Artificial gravity as a multi-system countermeasure: effects on cognitive function.

PubMed

Seaton, Kimberly A; Slack, Kelley J; Sipes, Walter; Bowie, Kendra

2007-07-01

The Space Flight Cognitive Assessment Tool for Windows (WinSCAT) is used on the International Space Station to evaluate cognitive functioning after physical insult or trauma. The current study uses WinSCAT to assess cognitive functioning in a space flight analog (bed rest) environment where intermittent artificial gravity (AG) is being tested as a countermeasure. Fifteen male subjects (8 treatment, 7 control), who participated in 21 days of 6 degree head-down tilt bed rest, were assessed during the acclimatization phase, bed rest phase, and recovery phase. Individual differences were found within both the treatment and control groups. The treatment group accounted for more off-nominal WinSCAT scores than the control group. The length of time spent in bed rest was not associated with a change in cognitive function. Individual differences in underlying cognitive ability and motivation level are other possible explanations for the current findings.

Social and ecological correlates of space use patterns in Bwindi mountain gorillas.

PubMed

Seiler, Nicole; Boesch, Christophe; Stephens, Colleen; Ortmann, Sylvia; Mundry, Roger; Robbins, Martha M

2018-04-01

Space use patterns determine access to resources necessary for survival and reproduction. Although it is recognized that the interplay between social and ecological variables shapes spacing patterns, few studies in group-living animals have simultaneously assessed their importance in a comprehensive approach using different spatiotemporal space use measures. In territorial species, such patterns are strongly determined by between-group competition, but its impact in non-territorial species is poorly understood. To better understand the role of social and ecological variables in non-territorial mountain gorillas (Gorilla beringei beringei), we simultaneously evaluated the impact of between-group competition (local gorilla population density and frequency of intergroup encounters) and within-group competition (group size) on space use patterns in 13 gorilla groups in Bwindi Impenetrable National Park, Uganda, while also examining variation in food availability (herbaceous food availability and level of frugivory). We found evidence of between-group competition, indicated by a decline of both monthly home range size and frequency of revisits to each part of the home range as the local gorilla population density increased and by an increase in daily travel distance on days when intergroup encounters occurred. Within-group feeding competition was inferred by a decrease in the frequency of revisits as group size increased. Lastly, food availability influenced the gorillas' spacing patterns, as indicated by a decline in monthly home range size as herbaceous food availability increased and by an increase in daily travel distance as the degree of frugivory increased. In sum, our results suggest that Bwindi gorillas adapted their space use according to the constraints of intraspecific competition and the availability of food resources. We provide some of the first evidence of between-group competition influencing spacing patterns in a non-territorial species. This study suggests a gradient between territoriality and non-territoriality, along which the level of between-group competition varies. © 2018 Wiley Periodicals, Inc.

Determining Metacarpophalangeal Flexion Angle Tolerance for Reliable Volumetric Joint Space Measurements by High-resolution Peripheral Quantitative Computed Tomography.

PubMed

Tom, Stephanie; Frayne, Mark; Manske, Sarah L; Burghardt, Andrew J; Stok, Kathryn S; Boyd, Steven K; Barnabe, Cheryl

2016-10-01

The position-dependence of a method to measure the joint space of metacarpophalangeal (MCP) joints using high-resolution peripheral quantitative computed tomography (HR-pQCT) was studied. Cadaveric MCP were imaged at 7 flexion angles between 0 and 30 degrees. The variability in reproducibility for mean, minimum, and maximum joint space widths and volume measurements was calculated for increasing degrees of flexion. Root mean square coefficient of variance values were < 5% under 20 degrees of flexion for mean, maximum, and volumetric joint spaces. Values for minimum joint space width were optimized under 10 degrees of flexion. MCP joint space measurements should be acquired at < 10 degrees of flexion in longitudinal studies.

Pathology of ocular lesions associated with gas supersaturation in white seabass.

PubMed

Smiley, Jeffrey E; Okihiro, Mark S; Drawbridge, Mark A; Kaufmann, Ronald S

2012-03-01

Cultured juvenile white seabass Atractoscion nobilis (WSB) can suffer from intraocular emphysemas and exophthalmia in the hatchery environment. To identify the cause, two size-groups of WSB were exposed to five gas saturation levels, ranging from 98% to 122% total gas pressure (TGP), over a 96-h exposure period in 18 degrees C and 23 degrees C seawater. Histological examination revealed that the gross and subgross lesions associated with gas supersaturation included corneal and orbital emphysema, along with subretinal, optic nerve, and iridial hemorrhage. Corneal emphysema was the most prominent gross lesion, with the severity and prevalence increasing between size-groups and water temperatures as TGP increased. Following the same pattern was orbital emphysema, which affected more than 93% of the fish examined and caused hemorrhage in the subretinal space, around the optic nerve, in the iris, or a combination thereof. Iridial hemorrhage occurred in 91% of the fish examined and decreased significantly with fish size. The prevalence and severity of hemorrhage in the subretinal space increased significantly with TGP and fish size but not with temperature. Optic nerve hemorrhage was absent in small fish exposed at 18 degrees C but increased significantly with temperature and fish size. The reverse was true for the large fish.

[Clinical evaluation of the postburn retention and the metabolism of Imipenem in the third space].

PubMed

Rong, Xin-Zhou; Bei, Chun-Hua; Huang, Xiao-Hua; Li, Qing-Hui

2003-04-01

To explore the half life and retention of Imipenem in the third space. Eight severely burned patients and eight healthy volunteers were enrolled as the burn group (B) and normal control group (C), respectively. HPLC (high performance liquid chromatography) was employed to determine the contents of Imipenem in the plasma, subeschar tissue fluid (STF) and the changes in its pharmacokinetics. Furthermore, the Imipenem content in the third space was calculated according to the systemic edema degree. The half life of Imipenem in STF (2.53 h) was longer than that in plasma (1.73 h), P < 0.05). The Imipenem content in STF increased gradually along with the lapse of time after repeated intravenous infusion of Imipenem, and at the same the total content of imipenem was increased significantly in the third space. There was antibiotic retention in the third space after severe burn injury, and a prolonged action of the drug could be expected when the drug re-entered the blood stream.

Prospective, randomized and controlled trial on magnesium sulfate administration during laparoscopic gastrectomy: effects on surgical space conditions and recovery profiles.

PubMed

Ryu, J H; Koo, B W; Kim, B G; Oh, A Y; Kim, H H; Park, D J; Lee, C M; Kim, S T; Do, S H

2016-11-01

The degree of neuromuscular blockade is one of the important factors that determine the condition of surgical space during laparoscopic surgery. Magnesium sulfate potentiates the actions of neuromuscular blocking agent, and we hypothesized that intraoperative magnesium sulfate infusion may improve surgical space condition during laparoscopic surgery. Eighty-four patients undergoing elective laparoscopic gastrectomy were randomized to receive isotonic saline (group C) or magnesium sulfate (group M, loading dose with 50 mg/kg over 10 min and then 15 mg/kg/h by continuous infusion) to maintain the moderate neuromuscular blockade using rocuronium. Two experienced surgeons scored the quality of surgical space condition using a 5-point surgical rating scale (SRS). The secondary outcomes included recovery profiles, postoperative pain and adverse events. The SRS in group M was higher than that of group C. The proportion of patients with a SRS of 5 (optimal) was 2.7 % in the group C and 40.5 % in the group M (P < 0.0001) although a lower amount of rocuronium was required in group M than group C [24.2 (6.5) mg/h for group M vs. 27.5 (6) mg/h for group C; P = 0.017]. Pain after operation site was less severe in group M than in group C at postoperative 24 h (P = 0.009). Recovery profiles and adverse events were similar between the two groups. Intraoperative administration of magnesium sulfate improved the quality of surgical space conditions and decreased neuromuscular blocking agent requirement and postoperative pain in patients undergoing laparoscopic gastrectomy.

Impact of low cost refurbishable and standard spacecraft upon future NASA space programs. Payload effects follow-on study

NASA Technical Reports Server (NTRS)

1972-01-01

The study has concluded that there are very large space program cost savings to be obtained by use of low cost, refurbishable, and standard spacecraft in conjunction with the shuttle transportation system. The range of space program cost savings for three different groups of programs are shown in quantitative terms. The total savings for the 91 programs will range from $13.4 billion to $18.0 billion depending on the degree of hardware standardization. These savings, principally resulting from payload cost reductions, tangibly support the development costs of the shuttle system.

Natural environment design criteria for the Space Station definition and preliminary design

NASA Astrophysics Data System (ADS)

Vaughan, W. W.; Green, C. E.

1985-03-01

The natural environment design criteria for the Space Station Program (SSP) definition and preliminary design are presented. Information on the atmospheric, dynamic and thermodynamic environments, meteoroids, radiation, magnetic fields, physical constants, etc. is provided with the intension of enabling all groups involved in the definition and preliminary design studies to proceed with a common and consistent set of natural environment criteria requirements. The space station program elements (SSPE) shall be designed with no operational sensitivity to natural environment conditions during assembly, checkout, stowage, launch, and orbital operations to the maximum degree practical.

Natural environment design criteria for the Space Station definition and preliminary design

NASA Technical Reports Server (NTRS)

Vaughan, W. W.; Green, C. E.

1985-01-01

The natural environment design criteria for the Space Station Program (SSP) definition and preliminary design are presented. Information on the atmospheric, dynamic and thermodynamic environments, meteoroids, radiation, magnetic fields, physical constants, etc. is provided with the intension of enabling all groups involved in the definition and preliminary design studies to proceed with a common and consistent set of natural environment criteria requirements. The space station program elements (SSPE) shall be designed with no operational sensitivity to natural environment conditions during assembly, checkout, stowage, launch, and orbital operations to the maximum degree practical.

Mutual information, neural networks and the renormalization group

NASA Astrophysics Data System (ADS)

Koch-Janusz, Maciej; Ringel, Zohar

2018-06-01

Physical systems differing in their microscopic details often display strikingly similar behaviour when probed at macroscopic scales. Those universal properties, largely determining their physical characteristics, are revealed by the powerful renormalization group (RG) procedure, which systematically retains `slow' degrees of freedom and integrates out the rest. However, the important degrees of freedom may be difficult to identify. Here we demonstrate a machine-learning algorithm capable of identifying the relevant degrees of freedom and executing RG steps iteratively without any prior knowledge about the system. We introduce an artificial neural network based on a model-independent, information-theoretic characterization of a real-space RG procedure, which performs this task. We apply the algorithm to classical statistical physics problems in one and two dimensions. We demonstrate RG flow and extract the Ising critical exponent. Our results demonstrate that machine-learning techniques can extract abstract physical concepts and consequently become an integral part of theory- and model-building.

The Aula EspaZio Gela and the Master of Space Science and Technology in the Universidad del País Vasco (University of the Basque Country)

NASA Astrophysics Data System (ADS)

Sánchez-Lavega, Agustín; Pérez-Hoyos, Santiago; Hueso, Ricardo; del Río-Gaztelurrutia, Teresa; Oleaga, Alberto

2014-09-01

We present the Aula EspaZio Gela, a facility dedicated to teaching Space Science and Technology at the master and doctorate level at the University of the Basque Country (Spain), and to promoting the development of this field in both public and private sectors. The one-year master's degree in Space Science and Technology (60 ECTS (European Credit Transfer and Accumulation System)) offers a group of compulsory courses which give way afterwards to a set of elective matters in which students choose one of two tracks: the scientific, primarily oriented to basic research at the University, or the technological, leading to the space industry and space agencies. After completion of the master thesis, our students have direct access to a PhD in both curricular lines. Here we detail the main features of the master's degree and the experience acquired in three years, including a comparative opinion survey to the students. We also describe the facilities at the Faculty of Engineering consisting of a specific classroom (Aula EspaZio Gela), an Astronomical Observatory, and different laboratories.

Antiradiation vaccine: Technology and development of prophylaxis, prevention and treatment of biological consequences from Heavy Ion irradiation.

NASA Astrophysics Data System (ADS)

Popov, Dmitri; Maliev, Vecheslav

Introduction: An anti-radiation vaccine could be an important part of a countermeasures reg-imen for effective radioprotection, immunoprophylaxis and immunotherapy of the acute radi-ation syndromes (ARS) after gamma-irradiation, neutron irradiation or heavy ion irradiation. Reliable protection of non-neoplastic regions of patients with different forms of cancer which undergo to heavy ion therapy ( e.g. Hadron-therapy) can significantly extend the efficiency of the therapeutic course. The protection of cosmonauts astronauts from the heavy ion ra-diation component of space radiation with specific immunoprophylaxis by the anti-radiation vaccine may be an important part of medical management for long term space missions. Meth-ods and experiments: 1. The Antiradiation Vaccine preparation -standard (mixture of toxoid form of Radiation Toxins -SRD-group) which include Cerebrovascular RT Neurotoxin, Car-diovascular RT Neurotoxin, Gastrointestinal RT Neurotoxin, Hematopoietic RT Hematotoxin. Radiation Toxins Specific Radiation Determinant Group were isolated from a central lymph of gamma-irradiated animals with Cerebrovascular, Cardiovascular, Gastrointestiinal, Hematopoi-etic forms of ARS. Devices for γ-radiation are "Panorama", "Puma". 2. Heavy ion exposure was accomplished at Department of Scientific Research Institute of Nuclear Physics, Dubna, Russia. The heavy ions irradiation was generated in heavy ion (Fe56) accelerator -UTI. Heavy Ion linear transfer energy -2000-2600 KeV mkm, 600 MeV U. Absorbed Dose -3820 Rad. 3. Experimental Design: Rabbits from all groups were irradiated by heavy ion accelerator. Group A -control -10 rabbits; Group B -placebo -5 rabbits; Group C -radioprotectant Cystamine (50 mg kg)-5 rabbits, 15 minutes before irradiation -5 rabbits; Group D -radioprotectant Gammafos (Amifostine -400mg kg ), -5 rabbits; Group E -Antiradiation Vaccine: subcuta-neus administration or IM -2 ml of active substance, 14 days before irradiation -5 rabbits. 4. Results: Group A -100% mortality within two hours after heavy ion irradiation with clinical symptoms of the acute cerebrovascular and cardiovascular syndromes. Group B -100% mortal-ity within 15 hours following irradiation. Group C -100% mortality within 14-15 hours after irradiation. Group D -100% mortality within 15-16 hours after irradiation. In groups A-D, development of the acute radiation cerebrovascular and cardiovascular syndromes as well as ex-tensive burns of skin caused rapid death. Group E -100% mortality in 280-290 hours (12 days) following heavy ion irradiation while animals were exhibiting a combination or individual forms of the acute cerebrovascular, cardiovascular, and gastrointestinal forms and focal skin burns. Discussion: The Antiradiation Vaccine (ARV) and specific immune-prophylaxis are an effective method of neutralization of Radiation Toxins. Vaccination with the ARV significantly extended the survival time after irradiation with heavy ions from two hours up to 300 hours. Clinical signs, clinical features, symptoms were somewhat attenuated. Degree of clinical forms of the Acute Radiation Syndromes were diminished in their severity. Groups A-D demonstrated an extremely severe degree (Degree 4) of Cerebrovascular and Cardiovascular forms of the Acute Radiation Syndromes and lethality 100% was registered in a short time after irradiation. Radi-ation induced burns in this groups (with Cutaneous sub-syndrome of ARS -Degree 4) that were deep with extensive and total dysfunction and possible muscle involvement developed. Animals from group E -Radioprotectant -anti-radiation vaccine had demonstrated later development of the severe Degree 3 or even Degree 2-3 forms of Cerebrovascular and Cardiovascular forms of the ARS and a survival time of irradiated animals was significantly prolonged. Cutaneous sub-syndrome developed in Degree 3 or Degree 2-3. Our results have demonstrated the potential radioprotection efficacy of specific immune-prophylaxis with the Antiradiation vaccine against heavy ion irradiation.

Birational geometry of Fano double spaces of index two

NASA Astrophysics Data System (ADS)

Pukhlikov, Aleksandr V.

2010-10-01

We study birational geometry of Fano varieties realized as double covers \\sigma\\colon V\\to{\\ P}^M, M\\ge5, branched over generic smooth hypersurfaces W=W_{2(M-1)} of degree 2(M-1). We prove that the only structures of a rationally connected fibre space on V are pencil-subsystems of the free linear system \\vert{-\\frac12K_V}\\vert. The groups of birational and biregular self-maps of V coincide: \\operatorname{Bir}V=\\operatorname{Aut}V.

Six pole/eight pole single-phase motor

DOEpatents

Kirschbaum, Herbert S.

1984-01-01

A single phase alternating current electric motor is provided with a main stator winding having two coil groups which are connected to form eight poles for eight-pole operation and to form six poles for six-pole operation. Each group contains four series connected coil elements with each element spanning approximately one-seventh of the periphery of the machine. The coil groups are spaced 180 mechanical degrees apart such that each end coil of one group overlaps one of the end coils of the other group. An auxiliary stator winding having two coil groups with the same relative angular displacement as the main stator winding coil groups is included.

Six pole/eight pole single-phase motor

DOEpatents

Kirschbaum, H.S.

1984-07-31

A single phase alternating current electric motor is provided with a main stator winding having two coil groups which are connected to form eight poles for eight-pole operation and to form six poles for six-pole operation. Each group contains four series connected coil elements with each element spanning approximately one-seventh of the periphery of the machine. The coil groups are spaced 180 mechanical degrees apart such that each end coil of one group overlaps one of the end coils of the other group. An auxiliary stator winding having two coil groups with the same relative angular displacement as the main stator winding coil groups is included. 10 figs.

Spinless hourglass nodal-line semimetals

NASA Astrophysics Data System (ADS)

Takahashi, Ryo; Hirayama, Motoaki; Murakami, Shuichi

2017-10-01

Nodal-line semimetals, one of the topological semimetals, have degeneracy along nodal lines where the band gap is closed. In many cases, the nodal lines appear accidentally, and in such cases it is impossible to determine whether the nodal lines appear or not, only from the crystal symmetry and the electron filling. In this paper, for spinless systems, we show that in specific space groups at 4 N +2 fillings (8 N +4 fillings including the spin degree of freedom), presence of the nodal lines is required regardless of the details of the systems. Here, the spinless systems refer to crystals where the spin-orbit coupling is negligible and the spin degree of freedom can be omitted because of the SU(2) spin degeneracy. In this case the shape of the band structure around these nodal lines is like an hourglass, and we call this a spinless hourglass nodal-line semimetal. We construct a model Hamiltonian as an example and we show that it is always in the spinless hourglass nodal-line semimetal phase even when the model parameters are changed without changing the symmetries of the system. We also establish a list of all the centrosymmetric space groups, under which spinless systems always have hourglass nodal lines, and illustrate where the nodal lines are located. We propose that Al3FeSi2 , whose space-group symmetry is Pbcn (No. 60), is one of the nodal-line semimetals arising from this mechanism.

Microscopic Description of Electric and Magnetic Toroidal Multipoles in Hybrid Orbitals

NASA Astrophysics Data System (ADS)

Hayami, Satoru; Kusunose, Hiroaki

2018-03-01

We derive the quantum-mechanical operator expressions of multipoles under the space-time inversion group. We elucidate that electric and magnetic toroidal multipoles, in addition to ordinary non-toroidal ones, are fundamental pieces to express arbitrary electronic degrees of freedom. We show that electric (magnetic) toroidal multipoles higher than the dipole (monopole) can become active in a hybridized-orbital system. We also demonstrate emergent cross-correlated couplings between the electric, magnetic, and elastic degrees of freedom, such as magneto-electric and magneto(electro)-elastic coupling, under toroidal multipole orders.

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

Donnelly, William; Freidel, Laurent

We consider the problem of defining localized subsystems in gauge theory and gravity. Such systems are associated to spacelike hypersurfaces with boundaries and provide the natural setting for studying entanglement entropy of regions of space. We present a general formalism to associate a gauge-invariant classical phase space to a spatial slice with boundary by introducing new degrees of freedom on the boundary. In Yang-Mills theory the new degrees of freedom are a choice of gauge on the boundary, transformations of which are generated by the normal component of the nonabelian electric field. In general relativity the new degrees of freedommore » are the location of a codimension-2 surface and a choice of conformal normal frame. These degrees of freedom transform under a group of surface symmetries, consisting of diffeomorphisms of the codimension-2 boundary, and position-dependent linear deformations of its normal plane. We find the observables which generate these symmetries, consisting of the conformal normal metric and curvature of the normal connection. We discuss the implications for the problem of defining entanglement entropy in quantum gravity. Finally, our work suggests that the Bekenstein-Hawking entropy may arise from the different ways of gluing together two partial Cauchy surfaces at a cross-section of the horizon.« less

Latino Bilingual Teachers: Negotiating the Figured World of Masculinity

ERIC Educational Resources Information Center

Lara, Gilberto P.; Fránquiz, María E.

2015-01-01

This article focuses on a group of male teachers from Proyecto Bilingüe, a professional development master's degree program for bilingual teachers. The study is guided by one broad research question: How do Latino male bilingual teachers negotiate their identities in a gendered profession? Specifically the study addresses: What spaces for…

Optimal space of linear classical observables for Maxwell k-forms via spacelike and timelike compact de Rham cohomologies

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

Benini, Marco, E-mail: mbenini87@gmail.com, E-mail: mbenini@uni-potsdam.de

Being motivated by open questions in gauge field theories, we consider non-standard de Rham cohomology groups for timelike compact and spacelike compact support systems. These cohomology groups are shown to be isomorphic respectively to the usual de Rham cohomology of a spacelike Cauchy surface and its counterpart with compact support. Furthermore, an analog of the usual Poincaré duality for de Rham cohomology is shown to hold for the case with non-standard supports as well. We apply these results to find optimal spaces of linear observables for analogs of arbitrary degree k of both the vector potential and the Faraday tensor.more » The term optimal has to be intended in the following sense: The spaces of linear observables we consider distinguish between different configurations; in addition to that, there are no redundant observables. This last point in particular heavily relies on the analog of Poincaré duality for the new cohomology groups.« less

Apex-4 for SpaceX CRS-10

NASA Image and Video Library

2017-02-16

APEX-04, or Advanced Plant EXperiments-04, is being prepared in a cold room in the Kennedy Space Center Processing Facility for SpaceX-10. Eric Morris from the cold stowage group fits items into the Double Cold Bag (DCB) which is a non-powered container that keeps the APEX petri plates at +4 degrees Celsius during launch and ascent.. Dr. Anna Lisa Paul of the University of Florida is the principal investigator for APEX-04. Apex-04 is an experiment involving Arabidopsis in petri plates inside the Veggie facility aboard the International Space Station. Since Arabidopsis is the genetic model of the plant world, it is a perfect sample organism for performing genetic studies in spaceflight. The experiment is the result of a grant from NASA’s Space Life and Physical Sciences division.

Comparison of ultrasound imaging in transverse median and parasagittal oblique planes for thoracic epidurals: A pilot study.

PubMed

Khemka, Rakhi; Rastogi, Sonal; Desai, Neha; Chakraborty, Arunangshu; Sinha, Subir

2016-06-01

The use of ultrasound (US) scanning to assess the depth of epidural space to prevent neurological complications is established in current practice. In this study, we hypothesised that pre-puncture US scanning for estimating the depth of epidural space for thoracic epidurals is comparable between transverse median (TM) and paramedian sagittal oblique (PSO) planes. We performed pre-puncture US scanning in 32 patients, posted for open abdominal surgeries. The imaging was done to detect the depth of epidural space from skin (ultrasound depth [UD]) and needle insertion point, in parasagittal oblique plane in PSO group and transverse median plane in TM group. Subsequently, epidural space was localised through the predetermined insertion point by 'loss of resistance' technique and needle depth (ND) to the epidural space was marked. Correlation between the UD and actual ND was calculated and concordance correlation coefficient (CCC) was used to determine the degree of agreement between UD and ND in both the planes. The primary outcome, i.e., the comparison between UD and ND, done using Pearson correlation coefficient, was 0.99 in both PSO and TM groups, and the CCC was 0.93 (95% confidence interval [95% CI]: 0.81-0.97) and 0.90 (95% CI: 0.74-0.96) in PSO and TM groups respectively, which shows a strong positive association between UD and ND in both groups. The use of pre-puncture US scanning in both PSO and TM planes for estimating the depth of epidural space at the level of mid- and lower-thoracic spine is comparable.

Definition of a parametric form of nonsingular Mueller matrices.

PubMed

Devlaminck, Vincent; Terrier, Patrick

2008-11-01

The goal of this paper is to propose a mathematical framework to define and analyze a general parametric form of an arbitrary nonsingular Mueller matrix. Starting from previous results about nondepolarizing matrices, we generalize the method to any nonsingular Mueller matrix. We address this problem in a six-dimensional space in order to introduce a transformation group with the same number of degrees of freedom and explain why subsets of O(5,1), the orthogonal group associated with six-dimensional Minkowski space, is a physically admissible solution to this question. Generators of this group are used to define possible expressions of an arbitrary nonsingular Mueller matrix. Ultimately, the problem of decomposition of these matrices is addressed, and we point out that the "reverse" and "forward" decomposition concepts recently introduced may be inferred from the formalism we propose.

Multi-attribute subjective evaluations of manual tracking tasks vs. objective performance of the human operator

NASA Technical Reports Server (NTRS)

Siapkaras, A.

1977-01-01

A computational method to deal with the multidimensional nature of tracking and/or monitoring tasks is developed. Operator centered variables, including the operator's perception of the task, are considered. Matrix ratings are defined based on multidimensional scaling techniques and multivariate analysis. The method consists of two distinct steps: (1) to determine the mathematical space of subjective judgements of a certain individual (or group of evaluators) for a given set of tasks and experimental conditionings; and (2) to relate this space with respect to both the task variables and the objective performance criteria used. Results for a variety of second-order trackings with smoothed noise-driven inputs indicate that: (1) many of the internally perceived task variables form a nonorthogonal set; and (2) the structure of the subjective space varies among groups of individuals according to the degree of familiarity they have with such tasks.

Population equations for degree-heterogenous neural networks

NASA Astrophysics Data System (ADS)

Kähne, M.; Sokolov, I. M.; Rüdiger, S.

2017-11-01

We develop a statistical framework for studying recurrent networks with broad distributions of the number of synaptic links per neuron. We treat each group of neurons with equal input degree as one population and derive a system of equations determining the population-averaged firing rates. The derivation rests on an assumption of a large number of neurons and, additionally, an assumption of a large number of synapses per neuron. For the case of binary neurons, analytical solutions can be constructed, which correspond to steps in the activity versus degree space. We apply this theory to networks with degree-correlated topology and show that complex, multi-stable regimes can result for increasing correlations. Our work is motivated by the recent finding of subnetworks of highly active neurons and the fact that these neurons tend to be connected to each other with higher probability.

Real-space decoupling transformation for quantum many-body systems.

PubMed

Evenbly, G; Vidal, G

2014-06-06

We propose a real-space renormalization group method to explicitly decouple into independent components a many-body system that, as in the phenomenon of spin-charge separation, exhibits separation of degrees of freedom at low energies. Our approach produces a branching holographic description of such systems that opens the path to the efficient simulation of the most entangled phases of quantum matter, such as those whose ground state violates a boundary law for entanglement entropy. As in the coarse-graining transformation of Vidal [Phys. Rev. Lett. 99, 220405 (2007).

Reconsidering Regionalisation in Global Higher Education: Student Mobility Spaces of the European Higher Education Area

ERIC Educational Resources Information Center

Shields, Robin

2016-01-01

This paper examines international student mobility between member states of the European Higher Education Area (EHEA), a group of 47 countries that committed to reforming their higher education systems to improve the comparability and compatibility of degrees. While increased student mobility is a key goal in its official documents, little…

[The effect of first premolar extraction on third molar angulation and eruption space].

PubMed

Xie, Jing-zhong

2009-12-01

To study the influence of the first premolar extraction on the angulation and eruption space of third molar. One hundred and twenty patients cases of Class I malocclusions were divided into 2 groups by age, who were treated with extraction and non-extraction respectively. The following values was measured: angle of cusp line between the second and third molar(alpha angle),impact state and depth, distance from Rickett's Xi to distal cusp of third mandibular molar along the occlusal plane(Xi-LTM), anterior border of ramus to the third mandibular molar(R-LTM), distance from projection of distal contact point of maxillary third molar to intersection of pterygoid vertical on occlusal plane (PTV-UTM). The change between pre- and post-treatment was calculated and analyzed with SPSS10.0 software package. alpha angle, Xi-LTM, R-LTM, R-LTM were tested with independent-sample t test, impact state and depth was tested with Chi-square test. Influence of age on the values was also evaluated. In younger group, changes of mandibular alpha angle and Xi-LTM in extraction group was 7.16 degrees and 3.22mm, but in elder group, these changes was 2.42 degrees and 2.10mm, all values were significantly larger than non-extraction group (P<0.05). Impact state and depth of third mandibular molar improved in extraction group, while there was no significant changes in the maxilla. The third mandibular molar becomes upright and distal movement after first premolar extraction. The possibility of the third mandibular molar impaction is decreased, but the effect on the maxilla is not significant.

The NASA Space Communications Data Networking Architecture

NASA Technical Reports Server (NTRS)

Israel, David J.; Hooke, Adrian J.; Freeman, Kenneth; Rush, John J.

2006-01-01

The NASA Space Communications Architecture Working Group (SCAWG) has recently been developing an integrated agency-wide space communications architecture in order to provide the necessary communication and navigation capabilities to support NASA's new Exploration and Science Programs. A critical element of the space communications architecture is the end-to-end Data Networking Architecture, which must provide a wide range of services required for missions ranging from planetary rovers to human spaceflight, and from sub-orbital space to deep space. Requirements for a higher degree of user autonomy and interoperability between a variety of elements must be accommodated within an architecture that necessarily features minimum operational complexity. The architecture must also be scalable and evolvable to meet mission needs for the next 25 years. This paper will describe the recommended NASA Data Networking Architecture, present some of the rationale for the recommendations, and will illustrate an application of the architecture to example NASA missions.

Atypical associations to abstract words in Broca's aphasia.

PubMed

Roll, Mikael; Mårtensson, Frida; Sikström, Sverker; Apt, Pia; Arnling-Bååth, Rasmus; Horne, Merle

2012-09-01

Left frontal brain lesions are known to give rise to aphasia and impaired word associations. These associations have previously been difficult to analyze. We used a semantic space method to investigate associations to cue words. The degree of abstractness of the generated words and semantic similarity to the cue words were measured. Three subjects diagnosed with Broca's aphasia and twelve control subjects associated freely to cue words. Results were evaluated with latent semantic analysis (LSA) applied to the Swedish Parole corpus. The aphasic subjects could be clearly distinguished from controls by a lower degree of abstractness in the words they generated. The aphasic group's associations showed a negative correlation between semantic similarity to cue word and abstractness of cue word. By developing novel semantic measures, we showed that Broca's aphasic subjects' word production was characterized by a low degree of abstractness and low degree of coherence in associations to abstract cue words. The results support models where meanings of concrete words are represented in neural networks involving perceptual and motor areas, whereas the meaning of abstract words is more dependent on connections to other word forms in the left frontal region. Semantic spaces can be used in future developments of evaluative tools for both diagnosis and research purposes. Copyright © 2011 Elsevier Srl. All rights reserved.

Local subsystems in gauge theory and gravity

DOE PAGES

Donnelly, William; Freidel, Laurent

2016-09-16

We consider the problem of defining localized subsystems in gauge theory and gravity. Such systems are associated to spacelike hypersurfaces with boundaries and provide the natural setting for studying entanglement entropy of regions of space. We present a general formalism to associate a gauge-invariant classical phase space to a spatial slice with boundary by introducing new degrees of freedom on the boundary. In Yang-Mills theory the new degrees of freedom are a choice of gauge on the boundary, transformations of which are generated by the normal component of the nonabelian electric field. In general relativity the new degrees of freedommore » are the location of a codimension-2 surface and a choice of conformal normal frame. These degrees of freedom transform under a group of surface symmetries, consisting of diffeomorphisms of the codimension-2 boundary, and position-dependent linear deformations of its normal plane. We find the observables which generate these symmetries, consisting of the conformal normal metric and curvature of the normal connection. We discuss the implications for the problem of defining entanglement entropy in quantum gravity. Finally, our work suggests that the Bekenstein-Hawking entropy may arise from the different ways of gluing together two partial Cauchy surfaces at a cross-section of the horizon.« less

Space-multiplexed optical scanner.

PubMed

Riza, Nabeel A; Yaqoob, Zahid

2004-05-01

A low-loss two-dimensional optical beam scanner that is capable of delivering large (e.g., > 10 degrees) angular scans along the elevation as well as the azimuthal direction is presented. The proposed scanner is based on a space-switched parallel-serial architecture that employs a coarse-scanner module and a fine-scanner module that produce an ultrahigh scan space-fill factor, e.g., 900 x 900 distinguishable beams in a 10 degrees (elevation) x 10 degrees (azimuth) scan space. The experimentally demonstrated one-dimensional version of the proposed scanner has a supercontinuous scan, 100 distinguishable beam spots in a 2.29 degrees total scan range, and 1.5-dB optical insertion loss.

Kent in space: Cosmic dust to space debris

NASA Astrophysics Data System (ADS)

McDonnell, J. A. M.

1994-10-01

The dusty heritage of the University of Kent's Space Group commenced at Jodrell Bank, Cheshire, U.K., the home of the largest steerable radio telescope. While Professor Bernard Lovell's 250 ft. diameter telescope was used to command the U.S. deep space Pioneer spacecraft, Professor Tony McDonnell, as a research student in 1960, was developing a space dust detector for the US-UK Ariel program. It was successful. With a Ph.D. safely under the belt, it seemed an inevitable step to go for the next higher degree, a B.T.A.] Two years with NASA at Goddard Space Flight Center, Greenbelt, provided excellent qualifications for such a graduation ('Been to America'). A spirited return to the University of Kent at Canterbury followed, to one of the green field UK University sites springing from the Robbins Report on Higher Education. Swimming against the current of the brain drain, and taking a very considerable reduction in salary, it was with some disappointment that he found that the UK Premier Harold Wilson's 'white-hot technological revolution' never quite seemed to materialize in terms of research funding] Research expertise, centered initially on cosmic dust, enlarged to encompass planetology during the Apollo program, and rightly acquired international acclaim, notching up a history of space missions over 25 years. The group now comprises 38 people supported by four sources: the government's Research Councils, the University, the Space Agencies and Industry. This paper describes the thrust of the group's Research Plan in Space Science and Planetology; not so much based on existing international space missions, but more helping to shape the direction and selection of space missions ahead.

Student Perceptions of Social Learning Space: Designing and Implementing a Co-Operative Assessment Task in Pharmacology

ERIC Educational Resources Information Center

Moni, Roger W.; Depaz, Iris; Lluka, Lesley J.

2008-01-01

We report findings from a case study of co-operative, group-based assessment in Pharmacology for second-year undergraduates at The University of Queensland, Australia. Students enrolled in the 2005 Bachelor of Science and 2006 Bachelor of Pharmacy degree programs, were early users of the university's new Collaborative Teaching and Learning Centre…

Third Space Strategists: International Students Negotiating the Transition from Pathway Program to Postgraduate Coursework Degree

ERIC Educational Resources Information Center

Benzie, Helen

2015-01-01

Pathway programs exist to prepare students for progression into university degrees but the transition experience for many students may not be as smooth as is suggested by the notion of the pathway. While attending a pathway program and at the beginning of their university degree, students may be in a third space, a liminal space where they engage…

Visuotopic organization of the cebus pulvinar: a double representation the contralateral hemifield.

PubMed

Gattass, R; Oswaldo-Cruz, E; Sousa, A P

1978-08-18

The projection of the visual field in the pulvinar nucleus was studied in 17 Cebus monkeys using electrophysiological techniques. Visual space is represented in two regions of the pulvinar; (1) the ventrolateral group, Pvlg, comprising nuclei P delta, P delta, P gamma, P eta and P mu 1; and (2) P mu. In the first group, which corresponds to the pulvinar inferior and ventral part of the pulvinar lateralis, we observed a greater respresentation of the central part of the visual field. Approximately 58% of the volume of the ventrolateral group is concerned with the visual space within 10 degrees of the fovea. This portion of the visual field is represented at its lateral aspects, mainly close to the level of the caudal pole of the lateral geniculate nucleus (LGN). Projection of the vertical meridian runs along its lateral border while that of the horizontal one is found running from the dorsal third of the LGN's hilus to the medial border of the ventro-lateral group. The lower quadrant is represented at its dorsal portion while the upper quadrant is represented at the ventral one. In Pmu the representation is rotated 90 degrees clockwise around the rostrocaudal axis: the vertical meridian is found at the ventromedial border of this nucleus. Thus, the lower quadrant is represented at the later portion of Pmu and the upper at its medial portion. Both projections are restricted to the contralateral hemifield.

E55_Inflight_Purdue_University_2018_0511_2329_651933

NASA Image and Video Library

2018-05-14

SPACE STATION CREW MEMBER RECEIVES HONORARY DEGREE IN ORBIT----- Aboard the International Space Station, Expedition 55 Flight Engineer Drew Feustel of NASA received an honorary doctorate degree from his alma mater, Purdue University, during a unique ground-to-space ceremony on May 11. Feustel, who previously received a Bachelor of Science degree in Solid Earth Sciences and a Master of Science degree in Geophysics from Purdue, was hooded by his crewmate, Purdue graduate Scott Tingle of NASA, who has a Master of Science degree in Mechanical Engineering from the institution. The ceremony originated at Purdue, whose president, Mitch Daniels, introduced the crew members on orbit.

The multidimensional behavioural hypervolumes of two interacting species predict their space use and survival

PubMed Central

Lichtenstein, James L. L.; Wright, Colin M; McEwen, Brendan; Pinter-Wollman, Noa; Pruitt, Jonathan N.

2018-01-01

Individual animals differ consistently in their behaviour, thus impacting a wide variety of ecological outcomes. Recent advances in animal personality research have established the ecological importance of the multidimensional behavioural volume occupied by individuals and by multispecies communities. Here, we examine the degree to which the multidimensional behavioural volume of a group predicts the outcome of both intra- and interspecific interactions. In particular, we test the hypothesis that a population of conspecifics will experience low intraspecific competition when the population occupies a large volume in behavioural space. We further hypothesize that populations of interacting species will exhibit greater interspecific competition when one or both species occupy large volumes in behavioural space. We evaluate these hypotheses by studying groups of katydids (Scudderia nymphs) and froghoppers (Philaenus spumarius), which compete for food and space on their shared host plant, Solidago canadensis. We found that individuals in single-species groups of katydids positioned themselves closer to one another, suggesting reduced competition, when groups occupied a large behavioural volume. When both species were placed together, we found that the survival of froghoppers was greatest when both froghoppers and katydids occupied a small volume in behavioural space, particularly at high froghopper densities. These results suggest that groups that occupy large behavioural volumes can have low intraspecific competition but high interspecific competition. Thus, behavioural hypervolumes appear to have ecological consequences at both the level of the population and the community and may help to predict the intensity of competition both within and across species. PMID:29681647

An Informal Outreach Model for Fostering Diversity and inclusion in the Sciences

NASA Astrophysics Data System (ADS)

Morris, P. A.; Obot, V.

2006-05-01

In the greater Houston area we have developed an effective informal education model that encourages communication between racial and ethnic groups, increases the base knowledge of space science, and promotes family involvement in science education. Space Science Student Ambassadors (SSSA), part of a NASA funded MUCERPI program, is student led and interacts with the community through interactive demonstrations, mini-classes for schools, museums, youth clubs, neighborhood centers and community family events. The events vary in length from one day to three weeks. The predominantly African American and Hispanic student ambassadors are recruited from inner city high schools and minority serving universities. NASA Johnson Space Center scientists are involved in the science education and training of the students. The students receive training in safety, classroom control, time management and team building skills. The lead SSSA contacts potential venues and establishes the event calendar. The students organize the activities for each venue. The SSSA increase their science knowledge. The diversity of the students and their cordial interactions serve as role models for venue participants. The participants can visually see the lack of ethnic or racial boundaries as the ambassadors interact with each other and the audience. Many of our SSSA have stated in evaluations that they have learned more about space science in our program than in their classes. Some of our SSSA are now pursuing graduate degrees in the geosciences. These students, prior to their involvement in our program, would not have pursued graduate degrees or they may have pursued degrees in other fields.

Synthesis and Structural Characterization of Tris(dimethyldithiocarbamate)Indium(III), In[S2CN(CH3)2]3

NASA Technical Reports Server (NTRS)

Clark, Eric B.; Breen, Marc L.; Fanwick, Phillip E.; Hepp, Aloysius F.; Duraj, Stan A.

1998-01-01

The synthesis and structure of the indium dithiocarbamate, In[SCN(CH3)2]3*1/2 4-mepy (4-mepy = 4-methylpyridine), is described. Indium metal was oxidized by tetramethylthiuramdisulfide in 4-methylpyridine at 25C to form a new, homoleptic indium(HI) dithiocarbamate in yields exceeding 60%. In[S2CN(CH3)213 exists as a discrete molecule with a distorted-octahedral geometry. The compound crystallizes in the P 1-bar (No. 2) space group with a = 9.282(l)A, b = 10.081(1)A, c = 12.502 A, alpha= 73.91 (1) degrees, beta = 70.21(1) degrees, gamma = 85.84(1) degrees, Z = 2,v(A(exp 3)) =1057.3(3), R = 0.046, and R(sub w) = 0.061.

In situ dehydration behavior of zeolite-like pentagonite: A single-crystal X-ray study

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

Danisi, Rosa Micaela, E-mail: rosa.danisi@krist.unibe.ch; Armbruster, Thomas; Lazic, Biljana

2013-01-15

The structural modifications upon heating of pentagonite, Ca(VO)(Si{sub 4}O{sub 10}){center_dot}4H{sub 2}O (space group Ccm2{sub 1}, a=10.3708(2), b=14.0643(2), c=8.97810(10) A, V=1309.53(3) A{sup 3}) were investigated by in situ temperature dependent single-crystal X-ray structure refinements. Diffraction data of a sample from Poona district (India) have been measured in steps of 25 up to 250 Degree-Sign C and in steps of 50 Degree-Sign C between 250 and 400 Degree-Sign C. Pentagonite has a porous framework structure made up by layers of silicate tetrahedra connected by V{sup 4+}O{sub 5} square pyramids. Ca and H{sub 2}O molecules are extraframework occupants. Room temperature diffraction data allowedmore » refinement of H positions. The hydrogen-bond system links the extraframework occupants to the silicate layers and also interconnects the H{sub 2}O molecules located inside the channels. Ca is seven-fold coordinated forming four bonds to O of the tetrahedral framework and three bonds to extraframework H{sub 2}O. The H{sub 2}O molecule at O9 showing a high displacement parameter is not bonded to Ca. The dehydration in pentagonite proceeds in three steps. At 100 Degree-Sign C the H{sub 2}O molecule at O8 was released while O9 moved towards Ca. As a consequence the displacement parameter of H{sub 2}O at O9 halved compared to that at room temperature. The unit-cell volume decreased to 1287.33(3) A{sup 3} leading to a formula with 3H{sub 2}O per formula unit (pfu). Ca remained seven-fold coordinated. At 175 Degree-Sign C Ca(VO)(Si{sub 4}O{sub 10}){center_dot}3H{sub 2}O transformed into a new phase with 1H{sub 2}O molecule pfu characterized by doubling of the c axis and the monoclinic space group Pn. Severe bending of specific T--O--T angles led to contraction of the porous three-dimensional framework. In addition, H{sub 2}O at O9 was expelled while H{sub 2}O at O7 approached a position in the center of the channel. The normalized volume decreased to 1069.44(9) A{sup 3}. The Ca coordination reduced from seven- to six-fold. At 225 Degree-Sign C a new anhydrous phase with space group Pna2{sub 1} but without doubling of c had formed. Release of H{sub 2}O at O7 caused additional contraction of T--O--T angles and volume reduction (V=1036.31(9) A{sup 3}). Ca adopted five-fold coordination. During heating excursion up to 400 Degree-Sign C this anhydrous phase remained preserved. Between room temperature and 225 Degree-Sign C the unit-cell volume decreased by 21% due to dehydration. The dehydration steps compare well with the thermo-gravimetric data reported in the literature. - Graphical abstract: Pentagonite structure at room temperature and at 225 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer We investigate the relationship between the removal of H{sub 2}O molecules and structural modifications of the framework of pentagonite. Black-Right-Pointing-Pointer Pentagonite undergoes phase transitions upon heating. Black-Right-Pointing-Pointer We analyze similarities and differences between pentagonite and related structures.« less

Polarization measurements through space-to-ground atmospheric propagation paths by using a highly polarized laser source in space.

PubMed

Toyoshima, Morio; Takenaka, Hideki; Shoji, Yozo; Takayama, Yoshihisa; Koyama, Yoshisada; Kunimori, Hiroo

2009-12-07

The polarization characteristics of an artificial laser source in space were measured through space-to-ground atmospheric transmission paths. An existing Japanese laser communication satellite and optical ground station were used to measure Stokes parameters and the degree of polarization of the laser beam transmitted from the satellite. As a result, the polarization was preserved within an rms error of 1.6 degrees, and the degree of polarization was 99.4+/-4.4% through the space-to-ground atmosphere. These results contribute to the link estimation for quantum key distribution via space and provide the potential for enhancements in quantum cryptography worldwide in the future.

SpaceTech—Postgraduate space education

NASA Astrophysics Data System (ADS)

de Bruijn, Ferdi J.; Ashford, Edward W.; Larson, Wiley J.

2008-07-01

SpaceTech is a postgraduate program geared primarily for mid-career space professionals seeking to gain or improve their expertise in space systems engineering and in business engineering. SpaceTech provides a lifelong impact on its participants by broadening their capabilities, encouraging systematic "end-to-end" thinking and preparing them for any technical or business-related engineering challenges they may encounter. This flexible 1-year program offers high competency gain and increased business skills. It is held in attractive locations in a flexible, multi-cultural environment. SpaceTech is a highly effective master's program certified by the esteemed Technical University of Delft (TUD), Netherlands. SpaceTech provides expert instructors who place no barriers between themselves and participants. The program combines innovative and flexible new approaches with time-tested methods to give participants the skills required for future missions and new business, while allowing participants to meet their work commitments at the same time as they study for their master's degree. The SpaceTech program is conducted in separate sessions, generally each of 2-week duration, separated by periods of some 6-8 weeks, during which time participants may return to their normal jobs. It also includes introductory online course material that the participants can study at their leisure. The first session is held at the TUD, with subsequent sessions held at strategic space agency locations. By participating at two or more of these sessions, attendees can earn certificates of satisfactory completion from TU Delft. By participating in all of the sessions, as well as taking part in the companion Central Case Project (CCP), participants earn an accredited and highly respected master's degree in Space Systems Engineering from the TUD. Seven distinct SpaceTech modules are provided during these sessions: Space Mission Analysis and Design, Systems Engineering, Business Engineering, Interpersonal Skills, Telecommunications, Earth Observation and Navigation. A group CCP, a major asset of this unique program, is a focused project, aimed at the formation of a credible virtual commercial space-related business. Participants exercise space systems engineering fundamentals as well as marketing and business engineering tools, with the goal of creating a financially viable business opportunity. They then present the result, in the form of an unsolicited proposal to potential investors, as well as a varied group of engineers, managers and executives from the space community. During the CCP, participants learn the ties between mission and system design and the potential return to investors. They develop an instinct for the technical concepts and which of the parameters to adjust to make their newly conceived business more effective and profitable.

Active learning in the space engineering education at Technical University of Madrid

NASA Astrophysics Data System (ADS)

Rodríguez, Jacobo; Laverón-Simavilla, Ana; Lapuerta, Victoria; Ezquerro Navarro, Jose Miguel; Cordero-Gracia, Marta

This work describes the innovative activities performed in the field of space education at the Technical University of Madrid (UPM), in collaboration with the center engaged by the European Space Agency (ESA) in Spain to support the operations for scientific experiments on board the International Space Station (E-USOC). These activities have been integrated along the last academic year of the Aerospatiale Engineering degree. A laboratory has been created, where the students have to validate and integrate the subsystems of a microsatellite by using demonstrator satellites. With the acquired skills, the students participate in a training process centered on Project Based Learning, where the students work in groups to perform the conceptual design of a space mission, being each student responsible for the design of a subsystem of the satellite and another one responsible of the mission design. In parallel, the students perform a training using a ground station, installed at the E-USOC building, which allow them to learn how to communicate with satellites, how to download telemetry and how to process the data. This also allows students to learn how the E-USOC works. Two surveys have been conducted to evaluate the impact of these techniques in the student engineering skills and to know the degree of satisfaction of students with respect to the use of these learning methodologies.

Method of orbit sums in the theory of modular vector invariants

NASA Astrophysics Data System (ADS)

Stepanov, S. A.

2006-12-01

Let F be a field, V a finite-dimensional F-vector space, G\\leqslant \\operatorname{GL}_F(V) a finite group, and V^m=V\\oplus\\dots\\oplus V the m-fold direct sum with the diagonal action of G. The group G acts naturally on the symmetric graded algebra A_m=F \\lbrack V^m \\rbrack as a group of non-degenerate linear transformations of the variables. Let A_m^G be the subalgebra of invariants of the polynomial algebra A_m with respect to G. A classical result of Noether [1] says that if \\operatorname{char}F=0, then A_m^G is generated as an F-algebra by homogeneous polynomials of degree at most \\vert G\\vert, no matter how large m can be. On the other hand, it was proved by Richman [2], [3] that this result does not hold when the characteristic of F is positive and divides the order \\vert G\\vert of G. Let p, p>2, be a prime number, F=F_p a finite field of p elements, V a linear F_p-vector space of dimension n, and H\\leqslant \\operatorname{GL}_{F_p}(V) a cyclic group of order p generated by a matrix \\gamma of a certain special form. In this paper we describe explicitly (Theorem 1) one complete set of generators of A_m^H. After that, for an arbitrary complete set of generators of this algebra we find a lower bound for the highest degree of the generating elements of this algebra. This is a significant extension of the corresponding result of Campbell and Hughes [4] for the particular case of n=2. As a consequence we show (Theorem 3) that if m>n and G\\ge H is an arbitrary finite group, then each complete set of generators of A_m^G contains an element of degree at least 2(m-n+2r)(p-1)/r, where r=r(H) is a positive integer dependent on the structure of the generating matrix \\gamma of the group H. This result refines considerably the earlier lower bound obtained by Richman [3].

Apex-4 for SpaceX CRS-10

NASA Image and Video Library

2017-02-16

APEX-04, or Advanced Plant EXperiments-04, is being prepared in a cold room in the Kennedy Space Center Processing Facility for SpaceX-10. Eric Morris from the cold stowage group places the APEX-04 science kits into the Double Cold Bag (DCB), which is a non-powered container that keeps the APEX petri plates at +4 degrees Celsius during launch and ascent. The cold bricks in the lower right of the photo are placed in the DCB prior to closure. Dr. Anna Lisa Paul of the University of Florida is the principal investigator for APEX-04. Apex-04 is an experiment involving Arabidopsis in petri plates inside the Veggie facility aboard the International Space Station. Since Arabidopsis is the genetic model of the plant world, it is a perfect sample organism for performing genetic studies in spaceflight. The experiment is the result of a grant from NASA’s Space Life and Physical Sciences division.

Six degree of freedom manual controls study report

NASA Technical Reports Server (NTRS)

Mckinnon, G. M.; Lippay, A.; King, M. L.

1982-01-01

The feasibility of using degree of freedom manual controls in space in an on orbit environment was determined. Several six degree of freedom controls were tested in a laboratory environment, and replica controls were used to control robot arms. The selection of six degrees of freedom as a design goal was based on the fact that six degrees are sufficient to define the location and orientation of a rigid body in space.

Water Contact Angle Dependence with Hydroxyl Functional Groups on Silica Surfaces under CO2 Sequestration Conditions.

PubMed

Chen, Cong; Zhang, Ning; Li, Weizhong; Song, Yongchen

2015-12-15

Functional groups on silica surfaces under CO2 sequestration conditions are complex due to reactions among supercritical CO2, brine and silica. Molecular dynamics simulations have been performed to investigate the effects of hydroxyl functional groups on wettability. It has been found that wettability shows a strong dependence on functional groups on silica surfaces: silanol number density, space distribution, and deprotonation/protonation degree. For neutral silica surfaces with crystalline structure (Q(3), Q(3)/Q(4), Q(4)), as silanol number density decreases, contact angle increases from 33.5° to 146.7° at 10.5 MPa and 318 K. When Q(3) surface changes to an amorphous structure, water contact angle increases 20°. Water contact angle decreases about 12° when 9% of silanol groups on Q(3) surface are deprotonated. When the deprotonation degree increases to 50%, water contact angle decreases to 0. The dependence of wettability on silica surface functional groups was used to analyze contact angle measurement ambiguity in literature. The composition of silica surfaces is complicated under CO2 sequestration conditions, the results found in this study may help to better understand wettability of CO2/brine/silica system.

Serre duality, Abel's theorem, and Jacobi inversion for supercurves over a thick superpoint

NASA Astrophysics Data System (ADS)

Rothstein, Mitchell J.; Rabin, Jeffrey M.

2015-04-01

The principal aim of this paper is to extend Abel's theorem to the setting of complex supermanifolds of dimension 1 | q over a finite-dimensional local supercommutative C-algebra. The theorem is proved by establishing a compatibility of Serre duality for the supercurve with Poincaré duality on the reduced curve. We include an elementary algebraic proof of the requisite form of Serre duality, closely based on the account of the reduced case given by Serre in Algebraic groups and class fields, combined with an invariance result for the topology on the dual of the space of répartitions. Our Abel map, taking Cartier divisors of degree zero to the dual of the space of sections of the Berezinian sheaf, modulo periods, is defined via Penkov's characterization of the Berezinian sheaf as the cohomology of the de Rham complex of the sheaf D of differential operators. We discuss the Jacobi inversion problem for the Abel map and give an example demonstrating that if n is an integer sufficiently large that the generic divisor of degree n is linearly equivalent to an effective divisor, this need not be the case for all divisors of degree n.

Hydrological Climate Classification: Can We Improve on Köppen-Geiger?

NASA Astrophysics Data System (ADS)

Knoben, W.; Woods, R. A.; Freer, J. E.

2017-12-01

Classification is essential in the study of complex natural systems, yet hydrology so far has no formal way to structure the climate forcing which underlies hydrologic response. Various climate classification systems can be borrowed from other disciplines but these are based on different organizing principles than a hydrological classification might use. From gridded global data we calculate a gridded aridity index, an aridity seasonality index and a rain-vs-snow index, which we use to cluster global locations into climate groups. We then define the membership degree of nearly 1100 catchments to each of our climate groups based on each catchment's climate and investigate the extent to which streamflow responses within each climate group are similar. We compare this climate classification approach with the often-used Köppen-Geiger classification, using statistical tests based on streamflow signature values. We find that three climate indices are sufficient to distinguish 18 different climate types world-wide. Climates tend to change gradually in space and catchments can thus belong to multiple climate groups, albeit with different degrees of membership. Streamflow responses within a climate group tend to be similar, regardless of the catchments' geographical proximity. A Wilcoxon two-sample test based on streamflow signature values for each climate group shows that the new classification can distinguish different flow regimes using this classification scheme. The Köppen-Geiger approach uses 29 climate classes but is less able to differentiate streamflow regimes. Climate forcing exerts a strong control on typical hydrologic response and both change gradually in space. This makes arbitrary hard boundaries in any classification scheme difficult to defend. Any hydrological classification should thus acknowledge these gradual changes in forcing. Catchment characteristics (soil or vegetation type, land use, etc) can vary more quickly in space than climate does, which can explain streamflow differences between geographically close locations. Summarizing, this work shows that hydrology needs its own way to structure climate forcing, acknowledging that climates vary gradually on a global scale and explicitly including those climate aspects that drive seasonal changes in hydrologic regimes.

Continuous passive motion with accelerated flexion after total knee arthroplasty.

PubMed

Yashar, A A; Venn-Watson, E; Welsh, T; Colwell, C W; Lotke, P

1997-12-01

The use of continuous passive motion after total knee arthroplasty remains controversial. A new approach, starting continuous passive motion at 70 degrees to 100 degrees flexion in the recovery room (Group I) was evaluated. A randomized, prospective study of 210 consecutive total knee arthroplasties was performed at two institutions. The control population (Group II) started continuous passive motion at 0 degree to 30 degrees, and progressed toward 100 degrees flexion. Flexion at postoperative Day 3 (Group I = 82.5 degrees, Group II = 72.8 degrees), and at discharge (Group I = 89.1 degrees, Group II = 84.3 degrees) were significantly different. There was no significant difference between the groups at 4 weeks (Group I = 5.0 degrees-104.1 degrees, Group II = 5.6 degrees-102.0 degrees), 6 weeks (Group I = 2.3 degrees-104.8 degrees, Group II = 2.7 degrees-103.6 degrees), 12 weeks (Group I = 1.7 degrees-107.7 degrees, Group II = 4.7 degrees-108.2 degrees), or at 1 year (Group I = 0.5 degree-113.2 degrees, Group II = 1.8 degrees-110.5 degrees). In Group I, wound necrosis developed in one patient that required a gastrocnemius flap. This major complication was caused by a tight dressing, and not necessarily to the accelerated flexion continuous passive motion. This investigation shows that continuous passive motion using accelerated flexion allows increased flexion during the hospital stay without increased risk of complications, pain, or blood loss. This has significant implications for achieving safe, early discharge. However, no difference was found at followup of 4 weeks or greater, and this did not add significantly to the final outcome.

Strategies of Healthy Adults Walking on a Laterally Oscillating Treadmill

NASA Technical Reports Server (NTRS)

Brady, Rachel A.; Peters, Brian T.; Bloomberg, Jacob J.

2008-01-01

We mounted a treadmill on top of a six degree-of-freedom motion base platform to investigate locomotor responses produced by healthy adults introduced to a dynamic walking surface. The experiment examined self-selected strategies employed by participants when exposed to continuous, sinusoidal lateral motion of the support surface while walking. Torso translation and step width were used to classify responses used to stabilize gait in a novel, dynamic environment. Two response categories emerged. Participants tended to either fix themselves in space (FIS), allowing the treadbelt to move laterally beneath them, or they fixed themselves to the base (FTB), moving laterally as the motion base oscillated. The degree of fixation in both extremes varied across participants. This finding suggests that normal adults have innate and varied preferences for reacquiring gait stability, some depending more heavily on vision (FIS group) and others on proprioception (FTB group). Keywords: Human locomotion, Unstable surface, Treadmill, Adaptation, Stability

Crystallization of Ulex europaeus lectin I.

PubMed

Vandonselaar, M; Delbaere, L T

1994-10-21

The lectin I from Ulex europaeus (UEAI) has a strong affinity for the H-type 2 human blood group determinant. Single crystals of UEAI have been grown in the monoclinic crystal system. Initial crystals were obtained after 11 months from a solution of 10 mg/ml protein, 40% 2,4-methylpentanediol and 0.1 N acetate buffer at pH 5.2. The technique of washing and reseeding was used to generate large suitable crystals. The space group is C2 with a = 78.84 A, b = 69.85 A, c = 120.62 A, beta = 108.74 degrees and Z = 4; there is one molecular dimer per asymmetric unit and the solvent content is estimated to be 58%. The crystals diffract to at least 2.8 A d spacings and are stable in the X-ray beam for more than three days.

Application of ultrasound processed images in space: Quanitative assessment of diffuse affectations

NASA Astrophysics Data System (ADS)

Pérez-Poch, A.; Bru, C.; Nicolau, C.

The purpose of this study was to evaluate diffuse affectations in the liver using texture image processing techniques. Ultrasound diagnose equipments are the election of choice to be used in space environments as they are free from hazardous effects on health. However, due to the need for highly trained radiologists to assess the images, this imaging method is mainly applied on focal lesions rather than on non-focal ones. We have conducted a clinical study on 72 patients with different degrees of chronic hepatopaties and a group of control of 18 individuals. All subjects' clinical reports and results of biopsies were compared to the degree of affectation calculated by our computer system , thus validating the method. Full statistical results are given in the present paper showing a good correlation (r=0.61) between pathologist's report and analysis of the heterogenicity of the processed images from the liver. This computer system to analyze diffuse affectations may be used in-situ or via telemedicine to the ground.

Application of ultrasound processed images in space: assessing diffuse affectations

NASA Astrophysics Data System (ADS)

Pérez-Poch, A.; Bru, C.; Nicolau, C.

The purpose of this study was to evaluate diffuse affectations in the liver using texture image processing techniques. Ultrasound diagnose equipments are the election of choice to be used in space environments as they are free from hazardous effects on health. However, due to the need for highly trained radiologists to assess the images, this imaging method is mainly applied on focal lesions rather than on non-focal ones. We have conducted a clinical study on 72 patients with different degrees of chronic hepatopaties and a group of control of 18 individuals. All subjects' clinical reports and results of biopsies were compared to the degree of affectation calculated by our computer system , thus validating the method. Full statistical results are given in the present paper showing a good correlation (r=0.61) between pathologist's report and analysis of the heterogenicity of the processed images from the liver. This computer system to analyze diffuse affectations may be used in-situ or via telemedicine to the ground.

Space shuttle: Static aerodynamic characteristics characteristics and control effectiveness for McDonnell-Douglas orbiter configuration for Mach number range of 0.4 to 5.0

NASA Technical Reports Server (NTRS)

Ellis, R. R.

1971-01-01

An experimental aerodynamic wind tunnel investigation was conducted employing a 0.00325 scale model of the McDonnell-Douglas space shuttle orbiter configuration. This investigation was conducted in the NASA/Marshall Space Flight Center 14- by 14- inch trisonic wind tunnel. The investigation was to determine the aerodynamic characteristics of the orbiter over the Mach number range of 0.4 to 5.0, an angle of attack variation from -4 degrees to 50 degrees, and -6 degrees to 9 degrees angle of sideslip. Control surface effectiveness was investigated for elevator, aileron, and rudder deflections.

(Congressional Interest) Network Information and Space Security Center

DTIC Science & Technology

2011-09-30

Zagreb , Croatia (City of Zagreb funding). Conducted three days of meetings with City/University of Zagreb , Croatia officials to structure terms for a...partnership with UCCS. In the short-term, UCCS will develop and deliver several courses in homeland security and assist the University of Zagreb in... Zagreb in maturing the Center of Excellence and designing, developing and delivering masters and doctoral degrees in homeland security. Hosted a group of

How to classify plantar plate injuries: parameters from history and physical examination.

PubMed

Nery, Caio; Coughlin, Michael; Baumfeld, Daniel; Raduan, Fernando; Mann, Tania Szejnfeld; Catena, Fernanda

2015-01-01

To find the best clinical parameters for defining and classifying the degree of plantar plate injuries. Sixty-eight patients (100 metatarsophalangeal joints) were classified in accordance with the Arthroscopic Anatomical Classification for plantar plate injuries and were divided into five groups (0 to IV). Their medical files were reviewed and the incidence of each parameter for the respective group was correlated. These parameters were: use of high heels, sports, acute pain, local edema, Mulder's sign, widening of the interdigital space, pain in the head of the corresponding metatarsal, touching the ground, "drawer test", toe grip and toe deformities (in the sagittal, coronal and transversal planes). There were no statistically significant associations between the degree of injury and use of high-heel shoes, sports trauma, pain at the head of the metatarsal, Mulder's sign, deformity in pronation or displacement in the transversal and sagittal planes (although their combination, i.e. "cross toe", showed a statistically significant correlation). Positive correlations with the severity of the injuries were found in relation to initial acute pain, progressive widening of the interdigital space, loss of "touching the ground", positive results from the "drawer test" on the metatarsophalangeal joint, diminished grip strength and toe deformity in supination. The "drawer test" was seen to be the more reliable and precise tool for classifying the degree of plantar plate injury, followed by "touching the ground" and rotational deformities. It is possible to improve the precision of the diagnosis and the predictions of the anatomical classification for plantar plate injuries through combining the clinical history and data from the physical examination.

Application of the phase extension method in virus crystallography.

PubMed

Reddy, Vijay S

2016-01-01

The procedure for phase extension (PX) involves gradually extending the initial phases from low resolution (e.g., ~8Å) to the high-resolution limit of a diffraction data set. Structural redundancy present in the viral capsids that display icosahedral symmetry results in a high degree of non-crystallographic symmetry (NCS), which in turn translates into higher phasing power and is critical for improving and extending phases to higher resolution. Greater completeness of the diffraction data and determination of a molecular replacement solution, which entails accurately identifying the virus particle orientation(s) and position(s), are important for the smooth progression of the PX procedure. In addition, proper definition of a molecular mask (envelope) around the NCS-asymmetric unit has been found to be important for the success of density modification procedures, such as density averaging and solvent flattening. Regardless of the degree of NCS, the PX method appears to work well in all space groups, provided an accurate molecular mask is used along with reasonable initial phases. However, in the cases with space group P1, in addition to requiring a molecular mask, starting the phase extension at a higher resolution (e.g., 6Å) overcame the previously reported problems due to Babinet phases and phase flipping errors.

Project Based Learning experiences in the space engineering education at Technical University of Madrid

NASA Astrophysics Data System (ADS)

Rodríguez, Jacobo; Laverón-Simavilla, Ana; del Cura, Juan M.; Ezquerro, José M.; Lapuerta, Victoria; Cordero-Gracia, Marta

2015-10-01

This work describes the innovation activities performed in the field of space education since the academic year 2009/10 at the Technical University of Madrid (UPM), in collaboration with the Spanish User Support and Operations Center (E-USOC), the center assigned by the European Space Agency (ESA) in Spain to support the operations of scientific experiments on board the International Space Station. These activities have been integrated within the last year of the UPM Aerospace Engineering degree. A laboratory has been created, where students have to validate and integrate the subsystems of a microsatellite using demonstrator satellites. In parallel, the students participate in a Project Based Learning (PBL) training process in which they work in groups to develop the conceptual design of a space mission. One student in each group takes the role of project manager, another one is responsible for the mission design and the rest are each responsible for the design of one of the satellite subsystems. A ground station has also been set up with the help of students developing their final thesis, which will allow future students to perform training sessions and learn how to communicate with satellites, how to receive telemetry and how to process the data. Several surveys have been conducted along two academic years to evaluate the impact of these techniques in engineering learning. The surveys evaluate the acquisition of specific and generic competences, as well as the students' degree of satisfaction with respect to the use of these learning methodologies. The results of the surveys and the perception of the lecturers show that PBL encourages students' motivation and improves their results. They not only acquire better technical training, but also improve their transversal skills. It is also pointed out that this methodology requires more dedication from lecturers than traditional methods.

Investigation of the vascular reaction of the nasal mucosa in cosmonauts

NASA Technical Reports Server (NTRS)

Yakovleva, I. Y.; Baranova, V. P.

1982-01-01

Rhinopneumometric examinations in 3 positions of the body were undertaken in 36 cosmonauts aged 25 to 45 years, 14 of whom participated in space flights of various lengths. The nasal vascular response standards were defined in persons of the group examined. A subjective characteristic of the nasal vascular, reactions arising during the flight is provided. Examinations of 14 people were performed before and after the space flight. The rise of intranasal resistance in the horizontal body position permits forecasting different degrees of nasal breathing disturbances during a period of acute adaptation to weightlessness owing to vasomotor alterations of the nasal mucous membrane.

Astronautics degrees for the space industry

NASA Astrophysics Data System (ADS)

Gruntman, M.; Brodsky, R. F.; Erwin, D. A.; Kunc, J. A.

2004-01-01

The Astronautics Program (http://astronautics.usc.edu) of the University of Southern California (USC) offers a full set of undergraduate and graduate degree programs in Aerospace Engineering with emphasis in Astronautics. The Bachelor of Science and Master of Science degree programs in Astronautics combine basic science and engineering classes with specialized classes in space technology. The Certificate in Astronautics targets practicing engineers and scientists who enter space-related fields and/or who want to obtain training in specific space-related areas. Many specialized graduate classes are taught by adjunct faculty working at the leading space companies. The Master of Science degree and Certificate are available entirely through the USC Distance Education Network (DEN). Today, the Internet allows us to reach students anywhere in the world through webcasting. The majority of our graduate students, as well as those pursuing the Certificate, work full time as engineers in the space industry and government research and development centers while earning their degrees. The new world of distance learning presents new challenges and opens new opportunities. Distance learning, and particularly the introduction of webcasting, transform the organization of the graduate program and class delivery. We describe in detail the program's academic focus, student reach, and structure of program components. Program development is illustrated by the student enrollment dynamics and related industrial trends; the lessons learned emphasize the importance of feedback from the students and from the space industry.

Maxillary anterior segmental distraction osteogenesis with 2 different types of distractors.

PubMed

Choi, Hye-Young; Hwang, Chung-Ju; Kim, Hee-Jin; Yu, Hyung-Seog; Cha, Jung-Yul

2012-05-01

Maxillary anterior segmental distraction osteogenesis (DO) has been the alternative treatment option for patients with midfacial retrusion. To investigate a potentially more effective maxillary anterior segmental DO, a newly designed intraoral alveolar distractor was applied. The objectives of this study were to investigate the skeletal and dental effects of maxillary anterior segmental DO and the relapse pattern. The study was carried out for 8 patients with unilateral cleft lip and palate (mean age, 16 years 7 months). Four patients were treated with an intraoral appliance (IA), and the remaining with a rigid external distractor (RED). Dental and skeletal measurements were obtained for both groups. These measurements were compared for different time points including pre-DO (T1), post-DO (T2), postconsolidation (T3), and 1-year follow-up (T4). Horizontal change of A point was significantly larger after distraction period (T2) in the RED group (mean, 11.0 mm; median, 10.1 mm) than in the IA group (mean, 6.6 mm; median, 7.4 mm) (P < 0.05). Relapse of A point was observed in both RED (mean, -2.3 mm; median, -2.3 mm) and IA groups (mean, -2.6 mm; median, -1.5 mm) at T4. The vertical position of the anterior nasal spine was found to have moved downward in the RED group (mean, 5.5 mm; median, 4.9 mm) but upward in the IA group (mean, -2.5 mm; median, -2.7 mm) after distraction, showing a significant difference between groups (P < 0.05). Axis of upper incisor increased at T2 in the IA group (mean, 10.4 degrees; median, 11.3 degrees), but decreased in the RED group (mean, -10.2 degrees; median, -9.0 degrees) (P < 0.05). It recovered in the RED group at T4. Maxillary anterior segmental DO is effective for the treatment of patients with cleft lip and palate. The alveolar space is regained, and the facial profile is improved without velopharyngeal problems. Superior results are obtained using the RED appliance for maxillary anterior segmental DO relative to the use of the intraoral distractor appliance.

