet measurement system demonstrated by nearly 200 peer reviewed publications within the first four years of launch. Following the completion of the nominal mission in Oct 2013 the platform was shown to be in good health and with a scientific backing provided by the ESA Earth Science Advisory Committee (ESAC) the mission has been extended until Feb 2017 by the ESA Programme Board for Earth Observation. Though not designed to provide data for science and operational services beyond its original mission requirements, a number of services have been developed for exploitation and these are expected to increase over the next few years. Services cover a number of aspects of land and marine ice fields in addition to complementary activities covering glacial monitoring, inland water in addition to coastal and open ocean surface topography science that CryoSat has demonstrated world leading advances with. This paper will present the overall concept for a potential low-cost follow-on to the CryoSat mission with the objective to provide both continuity of the existing CryoSat based data sets, i.e., longer term science and operational services that cannot be provided by the existing Copernicus complement of satellites. This is, in part, due to the high inclination (92°) drifting orbit and state of the art Synthetic Aperture Interferometer Radar Altimeter (SIRAL). In addition, further improvements in performance are expected by use of the instrument timing and

  19. Interplanetary CubeSats system for space weather evaluations and technology demonstration

    NASA Astrophysics Data System (ADS)

    Viscio, Maria Antonietta; Viola, Nicole; Corpino, Sabrina; Stesina, Fabrizio; Fineschi, Silvano; Fumenti, Federico; Circi, Christian

    2014-11-01

    The paper deals with the mission analysis and conceptual design of an interplanetary 6U CubeSats system to be implemented in the L1 Earth-Sun Lagrangian Point mission for solar observation and in-situ space weather measurements. Interplanetary CubeSats could be an interesting alternative to big missions, to fulfill both scientific and technological tasks in deep space, as proved by the growing interest in this kind of application in the scientific community and most of all at NASA. Such systems allow less costly missions, due to their reduced sizes and volumes, and consequently less demanding launches requirements. The CubeSats mission presented in this paper is aimed at supporting measurements of space weather. The mission envisages the deployment of a 6U CubeSats system in the L1 Earth-Sun Lagrangian Point, where solar observations for in situ measurements of space weather to provide additional warning time to Earth can be carried out. The proposed mission is also intended as a technology validation mission, giving the chance to test advanced technologies, such as telecommunications and solar sails, envisaged as propulsion system. Furthermore, traveling outside the Van Allen belts, the 6U CubeSats system gives the opportunity to further investigate the space radiation environment: radiation dosimeters and advanced materials are envisaged to be implemented, in order to test their response to the harsh space environment, even in view of future implementation on other spacecrafts (e.g. manned spacecrafts). The main issue related to CubeSats is how to fit big science within a small package - namely power, mass, volume, and data limitations. One of the objectives of the work is therefore to identify and size the required subsystems and equipment, needed to accomplish specific mission objectives, and to investigate the most suitable configuration, in order to be compatible with the typical CubeSats (multi units) standards. The work has been developed as collaboration

  20. Improved Oceanographic Measurements with CryoSat SAR Altimetry: Application to the Coastal Zone and Arctic

    NASA Astrophysics Data System (ADS)

    Cotton, David; Nilo Garcia, Pablo; Cancet, Mathilde; Andersen, Ole; Stenseng, Lars; Martin, Francisco; Cipollini, Paolo; Benveniste, Jérôme; Restano, Marco; Ambrósio, Américo

    2016-04-01

    The ESA CryoSat mission is the first space mission to carry a radar altimeter that can operate in Synthetic Aperture Radar "SAR" (or delay-Doppler) and interferometric SAR (SARin) modes. Studies on CryoSat data have analysed and confirmed the improved ocean measuring capability offered by SAR mode altimetry, through increased resolution and precision in sea surface height and wave height measurements, and have also added significantly to our understanding of the issues around the processing and interpretation of SAR altimeter echoes. We present work in four themes, building on work initiated in the CryoSat Plus for Oceans project (CP4O), each investigating different aspects of the opportunities offered by this new technology. The first two studies address the coastal zone, a critical region for providing a link between open-ocean and shelf sea measurements with those from coastal in-situ measurements, in particular tide gauges. Although much has been achieved in recent years through the Coastal Altimetry community, (http://www.coastalt.eu/community) there is a limit to the capabilities of pulse-limited altimetry which often leaves an un-measured "white strip" right at the coastline. Firstly, a thorough analysis was made of the performance of "SAR" altimeter data (delay-Doppler processed) in the coastal zone. This quantified the performance, confirming the significant improvement over "conventional" pulse-limited altimetry. In the second study a processing scheme was developed with CryoSat SARin mode data to enable the retrieval of valid oceanographic measurements in coastal areas with complex topography. Thanks to further development of the algorithms, a new approach was achieved that can also be applied to SAR and conventional altimetry data (e.g., Sentinel-3, Jason series, EnviSat). The third part of the project developed and evaluated improvements to the SAMOSA altimeter re-tracker that is implemented in the Sentinel-3 processing chain. The modifications to the

  1. Melting of H_2SO_4\\cdot4H_2O Particles upon Cooling: Implications for Polar Stratospheric Clouds

    NASA Astrophysics Data System (ADS)

    Koop, Thomas; Carslaw, Kenneth S.

    1996-06-01

    Polar stratospheric clouds (PSCs) are important for the chemical activation of chlorine compounds and subsequent ozone depletion. Solid PSCs can form on sulfuric acid tetrahydrate (SAT) (H_2SO_4\\cdot4H_2O) nuclei, but recent laboratory experiments have shown that PSC nucleation on SAT is strongly hindered. A PSC formation mechanism is proposed in which SAT particles melt upon cooling in the presence of HNO_3 to form liquid HNO_3-H_2SO_4\\cdotH_2O droplets 2 to 3 kelvin above the ice frost point. This mechanism offers a PSC formation temperature that is defined by the ambient conditions and sets a temperature limit below which PSCs should form.

  2. A 6U CubeSat Constellation for Atmospheric Temperature and Humidity Sounding

    NASA Technical Reports Server (NTRS)

    Padmanabhan, Sharmila; Brown, Shannon; Kangaslahti, Pekka; Cofield, Richard; Russell, Damon; Stachnik, Robert; Steinkraus, Joel; Lim, Boon

    2013-01-01

    We are currently developing a 118/183 GHz sensor that will enable observations of temperature and precipitation profiles over land and ocean. The 118/183 GHz system is well suited for a CubeSat deployment as 10cm antenna aperture provides sufficiently small footprint sizes (is approx. 25km). This project will enable low cost, compact radiometer instrumentation at 118 and 183 GHz that would fit in a 6U CubeSat with the objective of mass-producing this design to enable a suite of small satellites to image the key geophysical parameters that are needed to improve prediction of extreme weather events. We will take advantage of past and current technology developments at JPL viz. HAMSR (High Altitude Microwave Scanning Radiometer), Advanced Component Technology (ACT'08) to enable low-mass and low-power high frequency airborne radiometers. The 35 nm InP enabling technology provides significant reduction in power consumption (Low Noise Amplifier + Mixer Block consumes 24 mW). In this paper, we will describe the design and implementation of the 118 GHz temperature sounder and 183 GHz humidity sounder instrument on the 6U CubeSat. In addition, a summary of radiometer calibration and retrieval techniques of the temperature and humidity will be discussed. The successful demonstration of this instrument on the 6U CubeSat would pave the way for the development of a constellation consisting of suite of these instruments. The proposed constellation of these 6U CubeSat radiometers would allow sampling of tropospheric temperature and humidity with fine temporal (on the order of minutes) and spatial resolution (is approx. 25 km).

