semi-major axis change: Topics by Science.gov

Sample records for semi-major axis change

Semi-Major Axis Knowledge and GPS Orbit Determination

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Schiesser, Emil R.; Bauer, F. (Technical Monitor)

2000-01-01

In recent years spacecraft designers have increasingly sought to use onboard Global Positioning System receivers for orbit determination. The superb positioning accuracy of GPS has tended to focus more attention on the system's capability to determine the spacecraft's location at a particular epoch than on accurate orbit determination, per se. The determination of orbit plane orientation and orbit shape to acceptable levels is less challenging than the determination of orbital period or semi-major axis. It is necessary to address semi-major axis mission requirements and the GPS receiver capability for orbital maneuver targeting and other operations that require trajectory prediction. Failure to determine semi-major axis accurately can result in a solution that may not be usable for targeting the execution of orbit adjustment and rendezvous maneuvers. Simple formulas, charts, and rules of thumb relating position, velocity, and semi-major axis are useful in design and analysis of GPS receivers for near circular orbit operations, including rendezvous and formation flying missions. Space Shuttle flights of a number of different GPS receivers, including a mix of unfiltered and filtered solution data and Standard and Precise Positioning Service modes, have been accomplished. These results indicate that semi-major axis is often not determined very accurately, due to a poor velocity solution and a lack of proper filtering to provide good radial and speed error correlation.
Semi-Major Axis Knowledge and GPS Orbit Determination

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Schiesser, Emil R.; Bauer, F. (Technical Monitor)

2000-01-01

In recent years spacecraft designers have increasingly sought to use onboard Global Positioning System receivers for orbit determination. The superb positioning accuracy of GPS has tended to focus more attention on the system's capability to determine the spacecraft's location at a particular epoch than on accurate orbit determination, per se. The determination of orbit plane orientation and orbit shape to acceptable levels is less challenging than the determination of orbital period or semi-major axis. It is necessary to address semi-major axis mission requirements and the GPS receiver capability for orbital maneuver targeting and other operations that require trajectory prediction. Failure to determine semi-major axis accurately can result in a solution that may not be usable for targeting the execution of orbit adjustment and rendezvous maneuvers. Simple formulas, charts, and rules of thumb relating position, velocity, and semi-major axis are useful in design and analysis of GPS receivers for near circular orbit operations, including rendezvous and formation flying missions. Space Shuttle flights of a number of different GPS receivers, including a mix of unfiltered and filtered solution data and Standard and Precise Positioning, Service modes, have been accomplished. These results indicate that semi-major axis is often not determined very accurately, due to a poor velocity solution and a lack of proper filtering to provide good radial and speed error correlation.
The Importance of Semi-Major Axis Knowledge in the Determination of Near-Circular Orbits

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Schiesser, Emil R.

1998-01-01

Modem orbit determination has mostly been accomplished using Cartesian coordinates. This usage has carried over in recent years to the use of GPS for satellite orbit determination. The unprecedented positioning accuracy of GPS has tended to focus attention more on the system's capability to locate the spacecraft's location at a particular epoch than on its accuracy in determination of the orbit, per se. As is well-known, the latter depends on a coordinated knowledge of position, velocity, and the correlation between their errors. Failure to determine a properly coordinated position/velocity state vector at a given epoch can lead to an epoch state that does not propagate well, and/or may not be usable for the execution of orbit adjustment maneuvers. For the quite common case of near-circular orbits, the degree to which position and velocity estimates are properly coordinated is largely captured by the error in semi-major axis (SMA) they jointly produce. Figure 1 depicts the relationships among radius error, speed error, and their correlation which exist for a typical low altitude Earth orbit. Two familiar consequences are the relationship Figure 1 shows are the following: (1) downrange position error grows at the per orbit rate of 3(pi) times the SMA error; (2) a velocity change imparted to the orbit will have an error of (pi) divided by the orbit period times the SMA error. A less familiar consequence occurs in the problem of initializing the covariance matrix for a sequential orbit determination filter. An initial covariance consistent with orbital dynamics should be used if the covariance is to propagate well. Properly accounting for the SMA error of the initial state in the construction of the initial covariance accomplishes half of this objective, by specifying the partition of the covariance corresponding to down-track position and radial velocity errors. The remainder of the in-plane covariance partition may be specified in terms of the flight path angle
Process and apparatus for measuring degree of polarization and angle of major axis of polarized beam of light

DOEpatents

Decker, Derek E.; Toeppen, John S.

1994-01-01

Apparatus and process are disclosed for calibrating measurements of the phase of the polarization of a polarized beam and the angle of the polarized optical beam's major axis of polarization at a diagnostic point with measurements of the same parameters at a point of interest along the polarized beam path prior to the diagnostic point. The process is carried out by measuring the phase angle of the polarization of the beam and angle of the major axis at the point of interest, using a rotatable polarizer and a detector, and then measuring these parameters again at a diagnostic point where a compensation apparatus, including a partial polarizer, which may comprise a stack of glass plates, is disposed normal to the beam path between a rotatable polarizer and a detector. The partial polarizer is then rotated both normal to the beam path and around the axis of the beam path until the detected phase of the beam polarization equals the phase measured at the point of interest. The rotatable polarizer at the diagnostic point may then be rotated manually to determine the angle of the major axis of the beam and this is compared with the measured angle of the major axis of the beam at the point of interest during calibration. Thereafter, changes in the polarization phase, and in the angle of the major axis, at the point of interest can be monitored by measuring the changes in these same parameters at the diagnostic point.
Nonlinear dual-axis biodynamic response of the semi-supine human body during vertical whole-body vibration

NASA Astrophysics Data System (ADS)

Huang, Ya; Griffin, Michael J.

2008-04-01

Nonlinear biodynamic responses are evident in many studies of the apparent masses of sitting and standing subjects in static postures that require muscle activity for postural control. In the present study, 12 male subjects adopted a relaxed semi-supine posture assumed to involve less muscle activity than during static sitting and standing. The supine subjects were exposed to two types of vertical vibration (in the x-axis of the semi-supine body): (i) continuous random vibration (0.25-20 Hz) at five magnitudes (0.125, 0.25, 0.5, 0.75, and 1.0 m s -2 rms); (ii) intermittent random vibration (0.25-20 Hz) alternately at 0.25 and 1.0 m s -2 rms. With continuous random vibration, the dominant primary resonance frequency in the median normalised apparent mass decreased from 10.35 to 7.32 Hz as the vibration magnitude increased from 0.125 to 1.0 m s -2 rms. This nonlinear response was apparent in both the vertical ( x-axis) apparent mass and in the horizontal ( z-axis) cross-axis apparent mass. As the vibration magnitude increased from 0.25 to 1.0 m s -2 rms, the median resonance frequency of the apparent mass with intermittent random vibration decreased from 9.28 to 8.06 Hz whereas, over the same range of magnitudes with continuous random vibration, the resonance frequency decreased from 9.62 to 7.81 Hz. The median change in the resonance frequency (between 0.25 and 1.0 m s -2 rms) was 1.37 Hz with the intermittent random vibration and 1.71 with the continuous random vibration. With the intermittent vibration, the resonance frequency was higher at the high magnitude and lower at the low magnitude than with continuous vibration of the same magnitudes. The response was typical of thixotropy that may be a primary cause of the nonlinear biodynamic responses to whole-body vibration.
Nonlinear dual-axis biodynamic response of the semi-supine human body during longitudinal horizontal whole-body vibration

NASA Astrophysics Data System (ADS)

Huang, Ya; Griffin, Michael J.

2008-04-01

The resonance frequencies in frequency response functions of the human body (e.g. apparent mass and transmissibility) decrease with increasing vibration magnitude. This nonlinear biodynamic response is found with various sitting and standing postures requiring postural control. The present study measured the apparent mass of the body in a relaxed semi-supine posture with two types of longitudinal horizontal vibration (in the z-axis of the semi-supine body): (i) continuous random excitation (0.25-20 Hz) at five magnitudes (0.125, 0.25, 0.5, 0.75 and 1.0 ms -2 rms); (ii) intermittent random excitation (0.25-20 Hz) alternately at 0.25 and 1.0 ms -2 rms. With continuous random vibration, the dominant primary resonance frequency in the median normalised apparent mass decreased from 3.7 to 2.4 Hz as the vibration magnitude increased from 0.125 to 1.0 ms -2 rms. A nonlinear response was apparent in both the horizontal ( z-axis) apparent mass and the vertical ( x-axis) cross-axis apparent mass. With intermittent random vibration, as the vibration magnitude increased from 0.25 to 1.0 ms -2 rms, the median resonance frequency of the apparent mass decreased from 3.2 to 2.5 Hz whereas, with continuous random vibration over the same range of magnitudes, the resonance frequency decreased from 3.4 to 2.4 Hz. The median change in the resonance frequency (between 0.25 and 1.0 ms -2 rms) was 0.6 Hz with the intermittent random vibration and 0.9 Hz with the continuous random vibration. With intermittent vibration, the resonance frequency was higher at the high magnitude and lower at the low magnitude than with continuous vibration at the same magnitudes. The responses were consistent with passive thixotropy being a primary cause of nonlinear biodynamic responses to whole-body vibration, although reflex activity of the muscles may also have an influence.
Acute myocardial infarction with changing axis deviation.

PubMed

Patanè, Salvatore; Marte, Filippo

2011-07-01

Changing axis deviation has been rarely reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been rarely reported also during acute myocardial infarction associated with atrial fibrillation. Isolated left posterior hemiblock is a very rare finding but the evidence of transient right axis deviation with a left posterior hemiblock pattern has been reported during acute anterior myocardial infarction as related with significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery. Left anterior hemiblock development during acute inferior myocardial infarction can be an indicator of left anterior descending coronary artery lesions, multivessel coronary artery disease, and impaired left ventricular systolic function. We present a case of changing axis deviation in a 62-year-old Italian man with acute myocardial infarction. Also this case focuses attention on changing axis deviation during acute myocardial infarction. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Sequence-dependent rotation axis changes in tennis.

PubMed

Hansen, Clint; Martin, Caroline; Rezzoug, Nasser; Gorce, Philippe; Bideau, Benoit; Isableu, Brice

2017-09-01

The purpose of this study was to evaluate the role of rotation axes during a tennis serve. A motion capture system was used to evaluate the contribution of the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis) during the four discrete tennis serve phases (loading, cocking, acceleration and follow through). Ten ranked athletes (International Tennis Number 1-3) repeatedly performed a flat service aiming at a target on the other side of the net. The four serve phases are distinct and thus, each movement phase seems to be organised around specific rotation axes. The results showed that the limbs' rotational axis does not necessarily coincide with the minimum inertia axis across the cocking phase of the tennis serve. Even though individual serving strategies were exposed, all participants showed an effect due to the cocking phase and changed the rotation axis during the task. Taken together, the results showed that despite inter-individual differences, nine out of 10 participants changed the rotation axis towards the minimum inertia and/or the mass axis in an endeavour to maximise external rotation of the shoulder to optimally prepare for the acceleration phase.
Changing axis deviation during acute myocardial infarction.

PubMed

Patanè, Salvatore; Marte, Filippo

2010-07-09

Changing axis deviation has been reported during acute myocardial infarction also associated with atrial fibrillation. Isolated left posterior hemiblock is a very rare finding but the evidence of transient right axis deviation with a left posterior hemiblock pattern has been reported during acute anterior myocardial infarction as related with significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery. We present a case of changing axis deviation in a 70-year-old Italian man with acute myocardial infarction. Copyright (c) 2008 Elsevier Ireland Ltd. All rights reserved.
Fabrication of 4H-SiC lateral double implanted MOSFET on an on-axis semi-insulating substrate without using epi-layer

NASA Astrophysics Data System (ADS)

Kim, Hyoung Woo; Seok, Ogyun; Moon, Jeong Hyun; Bahng, Wook; Jo, Jungyol

2017-12-01

4H-SiC lateral double implanted metal-oxide-semiconductor field effect transistors (LDIMOSFET) were fabricated on on-axis semi-insulating SiC substrates without using an epi-layer. The LDIMOSFET adopted a current path layer (CPL), which was formed by ion-implantation. The CPL works as a drift region between gate and drain. By using on-axis semi-insulating substrate and optimized CPL parameters, breakdown voltage (BV) of 1093 V and specific on-resistance (R on,sp) of 89.8 mΩ·cm2 were obtained in devices with 20 µm long CPL. Experimentally extracted field-effect channel mobility was 21.7 cm2·V-1·s-1 and the figure-of-merit (BV2/R on,sp) was 13.3 MW/cm2.
Multipole plasmons in graphene nanoellipses

NASA Astrophysics Data System (ADS)

Wang, Weihua; Song, Zhengyong

2018-02-01

We study multipole plasmons in graphene nanoellipses under the quasi-static approximation. The graphene is characterized by a homogeneous surface conductivity, and two coupled differential and integral equations are solved self-consistently to investigate the plasmonic modes in nanoellipses with a fixed area. With respect to the major axis, the symmetric and antisymmetric modes originally doubly degenerate in nanodisks will show different behavior as the semi-major axis increases. The eigen frequencies of the symmetric modes decrease, while those of the antisymmetric modes increase. At the edges, the phase changes of the symmetric dipole modes are linear and independent on structural changes; the phase changes of antisymmetric modes deviate from linear relationship, and the deviation depends on the semi-major axis. As a very large aspect ratio, they exhibit sharp peaks at the endpoints of the minor axis and zero phase changes at the endpoints of the major axis. The non-degenerate breathing mode shows its hot spots at the endpoints of the minor axis, and its eigen frequency gradually increases as the semi-major axis increases.
Averaged changes in the orbital elements of meteoroids due to Yarkovsky-Radzievskij force

NASA Astrophysics Data System (ADS)

Ryabova, Galina O.

2014-07-01

Yarkovsky-Radzievskij effect exceeds the Poynting-Robertson effect in the perturbing action on particles larger than 100 μm. We obtained formulae for averaged changes in a meteoroid's Keplerian orbital elements and used them to estimate dispersion in the Geminid meteoroid stream. It was found that dispersion in semi-major axis of the model shower increased nearly three times on condition that meteoroids rotation is fast, and the rotation axis is stable.
Sequence-dependent rotation axis changes and interaction torque use in overarm throwing.

PubMed

Hansen, Clint; Rezzoug, Nasser; Gorce, Philippe; Venture, Gentiane; Isableu, Brice

2016-01-01

We examined the role of rotation axes during an overarm throwing task. Participants performed such task and were asked to throw a ball at maximal velocity at a target. The purpose of this study was to examine whether the minimum inertia axis would be exploited during the throwing phases, a time when internal-external rotations of the shoulder are particularly important. A motion capture system was used to evaluate the performance and to compute the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis). More specifically, we investigated whether a velocity-dependent change in rotational axes can be observed in the different throwing phases and whether the control obeys the principle of minimum inertia resistance. Our results showed that the limbs' rotational axis mainly coincides with the minimum inertia axis during the cocking phase and with the shoulder-elbow axis during the acceleration phase. Besides these rotation axes changes, the use of interaction torque is also sequence-dependent. The sequence-dependent rotation axes changes associated with the use of interaction torque during the acceleration phase could be a key factor in the production of hand velocity at ball release.
HPA-Axis Hormone Modulation of Stress Response Circuitry Activity in Women with Remitted Major Depression

PubMed Central

Holsen, Laura M.; Lancaster, Katie; Klibanski, Anne; Whitfield-Gabrieli, Susan; Cherkerzian, Sara; Buka, Stephen; Goldstein, Jill M.

2013-01-01

Decades of clinical and basic research indicate significant links between altered hypothalamic-pituitary-adrenal (HPA)-axis hormone dynamics and major depressive disorder (MDD). Recent neuroimaging studies of MDD highlight abnormalities in stress response circuitry regions which play a role in the regulation of the HPA-axes. However, there is a dearth of research examining these systems in parallel, especially as related to potential trait characteristics. The current study addresses this gap by investigating neural responses to a mild visual stress challenge with real-time assessment of adrenal hormones in women with MDD in remission and controls. 15 women with recurrent MDD in remission (rMDD) and 15 healthy control women were scanned on a 3T Siemens MR scanner while viewing neutral and negative (stress-evoking) stimuli. Blood samples were obtained before, during, and after scanning for measurement of HPA-axis hormone levels. Compared to controls, rMDD women demonstrated higher anxiety ratings, increased cortisol levels, and hyperactivation in the amygdala and hippocampus, p<0.05, FWE-corrected in response to the stress challenge. Among rMDD women, amygdala activation was negatively related to cortisol changes and positively associated with duration of remission. Findings presented here provide evidence for differential effects of altered HPA-axis hormone dynamics on hyperactivity in stress response circuitry regions elicited by a well-validated stress paradigm in women with recurrent MDD in remission. PMID:23891965
Semi-continuous mass closure of the major components of fine particulate matter in Riverside, CA

NASA Astrophysics Data System (ADS)

Grover, Brett D.; Eatough, Norman L.; Woolwine, Woods R.; Cannon, Justin P.; Eatough, Delbert J.; Long, Russell W.

The application of newly developed semi-continuous aerosol monitors allows for the measurement of all the major species of PM 2.5 on a 1-h time basis. Temporal resolution of both non-volatile and semi-volatile species is possible. A suite of instruments to measure the major chemical species of PM 2.5 allows for semi-continuous mass closure. A newly developed dual-oven Sunset carbon monitor is used to measure non-volatile organic carbon, semi-volatile organic carbon and elemental carbon. Inorganic species, including sulfate and nitrate, can be measured with an ion chromatograph based sampler. Comparison of the sum of the major chemical species in an urban aerosol with mass measured by an FDMS resulted in excellent agreement. Linear regression analysis resulted in a zero-intercept slope of 0.98±0.01 with an R2=0.86. One-hour temporal resolution of the major species of PM 2.5 may reduce the uncertainty in receptor based source apportionment modeling, will allow for better forecasting of PM 2.5 episodes, and may lead to increased understanding of related health effects.
Revelation of changing axis deviation at the end of atrial fibrillation during acute myocardial infarction.

PubMed

Patanè, Salvatore; Marte, Filippo

2011-05-19

It has been rarely reported changing axis deviation also during atrial fibrillation or atrial flutter. Changing axis deviation has been also rarely reported during acute myocardial infarction associated with atrial fibrillation too. We present a case of a 49-year-old Italian man with revelation of changing axis deviation at the end of atrial fibrillation during acute myocardial infarction. Also this case focuses attention on changing axis deviation. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Coping with changing northern environments: the role of the stress axis in birds and mammals.