Dynamically hot galaxies. I - Structural properties

NASA Technical Reports Server (NTRS)

Bender, Ralf; Burstein, David; Faber, S. M.

1992-01-01

Results are reported from an analysis of the structural properties of dynamically hot galaxies which combines central velocity dispersion, effective surface brightness, and effective radius into a new 3-space (k), in which the axes are parameters that are physically meaningful. Hot galaxies are found to divide into groups in k-space that closely parallel conventional morphological classifications, namely, luminous ellipticals, compacts, bulges, bright dwarfs, and dwarf spheroidals. A major sequence is defined by luminous ellipticals, bulges, and most compacts, which together constitute a smooth continuum in k-space. Several properties vary smoothly with mass along this continuum, including bulge-to-disk ratio, radio properties, rotation, degree of velocity anisotropy, and 'unrelaxed'. A second major sequence is comprised of dwarf ellipticals and dwarf spheroidals. It is suggested that mass loss is a major factor in hot dwarf galaxies, but the dwarf sequence cannot be simply a mass-loss sequence, as it has the wrong direction in k-space.

Packet telemetry and packet telecommand - The new generation of spacecraft data handling techniques

NASA Technical Reports Server (NTRS)

Hooke, A. J.

1983-01-01

Because of rising costs and reduced reliability of spacecraft and ground network hardware and software customization, standardization Packet Telemetry and Packet Telecommand concepts are emerging as viable alternatives. Autonomous packets of data, within each concept, which are created within ground and space application processes through the use of formatting techniques, are switched end-to-end through the space data network to their destination application processes through the use of standard transfer protocols. This process may result in facilitating a high degree of automation and interoperability because of completely mission-independent-designed intermediate data networks. The adoption of an international guideline for future space telemetry formatting of the Packet Telemetry concept, and the advancement of the NASA-ESA Working Group's Packet Telecommand concept to a level of maturity parallel to the of Packet Telemetry are the goals of the Consultative Committee for Space Data Systems. Both the Packet Telemetry and Packet Telecommand concepts are reviewed.

Excision of uranium oxide chains and ribbons in the novel one-dimensional uranyl iodates K(2)[(UO(2))3(IO(3))(4)O(2)] and Ba[(UO(2)2(IO(3))(2)O(2)](H(2)O).

PubMed

Bean, A C; Ruf, M; Albrecht-Schmitt, T E

2001-07-30

The alkali metal and alkaline-earth metal uranyl iodates K(2)[(UO(2))(3)(IO(3))(4)O(2)] and Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) have been prepared from the hydrothermal reactions of KCl or BaCl(2) with UO(3) and I(2)O(5) at 425 and 180 degrees C, respectively. While K(2)[(UO(2))(3)(IO(3))(4)O(2)] can be synthesized under both mild and supercritical conditions, the yield increases from <5% to 73% as the temperature is raised from 180 to 425 degrees C. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), however, has only been isolated from reactions performed in the mild temperature regime. Thermal measurements (DSC) indicate that K(2)[(UO(2))(3)(IO(3))(4)O(2)] is more stable than Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) and that both compounds decompose through thermal disproportionation at 579 and 575 degrees C, respectively. The difference in the thermal behavior of these compounds provides a basis for the divergence of their preparation temperatures. The structure of K(2)[(UO(2))(3)(IO(3))(4)O(2)] is composed of [(UO(2))(3)(IO(3))(4)O(2)](2)(-) chains built from the edge-sharing UO(7) pentagonal bipyramids and UO(6) octahedra. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) consists of one-dimensional [(UO(2))(2)(IO(3))(2)O(2)](2)(-) ribbons formed from the edge sharing of distorted UO(7) pentagonal bipyramids. In both compounds the iodate groups occur in both bridging and monodentate binding modes and further serve to terminate the edges of the uranium oxide chains. The K(+) or Ba(2+) cations separate the chains or ribbons in these compounds forming bonds with terminal oxygen atoms from the iodate ligands. Crystallographic data: K(2)[(UO(2))(3)(IO(3))(4)O(2)], triclinic, space group P_1, a = 7.0372(5) A, b = 7.7727(5) A, c = 8.9851(6) A, alpha = 93.386(1) degrees, beta = 105.668(1) degrees, gamma = 91.339(1) degrees, Z = 1; Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), monoclinic, space group P2(1)/c, a = 8.062(4) A, b = 6.940(3) A, c = 21.67(1), beta= 98.05(1) degrees, Z = 4.

Convex Hemiepiphysiodesis: Posterior/anterior in-situ Versus Posterior-only With Pedicle Screw Instrumentation: An Experimental Simulation in Immature Pigs.

PubMed

Bekmez, Senol; Demirkiran, Halil G; Yilmaz, Guney; Akel, Ibrahim; Atilla, Pergin; Muftuoglu, Sevda Fatma; Yazici, Muharrem; Alanay, Ahmet

2016-12-01

Experimental study. Convex growth arrest (CGA) has been commonly used in the treatment of long-sweeping congenital deformities of the immature spine. As there are major drawbacks about the anterior procedure in the conventional CGA method, a new modification has been documented that using only posterior spinal approach with pedicle screw instrumentation. The aim of the study was to compare posterior-only CGA using pedicle screws with combined anterior/posterior in-situ CGA for the findings in histologic, radiologic, and manual palpation examinations in an immature pig model. Twelve 10-weeks old pigs were grouped into 2. In group 1, posterior-only, pedicle screw instrumented CGA was performed on the left side of L1-L4 vertebrae. In group 2, conventional combined posterior and anterior CGA was performed to the left side of L1-L4 vertebrae without instrumentation. All animals were killed twelve weeks after surgery. T11-L5 segments were en-bloc resected and radiologic, histologic, and manual palpation examinations were done. Marked scoliotic (12.2±2.5 and 9.2±1.3 in group 1 and 2, respectively) and kyphotic (11.2±1.0 degrees for the group 1 and 12±5.2 degrees for the group 2, respectively) deformities were noted in both groups, which were caused by hemiepiphysiodesis effect. Anterior and posterior parts of group 2 and posterior part of group 1 demonstrated fusion in histologic and radiologic analyzes. In anterior part of the group 1, marked narrowing on the disk spaces and thinning of growth plates were noted in radiologicg examination, chondrocyte degeneration, and newly-formed bone trabeculae in disk-space were noted in histological examination. In manual palpation, no motion was detected in group 1 and motion was detected in only one segment of one animal in group 2. Anterior growth of the vertebrae can be controlled by application of posterior transpedicular screws and rod. Such an effect can eliminate the need for anterior surgical intervention in convex hemiepiphysiodesis procedures. The instrumented CGA technique provides a satisfactory epiphysiodesis effect both anteriorly and posteriorly, as previously demonstrated by clinical studies.

Space shuttle: Determination of the aerodynamic interference between the space shuttle orbiter, external tank, and solid rocket booster on a 0.004 scale ascent configuration

NASA Technical Reports Server (NTRS)

Ramsey, P. E.; Buchholz, R.; Allen, E. C. JR.; Dehart, J.

1973-01-01

Wind tunnel tests were conducted to determine the aerodynamic interference between the space shuttle orbiter, external tank, and solid rocket booster on a 0.004 scale ascent configuration. Six component aerodynamic force and moment data were recorded over an angle of attack range from minus 10 to plus 10 degrees at zero degree sideslip. A sideslip range of minus 10 to plus 10 degrees at zero degree angle of attack was also tested. The Mach number range was varied from 0.6 to 4.96 with Reynolds number varying between 4.9 and 6.8 times one million per foot.

Water Mass Map from Neutron Spectrometer

NASA Technical Reports Server (NTRS)

2003-01-01

December 8, 2003

This map shows the estimated lower limit of the water content of the upper meter of Martian soil. The estimates are derived from the hydrogen abundance measured by the neutron spectrometer component of the gamma ray spectrometer suite on NASA's Mars Odyssey spacecraft.

The highest water-mass fractions, exceeding 30 percent to well over 60 percent, are in the polar regions, beyond about 60 degrees latitude north or south. Farther from the poles, significant concentrations are in the area bound in longitude by minus 10 degrees to 50 degrees and in latitude by 30 degrees south to 40 degrees north, and in an area to the south and west of Olympus Mons (30 degrees to 0 degrees south latitude and minus 135 degrees to 110 degrees longitude).

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for the NASA Office of Space Science in Washington. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Space Systems, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL.

Ultrasound-guided evaluation of the lumbar subarachnoid space in lateral and sitting positions in pregnant patients to receive elective cesarean operation.

PubMed

Gulay, Ucarli; Meltem, Turkay; Nadir, Sinikoglu Sitki; Aysin, Alagol

2015-01-01

The aim was to compare visibility of the spinal space in sitting and lateral positions, number of attempts, spinal needle depth, skin-dura mater distance and the possible complications; in application of spinal anesthesia, using ultrasound in pregnant patients scheduled to receive elective cesarean operations. The study was conducted prospective-randomly after receiving approval from the ethics committee and the patients' permission. ASA I-II 50 pregnant patients were divided into two groups. The patients in Group SP were those placed in a sitting position and the patients in Group LP were those placed in a lateral position. In both groups, the skin-dura mater distance was recorded through an out-of plane technique accompanied by ultrasound. The depth of the spinal needle was measured. The number of attempts, the level of attempts recorded. The degree of visibility of the vertebral space was observed through ultrasound and was numerically scored. Intraoperative and postoperative complications were recorded. There was no difference between the number of attempts, Modified Bromage Scale and mean measurements of skin-dura mater distance observed through ultrasound. The mean needle depths of Group LP were statistically found significantly higher than Group SP (p=0.002). Our study supports the notion that access to the skin-dura mater distance is longer in the lateral decubitus position when skin-dura mater distance is evaluated by measuring needle depth.

Association between deep neck space abscesses and internal carotid artery narrowing in pediatric patients

PubMed

Derinkuyu, Betül Emine; Boyunağa, Öznur; Polat, Meltem; Damar, Çağrı; Tapısız Aktaş, Anıl; Alımlı, Ayşe Gül; Öztunalı, Çiğdem; Kara, Soner Sertan; Uçar, Murat; Tezer, Hasan

2017-12-19

Background/aim: Our aim was to interpret the effects of deep neck space abscesses on the adjacent carotid artery according to abscess location, as well as to determine narrowing by calculating the mean stenosis ratios.Materials and methods: Neck computed tomography scans and clinical data of 45 children with neck abscesses were evaluated retrospectively for abscess location and internal carotid artery narrowing. The lumen areas of the carotid arteries were measured from standard levels, and stenosis ratios were calculated with two different techniques. The mean stenosis ratios of each group according to abscess location were then compared with the control group.Results: Among the 45 abscesses included in the study, 51.1% (n = 23/45) were located in the peritonsillar region, 37.8% (n = 17/45) were located in the parapharyngeal-lateral retropharyngeal space, and 11.1% (n = 5/45) were in the midline retropharyngeal space. We found a statistically significant difference between the mean stenosis ratios of the ipsilateral side of the parapharyngeal-lateral retropharyngeal abscesses and the control group (P < 0.01).Conclusion: The children with parapharyngeal-lateral retropharyngeal abscesses all had narrowing in the adjacent carotid lumen to some degree. Although most of the patients had no clinical symptoms, radiologists have to be aware of this arterial complication to prevent further progress and fatal complications.

A key heterogeneous structure of fractal networks based on inverse renormalization scheme

NASA Astrophysics Data System (ADS)

Bai, Yanan; Huang, Ning; Sun, Lina

2018-06-01

Self-similarity property of complex networks was found by the application of renormalization group theory. Based on this theory, network topologies can be classified into universality classes in the space of configurations. In return, through inverse renormalization scheme, a given primitive structure can grow into a pure fractal network, then adding different types of shortcuts, it exhibits different characteristics of complex networks. However, the effect of primitive structure on networks structural property has received less attention. In this paper, we introduce a degree variance index to measure the dispersion of nodes degree in the primitive structure, and investigate the effect of the primitive structure on network structural property quantified by network efficiency. Numerical simulations and theoretical analysis show a primitive structure is a key heterogeneous structure of generated networks based on inverse renormalization scheme, whether or not adding shortcuts, and the network efficiency is positively correlated with degree variance of the primitive structure.

Synthesis and Structural Characterization of a Novel Indium Mercapto Derivative [clln(sch2(co)o)2]2-[(4-mepyh)2]2+

NASA Technical Reports Server (NTRS)

Banger, Kulbinder K.; Duraj, Stan A.; Fanwick, Philip E.; Hepp, Aloysius F.; Martock, Robert A.

2004-01-01

The synthesis and structural characterization of a novel In(III) complex is described. The reaction between InCl3 with sodium mercapto-acetic acid, (NaSCH2(CO)OH) in 4-methylpyridine, (CH3(C5H5N), (4-Mepy)) at 25 C affords [ClIn(SCH2(CO)O)2]2- [(4-MepyH)2]2+. X-ray diffraction studies show it to have a distorted square pyramidal geometry, with the [(-SCH2(CO)CO-)] ligands in a trans conformation. The compound crystallizes in the P(raised dash) 1 (No. 2) space group with a = 7.8624 Angstrom, b = 9.950 Angstrom, c = 13.793 Angstrom, alpha = 107.60 degrees, beta= 90.336 degrees, gamma = 98.983 degrees, V = 1014.3 Angstroms (sup 3), R(F(raised circle)) = 0.037, and R(sub w) = 0.048.

Using algebra for massively parallel processor design and utilization

NASA Technical Reports Server (NTRS)

Campbell, Lowell; Fellows, Michael R.

1990-01-01

This paper summarizes the author's advances in the design of dense processor networks. Within is reported a collection of recent constructions of dense symmetric networks that provide the largest know values for the number of nodes that can be placed in a network of a given degree and diameter. The constructions are in the range of current potential engineering significance and are based on groups of automorphisms of finite-dimensional vector spaces.

Astronautics Degrees for Space Industry

NASA Astrophysics Data System (ADS)

Gruntman, M.; Brodsky, R.; Erwin, D.; Kunc, J.

The Astronautics Program (http://astronautics.usc.edu) of the University of Southern California (USC) offers a full set of undergraduate and graduate degree programs in Aerospace Engineering with emphasis in Astronautics. The Bachelor of Science degree program in Astronautics combines basic science and engineering classes with specialized astronautics classes. The Master of Science degree program in Astronautics offers classes in various areas of space technology. The Certificate in Astronautics targets practicing engineers and scientists who enter space-related fields and/or who want to obtain training in specific space-related areas. Many specialized graduate classes are taught by adjunct faculty working at the leading space companies. The Master of Science degree and Certificate are available through the USC Distance Education Network (DEN). Today, the Internet allows us to reach students anywhere in the world through webcasting. The majority of our graduate students, as well as those pursuing the Certificate, work full time as engineers in the space industry and government research and development centers. The new world of distance learning presents new challenges and opens new opportunities. We show how the transformation of distance learning and particularly the introduction of webcasting transform organization of the program and class delivery. We will describe in detail the academic focus of the program, student reach, and structure of program components. Program development is illustrated by the student enrollment dynamics and related industrial trends; the lessons learned emphasize the importance of feedback from the students and from the space industry.

Preliminary crystallographic analysis of the oxidized form of a two mono-nuclear iron centres protein from Desulfovibrio desulfuricans ATCC 27774.

PubMed Central

Coelho, A. V.; Matias, P. M.; Carrondo, M. A.; Tavares, P.; Moura, J. J.; Moura, I.; Fülop, V.; Hajdu, J.; Le Gall, J.

1996-01-01

Crystals of the fully oxidized form of desulfoferrodoxin were obtained by vapor diffusion from a solution containing 20% PEG 4000, 0.1 M HEPES buffer, pH 7.5, and 0.2 M CaCl2. Trigonal and/or rectangular prisms could be obtained, depending on the temperature used for the crystal growth. Trigonal prisms belong to the rhombohedral space group R32, with a = 112.5 A and c = 63.2 A; rectangular prisms belong to the monoclinic space group C2, with a = 77.7 A, b = 80.9 A, c = 53.9 A, and beta = 98.1 degrees. The crystallographic asymmetric unit of the rhombohedral crystal form contains one molecule. There are two molecules in the asymmetric unit of the monoclinic form, in agreement with the self-rotation function. PMID:8762151

Structure and Magnetic Properties of a Mixed-Valence Heptanuclear Manganese Cluster.

PubMed

Abbati, Gian Luca; Cornia, Andrea; Fabretti, Antonio C.; Caneschi, Andrea; Gatteschi, Dante

1998-07-27

Two novel polynuclear manganese(II,III) complexes have been synthesized by exploiting controlled methanolysis. A one-pot reaction of MnCl(2), NaOMe, dibenzoylmethane (Hdbm), and O(2) in anhydrous methanol, followed by recrystallization from MeOH/CHCl(3) mixtures, afforded the alkoxomanganese complexes [Mn(7)(OMe)(12)(dbm)(6)].CHCl(3).14MeOH (2) and [Mn(2)(OMe)(2)(dbm)(4)] (3). Complex 2 crystallizes in trigonal space group R&thremacr; with a = 14.439(2) Å, alpha = 86.34(1) degrees, and Z = 1. Complex 3 crystallizes in triclinic space group P&onemacr; with a = 9.612(1) Å, b = 10.740(1) Å, c = 13.168(1) Å, alpha = 80.39(1) degrees, beta = 87.66(1) degrees, gamma = 83.57(1) degrees, and Z = 1. The solid-state structure of 2 comprises a [Mn(6)(OMe)(12)(dbm)(6)] "crown" with crystallographically imposed 6-fold symmetry plus a central manganese ion. The layered Mn/O core mimics a fragment of the manganese oxide mineral lithiophorite. Conductivity measurements confirmed the nonionic character of 2 and suggested a mixed-valence Mn(II)(3)Mn(III)(4) formulation. The metrical parameters of the core were analyzed with the aid of bond-valence sum calculations. The central ion is essentially a valence-trapped Mn(II) ion, whereas the average Mn-O distances for the manganese ions of the "crown" are consistent with the presence of two Mn(II) and four Mn(III) ions. However, (1)H NMR spectra in solution strongly support valence localization and suggest that the observed solid-state structure may be a result of static disorder effects. Magnetic susceptibility vs T and magnetization vs field data at low temperature are consistent with an S = (17)/(2) ground state. Complex 3 is a symmetric alkoxo-bridged dimer. The two high-spin Mn(III) ions are antiferromagnetically coupled with J = 0.28(4) cm(-)(1), g = 1.983(2), and D = -2.5(4) cm(-)(1).

Influence of Sulfur Metalation on the Accessibility of the Ni(II/I) Couple in [N,N'-Bis(2-mercaptoethyl)-1,5-diazacyclooctanato]nickel(II): Insight into the Redox Properties of [NiFe]-Hydrogenase.

PubMed

Musie, Ghezai; Farmer, Patrick J.; Tuntulani, Thawatchai; Reibenspies, Joseph H.; Darensbourg, Marcetta Y.

1996-04-10

A redox model study of [NiFe] hydrogenase has examined a series of five polymetallics based on the metalation of the dithiolate complex [1,5-bis(mercaptoethyl)-1,5-diazacyclooctane]Ni(II), Ni-1. Crystal structures of three polymetallics of the series have been reported earlier: [(Ni-1)(2)()Ni]Cl(2)(), [(Ni-1)(2)()FeCl(2)()](2)(), and [(Ni-1)(3)()(ZnCl)(2)()]Cl(2)(). Two are described here: [(Ni-1)(2)()Pd]Cl(2)().2H(2)()Ocrystallizes in the monoclinic system, space group P2(1)/c with cell constants a = 12.212(4) Å, b = 7.642(2) Å, c = 16.625(3) Å, beta = 107.69(2) degrees, V = 1443.230(0) Å(3), Z = 2, R = 0.051, and R(w) = 0.056. [(Ni-1)(2)()CoCl]PF(6)() crystallizes in the triclinic system, space group P&onemacr;, with cell constants a = 8.14(2) Å, b = 13.85(2) Å, c = 15.67(2) Å, alpha = 113.59(10) degrees, beta = 101.84(14) degrees, gamma = 94.0(2) degrees, V = 1561.620(0)Å(3), Z = 2, R = 0.072, and R(w) = 0.077. In all Ni-1 serves as a bidentate metallothiolate ligand with a "hinge" angle in the range 105-118 degrees and Ni-M distances of 2.7- 3.7 Å. The most accessible redox event is shown by EPR and electrochemistry to reside in the N(2)S(2)Ni unit and is the Ni(II/I) couple. Charge neutralization of the thiolate sulfurs by metalation can (dependent on the interacting metal) stabilize the Ni(I) state as efficiently as methylation forming a thioether. The implication of these results for the heterometallic active site of [NiFe]-hydrogenase as structured from Desulfovibrio gigas (Volbeda, A., et al. Nature, 1995, 373, 580), the generality of the Ni(&mgr;-SR)(2)M hinge structure, and a possible explanation for the unusual redox potentials are discussed.

The effect of crown/implant ratio and crown height space on stress distribution in unsplinted implant supporting restorations.

PubMed

Nissan, Joseph; Ghelfan, Oded; Gross, Ora; Priel, Ilan; Gross, Martin; Chaushu, Gavriel

2011-07-01

To measure the transfer of axial and nonaxial load in unsplinted fixed implant supported restoration with varying crown to implant (C/I) ratios and crown height space (CHS). A photoelastic block model was constructed. Three holes were drilled vertically in a straight line in the mid axis of the photoelastic model at predetermined locations to lengths of 12 mm. Three implants were inserted into the model. Two strain gauges were cemented onto the neck of each implant on the buccal and lingual aspects, which provided a simultaneous direct reading of strain. Four groups of cement retained restorations with C/I ratios of 1:1; 1:1.5; 1:1.75, and 1:2 were used. CHS were 10, 15, 17.5, and 20 mm, respectively. Fifteen static loadings were carried out simultaneously with 20 kg weights via a custom-built loading apparatus at 0 and 30 degrees to the vertical axis. Descriptive analysis consisted of mean and standard deviation of microstrain values for each group. Groups were compared by the use of the 1-way parametric analysis of variance. A P value of less than .05 was considered statistically significant. Occlusal force application at 30 degrees showed a statistically significant increase in both buccal (1,588 ± 150 vs 2,610.59 ± 150) and palatal (64.92 ± 7 vs 146.59 ± 15) microstrain values as C/I ratio increased from 1:1 to 1:1.5 (P < .001). Force application at 30 degrees in cases with C/I ratio of 1:1.75 and 1:2 resulted in fracture of the abutment screw followed by dislodgment of the crowns. Failures were noted at CHS >15 mm. CHS is more significant than the C/I ratio in assessing biomechanical-related detrimental effects. Prosthetic failure occurred at CHS ≥ 15 mm. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

X-ray structural studies and physicochemical characterization of (E)-6-(3,4-dimethoxyphenyl)-1-ethyl-4-mesitylimino-3-methyl- 3,4-dihydro-2(1H)-pyrimidinone polymorphs.

PubMed

Miyamae, A; Kitamura, S; Tada, T; Koda, S; Yasuda, T

1991-10-01

The polymorphism of (E)-6-(3,4-dimethoxyphenyl)-1-ethyl-4-mesitylimino-3-methyl-3,4-di hydro- 2(1 H)-pyrimidinone (FK664; 1) was characterized by using X-ray powder diffractometry, differential scanning calorimetry (DSC), and IR spectroscopy. Structures of two polymorphs (Forms A and B) were determined by X-ray crystallographic analysis. Form A crystallized in the monoclinic space group P2(1)/c, with a = 13.504(2), b = 6.733(1), c = 24.910(8) A, beta = 96.55(4) degrees, z = 4, and dcal = 1.203 g/cm3, while Form B crystallized in the same space group, with a = 8.067(2), b = 15.128(4), c = 18.657(4) A, beta = 102.34(3) degrees, z = 4, and dcal = 1.216 g/cm3. The conformational features of 1 were very similar between the two polymorphs. Compound 1, in both crystal forms, took an energetically reasonable conformation in three rigid planes, such as 2-pyrimidone, trimethylphenyl, and dimethoxyphenyl rings, but the molecules were packed in different ways between the two polymorphs. In the Form B crystal, a short contact was possible, to form pi-pi interactions between two dimethoxyphenyl groups related with the inversion center in the crystal lattice; this interaction seems to contribute to stabilizing the crystal structure of Form B. Both Forms A and B showed only one endothermic peak due to fusion at 115 and 140 degrees C, respectively, on the DSC thermograms; therefore, it is suggested that there are no transition points between the two polymorphs. The heats of fusion obtained from the DSC thermograms were 33.2(2) kJ/mol for Form A and 36.8(1) kJ/mol for Form B.(ABSTRACT TRUNCATED AT 250 WORDS)

A New Global Group Velocity Dataset for Constraining Crust and Upper Mantle Properties

NASA Astrophysics Data System (ADS)

Ma, Z.; Masters, G.; Laske, G.; Pasyanos, M. E.

2010-12-01

We are improving our CRUST2.0 to a new LITHO1.0 model, refining the nominal resolution to 1 degree and including lithospheric structure. The new model is constrained by many datasets, including very large datasets of surface wave group velocity built using a new, efficient measurement technique. This technique starts in a similar fashion to the traditional frequency-time analysis, but instead of making measurements for all frequencies for a single source-station pair, we apply cluster analysis to make measurements for all recordings for a single event at a single target frequency. By changing the nominal frequencies of the bandpass filter, we filter each trace until the centroid frequency of the band-passed spectrum matches the target frequency. We have processed all the LH data from IRIS (and some of the BH data from PASSCAL experiments and the POLARIS network) from 1976 to 2007. The Rayleigh wave group velocity data set is complete from 10mHz to 40mHz at increments of 2.5mHz. The data set has about 330000 measurements for 10 and 20mHz, 200000 for 30mHz and 110000 for 40mHz. We are also building a similar dataset for Love waves, though its size will be about half that of the Rayleigh wave dataset. The SMAD of the group arrival time difference between our global dataset and other more regional datasets is about 12 seconds for 20mHz, 9 seconds for 30mHz, and 7 seconds for 40mHz. Though the discrepancies are about twice as big as our measurement precision (estimated by looking at group arrival time differences between closely-spaced stations), it is still much smaller than the signal in the data (e.g., the group arrival time for 20mHz can differ from the prediction of a 1D Earth by over 250 seconds). The fact that there is no systematic bias between the datasets encourages us to combine them to improve coverage of some key areas. Group velocity maps inverted from the combined datasets show many interesting signals though the dominant signal is related to variations in crustal thickness. For 20mHz, group velocity perturbations from the global mean range from -25% to 11%, with a standard deviation of 4%. We adjust the smoothing of lateral structure in the inversion so that the error of the inferred group velocity is nearly uniform globally. For 20mHz, a 0.1% error in group velocity leads to resolution of features of dimension 9 degrees or less everywhere. The resolution in Eurasia is 5.5 degrees and in N. America is 4.5-5 degrees. For 30mHz, for the same 0.1% error, we can resolve structure of 10 degrees globally, 6.5 degrees for Eurasia and 5.5 degree for N. America.

A Statistical Physics Characterization of the Complex Systems Dynamics: Quantifying Complexity from Spatio-Temporal Interactions

PubMed Central

Koorehdavoudi, Hana; Bogdan, Paul

2016-01-01

Biological systems are frequently categorized as complex systems due to their capabilities of generating spatio-temporal structures from apparent random decisions. In spite of research on analyzing biological systems, we lack a quantifiable framework for measuring their complexity. To fill this gap, in this paper, we develop a new paradigm to study a collective group of N agents moving and interacting in a three-dimensional space. Our paradigm helps to identify the spatio-temporal states of the motion of the group and their associated transition probabilities. This framework enables the estimation of the free energy landscape corresponding to the identified states. Based on the energy landscape, we quantify missing information, emergence, self-organization and complexity for a collective motion. We show that the collective motion of the group of agents evolves to reach the most probable state with relatively lowest energy level and lowest missing information compared to other possible states. Our analysis demonstrates that the natural group of animals exhibit a higher degree of emergence, self-organization and complexity over time. Consequently, this algorithm can be integrated into new frameworks to engineer collective motions to achieve certain degrees of emergence, self-organization and complexity. PMID:27297496

An empirical examination of consumer effects across twenty degrees of latitude.

PubMed

Lavender, James T; Dafforn, Katherine A; Bishop, Melanie J; Johnston, Emma L

2017-09-01

The strength and importance of consumer effects are predicted to increase toward low latitudes, but this hypothesis has rarely been tested using a spatially consistent methodology. In a consumer-exclusion experiment spanning twenty degrees of latitude along the east Australian coast, the magnitude of consumer effects on sub-tidal sessile assemblage composition was not greater at low than high latitudes. Across caged and control assemblages, Shannon's diversity, Pielou's evenness, and richness of functional groups decreased with increasing latitude, but the magnitude of consumer effects on these metrics did not display consistent latitudinal gradients. Instead, latitudinal gradients in consumer effects were apparent for individual functional groups. Solitary ascidians displayed the pattern consistent with predictions of greater direct effects of predators at low than high latitude. As consumers reduced the biomass of this and other competitive dominants, groups less prone to predation (e.g., hydroids, various groups of bryozoans) were able to take advantage of freed space in the presence of consumers and show increased abundances there. This large-scale empirical study demonstrates the complexity of species interactions, and the failure of assemblage-level metrics to adequately capture consumer effects over large spatial gradients. © 2017 by the Ecological Society of America.

A Statistical Physics Characterization of the Complex Systems Dynamics: Quantifying Complexity from Spatio-Temporal Interactions

NASA Astrophysics Data System (ADS)

Koorehdavoudi, Hana; Bogdan, Paul

2016-06-01

Biological systems are frequently categorized as complex systems due to their capabilities of generating spatio-temporal structures from apparent random decisions. In spite of research on analyzing biological systems, we lack a quantifiable framework for measuring their complexity. To fill this gap, in this paper, we develop a new paradigm to study a collective group of N agents moving and interacting in a three-dimensional space. Our paradigm helps to identify the spatio-temporal states of the motion of the group and their associated transition probabilities. This framework enables the estimation of the free energy landscape corresponding to the identified states. Based on the energy landscape, we quantify missing information, emergence, self-organization and complexity for a collective motion. We show that the collective motion of the group of agents evolves to reach the most probable state with relatively lowest energy level and lowest missing information compared to other possible states. Our analysis demonstrates that the natural group of animals exhibit a higher degree of emergence, self-organization and complexity over time. Consequently, this algorithm can be integrated into new frameworks to engineer collective motions to achieve certain degrees of emergence, self-organization and complexity.

Hamiltonian Anomalies from Extended Field Theories

NASA Astrophysics Data System (ADS)

Monnier, Samuel

2015-09-01

We develop a proposal by Freed to see anomalous field theories as relative field theories, namely field theories taking value in a field theory in one dimension higher, the anomaly field theory. We show that when the anomaly field theory is extended down to codimension 2, familiar facts about Hamiltonian anomalies can be naturally recovered, such as the fact that the anomalous symmetry group admits only a projective representation on the Hilbert space, or that the latter is really an abelian bundle gerbe over the moduli space. We include in the discussion the case of non-invertible anomaly field theories, which is relevant to six-dimensional (2, 0) superconformal theories. In this case, we show that the Hamiltonian anomaly is characterized by a degree 2 non-abelian group cohomology class, associated to the non-abelian gerbe playing the role of the state space of the anomalous theory. We construct Dai-Freed theories, governing the anomalies of chiral fermionic theories, and Wess-Zumino theories, governing the anomalies of Wess-Zumino terms and self-dual field theories, as extended field theories down to codimension 2.

Structural and functional properties of spatially embedded scale-free networks.

PubMed

Emmerich, Thorsten; Bunde, Armin; Havlin, Shlomo

2014-06-01

Scale-free networks have been studied mostly as non-spatially embedded systems. However, in many realistic cases, they are spatially embedded and these constraints should be considered. Here, we study the structural and functional properties of a model of scale-free (SF) spatially embedded networks. In our model, both the degree and the length of links follow power law distributions as found in many real networks. We show that not all SF networks can be embedded in space and that the largest degree of a node in the network is usually smaller than in nonembedded SF networks. Moreover, the spatial constraints (each node has only few neighboring nodes) introduce degree-degree anticorrelations (disassortativity) since two high degree nodes cannot stay close in space. We also find significant effects of space embedding on the hopping distances (chemical distance) and the vulnerability of the networks.

Disordered crystals from first principles I: Quantifying the configuration space

NASA Astrophysics Data System (ADS)

Kühne, Thomas D.; Prodan, Emil

2018-04-01

This work represents the first chapter of a project on the foundations of first-principle calculations of the electron transport in crystals at finite temperatures. We are interested in the range of temperatures, where most electronic components operate, that is, room temperature and above. The aim is a predictive first-principle formalism that combines ab-initio molecular dynamics and a finite-temperature Kubo-formula for homogeneous thermodynamic phases. The input for this formula is the ergodic dynamical system (Ω , G , dP) defining the thermodynamic crystalline phase, where Ω is the configuration space for the atomic degrees of freedom, G is the space group acting on Ω and dP is the ergodic Gibbs measure relative to the G-action. The present work develops an algorithmic method for quantifying (Ω , G , dP) from first principles. Using the silicon crystal as a working example, we find the Gibbs measure to be extremely well characterized by a multivariate normal distribution, which can be quantified using a small number of parameters. The latter are computed at various temperatures and communicated in the form of a table. Using this table, one can generate large and accurate thermally-disordered atomic configurations to serve, for example, as input for subsequent simulations of the electronic degrees of freedom.

SpeedyTime_7-Minus_Eighty_Degrees_Laboratory_Freezer_for_ ISS

NASA Image and Video Library

2017-08-23

SpeedyTime 7 – Minus Eighty Degrees Laboratory Freezer for ISS Cutting-edge science is on the daily menu on board the International Space Station, but where do the astronauts store their lab results before they’re shipped back to Earth? In one of a dozen large freezers, of course: in this SpeedyTime segment, Expedition 52 flight engineer Jack Fischer shines a light on the MELFI, Minus Eighty Degrees Laboratory Freezer for ISS. _______________________________________ FOLLOW THE SPACE STATION! Twitter: https://twitter.com/Space_Station Facebook: https://www.facebook.com/ISS Instagram: https://instagram.com/iss/

Integrability and nonintegrability of quantum systems. II. Dynamics in quantum phase space

NASA Astrophysics Data System (ADS)

Zhang, Wei-Min; Feng, Da Hsuan; Yuan, Jian-Min

1990-12-01

Based on the concepts of integrability and nonintegrability of a quantum system presented in a previous paper [Zhang, Feng, Yuan, and Wang, Phys. Rev. A 40, 438 (1989)], a realization of the dynamics in the quantum phase space is now presented. For a quantum system with dynamical group scrG and in one of its unitary irreducible-representation carrier spaces gerhΛ, the quantum phase space is a 2MΛ-dimensional topological space, where MΛ is the quantum-dynamical degrees of freedom. This quantum phase space is isomorphic to a coset space scrG/scrH via the unitary exponential mapping of the elementary excitation operator subspace of scrg (algebra of scrG), where scrH (⊂scrG) is the maximal stability subgroup of a fixed state in gerhΛ. The phase-space representation of the system is realized on scrG/scrH, and its classical analogy can be obtained naturally. It is also shown that there is consistency between quantum and classical integrability. Finally, a general algorithm for seeking the manifestation of ``quantum chaos'' via the classical analogy is provided. Illustrations of this formulation in several important quantum systems are presented.

Design features that affect the maneuverability of wheelchairs and scooters.

PubMed

Koontz, Alicia M; Brindle, Eric D; Kankipati, Padmaja; Feathers, David; Cooper, Rory A

2010-05-01

To determine the minimum space required for wheeled mobility device users to perform 4 maneuverability tasks and to investigate the impact of selected design attributes on space. Case series. University laboratory, Veterans Affairs research facility, vocational training center, and a national wheelchair sport event. The sample of convenience included manual wheelchair (MWC; n=109), power wheelchair (PWC; n=100), and scooter users (n=14). A mock environment was constructed to create passageways to form an L-turn, 360 degrees -turn in place, and a U-turn with and without a barrier. Passageway openings were increased in 5-cm increments until the user could successfully perform each task without hitting the walls. Structural dimensions of the device and user were collected using an electromechanical probe. Mobility devices were grouped into categories based on design features and compared using 1-way analysis of variance and post hoc pairwise Bonferroni-corrected tests. Minimum passageway widths for the 4 maneuverability tasks. Ultralight MWCs with rear axles posterior to the shoulder had the shortest lengths and required the least amount of space compared with all other types of MWCs (P<.05). Mid-wheel-drive PWCs required the least space for the 360 degrees -turn in place compared with front-wheel-drive and rear-wheel-drive PWCs (P<.01) but performed equally as well as front-wheel-drive models on all other turning tasks. PWCs with seat functions required more space to perform the tasks. Between 10% and 100% of users would not be able to maneuver in spaces that meet current Accessibility Guidelines for Buildings and Facilities specifications. This study provides data that can be used to support wheelchair prescription and home modifications and to update standards to improve the accessibility of public areas.

Modal space three-state feedback control for electro-hydraulic servo plane redundant driving mechanism with eccentric load decoupling.

PubMed

Zhao, Jinsong; Wang, Zhipeng; Zhang, Chuanbi; Yang, Chifu; Bai, Wenjie; Zhao, Zining

2018-06-01

The shaking table based on electro-hydraulic servo parallel mechanism has the advantage of strong carrying capacity. However, the strong coupling caused by the eccentric load not only affects the degree of freedom space control precision, but also brings trouble to the system control. A novel decoupling control strategy is proposed, which is based on modal space to solve the coupling problem for parallel mechanism with eccentric load. The phenomenon of strong dynamic coupling among degree of freedom space is described by experiments, and its influence on control design is discussed. Considering the particularity of plane motion, the dynamic model is built by Lagrangian method to avoid complex calculations. The dynamic equations of the coupling physical space are transformed into the dynamic equations of the decoupling modal space by using the weighted orthogonality of the modal main mode with respect to mass matrix and stiffness matrix. In the modal space, the adjustments of the modal channels are independent of each other. Moreover, the paper discusses identical closed-loop dynamic characteristics of modal channels, which will realize decoupling for degree of freedom space, thus a modal space three-state feedback control is proposed to expand the frequency bandwidth of each modal channel for ensuring their near-identical responses in a larger frequency range. Experimental results show that the concept of modal space three-state feedback control proposed in this paper can effectively reduce the strong coupling problem of degree of freedom space channels, which verify the effectiveness of the proposed model space state feedback control strategy for improving the control performance of the electro-hydraulic servo plane redundant driving mechanism. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Echocardiograms during six hours of bedrest at head-down and head-up tilt and during space flight

NASA Technical Reports Server (NTRS)

Lathers, C. M.; Riddle, J. M.; Mulvagh, S. L.; Mukai, C.; Diamandis, P. H.; Dussack, L. G.; Bungo, M. W.; Charles, J. B.

1993-01-01

Left ventricular end-diastolic volume increased after 4 1/2 to 6 hours of space flight, but was significantly decreased after 5 to 6 days of space flight. To determine the role of acute gravitational effects in this phenomenon, responses to a 6-hour bedrest model of 0 gravity (G; 5 degrees head-down tilt) were compared with those of fractional gravity loads of 1/6 G, 1/3 G, and 2/3 G by using head-up tilts of 10 degrees, 20 degrees, and 42 degrees, respectively. On 4 different days, six healthy male subjects were tilted at one of the four angles for 6 hours. Cardiac dimensions and volumes were determined from two-dimensional and M-mode echocardiograms in the left lateral decubitus position at control (0), 2, 4, and 6 hours. Stroke volume decreased with time (P < .05) for all tilt angles when compared with control. Ejection fraction (EF) at -5 degrees was greater than at +20 degrees and +42 degrees (not significant); EF at +10 degrees was greater than at +42 degrees (not significant). For the tilt angles of -5 degrees, +10 degrees, and +20 degrees, mean heart rate decreased during the first 2 hours, and returned to control or was slightly elevated above control (+20 degrees) by 6 hours (not significant). At the +42 degrees angle of tilt, heart rate was increased above control at hours 2, 4, and 6. There were no significant differences in cardiac output at any time point for any tilt angle.(ABSTRACT TRUNCATED AT 250 WORDS).

New-type active vibration isolation system with laser interferometer and piezoelectric displacement transducer

NASA Astrophysics Data System (ADS)

Lu, Boyin; Zhao, Meirong

1994-09-01

A new-type active vibration isolation system is developed for ultra-precision measuring system. It is composed of three sets of 3D Laser interferometer transducer and six groups of piezoelectric displacement executor to constrain six degrees of space movement and to realize real-time compensation of vibration. The active vibration isolation system can effectively eliminate low-frequency vibrations. Combined with passive vibration isolation system, it gives better vibration isolation effect.

The healing effect of electrolytic-reduction ion water on burn wounds.

PubMed

Okajima, Masahiro; Shimokawa, Ken-ichi; Ishii, Fumiyoshi

2010-02-01

We prepared a lotion using electrolytic-reduction ion water (ERI), and evaluated the healing effects of this lotion (ERI lotion) on burn wounds. Third degree burn wounds were induced in the mouse dorsal skin, and ERI lotion or physiological salt (PS) lotion was applied to the wounds from immediately after injury [ERI (+) group and ERI (-) group as a control group, respectively]. The burn wound area was measured, and its serial changes were evaluated. In addition, histological examination of the burn wound site (on day 3) was performed. Comparison of the ERI (+) and (-) groups showed a significant reduction in the burn wound area in the former. Histological examination confirmed many interstitial spaces, blood vessels, and lymphatic vessels in the subcutaneous tissue in the ERI (-) compared with the ERI (+) group. These results suggest the promotion of burn wound healing by ERI lotion.

The Huygens Descent Trajectory Working Group and the Reconstruction of the Huygens Probe Entry and Descent Trajectory at Titan

NASA Astrophysics Data System (ADS)

Atkinson, David H.; Kazeminejad, Bobby; Lebreton, Jean-Pierre

2015-04-01

Cassini/Huygens, a flagship mission to explore the rings, atmosphere, magnetic field, and moons that make up the Saturn system, is a joint endeavor of NASA, the European Space Agency, and Agenzia Spaziale Italiana. Comprising two spacecraft - a Saturn orbiter built by NASA and a Titan entry/descent probe built by the European Space Agency - Cassini/Huygens was launched in October 1997 and arrived at Saturn in 2004. The Huygens probe parachuted to the surface of Titan in January 2005. During the descent, six science instruments provided measurements of Titan's atmosphere, clouds, and winds, and photographed Titan's surface. It was recognized early in the Huygens program that to correctly interpret and correlate results from the probe science experiments and to provide a reference set of data for ground truth calibration of the Cassini orbiter remote sensing observations, an accurate reconstruction of the probe entry and descent trajectory and surface landing location would be necessary. The Huygens Descent Trajectory Working Group (DTWG) was chartered in 1996 as a subgroup of the Huygens Science Working Team. With membership comprising representatives from all the probe engineering and instrument teams as well as representatives of industry and the Cassini and Huygens Project Scientists, the DTWG presented an organizational framework within which instrument data was shared, the entry and descent trajectory reconstruction implemented, and the trajectory reconstruction efficiently disseminated. The primary goal of the Descent Trajectory Working Group was to develop retrieval methodologies for the probe descent trajectory reconstruction from the entry interface altitude of 1270 km to the surface using navigation data, and engineering and science data acquired by the instruments on the Huygens Probe, and to provide a reconstruction of the Huygens probe trajectory from entry to the surface of Titan that is maximally consistent with all available engineering and science data sets. The official project entry and descent trajectory reconstruction effort was published by the DTWG in 2007. A revised descent trajectory was released in 2010 that accounts for updated measurements of Titan's pole coordinates derived from radar images of Titan taken during Cassini flybys after 2007. The effect of the updated pole positions on Huygens is a southward shift of the trajectory by about 0.3 degrees with a much smaller effect of less than 0.01 degree in the zonal (west to east) direction. The revised Huygens landing coordinates of 192.335 degrees West and 10.573 degrees South with longitude and latitude residuals of respectively 0.035 degrees and 0.007 degrees, respectively, are in excellent agreement with results of recent landing site investigations using visual and radar images from the Cassini VIMS instrument. Acknowledgements *J.-P.L's work was performed while at ESA/ESTEC. DA and BK would like to express appreciation to the European Space Agency's Research and Scientific Support Department for funding the Descent Trajectory Working Group. The work of the Descent Trajectory Working Group would not have been possible without the dedicated efforts of all the Huygens principal investigators and their teams, and the science and engineering data provided from each experiment team, including M. Fulchignoni and the HASI Team, H. Niemann and the GCMS Team, J. Zarnecki and the SSP Team, M. Tomasko and the DISR Team, M. Bird and the DWE Team, and G. Israel and the ACP Team. Additionally, special thanks for many years of support to D.L. Matson, R.T. Mitchell, M. Pérez-Ayúcar, O. Witasse; J. Jones, D. Roth, N. Strange on the Cassini Navigation Team at JPL; A.-M. Schipper and P. Couzin at Thales Alenia; C. Sollazzo, D. Salt, J. Wheadon and S. Standley from the Huygens Ops Team; and R. Trautner and H. Svedhem on the Radar Team at ESTEC.

Crystal structure of carnidazole form II from synchrotron X-ray powder diffraction: structural comparison with form I, the hydrated form and the low energy conformations in vacuo.

PubMed

de Armas, Héctor Novoa; Peeters, Oswald M; Blaton, Norbert; Van den Mooter, Guy; De Ridder, Dirk J A; Schenk, Henk

2006-10-01

The crystal structure of carnidazole form II, O-methyl [2-(2-methyl-5-nitro-1H-imidazole-1-yl)ethyl]thiocarbamate, has been determined using synchrotron X-ray powder diffraction in combination with simulated annealing and whole profile pattern matching, and refined by the Rietveld method. For structure solution, 12 degrees of freedom were defined: one motion group and six torsions. Form II crystallizes in space group P2(1)/n, Z=4, with unit cell parameters after Rietveld refinement: a=13.915(4), b=8.095(2), c=10.649(3) A, beta=110.83(1) degrees, and V=1121.1(5) A3. The two polymorphic forms, as well as the hydrate, crystallize in the monoclinic space group P2(1)/n having four molecules in the cell. In form II, the molecules are held together by forming two infinite zig-zag chains via hydrogen bonds of the type N--H...N, the same pattern as in form I. A conformational study of carnidazole, at semiempirical PM3 level, was performed using stochastic approaches based on modification of the flexible torsion angles. The values of the torsion angles for the molecules of the two polymorphic forms and the hydrate of carnidazole are compared to those obtained from the conformational search. Form I and form II are enantiotropic polymorphic pairs this agrees with the fact that the two forms are conformational polymorphs. Copyright (c) 2006 Wiley-Liss, Inc. and the American Pharmacists Association

Doubled lattice Chern-Simons-Yang-Mills theories with discrete gauge group

NASA Astrophysics Data System (ADS)

Caspar, S.; Mesterházy, D.; Olesen, T. Z.; Vlasii, N. D.; Wiese, U.-J.

2016-11-01

We construct doubled lattice Chern-Simons-Yang-Mills theories with discrete gauge group G in the Hamiltonian formulation. Here, these theories are considered on a square spatial lattice and the fundamental degrees of freedom are defined on pairs of links from the direct lattice and its dual, respectively. This provides a natural lattice construction for topologically-massive gauge theories, which are invariant under parity and time-reversal symmetry. After defining the building blocks of the doubled theories, paying special attention to the realization of gauge transformations on quantum states, we examine the dynamics in the group space of a single cross, which is spanned by a single link and its dual. The dynamics is governed by the single-cross electric Hamiltonian and admits a simple quantum mechanical analogy to the problem of a charged particle moving on a discrete space affected by an abstract electromagnetic potential. Such a particle might accumulate a phase shift equivalent to an Aharonov-Bohm phase, which is manifested in the doubled theory in terms of a nontrivial ground-state degeneracy on a single cross. We discuss several examples of these doubled theories with different gauge groups including the cyclic group Z(k) ⊂ U(1) , the symmetric group S3 ⊂ O(2) , the binary dihedral (or quaternion) group D¯2 ⊂ SU(2) , and the finite group Δ(27) ⊂ SU(3) . In each case the spectrum of the single-cross electric Hamiltonian is determined exactly. We examine the nature of the low-lying excited states in the full Hilbert space, and emphasize the role of the center symmetry for the confinement of charges. Whether the investigated doubled models admit a non-Abelian topological state which allows for fault-tolerant quantum computation will be addressed in a future publication.

Antiradiation Vaccine: Technology Development- Radiation Tolerance,Prophylaxis, Prevention And Treatment Of Clinical Presentation After Heavy Ion Irradiation.

NASA Astrophysics Data System (ADS)

Popov, Dmitri; Maliev, Slava; Jones, Jeffrey

Introduction: Research in the field of biological effects of heavy charged particles is necessary for both heavy-ion therapy (hadrontherapy) and protection from the exposure to galactic cosmic radiation in long-term manned space missions.[Durante M. 2004] In future crew of long-term manned missions could operate in exremely high hadronic radiation areas of space and will not survive without effective radiation protection. An Antiradiation Vaccine (AV) must be an important part of a countermeasures regimen for efficient radiation protection purposes of austronauts-cosmonauts-taukonauts: immune-prophylaxis and immune-therapy of acute radiation toxic syndromes developed after heavy ion irradiation. New technology developed (AV) for the purposes of radiological protection and improvement of radiation tolerance and it is quite important to create protective immune active status which prevent toxic reactions inside a human body irradiated by high energy hadrons.[Maliev V. et al. 2006, Popov D. et al.2008]. High energy hadrons produce a variety of secondary particles which play an important role in the energy deposition process, and characterise their radiation qualities [Sato T. et al. 2003] Antiradiation Vaccine with specific immune-prophylaxis by an anti-radiation vaccine should be an important part of medical management for long term space missions. Methods and experiments: 1. Antiradiation vaccine preparation standard, mixture of toxoid form of Radiation Toxins [SRD-group] which include Cerebrovascular RT Neurotoxin, Cardiovascular RT Neurotoxin, Gastrointestinal RT Neurotoxin, Hematopoietic RT Hematotoxin. Radiation Toxins of Radiation Determinant Group isolated from the central lymph of gamma-irradiated animals with Cerebrovascular, Cardiovascular, Gastro-intestinal, Hematopoietic forms of ARS. Devices for radiation are "Panorama", "Puma". 2. Heavy ion exposure was accomplished at Department of Research Institute of Nuclear Physics, Dubna, Russia. The heavy ions irradiation was generated in heavy ion (Fe56) accelerator - UTI. Heavy Ion linear transfer energy - 2000- 2600 KeV -mkm, 600 MeV -92U. Absorbed Dose - 3820 Rad. Experimental Design: Rabbits from all groups were irradiated by heavy ion accelerator. Group A: control-10 rabbits; Group B: placebo-5 rabbits; Group C: Radioprotectant Cystamine (50 mg-kg)-5 rabbits, 15 minutes before irradiation - 5 rabbits; Group D: Radioprotectant Gammafos (Amifostine 400mg -kg ) - 5 rabbits; Group E: Antiradiation Vaccine: subcutaneus administration or IM - 2 ml of active substance, 14 days before irradiation Results: Group A 100% mortality within two hours after heavy ion irradiation with clinical symptoms of Acute Cerebro- and Cardio-Vascular Radiation syndromes. Group B 100% mortality within 15 hours following irradiation. Group C 100% mortality within 14-15 hours after irradiation. Group D 100% mortality within 15-16 hours after irradiation. In groups A- D registered the development of acute radiation cerebrovascular and cardiovascular syndromes and also extensive burns. of skin produced rapid death. Group E -100% mortality in 280-290 hours (12 days) following heavy ion irradiation with animals exhibiting a combination or individual forms of Acute Cerebrovascular, Cardiovascular, and Gastrointestinal forms and focal skin burns. Discussion Antiradiation vaccine and immune-prophylaxis is an effective method of neutralization of Radiation Toxins. Vaccination before irradiation extended survival time after irradiation with heavy ions from two hours up to 300 hours. Clinical signs, clinical features, symptoms were somewhat attenuated. Degree of clinical forms of Acute Radiation Syndromes were diminished in their clinical manifestation and severity. Groups A-D demonstrated extremely severe level of Cerebrovascular and Cardiovascular forms of Acute Radiation Syndromes and lethality 100% was registered in short time after irradiation. Radiation induced burns in this groups (with Cutaneous sub-syndrome of ARS - Degree 4, that diffuse deep into soft tissues with extensive and total dysfunction and muscle involvement developed. Animals from group E - Radioprotectant Antiradiation Vaccine demonstrated later development of moderate-severe form forms of Cerebrovascular and Cardiovascular forms of ARS and survival time of irradiated animals was prolonged. Cutaneous sub-syndrome developed in Degree 3 or Degree 2-3. Our results have demonstrated potential radioprotection efficacy of immune-prophylaxis with Antiradiation Vaccine against high doses heavy ion irradiation.

Sleep-wake differences in scaling behavior of the human heartbeat: analysis of terrestrial and long-term space flight data

NASA Technical Reports Server (NTRS)

Bunde, A.; Amaral, L. A.; Havlin, S.; Fritsch-Yelle, J.; Baevsky, R. M.; Stanley, H. E.; Goldberger, A. L.

1999-01-01

We compare scaling properties of the cardiac dynamics during sleep and wake periods for healthy individuals, cosmonauts during orbital flight, and subjects with severe heart disease. For all three groups, we find a greater degree of anticorrelation in the heartbeat fluctuations during sleep compared to wake periods. The sleep-wake difference in the scaling exponents for the three groups is comparable to the difference between healthy and diseased individuals. The observed scaling differences are not accounted for simply by different levels of activity, but appear related to intrinsic changes in the neuroautonomic control of the heartbeat.

NASA's James Webb Space Telescope Science Instruments Begin Final Super Cold Test at Goddard

NASA Image and Video Library

2017-12-08

At NASA's James Webb Space Telescope's final destination in space, one million miles away from Earth, it will operate at incredibly cold temperatures of -387 degrees Fahrenheit, or 40 degrees Kelvin. This is 260 degrees Fahrenheit colder than any place on the Earth’s surface has ever been. So first, this final super cold test at Goddard will prepare the Integrated Science Instrument Module (ISIM), or the “heart” of the telescope, for space. Read more: go.nasa.gov/1KFPwJG Credit: NASA/Goddard/Chris Gunn NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Effect of timing and method of post space preparation on sealing ability of remaining root filling material: in vitro microbiological study.

PubMed

Grecca, Fabiana Soares; Rosa, Angela Rezende Gomes; Gomes, Maximiliano Schünke; Parolo, Clarissa Fatturi; Bemfica, Jules Renan Dutra; Frasca, Luis Carlos da Fontoura; Maltz, Marisa

2009-10-01

To evaluate the effect of timing (immediate versus delayed) and technique of post space preparation on the ability of the residual root canal obturation to prevent coronal bacterial leakage. Sixty-six single-rooted teeth were decoronated at the cementoenamel junction. The canals were prepared according to a step-back technique and were filled with thermoplasticized gutta-percha and AH Plus endodontic sealer (Dentsply De Trey). The root segments were randomly assigned to 8 groups. The positive controls (n = 3) were instrumented but not obturated. The negative controls (n = 3) were instrumented, obturated and sealed with Cavit (3M ESPE). In the other 6 groups (n = 10 each), the post space was prepared either immediately after obturation or 7 days later using LA Axxess burs (SybronEndo) (groups 1 and 2), heated pluggers (groups 3 and 4) or solvent delivered with a hand file (groups 5 and 6). The external surface of all roots was rendered waterproof with nail varnish. Custom-made dual-chamber devices were used to evaluate leakage. The coronal third of the prepared root canal was kept in contact with artificial saliva contaminated with Enterococcus faecalis, and the root apex was submerged in tryptic soy agar medium. The root assemblies were stored at 37 degrees C and were monitored daily over a 90-day period. The occurrence of turbidity in the medium was deemed to indicate bacterial leakage, from which failure of the seal was inferred. Throughout the experimental period, there was no significant difference (p = 0.094) among the preparation techniques, either immediate or delayed, in terms of bacterial leakage. Immediate and delayed post space preparation yielded similar outcomes in terms of the canal seal. Regardless of the timing and the technique of post space preparation, coronal bacterial leakage occurred over time.

Wide-angle Optical Telescope for the EUSO Experiments

NASA Technical Reports Server (NTRS)

Hillman, L. W.; Takahaski, Y.; Zuccaro, A.; Lamb, D.; Pitalo, K.; Lopado, A.; Keys, A.

2003-01-01

Future spacebased air shower experiments, including the planned Extreme Universe Space Observatory (EUSO) mission, require a wide-angle telescope in the near-UV wavelengths 330 - 400 nm. Widest possible target aperture of earth's atmosphere, such as greater than 10(exp 5) square kilometers sr, can be viewed within the field-of-view of 30 degrees from space. EUSO's optical design is required to be compact, being constrained by the allocated mass and diameter for use in space. Two doublesided Fresnel lenses with 2.5-m diameter are chosen for the baseline design. It satisfies the imaging resolution of 0.1 degree over the 30-degree field of view.

Implications of privacy needs and interpersonal distancing mechanisms for space station design

NASA Technical Reports Server (NTRS)

Harrison, A. A.; Sommer, R.; Struthers, N.; Hoyt, K.

1985-01-01

Privacy needs, or the need of people to regulate their degree of contact with one another, and interpersonal distancing mechanisms, which serve to satisfy these needs, are common in all cultures. Isolation, confinement, and other conditions accociated with space flight may at once accentuate privacy needs and limit the availability of certain common interpersonal contact. Loneliness occurs when people have less contact with one another than they desire. Crowding occurs when people have more contact with one another than they desire. Crowding, which is considered the greater threat to members of isolated and confined groups, can contribute to stress, a low quality of life, and poor performance. Drawing on the general literature on privacy, personal space, and interpersonal distancing, and on specialized literature on life aboard spacecraft and in spacecraft-analogous environments, a quantitative model for understanding privacy, interpersonal distancing, loneliness, and crowding was developed and the practical implications of this model for space station design were traced.

Space Weather and the State of Cardiovascular System of a Healthy Human Being

NASA Astrophysics Data System (ADS)

Samsonov, S. N.; Manykina, V. I.; Krymsky, G. F.; Petrova, P. G.; Palshina, A. M.; Vishnevsky, V. V.

The term "space weather" characterizes a state of the near-Earth environmental space. An organism of human being represents an open system so the change of conditions in the environment including the near-Earth environmental space influences the health state of a human being.In recent years many works devoted to the effect of space weather on the life on the Earth, and the degree of such effect has been represented from a zero-order up to apocalypse. To reveal a real effect of space weather on the health of human being the international Russian- Ukrainian experiment "Geliomed" is carried out since 2005 (http://geliomed.immsp.kiev.ua) [Vishnevsky et al., 2009]. The analysis of observational set of data has allowed to show a synchronism and globality of such effect (simultaneous manifestation of space weather parameters in a state of cardiovascular system of volunteer groups removed from each other at a distance over 6000 km). The response of volunteer' cardiovascular system to the changes of space weather parameters were observed even at insignificant values of the Earth's geomagnetic field. But even at very considerable disturbances of space weather parameters a human being healthy did not feel painful symptoms though measurements of objective physiological indices showed their changes.

Preliminary Evaluation of the Pathomechanisms of Dysphagia After Occipitospinal Fusion: Kinematic Analysis by Videofluoroscopic Swallowing Study.

PubMed

Kaneyama, Shuichi; Sumi, Masatoshi; Takabatake, Masato; Kasahara, Koichi; Kanemura, Aritetsu; Koh, Akihiro; Hirata, Hiroaki

2016-12-01

Kinematic analysis of swallowing function using videofluoroscopic swallowing study (VFSS). The aims of this study were to analyze swallowing process in the patients who underwent occipitospinal fusion (OSF) and elucidate the pathomechanism of dysphagia after OSF. Although several hypotheses about the pathomechanisms of dysphagia after OSF were suggested, there has been little tangible evidence to support these hypotheses since these hypotheses were based on the analysis of static radiogram or CT. Considering that swallowing is a compositive motion of oropharyngeal structures, the etiology of postoperative dysphagia should be investigated through kinematic approaches. Each four patients with or without postoperative dysphagia (group D and N, respectively) participated in this study. For VFSS, all patients were monitored to swallow 5-mL diluted barium solution by fluoroscopy, and then dynamic passing pattern of the barium solution was analyzed. Additionally, O-C2 angle (O-C2A) was measured for the assessment of craniocervical alignment. O-C2A in group D was -7.5 degrees, which was relatively smaller than 10.3 degrees in group N (P = 0.07). In group D, all cases presented smooth medium passing without any obstruction at the upper cervical level regardless of O-C2A, whereas the obstruction to the passage of medium was detected at the apex of mid-lower cervical ocurvature, where the anterior protrusion of mid-lower cervical spine compressed directly the pharyngeal space. In group N, all cases showed smooth passing of medium through the whole process of swallowing. This study presented that postoperative dysphagia did not occur at the upper cervical level even though there was smaller angle of O-C2A and demonstrated the narrowing of the oropharyngeal space towing to direct compression by the anterior protrusion of mid-lower cervical spine was the etiology of dysphagia after OSF. Therefore, surgeon should pay attention to the alignment of mid-cervical spine as well as craniocervical junction during OSF. 4.

Implementation of Wireless and Intelligent Sensor Technologies in the Propulsion Test Environment

NASA Technical Reports Server (NTRS)

Solano, Wanda M.; Junell, Justin C.; Shumard, Kenneth

2003-01-01

From the first Saturn V rocket booster (S-II-T) testing in 1966 and the routine Space Shuttle Main Engine (SSME) testing beginning in 1975, to more recent test programs such as the X-33 Aerospike Engine, the Integrated Powerhead Development (IPD) program, and the Hybrid Sounding Rocket (HYSR), Stennis Space Center (SSC) continues to be a premier location for conducting large-scale propulsion testing. Central to each test program is the capability for sensor systems to deliver reliable measurements and high quality data, while also providing a means to monitor the test stand area to the highest degree of safety and sustainability. As part of an on-going effort to enhance the testing capabilities of Stennis Space Center, the Test Technology and Development group is developing and applying a number of wireless and intelligent sensor technologies in ways that are new to the test existing test environment.

Six degree of freedom active vibration damping for space application

NASA Technical Reports Server (NTRS)

Haynes, Leonard S.

1993-01-01

Work performed during the period 1 Jan. - 31 Mar. 1993 on six degree of freedom active vibration damping for space application is presented. A performance and cost report is included. Topics covered include: actuator testing; mechanical amplifier design; and neural network control system development and experimental evaluation.

Comparison of cardiovascular function during the early hours of bed rest and space flight

NASA Technical Reports Server (NTRS)

Lathers, C. M.; Charles, J. B.

1994-01-01

This paper reviews the cardiovascular responses of six healthy male subjects to 6 hours in a 5 degrees head-down bed rest model of weightlessness, and compares these responses to those obtained when subjects were positioned in head-up tilts of 10 degrees, 20 degrees, and 42 degrees, simulating 1/6, 1/3, and 2/3 G, respectively. Thoracic fluid index, cardiac output, stroke volume, and peak flow were measured using impedance cardiography. Cardiac dimensions and volumes were determined from two-dimensional guided M-mode echocardiograms in the left lateral decubitus position at 0, 2, 4, and 6 hours. Cardiovascular response to a stand test were compared before and after bed rest. The impedance values were related to tilt angle for the first 2 hours of tilt; however, after 3 hours, at all four angles, values began to converge, indicating that cardiovascular homeostatic mechanisms seek a common adapted state, regardless of effective gravity level (tilt angle) up to 2/3 G. Echocardiography revealed that left ventricular end-diastolic and end-systolic volume, stroke volume, ejection fraction, heart rate, and cardiac output had returned to control values by hour 6 for all tilt angles. The lack of a significant immediate change in left ventricular end-diastolic volume, despite decrements in stroke volume (P < .05) and heart rate (not significant), indicates that multiple factors may play a role in the adaptation to simulated hypogravity. The echocardiography data indicated that no angle of tilt, whether head-down or head-up for 4 to 6 hours, mimicked exactly the changes in cardiovascular function recorded after 4 to 6 hours of space flight. Changes in left ventricular end-diastolic volume during space flight and tilt may be similar, but follow a different time course. Nevertheless, head-down tilt at 5 degrees for 6 hours mimics some (stroke volume, systolic and diastolic blood pressure, mean arterial blood pressure, and total resistance), but not all, of the changes occurring in an equivalent time of space flight. The magnitude of the change in the mean heart rate response to standing was greater after six hours of tilt at -5 degrees or 10 degrees. Thus, results from the stand test after 6 hours of bed rest at -5 degrees and 10 degrees, but not at 20 degrees or 42 degrees, are similar to those obtained after space flight.

North Polar Water Ice by Weight

NASA Technical Reports Server (NTRS)

2003-01-01

December 8, 2003

This map shows the percent of water by weight in near-surface materials of Mars' north polar region. It is derived from the gamma ray spectrometer component of the gamma ray spectrometer suite of instruments on NASA's Mars Odyssey spacecraft.

Significant concentrations of water (greater than 20 percent) are poleward of 55 degrees north latitude. The highest concentration, greater than 50 percent, is between 75 degrees north and the pole. Another area with a high concentration of water by weight is in the north polar plains between longitudes minus 105 degrees and minus 140 degrees, and between latitudes 60 degrees and 75 degrees.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for the NASA Office of Space Science in Washington. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Space Systems, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL.

[Hygienic problems of residential and public buildings].

PubMed

Chubirko, M I; Pichuzhkina, N M; Masaĭlova, L A; Kharchenko, I A

2007-01-01

A questionnaire survey made in different Voronezh population groups suggests that they spend 80 to 90% of time in the enclosed space. The greatest contribution to the chemical load caused by ambient air pollution made by production areas (54.9%) in the adult able-bodied population and by dwelling areas (56.0-86.9%) in children, adolescents, and pensioners. Pollution of ambient air (K = 9.19) is pronounced to a lesser degree than that of the air of office buildings (K = 12.49), which suggests that there are internal contamination sources in the closed space. The results of the questionnaire survey of respondents suggest that 20% suffer from allergic diseases and 7% of them associate these diseases with dwelling area contamination.

Earth observation of Manam Island taken from Columbia during STS-93

NASA Image and Video Library

1999-07-25

STS093-709-051 (23-27 July 1999) --- The STS-93 astronauts aboard the Space Shuttle Columbia took this picture of the volcanic island of Manam, along the northeast coast of Papua New Guinea. Manam is one in a string of currently active volcanoes called the Bismarck Arc. It is the most active of the group, having begun its present activity in 1994. The plume of steam and ash streaming from its crater extends more than 20 miles into the atmosphere. When the photo was taken, the shuttle was flying over a point located at 12.2 degrees south latitude and 132.0 degrees east longitude. Data back information on the 70mm film lists time and date of the photo as 05:42:31 GMT, July 25, 1999 (orbit 33).

Influence of space size of abutment screw access channel on the amount of extruded excess cement and marginal accuracy of cement-retained single implant restorations.

PubMed

Al Amri, Mohammad D; Al-Johany, Sulieman S; Al-Qarni, Mohammed N; Al-Bakri, Ahmed S; Al-Maflehi, Nassr S; Abualsaud, Haythem S

2018-02-01

The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-μm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (P<.001). The mean marginal discrepancy (μm) of the pre-cemented group (29.5 ±8.2) was significantly different (P<.01) from that of the NS (72.3 ±13.7), the 1MMS (70.1 ±19), and the 2MMS group (70.1 ±18.8). No significant differences were found in marginal accuracy among the 3 test groups (P=.942). Within the limitations of this in vitro study, leaving a 2-mm space in the SAC reduced the amount of extruded excess cement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Investigation of low energy space plasma

NASA Technical Reports Server (NTRS)

Comfort, R. H.; Horwitz, J. L.

1986-01-01

A statistical study of 1982 data for occurrences of equatorially trapped plasma has been extended. The previous survey, which utilized only the MSFC summary fiche, has been supplemented with the GSFC summary fiche, which has had the effect of substantially improving the late 1982 coverage. It was found that in the post midnight region (1 - 3 LT), the trapped plasma is limited to + or - 5 degrees magnetic latitude, while in the early afternoon (13-15 LT), latitude ranges as high as + or 30 degrees are found. This survey has provided a link to earlier ATS-6 and ISEE studies of pancake distributions. Although the most energetic, and most anisotopic plasmas are trapped within a few degrees of the equator, the results of these equatorial interactions extend substantially along the magnetic field line in the afternoon and dusk region and these high latitude extensions were previously studied by the Huntsville group. Results of this study were incorporated into a revision of the equatorial ion paper, which has been resubmitted and accepted for publication.

Dead space and slope indices from the expiratory carbon dioxide tension-volume curve.