  3. An improved wet tropospheric correction for CryoSat-2 over open and coastal ocean

    NASA Astrophysics Data System (ADS)

    Joana Fernandes, M.; Lázaro, Clara; Nunes, Alexandra L.; Pires, Nelson; Dinardo, Salvatore; Benveniste, Jérôme

    2014-05-01

    In the scope of the CryoSat Plus for Oceans (CP4O) project, encouraged by the European Space Agency, a data combination (DComb) algorithm has been developed for the computation of the wet tropospheric correction (WTC) for CryoSat-2, which does not possess an onboard microwave radiometer (MWR), thus relying on a model-based WTC provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). This WTC is based on the objective analysis of all available wet path delay data sources (e.g. from scanning imaging MWR (SI MWR) on board remote sensing satellites, those derived from Global Navigation Satellite Systems (GNSS) measurements at coastal stations and from an atmospheric model such as the ECMWF ReAnalysis (ERA) Interim. This presentation gives a brief description of the DComb algorithm and its application to CryoSat-2. The algorithm was first applied to Jason-2 and compared with the correction from the Jason-2 advanced microwave radiometer (AMR) present on the version D of the Geophysical Data Records (GDR-D), known to be a well calibrated and accurate correction, with improved performance in coastal regions. These results show that for epochs and locations for which SI-MWR measurements are available, the DComb WTC is very similar to that of AMR, evidencing that the SI-MWR water vapour products, previously calibrated with respect to AMR, are an extremely valuable data set for the estimation of the WTC for any altimeter mission, including those which possess an onboard MWR. For both Jason-2 and CryoSat-2 the new correction was validated through analysis of sea level anomaly variance at crossovers, function of distance from the coast and latitude. The influence of the GNSS-derived wet path delays in the coastal regions, of major importance for the full exploitation of CryoSat-2 data, in particular those acquired in the Synthetic Aperture Radar (SAR) mode, is also shown.

  4. Identifying false rain in satellite precipitation products using CloudSat and MODIS

    NASA Astrophysics Data System (ADS)

    Nasrollahi, N.; Hsu, K.; Sorooshian, S.

    2012-12-01

    Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on board NASA Earth Observing System Aqua and Terra platform with 36 spectral bands provides valuable information about cloud microphysical characteristics. Additionally, CloudSat, selected as a NASA Earth Sciences Systems Pathfinder (ESSP) satellite mission, is designed to measure vertical structure of clouds. The CloudSat radar flies in formation with Aqua with only an average of 60 second delay. In this study, the application of MODIS multispectral images and CloudSat Level 2-C Precipitation Column Algorithm in false rain identification is investigated. Using a machine learning technique, the presence of precipitation will be assigned to textural and spectral features of clouds observed by the MODIS satellite, whenever CloudSat surface rainfall retrieval is available. This information for different regions and seasons create a training data set. The training database will then be used as a reference to find if any pixel in the MODIS retrieval window is falsely identified as rainy pixel for the times that CloudSat data is not available. The input to the Artificial Neural Networks (ANN) model is a combination of 8 MODIS visible, water vapor and infrared channels. The performance of model with combination of different MODIS channels is estimated. The results of ANN model are used to filter out false rainy pixels from satellite precipitation estimates (e.g. PERSIANN). The outcome of the new corrected precipitation data is compared to ground based radar measurements (Stage IV radar data). The results show a 64 percent reduction in false rain in PERSIANN satellite data for 100 cases investigated in summer 2008 and 24 percent false rain reduction in more than 50 cases studied in winter 2010.

  5. Electrospray Thrusters for Attitude Control of a 1-U CubeSat

    NASA Astrophysics Data System (ADS)

    Timilsina, Navin

    With a rapid increase in the interest in use of nanosatellites in the past decade, finding a precise and low-power-consuming attitude control system for these satellites has been a real challenge. In this thesis, it is intended to design and test an electrospray thruster system that could perform the attitude control of a 1-unit CubeSat. Firstly, an experimental setup is built to calculate the conductivity of different liquids that could be used as propellants for the CubeSat. Secondly, a Time-Of-Flight experiment is performed to find out the thrust and specific impulse given by these liquids and hence selecting the optimum propellant. On the other hand, a colloidal thruster system for a 1-U CubeSat is designed in Solidworks and fabricated using Lathe and CNC Milling Machine. Afterwards, passive propellant feeding is tested in this thruster system. Finally, the electronic circuit and wireless control system necessary to remotely control the CubeSat is designed and the final testing is performed. Among the propellants studied, Ethyl ammonium nitrate (EAN) was selected as the best propellant for the CubeSat. Theoretical design and fabrication of the thruster system was performed successfully and so was the passive propellant feeding test. The satellite was assembled for the final experiment but unfortunately the microcontroller broke down during the first test and no promising results were found out. However, after proving that one thruster works with passive feeding, it could be said that the ACS testing would have worked if we had performed vacuum compatibility tests for other components beforehand.

  6. MarsCAT: Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster

    NASA Astrophysics Data System (ADS)

    Bering, Edgar Andrew; Pinsky, Lawrence S.; Li, Liming; Jackson, David; Chen, Ji; Reed, Helen; Moldwin, Mark; Kasper, Justin; Sheehan, J. P.; Forbes, James Richard; Heine, Thomas; Case, Anthony; Stevens, Michael; Sibeck, David G.

    2015-11-01

    The MarsCAT (Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster) Mission is a two 6U CubeSat mission to study the ionosphere of Mars proposed for the NASA SIMPLeX opportunity. The mission will investigate the plasma and magnetic structure of the Martian ionosphere, including transient plasma structures, magnetic field structure and dynamics, and energetic particle activity. The transit plan calls for a piggy back ride with Mars 2020 using a CAT burn for MOI, the first demonstration of CubeSat propulsion for interplanetary travel. MarsCAT will make correlated multipoint studies of the ionosphere and magnetic field of Mars. Specifically, the two spacecraft will make in situ observations of the plasma density, temperature, and convection in the ionosphere of Mars. They will also make total electron content measurements along the line of sight between the two spacecraft and simultaneous 3-axis local magnetic field measurements in two locations. Additionally, MarsCAT will demonstrate the performance of new CubeSat telemetry antennas designed at the University of Houston that are designed to be low profile, rugged, and with a higher gain than conventional monopole (whip) antennas. The two MarsCAT CubeSats will have five science instruments: a 3-axis DC magnetometer, adouble-Langmuir probe, a Faraday cup, a solid state energetic particle detector (Science Enhancement Option), and interspacecraft total electron content radio occulation experiment. The MarsCAT spacecraft will be solar powered and equipped with a CAT thruster that can provide up to 4.8 km/s of delta-V, which is sufficient to achieve Mars orbit using the Mars 2020 piggyback. They have an active attitude control system, using a sun sensor and flight-proven star tracker for determination, and momentum wheels for 3-axis attitude control.