PubMed

Boonstra, Rudy

2004-04-01

Northern environments present ecological and physiological problems for homeotherms that require adaptations to cope with severe and less predictable physical factors while at the same time continuing to have to cope with the biological ones, such as competition and predation. The stress axis plays a central role in these adaptations and I discuss the range of solutions that birds and mammals have evolved. The stress response in these animals is not static when a challenge occurs, but may be modulated depending on the biological function during the annual cycle (breeding versus nonbreeding), either under-responding to permit reproduction (some song birds) or responding vigorously, yet not having this compromise reproduction (Arctic ground squirrels). Both may trade off survival for reproduction. In contrast, the snowshoe hare shows the expected stress response to chronic high predation risk over 2-3 years: body resources are geared to survival and reproduction is inhibited. Two long term, persistent, and pervasive changes will confront northern birds and mammals in the 21(st) century: global change and persistent organochlorine pollutants (POPs). These may result in either adaptations or shifts in distribution and abundance. For the former, latitudinal variation in the stress axis may help song birds respond rapidly; population variation in the stress axis response is unknown in northern mammals and relatively sedentary mammals may be unable to shift their distribution rapidly to adjust major climate shifts. For the latter, the few POPs studies that have examined the stress axis indicate marked negative effects.
Psychosocial stressors and the prognosis of major depression: a test of Axis IV

PubMed Central

Gilman, Stephen E.; Trinh, Nhi-Ha; Smoller, Jordan W.; Fava, Maurizio; Murphy, Jane M.; Breslau, Joshua

2013-01-01

Background Axis IV is for reporting “psychosocial and environmental problems that may affect the diagnosis, treatment, and prognosis of mental disorders.” No studies have examined the prognostic value of Axis IV in DSM-IV. Method We analyzed data from 2,497 participants in the National Epidemiologic Survey on Alcohol and Related Conditions with major depressive episode (MDE). We hypothesized that psychosocial stressors predict a poor prognosis of MDE. Secondarily, we hypothesized that psychosocial stressors predict a poor prognosis of anxiety and substance use disorders. Stressors were defined according to DSM-IV’s taxonomy, and empirically using latent class analysis. Results Primary support group problems, occupational problems, and childhood adversity increased the risks of depressive episodes and suicidal ideation by 20–30%. Associations of the empirically derived classes of stressors with depression were larger in magnitude. Economic stressors conferred a 1.5-fold increase in risk for a depressive episode (CI=1.2–1.9); financial and interpersonal instability conferred a 1.3-fold increased risk of recurrent depression (CI=1.1–1.6). These two classes of stressors also predicted the recurrence of anxiety and substance use disorders. Stressors were not related to suicidal ideation independent from depression severity. Conclusions Psychosocial and environmental problems are associated with the prognosis of MDE and other Axis I disorders. Though DSM-IV’s taxonomy of stressors stands to be improved, these results provide empirical support for the prognostic value of Axis IV. Future work is needed to determine the reliability of Axis IV assessments in clinical practice, and the usefulness of this information to improving the clinical course of mental disorders. PMID:22640506
Gravin regulates mesodermal cell behavior changes required for axis elongation during zebrafish gastrulation.

PubMed

Weiser, Douglas C; Pyati, Ujwal J; Kimelman, David

2007-06-15

Convergent extension of the mesoderm is the major driving force of vertebrate gastrulation. During this process, mesodermal cells move toward the future dorsal side of the embryo, then radically change behavior as they initiate extension of the body axis. How cells make this transition in behavior is unknown. We have identified the scaffolding protein and tumor suppressor Gravin as a key regulator of this process in zebrafish embryos. We show that Gravin is required for the conversion of mesodermal cells from a highly migratory behavior to the medio-laterally intercalative behavior required for body axis extension. In the absence of Gravin, paraxial mesodermal cells fail to shut down the protrusive activity mediated by the Rho/ROCK/Myosin II pathway, resulting in embryos with severe extension defects. We propose that Gravin functions as an essential scaffold for regulatory proteins that suppress the migratory behavior of the mesoderm during gastrulation, and suggest that this function also explains how Gravin inhibits invasive behaviors in metastatic cells.
The association between the hypothalamic pituitary adrenal axis and tryptophan metabolism in persons with recurrent major depressive disorder and healthy controls.

PubMed

Sorgdrager, F J H; Doornbos, B; Penninx, B W J H; de Jonge, P; Kema, I P

2017-11-01

Persistent changes in serotonergic and hypothalamic pituitary adrenal (HPA) axis functioning are implicated in recurrent types of major depressive disorder (MDD). Systemic tryptophan levels, which influence the rate of serotonin synthesis, are regulated by glucocorticoids produced along the HPA axis. We investigated tryptophan metabolism and its association with HPA axis functioning in single episode MDD, recurrent MDD and non-depressed individuals. We included depressed individuals (n = 1320) and controls (n = 406) from the Netherlands Study of Depression and Anxiety (NESDA). The kynurenine to tryptophan ratio (kyn/trp ratio) was established using serum kynurenine and tryptophan levels. Several HPA axis parameters were calculated using salivary cortisol samples. We adjusted the regression analyses for a wide range of potential confounders and differentiated between single episode MDD, recurrent MDD and control. Tryptophan, kynurenine and the kyn/trp ratio did not differ between controls and depressed individuals. Increased evening cortisol levels were associated with a decreased kyn/trp ratio in the total sample (Crude: β = -.102, p < .001; Adjusted: β = -.083, p < .001). This association was found to be restricted to recurrently depressed individuals (Crude: β = -.196, p < .001; Adjusted: β = -.145, p = .001). Antidepressant treatment did not affect this association. Our results suggest that an imbalance between HPA axis function and tryptophan metabolism could be involved in recurrent depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Improvement of the insertion axis for cochlear implantation with a robot-based system.

PubMed

Torres, Renato; Kazmitcheff, Guillaume; De Seta, Daniele; Ferrary, Evelyne; Sterkers, Olivier; Nguyen, Yann

2017-02-01

It has previously reported that alignment of the insertion axis along the basal turn of the cochlea was depending on surgeon' experience. In this experimental study, we assessed technological assistances, such as navigation or a robot-based system, to improve the insertion axis during cochlear implantation. A preoperative cone beam CT and a mastoidectomy with a posterior tympanotomy were performed on four temporal bones. The optimal insertion axis was defined as the closest axis to the scala tympani centerline avoiding the facial nerve. A neuronavigation system, a robot assistance prototype, and software allowing a semi-automated alignment of the robot were used to align an insertion tool with an optimal insertion axis. Four procedures were performed and repeated three times in each temporal bone: manual, manual navigation-assisted, robot-based navigation-assisted, and robot-based semi-automated. The angle between the optimal and the insertion tool axis was measured in the four procedures. The error was 8.3° ± 2.82° for the manual procedure (n = 24), 8.6° ± 2.83° for the manual navigation-assisted procedure (n = 24), 5.4° ± 3.91° for the robot-based navigation-assisted procedure (n = 24), and 3.4° ± 1.56° for the robot-based semi-automated procedure (n = 12). A higher accuracy was observed with the semi-automated robot-based technique than manual and manual navigation-assisted (p < 0.01). Combination of a navigation system and a manual insertion does not improve the alignment accuracy due to the lack of friendly user interface. On the contrary, a semi-automated robot-based system reduces both the error and the variability of the alignment with a defined optimal axis.
Multilocus phylogeny, divergence times, and a major role for the benthic-to-pelagic axis in the diversification of grunts (Haemulidae).

PubMed

Tavera, Jose; Acero P, Arturo; Wainwright, Peter C

2018-04-01

We present a phylogenetic analysis with divergence time estimates, and an ecomorphological assessment of the role of the benthic-to-pelagic axis of diversification in the history of haemulid fishes. Phylogenetic analyses were performed on 97 grunt species based on sequence data collected from seven loci. Divergence time estimation indicates that Haemulidae originated during the mid Eocene (54.7-42.3 Ma) but that the major lineages were formed during the mid-Oligocene 30-25 Ma. We propose a new classification that reflects the phylogenetic history of grunts. Overall the pattern of morphological and functional diversification in grunts appears to be strongly linked with feeding ecology. Feeding traits and the first principal component of body shape strongly separate species that feed in benthic and pelagic habitats. The benthic-to-pelagic axis has been the major axis of ecomorphological diversification in this important group of tropical shoreline fishes, with about 13 transitions between feeding habitats that have had major consequences for head and body morphology. Copyright © 2017 Elsevier Inc. All rights reserved.
Stress and serial adult metamorphosis: multiple roles for the stress axis in socially regulated sex change.

PubMed

Solomon-Lane, Tessa K; Crespi, Erica J; Grober, Matthew S

2013-01-01

Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds) has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis). Through actions of both corticotropin-releasing factor and glucocorticoids, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli), a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes.
Stress and serial adult metamorphosis: multiple roles for the stress axis in socially regulated sex change

PubMed Central

Solomon-Lane, Tessa K.; Crespi, Erica J.; Grober, Matthew S.

2013-01-01

Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds) has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis). Through actions of both corticotropin-releasing factor and glucocorticoids, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli), a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes. PMID:24265604
Major off-axis hydrothermal activity on the northern Gorda Ridge

USGS Publications Warehouse

Rona, Peter A.; Denlinger, Roger P.; Fisk, M. R.; Howard, K. J.; Taghon, G. L.; Klitgord, Kim D.; McClain, James S.; McMurray, G. R.; Wiltshire, J. C.

1990-01-01

The first hydrothermal field on the northern Gorda Ridge, the Sea Cliff hydrothermal field, was discovered and geologic controls of hydrothermal activity in the rift valley were investigated on a dive series using the DSV Sea Cliff. The Sea Cliff hydrothermal field was discovered where predicted at the intersection of axis-oblique and axis-parallel faults at the south end of a linear ridge at mid-depth (2700 m) on the east wall. Preliminary mapping and sampling of the field reveal: a setting nested on nearly sediment-free fault blocks 300 m above the rift valley floor 2.6 km from the axis; a spectrum of venting types from seeps to black smokers; high conductive heat flow estimated to be equivalent to the convective flux of multiple black smokers through areas of the sea floor sealed by a caprock of elastic breccia primarily derived from basalt with siliceous cement and barite pore fillings; and a vent biota with Juan de Fuca Ridge affinites. These findings demonstrate the importance of off-axis hydrothermal activity and the role of the intersection of tectonic lineations in controlling hydrothermal sites at sea-floor spreading centers.
Quaternary ecological and geomorphic changes associated with rainfall events in presently semi-arid northeastern Brazil

NASA Astrophysics Data System (ADS)

Auler, Augusto S.; Wang, Xianfeng; Edwards, R. Lawrence; Cheng, Hai; Cristalli, Patrícia S.; Smart, Peter L.; Richards, David A.

2004-10-01

Several geomorphic features and palaeobiotic remains in now semi-arid northeastern Brazil indicate major palaeoenvironmental changes during past periods of increased rainfall. 230Th mass spectrometric ages of speleothems and travertines have allowed the determination of the timing and duration of wetter than present conditions. The data demonstrate that wet events have occurred throughout much of the Pleistocene, present dry conditions having been established at the end of the Younger Dryas. A markedly different fauna comprising megafaunal elements not adapted to the present low arboreal scrubland caatinga vegetation existed in the area. Palaeobotanical remains embedded in travertine indicate forested vegetation at these wetter intervals, suggesting that the caatinga was then replaced or mixed with a semi-deciduous forest. Due to the abundance of travertine sites containing fossil botanical remains in northeastern Brazil, it is believed that forest expansion occurred over large areas of the now semi-arid zone, showing that the long hypothesised forested links between biodiversity-rich Amazon and Atlantic rainforests may indeed have existed during these moister phases. Copyright
Intermittent changing axis deviation with intermittent left anterior hemiblock during atrial flutter with subclinical hyperthyroidism.

PubMed

Patanè, Salvatore; Marte, Filippo

2009-06-26

Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. It has been reported that subclinical hyperthyroidism is not associated with CHD or mortality from cardiovascular causes but it is usually associated with a higher heart rate and a higher risk of supraventricular arrhythmias including atrial fibrillation and atrial flutter. Intermittent changing axis deviation during atrial fibrillation has also rarely been reported. We present a case of intermittent changing axis deviation with intermittent left anterior hemiblock in a 59-year-old Italian man with atrial flutter and subclinical hyperthyroidism. To our knowledge, this is the first report of intermittent changing axis deviation with intermittent left anterior hemiblock in a patient with atrial flutter.
Changing axis deviation and paroxysmal atrial flutter associated with subclinical hyperthyroidism.

PubMed

Patanè, Salvatore; Marte, Filippo

2010-10-08

Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. It has been reported that subclinical hyperthyroidism is not associated with coronary heart disease or mortality from cardiovascular causes but it is sufficient to induce arrhythmias including atrial fibrillation and atrial flutter. It has also been reported that increased factor X activity in patients with subclinical hyperthyroidism represents a potential hypercoagulable state. Rarely, it has also been reported intermittent changing axis deviation during atrial fibrillation and during atrial flutter. We present a case of paroxysmal atrial flutter and changing axis deviation associated with subclinical hyperthyroidism, in a 76-year-old Italian man. Also this case focuses attention on the importance of a correct evaluation of subclinical hyperthyroidism. Copyright © 2008 Elsevier Ireland Ltd. All rights reserved.
Semi-Metric Topology of the Human Connectome: Sensitivity and Specificity to Autism and Major Depressive Disorder.

PubMed

Simas, Tiago; Chattopadhyay, Shayanti; Hagan, Cindy; Kundu, Prantik; Patel, Ameera; Holt, Rosemary; Floris, Dorothea; Graham, Julia; Ooi, Cinly; Tait, Roger; Spencer, Michael; Baron-Cohen, Simon; Sahakian, Barbara; Bullmore, Ed; Goodyer, Ian; Suckling, John

2015-01-01

The human functional connectome is a graphical representation, consisting of nodes connected by edges, of the inter-relationships of blood oxygenation-level dependent (BOLD) time-series measured by MRI from regions encompassing the cerebral cortices and, often, the cerebellum. Semi-metric analysis of the weighted, undirected connectome distinguishes an edge as either direct (metric), such that there is no alternative path that is accumulatively stronger, or indirect (semi-metric), where one or more alternative paths exist that have greater strength than the direct edge. The sensitivity and specificity of this method of analysis is illustrated by two case-control analyses with independent, matched groups of adolescents with autism spectrum conditions (ASC) and major depressive disorder (MDD). Significance differences in the global percentage of semi-metric edges was observed in both groups, with increases in ASC and decreases in MDD relative to controls. Furthermore, MDD was associated with regional differences in left frontal and temporal lobes, the right limbic system and cerebellum. In contrast, ASC had a broadly increased percentage of semi-metric edges with a more generalised distribution of effects and some areas of reduction. In summary, MDD was characterised by localised, large reductions in the percentage of semi-metric edges, whilst ASC is characterised by more generalised, subtle increases. These differences were corroborated in greater detail by inspection of the semi-metric backbone for each group; that is, the sub-graph of semi-metric edges present in >90% of participants, and by nodal degree differences in the semi-metric connectome. These encouraging results, in what we believe is the first application of semi-metric analysis to neuroimaging data, raise confidence in the methodology as potentially capable of detection and characterisation of a range of neurodevelopmental and psychiatric disorders.
Semi-Metric Topology of the Human Connectome: Sensitivity and Specificity to Autism and Major Depressive Disorder

PubMed Central

Simas, Tiago; Chattopadhyay, Shayanti; Hagan, Cindy; Kundu, Prantik; Patel, Ameera; Holt, Rosemary; Floris, Dorothea; Graham, Julia; Ooi, Cinly; Tait, Roger; Spencer, Michael; Baron-Cohen, Simon; Sahakian, Barbara; Bullmore, Ed; Goodyer, Ian; Suckling, John

2015-01-01

Introduction The human functional connectome is a graphical representation, consisting of nodes connected by edges, of the inter-relationships of blood oxygenation-level dependent (BOLD) time-series measured by MRI from regions encompassing the cerebral cortices and, often, the cerebellum. Semi-metric analysis of the weighted, undirected connectome distinguishes an edge as either direct (metric), such that there is no alternative path that is accumulatively stronger, or indirect (semi-metric), where one or more alternative paths exist that have greater strength than the direct edge. The sensitivity and specificity of this method of analysis is illustrated by two case-control analyses with independent, matched groups of adolescents with autism spectrum conditions (ASC) and major depressive disorder (MDD). Results Significance differences in the global percentage of semi-metric edges was observed in both groups, with increases in ASC and decreases in MDD relative to controls. Furthermore, MDD was associated with regional differences in left frontal and temporal lobes, the right limbic system and cerebellum. In contrast, ASC had a broadly increased percentage of semi-metric edges with a more generalised distribution of effects and some areas of reduction. In summary, MDD was characterised by localised, large reductions in the percentage of semi-metric edges, whilst ASC is characterised by more generalised, subtle increases. These differences were corroborated in greater detail by inspection of the semi-metric backbone for each group; that is, the sub-graph of semi-metric edges present in >90% of participants, and by nodal degree differences in the semi-metric connectome. Conclusion These encouraging results, in what we believe is the first application of semi-metric analysis to neuroimaging data, raise confidence in the methodology as potentially capable of detection and characterisation of a range of neurodevelopmental and psychiatric disorders. PMID:26308854
Relationships of neuroticism and extraversion with axis I and II comorbidity among patients with DSM-IV major depressive disorder.