PubMed

Kars, A H; Bogaard, J M; Stijnen, T; de Vries, J; Verbraak, A F; Hilvering, C

1997-08-01

The slope of phase 3 and three noninvasively determined dead space estimates derived from the expiratory carbon dioxide tension (PCO2) versus volume curve, including the Bohr dead space (VD,Bohr), the Fowler dead space (VD,Fowler) and pre-interface expirate (PIE), were investigated in 28 healthy control subjects, 12 asthma and 29 emphysema patients (20 severely obstructed and nine moderately obstructed) with the aim to establish diagnostic value. Because breath volume and frequency are closely related to CO2 elimination, the recording procedures included varying breath volumes in all subjects during self-chosen/natural breathing frequency, and fixed frequencies of 10, 15 and 20 breaths x min(-1) with varying breath volumes only in the healthy controls. From the relationships of the variables with tidal volume (VT), the values at 1 L were estimated to compare the groups. The slopes of phase 3 and VD,Bohr at 1 L VT showed the most significant difference between controls and patients with asthma or emphysema, compared to the other two dead space estimates, and were related to the degree of airways obstruction. Discrimination between no-emphysema (asthma and controls) and emphysema patients was possible on the basis of a plot of intercept and slope of the relationship between VD,Bohr and VT. A combination of both the slope of phase 3 and VD,Bohr of a breath of 1 L was equally discriminating. The influence of fixed frequencies in the controls did not change the results. The conclusion is that Bohr dead space in relation to tidal volume seems to have diagnostic properties separating patients with asthma from patients with emphysema with the same degree of airways obstruction. Equally discriminating was a combination of both phase 3 and Bohr dead space of a breath of 1 L. The different pathophysiological mechanisms in asthma and emphysema leading to airways obstruction are probably responsible for these results.

Kennedy Space Center (KSC) Pad B Catenary Capability Analysis and Technical Exchange Meeting (TEM) Support

NASA Technical Reports Server (NTRS)

Wilson, Timmy R.; Kichak, Robert; Rakov, Vladimir; Kithil, Richard, Jr.; Sargent, Noel B.

2009-01-01

The existing lightning protection system at Pad 39B for the Space Shuttle is an outgrowth of a system that was put in place for the Apollo Program. Dr. Frank Fisher of Lightning Technologies was a key participant in the design and implementation of that system. He conveyed to the NESC team that the catenary wire provision was put in place quickly (as assurance against possible vehicle damage causing critical launch delays) rather than being implemented as a comprehensive system designed to provide a high degree of guaranteed protection. Also, the technology of lightning protection has evolved over time with considerable work being conducted by groups such as the electric utilities companies, aircraft manufacturers, universities, and others. Several accepted present-day methods for analysis of lightning protection were used by Drs. Medelius and Mata to study the expected lightning environment for the Pad 39B facility and to analyze the degree of protection against direct lightning attachment to the Space Shuttle. The specific physical configuration directly affects the vulnerability, so cases that were considered included the RSS next to and rolled back from the Space Shuttle, and the GOx Vent Arm both extended and withdrawn from the ET. Elements of the lightning protection system at Pad 39B are shown in Figure 6.0-1 and consist of an 80 foot insulating mast on top of the Fixed Support Structure (FSS), a catenary wire system that runs from the mast in a North/South direction to grounds 1000 feet away on each side of the mast, the RSS which can either be next to or away from the Space Shuttle, and a GOx vent that can either be extended or retracted from the top of the ET.

Effective Chern-Simons actions of particles coupled to 3D gravity

NASA Astrophysics Data System (ADS)

Trześniewski, Tomasz

2018-03-01

Point particles in 3D gravity are known to behave as topological defects, while gravitational field can be expressed as the Chern-Simons theory of the appropriate local isometry group of spacetime. In the case of the Poincaré group, integrating out the gravitational degrees of freedom it is possible to obtain the effective action for particle dynamics. We review the known results, both for single and multiple particles, and attempt to extend this approach to the (anti-)de Sitter group, using the factorizations of isometry groups into the double product of the Lorentz group and AN (2) group. On the other hand, for the de Sitter group one can also perform a contraction to the semidirect product of AN (2) and the translation group. The corresponding effective action curiously describes a Carrollian particle with the AN (2) momentum space. We derive this contraction in a more rigorous manner and further explore its properties, including a generalization to the multiparticle case.

Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2}: A new bismuth oxo-selenite bromide

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

Berdonosov, Peter S., E-mail: berdonosov@inorg.chem.msu.ru; Olenev, Andrei V.; Kirsanova, Maria A.

2012-12-15

A new bismuth oxo-selenite bromide Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} was synthesized and structurally characterized. The crystal structure belongs to the triclinic system (space group P1-bar , Z=2, a=7.1253(7) A, b=10.972(1) A, c=12.117(1) A, {alpha}=67.765(7) Degree-Sign , {beta}=82.188(8) Degree-Sign , {gamma}=78.445(7) Degree-Sign ) and is unrelated to those of other known oxo-selenite halides. It can be considered as an open framework composed of BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons forming channels running along [1 0 0] direction which contain the selenium atoms in pyramidal shape oxygen coordination (SeO{sub 3}E). The spectroscopic properties and thermal stability were studied. Themore » new compound is stable up to 400 Degree-Sign C. - graphical abstract: New bismuth oxo-selenite bromide with new open framework structure. Highlights: Black-Right-Pointing-Pointer New bismuth oxo-selenite bromide was found and structurally characterized. Black-Right-Pointing-Pointer Bi{sub 6}(SeO{sub 3}){sub 3}O{sub 5}Br{sub 2} exhibit a new open framework structure type. Black-Right-Pointing-Pointer BiO{sub x} or BiO{sub y}Br{sub z} polyhedrons form channels in the structure which are decorated by [SeO{sub 3}E] groups.« less

Structural study of polymorphism in methylprednisolone aceponate

NASA Astrophysics Data System (ADS)

Knyazev, A. V.; Somov, N. V.; Shipilova, A. S.; Gusarova, E. V.; Knyazeva, S. S.; Stepanova, O. V.; Chuprunov, E. V.

2017-08-01

The crystal structures of methylprednisolone aceponate were determined by X-ray diffraction analysis at temperatures 90 K and 150 K: space group P212121, a = 14.8592(2), b = 19.6844(5), c = 26.1626(4) Å, Z = 12; R = 0.0598 (T = 90 K); space group P212121, a = 6.57348(14), b = 14.8295(3), c = 26.2214(5) Å, Z = 4; R = 0.0518 (T = 150 K). Features of structural changes in the phase transition were revealed. The abrupt change in the unit cell parameters in the phase transition was shown by low-temperature X-ray powder. The methods of degree of invariance of crystal electron density and molecular Voronoi-Dirichlet polyhedra were used for the analysis of polymorphism in methylprednisolone aceponate. The atomic structure at 90 K have a translational pseudosymmetry of electron density η = 0.329(1). The decrease of number of intermolecular contacts in the high-temperature modification due to rupture of intermolecular non-valence contacts C/O was observed.

Expression, crystallization and preliminary crystallographic analysis of the extracellular IgV-like domain of the human natural killer cell inhibitory receptor p75/AIRM1.

PubMed

Dimasi, Nazzareno; Moretta, Lorenzo; Biassoni, Roberto; Mariuzza, Roy A

2003-10-01

p75/AIRM1 (Siglec-7) is a sialic acid-binding Ig-like lectin recently identified as an inhibitory receptor on natural killer cells. The expression, in vitro folding, circular-dichroism spectroscopy, crystallization and preliminary X-ray characterization of the Ig-V like domain of p75/AIRM1 are reported. X-ray data were collected from a single crystal at 100 K, with a maximum useful diffraction pattern extending to 1.45 A resolution on a synchrotron source. The crystal belongs to a primitive monoclinic space group, with unit-cell parameters a = 32.65, b = 49.72, c = 39.79 A, alpha = gamma = 90, beta = 113 degrees. The systematic absences indicate that the space group is P2(1). Assuming one molecule per asymmetric unit, V(M) (the Matthews coefficient) was calculated to be 1.879 A(3) Da(-1) and the solvent content was estimated to be 32.01%.

Dodecahedral space topology as an explanation for weak wide-angle temperature correlations in the cosmic microwave background.

PubMed

Luminet, Jean-Pierre; Weeks, Jeffrey R; Riazuelo, Alain; Lehoucq, Roland; Uzan, Jean-Philippe

2003-10-09

The current 'standard model' of cosmology posits an infinite flat universe forever expanding under the pressure of dark energy. First-year data from the Wilkinson Microwave Anisotropy Probe (WMAP) confirm this model to spectacular precision on all but the largest scales. Temperature correlations across the microwave sky match expectations on angular scales narrower than 60 degrees but, contrary to predictions, vanish on scales wider than 60 degrees. Several explanations have been proposed. One natural approach questions the underlying geometry of space--namely, its curvature and topology. In an infinite flat space, waves from the Big Bang would fill the universe on all length scales. The observed lack of temperature correlations on scales beyond 60 degrees means that the broadest waves are missing, perhaps because space itself is not big enough to support them. Here we present a simple geometrical model of a finite space--the Poincaré dodecahedral space--which accounts for WMAP's observations with no fine-tuning required. The predicted density is Omega(0) approximately 1.013 > 1, and the model also predicts temperature correlations in matching circles on the sky.

Assessment of the perception of verticality and horizontality with self-paced saccades.

PubMed

Pettorossi, V E; Bambagioni, D; Bronstein, A M; Gresty, M A

1998-07-01

We investigated the ability of human subjects (Ss) to make self-paced saccades in the earth-vertical and horizontal directions (space-referenced task) and in the direction of the head-vertical and horizontal axis (self-referenced task) during whole body tilts of 0 degrees, 22.5 degrees, 45 degrees and 90 degrees in the frontal (roll) plane. Saccades were recorded in the dark with computerised video-oculography. During space-referenced tasks, the saccade vectors did not fully counter-rotate to compensate for larger angles of body tilt. This finding is in agreement with the 'A' effect reported for the visual vertical. The error was significantly larger for saccades intended to be space-horizontal than space-vertical. This vertico-horizontal dissociation implies greater difficulty in defining horizontality than verticality with the non-visual motor task employed. In contrast, normal Ss (and an alabyrinthine subject tested) were accurate in orienting saccades to their own (cranio-centric) vertical and horizontal axes regardless of tilt indicating that cranio-centric perception is robust and apparently not affected by gravitational influences.

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility inspect the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on its handling fixture. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

NASA Image and Video Library

1997-01-18

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility inspect the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on its handling fixture. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility lift the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) prior to its installation in the Second Axial Carrier. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

NASA Image and Video Library

1997-01-18

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility lift the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) prior to its installation in the Second Axial Carrier. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility lower the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) into the Second Axial Carrier. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

NASA Image and Video Library

1997-01-18

KENNEDY SPACE CENTER, FLA. - Workers in KSC's Vertical Processing Facility lower the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) into the Second Axial Carrier. NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument — its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is targeted Feb. 11 aboard Discovery with a crew of seven.

The use of multidimensional scaling for facilities layout - An application to the design of the Space Station

NASA Technical Reports Server (NTRS)

Tullis, Thomas S.; Bied Sperling, Barbra; Steinberg, A. L.

1986-01-01

Before an optimum layout of the facilities for the proposed Space Station can be designed, it is necessary to understand the functions that will be performed by the Space Station crew and the relationships among those functions. Five criteria for assessing functional relationships were identified. For each of these criteria, a matrix representing the degree of association of all pairs of functions was developed. The key to making inferences about the layout of the Space Station from these matrices was the use of multidimensional scaling (MDS). Applying MDS to these matrices resulted in spatial configurations of the crew functions in which smaller distances in the MDS configuration reflected closer associations. An MDS analysis of a composite matrix formed by combining the five individual matrices resulted in two dimensions that describe the configuration: a 'private-public' dimension and a 'group-individual' dimension. Seven specific recommendations for Space Station layout were derived from analyses of the MDS configurations. Although these techniques have been applied to the design of the Space Station, they can be applied to the design of any facility where people live or work.

Modulation of vergence by off-vertical yaw axis rotation in the monkey: normal characteristics and effects of space flight

NASA Technical Reports Server (NTRS)

Dai, M.; Raphan, T.; Kozlovskaya, I.; Cohen, B.

1996-01-01

Horizontal movements of both eyes were recorded simultaneously using scleral search coils in 2 rhesus monkeys before and after the COSMOS 2229 space-flight of 1992-1993. Another 9 monkeys were tested at comparable time intervals and served as controls. Ocular vergence, defined as the difference in horizontal position between the left and right eyes, was measured during off-vertical yaw axis rotation (OVAR) in darkness. Vergence was modulated sinusoidally as a function of head position with regard to gravity during OVAR. The amplitude of peak-to-peak modulation increased with increments in tilt of the angle of the rotational axis (OVAR tilt angle) that ranged from 15 degrees to 90 degrees. Of the 11 monkeys tested, 1 had no measurable modulation in vergence. In the other 10, the mean amplitude of the peak to peak modulation was 5.5 degrees +/- 1.3 degrees at 90 degrees tilt. Each of these monkeys had maximal vergence when its nose was pointed close to upward (gravity back; mean phase: -0.9 degree +/- 26 degrees). After space flight, the modulation in vergence was reduced by over 50% for the two flight monkeys, but the phase of vergence modulation was not altered. The reduction in vergence modulation was sustained for the 11-day postflight testing period. We conclude that changes in vergence are induced in monkeys by the sinusoidal component of gravity acting along the naso-occipital axis during yaw axis OVAR, and that the modulation of the vergence reflex is significantly less sensitive to linear acceleration after space flight.

NASA's James Webb Space Telescope Science Instruments Begin Final Super Cold Test at Goddard

NASA Image and Video Library

2017-12-08

At NASA's James Webb Space Telescope's final destination in space, one million miles away from Earth, it will operate at incredibly cold temperatures of -387 degrees Fahrenheit, or 40 degrees Kelvin. This is 260 degrees Fahrenheit colder than any place on the Earth’s surface has ever been. So first, this final super cold test at Goddard will prepare the Integrated Science Instrument Module (ISIM), or the “heart” of the telescope, for space. Read more: go.nasa.gov/1KFPwJG Contamination Control Engineer Alan Abeel conducts final inspections and places contamination foils before the start of the test. Credit: NASA/Goddard/Chris Gunn NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Degree Partnerships in the BC Context. Special Report, December 2006

ERIC Educational Resources Information Center

Gaber, Devron

2006-01-01

Degree partnership is a term used to describe a variety of models that provide a guarantee to students who maintain adequate grades in a college program of continuation of degree studies at another institution. This "guarantee" that space will be available for degree completion at another institution separates degree partnerships from…

Scaling properties of the two-dimensional randomly stirred Navier-Stokes equation.

PubMed

Mazzino, Andrea; Muratore-Ginanneschi, Paolo; Musacchio, Stefano

2007-10-05

We inquire into the scaling properties of the 2D Navier-Stokes equation sustained by a force field with Gaussian statistics, white noise in time, and with a power-law correlation in momentum space of degree 2 - 2 epsilon. This is at variance with the setting usually assumed to derive Kraichnan's classical theory. We contrast accurate numerical experiments with the different predictions provided for the small epsilon regime by Kraichnan's double cascade theory and by renormalization group analysis. We give clear evidence that for all epsilon, Kraichnan's theory is consistent with the observed phenomenology. Our results call for a revision in the renormalization group analysis of (2D) fully developed turbulence.

Crystal Structure and Magnetic Behavior of Two New Dinuclear Carbonato-Bridged Copper(II) Compounds. Superexchange Pathway for the Different Coordination Modes of the Carbonato Bridge in Polynuclear Copper(II) Compounds.

PubMed

Escuer, Albert; Mautner, Franz A.; Peñalba, Evaristo; Vicente, Ramon

1998-08-24

Four new &mgr;-CO(3)(2-) copper(II) complexes with different coordination modes for the carbonato bridge have been obtained by fixation of atmospheric CO(2): {(&mgr;(3)-CO(3))[Cu(3)(ClO(4))(3)(Et(3)dien)(3)]}(ClO(4)) (1), Et(3)dien = N,N',N"-triethylbis(2-aminoethane)amine; {(&mgr;-CO(3))[Cu(2)(H(2)O)(Et(4)dien)(2)]}(ClO(4))(2).H(2)O (2), Et(4)dien = N,N,N",N"-tetraethyl-bis(2-aminoethane)amine; {(&mgr;-CO(3))[Cu(2)(H(2)O)(2)(EtMe(4)dien)(2)]} (ClO(4))(2).2H(2)O (3), EtMe(4)dien = N'-ethyl-N,N,N",N"-tetramethylbis(2-aminoethane)amine; and {(&mgr;-CO(3))[Cu(2)(H(2)O)(Me(5)dien)(2)]}(ClO(4))(2).H(2)O (4), Me(5)dien = N,N,N',N",N"-pentamethylbis(2-aminoethane)amine. The crystal structures have been solved for 2, monoclinic system, space group P2(1)/n, formula [C(25)H(62)Cl(2)Cu(2)N(6)O(13)] with a = 12.763(6) Å, b = 25.125(8) Å, c = 13.261(4) Å, beta = 111.85(3) degrees, Z = 4, and for 3, triclinic system, space group P&onemacr;, formula [C(21)H(58)Cl(2)Cu(2)N(6)O(15)] with a = 8.412(3) Å, b = 14.667(4) Å, c = 16.555(5) Å, alpha = 99.66(2) degrees, beta = 102.14(2) degrees, gamma = 104.72(2) degrees, Z = 2. Susceptibility measurements show ferromagnetic behavior (J = +6.7(6) cm(-)(1)) for the trinuclear compound 1 whereas 2-4 are antiferromagnetically coupled with J = -17.8(8), -125.5(9), and -21.2(3) cm(-)(1) respectively. Certain synthetic aspects that may be related to the nuclearity of the copper(II) &mgr;-CO(3)(2-) compounds and the superexchange pathway for the different coordination modes of the carbonato bridge are discussed.

Aqueous V(V)-peroxo-amino acid chemistry. Synthesis, structural and spectroscopic characterization of unusual ternary dinuclear tetraperoxo vanadium(V)-glycine complexes.

PubMed

Gabriel, C; Kaliva, M; Venetis, J; Baran, P; Rodriguez-Escudero, I; Voyiatzis, G; Zervou, M; Salifoglou, A

2009-01-19

Vanadium participation in cellular events entails in-depth comprehension of its soluble and bioavailable forms bearing physiological ligands in aqueous distributions of binary and ternary systems. Poised to understand the ternary V(V)-H(2)O(2)-amino acid interactions relevant to that metal ion's biological role, we have launched synthetic efforts involving the physiological ligands glycine and H(2)O(2). In a pH-specific fashion, V(2)O(5), glycine, and H(2)O(2) reacted and afforded the unusual complexes (H(3)O)(2)[V(2)(O)(2)(mu(2):eta(2):eta(1)-O(2))(2)(eta(2)-O(2))(2)(C(2)H(5)NO(2))] x 5/4 H(2)O (1) and K(2)[V(2)(O)(2)(mu(2):eta(2):eta(1)-O(2))(2)(eta(2)-O(2))(2)(C(2)H(5)NO(2))] x H(2)O (2). 1 crystallizes in the triclinic space group P1, with a = 7.805(4) A, b = 8.134(5) A, c = 12.010(7) A, alpha = 72.298(9) degrees, beta = 72.991(9) degrees, gamma = 64.111(9) degrees, V = 641.9(6) A(3), and Z = 2. 2 crystallizes in the triclinic space group P1, with a = 7.6766(9) A, b = 7.9534(9) A, c = 11.7494(13) A, alpha = 71.768(2) degrees, beta = 73.233(2) degrees, gamma = 65.660(2) degrees, V = 610.15(12) A(3), and Z = 2. Both complexes 1 and 2 were characterized by UV/visible, LC-MS, FT-IR, Raman, NMR spectroscopy, cyclic voltammetry, and X-ray crystallography. The structures of 1 and 2 reveal the presence of unusual ternary dinuclear vanadium-tetraperoxo-glycine complexes containing [(V(V)=O)(O(2))(2)](-) units interacting through long V-O bonds and an effective glycinate bridge. The latter ligand is present in the dianionic assembly as a bidentate moiety spanning both V(V) centers in a zwitterionic form. The collective physicochemical properties of the two ternary species 1 and 2 project the chemical role of the low molecular mass biosubstrate glycine in binding V(V)-diperoxo units, thereby stabilizing a dinuclear V(V)-tetraperoxo dianion. Structural comparisons of the anions in 1 and 2 with other known dinuclear V(V)-tetraperoxo binary anionic species provide insight into the chemical reactivity of V(V)-diperoxo species in key cellular events such as insulin mimesis and antitumorigenicity, potentially modulated by the presence of glycinate and hydrogen peroxide.

Synthesis, crystal structure and magnetic characterization of metal(II) coordination polymers based on 2-carboxyethylphosphonic acid and 1,10-phenanthroline (metal=Cu, Co, Cd)

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

Fernandez-Zapico, Eva; Montejo-Bernardo, Jose Manuel; D'Vries, Richard

2011-12-15

Three non-isostructural metal(II) coordination polymers (metal=copper, cobalt, cadmium) were synthesized under the same mild hydrothermal conditions (T=408 K) by mixture of the corresponding metal acetate with 2-carboxyethylphosphonic acid and 1,10-phenanthroline (1:1:1 M ratio) and their structures were determined by single-crystal X-ray diffraction. Cu{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2}(H{sub 2}O){sub 2} and Cd{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2} are triclinic (space group P-1) with a=7.908(5) A, b=10.373(5) A, c=11.515(5) A, {alpha}=111.683(5) Degree-Sign , {beta}=95.801(5) Degree-Sign , {gamma}=110.212(5) Degree-Sign (T=120 K), and a=8.162(5) A, b=9.500(5) A, c=11.148(5) A, {alpha}=102.623(5) Degree-Sign , {beta}=98.607(5) Degree-Sign ,more » {gamma}=113.004(5) Degree-Sign (T=293 K), respectively. In contrast, [Co{sub 2}(HO{sub 3}PCH{sub 2}CH{sub 2}COO){sub 2}(C{sub 12}H{sub 8}N{sub 2}){sub 2}({mu}-OH{sub 2})](H{sub 2}O) is orthorhombic (space group Pbcn) with a=21.1057(2) A, b=9.8231(1) A, c=15.4251(1) A (T=120 K). For these three compounds, structural features, including H-bond network and the {pi}-{pi} stacking interactions, and thermal stability are reported and discussed. None of the materials present a long-range magnetic order in the range of temperatures investigated from 300 K down to 1.8 K. - Graphical abstract: In same synthetic conditions, both the chemical and structural features of three transition metal(II) coordination polymers based on 2-carboxyethylphosphonate and 1-10 Prime -phenanthroline are influenced by the metal cation characteristics, leading to non-homologous materials with different properties, which show the high chemical versatility of this interesting system. Highlights: Black-Right-Pointing-Pointer Non-isostructural metal coordination polymers were synthesized under mild hydrothermal conditions. Black-Right-Pointing-Pointer Ligand's flexibility provides the opportunity to design compounds with tailored properties. Black-Right-Pointing-Pointer Structural changes in the secondary building units are induced by metal features.« less

Relative commutativity degree of some dihedral groups

NASA Astrophysics Data System (ADS)

Abdul Hamid, Muhanizah; Mohd Ali, Nor Muhainiah; Sarmin, Nor Haniza; Abd Manaf, Fadila Normahia

2013-04-01

The commutativity degree of a finite group G was introduced by Erdos and Turan for symmetric groups, finite groups and finite rings in 1968. The commutativity degree, P(G), is defined as the probability that a random pair of elements in a group commute. The relative commutativity degree of a group G is defined as the probability for an element of subgroup, H and an element of G to commute with one another and denoted by P(H,G). In this research the relative commutativity degree of some dihedral groups are determined.

[Application of distal palm perforator mini-flap in repair of scar contracture of digital web-spaces].

PubMed

Zhou, Xiao; Xu, Yajun; Rui, Yongjun; Shou, Kuishui; Yao, Qun

2011-02-01

To discuss the effectiveness of distal palm perforator mini-flap in the treatment of scar contracture of digital web-spaces. Between August 2008 and March 2010, 6 cases of scar contracture of digital web-spaces were treated, including 4 males and 2 females and aging 16-68 years (mean, 45 years). The causes were burn injury, twisting injury, and crush injury in 2 cases, respectively. The disease duration was from 3 months to 3 years. The affected digital web-spaces were from index finger to middle finger in 2 cases, from middle finger to ring finger in 3 cases, and from ring finger to small finger in 1 case. The maximum abduction degree of digital web-spaces was 5-10 degrees. The sizes and the depths of reshape of digital web-spaces disappeared. The defect size ranged from 20 mm x 8 mm to 30 mm x 13 mm after opening digital web-spaces. The size of the distal palm perforator mini-flap ranged from 25 mm x 10 mm to 35 mm x 15 mm. The donor sites were sutured directly. All 6 flaps survived and got primary healing. Incisions at donor sites healed by first intention. All patients were followed up 6-12 months. The reconstructed digital web-spaces had good appearance and soft texture. The range of motion of metacarpophalangeal joint was normal. The sizes and the depths of reshape of digital web-spaces were similar to normal ones. The maximum abduction degree of digital web-spaces was 40-60 degrees. There was no scar contracture of incision of palm. The shape of flaps and function of the fingers were satisfactory after 6-12 months of follow-up. It is an ideal method to treat scar contracture of digital web-spaces with distal palm perforator mini-flap.

Influence of the activation temperature on the SO2 removal capacity and mechanical performance of pelletized activated chars.

PubMed

Rubio, B; Izquierdo, M T; Mayoral, M C; Andrés, J M

2001-09-01

The influence of steam activation temperature on the SO2 removal capability of subbituminous coal char pellets (SCCP) as well as the changes in their mechanical properties, were studied. The SCCP were prepared by pressing at 125 MPa a blend of a char, obtained by carbonization at 850 degrees C, and a commercial coal tar pitch. After a curing stage in air at 200 degrees C and a heat treatment at 900 degrees C in nitrogen, the SCCP were activated with steam (10g H2O min(-1)) for two hours at several temperatures: 600, 700, 750 and 800 degrees C. The SO2 adsorption capacity tests carried out at simulated flue gas conditions (100 degrees C, 10% H2O, 6% O2, 1s space velocity) show an important increase in the amount of adsorbed SO2 of the activated SCCP with respect to parent ones, whereas their mechanical performance decreases in the same proportion, mainly in the interval 700-750 degrees C. Increasing the temperature of activation, the SCCP undergo significant changes in textural features (total surface area measured in N2 and CO2, pore volume) as well as in surface oxygenated groups, as shown by TPD experiments. There is an optimum ratio between both parameters (around 8 micromol g(-1)) for the SO2 conversion at the studied conditions.

Factors associated with postoperative C5 palsy after expansive open-door laminoplasty: retrospective cohort study using multivariable analysis.

PubMed

Tsuji, Takashi; Matsumoto, Morio; Nakamura, Masaya; Ishii, Ken; Fujita, Nobuyuki; Chiba, Kazuhiro; Watanabe, Kota

2017-09-01

The aim of the present study was to investigate the factors associated with C5 palsy by focusing on radiological parameters using multivariable analysis. The authors retrospectively assessed 190 patients with cervical spondylotic myelopathy treated by open-door laminoplasty. Four radiographic parameters-the number of expanded lamina, C3-C7 angle, lamina open angle and space anterior to the spinal cord-were evaluated to clarify the factors associated with C5 palsy. Of the 190 patients, 11 developed C5 palsy, giving an overall incidence of 5.8%. Although the number of expanded lamina, lamina open angle and space anterior to the spinal cord were significantly larger in C5 palsy group than those in non-palsy group, a multiple logistic regression analysis revealed that only the space anterior to the spinal cord (odds ratio 2.60) was a significant independent factor associated with C5 palsy. A multiple linear regression analysis indicated that the lamina open angle was associated with the space anterior to the spinal cord and the analysis identified the following equation: space anterior to the spinal cord (mm) = 1.54 + 0.09 × lamina open angle (degree). A cut-off value of 53.5° for the lamina open angle predicted the development of C5 palsy with a sensitivity of 72.7% and a specificity of 83.2%. The larger postoperative space anterior to the spinal cord, which was associated with the lamina open angle, was positively correlated with the higher incidence of C5 palsy.

[Clinical significance of Q-angle under different conditions in recurrent patellar dislocation].

PubMed

Wang, Zhijie; Chen, You; Li, Anping; Long, Yi

2014-01-01

To investigate the clinical significance of Q-angle measuring under different conditions in female recurrent patellar dislocation female patients. Between August 2012 and March 2013, 10 female patients (11 knees) with recurrent patellar dislocation were collected as trial group; 20 female patients (20 knees) with simple meniscus injury were collected as control group at the same time. Q-angle was measured in extension, 30 degrees flexion, 30 degrees flexion with manual correction, and surgical correction in the trial group, and only in extension and 30 degrees flexion in the control group. Then the difference value of Q-angle between extension and 30 degrees flexion (Q-angle in extension subtracts Q-angle in 30 flexion) were calculated. Independent sample t-test was used to analyze Q-angle degrees in extension, 30 degrees flexion, and the changed degrees of 2 groups. The Q-angle between manual correction and surgical correction of the trial group was analyzed by paired t-test. The Q-angle in extension, Q-angle in 30 degrees flexion, and difference value of Q-angle between extension and 30 degrees flexion were (17.2 +/- 3.6), (14.3 +/- 3.0), and (2.9 +/- 1.9) degrees in the trial group and were (15.2 +/- 3.4), (14.4 +/- 3.5), and (0.8 +/- 1.7) degrees in the control group. No significant difference was found in Q-angle of extension or Q-angle of 30 degrees flexion between 2 groups (P > 0.05), but the difference value of Q-angle between extension and 30 degrees flexion in the trial group was significantly larger than that in the control group (t = 3.253, P = 0.003). The Q-angle in 30 degrees flexion with manual correction and surgical correction in the trial group was (19.8 +/- 3.4) degrees and (18.9 +/- 3.8) degrees respectively, showing no significant difference (t = 2.193, P = 0.053). When a female patient's Q-angle in 30 degrees flexion knee changes obviously compared with Q-angle in extension position, recurrent patellar dislocation should be considered. For female patients with recurrent patellar dislocation, the preoperative Q-angle in 30 degrees flexion with manual correction should be measured, which can help increasing the accuracy of evaluation whether rearrangement should be performed.

Results of tests of advanced flexible insulation vortex and flow environments in the North American Aerodynamics Laboratory lowspeed wind tunnel using 0.0405-scale Space Shuttle Orbiter model 16-0 (test OA-309)

NASA Technical Reports Server (NTRS)

Marshall, B. A.; Nichols, M. E.

1984-01-01

An experimental investigation (Test OA-309) was conducted using 0.0405-scale Space Shuttle Orbiter Model 16-0 in the North American Aerodynamics Laboratory 7.75 x 11.00-foot Lowspeed Wind Tunnel. The primary purpose was to locate and study any flow conditions or vortices that might have caused damage to the Advanced Flexible Reusable Surface Insulation (AFRSI) during the Space Transportation System STS-6 mission. A secondary objective was to evaluate vortex generators to be used for Wind Tunnel Test OS-314. Flowfield visualization was obtained by means of smoke, tufts, and oil flow. The test was conducted at Mach numbers between 0.07 and 0.23 and at dynamic pressures between 7 and 35 pounds per square foot. The angle-of-attack range of the model was -5 degrees through 35 degrees at 0 or 2 degrees of sideslip, while roll angle was held constant at zero degrees. The vortex generators were studied at angles of 0, 5, 10, and 15 degrees.

Probing coherence in microcavity frequency combs via optical pulse shaping

NASA Astrophysics Data System (ADS)

Ferdous, Fahmida; Miao, Houxun; Wang, Pei-Hsun; Leaird, Daniel E.; Srinivasan, Kartik; Chen, Lei; Aksyuk, Vladimir; Weiner, Andrew M.

2012-09-01

Recent investigations of microcavity frequency combs based on cascaded four-wave mixing have revealed a link between the evolution of the optical spectrum and the observed temporal coherence. Here we study a silicon nitride microresonator for which the initial four-wave mixing sidebands are spaced by multiple free spectral ranges (FSRs) from the pump, then fill in to yield a comb with single FSR spacing, resulting in partial coherence. By using a pulse shaper to select and manipulate the phase of various subsets of spectral lines, we are able to probe the structure of the coherence within the partially coherent comb. Our data demonstrate strong variation in the degree of mutual coherence between different groups of lines and provide support for a simple model of partially coherent comb formation.

Hands-On Educational Programs and Projects at SICSA

NASA Astrophysics Data System (ADS)

Bell, L.

2002-01-01

The Sasakawa International Center for Space Architecture (SICSA) has a long history of projects that involve the design of space structures, including habitats for low-Earth orbit (LEO) and planetary applications. Some of these projects are supported by corporate sponsors, such as a space tourism research, planning and design study conducted for the owner of national U.S. hotel chain. Some have been undertaken in support of programs sponsored by the State Government of Texas, including current commercial spaceport development planning for the Texas Aerospace Commission and three counties that represent candidate spaceport sites. Other projects have been supported by NASA and the Texas Aerospace Consortium, including the design and development of SICSA's "Space Habitation Laboratory", a space station module sized environmental simulator facility which has been featured in the "NASA Select" television broadcast series. This presentation will highlight representative projects. SICSA is internationally recognized for its leadership in the field of space architecture. Many program graduates have embarked upon productive and rewarding careers with aerospace organizations throughout the world. NASA has awarded certificates of appreciation to SICSA for significant achievements contributing to its advanced design initiatives. SICSA and its work have been featured in numerous popular magazines, professional publications, and public media broadcasts in many countries. SICSA applies a very comprehensive scope of activities to the practice of space architecture. Important roles include mission planning conceptualization of orbital and planetary structures and assembly processes, and design of habitats to optimize human safety, adaptation and productivity. SICSA sponsors educational programs for upper division undergraduate students and graduate students with interests in space and experimental architecture. Many fourth year participants continue in the SICSA program throughout their remaining undergraduate studies, and are joined by other new fifth year students. Selected graduate applicants holding a professional degree in architecture from accredited colleges and universities can earn a Master of Architecture degree with a specialization in space and experimental architecture upon completion of 32 credit hours of study which includes two six-hour design studios. Accepted graduate students seeking a Master of Architecture degree who do not hold a professional architecture degree may enter SICSA studios during the final year of their minimum 72 credit hours of study. Subject to necessary University of Houston and Texas Higher Education Coordinating Board approvals, SICSA and the College of Architecture propose to expand their graduate education role to add a Master of Science in Space Architecture degree program. This new program is primarily being planned in response to known interests of non-architect professionals from NASA and aerospace corporations who wish to pursue advanced space architecture research and design studies. The program will be also available to working professionals holding an undergraduate architectural degree.

Vacuum Strength of Two Candidate Glasses for a Space Observatory

NASA Technical Reports Server (NTRS)

Manning, Timothy Andrew; Tucker, Dennis S.; Herren, Kenneth A.; Gregory, Don A.

2007-01-01

The strengths of two candidate glass types for use in a space observatory were measured. Samples of ultra-low expansion glass (ULE) and borosilicate (Pyrex) were tested in air and in vacuum at room temperature (20 degrees C) and in vacuum after being heated to 200 degrees C. Both glasses tested in vacuum showed a significant increase in strength over those tested in air. However, there was no statistical difference between the strength of samples tested in vacuum at room temperature and those tested in vacuum after heating to 200 degrees C.

N-H.N hydrogen bonding in 4,6-diphenyl-2-pyrimidinylamine isolated from the plant Justicia secunda (Acanthaceae).

PubMed

Gallagher, John F; Goswami, Shyamaprosad; Chatterjee, Baidyanath; Jana, Subrata; Dutta, Kalyani

2004-04-01

The title compound, C(16)H(13)N(3), isolated from Justicia secunda (Acanthaceae), comprises two molecules (which differ slightly in conformation) in the asymmetric unit of space group P-1. Intermolecular N(amino)-H.N(pyrm) interactions (N(pyrm) is a pyrimidine ring N atom) involve only one of the two donor amino H atoms and pyrimidine N atoms per molecule, forming dimeric units via R(2)(2)(8) rings, with N.N distances of 3.058 (2) and 3.106 (3) A, and N-H.N angles of 172.7 (18) and 175.8 (17) degrees. The dimers are linked by C-H.pi(arene) contacts, with an H.centroid distance of 2.77 A and a C-H.centroid angle of 141 degrees.

An open-framework thorium sulfate hydrate with 11.5 A voids.

PubMed

Wilson, Richard E; Skanthakumar, S; Knope, Karah E; Cahill, Christopher L; Soderholm, L

2008-10-20

We report the synthesis of a thorium sulfate hydrate with 11.5 A open channels that propagate through the structure. The compound crystallizes in the tetragonal space group P4(2)/nmc, a = b = 25.890(4) A, c = 9.080(2) A, Z = 8, V = 6086.3(2) A(3). The thermal stability of the compound was investigated using thermogravimetric analysis and high-energy X-ray scattering (HEXS) revealing that the compound begins to undergo decomposition near 200 degrees C with an accompanied loss in crystallinity. The immediate coordination environment about the thorium atoms remains intact through heating to 500 degrees C as demonstrated by HEXS. Further heating reveals the formation of at least two crystalline phases, Th(SO4)2 and ThO2, which ultimately decompose to ThO2.

Impact of diet on incisor growth and attrition and the development of dental disease in pet rabbits.

PubMed

Meredith, A L; Prebble, J L; Shaw, D J

2015-06-01

To assess the impact of four rabbit diets (hay only; extruded diet with hay; muesli with hay; muesli only) on length and curvature of cheek teeth and eruption and attrition rates of incisors. Thirty-two Dutch rabbits, randomly divided into four diet groups, had length and saggital plane curvature of the first cheek teeth measured radiographically at 1, 9 and 17 months. Eruption/attrition of the left upper incisor was directly measured at weeks 30, 32 and 35. Eruption rates matched attrition rates in all groups, but were higher in the hay only group than in both groups fed muesli. By month 9, a greater degree of tooth curvature was present in rabbits fed muesli only than in those fed hay only and extruded diet with hay. After 17 months, rabbits fed muesli only and muesli with hay had longer lower first cheek teeth and larger interdental spaces between the first two molars than rabbits fed extruded diet and hay and hay only. Three rabbits fed muesli only developed evidence of dental disease. Presence of increased tooth length, curvature and interdental spaces indicated early dental pathology in rabbits fed muesli. Muesli diets cannot be recommended for pet rabbits. © 2015 British Small Animal Veterinary Association.

Rhenium(V)-oxo complexes of neutral and monoanionic tetraazamacrocycles. X-ray structures of trans-oxohydroxo(1,4,8,11-tetraazacyclotetradecane)rhenium(V) bis(perchlorate)

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

Tsang, B.W.; Reibenspies, J.; Martell, A.E.

1993-03-17

The complexes of ReO[sub 2][sup +] and ReO(OH)[sup 2+] with 1,4,8,11-tetraazacyclotetradecane (cyclam) and 1,4,8,11-tetraazacyclotetradecan-2-one (O[sub 1]cyclam) have been synthesized and characterized. The complexes were prepared by ligand exchange reactions of the macrocycles with a variety of starting compounds including ReOCl[sub 3](PPh[sub 3])[sub 2] and ReO[sub 2](en)[sub 2]Cl. The ReO(OH)[sup 2+] complexes have been structurally characterized. ReO(OH)(H[sub [minus]1]O[sub 1]cyclam)ReO[sub 4] crystallizes in the monoclinic P2[sub 1]/n space group with a = 10.308(3) [Angstrom], b = 9.527(2) [Angstrom], c = 17.808(3) [Angstrom], and [beta] = 106.57(2)[degrees]. ReO(OH)(cyclam)(ClO[sub 4])[sub 2] crystallizes in the monoclinic C2/c space group with a = 9.734(4) [Angstrom], bmore » = 16.999(5) [Angstrom], c = 12.187(5) [Angstrom], and [beta] = 106.36[degrees]. The complex ReO(OH)(H[sub [minus]1]O[sub 1]cyclam)ReO[sub 4] has a distorted octahedral structure with one short ReO(oxo) bond and one long ReO(hydroxo) bond (1.685(8) vs 1.970(8) [Angstrom]). The deprotonated amide ReN(sp[sup 2]) bond is shorter than the other three ReN(sp[sup 3]) bond lengths (1.98(1) vs 2.13(3) [Angstrom] (average)). The structure of the ReO(OH)(cyclam)(ClO[sub 4])[sub 2] complex shows no distinction between the lengths of the two ReO(oxo and hydroxo) bonds (1.766(5) [Angstrom]) due to disorder of the oxo and hydroxo groups. Spectroscopic evidence is reported to confirm the presence of both oxo and hydroxo groups coordinated to rhenium. 38 refs., 7 figs., 6 tabs.« less

NASA's Webb Telescope "chilling out" in Houston for the summer

NASA Image and Video Library

2017-12-08

NASA’s James Webb Space Telescope was placed in Johnson Space Center’s historic Chamber A on June 20, 2017, to prepare for its final three months of testing in a cryogenic vacuum that mimics temperatures in space. Engineers will perform the test to prove that the telescope can operate in space at these temperatures. Chamber A will simulate an environment where the telescope will experience extreme cold -- around 37 Kelvin (minus 236 degrees Celsius or minus 393 degrees Fahrenheit). In space, the telescope must be kept extremely cold, in order to be able to detect the infrared light from very faint, distant objects. To protect the telescope from external sources of light and heat (like the sun, Earth, and moon), as well as from heat emitted by the observatory, a five-layer, tennis court-sized sunshield acts like a parasol that provides shade. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 400 degrees Fahrenheit) and a cold side (185 degrees below zero). The sunshield blocks sunlight from interfering with the sensitive telescope instruments. Read more: go.nasa.gov/2sZAilS NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Fluorescence-based classification of Caribbean coral reef organisms and substrates

USGS Publications Warehouse

Zawada, David G.; Mazel, Charles H.

2014-01-01

A diverse group of coral reef organisms, representing several phyla, possess fluorescent pigments. We investigated the potential of using the characteristic fluorescence emission spectra of these pigments to enable unsupervised, optical classification of coral reef habitats. We compiled a library of characteristic fluorescence spectra through in situ and laboratory measurements from a variety of specimens throughout the Caribbean. Because fluorescent pigments are not species-specific, the spectral library is organized in terms of 15 functional groups. We investigated the spectral separability of the functional groups in terms of the number of wavebands required to distinguish between them, using the similarity measures Spectral Angle Mapper (SAM), Spectral Information Divergence (SID), SID-SAM mixed measure, and Mahalanobis distance. This set of measures represents geometric, stochastic, joint geometric-stochastic, and statistical approaches to classifying spectra. Our hyperspectral fluorescence data were used to generate sets of 4-, 6-, and 8-waveband spectra, including random variations in relative signal amplitude, spectral peak shifts, and water-column attenuation. Each set consisted of 2 different band definitions: ‘optimally-picked’ and ‘evenly-spaced.’ The optimally-picked wavebands were chosen to coincide with as many peaks as possible in the functional group spectra. Reference libraries were formed from half of the spectra in each set and used for training purposes. Average classification accuracies ranged from 76.3% for SAM with 4 evenly-spaced wavebands to 93.8% for Mahalanobis distance with 8 evenly-spaced wavebands. The Mahalanobis distance consistently outperformed the other measures. In a second test, empirically-measured spectra were classified using the same reference libraries and the Mahalanobis distance for just the 8 evenly-spaced waveband case. Average classification accuracies were 84% and 87%, corresponding to the extremes in modeled water-column attenuation. The classification results from both tests indicate that a high degree of separability among the 15 fluorescent-spectra functional groups is possible using only a modest number of spectral bands.

Managing 'difficult emotions' and family life: exploring insights and social support within online self-management training.

PubMed

Sanders, C; Rogers, A; Gardner, C; Kennedy, A

2011-06-01

Previous research has demonstrated how the Internet can foster emotional support and provide a 'private' space for discussing sensitive issues. Whilst the family has been located as a primary source of support, empirical research on the dynamics of close personal relationships in chronic illness experience remains a challenge. To explore the role of family relationships in supporting self-care and the nature of social support exchanged within an online self-management training course. Qualitative thematic and narrative analysis of online discussion boards. Postings for 218 participants, divided between 11 groups were included for a course section that focused on 'difficult emotions'. Participants exchanged a high degree of emotional support and revealed much about their 'real life' relationships. The latter highlighted the complexities of managing illness within family contexts alongside additional pressures of daily life such as caring commitments and work roles. The private interactive space created within the course allowed insights into the dynamics of family life associated with illness management that are challenging to research. Simultaneously, collective support was developed amongst this group of predominantly working women. The article points to the implications for such interventions and associated evaluative research beyond this selective group.

Earth observation taken by the Expedition 33 crew.

NASA Image and Video Library

2012-10-21

ISS033-E-014658 (21 Oct. 2012) --- This photograph of Bhutan, taken by one of the Expedition 33 crew members aboard the International Space Station, shows a number of Himalayan peaks, glaciers and lakes. The space station was flying over a nadir point located at 28.3 degrees north latitude and 92.1 degrees east longitude when the image was recorded.

Gold(III) bis-thiosemicarbazonato complexes: synthesis, characterization, radiochemistry and X-ray crystal structure analysis.

PubMed

Bottenus, Brienne N; Kan, Para; Jenkins, Tyler; Ballard, Beau; Rold, Tammy L; Barnes, Charles; Cutler, Cathy; Hoffman, Timothy J; Green, Mark A; Jurisson, Silvia S

2010-01-01

A variety of (bis)thiosemicarbazone-based ligand systems have been investigated as chelating agents for Au(III) complexes with potential radiotherapeutic applications. Ligand systems containing an ethyl, propyl or butyl backbone between the two imine N donors have been synthesized to evaluate chelate ring size effects on the resultant Au(III) complex stability at the macroscopic and radiotracer levels. The Au(III) complexes were synthesized and characterized by NMR, electrospray ionization mass spectra, elemental analysis and X-ray crystallography. The (198)Au complexes were evaluated in vitro at the tracer level for stability in phosphate-buffered saline at pH 7.4 and 37 degrees C. One of these complexes [(198)Au(3,4-HxTSE)] showed high in vitro stability and was further evaluated in vivo in normal mice. [Au(ATSM)]AuCl(4).2CH(3)OH, (ATSM=diacetyl-bis(N(4)-methylthiosemicarbazone)) H(14)C(8)N(6)O(2)S(2)Cl(4)Au(2).2CH(3)OH, crystallized from methanol in the monoclinic space group P21/n with a=14.7293(13) A, b=7.7432(7) A, c=20.4363(18) A, beta=100.140(2) degrees, V=2294.4 (4) A(3), Z=4; [Au(3,4-HxTSE)]Cl.CH(3)CH(2)OH/AuCl(2), (3,4-HxTSE=3,4-hexanedione-bis(N(4)-ethylthiosemicarbazone)) H(26)C(13.6)N(6)O(0.8)S(2)Cl(1.2)Au(1.2), crystallized from ethanol in the monoclinic space group P21/c with a=10.1990(10) A, b=13.8833(14) A, c=15.1752(15) A, beta=99.353(2) degrees , V=2120.2 (4) A(3), Z=4. These studies revealed poor stability of the [(198)Au][Au(3,4-HxTSE)](+) complex; however, crystal structure data suggest potential alterations to the ligand backbone may increase stability. Copyright 2010 Elsevier Inc. All rights reserved.

Advanced degrees in astronautical engineering for the space industry

NASA Astrophysics Data System (ADS)

Gruntman, Mike

2014-10-01

Ten years ago in the summer of 2004, the University of Southern California established a new unique academic unit focused on space engineering. Initially known as the Astronautics and Space Technology Division, the unit operated from day one as an independent academic department, successfully introduced the full set of degrees in Astronautical Engineering, and was formally renamed the Department of Astronautical Engineering in 2010. The largest component of Department's educational programs has been and continues to be its flagship Master of Science program, specifically focused on meeting engineering workforce development needs of the space industry and government space research and development centers. The program successfully grew from a specialization in astronautics developed in mid-1990s and expanded into a large nationally-visible program. In addition to on-campus full-time students, it reaches many working students on-line through distance education. This article reviews the origins of the Master's degree program and its current status and accomplishments; outlines the program structure, academic focus, student composition, and enrollment dynamics; and discusses lessons learned and future challenges.

Space Station Freedom assembly and operation at a 51.6 degree inclination orbit

NASA Technical Reports Server (NTRS)

Troutman, Patrick A.; Brewer, Laura M.; Heck, Michael L.; Kumar, Renjith R.

1993-01-01

This study examines the implications of assembling and operating Space Station Freedom at a 51.6 degree inclination orbit utilizing an enhanced lift Space Shuttle. Freedom assembly is currently baselined at a 220 nautical mile high, 28.5 degree inclination orbit. Some of the reasons for increasing the orbital inclination are (1) increased ground coverage for Earth observations, (2) greater accessibility from Russian and other international launch sites, and (3) increased number of Assured Crew Return Vehicle (ACRV) landing sites. Previous studies have looked at assembling Freedom at a higher inclination using both medium and heavy lift expendable launch vehicles (such as Shuttle-C and Energia). The study assumes that the shuttle is used exclusively for delivering the station to orbit and that it can gain additional payload capability from design changes such as a lighter external tank that somewhat offsets the performance decrease that occurs when the shuttle is launched to a 51.6 degree inclination orbit.

Atlantis on Approach to ISS during the STS-132 Mission

NASA Image and Video Library

2010-05-16

ISS023-E-044528 (16 May 2010) --- Flying above coastal dunes along the Brazilian coast, the space shuttle Atlantis is shown making its relative approach to the International Space Station, from which this photo was taken. The city of Rutoia is close to the bay near the center of the image and the sandy meanders of the Rio Parnaiba. Center point coordinates of the image are 2.9 degrees south latitude and 42.2 degrees west longitude. Photo credit: NASA or National Aeronautics and Space Administration

Network Disruption in the Preclinical Stages of Alzheimer's Disease: From Subjective Cognitive Decline to Mild Cognitive Impairment.

PubMed

López-Sanz, David; Garcés, Pilar; Álvarez, Blanca; Delgado-Losada, María Luisa; López-Higes, Ramón; Maestú, Fernando

2017-12-01

Subjective Cognitive Decline (SCD) is a largely unknown state thought to represent a preclinical stage of Alzheimer's Disease (AD) previous to mild cognitive impairment (MCI). However, the course of network disruption in these stages is scarcely characterized. We employed resting state magnetoencephalography in the source space to calculate network smallworldness, clustering, modularity and transitivity. Nodal measures (clustering and node degree) as well as modular partitions were compared between groups. The MCI group exhibited decreased smallworldness, clustering and transitivity and increased modularity in theta and beta bands. SCD showed similar but smaller changes in clustering and transitivity, while exhibiting alterations in the alpha band in opposite direction to those showed by MCI for modularity and transitivity. At the node level, MCI disrupted both clustering and nodal degree while SCD showed minor changes in the latter. Additionally, we observed an increase in modular partition variability in both SCD and MCI in theta and beta bands. SCD elders exhibit a significant network disruption, showing intermediate values between HC and MCI groups in multiple parameters. These results highlight the relevance of cognitive concerns in the clinical setting and suggest that network disorganization in AD could start in the preclinical stages before the onset of cognitive symptoms.

Multivariate approach to quantitative analysis of Aphis gossypii Glover (Hemiptera: Aphididae) and their natural enemy populations at different cotton spacings.

PubMed

Malaquias, José B; Ramalho, Francisco S; Dos S Dias, Carlos T; Brugger, Bruno P; S Lira, Aline Cristina; Wilcken, Carlos F; Pachú, Jéssica K S; Zanuncio, José C

2017-02-09

The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation and release of its natural enemies. The aims of the study were (i) to characterize the temporal abundance data of aphids and its natural enemies using principal components, (ii) to analyze the degree of correlation between the insects and between groups of variables (pests and natural enemies), (iii) to identify the main natural enemies responsible for regulating A. gossypii populations, and (iv) to investigate the similarities in arthropod occurrence patterns at different spacings of cotton crops over two seasons. High correlations in the occurrence of Scymnus rubicundus with aphids are shown through principal component analysis and through the important role the species plays in canonical correlation analysis. Clustering the presence of apterous aphids matches the pattern verified for Chrysoperla externa at the three different spacings between rows. Our results indicate that S. rubicundus is the main candidate to regulate the aphid populations in all spacings studied.

Multivariate approach to quantitative analysis of Aphis gossypii Glover (Hemiptera: Aphididae) and their natural enemy populations at different cotton spacings

PubMed Central

Malaquias, José B.; Ramalho, Francisco S.; dos S. Dias, Carlos T.; Brugger, Bruno P.; S. Lira, Aline Cristina; Wilcken, Carlos F.; Pachú, Jéssica K. S.; Zanuncio, José C.

2017-01-01

The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation and release of its natural enemies. The aims of the study were (i) to characterize the temporal abundance data of aphids and its natural enemies using principal components, (ii) to analyze the degree of correlation between the insects and between groups of variables (pests and natural enemies), (iii) to identify the main natural enemies responsible for regulating A. gossypii populations, and (iv) to investigate the similarities in arthropod occurrence patterns at different spacings of cotton crops over two seasons. High correlations in the occurrence of Scymnus rubicundus with aphids are shown through principal component analysis and through the important role the species plays in canonical correlation analysis. Clustering the presence of apterous aphids matches the pattern verified for Chrysoperla externa at the three different spacings between rows. Our results indicate that S. rubicundus is the main candidate to regulate the aphid populations in all spacings studied. PMID:28181503

Multivariate approach to quantitative analysis of Aphis gossypii Glover (Hemiptera: Aphididae) and their natural enemy populations at different cotton spacings

NASA Astrophysics Data System (ADS)

Malaquias, José B.; Ramalho, Francisco S.; Dos S. Dias, Carlos T.; Brugger, Bruno P.; S. Lira, Aline Cristina; Wilcken, Carlos F.; Pachú, Jéssica K. S.; Zanuncio, José C.

2017-02-01

The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation and release of its natural enemies. The aims of the study were (i) to characterize the temporal abundance data of aphids and its natural enemies using principal components, (ii) to analyze the degree of correlation between the insects and between groups of variables (pests and natural enemies), (iii) to identify the main natural enemies responsible for regulating A. gossypii populations, and (iv) to investigate the similarities in arthropod occurrence patterns at different spacings of cotton crops over two seasons. High correlations in the occurrence of Scymnus rubicundus with aphids are shown through principal component analysis and through the important role the species plays in canonical correlation analysis. Clustering the presence of apterous aphids matches the pattern verified for Chrysoperla externa at the three different spacings between rows. Our results indicate that S. rubicundus is the main candidate to regulate the aphid populations in all spacings studied.

Derivatives of 1,5-diamino-1H-tetrazole: a new family of energetic heterocyclic-based salts.

PubMed

Gálvez-Ruiz, Juan Carlos; Holl, Gerhard; Karaghiosoff, Konstantin; Klapötke, Thomas M; Löhnwitz, Karolin; Mayer, Peter; Nöth, Heinrich; Polborn, Kurt; Rohbogner, Christoph J; Suter, Max; Weigand, Jan J

2005-06-13

1,5-Diamino-1H-tetrazole (2, DAT) can easily be protonated by reaction with strong mineral acids, yielding the poorly investigated 1,5-diaminotetrazolium nitrate (2a) and perchlorate (2b). A new synthesis for 2 is introduced that avoids lead azide as a hazardous byproduct. The reaction of 1,5-diamino-1H-tetrazole with iodomethane (7a) followed by the metathesis of the iodide (7a) with silver nitrate (7b), silver dinitramide (7c), or silver azide (7d) leads to a new family of heterocyclic-based salts. In all cases, stable salts were obtained and fully characterized by vibrational (IR, Raman) spectroscopy, multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, X-ray structure determination, and initial safety testing (impact and friction sensitivity). Most of the salts exhibit good thermal stabilities, and both the perchlorate (2b) and the dinitramide (7c) have melting points well below 100 degrees C, yet high decomposition onsets, defining them as new (7c), highly energetic ionic liquids. Preliminary sensitivity testing of the crystalline compounds indicates rather low impact sensitivities for all compounds, the highest being that of the perchlorate (2b) and the dinitramide (7c) with a value of 7 J. In contrast, the friction sensitivities of the perchlorate (2b, 60 N) and the dinitramide (7c, 24 N) are relatively high. The enthalpies of combustion (Delta(c)H degrees ) of 7b-d were determined experimentally using oxygen bomb calorimetry: Delta(c)H degrees (7b) = -2456 cal g(-)(1), Delta(c)H degrees (7c) = -2135 cal g(-)(1), and Delta(c)H degrees (7d) = -3594 cal g(-)(1). The standard enthalpies of formation (Delta(f)H degrees ) of 7b-d were obtained on the basis of quantum chemical computations using the G2 (G3) method: Delta(f)H degrees (7b) = 41.7 (41.2) kcal mol(-)(1), Delta(f)H degrees (7c) = 92.1 (91.1) kcal mol(-)(1), and Delta(f)H degrees (7d) = 161.6 (161.5) kcal mol(-)(1). The detonation velocities (D) and detonation pressures (P) of 2b and 7b-d were calculated using the empirical equations of Kamlet and Jacobs: D(2b) = 8383 m s(-)(1), P(2b) = 32.2 GPa; D(7b) = 7682 m s(-)(1), P(7b) = 23.4 GPa; D(7c) = 8827 m s(-)(1), P(7c) = 33.6 GPa; and D(7d) = 7405 m s(-)(1), P(7d) = 20.8 GPa. For all compounds, a structure determination by single-crystal X-ray diffraction was performed. 2a and 2b crystallize in the monoclinic space groups C2/c and P2(1)/n, respectively. The salts of 7 crystallize in the orthorhombic space groups Pna2(1) (7a, 7d) and Fdd2 (7b). The hydrogen-bonded ring motifs are discussed in the formalism of graph-set analysis of hydrogen-bond patterns and compared in the case of 2a, 2b, and 7b.

Random walk in degree space and the time-dependent Watts-Strogatz model

NASA Astrophysics Data System (ADS)

Casa Grande, H. L.; Cotacallapa, M.; Hase, M. O.

2017-01-01

In this work, we propose a scheme that provides an analytical estimate for the time-dependent degree distribution of some networks. This scheme maps the problem into a random walk in degree space, and then we choose the paths that are responsible for the dominant contributions. The method is illustrated on the dynamical versions of the Erdős-Rényi and Watts-Strogatz graphs, which were introduced as static models in the original formulation. We have succeeded in obtaining an analytical form for the dynamics Watts-Strogatz model, which is asymptotically exact for some regimes.

Random walk in degree space and the time-dependent Watts-Strogatz model.

PubMed

Casa Grande, H L; Cotacallapa, M; Hase, M O

2017-01-01

In this work, we propose a scheme that provides an analytical estimate for the time-dependent degree distribution of some networks. This scheme maps the problem into a random walk in degree space, and then we choose the paths that are responsible for the dominant contributions. The method is illustrated on the dynamical versions of the Erdős-Rényi and Watts-Strogatz graphs, which were introduced as static models in the original formulation. We have succeeded in obtaining an analytical form for the dynamics Watts-Strogatz model, which is asymptotically exact for some regimes.

Synthesis of graphene oxide through different oxidation degrees for solar cells

NASA Astrophysics Data System (ADS)

Zhang, Xiaoshan; Wang, Huan; Huang, Tianjiao; Wen, Lingling; Zhou, Liya

2018-03-01

Graphene is known as an electro-chemical material and widely used in electro-chemical devices, especially in solar cell. Decreasing the thickness of the layer is a critical way to improve the electrochemical property of solar cells as far as possible. Among the various oxidation approaches, presented herein is a facile approach, which is easier, less cost and more effective, environmental benign with the greener processing and without any requirement for post purification, towards the synthesis of graphene oxide (GO) with different oxidation degrees by potassium ferrate (K2FeO4). A modified method using less amount of oxidizing agent is reported herein. It is the pretreatment of the synthesis of graphite, which maintains the thermal cycle of the system. This novel reports to compound GO with controlled oxidation degrees can not only increase the quantity of oxygen-containing functional groups on GO surface, increase space between graphene oxide layer and facilitate the dispersion of graphene in aqueous solution. Thus, the modified method shows prospect for large-scale production of graphene oxide and its novel application, in addition to its derivative and market potential for solar cells.

Crystallization and preliminary X-ray analysis of a low density lipoprotein from human plasma.

PubMed

Prassl, R; Chapman, J M; Nigon, F; Sara, M; Eschenburg, S; Betzel, C; Saxena, A; Laggner, P

1996-11-15

Single crystals of human plasma low density lipoprotein (LDL), the major transport vehicle for cholesterol in blood, have been produced with a view to analysis of the three-dimensional structure by x-ray crystallography. Crystals with dimensions of approximately 200 x 100 x 50 microm have been reproducibly obtained from highly homogeneous LDL particle subspecies, isolated in the density ranges d = 1.0271-1. 0297 g/ml and d = 1.0297-1.0327 g/ml. Electron microscopic imaging of ultrathin-sectioned preparations of the crystals confirmed the existence of a regular, quasihexagonal arrangement of spherical particles of approximately 18 nm in diameter, thereby resembling the dimensions characteristic of LDL after dehydration and fixation. X-ray diffraction with synchrotron radiation under cryogenic conditions revealed the presence of well resolved diffraction spots, to a resolution of about 29 A. The diffraction patterns are indexed in terms of a triclinic lattice with unit cell dimensions of a = 16. 1 nm, b = 39.0 nm, c = 43.9 nm; alpha = 96.2 degrees, beta = 92.1 degrees, gamma = 102 degrees, and with space group P1.

Synthesis and characterization of new 19-vertex macropolyhedral boron hydrides.

PubMed

Dopke, J A; Powell, D R; Gaines, D F

2000-02-07

The new boron hydride anions 10-R-B19H19- (R = H, Thx) were synthesized by the reaction of M2[B18H20] (M = Na, K) with HBRCl.SMe2 (R = H, Thx) or HBCl2.SMe2 in diethyl ether. The anions are comprised of edge-sharing, nido 10- and 11-vertex cluster fragments, and are characterized by their 11B, 11B[1H], and 11B-11B COSY NMR spectra. The salt [(Ph3P)2N][B19H20].0.5THF crystallized in the triclinic space group P1 (a = 12.6344-(2) A, b = 13.5978(2) A, c = 14.1401(2) A; alpha = 77.402(2) degrees, beta = 81.351(2) degrees, gamma = 73.253(2) degrees). Possible synthetic pathways are discussed. The dianion B19H19(2-) is formed by deprotonation of B19H20- with Proton Sponge (1,8-bis(dimethylamino)naphthalene) in THF, and is identified on the basis of its 11B, 11B[1H], and 11B-11B COSY NMR spectra.

United States Changing Demographics - English/Spanish Space Education

NASA Astrophysics Data System (ADS)

Leon, R.

2002-01-01

Accordingly the United States Census Bureau, the ethnic group adding the largest number of people to the national population is the Hispanic exceeding 12 percent of the population and growing by almost 60 percent between 1990 and 2000. The status of the nation's educational system with respect to Hispanic students is perhaps one of the most influential issues facing the largest economy of the world. The low income, lack of language skills, highest drop-out rate in the nation, are some of the reasons why Hispanics are less likely to receive a university degree than any other ethical group. In short, the government requires to implement compensatory programs and bilingual education to ensure global leadership. Because of ongoing immigration, Spanish persists longer among Hispanics than it did among other immigrant groups. Spanish is the fourth most spoken language in the world after Mandarin, Hindustani and English. Although not all U.S. Hispanics speak Spanish, almost all U.S. Spanish speakers are Hispanics. This paper is intended to outline the challenging implementation of a bilingual education project affiliated to NASA Johnson Space Center encouraging greater academic success of Hispanics in engineering, math and science. The prospective project covers the overall role of space activities in the development of science and technology, socioeconomic issues and international cooperation. An existent JSC project is the starting stage to keep on developing an interactive video teleconference and web-media technology and produce stimulating learning products in English and Spanish for students and teachers across the nation and around the world.

Analysis on the propagation characteristics of two multiplexed groups of coaxial OAM beams in atmospheric turbulence

NASA Astrophysics Data System (ADS)

Zheng, Yongping; Tian, Qinghua; Zhang, Wei; Zhang, Qi; Zhu, Lei; Wang, Yongjun; Liu, Bo; Xin, Xiangjun

2018-01-01

Orbital angular momentum (OAM) as a new degree of freedom, greatly improves the spectrum efficiency and channel capacity of optical communication system. It has become the research focus in the field of optical communications. Some scholars have demonstrated that the feasibility of two multiplexed groups of concentric rings of Laguerre-Gaussian (LG) beams with OAM multiplexing transmission in free space. Based on the point, this paper makes the further research on the propagation characteristics of LG beams with this spatial multiplexing structure in atmospheric turbulence. The random phase screen is established by using the modified von Karman power spectrum and the received power and crosstalk power of OAM modes of LG beams are obtained under the Rytov approximation. We investigate the characteristic parameters of LG beams with this spatial multiplexing structure for mitigating turbulence. Simulation results show that the system exists an optimum beam waist related to wavelength in which the received power of OAM modes reaches the maximum. Meanwhile, the BER and aggregate capacity of the system with two multiplexed groups of concentric rings of LG beams with OAM multiplexing are simulated and analyzed under different intensities of atmospheric turbulence. The results reveal that the system with larger mode spacing generally has lower inter-modal crosstalk and larger aggregate capacity than that with the smaller mode spacing. Finally, on the basis of above the analysis and research, some suggestions for efficient OAM multiplexing detection scheme are proposed.

Synthesis and X-ray crystal structures of heavy-metal complexes of 1,5,9,13-tetrathiacyclohexadecane

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

Setzer, W.N.; Tang, Yaping; Grant, G.J.

1991-09-18

Heavy-metal complexes of the macrocyclic tetrathioether 1,5,9,13-tetrathiacyclohexadecane (16S4) have been prepared by reaction of the ligand with the appropriate heavy-metal salts. The complexes [Hg(16S4)](ClO[sub 4])[sub 2], [Cd(16S4)](ClO[sub 4])[sub 2], and (16S4)(HgCl[sub 2])[sub 2] have been synthesized and characterized. Single-crystal X-ray structural studies have been carried out on [Hg(16S4)](ClO[sub 4])[sub 2] and [Cd(16S4)](ClO[sub 4])[sub 2]. Crystal data for [Hg(16S4)](ClO[sub 4])[sub 2]: C[sub 12]H[sub 24]S[sub 4]HgCl[sub 2]O[sub 8]; monoclinic space group C2/c; a = 10.033 (3), b = 13.421 (4), c = 15.960 (4) [angstrom]; [beta] = 96.48 (2)[degree]; Z = 4; R = 0.051. Crystal data for [Cd(16S4)](ClO[sub 4])[sub 2]: C[submore » 12]H[sub 24]S[sub 4]CdCl[sub 2]O[sub 8]; triclinic space group P[bar I]; a = 8.346 (2), b = 8.349 (3), c = 8.688 (2) [angstrom]; [alpha] = 69.87 (2), [beta] = 68.97 (2), [gamma] = 82.33 (2)[degree]; Z = 1; R = 0.043. Molecular mechanics calculations have been carried out on the 16S4 ligand, and the lowest energy conformation is a quadrangular [4444] conformation with the sulfur atoms occupying the corners (exodentate) of the quadrangle.« less

Artificial Gravity as a Multi-System Countermeasure: Effects on Cognitive Function

NASA Technical Reports Server (NTRS)

Sipes, Walter E.; Seaton, Kim; Slack, Kellely; Bowie, Kendra

2007-01-01

The Space Flight Cognitive Assessment Tool for Windows (WinSCAT) is a medical requirement on the International Space Station, and its purpose is to evaluate cognitive functioning after physical insult (e.g., head trauma, decompression sickness, exposure to toxic gases, medication side effects). The current objective is to assess cognitive functioning in a long duration space mission analog environment where Artificial Gravity is being applied as a countermeasure in a Bed Rest study. Methods: Fifteen male subjects (8 treatment and 7 control) who participated in 21 days of -6 degree head-down bed rest were assessed. Three practice and three baseline WinSCAT test sessions were administered during the pre-bed rest phase of study participation. During the bed rest phase, the WinSCAT test was scheduled every other day, following the centrifuge, for a total of 10 test sessions. (The treatment group received 60 minutes of centrifugation each day during the 21 days of bed rest. The control subjects were strapped to the centrifuge for the same length of time as the treatment group but were not spun.) During the post-bed rest (reconditioning) phase, the test was administered 4 times. Results: Individual differences were found both within and between the treatment and control groups. After controlling for the number of subjects in each group, the treatment group accounted for more off-nominal WinSCAT scores than the control group. Conclusions:There is some preliminary evidence that centrifuge spinning might negatively impact cognitive functioning. However, due to sample size limitations, it cannot be ascertained whether there were significant differences in cognitive performance between the treatment and control groups. If centrifugation had a negative effect on cognitive functioning, consistent decrements would be expected to be found with all treatment subjects across time. Individual differences in underlying cognitive ability and motivation level are other possible explanations for the results found in this study.

Robonaut: a robot designed to work with humans in space

NASA Technical Reports Server (NTRS)

Bluethmann, William; Ambrose, Robert; Diftler, Myron; Askew, Scott; Huber, Eric; Goza, Michael; Rehnmark, Fredrik; Lovchik, Chris; Magruder, Darby

2003-01-01

The Robotics Technology Branch at the NASA Johnson Space Center is developing robotic systems to assist astronauts in space. One such system, Robonaut, is a humanoid robot with the dexterity approaching that of a suited astronaut. Robonaut currently has two dexterous arms and hands, a three degree-of-freedom articulating waist, and a two degree-of-freedom neck used as a camera and sensor platform. In contrast to other space manipulator systems, Robonaut is designed to work within existing corridors and use the same tools as space walking astronauts. Robonaut is envisioned as working with astronauts, both autonomously and by teleoperation, performing a variety of tasks including, routine maintenance, setting up and breaking down worksites, assisting crew members while outside of spacecraft, and serving in a rapid response capacity.

Robonaut: a robot designed to work with humans in space.