  7. Micro Cathode Arc Thruster for PhoneSat: Development and Potential Applications

    NASA Technical Reports Server (NTRS)

    Gazulla, Oriol Tintore; Perez, Andres Dono; Agasid, Elwood; Uribe, Eddie; Trinh, Greenfield; Keidar, Michael; Teel, George; Haque, Samudra; Lukas, Joseph; Salas, Alberto Guillen; Wolfe, Jasper; Attai, Watson; Oyadomari, Ken; Priscal, Cedric; Schimmin, Rogan

    2014-01-01

    NASA Ames Research Center and the George Washington University are developing an electric propulsion subsystem that will be integrated into the PhoneSat bus. Experimental tests have shown a reliable performance by firing three different thrusters at various frequencies in vacuum conditions. The interface consists of a microcontroller that sends a trigger pulse to the Pulsed Plasma Unit that is responsible for the thruster operation. A Smartphone is utilized as the main user interface for the selection of commands that control the entire system. The propellant, which is the cathode itself, is a solid cylinder made of Titanium. This simplicity in the design avoids miniaturization and manufacturing problems. The characteristics of this thruster allow an array of µCATs to perform attitude control and orbital correction maneuvers that will open the door for the implementation of an extensive collection of new mission concepts and space applications for CubeSats. NASA Ames is currently working on the integration of the system to fit the thrusters and the PPU inside a 1.5U CubeSat together with the PhoneSat bus. This satellite is intended to be deployed from the ISS in 2015 and test the functionality of the thrusters by spinning the satellite around its long axis and measure the rotational speed with the phone gyros. This test flight will raise the TRL of the propulsion system from 5 to 7 and will be a first test for further CubeSats with propulsion systems, a key subsystem for long duration or interplanetary small satellite missions.

  8. Feasibility of assessing the needs of stroke patients after six months using the GM-SAT

    PubMed Central

    Boaden, Ruth; Bamford, David; Tyrrell, Pippa J

    2013-01-01

    Objective: To investigate the feasibility of administering the Greater Manchester Stroke Assessment Tool (GM-SAT), a structured evidence-based needs assessment tool, in a community setting and its acceptability to stroke patients and their carers. Setting: Community stroke services. Subjects: One hundred and thirty-seven stroke patients at six months post hospital discharge with no communication or cognitive difficulties residing in their own homes. Intervention: Patients’ needs were assessed by information, advice and support (IAS) coordinators from the UK Stroke Association using the GM-SAT. Main measures: Number and nature of unmet needs identified and actions required to address these; patient/carer feedback; and IAS coordinator feedback. Results: The mean number of unmet needs identified was 3 (min 0, max 14; SD 2.5). The most frequently identified unmet needs related to fatigue (34.3%), memory, concentration and attention (25.5%), secondary prevention non-lifestyle (21.9%) and depression (19.0%). It was found that 50.4% of unmet needs could be addressed through the provision of information and advice. Patients/carers found the assessment process valuable and IAS coordinators found the GM-SAT easy to use. Conclusions: Results demonstrate that the GM-SAT is feasible to administer in the community using IAS coordinators and is acceptable to patients and their carers, as well as staff undertaking the assessments. Further research is needed to determine whether the application of the GM-SAT at six months improves outcomes for patients. PMID:22952306

  9. MarsCAT: Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster

    NASA Astrophysics Data System (ADS)

    Bering, E. A., III; Pinsky, L.; Li, L.; Jackson, D. R.; Chen, J.; Reed, H.; Moldwin, M.; Kasper, J. C.; Sheehan, J. P.; Forbes, J.; Heine, T.; Case, A. W.; Stevens, M. L.; Sibeck, D. G.

    2015-12-01

    The MarsCAT (Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster) Mission is a two 6U CubeSat mission to study the ionosphere of Mars proposed for the NASA SIMPLeX opportunity. The mission will investigate the plasma and magnetic structure of the Martian ionosphere, including transient plasma structures, magnetic field structure and dynamics, and energetic particle activity. The transit plan calls for a piggy back ride with Mars 2020 using a CAT burn for MOI, the first demonstration of CubeSat propulsion for interplanetary travel. MarsCAT will make correlated multipoint studies of the ionosphere and magnetic field of Mars. Specifically, the two spacecraft will make in situ observations of the plasma density, temperature, and convection in the ionosphere of Mars. They will also make total electron content measurements along the line of sight between the two spacecraft and simultaneous 3-axis local magnetic field measurements in two locations. Additionally, MarsCAT will demonstrate the performance of new CubeSat telemetry antennas designed at the University of Houston that are designed to be low profile, rugged, and with a higher gain than conventional monopole (whip) antennas. The two MarsCAT CubeSats will have five science instruments: a 3-axis DC magnetometer, adouble-Langmuir probe, a Faraday cup, a solid state energetic particle detector (Science Enhancement Option), and interspacecraft total electron content radio occulation experiment. The MarsCAT spacecraft will be solar powered and equipped with a CAT thruster that can provide up to 4.8 km/s of delta-V, which is sufficient to achieve Mars orbit using the Mars 2020 piggyback. They have an active attitude control system, using a sun sensor and flight-proven star tracker for determination, and momentum wheels for 3-axis attitude control.

  10. The effect of the BalloonSat project on middle and high school students' attitude toward science

    NASA Astrophysics Data System (ADS)

    Verhage, L. Paul

    This study measured the effect of completing a BalloonSat project on student attitude toward science. Seven categories of student attitudes toward science were measured using the Test of Science Relate Attitudes survey (TOSRA). The research anticipated that the BalloonSat project would have similar effects on student attitudes as found in robotics projects, like FIRST. The researcher also investigated whether gender moderated the effects of the BalloonSat project. This study enrolled 138 students from three states and one Canadian province. Students were free to select membership in either the treatment group or the control group. Student attitude toward science was measured prior to the start of the study and at its completion. Mean scores for the control and treatment group were then compared using an analysis of covariance. The effect of the BalloonSat project only affected one attitude toward science, Leisure Interest in Science. The study did not find gender was a factor in the effects of the BalloonSat project. This study is the first study of the BalloonSat project on grade 7--10 students and provides some evidence that a BalloonSat project can impact middle and high school attitude toward science.

  11. Design, Development, Implementation, and On-orbit Performance of the Dynamic Ionosphere CubeSat Experiment Mission

    NASA Astrophysics Data System (ADS)

    Fish, C. S.; Swenson, C. M.; Crowley, G.; Barjatya, A.; Neilsen, T.; Gunther, J.; Azeem, I.; Pilinski, M.; Wilder, R.; Allen, D.; Anderson, M.; Bingham, B.; Bradford, K.; Burr, S.; Burt, R.; Byers, B.; Cook, J.; Davis, K.; Frazier, C.; Grover, S.; Hansen, G.; Jensen, S.; LeBaron, R.; Martineau, J.; Miller, J.; Nelsen, J.; Nelson, W.; Patterson, P.; Stromberg, E.; Tran, J.; Wassom, S.; Weston, C.; Whiteley, M.; Young, Q.; Petersen, J.; Schaire, S.; Davis, C. R.; Bokaie, M.; Fullmer, R.; Baktur, R.; Sojka, J.; Cousins, M.