PubMed

Jylhä, Pekka; Melartin, Tarja; Isometsä, Erkki

2009-04-01

High comorbidity with axis I and II disorders among major depressive disorder (MDD) patients may in part be due to the predisposing personality dimensions of neuroticism and extraversion. However, a comprehensive view of this relationship is lacking. MDD patients (n=193) in the Vantaa Depression Study were interviewed at baseline and at 6 and 18 months with the SCAN and SCID-II, and a general population comparison group (n=388) surveyed by mail. Neuroticism and extraversion were measured with the Eysenck Personality Inventory. A dose-exposure relationship between standardized levels of neuroticism and extraversion and type and number of comorbid axis I and II disorders among patients with MDD was hypothesized. Prevalence and number of comorbid axis I and II disorders increased significantly with increasing level of neuroticism. In contrast, as the level of extraversion increased, the prevalences of social phobia and cluster C personality disorders decreased. Patients with pure MDD or with any comorbid axis I or II disorder had z-scores of neuroticism of +0.46, +0.90 and +1.30 and of extraversion of -0.34, -0.47 and -0.84, respectively. Patients' personality scores were not pre-morbid. Among MDD patients, a positive dose-exposure relationship appears to exist between neuroticism and prevalence and number of comorbid axis I and II disorders. A negative relationship exists between level of extraversion and prevalence of social phobia and cluster C personality disorders. These findings are consistent with the hypothesis that high neuroticism and low extraversion predispose to comorbid axis I and II disorders among patients with MDD.
Pathwise upper semi-continuity of random pullback attractors along the time axis

NASA Astrophysics Data System (ADS)

Cui, Hongyong; Kloeden, Peter E.; Wu, Fuke

2018-07-01

The pullback attractor of a non-autonomous random dynamical system is a time-indexed family of random sets, typically having the form {At(ṡ) } t ∈ R with each At(ṡ) a random set. This paper is concerned with the nature of such time-dependence. It is shown that the upper semi-continuity of the mapping t ↦At(ω) for each ω fixed has an equivalence relationship with the uniform compactness of the local union ∪s∈IAs(ω) , where I ⊂ R is compact. Applied to a semi-linear degenerate parabolic equation with additive noise and a wave equation with multiplicative noise we show that, in order to prove the above locally uniform compactness and upper semi-continuity, no additional conditions are required, in which sense the two properties appear to be general properties satisfied by a large number of real models.
Adversity-driven changes in hypothalamic-pituitary-adrenal axis functioning during adolescence. The trails study.

PubMed

Laceulle, Odilia M; Nederhof, Esther; van Aken, Marcel A G; Ormel, Johan

2017-11-01

The hypothalamic-pituitary-adrenal (HPA) axis has been proposed to be a key mechanism underlying the link between adversity and mental health, but longitudinal studies on adversity and HPA-axis functioning are scarce. Here, we studied adversity-driven changes in HPA-axis functioning during adolescence (N=141). HPA-axis functioning (basal cortisol, cortisol awakening response, anticipation of, reaction to and recovery after a stress task) was measured twice, at age 16 and 19. Adversity (i.e., social defeat and loss/illness) since age 16 was measured extensively with the Life Stress Interview at age 19. Adolescents who reported being exposed to social defeat showed increases in basal cortisol (ɳ 2 =0.029) and decreases in reaction to the stress task (ɳ 2 =0.030) from age 16-19, compared to their peers in the loss/illness and no stress group. The current study provides unique longitudinal data on the role of adversity in HPA-axis functioning. Evidence is provided that adversity can affect the body's neuroendocrine response to stress, dependent on the nature of both the HPA-measures and adverse events under study. Copyright © 2017 Elsevier Ltd. All rights reserved.
Change in parent-child conflict and the HPA-axis: Where should we be looking and for how long?

PubMed Central

Kuhlman, Kate R.; Repetti, Rena L.; Reynolds, Bridget M.; Robles, Theodore F.

2017-01-01

Objective Salivary cortisol is increasingly used as a longitudinal indicator of change in neuroendocrine regulation and as a predictor of health outcomes in youth. The purpose of this study was to describe which indices of HPA-axis functioning are sensitive to changes in parent-child conflict over a three week period and to explore the time course under which these changes can be measured. Methods Youth (n = 47; ages 8–13) completed daily diaries of their conflict with parents for 56 days. On days 17–18 and 38–39, youth contributed saliva samples upon waking, 30-minutes post-waking, afternoon, and bedtime. We assessed change in average diurnal HPA-axis functioning between day 17–18 and day 38–39 as a function of the slopes of change in parent-child conflict over 3 weeks. Results Increasing parent-child conflict was positively associated with concurrent increases in total cortisol output (AUCg), flattening of the diurnal slope, and increases in cortisol at bedtime, but not with change in the cortisol awakening response (CAR). Further, associations between parent-child conflict and both AUCg and bedtime cortisol were observed with at least 14 days of daily diary reporting, whereas any additional ratings of conflict beyond 3 days of daily diaries did not improve model fit for changes in diurnal slope. Conclusions This study demonstrates the within-subject up-regulation of the HPA-axis across three weeks in a healthy sample of youth exposed to natural increases in family conflict. In particular, cortisol at bedtime may be the HPA-axis index that is most sensitive to change over time in parent-child conflict, above and beyond conflict occurring that day. Further, when testing associations between family stressors and diurnal cortisol, the optimal schedule for assessing parent-child conflict varies for different indices of HPA-axis functioning. PMID:26963373
Quality characteristics, structural changes, and storage stability of semi-dried noodles induced by moderate dehydration: understanding the quality changes in semi-dried noodles.

PubMed

Li, Man; Zhu, Ke-Xue; Sun, Qing-Jie; Amza, Tidjani; Guo, Xiao-Na; Zhou, Hui-Ming

2016-03-01

Based on the critical water content (for noodle deterioration) concluded previously, high-temperature-short-time (HTST; 105-135°C) and medium-temperature-long-time (MTLT; 45-75°C) dehydrations were introduced in this study to produce semi-dried noodles. The effects of HTST and MTLT on the quality parameters of semi-dried noodles, as well as noodle structure, storage stability, and changes in starch and protein components were thoroughly investigated. Differential scanning calorimeter (DSC) and birefringent analysis presented few starch gelatinization (approximately 30%) in HTST dehydrated noodles. Scanning electron microscopy (SEM) images showed more compact noodle surface, with uniform pores in the cross section, probably due to enhanced protein-starch combination after HTST dehydration. Meanwhile, HTST induced protein polymerizations in semi-dried noodles, mainly by -SH-S-S interchange, and resulted in significantly (P<0.05) reduced cooking loss. Furthermore, HTST noodles showed higher microbial and color stability. Shelf-life of dehydrated samples at 120°C was extended to 5days from 1day of the control. Copyright © 2015 Elsevier Ltd. All rights reserved.
Body shape transformation along a shared axis of anatomical evolution in labyrinth fishes (Anabantoidei).

PubMed

Collar, David C; Quintero, Michelle; Buttler, Bernardo; Ward, Andrea B; Mehta, Rita S

2016-03-01

Major morphological transformations, such as the evolution of elongate body shape in vertebrates, punctuate evolutionary history. A fundamental step in understanding the processes that give rise to such transformations is identification of the underlying anatomical changes. But as we demonstrate in this study, important insights can also be gained by comparing these changes to those that occur in ancestral and closely related lineages. In labyrinth fishes (Anabantoidei), rapid evolution of a highly derived torpedo-shaped body in the common ancestor of the pikehead (Luciocephalus aura and L. pulcher) occurred primarily through exceptional elongation of the head, with secondary contributions involving reduction in body depth and lengthening of the precaudal vertebral region. This combination of changes aligns closely with the primary axis of anatomical diversification in other anabantoids, revealing that pikehead evolution involved extraordinarily rapid change in structures that were ancestrally labile. Finer-scale examination of the anatomical components that determine head elongation also shows alignment between the pikehead evolutionary trajectory and the primary axis of cranial diversification in anabantoids, with much higher evolutionary rates leading to the pikehead. Altogether, our results show major morphological transformation stemming from extreme change along a shared morphological axis in labyrinth fishes. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.
Re-evaluating across-axis geochemical variations at the East Pacific Rise and Juan de Fuca Ridge: on- and off-axis melt delivery

NASA Astrophysics Data System (ADS)

Perfit, M. R.; Walters, R. L.

2014-12-01

High spatial density geochemical data sets from the N-EPR and S-JdFR are used to re-evaluate the across-axis geochemical variations in major and trace elements at mid-ocean ridges (MORs). At two axial melt lens (AML) segments, north and south, at the 9-10°N EPR, N-MORB MgO varies across-axis from the most primitive above the AML to more evolved away from the axis. This trend is distinct at the northern (magmatically more robust) segment with an axial MgO range of 8-9 wt% and off-axis (>2km) range of 6.5-8 wt%. This decrease is also reflected in E-MORB MgO variation. There is more variability at the southern segment but, off-axis progression to more evolved MgO is still evident. Interestingly, the Cleft segment, JdFR, displays similar geochemical behavior to the EPR with an axial MgO range of 7-8.5 wt% and off-axis (>2km) range of 6-7.5 wt%. EPR geochemical studies over the past 30 years have described models of upper crustal accumulation ranging from eruptions limited to the axis, to temporal variation in the composition of magma in the AML, to multiple eruption sites across the ridge crest and flanks (<5km). Eruptions limited to the axis, with topographically controlled flow off-axis, cannot reproduce the observed off-axis change to more evolved N-MORB. Time-dependence could explain one instance of evolved lavas off-axis but, similar geochemical behavior is observed at two separate AML segments. Multiple instances of consistent compositional variability at multiple AML segments, and at different ridges, point to a common process of crustal accretion at MORs. In light of recent geophysical discoveries of Off-axis AMLs (OAMLs) at the EPR and JdFR, we propose that the trend of more evolved lavas for the majority of N-MORB lavas with distance from the axis is controlled by thermal distribution in the underlying crystal mush zone (CMZ). Higher magma flux beneath the axis facilitates higher temperatures and high porosity melt pathways, reducing crustal residence times
Lifetime endogenous estrogen exposure and electrocardiographic frontal T axis changes in postmenopausal women.

PubMed

Atsma, Femke; van der Schouw, Yvonne T; Grobbee, Diederick E; Kors, Jan A; Bartelink, Marie-Louise E L

2009-08-20

The protective effect of endogenous estrogens in cardiovascular disease may in part originate from effects of circulating estrogens on the electrophysiological properties of the myocardium. The aim of this study was to investigate the relation between reproductive factors and the electrocardiographic frontal T axis in postmenopausal women. Cohort study. The study was conducted at the University Medical Center Utrecht. In total, 998 postmenopausal women were included. Information of women's reproductive life was obtained by a questionnaire. Electrocardiographic frontal T axes were categorized as normal (25-65 degrees) or abnormal (-180 degrees to 24 degrees and 66-180 degrees). Logistic regression analysis was used to assess the relationship between reproductive factors and the frontal T axis. Moreover, the effect of the lifetime cumulative number of menstrual cycles, a composite measure of all reproductive factors, on the frontal T axis was investigated. The mean age was 66.0 (+/-5.6) years and 15.3% had T-axes abnormalities. Later menopausal age decreased the risk on frontal T-axis abnormalities; the multivariable adjusted odds ratio was 0.97 (95% CI: 0.94-0.99) per year increasing menopause. For the lifetime cumulative number of menstrual cycles the age-adjusted odds ratio was 0.84 (95% CI: 0.75-0.99) per 100 menstrual cycles increase. Later age at menopause and increasing lifetime cumulative number of menstrual cycles decreased the risk on frontal T-axis changes. This supports the view that estrogens may protect against ventricular repolarization disturbances.
Detection of Yarkovsky acceleration in the context of precovery observations and the future Gaia catalogue

NASA Astrophysics Data System (ADS)

Desmars, J.

2015-03-01

Context. The Yarkovsky effect is a weak non-gravitational force leading to a small variation of the semi-major axis of an asteroid. Using radar measurements and astrometric observations, it is possible to measure a drift in semi-major axis through orbit determination. Aims: This paper aims to detect a reliable drift in semi-major axis of near-Earth asteroids (NEAs) from ground-based observations and to investigate the impact of precovery observations and the future Gaia catalogue in the detection of a secular drift in semi-major axis. Methods: We have developed a precise dynamical model of an asteroid's motion taking the Yarkovsky acceleration into account and allowing the fitting of the drift in semi-major axis. Using statistical methods, we investigate the quality and the robustness of the detection. Results: By filtering spurious detections with an estimated maximum drift depending on the asteroid's size, we found 46 NEAs with a reliable drift in semi-major axis in good agreement with the previous studies. The measure of the drift leads to a better orbit determination and constrains some physical parameters of these objects. Our results are in good agreement with the 1 /D dependence of the drift and with the expected ratio of prograde and retrograde NEAs. We show that the uncertainty of the drift mainly depends on the length of orbital arc and in this way we highlight the importance of the precovery observations and data mining in the detection of consistent drift. Finally, we discuss the impact of Gaia catalogue in the determination of drift in semi-major axis.
Acute myocardial infarction during l-thyroxine therapy in a patient with intermittent changing axis deviation, permanent atrial fibrillation and without significant coronary stenoses.

PubMed

Patanè, Salvatore; Marte, Filippo

2010-01-07

It has been rarely reported intermittent changing axis deviation also occurs during atrial fibrillation. Intermittent changing axis deviation during acute myocardial infarction and changing axis deviation associated with atrial fibrillation and acute myocardial infarction too have been also rarely reported. It has also been reported acute myocardial infarction during l-thyroxine substitution therapy in a patient with elevated levels of free triiodothyronine and without significant coronary artery stenoses. An acute myocardial infarction due to coronary spasm associated with l-thyroxine therapy has also been reported too. We present a case of changing axis deviation during acute myocardial infarction in a 56-year-old Italian woman with permanent atrial fibrillation and l-thyroxine therapy and without significant coronary stenoses. Also this case focuses attention on changing axis deviation in the presence of atrial fibrillation during acute myocardial infarction and on the possible development of acute myocardial infarction without significant coronary stenoses associated with l-thyroxine therapy.

Probability of major depression diagnostic classification using semi-structured versus fully structured diagnostic interviews.

PubMed

Levis, Brooke; Benedetti, Andrea; Riehm, Kira E; Saadat, Nazanin; Levis, Alexander W; Azar, Marleine; Rice, Danielle B; Chiovitti, Matthew J; Sanchez, Tatiana A; Cuijpers, Pim; Gilbody, Simon; Ioannidis, John P A; Kloda, Lorie A; McMillan, Dean; Patten, Scott B; Shrier, Ian; Steele, Russell J; Ziegelstein, Roy C; Akena, Dickens H; Arroll, Bruce; Ayalon, Liat; Baradaran, Hamid R; Baron, Murray; Beraldi, Anna; Bombardier, Charles H; Butterworth, Peter; Carter, Gregory; Chagas, Marcos H; Chan, Juliana C N; Cholera, Rushina; Chowdhary, Neerja; Clover, Kerrie; Conwell, Yeates; de Man-van Ginkel, Janneke M; Delgadillo, Jaime; Fann, Jesse R; Fischer, Felix H; Fischler, Benjamin; Fung, Daniel; Gelaye, Bizu; Goodyear-Smith, Felicity; Greeno, Catherine G; Hall, Brian J; Hambridge, John; Harrison, Patricia A; Hegerl, Ulrich; Hides, Leanne; Hobfoll, Stevan E; Hudson, Marie; Hyphantis, Thomas; Inagaki, Masatoshi; Ismail, Khalida; Jetté, Nathalie; Khamseh, Mohammad E; Kiely, Kim M; Lamers, Femke; Liu, Shen-Ing; Lotrakul, Manote; Loureiro, Sonia R; Löwe, Bernd; Marsh, Laura; McGuire, Anthony; Mohd Sidik, Sherina; Munhoz, Tiago N; Muramatsu, Kumiko; Osório, Flávia L; Patel, Vikram; Pence, Brian W; Persoons, Philippe; Picardi, Angelo; Rooney, Alasdair G; Santos, Iná S; Shaaban, Juwita; Sidebottom, Abbey; Simning, Adam; Stafford, Lesley; Sung, Sharon; Tan, Pei Lin Lynnette; Turner, Alyna; van der Feltz-Cornelis, Christina M; van Weert, Henk C; Vöhringer, Paul A; White, Jennifer; Whooley, Mary A; Winkley, Kirsty; Yamada, Mitsuhiko; Zhang, Yuying; Thombs, Brett D

2018-06-01

Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.AimsTo evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics. Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit. A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15-3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98-10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7-15) (OR = 0.96; 95% CI = 0.56-1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26-0.97). The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.Declaration of interestDrs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the
Maximizing the Semi-Major Axis for a Freely Coning Solar Sailcraft.

DTIC Science & Technology

1984-12-01

than ten degrees seem to be veil behaved and predictable in that there are no other local maxima within a 10’ radius of any given maxima. Convergence...and Mcdi. V.J.. " Analitical Evaluation of Solar Radiation Induced Orbital Perturbation of Space Structures" Journal of AstronaMUCIca Sincs Vol. XXV. No
Atrial fibrillation associated with exogenous subclinical hyperthyroidism, changing axis deviation, troponin-I positive and without acute coronary syndrome.

PubMed

Patanè, Salvatore; Marte, Filippo

2011-08-04

Changing axis deviation has been rarely reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been also rarely reported during acute myocardial infarction associated with atrial fibrillation or at the end of atrial fibrillation during acute myocardial infarction. Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. It has been reported that subclinical hyperthyroidism is not associated with coronary heart disease or mortality from cardiovascular causes but it is sufficient to induce arrhythmias including atrial fibrillation and atrial flutter. It has also been reported that increased factor X activity in patients with subclinical hyperthyroidism represents a potential hypercoagulable state. Serum troponin-I is a sensitive indicator of myocardial damage but abnormal troponin-I levels have been also reported without acute coronary syndrome and without cardiac damage. Abnormal troponin-I levels after supraventricular tachycardia have been also reported. We present a case of changing axis deviation in a 49-year-old Italian man with atrial fibrillation, exogenous subclinical hyperthyroidism and troponin-I positive without acute coronary syndrome. Also this case focuses attention on changing axis deviation, on subclinical hyperthyroidism and on the importance of a correct evaluation of abnormal troponin-I levels. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Research on electromechanical resonance of two-axis tracking system

NASA Astrophysics Data System (ADS)

Zhao, Zhi-ming; Xue, Ying-jie; Zeng, Shu-qin; Li, Zhi-guo

2017-02-01

The multi-axes synchronous system about the spatial two-axis turntable is the key equipment for semi-physical simulation and test in aerospace. In this paper, the whole structure design of the turntable is created by using Solidworks, then putting the three-dimensional solid model into ANSYS to build the finite element model. The software ANSYS is used to do the simulation about the static and dynamic analysis of two-axis turntable. Based on the modal analysis, we can forecast the inherent frequencies and the mode of vibration during the launch conditions which is very important to the design and safety of the structure.
The thyroid axis in ageing.