PubMed

Bluethmann, William; Ambrose, Robert; Diftler, Myron; Askew, Scott; Huber, Eric; Goza, Michael; Rehnmark, Fredrik; Lovchik, Chris; Magruder, Darby

2003-01-01

The Robotics Technology Branch at the NASA Johnson Space Center is developing robotic systems to assist astronauts in space. One such system, Robonaut, is a humanoid robot with the dexterity approaching that of a suited astronaut. Robonaut currently has two dexterous arms and hands, a three degree-of-freedom articulating waist, and a two degree-of-freedom neck used as a camera and sensor platform. In contrast to other space manipulator systems, Robonaut is designed to work within existing corridors and use the same tools as space walking astronauts. Robonaut is envisioned as working with astronauts, both autonomously and by teleoperation, performing a variety of tasks including, routine maintenance, setting up and breaking down worksites, assisting crew members while outside of spacecraft, and serving in a rapid response capacity.

Reduction of respiratory ghosting motion artifacts in conventional two-dimensional multi-slice Cartesian turbo spin-echo: which k-space filling order is the best?

PubMed

Inoue, Yuuji; Yoneyama, Masami; Nakamura, Masanobu; Takemura, Atsushi

2018-06-01

The two-dimensional Cartesian turbo spin-echo (TSE) sequence is widely used in routine clinical studies, but it is sensitive to respiratory motion. We investigated the k-space orders in Cartesian TSE that can effectively reduce motion artifacts. The purpose of this study was to demonstrate the relationship between k-space order and degree of motion artifacts using a moving phantom. We compared the degree of motion artifacts between linear and asymmetric k-space orders. The actual spacing of ghost artifacts in the asymmetric order was doubled compared with that in the linear order in the free-breathing situation. The asymmetric order clearly showed less sensitivity to incomplete breath-hold at the latter half of the imaging period. Because of the actual number of partitions of the k-space and the temporal filling order, the asymmetric k-space order of Cartesian TSE was superior to the linear k-space order for reduction of ghosting motion artifacts.

An in vitro evaluation of the degree of pulp tissue dissolution through different root canal irrigation protocols.

PubMed

Amato, Massimo; Pantaleo, Giuseppe; Abtellatif, Dina; Blasi, Andrea; Gagliani, Massimo; Iandolo, Alfredo

2018-01-01

The aim of this study is to evaluate in vitro , using artificial lateral canals, the rate of dissolution of the pulp tissue through different protocols of canal irrigation. One hundred artificial canals provided with lateral canals have been used. Each lateral canal was filled with pulp tissue and calibrated to 0.002 mg. All canals were irrigated using five different protocols. Five groups have been used for the experiment: Group A, distilled water (control); Group B, preheated NaOCl; Group C, NaOCl heated inside the canal; Group D, NaOCl ultrasonically activated; and Group E, NaOCl heated inside the canal with ultrasonic activation. All samples were weighed through professional microbalance in three different phases: before insertion of the pulp tissue into the lateral canal, after insertion of the pulp tissue and, finally, after different protocols of irrigation. A statistical analysis with Kruskal-Wallis test and Mann-Whitney test was performed. The partial dissolution of the pulp tissue inside the artificial lateral canal occurs only using the protocol with NaOCl heated inside the canal with ultrasonic activation. Other irrigation protocols are not able to dissolve the pulp tissue. The main objective of endodontic therapy is the removal of damaged tissues and bacteria. Modern literature highlights that it is impossible to remove all the pulp tissues and bacteria from the whole endodontic space. Hence, to achieve excellence and get positive results in the short and long term, it is necessary to use techniques and technologies that may increase the degree of root canal detersion.

Alternative Approaches to Mission Control Automation at NASA's Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Rackley, Michael; Cooter, Miranda; Davis, George; Mackey, Jennifer

2001-01-01

To meet its objective of reducing operations costs without incurring a corresponding increase in risk, NASA is seeking new methods to automate mission operations. This paper examines the state of the art in automating ground operations for space missions. A summary of available technologies and methods for automating mission operations is provided. Responses from interviews with several space mission FOTs (Flight Operations Teams) to assess the degree and success of those technologies and methods implemented are presented. Mission operators that were interviewed approached automation using different tools and methods resulting in varying degrees of success - from nearly completely automated to nearly completely manual. Two key criteria for successful automation are the active participation of the FOT in the planning, designing, testing, and implementation of the system and the relative degree of complexity of the mission.

Results of tests OA12 and IA9 in the Ames Research Center unitary plan wind tunnels on an 0.030-scale model of the space shuttle vehicle 2A to determine aerodynamic loads, volume 14

NASA Technical Reports Server (NTRS)

Spangler, R. H.

1974-01-01

Tests were conducted in wind tunnels during April and May 1973, on a 0.030-scale replica of the Space Shuttle Vehicle Configuration 2A. Aerodynamic loads data were obtained at Mach numbers from 0.6 to 3.5. The investigation included tests on the integrated (launch) configuration and the isolated orbiter (entry configuration). The integrated vehicle was tested at angles of attack and sideslip from -8 degrees to +8 degrees. The isolated orbiter was tested at angles of attack from -15 degrees to +40 degrees and angles of sideslip from -10 degrees to +10 degrees as dictated by trajectory considerations. The effects of orbiter/external tank incidence angle and deflected control surfaces on aerodynamic loads were also investigated. Tabulated pressure data were obtained for upper and lower wing surfaces and left and right vertical tail surfaces.

The effect of thermal treatment on the resistance of nickel-titanium rotary files in cyclic fatigue.

PubMed

Zinelis, Spiros; Darabara, Myrsini; Takase, Toshiyuki; Ogane, Kaoru; Papadimitriou, George D

2007-06-01

The purpose of this study was to determine the effect of various thermal treatments on the fatigue resistance of a nickel-titanium (NiTi) engine-driven endodontic file. Fifteen groups of 5 files each of ISO 30 and taper .04 were tested in this study. The cutting tip (5 mm from the end) of files from 14 groups were heat treated for 30 minutes in temperatures 250 degrees C, 300 degrees C, 350 degrees C, 375 degrees C, 400 degrees C, 410 degrees C, 420 degrees C, 425 degrees C, 430 degrees C, 440 degrees C, 450 degrees C, 475 degrees C, 500 degrees C, and 550 degrees C, respectively, while 1 group was used as reference. The files were placed in a device that allowed the instruments to be tested for rotating bending fatigue inside an artificial root canal. The number of rotations to breakage was recorded for each file. The mean values of all groups were statistically analyzed using 1-way analysis of variance and Student Newman Keuls multiple comparison test at alpha = .05. The 430 degrees C and 440 degrees C groups showed the highest values, with fatigue resistance decreasing for thermal treatment at lower and higher temperatures. This may be the result of metallurgical changes during annealing. Within the limitations of the low sample size and the specific instrument size tested, it appears that the appropriate thermal treatment may significantly increase the fatigue resistance of the NiTi file tested.

On direct theorems for best polynomial approximation

NASA Astrophysics Data System (ADS)

Auad, A. A.; AbdulJabbar, R. S.

2018-05-01

This paper is to obtain similarity for the best approximation degree of functions, which are unbounded in L p,α (A = [0,1]), which called weighted space by algebraic polynomials. {E}nH{(f)}p,α and the best approximation degree in the same space on the interval [0,2π] by trigonometric polynomials {E}nT{(f)}p,α of direct wellknown theorems in forms the average modules.

Association between mandibular third molar formation and retromolar space.

PubMed

Ghougassian, Saro S; Ghafari, Joseph G

2014-11-01

To assess the association between formation stages of the mandibular third molars and the space distal to the permanent molars (retromolar space). The material included pretreatment lateral cephalographs of 96 orthodontic patients (49 males, 47 females; 8-18 years old). The molar formation stage was assessed through the method of Nolla, which rates the degree of calcification on a scale of 10 stages. The retromolar space was measured from the most concave point of the anterior border of the ramus to the distal surface of the first molar (used because the second molars had not yet erupted in the younger patients). Statistical analyses included t-tests and analyses of variance for group differences and the Pearson product moment to gauge associations among variables. The formation stage advanced with age, but wide standard deviations were noted. Similarly, the retromolar distance increased with age and was greatest between 10 and 12 years. The correlation between retromolar space and developmental stage was high (r  =  0.85). On average, an increase of 5 mm of retromolar space corresponds to a 1.8 stage in tooth maturation. The correlation between third molar mineralization and available retromolar space essentially represents the association between one biologic age (dental formation) and another growth-related event (mandibular skeletal growth). The findings do not necessarily reflect successful emergence or nonimpaction of the molars. Longitudinal data are needed to determine such outcomes.

[Effectiveness of dorsal metacarpal island flap for treating scar contracture of finger web].

PubMed

Qian, Jun; Rui, Yongjun; Zhang, Quanrong; Xue, Mingyu; Zhang, Zhihai

2011-11-01

To investigate the effectiveness of dorsal metacarpal island flap for treating scar contracture of the finger web. Between June 2009 and December 2010, 10 patients with scar contracture of the finger web were treated. There were 6 males and 4 females with an average age of 30 years (range, 14-57 years). Scar contracture was caused by injury in 8 cases, by burn in 1 case, and by operation in 1 case. The locations were the 1st web space in 1 case, the 2nd web space in 3 cases, the 3rd web space in 5 cases, and the 4th web space in 1 case. The disease duration was 3 to 9 months with an average of 5 months. The maximum abduction was 10-20 degrees. After web space scar release, the dorsal metacarpal island flap (3.5 cm x 1.2 cm-4.0 cm x 2.0 cm in size) was used to reconstruct web space (2.0 cm x 1.0 cm-3.0 cm x 1.8 cm in size). The donor site was directly sutured or repaired with local flaps. At 2 days after operation, necrosis occurred in 1 flap, which healed by extractive treatment. The other flaps survived and wound healed by first intention; all the flaps at donor sites survived and incision healed by first intention. Ten patients were followed up 6 to 15 months (mean, 9 months). The reconstructed web space had good appearance, the maximum abduction was 80 degrees in 1 case of the 1st web space scars contracture, and the maximum abduction was 35-45 degrees (mean, 40 degrees) in the other 9 cases. In 8 scar patients causing by injury, no scar contracture recurred during follow-up. It can achieve good results in appearance and function to use dorsal metacarpal island flap for treating scar contracture of the finger web.

Center Planning and Development Student Engineer

NASA Technical Reports Server (NTRS)

Jenkins, Kenneth T.

2013-01-01

This fall I was the Student Trainee (Engineering) Pathways Intern (co-op) at the Kennedy Space Center (KSC) in the Center Planning Development (CPD) Directorate. CPD works with commercial companies who are interested using KSCs unique capabilities in spaceflight, spacecraft processing, ground systems and Research Development (RD) projects that fall in line with NASAs mission and goals. CPD is divided into four (4) groups: (1) AD-A, which works on the Master Planning for center, (2) AD-B (where I am), which works on project management and integration, (3) AD-C, which works on partnership development, and (4) AD-T, which works on the RD aspects of partnerships. CPDs main goal is to one day make KSC the worlds largest spaceport and maintain the center as a leader in space exploration. CPD is a very diverse group with employees having a wide knowledge of not only the Space Shuttle, but also that of the Apollo era. Our director of CPD, Scott Colloredo, is on the advisory board for Commercial Space Operations (CSO) and has a degree at ERAU. I worked on a number of different tasks for AD-B, as well as CPD, that includes, but not limited to: reviewing and reissuing engineering drawings from the Apollo and Shuttle eras, to supporting NASA rocket launches (MAVEN), and working on actual agreementsproposals that will be used in the partnership process with multiple partners. Most of the work I have done is sensitive information and cannot be disclosed.

High responsivity secondary ion energy analyzer

NASA Astrophysics Data System (ADS)

Belov, A. S.; Chermoshentsev, D. A.; Gavrilov, S. A.; Frolov, O. T.; Netchaeva, L. P.; Nikulin, E. S.; Zubets, V. N.

2018-05-01

The degree of space charge compensation of a 70 mA, 400 keV pulsed hydrogen ion beam has been measured with the use of an electrostatic energy analyzer of secondary ions. The large azimuthal angle of the analyzer enables a high responsivity, defined as the ratio of the slow secondary ion current emerging from the partially-compensated ion beam to the fast ion beam current. We measured 84% space charge compensation of the ion beam. The current from the slow ions and the rise time from the degree of space charge compensation were measured and compared with expected values.

Earth observations taken by the STS-9 crew

NASA Image and Video Library

2009-06-25

STS009-40-2575 (28 Nov-8 Dec 1983) --- This view of the Fuji volcano, Japan was taken on the 54th orbit of the Space Shuttle Columbia. The center coordinates are 35.5 degrees north latitude and 139.0 degrees east longitude. This was the first time a non-United States crew member was flown aboard the United States Space Shuttle, European Space Agency (ESA) payload specialist Ulf Merbold, Germany. The crew included NASA astronauts John W. Young, commander; Brewster H. Shaw Jr., pilot; Owen K. Garriott, mission specialist, Robert A. Parker, mission specialist; and Byron Lichtenberg, payload specialist.

Assessment of carotid stenosis using three-dimensional T2-weighted dark blood imaging: Initial experience.

PubMed

Mihai, Georgeta; Winner, Marshall W; Raman, Subha V; Rajagopalan, Sanjay; Simonetti, Orlando P; Chung, Yiu-Cho

2012-02-01

To evaluate the use of a T2-weighted SPACE sequence (T2w-SPACE) to assess carotid stenosis via several methods and compare its performance with contrast-enhanced magnetic resonance angiography (ceMRA). Fifteen patients with carotid atherosclerosis underwent dark blood (DB)-MRI using a 3D turbo spin echo with variable flip angles sequence (T2w-SPACE) and ceMRA. Images were coregistered and evaluated by two observers. Comparisons were made for luminal diameter, luminal area, degree of luminal stenosis (NASCET: North American Symptomatic Endarterectomy Trial; ECST: European Carotid Surgery Trial, and area stenosis), and vessel wall area. Degree of NASCET stenosis was clinically classified as mild (<50%), moderate (50%-69%), or severe (>69%). Excellent agreement was seen between ceMRA and T2w-SPACE and between observers for assessment of lumen diameter, lumen area, vessel wall area, and degree of NASCET stenosis (r > 0.80, P < 0.001). ECST stenosis was consistently higher than NASCET stenosis (48 ± 14% vs. 24 ± 22%, P < 0.001). Area stenosis (72 ± 2%) was significantly higher (P < 0.001) than both ESCT and NASCET stenosis. DB-MRI of carotid arteries using T2w-SPACE is clinically feasible. It provides accurate measurements of lumen size and degree of stenosis in comparison with ceMRA and offers a more reproducible measure of ECST stenosis than ceMRA. Copyright © 2011 Wiley Periodicals, Inc.

Cooling the Origins Space Telescope

NASA Technical Reports Server (NTRS)

Dipirro, M.; Canavan, E.; Fantano, L.

2017-01-01

The NASA Astrophysics Division has commissioned 4 studies for consideration by the 2020 Decadal Survey to be the next flagship mission following WFIRST (Wide Field Infrared Survey Telescope). One of the four studies is the Origins Space Telescope (OST), which will cover wavelengths from 6 microns to 600 microns. To perform at the level of the zodiacal, galactic, and cosmic background, the telescope must be cooled to 4 degrees Kelvin. 4 degrees Kelvin multi-stage mechanical cryocoolers will be employed along with a multilayer sunshield/thermal shield to achieve this temperature with a manageable parasitic heat load. Current state-of-the-art cryocoolers can achieve close to 4 degrees Kelvin, providing about 50 megawatts of cooling at 4 degrees Kelvin with an input power of 500 watts. Multiple coolers at this power level will be used in parallel. These coolers also provide extra cooling power at intermediate temperature stages of 15-20 degrees Kelvin and 50-70 degrees Kelvin . This upper stage cooling will be used to limit the heat conducted to 4 degrees Kelvin . The multi-layer sunshield will limit the radiated thermal energy to the 4 degrees Kelvin volume. This paper will describe the architecture of the cryogenic system for OST along with preliminary thermal models.

Transonic high Reynolds number stability and control characteristics of a 0.015-scale remotely controlled elevon model (44-0) of the space shuttle orbiter tested in calspan 8-foot TWT (LA70)

NASA Technical Reports Server (NTRS)

Parrell, H.; Gamble, J. D.

1977-01-01

Transonic Wind Tunnel tests were run on a .015 scale model of the space shuttle orbiter vehicle in the 8-foot transonic wind tunnel. Purpose of the test program was to obtain basic shuttle aerodynamic data through a full range of elevon and aileron deflections, verification of data obtained at other facilities, and effects of Reynolds number. Tests were performed at Mach numbers from .35 to 1.20 and Reynolds numbers from 3,500,000 to 8,200,000 per foot. The high Reynolds number conditions (nominal 8,000,000/foot) were obtained using the ejector augmentation system. Angle of attack was varied from -2 to +20 degrees at sideslip angles of -2, 0, and +2 degrees. Sideslip was varied from -6 to +8 degrees at constant angles of attack from 0 to +20 degrees. Aileron settings were varied from -5 to +10 degrees at elevon deflections of -10, 0, and +10 degrees. Fixed aileron settings of 0 and 2 degrees in combination with various fixed elevon settings between -20 and +5 degrees were also run at varying angles of attack.

Surgical Correction of Scoliosis in Patients With Duchenne Muscular Dystrophy: 30-Year Experience.

PubMed

Scannell, Brian P; Yaszay, Burt; Bartley, Carrie E; Newton, Peter O; Mubarak, Scott J

2017-12-01

The natural history of scoliosis in Duchenne muscular dystrophy (DMD) is progressive and debilitating if neglected. The purpose of this study was to evaluate outcomes related to spinal deformity surgery in patients with DMD over a 30-year period. This was a single center retrospective study of all operatively treated scoliosis in DMD patients over 30 years. Minimum follow-up was 2 years. Owing to changes in instrumentation over time, patients were divided into 2 groups: Luque or pedicle screws (PS) constructs. Radiographic, perioperative variables, pulmonary function test (preoperatively and postoperatively), and complication data were evaluated. There were 60 subjects (Luque: 47, PS: 13). The Luque group was on average 13 years old, 53 kg, and had 7 years of follow-up. Coronal Cobb was 31±12 degrees preoperatively, 16±11 degrees at first postoperatively, and 21±15 degrees at final follow-up (P≤0.001). Pelvic obliquity was 7±6 degrees preoperatively, 5±5 degrees at first postoperatively (P=0.43), and 5±4 degrees at final follow-up (P=0.77). The majority of this group was fused to L5 (45%) or the sacrum (49%). The PS group was on average 14 years old, 65 kg, and had 4 years of follow-up. Coronal Cobb was 43±19 degrees preoperatively, 12±9 degrees at first postoperatively (P≤0.001), and 12±8 degrees at final follow-up. Pelvic obliquity was 6±5 degrees preoperatively, 3±3 degrees at first postoperatively (P=0.06), and 2±2 degrees at final follow-up (P=0.053). The majority were fused to the pelvis (92%). Both groups' pulmonary function declined with time. Both groups had high complication rates (Luque 68%; PS group 54%). The Luque group had more implant-related complications (26%); the PS group had a higher rate of early postoperative infections (23%). Over a 30-year period of operative treatment of scoliosis in DMD, both PS constructs and Luque instrumentation improved coronal Cobb. The PS group had improved and maintained pelvic obliquity. Both groups had high complication rates. Level IV-therapeutic.

[Repairing severe cicatricial contracture deformity in web-space by kite-like incision combined with full-thickness skin grafting].

PubMed

Liang, Liming; Chai, Jiake; Jia, Xiaoming; Wang, Yirong; Meng, Suyu; Liu, Tao

2012-12-01

To investigate the effectiveness of repairing severe cicatricial contracture deformity in the web-space by kite-like incision combined with full-thickness skin grafting. Between June 2008 and September 2011, 31 patients (87 web-spaces) with severe cicatricial contracture deformities in the web-spaces were treated. There were 24 males and 7 females, aged 5-43 years (median, 22 years). The causes of injuries were flame burn (26 cases), scald (3 cases), electric arc burn (1 case), and chemical burn (1 case). The degree of burn was deep second degree (14 cases) and third degree (17 cases). The interval time from injury to operation was 10 months to 17 years (median, 2.2 years). The kite-like incision was marked on the scar in the web-space. The rhombic scar between the adjacent metacarpophalangeal joints was excised, and cicatricial contracture was released completely. The secondary wound in the web-space was repaired with full-thickness autogeneic skin grafting. The secondary wound at donor site was directly sutured. All full-thickness skin grafts survived well. The incisions at donor sites healed primarily. Of 31 patients, 29 (82 web-spaces) were followed up 6-18 months (mean, 13 months). The sizes and depths of reconstructed web-spaces were similar to those of normal ones. No secondary cicatricial contracture was observed, and the function of fingers recovered well. The short-term effectiveness is satisfactory by kite-like incision combined with full-thickness skin grafting for repairing severe cicatricial contracture deformities in the web-space, while the long-term effectiveness needs further observation.

Effect of ELEVON gap configurations on the longitudinal stability and control effectiveness of the 43-0 space shuttle orbiter (OA118)

NASA Technical Reports Server (NTRS)

Hughes, T.; Mennell, R.

1974-01-01

Experimental aerodynamic investigations were conducted on a stingmounted 0.0405-scale representation of the 140A/B space shuttle orbiter in a 7.75 by 11-Foot low speed wind tunnel from April 24 to April 26, 1974. Differential inboard/outboard elevon panel deflections with the 6-inch gap were investigated to determine outboard panel aileron effectiveness. The elevons were deflected from +20 degrees to -40 degrees in various combinations. Aerodynamic force and moment data for the orbiter were measured in the body axis system by an internally mounted, six-component strain gage balance. The model was sting mounted with the center of rotation located at F.S. 60.172. The angle of attack range was from -10 degrees to +24 degrees.

WFIRST: Science from Deep Field Surveys

NASA Astrophysics Data System (ADS)

Koekemoer, Anton M.; Foley, Ryan; WFIRST Deep Field Working Group

2018-06-01

WFIRST will enable deep field imaging across much larger areas than those previously obtained with Hubble, opening up completely new areas of parameter space for extragalactic deep fields including cosmology, supernova and galaxy evolution science. The instantaneous field of view of the Wide Field Instrument (WFI) is about 0.3 square degrees, which would for example yield an Ultra Deep Field (UDF) reaching similar depths at visible and near-infrared wavelengths to that obtained with Hubble, over an area about 100-200 times larger, for a comparable investment in time. Moreover, wider fields on scales of 10-20 square degrees could achieve depths comparable to large HST surveys at medium depths such as GOODS and CANDELS, and would enable multi-epoch supernova science that could be matched in area to LSST Deep Drilling fields or other large survey areas. Such fields may benefit from being placed on locations in the sky that have ancillary multi-band imaging or spectroscopy from other facilities, from the ground or in space. The WFIRST Deep Fields Working Group has been examining the science considerations for various types of deep fields that may be obtained with WFIRST, and present here a summary of the various properties of different locations in the sky that may be considered for future deep fields with WFIRST.

LOLA: Lunar Optical Long-baseline Array. 1992-1993 space design

NASA Technical Reports Server (NTRS)

Bronte, Daniel; Chaney, Joanne; Curran, Christine; Ferguson, Keith; Flint, Eric; Giunta, Tony; Knill, Duane; Levesque, Daniel; Lyon, Donald; Murphy, Sean

1993-01-01

In the fall of 1992, the design and analysis of a lunar-based optical interferometer telescope array was initiated by a group of students in the Department of Aerospace Engineering at Virginia Tech. This project was undertaken at the suggestion of the Space Exploration Initiative Office at the NASA Langley Research Center. The original array design requirements, listed below, centered on the primary objective of resolving earth-type planets about stars out to a distance of ten parsecs: spectrum coverage spanning wavelengths from five nm to five mm, with a primary operating mode in the visible spectrum; a total collecting area providing a signal-to-noise ratio (SNR) of no less than 10.0 for a median wavelength of 500 nm; the individual array elements must be identical and have a maximum optical diameter of 2.0 m; and lunar site selection is limited to ten degrees north and south of the lunar equator on the lunar far side while not closer than 15 degrees to either near-side limb. Following construction by astronaut crews, array operation will be conducted from earth and astronomical observations will not be conducted during the lunar day. The entire system is designed for minimum achievable mass. The majority of the original design requirements for the telescope array were met.

WFIRST: Science from Deep Field Surveys

NASA Astrophysics Data System (ADS)

Koekemoer, Anton; Foley, Ryan; WFIRST Deep Field Working Group

2018-01-01

WFIRST will enable deep field imaging across much larger areas than those previously obtained with Hubble, opening up completely new areas of parameter space for extragalactic deep fields including cosmology, supernova and galaxy evolution science. The instantaneous field of view of the Wide Field Instrument (WFI) is about 0.3 square degrees, which would for example yield an Ultra Deep Field (UDF) reaching similar depths at visible and near-infrared wavelengths to that obtained with Hubble, over an area about 100-200 times larger, for a comparable investment in time. Moreover, wider fields on scales of 10-20 square degrees could achieve depths comparable to large HST surveys at medium depths such as GOODS and CANDELS, and would enable multi-epoch supernova science that could be matched in area to LSST Deep Drilling fields or other large survey areas. Such fields may benefit from being placed on locations in the sky that have ancillary multi-band imaging or spectroscopy from other facilities, from the ground or in space. The WFIRST Deep Fields Working Group has been examining the science considerations for various types of deep fields that may be obtained with WFIRST, and present here a summary of the various properties of different locations in the sky that may be considered for future deep fields with WFIRST.

A case-association cluster detection and visualisation tool with an application to Legionnaires’ disease

PubMed Central

Sansom, P; Copley, V R; Naik, F C; Leach, S; Hall, I M

2013-01-01

Statistical methods used in spatio-temporal surveillance of disease are able to identify abnormal clusters of cases but typically do not provide a measure of the degree of association between one case and another. Such a measure would facilitate the assignment of cases to common groups and be useful in outbreak investigations of diseases that potentially share the same source. This paper presents a model-based approach, which on the basis of available location data, provides a measure of the strength of association between cases in space and time and which is used to designate and visualise the most likely groupings of cases. The method was developed as a prospective surveillance tool to signal potential outbreaks, but it may also be used to explore groupings of cases in outbreak investigations. We demonstrate the method by using a historical case series of Legionnaires’ disease amongst residents of England and Wales. PMID:23483594

Use of diphosphonates to correct disorders in calcium metabolism and mineral composition of bone tissue with 60-day hypokinesia in rats

NASA Technical Reports Server (NTRS)

Morukov, B. V.; Zaychik, V. YE.; Ivanov, V. M.; Orlov, O. I.

1988-01-01

Compounds of the diphosphonate group suppress bone resorption and bone tissue metabolism, from which it was assumed that they can be used for the prevention of osteoporosis and disorders of calcium homeostasis in humans during space flight. Two compounds of this group were used for preventive purposes in 60 day hypokinesia in rats. The results showed that diphosphonates have a marked effect on calcium metabolism and the condition of the bone tissues under conditions of long term hypokinesia: they reduce the content of ionized calcium in blood, delay the loss of calcium and phosphorus by the bone tissue, and to a considerable degree prevent reduction of bone density. This confirms the possibility of using compounds of this group for correcting and preventing changes of bone tissue and mineral metabolism during long term hypokinesia.

Six-degree-of-freedom active vibration isolation using a Stewart platform mechanism

NASA Technical Reports Server (NTRS)

Geng, Zheng; Haynes, Leonard S.

1993-01-01

The design and control problems of a class of multidegree-of-freedom vibration isolation systems (VISs) based on a Stewart platform mechanism are studied. A prototype of a six-degree-of-freedom VIS for precision control of a wide range of space-based structures implemented in Intelligent Automation, Inc. is described. The feasibility of using a Stewart platform to achieve 6-degree-of-freedom vibration control in space applications is shown. A new Terfenol-D actuator characterized by significantly longer stroke than any commercially available Terfenol-D actuator and direct flux and strain sensors integral to the actuator is described.

Robonaut: A Robotic Astronaut Assistant

NASA Technical Reports Server (NTRS)

Ambrose, Robert O.; Diftler, Myron A.

2001-01-01

NASA's latest anthropomorphic robot, Robonaut, has reached a milestone in its capability. This highly dexterous robot, designed to assist astronauts in space, is now performing complex tasks at the Johnson Space Center that could previously only be carried out by humans. With 43 degrees of freedom, Robonaut is the first humanoid built for space and incorporates technology advances in dexterous hands, modular manipulators, lightweight materials, and telepresence control systems. Robonaut is human size, has a three degree of freedom (DOF) articulated waist, and two, seven DOF arms, giving it an impressive work space for interacting with its environment. Its two, five fingered hands allow manipulation of a wide range of tools. A pan/tilt head with multiple stereo camera systems provides data for both teleoperators and computer vision systems.

Space infrared telescope facility wide field and diffraction limited array camera (IRAC)

NASA Technical Reports Server (NTRS)

Fazio, G. G.

1986-01-01

IRAC focal plane detector technology was developed and studies of alternate focal plane configurations were supported. While any of the alternate focal planes under consideration would have a major impact on the Infrared Array Camera, it was possible to proceed with detector development and optical analysis research based on the proposed design since, to a large degree, the studies undertaken are generic to any SIRTF imaging instrument. Development of the proposed instrument was also important in a situation in which none of the alternate configurations has received the approval of the Science Working Group.

Hierarchically partitioned nonlinear equation solvers

NASA Technical Reports Server (NTRS)

Padovan, Joseph

1987-01-01

By partitioning solution space into a number of subspaces, a new multiply constrained partitioned Newton-Raphson nonlinear equation solver is developed. Specifically, for a given iteration, each of the various separate partitions are individually and simultaneously controlled. Due to the generality of the scheme, a hierarchy of partition levels can be employed. For finite-element-type applications, this includes the possibility of degree-of-freedom, nodal, elemental, geometric substructural, material and kinematically nonlinear group controls. It is noted that such partitioning can be continuously updated, depending on solution conditioning. In this context, convergence is ascertained at the individual partition level.

Stress Prediction System

NASA Technical Reports Server (NTRS)

1995-01-01

NASA wanted to know how astronauts' bodies would react under various gravitational pulls and space suit weights. Under contract to NASA, the University of Michigan's Center for Ergonomics developed a model capable of predicting what type of stress and what degree of load a body could stand. The algorithm generated was commercialized with the ISTU (Isometric Strength Testing Unit) Functional Capacity Evaluation System, which simulates tasks such as lifting a heavy box or pushing a cart and evaluates the exertion expended. It also identifies the muscle group that limits the subject's performance. It is an effective tool of personnel evaluation, selection and job redesign.

Rhombohedral crystals of 2-dehydro-3-deoxygalactarate aldolase from Escherichia coli.

PubMed

Blackwell, N C; Cullis, P M; Cooper, R A; Izard, T

1999-07-01

2-Dehydro-3-deoxygalactarate (DDG) aldolase (E.C. 4.1.2.20) catalyzes the reversible aldol cleavage of DDG and 2-dehydro-3-deoxyglucarate to pyruvate and tartronic semialdehyde. Rhombohedral crystals of recombinant DDG aldolase from Escherichia coli K-12 were obtained. The crystals belong to space group R32 with unit-cell parameters a = 93 A, alpha = 85 degrees. The crystals diffract to beyond 1.8 A resolution on a Cu Kalpha rotating-anode generator. The asymmetric unit is likely to contain two molecules, corresponding to a packing density of 1.34 A3 Da-1.

[Evaluation of preparation of curved root canals using hand-used ProTaper].

PubMed

Nie, Min; Zhao, Xin-Chen; Peng, Bin; Fan, Ming-Wen; Bian, Zhuan

2009-05-01

To evaluate the shaping ability of hand-used ProTaper on curved canals using Endodontic Cube. Fifty-four curved root canals in vitro were selected and divided into three groups according to the curved degree (alpha), group A: 0 degrees < or = alpha < 25 degrees , group B: 25 degrees < or = alpha < 40 degrees , group C: 40 degrees < or = alpha < 55 degrees . Endodontic Cube was assembled, and each sample was sectioned perpendicular to the axis of the tooth into four sections with Isomer-Buhler in low speed. Then the root canals were prepared with hand-used ProTaper. Before and after shaping, photograph of all the sections were taken under a stereomicroscope. Statistical analyses were performed. The dentin cutting quantity of the whole canal prepared with ProTaper in group B and C was larger than that of group A. The deviation distance of the whole canal prepared by ProTaper in group C was significantly larger than that in group A, and the deviation distance in middle portion larger than that in group B. The maintaining ability in the middle portion of group C by ProTaper was worse than that of group A and B. The curvature of root canal may increase the cutting quantity of the -dentin and reduce the ability of remaining original canal shape prepared by ProTaper.

Still from High-Clouds Jupiter Movie

NASA Technical Reports Server (NTRS)

2000-01-01

This image is one of seven from the narrow-angle camera on NASA's Cassini spacecraft assembled as a brief movie of high-altitude cloud movements on Jupiter. It was taken in early October 2000.

The images were taken at a wavelength that is absorbed by methane, one chemical in Jupiter's lower clouds. So, dark areas are relatively free of high clouds, and the camera sees through to the methane in a lower level. Bright areas are places with high, thick clouds that shield the methane below.

The area shown covers latitudes from 50 degrees north to 50 degrees south and a 100-degree sweep of longitude.

Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

The design concept of the 6-degree-of-freedom hydraulic shaker at ESTEC

NASA Technical Reports Server (NTRS)

Brinkman, P. W.; Kretz, D.

1992-01-01

The European Space Agency (ESA) has decided to extend its test facilities at the European Space and Technology Center (ESTEC) at Noordwijk, The Netherlands, by implementing a 6-degree-of-freedom hydraulic shaker. This shaker will permit vibration testing of large payloads in the frequency range from 0.1 Hz to 100 Hz. Conventional single axis sine and random vibration modes can be applied without the need for a configuration change of the test set-up for vertical and lateral excitations. Transients occurring during launch and/or landing of space vehicles can be accurately simulated in 6-degrees-of-freedom. The performance requirements of the shaker are outlined and the results of the various trade-offs, which are investigated during the initial phase of the design and engineering program are provided. Finally, the resulting baseline concept and the anticipated implementation plan of the new test facility are presented.

Renormalization of position space amplitudes in a massless QFT

NASA Astrophysics Data System (ADS)

Todorov, Ivan

2017-03-01

Ultraviolet renormalization of position space massless Feynman amplitudes has been shown to yield associate homogeneous distributions. Their degree is determined by the degree of divergence while their order—the highest power of logarithm in the dilation anomaly—is given by the number of (sub)divergences. In the present paper we review these results and observe that (convergent) integration over internal vertices does not alter the total degree of (superficial) ultraviolet divergence. For a conformally invariant theory internal integration is also proven to preserve the order of associate homogeneity. The renormalized 4-point amplitudes in the φ4 theory (in four space-time dimensions) are written as (non-analytic) translation invariant functions of four complex variables with calculable conformal anomaly. Our conclusion concerning the (off-shell) infrared finiteness of the ultraviolet renormalized massless φ4 theory agrees with the old result of Lowenstein and Zimmermann [23].

Measurement of sea ice backscatter characteristics at 36 GHz using the surface contour radar

NASA Technical Reports Server (NTRS)

Fedor, L. S.; Walsh, E. J.

1985-01-01

Scattering studies of sea ice off the coast of Greenland were performed in January 1984 using the 36-GHz Surface Contour Radar (SCR) aboard the NASA P-3 aircraft. An oscillating mirror scans an actual half-power width of 0.96 degrees laterally to measure the surface at 51 evenly spaced points. By banking the aircraft, real-time topographical mapping and relative backscattered power are obtained at incidence angles between 0 and 30 degrees off-nadar, achieving at 175 m altitude a 2.9 by 4.4 m spatial resolution at nadir. With an aircraft ground speed of 100 m/s, 5-m successive scan line spacing and 1.8-m cross-track direction spacing is provided. By circling the aircraft in the 15 degree bank, the azimuthal anisotropy of the scattering is investigated along with the incidence angle dependence.

Adaptive control of space based robot manipulators

NASA Technical Reports Server (NTRS)

Walker, Michael W.; Wee, Liang-Boon

1991-01-01

For space based robots in which the base is free to move, motion planning and control is complicated by uncertainties in the inertial properties of the manipulator and its load. A new adaptive control method is presented for space based robots which achieves globally stable trajectory tracking in the presence of uncertainties in the inertial parameters of the system. A partition is made of the fifteen degree of freedom system dynamics into two parts: a nine degree of freedom invertible portion and a six degree of freedom noninvertible portion. The controller is then designed to achieve trajectory tracking of the invertible portion of the system. This portion consist of the manipulator joint positions and the orientation of the base. The motion of the noninvertible portion is bounded, but unpredictable. This portion consist of the position of the robot's base and the position of the reaction wheel.

Ballistic limit regression analysis for Space Station Freedom meteoroid and space debris protection system

NASA Technical Reports Server (NTRS)

Jolly, William H.

1992-01-01

Relationships defining the ballistic limit of Space Station Freedom's (SSF) dual wall protection systems have been determined. These functions were regressed from empirical data found in Marshall Space Flight Center's (MSFC) Hypervelocity Impact Testing Summary (HITS) for the velocity range between three and seven kilometers per second. A stepwise linear least squares regression was used to determine the coefficients of several expressions that define a ballistic limit surface. Using statistical significance indicators and graphical comparisons to other limit curves, a final set of expressions is recommended for potential use in Probability of No Critical Flaw (PNCF) calculations for Space Station. The three equations listed below represent the mean curves for normal, 45 degree, and 65 degree obliquity ballistic limits, respectively, for a dual wall protection system consisting of a thin 6061-T6 aluminum bumper spaced 4.0 inches from a .125 inches thick 2219-T87 rear wall with multiple layer thermal insulation installed between the two walls. Normal obliquity is d(sub c) = 1.0514 v(exp 0.2983 t(sub 1)(exp 0.5228). Forty-five degree obliquity is d(sub c) = 0.8591 v(exp 0.0428) t(sub 1)(exp 0.2063). Sixty-five degree obliquity is d(sub c) = 0.2824 v(exp 0.1986) t(sub 1)(exp -0.3874). Plots of these curves are provided. A sensitivity study on the effects of using these new equations in the probability of no critical flaw analysis indicated a negligible increase in the performance of the dual wall protection system for SSF over the current baseline. The magnitude of the increase was 0.17 percent over 25 years on the MB-7 configuration run with the Bumper II program code.

KENNEDY SPACE CENTER, FLA. - STS-82 crew members and workers at KSC's Vertical Processing Facility get a final look at the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) in its flight configuration for the STS-82 mission. The crew is participating in the Crew Equipment Integration Test (CEIT). NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument - its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is scheduled Feb. 11 aboard Discovery with a crew of seven.

NASA Image and Video Library

1997-01-22

KENNEDY SPACE CENTER, FLA. - STS-82 crew members and workers at KSC's Vertical Processing Facility get a final look at the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) in its flight configuration for the STS-82 mission. The crew is participating in the Crew Equipment Integration Test (CEIT). NICMOS is one of two new scientific instruments that will replace two outdated instruments on the Hubble Space Telescope (HST). NICMOS will provide HST with the capability for infrared imaging and spectroscopic observations of astronomical targets. The refrigerator-sized NICMOS also is HST's first cryogenic instrument - its sensitive infrared detectors must operate at very cold temperatures of minus 355 degrees Fahrenheit or 58 degrees Kelvin. NICMOS will be installed in Hubble during STS-82, the second Hubble Space Telescope servicing mission. Liftoff is scheduled Feb. 11 aboard Discovery with a crew of seven.

Ballistic limit regression analysis for Space Station Freedom meteoroid and space debris protection system

NASA Astrophysics Data System (ADS)

Jolly, William H.

1992-05-01

Relationships defining the ballistic limit of Space Station Freedom's (SSF) dual wall protection systems have been determined. These functions were regressed from empirical data found in Marshall Space Flight Center's (MSFC) Hypervelocity Impact Testing Summary (HITS) for the velocity range between three and seven kilometers per second. A stepwise linear least squares regression was used to determine the coefficients of several expressions that define a ballistic limit surface. Using statistical significance indicators and graphical comparisons to other limit curves, a final set of expressions is recommended for potential use in Probability of No Critical Flaw (PNCF) calculations for Space Station. The three equations listed below represent the mean curves for normal, 45 degree, and 65 degree obliquity ballistic limits, respectively, for a dual wall protection system consisting of a thin 6061-T6 aluminum bumper spaced 4.0 inches from a .125 inches thick 2219-T87 rear wall with multiple layer thermal insulation installed between the two walls. Normal obliquity is d(sub c) = 1.0514 v(exp 0.2983 t(sub 1)(exp 0.5228). Forty-five degree obliquity is d(sub c) = 0.8591 v(exp 0.0428) t(sub 1)(exp 0.2063). Sixty-five degree obliquity is d(sub c) = 0.2824 v(exp 0.1986) t(sub 1)(exp -0.3874). Plots of these curves are provided. A sensitivity study on the effects of using these new equations in the probability of no critical flaw analysis indicated a negligible increase in the performance of the dual wall protection system for SSF over the current baseline. The magnitude of the increase was 0.17 percent over 25 years on the MB-7 configuration run with the Bumper II program code.

Expanding the remarkable structural diversity of uranyl tellurites: hydrothermal preparation and structures of K[UO(2)Te(2)O(5)(OH)], Tl(3)[(UO(2))(2)[Te(2)O(5)(OH)](Te(2)O(6))].2H(2)O, beta-Tl(2)[UO(2)(TeO(3))(2)], and Sr(3)[UO(2)(TeO(3))(2)](TeO(3))(2).

PubMed

Almond, Philip M; Albrecht-Schmitt, Thomas E

2002-10-21

The reactions of UO(2)(C(2)H(3)O(2))(2).2H(2)O with K(2)TeO(3).H(2)O, Na(2)TeO(3) and TlCl, or Na(2)TeO(3) and Sr(OH)(2).8H(2)O under mild hydrothermal conditions yield K[UO(2)Te(2)O(5)(OH)] (1), Tl(3)[(UO(2))(2)[Te(2)O(5)(OH)](Te(2)O(6))].2H(2)O (2) and beta-Tl(2)[UO(2)(TeO(3))(2)] (3), or Sr(3)[UO(2)(TeO(3))(2)](TeO(3))(2) (4), respectively. The structure of 1 consists of tetragonal bipyramidal U(VI) centers that are bound by terminal oxo groups and tellurite anions. These UO(6) units span between one-dimensional chains of corner-sharing, square pyramidal TeO(4) polyhedra to create two-dimensional layers. Alternating corner-shared oxygen atoms in the tellurium oxide chains are protonated to create short/long bonding patterns. The one-dimensional chains of corner-sharing TeO(4) units found in 1 are also present in 2. However, in 2 there are two distinct chains present, one where alternating corner-shared oxygen atoms are protonated, and one where the chains are unprotonated. The uranyl moieties in 2 are bound by five oxygen atoms from the tellurite chains to create seven-coordinate pentagonal bipyramidal U(VI). The structures of 3 and 4 both contain one-dimensional [UO(2)(TeO(3))(2)](2-) chains constructed from tetragonal bipyramidal U(VI) centers that are bridged by tellurite anions. The chains differ between 3 and 4 in that all of the pyramidal tellurite anions in 3 have the same orientation, whereas the tellurite anions in 4 have opposite orientations on each side of the chain. In 4, there are also additional isolated TeO(3)(2-) anions present. Crystallographic data: 1, orthorhombic, space group Cmcm, a = 7.9993(5) A, b = 8.7416(6) A, c = 11.4413(8) A, Z = 4; 2, orthorhombic, space group Pbam, a = 10.0623(8) A, b = 23.024(2) A, c = 7.9389(6) A, Z = 4; 3, monoclinic, space group P2(1)/n, a = 5.4766(4) A, b = 8.2348(6) A, c = 20.849(3) A, beta = 92.329(1) degrees, Z = 4; 4, monoclinic, space group C2/c, a = 20.546(1) A, b = 5.6571(3) A, c = 13.0979(8) A, beta = 94.416(1) degrees, Z = 4.

Fermionic influence on inflationary fluctuations

NASA Astrophysics Data System (ADS)

Boyanovsky, Daniel

2016-04-01

Motivated by apparent persistent large scale anomalies in the cosmic microwave background we study the influence of fermionic degrees of freedom on the dynamics of inflaton fluctuations as a possible source of violations of (nearly) scale invariance on cosmological scales. We obtain the nonequilibrium effective action of an inflaton-like scalar field with Yukawa interactions (YD ,M) to light fermionic degrees of freedom both for Dirac and Majorana fields in de Sitter space-time. The effective action leads to Langevin equations of motion for the fluctuations of the inflaton-like field, with self-energy corrections and a stochastic Gaussian noise. We solve the Langevin equation in the super-Hubble limit implementing a dynamical renormalization group resummation. For a nearly massless inflaton its power spectrum of super-Hubble fluctuations is enhanced, P (k ;η )=(H/2 π )2eγt[-k η ] with γt[-k η ]=1/6 π2 [∑i =1 NDYi,D 2+2 ∑j =1 NMYj,M 2]{ln2[-k η ]-2 ln [-k η ]ln [-k η0]} for ND Dirac and NM Majorana fermions, and η0 is the renormalization scale at which the inflaton mass vanishes. The full power spectrum is shown to be renormalization group invariant. These corrections to the super-Hubble power spectrum entail a violation of scale invariance as a consequence of the coupling to the fermionic fields. The effective action is argued to be exact in the limit of a large number of fermionic fields. A cancellation between the enhancement from fermionic degrees of freedom and suppression from light scalar degrees of freedom conformally coupled to gravity suggests the possibility of a finely tuned supersymmetry among these fields.

Exact renormalization group in Batalin-Vilkovisky theory

NASA Astrophysics Data System (ADS)

Zucchini, Roberto

2018-03-01

In this paper, inspired by the Costello's seminal work [11], we present a general formulation of exact renormalization group (RG) within the Batalin-Vilkovisky (BV) quantization scheme. In the spirit of effective field theory, the BV bracket and Laplacian structure as well as the BV effective action (EA) depend on an effective energy scale. The BV EA at a certain scale satisfies the BV quantum master equation at that scale. The RG flow of the EA is implemented by BV canonical maps intertwining the BV structures at different scales. Infinitesimally, this generates the BV exact renormalization group equation (RGE). We show that BV RG theory can be extended by augmenting the scale parameter space R to its shifted tangent bundle T [1]ℝ. The extra odd direction in scale space allows for a BV RG supersymmetry that constrains the structure of the BV RGE bringing it to Polchinski's form [6]. We investigate the implications of BV RG supersymmetry in perturbation theory. Finally, we illustrate our findings by constructing free models of BV RG flow and EA exhibiting RG supersymmetry in the degree -1 symplectic framework and studying the perturbation theory thereof. We find in particular that the odd partner of effective action describes perturbatively the deviation of the interacting RG flow from its free counterpart.

Distributed interactive communication in simulated space-dwelling groups.

PubMed

Brady, Joseph V; Hienz, Robert D; Hursh, Steven R; Ragusa, Leonard C; Rouse, Charles O; Gasior, Eric D

2004-03-01

This report describes the development and preliminary application of an experimental test bed for modeling human behavior in the context of a computer generated environment to analyze the effects of variations in communication modalities, incentives and stressful conditions. In addition to detailing the methodological development of a simulated task environment that provides for electronic monitoring and recording of individual and group behavior, the initial substantive findings from an experimental analysis of distributed interactive communication in simulated space dwelling groups are described. Crews of three members each (male and female) participated in simulated "planetary missions" based upon a synthetic scenario task that required identification, collection, and analysis of geologic specimens with a range of grade values. The results of these preliminary studies showed clearly that cooperative and productive interactions were maintained between individually isolated and distributed individuals communicating and problem-solving effectively in a computer-generated "planetary" environment over extended time intervals without benefit of one another's physical presence. Studies on communication channel constraints confirmed the functional interchangeability between available modalities with the highest degree of interchangeability occurring between Audio and Text modes of communication. The effects of task-related incentives were determined by the conditions under which they were available with Positive Incentives effectively attenuating decrements in performance under stressful time pressure. c2003 Elsevier Ltd. All rights reserved.

Administration of recombinant interleukin-11 improves the hemodynamic functions and decreases third space fluid loss in a porcine model of hemorrhagic shock and resuscitation.

PubMed

Honma, Kaneatsu; Koles, Nancy L; Alam, Hasan B; Rhee, Peter; Rollwagen, Florence M; Olsen, Cara; Keith, James C; Pollack, Matthew

2005-06-01

We have previously demonstrated that the administration of recombinant human interleukin-11 (rhIL-11) during resuscitation improves the blood pressure in a rodent model of hemorrhagic shock. The purpose of this study was to determine whether the effects of rhIL-11 could be reproduced in a large animal model and to elucidate the impact of rhIL-11 administration on the intravascular volume status and the degree of third space fluid loss after resuscitation. A 40% blood volume hemorrhage was induced in swine (n = 45, weight of 25-35 kg) followed by a 1-h shock period and resuscitation with 0.9% sodium chloride (three times the shed blood volume). The animals were randomized to receive sham hemorrhage (group I, sham); sham hemorrhage and 50 microg/kg rhIL-11 (group II, sham + IL-11); no drug (group III, saline); or 50 microg/kg rhIL-11 (group IV, IL-11). Blood and urine samples were obtained and analyzed at baseline, at the end of hemorrhaging, and thereafter once every hour. The pleural and peritoneal effusions were precisely quantified by using clinically accepted criteria. The mean arterial pressure (MAP) was higher postresuscitation (PR) in groups I, II, and IV (71.4 +/- 7.5 mmHg, 71.0 +/- 8.9 mmHg, and 72.9 +/- 12.3 mmHg, respectively) than in group III (59.9 +/- 10.9 mmHg), and the cardiac output of PR was higher in group IV (3.46 +/- 0.56 L/min) than in group III (2.99 +/- 0.62 L/min; P < 0.01). The difference in MAP between groups I and II became statistically significant at 40 min after rhIL-11 injection and such a difference persisted for 90 min. After resuscitation, the urine output was higher, and the urine specific gravity and third space fluid loss were lower in group IV (1434 +/- 325 mL and 1.0035, 82 +/- 21 mL) than in group III (958 +/- 390 mL and 1.0053, 125 +/- 32 mL; P < 0.05). In a porcine model of hemorrhagic shock, the administration of rhIL-11 at the start of resuscitation significantly improved the cardiac output and blood pressure. This strategy also significantly reduced the extent of third space fluid losses while also having a favorable impact on the intravascular volume status as evidenced by the improved urine output.

Noncommutative coherent states and related aspects of Berezin-Toeplitz quantization

NASA Astrophysics Data System (ADS)

Hasibul Hassan Chowdhury, S.; Twareque Ali, S.; Engliš, Miroslav

2017-05-01

In this paper, we construct noncommutative coherent states using various families of unitary irreducible representations (UIRs) of Gnc , a connected, simply connected nilpotent Lie group, which was identified as the kinematical symmetry group of noncommutative quantum mechanics for a system of two degrees of freedom in an earlier paper. Similarly described are the degenerate noncommutative coherent states arising from the degenerate UIRs of Gnc . We then compute the reproducing kernels associated with both these families of coherent states and study the Berezin-Toeplitz quantization of the observables on the underlying 4-dimensional phase space, analyzing in particular the semi-classical asymptotics for both these cases. Dedicated by the first and the third authors to the memory of the second author, with gratitude for his friendship and for all they learnt from him.

Differential characters and cohomology of the moduli of flat connections

NASA Astrophysics Data System (ADS)

Castrillón López, Marco; Ferreiro Pérez, Roberto

2018-05-01

Let π {:} P→ M be a principal bundle and p an invariant polynomial of degree r on the Lie algebra of the structure group. The theory of Chern-Simons differential characters is exploited to define a homology map χ k {:} H_{2r-k-1}(M)× Hk(F/G)→ R/Z , for k

Magnetic resonance imaging features of Great Danes with and without clinical signs of cervical spondylomyelopathy

PubMed Central

Martin-Vaquero, Paula; da Costa, Ronaldo C.

2014-01-01

Objective To characterize and compare the MRI morphological features of the cervical vertebral column of Great Danes with and without clinical signs of cervical spondylomyelopathy (CSM). Design Prospective cohort study. Animals 30 Great Danes (15 clinically normal and 15 CSM-affected). Procedures All dogs underwent MRI of the cervical vertebral column (C2–3 through T1–2). Features evaluated included sites of subarachnoid space compression, spinal cord compression, or both; degree, cause, and direction of compression; MRI signal changes of the spinal cord; articular process (facet) joint characteristics; internal vertebral venous plexus visibility; and presence of extradural synovial cysts as well as presence and degree of intervertebral disk degeneration and foraminal stenosis. Results Clinically normal and CSM-affected dogs had 11 and 61 compressive sites, respectively, detected with MRI. All CSM-affected dogs had ≥ 1 site of spinal cord compression. No signal changes were observed in spinal cords of normal dogs, whereas 14 sites of hyperintensity were found in 9 CSM-affected dogs. Foraminal stenosis was present in 11 clinically normal and all CSM-affected dogs. The number of stenotic foraminal sites was significantly greater in the CSM-affected group, and severe stenosis appeared to be more common in this group than in the clinically normal group. Significant differences were identified between clinically normal and CSM-affected dogs with regard to amount of synovial fluid evident, regularity of articular surfaces, degree of articular process joint proliferation, and internal vertebral venous plexus visibility. Conclusions and Clinical Relevance Abnormalities were detected with MRI in several clinically normal Great Danes. Severe spinal cord compression, number of stenotic foraminal sites, and signal changes within the spinal cord distinguished CSM-affected from clinically normal Great Danes. PMID:25075822

Magnetic resonance imaging features of Great Danes with and without clinical signs of cervical spondylomyelopathy.

PubMed

Martin-Vaquero, Paula; da Costa, Ronaldo C

2014-08-15

To characterize and compare the MRI morphological features of the cervical vertebral column of Great Danes with and without clinical signs of cervical spondylomyelopathy (CSM). Prospective cohort study. 30 Great Danes (15 clinically normal and 15 CSM-affected). All dogs underwent MRI of the cervical vertebral column (C2-3 through T1-2). Features evaluated included sites of subarachnoid space compression, spinal cord compression, or both; degree, cause, and direction of compression; MRI signal changes of the spinal cord; articular process (facet) joint characteristics; internal vertebral venous plexus visibility; and presence of extradural synovial cysts as well as presence and degree of intervertebral disk degeneration and foraminal stenosis. Clinically normal and CSM-affected dogs had 11 and 61 compressive sites, respectively, detected with MRI. All CSM-affected dogs had ≥ 1 site of spinal cord compression. No signal changes were observed in spinal cords of normal dogs, whereas 14 sites of hyperintensity were found in 9 CSM-affected dogs. Foraminal stenosis was present in 11 clinically normal and all CSM-affected dogs. The number of stenotic foraminal sites was significantly greater in the CSM-affected group, and severe stenosis appeared to be more common in this group than in the clinically normal group. Significant differences were identified between clinically normal and CSM-affected dogs with regard to amount of synovial fluid evident, regularity of articular surfaces, degree of articular process joint proliferation, and internal vertebral venous plexus visibility. Abnormalities were detected with MRI in several clinically normal Great Danes. Severe spinal cord compression, number of stenotic foraminal sites, and signal changes within the spinal cord distinguished CSM-affected from clinically normal Great Danes.

[Case-control study on bone setting manipulation for the treatment of over degree II supination-eversion fractures of ankle joint].

PubMed

Qi, Yue-Feng; Chen, Fa-Lin; Bao, Shu-Ren; Li, Cheng-Huan; Zhao, Xing-Wei; Liu, Shi-Ming; Chen, Wen-Xue; Li, Ye; Wang, Peng

2012-08-01

To explore therapeutic effects of bone setting manipulation for the treatment of over degree II supination-eversion fractures of ankle,and analyze manipulative reduction mechanism. From 2005 to 2008, 95 patients with over degree II supination-eversion fractures of ankle were treated respectively by manipulation and operation. There were 43 cases [11 males and 32 females with an average age of (44.95 +/- 12.65) years] in manipulation group, and 2 cases were degree II, 11 cases were degree III, and 30 cases were degree IV. There were 52 cases [21 males and 31 females with an average age of (39.96 +/- 13.28) years] in operative group,and 6 cases were degree II, 18 cases were degree III, and 28 cases were degree IV. Bone setting manipulation and hard splint external fixation were applied to manipulative group. Operative reduction internal fixation was performed in operative group. X-ray was used to evaluate reduction of fracture before and after treatment, 2 months after treatment. Ankle joint function was evaluated according to Olerud-Molander scoring system after 6 months treatment. All patients were followed up with good reduction. Three cases occurred wound complication in operative group, but not in manipulative group. In manipulation group, 19 cases got excellent results, 20 cases good and 4 cases fair; while in operative group, 30 cases got excellent results, 20 cases good and 2 cases poor. There were no significant differences in fracture reduction and ankle joint function recovery between two groups (P > 0.05). Efficacy of operative treatment was better than that of manipulative treatment at degree IV fracture (P < 0.05). Bone setting manipulation is a good method for treating supination-eversion ankle joint fractures, which has advantages of simple and safe operation, reliable efficacy. For ankle join fracture at degree IV, manipulative reduction should be adopted earlier, and operative treatment also necessary

Optimal wrist angulation shortens time needed for radial artery catheterization: a prospective, randomized, and blinded study.

PubMed

Pandey, R; Ashraf, H; Bhalla, A P; Garg, R

2012-01-01

Optimal wrist position is essential for successful catheterization of the radial artery. We planned to study the success rate of radial artery catheterization at various degrees of wrist extension angulations. This prospective, randomized study was performed in 60 consenting patients aged between 18-65 years and undergoing variable surgeries where the anesthetic management required an arterial catheterization. All patients were randomized into three groups of 20 patients each, according to wrist angulation during radial artery catheterization : either 30 degrees (Group 30), 45 degrees (Group 45), or 60 degrees (Group 60). Three metallic angulated wrist boards with angles of 30 degrees, 45 degrees, and 60 degrees (angle measured with calipers) were prepared, on which patient's wrist was kept at the above-mentioned angles of extension. Radial artery catheterization success rate, catheterization time, and numbers of attempts were recorded. The catheterization time was minimal in group 45 (30.50 +/- 16.82 sec) as compared to 36.00 +/- 14.19 sec and 43.50 +/- 13.80 sec in group 30 and 60, respectively. Radial artery was catheterized at first attempt in 60% of Group 45 and Group 60 patients, and in 50% of Group 30 patients. The arterial catheterization was successful in 14/20 patients in Group 30, 19/20 patients in group 45, and 16/20 patients in group 60. We conclude that a wrist extension of 450 appears to be the optimal wrist joint extension for a successful radial artery cannula insertion.

Demography-based adaptive network model reproduces the spatial organization of human linguistic groups

NASA Astrophysics Data System (ADS)

Capitán, José A.; Manrubia, Susanna

2015-12-01

The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space.

Demography-based adaptive network model reproduces the spatial organization of human linguistic groups.

PubMed

Capitán, José A; Manrubia, Susanna

2015-12-01

The distribution of human linguistic groups presents a number of interesting and nontrivial patterns. The distributions of the number of speakers per language and the area each group covers follow log-normal distributions, while population and area fulfill an allometric relationship. The topology of networks of spatial contacts between different linguistic groups has been recently characterized, showing atypical properties of the degree distribution and clustering, among others. Human demography, spatial conflicts, and the construction of networks of contacts between linguistic groups are mutually dependent processes. Here we introduce an adaptive network model that takes all of them into account and successfully reproduces, using only four model parameters, not only those features of linguistic groups already described in the literature, but also correlations between demographic and topological properties uncovered in this work. Besides their relevance when modeling and understanding processes related to human biogeography, our adaptive network model admits a number of generalizations that broaden its scope and make it suitable to represent interactions between agents based on population dynamics and competition for space.

Comparative techniques of medial rectus muscle retraction for endoscopic exposure of the medial intraconal space.

PubMed

Lin, Giant C; Freitag, Suzanne K; Kocharyan, Armine; Yoon, Michael K; Lefebvre, Daniel R; Bleier, Benjamin S

2016-05-01

The medial rectus muscle (MRM) is the medial boundary to the intraconal space of the orbit, and retraction of the MRM is oftentimes necessary for endoscopic removal of intraconal tumors, e.g., orbital hemangioma. We evaluated each of the reported methods of MRM retraction for endoscopic orbital surgery and quantified the degree of intraconal exposure conferred by each method. Eight orbits from four cadaver heads were dissected. In each orbit, medial orbital decompression was performed and the MRM was retracted by using four previously described techniques: (1) external MRM retraction at the globe insertion point by using vessel loop (external group), (2) transseptal MRM retraction by using vessel loop (transseptal group), (3) transchoanal retraction of the MRM by using vessel loop (choanal group), and (4) transseptal four-handed technique by using double ball retraction by a second surgeon (transseptal double ball group). The length, height, and area of exposure of the medial intraconal space were quantified and compared. The average ± standard deviation (SD) anterior-posterior exposures for the external group, transseptal group, and transseptal double ball group were 17.51 ± 3.39 mm, 16.59 ± 4.16 mm, and 18.0 ± 15.25 mm, respectively. The choanal group provided significantly less exposure (12.39 ± 3.44 mm, p = 0.049) than the other groups. The average ± SD vertical exposures for the transseptal group, choanal group, and transseptal double ball group were 12.53 ± 4.38 mm, 13.05 ± 5.86 mm, and 13.57 ± 3.74 mm, respectively. The external group provided significantly less exposure (4.51 ± 1.56 mm, p = 0.0072) than the other groups. The transseptal and transseptal double ball groups provided the greatest total access by surface area (58.88 ± 26.96 mm(2) and 62.94 ± 34.74 mm(2), respectively) compared with the external and choanal groups (34.82 ± 23.37 mm(2) and 43.10 ± 23.68 mm(2), respectively). Although the transseptal trajectory of MRM retraction was optimal, the difference in total area of exposure between the static vessel loop retraction and the dynamic, four-handed technique with double ball instrument retraction was not significant. Of note, the exposure provided by the choanal technique required the surgeon to work both above and below the muscle. Retraction of the MRM toward the choanae provided the least length of exposure, and external retraction exposed the least height and total area. Transseptal MRM retraction was most favorable and provided the largest endoscopic corridor to the medial intraconal space. A four-handed approach for endoscopic intraconal surgery of the orbit may offer advantages in dynamic adjustments in retraction.

Highlights from the First Ever Demographic Study of Solar Physics, Space Physics, and Upper Atmospheric Physics

NASA Astrophysics Data System (ADS)

Moldwin, M.; Morrow, C. A.; White, S. C.; Ivie, R.

2014-12-01

Members of the Education & Workforce Working Group and the American Institute of Physics (AIP) conducted the first ever National Demographic Survey of working professionals for the 2012 National Academy of Sciences Solar and Space Physics Decadal Survey to learn about the demographics of this sub-field of space science. The instrument contained questions for participants on: the type of workplace; basic demographic information regarding gender and minority status, educational pathways (discipline of undergrad degree, field of their PhD), how their undergraduate and graduate student researchers are funded, participation in NSF and NASA funded spaceflight missions and suborbital programs, and barriers to career advancement. Using contact data bases from AGU, the American Astronomical Society's Solar Physics Division (AAS-SPD), attendees of NOAA's Space Weather Week and proposal submissions to NSF's Atmospheric, Geospace Science Division, the AIP's Statistical Research Center cross correlated and culled these data bases resulting in 2776 unique email addresses of US based working professionals. The survey received 1305 responses (51%) and generated 125 pages of single space answers to a number of open-ended questions. This talk will summarize the highlights of this first-ever demographic survey including findings extracted from the open-ended responses regarding barriers to career advancement which showed significant gender differences.

A randomized controlled trial of the Arctic Sun Temperature Management System versus conventional methods for preventing hypothermia during off-pump cardiac surgery.

PubMed

Grocott, Hilary P; Mathew, Joseph P; Carver, Elizabeth H; Phillips-Bute, Barbara; Landolfo, Kevin P; Newman, Mark F

2004-02-01

In this trial we compared the hypothermia avoidance abilities of the Arctic Sun Temperature Management System (a servo-regulated system that circulates temperature-controlled water through unique energy transfer pads adherent to the patient's body) with conventional temperature control methods. Patients undergoing off-pump coronary artery bypass (OPCAB) surgery were randomized to either the Arctic Sun System alone (AS group) or conventional methods (control group; increased room temperature, heated IV fluids, convective forced air warming system) for the prevention of hypothermia (defined by a temperature <36 degrees C). The AS group had nasopharyngeal temperature servo-regulated to a target of 36.8 degrees C. Temperature was recorded throughout the operative period and comparisons were made between groups for both the time and area under the curve (AUC) for a temperature <36 degrees C (AUC<36 degrees C). Twenty-nine patients (AS group = 14, control group = 15) were studied. The AS group had significantly less hypothermia than the control group, both for duration of time <36 degrees C (2.5 [0-22] min, median [interquartile range] AS group versus 118 [49-192] min, control group; P = 0.0008) as well as for AUC<36 degrees C (0.3 [0-2.2] degrees C x min, AS group versus 17.1 [3.6-173.4] degrees C x min, control group; P = 0.002). The Arctic Sun Temperature Management System significantly reduced intraoperative hypothermia during OPCAB surgery. Importantly, this was achieved in the absence of any other temperature modulating techniques, including the use of IV fluid warming or increases in the ambient operating room temperature. The Arctic Sun Temperature Management System was more effective than conventional methods in preventing hypothermia during off-pump coronary artery bypass graft surgery.

The NASA-Sponsored Study of Cataract in Astronauts (NASCA). Relationship of Exposure to Radiation in Space and the Risk of Cataract Incidence and Progression. Report 1: Recruitment and Methodology

NASA Technical Reports Server (NTRS)

Chylack, Leo T.; Peterson, Leif E.; Feiveson, Alan H.; Wear, Mary; Manuel, F. Keith

2007-01-01

The NASA Study of Cataract in Astronauts (NASCA) is a five-year, multi-centered, investigation of lens opacification in populations of U.S. astronauts, military pilots, and ground-based (nonaviator) comparison participants. For astronauts, the explanatory variable of most interest is radiation exposure during space flight, however to properly evaluate its effect, the secondary effects of age, nutrition, general health, solar ocular exposure, and other confounding variables encountered in non-space flight must also be considered. NASCA contains an initial baseline, cross-sectional objective assessment of the severity of cortical (C), nuclear (N), and posterior subcapsular (PSC) lens opacification, and annual follow-on assessments of severity and progression of these opacities in the population of astronauts and in participants sampled from populations of military pilots and ground-based exposure controls. From these data, NASCA will estimate the degree to which space radiation affects lens opacification for astronauts and how the overall risks of each cataract type for astronauts compared with those of the other exposure control groups after adjusting for differences in age and other explanatory variables.

Optical Communications Study for the Next Generation Space Telescope

NASA Technical Reports Server (NTRS)

Ceniceros, Juan M.

2000-01-01

The Next Generation Space Telescope (NGST), part of NASA's Origins program, is a follow on to the Hubble Space Telescope expected to provide timely new science along with answering fundamental questions. NGST is a large diameter, infrared optimized telescope with imaging and spectrographic detectors which will be used to help study the origin of galaxies. Due to the large data NGST will collect, Goddard Space Flight Center has considered the use of optical communications for data downlink. The Optical Communications Group at the Jet Propulsion Laboratory has performed a study on optical communications systems for NGST. The objective of the study was to evaluate the benefits gained through the use of optical communication technologies. Studies were performed for each of four proposed NGST orbits. The orbits considered were an elliptical orbit about the semi stable second Lagrangian point, a 1 by 3 AU elliptic orbit around the sun, a 1 AU drift orbit, and a 1 AU drift orbit at a 15 degree incline to the ecliptic plane. An appropriate optical communications system was determined for each orbit. Systems were evaluated in terms of mass, power consumption, size, and cost for each of the four proposed orbits.

The "Very Cool" James Webb Space Telescope!

NASA Technical Reports Server (NTRS)

Teague, Peter J. B.

2018-01-01

For over twenty years, scientists, engineers, technicians, and other personnel have been working on the next generation space telescope. As a partnership between NASA (National Aeronautics and Space Administration), CSA (Canadian Space Agency), and ESA (European Space Angency), the James Webb Space Telescope will complement the previous research performed by the Hubble by utilizing a larger primary mirror, which will also be optimized for infrared wavelengths. This combination will allow JWST to collect data and take images of light having traveled over 13.7 billion light years. This presentation will focus on the mission, as well as the contamination control challenges during the integration and testing in the NASA Goddard Spacecraft Systems Development and Integration Facility (SSDIF), one of the largest cleanrooms in the world. Additional information will be presented regarding space simulation testing down to a cool 20 degrees Kelvin [-424 degrees Fahrenheit] that will occur at Johnson Space Center in Houston, TX, and more testing and integration to happen at Northrop Grumman Corp., in Redondo Beach, CA. Launch of the JWST is currently scheduled for the spring of 2019 at Ariane Spaceport in French Guiana, South America.

A prospective, randomized evaluation of the effects of epidural needle rotation on the distribution of epidural block.