    2014-05-01

    Funded by the NSF CubeSat and NASA ELaNa programs, the Dynamic Ionosphere CubeSat Experiment (DICE) mission consists of two 1.5U CubeSats which were launched into an eccentric low Earth orbit on October 28, 2011. Each identical spacecraft carries two Langmuir probes to measure ionospheric in-situ plasma densities, electric field probes to measure in-situ DC and AC electric fields, and a science grade magnetometer to measure in-situ DC and AC magnetic fields. Given the tight integration of these multiple sensors with the CubeSat platforms, each of the DICE spacecraft is effectively a "sensor-sat" capable of comprehensive ionospheric diagnostics. The use of two identical sensor-sats at slightly different orbiting velocities in nearly identical orbits permits the de-convolution of spatial and temporal ambiguities in the observations of the ionosphere from a moving platform. In addition to demonstrating nanosat-based constellation science, the DICE mission is advancing a number of groundbreaking CubeSat technologies including miniaturized mechanisms and high-speed downlink communications.

  12. Sat, the Secreted Autotransporter Toxin of Uropathogenic Escherichia coli, Is a Vacuolating Cytotoxin for Bladder and Kidney Epithelial Cells

    PubMed Central

    Guyer, Debra M.; Radulovic, Suzana; Jones, Faye-Ellen; Mobley, Harry L. T.

    2002-01-01

    The secreted autotransporter toxin (Sat) of uropathogenic Escherichia coli exhibits cytopathic activity upon incubation with HEp-2 cells. We further investigated the effects of Sat on cell lines more relevant to the urinary tract, namely, those derived from bladder and kidney epithelium. Sat elicited elongation of cells and apparent loosening of cellular junctions upon incubation with Vero kidney cells. Additionally, incubation with Sat triggered significant vacuolation within the cytoplasm of both human bladder (CRL-1749) and kidney (CRL-1573) cell lines. This activity has been associated with only a few other known toxins. Following transurethral infection of CBA mice with a sat mutant, no reduction of CFU in urine, bladder, or kidney tissue was seen compared to that in mice infected with wild-type E. coli CFT073. However, significant histological changes were observed within the kidneys of mice infected with wild-type E. coli CFT073, including dissolution of the glomerular membrane and vacuolation of proximal tubule cells. Such damage was not observed in kidney sections of mice infected with a Sat-deficient mutant. These results indicate that Sat, a vacuolating cytotoxin expressed by uropathogenic E. coli CFT073, elicits defined damage to kidney epithelium during upper urinary tract infection and thus contributes to pathogenesis of urinary tract infection. PMID:12117966

  13. Amplitude-phase characteristics of SAT annual cycle in Asia: tendencies of change derived from observations and reanalyses and from numerical experiments with IAP RAS CM

    NASA Astrophysics Data System (ADS)

    Eliseev, Alexey V.; Mokhov, Igor I.

    2002-02-01

    Amplitude-phase characteristics (APCs) of surface air temperature (SAT) annual cycle (SAT) are analyzed. From meteorological observations from the XX century and meteorological reanalyses for its second half it is found that alongside with the well-known negative correlation of SAT AC amplitude Ts,1 with annual mean SAT Ts,m a peculiarity in the North Pacific exists where Ts,1 and Ts,m are positively intercorrelated. In contrast, SAT AC phase characteristics show more regional behavior. In particular southward of the characteristic annual mean position of the snow-ice boundary (SIB) SAT AC is harmonized under climate warming while northward it is deharmonized. In the Far East (southward about 50 degree(s)N) SAT AC shifts as a whole with its extrema occurring earlier with increasing annual mean SAT. From the energy-balance climate considerations these tendencies of change of the SAT AC APCs in the middle and high latitudes are associated to the influence of the albedo-SAT feedback due to the SIB movement and in the Far East - to the interannual cloudiness variability. Tendencies of change for SAT AC related to the SIB movement are simulated reasonably well by the climate model of intermediate complexity in the experiments with greenhouse gases atmospheric loading. In contrast, the tendencies resulting from the cloudiness variability are not reproduced by this model.

  14. TacSat-2: Path finder for a Close Space Support Asset

    NASA Astrophysics Data System (ADS)

    Bhopale, A.; Finley, C.

    2008-08-01

    With th e launch of TacSat-2, the Oper ationally Responsive Sp ace (O RS) commun ity had its f irst on- orbit asset and opportunity to prove or disprove the premise that small, in expensiv e, and quickly constructed spacecraf t could perform useful operation al missions when needed and for as long as need ed. All of the components of the comp lex TacSat-2 system had to work together to answer the basic questions, "In a crisis, can a lab-developed spacecraf t and ground architecture competen tly p erform th e mission of systems that cost twen ty times the price and tak e four times as long to develop? Mor eover, can th is system actu ally improve on the responsiveness of Nation al Systems to a certain set of underserv ed Oper ational customers?" When all w as said and done, TacSat-2 was a sp acecraf t that h ad to: 1) Carry th irteen tactical and scientific payloads to orbit, many of which doubled as essen tial, non-redundant subsystems; 2) Launch from an unproven launch base on a last minute "rep lacement" launch vehicle; and 3) Fulfill about 140 on-orbit mission requirements. It had tactical sensors, two unproven communication links, numerous next-gen eration single- string componen ts (e.g., h igh-efficiency propulsion system, thin-film so lar arrays, low-power versatile star camera) , and autonomous softw are to mak e the system more friendly and familiar to Tactical, rather than Spacecraf t Op erators. However, the mission was as mu ch about the implementation as it w as about the components. TacSat-2 was designed for and emp loyed with a different concept of operations ( CONOPS) than tradition al N ational Operational Assets. It w as designed to be th e fir st-ev er Clo se Space Support platform and operated in a manner more analogous to Close Air Support aircraf t than to tr aditional spacecraft. Therefore, th e primary objective of the TacSat-2 mission was to use th e TacSat-2 system to id entify those parts of the spacecr aft, ground system, and CON OPS

  15. A dominant negative mutation in the conserved RNA helicase motif 'SAT' causes splicing factor PRP2 to stall in spliceosomes.

    PubMed Central

    Plumpton, M; McGarvey, M; Beggs, J D

    1994-01-01

    To characterize sequences in the RNA helicase-like PRP2 protein of Saccharomyces cerevisiae that are essential for its function in pre-mRNA splicing, a pool of random PRP2 mutants was generated. A dominant negative allele was isolated which, when overexpressed in a wild-type yeast strain, inhibited cell growth by causing a defect in pre-mRNA splicing. This defect was partially alleviated by simultaneous co-overexpression of wild-type PRP2. The dominant negative PRP2 protein inhibited splicing in vitro and caused the accumulation of stalled splicing complexes. Immunoprecipitation with anti-PRP2 antibodies confirmed that dominant negative PRP2 protein competed with its wild-type counterpart for interaction with spliceosomes, with which the mutant protein remained associated. The PRP2-dn1 mutation led to a single amino acid change within the conserved SAT motif that in the prototype helicase eIF-4A is required for RNA unwinding. Purified dominant negative PRP2 protein had approximately 40% of the wild-type level of RNA-stimulated ATPase activity. As ATPase activity was reduced only slightly, but splicing activity was abolished, we propose that the dominant negative phenotype is due primarily to a defect in the putative RNA helicase activity of PRP2 protein. Images PMID:8112301

  16. The Crystal Structure of Triuranyl Diphosphate Tetrahydrate

    NASA Astrophysics Data System (ADS)

    Locock, Andrew J.; Burns, Peter C.