PubMed

Leitol, Holger; Behrends, Jens; Brabant, Georg

2002-01-01

The hypothalmo-pituitary thyroid axis, among various endocrine systems, undergoes physiological alterations associated with the ageing process. Directly age-related changes have to be distinguished from indirect modifications which are caused by simultaneous thyroidal or non-thyroidal illness or other physiological or pathophysiological states whose incidence increases with age. In summary, direct changes of the hypothalmo-pituitary-thyroid axis seem to be subtle and suggestive of a decreased hypothalamic stimulation of thyroid function. In parallel, disease-specific alterations such as the development of thyroid autonomy or changes in energy intake or sleep lead to pronounced alterations of thyroid function with age which may dominate the underlying ageing of the hypothalmo-pituitary thyroid axis itself. The following article attempts to delineate some aspects of the interplay of the regulation of thyroid function and the ageing process.
HPA axis reactivity to pharmacologic and psychological stressors in euthymic women with histories of postpartum versus major depression.

PubMed

Ferguson, Elizabeth H; Di Florio, Arianna; Pearson, Brenda; Putnam, Karen T; Girdler, Susan; Rubinow, David R; Meltzer-Brody, Samantha

2017-06-01

It is unclear whether women with a history of postpartum depression (PPD) have residual, abnormal hypothalamic-pituitary-adrenal (HPA) axis reactivity, as has been reported in major depression (MDD). Further unclear is whether the abnormalities in HPA axis reactivity associated with MDD represent a stable, underlying predisposition or a state-dependent phenomenon. This study sought the following: (1) to determine if euthymic postpartum women with a history of depression have an abnormal HPA axis reactivity to pharmacologic and psychological challenges and (2) to compare HPA reactivity in women with histories of PPD versus MDD. As a secondary objective, we wanted to determine the influence of trauma history on HPA axis function. Forty-five parous (12-24 months postpartum), euthymic women with history of MDD (n = 15), PPD (n = 15), and controls (n = 15) completed pharmacologic (dexamethasone/corticotropin-releasing hormone (CRH) test [DEX/CRH]) and psychological (Trier social stress test [TSST]) challenges during the luteal phase. Outcome measures were cortisol and adrenocorticotropic hormone (ACTH) response after DEX/CRH, and blood pressure, heart rate, epinephrine, norepinephrine, and cortisol response during the TSST. All groups had robust cortisol and ACTH response to DEX/CRH and cortisol response to TSST. Groups did not differ significantly in cortisol or ACTH response to DEX/CRH or in blood pressure, heart rate, epinephrine, norepinephrine, or cortisol response to TSST. Cortisol/ACTH ratio did not differ significantly between groups. Trauma history was associated with decreased cortisol response to DEX/CRH in women with histories of MDD, which was not significant after correction (F 8,125 , p = 0.02, Greenhouse-Geisser corrected p = 0.11). Currently euthymic women with histories of MDD or PPD did not demonstrate residual abnormal stress responsivity following administration of either a pharmacologic or psychological stressor.
Efficient reduction of defects in (1120) non-polar and (1122) semi-polar GaN grown on nanorod templates

NASA Astrophysics Data System (ADS)

Bai, J.; Gong, Y.; Xing, K.; Yu, X.; Wang, T.

2013-03-01

(1120) non-polar and (1122) semi-polar GaNs with a low defect density have been achieved by means of an overgrowth on nanorod templates, where a quick coalescence with a thickness even below 1 μm occurs. On-axis and off-axis X-ray rocking curve measurements have shown a massive reduction in the linewidth for our overgrown GaN in comparison with standard GaN films grown on sapphire substrates. Transmission electron microscope observation demonstrates that the overgrowth on the nanorod templates takes advantage of an omni-directional growth around the sidewalls of the nanostructures. The dislocations redirect in basal planes during the overgrowth, leading to their annihilation and termination at voids formed due to a large lateral growth rate. In the non-polar GaN, the priority <0001> lateral growth from vertical sidewalls of nanorods allows basal plane stacking faults (BSFs) to be blocked in the nanorod gaps; while for semi-polar GaN, the propagation of BSFs starts to be impeded when the growth front is changed to be along inclined <0001> direction above the nanorods.
Major threats of pollution and climate change to global coastal ecosystems and enhanced management for sustainability.

PubMed

Lu, Yonglong; Yuan, Jingjing; Lu, Xiaotian; Su, Chao; Zhang, Yueqing; Wang, Chenchen; Cao, Xianghui; Li, Qifeng; Su, Jilan; Ittekkot, Venugopalan; Garbutt, Richard Angus; Bush, Simon; Fletcher, Stephen; Wagey, Tonny; Kachur, Anatolii; Sweijd, Neville

2018-08-01

Coastal zone is of great importance in the provision of various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to high human populations and interactions between the land and ocean. Major threats of pollution from over enrichment of nutrients, increasing metals and persistent organic pollutants (POPs), and climate change have led to severe ecological degradation in the coastal zone, while few studies have focused on the combined impacts of pollution and climate change on the coastal ecosystems at the global level. A global overview of nutrients, metals, POPs, and major environmental changes due to climate change and their impacts on coastal ecosystems was carried out in this study. Coasts of the Eastern Atlantic and Western Pacific were hotspots of concentrations of several pollutants, and mostly affected by warming climate. These hotspots shared the same features of large populations, heavy industry and (semi-) closed sea. Estimation of coastal ocean capital, integrated management of land-ocean interaction in the coastal zone, enhancement of integrated global observation system, and coastal ecosystem-based management can play effective roles in promoting sustainable management of coastal marine ecosystems. Enhanced management from the perspective of mitigating pollution and climate change was proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.
A Free Wake Numerical Simulation for Darrieus Vertical Axis Wind Turbine Performance Prediction

NASA Astrophysics Data System (ADS)

Belu, Radian

2010-11-01

In the last four decades, several aerodynamic prediction models have been formulated for the Darrieus wind turbine performances and characteristics. We can identified two families: stream-tube and vortex. The paper presents a simplified numerical techniques for simulating vertical axis wind turbine flow, based on the lifting line theory and a free vortex wake model, including dynamic stall effects for predicting the performances of a 3-D vertical axis wind turbine. A vortex model is used in which the wake is composed of trailing stream-wise and shedding span-wise vortices, whose strengths are equal to the change in the bound vortex strength as required by the Helmholz and Kelvin theorems. Performance parameters are computed by application of the Biot-Savart law along with the Kutta-Jukowski theorem and a semi-empirical stall model. We tested the developed model with an adaptation of the earlier multiple stream-tube performance prediction model for the Darrieus turbines. Predictions by using our method are shown to compare favorably with existing experimental data and the outputs of other numerical models. The method can predict accurately the local and global performances of a vertical axis wind turbine, and can be used in the design and optimization of wind turbines for built environment applications.
Dynamical evolution of differentiated asteroid families

NASA Astrophysics Data System (ADS)

Martins-Filho, W. S.; Carvano, J.; Mothe-Diniz, T.; Roig, F.

2014-10-01

The project aims to study the dynamical evolution of a family of asteroids formed from a fully differentiated parent body, considering family members with different physical properties consistent with what is expected from the break up of a body formed by a metallic nucleus surrounded by a rocky mantle. Initially, we study the effects of variations in density, bond albedo, and thermal inertia in the semi-major axis drift caused by the Yarkovsky effect. The Yarkovsky effect is a non-conservative force caused by the thermal re-radiation of the solar radiation by an irregular body. In Solar System bodies, it is known to cause changes in the orbital motions (Peterson, 1976), eventually bringing asteroids into transport routes to near-Earth space, such as some mean motion resonances. We expressed the equations of variation of the semi-major axis directly in terms of physical properties (such as the mean motion, frequency of rotation, conductivity, thermal parameter, specific heat, obliquity and bond albedo). This development was based on the original formalism for the Yarkovsky effect (i.e., Bottke et al., 2006 and references therein). The derivation of above equations allowed us to closely study the variation of the semi-major axis individually for each physical parameter, clearly showing that the changes in semi-major axis for silicate bodies is twice or three times greater than for metal bodies. The next step was to calculate the orbital elements of a synthetic family after the break-up. That was accomplished assuming that the catastrophic disruption energy is given by the formalism described by Stewart and Leinhardt (2009) and assuming an isotropic distribution of velocities for the fragments of the nucleus and the mantle. Finally, the orbital evolution of the fragments is implemented using a simpletic integrator, and the result compared with the distribution of real asteroid families.
Competing effects of groundwater withdrawals and climate change on water availability in semi-arid India

NASA Astrophysics Data System (ADS)

Sishodia, R. P.; Shukla, S.

2017-12-01

India, a global leader in groundwater use (250 km3/yr), is experiencing groundwater depletion. There has been a 130-fold increase in number of irrigation wells since 1960. Anticipated future increase in groundwater demand is likely to exacerbate the water availability in the semi-arid regions of India. Depending on the direction of change, future climate change may either worsen or enhance the water availability. This study uses an integrated hydrologic modeling approach (MIKE SHE MIKE 11) to compare and combine the effects of future (2040-2069) increased groundwater withdrawals and climate change on surface and groundwater flows and availability for an agricultural watershed in semi-arid south India. Modeling results showed that increased groundwater withdrawals in the future resulted in reduced surface flows (25%) and increased frequency and duration (90 days/yr) of well drying. In contrast, projected future increase in rainfall (7-43%) under the changed climate showed increased groundwater recharge (15-67%) and surface flows (9-155%). Modeling results suggest that the positive effects of climate change may enhance the water availability in this semi-arid region of India. However, in combination with increased withdrawals, climate change was shown to increase the well drying and reduce the water availability especially during dry years. A combination of management options such as flood to drip conversion, energy subsidy reductions and water storage can support increased groundwater irrigated area in the future while mitigating the well drying. A cost-benefit analysis showed that dispersed water storage and flood to drip conversion can be highly cost-effective in this semi-arid region. The study results suggest that the government and management policies need to be focused towards an integrated management of demand and supply to create a sustainable food-water-energy nexus in the region.
Changes in the three-dimensional load-bearing axis after mobile-bearing total knee arthroplasty.

PubMed

Ishii, Yoshinori; Noguchi, Hideo; Sato, Junko; Ezawa, Nobukazu; Toyabe, Shin-Ichi

2016-07-01

The purpose of this study was to assess changes in the three-dimensional (3D) load-bearing mechanical axis (LBMA) preoperatively and at 3 weeks and more than 1-year follow-up after total knee arthroplasty (TKA), and effects of the degree of constraint in the anteroposterior (AP) direction because of the retention of the posterior cruciate ligament (PCL) and the implant design on the changes in LBMA. We evaluated 157 knees from 131 patients, including 79 knees that received meniscal-bearing-type (PCL-retaining) and 78 knees that received rotating-platform-type (PCL-substituting) prostheses. Quantitative 3D computed tomography was used to assess changes in the location of the pre- and postoperative LBMA at the tibial plateau level. Changes in the 3D axis were mainly found from medial to lateral and posterior to anterior in both implant designs with no significant differences. Change in the mediolateral (ML) direction was improved soon after TKA, but change in the AP direction improved more gradually over time. The different constraints in the AP direction because of the retention of the PCL and different implant designs did not affect the changes in the LBMA. The LBMA in the AP direction more than 1 year postoperatively, as well as the LBMA in the ML direction at 3 weeks, appears to shift toward the location found in normal knees after TKA, regardless of the type of prosthetic constraint. These changes may be an important factor that influences the periarticular knee bone mineral density which load bearing may be related to. Level II, Prognostic study.
A Morphospace for Reef Fishes: Elongation Is the Dominant Axis of Body Shape Evolution

PubMed Central

Claverie, Thomas; Wainwright, Peter C.

2014-01-01

Tropical reef fishes are widely regarded as being perhaps the most morphologically diverse vertebrate assemblage on earth, yet much remains to be discovered about the scope and patterns of this diversity. We created a morphospace of 2,939 species spanning 56 families of tropical Indo-Pacific reef fishes and established the primary axes of body shape variation, the phylogenetic consistency of these patterns, and whether dominant patterns of shape change can be accomplished by diverse underlying changes. Principal component analysis showed a major axis of shape variation that contrasts deep-bodied species with slender, elongate forms. Furthermore, using custom methods to compare the elongation vector (axis that maximizes elongation deformation) and the main vector of shape variation (first principal component) for each family in the morphospace, we showed that two thirds of the families diversify along an axis of body elongation. Finally, a comparative analysis using a principal coordinate analysis based on the angles among first principal component vectors of each family shape showed that families accomplish changes in elongation with a wide range of underlying modifications. Some groups such as Pomacentridae and Lethrinidae undergo decreases in body depth with proportional increases in all body regions, while other families show disproportionate changes in the length of the head (e.g., Labridae), the trunk or caudal region in all combinations (e.g., Pempheridae and Pinguipedidae). In conclusion, we found that evolutionary changes in body shape along an axis of elongation dominates diversification in reef fishes. Changes in shape on this axis are thought to have immediate implications for swimming performance, defense from gape limited predators, suction feeding performance and access to some highly specialized habitats. The morphological modifications that underlie changes in elongation are highly diverse, suggesting a role for a range of developmental processes
A morphospace for reef fishes: elongation is the dominant axis of body shape evolution.

PubMed

Claverie, Thomas; Wainwright, Peter C

2014-01-01

Tropical reef fishes are widely regarded as being perhaps the most morphologically diverse vertebrate assemblage on earth, yet much remains to be discovered about the scope and patterns of this diversity. We created a morphospace of 2,939 species spanning 56 families of tropical Indo-Pacific reef fishes and established the primary axes of body shape variation, the phylogenetic consistency of these patterns, and whether dominant patterns of shape change can be accomplished by diverse underlying changes. Principal component analysis showed a major axis of shape variation that contrasts deep-bodied species with slender, elongate forms. Furthermore, using custom methods to compare the elongation vector (axis that maximizes elongation deformation) and the main vector of shape variation (first principal component) for each family in the morphospace, we showed that two thirds of the families diversify along an axis of body elongation. Finally, a comparative analysis using a principal coordinate analysis based on the angles among first principal component vectors of each family shape showed that families accomplish changes in elongation with a wide range of underlying modifications. Some groups such as Pomacentridae and Lethrinidae undergo decreases in body depth with proportional increases in all body regions, while other families show disproportionate changes in the length of the head (e.g., Labridae), the trunk or caudal region in all combinations (e.g., Pempheridae and Pinguipedidae). In conclusion, we found that evolutionary changes in body shape along an axis of elongation dominates diversification in reef fishes. Changes in shape on this axis are thought to have immediate implications for swimming performance, defense from gape limited predators, suction feeding performance and access to some highly specialized habitats. The morphological modifications that underlie changes in elongation are highly diverse, suggesting a role for a range of developmental processes
An FGF3-BMP Signaling Axis Regulates Caudal Neural Tube Closure, Neural Crest Specification and Anterior-Posterior Axis Extension

PubMed Central

Anderson, Matthew J.; Schimmang, Thomas; Lewandoski, Mark

2016-01-01

During vertebrate axis extension, adjacent tissue layers undergo profound morphological changes: within the neuroepithelium, neural tube closure and neural crest formation are occurring, while within the paraxial mesoderm somites are segmenting from the presomitic mesoderm (PSM). Little is known about the signals between these tissues that regulate their coordinated morphogenesis. Here, we analyze the posterior axis truncation of mouse Fgf3 null homozygotes and demonstrate that the earliest role of PSM-derived FGF3 is to regulate BMP signals in the adjacent neuroepithelium. FGF3 loss causes elevated BMP signals leading to increased neuroepithelium proliferation, delay in neural tube closure and premature neural crest specification. We demonstrate that elevated BMP4 depletes PSM progenitors in vitro, phenocopying the Fgf3 mutant, suggesting that excessive BMP signals cause the Fgf3 axis defect. To test this in vivo we increased BMP signaling in Fgf3 mutants by removing one copy of Noggin, which encodes a BMP antagonist. In such mutants, all parameters of the Fgf3 phenotype were exacerbated: neural tube closure delay, premature neural crest specification, and premature axis termination. Conversely, genetically decreasing BMP signaling in Fgf3 mutants, via loss of BMP receptor activity, alleviates morphological defects. Aberrant apoptosis is observed in the Fgf3 mutant tailbud. However, we demonstrate that cell death does not cause the Fgf3 phenotype: blocking apoptosis via deletion of pro-apoptotic genes surprisingly increases all Fgf3 defects including causing spina bifida. We demonstrate that this counterintuitive consequence of blocking apoptosis is caused by the increased survival of BMP-producing cells in the neuroepithelium. Thus, we show that FGF3 in the caudal vertebrate embryo regulates BMP signaling in the neuroepithelium, which in turn regulates neural tube closure, neural crest specification and axis termination. Uncovering this FGF3-BMP signaling axis is
Axis of Eye Rotation Changes with Head-Pitch Orientation during Head Impulses about Earth-Vertical

PubMed Central

Schubert, Michael C.; Clendaniel, Richard A.; Carey, John P.; Della Santina, Charles C.; Minor, Lloyd B.; Zee, David S.

2006-01-01

The goal of this study was to assess how the axis of head rotation, Listing's law, and eye position influence the axis of eye rotation during brief, rapid head rotations. We specifically asked how the axis of eye rotation during the initial angular vestibuloocular reflex (VOR) changed when the pitch orientation of the head relative to Earth-vertical was varied, but the initial position of the eye in the orbit and the orientation of Listing's plane with respect to the head were fixed. We measured three-dimensional eye and head rotation axes in eight normal humans using the search coil technique during head-and-trunk (whole-body) and head-on-trunk (head-only) “impulses” about an Earth-vertical axis. The head was initially oriented at one of five pitch angles (30° nose down, 15° nose down, 0°, 15° nose up, 30° nose up). The fixation target was always aligned with the nasooccipital axis. Whole-body impulses were passive, unpredictable, manual, rotations with peak-amplitude of ∼20°, peak-velocity of ∼80°/s, and peak-acceleration of ∼1000°/s2. Head-only impulses were also passive, unpredictable, manual, rotations with peak-amplitude of ∼20°, peak-velocity of ∼150°/s, and peak-acceleration of ∼3000°/s2. During whole-body impulses, the axis of eye rotation tilted in the same direction, and by an amount proportional (0.51 ± 0.09), to the starting pitch head orientation (P < 0.05). This proportionality constant decreased slightly to 0.39 ± 0.08 (P < 0.05) during head-only impulses. Using the head-only impulse data, with the head pitched up, we showed that only 50% of the tilt in the axis of eye rotation could be predicted from vectorial summation of the gains (eye velocity/head velocity) obtained for rotations about the pure yaw and roll head axes. Thus, even when the orientation of Listing's plane and eye position in the orbit are fixed, the axis of eye rotation during the VOR reflects a compromise between the requirements of Listing's law and a
How will the semi-natural vegetation of the UK have changed by 2030 given likely changes in nitrogen deposition?