PubMed

Borghi, Battista; Agnoletti, Vanni; Ricci, Alessandro; van Oven, Hanna; Montone, Nicoletta; Casati, Andrea

2004-05-01

We evaluated the effects of turning the tip of the Tuohy needle 45 degrees toward the operative side before threading the epidural catheter (45 degrees -rotation group, n = 24) as compared to a conventional insertion technique with the tip of the Tuohy needle oriented at 90 degrees cephalad (control group, n = 24) on the distribution of 10 mL of 0.75% ropivacaine with 10 microg sufentanil in 48 patients undergoing total hip replacement. The catheter was introduced 3 to 4 cm beyond the tip of the Tuohy needle. A blinded observer recorded sensory and motor blocks on both sides, quality of analgesia, and volumes of local anesthetic used during the first 48 h of patient-controlled epidural analgesia. Readiness to surgery required 21 +/- 6 min in the control group and 17 +/- 7 min in the 45 degree-rotation group (P > 0.50). The maximum sensory level reached on the operative side was T10 (T10-7) in the control group and T9 (T10-6) in the 45 degree-rotation group (P > 0.50); whereas the maximum sensory level reached on the nonoperative side was T10 (T12-9) in the control group and L3 (L5-T12) in the 45 degree-rotation group (P = 0.0005). Complete motor blockade of the operative limb was achieved earlier in the 45 degree-rotation than in the control group, and motor block of the nonoperative side was more intense in patients in the control group. Two-segment regression of sensory level on the surgical side was similar in the two groups, but occurred earlier on the nonoperative side in the 45 degree-rotation group (94 +/- 70 min) than in the control group (178 +/- 40 min) (P = 0.0005). Postoperative analgesia was similar in the 2 groups, but the 45 degree-rotation group consumed less local anesthetic (242 +/- 35 mL) than the control group (297 +/- 60 mL) (P = 0.0005). We conclude that the rotation of the Tuohy introducer needle 45 degrees toward the operative side before threading the epidural catheter provides a preferential distribution of sensory and motor block toward the operative side, reducing the volume of local anesthetic solution required to maintain postoperative analgesia. Turning the Tuohy introducer needle 45 degrees toward the operative side before threading the epidural catheter is a simple maneuver that produces a preferential distribution of epidural anesthesia and analgesia toward the operative side, minimizing the volume of local anesthetic required to provide adequate pain relief after total hip arthroplasty.

Transition heating rates determined on a 0.006 scale space shuttle orbiter model (no. 50-0) in the NASA/LaRC Mach 8 variable density wind tunnel test (OH14)

NASA Technical Reports Server (NTRS)

Cummings, J.

1976-01-01

Data obtained from wind tunnel tests of an .006-scale space shuttle orbiter model in the 18 in. Variable Density Wind Tunnel are presented. The tests, denoted as OH14, were performed to determine transition heating rates using thin skin thermocouples located at various locations on the space shuttle orbiter. The model was tested at M = 8.0 for a range of Reynolds numbers per foot varying from 1.0 to 10.0 million with angles-of-attack from 20 to 35 degrees incremented by 5 degrees.

Matrix fatigue crack development in a notched continuous fiber SCS-6/Ti-15-3 composite

NASA Technical Reports Server (NTRS)

Hillberry, B. M.; Johnson, W. S.

1990-01-01

In this study the extensive matrix fatigue cracking that has been observed in notched SCS-6/Ti-15-3 composites is investigated. Away from the notch uniform spacing of the fatigue cracks develops. Closer to the notch, fiber-matrix debonding which occurs increases the crack spacing. Crack spacing and debond length determined from shear-lag cylinder models compare favorably with experimental observations. Scanning electron microscope (SEM) fractography showed that the principal fatigue crack initiation occurred around the zero degree fibers. Interface failure in the 90 degree plies does not lead to the development of the primary fatigue cracking.

Matrix fatigue crack development in a notched continuous fiber SCS-6/Ti-15-3 composite

NASA Technical Reports Server (NTRS)

Hillberry, B. M.; Johnson, W. S.

1990-01-01

In this study the extensive matrix fatigue cracking that has been observed in notched SCS-6/Ti-15-3 composites is investigated. Away from the notch a uniform spacing of the fatigue cracks develops. Closer to the notch, fiber-matrix debonding which occurs increases the crack spacing. Crack spacing and debond length determined from shear-lag cylinder models compare favorably with experimental observations. Scanning electron microscope (SEM) fractography showed that the principal fatigue crack initiation occurred around the zero degree fibers. Interface failure in the 90 degree plies does not lead to the development of the primary fatigue cracking.

Base reaction optimization of redundant manipulators for space applications

NASA Technical Reports Server (NTRS)

Chung, C. L.; Desa, S.; Desilva, C. W.

1988-01-01

One of the problems associated with redundant manipulators which were proposed for space applications is that the reactions transmitted to the base of the manipulator as a result of the motion of the manipulator will cause undesirable effects on the dynamic behavior of the supporting space structure. It is therefore necessary to minimize the magnitudes of the forces and moments transmitted to the base. It is shown that kinematic redundancy can be used to solve the dynamic problem of minimizing the magnitude of the base reactions. The methodology described is applied to a four degree-of-freedom spatial manipulator with one redundant degree-of-freedom.

The human role in space. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1984-01-01

The role and degree of direct involvement of humans required in future space missions were investigated. Criteria for allocating functional activities between humans and machines were established. The technology requirements, economics, and benefits of the human presence in space were investigated.

Emergent space-time via a geometric renormalization method

NASA Astrophysics Data System (ADS)

Rastgoo, Saeed; Requardt, Manfred

2016-12-01

We present a purely geometric renormalization scheme for metric spaces (including uncolored graphs), which consists of a coarse graining and a rescaling operation on such spaces. The coarse graining is based on the concept of quasi-isometry, which yields a sequence of discrete coarse grained spaces each having a continuum limit under the rescaling operation. We provide criteria under which such sequences do converge within a superspace of metric spaces, or may constitute the basin of attraction of a common continuum limit, which hopefully may represent our space-time continuum. We discuss some of the properties of these coarse grained spaces as well as their continuum limits, such as scale invariance and metric similarity, and show that different layers of space-time can carry different distance functions while being homeomorphic. Important tools in this analysis are the Gromov-Hausdorff distance functional for general metric spaces and the growth degree of graphs or networks. The whole construction is in the spirit of the Wilsonian renormalization group (RG). Furthermore, we introduce a physically relevant notion of dimension on the spaces of interest in our analysis, which, e.g., for regular lattices reduces to the ordinary lattice dimension. We show that this dimension is stable under the proposed coarse graining procedure as long as the latter is sufficiently local, i.e., quasi-isometric, and discuss the conditions under which this dimension is an integer. We comment on the possibility that the limit space may turn out to be fractal in case the dimension is noninteger. At the end of the paper we briefly mention the possibility that our network carries a translocal far order that leads to the concept of wormhole spaces and a scale dependent dimension if the coarse graining procedure is no longer local.

Modifying the baricity of local anesthetics for spinal anesthesia by temperature adjustment: model calculations.

PubMed

Heller, Axel R; Zimmermann, Katrin; Seele, Kristin; Rössel, Thomas; Koch, Thea; Litz, Rainer J

2006-08-01

Although local anesthetics (LAs) are hyperbaric at room temperature, density drops within minutes after administration into the subarachnoid space. LAs become hypobaric and therefore may cranially ascend during spinal anesthesia in an uncontrolled manner. The authors hypothesized that temperature and density of LA solutions have a nonlinear relation that may be described by a polynomial equation, and that conversion of this equation may provide the temperature at which individual LAs are isobaric. Density of cerebrospinal fluid was measured using a vibrating tube densitometer. Temperature-dependent density data were obtained from all LAs commonly used for spinal anesthesia, at least in triplicate at 5 degrees, 20 degrees, 30 degrees, and 37 degrees C. The hypothesis was tested by fitting the obtained data into polynomial mathematical models allowing calculations of substance-specific isobaric temperatures. Cerebrospinal fluid at 37 degrees C had a density of 1.000646 +/- 0.000086 g/ml. Three groups of local anesthetics with similar temperature (T, degrees C)-dependent density (rho) characteristics were identified: articaine and mepivacaine, rho1(T) = 1.008-5.36 E-06 T2 (heavy LAs, isobaric at body temperature); L-bupivacaine, rho2(T) = 1.007-5.46 E-06 T2 (intermediate LA, less hypobaric than saline); bupivacaine, ropivacaine, prilocaine, and lidocaine, rho3(T) = 1.0063-5.0 E-06 T (light LAs, more hypobaric than saline). Isobaric temperatures (degrees C) were as follows: 5 mg/ml bupivacaine, 35.1; 5 mg/ml L-bupivacaine, 37.0; 5 mg/ml ropivacaine, 35.1; 20 mg/ml articaine, 39.4. Sophisticated measurements and mathematic models now allow calculation of the ideal injection temperature of LAs and, thus, even better control of LA distribution within the cerebrospinal fluid. The given formulae allow the adaptation on subpopulations with varying cerebrospinal fluid density.

Nutrition: blood sample collection

NASA Image and Video Library

2007-03-20

ISS014-E-17550 (20 March 2007) --- Astronaut Michael E. Lopez-Alegria, Expedition 14 commander and NASA space station science officer, prepares to insert a test sample in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods.

Nutrition: blood sample collection

NASA Image and Video Library

2007-03-20

ISS014-E-17547 (20 March 2007) --- Astronaut Michael E. Lopez-Alegria, Expedition 14 commander and NASA space station science officer, prepares to insert a test sample in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods.

Crew Earth Observations (CEO) taken during Expedition Six

NASA Image and Video Library

2003-03-19

ISS006-E-40113 (19 March 2003) --- An oblique view of the South Island of New Zealand as photographed from the International Space Station by astronaut Donald R. Pettit, NASA ISS science officer and flight engineer for Expedition 6. Nadir point coordinates of the picture are 45.5 degrees south latitude and 166.5 degrees east longitude. The International Space Station was flying at an altitude of 211 nautical miles (391 kilometers) when the photo was taken.

KC-135 materials handling robotics

NASA Technical Reports Server (NTRS)

Workman, Gary L.

1991-01-01

Robot dynamics and control will become an important issue for implementing productive platforms in space. Robotic operations will become necessary for man-tended stations and for efficient performance of routine operations in a manned platform. The current constraints on the use of robotic devices in a microgravity environment appears to be due to an anticipated increase in acceleration levels due to manipulator motion and for safety concerns. The objective of this study will be to provide baseline data to meet that need. Most texts and papers dealing with the kinematics and dynamics of robots assume that the manipulator is composed of joints separated by rigid links. However, in recent years several groups have begun to study the dynamics of flexible manipulators, primarily for applying robots in space and for improving the efficiency and precision of robotic systems. Robotic systems which are being planned for implementation in space have a number of constraints to overcome. Additional concepts which have to be worked out in any robotic implementation for a space platform include teleoperation and degree of autonomous control. Some significant results in developing a robotic workcell for performing robotics research on the KC-135 aircraft in preperation for space-based robotics applications in the future were generated. In addition, it was shown that TREETOPS can be used to simulate the dynamics of robot manipulators for both space and ground-based applications.

The study of Thai stock market across the 2008 financial crisis

NASA Astrophysics Data System (ADS)

Kanjamapornkul, K.; Pinčák, Richard; Bartoš, Erik

2016-11-01

The cohomology theory for financial market can allow us to deform Kolmogorov space of time series data over time period with the explicit definition of eight market states in grand unified theory. The anti-de Sitter space induced from a coupling behavior field among traders in case of a financial market crash acts like gravitational field in financial market spacetime. Under this hybrid mathematical superstructure, we redefine a behavior matrix by using Pauli matrix and modified Wilson loop for time series data. We use it to detect the 2008 financial market crash by using a degree of cohomology group of sphere over tensor field in correlation matrix over all possible dominated stocks underlying Thai SET50 Index Futures. The empirical analysis of financial tensor network was performed with the help of empirical mode decomposition and intrinsic time scale decomposition of correlation matrix and the calculation of closeness centrality of planar graph.

Technical Report Writer’s Style Manual. Revision.

DTIC Science & Technology

1987-01-01

number and followed by a per!od, a zero , and a second period. Two blank spaces separate the heading number and the heading words. All letters in major...the word "degrees" as shown: 9 490 below zero e -15 °C e 45 to 65 OF 4. * 150 million degrees Fahrenheit o a 45-degree angle ,o * 450 north latitude 4...dm pound-force lb f degree Celcius °C pound-mass Ibm degree Farenheit OF pounds per second pps degrees per second deg/s pounds per square inch lb/in

What Are Space Exposure Histories Telling Us about CM Carbonaceous Chondrites?

NASA Technical Reports Server (NTRS)

Takenouchi, A.; Zolensky, Michael E.; Nishiizumi, K.; Caffee, M.; Velbel, M. A.; Ross, K.; Zolensky, P.; Le, L.; Imae, N.; Yamaguchi, A.;

Earth Observation taken by Expedition 33 crew

NASA Image and Video Library

2012-10-09

ISS033-E-011098 (9 Oct. 2012) --- One of the Expedition 33 crew members aboard the International Space Station took this night photo of Shenyang, China, located at 41.8 degrees north latitude and 123.43 degrees east longitude, alongside the smaller Sujiatun, China (center left). The orbital outpost was over a point centered at 40.4 degrees north latitude and 124.2 degrees east longitude when the photo was taken.

KSC-2012-6319

NASA Image and Video Library

2012-11-28

KSC-2012-6319 - CAPE CANAVERAL, Fla. - Paul Hintze is the researcher leading the trash-to-gas project at NASA's Kennedy Space Center in Florida. Hintze's group of six researchers at Kennedy and groups from NASA centers in Ohio, California and Texas wrote in a recent paper that the current methods of handling trash – either carrying it along on the round trip through space or gathering it into an expendable module and burning it up in Earth's atmosphere – are not suitable answers for missions that go beyond Earth orbit or even past the moon. Working in a laboratory at Kennedy, Hintze's team built an 80-pound device that looks like a three-foot-long metal pipe to test theories about incinerating a variety of trash ranging from used clothes to uneaten food. The reactor holds more than three quarts of material and burns at about 1,000 degrees F, about twice the maximum temperature of an average household oven. It's expected to take astronauts four hours to burn a day's worth of trash from a crew of four. During the course of a year in space – one half the length of time a mission to Mars is expected to take – trash processing for a crew of four would create about 2,200 pounds of methane fuel, enough to power a launch from the lunar surface, Hintze said. Photo credit: NASA/Dmitri Gerondidakis

KSC-2012-6320

NASA Image and Video Library

2012-11-28

KSC-2012-6320 – CAPE CANAVERAL, Fla. - Stephen Anthony works with an experimental reactor as part of the trash-to-gas project at NASA's Kennedy Space Center in Florida. A group of six researchers at Kennedy and groups from NASA centers in Ohio, California and Texas wrote in a recent paper that the current methods of handling trash – either carrying it along on the round trip through space or gathering it into an expendable module and burning it up in Earth's atmosphere – are not suitable answers for missions that go beyond Earth orbit or even past the moon. Working in a laboratory at Kennedy, Hintze's team built an 80-pound device that looks like a three-foot-long metal pipe to test theories about incinerating a variety of trash ranging from used clothes to uneaten food. The reactor holds more than three quarts of material and burns at about 1,000 degrees F, about twice the maximum temperature of an average household oven. It's expected to take astronauts four hours to burn a day's worth of trash from a crew of four. During the course of a year in space – one half the length of time a mission to Mars is expected to take – trash processing for a crew of four would create about 2,200 pounds of methane fuel, enough to power a launch from the lunar surface, Hintze said. Photo credit: NASA/Dmitri Gerondidakis

KSC-2012-6321

NASA Image and Video Library

2012-11-28

KSC-2012-6321 – CAPE CANAVERAL, Fla. – Anne Caraccio works with an experimental reactor as part of the trash-to-gas project at NASA's Kennedy Space Center in Florida. A group of six researchers at Kennedy and groups from NASA centers in Ohio, California and Texas wrote in a recent paper that the current methods of handling trash – either carrying it along on the round trip through space or gathering it into an expendable module and burning it up in Earth's atmosphere – are not suitable answers for missions that go beyond Earth orbit or even past the moon. Working in a laboratory at Kennedy, Hintze's team built an 80-pound device that looks like a three-foot-long metal pipe to test theories about incinerating a variety of trash ranging from used clothes to uneaten food. The reactor holds more than three quarts of material and burns at about 1,000 degrees F, about twice the maximum temperature of an average household oven. It's expected to take astronauts four hours to burn a day's worth of trash from a crew of four. During the course of a year in space – one half the length of time a mission to Mars is expected to take – trash processing for a crew of four would create about 2,200 pounds of methane fuel, enough to power a launch from the lunar surface, Hintze said. Photo credit: NASA/Dmitri Gerondidakis

gamma-Glutamyltranspeptidase from Escherichia coli K-12: formation and localization.

PubMed

Suzuki, H; Kumagai, H; Tochikura, T

1986-12-01

Escherichia coli cells showed maximum activity of gamma-glutamyltranspeptidase (EC 2.3.2.2) when they were grown at 20 degrees C, 14% of maximum activity at 37 degrees C, and none at 43 degrees C. The enzyme activity of intact cells grown at 20 degrees C was stably maintained after the temperature was changed to 45 degrees C. The activity increased during the exponential phase, and maximum activity was found at stationary phase. Its intracellular localization in the periplasmic space was confirmed.

Peak Power Markets for Satellite Solar Power

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

2002-01-01

This paper introduces first Indonesia, comprises 15,000 islands, has land area of two millions square kilometers. Extending from 95 to 141 degrees East longitude and from 6 degrees North to 11 degrees South latitude. Further the market of the Space Solar Power/SPS must be worldwide, including Indonesia. As we know, it can provide electricity anywhere in the world from the Earth's orbit, mostly Indonesia an equator country. We have to perform case studies of various countries to understand their benefits and disadvantages provided by the SSP, because each country has much different condition on energy from other countries. We are at the moment starting the international collaboration between Indonesia and Japan to carry out the case study for Indonesia. We understand that in Indonesia itself each province has much different micro-climate between one province compared to the other. In Japan, METI (Ministry of Economy, Trade and Industry) has already organized a committee to investigate the feasibility of Space Solar Power and to make a plan to launch a space demonstration of the SPS. While, Indonesia is quickly developing economy and increasing their energy demand. We are investigating the detailed energy conditions of Indonesia, the benefits and disadvantages of the Space Solar Power for Indonesia. Especially, we will perform the investigation on the receiving system for the Japanese pilot Space Power Satellite.

Motion deficit of the thumb in CMC joint arthritis.

PubMed

Gehrmann, Sebastian V; Tang, Jie; Li, Zong Ming; Goitz, Robert J; Windolf, Joachim; Kaufmann, Robert A

2010-09-01

Idiopathic osteoarthritis (OA) of the thumb carpometacarpal (CMC) joint is a common disabling disease that often causes pain and motion loss. The aims of this study were to characterize the multidimensional motion capability of the thumb CMC joint in a group with severe CMC OA and to compare it with a control group. We included 15 subjects with stage III/IV CMC OA according to the Eaton/Littler classification, and 15 control subjects. A motion analysis system using surface markers was employed to quantify the maximum boundary of the thumb circumduction envelope during repetitive thumb movements. We measured the area enclosed by the angular circumduction envelope and the ranges of motion (ROM) in multiple directions for the thumb CMC joint. Thumb osteoarthritis of the CMC joint stage III/IV resulted in a significantly smaller ROM in flexion/extension (45 degrees +/- 11 degrees for the CMC OA group, 59 degrees +/- 10 degrees for the controls), abduction-adduction (37 degrees +/- 6 degrees for the CMC OA group, 63 degrees +/- 13 degrees for the controls), and pronation-supination (49 degrees +/- 10 degrees for the CMC OA group, 62 degrees +/- 11 degrees for the controls) (p < .01). When analyzing the motion directions in flexion-extension and abduction-adduction separately, there was only a loss of extension and adduction (p < .01). Severe stages of thumb CMC OA cause an asymmetrical motion deficit with decreased ROM in extension and adduction, leading to decreased capability of counteropposition. Copyright 2010. Published by Elsevier Inc.

Rhesus monkeys (Macaca mulatta) map number onto space

PubMed Central

Drucker, Caroline B.; Brannon, Elizabeth M.

2014-01-01

Humans map number onto space. However, the origins of this association, and particularly the degree to which it depends upon cultural experience, are not fully understood. Here we provide the first demonstration of a number-space mapping in a non-human primate. We trained four adult male rhesus macaques (Macaca mulatta) to select the fourth position from the bottom of a five-element vertical array. Monkeys maintained a preference to choose the fourth position through changes in the appearance, location, and spacing of the vertical array. We next asked whether monkeys show a spatially-oriented number mapping by testing their responses to the same five-element stimulus array rotated ninety degrees into a horizontal line. In these horizontal probe trials, monkeys preferentially selected the fourth position from the left, but not the fourth position from the right. Our results indicate that rhesus macaques map number onto space, suggesting that the association between number and space in human cognition is not purely a result of cultural experience and instead has deep evolutionary roots. PMID:24762923

REU Site: CUNY/GISS CGCR - Increasing Diversity in Earth and Space Science and Space Technology Research

NASA Astrophysics Data System (ADS)

Johnson, L. P.; Marchese, P.; Carlson, B. E.; Howard, A. M.; Damas, M. C.; Boxe, C.; Sohl, L. E.; Cheung, T. D.; Zavala-Gutierrez, R.; Jiang, M.

2016-12-01

This presentation describes student projects and accomplishments of the NSF REU Site: The City University of New York / NASA Goddard Institute for Space Studies Center for Global Climate Research. These student experiences contribute to the preparation of a diverse workforce in the areas of ocean modeling, planetary atmospheres, atmospheric science, climate change, heliophysics and space technology. It is important to motivate students to continue their studies towards advanced degrees and pursue careers related to these fields of study. This is best accomplished by involving undergraduates in research. For the past three years, this REU Site has supported research for more than 35 students, approximately 60 percent from underrepresented minorities and 35 percent female. All the students have progressed towards their degrees and some have advanced to graduate study. This program is supported by NSF award AGS-1359293 REU Site: CUNY/GISS Center for Global Climate Research and the NASA New York State Space Grant Consortium and in collaboration with the NASA Goddard Institute for Space Studies (GISS).

Air-Conditioning for Electric Vehicles

NASA Technical Reports Server (NTRS)

Popinski, Z.

1984-01-01

Combination of ammonia-absorption refrigerator, roof-mounted solar collectors, and 200 degrees C service electric-vehicle motor provides evaporative space-heating/space cooling system for electric-powered and hybrid fuel/electric vehicles.

Application of Second-Moment Source Analysis to Three Problems in Earthquake Forecasting

NASA Astrophysics Data System (ADS)

Donovan, J.; Jordan, T. H.

2011-12-01

Though earthquake forecasting models have often represented seismic sources as space-time points (usually hypocenters), a more complete hazard analysis requires the consideration of finite-source effects, such as rupture extent, orientation, directivity, and stress drop. The most compact source representation that includes these effects is the finite moment tensor (FMT), which approximates the degree-two polynomial moments of the stress glut by its projection onto the seismic (degree-zero) moment tensor. This projection yields a scalar space-time source function whose degree-one moments define the centroid moment tensor (CMT) and whose degree-two moments define the FMT. We apply this finite-source parameterization to three forecasting problems. The first is the question of hypocenter bias: can we reject the null hypothesis that the conditional probability of hypocenter location is uniformly distributed over the rupture area? This hypothesis is currently used to specify rupture sets in the "extended" earthquake forecasts that drive simulation-based hazard models, such as CyberShake. Following McGuire et al. (2002), we test the hypothesis using the distribution of FMT directivity ratios calculated from a global data set of source slip inversions. The second is the question of source identification: given an observed FMT (and its errors), can we identify it with an FMT in the complete rupture set that represents an extended fault-based rupture forecast? Solving this problem will facilitate operational earthquake forecasting, which requires the rapid updating of earthquake triggering and clustering models. Our proposed method uses the second-order uncertainties as a norm on the FMT parameter space to identify the closest member of the hypothetical rupture set and to test whether this closest member is an adequate representation of the observed event. Finally, we address the aftershock excitation problem: given a mainshock, what is the spatial distribution of aftershock probabilities? The FMT representation allows us to generalize the models typically used for this purpose (e.g., marked point process models, such as ETAS), which will again be necessary in operational earthquake forecasting. To quantify aftershock probabilities, we compare mainshock FMTs with the first and second spatial moments of weighted aftershock hypocenters. We will describe applications of these results to the Uniform California Earthquake Rupture Forecast, version 3, which is now under development by the Working Group on California Earthquake Probabilities.

Microgravity-induced modifications of the vestibuloocular reflex in Xenopus laevis tadpoles are related to development and the occurrence of tail lordosis.

PubMed

Horn, Eberhard R

2006-08-01

During space flights, tadpoles of the clawed toad Xenopus laevis occasionally develop upward bended tails (tail lordosis). The tail lordosis disappears after re-entry to 1g within a couple of days. The mechanisms responsible for the induction of the tail lordosis are unknown; physical conditions such as weight de-loading or physiological factors such as decreased vestibular activity in microgravity might contribute. Microgravity (microg) also exerts significant effects on the roll-induced vestibuloocular reflex (rVOR). The rVOR was used to clarify whether tail lordosis is caused by physiological factors, by correlating the occurrence of microg-induced tail lordosis with the extent of microg-induced rVOR modifications. Post-flight recordings from three space flights (D-2 Spacelab mission, STS-55 in 1993; Shuttle-to-Mir mission SMM-06, STS-84 in 1997; French Soyuz taxi flight Andromède to ISS in 2001) were analyzed in these experiments. At onset of microgravity, tadpoles were at stages 25-28, 33-36 or 45. Parameters tested were rVOR gain (ratio between the angular eye movement and the lateral 30 degrees roll) and rVOR amplitude (maximal angular postural change of the eyes during a 360 degrees lateral roll). A ratio of 22-84% of tadpoles developed lordotic tails, depending on the space flight. The overall observation was that the rVOR of tadpoles with normal tails was either not affected by microgravity, or it was enhanced. In contrast, the rVOR of lordotic animals always revealed a depression. In particular, during post-flight days 1-11, tadpoles with lordotic tails from all three groups (25-28, 33-36 and 45) showed a lower rVOR gain and amplitude than the 1g-controls. The rVOR gain and amplitude of tadpoles from the groups 25-28 and 33-36 that developed normal tails was not affected by microgravity while the rVOR of microg-tadpoles from the stage-45 group with normal tails revealed a significant rVOR augmentation. (1) the vestibular system of tadpoles with lordotic tails is developmentally retarded by microgravity; (2) after a critical status of vestibular maturation obtained during the appearance of first swimming, microgravity activates an adaptation mechanism that causes a sensitization of the vestibular system.

Antiferromagnetic coupling in a six-coordinate high spin cobalt(II)-semiquinonato complex.

PubMed

Caneschi, Andrea; Dei, Andrea; Gatteschi, Dante; Tangoulis, Vassilis

2002-07-01

The 3,5-di-tert-butyl-catecholato and 9,10-phenanthrenecatecholato adducts of the cobalt-tetraazamacrocycle complex Co(Me(4)cyclam)(2+) (Me(4)cyclam = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) were synthesized and oxidized. The oxidation reaction products were isolated in the solid state as hexafluorophosphate derivatives. Both these complexes can be formulated as 1:1 cobalt(II)-semiquinonato complexes, that is, Co(Me(4)cyclam)(DBSQ)PF(6) (1) and Co(Me(4)cyclam)(PhSQ)PF(6) (2), in the temperature range 4-300 K, in striking contrast with the charge distribution found in similar adducts formed by related tetraazamacrocycles. The synthesis strategy and the structural, spectroscopic, and magnetic properties are reported and discussed. The crystallographic data for 2 are as follows: monoclinic, space group P2(1)/a, nomicron. 14, a = 14.087(4) A, b = 15.873(4) A, c = 14.263 (7) A, alpha = 89.91(3) degrees, beta = 107.34(2) degrees, gamma = 90.08(2) degrees, Z = 4. Both these complexes are characterized by triplet electronic ground states arising from the antiferromagnetic coupling between the high-spin d(7) metal ion and the radical ligand.

A Novel Pentadentate Coordination Mode for the Carbonato Bridge: Synthesis, Crystal Structure, and Magnetic Behavior of (&mgr;(3)-CO(3))[Ni(3)(Medpt)(3)(NCS)(4)], a New Trinuclear Nickel(II) Carbonato-Bridged Complex with Strong Antiferromagnetic Coupling.

PubMed

Escuer, Albert; Vicente, Ramon; Kumar, Sujit B.; Solans, Xavier; Font-Bardía, Mercé; Caneschi, Andrea

1996-05-22

The trinuclear complex (&mgr;(3)-CO(3))[Ni(3)(Medpt)(3)(NCS)(4)] was obtained by reaction of basic solutions of nickel(II), Medpt (bis(3aminopropyl)methylamine) and thiocyanate ligand with atmospheric CO(2) or by simple reaction with carbonate anion. (&mgr;(3)-CO(3))[Ni(3)(Medpt)(3)(NCS)(4)] crystallizes in the triclinic system, space group P&onemacr;, with a = 12.107(5) Å, b = 12.535(7) Å, c = 16.169(9) Å, alpha = 102.69(5) degrees, beta = 92.91(5) degrees, gamma = 118.01(4) degrees, Z = 2, and R = 0.043. The three nickel atoms are asymmetrically bridged by one pentadentate carbonato ligand, which shows a novel coordination mode. The (&mgr;(3)-CO(3))[Ni(3)(Medpt)(3)(NCS)(4)] compound shows a very strong antiferromagnetic coupling. Fit as irregular triangular arrangement gave J(1) = -88.4, J(2) = -57.7, and J(3) = -9.6 cm(-)(1), which is the strongest AF coupling observed to date for Ni(3) compounds. The magnetic behavior of the carbonato bridge is discussed.

Navy Activity-Level Energy Systems Planning Procedure (A-LESP) Users Manual.

DTIC Science & Technology

1986-01-01

1-in. stucco, air space 1.95 0.512 0.5-in. gypsum or plasterboard 0.56 1.78 Insulating drapes 1.72 0.58 ROOFS 2-in. insulation, 1-in. wood, air space...3 Annual Dry Bulb Degree Hours Above 780 F ............................ 267 -’ Table SDI Energy Conversion Units...A-LESP SURVEY DATE 5/83 Langleys 400 OPT. FEASIBILITY (YES/NO) Yes Dry bulb degree hours greater NES 180 MBtu/yr than 780 F 10,000 SIR 1.81_ Cooling

STS-61A earth observations

NASA Image and Video Library

1985-11-02

61A-52-049 (30 Oct-6 Nov 1985) --- A 70mm image of the Strait of Dover area showing southeast England as photographed from the Earth-orbiting Space Shuttle Challenger by the astronaut crew members of the STS-61A mission. Center point coordinates in the handheld Hasselblad scene are 45.5 degrees north latitude and 0.5 degrees east longitude. Five NASA astronauts were joined by three European scientists for the week-long space flight, marking the largest roster on any Shuttle mission to date.

Center Planning and Development Student Engineer at KSC

NASA Technical Reports Server (NTRS)

Jenkins, Kenneth T., Jr.

2015-01-01

This summer I was the Student Trainee (Engineering) Pathways Intern (co-op) at the Kennedy Space Center (KSC) in the Center Planning & Development (CPD) Directorate. CPD works with commercial companies who are interested in using KSC's unique capabilities for spaceflight, spacecraft processing, ground systems and Research & Development (R&D) projects that fall in line with NASA's Mission and Vision. CPD is divided into three (3) groups: (1) AD-A, which works on the Master Planning for the center, (2) AD-B (where I am), which works on project control, management and integration, and (3) AD-C, which works on partnership development. CPD's main goal is to make KSC the world's preeminent multi-user spaceport and maintain the center as a leader in space exploration. CPD is a very diverse group of employees having a wide knowledge of not only the Space Shuttle, but also Expendable Launch Vehicles (ELV). The director of CPD, Scott Colloredo, is on the advisory board for Commercial Space Operations (CSO) and has a degree from ERAU. I worked on a number of different tasks for AD-B, as well as CPD, that includes, but not limited to: reviewing and reissuing engineering documents, weekly notes for CPD and senior management, engineering familiarizations with facilities at KSC, leading a tour for the Embry-Riddle Aeronautical University Career Services office, and working on actual agreements/proposals that will be used in the partnership process with multiple partners, along with other projects. Most of the work I have done is sensitive information and cannot be disclosed.

Spaced sessions of avoidance extinction reduce spontaneous recovery and promote infralimbic cortex activation.

PubMed

Tapias-Espinosa, Carles; Kádár, Elisabet; Segura-Torres, Pilar

2018-01-15

Extinction-based therapies (EBT) are the psychological treatments of choice for certain anxiety disorders, such as post-traumatic stress disorder. However, some patients relapse and suffer spontaneous recovery (SR) of anxiety symptoms and persistence of avoidance behaviour, which underlines the need for improving EBT. In rats, recent evidence has highlighted the relevance of the temporal distribution of extinction sessions in reducing SR of auditory fear conditioning, although it has seldom been studied in procedures involving proactive avoidance responses, such as two-way active avoidance conditioning (TWAA). We examined whether the temporal distribution of two extinction sessions separated by 24h or 7days (contiguous versus spaced extinction paradigms, respectively), influences SR after 28days of a TWAA task. c-Fos expression, as a marker of neuronal activation, was also measured by immunohistochemistry 90min after the SR test in the amygdala and the medial prefrontal cortex. The temporal distribution of extinction sessions did not affect the degree of extinction learning. However, only the rats that underwent the 7-day spaced extinction paradigm maintained the level of extinction in the long term, showing no SR in TWAA. This behavioural finding was consistent with a greater number of c-Fos-labelled neurons in the infralimbic cortex in the 7-day group, and in the Lateral and Central nuclei of the amygdala in the 24-hour group. These findings show that a time-spaced extinction paradigm reduces the spontaneous recovery of active avoidance behaviour, and that this behavioural advantage appears to be related to the activation of the infralimbic cortex. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of resin bonded bridgework on quality of life of patients with hypodontia.

PubMed

Anweigi, Lamyia; Finbarr Allen, P; Ziada, Hassan

2013-08-01

To determine the impact of hypodontia on the quality of life of adolescent and young adult patients, and, to assess the impact of restoring tooth spaces with resin bonded bridgework on quality of life of patients with hypodontia. In a prospective study, 82 patients with a confirmed diagnosis of hypodontia participated. The primary outcome was oral health related quality of life (OHRQoL) and this was measured using the OHIP-49 prior to treatment. The pre-treatment sample was then divided into two groups: the test group (n=40 patients) who had completed orthodontic treatment and had tooth spaces restored with resin bonded bridgework, and, a control group (n=42 patients) who were still in the process of orthodontic treatment. All patients completed a follow-up OHIP-49, and between and within group comparisons made. The pre-treatment sample included 43 females and 39 males, age ranged from 16 to 34 years (median age 19). Forty-three patients had more than 4 congenitally missing teeth and thirty-nine had ≤ 4 congenitally missing teeth. There were no differences between the groups prior to treatment. For the test group, there was a significant improvement in median OHIP summary scores (p<0.001) after treatment. OHIP scores deteriorated to a significant degree for control subjects (p=0.002). The effect sizes for the pre-post treatment change in both groups were moderate to large. Hypodontia has a significant impact on oral health related quality of life. Provision of resin bonded bridges has a positive impact on oral health related quality of life of patients with hypodontia. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dietary habits of colorectal neoplasia patients in comparison to their first-degree relatives.

PubMed

Kajzrlikova, Ivana Mikoviny; Vitek, Petr; Chalupa, Josef; Dite, Petr

2014-05-07

To compare the dietary habits between colorectal neoplasia patients, their first-degree relatives, and unrelated controls. From July 2008 to April 2011, we collected epidemiological data relevant to colorectal cancer from patients with colorectal neoplasias, their first-degree relatives, and also from a control group consisting of people referred for colonoscopy with a negative family history of colorectal cancer and without evidence of neoplasia after colonoscopic examination. The first-degree relatives were divided into two groups following the colonoscopic examination: (1) patients with neoplasia or (2) patients without neoplasia. Dietary habits of all groups were compared. A χ (2) test was used to assess the association between two dichotomous categorical variables. The study groups consisted of 242 patients with colorectal neoplasias (143 men, 99 women; mean age: 64 ± 12 years) and 160 first-degree relatives (66 men, 94 women; mean age: 48 ± 11 years). Fifty-five of the first-degree relatives were found to have a neoplastic lesion upon colonoscopy, while the remaining 105 were without neoplasia. The control group contained 123 individuals with a negative family history for neoplastic lesions (66 men, 57 women; mean age: 54 ± 12 years). Two hypotheses were tested. In the first, the dietary habits of first-degree relatives with neoplasia were more similar to those of patients with neoplasia, while the dietary habits of first-degree relatives without neoplasia were similar to those of the control group. In the second, no sex-related differences in dietary habits were expected between the particular groups. Indeed, no significant differences were observed in the dietary habits between the groups of patients, controls and first-degree relatives with/without neoplastic lesions. Nevertheless, statistically significant sex-related differences were observed in all groups, wherein women had healthier dietary habits than men. In all groups examined, women had healthier dietary habits than men. Modification of screening guidelines according to sex may improve the efficiency of screening programs.

Catalytic two-stage coal liquefaction process having improved nitrogen removal

DOEpatents

Comolli, Alfred G.

1991-01-01

A process for catalytic multi-stage hydrogenation and liquefaction of coal to produce high yields of low-boiling hydrocarbon liquids containing low concentrations of nitogen compounds. First stage catalytic reaction conditions are 700.degree.-800.degree. F. temperature, 1500-3500 psig hydrogen partial pressure, with the space velocity maintained in a critical range of 10-40 lb coal/hr ft.sup.3 catalyst settled volume. The first stage catalyst has 0.3-1.2 cc/gm total pore volume with at least 25% of the pore volume in pores having diameters of 200-2000 Angstroms. Second stage reaction conditions are 760.degree.-870.degree. F. temperature with space velocity exceeding that in the first stage reactor, so as to achieve increased hydrogenation yield of low-boiling hydrocarbon liquid products having at least 75% removal of nitrogen compounds from the coal-derived liquid products.

Results of investigations on a 0.010-scale 140A/B configuration space shuttle vehicle orbiter model 72-0 in the NASA/Langley Research Center continuous flow hypersonic tunnel (OA90)

NASA Technical Reports Server (NTRS)

Hawthorne, P. J.

1975-01-01

Data are documented which were obtained during wind tunnel tests. The test was conducted beginning 4 March and ending 6 March 1974 for a total of 24 occupancy hours. all test runs were conducted at a Mach number of 10.3 and at Reynolds numbers of 0.65, 1.0 and 1.33 million per foot. Only the complete 140A/B was tested with various elevon, speedbrake, and bodyflap settings at angles of attack from 12 to 37 degrees at 0 and -5 degrees of beta, and from 0 to -9 degrees of beta at 20 and 30 degrees angle of attack. The purpose was to obtain hypersonic longitudinal and lateral-directional stability and control characteristics of the updated space shuttle vehicle configuration.

Transonic wind tunnel tests of A.015 scale space shuttle orbiter model, volume 1

NASA Technical Reports Server (NTRS)

Struzynski, N. A.

1975-01-01

Transonic wind tunnel tests were run on a 0.015 scale model of the Space Shuttle Orbiter Vehicle in an eight-foot tunnel during August 1975. The purpose of the program was to obtain basic shuttle aerodynamic data through a full range of elevon and aileron deflections, verification of data obtained at other facilities, and effects of Reynolds numbers. The first part of a discussion of test procedures and results in both tabular and graphical form were presented. Tests were performed at Mach numbers from 0.35 to 1.20, and at Reynolds numbers for 3.5 million to 8.2 million per foot. The angle of attack was varied from -1 to +20 degrees at sideslip angles of -2, 0, +2 degrees. Sideslip was varied from -6 to +8 degrees at constant angles of attack from 0 to +20 degrees. Various aileron and ailevon settings were tested for various angles of attack.

Transonic wind tunnel tests of a .015 scale space shuttle orbiter model, volume 2

NASA Technical Reports Server (NTRS)

Struzynski, N. A.

1975-01-01

Transonic wind tunnel tests were run on a 0.015 scale model of the Space Shuttle Orbiter Vehicle in an eight-foot tunnel during August 1975. The purpose of the program was to obtain basic shuttle aerodynamic data through a full range of elevon and aileron deflections, verification of data obtained at other facilities, and effects of Reynolds numbers. The second part of a discussion of test procedures and results in both tabular and graphical form were presented. Tests were performed at Mach numbers from 0.35 to 1.20, and at Reynolds numbers from 3.5 million to 8.2 million per foot. The angle of attack was varied from -2 to +20 degrees at sideslip angles of -2, 0, +2 degrees. Sideslip was varied from -6 to +8 degrees at constant angles of attack from 0 to +20 degrees. Various aileron and ailevon settings were tested for various angles of attack.

Dominant effect of increasing forest biomass on evapotranspiration: interpretations of movement in Budyko space

NASA Astrophysics Data System (ADS)

Jaramillo, Fernando; Cory, Neil; Arheimer, Berit; Laudon, Hjalmar; van der Velde, Ype; Hasper, Thomas B.; Teutschbein, Claudia; Uddling, Johan

2018-01-01

During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s) of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961-2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60 % of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large-scale evapotranspiration changes in Swedish forests.

Arrival of Soyuz Spacecraft (TMA-07M)

NASA Image and Video Library

2012-12-21

ISS034-E-009924 (21 Dec. 2012) --- As the International Space Station and Soyuz TMA-07M spacecraft were making their relative approaches on Dec. 21, one of the Expedition 34 crew members on the orbital outpost captured this photo of the Soyuz backdropped by the Sahara Desert. Inside the arriving spacecraft were astronaut Chris Hadfield of the Canadian Space Agency, cosmonaut Roman Romanenko of Russia's Federal Space Agency and NASA astronaut Tom Marshburn. The image center is at 31.7 degrees north latitude and 2.0 degrees east longitude, on the south side of the Atlas Mountains and on the northern margin of a huge dune field known as Grand Erg Occidental, located in north central Algeria.

Arrival of Soyuz Spacecraft (TMA-07M)

NASA Image and Video Library

2012-12-21

ISS034-E-009926 (21 Dec. 2012) --- As the International Space Station and Soyuz TMA-07M spacecraft were making their relative approaches on Dec. 21, one of the Expedition 34 crew members on the orbital outpost captured this photo of the Soyuz over the Sahara Desert. The image center is at 31.7 degrees north latitude and 2.0 degrees east longitude, on the south side of the Atlas Mountains and on the northern margin of a huge dune field known as Grand Erg Occidental, located in north central Algeria. Inside the arriving spacecraft were astronaut Chris Hadfield of the Canadian Space Agency, cosmonaut Roman Romanenko of Russia's Federal Space Agency and NASA astronaut Tom Marshburn.

A growing social network model in geographical space

NASA Astrophysics Data System (ADS)

Antonioni, Alberto; Tomassini, Marco

2017-09-01

In this work we propose a new model for the generation of social networks that includes their often ignored spatial aspects. The model is a growing one and links are created either taking space into account, or disregarding space and only considering the degree of target nodes. These two effects can be mixed linearly in arbitrary proportions through a parameter. We numerically show that for a given range of the combination parameter, and for given mean degree, the generated network class shares many important statistical features with those observed in actual social networks, including the spatial dependence of connections. Moreover, we show that the model provides a good qualitative fit to some measured social networks.

Determination of Acreage Thermal Protection Foam Loss From Ice and Foam Impacts

NASA Technical Reports Server (NTRS)

Carney, Kelly S.; Lawrence, Charles

2015-01-01

A parametric study was conducted to establish Thermal Protection System (TPS) loss from foam and ice impact conditions similar to what might occur on the Space Launch System. This study was based upon the large amount of testing and analysis that was conducted with both ice and foam debris impacts on TPS acreage foam for the Space Shuttle Project External Tank. Test verified material models and modeling techniques that resulted from Space Shuttle related testing were utilized for this parametric study. Parameters varied include projectile mass, impact velocity and impact angle (5 degree and 10 degree impacts). The amount of TPS acreage foam loss as a result of the various impact conditions is presented.

Group theoretical methods and wavelet theory: coorbit theory and applications

NASA Astrophysics Data System (ADS)

Feichtinger, Hans G.

2013-05-01

Before the invention of orthogonal wavelet systems by Yves Meyer1 in 1986 Gabor expansions (viewed as discretized inversion of the Short-Time Fourier Transform2 using the overlap and add OLA) and (what is now perceived as) wavelet expansions have been treated more or less at an equal footing. The famous paper on painless expansions by Daubechies, Grossman and Meyer3 is a good example for this situation. The description of atomic decompositions for functions in modulation spaces4 (including the classical Sobolev spaces) given by the author5 was directly modeled according to the corresponding atomic characterizations by Frazier and Jawerth,6, 7 more or less with the idea of replacing the dyadic partitions of unity of the Fourier transform side by uniform partitions of unity (so-called BUPU's, first named as such in the early work on Wiener-type spaces by the author in 19808). Watching the literature in the subsequent two decades one can observe that the interest in wavelets "took over", because it became possible to construct orthonormal wavelet systems with compact support and of any given degree of smoothness,9 while in contrast the Balian-Low theorem is prohibiting the existence of corresponding Gabor orthonormal bases, even in the multi-dimensional case and for general symplectic lattices.10 It is an interesting historical fact that* his construction of band-limited orthonormal wavelets (the Meyer wavelet, see11) grew out of an attempt to prove the impossibility of the existence of such systems, and the final insight was that it was not impossible to have such systems, and in fact quite a variety of orthonormal wavelet system can be constructed as we know by now. Meanwhile it is established wisdom that wavelet theory and time-frequency analysis are two different ways of decomposing signals in orthogonal resp. non-orthogonal ways. The unifying theory, covering both cases, distilling from these two situations the common group theoretical background lead to the theory of coorbit spaces,12, 13 established by the author jointly with K. Gröchenig. Starting from an integrable and irreducible representation of some locally compact group (such as the "ax+b"-group or the Heisenberg group) one can derive families of Banach spaces having natural atomic characterizations, or alternatively a continuous transform associated to it. So at the end function spaces of locally compact groups come into play, and their generic properties help to explain why and how it is possible to obtain (nonorthogonal) decompositions. While unification of these two groups was one important aspect of the approach given in the late 80th, it was also clear that this approach allows to formulate and exploit the analogy to Banach spaces of analytic functions invariant under the Moebius group have been at the heart in this context. Recent years have seen further new instances and generalizations. Among them shearlets or the Blaschke product should be mentioned here, and the increased interest in the connections between wavelet theory and complex analysis. The talk will try to summarize a few of the general principles which can be derived from the general theory, but also highlight the difference between the different groups and signal expansions arising from corresponding group representations. There is still a lot more to be done, also from the point of view of applications and the numerical realization of such non-orthogonal expansions.

A high precision micropositioner with five degrees of freedom based on an electromagnetic driving principle

NASA Astrophysics Data System (ADS)

Wang, Wanjun; He, Tian

1996-01-01

A five degrees of freedom high precision micropositioner based on spring suspension and electromagnetic driving has been designed, constructed, and tested. The device consists of two parts: a moving part and a stationary part. The moving part, named as ``motor'', is formed with a rigid frame and three groups of coils fixed on it. The stationary part of the device, called ``stator'', includes a chassis and twelve U-shaped magnetic ``shoes''. The motor is attached to the stator with flat springs whose linear suspension allows it to move in all dimensions except the rotation around z axis. The coils have been laid out in such a way that fractions of them pass through the air gaps between the facing magnets in the magnetic shoes. When electrical currents are supplied to the coils, the resulting Lorenz forces drive the motor to move in the five degrees of freedom allowed by the spring suspension. Since the system is inherently stable and there is no mechanical friction, the open-loop resolutions of the device are found to be limited only by that of the 12-bit D/A board used. A closed-loop translation resolution of 0.3 μm has been achieved over a working space of 180 μm by 180 μm by 680 μm. A closed-loop rotation resolution of 2.73×10-6 rad has been achieved over a working space of 1.38×10-3 rad. Potentially the device can be used for high precision microprobing and testing, cellular biology, microsurgery, and testing of micromechanical devices in the fast developing MEMS area.

Poisson-Lie duals of the η deformed symmetric space sigma model

NASA Astrophysics Data System (ADS)

Hoare, Ben; Seibold, Fiona K.

2017-11-01

Poisson-Lie dualising the η deformation of the G/H symmetric space sigma model with respect to the simple Lie group G is conjectured to give an analytic continuation of the associated λ deformed model. In this paper we investigate when the η deformed model can be dualised with respect to a subgroup G0 of G. Starting from the first-order action on the complexified group and integrating out the degrees of freedom associated to different subalgebras, we find it is possible to dualise when G0 is associated to a sub-Dynkin diagram. Additional U1 factors built from the remaining Cartan generators can also be included. The resulting construction unifies both the Poisson-Lie dual with respect to G and the complete abelian dual of the η deformation in a single framework, with the integrated algebras unimodular in both cases. We speculate that extending these results to the path integral formalism may provide an explanation for why the η deformed AdS5 × S5 superstring is not one-loop Weyl invariant, that is the couplings do not solve the equations of type IIB supergravity, yet its complete abelian dual and the λ deformed model are.

Effect of Nd Doping on Dielectric and Impedance Properties of PZT Nanoceramics

NASA Astrophysics Data System (ADS)

Kour, P.; Pradhan, S. K.; Kumar, Pawan; Sinha, S. K.; Kar, Manoranjan

2018-02-01

Neodymium-doped lead zirconate tianate, i.e. Pb1-x Nd x Zr0.52Ti0.48O3 (PNZT) ceramics, with x = 0-10 mol.% has been prepared by the sol-gel process. X-ray diffraction pattern at room temperature shows the pyrochlore free phase for all samples. The structural analysis suggests the coexistence of both rhombohedral (R3m space group) and tetragonal (P4 mm space group) crystal symmetries. Scanning electron micrographs of the samples show uniform distribution of grain and grain boundaries. Dielectric constant increases with the increase in neodymium concentration in the crystal lattice. Degree of diffuse phase transition increases with the increase in Nd3+ concentration in the sample. Nd3+ incorporation into the lead zirconatetitanate (PZT) lattice enhances the spreading factor. Interaction between neighbouring dipoles decreases with the increase of Nd3+ in PZT lattice. The conduction mechanism of the sample can be attributed to the overlapping large polar tunnelling. Second-order dielectric phase transition has been observed at the Curie temperature. The electrical properties of the sample can be explained by considering grain and grain boundaries contributions. All the samples show the poly-dispersive non-Debye type relaxation.

A randomized controlled comparison of stretching procedures for posterior shoulder tightness.

PubMed

McClure, Philip; Balaicuis, Jenna; Heiland, David; Broersma, Mary Ellen; Thorndike, Cheryl K; Wood, April

2007-03-01

Randomized controlled trial, To compare changes in shoulder internal rotation range of motion (ROM), for 2 stretching exercises, the "cross-body stretch" and the "sleeper stretch," in individuals with posterior shoulder tightness. Recently, some authors have expressed the belief that the sleeper stretch is better than the cross-body stretch to address glenohumeral posterior tightness because the scapula is stabilized. Fifty-four asymptomatic subjects (20 males, 34 females) participated in the study. The control group (n=24) consisted of subjects with a between-shoulder difference in internal rotation ROM of less than 10 degrees, whereas those subjects with more than a 10 degrees difference were randomly assigned to 1 of 2 intervention groups, the sleeper stretch group (n=15) or the cross-body stretch group (n=15). Shoulder internal rotation ROM, with the arm abducted to 90 degrees and scapula motion prevented, was measured before and after a 4-week intervention period. Subjects in the control group were asked not to engage in any new stretching activities, while subjects in the 2 stretching groups were asked to perform stretching exercises on the more limited side only, once daily for 5 repetitions, holding each stretch for 30 seconds. The improvements in internal rotation ROM for the subjects in the cross-body stretch group (mean +/- SD, 20.0 degrees +/- 12.9 degrees) were significantly greater than for the subjects in the control group (5.9 degrees +/- 9.4 degrees, P = .009). The gains in the sleeper stretch group (12.4 degrees +/- 10.4 degrees) were not significant compared to those of the control group (P = .586) and those of the cross-body stretch group (P = .148). The cross-body stretch in individuals with limited shoulder internal rotation ROM appears to be more effective than no stretching in controls without internal rotation asymmetry to improve shoulder internal rotation ROM. While the improvement in internal rotation from the cross-body stretch was greater than for the sleeper stretch and of a magnitude that could be clinically significant, the small sample size likely precluded statistical significance between groups.

Application Number 3: Using Tethers for Attitude Control

NASA Technical Reports Server (NTRS)

Muller, R. M.

1985-01-01

Past application of the gravity gradient concept to satellite attitude control produced attitude stabilities of from 1 to 10 degrees. The satellite members were rigigly interconnected and any motion in one part of the satellite would cause motion in all members. This experience has restricted gravity gradient stabilization to applications that need attitude stability no better than 1 degree. A gravity gradient technique that combines the flexible tether with an active control that will allow control stability much better than 1 degree is proposed. This could give gravity gradient stabilization much broader application. In fact, for a large structure like a space station, it may become the preferred method. Two possible ways of demonstrating the techniques using the Tethered Satellite System (TSS) tether to control the attitude of the shuttle are proposed. Then a possible space station tether configuration is shown that could be used to control the initial station. It is then shown how the technique can be extended to the control of space stations of virtually any size.

In vitro study of heat production during power reduction of equine mandibular teeth.

PubMed

Allen, Martin L; Baker, Gordon J; Freeman, David E; Holmes, Kenneth R; Marretta, Sandra Manfra; Scoggins, R Dean; Constable, Peter

2004-04-01

To measure the amount of heat generated during 3 methods of equine dental reduction with power instruments. In vitro study. 30 premolar and molar teeth removed from mandibles of 8 equine heads collected at an abbatoir. 38-gauge copper-constantan thermocouples were inserted into the lingual side of each tooth 15 mm (proximal) and 25 mm (distal) from the occlusal surface, at a depth of 5 mm, which placed the tip close to the pulp chamber. Group-NC1 (n = 10) teeth were ground for 1 minute without coolant, group-NC2 (10) teeth were ground for 2 minutes without coolant, and group-C2 (10) teeth were ground for 2 minutes with water for coolant. Mean temperature increase was 1.2 degrees C at the distal thermocouple and 6.6 degrees C at the proximal thermocouple for group-NC1 teeth, 4.1 degrees C at the distal thermocouple and 24.3 degrees C at the proximal thermocouple for group-NC2 teeth, and 0.8 degrees C at the distal thermocouple and -0.1 degrees C at the proximal thermocouple for group-C2 teeth. In general, an increase of 5 degrees C in human teeth is considered the maximum increase before there is permanent damage to tooth pulp. In group-NC2 teeth, temperature increased above this limit by several degrees, whereas in group-C2 teeth, there was little or no temperature increase. Our results suggest that major reduction of equine teeth by use of power instruments causes thermal changes that may cause irreversible pulp damage unless water cooling is used.

Outcomes of torsional microcoaxial phacoemulsification performed by 12-degree and 22-degree bent tips.

PubMed

Helvacioglu, Firat; Yeter, Celal; Tunc, Zeki; Sencan, Sadik

2013-08-01

To compare the safety and efficacy of Ozil Intelligent Phaco torsional microcoaxial phacoemulsification surgeries performed with 12-degree and 22-degree bent tips using the Infiniti Vision System. Maltepe University School of Medicine Department of Ophthalmology, Istanbul, Turkey. Comparative case series. Eyes were assigned to 2.2 mm microcoaxial phacoemulsification using the torsional mode with a 22-degree bent tip (Group 1) or a 12-degree bent tip (Group 2). The primary outcome measures were ultrasound time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound (US) amplitudes, mean surgical time, mean volume of balanced salt solution used, and surgical complications. Both groups included 45 eyes. The mean UST, CDE, longitudinal US amplitude, and torsional US amplitude were 65 seconds ± 27.23 (SD), 11.53 ± 6.99, 0.22 ± 0.26, and 42.86 ± 15.64, respectively, in Group 1 and 84 ± 45.04 seconds, 16.68 ± 10.66, 0.48 ± 0.68, and 46.27 ± 14.74, respectively, in Group 2. The mean UST, CDE, and longitudinal amplitudes were significantly lower in Group 1 (P=.003, P=.008, and P=.022, respectively). The mean volume of balanced salt solution was 73.33 ± 28.58 cc in Group 1 and 82.08 ± 26.21 cc in Group 2 (P=.134). Torsional phacoemulsification performed with 22-degree bent tips provided more effective lens removal than 12-degree bent tips, with a lower UST and CDE. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

[Application and effect of auricular acupoint pressing for analgesia in perioperative period of total knee joint replacement].

PubMed

Tong, Pei-Jian; Wang, Hai-Dong; Ma, Zhen-Chuan

2010-09-01

To observe the effect of auricular acupoint pressing (AAP) for analgesia during perioperative period of total knee joint replacement. Sixty patients with osteoarthritis of ASA grade I - III scheduled to receive unilateral total knee joint replacement were equally randomized into the AAP group and the control group, 30 in each group. The general anesthesia on all patients was implemented by physicians of an identical group through endotracheal intubation. To the patients in the AAP group, AAP with Vaccaria seed was applied before operation, and the local analgesia on affected limb with acupoint pasting was used after operation. Besides, administering of celecoxib 400 mg on the day before operation, and celecoxib 200 mg twice daily post-operation was given to all patients. When the visual analogue scales (VAS) reached more than 7 points, 0.1 g of bucinnazine hydrochloride was given for supplement. Meantime, same post-operative training methods were adopted in both groups. The resting VAS pain scores, contentment of sedation, incidence of adverse event, postoperative range of motion (ROM) of knee joint and Hospital for Special Surgery (HSS) score were recorded. The resting VAS pain scores at 6 h and 24 h after operation was 5.99 +/- 0.67 scores and 4.26 +/- 0.59 scores in the AAP group respectively, which was significantly lower than that in the control group at the corresponding time (7.02 +/- 0.85 scores and 4.92 +/- 0.43 scores, P < 0.01); but it showed insignificant difference between the two groups at 1 h and 48 h after operation (P > 0.05); sedation contentment in the two groups was similar; incidence of adverse event in the AAP groups seemed lower (4 cases vs. 11 cases), but the intergroup difference was statistically insignificant (P > 0.05). ROM before surgery were 75.63 degrees +/- 5.74 degrees and 75.43 degrees +/- 5.63 degrees in the two groups respectively, showing no significant difference (P > 0.05), two weeks after operation, the initiative ROM raised to 96.50 degrees +/- 3.79 degrees and 93.50 degrees +/- 3.50 degrees, and the passive ROM reached 107.8 degrees +/- 3.37 degrees and 105.27 degrees +/- 3.25 degrees in the two groups respectively, with statistical significance between them (P < 0.05). HSS score was similar between groups before operation (60.23 +/- 3.44 scores vs. 61.70 +/- 2.83 scores, P > 0.05); while it became 86.97 +/- 2.33 scores and 85.37 +/- 2.30 scores after operation, showing significant difference between groups (P < 0.05). Applying auricular acupoint pressing in perioperative period of knee joint replacement is favorable for alleviating postoperative pain, decreasing narcotic consumption, and promoting early rehabilitation, and it has the advantages of low cost, less complication, simple manipulation and high safety.

Classification of high-grade spondylolistheses based on pelvic version and spine balance: possible rationale for reduction.

PubMed

Hresko, Michael T; Labelle, Hubert; Roussouly, Pierre; Berthonnaud, Eric

2007-09-15

Retrospective review of a radiographic database of high-grade spondylolisthesis patients in comparison with asymptomatic controls. To analyze the sagittal spinopelvic alignment in high-grade spondylolisthesis patients and identify subgroups that may require reduction to restore sagittal balance. High-grade spondylolisthesis is associated with an abnormally high pelvic incidence (PI); however, the spatial orientation of the pelvis, determined by sacral slope (SS) and pelvic tilt (PT), is not known. We hypothesized that sagittal spinal alignment would vary with the pelvic orientation. Digitized sagittal radiographs of 133 high-grade spondylolisthesis patients (mean age, 17 years) were measured to determined sagittal alignment. K-means cluster analysis identified 2 groups based on the PT and SS, which were compared by paired t test. Comparisons were made to asymptomatic controls matched for PI. High-grade spondylolisthesis patients had a mean PI of 78.9 degrees +/- 12.1 degrees . Cluster analysis identified a retroverted, unbalanced pelvis group with high PT (36.5 degrees +/- 8.0 degrees )/low SS (40.3 degrees +/- 9.0 degrees ) and a balanced pelvic group with low PT (mean 21.3 degrees +/- 8.2 degrees )/high SS (59.9 degrees +/- 11.2 degrees ). The retroverted pelvis group had significantly greater L5 incidence and lumbosacral angle with less thoracic kyphosis than the balanced pelvic group. A total of 83% of controls had a "balanced pelvis" based on the categorization by SS and PT. Analysis of sagittal alignment of high-grade spondylolisthesis patients revealed distinct groups termed "balanced" and "unbalanced" pelvis. The PT and SS were similar in controls and balanced pelvis patients. Unbalanced pelvis patients had a sagittal spinal alignment that differed from the balanced pelvis and control groups. Treatment strategies for high-grade spondylolisthesis should reflect the different mechanical strain on the spinopelvic junction in each group; reduction techniques might be considered in patients with an unbalanced pelvis high-grade spondylolisthesis.

Elastic and thermal expansion asymmetry in dense molecular materials.

PubMed

Burg, Joseph A; Dauskardt, Reinhold H

2016-09-01

The elastic modulus and coefficient of thermal expansion are fundamental properties of elastically stiff molecular materials and are assumed to be the same (symmetric) under both tension and compression loading. We show that molecular materials can have a marked asymmetric elastic modulus and coefficient of thermal expansion that are inherently related to terminal chemical groups that limit molecular network connectivity. In compression, terminal groups sterically interact to stiffen the network, whereas in tension they interact less and disconnect the network. The existence of asymmetric elastic and thermal expansion behaviour has fundamental implications for computational approaches to molecular materials modelling and practical implications on the thermomechanical strains and associated elastic stresses. We develop a design space to control the degree of elastic asymmetry in molecular materials, a vital step towards understanding their integration into device technologies.

The Noncommutative Doplicher-Fredenhagen-Roberts-Amorim Space

NASA Astrophysics Data System (ADS)

Abreu, Everton M. C.; Mendes, Albert C. R.; Oliveira, Wilson; Zangirolami, Adriano O.

2010-10-01

This work is an effort in order to compose a pedestrian review of the recently elaborated Doplicher, Fredenhagen, Roberts and Amorim (DFRA) noncommutative (NC) space which is a minimal extension of the DFR space. In this DRFA space, the object of noncommutativity (θμν) is a variable of the NC system and has a canonical conjugate momentum. Namely, for instance, in NC quantum mechanics we will show that θij (i,j=1,2,3) is an operator in Hilbert space and we will explore the consequences of this so-called ''operationalization''. The DFRA formalism is constructed in an extended space-time with independent degrees of freedom associated with the object of noncommutativity θμν. We will study the symmetry properties of an extended x+θ space-time, given by the group P', which has the Poincaré group P as a subgroup. The Noether formalism adapted to such extended x+θ (D=4+6) space-time is depicted. A consistent algebra involving the enlarged set of canonical operators is described, which permits one to construct theories that are dynamically invariant under the action of the rotation group. In this framework it is also possible to give dynamics to the NC operator sector, resulting in new features. A consistent classical mechanics formulation is analyzed in such a way that, under quantization, it furnishes a NC quantum theory with interesting results. The Dirac formalism for constrained Hamiltonian systems is considered and the object of noncommutativity θij plays a fundamental role as an independent quantity. Next, we explain the dynamical spacetime symmetries in NC relativistic theories by using the DFRA algebra. It is also explained about the generalized Dirac equation issue, that the fermionic field depends not only on the ordinary coordinates but on θμν as well. The dynamical symmetry content of such fermionic theory is discussed, and we show that its action is invariant under P'. In the last part of this work we analyze the complex scalar fields using this new framework. As said above, in a first quantized formalism, θμν and its canonical momentum πμν are seen as operators living in some Hilbert space. In a second quantized formalism perspective, we show an explicit form for the extended Poincaré generators and the same algebra is generated via generalized Heisenberg relations. We also consider a source term and construct the general solution for the complex scalar fields using the Green function technique.

Inclusion of thoracic spine thrust manipulation into an electro-therapy/thermal program for the management of patients with acute mechanical neck pain: a randomized clinical trial.

PubMed

González-Iglesias, Javier; Fernández-de-las-Peñas, Cesar; Cleland, Joshua A; Alburquerque-Sendín, Francisco; Palomeque-del-Cerro, Luis; Méndez-Sánchez, Roberto

2009-06-01

Our aim was to examine the effects of a seated thoracic spine distraction thrust manipulation included in an electrotherapy/thermal program on pain, disability, and cervical range of motion in patients with acute neck pain. This randomized controlled trial included 45 patients (20 males, 25 females) between 23 and 44 years of age presenting with acute neck pain. Patients were randomly divided into 2 groups: an experimental group which received a thoracic manipulation, and a control group which did not receive the manipulative procedure. Both groups received an electrotherapy program consisting of 6 sessions of TENS (frequency 100Hz; 20min), superficial thermo-therapy (15min) and soft tissue massage. The experimental group also received a thoracic manipulation once a week for 3 consecutive weeks. Outcome measures included neck pain (numerical pain rate scale; NPRS), level of disability (Northwick Park Neck Pain Questionnaire; NPQ) and neck mobility. These outcomes were assessed at baseline and 1 week after discharge. A 2-way repeated-measures ANOVA with group as between-subject variable and time as within-subject variable was used. Patients receiving thoracic manipulation experienced greater reductions in both neck pain, with between-group difference of 2.3 (95% CI 2-2.7) points on a 11-NPRS, and perceived disability with between-group differences 8.5 (95% CI 7.2-9.8) points. Further, patients receiving thoracic manipulation experienced greater increases in all cervical motions with between-group differences of 10.6 degrees (95% CI 8.8-12.5 degrees) for flexion; 9.9 degrees (95% CI 8.1-11.7 degrees) for extension; 9.5 degrees (95% CI 7.6-11.4 degrees) for right lateral-flexion; 8 degrees (95% CI 6.2-9.8 degrees) for left lateral-flexion; 9.6 degrees (95% CI 7.7-11.6 degrees) for right rotation; and 8.4 degrees (95% CI 6.5-10.3 degrees) for left rotation. We found that the inclusion of a thoracic manipulation into an electrotherapy/thermal program was effective in reducing neck pain and disability, and in increasing active cervical mobility in patients with acute neck pain.

Life testing of metal-ceramic CO2 lasers

NASA Technical Reports Server (NTRS)

Fahlen, T. S.; Radecki, D. J.; Reynolds, R. S.; Targ, R.

1971-01-01

The main purpose of this program was to determine the life characteristics of nine space-qualified, metal-ceramic CO2 lasers. Lifetimes ranged between about 400 hours to over 2000 hours (the limit of testing) with a high degree of consistency in like groups. In all cases the tubes which had failed could be restored to near their original power by doubling the cathode current for 30 minutes. Periodic rejuvenation allowed operation for the full 2000 hours on all tubes. The failure mechanism appears to involve formation of NiO and C on the nickel cathode emission surface with subsequent absorption of tube gases.

Constructing an explicit AdS/CFT correspondence with Cartan geometry

NASA Astrophysics Data System (ADS)

Hazboun, Jeffrey S.

2018-04-01

An explicit AdS/CFT correspondence is shown for the Lie group SO (4 , 2). The Lie symmetry structures allow for the construction of two physical theories through the tools of Cartan geometry. One is a gravitational theory that has anti-de Sitter symmetry. The other is also a gravitational theory but is conformally symmetric and lives on 8-dimensional biconformal space. These "extra" four dimensions have the degrees of freedom used to construct a Yang-Mills theory. The two theories, based on AdS or conformal symmetry, have a natural correspondence in the context of their Lie algebras alone where neither SUSY, nor holography, is necessary.

X-ray and conformational investigations of a 4:1 mixture of 6-(N-benzyl-N-tert-butoxycarbonylamino)-2,3,6,7-tetradeoxy-alpha- DL-ery thro- and -beta-DL-threo-hept-2-enopyranos-4-uloses.

PubMed

Krajewski, J W; Urbańczyk-Lipkowska, Z; Gluziński, P; Jurczak, J; Raczko, J; Gołebiowski, A

1990-07-01

The crystals of a 4:1 mixture of 6-(N-benzyl-N-tert-butoxycarbonylamino)-2,3,6,7-tetradeoxy-a-DL-er ythro- and -beta-DL-threo-hept-2-enopyranos-4-ulose were monoclinic, space group P2(1)/c, with cell dimensions: a = 9.490(2), b = 21.516(5), c = 10.279(2) A, beta = 115.31(1) degrees, Z = 4. The ulose ring had a half-chair conformation deformed towards the sofa (envelope) form.

The human role in space. Volume 2: Research analysis and technology report

NASA Technical Reports Server (NTRS)

1984-01-01

The human role in space was studied. The role and the degree of direct involvement of humans that will be required in future space missions are investigated. Valid criteria for allocating functional activities between humans and machines were established. The technology requirements, economics, and benefits of the human presence in space was examined. Topics discussed include: human qualifications for space activities; specific project assessments; technology requirements and tasks; and generalization on human roles in space.

Methods for synthesizing semiconductor quality chalcopyrite crystals for nonlinear optical and radiation detection applications and the like

DOEpatents

Stowe, Ashley; Burger, Arnold

2016-05-10

A method for synthesizing I-III-VI.sub.2 compounds, including: melting a Group III element; adding a Group I element to the melted Group III element at a rate that allows the Group I and Group III elements to react thereby providing a single phase I-III compound; and adding a Group VI element to the single phase I-III compound under heat, with mixing, and/or via vapor transport. The Group III element is melted at a temperature of between about 200 degrees C. and about 700 degrees C. Preferably, the Group I element consists of a neutron absorber and the group III element consists of In or Ga. The Group VI element and the single phase I-III compound are heated to a temperature of between about 700 degrees C. and about 1000 degrees C. Preferably, the Group VI element consists of S, Se, or Te. Optionally, the method also includes doping with a Group IV element activator.