    2002-01-01

    The hydrated neutral uranyl phosphate, (UO2)3(PO4)2(H2O)4, was synthesized by hydrothermal methods. Intensity data were collected using MoKα radiation and a CCD-based area detector. The crystal structure was solved by direct methods and refined by full-matrix least-squares techniques to agreement indices wR2=0.116 for all data, and R1=0.040, calculated for the 2764 unique observed reflections (∣Fo∣≥4σF). The compound is orthorhombic, space group Pnma, Z=4, a=7.063(1) Å, b=17.022(3) Å, c=13.172(3) Å, V=1583.5(5) Å3. The structure consists of sheets of phosphate tetrahedra and uranyl pentagonal bipyramids, with composition [(UO2)(PO4)]- and the uranophane sheet anion topology. The sheets are connected by a uranyl pentagonal bipyramid in the interlayer that shares corners with a phosphate tetrahedron on each of two adjacent sheets, resulting in an open framework with isolated H2O groups in the larger cavities of the structure.

  17. An investigation into using differential drag for controlling a formation of CubeSats

    NASA Astrophysics Data System (ADS)

    Horsley, M.

    2011-09-01

    As the SSA system upgrades its existing capabilities and adds new ones, the potential offered by inexpensive CubeSat-based systems is growing more attractive. The potential benefits of using CubeSats increase if they are operated in groups to form ‘virtual’ satellites, which have the same functionality of a much larger satellite, but at a fraction of the cost. This paper will investigate the feasibility of using differential aerodynamic forces to control a formation of CubeSats in order to form a virtual satellite. Unfortunately, due to third body gravitational forces, solar radiation pressure, and other perturbing forces, the satellites will drift apart if no control mechanism is employed to maintain the formation. However, providing for a control mechanism is difficult. Using a rocket engine is expensive, increases mission risk, and requires fuel to be carried in the rather limited volume available in a typical CubeSat. However, passive techniques that take advantage of the differential aerodynamic forces experienced by two spacecraft can be used to exert a modest amount of control over the formation. Techniques for doing this have been discussed in the literature. These techniques rely on a simple drag plate, and only allow modest control of the formation in the plane defined by the spacecrafts orbit. An alternative is to treat the drag plate as an aerodynamic control surface, much as is done with an aircraft. This technique allows the control surface to be oriented in a fully 3 dimensional fashion, allowing a greater range of control of the satellite formation. A challenge in treating the drag plate as a 3 dimensional control surface is that the equations of motion describing the relative motions of the satellites become fully coupled with their relative orientations. Thus, controlling the satellite formation by adjusting the relative orientations of the different satellites will require solving a fully coupled set of differential equations and devising a

  18. NASA's Space Launch System: A New Opportunity for CubeSats

    NASA Technical Reports Server (NTRS)

    Robinson, Kimberly F.; Hitt, David; Creech, Stephen D.

    2016-01-01

    Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. Together with the Orion crew vehicle and ground operations at NASA's Kennedy Space Center in Florida, SLS is a foundational capability for NASA's Journey to Mars. From the beginning of the SLS flight program, utilization of the vehicle will also include launching secondary payloads, including CubeSats, to deep-space destinations. Currently, SLS is making rapid progress toward readiness for its first launch in 2018, using the initial configuration of the vehicle, which is capable of delivering 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, Exploration Mission-1, SLS will launch an uncrewed test flight of the Orion spacecraft into distant retrograde orbit around the moon. Accompanying Orion on SLS will be 13 CubeSats, which will deploy in cislunar space. These CubeSats will include not only NASA research, but also spacecraft from industry and international partners and potentially academia. Following its first flight and potentially as early as its second, which will launch a crewed Orion spacecraft into cislunar space, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from Block 1, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for CubeSats. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward

  19. Temporal Experiment for Storms and Tropical Systems (TEMPEST) CubeSat Constellation

    NASA Astrophysics Data System (ADS)

    Reising, S. C.; Todd, G.; Padmanabhan, S.; Brown, S. T.; Lim, B.; Kummerow, C. D.; Chandra, C. V.; van den Heever, S. C.; L'Ecuyer, T. S.; Luo, Z. J.; Haddad, Z. S.; Munchak, S. J.; Ruf, C. S.; Berg, G.; Koch, T.; Boukabara, S. A.

    2014-12-01

    TEMPEST addresses key science needs related to cloud and precipitation processes using a constellation of five CubeSats with identical five-frequency millimeter-wave radiometers spaced 5-10 minutes apart in orbit. The deployment of CubeSat constellations on satellite launches of opportunity allows Earth system observations to be accomplished with greater robustness, shorter repeat times and at a small fraction of the cost of typical Earth Science missions. The current suite of Earth-observing satellites is capable of measuring precipitation parameters using radar or radiometric observations. However, these low Earth-orbiting satellites provide only a snapshot of each storm, due to their repeat-pass times of many hours to days. With typical convective events lasting 1-2 hours, it is highly unlikely that the time evolution of clouds through the onset of precipitation will be observed with current assets. The TEMPEST CubeSat constellation directly observes the time evolution of clouds and identifies changes in time to detect the moment of the onset of precipitation. The TEMPEST millimeter-wave radiometers penetrate into the cloud to directly observe changes as the cloud begins to precipitate or ice accumulates inside the storm. The evolution of ice formation in clouds is important for climate prediction because it largely drives Earth's radiation budget. TEMPEST improves understanding of cloud processes and helps to constrain one of the largest sources of uncertainty in climate models. TEMPEST provides observations at five millimeter-wave frequencies from 90 to 183 GHz using a single compact instrument that is well suited for a 6U CubeSat architecture and fits well within the NASA CubeSat Launch Initiative (CSLI) capabilities. Five identical CubeSats deployed in the same orbital plane with 5-10 minute spacing at 390-450 km altitude and 50-65 degree inclination capture 3 million observations of precipitation, including 100,000 deep convective events in a one

  20. Small Aircraft Transportation System (SATS): A Collaborative Effort Between Nebraska EPSCoR and NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Implementing SATS in Nebraska will require a number of changes, both technical and administrative. SATS will require major improvements in the infrastructure of Nebraska airports. Improving airport infrastructure so that it can accommodate SATS is first and most obvious goal. A second goal is to make airports financially sustainable over the long term with limited federal assistance. A third goal, closely related to the second, is to link the implementation of SATS with anticipated local economic growth. This can leverage local funds without tax increases, enhance the equity of the finance approach, improve planning of facility size, and reduce long-term per unit cost. Many of these goals are national issues, and presumably federal policy will determine how these goals are addressed. This study examines several financing options and discusses their ease of application to Nebraska's airports.