PubMed

Stevens, Carly J; Payne, Richard J; Kimberley, Adam; Smart, Simon M

2016-01-01

Nitrogen deposition is known to have major impacts on contemporary ecosystems but few studies have addressed how these impacts will develop over coming decades. We consider likely changes to British semi-natural vegetation up to the year 2030 both qualitatively, based on knowledge of species responses from experimental and gradient studies, and quantitatively, based on modelling of species relationships in national monitoring data. We used historical N deposition trends and national predictions of changing deposition to calculate cumulative deposition from 1900 to 2030. Data from the Countryside Survey (1978, 1990 and 1998) was used to parameterise models relating cumulative N deposition to Ellenberg N which were then applied to expected future deposition trends. Changes to habitat suitability for key species of grassland, heathland and bog, and broadleaved woodland to 2030 were predicted using the MultiMOVE model. In UK woodlands by 2030 there is likely to be reduced occurrence of lichens, increased grass cover and a shift towards more nitrophilic vascular plant species. In grasslands we expect changing species composition with reduced occurrence of terricolous lichens and, at least in acid grasslands, reduced species richness. In heaths and bogs we project overall reductions in species richness with decreased occurrence of terricolous lichens and some bryophytes, reduced cover of dwarf shrubs and small increases in grasses. Our study clearly suggests that changes in vegetation due to nitrogen deposition are likely to continue through coming decades. Copyright © 2015 Elsevier Ltd. All rights reserved.
Semi-transparent solar cells

NASA Astrophysics Data System (ADS)

Sun, J.; Jasieniak, J. J.

2017-03-01

Semi-transparent solar cells are a type of technology that combines the benefits of visible light transparency and light-to-electricity conversion. One of the biggest opportunities for such technologies is in their integration as windows and skylights within energy-sustainable buildings. Currently, such building integrated photovoltaics (BIPV) are dominated by crystalline silicon based modules; however, the opaque nature of silicon creates a unique opportunity for the adoption of emerging photovoltaic candidates that can be made truly semi-transparent. These include: amorphous silicon-, kesterite-, chalcopyrite-, CdTe-, dye-sensitized-, organic- and perovskite- based systems. For the most part, amorphous silicon has been the workhorse in the semi-transparent solar cell field owing to its established, low-temperature fabrication processes. Excitement around alternative classes, particularly perovskites and the inorganic candidates, has recently arisen because of the major efficiency gains exhibited by these technologies. Importantly, each of these presents unique opportunities and challenges within the context of BIPV. This topic review provides an overview into the broader benefits of semi-transparent solar cells as building-integrated features, as well as providing the current development status into all of the major types of semi-transparent solar cells technologies.
Stochastic orbital migration of small bodies in Saturn's rings

NASA Astrophysics Data System (ADS)

Rein, H.; Papaloizou, J. C. B.

2010-12-01

Many small moonlets that create propeller structures have been found in Saturn's rings by the Cassini spacecraft. We study the dynamical evolution of such 20-50 m sized bodies, which are embedded in Saturn's rings. We estimate the importance of various interaction processes with the ring particles on the moonlet's eccentricity and semi-major axis analytically. For low ring surface densities, the main effects on the evolution of the eccentricity and the semi-major axis are found to be caused by collisions and the gravitational interaction with particles in the vicinity of the moonlet. For high surface densities, the gravitational interaction with self-gravity wakes becomes important. We also perform realistic three-dimensional, collisional N-body simulations with up to a quarter of a million particles. A new set of pseudo shear periodic boundary conditions is used, which reduces the computational costs by an order of magnitude compared to previous studies. Our analytic estimates are confirmed to within a factor of two. On short timescales the evolution is always dominated by stochastic effects caused by collisions and gravitational interaction with self-gravitating ring particles. These result in a random walk of the moonlet's semi-major axis. The eccentricity of the moonlet quickly reaches an equilibrium value owing to collisional damping. The average change in semi-major axis of the moonlet after 100 orbital periods is 10-100m. This translates to an offset in the azimuthal direction of several hundred kilometres. We expect that such a shift is easily observable. Two movies are only available in electronic form at http://www.aanda.org
Temporal dynamics of the HPA axis linked to exploratory behavior in a wild European songbird (Parus major).

PubMed

Baugh, Alexander T; Davidson, Sarah C; Hau, Michaela; van Oers, Kees

2017-09-01

Variation in the reactivity of the endocrine stress axis is thought to underlie aspects of persistent individual differences in behavior (i.e. animal personality). Previous studies, however, have focused largely on estimating baseline or peak levels of glucocorticoids (CORT), often in captive animals. In contrast, the temporal dynamics of the HPA axis-how quickly it turns on and off, for example-may better indicate how an individual copes with stressors. Moreover, these HPA components might be correlated, thereby representing endocrine suites. Using wild-caught great tits (Parus major) we tested birds for exploratory behavior using a standardized novel environment assay that serves as a validated proxy for personality. We then re-captured a subset of these birds (n=85) and characterized four components of HPA physiology: baseline, endogenous stress response, a dexamethasone (DEX) challenge to estimate the strength of negative feedback, and an adrenocorticotropic hormone (ACTH) challenge to estimate adrenal capacity. We predicted that these four HPA responses would be positively correlated and that less exploratory birds would have a more rapid onset of the stress response (a CORT elevation during the baseline bleed) and weaker negative feedback (higher CORT after DEX). We found support for the first two predictions but not the third. All four components were positively correlated with each other and less exploratory birds exhibited an elevation in CORT during the baseline bleed (<3min from capture). Less exploratory birds, however, did not exhibit weaker negative feedback following the DEX challenge, but did exhibit weaker adrenal capacity. Together, our findings provide partial support for the hypothesis that the temporal reactivity of the HPA axis is linked with consistent individual differences in behavior, with more cautious (slower exploring) individuals exhibiting a faster CORT response. Copyright © 2017 Elsevier Inc. All rights reserved.

Extreme climatic events change the dynamics and invasibility of semi-arid annual plant communities.

PubMed

Jiménez, Milagros A; Jaksic, Fabian M; Armesto, Juan J; Gaxiola, Aurora; Meserve, Peter L; Kelt, Douglas A; Gutiérrez, Julio R

2011-12-01

Extreme climatic events represent disturbances that change the availability of resources. We studied their effects on annual plant assemblages in a semi-arid ecosystem in north-central Chile. We analysed 130 years of precipitation data using generalised extreme-value distribution to determine extreme events, and multivariate techniques to analyse 20 years of plant cover data of 34 native and 11 exotic species. Extreme drought resets the dynamics of the system and renders it susceptible to invasion. On the other hand, by favouring native annuals, moderately wet events change species composition and allow the community to be resilient to extreme drought. The probability of extreme drought has doubled over the last 50 years. Therefore, investigations on the interaction of climate change and biological invasions are relevant to determine the potential for future effects on the dynamics of semi-arid annual plant communities. 2011 Blackwell Publishing Ltd/CNRS.
Efficient reduction of defects in (1120) non-polar and (1122) semi-polar GaN grown on nanorod templates

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

Bai, J.; Gong, Y.; Xing, K.

2013-03-11

(1120) non-polar and (1122) semi-polar GaNs with a low defect density have been achieved by means of an overgrowth on nanorod templates, where a quick coalescence with a thickness even below 1 {mu}m occurs. On-axis and off-axis X-ray rocking curve measurements have shown a massive reduction in the linewidth for our overgrown GaN in comparison with standard GaN films grown on sapphire substrates. Transmission electron microscope observation demonstrates that the overgrowth on the nanorod templates takes advantage of an omni-directional growth around the sidewalls of the nanostructures. The dislocations redirect in basal planes during the overgrowth, leading to their annihilationmore » and termination at voids formed due to a large lateral growth rate. In the non-polar GaN, the priority <0001> lateral growth from vertical sidewalls of nanorods allows basal plane stacking faults (BSFs) to be blocked in the nanorod gaps; while for semi-polar GaN, the propagation of BSFs starts to be impeded when the growth front is changed to be along inclined <0001> direction above the nanorods.« less
Virtual prototyping of a semi-active transfemoral prosthetic leg.

PubMed

Lui, Zhen Wei; Awad, Mohammed I; Abouhossein, Alireza; Dehghani-Sanij, Abbas A; Messenger, Neil

2015-05-01

This article presents a virtual prototyping study of a semi-active lower limb prosthesis to improve the functionality of an amputee during prosthesis-environment interaction for level ground walking. Articulated ankle-foot prosthesis and a single-axis semi-active prosthetic knee with active and passive operating modes were considered. Data for level ground walking were collected using a photogrammetric method in order to develop a base-line simulation model and with the hip kinematics input to verify the proposed design. The simulated results show that the semi-active lower limb prosthesis is able to move efficiently in passive mode, and the activation time of the knee actuator can be reduced by approximately 50%. Therefore, this semi-active system has the potential to reduce the energy consumption of the actuators required during level ground walking and requires less compensation from the amputee due to lower deviation of the vertical excursion of body centre of mass. © IMechE 2015.
Scale-relativity and quantization of exoplanet orbital semi-major axes

NASA Astrophysics Data System (ADS)

Nottale, L.; Schumacher, G.; Lefèvre, E. T.

2000-09-01

In a recent study (Nottale \\cite{xtrasol}), it was found that the distribution of the semi-major axes of the firstly discovered exoplanets was clustered around quantized values according to the law a/GM=(n/w02, in the same manner and in terms of the same constant w0=144 km/s as in our own inner Solar System. The ratio alpha g=w0/c actually stands out as a gravitational coupling constant. The number of exoplanets has now increased fivefold since this first study, including a full system of three planets around Ups And. In the present paper, we apply the same analysis to the new exoplanets and we find that their distribution agrees with this structuration law in a statistically significant way (probability ~ 10-4). Such a n2 law is predicted by the scale-relativity approach to planetary system formation, in which the evolution of planetesimals is described in terms of a generalized Schrödinger equation. In particular, one was able to predict from this model (Nottale \\cite{liwos}) the occurrence of preferential distances of planets at ~ 0.043 AU/Msun and ~ 0.17 AU/Msun from their parent stars. The observational data supports this theoretical prediction, since the semimajor axes of ~ 50% of the presently known exoplanets cluster around these values (51 Peg-type planets).
Simulating the hydrologic impacts of land-cover and climate changes in a semi-arid watershed

EPA Science Inventory

Changes in climate and land cover are principal variables affecting watershed hydrology. This paper uses a cell-based model to examine the hydrologic impacts of climate and land cover changes in the semi-arid Lower Virgin River (LVR) watershed located upstream of Lake Mead, Nevad...
Interleukin-6 production and deregulation of the hypothalamic-pituitary-adrenal axis in patients with major depressive disorders.

PubMed

Humphreys, Derek; Schlesinger, Liana; Lopez, Marcelo; Araya, A Verónica

2006-12-01

The present study was designed to determine whether an association exists between HPA activity and cytokine production in major depression (MD). In 9 patients with MD and 11 control subjects of both sexes, all drug-free, activity of the HPA axis was evaluated by circadian rhythm of plasma cortisol, 24-h free urinary cortisol, an overnight 1 mg dexamethasone suppression test, and an oCRF stimulation test. Spontaneous and LPS-stimulated production of IL-1beta, IL-6, and TNFalpha by peripheral blood mononuclear cells were also determined. We found a significantly elevated spontaneous production of IL-6 in patients with MD (3541.2 +/- 726.8 vs 380.4 +/- 77.5 pg/mL in controls, p < 0.05), while LPS-stimulated production was significantly lower in patients than in control subjects (19,867.7 +/- 3649.2 vs 33,142.2 +/- 15,47.2 pg/mL, p < 0.05). The adrenocorticotropic hormone response to oCRF, evaluated as the area under the curve (AUCACTH) was significantly lower in patients than in control subjects (p = 0.02). A positive correlation between AUCACTH and LPS-stimulated IL-6 secretion was observed in patients with MD (r = 0.75, p < 0.05) but not in controls. These findings suggest that the activation of the inflammatory response described in depression might be associated with long-term hyperactivity of the HPA axis.
The SZ-5 Spaceship Orbit Changes During The 2003 "Halloween Storm"

NASA Astrophysics Data System (ADS)

Huang, C.; Liu, D.; Guo, J.

2017-12-01

We analyse the daily major semi-axis variations of SZ-5 (ShenZhou V) spaceship during Oct. 20 to Dec. 30 in 2003, which includes the period of the 2003 "Halloween Storm". The significant orbital decay has been observed in late October due to the great solar flares and the severe geomagnetic storms. According to the equation of the air-drag-force on a spacecraft and the SZ-5 orbital decay information, we derive the thermospheric density relative changes during the 2003 "Halloween Storm" and compare the results with the Naval Research Laboratory Mass Spectrometer Incoherent Scatter Radar Extended Model (NRLMSISE-00). The analyses show that the thermosperic density (at the altitude of SZ-5, about 350 km) in storm time enchances to approximately three times as much as that in the quiet time but the empirical model may underestimate the thermospheric density changes during this severe storm.
HPA axis hyperactivity and attempted suicide in young adult mood disorder inpatients.

PubMed

Jokinen, Jussi; Nordström, Peter

2009-07-01

Hyperactivity of the Hypothalamic-Pituitary-Adrenal (HPA) axis is a consistent finding in Major Depressive Disorder (MDD) and most prospective studies of HPA-axis function have found that non-suppressors in the dexamethasone suppression test (DST) are more likely to commit suicide during follow-up. The results of studies on HPA-axis function and attempted suicide are less consistent. Suicide attempts are more common among young people than the elderly, whereas suicide is more common among the elderly. The impact of age related changes in HPA-axis system activity in relation to suicidal behaviour across the lifecycle may be of importance. The aim of the present study was to investigate the DST results in 36 young adult (30 years or younger) inpatients with mood disorder, with (n=18) and without suicide attempt at the index episode. The DST non-suppressor rate was 25% among young mood disorder inpatients. DST non-suppression was associated with suicide attempt and post-dexamethasone serum cortisol at 11:00 p.m. was significantly higher in suicide attempters compared to non-attempters. The DST non-suppressor rate was 39% in young adult suicide attempters compared with 11% in non-attempters. The results add to previous evidence in support of the role of HPA axis hyperactivity and suicidal behaviour. The present findings motivate to include HPA axis measures in the assessment of depression in young adults.
Research of misalignment between dithered ring laser gyro angle rate input axis and dither axis

NASA Astrophysics Data System (ADS)

Li, Geng; Wu, Wenqi; FAN, Zhenfang; LU, Guangfeng; Hu, Shaomin; Luo, Hui; Long, Xingwu

2014-12-01

The strap-down inertial navigation system (SINS), especially the SINS composed by dithered ring laser gyroscope (DRLG) is a kind of equipment, which providing high reliability and performance for moving vehicles. However, the mechanical dither which is used to eliminate the "Lock-In" effect can cause vibration disturbance to the INS and lead to dithering coupling problem in the inertial measurement unit (IMU) gyroscope triad, so its further application is limited. Among DRLG errors between the true gyro rotation rate and the measured rotation rate, the frequently considered one is the input axis misalignment between input reference axis which is perpendicular to the mounting surface and gyro angular rate input axis. But the misalignment angle between DRLG dither axis and gyro angular rate input axis is often ignored by researchers, which is amplified by dither coupling problem and that would lead to negative effects especially in high accuracy SINS. In order to study the problem more clearly, the concept of misalignment between DRLG dither axis and gyro angle rate input axis is researched. Considering the error of misalignment is of the order of 10-3 rad. or even smaller, the best way to measure it is using DRLG itself by means of an angle exciter as an auxiliary. In this paper, the concept of dither axis misalignment is explained explicitly firstly, based on this, the frequency of angle exciter is induced as reference parameter, when DRLG is mounted on the angle exciter in a certain angle, the projections of angle exciter rotation rate and mechanical oscillation rate on the gyro input axis are both sensed by DRLG. If the dither axis has misalignment error with the gyro input axis, there will be four major frequencies detected: the frequency of angle exciter, the dither mechanical frequency, sum and difference frequencies of the former two frequencies. Then the amplitude spectrum of DRLG output signal obtained by the using LabVIEW program. if there are only angle
Chronic ACTH autoantibodies are a significant pathological factor in the disruption of the hypothalamic-pituitary-adrenal axis in chronic fatigue syndrome, anorexia nervosa and major depression.

PubMed

Wheatland, R

2005-01-01

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is a commonly recognized feature of many pathological conditions. Abnormal adrenal responses to experimental manipulation have been well documented in patients suffering from chronic fatigue syndrome, anorexia nervosa and major depression. Yet no defect of any single organ, gland or brain region has been identified as a cause of these abnormalities. The disruption of the HPA axis that occurs in these conditions can be understood if an interfering factor is present in these patients. Evidence indicates that this interfering factor is adrenocorticotropin hormone (ACTH) autoantibodies. Chronic high levels of ACTH autoantibodies will significantly disrupt the HPA axis and force the body to compensate for an impaired cortisol response. The resulting effect of chronic ACTH autoantibody interference is the manifestation of adrenocortical insufficient symptoms and psychological disturbances. Some symptoms of chronic fatigue syndrome, anorexia nervosa and major depression, such as anxiety, are the adverse effects of mechanisms compensating for less effective ACTH due to autoantibodies. Furthermore, these patients engage in extraordinary behaviors, such as self-injury, to increase their cortisol levels. When this compensation is inadequate, symptoms of adrenocortical insufficiency appear. Corticosteroid supplements have been demonstrated to be an effective treatment for chronic fatigue syndrome, anorexia nervosa and major depression. It allows the patients to have the corticosteroids they require for daily functioning and daily stressors. This therapy will relieve the patients of their symptoms of adrenocortical insufficiency and permit their cortisol-stimulating mechanisms to operate at levels that will not cause pathological problems.
Neospora caninum in Axis Deer ( Axis axis ) and Fallow Deer ( Dama dama ) in Northern Mexico.