Using SpaceClaimTD Direct for Modeling Components with Complex Geometries for the Thermal Desktop-Based Advanced Stirling Radioisotope Generator Model

NASA Technical Reports Server (NTRS)

Fabanich, William A., Jr.

2014-01-01

SpaceClaim/TD Direct has been used extensively in the development of the Advanced Stirling Radioisotope Generator (ASRG) thermal model. This paper outlines the workflow for that aspect of the task and includes proposed best practices and lessons learned. The ASRG thermal model was developed to predict component temperatures and power output and to provide insight into the prime contractor's thermal modeling efforts. The insulation blocks, heat collectors, and cold side adapter flanges (CSAFs) were modeled with this approach. The model was constructed using mostly TD finite difference (FD) surfaces/solids. However, some complex geometry could not be reproduced with TD primitives while maintaining the desired degree of geometric fidelity. Using SpaceClaim permitted the import of original CAD files and enabled the defeaturing/repair of those geometries. TD Direct (a SpaceClaim add-on from CRTech) adds features that allowed the "mark-up" of that geometry. These so-called "mark-ups" control how finite element (FE) meshes are to be generated through the "tagging" of features (e.g. edges, solids, surfaces). These tags represent parameters that include: submodels, material properties, material orienters, optical properties, and radiation analysis groups. TD aliases were used for most tags to allow analysis to be performed with a variety of parameter values. "Domain-tags" were also attached to individual and groups of surfaces and solids to allow them to be used later within TD to populate objects like, for example, heaters and contactors. These tools allow the user to make changes to the geometry in SpaceClaim and then easily synchronize the mesh in TD without having to redefine the objects each time as one would if using TDMesher. The use of SpaceClaim/TD Direct helps simplify the process for importing existing geometries and in the creation of high fidelity FE meshes to represent complex parts. It also saves time and effort in the subsequent analysis.

Using SpaceClaim/TD Direct for Modeling Components with Complex Geometries for the Thermal Desktop-Based Advanced Stirling Radioisotope Generator Model

NASA Technical Reports Server (NTRS)

Fabanich, William

2014-01-01

SpaceClaim/TD Direct has been used extensively in the development of the Advanced Stirling Radioisotope Generator (ASRG) thermal model. This paper outlines the workflow for that aspect of the task and includes proposed best practices and lessons learned. The ASRG thermal model was developed to predict component temperatures and power output and to provide insight into the prime contractors thermal modeling efforts. The insulation blocks, heat collectors, and cold side adapter flanges (CSAFs) were modeled with this approach. The model was constructed using mostly TD finite difference (FD) surfaces solids. However, some complex geometry could not be reproduced with TD primitives while maintaining the desired degree of geometric fidelity. Using SpaceClaim permitted the import of original CAD files and enabled the defeaturing repair of those geometries. TD Direct (a SpaceClaim add-on from CRTech) adds features that allowed the mark-up of that geometry. These so-called mark-ups control how finite element (FE) meshes were generated and allowed the tagging of features (e.g. edges, solids, surfaces). These tags represent parameters that include: submodels, material properties, material orienters, optical properties, and radiation analysis groups. TD aliases were used for most tags to allow analysis to be performed with a variety of parameter values. Domain-tags were also attached to individual and groups of surfaces and solids to allow them to be used later within TD to populate objects like, for example, heaters and contactors. These tools allow the user to make changes to the geometry in SpaceClaim and then easily synchronize the mesh in TD without having to redefine these objects each time as one would if using TD Mesher.The use of SpaceClaim/TD Direct has helped simplify the process for importing existing geometries and in the creation of high fidelity FE meshes to represent complex parts. It has also saved time and effort in the subsequent analysis.

Process for the synthesis of aliphatic alcohol-containing mixtures

DOEpatents

Greene, Marvin I.; Gelbein, Abraham P.

1984-01-01

A process for the synthesis of mixtures which include saturated aliphatic alcohols is disclosed. In the first step of the process, the first catalyst activation stage, a catalyst, which comprises the oxides of copper, zinc, aluminum, potassium and one or two additional metals selected from the group consisting of chromium, magnesium, cerium, cobalt, thorium and lanthanum, is partially activated. In this step, a reducing gas stream, which includes hydrogen and at least one inert gas, flows past the catalyst at a space velocity of up to 5,000 liters (STP) per hour, per kilogram of catalyst. The partially activated catalyst is then subjected to the second step of the process, second-stage catalyst activation. In this step, the catalyst is contacted by an activation gas stream comprising hydrogen and carbon monoxide present in a volume ratio of 0.5:1 and 4:1, respectively, at a temperature of 200.degree. to 450.degree. C. and a pressure of between 35 and 200 atmospheres. The activation gas flows at a space velocity of from 1,000 to 20,000 liters (STP) per hour, per kilogram of catalyst. Second-stage activation continues until the catalyst is contacted with at least 500,000 liters (STP) of activation gas per kilogram of catalyst. The fully activated catalyst, in the third step of the process, contacts a synthesis gas stream comprising hydrogen and carbon monoxide.

Structural Network Position and Performance of Health Leaders Within an HIV Prevention Trial.

PubMed

Mulawa, Marta I; Yamanis, Thespina J; Kajula, Lusajo J; Balvanz, Peter; Maman, Suzanne

2018-04-28

The effectiveness of peer leaders in promoting health may depend on the position they occupy within their social networks. Using sociocentric (whole network) and behavioral data from the intervention arm of a cluster-randomized HIV prevention trial in Dar es Salaam, Tanzania, we used generalized linear models with standardized predictors to examine the association between heath leaders' baseline structural network position (i.e., in-degree and betweenness centrality) and their 12-month self-reported (1) confidence in educating network members about HIV and gender-based violence (GBV) and (2) number of past-week conversations about HIV and GBV. As in-degree centrality increased, leaders reported fewer HIV-related conversations. As betweenness centrality increased, leaders reported greater number of conversations about GBV. Network position was not significantly associated with confidence in discussing either topic. Our results suggest that peer leaders who occupy spaces between sub-groups of network members may be more effective in engaging their peers in sensitive or controversial topics like GBV than more popular peer leaders.

An internal affinity-tag for purification and crystallization of the siderophore receptor FhuA, integral outer membrane protein from Escherichia coli K-12.

PubMed

Ferguson, A D; Breed, J; Diederichs, K; Welte, W; Coulton, J W

1998-07-01

FhuA (Mr 78,992, 714 amino acids), siderophore receptor for ferrichrome-iron in the outer membrane of Escherichia coli, was affinity tagged, rapidly purified, and crystallized. To obtain FhuA in quantities sufficient for crystallization, a hexahistidine tag was genetically inserted into the fhuA gene after amino acid 405, which resides in a known surface-exposed loop. Recombinant FhuA405.H6 was overexpressed in an E. coli strain that is devoid of several major porins and using metal-chelate chromatography was purified in large amounts to homogeneity. FhuA crystals were grown using the hanging drop vapor diffusion technique and were suitable for X-ray diffraction analysis. On a rotating anode X-ray source, diffraction was observed to 3.0 A resolution. The crystals belong to space group P6(1) or P6(5) with unit cell dimensions of a=b=174 A, c=88 A (alpha=beta=90 degrees, gamma=120 degrees).

Are Khovanov-Rozansky polynomials consistent with evolution in the space of knots?

NASA Astrophysics Data System (ADS)

Anokhina, A.; Morozov, A.

2018-04-01

R-coloured knot polynomials for m-strand torus knots Torus [ m, n] are described by the Rosso-Jones formula, which is an example of evolution in n with Lyapunov exponents, labelled by Young diagrams from R ⊗ m . This means that they satisfy a finite-difference equation (recursion) of finite degree. For the gauge group SL( N ) only diagrams with no more than N lines can contribute and the recursion degree is reduced. We claim that these properties (evolution/recursion and reduction) persist for Khovanov-Rozansky (KR) polynomials, obtained by additional factorization modulo 1 + t, which is not yet adequately described in quantum field theory. Also preserved is some weakened version of differential expansion, which is responsible at least for a simple relation between reduced and unreduced Khovanov polynomials. However, in the KR case evolution is incompatible with the mirror symmetry under the change n -→ - n, what can signal about an ambiguity in the KR factorization even for torus knots.

Feasibility and effects of the semirecumbent position to prevent ventilator-associated pneumonia: a randomized study.

PubMed

van Nieuwenhoven, Christianne A; Vandenbroucke-Grauls, Christine; van Tiel, Frank H; Joore, Hans C A; van Schijndel, Rob J M Strack; van der Tweel, Ingeborg; Ramsay, Graham; Bonten, Marc J M

2006-02-01

Reducing aspiration of gastric contents by placing mechanically ventilated patients in a semirecumbent position has been associated with lower incidences of ventilator-associated pneumonia (VAP). The feasibility and efficacy of this intervention in a larger patient population, however, are unknown. Assessment of the feasibility of the semirecumbent position for intensive care unit patients and its influence on development of VAP. In a prospective multicentered trial, critically ill patients undergoing mechanical ventilation were randomly assigned to the semirecumbent position, with a target backrest elevation of 45 degrees , or standard care (i.e., supine position) with a backrest elevation of 10 degrees . Backrest elevation was measured continuously during the first week of ventilation with a monitor-linked device. A deviation of position was defined as a change of the randomized position >5 degrees . Diagnosis of VAP was made by quantitative cultures of samples obtained by bronchoscopic techniques. One hundred nine patients were assigned to the supine group and 112 to the semirecumbent group. Baseline characteristics were comparable for both groups. Average elevations were 9.8 degrees and 16.1 degrees at day 1 and day 7, respectively, for the supine group and 28.1 degrees and 22.6 degrees at day 1 and day 7, respectively, for the semirecumbent group (p < .001). The target semirecumbent position of 45 degrees was not achieved for 85% of the study time, and these patients more frequently changed position than supine-positioned patients. VAP was diagnosed in eight patients (6.5%) in the supine group and in 13 (10.7%) in the semirecumbent group (NS), after a mean of 6 (range, 3-9) and 7 (range, 3-12) days, respectively. There were no differences in numbers of patients undergoing enteral feeding, receiving stress ulcer prophylaxis, or developing pressure sores or in mortality rates or duration of ventilation and intensive care unit stay between the groups. The targeted backrest elevation of 45 degrees for semirecumbent positioning was not reached in the conditions of the present randomized study. The achieved difference in treatment position (28 degrees vs. 10 degrees ) did not prevent the development of VAP.

Impact of water temperature and stressor controllability on swim stress-induced changes in body temperature, serum corticosterone, and immobility in rats.

PubMed

Drugan, Robert C; Eren, Senem; Hazi, Agnes; Silva, Jennifer; Christianson, John P; Kent, Stephen

2005-10-01

The present study compared the effects of three different water temperatures (20, 25, and 30 degrees C) and stressor controllability on several physiological and behavioral endpoints in an intermittent swim stress paradigm. The escape latency of rats in the 20 and 25 degrees C water was less than that observed for the 30 degrees C group. Both escape and yoked groups at 20 and 25 degrees C exhibited moderate to severe hypothermia following the swim stress session that returned to prestress levels 30-40 min post-stress. At 30 degrees C core body temperature (Tb) only decreased by 1 degree C for either swim group. Following swim, serum corticosterone (CORT) levels were significantly elevated in both escape and yoked groups in comparison to confined and home cage controls. The confined control group showed a significant elevation that was approximately halfway between the home cage control and the swim stress groups. At 30 degrees C, there was still a significant elevation of serum CORT in both swim groups in comparison to confined and home cage controls. Therefore, 30 degrees C appears to be the optimal water temperature to evaluate stress controllability effects in the current paradigm. In a final experiment, swim stressor controllability effects were examined in a 5 min forced swim test (FST) 24 h following the initial stress exposure. Rats exposed to yoked-inescapable swim stress at 30 degrees C exhibited more immobility than their escapable swim stress and confined counterparts, while the escape and confined controls did not differ. These results demonstrate that the behavioral deficits observed in the FST are attributable to the stress of inescapable swim and not swim stress per se.

ATFL elongation after Brostrom procedure: a biomechanical investigation.

PubMed

Kirk, Kevin L; Campbell, John T; Guyton, Gregory P; Parks, Brent G; Schon, Lew C

2008-11-01

Elongation of ligaments during early mobilization after reconstruction may be associated with decreased stability. We evaluated elongation of the anterior talofibular ligament (ATFL) before and after lateral ligament reconstruction within a physiologic range of motion with protected and unprotected, isolated dorsiflexion/plantarflexion range of motion. Six fresh frozen cadaver legs were used with the ATFL meticulously dissected. A differential variable reluctance transducer (DVRT) was spaced to span the course of the ATFL using consistent placement points based on previous reports. Elongation was measured in a load frame with protected motion of 30 degrees plantarflexion and 10 degrees dorsiflexion for the intact and sectioned ATFL and for the repaired specimen with and without protected motion. The proximal DVRT anchor point was detached for sectioning and repair of the ATFL and replaced at the same position. Testing was 1000 cycles at 1 Hz for the repaired protected specimen and 10 cycles at 1 Hz for all other stages. Initial elongation in the unprotected, repaired group was significantly higher than initial elongation in the intact (p < 0.01), sectioned (p = 0.02), and repaired, protected (p < 0.01) groups. Final elongation in the unprotected repaired group was also higher than final elongation in all other groups (p < 0.01 for all comparisons). The use of protected range of motion of the ankle after lateral ankle ligament reconstruction was not associated with elongation of the ATFL. The ATFL elongated significantly by comparison without protected dorsiflexion/plantarflexion. The study provides biomechanical support for the safety of early protected dorsiflexion/plantarflexion range of motion after Broström reconstruction.

Reagent Anions for Charge Inversion of Polypeptide/Protein Cations in the Gas Phase

PubMed Central

He, Min; Emory, Joshua F.; McLuckey, Scott A.

2005-01-01

Various reagent anions capable of converting polypeptide cations to anions via ion/ion reactions have been investigated. The major charge inversion reaction channels include multiple proton transfer and adduct formation. Dianions composed of sulfonate groups as the negative charge carriers show essentially exclusive adduct formation in converting protonated peptides and proteins to anions. Dianions composed of carboxylate groups, on the other hand, show far more charge inversion via multiple proton transfer, with the degree of adduct formation dependent upon both the size of the polypeptide and the spacings between carboxylate groups in the dianion. More highly charged carboxylate-containing anions, such as those derived from carboxylate-terminated polyamidoamine half-generation dendrimers show charge inversion to give anion charges as high in magnitude as −4, with the degree of adduct formation being inversely related to dendrimer generation. All observations can be interpreted on the basis of charge inversion taking place via a long-lived chemical complex. The lifetime of this complex is related to the strengths and numbers of the interactions of the reactants in the complex. Calculations with model systems are fully consistent with sulfonate groups giving rise to more stable complexes. The kinetic stability of the complex can also be affected by the presence of electrostatic repulsion if it is multiply charged. In general, this situation destabilizes the complex and reduces the likelihood for observation of adducts. The findings highlight the characteristics of multiply charged anions that play roles in determining the nature of charge inversion products associated with protonated peptides and proteins. PMID:15889906

Visuo-spatial knowledge acquisition in individuals with Down syndrome: The role of descriptions and sketch maps.

PubMed

Meneghetti, Chiara; Lanfranchi, Silvia; Carretti, Barbara; Toffalini, Enrico

2017-04-01

Few studies on individuals with Down syndrome (DS) have explored how they learn space. The present study examines space learning from verbal descriptions in individuals with DS, and explores the role of external cues (such as a sketch map). Twenty-eight individuals with DS and 28 matched typically-developing (TD) children listened to route or survey descriptions with or without seeing a corresponding sketch map (Description+Sketch Map [D+SM] and Description alone [D], respectively). After hearing each description, they performed tasks that involved recognizing, arranging sequentially, and locating landmarks. The results showed that individuals with DS performed less well in recognizing landmarks and arranging them sequentially. The D+SM condition produced general benefits in both groups' accuracy, though the improvement in locating landmarks was greater in the TD than in the DS group. In both groups, the D+SM condition prompted a better performance than the D condition when participants arranged landmarks sequentially after hearing a description from a route perspective, but not from a survey perspective. Overall, our results show that individuals with DS benefited when a spatial description was associated with a corresponding sketch map, albeit to a lesser degree than TD children. The findings are discussed in the light of the literature on DS and on spatial cognition in the TD domain. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fully Three-Dimensional Virtual-Reality System

NASA Technical Reports Server (NTRS)

Beckman, Brian C.

1994-01-01

Proposed virtual-reality system presents visual displays to simulate free flight in three-dimensional space. System, virtual space pod, is testbed for control and navigation schemes. Unlike most virtual-reality systems, virtual space pod would not depend for orientation on ground plane, which hinders free flight in three dimensions. Space pod provides comfortable seating, convenient controls, and dynamic virtual-space images for virtual traveler. Controls include buttons plus joysticks with six degrees of freedom.

Syntheses, Structural Characterization and Thermoanalysis of Transition-Metal Compounds Derived from 3,5-Dinitropyridone.

PubMed

Fan, Rong; Zhou, Qiu-Ping; Zhang, Guo-Fang; Cai, Mei-Yu; Li, Ping; Gan, Li-Hua; Zhao, Feng-Qi; Li, Ji-Zhen; Fan, Xue-Zhong; Ng, Seik Weng

2009-09-28

Nine metal compounds of Mn(II), Zn(II) and Cd(II) derived from dinitropyridone ligands (3,5-dinitro-pyrid-2-one, 2HDNP; 3,5-dinitropyrid-4-one, 4HDNP and 3,5-dinitropyrid-4-one-N- hydroxide, 4HDNPO) were characterized by elemental analysis, FT-IR and partly by TG-DSC. Three of which were further structurally characterized by X-ray single-crystal diffraction analysis. The structures of the three compounds, Mn(4DNP)(2)(H(2)O)(4), 4, Zn(4DNPO)(2)(H(2)O)(4), 8, and Cd(4DNPO)(2)(H(2)O)(4), 9, crystallize in the monoclinic space group P2(1)/n and Z = 2, with a = 8.9281(9), b = 9.1053(9), c = 10.6881(11) A, beta = 97.9840(10) degrees for 4; a = 8.4154(7), b = 9.9806(8), c = 10.5695(8) A, beta = 97.3500(10) degrees for 8; a = 8.5072(7), b = 10.2254(8), c = 10.5075(8) A, beta 96.6500(10) degrees for 9. All three complexes are octahedral consisting of four equatorial water molecules, and two nitrogen or oxygen donor ligands (DNP or DNPO). The abundant hydrogen-bonding and pi-pi stacking interactions seem to contribute to stabilization of the crystal structures of the compounds. The TG-DTG results revealed that the complexes showed a weight loss sequence corresponding to all coordinated water molecules, nitro groups, the breaking of the pyridine rings and finally the formation of metal oxides.

Patients with type 2 diabetes demonstrate proprioceptive deficit in the knee

PubMed Central

Ettinger, Lucas Richard; Boucher, Ami; Simonovich, Elisabeth

2018-01-01

AIM To investigate proprioceptive discrepancies in the lower extremity in persons with type 2 diabetes mellitus (T2DM). METHODS In this cross-sectional study, a total of 46 older persons were divided into a T2DM group (n = 23) and a control group who did not have T2DM (n = 23). Participants were given a brief warm up with stretching exercises. Diabetic neuropathy scores were collected prior to proprioceptive testing. For proprioceptive testing, participants performed leg extensions to randomized target positions of 15°, 30°, 45, 60° degrees of elevation in the sagittal plane, each target was repeated a total of four times. Subjects were guided to target positions in the absence of visual feedback via auditory cues from a custom JPS application. When the participant entered the target position, they memorized the location of their limb in space and subsequently attempted to re-locate this position in space. Proprioceptive errors were measured from the target positioned, target remembered, target repositioned protocol. RESULTS Proprioceptive accuracy was lower in the diabetic group at all levels of target angle than the control group (P < 0.05). The diabetic group had 46% greater inaccuracy than the control group at all levels of target position. Diabetics also reported greater neuropathy scores than controls in the past 12 mo P < 0.01. CONCLUSION Deficits in lower limb localization and greater diabetic neuropathy scores were identified in this study. Our findings may be associated with deafferentation as peripheral neuropathy is a common complication with the disease. These findings may help to explain the declining balance function in the older persons with T2DM which is also commonly reported. PMID:29607003

Three-dimensional Identification and Reconstruction of Galaxy Systems within Flux-limited Redshift Surveys

NASA Astrophysics Data System (ADS)

Marinoni, Christian; Davis, Marc; Newman, Jeffrey A.; Coil, Alison L.

2002-11-01

We have developed a new geometrical method for identifying and reconstructing a homogeneous and highly complete set of galaxy groups within flux-limited redshift surveys. Our method combines information from the three-dimensional Voronoi diagram and its dual, the Delaunay triangulation, to obtain group and cluster catalogs that are remarkably robust over wide ranges in redshift and degree of density enhancement. As free by-products, this Voronoi-Delaunay method (VDM) provides a nonparametric measurement of the galaxy density around each object observed and a quantitative measure of the distribution of cosmological voids in the survey volume. In this paper, we describe the VDM algorithm in detail and test its effectiveness using a family of mock catalogs that simulate the Deep Extragalactic Evolutionary Probe (DEEP2) Redshift Survey, which should present at least as much challenge to cluster reconstruction methods as any other near-future survey that is capable of resolving their velocity dispersions. Using these mock DEEP2 catalogs, we demonstrate that the VDM algorithm can be used to identify a homogeneous set of groups in a magnitude-limited sample throughout the survey redshift window 0.7~400 km s-1. Finally, we argue that the bivariate distribution of systems as a function of redshift and velocity dispersion reconstructed with these techniques reproduces with high fidelity the underlying real space distribution and can thus be used robustly to constrain cosmological parameters. We expect that the VDM algorithm, which has performed so well when faced with the challenges posed by the DEEP2 survey, should only be more effective when applied to the better sampled, larger surveys of the local universe now underway.

STUDY CARRELS, DESIGNS FOR INDEPENDENT STUDY SPACE.

ERIC Educational Resources Information Center

BEYNON, JOHN

BECAUSE OF THE DEMAND FOR INDIVIDUALIZED INSTRUCTION, NEW SCHOOLS ARE BEING PLANNED WITH LESS CLASSROOM SPACE AND MORE LIBRARY AND INDIVIDUAL STUDY SPACES. THESE NEW SCHOOLS REQUIRE NEW KINDS OF FURNITURE DESIGNED PRIMARILY TO GIVE THE STUDENT A DEGREE OF PRIVACY RATHER THAN TO PROVIDE OPTIMUM CONTROL TO TEACHERS. THE CARREL, PREVIOUSLY USED…

Space Separatism: Degree of Differentiation

DTIC Science & Technology

2014-12-01

Separate Service” (Norfolk, VA: Joint Forces Staff College, 6 September 2002); MAJ William S. Moncrief , “Building a United States Space Force,” Army Space...unclassified b. ABSTRACT unclassified c . THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 November–December 2014 Air...FY14_Green_Book.pdf. 32. Story, “Separate Space Force,” 2–5. 33. Moncrief , “Building a United States Space Force,” 34–38. 34. DODD 3100.10, Space Policy, 3. 35. Lt

Rhesus monkeys (Macaca mulatta) map number onto space.

PubMed

Drucker, Caroline B; Brannon, Elizabeth M

2014-07-01

Humans map number onto space. However, the origins of this association, and particularly the degree to which it depends upon cultural experience, are not fully understood. Here we provide the first demonstration of a number-space mapping in a non-human primate. We trained four adult male rhesus macaques (Macaca mulatta) to select the fourth position from the bottom of a five-element vertical array. Monkeys maintained a preference to choose the fourth position through changes in the appearance, location, and spacing of the vertical array. We next asked whether monkeys show a spatially-oriented number mapping by testing their responses to the same five-element stimulus array rotated ninety degrees into a horizontal line. In these horizontal probe trials, monkeys preferentially selected the fourth position from the left, but not the fourth position from the right. Our results indicate that rhesus macaques map number onto space, suggesting that the association between number and space in human cognition is not purely a result of cultural experience and instead has deep evolutionary roots. Copyright © 2014 Elsevier B.V. All rights reserved.

Equivalence of linear canonical transform domains to fractional Fourier domains and the bicanonical width product: a generalization of the space-bandwidth product.

PubMed

Oktem, Figen S; Ozaktas, Haldun M

2010-08-01

Linear canonical transforms (LCTs) form a three-parameter family of integral transforms with wide application in optics. We show that LCT domains correspond to scaled fractional Fourier domains and thus to scaled oblique axes in the space-frequency plane. This allows LCT domains to be labeled and ordered by the corresponding fractional order parameter and provides insight into the evolution of light through an optical system modeled by LCTs. If a set of signals is highly confined to finite intervals in two arbitrary LCT domains, the space-frequency (phase space) support is a parallelogram. The number of degrees of freedom of this set of signals is given by the area of this parallelogram, which is equal to the bicanonical width product but usually smaller than the conventional space-bandwidth product. The bicanonical width product, which is a generalization of the space-bandwidth product, can provide a tighter measure of the actual number of degrees of freedom, and allows us to represent and process signals with fewer samples.

HP-9825A HFRMP trajectory processor (#TRAJ), detailed description. [relative motion of the space shuttle orbiter and a free-flying payload

NASA Technical Reports Server (NTRS)

Kindall, S. M.

1980-01-01

The computer code for the trajectory processor (#TRAJ) of the high fidelity relative motion program is described. The #TRAJ processor is a 12-degrees-of-freedom trajectory integrator (6 degrees of freedom for each of two vehicles) which can be used to generate digital and graphical data describing the relative motion of the Space Shuttle Orbiter and a free-flying cylindrical payload. A listing of the code, coding standards and conventions, detailed flow charts, and discussions of the computational logic are included.

Space Radar Image of Baikal Lake, Russia

NASA Technical Reports Server (NTRS)

1994-01-01

This is an X-band black-and-white image of the forests east of the Baikal Forest in the Jablonowy Mountains of Russia. The image is centered at 52.5 degrees north latitude and 116 degrees east longitude near the mining town of Bukatschatscha. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar aboard the space shuttle Endeavour on October 4, 1994, during the second flight of the spaceborne radar. This area is part of an international research project known as the Taiga Aerospace Investigation using Geographic Information System Applications.

Percutaneous pedicle screw fixation through the pedicle of fractured vertebra in the treatment of type A thoracolumbar fractures using Sextant system: an analysis of 38 cases.

PubMed

Wang, Hong-wei; Li, Chang-qing; Zhou, Yue; Zhang, Zheng-feng; Wang, Jian; Chu, Tong-wei

2010-06-01

To prospectively evaluate the feasibility, safety and efficacy of the percutaneous pedicle screw fixation through the pedicle of fractured vertebra in the treatment of type A thoracolumbar fractures using Sextant system in the retrospective non-randomized case-control study. A total of 38 consecutive non-randomized patients with type A thoracolumbar fractures, which had been stabilized posteriorly from December 2006 to March 2009, were examined retrospectively more than 9 months after surgery. Twenty-one patients had been treated conventionally with open pedicle screw fixation (OPSF) and 17 patients received minimally invasive treatment with Sextant percutaneous pedicle screw fixation (SPPSF). As a method of evaluation, the incision size, the intraoperation and postoperative volume of blood loss, operation time, postoperative hospital stay, blood transfusion, the radiological assessment of the sagittal Cobb;s angle, vertebral body angle and vertebral body height were recorded and compared. All patients were followed up for 8-24 months (average 11.6 months). There were significant differences in the incision size, surgical blood loss, surgical draining loss, operation time, hospital stay after operation, blood transfusion, the proportion of antalgic supplement and postoperative incisional VAS between the two groups (P less than 0.05). Mean preoperative kyphotic deformity was 16.0 degree and improved by 9.3 degree after surgery in OPSF group, but 15.2 degree and 10.3 degree respectively in SPPSF group. Mean preoperative angle of the fractured vertebral body was 15.9 degree and improved by 7.9 degree after surgery in OPSF group, but 14.9 degree and 6.6 degree respectively in SPPSF group. Mean anterior vertebral body height (% of normal) was 67.3% before surgery and 95.8% after surgery, but 69.1% and 90.1% respectively in SPPSF group. Mean posterior vertebral body height (% of normal) was 93.3% before surgery and 99.5% after surgery, but 88.9% and 93.3% respectively in SPPSF group. Among the patients whose 9-month follow-up films were available, 3.0 degree of kyphosis correction was lost in OPSF group, but 3.2 degree in SPPSF group. And 1.0 degree of the angle of the fractured vertebral body correction was lost in OPSF group, but 1.5 degree in SPPSF group. Then 3.0% of the anterior vertebral body height correction was lost in OPSF group, but 2.2% in SPPSF group. And 3.0% of the posterior vertebral body height correction was lost in OPSF group, but 2.5% in SPPSF group. The sagittal Cobb's angle, vertebral body angle and anterior height of the fractured vertebra were all significantly different in each group before and after operation (P less than 0.05). There were no significant differences in the postoperative sagittal Cobb's angle, vertebral body angle and the improvement of the vertebral body height and the kyphotic deformity correction between OPSF and SPPSF groups (P larger than 0.05), but there was significant difference in the postoperative anterior height of the fractured vertebra between the two groups (P less than 0.05). The percutaneous pedicle screw fixation through the pedicle of fractured vertebra using Sextant system is a good minimally-invasive surgical therapeutic choice for patients with type A thoracolumbar fracture except for that the SPPSF has a little insufficiency in resuming the anterior height of the fractured vertebra compared with OPSF.

Thermal coefficients of the methyl groups within ubiquitin

PubMed Central

Sabo, T Michael; Bakhtiari, Davood; Walter, Korvin F A; McFeeters, Robert L; Giller, Karin; Becker, Stefan; Griesinger, Christian; Lee, Donghan

2012-01-01

Physiological processes such as protein folding and molecular recognition are intricately linked to their dynamic signature, which is reflected in their thermal coefficient. In addition, the local conformational entropy is directly related to the degrees of freedom, which each residue possesses within its conformational space. Therefore, the temperature dependence of the local conformational entropy may provide insight into understanding how local dynamics may affect the stability of proteins. Here, we analyze the temperature dependence of internal methyl group dynamics derived from the cross-correlated relaxation between dipolar couplings of two CH bonds within ubiquitin. Spanning a temperature range from 275 to 308 K, internal methyl group dynamics tend to increase with increasing temperature, which translates to a general increase in local conformational entropy. With this data measured over multiple temperatures, the thermal coefficient of the methyl group order parameter, the characteristic thermal coefficient, and the local heat capacity were obtained. By analyzing the distribution of methyl group thermal coefficients within ubiquitin, we found that the N-terminal region has relatively high thermostability. These results indicate that methyl groups contribute quite appreciably to the total heat capacity of ubiquitin through the regulation of local conformational entropy. PMID:22334336

Bialgebra cohomology, deformations, and quantum groups.

PubMed Central

Gerstenhaber, M; Schack, S D

1990-01-01

We introduce cohomology and deformation theories for a bialgebra A (over a commutative unital ring k) such that the second cohomology group is the space of infinitesimal deformations. Our theory gives a natural identification between the underlying k-modules of the original and the deformed bialgebra. Certain explicit deformation formulas are given for the construction of quantum groups--i.e., Hopf algebras that are neither commutative nor cocommutative (whether or not they arise from quantum Yang-Baxter operators). These formulas yield, in particular, all GLq(n) and SLq(n) as deformations of GL(n) and SL(n). Using a Hodge decomposition of the underlying cochain complex, we compute our cohomology for GL(n). With this, we show that every deformation of GL(n) is equivalent to one in which the comultiplication is unchanged, not merely on elements of degree one but on all elements (settling in the strongest way a decade-old conjecture) and in which the quantum determinant, as an element of the underlying k-module, is identical with the usual one. PMID:11607053

Trapped atomic ions for quantum-limited metrology

NASA Astrophysics Data System (ADS)

Wineland, David

2017-04-01

Laser-beam-manipulated trapped ions are a candidate for large-scale quantum information processing and quantum simulation but the basic techniques used can also be applied to quantum-limited metrology and sensing. Some examples being explored at NIST are: 1) As charged harmonic oscillators, trapped ions can be used to sense electric fields; this can be used to characterize the electrode-surface-based noisy electric fields that compromise logic-gate fidelities and may eventually be used as a tool in surface science. 2) Since typical qubit logic gates depend on state-dependent forces, we can adapt the gate dynamics to sensitively detect additional forces. 3) We can use extensions of Bell inequality measurements to further restrict the degree of local realism possessed by Bell states. 4) We also briefly describe experiments for creation of Bell states using Hilbert space engineering. This work is a joint effort including the Ion-Storage group, the Quantum processing group, and the Computing and Communications Theory group at NIST, Boulder. Supported by IARPA, ONR, and the NIST Quantum Information Program.

Color group selection for computer interfaces

NASA Astrophysics Data System (ADS)

Lyons, Paul; Moretti, Giovanni; Wilson, Mark

2000-06-01

We describe a low-impact method for coloring interfaces harmoniously. The method uses a model that characterizes the overall image including the need for distinguishability between interface components. The degree of visual distinction between one component and other components, and its color strength (which increases with its importance and decreases with its size and longevity), are used in generating a rigid ball-and-stick 'color molecule,' which represents the color relationships between the interface components. The shape of the color molecule is chosen to conform to standard principles of color harmony (like colors harmonize, complementary colors harmonize, cycles in the color space harmonize, and so on). The color molecule's shape is fixed, but its position and orientation within the perceptually uniform color solid are not. The end user of the application chooses a new color scheme for the complete interface by repositioning the molecule within the color space. The molecule's shape and rigidity, and the space's perceptual uniformity, ensures the distinguishability and color harmony of the components are maintained. The system produces a selection of color schemes which often include subtle 'nameless' colors that people rarely choose using conventional color controls, but which blend smoothly into a harmonious color scheme. A new set of equally harmonious color schemes only requires repositioning the color molecule within the space.

Atlantis and Payload on Approach to ISS during the STS-132 Mission

NASA Image and Video Library

2010-05-16

ISS023-E-044611 (16 May 2010) --- Flying above the Atlantic coast of Spain and the Gulf of Cadiz, the space shuttle Atlantis is shown making its relative approach to the International Space Station, from which this photo was taken. The tip of a Russian spacecraft, temporarily docked to the orbital outpost can be seen at top center. The coast includes the city of Ayamonte (left of image as photographed), past Huelva (under Atlantis), past the sand dunes, the Rio Guadalquivir, to the city of Rota. Center point coordinates of the area pictured in the image are 37.3 degrees north latitude and 6.7 degrees west longitude. Photo credit: NASA or National Aeronautics and Space Administration

Lightweight Shield Against Space Debris

NASA Technical Reports Server (NTRS)

Redmon, John W., Jr.; Lawson, Bobby E.; Miller, Andre E.; Cobb, W. E.

1992-01-01

Report presents concept for lightweight, deployable shield protecting orbiting spacecraft against meteoroids and debris, and functions as barrier to conductive and radiative losses of heat. Shield made in four segments providing 360 degree coverage of cylindrical space-station module.

Crystal structure determination of new antimitotic agent bis(p-fluorobenzyl)trisulfide.

PubMed

An, Haoyun; Hu, Xiurong; Gu, Jianming; Chen, Linshen; Xu, Weiming; Mo, Xiaopeng; Xu, Wanhong; Wang, Xiaobo; Xu, Xiao

2008-01-01

The purpose of this research was to investigate the physical characteristics and crystalline structure of bis(p-fluorobenzyl)trisulfide, a new anti-tumor agent. Methods used included X-ray single crystal diffraction, X-ray powder diffraction (XRPD), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetric (DSC) and thermogravimetric (TG) analyses. The findings obtained with X-ray single crystal diffraction showed that a monoclinic unit cell was a = 12.266(1) A, b = 4.7757(4) A, c = 25.510(1) A, beta = 104.25(1) degrees ; cell volume = 1,448.4(2) A(3), Z = 4, and space group C2/c. The XRPD studies of the four crystalline samples, obtained by recrystallization from four different solvents, indicated that they had the same diffraction patterns. The diffraction pattern stimulated from the crystal structure data is in excellent agreement with the experimental results. In addition, the identical FT-IR spectra of the four crystalline samples revealed absorption bands corresponding to S-S and C-S stretching as well as the characteristic aromatic substitution. Five percent weight loss at 163.3 degrees C was observed when TG was used to study the decomposition process in the temperature range of 20-200 degrees C. DSC also allowed for the determination of onset temperatures at 60.4(1)-60.7(3) degrees C and peak temperatures at 62.1(3)-62.4(3) degrees C for the four crystalline samples studied. The results verified that the single crystal structure shared the same crystal form with the four crystalline samples investigated.

Effective degrees of freedom of a random walk on a fractal

NASA Astrophysics Data System (ADS)

Balankin, Alexander S.

2015-12-01

We argue that a non-Markovian random walk on a fractal can be treated as a Markovian process in a fractional dimensional space with a suitable metric. This allows us to define the fractional dimensional space allied to the fractal as the ν -dimensional space Fν equipped with the metric induced by the fractal topology. The relation between the number of effective spatial degrees of freedom of walkers on the fractal (ν ) and fractal dimensionalities is deduced. The intrinsic time of random walk in Fν is inferred. The Laplacian operator in Fν is constructed. This allows us to map physical problems on fractals into the corresponding problems in Fν. In this way, essential features of physics on fractals are revealed. Particularly, subdiffusion on path-connected fractals is elucidated. The Coulomb potential of a point charge on a fractal embedded in the Euclidean space is derived. Intriguing attributes of some types of fractals are highlighted.

Redox interplay of oxo-thio-tungsten centers with sulfur-donor co-ligands.

PubMed

Thomas, Simon; Eagle, Aston A; Sproules, Stephen A; Hill, Jason P; White, Jonathan M; Tiekink, Edward R T; George, Graham N; Young, Charles G

2003-09-22

The oxo-thio-W(VI) complexes TpWOS(S(2)PR(2)-S) and TpWOS(pyS-S) (Tp = hydrotris(3,5-dimethylpyrazol-1-yl)borate, R = OEt, Ph; pyS = pyridine-2-thiolate) have been prepared and characterized by microanalytical, spectroscopic, and structural techniques. Crystals of the 1,2-dichloroethane hemisolvate of TpWOS(S(2)PPh(2)-S) belong to the triclinic space group Ponemacr; with a = 10.732(6) A, b = 16.91(1) A, c = 10.021(4) A, alpha = 104.40(4) degrees, beta = 107.52(3) degrees, gamma = 96.09(5) degrees, V = 1647(1) A(3) for Z = 2. The complex exhibits a distorted octahedral structure featuring a facial tridentate Tp ligand and mutually cis terminal oxo (W-O(1) = 1.712(7) A), terminal thio (W-S(1) = 2.162(3) A), and monodentate dithiophosphinate ligands. X-ray absorption and extended X-ray absorption fine structure results support a related oxo-thio formulation for TpWOS(pyS-S). The complexes are reduced to the corresponding oxo-thio-W(V) anions, [TpWOS(S(2)PR(2)-S)](-) and [TpWOS(pyS-S)](-), which exhibit highly anisotropic EPR spectra. They are oxidized to form the EPR-active (dithio)oxo-W(V) cations, [TpWO(S(3)PR(2)-S,S')](+) and [TpWO(pyS(2)-N,S)](+) (pyS(2) = pyridine-2-dithio). Green [TpWO(pyS(2)-N,S)]BF(4), formed in the reaction of TpWOS(pyS) and NOBF(4), has been isolated and spectroscopically and structurally characterized. Crystals of [TpWO(pyS(2)-N,S)]BF(4) belong to the monoclinic space group Cc with a = 16.007(5) A, b = 14.091(4) A, c = 13.608(4) A, beta = 124.525(4) degrees, V = 2528.8(13) A(3) for Z = 4. The cation exhibits a distorted octahedral structure featuring facial tridentate Tp, terminal oxo (W-O(1) = 1.632(12) A), and bidentate pyridine-2-dithio-N,S (W-S(1) = 2.317(7) A, S(1)-S(2) = 2.037(9) A) ligands. The structures and redox behavior of the complexes are compared and contrasted with those of the related molybdenum complexes, TpMo(VI)OS(S(2)PR(2)-S) and TpMo(IV)O(pyS(2)-N,S) (Hill, J. P.; Laughlin, L. J.; Gable, R. W.; Young, C. G. Inorg. Chem. 1996, 35, 3447).

Effect of Crown Angulation of Maxillary Incisor on Effective Arch Perimeter.

PubMed

Jain, Megha; Vyas, Matrishva; Singh, Johar Rajvinder

2017-06-01

It has been postulated that crown angulation and inclination has potential space implication within the arch. With the insight of space implication of the axial relations of teeth, cases of genuine tooth size discrepancies can be dealt with improved stability. This in vitro study was designed to investigate and quantify the influence of angulation and inclination of maxillary incisors on the effective arch perimeter. Acrylic teeth were arranged over typhodont frame with spaced maxillary anterior segment. Known value of tip and torque in increments were incorporated to maxillary incisors through bracket positioning and corresponding consumption of the interdental spaces were measured using coordinate measuring machine. Study revealed that increase in maxillary incisor crown angulation by 1o results in consumption of approximately 0.012 mm of arch perimeter. Similarly, there is a consumption of 0.021 mm of arch perimeter with each degree increase in labial crown inclination. The knowledge of the space implication can be included in the space analysis during the orthodontic treatment planning. Depending upon the amount of space discrepancy, an accurate degree of required alteration in the axial relation of one or more teeth can be planned.

Effect of Crown Angulation of Maxillary Incisor on Effective Arch Perimeter

PubMed Central

Vyas, Matrishva; Singh, Johar Rajvinder

2017-01-01

Introduction It has been postulated that crown angulation and inclination has potential space implication within the arch. With the insight of space implication of the axial relations of teeth, cases of genuine tooth size discrepancies can be dealt with improved stability. Aim This in vitro study was designed to investigate and quantify the influence of angulation and inclination of maxillary incisors on the effective arch perimeter. Materials and Methods Acrylic teeth were arranged over typhodont frame with spaced maxillary anterior segment. Known value of tip and torque in increments were incorporated to maxillary incisors through bracket positioning and corresponding consumption of the interdental spaces were measured using coordinate measuring machine. Results Study revealed that increase in maxillary incisor crown angulation by 1o results in consumption of approximately 0.012 mm of arch perimeter. Similarly, there is a consumption of 0.021 mm of arch perimeter with each degree increase in labial crown inclination. Conclusion The knowledge of the space implication can be included in the space analysis during the orthodontic treatment planning. Depending upon the amount of space discrepancy, an accurate degree of required alteration in the axial relation of one or more teeth can be planned. PMID:28764302

Transition-Metal Derivatives of a Functionalized Cyclopentadienyl Ligand. 15. Synthesis and Structures of Amino Cyclopentadienyl Derivatives of Rhodium(I) and Rhodium(III) Including Water-Soluble Compounds.

PubMed

Philippopoulos, Athanassios I.; Hadjiliadis, Nick; Hart, Claire E.; Donnadieu, Bruno; Mc Gowan, Patrick C.; Poilblanc, René

1997-04-23

The synthesis of monometallic rhodium(III) and rhodium(I) derivatives of dialkylamino-functionalized cyclopentadienyl using the corresponding cyclopentadiene as starting material is facilitated by the presence of the basic amino group. This procedure affords the chloro salts of the substituted rhodicinium cation [(eta(5)-C(5)H(4)(CH(2))(2)NMe(2)H)(2)Rh(III)](3+) ([1][Cl](3)) from the reaction of the [2-(dimethylamino)ethyl]cyclopentadiene with Na(3)Rh(III)Cl(6). 12H(2)O. Similarly the cationic half-sandwich complexes [(eta(5)-C(5)H(4)(CH(2))(n)()NMe(2)H)Rh(I)(cod)](+) (n = 2, [2][Cl], n = 3, [5][Cl]) are obtained from the reaction of the corresponding dialkylamino cyclopentadiene with [RhCl(cod)](2). These types of cationic complexes, 1, 2, and 5, bear pendant ammonium groups. The most classical procedure, starting from the lithium or more efficiently from the sodium cyclopentadienide salt, was used to synthesize neutral complexes [(eta(5)-C(5)H(4)(CH(2))(n)()NMe(2))Rh(I)(cod)] (n = 2, 3; n = 3, 4). The structure of the chloride bis(hexafluorophosphate) salt, [(eta(5)-C(5)H(4)(CH(2))(2)NMe(2)H)(2)Rh(III)](3+)(Cl(-))(PF(6)(-))(2), ([1][Cl][PF(6)](2)) was solved in the triclinic space group P&onemacr; with one molecule in the unit cell, the dimensions of which are a = 6.617(2) Å, b= 7.436(2) Å, c = 13.965(3) Å, alpha = 76.39(2) degrees, beta = 82.31(3) degrees, gamma = 87.26(2) degrees, and V = 661.8(3) Å(3). The noncentrosymmetric character of this solid is attributed to the chloride ion. The tetrafluoroborate salt [(eta(5)-C(5)H(4)(CH(2))(2)NMe(2)H)Rh(I)(cod)](+)(BF(4)(-)) ([2][BF(4)]) crystallizes in the tetragonal space group P4(2)/n with eight molecules in the unit cell, the dimensions of which are a= 21.183(2) Å, b = 21.179(3) Å, c= 8.324(2) Å, and V = 3734(1) Å(3). Least squares refinement leads to values for the conventional R index of [1][Cl][PF(6)](2) (0.0484 for 2191 reflections used) and of [2][BF(4)] (0.0525 for 1083 reflections used); in both cases I > 3sigma(I). As expected, compounds like [2][Cl](3,) [1][Cl][PF(6)](2), [2][Cl], [2][BF(4)], [5][Cl], and [5][BF(4)] are soluble in water.

Performance, static stability, and control effectiveness of a parametric space shuttle launch vehicle

NASA Technical Reports Server (NTRS)

Buchholz, R. E.; Gamble, M.

1972-01-01

This test was run as a continuation of a prior investigation of aerodynamic performance and static stability tests for a parametric space shuttle launch vehicle. The purposes of this test were: (1) to obtain a more complete set of data in the transonic flight region, (2) to investigate new H-0 tank noseshapes and tank diameters, (3) to obtain control effectiveness data for the orbiter at 0 degree incidence and with a smaller diameter H-0 tank, and (4) to determine the effects of varying solid rocket motor-to-H0 tank gap size. Experimental data were obtained for angles of attack from -10 to +10 degrees and for angles of sideslip from +10 to -10 degrees at Mach numbers ranging from .6 to 4.96.

KSC-2012-6322

NASA Image and Video Library

2012-11-28

CAPE CANAVERAL, Fla. – The prototype reactor researchers have begun working with to refine what is needed for a space-ready trash-to-gas device. Designers will reduce the weight and size of the machine so it can take up as little room as possible in a spacecraft. A group of six researchers at Kennedy and groups from NASA centers in Ohio, California and Texas wrote in a recent paper that the current methods of handling trash – either carrying it along on the round trip through space or gathering it into an expendable module and burning it up in Earth's atmosphere – are not suitable answers for missions that go beyond Earth orbit or even past the moon. Working in a laboratory at Kennedy, Hintze's team built an 80-pound device that looks like a three-foot-long metal pipe to test theories about incinerating a variety of trash ranging from used clothes to uneaten food. The reactor holds more than three quarts of material and burns at about 1,000 degrees F, about twice the maximum temperature of an average household oven. It's expected to take astronauts four hours to burn a day's worth of trash from a crew of four. During the course of a year in space – one half the length of time a mission to Mars is expected to take – trash processing for a crew of four would create about 2,200 pounds of methane fuel, enough to power a launch from the lunar surface, Hintze said. Photo credit: NASA/Dmitri Gerondidakis

Finding Space for Participation: Fisherfolk Mobility and Co-Management of Lake Victoria Fisheries

NASA Astrophysics Data System (ADS)

Nunan, Fiona; Luomba, Joseph; Lwenya, Caroline; Yongo, Ernest; Odongkara, Konstantine; Ntambi, Baker

2012-08-01

The literature on fisheries co-management is almost silent on the issue of the movement of fisherfolk within fisheries, although such movement must have implications for the effectiveness of co-management. The introduction of co-management often involves the formation of new structures that should enable the participation of key stakeholder groups in decision-making and management, but such participation is challenging for migrating fishers. The article reports on a study on Lake Victoria, East Africa, which investigated the extent of movement around the lake and the implications of movement for how fishers participate and are represented in co-management, and the implications of the extent and nature of movement for co-management structures and processes. The analysis draws on the concept of space from the literature on participation in development and on a framework of representation in fisheries co-management in addressing these questions. The created space is on an `invited' rather than open basis, reflecting the top-down nature of implementation and the desire to secure participation of different occupational groups, as well as women in a male-dominated sector. The more powerful boat owners dominate positions of power within the co-management system, particularly as the levels of co-management, from sub-district to national, are traversed. The limited power and resources of boat crew are exacerbated by the degree and nature of movement around the lake, making effective participation in co-management decision-making a challenge.

EEG source space analysis of the supervised factor analytic approach for the classification of multi-directional arm movement

NASA Astrophysics Data System (ADS)

Shenoy Handiru, Vikram; Vinod, A. P.; Guan, Cuntai

2017-08-01

Objective. In electroencephalography (EEG)-based brain-computer interface (BCI) systems for motor control tasks the conventional practice is to decode motor intentions by using scalp EEG. However, scalp EEG only reveals certain limited information about the complex tasks of movement with a higher degree of freedom. Therefore, our objective is to investigate the effectiveness of source-space EEG in extracting relevant features that discriminate arm movement in multiple directions. Approach. We have proposed a novel feature extraction algorithm based on supervised factor analysis that models the data from source-space EEG. To this end, we computed the features from the source dipoles confined to Brodmann areas of interest (BA4a, BA4p and BA6). Further, we embedded class-wise labels of multi-direction (multi-class) source-space EEG to an unsupervised factor analysis to make it into a supervised learning method. Main Results. Our approach provided an average decoding accuracy of 71% for the classification of hand movement in four orthogonal directions, that is significantly higher (>10%) than the classification accuracy obtained using state-of-the-art spatial pattern features in sensor space. Also, the group analysis on the spectral characteristics of source-space EEG indicates that the slow cortical potentials from a set of cortical source dipoles reveal discriminative information regarding the movement parameter, direction. Significance. This study presents evidence that low-frequency components in the source space play an important role in movement kinematics, and thus it may lead to new strategies for BCI-based neurorehabilitation.

Exactly solvable quantum cosmologies from two killing field reductions of general relativity

NASA Astrophysics Data System (ADS)

Husain, Viqar; Smolin, Lee

1989-11-01

An exact and, possibly, general solution to the quantum constraints is given for the sector of general relativity containing cosmological solutions with two space-like, commuting, Killing fields. The dynamics of these model space-times, which are known as Gowdy space-times, is formulated in terms of Ashtekar's new variables. The quantization is done by using the recently introduced self-dual and loop representations. On the classical phase space we find four explicit physical observables, or constants of motion, which generate a GL(2) symmetry group on the space of solutions. In the loop representations we find that a complete description of the physical state space, consisting of the simultaneous solutions to all of the constraints, is given in terms of the equivalence classes, under Diff(S1), of a pair of densities on the circle. These play the same role that the link classes play in the loop representation solution to the full 3+1 theory. An infinite dimensional algebra of physical observables is found on the physical state space, which is a GL(2) loop algebra. In addition, by freezing the local degrees of freedom of the model, we find a finite dimensional quantum system which describes a set of degenerate quantum cosmologies on T3 in which the length of one of the S1's has gone to zero, while the area of the remaining S1×S1 is quantized in units of the Planck area. The quantum kinematics of this sector of the model is identical to that of a one-plaquette SU(2) lattice gauge theory.

Crystal structure of ilyukhinite, a new mineral of the eudialyte group

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

Rastsvetaeva, R. K., E-mail: rast@crys.ras.ru; Rozenberg, K. A.; Chukanov, N. V.

The crystal structure of ilyukhinite, a new mineral of the eudialyte group, is studied by X-ray diffraction. The mineral found in pegmatite bodies of the Kukisvumchorr Mountain (Khibiny alkaline complex) is characterized by low sodium content, high degree of hydration, and predominance of manganese over iron. The trigonal cell has the following parameters: a = 14.1695(6) and c = 31.026(1) Å; space group R3m. The structure is refined to final R = 0.046 in the anisotropic approximation of atomic displacements using 1527F > 3σF. The idealized formula of ilyukhinite (Z = 3) is written as (H{sub 3}O,Na){sub 14}Ca{sub 6}Mn{sub 2}Zr{submore » 3}Si{sub 26}O{sub 72}(OH){sub 2} · 3H{sub 2}O. The new mineral differs from other representatives of the eudialyte group by the predominance of both oxonium in the N positions of extra-framework cations and manganese in the Ðœ2 position centering the tetragonal pyramid.« less

Jewelry Design

NASA Technical Reports Server (NTRS)

1987-01-01

A jeweler's torch generates temperatures of 1,400 - 1,800 degrees. Asbestos blocks were used as soldering bases but they were disintegrating at high temperatures. Space Shuttle tiles, manufactured by Lockheed Missiles & Space Co., offered a base with temperature resistance far beyond his requirements.

Dynamics of Axially Symmetric Perturbed Hamiltonians in 1:1:1 Resonance

NASA Astrophysics Data System (ADS)

Carrasco, D.; Palacián, J. F.; Vidal, C.; Vidarte, J.; Yanguas, P.

2018-03-01

We study the dynamics of a family of perturbed three-degree-of-freedom Hamiltonian systems which are in 1:1:1 resonance. The perturbation consists of axially symmetric cubic and quartic arbitrary polynomials. Our analysis is performed by normalisation, reduction and KAM techniques. Firstly, the system is reduced by the axial symmetry, and then, periodic solutions and KAM 3-tori of the full system are determined from the relative equilibria. Next, the oscillator symmetry is extended by normalisation up to terms of degree 4 in rectangular coordinates; after truncation of higher orders and reduction to the orbit space, some relative equilibria are established and periodic solutions and KAM 3-tori of the original system are obtained. As a third step, the reduction in the two symmetries leads to a one-degree-of-freedom system that is completely analysed in the twice reduced space. All the relative equilibria together with the stability and parametric bifurcations are determined. Moreover, the invariant 2-tori (related to the critical points of the twice reduced space), some periodic solutions and the KAM 3-tori, all corresponding to the full system, are established. Additionally, the bifurcations of equilibria occurring in the twice reduced space are reconstructed as quasi-periodic bifurcations involving 2-tori and periodic solutions of the full system.

James Webb Space telescope optical simulation testbed: experimental results with linear control alignment

NASA Astrophysics Data System (ADS)

Egron, Sylvain; Lajoie, Charles-Philippe; Michau, Vincent; Bonnefois, Aurélie; Escolle, Clément; Leboulleux, Lucie; N'Diaye, Mamadou; Pueyo, Laurent; Choquet, Elodie; Perrin, Marshall D.; Ygouf, Marie; Fusco, Thierry; Ferrari, Marc; Hugot, Emmanuel; Soummer, Rémi

2017-09-01

The current generation of terrestrial telescopes has large enough primary mirror diameters that active optical control based on wavefront sensing is necessary. Similarly, in space, while the Hubble Space Telescope (HST) has a mostly passive optical design, apart from focus control, its successor the James Webb Space Telescope (JWST) has active control of many degrees of freedom in its primary and secondary mirrors.

24 CFR 3280.804 - Disconnecting means and branch-circuit protective equipment.

Code of Federal Regulations, 2013 CFR

2013-04-01

... the blank space. (k) When a home is provided with installed service equipment, a single disconnecting... closet entry if the location is such that a clear space of 6 inches to easily ignitable materials is... its full open position (at least 90 degrees). A clear working space at least 30 inches wide and 30...

24 CFR 3280.804 - Disconnecting means and branch-circuit protective equipment.

Code of Federal Regulations, 2012 CFR

2012-04-01

... the blank space. (k) When a home is provided with installed service equipment, a single disconnecting... closet entry if the location is such that a clear space of 6 inches to easily ignitable materials is... its full open position (at least 90 degrees). A clear working space at least 30 inches wide and 30...

Ascending Bloom's Pyramid: Fostering Student Creativity and Innovation in Academic Library Spaces

ERIC Educational Resources Information Center

Bieraugel, Mark; Neill, Stern

2017-01-01

Our research examined the degree to which behaviors and learning associated with creativity and innovation were supported in five academic library spaces and three other spaces at a mid-sized university. Based on survey data from 226 students, we apply a number of statistical techniques to measure student perceptions of the types of learning and…

Teacher Interactions within the Physical Environment: How Teachers Alter Their Space and/or Routines Because of Classroom Character.

ERIC Educational Resources Information Center

Lang, Dale Christopher

Through questionnaires, observations, and interviews, this study revealed the degree to which 31 high school teachers altered their classroom spaces and/or adjusted their routines to meet their pedagogical goals at a temporary school site. Teachers emphatically desired: (1) an appropriate amount of space to rearrange student furniture, enabling…

The Incidence of Allergic Disorders in First Degree Relatives of Neonates with Transient Tachypnea of Neonate

PubMed Central

Basiri, Behnaz; Ghaeeni, Mehdi

2015-01-01

Background The role of maternal allergic disorders to increase the risk of Transient Tachypnea of Neonate (TTN) in neonates remained unclear. We determined the incidence of allergic disorders in first degree relatives of neonates suffered from TTN to clear role of these allergic disorders to predispose TTN in neonates. Materials and Methods In a cross-sectional study carried out at Fatemieh hospital between September 2010 and September 2011, all consecutive neonates with the diagnosis of TTN were included into the study. Those neonates were not treated after 5 days of hospitalization were excluded. Baseline information with regard to the history of allergic diseases among first degree relatives of neonates were charted from family members using a structured questionnaire at enrolment by interviewing and examination if required. Results The two groups were matched for baseline data including neonate gender, birth weight, and type of delivery. In the TTN group, one of first degree relatives (2.9%) suffered from bronchial asthma and two of them (5.7) had atopic dermatitis. In total, allergic diseases was revealed in 8.6% of first degree relatives of neonates with TTN. Besides, none of the first degree relatives of neonates in healthy neonates group experienced bronchial asthma or atopic dermatitis. Allergic rhinitis was not also found in the relatives of the two study neonates groups. Comparing incidence of allergic diseases in first degree relatives of neonates in TTN and healthy groups showed no significant difference (8.6% in TTN group versus 0.0% in healthy group, p = 0.076). Conclusion Our study showed that the incidence of allergic disorders in first degree relatives of neonates suffered from TTN is higher than healthy newborns, but these differences are not statistically significant. PMID:26436012

Determination of Interlaminar Toughness of IM7/977-2 Composites at Temperature Extremes and Different Thicknesses

NASA Technical Reports Server (NTRS)

Johnson, W. S.; Pavlick, M. M.; Oliver, M. S.

2005-01-01

Composite materials are being used in the aerospace industry as a means of reducing vehicle weight. In particular, polymer matrix composites (PMC) are good candidates due to their high strength-to-weight and high stiffness-to-weight ratios. Future reusable space launch vehicles and space exploration structures will need advanced light weight composites in order to minimize vehicle weight while demonstrating robustness and durability, guaranteeing high factors of safety. In particular, the implementation of composite cryogenic propellant fuel tanks (cryotanks) for future reusable launch vehicles (RLVs) could greatly reduce the vehicle's weight versus identically sized cryotanks constructed of metallic materials. One candidate composite material for future cryotank designs is IM7/977-2, which is a graphite/epoxy system. A successful candidate must demonstrate reasonable structural properties over a wide range of temperatures. Since the matrix material is normally the weak link in the composite, tests that emphasize matrix-dominated behavior need to be conducted. Therefore, the objective of this work is to determine the mode I interlaminar fracture toughness of "unidirectional" 8-ply and 16-ply IM7/977-2 through experimental testing. Tests were performed at -196 degrees Celsius (-320 degrees Fahrenheit), 22 degrees Celsius (72 degrees Fahrenheit), 93 degrees Celsius (200 degrees Fahrenheit) and 160 degrees C (320 degrees Fahrenheit). Low temperature testing was completed while the specimen was submerged in a liquid nitrogen bath. High temperature testing was completed in a temperature-controlled oven.

[Correlation analysis of bone marrow edema degree and serum inflammatory factors change with knee joint pain symptoms in patients with bone contusion around the knee joint].

PubMed

Li, Songiun; An, Rongze; Wang, Zhaojie; Kuang, Lipeng; Tan, Weiyuan; Fang, Cunxun

2014-05-01

To explore the correlation between the degree of bone marrow edema (BME) and the content change of tumor necrosis factor alpha (TNF-alpha) and matrix metalloproteinase 3 (MMP-3) and the knee pain symptoms in patients with bone contusion around the knee joint. Thirty patients (30 knees) of bone contusion around the knee joint were chosen as the trial group between October 2009 and April 2012. According to visual analogue scale (VAS), 30 patients were divided into mild group (10 cases), moderate group (10 cases), and severe group (10 cases); according to MRI morphological changes, the patients were divided into type I group (12 cases), type II group (11 cases), and type III group (7 cases). Ten patients (10 knees) with soft tissue injury of the knee were chosen as control group. No significant difference was found (P > 0.05) in gender, age, causes, side, and admission time after injury between 2 groups. The serum contents of MMP-3 and TNF-alpha were detected and statistically analysed between different degrees of pain groups and between different degrees of BME groups. Correlation was analysed between BME and inflammatory factor changes and VAS score. The MMP-3 and TNF-alpha contents in trial group [(29.580 +/- 6.870) (microg/L and (23.750 +/- 7.096) ng/L] were significantly higher than those in control group [(8.219 +/- 1.355) microg/L and (6.485 +/- 1.168) ng/L] (t = 9.686, P = 0.000; t = 7.596, P =0.000). The MMP-3 and TNF-alpha contents in patients with different degrees of pain and BME were significantly higher than those in patients of control group (P < 0.05), and significant difference was found between patients with different degrees of pain (P < 0.05), but no significant difference between patients with different degrees of BME (P > 0.05). Multiple linear regression analysis showed that TNF-alpha content was significantly correlated with VAS score (P = 0.000). Knee pain symptoms are not related to the degree of BME in patients with bone contusion around the knee joint. Inflammatory factor TNF-alpha content is the main influence factor of knee joint pain symptoms.

Cloning, purification, crystallization and preliminary X-ray crystallographic analysis of MCAT from Staphylococcus aureus.

PubMed

Hong, Seung Kon; Kim, Kook Han; Kim, Eunice EunKyeong

2010-01-01

Malonyl-CoA:acyl-carrier protein transacylase (MCAT), encoded by the fabd gene, is a key enzyme in type II fatty-acid biosynthesis. It is responsible for transferring the malonyl group from malonyl-CoA to the holo acyl-carrier protein (ACP). Since the type II system differs from the type I system that mammals use, it has received enormous attention as a possible antibiotic target. In particular, only a single isoform of MCAT has been reported and a continuous coupled enzyme assay has been developed. MCAT from Staphylococcus aureus was overexpressed in Escherichia coli and the protein was purified and crystallized. Diffraction data were collected to 1.2 A resolution. The crystals belonged to space group P2(1), with unit-cell parameters a = 41.608, b = 86.717, c = 43.163 A, alpha = gamma = 90, beta = 106.330 degrees . The asymmetric unit contains one SaMCAT molecule.

[Establishment of heat acclimatization model in rabbits and its pathophysiological characteristics].

PubMed

Wang, Tao; Wang, Jing; Wang, Shang; Li, Pei-Yao; Zhang, Wen-Cheng; Zhao, Xiao-Ling; Wang, Hai

2013-09-01

To establish an effective and stable rabbit heat acclimatization model for the experiment of heat acclimatization mechanisms. Sixteen healthy male rabbits were divided into heat acclimatization group and control group randomly (n = 8). Heat acclimatization (HA) group was kept in simulation chamber with dry bulb temperature of (36 +/- 1) degrees C, wet bulb temperature of (29 +/- 0.5) degrees C, black-bulb temperature of (40 +/- 1.0) degrees C, 100 min/day for 21 days. Control group was kept in the room with temperature of 20 degrees C and relative humidity < 60% during 20 days, then removed into simulation chamber on day 21 to estimate and monitor the rectal temperature together with the heat acclimatization group. Venous blood of control and heat acclimatization group before and after heat exposure on the 1st day, 11th day and 21st day were collected to detect levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6) and heat shock protein 70 (HSP70) by ELISA analysis. (1) Rectal temperature: There was no significant change in control group during 21 days. In heat acclimatization group, it increased (2.07 +/- 0.43) degrees C after the 1st exposure, and increased (1.78 +/- 0.37) degrees C after the 11th exposure, the range of increasing decreased (0.29 +/- 0.09) degrees C. After the 21st exposure, it increased (1.52 +/- 0.29) degrees C, which was (0.55 +/- 0.14) degrees C lower than that of the 1st (P < 0.05),and (0.53 +/- 0.14) degrees C lower to that of the control group under 1st heat stress (P < 0.05); (2) The level of TNF-alpha after the 1st exposure increased significantly (P < 0.05), but didn't raise along with the exposure times. And fell back to the original level after the 11th and 21st exposure. Compared with control group, the level of IL-6 increased after the 1st, 11th and 21st exposure (P < 0.05), and maintained highly after the 11th and 21st exposure. Compared with the control group, the level of HSP70 increased dramatically with the heat exposure times. Significant increasing of (HSP70) could be detected after the 11th and 21st exposure (P < 0.05), but there was no difference to that of the 1st exposure. Prolonged or repeated exposure to heat stressful environmental conditions can reduce the physiological strain, improve heat tolerance, elicits heat acclimatization.

Reentry aerodynamic characteristics of a space shuttle solid rocket booster model 449 tested in MSFC 14 by 14 inch TWT (SA26F)

NASA Technical Reports Server (NTRS)

Johnson, J. D.; Braddock, W. F.

1974-01-01

Force tests of a 0.563 percent scale space shuttle solid rocket booster (SRB) model, MSFC Model 449, were conducted at the Marshall Space Flight Center 14 x 14 inch Trisonic Wind Tunnel. There were a total of 134 runs (pitch polars) made. Test Mach numbers were 0.6, 0.9, 1.2, 1.96, 2.74, 3.48, 4.00, 4.45, and 4.96; test angles of attack ranged from minus 10 degrees to 190 degrees; test Reynolds numbers ranged from 4.9 million per foot to 7.1 million per foot; and test roll angles were 0, 45, 90, and 135 degrees. The model was tested with three different engine nozzle/skirts. Two of these engine configurations differed from each other in the magnitude of the volume inside the nozzle and skirt. The third engine configuration had part of the nozzle removed. The model was tested with an electrical tunnel in combination with separation rockets of two different heights.

Effects of early heat exposure on thermoregulatory responses and blood viscosity of broilers prior to marketing.

PubMed

Zhou, W T; Fujita, M; Ito, T; Yamamoto, S

1997-07-01

1. This study was to determine the effects of heat load early in life on thermoregulatory responses and whole blood viscosity of broilers during a subsequent exposure to high environmental temperature later in life. 2. The birds, which had been subjected to exposure to 38 degrees C for 24 h at 5-d-old, served as prior exposure group (group A). Both group A and control group B were exposed to 33 degrees C for 3 h when near marketable weight. 3. On exposure to 33 degrees C, although there were no significant differences in the increases in heat production (HP) between the two groups, abdominal temperature (Ta), temperature of external ear tract (Tee), shank skin temperature (Tss), standing-lying frequency and lying time were lower in group A than in group B. Heart rate (HR) and comb surface temperature (Tcs) did not differ but increased in both groups during exposure to 33 degrees C. Respiration rate (RR) was greater in group A. 4. Blood viscosity decreased markedly in both groups after exposure to 33 degrees C; the decrease was greater in group A. 5. These results suggest that early exposure may promote broilers' ability to cope with the subsequent heat load by altering thermoregulatory physiological responses and behavioural patterns, resulting in an alleviation of heat stress.

A six degree-of-freedom Lorentz vibration isolator with nonlinear controller

NASA Astrophysics Data System (ADS)

Fenn, Ralph C.

1992-05-01

The results of a phase 2 Small Business Innovation Research Program sponsored by MSFC are presented. Technology is developed for isolating acceleration sensitive microgravity experiments from structural vibration of a spacecraft, such as a space station. Two hardware articles are constructed: a six degree of freedom Lorentz force isolation and a one degree of freedom low acceleration testbed capable of tests at typical experiment accelerations.

Interference between Space and Time Estimations: From Behavior to Neurons.

PubMed

Marcos, Encarni; Genovesio, Aldo

2017-01-01

Influences between time and space can be found in our daily life in which we are surrounded by numerous spatial metaphors to refer to time. For instance, when we move files from one folder to another in our computer a horizontal line that grows from left to right informs us about the elapsed and remaining time to finish the procedure and, similarly, in our communication we use several spatial terms to refer to time. Although with some differences in the degree of interference, not only space has an influence on time but both magnitudes influence each other. Indeed, since our childhood our estimations of time are influenced by space even when space should be irrelevant and the same occurs when estimating space with time as distractor. Such interference between magnitudes has also been observed in monkeys even if they do not use language or computers, suggesting that the two magnitudes are tightly coupled beyond communication and technology. Imaging and lesion studies have indicated that same brain areas are involved during the processing of both magnitudes and have suggested that rather than coding the specific magnitude itself the brain represents them as abstract concepts. Recent neurophysiological studies in prefrontal cortex, however, have shown that the coding of absolute and relative space and time in this area is realized by independent groups of neurons. Interestingly, instead, a high overlap was observed in this same area in the coding of goal choices across tasks. These results suggest that rather than during perception or estimation of space and time the interference between the two magnitudes might occur, at least in the prefrontal cortex, in a subsequent phase in which the goal has to be chosen or the response provided.