  1. Scholastic Assessment Test (SAT) Results, 1998-99. Measuring Up. E&R Report No. 00.04.

    ERIC Educational Resources Information Center

    Fejoku, Caroline Gay

    This report presents Scholastic Assessment Test (SAT) results for high school seniors in the Wake County Public School System (WCPSS), North Carolina. In Wake County, the number of seniors taking the test rose to 3,496 in 1998-99, an increase from 3,377 in 1997-98 (3.5%). The average SAT score for WCPSS seniors in 1998-99 (1059) was the third…

  2. Pre-Flight Analysis, Test Evaluation and Flight Verification of the Thermal System of Tohoku University SPRITE-SAT

    NASA Astrophysics Data System (ADS)

    Sakamoto, Yuji; Nakazato, Yasuhiro; Sawakami, Tomoki; Yoshida, Kazuya; Takahashi, Yukihiro

    The microsatellite SPRITE-SAT developed by Tohoku University was launched in January 2009. Regarding the thermal system of SPRITE-SAT, the mathematical model, the parameter determination for the heat transfer coefficients, and the comparison between the estimate and real temperature in flight mode are shown in this paper. The precision of thermal analysis using the simple 7-node model was solved. The estimate error of temperature in orbit is less than 5 degrees Celsius in panels with most of instruments.

  3. Sustained attention in mice: expanding the translational utility of the SAT by incorporating the Michigan Controlled Access Response Port (MICARP)

    PubMed Central

    St. Peters, Megan; Cherian, Ajeesh Koshy; Bradshaw, Marc; Sarter, Martin

    2011-01-01

    Advances in mouse genetic technology have spurred increasing interest in the development of cognitive tasks for mice. Here, we describe and discuss the modifications necessary to adapt a task for the assessment of sustained attention performance for use in mice, including for taxing the top-down control of such performance. The validity of the Sustained Attention Task (SAT), including the distractor version (dSAT), have previously been demonstrated in rats and humans. This task requires moveable or retractable operanda; insertion of operanda into the operant chambers cues animals to respond to a prior signal or non-signal event, reporting either a hit or a miss, or a correct rejection or false alarm, respectively. Retractable levers did not support sufficiently high and stable levels of performance in mice. Given the widespread use of static nose-poke devices for testing operant performance in mice, we therefore designed and fabricated a retractable nose-poke device. As this device extends into chambers, a hole for nose-poking is slowly opened and closed again as the device retracts (termed the “Michigan Controlled Access Response Port”; MICARP). Results describe the effects of variation of signal duration and event rate, trial outcome and trial type probability, effects of mice deprivation levels, and the reliability of SAT and dSAT performance. Mice perform the SAT and dSAT at levels comparable to those observed in rats. This task will be of assistance in expanding the translational usefulness of the SAT and dSAT. PMID:21888929

  4. The liver and kidney expression of sulfate anion transporter sat-1 in rats exhibits male-dominant gender differences.

    PubMed

    Brzica, Hrvoje; Breljak, Davorka; Krick, Wolfgang; Lovrić, Mila; Burckhardt, Gerhard; Burckhardt, Birgitta C; Sabolić, Ivan

    2009-04-01

    The sulfate anion transporter (sat-1, Slc26a1) has been cloned from rat liver, functionally characterized, and localized to the sinusoidal membrane in hepatocytes and basolateral membrane (BLM) in proximal tubules (PT). Here, we confirm previously described localization of sat-1 protein in rat liver and kidneys and report on gender differences (GD) in its expression by immunochemical, transport, and excretion studies in rats. The approximately 85-kDa sat-1 protein was localized to the sinusoidal membrane in hepatocytes and BLM in renal cortical PT, with the male-dominant expression. However, the real-time reverse-transcription polymerase chain reaction data indicated no GD at the level of sat-1 mRNA. In agreement with the protein data, isolated membranes from both organs exhibited the male-dominant exchange of radiolabeled sulfate for oxalate, whereas higher oxalate in plasma and 24-h urine indicated higher oxalate production and excretion in male rats. Furthermore, the expression of liver, but not renal, sat-1 protein was: unaffected by castration, upregulated by ovariectomy, and downregulated by estrogen or progesterone treatment in males. Therefore, GD (males > females) in the expression of sat-1 protein in rat liver (and, possibly, kidneys) are caused by the female sex-hormone-driven inhibition at the posttranscriptional level. The male-dominant abundance of sat-1 protein in liver may conform to elevated uptake of sulfate and extrusion of oxalate, causing higher plasma oxalate in males. Oxalate is then excreted by the kidneys via the basolateral sat-1 (males > females) and the apical CFEX (Slc26a6; GD unknown) in PT and eliminated in the urine (males > females), where it may contribute to the male-prevailing development of oxalate urolithiasis. PMID:19002488

  5. Molecular characterization of SAT-2 foot-and-mouth disease virus isolates obtained from cattle during a four-month period in 2001 in Limpopo Province, South Africa.

    PubMed

    Phologane, B S; Dwarka, R M; Haydon, D T; Gerber, L J; Vosloo, W

    2008-12-01

    Foot-and-mouth disease (FMD) is an acute, highly contagious viral infection of domestic and wild cloven-hoofed animals. The virus is a single-stranded RNA virus that has a high rate of nucleotide mutation and amino acid substitution. In southern Africa the South African Territories (SAT) 1-3 serotypes of FMD virus are maintained by large numbers of African buffaloes (Syncerus caffer), which provide a potential source of infection for domestic livestock and wild animals. During February 2001, an outbreak of SAT-2 was recorded in cattle in the FMD control zone of South Africa, adjacent to the Kruger National Park (KNP). They had not been vaccinated against the disease since they form the buffer between the vaccination and free zones but in the face of the outbreak, they were vaccinated as part of the control measures to contain the disease. The virus was, however, isolated from some of them on several occasions up to May 2001. These isolates were characterized to determine the rate of genetic change in the main antigenic determinant, the 1 D/2A gene. Nucleotide substitutions at 12 different sites were identified of which five led to amino acid changes. Three of these occurred in known antigenic sites, viz. the GH-loop and C-terminal part of the protein, and two of these have previously been shown to be subject to positive selection. Likelihood models indicated that the ratio of non-synonymous to synonymous changes among the outbreak sequences recovered from cattle was four times higher than among comparable sequences isolated from wildlife, suggesting that the virus may be under greater selective pressure during rapid transmission events. PMID:19294983

  6. An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

    NASA Technical Reports Server (NTRS)

    Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel, Chitra

    2016-01-01

    National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA).A Study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper will present details of the simulation and analysis that include CubeSat swarm, daughter shipmother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRS Multiple Access (MA) array vs Single Access mode, notional transceiverantenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter mother CubeSat constellation inter-satellite crosslink. Results of Space Science X-band 10 MHz maximum achievable data rate study will be summarized. Assessment of Technology Readiness Level (TRL) of current CubeSat communication technologies capabilities will be presented. Compatibility test of the CubeSat transceiver through NEN and Space Network (SN) will be discussed. Based on the analyses, signal trade studies and technology assessments, the functional design and performance requirements as well as operation concepts for future CubeSat end-to-end communications will be derived.