PubMed

De La Torre, Jose R; Bautista-Piña, Christian; Alfonso Ortega-S, J; Cantu-Covarruvias, Antonio; Genoveva Alvarez-Ojeda, Maria; Romero-Salas, Dora; Henke, Scott E; Hilton, Clayton D; Hewitt, David G; De Young, Randy W; Campbell, Tyler A; Bryant, Fred C

2017-01-01

Serum samples from 18 axis deer ( Axis axis ) and 19 fallow deer ( Dama dama ) were analyzed with an enzyme-linked immunosorbent assay for Neospora caninum antibodies. Two axis (11%) and two fallow deer (11%) were positive for N. caninum antibodies.
From the Bottom-Up: Chemotherapy and Gut-Brain Axis Dysregulation.

PubMed

Bajic, Juliana E; Johnston, Ian N; Howarth, Gordon S; Hutchinson, Mark R

2018-01-01

The central nervous system and gastrointestinal tract form the primary targets of chemotherapy-induced toxicities. Symptoms associated with damage to these regions have been clinically termed chemotherapy-induced cognitive impairment and mucositis. Whilst extensive literature outlines the complex etiology of each pathology, to date neither chemotherapy-induced side-effect has considered the potential impact of one on the pathogenesis of the other disorder. This is surprising considering the close bidirectional relationship shared between each organ; the gut-brain axis. There are complex multiple pathways linking the gut to the brain and vice versa in both normal physiological function and disease. For instance, psychological and social factors influence motility and digestive function, symptom perception, and behaviors associated with illness and pathological outcomes. On the other hand, visceral pain affects central nociception pathways, mood and behavior. Recent interest highlights the influence of functional gut disorders, such as inflammatory bowel diseases and irritable bowel syndrome in the development of central comorbidities. Gut-brain axis dysfunction and microbiota dysbiosis have served as key portals in understanding the potential mechanisms associated with these functional gut disorders and their effects on cognition. In this review we will present the role gut-brain axis dysregulation plays in the chemotherapy setting, highlighting peripheral-to-central immune signaling mechanisms and their contribution to neuroimmunological changes associated with chemotherapy exposure. Here, we hypothesize that dysregulation of the gut-brain axis plays a major role in the intestinal, psychological and neurological complications following chemotherapy. We pay particular attention to evidence surrounding microbiota dysbiosis, the role of intestinal permeability, damage to nerves of the enteric and peripheral nervous systems and vagal and humoral mediated changes.
Horizontal-axis clothes washer market poised for expansion

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

George, K.L.

1994-12-31

The availability of energy- and water-efficient horizontal-axis washing machines in the North American market is growing, as US and European manufacturers position for an expected long-term market shift toward horizontal-axis (H-axis) technology. Four of the five major producers of washing machines in the US are developing or considering new H-axis models. New entrants, including US-based Staber Industries and several European manufacturers, are also expected to compete in this market. The intensified interest in H-axis technology is partly driven by speculation that new US energy efficiency standards, to be proposed in 1996 and implemented in 1999, will effectively mandate H-axis machines.more » H-axis washers typically use one-third to two-thirds less energy, water, and detergent than vertical-axis machines. Some models also reduce the energy needed to dry the laundry, since their higher spin speeds extract more water than is typical with vertical-axis designs. H-axis washing machines are the focus of two broadly-based efforts to support coordinated research and incentive programs by electric, gas, and water utilities: The High-Efficiency Laundry Metering/Marketing Analysis (THELMA), and the Consortium for Energy Efficiency (CEE) High-Efficiency Clothes Washer Initiative. These efforts may help to pave the way for new types of marketing partnerships among utilities and other parties that could help to speed adoption of H-axis washers.« less
Polymer matrix of fiber-reinforced composites: Changes in the semi-interpenetrating polymer network during the shelf life.

PubMed

Khan, Aftab A; Al-Kheraif, Abdulaziz A; Al-Shehri, Abdullah M; Säilynoja, Eija; Vallittu, Pekka K

2018-02-01

This laboratory study was aimed to characterize semi-interpenetrating polymer network (semi-IPN) of fiber-reinforced composite (FRC) prepregs that had been stored for up to two years before curing. Resin impregnated prepregs of everStick C&B (StickTech-GC, Turku, Finland) glass FRC were stored at 4°C for various lengths of time, i.e., two-weeks, 6-months and 2-years. Five samples from each time group were prepared with a light initiated free radical polymerization method, which were embedded to its long axis in self-curing acrylic. The nanoindentation readings on the top surface toward the core of the sample were made for five test groups, which were named as "stage 1-5". To evaluate the nanohardness and modulus of elasticity of the polymer matrix, a total of 4 slices (100µm each) were cut from stage 1 to stage 5. Differences in nanohardness values were evaluated with analysis of variance (ANOVA), and regression model was used to develop contributing effect of the material's different stages to the total variability in the nanomechanical properties. Additional chemical and thermal characterization of the polymer matrix structure of FRC was carried out. It was hypothesized that time of storage may have an influence on the semi-IPN polymer structure of the cured FRC. The two-way ANOVA test revealed that the storage time had no significant effect on the nanohardness of FRC (p = 0.374). However, a highly significant difference in nanohardness values was observed between the different stages of FRC (P<0.001). The regression coefficient suggests nanohardness increased on average by 0.039GPa for every storage group. The increased nanohardness values in the core region of 6-months and 2-years stored prepregs might be due to phase-segregation of components of semi-IPN structure of FRC prepregs before their use. This may have an influence to the surface bonding properties of the cured FRC. Copyright © 2017 Elsevier Ltd. All rights reserved.
Cross-axis adaptation of torsional components in the yaw-axis vestibulo-ocular reflex

NASA Technical Reports Server (NTRS)

Trillenberg, P.; Shelhamer, M.; Roberts, D. C.; Zee, D. S.

2003-01-01

The three pairs of semicircular canals within the labyrinth are not perfectly aligned with the pulling directions of the six extraocular muscles. Therefore, for a given head movement, the vestibulo-ocular reflex (VOR) depends upon central neural mechanisms that couple the canals to the muscles with the appropriate functional gains in order to generate a response that rotates the eye the correct amount and around the correct axis. A consequence of these neural connections is a cross-axis adaptive capability, which can be stimulated experimentally when head rotation is around one axis and visual motion about another. From this visual-vestibular conflict the brain infers that the slow-phase eye movement is rotating around the wrong axis. We explored the capability of human cross-axis adaptation, using a short-term training paradigm, to determine if torsional eye movements could be elicited by yaw (horizontal) head rotation (where torsion is normally inappropriate). We applied yaw sinusoidal head rotation (+/-10 degrees, 0.33 Hz) and measured eye movement responses in the dark, and before and after adaptation. The adaptation paradigm lasted 45-60 min, and consisted of the identical head motion, coupled with a moving visual scene that required one of several types of eye movements: (1) torsion alone (-Roll); (2) horizontal/torsional, head right/CW torsion (Yaw-Roll); (3) horizontal/torsional, head right/CCW torsion (Yaw+Roll); (4) horizontal, vertical, torsional combined (Yaw+Pitch-Roll); and (5) horizontal and vertical together (Yaw+Pitch). The largest and most significant changes in torsional amplitude occurred in the Yaw-Roll and Yaw+Roll conditions. We conclude that short-term, cross-axis adaptation of torsion is possible but constrained by the complexity of the adaptation task: smaller torsional components are produced if more than one cross-coupling component is required. In contrast, vertical cross-axis components can be easily trained to occur with yaw head
DARHT Axis-I Diode Simulations II: Geometrical Scaling

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

Ekdahl, Carl A. Jr.

2012-06-14

Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. Many of the largest hydrodynamic experiments study mockups of nuclear weapons, and are often called hydrotests for short. The dual-axis radiography for hydrodynamic testing (DARHT) facility uses two electron linear-induction accelerators (LIA) to produce the radiographic source spots for perpendicular views of a hydrotest. The first of these LIAs produces a single pulse, with a fixed {approx}60-ns pulsewidth. The second axis LIA produces as many as four pulses within 1.6-{micro}s, with variable pulsewidths and separation. There are a wide varietymore » of hydrotest geometries, each with a unique radiographic requirement, so there is a need to adjust the radiographic dose for the best images. This can be accomplished on the second axis by simply adjusting the pulsewidths, but is more problematic on the first axis. Changing the beam energy or introducing radiation attenuation also changes the spectrum, which is undesirable. Moreover, using radiation attenuation introduces significant blur, increasing the effective spot size. The dose can also be adjusted by changing the beam kinetic energy. This is a very sensitive method, because the dose scales as the {approx}2.8 power of the energy, but it would require retuning the accelerator. This leaves manipulating the beam current as the best means for adjusting the dose, and one way to do this is to change the size of the cathode. This method has been proposed, and is being tested. This article describes simulations undertaken to develop scaling laws for use as design tools in changing the Axis-1 beam current by changing the cathode size.« less
Plasticity of the reproductive axis caused by social status change in an african cichlid fish: I. Pituitary gonadotropins.

PubMed

Maruska, Karen P; Levavi-Sivan, Berta; Biran, Jakob; Fernald, Russell D

2011-01-01

Social position in a dominance hierarchy is often tightly coupled with fertility. Consequently, an animal that can recognize and rapidly take advantage of an opportunity to rise in rank will have a reproductive advantage. Reproduction in all vertebrates is controlled by the brain-pituitary-gonad axis, and in males of the African cichlid fish Astatotilapia burtoni, GnRH1 neurons at the apex of this axis are under social control. However, little is known about how quickly social information is transformed into functional reproductive change, or about how socially controlled changes in GnRH1 neurons influence downstream actions of the brain-pituitary-gonad axis. We created an opportunity for reproductively suppressed males to ascend in status and then measured how quickly the perception of this opportunity caused changes in mRNA and protein levels of the pituitary gonadotropins. mRNA levels of the β-subunits of LH and FSH rose rapidly in the pituitary 30 min after suppressed males perceived an opportunity to ascend. In contrast, mRNA levels of GnRH receptor-1 remained unchanged during social transition but were higher in stable dominant compared with subordinate males. In the circulation, levels of both LH and FSH were also quickly elevated. There was a positive correlation between mRNA in the pituitary and circulating protein levels for LH and FSH, and both gonadotropins were positively correlated with plasma 11-ketotestosterone. Our results show that the pituitary is stimulated extremely rapidly after perception of social opportunity, probably to allow suppressed males to quickly achieve reproductive success in a dynamic social environment.
Asteroid (21) Lutetia: Semi-Automatic Impact Craters Detection and Classification

NASA Astrophysics Data System (ADS)

Jenerowicz, M.; Banaszkiewicz, M.

2018-05-01

The need to develop an automated method, independent of lighting and surface conditions, for the identification and measurement of impact craters, as well as the creation of a reliable and efficient tool, has become a justification of our studies. This paper presents a methodology for the detection of impact craters based on their spectral and spatial features. The analysis aims at evaluation of the algorithm capabilities to determinate the spatial parameters of impact craters presented in a time series. In this way, time-consuming visual interpretation of images would be reduced to the special cases. The developed algorithm is tested on a set of OSIRIS high resolution images of asteroid Lutetia surface which is characterized by varied landforms and the abundance of craters created by collisions with smaller bodies of the solar system.The proposed methodology consists of three main steps: characterisation of objects of interest on limited set of data, semi-automatic extraction of impact craters performed for total set of data by applying the Mathematical Morphology image processing (Serra, 1988, Soille, 2003), and finally, creating libraries of spatial and spectral parameters for extracted impact craters, i.e. the coordinates of the crater center, semi-major and semi-minor axis, shadow length and cross-section. The overall accuracy of the proposed method is 98 %, the Kappa coefficient is 0.84, the correlation coefficient is ∼ 0.80, the omission error 24.11 %, the commission error 3.45 %. The obtained results show that methods based on Mathematical Morphology operators are effective also with a limited number of data and low-contrast images.
Healthy and unhealthy dependence: implications for major depression.

PubMed

Schulte, Fiona S; Mongrain, Myriam; Flora, David B

2008-09-01

To examine the contribution of varying levels of dependency to Axis I and Axis II disorders, and to the recurrence of major depression in a graduate student sample diagnosed with a history of the disorder. At Time 1, participants were interviewed to confirm a current or past episode of major depression along with the presence of Axis II and other current or past Axis I disorders. Various measures of dependency were administered including the Depressive Experiences Questionnaire (DEQ; Blatt, D'Afflitti, & Quinlan, 1976), the 3-Vector Dependency Inventory (3VDI; Pincus & Gurtman, 1995), and the Personal Style Inventory (PSI; Robins et al., 1994). Participants were interviewed 20 months later to determine the recurrence of a depressive episode. A factor analysis conducted on scale scores for each dependency measure resulted in three factors labelled 'unhealthy', 'intermediate', and 'healthy' dependence. Controlling for history of major depression, structural equation modelling found 'unhealthy' dependence to be the only predictor of recurrences of major depression and Axis II disorders, while 'healthy' dependence was related to fewer depressive symptoms. These results have important implications for the conceptualization of the dependency construct.
Hydro-climatic Changes: Potential Non-linear Responses of Phosphorus Dynamic in Aquatic/Semi-aquatic Systems

NASA Astrophysics Data System (ADS)

Pant, H. K.

2007-12-01

Depending on resilience, threshold and lag times, hydro-climatic changes can cause nonlinear and/or irreversible changes in phosphorus (P) dynamic, and instigate P enrichment in aquatic/semi-aquatic systems. Thus, studying direct/indirect effects of expected global climate change on bioavailability of organic P in aquatic systems are in critical need, to help manage or increase the resilience of the ecosystem. The central hypothesis of this study is that P dynamic in aquatic, especially freshwater, ecosystem is likely to behave nonlinearly due to expected changes in sediment and water acidity, redox status, etc., because of potential hydro-climatic changes in the decades to come, thus, could face irreversible adverse changes. Devising possible biological and chemical treatments for the removal of P from eutrophic lakes, estuaries, etc, as well as helping in predicting the movement and fate of P under changing hydro-climatic conditions would be crucial to manage aquatic ecosystem in the near future. The critical question is not how much P is stored in any given aquatic/semi-aquatic system, but how the resilience and nonlinearity relate to the stability of stored P are affected due to the levels of environmental stressors, which are expected to fluctuate due to global change in the decades to come. Studies related to 31P Nuclear Magnetic Resonance Spectroscopy analysis, and multiple hydraulic retention cycles showed that, in general, frequent drying and reflooding of a semi-aquatic system such as wetland could significantly increase the bioavailability of P due to degradation of relatively less stable organic P, e.g., glycerophosphate and nucleoside monophosphate. Moreover, nutrients flux from sediments to the water column depended on the concentration gradients of the sediment-water interface and redox status. Shift in equilibrium P concentration of the water column as the water level rises, may cause release of adsorbed P from the sediments. Restoration of a

Predicting changes in hydrologic retention in an evolving semi-arid alluvial stream

USGS Publications Warehouse

Harvey, J.W.; Conklin, M.H.; Koelsch, R.S.

2003-01-01

Hydrologic retention of solutes in hyporheic zones or other slowly moving waters of natural channels is thought to be a significant control on biogeochemical cycling and ecology of streams. To learn more about factors affecting hydrologic retention, we repeated stream-tracer injections for 5 years in a semi-arid alluvial stream (Pinal Creek, Ariz.) during a period when streamflow was decreasing, channel width increasing, and coverage of aquatic macrophytes expanding. Average stream velocity at Pinal Creek decreased from 0.8 to 0.2 m/s, average stream depth decreased from 0.09 to 0.04 m, and average channel width expanded from 3 to 13 m. Modeling of tracer experiments indicated that the hydrologic retention factor (Rh), a measure of the average time that solute spends in storage per unit length of downstream transport, increased from 0.02 to 8 s/m. At the same time the ratio of cross-sectional area of storage zones to main channel cross-sectional area (As/A) increased from 0.2 to 0.8 m2/m2, and average water residence time in storage zones (ts) increased from 5 to 24 min. Compared with published data from four other streams in the US, Pinal Creek experienced the greatest change in hydrologic retention for a given change in streamflow. The other streams differed from Pinal Creek in that they experienced a change in streamflow between tracer experiments without substantial geomorphic or vegetative adjustments. As a result, a regression of hydrologic retention on streamflow developed for the other streams underpredicted the measured increases in hydrologic retention at Pinal Creek. The increase in hydrologic retention at Pinal Creek was more accurately predicted when measurements of the Darcy-Weisbach friction factor were used (either alone or in addition to streamflow) as a predictor variable. We conclude that relatively simple measurements of channel friction are useful for predicting the response of hydrologic retention in streams to major adjustments in channel
Does major depression result in lasting personality change?

PubMed

Shea, M T; Leon, A C; Mueller, T I; Solomon, D A; Warshaw, M G; Keller, M B

1996-11-01

Individuals with a history of depression are characterized by high levels of certain personality traits, particularly neuroticism, introversion, and interpersonal dependency. The authors examined the "scar hypothesis," i.e., the possibility that episodes of major depression result in lasting personality changes that persist beyond recovery from the depression. A large sample of first-degree relatives, spouses, and comparison subjects ascertained in connection with the proband sample from the National Institute of Mental Health Collaborative Program on the Psychobiology of Depression were assessed at two points in time separated by an interval of 6 years. Subjects with a prospectively observed first episode of major depression during the interval were compared with subjects remaining well in terms of change from time 1 to time 2 in self-reported personality traits. All subjects studied were well (had no mental disorders) at the time of both assessments. There was no evidence of negative change from premorbid to postmorbid assessment in any of the personality traits for subjects with a prospectively observed first episode of major depression during the interval. The results suggested a possible association of number and length of episodes with increased levels of emotional reliance and introversion, respectively. The findings suggest that self-reported personality traits do not change after a typical episode of major depression. Future studies are needed to determine whether such change occurs following more severe, chronic, or recurrent episodes of depression.
Semi-natural areas of Tarim Basin in northwest China: Linkage to desertification.