User interfaces in space science instrumentation

NASA Astrophysics Data System (ADS)

McCalden, Alec John

This thesis examines user interaction with instrumentation in the specific context of space science. It gathers together existing practice in machine interfaces with a look at potential future usage and recommends a new approach to space science projects with the intention of maximising their science return. It first takes a historical perspective on user interfaces and ways of defining and measuring the science return of a space instrument. Choices of research methodology are considered. Implementation details such as the concepts of usability, mental models, affordance and presentation of information are described, and examples of existing interfaces in space science are given. A set of parameters for use in analysing and synthesizing a user interface is derived by using a set of case studies of diverse failures and from previous work. A general space science user analysis is made by looking at typical practice, and an interview plus persona technique is used to group users with interface designs. An examination is made of designs in the field of astronomical instrumentation interfaces, showing the evolution of current concepts and including ideas capable of sustaining progress in the future. The parameters developed earlier are then tested against several established interfaces in the space science context to give a degree of confidence in their use. The concept of a simulator that is used to guide the development of an instrument over the whole lifecycle is described, and the idea is proposed that better instrumentation would result from more efficient use of the resources available. The previous ideas in this thesis are then brought together to describe a proposed new approach to a typical development programme, with an emphasis on user interaction. The conclusion shows that there is significant room for improvement in the science return from space instrumentation by attention to the user interface.

One-step formation of straight nanostripes from a mammal lipid-oleamide directly on highly oriented pyrolytic graphite.

PubMed

Zhang, Renjie; Möhwald, Helmuth; Kurth, Dirk G

2009-02-17

Hierarchical nanostructures are obtained directly on highly oriented pyrolytic graphite (HOPG) by spin coating of dilute chloroform solution of 9-Z-octadecenamide (oleamide), a natural lipid with cis-CdC- conformation, existing in the cerebrospinal fluid of mammal animals and being an additive for medical use and food packaging. Straight separated nanostripes with a length of 70-300 nm exist in the topmost layer and compact nanostripes in the bottom layer contacting HOPG. Compact nanostripes have a periodicity spacing of 3.8 nm, indicating H-bonding between two rows of oleamide molecules. The orientation of the hierarchical nanostructures differs by n60 degrees+/-8 degrees (n=1 or 2), reflecting the epitaxial ordering along theHOPGsubstrate. The nanostripes are stable against annealing.Amolecular packing scheme for the nanostructures is proposed, where the -C=C bond angle in oleamide is 120 degrees and the plane of the carbon skeleton lies parallel to the HOPG substrate. Nanostripes in the topmost layer are formed from separated rows of oleamide molecules, due to the short-range surface potential of the substrate. The scheme involves direct influence ofHOPGon the orientation of oleamide molecules to form nanostripes without any purposely added saturated alkanes and H-bonds between amide groups in adjacent two rows of oleamide molecules.

Characterization of high order spatial discretizations and lumping techniques for discontinuous finite element SN transport

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

Maginot, P. G.; Ragusa, J. C.; Morel, J. E.

2013-07-01

We examine several possible methods of mass matrix lumping for discontinuous finite element discrete ordinates transport using a Lagrange interpolatory polynomial trial space. Though positive outflow angular flux is guaranteed with traditional mass matrix lumping in a purely absorbing 1-D slab cell for the linear discontinuous approximation, we show that when used with higher degree interpolatory polynomial trial spaces, traditional lumping does yield strictly positive outflows and does not increase in accuracy with an increase in trial space polynomial degree. As an alternative, we examine methods which are 'self-lumping'. Self-lumping methods yield diagonal mass matrices by using numerical quadrature restrictedmore » to the Lagrange interpolatory points. Using equally-spaced interpolatory points, self-lumping is achieved through the use of closed Newton-Cotes formulas, resulting in strictly positive outflows in pure absorbers for odd power polynomials in 1-D slab geometry. By changing interpolatory points from the traditional equally-spaced points to the quadrature points of the Gauss-Legendre or Lobatto-Gauss-Legendre quadratures, it is possible to generate solution representations with a diagonal mass matrix and a strictly positive outflow for any degree polynomial solution representation in a pure absorber medium in 1-D slab geometry. Further, there is no inherent limit to local truncation error order of accuracy when using interpolatory points that correspond to the quadrature points of high order accuracy numerical quadrature schemes. (authors)« less

Peak-Power Markets for Satellite Solar Power

NASA Astrophysics Data System (ADS)

Landis, G.

2002-01-01

Aman MOSTAVANNobuyuki KAYA Institut Teknologi Bandung (TF)Kobe University, Rokkodai, Nada, Ganesha 10; Bandung 40132, IndonesiaKobe 657, Japan mostavan@tf.itb.ac.idkaya@kobe-u.ac.jp This paper introduces first Indonesia, comprises 15 000 islands, has land area of two millions square kilometers. Extending from 95 to 141 degrees East longitude and from 6 degrees North to 11 degrees South latitude. Further the market of the Space Solar Power/SPS must be worldwide, including Indonesia. As we know, it can provide electricity anywhere in the world from the Earth's orbit, mostly Indonesia an equator country. We have to perform case studies of various countries to understand their benefits and disadvantages provided by the SSP, because each country has much different condition on energy from other countries. We are at the moment starting the international collaboration between Indonesia and Japan to carry out the case study for Indonesia. We understand that in Indonesia itself each province has much different micro-climate between one province compared to the other. In Japan, METI (Ministry of Economy, Trade and Industry) has already organized a committee to investigate the feasibility of Space Solar Power and to make a plan to launch a space demonstration of the SPS. While, Indonesia is quickly developing economy and increasing their energy demand. We are investigating the detailed energy conditions of Indonesia, the benefits and disadvantages of the Space Solar Power for Indonesia. Especially, we will perform the investigation on the receiving system for the Japanese pilot Space Power Satellite.

Are postgraduate qualifications the 'new frontier of social mobility'?

PubMed

Wakeling, Paul; Laurison, Daniel

2017-09-01

We investigate the relationship between social origin, postgraduate degree attainment, and occupational outcomes across five British age-group cohorts. We use recently-available UK Labour Force Survey data to conduct a series of logistic regressions of postgraduate (masters or doctorate) degree attainment among those with first degrees, with controls for measures of degree classification, degree subject, age, gender, ethnicity and national origin. We find a marked strengthening of the effect of class origin on degree- and occupational attainment across age cohorts. While for older generations there is little or no difference by class origin in the rates at which first-degree graduates attain postgraduate degrees, those with working-class-origins in the youngest age-group are only about 28 per cent as likely to obtain a postgraduate degree when compared with their peers from privileged origins. Moreover, social origin matters more for occupational destination, even among those with postgraduate degrees, for those in younger age groups. These findings demonstrate the newly important, and increasing, role of postgraduate degrees in reproducing socio-economic inequality in the wake of the substantial expansion of undergraduate and postgraduate education. Our findings lend some support to the Maximally Maintained Inequality thesis, suggesting that gains in equality of access to first-degrees are indeed at risk from postgraduate expansion. © London School of Economics and Political Science 2017.

Earth observations taken from shuttle orbiter Columbia

NASA Image and Video Library

1995-10-22

STS073-728-010 (22 October 1995) --- Photographed by the astronauts aboard the Space Shuttle Columbia orbiting at 146 nautical miles above Earth is this scene over West Virginia featuring the Appalachian Mountains. Center point coordinates are 37.5 degrees north latitude and 80.5 degrees west longitude.

Coronal leakage inhibition in endodontically treated teeth using resin-coating technique.

PubMed

Maruoka, Rena; Nikaido, Toru; Ikeda, Masaomi; Ishizuka, Tomoyasu; Foxton, Richard M; Tagami, Junji

2006-03-01

The purpose of this study was to evaluate coronal leakage inhibition using a resin-coating technique after endodontic treatment. Thirty-six human incisors were cut at the cementoenamel junction, and endodontic obturations were performed. The specimens were randomly divided into three groups according to post space preparation (10 mm depth), resin coating, and temporization. For the resin coating, the dentin surface was coated with either a combination of Clearfil SE Bond and Protect Liner F (SE/PLF) or RZII (RZ). Then, the specimens were stored in 37 degrees C distilled water for 24 hours and placed in 1% methylene blue solution for 48 hours. After which, the specimens were sectioned faciolingually along the root canal and the length of dye penetration was measured from the cementoenamel junction. Three-way ANOVA revealed that the dye penetration scores were influenced by post space preparation, resin coating, and temporization. Resin coating with RZ significantly reduced the dye penetration score and SE/PLF completely eliminated dye penetration.

Using Geographic Information Science to Explore Associations between Air Pollution, Environmental Amenities, and Preterm Births

PubMed Central

Ogneva-Himmelberger, Yelena; Dahlberg, Tyler; Kelly, Kristen; Simas, Tiffany A. Moore

2015-01-01

The study uses geographic information science (GIS) and statistics to find out if there are statistical differences between full term and preterm births to non-Hispanic white, non-Hispanic Black, and Hispanic mothers in their exposure to air pollution and access to environmental amenities (green space and vendors of healthy food) in the second largest city in New England, Worcester, Massachusetts. Proximity to a Toxic Release Inventory site has a statistically significant effect on preterm birth regardless of race. The air-pollution hazard score from the Risk Screening Environmental Indicators Model is also a statistically significant factor when preterm births are categorized into three groups based on the degree of prematurity. Proximity to green space and to a healthy food vendor did not have an effect on preterm births. The study also used cluster analysis and found statistically significant spatial clusters of high preterm birth volume for non-Hispanic white, non-Hispanic Black, and Hispanic mothers. PMID:29546120

Avoiding space robot collisions utilizing the NASA/GSFC tri-mode skin sensor

NASA Technical Reports Server (NTRS)

Prinz, F. B. S.; Mahalingam, S.

1992-01-01

A capacitance based proximity sensor, the 'Capaciflector' (Vranish 92), has been developed at the Goddard Space Flight Center of NASA. We had investigated the use of this sensor for avoiding and maneuvering around unexpected objects (Mahalingam 92). The approach developed there would help in executing collision-free gross motions. Another important aspect of robot motion planning is fine motion planning. Let us classify manipulator robot motion planning into two groups at the task level: gross motion planning and fine motion planning. We use the term 'gross planning' where the major degrees of freedom of the robot execute large motions, for example, the motion of a robot in a pick and place type operation. We use the term 'fine motion' to indicate motions of the robot where the large dofs do not move much, and move far less than the mirror dofs, such as in inserting a peg in a hole. In this report we describe our experiments and experiences in this area.

Using Geographic Information Science to Explore Associations between Air Pollution, Environmental Amenities, and Preterm Births.

PubMed

Ogneva-Himmelberger, Yelena; Dahlberg, Tyler; Kelly, Kristen; Simas, Tiffany A Moore

2015-01-01

The study uses geographic information science (GIS) and statistics to find out if there are statistical differences between full term and preterm births to non-Hispanic white, non-Hispanic Black, and Hispanic mothers in their exposure to air pollution and access to environmental amenities (green space and vendors of healthy food) in the second largest city in New England, Worcester, Massachusetts. Proximity to a Toxic Release Inventory site has a statistically significant effect on preterm birth regardless of race. The air-pollution hazard score from the Risk Screening Environmental Indicators Model is also a statistically significant factor when preterm births are categorized into three groups based on the degree of prematurity. Proximity to green space and to a healthy food vendor did not have an effect on preterm births. The study also used cluster analysis and found statistically significant spatial clusters of high preterm birth volume for non-Hispanic white, non-Hispanic Black, and Hispanic mothers.

Remote Operations of the Deep Space Network Radio Science Subsystem

NASA Astrophysics Data System (ADS)

Caetta, J.; Asmar, S.; Abbate, S.; Connally, M.; Goltz, G.

1998-04-01

The capability for scientists to remotely control systems located at the Deep Space Network facilities only recently has been incorporated in the design and implementation of new equipment. However, time lines for the implementation, distribution, and operational readiness of such systems can extend much farther into the future than the users can wait. The Radio Science Systems Group was faced with just that circumstance; new hardware was not scheduled to become operational for several years, but the increasing number of experiments and configurations for Cassini, Galileo, Mars missions, and other flight projects made that time frame impractical because of the associated increasing risk of not acquiring critical data. Therefore, a method of interfacing with the current radio science subsystem has been developed and used with a high degree of success, although with occasional problems due to this capability not having been originally designed into the system. This article discusses both the method and the problems involved in integrating this new (remote) method of control with a legacy system.

The breeding behaviour, advertisement call and tadpole of Limnonectes dabanus (Anura: Dicroglossidae).

PubMed

Rowley, Jodi J L; Le, Duong Thi Thuy; Hoang, Huy Duc; Altig, Ronald

2014-11-04

Fanged frogs (Limnonectes) are a group of dicroglossid frogs from Asia that often have reversed sexual dimorphism with larger males. Limnonectes dabanus is a poorly known species of fanged frog from forested habitats in southern Vietnam and eastern Cambodia. Adult males exhibit an extreme degree of megacephaly and possess bizarre head ornamentation. L. dabanus breeds in shallow, non-flowing or very slow-flowing pools, puddles, and drainage ditches. Eggs are laid as a widely spaced array, and the larvae have a morphology typical of pond-dwelling tadpoles. Although males of the species lack vocal sacs, they produce a low-pitched (0.4-0.6 kHz), single-note advertisement call that sounds like a drop of water falling into water. Given the spacing of calling males, presence of multiple females near breeding sites, and reversed sexual dimorphism, the mating system of L. dabanus may be an example of resource-defense polygyny, and the massive head of the male is likely used in male combat.

Microgravity promotes osteoclast activity in medaka fish reared at the international space station.

PubMed

Chatani, Masahiro; Mantoku, Akiko; Takeyama, Kazuhiro; Abduweli, Dawud; Sugamori, Yasutaka; Aoki, Kazuhiro; Ohya, Keiichi; Suzuki, Hiromi; Uchida, Satoko; Sakimura, Toru; Kono, Yasushi; Tanigaki, Fumiaki; Shirakawa, Masaki; Takano, Yoshiro; Kudo, Akira

2015-09-21

The bone mineral density (BMD) of astronauts decreases specifically in the weight-bearing sites during spaceflight. It seems that osteoclasts would be affected by a change in gravity; however, the molecular mechanism involved remains unclear. Here, we show that the mineral density of the pharyngeal bone and teeth region of TRAP-GFP/Osterix-DsRed double transgenic medaka fish was decreased and that osteoclasts were activated when the fish were reared for 56 days at the international space station. In addition, electron microscopy observation revealed a low degree of roundness of mitochondria in osteoclasts. In the whole transcriptome analysis, fkbp5 and ddit4 genes were strongly up-regulated in the flight group. The fish were filmed for abnormal behavior; and, interestingly, the medaka tended to become motionless in the late stage of exposure. These results reveal impaired physiological function with a change in mechanical force under microgravity, which impairment was accompanied by osteoclast activation.

Microgravity promotes osteoclast activity in medaka fish reared at the international space station

PubMed Central

Chatani, Masahiro; Mantoku, Akiko; Takeyama, Kazuhiro; Abduweli, Dawud; Sugamori, Yasutaka; Aoki, Kazuhiro; Ohya, Keiichi; Suzuki, Hiromi; Uchida, Satoko; Sakimura, Toru; Kono, Yasushi; Tanigaki, Fumiaki; Shirakawa, Masaki; Takano, Yoshiro; Kudo, Akira

2015-01-01

The bone mineral density (BMD) of astronauts decreases specifically in the weight-bearing sites during spaceflight. It seems that osteoclasts would be affected by a change in gravity; however, the molecular mechanism involved remains unclear. Here, we show that the mineral density of the pharyngeal bone and teeth region of TRAP-GFP/Osterix-DsRed double transgenic medaka fish was decreased and that osteoclasts were activated when the fish were reared for 56 days at the international space station. In addition, electron microscopy observation revealed a low degree of roundness of mitochondria in osteoclasts. In the whole transcriptome analysis, fkbp5 and ddit4 genes were strongly up-regulated in the flight group. The fish were filmed for abnormal behavior; and, interestingly, the medaka tended to become motionless in the late stage of exposure. These results reveal impaired physiological function with a change in mechanical force under microgravity, which impairment was accompanied by osteoclast activation. PMID:26387549

[Relationship between PMP, FN, vWF and Bleeding Degree in Patients with Acute Leukemia].

PubMed

Wang, Chang-Sheng; Zhao, Lian; Huang, Li-Yun; Yue, Xiao-He

2018-06-01

To detect the serum levels of platelet microparticle (PMP), fibronectin (FN), and von Willebrand Factor (vWF) in acute leukemia (AL) patients with thrombocytopenic and to analyze the relationship of the serum levels of PMP, FN and vWF with bleeding degree. One hundred and one newly diagnosed AL patients from May 2014 to May 2017 were enrolled the AL group. According to the WHO standard of bleeding stratification, 101 AL patients were divided into 5 sub groups: 0, 1, 2, 3 and 4 score groups; 52 normal persons subjected to physical examination were enrolled in control group. The PMP level was detected by flow cytometry; the FN and vWF levels were detected by ELISA. The levels of PMP, FN and vWF were compared between the AL group and the control group. The serum levels of PMP, FN and vWF were compared according to bleeding degree group. The relationship of bleeding degree with the serum levels of PMP, FN and vWF was analyzed. The patients with newly diagnosed acute leukemia aged 18 to 60, and accounted for 61.39%. The degree of bleeding was mainly 1 score, which accounted for 38.61%. The serum levels of PMP, vWF and FN AL groups were significantly higher than those in control group (6.06%±4.38% vs 0.89%±0.50%, 205.82±24.89 vs 58.04±13.35 µg/L, 398.29±46.93 vs 311.37±26.02 µg/L)(P<0.001). The serum levels of PMP, FN and vWF were different among 5 subgroup (P<0.01); the level of PMP and FN were the highest in 0 score group and the lowest in 4 score group; the vWF level was the highest in 4 score groups and the lowest in 0 score group. The bleeding degree in the patients with acute leukemia negatively correlated with PMP level, and positively with NF and vWF levels (r=-0.753, r=0.648, r=0.805). According to the relationship of the bleeding degree with serum levels of PMP, FN, vWF in patients, the detection of PMP, vWF and FN levels can help to evaluale the bleeding degree in the patients.

Hamiltonian indices and rational spectral densities

NASA Technical Reports Server (NTRS)

Byrnes, C. I.; Duncan, T. E.

1980-01-01

Several (global) topological properties of various spaces of linear systems, particularly symmetric, lossless, and Hamiltonian systems, and multivariable spectral densities of fixed McMillan degree are announced. The study is motivated by a result asserting that on a connected but not simply connected manifold, it is not possible to find a vector field having a sink as its only critical point. In the scalar case, this is illustrated by showing that only on the space of McMillan degree = /Cauchy index/ = n, scalar transfer functions can one define a globally convergent vector field. This result holds both in discrete-time and for the nonautonomous case. With these motivations in mind, theorems of Bochner and Fogarty are used in showing that spaces of transfer functions defined by symmetry conditions are, in fact, smooth algebraic manifolds.

On the polymorphism of benzocaine; a low-temperature structural phase transition for form (II).

PubMed

Chan, Eric J; Rae, A David; Welberry, T Richard

2009-08-01

A low-temperature structural phase transition has been observed for form (II) of benzocaine (BZC). Lowering the temperature doubles the b-axis repeat and changes the space group from P2(1)2(1)2(1) to P112(1) with gamma now 99.37 degrees. The structure is twinned, the twin rule corresponding to a 2(1) screw rotation parallel to a. The phase transition is associated with a sequential displacement parallel to a of zigzag bi-layers of ribbons perpendicular to b*. No similar phase transition was observed for form (I) and this was attributed to the different packing symmetries of the two room-temperature polymorphic forms.

Relativistic top: An application of the BFV quantization procedure for systems with degenerate constraints

NASA Astrophysics Data System (ADS)

Nielsen, N. K.; Quaade, U. J.

1995-07-01

The physical phase space of the relativistic top, as defined by Hansson and Regge, is expressed in terms of canonical coordinates of the Poincaré group manifold. The system is described in the Hamiltonian formalism by the mass-shell condition and constraints that reduce the number of spin degrees of freedom. The constraints are second class and are modified into a set of first class constraints by adding combinations of gauge-fixing functions. The Batalin-Fradkin-Vilkovisky method is then applied to quantize the system in the path integral formalism in Hamiltonian form. It is finally shown that different gauge choices produce different equivalent forms of the constraints.

Crystallization and preliminary X-ray diffraction analysis of a self-complementary DNA heptacosamer with a 20-base-pair duplex flanked by seven-nucleotide overhangs at the 3'-terminus.

PubMed

Yeo, Hyun Koo; Lee, Jae Young

2010-05-01

The self-complementary DNA heptacosamer (a 27-mer oligonucleotide) with sequence d(CGAGCACTGCGCAGTGCTCGTTGTTAT) forms a 20-base-pair duplex flanked by seven-nucleotide overhangs at the 3'-terminus. Crystals of the oligonucleotide were obtained by sitting-drop vapour diffusion and diffracted to 2.8 A resolution. The oligonucleotide was crystallized at 277 K using polyethylene glycol as a precipitant in the presence of magnesium chloride. The crystals belonged to the triclinic space group, with unit-cell parameters a = 48.74, b = 64.23, c = 79.34 A, alpha = 91.37, beta = 93.21, gamma = 92.35 degrees .

Williams loads the MELFI for the Nutrition Experiment during Expedition 15

NASA Image and Video Library

2007-06-01

ISS015-E-10572 (1 June 2007) --- Astronaut Sunita L. Williams, Expedition 15 flight engineer, inserts test samples in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as a part of the Nutritional Status Assessment (Nutrition) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

Chamitoff works with the MELFI in the U.S. Laboratory during Expedition 17

NASA Image and Video Library

2008-09-27

ISS017-E-017541 (27 Sept. 2008) --- NASA astronaut Greg Chamitoff, Expedition 17 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

Chamitoff works with the MELFI in the U.S. Laboratory during Expedition 17

NASA Image and Video Library

2008-09-27

ISS017-E-017539 (27 Sept. 2008) --- NASA astronaut Greg Chamitoff, Expedition 17 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

Anderson works on the NUTRITION Experiment in the US Lab during Expedition 15

NASA Image and Video Library

2007-06-25

ISS015-E-13670 (25 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

Anderson works on the NUTRITION Experiment in the US Lab during Expedition 15

NASA Image and Video Library

2007-06-25

ISS015-E-13695 (25 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

Space Radar Image of Baikal Lake, Russia

NASA Image and Video Library

1999-05-01

This is an X-band black-and-white image of the forests east of the Baikal Forest in the Jablonowy Mountains of Russia. The image is centered at 52.5 degrees north latitude and 116 degrees east longitude near the mining town of Bukatschatscha. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar aboard the space shuttle Endeavour on October 4, 1994, during the second flight of the spaceborne radar. This area is part of an international research project known as the Taiga Aerospace Investigation using Geographic Information System Applications. http://photojournal.jpl.nasa.gov/catalog/PIA01754

Bar Code Labels

NASA Technical Reports Server (NTRS)

1988-01-01

American Bar Codes, Inc. developed special bar code labels for inventory control of space shuttle parts and other space system components. ABC labels are made in a company-developed anodizing aluminum process and consecutively marketed with bar code symbology and human readable numbers. They offer extreme abrasion resistance and indefinite resistance to ultraviolet radiation, capable of withstanding 700 degree temperatures without deterioration and up to 1400 degrees with special designs. They offer high resistance to salt spray, cleaning fluids and mild acids. ABC is now producing these bar code labels commercially or industrial customers who also need labels to resist harsh environments.

Earth Observations

NASA Image and Video Library

2013-05-18

ISS036-E-002105 (18 May 2013) --- Pavlof Volcano was captured in the fourth day of its eruption by one of the Expedition 36 crew members on the International Space Station. Pavlof volcano, on the Alaskan Peninsula about 625 miles (1,000 kilometers) southwest of Anchorage, jetted lava into the air and spewed an ash cloud 20,000 feet (6,000 meters) high. The space station was above a point in the North Pacific Ocean located at 49.1 degrees north latitude and 157.4 degrees west longitude, about 475 miles south-southeast of the volcano. The volcanic plume extends southeastward. The volcano began erupting May 13.

Earth Observations

NASA Image and Video Library

2013-05-18

ISS036E002106 (18 May 2013) --- Pavlof Volcano was captured in the fourth day of its eruption by one of the Expedition 36 crew members on the International Space Station. Pavlof volcano, onn the Alaskan Peninsula about 625 miles (1,000 kilometers) southwest of Anchorage, jetted lava into the air and spewed an ash cloud 20,000 feet (6,000 meters) high. The space station was above a point in the North Pacific Ocean located at 49.1 degrees north latitude and 157.4 degrees west longitude, about 475 miles south-southeast of the volcano. The volcanic plume extends southeastward. The volcano began erupting May 13.

[Comparison of LCP and locked intramedullary nailing fixation in treatment of tibial diaphysis fractures].

PubMed

Huang, Peng; Tang, Peifu; Yao, Qi

2007-11-01

To evaluate the treatment results of LCP and locked intramedullary nailing for tibial diaphysis fractures. From October 2003 to April 2006, 55 patients with tibial diaphysis fractures (58 fractures) were treated. Of them there were 39 males and 16 females with an average of 39 years years ( 14 to 62 years). The fractures were on the left side in 27 patients and on the right side in 31 patients (3 patients had bilateral involvement). Thirty-four fractures were treated by intramedullary nailing (intramedullary nailing group) and 24 fractures by LCP fixation (LCP group). The average disease course was 3 days (intramedullary nailing group) and 3.1 days (LCP group). The operation time, the range of motion of knee and ankle joints, fracture healing time, and complications were evaluated. The patients were followed up 8-26 months (13 months on average). The operation time was 84.0+/-9.2 min (intramedullary nailing group) and 69.0+/-8.4 min (LCP group); the average cost in hospital was yen 19,297.78 in the intramedullary nailing group and yen 14,116.55 in the LCP group respectively, showing significant differences (P < 0.05). The flexion and extension of knee joint was 139.0 +/- 3.7 degrees and 4.0 +/- 0.7 degrees in intramedullary nailing group and 149.0+/-4.2 degrees and 0+/-0.4 degrees in LCP group, showing no significant difference (P>0.05). The doral flexion and plantar flexion of ankle joint were 13.0+/-1.7 degrees and 41.0+/-2.6 degrees in intramedullary nailing group, and 10.0+/-1.4 degrees and 44.0+/-2.3 degrees in LCP group, showing no significant differences (P>0.05). The mean healing time was 3.3 months in intramedullary nailing group, and 3. 1 months in LCP group. Length discrepancy occurred in 1 case (2.5 cm), delayed union in 1 case and nailing end trouble in 3 cases in intramedullary nailing group; moreover rotation deformity occurred 1 case and anterior knee pain occurred in 6 cases (17.1%). One angulation and open fracture developed osteomyelitis in 1 case 1 week postoperatively and angulation deformity occurred in 1 case of distal-third tibial fractures in LCP group. LCP and locked intramedullary nailing can achieve satisfactory results in treating tibial diaphysis fracture LCP has advantages in less complication, operation time and cost in hospital.

Diary of an astronaut: examination of the remains of the late Israeli astronaut Colonel Ilan Ramon's Crew Notebook recovered after the loss of NASA's space shuttle Columbia.

PubMed

Brown, Sharon; Sin-David, Laser

2007-05-01

Two months after the fatal re-entering into the Earth's atmosphere of Columbia flight STS-107, the remains of Israeli astronaut Colonel Ilan Ramon's Crew Notebook were found strewn in a field in San Augustine County, TX. The random pile of papers was found to have survived the calamity of the Shuttle's disintegration remarkably well. Most of the papers recovered were torn and/or washed out to varying degrees but only mildly charred around the edges. The sheets of paper could be categorized into four groups: Group I: eight sides of paper written while in space in black ink and in pencil--Ramon's personal diary; the writing on these eight sides of paper survived well and is only missing where the pages were torn. Small fragments found in the field were physically matched to holes in the pages thus locating their original positions in the text. Group II: six sides of technical preparation notes written by Ramon before the mission. The writing on these pages was washed out entirely, but much of it was visualized using infrared luminescence. Group III: eight sides of personal notes prepared by Ramon before the mission written in blue ink. The writing on these pages was barely visible to the naked eye and not visualized by infrared luminescence, but was made largely legible by digital enhancement imaging. Group IV: a few sides of printed technical information. These pages were mostly intact and were not examined at length as they contained standard printed material. After completion of examinations at the Questioned Document Laboratory of the Israel Police, the diary was transferred to the Paper Conservation Department of the Israel Museum for preservation and strengthening treatments.

Examining the Impact of Adherence to a Vegan Diet on Acid-Base Balance in Healthy Adults.

PubMed

Cosgrove, Kelly; Johnston, Carol S

2017-09-01

Acidogenic diets, commonly measured by the potential renal acid load (PRAL), have been linked with metabolic diseases including insulin resistance, hepatic dysfunction, and cardiometabolic risk. Vegan diets are linked to low dietary acid loads, but the degree of adherence to a vegan diet to demonstrate this benefit is unknown. This study compared the change in PRAL and urine pH of omnivores who followed a vegan diet for either 2, 3, or 7 days over one week. Healthy adults were recruited from a campus population and randomly assigned to one of the three groups: VEG7 (vegan diet followed for seven consecutive days); VEG3 (vegan diet followed for three evenly spaced days over one week); or VEG2 (vegan diet followed for two evenly spaced days over one week). Gender, age, and body mass index did not differ between groups (overall: 21.8 ± 2.4 y and 24.4 ± 5.6 kg/m 2 ). Following the one week intervention, outcome measures did not vary between the VEG2 and VEG3 groups, and these groups were collapsed for the final analyses. The 24-h urine pH was raised after seven consistent days of vegan diet adherence and was unchanged after 2-3 days of vegan diet adherence over the course of a week (+0.52 ± 0.69 and -0.02 ± 0.56 respectively, p = 0.048). However, dietary PRAL scores fell significantly in both dietary groups during the 7-day trial. Since low dietary PRAL scores have been related to improve metabolic parameters, adoption of a vegan diets for several days per week should be explored as a diet strategy to lower disease risk.

Earth Observations taken by the Expedition 17 Crew

NASA Image and Video Library

2008-04-30

ISS017-E-005751 (30 April 2008) --- When this image was photographed by one of the crew members aboard the International Space Station, Tropical Cyclone Nargis was centered near a point located at 15.3 degrees north latitude and 88.2 degrees north longitude and moving northeast at 065 degrees at 8.1 miles per hour. The center was approximately 7 degrees southwest of Burma with sustained winds of 74.9 miles per hour, gusting to 92.2 miles per hour, forecast to strengthen. Maximum significant wave height was 27 feet.

Earth Observations taken by the Expedition 17 Crew

NASA Image and Video Library

2008-04-30

ISS017-E-005749 (30 April 2008) --- When this image was photographed by one of the crew members aboard the International Space Station, Tropical Cyclone Nargis was centered near a point located at 15.3 degrees north latitude and 88.2 degrees north longitude and moving northeast at 065 degrees at 8.1 miles per hour. The center was approximately 7 degrees southwest of Burma with sustained winds of 74.9 miles per hour, gusting to 92.2 miles per hour, forecast to strengthen. Maximum significant wave height was 27 feet.

[Odontology in Spain: towards the integration to the European high education space].

PubMed

Machuca Portillo, María del Carmen; Suárez Marchena, Cira; López del Valle, Lydia; Machuca Portillo, Guillermo; Bullón Fernández, Pedro

2005-03-01

The European Higher Education Space (EHES) is a project to harmonize all the European University systems in order that all of them will posses a homogeneous structure of undergraduate, graduate and post graduate studies. The time period established to implement this project is year 2010. The present paper describes the establishment of a new career degree model in Spain, the degree in Dentistry that started twenty years ago. Also it has been stated the number of the present Departments and Schools, the access system to Public University Schools of Spain, the evaluation system, and which are the new mechanisms incorporated in the Spanish University system to implement this integration to the EHEE. This is the moment to design the new master guidelines to obtain homogeneous career degrees that may imply more accessibility and mobility of students and professionals.

Quantum polarization fluctuations of an Airy beam in turbulent atmosphere in a slant path.

PubMed

Yin, Xia; Zhang, Licheng

2016-07-01

Polarization of light has many applications in quantum information processing, including quantum teleportation and dense coding. In this paper, we investigate the polarization fluctuations of Airy beams propagating in a slant turbulent channel under the "few-photon" limit. Using the quantum Stokes parameters and the quantum degree of polarization, we demonstrate that the degree of polarization of Airy beams increases significantly with the large number of the detection photons, and a higher photon-number level can retain the stability of polarization. Numerical simulations show that the longer propagation distance and the stronger turbulence will lead to less oscillatory behaviors and a decrease in the polarization degree of Airy beams, but a bigger exponential truncation factor will cause an increase in the polarization degree of Airy beams. In contrast with Gaussian beams, the degree of polarization of Airy beams is less affected by atmospheric turbulence and propagation distance under the same conditions, which means that Airy beams possess a resilient ability against turbulence-induced perturbations. These results indicate that Airy beams have great potential for applications in long-distance free-space optical communications to improve the performance of a polarization-encoded free-space quantum communication system.

Organization, Management and Function of International Space Station (ISS) Multilateral Medical Operations

NASA Technical Reports Server (NTRS)

Duncan, James M.; Bogomolov, V. V.; Castrucci, F.; Koike, Y.; Comtois, J. M.; Sargsyan, A. E.

2007-01-01

Long duration crews have inhabited the ISS since November of 2000. The favorable medical outcomes of its missions can be largely attributed to sustained collective efforts of all ISS Partners medical organizations. In-flight medical monitoring and support, although crucial, is just a component of the ISS system of Joint Medical Operations. The goal of this work is to review the principles, design, and function of the multilateral medical support of the ISS Program. The governing documents, which describe the relationships among all ISS partner medical organizations, were evaluated, followed by analysis of the roles, responsibilities, and decision-making processes of the ISS medical boards, panels, and working groups. The degree of integration of the medical support system was evaluated by reviewing the multiple levels of the status reviews and mission assurance activities carried out throughout the last six years. The Integrated Medical Group, consisting of physicians and other essential personnel in the mission control centers represents the front-line medical support of the ISS. Data from their day-to-day activities are presented weekly at the Space Medicine Operations Team (SMOT), where known or potential concerns are addressed by an international group of physicians. A broader status review is conducted monthly to project the state of crew health and medical support for the following month, and to determine measures to return to nominal state. Finally, a comprehensive readiness review is conducted during preparations for each ISS mission. The Multilateral Medical Policy Board (MMPB) issues medical policy decisions and oversees all health and medical matters. The Multilateral Space Medicine Board (MSMB) certifies crewmembers and visitors for training and space flight to the Station, and physicians to practice space medicine for the ISS. The Multilateral Medical Operations Panel (MMOP) develops medical requirements, defines and supervises implementation of operational countermeasures, environmental monitoring, medical care, and emergency medical services. MMOP assures the medical readiness of the Station for each subsequent mission or critical event. All boards and panels have functioned effectively and without interruptions even in various challenging circumstances. Based on the experience of the authors, consensus has prevailed as the primary nature of decisions made by all ISS medical groups, at all levels. The six first years of piloted operation have demonstrated the ability of the ISS medical authority groups and the medical infrastructure to implement medical policies and requirements, effectively interface with non-medical groups, and maintain the health and productivity of the crew in an integrated, multilaterally coordinated fashion. The medical support system appears to be mature and ready for further expansion of all Partners roles, and for the anticipated increase in the size of ISS crews.

Relationship of blood corticosterone, immunoglobulin and haematological values in young crocodiles (Crocodylus porosus) to water temperature, clutch of origin and body weight.

PubMed

Turton, J A; Ladds, P W; Manolis, S C; Webb, G J

1997-02-01

To examine whether sub-optimal temperature induced stress and immunosuppression in farmed saltwater crocodile (Crocodylus porosus) hatchlings. A clinico-pathological study. A total of 140 hatchlings were used. Body weight and length, plasma corticosterone and immunoglobulin concentrations and total and differential white blood cell counts were measured in 140 hatchlings from five clutches divided between five water temperature treatment groups. Initially all groups were housed at 32 degrees C for 10 weeks, then two groups (L, LC) were changed to low temperature (28 degrees C) and two groups (H, HC) to high temperature (36 degrees C), while one group (C) remained at 32 degrees C. The LC and HC groups were maintained at these temperatures for 10 days, after which the water temperature of both groups was returned to 32 degrees C. Blood samples were collected twice (at 6 and 9 weeks of age) before the initial temperature change, and at 10 days and 4 weeks after the initial temperature change (at 11.5 and 14 weeks of age). Except for an increase in plasma corticosterone in the HC group and a decrease in the L group when the temperature change was first introduced, changes in plasma corticosterone were not significant. There were no significant changes in immunoglobulin concentrations. There were, however, significant decreases in the total white cell and lymphocyte counts in the LC group after the temperature was decreased to 28 degrees C, and an increase in these counts after water temperature was returned to 32 degrees C. Clutch of origin had significant effects on body weight and length gains, and there were negative relationships between body weight and corticosterone concentrations and between body weight and immunoglobulin concentrations. As haematological changes indicative of stress were not associated with significant changes in serum corticosterone, immunosuppression in young crocodiles may be independent of the hypothalamic-pituitary-adrenal cortical axis.

Special Report: Top 100 Degree Producers. Part II.

ERIC Educational Resources Information Center

Black Issues in Higher Education, 1999

1999-01-01

Data on the colleges and universities producing the highest numbers of minority master's, doctoral, and first professional degrees in 1996-1997 are presented. Rankings are organized by degree level, ethnic group (African American, Hispanic American, Asian American, Native American), discipline group, and overall graduation rate. Breakouts are also…

MRI-visible perivascular spaces in cerebral amyloid angiopathy and hypertensive arteriopathy

PubMed Central

Boulouis, Gregoire; Pasi, Marco; Auriel, Eitan; van Etten, Ellis S.; Haley, Kellen; Ayres, Alison; Schwab, Kristin M.; Martinez-Ramirez, Sergi; Goldstein, Joshua N.; Rosand, Jonathan; Viswanathan, Anand; Greenberg, Steven M.; Gurol, M. Edip

2017-01-01

Objective: To assess MRI-visible enlarged perivascular spaces (EPVS) burden and different topographical patterns (in the centrum semiovale [CSO] and basal ganglia [BG]) in 2 common microangiopathies: cerebral amyloid angiopathy (CAA) and hypertensive arteriopathy (HA). Methods: Consecutive patients with spontaneous intracerebral hemorrhage (ICH) from a prospective MRI cohort were included. Small vessel disease MRI markers, including cerebral microbleeds (CMBs), cortical superficial siderosis (cSS), and white matter hyperintensities (WMH), were rated. CSO-EPVS/BG-EPVS were assessed on a validated 4-point visual rating scale (0 = no EPVS, 1 = <10, 2 = 11–20, 3 = 21–40, and 4 = >40 EPVS). We tested associations of predefined high-degree (score >2) CSO-EPVS and BG-EPVS with other MRI markers in multivariable logistic regression. We subsequently evaluated associations with CSO-EPVS predominance (i.e., CSO-EPVS > BG-EPVS) and BG-EPVS predominance pattern (i.e., BG-EPVS > CSO-EPVS) in adjusted multinomial logistic regression (reference group, BG-EPVS = CSO-EPVS). Results: We included 315 patients with CAA-ICH and 137 with HA-ICH. High-degree CSO-EPVS prevalence was greater in CAA-related ICH vs HA-related ICH (43.8% vs 17.5%, p < 0.001). In multivariable logistic regression, high-degree CSO-EPVS was associated with lobar CMB (odds ratio [OR] 1.33, 95% confidence interval [CI] 1.10–1.61, p = 0.003) and cSS (OR 2.08, 95% CI 1.30–3.32, p = 0.002). Deep CMBs (OR 2.85, 95% CI 1.75–4.64, p < 0.0001) and higher WMH volume (OR 1.02, 95% CI 1.01–1.04, p = 0.010) were predictors of high-degree BG-EPVS. A CSO-EPVS–predominant pattern was more common in CAA-ICH than in HA-ICH (75.9% vs 39.4%, respectively, p < 0.0001). CSO-PVS predominance was associated with lobar CMB burden and cSS, while BG-EPVS predominance was associated with HA-ICH and WMH volumes. Conclusions: Different patterns of MRI-visible EPVS provide insights into the dominant underlying microangiopathy type in patients with spontaneous ICH. PMID:28228568

Type and Use of Innovative Learning Environments in Australasian Schools. ILETC Survey 1

ERIC Educational Resources Information Center

Imms, Wesley; Mahat, Marian; Byers, Terry; Murphy, Dan

2017-01-01

This report provides results of a survey disseminated to over 6000 school principals in Australia and New Zealand (NZ). Participants were invited to provide their perceptions of (1) the types of learning spaces in their schools; (2) the types of teaching approaches observed in those spaces; (3) the degree to which teachers in those spaces utilised…

24 CFR 3280.804 - Disconnecting means and branch-circuit protective equipment.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ampere rating shall be marked on the blank space. (k) When a home is provided with installed service... permitted just inside a closet entry if the location is such that a clear space of 6 inches to easily... door can be extended to its full open position (at least 90 degrees). A clear working space at least 30...

British Degrees Made in Hong Kong: An Enquiry into the Role of Space and Place in Transnational Education

ERIC Educational Resources Information Center

Leung, Maggi W. H.; Waters, Johanna L.

2013-01-01

The fundamental logic of transnational education programmes is a one-to-one transfer of institutional capital across space and an unimportance of place. This article interrogates these presumptions and argues that space and place play an important role in transnational education. Drawing on research that examines the experiences of students and…

[Microclimate and comfortable degree of Shanghai urban open spaces in summer].

PubMed

Cao, Dan; Zhou, Li-chen; Mao, Yi-wei; Li, Yin; Liu, Yi-ning; Wang, Tian-hou

2008-08-01

Based on the observation data of air temperature, relative humidity, wind speed, and solar radiation from May to August 2006, the regulation effects of five types of open spaces (square, fountain, grassplot, corridor, and woodland) in Shanghai urban districts on the microclimate were analyzed, and discomfort index (DI) was introduced to evaluate the effects of these five types of open spaces on human body' s comfortable degree. The results showed that there existed definite differences in the air temperature and relative humidity among the open spaces, with the mean temperature decreased in the order of square > grassplot > fountain > corridor > woodland, and the mean relative humidity decreased in the order of woodland > corridor > fountain > grassplot > square. The area of the square, the wind speed and direction near the fountain, the grass species on the grass-plot, the width and tree coverage of the corridor, and the tree coverage and canopy height of the woodland had significant correlations with the microclimate parameters of corresponding open spaces. Comparing with other three types of open spaces, woodland and corridor had better regulation effects on the microclimate via shading, decreasing air temperature, and increasing relative humidity.

[The relation of workspace and installation space of epicyclic kinematics with six degrees of freedom].

PubMed

Pott, Peter P; Schwarz, Markus L R

2007-10-01

The kinematics of a robotic device significantly determines its installation space when it comes to technical realisation. With regard to the deployment of robotic manipulators in surgery, manipulators with a preferably small installation space are needed. This study describes six versions of novel epicyclic kinematics with six degrees of freedom (DOF). At first, the kinematics functionality was analysed using Gruebler's formula. Subsequently, the quantitative determination of the relation of workspace and installation space was performed using Matlab algorithms. To qualitatively describe the shape of the workspace, the Matlab visualisation features were utilised. For comparison, the well-known Hexapod was used. The assessed kinematics had 6-DOF-functionality. It became apparent that one version of the epicyclic kinematics having two 3-DOF disk systems mounted in a parallel way featured a particularly good relation of workspace and installation space. Compared to the Hexapod, this is approximately four times better. The shape of the workspaces of all epicyclic kinematics assessed was convex and compact. It could be shown that a novel epicyclic kinematics has a notably advantageous relation of workspace and installation space. Apparently, it seems to be well suited for the deployment in robotic machines for surgical procedures.

Electron microscope studies of nano-domain structures in Ru-based magneto-superconductors: RuSr(2)Gd(1.5)Ce(0.5)Cu(2)O(10-delta) (Ru-1222) and RuSr(2)GdCu(2)O(8) (Ru-1212).

PubMed

Yokosawa, Tadahiro; Awana, V P S Veer Pal Singh; Kimoto, Koji; Takayama-Muromachi, Eiji; Karppinen, Maarit; Yamauchi, Hisao; Matsui, Yoshio

2004-01-01

Microstructures of the RuSr(2)Gd(1.5)Ce(0.5)Cu(2)O(10-delta) (Ru-1222) and RuSr(2)GdCu(2)O(8) (Ru-1212) magneto-superconductors have been investigated by using selected-area electron diffraction, convergent-beam electron diffraction, dark-field electron microscopy and high-resolution electron microscopy at room temperature. Both Ru-1212 and Ru-1222 consist of nm-size domains stacked along the [Formula: see text] direction, where the domains are formed by two types of superstructures due to ordering of rotated RuO(6) octahedra about the c-axis. In Ru-1212, both primitive-and body-centered tetragonal superstructures (the possible space groups: P4/mbm and I4/mcm) are derived to form the corresponding nm-domains. It is of great interest that Ru-1212 consists of domains of two crystallographically different superstructures, while the similar domains observed in Ru-1222 have crystallographically identical superstructure with an orthorhombic symmetry (possible space group: Aeam), related by 90 degrees rotation around the c-axis (Yokosawa et al., 2003, submitted for publication).

Earth Observations taken by the Expedition 10 crew

NASA Image and Video Library

2005-01-23

ISS010-E-14618 (23 January 2005) --- Egypt's Lake Nasser, centered roughly at 22.64 degrees north latitude and 32.45 degrees east longitude, was captured with an electronic still camera by the Expedition 10 crew onboard the International Space Station. Sunglint on the lake makes it more easily visible.

KSC-03PD-2862

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. In the Orbiter Processing Facility, the nose cap of the orbiter Atlantis rests on a stand after its removal from the orbiter for routine inspection. The nose cap is made of reinforced carbon-carbon (RCC), which has an operating range of minus 250 degrees F to about 3,000 degrees F.

Asteroids: Does Space Weathering Matter?

NASA Technical Reports Server (NTRS)

Gaffey, Michael J.

2001-01-01

The interpretive calibrations and methodologies used to extract mineralogy from asteroidal spectra appear to remain valid until the space weathering process is advanced to a degree which appears to be rare or absent on asteroid surfaces. Additional information is contained in the original extended abstract.

Eccentric knee flexor torque following anterior cruciate ligament surgery.

PubMed

Osternig, L R; James, C R; Bercades, D T

1996-10-01

The purposes of this study were to compare eccentric knee flexor torque and muscle activation in the limbs of normal (NOR) subjects and in subjects who had undergone unilateral ACI, autograft surgical reconstruction (INJ) and to assess the effect of movement speed on EMG/ torque ratios and eccentric-concentric actions. Fourteen subjects (7 NOR and 7 INJ) were tested for knee eccentric flexor torque and EMG activity at four isokinetic speeds (15 degrees, 30 degrees, 45 degrees and 60 degrees.s-1). Results revealed that post-surgical limbs (ACL) produced significantly less (P < 0.05) eccentric torque and flexor EMG activity at 60 degrees.s-1 than uninjured (UNI) contralateral limbs. Eccentric torque rose significantly as speed increased from 45 degrees to 60 degrees.s-1 for surgical group uninjured limbs and NOR group left and right limbs. Eccentric flexor torque increased with speed for both groups and approximated equality with concentric extensor torque at 60 degrees.s-1 for INJ group ACL and UNI limbs. Concentric flexor muscle EMG/torque ratios were 30-191% greater than eccentric muscle actions across groups and speeds. The results suggest that ACL dysfunction may result in reduced eccentric flexor torque at rapid movement speeds, that eccentric flexor torque increases with movement speed and may have the capacity to counter forceful extensor concentric torque, and that eccentric muscle actions produce less muscle activation per unit force than concentric actions which may reflect reduced energy cost.

Parametric Coding of the Size and Clutter of Natural Scenes in the Human Brain

PubMed Central

Park, Soojin; Konkle, Talia; Oliva, Aude

2015-01-01

Estimating the size of a space and its degree of clutter are effortless and ubiquitous tasks of moving agents in a natural environment. Here, we examine how regions along the occipital–temporal lobe respond to pictures of indoor real-world scenes that parametrically vary in their physical “size” (the spatial extent of a space bounded by walls) and functional “clutter” (the organization and quantity of objects that fill up the space). Using a linear regression model on multivoxel pattern activity across regions of interest, we find evidence that both properties of size and clutter are represented in the patterns of parahippocampal cortex, while the retrosplenial cortex activity patterns are predominantly sensitive to the size of a space, rather than the degree of clutter. Parametric whole-brain analyses confirmed these results. Importantly, this size and clutter information was represented in a way that generalized across different semantic categories. These data provide support for a property-based representation of spaces, distributed across multiple scene-selective regions of the cerebral cortex. PMID:24436318

A continuum model for dynamic analysis of the Space Station

NASA Technical Reports Server (NTRS)

Thomas, Segun

1989-01-01

Dynamic analysis of the International Space Station using MSC/NASTRAN had 1312 rod elements, 62 beam elements, 489 nodes and 1473 dynamic degrees of freedom. A realtime, man-in-the-loop simulation of such a model is impractical. This paper discusses the mathematical model for realtime dynamic simulation of the Space Station. Several key questions in structures and structural dynamics are addressed. First, to achieve a significant reduction in the number of dynamic degrees of freedom, a continuum equivalent representation of the Space Station truss structure which accounted for the unsymmetry of the basic configuration and resulted in the coupling of extensional and transverse deformation, is developed. Next, dynamic equations for the continuum equivalent of the Space Station truss structure are formulated using a matrix version of Kane's dynamical equations. Flexibility is accounted for by using a theory that accommodates extension, bending in two principal planes and shear displacement. Finally, constraint equations suitable for dynamic analysis of flexible bodies with closed loop configuration are developed and solution of the resulting system of equations is based on the zero eigenvalue theorem.

Site Fidelity in Space Use by Spider Monkeys (Ateles geoffroyi) in the Yucatan Peninsula, Mexico

PubMed Central

Ramos-Fernandez, Gabriel; Smith Aguilar, Sandra E.; Schaffner, Colleen M.; Vick, Laura G.; Aureli, Filippo

2013-01-01

Animal home ranges may vary little in their size and location in the short term but nevertheless show more variability in the long term. We evaluated the degree of site fidelity of two groups of spider monkeys (Ateles geoffroyi) over a 10- and 13-year period, respectively, in the northeastern Yucatan peninsula, Mexico. We used the Local Convex Hull method to estimate yearly home ranges and core areas (defined as the 60% probability contour) for the two groups. Home ranges varied from 7.7 to 49.6 ha and core areas varied from 3.1 to 9.2 ha. We evaluated the degree of site fidelity by quantifying the number of years in which different areas were used as either home ranges or core areas. Large tracts were used only as home ranges and only for a few years, whereas small areas were used as either core area or home range for the duration of the study. The sum of the yearly core areas coincided partially with the yearly home ranges, indicating that home ranges contain areas used intermittently. Home ranges, and especially core areas, contained a higher proportion of mature forest than the larger study site as a whole. Across years and only in one group, the size of core areas was positively correlated with the proportion of adult males in the group, while the size of home ranges was positively correlated with both the proportion of males and the number of tree species included in the diet. Our findings suggest that spider monkey home ranges are the result of a combination of long-term site fidelity and year-to-year use variation to enable exploration of new resources. PMID:23675427

Effective degrees of freedom: a flawed metaphor

PubMed Central

Janson, Lucas; Fithian, William; Hastie, Trevor J.

2015-01-01

Summary To most applied statisticians, a fitting procedure’s degrees of freedom is synonymous with its model complexity, or its capacity for overfitting to data. In particular, it is often used to parameterize the bias-variance tradeoff in model selection. We argue that, on the contrary, model complexity and degrees of freedom may correspond very poorly. We exhibit and theoretically explore various fitting procedures for which degrees of freedom is not monotonic in the model complexity parameter, and can exceed the total dimension of the ambient space even in very simple settings. We show that the degrees of freedom for any non-convex projection method can be unbounded. PMID:26977114

Analysis of peg formation in cucumber seedlings grown on clinostats and in a microgravity (space) environment.

PubMed

Link, B M; Cosgrove, D J

1999-12-01

In young cucumber seedlings, the peg is a polar out-growth of tissue that functions by snagging the seed coat, thereby freeing the cotyledons. Previous studies have indicated that peg formation is gravity dependent. In this study we analyzed peg formation in cucumber seedlings (Cucumis sativus L. cv Burpee Hybrid II) grown under conditions of normal gravity, microgravity, and simulated microgravity (clinostat rotation). Seeds were germinated on the ground, in clinostats and on board the space shuttle (STS 95) for 1-2 days, frozen and subsequently examined for their stage of development, degree of hook formation, number of pegs formed, and peg morphology. The frequency of peg formation in space grown seedlings was found to be nearly identical to that of clinostat grown seedlings and to differ from that of seedlings germinated under normal gravity only in a minority of cases; approximately 6% of the seedlings formed two pegs and nearly 2% of the seedlings lacked pegs, whereas such abnormalities did not occur in ground controls. The degree of hook formation was found to be less pronounced for space grown seedlings, compared to clinostat grown seedlings, indicating a greater degree of decoupling between peg formation and hook formation in space. Nonetheless, in all seedlings having single pegs and a hook, the peg was found to be positioned correctly on the inside of the hook, showing that there is coordinate development even in microgravity environments. Peg morphologies were altered in space grown samples, with the pegs having a blunt appearance and many pegs showing alterations in expansion, with the peg extending out over the edges of the seed coat and downwards. These phenotypes were not observed in clinostat or ground grown seedlings.

Analysis of peg formation in cucumber seedlings grown on clinostats and in a microgravity (space) environment

NASA Technical Reports Server (NTRS)

Link, B. M.; Cosgrove, D. J.

1999-01-01

In young cucumber seedlings, the peg is a polar out-growth of tissue that functions by snagging the seed coat, thereby freeing the cotyledons. Previous studies have indicated that peg formation is gravity dependent. In this study we analyzed peg formation in cucumber seedlings (Cucumis sativus L. cv Burpee Hybrid II) grown under conditions of normal gravity, microgravity, and simulated microgravity (clinostat rotation). Seeds were germinated on the ground, in clinostats and on board the space shuttle (STS 95) for 1-2 days, frozen and subsequently examined for their stage of development, degree of hook formation, number of pegs formed, and peg morphology. The frequency of peg formation in space grown seedlings was found to be nearly identical to that of clinostat grown seedlings and to differ from that of seedlings germinated under normal gravity only in a minority of cases; approximately 6% of the seedlings formed two pegs and nearly 2% of the seedlings lacked pegs, whereas such abnormalities did not occur in ground controls. The degree of hook formation was found to be less pronounced for space grown seedlings, compared to clinostat grown seedlings, indicating a greater degree of decoupling between peg formation and hook formation in space. Nonetheless, in all seedlings having single pegs and a hook, the peg was found to be positioned correctly on the inside of the hook, showing that there is coordinate development even in microgravity environments. Peg morphologies were altered in space grown samples, with the pegs having a blunt appearance and many pegs showing alterations in expansion, with the peg extending out over the edges of the seed coat and downwards. These phenotypes were not observed in clinostat or ground grown seedlings.

Spatiotemporal variation characteristics of green space ecosystem service value at urban fringes: A case study on Ganjingzi District in Dalian, China.

PubMed

Yang, Jun; Guan, Yingying; Xia, Jianhong Cecilia; Jin, Cui; Li, Xueming

2018-10-15

In this study, a green space classification system for urban fringes was established based on multisource land use data from Ganjingzi District, China (2000-2015). The purpose of this study was to explore the spatiotemporal variation of green space landscapes and ecosystem service values (ESV). During 2006-2015, as urbanization advanced rapidly, the green space area decreased significantly (359.57 to 213.46 km 2 ), the ESV decreased from 397.42 to 124.93 million yuan, and the dynamic degrees of ESV variation were always <0. The green space large plaque index and class area both declined and the number of plaques and plaque density increased, indicating green space landscape fragmentation. The dynamic degrees of ESV variation in western and northern regions (with relatively intensive green space distributions) were higher than in the east. The ESV for closed forestland and sparse woodland had the highest functional values of ecological regulation and support, whereas dry land and irrigated cropland provided the highest functional values of production supply. The findings of this study are expected to provide support for better construction practices in Dalian and for the improvement of the ecological environment. Copyright © 2018 Elsevier B.V. All rights reserved.

Embrittlement of MISSE 5 Polymers After 13 Months of Space Exposure

NASA Technical Reports Server (NTRS)

Guo, Aobo; Yi, Grace T.; Ashmead, Claire C.; Mitchell, Gianna G.; deGroh, Kim K.

2012-01-01

Understanding space environment induced degradation of spacecraft materials is essential when designing durable and stable spacecraft components. As a result of space radiation, debris impacts, atomic oxygen interaction, and thermal cycling, the outer surfaces of space materials degrade when exposed to low Earth orbit (LEO). The objective of this study was to measure the embrittlement of 37 thin film polymers after LEO space exposure. The polymers were flown aboard the International Space Station and exposed to the LEO space environment as part of the Materials International Space Station Experiment 5 (MISSE 5). The samples were flown in a nadir-facing position for 13 months and were exposed to thermal cycling along with low doses of atomic oxygen, direct solar radiation and omnidirectional charged particle radiation. The samples were analyzed for space-induced embrittlement using a bend-test procedure in which the strain necessary to induce surface cracking was determined. Bend-testing was conducted using successively smaller mandrels to apply a surface strain to samples placed on a semi-suspended pliable platform. A pristine sample was also tested for each flight sample. Eighteen of the 37 flight samples experienced some degree of surface cracking during bend-testing, while none of the pristine samples experienced any degree of cracking. The results indicate that 49 percent of the MISSE 5 thin film polymers became embrittled in the space environment even though they were exposed to low doses (approx.2.75 krad (Si) dose through 127 mm Kapton) of ionizing radiation.

Pilot Joseph Algranti entering a McDonnell F2H-2B Banshee

NASA Image and Video Library

1958-02-21

Pilot Joe Algranti climbs into the cockpit of a McDonnell F2H-2B Banshee on the tarmac at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. Nine months later the laboratory became part of the new National Aeronautics and Space Administration, and the NACA logo was permanently removed from the hangar. Algranti served as a Navy fighter pilot from 1946 to 1947 and earned a Physics degree from the University of North Carolina. He joined the NACA Lewis staff in 1951 witnessed the technological transformation from high speed flight to space. At Lewis Algranti piloted icing research flights, operated the liquid-hydrogen pump system for Project Bee, and served as the primary test subject for the Multi-Axis Space Test Inertia Facility (MASTIF). The MASTIF was a device used to train the Mercury astronauts how to control a spinning capsule. In 1960, Algranti and fellow Lewis pilots Warren North and Harold Ream transferred to NASA’s Space Task Group at Langley to actively participate in the space program. Two years later, Algranti became the Chief of Aircraft Operations and Chief Test Pilot at NASA’s new Manned Space Center in Houston. Algranti earned notoriety in 1968 when he test flew the first Lunar Landing Training Vehicle. He operated the vehicle four minutes before being forced to eject moments before it impacted the ground. Algranti also flew the NASA’s modified Boeing 747 Shuttle Carrier Aircraft, the Super Guppy, and the KC-135 "Vomit Comet" training aircraft. He retired in 1992 with over 40 years of NASA service.

Color space distortions in patients with type 2 diabetes mellitus.

PubMed

Feitosa-Santana, Claudia; Oiwa, Nestor N; Paramei, Galina V; Bimler, David; Costa, Marcelo F; Lago, Marcos; Nishi, Mauro; Ventura, Dora F

2006-01-01

Color vision impairment was examined in patients with type 2 diabetes mellitus (DM2) without retinopathy. We assessed the type and degree of distortions of individual color spaces. DM2 patients (n = 32), and age-matched controls (n = 20) were tested using the Farnsworth D-15 and the Lanthony D-15d tests. In addition, subsets of caps from both tests were employed in a triadic procedure (Bimler & Kirkland, 2004). Matrices of inter-cap subjective dissimilarities were estimated from each subject's "odd-one-out" choices, and processed using non-metric multidimensional scaling. Two-dimensional color spaces, individual and group (DM2 patients; controls), were reconstructed, with the axes interpreted as the R/G and B/Y perceptual opponent systems. Compared to controls, patient results were not significant for the D-15 and D-15d. In contrast, in the triadic procedure the residual distances were significantly different compared to controls: right eye, P = 0.021, and left eye, P = 0.022. Color space configurations for the DM2 patients were compressed along the B/Y and R/G dimensions. The present findings agree with earlier studies demonstrating diffuse losses in early stages of DM2. The proposed method of testing uses color spaces to represent discrimination and provides more differentiated quantitative diagnosis, which may be interpreted as the perceptual color system affected. In addition, it enables the detection of very mild color vision impairment that is not captured by the D-15d test. Along with fundoscopy, individual color spaces may serve for monitoring early functional changes and thereby to support a treatment strategy.

Benefit of a 360-degree horizontal turn following premedication with simethicone on image quality during gastroendoscopy: a randomized controlled trial

PubMed Central

Wang, Chunhua; Liu, Haiyan; Wang, Xiuming; Shen, Xiaochun; Yang, Yingying; Sun, Wenjing; Yan, Qingjun; Cao, Yan; Wang, Xueqin; Lan, Chunhui; Chen, Dongfeng

2015-01-01

Objectives: To investigate whether a 360-degree horizontal turn after oral premedication with simethicone improves the mucosal visibility during gastroendoscopic examination, and to determine the proper time to turn over the patient. Methods: This study involved 993 patients scheduled for gastroendoscopy. Just before gastroendoscopy, after oral premedication with simethicone, patients were randomly assigned to three groups: in Group A, patients waited for 20 min before gastroendoscopy; in Group B, patients were separately waited for 5/10/15/20 min and were then turned 360 degrees just before gastroendoscopy; in Group C, patients were immediately turned 360 degrees and then separately waited for 5/10/15/20 min before examination. The sum of the gastric mucosal visibility scores (MVS) was calculated after the examination. The MVS and proportion of images with higher visibility scores for the mucosal surface. Lower scores indicate better visibility of the mucosal surface. Results: In Groups B and Groups C, when waiting time more than 10 min had lower mean total MVS than Group A. The MVS of four subgroups of Group B were not different from those of Group C. Conclusion: Oral premedication with simethicone and immediately make a body posture change (turning over 360 degrees) then waiting for 10min can increase the image quality during gastroendoscopy and effectively decrease the premedication time. PMID:26064342

Benefit of a 360-degree horizontal turn following premedication with simethicone on image quality during gastroendoscopy: a randomized controlled trial.

PubMed

Wang, Chunhua; Liu, Haiyan; Wang, Xiuming; Shen, Xiaochun; Yang, Yingying; Sun, Wenjing; Yan, Qingjun; Cao, Yan; Wang, Xueqin; Lan, Chunhui; Chen, Dongfeng

2015-01-01

To investigate whether a 360-degree horizontal turn after oral premedication with simethicone improves the mucosal visibility during gastroendoscopic examination, and to determine the proper time to turn over the patient. This study involved 993 patients scheduled for gastroendoscopy. Just before gastroendoscopy, after oral premedication with simethicone, patients were randomly assigned to three groups: in Group A, patients waited for 20 min before gastroendoscopy; in Group B, patients were separately waited for 5/10/15/20 min and were then turned 360 degrees just before gastroendoscopy; in Group C, patients were immediately turned 360 degrees and then separately waited for 5/10/15/20 min before examination. The sum of the gastric mucosal visibility scores (MVS) was calculated after the examination. The MVS and proportion of images with higher visibility scores for the mucosal surface. Lower scores indicate better visibility of the mucosal surface. In Groups B and Groups C, when waiting time more than 10 min had lower mean total MVS than Group A. The MVS of four subgroups of Group B were not different from those of Group C. Oral premedication with simethicone and immediately make a body posture change (turning over 360 degrees) then waiting for 10min can increase the image quality during gastroendoscopy and effectively decrease the premedication time.

Cold cardioplegia versus hypothermia for myocardial protection. Randomized clinical study.

PubMed

Conti, V R; Bertranou, E G; Blackstone, E H; Kirklin, J W; Digerness, S B

1978-11-01

Seventeen of 34 consecutive patients undergoing coronary artery bypass grafting were randomly assigned to one of two methods of myocardial preservation. With the cold cardioplegic method (Group A), a 4 degrees C. asanguineous solution with 30 mEq. of potassium per liter was infused into the aortic root for about 2 minutes immediately after aortic cross-clamping and again after about 45 minutes or when myocardial temperature rose above 19 degrees C. External cardiac cooling was provided by constant infusion of 4 degrees C. Ringer's solution into the pericardium. Seventeen patients were assigned to simple cardiac cooling by hypothermic systemic perfusion before aortic cross-clamping plus external cardiac cooling (Group B). Electromechanical activity ceased within 1 to 2 minutes in Group A but continued throughout the ischemic period in 14 patients in Group B. Myocardial temperature (mean for all observations) during aortic cross-clamping was 17.2 +/- 0.44 degrees C. In Group A and 24.0 +/- 0.70 degrees C. in Group B. Operating conditions were better in Group A. Card-ac function early postoperatively was good in both groups clinically and according to measurements, but only in the cold cardioplegic group (A) was cardiac index not adversely affected by longer cross-clamp time. Myocardial necrosis occurred in both groups but was probably less in the cold cardioplegic group. Thirteen patients (76 percent) in Group A had no electrocardiographic evidence of myocardial injury, compared with eight (47 percent) in Group B (p = 0.08). Eleven (65 percent of Group A had no or short-lived appearance of ceatine phosphokinase isoenzyme (CK-MB), compared with six (35 percent) of Group B (p = 0.08). Time-related CK-MB and SGOT mean levels were consistently lower in Group A.

Can a print-based intervention increase screening for first degree relatives of people with colorectal cancer? A randomised controlled trial.

PubMed

Carey, Mariko; Sanson-Fisher, Robert; Macrae, Finlay; Cameron, Emilie; Hill, David; D'Este, Catherine; Simmons, Jody; Doran, Christopher

2016-12-01

To test the effectiveness of a targeted print-based intervention to improve screening adherence in first degree relatives of people with colorectal cancer (CRC). People with CRC and their adult first degree relatives were identified through a population-based cancer registry and randomly allocated as a family unit to the intervention or control condition. The control group received general information about CRC screening. The intervention group received printed advice regarding screening that was targeted to their risk level. Screening adherence was assessed at baseline and at 12 months via self report. 752 (25%) index cases and 574 (34%) eligible first degree relatives consented to take part in the trial and completed baseline interviews. At 12 months, 58% of first degree relatives in the control group and 61% in the intervention group were adherent to screening guidelines (mixed effects logistic regression group by time interaction effect =2.7; 95%CI=1.2-5.9; P=0.013). Subgroup analysis indicated that the intervention was only effective for those with the lowest risk. Provision of personalised risk information may have a modest effect on adherence to CRC screening recommendations among first degree relatives of people diagnosed with CRC. Improved strategies for identifying and engaging first degree relatives are needed to maximise the population impact of the intervention. © 2016 The Authors.

[Short-term effect of black film covering on Oncomelania hupensis snail control in marshland and lake regions].

PubMed

Zheng, Sheng-bang; Zhou, Yi-biao; Li, Lin-han; Wu, Jin-yi; Yao, Bao-dong; Zhu, Shao-ping; Wei, Cheng-jian; Li, Fu-ping; Hu, Ben-jiao; Ren, Guang-hui; Yi, Ping; Jiang, Qing-wu

2013-08-01

To evaluate the short-term effect of the black film covering combined with niclosamide on Oncomelania hupensis snail control in marshland and lake regions. A ditch with snails in Anxiang County was selected as the experimental sites. The ditch was divided into 3 groups: a film group, a niclosamide group, and a niclosamide and film group. The snails were surveyed before the test and 1, 3, 5, 7 days after the experiment. After the film covering, the highest temperature of the surface of soil was 63.7 degrees C on the first day, and the temperature higher than 40 degrees C lasted 4.34 hours. On the second day, the highest temperature was 52.3 degrees C, and the temperature higher than 40 degrees C lasted 4.96 hours. On the fourth day and fifth day, the temperature was lower than 30 degrees C, while the temperature was lower than 34 degrees C on the sixth day. On the seventh day of the experiment, the snail death rates of the film group, the niclosamide group, and the niclosamide and film group on the soil surface were 16.36%, 58.40% and 53.57%, respectively. On the seventh day, the snail death rates of the film group, and the niclosamide and film group under the soil were 20.00% and 40.00%, respectively, while no snails were found under the soil in the niclosamide group 3 days after the experiment. In mesh bags, the snail death rates of the film group, the niclosamide group, and the niclosamide and film group were 84.00%, 95.33% and 95.33%, respectively. The short-term effect of the black film covering on snail control is not obvious, and the black film covering does no promote the molluscicidal effect of niclosamide.

Flexible intuitions of Euclidean geometry in an Amazonian indigene group

PubMed Central

Izard, Véronique; Pica, Pierre; Spelke, Elizabeth S.; Dehaene, Stanislas

2011-01-01

Kant argued that Euclidean geometry is synthesized on the basis of an a priori intuition of space. This proposal inspired much behavioral research probing whether spatial navigation in humans and animals conforms to the predictions of Euclidean geometry. However, Euclidean geometry also includes concepts that transcend the perceptible, such as objects that are infinitely small or infinitely large, or statements of necessity and impossibility. We tested the hypothesis that certain aspects of nonperceptible Euclidian geometry map onto intuitions of space that are present in all humans, even in the absence of formal mathematical education. Our tests probed intuitions of points, lines, and surfaces in participants from an indigene group in the Amazon, the Mundurucu, as well as adults and age-matched children controls from the United States and France and younger US children without education in geometry. The responses of Mundurucu adults and children converged with that of mathematically educated adults and children and revealed an intuitive understanding of essential properties of Euclidean geometry. For instance, on a surface described to them as perfectly planar, the Mundurucu's estimations of the internal angles of triangles added up to ∼180 degrees, and when asked explicitly, they stated that there exists one single parallel line to any given line through a given point. These intuitions were also partially in place in the group of younger US participants. We conclude that, during childhood, humans develop geometrical intuitions that spontaneously accord with the principles of Euclidean geometry, even in the absence of training in mathematics. PMID:21606377

[Evaluation of diffuse cerebral atrophy in patients with a history of traumatic brain injury and its relation to cognitive deterioration].