  7. Performance evaluation of supervised change detection tool on DubaiSat-2 multispectral and pansharp images

    NASA Astrophysics Data System (ADS)

    Almatroushi, Hessa R.

    2014-10-01

    Supervised Change Detection Tool (SCDT) is an in-house developed tool in Emirates Institution for Advanced Science and Technology (EIAST). The developed tool is based on Algebra Change Detection algorithm and multi-class Support Vector Machine classifier and is capable of highlighting the areas of change, describing them, and discarding any falsedetections that result from shadow. Further, it can collect the analysis results, which include the change of class an area went through and the overall change percentage of each class defined, in a Microsoft Word document automatically. This paper evaluates the performance of the SCDT, which was initially developed for DubaiSat-1 multispectral images, on DubaiSat-2 multispectral and pansharp images. Moreover, it compares its performance opposed to Change Detection Analysis (i.e. Post-Classification) in ENVI.

  8. Deploying quantum light sources on nanosatellites II: lessons and perspectives on CubeSat spacecraft

    NASA Astrophysics Data System (ADS)

    Bedington, R.; Truong-Cao, E.; Tan, Y. C.; Cheng, C.; Durak, K.; Grieve, J.; Larsen, J.; Oi, D.; Ling, A.

    2015-10-01

    To enable space-based quantum key distribution proposals the Centre for Quantum Technologies is developing a source of entangled photons ruggedized to survive deployment in space and greatly miniaturised so that it conforms to the strict form factor and power requirements of a 1U CubeSat. The Small Photon Entangling Quantum System is an integrated instrument where the pump, photon pair source and detectors are combined within a single optical tray and electronics package that is no larger than 10 cm x 10 cm x 3 cm. This footprint enables the instrument to be placed onboard nanosatellites or the CubeLab structure aboard the International Space Station. We will discuss the challenges and future prospects of CubeSat-based missions.

  9. The Small Aircraft Transportation System (SATS): Research Collaborations with the NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Tarry, Scott E.; Bowen, Brent D.; Nickerson, Jocelyn S.

    2002-01-01

    The aviation industry is an integral part of the world s economy. Travelers have consistently chosen aviation as their mode of transportation as it is reliable, time efficient and safe. The out- dated Hub and Spoke system, coupled with high demand, has led to delays, cancellations and gridlock. NASA is developing innovative solutions to these and other air transportation problems. This research is being conducted through partnerships with federal agencies, industry stakeholders, and academia, specifically the University of Nebraska at Omaha. Each collaborator is pursuing the NASA General Aviation Roadmap through their involvement in the expansion of the Small Aircraft Transportation System (SATS). SATS will utilize technologically advanced small aircraft to transport travelers to and from rural and isolated communities. Additionally, this system will provide a safe alternative to the hub and spoke system, giving more time to more people through high-speed mobility and increased accessibility.

  10. Influence of multiple scattering on CloudSat measurements in snow: A model study

    NASA Astrophysics Data System (ADS)

    Matrosov, Sergey Y.; Battaglia, Alessandro

    2009-06-01

    The effects of multiple scattering on larger precipitating hydrometers have an influence on measurements of the spaceborne W-band (94 GHz) CloudSat radar. This study presents initial quantitative estimates of these effects in “dry” snow using radiative transfer calculations for appropriate snowfall models. It is shown that these effects become significant (i.e., greater than approximately 1 dB) when snowfall radar reflectivity factors are greater than about 10-15 dBZ. Reflectivity enhancement due to multiple scattering can reach 4-5 dB in heavier stratiform snowfalls. Multiple scattering effects counteract signal attenuation, so the observed CloudSat reflectivity factors in snowfall could be relatively close to the values that would be observed in the case of single scattering and the absence of attenuation.

  11. Microburst Precipitation Measured with the FIREBIRD-II CubeSats

    NASA Astrophysics Data System (ADS)

    Crew, A. B.; Spence, H. E.; Blake, J. B.; Klumpar, D. M.; Larsen, B.; O'Brien, T. P., III; Driscoll, S.; Handley, M.; Legere, J.; Longworth, S.; Mosleh, E.; Smith, S. S.; Springer, L.; Widholm, M.

    2015-12-01

    Focused Investigations of Relativistic Electron Burst Intensity, Range, and Dynamics II (FIREBIRD-II) is an NSF CubeSat mission specifically designed to address key science questions about microbursts. Launched on January 31, 2015 it consists of a pair of identical 1.5U CubeSats, which measure electron microburst precipitation in low-Earth Orbit. Microbursts, which are short (~100ms) intense bursts of electron precipitation to the Earth's atmosphere, are one particular form of electron loss from the Earth's radiation belts and have often been associated with intense chorus wave activity. Each spacecraft carries a pair of solid state detectors to measure the precipitating electrons in 6 energy channels from 200 keV to 1 MeV in energy at 18.75 ms time resolution. We present observations of both individual microburst events (timing, size scales, spectra) as well as larger trends in microburst precipitation observed over the course of the entire mission to date.

  12. Design and Functional Validation of a Mechanism for Dual-Spinning CubeSats

    NASA Technical Reports Server (NTRS)

    Peters, Eric; Dave, Pratik; Kingsbury, Ryan; Marinan, Anne; Wise, Evan; Pong, Chris; Prinkey, Meghan; Cahoy, Kerri; Miller, David W.; Sklair, Devon

    2014-01-01

    The mission of the Micro-sized Microwave Atmospheric Satellite (MicroMAS) is to collect useful atmospheric images using a miniature passive microwave radiometer payload hosted on a low-cost CubeSat platform. In order to collect this data, the microwave radiometer payload must rotate to scan the ground-track perpendicular to the satellite's direction of travel. A custom motor assembly was developed to facilitate the rotation of the payload while allowing the spacecraft bus to remained fixed in the local-vertical, local-horizontal (LVLH) frame for increased pointing accuracy. This paper describes the mechanism used to enable this dual-spinning operation for CubeSats, and the lessons learned during the design, fabrication, integration, and testing phases of the mechanism's development lifecycle.

  13. The Iodine Satellite (iSAT) Hall Thruster Demonstration Mission Concept and Development

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Polzin, Kurt A.; Calvert, Derek; Kamhawi, Hani

    2014-01-01

    The use of iodine propellant for Hall thrusters has been studied and proposed by multiple organizations due to the potential mission benefits over xenon. In 2013, NASA Marshall Space Flight Center competitively selected a project for the maturation of an iodine flight operational feed system through the Technology Investment Program. Multiple partnerships and collaborations have allowed the team to expand the scope to include additional mission concept development and risk reduction to support a flight system demonstration, the iodine Satellite (iSAT). The iSAT project was initiated and is progressing towards a technology demonstration mission preliminary design review. The current status of the mission concept development and risk reduction efforts in support of this project is presented.

  14. The International Space Station as a Launch Platform for CubeSats to Study Space Weather

    NASA Astrophysics Data System (ADS)

    Fish, C. S.; Swenson, C.; Sojka, J. J.