PubMed

Liu, Fang; Zhang, Hongqi; Qin, Yuanwei; Dong, Jinwei; Xu, Erqi; Yang, Yang; Zhang, Geli; Xiao, Xiangming

2016-12-15

Semi-natural lands are not intensively managed lands, which have ecological significance in protecting artificial oasis and preventing desertification in arid regions. The significant shrinkage and degradation of semi-natural lands in the land-use intensification process have caused severe desertification. However, there is a knowledge gap regarding the spatio-temporal pattern and detailed classification of semi-natural lands and its quantitative relationship with desertification. Taking the Tarim Basin as an example, we proposed a comprehensive classification system to identify semi-natural lands for 1990, 2000, and 2010, respectively, using multi-source datasets at large scales. Spatio-temporal changes of semi-natural lands were then characterized by map comparisons at decade intervals. Finally, statistical relationships between semi-natural lands and desertification were explored based on 241 watersheds. The area of semi-natural lands in Tarim Basin was 10.77×10 4 km 2 in 2010, and desert-vegetation type, native-oasis type, artificial-oasis type, saline type and wetland type accounted for 59.59%, 14.65%, 11.25%, 9.63% and 4.88% of the total area, respectively. A rapid loss of semi-natural lands (9769.05km 2 ) was demonstrated from 1990 to 2010. In the fragile watersheds, the semi-natural lands were mainly converted to desert; while in the watersheds with advanced oasis agriculture, artificial-oasis type reclaimed to arable land was the major change. The occurrence of desertification was closely related to the type, area proportion and combination patterns of semi-natural lands. Desertification was prone to occur in regions abundant in desert-vegetation type and saline type, while less serious desertification was observed in regions with high proportion of artificial-oasis type and wetland type. Policy intervention and reasonable water resource allocation were encouraged to prevent the substantial loss of semi-natural lands, especially for the water
A three-dimensional axis for the study of femoral neck orientation

PubMed Central

Bonneau, Noémie; Libourel, Paul-Antoine; Simonis, Caroline; Puymerail, Laurent; Baylac, Michel; Tardieu, Christine; Gagey, Olivier

2012-01-01

A common problem in the quantification of the orientation of the femoral neck is the difficulty to determine its true axis; however, this axis is typically estimated visually only. Moreover, the orientation of the femoral neck is commonly analysed using angles that are dependent on anatomical planes of reference and only quantify the orientation in two dimensions. The purpose of this study is to establish a method to determine the three-dimensional orientation of the femoral neck using a three-dimensional model. An accurate determination of the femoral neck axis requires a reconsideration of the complex architecture of the proximal femur. The morphology of the femoral neck results from both the medial and arcuate trabecular systems, and the asymmetry of the cortical bone. Given these considerations, two alternative models, in addition to the cylindrical one frequently assumed, were tested. The surface geometry of the femoral neck was subsequently used to fit one cylinder, two cylinders and successive cross-sectional ellipses. The model based on successive ellipses provided a significantly smaller average deviation than the two other models (P < 0.001) and reduced the observer-induced measurement error. Comparisons with traditional measurements and analyses on a sample of 91 femora were also performed to assess the validity of the model based on successive ellipses. This study provides a semi-automatic and accurate method for the determination of the functional three-dimensional femoral neck orientation avoiding the use of a reference plane. This innovative method has important implications for future studies that aim to document and understand the change in the orientation of the femoral neck associated with the acquisition of a bipedal gait in humans. Moreover, the precise determination of the three-dimensional orientation has implications in current research involved in developing clinical applications in diagnosis, hip surgery and rehabilitation. PMID:22967192
Pathological narcissism and narcissistic personality disorder in Axis I disorders.

PubMed

Ronningstam, E

1996-01-01

This paper presents available information on the comorbidity of narcissistic personality disorder (NPD) and pathological narcissism with major mental illness. A review of empirical studies reporting on the prevalence of NPD in Axis I disorders, and of theoretical and clinical literature on narcissistic pathology in major mental illness, forms the basis for an analysis of this interface. The results show that prevalence rates of NPD in Axis I disorders rarely exceed those found in the general psychiatric or personality disorder populations (i.e., less than 22%). NPD was found at high rates in individuals with a substance use disorder (12-38%) or bipolar disorder (4-47%); it was present at very low rates or absent in persons with obsessive-compulsive disorder. Higher prevalence rates were reported in the studies that used the Millon Clinical Multiaxial Inventory I or II than in those that employed the Structured interview for DSM-III Personality Disorders or the Structured Interview for DSM-III-R Personality Disorders--Revised. There is no evidence implicating a significant relationship between NPD and any specific Axis I disorder. A comparison of theoretical and clinical studies with empirical ones reveals major differences in the views regarding the presence and significance of NPD in Axis I disorders. However, the results highlight trends of interacting comorbidity between NPD and substance use disorders, bipolar disorder, depression, and anorexia nervosa.
Development of an integrated model of personality, personality disorders and severe axis I disorders, with special reference to major affective disorders.

PubMed

von Zerssen, Detlev

2002-04-01

A unidimensional model of the relationships between normal temperament, psychopathic variants of it and the two main forms of so-called endogenous psychoses (major affective disorders and schizophrenia) was derived from Kretschmer's constitutional typology. It was, however, not confirmed by means of a biometric approach nor was Kretschmer's broad concept of cyclothymia as a correlate of physical stoutness on the one hand and major affective disorders on the other supported by empirical data. Yet the concept of the 'melancholic type' of personality of patients with severe unipolar major depression (melancholia) which resembles descriptions by psychoanalysts could be corroborated. This was also true for the 'manic type' of personality as a (premorbid) correlate of predominantly manic forms of a bipolar I disorder. As predicted from a spectrum concept of major affective disorders, the ratio of traits of either type co-varied with the ratio of the depressive and the manic components in the long-term course of such a disorder. The two types of premorbid personality and a rare variant of the 'manic type', named 'relaxed, easy-going type', were conceived as 'affective types' dominating in major affective disorders. They are opposed to three 'neurotoid types' prevailing in so-called neurotic disorders as well as in schizophrenic psychoses. The similarity among the types can be visualized as spatial relationships in a circular, i.e. a two-dimensional, model (circumplex). Personality disorders as maladapted extreme variants of personality are, by definition, located outside the circle, mainly along its 'neurotoid' side. However, due to their transitional nature, axis I disorders cannot be represented adequately within the plane which represents (adapted as well as maladapted) forms of habitual behaviour (personality types and disorders, respectively). To integrate them into the spatial model of similarity interrelations, a dimension of actual psychopathology has to be added
Effects of land use/land cover and climate changes on surface runoff in a semi-humid and semi-arid transition zone in northwest China

NASA Astrophysics Data System (ADS)

Yin, Jing; He, Fan; Jiu Xiong, Yu; Qiu, Guo Yu

2017-01-01

Water resources, which are considerably affected by land use/land cover (LULC) and climate changes, are a key limiting factor in highly vulnerable ecosystems in arid and semi-arid regions. The impacts of LULC and climate changes on water resources must be assessed in these areas. However, conflicting results regarding the effects of LULC and climate changes on runoff have been reported in relatively large basins, such as the Jinghe River basin (JRB), which is a typical catchment (> 45 000 km2) located in a semi-humid and arid transition zone on the central Loess Plateau, northwest China. In this study, we focused on quantifying both the combined and isolated impacts of LULC and climate changes on surface runoff. We hypothesized that under climatic warming and drying conditions, LULC changes, which are primarily caused by intensive human activities such as the Grain for Green Program, will considerably alter runoff in the JRB. The Soil and Water Assessment Tool (SWAT) was adopted to perform simulations. The simulated results indicated that although runoff increased very little between the 1970s and the 2000s due to the combined effects of LULC and climate changes, LULC and climate changes affected surface runoff differently in each decade, e.g., runoff increased with increased precipitation between the 1970s and the 1980s (precipitation contributed to 88 % of the runoff increase). Thereafter, runoff decreased and was increasingly influenced by LULC changes, which contributed to 44 % of the runoff changes between the 1980s and 1990s and 71 % of the runoff changes between the 1990s and 2000s. Our findings revealed that large-scale LULC under the Grain for Green Program has had an important effect on the hydrological cycle since the late 1990s. Additionally, the conflicting findings regarding the effects of LULC and climate changes on runoff in relatively large basins are likely caused by uncertainties in hydrological simulations.
Behavioural response in subterranean and semi-aquatic invertebrates following experimental simulation of pre-seismic changes

NASA Astrophysics Data System (ADS)

Conlan, Hilary; Grant, Rachel

2013-04-01

When tectonic stresses build up in the Earth's crust, highly mobile electronic charge carriers are activated which cause a range of follow-on reactions when they arrive at the Earth's surface, primarily air ionization and at the rock-water interface oxidation of water to hydrogen peroxide. Anecdotal reports of many earthworms appearing at the ground surface and behavioural changes in toads before earthquakes suggests that these animals may be reacting to environmental changes. This paper reports the results of experimental work, with subterranean and semi-aquatic invertebrates, simulating these pre-earthquake changes.
Dual axis operation of a micromachined rate gyroscope

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

Juneau, T.; Pisano, A.P.; Smith, J.

Since micromachining technology has raised the prospect of fabricating high performance sensors without the associated high cost and large size, many researchers have investigated micromachined rate gyroscopes. The vast majority of research has focused on single input axis rate gyroscopes, but this paper presents work on a dual input axis micromachined rate gyroscope. The key to successful simultaneous dual axis operation is the quad symmetry of the circular oscillating rotor design. Untuned gyroscopes with mismatched modes yielded random walk as low as 10{degrees}/{radical}hour with cross sensitivity ranging from 6% to 16%. Mode frequency matching via electrostatic tuning allowed performance bettermore » than 2{degrees}/{radical}hour, but at the expense of excessive cross sensitivity.« less
Major transcriptome re-organisation and abrupt changes in signalling, cell cycle and chromatin regulation at neural differentiation in vivo.

PubMed

Olivera-Martinez, Isabel; Schurch, Nick; Li, Roman A; Song, Junfang; Halley, Pamela A; Das, Raman M; Burt, Dave W; Barton, Geoffrey J; Storey, Kate G

2014-08-01

Here, we exploit the spatial separation of temporal events of neural differentiation in the elongating chick body axis to provide the first analysis of transcriptome change in progressively more differentiated neural cell populations in vivo. Microarray data, validated against direct RNA sequencing, identified: (1) a gene cohort characteristic of the multi-potent stem zone epiblast, which contains neuro-mesodermal progenitors that progressively generate the spinal cord; (2) a major transcriptome re-organisation as cells then adopt a neural fate; and (3) increasing diversity as neural patterning and neuron production begin. Focussing on the transition from multi-potent to neural state cells, we capture changes in major signalling pathways, uncover novel Wnt and Notch signalling dynamics, and implicate new pathways (mevalonate pathway/steroid biogenesis and TGFβ). This analysis further predicts changes in cellular processes, cell cycle, RNA-processing and protein turnover as cells acquire neural fate. We show that these changes are conserved across species and provide biological evidence for reduced proteasome efficiency and a novel lengthening of S phase. This latter step may provide time for epigenetic events to mediate large-scale transcriptome re-organisation; consistent with this, we uncover simultaneous downregulation of major chromatin modifiers as the neural programme is established. We further demonstrate that transcription of one such gene, HDAC1, is dependent on FGF signalling, making a novel link between signals that control neural differentiation and transcription of a core regulator of chromatin organisation. Our work implicates new signalling pathways and dynamics, cellular processes and epigenetic modifiers in neural differentiation in vivo, identifying multiple new potential cellular and molecular mechanisms that direct differentiation. © 2014. Published by The Company of Biologists Ltd.
Stress Biomarkers, Mood States, and Sleep during a Major Competition: “Success” and “Failure” Athlete's Profile of High-Level Swimmers

PubMed Central

Chennaoui, Mounir; Bougard, Clément; Drogou, Catherine; Langrume, Christophe; Miller, Christian; Gomez-Merino, Danielle; Vergnoux, Frédéric

2016-01-01

The aim of this study was to evaluate stress markers, mood states, and sleep indicators in high-level swimmers during a major 7-days competition according to the outcomes. Nine swimmers [six men and three women (age: 22 ± 2 and 22 ± 4 years, respectively)] were examined. Before (PRE) and after (POST) each race (series, semi-finals, and finals), salivary concentrations of cortisol, α-amylase (sAA), and chromogranin-A (CgA) were determined. Mood states were assessed by the profile of mood state (POMS) questionnaire completed before and after the 7-days, and self-reported sleep diaries were completed daily. In the “failure” group, cortisol and sAA significantly increased between PRE-POST measurements (p < 0.05), while sCgA was not changed. Significant overall decrease of cortisol (-52.6%) and increase of sAA (+68.7%) was shown in the “failure group.” In this group, fatigue, confusion and depression scores, and sleep duration before the finals increased. The results in the “success” group show tendencies for increased cortisol and sCgA concentrations in response to competition, while sAA was not changed. Cortisol levels before the semi-finals and finals and sCgA levels before the finals were positively correlated to the fatigue score in the “failure” group only (r = 0.89). sAA levels before and after the semi-finals were negatively correlated to sleep duration measured in the subsequent night (r = −0.90). In conclusion, the stress of the competition could trigger a negative mood profile and sleep disturbance which correspond to different responses of biomarkers related to the hypothalamo-pituitary-adrenal axis and the sympathetic nervous system (SNS) activity, cortisol, sAA, and CgA. PMID:27014092
20 CFR 418.1205 - What is a major life-changing event?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What is a major life-changing event? 418.1205... Gross Income § 418.1205 What is a major life-changing event? For the purposes of this subpart, we will consider the following to be major life-changing events: (a) Your spouse dies; (b) You marry; (c) Your...
20 CFR 418.1205 - What is a major life-changing event?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What is a major life-changing event? 418.1205... Gross Income § 418.1205 What is a major life-changing event? For the purposes of this subpart, we will consider the following to be major life-changing events: (a) Your spouse dies; (b) You marry; (c) Your...
20 CFR 418.1205 - What is a major life-changing event?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false What is a major life-changing event? 418.1205... Gross Income § 418.1205 What is a major life-changing event? For the purposes of this subpart, we will consider the following to be major life-changing events: (a) Your spouse dies; (b) You marry; (c) Your...
Vergence-mediated changes in the axis of eye rotation during the human vestibulo-ocular reflex can occur independent of eye position.

PubMed

Migliaccio, Americo A; Cremer, Phillip D; Aw, Swee T; Halmagyi, G Michael; Curthoys, Ian S; Minor, Lloyd B; Todd, Michael J

2003-07-01

The aim of this study was to determine whether vergence-mediated changes in the axis of eye rotation in the human vestibulo-ocular reflex (VOR) would obey Listing's Law (normally associated with saccadic eye movements) independent of the initial eye position. We devised a paradigm for disassociating the saccadic velocity axis from eye position by presenting near and far targets that were centered with respect to one eye. We measured binocular 3-dimensional eye movements using search coils in ten normal subjects and 3-dimensional linear head acceleration using Optotrak in seven normal subjects. The stimuli consisted of passive, unpredictable, pitch head rotations with peak acceleration of approximately 2000 degrees /s(2 )and amplitude of approximately 20 degrees. During the pitch head rotation, each subject fixated straight ahead with one eye, whereas the other eye was adducted 4 degrees during far viewing (94 cm) and 25 degrees during near viewing (15 cm). Our data showed expected compensatory pitch rotations in both eyes, and a vergence-mediated horizontal rotation only in the adducting eye. In addition, during near viewing we observed torsional eye rotations not only in the adducting eye but also in the eye looking straight ahead. In the straight-ahead eye, the change in torsional eye velocity between near and far viewing, which began approximately 40 ms after the start of head rotation, was 10+/-6 degrees /s (mean +/- SD). This change in torsional eye velocity resulted in a 2.4+/-1.5 degrees axis tilt toward Listing's plane in that eye. In the adducting eye, the change in torsional eye velocity between near and far viewing was 16+/-6 degrees /s (mean +/- SD) and resulted in a 4.1+/-1.4 degrees axis tilt. The torsional eye velocities were conjugate and both eyes partially obeyed Listing's Law. The axis of eye rotation tilted in the direction of the line of sight by approximately one-third of the angle between the line of sight and a line orthogonal to Listing
English Language Learners' Perceptions of Motivational Changes

ERIC Educational Resources Information Center

Lai, Hsuan-Yau Tony; Ting, Kuang-yun

2013-01-01

This study explores the changes in Taiwanese university students' English-learning motivation and the causes of these changes. The emphasis herein is on a comparison and contrast of both English major and non-major students in three different universities in Taiwan. In the study, a qualitative approach (20 semi-structured interviews) was used. The…
Anisotropic structural and optical properties of semi-polar (11-22) GaN grown on m-plane sapphire using double AlN buffer layers.

PubMed

Zhao, Guijuan; Wang, Lianshan; Yang, Shaoyan; Li, Huijie; Wei, Hongyuan; Han, Dongyue; Wang, Zhanguo

2016-02-10

We report the anisotropic structural and optical properties of semi-polar (11-22) GaN grown on m-plane sapphire using a three-step growth method which consisted of a low temperature AlN buffer layer, followed by a high temperature AlN buffer layer and GaN growth. By introducing double AlN buffer layers, we substantially improve the crystal and optical qualities of semi-polar (11-22) GaN, and significantly reduce the density of stacking faults and dislocations. The high resolution x-ray diffraction measurement revealed that the in-plane anisotropic structural characteristics of GaN layer are azimuthal dependent. Transmission electron microscopy analysis showed that the majority of dislocations in the GaN epitaxial layer grown on m-sapphire are the mixed-type and the orientation of GaN layer was rotated 58.4° against the substrate. The room temperature photoluminescence (PL) spectra showed the PL intensity and wavelength have polarization dependence along parallel and perpendicular to the [1-100] axis (polarization degrees ~ 0.63). The realization of a high polarization semi-polar GaN would be useful to achieve III-nitride based lighting emission device for displays and backlighting.
Predicting the Affects of Climate Change on Evapotranspiration and Agricultural Productivity of Semi-arid Basins

NASA Astrophysics Data System (ADS)

Peri, L.; Tyler, S. W.; Zheng, C.; Pohll, G. M.; Yao, Y.

2013-12-01

Many arid and semi-arid regions around the world are experiencing water shortages that have become increasingly problematic. Since the late 1800s, upstream diversions in Nevada's Walker River have delivered irrigation supply to the surrounding agricultural fields resulting in a dramatic water level decline of the terminal Walker Lake. Salinity has also increased because the only outflow from the lake is evaporation from the lake surface. The Heihe River basin of northwestern China, a similar semi-arid catchment, is also facing losses from evaporation of terminal locations, agricultural diversions and evapotranspiration (ET) of crops. Irrigated agriculture is now experiencing increased competition for use of diminishing water resources while a demand for ecological conservation continues to grow. It is important to understand how the existing agriculture in these regions will respond as climate changes. Predicting the affects of climate change on groundwater flow, surface water flow, ET and agricultural productivity of the Walker and Heihe River basins is essential for future conservation of water resources. ET estimates from remote sensing techniques can provide estimates of crop water consumption. By determining similarities of both hydrologic cycles, critical components missing in both systems can be determined and predictions of impacts of climate change and human management strategies can be assessed.
Three axis velocity probe system

DOEpatents

Fasching, George E.; Smith, Jr., Nelson S.; Utt, Carroll E.