PubMed

Narberhaus, A; Segarra-Castells, M D; Verger-Maestre, K; Serra-Grabulosa, J M; Salgado-Pineda, P; Bartomeus-Jené, F; Mercader-Sobrequés, J M

Diffuse damage secondary to traumatic brain injury (TBI) can be studied through volumetric analysis of several structures that are sensible to this kind of injury, such as corpus callosum, ventricular system, hippocampus, basal ganglia and the volume of cerebrospinal fluid spaces. Our aim is to describe how closed head injury (CHI) occurred in early years produce diffuse damage, and how this damage affects general cognitive functioning at long term. Initially the group of subjects was composed of 27 head injured children and adolescents following paediatric moderate to severe TBI. From this initial group we selected 15 patients without focal lesion, or in case of having suffered focal lesion, this was smaller than 2,600 mm3. These subjects were assessed by means of volumetric analysis of cerebrospinal fluid spaces, corpus callosum, hippocampus and caudate nucleus, comparing the results with a matched control group. We calculated the degree of general cognitive ability of these subjects through tests of intellectual, memory, frontal lobe and motor speed functioning. This study demonstrates that early CHI produce a volume decrease in all measured structures. Corpus callosum atrophy is the factor that better explains general cognitive impairment. Diffuse damage secondary to moderate to severe peadiatric TBI has long term effects on several cerebral structures and on cognitive performance. Corpus callosum atrophy is the best predictor for general cognitive impairment, compared with other affected structures.

Co-assembly of Zn(SPh){sub 2} and organic linkers into helical and zig-zag polymer chains

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

Liu Yi; Yu Lingmin; Loo, Say Chye Joachim

2012-07-15

Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (EG=ethylene glycol) (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized under solvothermal conditions at 150 Degree-Sign C or room temperature by the co-assembly of Zn(SPh){sub 2} and organic linkers such as 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPyTA) and 1,3-bis(trans-4-pyridylvinyl)benzene (BPyVB). X-ray crystallography study reveals that both polymers 1 and 2 crystallize in space group P2{sub 1}/c of the monoclinic system. The solid-state UV-vis absorption spectra show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up tomore » 110 Degree-Sign C and 210 Degree-Sign C. - Graphical abstract: Two novel one-dimensional coordination polymers, single helicate [Zn(SPh){sub 2}(TPyTA)(EG)]{sub n} (1) and zig-zag structure [Zn(SPh){sub 2}(BPyVB)]{sub n} (2), were synthesized. Solid-state UV-vis absorptions show that 1 and 2 have maxium absorption onsets at 400 nm and 420 nm, respectively. TGA analysis indicates that 1 and 2 are stable up to 110 Degree-Sign C and 210 Degree-Sign C. Highlights: Black-Right-Pointing-Pointer Two novel one-dimensional coordination polymers have been synthesized. Black-Right-Pointing-Pointer TPyTA results in helical structures in 1 while BPyVB leads to zig-zag chains in 2. Black-Right-Pointing-Pointer Solid-state UV-vis absorption spectra and TGA analysis of the title polymers were studied.« less

Bulgarian contributions to the development of space biology and medicine

NASA Technical Reports Server (NTRS)

Serafimov, K.

1980-01-01

Several aspects of aerospace medicine are discussed. Particular attention is given to the following: the effects of anoxia; the effects of positive radial acceleration; and the effects of various degrees of athletic conditioning and drugs on the tolerance of space flight factors.

Uniaxial strain control of spin-polarization in multicomponent nematic order of BaFe 2As 2

DOE PAGES

Kissikov, T.; Sarkar, R.; Lawson, M.; ...

2018-03-13

The iron-based high temperature superconductors exhibit a rich phase diagram reflecting a complex interplay between spin, lattice, and orbital degrees of freedom. The nematic state observed in these compounds epitomizes this complexity, by entangling a real-space anisotropy in the spin fluctuation spectrum with ferro-orbital order and an orthorhombic lattice distortion. A subtle and less-explored facet of the interplay between these degrees of freedom arises from the sizable spin-orbit coupling present in these systems, which translates anisotropies in real space into anisotropies in spin space. We present nuclear magnetic resonance studies, which reveal that the magnetic fluctuation spectrum in the paramagneticmore » phase of BaFe 2As 2 acquires an anisotropic response in spin-space upon application of a tetragonal symmetry-breaking strain field. Lastly, our results unveil an internal spin structure of the nematic order parameter, indicating that electronic nematic materials may offer a route to magneto-mechanical control.« less

Effective degrees of freedom of a random walk on a fractal.

PubMed

Balankin, Alexander S

2015-12-01

We argue that a non-Markovian random walk on a fractal can be treated as a Markovian process in a fractional dimensional space with a suitable metric. This allows us to define the fractional dimensional space allied to the fractal as the ν-dimensional space F(ν) equipped with the metric induced by the fractal topology. The relation between the number of effective spatial degrees of freedom of walkers on the fractal (ν) and fractal dimensionalities is deduced. The intrinsic time of random walk in F(ν) is inferred. The Laplacian operator in F(ν) is constructed. This allows us to map physical problems on fractals into the corresponding problems in F(ν). In this way, essential features of physics on fractals are revealed. Particularly, subdiffusion on path-connected fractals is elucidated. The Coulomb potential of a point charge on a fractal embedded in the Euclidean space is derived. Intriguing attributes of some types of fractals are highlighted.

Weak Lensing from Space I: Instrumentation and Survey Strategy

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

Rhodes, Jason; Refregier, Alexandre; Massey, Richard

A wide field space-based imaging telescope is necessary to fully exploit the technique of observing dark matter via weak gravitational lensing. This first paper in a three part series outlines the survey strategies and relevant instrumental parameters for such a mission. As a concrete example of hardware design, we consider the proposed Supernova/Acceleration Probe (SNAP). Using SNAP engineering models, we quantify the major contributions to this telescope's Point Spread Function (PSF). These PSF contributions are relevant to any similar wide field space telescope. We further show that the PSF of SNAP or a similar telescope will be smaller than currentmore » ground-based PSFs, and more isotropic and stable over time than the PSF of the Hubble Space Telescope. We outline survey strategies for two different regimes - a ''wide'' 300 square degree survey and a ''deep'' 15 square degree survey that will accomplish various weak lensing goals including statistical studies and dark matter mapping.« less

Wallops Station and the Creation of an American Space Program. Master's Degree awarded by Univ. of Maryland-Baltimore County

NASA Technical Reports Server (NTRS)

Wallace, Harold D., Jr.

1997-01-01

As part of the NASA history series a detailed history of Wallops Space Flight Facility from 1957 to 1966 is given. Discussions of Sputnik, NASA, Piloted Space Flight, Space Science Research, and comments on the changes the facility went through during the period are presented. Several appendices are attached as well covering R&D Launches, the NACA Era, organizational charts, Wallops' complement, and selected international cooperative programs.

MELFI-3 Cold Box inspection

NASA Image and Video Library

2015-03-13

ISS043e000724 (03/13/2015) --- ESA (European Space Agency) astronaut Samantha Cristoforetti, Expedition 43 flight engineer works daily on science and maintenance duties on board the International Space Station. She is inspecting the Minus Eighty-degree Laboratory Freezer called by the shorter title "MELFI-3 Cold Box inspection". Astronauts are trained for long periods at the Johnson Space Center and in Russia before their missions in space begin so that they are fully trained for these complex duties.

The Top 100 Bachelor's Degrees Conferred

ERIC Educational Resources Information Center

Borden, Victor M. H.

2011-01-01

This article presents this year's Top 100 institutions that conferred the most bachelor's degrees to students of color in academic year 2009-2010. It shows the total number of bachelor's degrees for a specific minority group or for total minorities, with subtotals for women and men in that ethnic group. The author also includes the prior year…

A synaptic organizing principle for cortical neuronal groups

PubMed Central

Perin, Rodrigo; Berger, Thomas K.; Markram, Henry

2011-01-01

Neuronal circuitry is often considered a clean slate that can be dynamically and arbitrarily molded by experience. However, when we investigated synaptic connectivity in groups of pyramidal neurons in the neocortex, we found that both connectivity and synaptic weights were surprisingly predictable. Synaptic weights follow very closely the number of connections in a group of neurons, saturating after only 20% of possible connections are formed between neurons in a group. When we examined the network topology of connectivity between neurons, we found that the neurons cluster into small world networks that are not scale-free, with less than 2 degrees of separation. We found a simple clustering rule where connectivity is directly proportional to the number of common neighbors, which accounts for these small world networks and accurately predicts the connection probability between any two neurons. This pyramidal neuron network clusters into multiple groups of a few dozen neurons each. The neurons composing each group are surprisingly distributed, typically more than 100 μm apart, allowing for multiple groups to be interlaced in the same space. In summary, we discovered a synaptic organizing principle that groups neurons in a manner that is common across animals and hence, independent of individual experiences. We speculate that these elementary neuronal groups are prescribed Lego-like building blocks of perception and that acquired memory relies more on combining these elementary assemblies into higher-order constructs. PMID:21383177

Temperature control during therapeutic moderate whole-body hypothermia for neonatal encephalopathy.

PubMed

Strohm, B; Azzopardi, D

2010-09-01

The precision of temperature control achieved in clinical practice during therapeutic hypothermia in neonates has not been described. The hourly rectal temperature recordings from 17 infants treated with servo controlled and an equal number treated with manually adjusted cooling equipment were examined. The target rectal temperature for all infants is 33.5 degrees C for 72 h. During 6 to 72 h after start of cooling, the mean (95% CI, variance) of the averaged rectal temperatures was 33.6 degrees C (95% CI 33.4 degrees C to 33.8 degrees C, 0.1 degrees C) in the manually adjusted group and 33.4 degrees C (95% CI 33.3 degrees C to 33.5 degrees C, 0.04 degrees C) in the servo controlled group (means, p=0.08; equality of variance, p=0.03). The variance was also significantly different between infant groups during 1 to 5 h after start of cooling, p=0.01, but not during rewarming. The rectal temperature can be maintained close to the target temperature with either manually adjusted or servo controlled equipment, but there is less temperature variability with the servo controlled system in use in the UK.

Perceptual uniformity of commonly used color spaces

NASA Astrophysics Data System (ADS)

Avanaki, Ali; Espig, Kathryn; Kimpe, Tom; Xthona, Albert; Marchessoux, Cedric; Rostang, Johan; Piepers, Bastian

2014-03-01

Use of color images in medical imaging has increased significantly the last few years. Color information is essential for applications such as ophthalmology, dermatology and clinical photography. Use of color at least brings benefits for other applications such as endoscopy, laparoscopy and digital pathology. Remarkably, as of today, there is no agreed standard on how color information needs to be visualized for medical applications. This lack of standardization results in large variability of how color images are visualized and it makes quality assurance a challenge. For this reason FDA and ICC recently organized a joint summit on color in medical imaging (CMI). At this summit, one of the suggestions was that modalities such as digital pathology could benefit from using a perceptually uniform color space (T. Kimpe, "Color Behavior of Medical Displays," CMI presentation, May 2013). Perceptually uniform spaces have already been used for many years in the radiology community where the DICOM GSDF standard provides linearity in luminance but not in color behavior. In this paper we quantify perceptual uniformity, using CIE's ΔE2000 as a color distance metric, of several color spaces that are typically used for medical applications. We applied our method to theoretical color spaces Gamma 1.8, 2.0, & 2.2, standard sRGB, and DICOM (correction LUT for gray applied to all primaries). In addition, we also measured color spaces (i.e., native behavior) of a high-end medical display (Barco Coronis Fusion 6MP DL, MDCC-6130), and a consumer display (Dell 1907FP). Our results indicate that sRGB & the native color space on the Barco Coronis Fusion exhibit the least non-uniformity within their group. However, the remaining degree of perceptual non-uniformity is still significant and there is room for improvement.

Results From the Physics of Colloids Experiment on ISS

NASA Technical Reports Server (NTRS)

Weitz, David; Bailey, Arthur; Manley, Suliana; Prasad, Vikram; Christianson, Rebecca; Sankaran, Subramanian; Doherty, Michael; Jankovsky, Amy; Lorik, Tibor; Shiley, William

2002-01-01

The Physics of Colloids in Space (PCS) experiment was accommodated within International Space Station (ISS) EXpedite the PRocessing of Experiments to Space Station (EXPRESS) Rack 2 and was remotely operated from early June 2001 until February 2002 from NASA Glenn Research Center's Telescience Support Center (TSC) in Cleveland, Ohio, and from the remote site at Harvard University in Cambridge, Massachusetts. PCS was launched on 4/19/2001 on Space Shuttle STS-100. The experiment was activated on 5/31/2001. The entire experimental setup performed remarkably well, and accomplished 2400 hours of science operations on-orbit. The sophisticated instrumentation in PCS is capable of dynamic and static light scattering from 11 to 169 degrees, Bragg scattering over the range from 10 to 60 degrees, dynamic and static light scattering at low angles from 0.3 to 6.0 degrees, and color imaging. The long duration microgravity environment on the ISS facilitated extended studies on the growth and coarsening characteristics of binary crystals. The de-mixing of the colloid-polymer critical-point sample was also studied as it phase-separated into two phases. Further, aging studies on a col-pol gel, gelation rate studies in extremely low concentration fractal gels over several days, and studies on a glass sample, all provided valuable information. Several exciting and unique aspects of these results are discussed here.

Attrition among Women and Minorities in Earth and Space Science (ESS) Graduate Programs

NASA Astrophysics Data System (ADS)

Alexander, C. J.; Hawthorne, C.; Allen, W. R.; Alvarez, R.; Geisler, J.

2001-05-01

Recent data collected by the American Geological Institute (AGI) indicates that the rate of enrollment of ethnic minorities in the geosciences has steadily declined since the 1980's, and in that time the number of geoscience degrees awarded to ethnic minorities has been fairly steady at less than 1%. Data from the National Science Foundation suggests that only 43 of 186 Universities offering an ESS program have ever graduated an ethnic minority in the history of their program. Factors contributing to these abysmal figures differ for different ethnic-minority groups. We will address institutional obstacles to graduate learning which result in above-normal attrition of ethnic-minorities in ESS graduate programs. The recent studies show an attrition rate of 70% among African American males in ESS graduate programs, while among Hispanic females the attrition rate is only 3%. Studies by sociologists have recently shown that some law schools and medical schools have traits in common with these geoscience departments in the rates at which degrees are awarded to ethnic minorities. Institutional barriers encountered by ethnic minorities in graduate schools may take many forms, but can also be as simple as a lack of community support. In the 1990's the California Institute of Technology (Caltech) made a commitment to the retention of women in their graduate and undergraduate schools. Their program included mentoring, focussed tutoring, self-esteem support groups, and other retention efforts. Under this program, the attrition rate of women has dramatically slowed. In this paper, we will discuss the AGI data, the program instituted by Caltech, possible causes of attrition among populations of Hispanic, and African American males and females, as well as potential programs to address these problems. We will also present, from the nationwide study, data on geoscience departments which have been relatively successful at retaining and graduating ethnic minorities in Earth and Space Sciences. The AGI Report on the Status of [U.S.] Academic Geoscience Departments is available online at the URL listed below.

Synthesis and Characterization of Polyether Adducts of Barium and Strontium Carboxylates and Their Use in the Formation of MTiO(3) Films.

PubMed

Wojtczak, William A.; Atanassova, Paolina; Hampden-Smith, Mark J.; Duesler, Eileen

1996-11-20

The synthesis, characterization, and reactivity of new polyether adducts of strontium and barium carboxylates of general composition M(O(2)CCF(3))(n)()(L) (M = Ba, L = 15-crown-5, (1); M = Ba (2), Sr (3), respectively, with L = tetraglyme are reported. The compounds were synthesized by reaction of BaCO(3) or MH(2) (M = Sr or Ba) with organic acids in the presence of the polyether ligands. These compounds have been characterized by IR and (13)C and (1)H NMR spectroscopies, elemental analyses, and thermogravimetric analysis. The species Ba(2)(O(2)CCF(3))(4)(15-crown-5)(2) (1) and [Ba(2)(O(2)CCF(3))(4)(tetraglyme)](infinity) (2), were also characterized by single-crystal X-ray diffraction. Ba(2)(O(2)CCF(3))(4)(15-crown-5)(2) (1) crystallizes in the orthorhombic space group Cccm with cell dimensions of a = 13.949(1) Å, b = 19.376(2) Å, c = 16.029(1) Å, and Z = 8. [Ba(2)(O(2)CCF(3))(4)(tetraglyme)](infinity) (2) crystallizes in the monoclinic space group C2/c with cell dimensions of a = 12.8673(12) Å, b = 16.6981(13) Å, c = 15.1191(12) Å, beta = 99.049(8) degrees, and Z = 4. Compounds 1-3 thermally decompose at high temperatures in the solid state to give MF(2). However, solutions of compounds 1-3 dissolved in ethanol with Ti(O-i-Pr)(4) give crystalline perovskite phase MTiO(3) films, or in the case of mixtures of 2 and 3, Ba(1)(-)(x)()Sr(x)()TiO(3) films below 600 degrees C when spin coated onto silicon substrates and thermally treated. The crystallinity, purity, and elemental composition of the films was determined by glancing angle X-ray diffraction and Auger electron spectroscopy.

Viable spore counts in biological controls pre-sterilization.

PubMed

Brusca, María I; Bernat, María I; Turcot, Liliana; Nastri, Natalia; Nastri, Maria; Rosa, Alcira

2005-01-01

The aim of the present study was to evaluate the total count of viable spores in standardized inoculated carriers pre-sterilization. Samples of "Bacterial Spore Sterilization Strip" (R Biological Laboratories) (well before their expiry date) were divided into Group A (B. subtilis) and Group B (B. stearothermophylus). Twenty-four strips were tested per group. The strips were minced in groups of three, placed in chilled sterile water and vortexed for 5 minutes to obtain a homogenous suspension. Ten ml of the homogenous suspension were transferred to two sterile jars, i.e. one jar per group. The samples were then heated in a water bath at 95 degrees C (Group A) or 80 degrees C (Group B) for 15 minutes and cooled rapidly in an ice bath at 0- 4 degrees C during 15 minutes. Successive dilutions were performed until a final aliquot of 30 to 300 colony-forming units (CFU) was obtained. The inoculums were placed in Petri dishes with culture medium (soy extract, casein agar adapted for spores, melted and cooled to 45-50 degrees C) and incubated at 55 degrees C or 37 degrees C. Statistical analysis of the data was performed. A larger number of spores were found at 48 hours than at 24 hours. However, this finding did not hold true for all the groups. The present results show that monitoring viable spores pre-sterilization would guarantee the accuracy of the data. Total spore counts must be within 50 and 300% of the number of spores indicated in the biological control. The procedure is essential to guarantee the efficacy of the biological control.

Space Radar Image of Wadi Kufra, Libya

NASA Image and Video Library

1998-04-14

The ability of a sophisticated radar instrument to image large regions of the world from space, using different frequencies that can penetrate dry sand cover, produced the discovery in this image: a previously unknown branch of an ancient river, buried under thousands of years of windblown sand in a region of the Sahara Desert in North Africa. This area is near the Kufra Oasis in southeast Libya, centered at 23.3 degrees north latitude, 22.9 degrees east longitude. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar when it flew aboard the space shuttle Endeavour on its 60th orbit on October 4, 1994. This SIR-C image reveals a system of old, now inactive stream valleys, called "paleodrainage systems, http://photojournal.jpl.nasa.gov/catalog/PIA01310

Comparative cross-sectional study of masticatory performance and mastication predominance for patients with missing posterior teeth.

PubMed

Iwashita, Hayato; Tsukiyama, Yoshihiro; Kori, Hidehiro; Kuwatsuru, Rika; Yamasaki, Yo; Koyano, Kiyoshi

2014-10-01

Missing posterior teeth can decrease masticatory function and cause horizontal mastication deviation, i.e., mastication predominance. Mastication predominance may lead to abnormal tooth attrition and temporomandibular disorders. This study evaluated masticatory performance and mastication predominance in patients with missing posterior teeth to investigate effects of missing posterior teeth on masticatory performance and mastication predominance. Thirty volunteers with normal dentition (control group), 30 patients with unilateral missing posterior teeth (unilateral group), and 23 patients with bilateral missing posterior teeth (bilateral group) participated. Gummy jellies were used to evaluate participants' masticatory performance, and electromyography was used to assess the degree of mastication predominance. Chewing gums, gummy jellies, and peanuts were used as foods of various hardnesses for evaluating mastication predominance. Compared with the control group, masticatory performance did not differ in the unilateral group but was significantly decreased in the bilateral group. With chewing gum and gummy jellies, the degree of mastication predominance was significantly increased in both unilateral and bilateral groups than the control group. With peanuts, the degree of mastication predominance was significantly increased in the unilateral group than the control group. Although masticatory performance was not decreased in the unilateral group, the degree of mastication predominance was increased. Decreased masticatory performance was observed in the bilateral group, and for foods with normal hardness and soft foods, the degree of mastication predominance was increased. These results suggested that mastication predominance should be considered in the recovery of masticatory performance in patients with missing posterior teeth. Copyright © 2014 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Foot kinematics during a bilateral heel rise test in participants with stage II posterior tibial tendon dysfunction.

PubMed

Houck, Jeff R; Neville, Christopher; Tome, Josh; Flemister, A Samuel

2009-08-01

Experimental laboratory study using a cross-sectional design. To compare foot kinematics, using 3-dimensional tracking methods, during a bilateral heel rise between participants with posterior tibial tendon dysfunction (PTTD) and participants with a normal medial longitudinal arch (MLA). The bilateral heel rise test is commonly used to assess patients with PTTD; however, information about foot kinematics during the test is lacking. Forty-five individuals volunteered to participate, including 30 patients diagnosed with unilateral stage II PTTD (mean +/- SD age, 59.8 +/- 11.1 years; body mass index, 29.9 +/- 4.8 kg/m2) and 15 controls (mean +/- SD age, 56.5 +/- 7.7 years; body mass index, 30.6 +/- 3.6 kg/m2). Foot kinematic data were collected during a bilateral heel rise task from the calcaneus (hindfoot), first metatarsal, and hallux, using an Optotrak motion analysis system and Motion Monitor software. A 2-way mixed-effects analysis of variance model, with normalized heel height as a covariate, was used to test for significant differences between the normal MLA and PTTD groups. The patients in the PTTD group exhibited significantly greater ankle plantar flexion (mean difference between groups, 7.3 degrees ; 95% confidence interval [CI]: 5.1 degrees to 9.5 degrees ), greater first metatarsal dorsiflexion (mean difference between groups, 9.0 degrees ; 95% CI: 3.7 degrees to 14.4 degrees ), and less hallux dorsiflexion (mean difference, 6.7 degrees ; 95% CI: 1.7 degrees to 11.8 degrees ) compared to controls. At peak heel rise, hindfoot inversion was similar (P = .130) between the PTTD and control groups. Except for hindfoot eversion/inversion, the differences in foot kinematics in participants with stage II PTTD, when compared to the control group, mainly occur as an offset, not an alteration in shape, of the kinematic patterns.

Role of tumour molecular and pathology features to estimate colorectal cancer risk for first-degree relatives.

PubMed

Win, Aung Ko; Buchanan, Daniel D; Rosty, Christophe; MacInnis, Robert J; Dowty, James G; Dite, Gillian S; Giles, Graham G; Southey, Melissa C; Young, Joanne P; Clendenning, Mark; Walsh, Michael D; Walters, Rhiannon J; Boussioutas, Alex; Smyrk, Thomas C; Thibodeau, Stephen N; Baron, John A; Potter, John D; Newcomb, Polly A; Le Marchand, Loïc; Haile, Robert W; Gallinger, Steven; Lindor, Noralane M; Hopper, John L; Ahnen, Dennis J; Jenkins, Mark A

2015-01-01

To estimate risk of colorectal cancer (CRC) for first-degree relatives of CRC cases based on CRC molecular subtypes and tumour pathology features. We studied a cohort of 33,496 first-degree relatives of 4853 incident invasive CRC cases (probands) who were recruited to the Colon Cancer Family Registry through population cancer registries in the USA, Canada and Australia. We categorised the first-degree relatives into four groups: 28,156 of 4095 mismatch repair (MMR)-proficient probands, 2302 of 301 MMR-deficient non-Lynch syndrome probands, 1799 of 271 suspected Lynch syndrome probands and 1239 of 186 Lynch syndrome probands. We compared CRC risk for first-degree relatives stratified by the absence or presence of specific tumour molecular pathology features in probands across each of these four groups and for all groups combined. Compared with first-degree relatives of MMR-proficient CRC cases, a higher risk of CRC was estimated for first-degree relatives of CRC cases with suspected Lynch syndrome (HR 2.06, 95% CI 1.59 to 2.67) and with Lynch syndrome (HR 5.37, 95% CI 4.16 to 6.94), but not with MMR-deficient non-Lynch syndrome (HR 1.04, 95% CI 0.82 to 1.31). A greater risk of CRC was estimated for first-degree relatives if CRC cases were diagnosed before age 50 years, had proximal colon cancer or if their tumours had any of the following: expanding tumour margin, peritumoral lymphocytes, tumour-infiltrating lymphocytes or synchronous CRC. Molecular pathology features are potentially useful to refine screening recommendations for first-degree relatives of CRC cases and to identify which cases are more likely to be caused by genetic or other familial factors. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Explaining Gibbsean phase space to second year students

NASA Astrophysics Data System (ADS)

Vesely, Franz J.

2005-03-01

A new approach to teaching introductory statistical physics is presented. We recommend making extensive use of the fact that even systems with a very few degrees of freedom may display chaotic behaviour. This permits a didactic 'bottom-up' approach, starting out with toy systems whose phase space may be depicted on a screen or blackboard, then proceeding to ever higher dimensions in Gibbsean phase space.

Demonstration of Self-Training Autonomous Neural Networks in Space Vehicle Docking Simulations

NASA Technical Reports Server (NTRS)

Patrick, M. Clinton; Thaler, Stephen L.; Stevenson-Chavis, Katherine

2006-01-01

Neural Networks have been under examination for decades in many areas of research, with varying degrees of success and acceptance. Key goals of computer learning, rapid problem solution, and automatic adaptation have been elusive at best. This paper summarizes efforts at NASA's Marshall Space Flight Center harnessing such technology to autonomous space vehicle docking for the purpose of evaluating applicability to future missions.

Root resorption of maxillary incisors retracted with and without skeletal anchorage.

PubMed

Barros, Sérgio Estelita; Janson, Guilherme; Chiqueto, Kelly; Baldo, Vitor Oliveira; Baldo, Taiana Oliveira

2017-02-01

Our objective was to compare root resorption degree of the maxillary central incisors retracted with and without skeletal anchorage. This nonrandomized historical control study included 37 patients requiring maximum anterior retraction and treated with extraction of 2 maxillary premolars. Group 1 consisted of 22 patients (11 male, 11 female) in whom anterior retraction was performed without skeletal anchorage, and group 2 included 15 patients (3 male, 12 female) treated with skeletally anchored anterior retraction. Periapical radiographs were used to evaluate root resorption degree by a scoring system. The groups were compared regarding the resorption score and resorption degree distribution with the Mann-Whitney U test, chi-square test, and Z test on proportions. There was no statistically significant intergroup difference regarding root resorption, but the number of patients with severe and extreme root resorption degrees was significantly greater in group 2. Although the root resorption degree of the skeletal anchorage group was not significantly different from the group without skeletal anchorage, the number of patients with severe to extreme resorption in the first group was significantly greater. Therefore, careful clinical monitoring of skeletally anchored anterior retraction is needed, especially when there are known root resorption predisposing factors. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Effects of Oxygen Element and Oxygen-Containing Functional Groups on Surface Wettability of Coal Dust with Various Metamorphic Degrees Based on XPS Experiment

PubMed Central

Zhou, Gang; Xu, Cuicui; Cheng, Weimin; Zhang, Qi; Nie, Wen

2015-01-01

To investigate the difference of surface oxygen element and oxygen-containing functional groups among coal dusts with different metamorphic degrees and their influence on surface wettability, a series of X-ray photoelectron spectroscopy experiments on 6 coal samples are carried out. The result demonstrates that the O/C ratio of coal surface shows an overall increasing trend compared with the result of its elements analysis. As the metamorphic degree increases, the O/C ratio on the surface gradually declines and the hydrophilic groups tend to fall off from coal surface. It could be found that different coals show different surface distributions of carboxyl and hydroxyl which are considered as the greatest promoter to the wettability of coal surface. With the change of metamorphic degree, the distribution of ether group is irregular while the carbonyl distribution keeps stable. In general, as the metamorphic degree goes higher, the content of oxygen-containing polar group tends to reduce. According to the measurement results, the contact angle is negatively related to the content of oxygen element, surface oxygen, and polar groups. In addition, compared with surface oxygen content, the content of oxygen-containing polar group serves as a more reasonable indicator of coal dust wettability. PMID:26257980

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

Zhou, Chen; Pinkerton, Frederick E.; Herbst, Jan F.

New magnetic materials containing cerium, iron, and small additions of a third element are disclosed. These materials comprise compounds Ce(Fe.sub.12-xM.sub.x) where x=1-4, having the ThMn.sub.12 tetragonal crystal structure (space group I4/mmm, #139). Compounds with M=B, Al, Si, P, S, Sc, Co, Ni, Zn, Ga, Ge, Zr, Nb, Hf, Ta, and W are identified theoretically, and one class of compounds based on M=Si has been synthesized. The Si cognates are characterized by large magnetic moments (4.pi.M.sub.s greater than 1.27 Tesla) and high Curie temperatures (264.ltoreq.T.sub.c.ltoreq.305.degree. C.). The Ce(Fe.sub.12-xM.sub.x) compound may contain one or more of Ti, V, Cr, and Mo inmore » combination with an M element. Further enhancement in T.sub.c is obtained by nitriding the Ce compounds through heat treatment in N.sub.2 gas while retaining the ThMn.sub.12 tetragonal crystal structure; for example CeFe.sub.10Si.sub.2N.sub.1.29 has T.sub.c=426.degree. C.« less

Combined dietary and exercise intervention for control of serum cholesterol in the workplace

NASA Technical Reports Server (NTRS)

Angotti, C. M.; Chan, W. T.; Sample, C. J.; Levine, M. S.

2000-01-01

PURPOSE: To elucidate a potential combined dietary and exercise intervention affect on cardiovascular risk reduction of the National Aeronautics and Space Administration Headquarters employees. DESIGN: A nonexperimental, longitudinal, clinical-chart review study (1987 to 1996) of an identified intervention group and a reference (not a control) group. SETTING: The study group worked in an office environment and participated in the annual medical examinations. SUBJECTS: An intervention group of 858 people with initially elevated serum cholesterol, and a reference group of 963 people randomly sampled from 10% of the study group. MEASURES: Serum cholesterol data were obtained for both groups, respectively, from pre- and postintervention and annual examinations. The reference group was adjusted by statistical exclusion of potential intervention participants. Regression equations (cholesterol vs. study years) for the unadjusted/adjusted reference groups were tested for statistical significance. INTERVENTION: An 8-week individualized, combined dietary and exercise program was instituted with annual follow-ups and was repeated where warranted. RESULTS: Only the unadjusted (but not the adjusted) reference group with initial mean total serum cholesterol levels above 200 mg/dL shows a significant 9-year decline trend and significant beta coefficient tests. An intervention effect is suggested. Mean high density lipoprotein cholesterol rose slightly in the intervention group but was maintained in the reference group. CONCLUSION: With potential design limitations, the NASA intervention program focusing on a high risk group may be associated to some degree, if not fully, with an overall cardiovascular risk profile improvement.

L'espace articulaire de la Robotique Industrielle est un espace vectorielIndustrial Robotics joint space is a vector space

NASA Astrophysics Data System (ADS)

Tondu, Bertrand

2003-05-01

The mathematical modelling of industrial robots is based on the vectorial nature of the n-dimensional joint space of the robot, defined as a kinematic chain with n degrees of freedom. However, in our opinion, the vectorial nature of the joint space has been insufficiently discussed in the literature. We establish the vectorial nature of the joint space of an industrial robot from the fundamental studies of B. Roth on screws. To cite this article: B. Tondu, C. R. Mecanique 331 (2003).

Static stability and control effectiveness of a parametric launch vehicle

NASA Technical Reports Server (NTRS)

Ellis, R. R.; Gamble, M.

1972-01-01

An investigation is reported to determine the static aerodynamic characteristics of a space shuttle parametric launch configuration. The orbiter control surfaces were deflected to obtain the control effectiveness for use in launch vehicle control studies. Experimental data were obtained for Mach number from 0.6 to 4.96, angles of attack from minus 10 to plus 10 degrees and angles of sideslip from minus six to six degrees at zero degrees angle of attack.

Earth Observations taken by the Expedition 17 Crew

NASA Image and Video Library

2008-09-10

ISS017-E-015751 (10 Sept. 2008) --- This picture of Hurricane Ike from earlier today was downlinked by the crew of the International Space Station, flying 220 statute miles above Earth. The center of the hurricane was near 23.8 degrees north latitude and 85.3 degrees west longitude, moving 300 degrees at 7 nautical miles per hour. The sustained winds were 80 nautical miles per hour with gusts to 100 nautical miles per hour and forecast to intensify.

Results of tests of a 0.010- and 0.015-scale models of space shuttle orbiter configurations 3 and 3A in the Ames Research Center 3.5 foot hypersonic wind tunnel (OA23)

NASA Technical Reports Server (NTRS)

Dziubala, T. J.; Milam, M. D.; Cleary, J. W.; Mellenthin, J. A.

1974-01-01

Longitudinal and lateral-directional stability and control characteristics were evaluated at Mach numbers of 5.3, 7.3 and 10.3 at angles of attack up to 50 degrees with Beta = 0 degrees and, for a few cases, Beta = 5 degrees. Component force data, fuselage base pressures and shadowgraph patterns were recorded.

Inhibition of particulate debris-induced osteolysis by alendronate in a rat model.

PubMed

Thadani, Peter J; Waxman, Bryan; Sladek, Eduard; Barmada, Riad; Gonzalez, Mark H

2002-01-01

A rat model was used to study the efficacy of alendronate therapy in inhibition of particle-induced periprosthetic osteolysis. A prosthesis was simulated by inserting a cylindrical polymethylmethacrylate plug into the distal femur of 24 rats allowing the plug to communicate with the joint space. Intra-articular injections of irregularly-shaped ultra-high molecular weight polyethylene particles of 20-200 pm in diameter were administered at 2-week intervals. The rats were randomized into two groups (n=12 each). Group A rats received twice weekly subcutaneous injections of alendronate sodium while group B rats received injections of saline vehicle only. At 10 weeks all rats were sacrificed. The distal femurs were harvested and axial sections were prepared for histologic analysis. Each section was graded on a scale of 1-4, quantifying the degree of osteolysis surrounding the polymethylmethacrylate plug. Microscopic examination showed a significant (P<.0001) difference in the amount of periprosthetic bone. Femurs from group A treated with alendronate demonstrated mostly normal or near-normal periprosthetic trabeculations, whereas femurs from group B treated with saline showed extensive bone resorption. There was no qualitative difference in the inflammatory cellular response between the groups. This study established the ability of alendronate to inhibit the osteoclastic-mediated osteolysis around joint implants.

Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

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

Ryan, K.M.

1990-12-01

The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26[degree]C and downshifted 30-26-30[degree]C) and females (constant 30[degree]C and upshifted 26-30-26[degree]C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26[degree]C group and 93% males from the downshifted group. 100% females resulted from both the constant 30[degree]C group and the upshifted group. Turtles hatching from eggsmore » incubated constantly at 26[degree]C were significantly larger than hatchlings from eggs incubated at a constant 30[degree]C or downshifted. Hatchlings were raised in individual aquaria at 25[degree]C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30[degree]C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.« less

Pre-separation storage of whole blood: the effect of temperature on red cell 2,3-diphosphoglycerate and myeloperoxidase in plasma.

PubMed

Knutson, F; Lööf, H; Högman, C F

1999-10-01

Although whole blood intended for component preparation is commonly left to cool at ambient temperature, knowledge is insufficient concerning what effects this may have on red blood cell (RBC) quality, in particular after a prolonged hold. Whole blood collected in CPD was incubated at 20 degrees C and 28 degrees C for 6 h designed as a paired study. Blood components were prepared and the red blood cell concentrates (RBCs) were stored for 28 days at 4 degrees C +/- 2 degrees C. Blood gases, pH, glucose, lactate, adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG) and plasma myeloperoxidase (MPO) were investigated. After 6 h the 2,3-DPG concentrations had lowered to 88% (20 degrees C) and 54% (28 degrees C) of initial levels, respectively. The difference was significant and was maintained for 28 days, although, at low levels from day 7 (28 degrees C) and day 14 (20 degrees C) of storage. ATP was maintained at the initial level in both groups during the first 6 h of storage but after component separation the levels were significantly higher in the 28 degrees C group during the first 5 days. The release of myeloperoxidase (MPO) was significantly higher in the non-cooled group than in the cooled group. Pre-separation holding for 6 h of whole blood at temperatures of 28 degrees C causes a great and rapid loss of 2,3-DPG and considerable formation of acid metabolites resulting in clearly subnormal 2,3-DPG levels even on day 1. Active pre-separation cooling to 20 degrees C is to be recommended.

Work-Based Research Degrees: Systematic Cultivation through a University-Industry Network Space

ERIC Educational Resources Information Center

Sense, Andrew J.

2016-01-01

The purpose of this paper is to expound on an innovative approach to cultivating work-based Doctorates and Masters of Philosophy degrees, which involves close collaboration between industry organisations and a tertiary institution. This paper also reports on an examination of the programme's structural ability to help develop the learning…

Earth Observations taken by the Expedition 10 crew

NASA Image and Video Library

2005-01-11

ISS010-E-12743 (11 January 2005) --- One of a series of post-tsunami digital still images photographed by the Expedition 10 crew aboard the International Space Station. This image, recorded on January 11, 2005 and centered at 7.61 degrees north latitude and 99.06 degrees east longitude, features Ko Lanta Yai (Thailand)

Earth Observations taken by the Expedition 10 crew

NASA Image and Video Library

2005-01-11

ISS010-E-12727 (11 January 2005) --- One of a series of post-tsunami digital still images photographed by the Expedition 10 crew aboard the International Space Station. This image, recorded on January 11, 2005 and centered at 7.61 degrees north latitude and 99.06 degrees east longitude, features Ko Lanta Yai (Thailand)

Earth Observations taken by the Expedition 10 crew

NASA Image and Video Library

2005-01-11

ISS010-E-12736 (11 January 2005) --- One of a series of post-tsunami digital still images photographed by the Expedition 10 crew aboard the International Space Station. This image, recorded on January 11, 2005 and centered at 7.83 degrees north latitude and 98.34 degrees east longitude, shows Phuket (Thailand)

Earth Observation

NASA Image and Video Library

2013-08-29

ISS036-E-038117 (29 Aug. 2013) --- One of the Expedition 36 crew members aboard the Earth-orbiting International Space Station photographed massive smoke plumes from the California wildfires. When this image was exposed on Aug. 29, the orbital outpost was approximately 220 miles above a point located at 38.6 degrees north latitude and 123.2 degrees west longitude.

Earth Observation

NASA Image and Video Library

2013-08-29

ISS036-E-038114 (29 Aug. 2013) --- One of the Expedition 36 crew members aboard the Earth-orbiting International Space Station photographed massive smoke plumes from the California wildfires. When this image was exposed on Aug. 29, the orbital outpost was approximately 220 miles above a point located at 38.6 degrees north latitude and 123.3 degrees west longitude.

Earth observation taken by the Expedition 35 crew

NASA Image and Video Library

2013-04-18

ISS035-E-023422 (18 April 2013) --- One of the Expedition 35 crew members aboard the Earth-orbiting International Space Station photographed this night image of Tripoli, Libya on April 18, 2013. The spacecraft was orbiting approximately 215 miles above a point centered at 32.3 degrees north latitude and 11.8 degrees east longitude.

46 CFR 76.27-15 - Operation and installation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... audible alarm in the engine room. (b) The detectors, the detecting cabinet and alarms shall be of an approved type. (c) In general, the detectors, shall be rated not lower than 135 degrees F. and not higher than 165 degrees F. However, in spaces where a high ambient temperature may be expected, detectors...

46 CFR 76.27-15 - Operation and installation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... audible alarm in the engine room. (b) The detectors, the detecting cabinet and alarms shall be of an approved type. (c) In general, the detectors, shall be rated not lower than 135 degrees F. and not higher than 165 degrees F. However, in spaces where a high ambient temperature may be expected, detectors...

46 CFR 76.27-15 - Operation and installation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... audible alarm in the engine room. (b) The detectors, the detecting cabinet and alarms shall be of an approved type. (c) In general, the detectors, shall be rated not lower than 135 degrees F. and not higher than 165 degrees F. However, in spaces where a high ambient temperature may be expected, detectors...

46 CFR 76.27-15 - Operation and installation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... audible alarm in the engine room. (b) The detectors, the detecting cabinet and alarms shall be of an approved type. (c) In general, the detectors, shall be rated not lower than 135 degrees F. and not higher than 165 degrees F. However, in spaces where a high ambient temperature may be expected, detectors...

Entanglement for All Quantum States

ERIC Educational Resources Information Center

de la Torre, A. C.; Goyeneche, D.; Leitao, L.

2010-01-01

It is shown that a state that is factorizable in the Hilbert space corresponding to some choice of degrees of freedom becomes entangled for a different choice of degrees of freedom. Therefore, entanglement is not a special case but is ubiquitous in quantum systems. Simple examples are calculated and a general proof is provided. The physical…

Earth Observation taken by the Expedition 29 crew

NASA Image and Video Library

2011-09-16

ISS029-E-005352 (16 Sept. 2011) --? One of the Expedition 29 crew members aboard the International Space Station, flying at an altitude of approximately 220 miles, took this night time picture showing Africa's Congo coast, clouds, airglow and Earth's terminator. Nadir coordinates are 5.32 degrees south latitude and 12.86 degrees east longitude.

Field evaluation and assessment of thermal energy storage for residential space heating

NASA Astrophysics Data System (ADS)

Hersh, H. N.

1982-02-01

A data base was developed based on two heating seasons and 45 test and 30 control homes in Maine and Vermont. Based on first analysis of monitored temperatures and electrical energy used for space heating, fuel bills and reports of users and utilities, the technical performance of TES ceramic and hydronic systems is deemed to be technically satisfactory and there is a high degree of customer acceptance and positive attitudes towards TES. Analysis of house data shows a high degree of variability in electric heat energy demand for a given degree-day. An analysis is underway to investigate relative differences in the efficiency of electricity utilization of storage and direct heating devices. The much higher price of storge systems relative to direct systems is an impediment to market penetration. A changing picture of rate structures may encourage direct systems at the expense of storage systems.

Annular suspension and pointing system with controlled DC electromagnets

NASA Technical Reports Server (NTRS)

Vu, Josephine Lynn; Tam, Kwok Hung

1993-01-01

The Annular Suspension and Pointing System (ASPS) developed by the Flight System division of Sperry Corporation is a six-degree of freedom payload pointing system designed for use with the space shuttle. This magnetic suspension and pointing system provides precise controlled pointing in six-degrees of freedom, isolation of payload-carrier disturbances, and end mount controlled pointing. Those are great advantages over the traditional mechanical joints for space applications. In this design, we first analyzed the assumed model of the single degree ASPS bearing actuator and obtained the plant dynamics equations. By linearizing the plant dynamics equations, we designed the cascade and feedback compensators such that a stable and satisfied result was obtained. The specified feedback compensator was computer simulated with the nonlinearized plant dynamics equations. The results indicated that an unstable output occurred. In other words, the designed feedback compensator failed. The failure of the design is due to the Taylor's series expansion not converging.

Space shuttle: Longitudinal and lateral aerodynamic characteristics of the 0.0035-scale GD/C aerospace booster (B-15B-1)

NASA Technical Reports Server (NTRS)

Debevoise, J. M.; Mcginnis, R. F.

1972-01-01

Force tests on a 0.0035-scale model of the General Dynamics/Convair space shuttle B-15B-1 booster were conducted in the MSFC trisonic wind tunnel during February and March 1971. Longitudinal and lateral characteristics were obtained at Mach numbers from 0.6 to 4.96. The configuration tested had a low delta wing, all-movable canard controls of delta planform, and a single vertical tail. Most of the test was devoted to obtaining data relevant to the transition from atmospheric reentry to subsonic cruise. In that portion of the test the angles of attack ranged from 6 degrees to 60 degrees, and yaw runs were made at angles of attack of 15 and 35 degrees. The rest of the test was devoted to obtaining booster-alone buildup data relevant to the launch phase. For the launch phase, the Mach number range was from 0.6 to 2.0, the angles of attack were from -10 to +10 degrees, and yaw runs were made at zero angle of attack.

Resistive-heating or forced-air warming for the prevention of redistribution hypothermia.

PubMed

De Witte, Jan L; Demeyer, Caroline; Vandemaele, Els

2010-03-01

We evaluated the efficacy of resistive-heating or forced-air warming versus no prewarming, applied before induction of anesthesia for prevention of hypothermia. Twenty-seven patients scheduled for laparoscopic colorectal surgery were randomized into 1 of 3 groups: no prewarming; 30 minutes of prewarming with a carbon fiber total body cover at 42 degrees C; or 30 minutes of preoperative forced-air warming at 42 degrees C. The forced-air warming cover excluded the shoulders, ankles, and feet. The prewarming period was exactly 30 minutes. At the 31st minute, a total IV anesthesia technique was initiated, and all patients were actively warmed with a lithotomy blanket. Tympanic and distal esophageal temperatures were measured. Categorical data were analyzed using chi(2) test, and continuous data were analyzed with analysis of variance. P <0.05 was considered statistically significant. The mean esophageal temperatures differed significantly between the control and the carbon fiber group from 40 to 90 minutes of anesthesia. After 50 minutes of anesthesia, the mean esophageal temperatures in the control, carbon fiber, and forced-air groups were 35.9 degrees C +/- 0.3 degrees C, 36.5 degrees C +/- 0.4 degrees C, and 36.2 degrees C +/- 0.3 degrees C, respectively. No statistically significant difference was found between the forced-air and control groups. After 30 minutes of prewarming with resistive heating, patients had an esophageal temperature that was significantly higher than the control group. Prewarming should be considered part of the anesthetic management when patients are at risk for postoperative hypothermia.

Special Relativity Kinematics with Anisotropic Propagation of Light and Correspondence Principle

NASA Astrophysics Data System (ADS)

Burde, Georgy I.

2016-12-01

The purpose of the present paper is to develop kinematics of the special relativity with an anisotropy of the one-way speed of light. As distinct from a common approach, when the issue of anisotropy of the light propagation is placed into the context of conventionality of distant simultaneity, it is supposed that an anisotropy of the one-way speed of light is due to a real space anisotropy. In that situation, some assumptions used in developing the standard special relativity kinematics are not valid so that the "anisotropic special relativity" kinematics should be developed based on the first principles, without refereeing to the relations of the standard relativity theory. In particular, using condition of invariance of the interval between two events becomes unfounded in the presence of anisotropy of space since the standard proofs drawing the interval invariance from the invariance of equation of light propagation are not valid in that situation. Instead, the invariance of the equation of light propagation (with an anisotropy of the one-way speed of light incorporated), which is a physical law, should be taken as a first principle. A number of other physical requirements, associativity, reciprocity and so on are satisfied by the requirement that the transformations between the frames form a group. Finally, the correspondence principle is to be satisfied which implies that the coordinate transformations should turn into the Galilean transformations in the limit of small velocities. The above formulation based on the invariance and group property suggests applying the Lie group theory apparatus which includes the following steps: constructing determining equations for the infinitesimal group generators using the invariance condition; solving the determining equations; specifying the solutions using the correspondence principle; defining the finite transformations by solving the Lie equations; relating the group parameter to physical parameters. The transformations derived in such a way, as distinct from the transformations derived in the context of conventionality of distant simultaneity, cannot be converted into the standard Lorentz transformations by a coordinate (synchrony) change. The anisotropic nature of the presented transformations manifests itself in that they do not leave the interval invariant but only provide the conformal invariance of the interval. The relations that represent measurable effects include the conformal factor which depends on the relative velocity of the frames and the anisotropy degree. It is important to note the use of the correspondence principle as a heuristic principle which allows to relate the conformal factor to the anisotropy degree and thus completely specify the transformations and observable quantities.

Comparison of Successful Spinal Needle Placement Between Crossed-Leg Sitting Position and Traditional Sitting Position in Patients Undergoing Urology Surgery

PubMed Central

Manggala, Sidharta K.; Tantri, Aida R.; Satoto, Darto

2016-01-01

Background The patient’s position during spinal anesthesia administration plays a major role in the success of spinal needle insertion into the subarachnoid space. The traditional sitting position (TSP) is the standard position for spinal anesthesia administration, but the success rate for spinal anesthesia administration in the TSP is still quite low. The crossed-leg sitting position (CLSP) is one of the alternative positions for the administration of spinal anesthesia, which can increase the degree of lumbar flexion. Objectives This study aimed to compare successful spinal needle placement to patients in the CLSP and patients in the TSP prior to undergoing urology surgery. Methods This study was a non-blinded, randomized controlled trial in patients undergoing spinal anesthesia for urologic procedures from March-October, 2015 in the central national hospital Dr. Cipto Mangunkusumo, Indonesia. After obtaining approval from the FMUI – RSCM (Faculty of Medicine Universitas Indonesia – Rumah Sakit Dr. Cipto Mangunkusumo) Ethical Committee and informed consent from patients, 211 subjects were allocated into two groups: the CLSP group (n = 105) and the TSP group (n = 106). The proportion of successful spinal needle placement to the subarachnoid space, ease of landmark palpation, and the number of needle-bone contacts in both groups were then assessed and analyzed. Results The rate of first-time successful spinal needle insertion was not significantly different between the CLSP and TSP groups (62.9% versus 55.7%, P > 0.05). Ease of landmark palpation in the CLSP group was not significantly different from that in the TSP group (86.7% versus 76.4%, P > 0.05). The number of needle-bone contacts in both groups were not significantly different (P > 0.05). The complication rates were similar in both groups. Conclusions The rate of successful spinal needle placement in the CLSP group was not significantly different from that in the TSP group in patients undergoing urology surgery. The CLSP can be used as an alternative sitting position for administration of spinal anesthesia. PMID:27843785

Thirsk in JPM

NASA Image and Video Library

2009-06-06

ISS020-E-007147 (6 June 2009) --- Canadian Space Agency astronaut Robert Thirsk, Expedition 20 flight engineer, performs an insertion of urine samples into the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) study in the Japanese Kibo laboratory of the International Space Station.

Thirsk in JPM

NASA Image and Video Library

2009-06-06

ISS020-E-007140 (6 June 2009) --- Canadian Space Agency astronaut Robert Thirsk, Expedition 20 flight engineer, performs an insertion of urine samples into the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) study in the Japanese Kibo laboratory of the International Space Station.

The acoustic analysis of tone differentiation as a means for assessing tone production in speakers of Cantonese

NASA Astrophysics Data System (ADS)

Barry, Johanna G.; Blamey, Peter J.

2004-09-01

This paper reports on a methodology for acoustically analyzing tone production in Cantonese. F0 offset versus F0 onset are plotted for a series of tokens for each of the six tones in the language. These are grouped according to tone type into a set of six ellipses. Qualitative visual observations regarding the degree of differentiation of the ellipses within the tonal space are summarized numerically using two indices, referred to here as Index 1 and Index 2. Index 1 is a ratio of the area of the speaker's tonal space and the average of the areas of the ellipses of the three target tones making up the tonal space. Index 2 is a ratio of the average distance between all six tonal ellipses and the average of the sum of the two axes for all six tone ellipses. Using this methodology, tonal differentiation is compared for three groups of speakers; normally hearing adults; normally hearing children aged from 4-6 years; and, prelinguistically deafened cochlear implant users aged from 4-11 years. A potential conundrum regarding how tone production abilities can outstrip tone perception abilities is explained using the data from the acoustic analyses. It is suggested that young children of the age range tested are still learning to normalize for pitch level differences in tone production. Acoustic analysis of the data thus supports results from tone perception studies and suggests that the methodology is suitable for use in studies investigating tone production in both clinical and research contexts.

Radarsat Antarctic Mapping Project: Antarctic Imaging Campaign 2

NASA Technical Reports Server (NTRS)

2001-01-01

The Radarsat Antarctic Mapping Project is a collaboration between NASA and the Canadian Space Agency to map Antarctica using synthetic aperture radar (SAR). The first Antarctic Mapping Mission (AMM-1) was successfully completed in October 1997. Data from the acquisition phase of the 1997 campaign have been used to achieve the primary goal of producing the first, high-resolution SAR image map of Antarctica. The limited amount of data suitable for interferometric analysis have also been used to produce remarkably detailed maps of surface velocity for a few selected regions. Most importantly, the results from AMM-1 are now available to the general science community in the form of various resolution, radiometrically calibrated and geometrically accurate image mosaics. The second Antarctic imaging campaign occurred during the fall of 2000. Modified from AMM-1, the satellite remained in north looking mode during AMM-2 restricting coverage to regions north of about -80 degrees latitude. But AMM-2 utilized for the first time RADARSAT-1 fine beams providing an unprecedented opportunity to image many of Antarctica's fast glaciers whose extent was revealed through AMM-1 data. AMM-2 also captured extensive data suitable for interferometric analysis of the surface velocity field. This report summarizes the science goals, mission objectives, and project status through the acquisition phase and the start of the processing phase. The reports describes the efforts of team members including Alaska SAR Facility, Jet Propulsion Laboratory, Vexcel Corporation, Goddard Space Flight Center, Wallops Flight Facility, Ohio State University, Environmental Research Institute of Michigan, White Sands Facility, Canadian Space Agency Mission Planning and Operations Groups, and the Antarctic Mapping Planning Group.

The Brazilian research and teaching center in biomedicine and aerospace biomedical engineering.

PubMed

Russomano, T; Falcao, P F; Dalmarco, G; Martinelli, L; Cardoso, R; Santos, M A; Sparenberg, A

2008-08-01

The recent engagement of Brazil in the construction and utilization of the International Space Station has motivated several Brazilian research institutions and universities to establish study centers related to Space Sciences. The Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS) is no exception. The University initiated in 1993 the first degree course training students to operate commercial aircraft in South America (the School of Aeronautical Sciences. A further step was the decision to build the first Brazilian laboratory dedicated to the conduct of experiments in ground-based microgravity simulation. Established in 1998, the Microgravity Laboratory, which was located in the Instituto de Pesquisas Cientificas e Tecnologicas (IPCT), was supported by the Schools of Medicine, Aeronautical Sciences and Electrical Engineering/Biomedical Engineering. At the end of 2006, the Microgravity Laboratory became a Center and was transferred to the School of Engineering. The principal activities of the Microgravity Centre are the development of research projects related to human physiology before, during and after ground-based microgravity simulation and parabolic flights, to aviation medicine in the 21st century and to aerospace biomedical engineering. The history of Brazilian, and why not say worldwide, space science should unquestionably go through PUCRS. As time passes, the pioneering spirit of our University in the aerospace area has become undeniable. This is due to the group of professionals, students, technicians and staff in general that have once worked or are still working in the Center of Microgravity, a group of faculty and students that excel in their undeniable technical-scientific qualifications.

Role Differentiation in Groups: The Relationship Between Instrumental and Expressive Leadership.

ERIC Educational Resources Information Center

Rees, C. Roger; Segal, Mady Wechsler

1984-01-01

Examined the degree of differentiation between instrumental and expressive leadership roles in two natural groups (N=101). Results showed a relatively high degree of leadership role integration with several members of each group fulfilling both instrumental and expressive leadership roles. (LLL)

Gauge fields and ghosts in Rindler space

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

Zhitnitsky, Ariel R.

2010-11-15

We consider a two-dimensional Maxwell system defined on the Rindler space with metric ds{sup 2}=exp(2a{xi}){center_dot}(d{eta}{sup 2}-d{xi}{sup 2}) with the goal to study the dynamics of the ghosts. We find an extra contribution to the vacuum energy in comparison with Minkowski space-time with metric ds{sup 2}=dt{sup 2}-dx{sup 2}. This extra contribution can be traced to the unphysical degrees of freedom (in Minkowski space). The technical reason for this effect to occur is the property of Bogolubov's coefficients which mix the positive- and negative-frequency modes. The corresponding mixture cannot be avoided because the projections to positive-frequency modes with respect to Minkowski timemore » t and positive-frequency modes with respect to the Rindler observer's proper time {eta} are not equivalent. The exact cancellation of unphysical degrees of freedom which is maintained in Minkowski space cannot hold in the Rindler space. In the Becchi-Rouet-Stora-Tyutin (BRST) approach this effect manifests itself as the presence of BRST charge density in L and R parts. An inertial observer in Minkowski vacuum |0> observes a universe with no net BRST charge only as a result of cancellation between the two. However, the Rindler observers who do not ever have access to the entire space-time would see a net BRST charge. In this respect the effect resembles the Unruh effect. The effect is infrared (IR) in nature, and sensitive to the horizon and/or boundaries. We interpret the extra energy as the formation of the ''ghost condensate'' when the ghost degrees of freedom cannot propagate, but nevertheless do contribute to the vacuum energy. Exact computations in this simple two-dimensional model support the claim made in a previous paper [F. R. Urban and A. R. Zhitnitsky, Nucl. Phys. B835, 135 (2010).] that the ghost contribution might be responsible for the observed dark energy in a four-dimensional Friedmann-Lemaitre-Robertson-Walker universe.« less

Design of the annular suspension and pointing system /ASPS/ through decoupling and pole placement. [for Space Shuttle

NASA Technical Reports Server (NTRS)

Kuo, B. C.; Lin, W. C. W.

1980-01-01

A decoupling and pole-placement technique has been developed for the Annular Suspension and Pointing System (ASPS) of the Space Shuttle which uses bandwidths as performance criteria. The dynamics of the continuous-data ASPS allows the three degrees of freedom to be totally decoupled by state feedback through constant gains, so that the bandwidth of each degree of freedom can be independently specified without interaction. Although it is found that the digital ASPS cannot be completely decoupled, the bandwidth requirements are satisfied by pole placement and a trial-and-error method based on approximate decoupling.

Effects of space flight factors on Drosophila.

PubMed

Dubinin, N P; Glembotsky, Y L; Vaulina, E N; Grozdova, T Y; Kamshilova, E M; Ivaschenko, N I; Kholikova, I A; Nechitailo, G S; Mashinsky, A L; Iordanishvili, E K

1973-01-01

Drosophila melanogaster flies of strain D-32 were exposed aboard the Soyuz 10 spaceship. An insert with a nutritional medium and insects was placed in a small on-board thermostat (Biotherm II) providing a constant temperature (24 degrees C +/- 1 degree) for Drosophila development. The frequency of dominant lethals was determined in the females. Dominant, autosomal and sex-linked recessive lethals were estimated in hatching virgin males and females; the time of hatching was rigorously fixed. Sex-linked recessive lethals were related to certain stages of gametogenesis. The 1-5 oocyte stage showed an increased sensitivity to space-flight factors as regards the frequency of both dominant and recessive lethals.

Space shuttle launch vehicle (13 P-OTS) strut support interference effects study in the Rockwell International 7- by 7-foot trisonic wind tunnel (IA68)

NASA Technical Reports Server (NTRS)

Rogge, R. L.

1974-01-01

Strut support interference investigations were conducted on an 0.004-(-) scale representation of the space shuttle launch vehicle in order to determine transonic and supersonic model support interference effects for use in a future exhaust plume effects study. Strut configurations were also tested. Orbiter, external tank, and solid rocket booster pressures were recorded at Mach numbers 0.9, 1.2, 1.5, and 2.0. Angle of attack and angle of sideslip were varied between plus or minus 4 degrees in 2 degree increments. Parametric variations consisted only of the strut configurations.

FAST TRACK COMMUNICATION: Necessary conditions for classical super-integrability of a certain family of potentials in constant curvature spaces

NASA Astrophysics Data System (ADS)

Maciejewski, Andrzej J.; Przybylska, Maria; Yoshida, Haruo

2010-09-01

We formulate the necessary conditions for the maximal super-integrability of a certain family of classical potentials defined in the constant curvature two-dimensional spaces. We give examples of homogeneous potentials of degree -2 on {\\bb E}^2 as well as their equivalents on {\\bb S}^2 and {\\bb H}^2 for which these necessary conditions are also sufficient. We show explicit forms of the additional first integrals which can always be chosen as a polynomial with respect to the momenta and which can be of an arbitrary high degree with respect to the momenta.

Curvature and temperature of complex networks.

PubMed

Krioukov, Dmitri; Papadopoulos, Fragkiskos; Vahdat, Amin; Boguñá, Marián

2009-09-01

We show that heterogeneous degree distributions in observed scale-free topologies of complex networks can emerge as a consequence of the exponential expansion of hidden hyperbolic space. Fermi-Dirac statistics provides a physical interpretation of hyperbolic distances as energies of links. The hidden space curvature affects the heterogeneity of the degree distribution, while clustering is a function of temperature. We embed the internet into the hyperbolic plane and find a remarkable congruency between the embedding and our hyperbolic model. Besides proving our model realistic, this embedding may be used for routing with only local information, which holds significant promise for improving the performance of internet routing.

Sunrise over the Philippine Sea

NASA Image and Video Library

1984-08-30

41D-32-14 (30 Aug 1984) --- A rainbow-like sunrise over the Philippine Sea greeted the six crew members aboard the Earth-orbiting Space Shuttle Discovery on its first day in space. A 70mm camera was used to record the scene at 3:08:14 p.m. (CDT), August 30, 1984, during Discovery's sixth orbit of a six-day mission. The spacecraft was above a position on Earth centered at 21.1 degrees north and 12.9 degrees east (about 250 miles north - northeast of the Philippine Islands). The scene was shown as one of the Post-Flight Press Conference (PFPC) visuals by the crew on September 12, 1984.

Sparse polynomial space approach to dissipative quantum systems: application to the sub-ohmic spin-boson model.

PubMed

Alvermann, A; Fehske, H

2009-04-17

We propose a general numerical approach to open quantum systems with a coupling to bath degrees of freedom. The technique combines the methodology of polynomial expansions of spectral functions with the sparse grid concept from interpolation theory. Thereby we construct a Hilbert space of moderate dimension to represent the bath degrees of freedom, which allows us to perform highly accurate and efficient calculations of static, spectral, and dynamic quantities using standard exact diagonalization algorithms. The strength of the approach is demonstrated for the phase transition, critical behavior, and dissipative spin dynamics in the spin-boson model.

An axisymmetric analog two-layer convective heating procedure with application to the evaluation of Space Shuttle Orbiter wing leading edge and windward surface heating

NASA Technical Reports Server (NTRS)

Wang, K. C.

1994-01-01

A numerical procedure for predicting the convective heating rate of hypersonic reentry vehicles is described. The procedure, which is based on the axisymmetric analog, consists of obtaining the three-dimensional inviscid flowfield solution; then the surface streamlines and metrics are calculated using the inviscid velocity components on the surface; finally, an axisymmetric boundary layer code or approximate convective heating equations are used to evaluate heating rates. This approach yields heating predictions to general three-dimensional body shapes. The procedure has been applied to the prediction of the wing leading edge heating to the Space Shuttle Orbiter. The numerical results are compared with the results of heat transfer testing (OH66) of an 0.025 scale model of the Space Shuttle Orbiter configuration in the Calspan Hypersonic Shock Tunnel (HST) at Mach 10 and angles of attack of 30 and 40 degrees. Comparisons with STS-5 flight data at Mach 9.15 and angle of attack of 37.4 degrees and STS-2 flight data at Mach 12.86 and angle of attack of 39.7 degrees are also given.

Applying the system engineering approach to devise a master’s degree program in space technology in developing countries

NASA Astrophysics Data System (ADS)

Jazebizadeh, Hooman; Tabeshian, Maryam; Taheran Vernoosfaderani, Mahsa

2010-11-01

Although more than half a century is passed since space technology was first developed, developing countries are just beginning to enter the arena, focusing mainly on educating professionals. Space technology by itself is an interdisciplinary science, is costly, and developing at a fast pace. Moreover, a fruitful education system needs to remain dynamic if the quality of education is the main concern, making it a complicated system. This paper makes use of the System Engineering Approach and the experiences of developed countries in this area while incorporating the needs of the developing countries to devise a comprehensive program in space engineering at the Master's level. The needs of the developing countries as regards space technology education may broadly be put into two categories: to raise their knowledge of space technology which requires hard work and teamwork skills, and to transfer and domesticate space technology while minimizing the costs and maximizing its effectiveness. The requirements of such space education system, which include research facilities, courses, and student projects are then defined using a model drawn from the space education systems in universities in North America and Europe that has been modified to include the above-mentioned needs. Three design concepts have been considered and synthesized through functional analysis. The first one is Modular and Detail Study which helps students specialize in a particular area in space technology. Second is referred to as Integrated and Interdisciplinary Study which focuses on understanding and development of space systems. Finally, the third concept which has been chosen for the purpose of this study, is a combination of the other two, categorizing the required curriculum into seven modules, setting aside space applications. This helps students to not only specialize in one of these modules but also to get hands-on experience in a real space project through participation in summer group projects and also working in space systems laboratories or choose and write a thesis based on experiences gained through an internship program.

Understanding the Decision to Enroll in Graduate School: Sex and Racial/Ethnic Group Differences

ERIC Educational Resources Information Center

Perna, Laura W.

2004-01-01

Women continue to receive fewer doctoral and first-professional degrees than men, even though women receive more bachelor's degrees. The underrepresentation of women holds even after allowing for time to complete an advanced degree. Although researchers have examined sex and racial/ethnic group differences in undergraduate enrollment (e.g.,…

The use of rice hulls for sustainable control of NOx emissions in deep space missions

NASA Technical Reports Server (NTRS)

Xu, X. H.; Shi, Y.; Kwak, D.; Chang, S. G.; Fisher, J. W.; Pisharody, S.; Moran, M. J.; Wignarajah, K.

2003-01-01

The use of the activated carbon produced from rice hulls to control NOx emissions for future deep space missions has been demonstrated. The optimal carbonization temperature range was found to be between 600 and 750 degrees C. A burnoff of 61.8% was found at 700 degrees C in pyrolysis and 750 degrees C in activation. The BET surface area of the activated carbon from rice hulls was determined to be 172 m2/g when prepared at 700 degrees C. The presence of oxygen in flue gas is essential for effective adsorption of NO by activated carbon. On the contrary, water vapor inhibits the adsorption efficiency of NO. Consequently, water vapor in flue gas should be removed by drying agents before adsorption to ensure high NO adsorption efficiency. All of the NO in the flue gas was removed for more than 1.5 h when 10% oxygen was present and the ratio of the carbon weight to the flue gas flow rate (W/F) was 15.4 g min/L. Reduction of the adsorbed NO to form N2 could be effectively accomplished under anaerobic conditions at 550 degrees C. The adsorption capacity of NO on the activated carbon was found to be 5.02 mg of NO/g of carbon. The loss of carbon mass was determined to be about 0.16% of the activated carbon per cycle of regeneration if the regeneration occurred when the NO in the flue gas after the carbon bed reached 4.8 ppm, the space maximum allowable concentration. The reduction of the adsorbed NO also regenerated the activated carbon, and the regenerated activated carbon exhibited an improved NO adsorption efficiency.

Low degree Earth's gravity coefficients determined from different space geodetic observations and climate models

NASA Astrophysics Data System (ADS)

Wińska, Małgorzata; Nastula, Jolanta

2017-04-01

Large scale mass redistribution and its transport within the Earth system causes changes in the Earth's rotation in space, gravity field and Earth's ellipsoid shape. These changes are observed in the ΔC21, ΔS21, and ΔC20 spherical harmonics gravity coefficients, which are proportional to the mass load-induced Earth rotational excitations. In this study, linear trend, decadal, inter-annual, and seasonal variations of low degree spherical harmonics coefficients of Earth's gravity field, determined from different space geodetic techniques, Gravity Recovery and Climate Experiment (GRACE), satellite laser ranging (SLR), Global Navigation Satellite System (GNSS), Earth rotation, and climate models, are examined. In this way, the contribution of each measurement technique to interpreting the low degree surface mass density of the Earth is shown. Especially, we evaluate an usefulness of several climate models from the Coupled Model Intercomparison Project phase 5 (CMIP5) to determine the low degree Earth's gravity coefficients using GRACE satellite observations. To do that, Terrestrial Water Storage (TWS) changes from several CMIP5 climate models are determined and then these simulated data are compared with the GRACE observations. Spherical harmonics ΔC21, ΔS21, and ΔC20 changes are calculated as the sum of atmosphere and ocean mass effect (GAC values) taken from GRACE and a land surface hydrological estimate from the selected CMIP5 climate models. Low degree Stokes coefficients of the surface mass density determined from GRACE, SLR, GNSS, Earth rotation measurements and climate models are compared to each other in order to assess their consistency. The comparison is done by using different types of statistical and signal processing methods.

Phase-locked laser array having a non-uniform spacing between lasing regions

NASA Technical Reports Server (NTRS)

Ackley, Donald E. (Inventor)

1986-01-01

A phase-locked semiconductor array wherein the lasing regions of the array are spaced an effective distance apart such that the modes of oscillation of the different lasing regions are phase-locked to one another. The center-to-center spacing between the lasing regions is non-uniform. This variation in spacing perturbs the preferred 180.degree. phase difference between adjacent lasing regions thereby providing an increased yield of arrays exhibiting a single-lobed, far-field radiation pattern.