    2011-12-01

    The Ionosphere-Thermosphere-Mesosphere (ITM) region (80 to 250 km) is the boundary between the sensible atmosphere of the Earth and space. This region receives energy and momentum contributions from the sun in the form of solar ultra-violet light and electromagnetic energy coupled via the earth's magnetosphere. The ITM region also receives energy and momentum from the lower atmosphere via waves that break and terminate turbulently in this beach-like region. The various processes, acting both as system drivers and feedback elements in the ITM region, are still poorly understood and the weather of the ITM region cannot be predicted. It is also the area where satellite drag ensures a quick end to satellite lifetimes and it has thus become known as the "inaccessible region." As the terrestrial populations wrestle with the question of "change" (global, climate, etc), our need to continue making long-term measurements is crucial, but is hampered by cost and launch opportunities for even smaller dedicated satellites. The ITM region itself has been identified as a region where almost un-measurable atmospheric changes have very measurable consequences. The International Space Station (ISS), orbiting just above this "inaccessible region", is an ideal platform from which CubeSats can be launched to study the region below. It could become a permanent launch platform for regular or responsive deployment of the small satellite fleet. For example, a group of satellites could be launched in response to a storm or an important lower atmospheric event that has been identified as occurring. Such satellites would last approximately one year before re-entering the upper atmosphere. It is an ideal location from which to routinely launch probes into the inaccessible region below to maintain a long term climate observational capability. The advantage of the ISS is that deployments of these small satellites is not contingent on finding a suitable ground based launch opportunity, whose

  15. Test and On-Orbit Experiences of FalconSAT-3

    NASA Astrophysics Data System (ADS)

    Saylor, W. W.; France, M. E. B.

    2008-08-01

    The fundamental objectives of the capstone design project in the Department of Astronautics at the United States Air Force Academy (USAFA) are for cadets to learn important engineering lessons by executing a real space mission on a Department of Defense-funded satellite project. FalconSAT-3 is a 50 kg, gravity gradient-stabilized designed and built by cadets and launched March 2007 on the first ESPA (Enhanced extended launch vehicle Satellite Payload Adapter) mission. FalconSAT-3 was one of six satellites integrated onto the launch vehicle and the nature of the mission made it that the satellite was subject to the full formality of testing requirements. Two successive gravity gradient booms failed either design requirements or environmental testing; design requirements grew dramatically during the design phase; ambiguous thermal vacuum test results led to uncertainty at launch; and after launch it was not possible to contact the satellite for several weeks.

  16. Economic Analysis of a Laser-Powered, Global Small Aerospacecraft Transportation System (G-SATS)

    NASA Astrophysics Data System (ADS)

    Walton, David; List, George; Myrabo, Leik N.

    2005-04-01

    A first-order economic analysis is performed for a revolutionary transport technology intended for hypersonic world travel — powered by laser energy beamed from satellite solar power stations, with relay mirrors in low Earth orbit. A fleet of 1-person to 5-person, `tractor-beam' lightcraft will enable direct port-to-port (no refueling) trips, half-way around the globe in under an hour — riding suborbital boost-glide trajectories through space. Estimates are presented of vehicle size, ridership, revenues, fleet size, capital, operating and maintenance costs, and expected profitability for a lightcraft-based global transportation system called G-SATS. On a net present value basis, over a 20-year time span, G-SATS should have a profit margin of over 20% — implying not only the ability to be profitable, but also a potential market penetrability that goes well beyond the conservative assumptions made in this analysis.

  17. The NUTS CubeSat Project: Spin-Offs and Technology Development

    NASA Astrophysics Data System (ADS)

    Birkeland, R.; Stein, T. A.; Tommer, M.; Beermann, B.; Petrasch, J.; Gjersvik, A.

    2015-09-01

    The development of CubeSats allows for the conception and implementation of new approaches and technologies. In this paper we present a spin-off and technology innovation resulting from the NTNU Test Satellite (NUTS). NUTS is a 2U CubeSat under development by students of the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway. The satellite is due to launch in 2017 and is based upon in-house developments. We will describe the innovative carbon-fibre frame, radio systems and proposals for an infrared camera for atmospheric gravity waves observations. A NUTS spinoff, the Cosmic Particle Telescope (CPT-SCOPE), will be presented in greater detail since it has been selected for the BEXUS 20 campaign in autumn 2015. CPT-SCOPE is a Norwegian-German compact radiation monitor prototype developed by students.

  18. European satellite broadcasting with L-Sat - Technical concept and experimental program

    NASA Astrophysics Data System (ADS)

    Fromm, H.-H.

    1983-09-01

    The L-Sat payload components for two 12-GHz-band TV channels (one covering Italy and one for experimental national or European experimental broadcasts) are briefly characterized, and preliminary plans for their use after the launch of L-Sat in 1986 are reviewed. A single antenna and receiver are used for the 18-GHz uplink, with a 3.7 x 2.4-deg 3-dB-illuminated zone; channel amplifiers with AGC, 230-W TWTA transmitters, and pointable antennas provide 62-dBW EIRP in channel 24 for Italy and either channel 20 or channel 28 for the experimental program, which is to last 3 years and include both production experiments (such as simultaneous translations and use of multiple subtitles via videotext) and technical trials (such as power control and forward adaptive cross-polar cancellation on the uplink). Maps of the coverage areas, block diagrams, tables, and drawings are provided.

  19. The spiral aftereffect technique (SAT) can differentiate between depressive and somatoform disorder patients.

    PubMed

    Olsson, Lars

    2014-04-01

    This study examined how differences in visuo-perceptual patterns are related to psychopathology. Fifty-six patients (37 women, 19 men; M age = 43.8 yr., SD = 13.4) with a main diagnosis of unipolar depression and 42 patients (22 women, 20 men; M age = 42.0 yr., SD = 11.1) with a main diagnosis of somatoform disorder were compared. The duration and trend of a visual motion aftereffect were measured with the Spiral Aftereffect Technique (SAT). The results indicated that successively increasing aftereffect durations characterized the depressive patients, whereas patterns of very short or short final aftereffect preceded by successively decreasing aftereffect durations characterized the patients with a somatoform disorder. The SAT is thus a valuable tool for linking objectively measured perceptual-personality characteristics with some mental disorders. PMID:24897884

  20. Sistema Planeta-Satélite. Simulación orbital y potenciales gravitatorios

    NASA Astrophysics Data System (ADS)

    Medina, C.; Carrillo, M.

    Se presenta un programa (desarrollado en Quick Basic 4.5) que simula, en tres dimensiones, el movimiento orbital de un satélite (o luna) alrededor de un planeta, al tiempo que calcula y grafica, en un plano, el potencial gravitatorio del sistema en función de la distancia al planeta. Para la simulación orbital, se emplea la matriz de transformación entre el sistema del planeta y el plano orbital. Para el cálculo y graficación del potencial se aplica un desarrollo en serie hasta el segundo orden, que da cuenta del efecto de achatamiento de los polos, en caso de que éste exista. Las longitudes de los ejes del planeta, la masa de éste y del satélite, sus tamaños aparentes, y los parámetros orbitales son introducidos por el usuario.