1992-01-01

A three-axis velocity probe system for determining three-axis positional velocities of small particles in fluidized bed systems and similar applications. This system has a sensor head containing four closely-spaced sensing electrodes of small wires that have flat ends to establish a two axis plane, e.g. a X-Y plane. Two of the sensing electrodes are positioned along one of the axes and the other two are along the second axis. These four sensing electrodes are surrounded by a guard electrode, and the outer surface is a ground electrode and support member for the sensing head. The electrodes are excited by, for example, sinusoidal voltage having a peak-to-peak voltage of up to 500 volts at a frequency of 2 MHz. Capacitive currents flowing between the four sensing electrodes and the ground electrode are influenced by the presence and position of a particle passing the sensing head. Any changes in these currents due to the particle are amplified and synchronously detected to produce positional signal values that are converted to digital form. Using these digital forms and two values of time permit generation of values of the three components of the particle vector and thus the total velocity vector.
Multiphase Interface Tracking with Fast Semi-Lagrangian Contouring.

PubMed

Li, Xiaosheng; He, Xiaowei; Liu, Xuehui; Zhang, Jian J; Liu, Baoquan; Wu, Enhua

2016-08-01

We propose a semi-Lagrangian method for multiphase interface tracking. In contrast to previous methods, our method maintains an explicit polygonal mesh, which is reconstructed from an unsigned distance function and an indicator function, to track the interface of arbitrary number of phases. The surface mesh is reconstructed at each step using an efficient multiphase polygonization procedure with precomputed stencils while the distance and indicator function are updated with an accurate semi-Lagrangian path tracing from the meshes of the last step. Furthermore, we provide an adaptive data structure, multiphase distance tree, to accelerate the updating of both the distance function and the indicator function. In addition, the adaptive structure also enables us to contour the distance tree accurately with simple bisection techniques. The major advantage of our method is that it can easily handle topological changes without ambiguities and preserve both the sharp features and the volume well. We will evaluate its efficiency, accuracy and robustness in the results part with several examples.

Influence of Moisture Content and Compression Axis on Physico-mechanical Properties of Shorea robusta Seeds

NASA Astrophysics Data System (ADS)

Shashikumar, C.; Pradhan, R. C.; Mishra, S.

2018-06-01

Shorea robusta (Sal) is mainly harvested and processed for its seed oil, which has diverse application in commercial food and non-food based industries. Before extraction of its oil, seeds undergo into various post-harvest unit operations. Physical and mechanical properties play an important role in the handling and other processing activity. In this study influence of moisture content and compression axis of sal seed on physico-mechanical properties were studied and their application are highlighted. The experiments were conducted at five different moisture levels of 6.38, 10.49, 13.63, 17.64, and 21.95% (d.b) at two different orientations. The first orientation is on major axis (LEN) of the seed, and the other orientation is on intermediate or minor axis (WID), which is right angle to the major axis. It was observed that 68% of sal seeds were of medium size group at initial moisture content of 10.49% (d.b). The mean length and width of sal seed was found to be 26.7 mm and 12.8 mm, respectively. It was found that values of hardness, deformation at hardness, deformation at hardness percentage and energy for rupture were higher in minor axis (WID) as compared to the major axis (LEN). The results provide necessary data that may be useful to engineers, scientists, industries in the design of a suitable post-harvest processing machine.
Influence of Moisture Content and Compression Axis on Physico-mechanical Properties of Shorea robusta Seeds

NASA Astrophysics Data System (ADS)

Shashikumar, C.; Pradhan, R. C.; Mishra, S.

2018-02-01

Shorea robusta (Sal) is mainly harvested and processed for its seed oil, which has diverse application in commercial food and non-food based industries. Before extraction of its oil, seeds undergo into various post-harvest unit operations. Physical and mechanical properties play an important role in the handling and other processing activity. In this study influence of moisture content and compression axis of sal seed on physico-mechanical properties were studied and their application are highlighted. The experiments were conducted at five different moisture levels of 6.38, 10.49, 13.63, 17.64, and 21.95% (d.b) at two different orientations. The first orientation is on major axis (LEN) of the seed, and the other orientation is on intermediate or minor axis (WID), which is right angle to the major axis. It was observed that 68% of sal seeds were of medium size group at initial moisture content of 10.49% (d.b). The mean length and width of sal seed was found to be 26.7 mm and 12.8 mm, respectively. It was found that values of hardness, deformation at hardness, deformation at hardness percentage and energy for rupture were higher in minor axis (WID) as compared to the major axis (LEN). The results provide necessary data that may be useful to engineers, scientists, industries in the design of a suitable post-harvest processing machine.
Probiotics normalize the gut-brain-microbiota axis in immunodeficient mice

PubMed Central

Smith, Carli J.; Emge, Jacob R.; Berzins, Katrina; Lung, Lydia; Khamishon, Rebecca; Shah, Paarth; Rodrigues, David M.; Sousa, Andrew J.; Reardon, Colin; Sherman, Philip M.; Barrett, Kim E.

2014-01-01

The gut-brain-microbiota axis is increasingly recognized as an important regulator of intestinal physiology. Exposure to psychological stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis and causes altered intestinal barrier function, intestinal dysbiosis, and behavioral changes. The primary aim of this study was to determine whether the effects of psychological stress on intestinal physiology and behavior, including anxiety and memory, are mediated by the adaptive immune system. Furthermore, we wanted to determine whether treatment with probiotics would normalize these effects. Here we demonstrate that B and T cell-deficient Rag1−/− mice displayed altered baseline behaviors, including memory and anxiety, accompanied by an overactive HPA axis, increased intestinal secretory state, dysbiosis, and decreased hippocampal c-Fos expression. Both local (intestinal physiology and microbiota) and central (behavioral and hippocampal c-Fos) changes were normalized by pretreatment with probiotics, indicating an overall benefit on health conferred by changes in the microbiota, independent of lymphocytes. Taken together, these findings indicate a role for adaptive immune cells in maintaining normal intestinal and brain health in mice and show that probiotics can overcome this immune-mediated deficit in the gut-brain-microbiota axis. PMID:25190473
Probiotics normalize the gut-brain-microbiota axis in immunodeficient mice.

PubMed

Smith, Carli J; Emge, Jacob R; Berzins, Katrina; Lung, Lydia; Khamishon, Rebecca; Shah, Paarth; Rodrigues, David M; Sousa, Andrew J; Reardon, Colin; Sherman, Philip M; Barrett, Kim E; Gareau, Mélanie G

2014-10-15

The gut-brain-microbiota axis is increasingly recognized as an important regulator of intestinal physiology. Exposure to psychological stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis and causes altered intestinal barrier function, intestinal dysbiosis, and behavioral changes. The primary aim of this study was to determine whether the effects of psychological stress on intestinal physiology and behavior, including anxiety and memory, are mediated by the adaptive immune system. Furthermore, we wanted to determine whether treatment with probiotics would normalize these effects. Here we demonstrate that B and T cell-deficient Rag1(-/-) mice displayed altered baseline behaviors, including memory and anxiety, accompanied by an overactive HPA axis, increased intestinal secretory state, dysbiosis, and decreased hippocampal c-Fos expression. Both local (intestinal physiology and microbiota) and central (behavioral and hippocampal c-Fos) changes were normalized by pretreatment with probiotics, indicating an overall benefit on health conferred by changes in the microbiota, independent of lymphocytes. Taken together, these findings indicate a role for adaptive immune cells in maintaining normal intestinal and brain health in mice and show that probiotics can overcome this immune-mediated deficit in the gut-brain-microbiota axis. Copyright © 2014 the American Physiological Society.
Assessment of climate change impact on yield of major crops in the Banas River Basin, India.

PubMed

Dubey, Swatantra Kumar; Sharma, Devesh

2018-09-01

Crop growth models like AquaCrop are useful in understanding the impact of climate change on crop production considering the various projections from global circulation models and regional climate models. The present study aims to assess the climate change impact on yield of major crops in the Banas River Basin i.e., wheat, barley and maize. Banas basin is part of the semi-arid region of Rajasthan state in India. AquaCrop model is used to calculate the yield of all the three crops for a historical period of 30years (1981-2010) and then compared with observed yield data. Root Mean Square Error (RMSE) values are calculated to assess the model accuracy in prediction of yield. Further, the calibrated model is used to predict the possible impacts of climate change and CO 2 concentration on crop yield using CORDEX-SA climate projections of three driving climate models (CNRM-CM5, CCSM4 and MPI-ESM-LR) for two different scenarios (RCP4.5 and RCP8.5) for the future period 2021-2050. RMSE values of simulated yield with respect to observed yield of wheat, barley and maize are 11.99, 16.15 and 19.13, respectively. It is predicted that crop yield of all three crops will increase under the climate change conditions for future period (2021-2050). Copyright © 2018 Elsevier B.V. All rights reserved.
A Framework Predicting Water Availability in a Rapidly Growing, Semi-Arid Region under Future Climate Change

NASA Astrophysics Data System (ADS)

Han, B.; Benner, S. G.; Glenn, N. F.; Lindquist, E.; Dahal, K. R.; Bolte, J.; Vache, K. B.; Flores, A. N.

2014-12-01

Climate change can lead to dramatic variations in hydrologic regime, affecting both surface water and groundwater supply. This effect is most significant in populated semi-arid regions where water availability are highly sensitive to climate-induced outcomes. However, predicting water availability at regional scales, while resolving some of the key internal variability and structure in semi-arid regions is difficult due to the highly non-linearity relationship between rainfall and runoff. In this study, we describe the development of a modeling framework to evaluate future water availability that captures elements of the coupled response of the biophysical system to climate change and human systems. The framework is built under the Envision multi-agent simulation tool, characterizing the spatial patterns of water demand in the semi-arid Treasure Valley area of Southwest Idaho - a rapidly developing socio-ecological system where urban growth is displacing agricultural production. The semi-conceptual HBV model, a population growth and allocation model (Target), a vegetation state and transition model (SSTM), and a statistically based fire disturbance model (SpatialAllocator) are integrated to simulate hydrology, population and land use. Six alternative scenarios are composed by combining two climate change scenarios (RCP4.5 and RCP8.5) with three population growth and allocation scenarios (Status Quo, Managed Growth, and Unconstrained Growth). Five-year calibration and validation performances are assessed with Nash-Sutcliffe efficiency. Irrigation activities are simulated using local water rights. Results show that in all scenarios, annual mean stream flow decreases as the projected rainfall increases because the projected warmer climate also enhances water losses to evapotranspiration. Seasonal maximum stream flow tends to occur earlier than in current conditions due to the earlier peak of snow melting. The aridity index and water deficit generally increase in the
14 CFR 380.33 - Major changes in itinerary or price; refunds.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Major changes in itinerary or price... § 380.33 Major changes in itinerary or price; refunds. (a) For the purposes of this section, “major...; and (4) A price increase to the participant that occurs 10 or more days before departure and results...
Night Eating Syndrome in Major Depression and Anxiety Disorders.

PubMed

Küçükgöncü, Suat; Beştepe, Emrem

2014-12-01

The purpose of this study is to investigate the prevalence and the clinical features of night eating syndrome (NES) in patients with depression and anxiety disorders. The study was conducted at Bakırköy State Hospital for Mental Health and Neurological Disorders. Three-hundred out-patients who had major depression (MD), panic disorders (PD), general anxiety disorders (GAD) and obsessive-compulsive disorders (OCD) participated in the study. The semi-structured socio-demographic form, the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Night Eating Questionnaire, and NES Evaluation Questionnaire were implemented. In our sample, the prevalence of the NES was 15.7% (n=47). NES frequency was significantly higher in the patients diagnosed with major depression (MD 22%, GAD 7.8%, OCD 12.5%, PD 14%). Smoking, presence of past suicide attempts, rates of antipsychotic drugs use, and average scores of body mass index (BMI) were significantly higher in the patients who had NES. In this sample, depression, BMI, and smoking were found to be determinants of NES. This study shows that NES may be frequently observed in patients admitted to psychiatric clinics, especially in those with major depression. Evaluation of NES in psychiatric patients may help the treatment of the primary psychopathology and prevent the adverse effects, like weight gain, which may reduce the quality of life.
20 CFR 418.1210 - What is not a major life-changing event?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What is not a major life-changing event? 418... Adjusted Gross Income § 418.1210 What is not a major life-changing event? We will not consider events other than those described in § 418.1205 to be major life-changing events. Certain types of events are not...
20 CFR 418.1210 - What is not a major life-changing event?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What is not a major life-changing event? 418... Adjusted Gross Income § 418.1210 What is not a major life-changing event? We will not consider events other than those described in § 418.1205 to be major life-changing events. Certain types of events are not...
Effect of low NH3 flux towards high quality semi-polar (11-22) GaN on m-plane sapphire via MOCVD

NASA Astrophysics Data System (ADS)

Omar, Al-Zuhairi; Shuhaimi Bin Abu Bakar, Ahmad; Makinudin, Abdullah Haaziq Ahmad; Khudus, Muhammad Imran Mustafa Abdul; Azman, Adreen; Kamarundzaman, Anas; Supangat, Azzuliani

2018-05-01

The effect of ammonia flux towards the quality of the semi-polar (11-22) gallium nitride thin film on m-plane (10-10) sapphire is presented. Semi-polar (11-22) gallium nitride epi-layers were obtained using a two-step growth method, consisting of high temperature aluminum nitride followed by gallium nitride via metal organic chemical vapor deposition. The surface morphology analysis via field emission scanning electron microscopy and atomic force microscopy of the semi-polar (11-22) gallium nitride has shown that low ammonia flux promotes two-dimensional growth with low surface roughness of 4.08 nm. A dominant diffraction peak of (11-22) gallium nitride was also observed via X-ray diffraction upon utilizing low ammonia flux. The on- and off-axis X-ray rocking curve measurements illustrate the enhancement of the crystal quality, which might result from the reduction of the basal stacking faults and perfect dislocation. The full width half maximum values were reduced by at least 15% for both on- and off-axis measurements.
The G-Axis: a growth vector for the mandible.

PubMed

Braun, Stanley; Kittleson, Russell; Kim, Kyonghwan

2004-06-01

On the basis of the G-point, defined as the center of the largest circle that is tangent to the internal inferior, anterior, and lingual surfaces of the mandibular symphysis in the sagittal view, a growth axis and its direction are described for each gender from age six to 19.25 years. Incremental growth along the G-Axis, defined by Sella-G-point, is described by regression formulas with correlation coefficients of 0.673 for female subjects and 0.749 for male subjects. The vector (direction) of the growth axis, defined by the angle alpha ((G-Axis)-(S-N)) does not materially alter in the age range studied. At age six in female subjects the angle alpha is 67.16 degrees +/- 3.03 degrees and at age 19.25 it is 66.87 degrees +/- 3.03 degrees, whereas in male subjects it is 66.12 degrees +/- 4.00 degrees and 67.93 degrees +/- 4.00 degrees, respectively. These changes and gender differences are not clinically significant. The data is based on 444 serial lateral cephalograms of 24 female subjects and 24 male subjects. The G-Axis incremental growth change and its vector offer an improved means of quantifying complex mandibular growth in the sagittal plane by using cephalometric measurements relative to and correlated with other craniofacial structures.
Influence of temperature on the optical system with large diameter off-axis parabolic lenses

NASA Astrophysics Data System (ADS)

Su, Yaru; Ruan, Hao; Liu, Jie

2016-10-01

In this work, an optical system with large diameter off-axis parabolic lenses was adopted to achieve diffraction gratings by laser interference exposure. The diffraction wavefront aberration caused by temperature variations was simulated using ZEMAX. Through theoretical analysis and optical simulation, it is proved that the diffraction wavefront aberration of holographic grating caused by the pinhole's location errors (it is assumed that when the displacement of pinhole exists along one axis, the locations of the pinhole along the other two orthogonal axes are in a state of precise adjustment ) is much larger when the displacement occurs along z axis than along the other two axes, and the diffraction wavefront aberration is the smallest when the displacement occurs along x axis. If the ambient temperature changes by 1 degree, the PV value is 0.0631λ when the location of the pinhole changes by 0.121mm along z axis, 0.0034λor 0.0672λ when the location of the pinhole changes by 0.002mm along x axis or 0.03mm along y axis. To reach the diffraction limit (that means the PV value is 0.25λ), the decentering value of the pinhole along z axis should be less than 0.0341mm. In conclusion, the position error along z axis is an important factor to influence the PV value of diffraction grating, and the effect of temperature on the PV value of diffraction grating can be neglected.
Personality and symptom change in treatment-refractory inpatients: evaluation of the phase model of change using Rorschach,TAT, and DSM-IV Axis V.

PubMed

Fowler, J Christopher; Ackerman, Steven J; Speanburg, Stefanie; Bailey, Adrian; Blagys, Matthew; Conklin, Adam C

2004-12-01

In this study, we examined global treatment outcomes during 16 months of intensive, psychodynamic treatment for 77 inpatients suffering from treatment-refractory disorders. Hypotheses based on the phase model of treatment change (Howard, Lueger, Maling, & Martinovich, 1993; Howard, Moras, Brill, Martinovich, & Lutz, 1996) were supported in the study results. Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) Axis V scales assessing behavioral functioning demonstrated large and medium effect size change, whereas stable, enduring personality functioning assessed by psychoanalytic Rorschach scales and the Social Cognition and Object Relations Scale (Westen, 1995) for the Thematic Apperception Test (Murray, 1943) demonstrated small and medium effect size change. We also report assessment of reliable change index and clinical significance. The ecological validity of Rorschach measures is supported by significant validity coefficients (in the hypothesized directions) between implicit measures of personality functioning and behavioral ratings.
The alignment between phenotypic plasticity, the major axis of genetic variation and the response to selection.

PubMed

Lind, Martin I; Yarlett, Kylie; Reger, Julia; Carter, Mauricio J; Beckerman, Andrew P

2015-10-07

Phenotypic plasticity is the ability of a genotype to produce more than one phenotype in order to match the environment. Recent theory proposes that the major axis of genetic variation in a phenotypically plastic population can align with the direction of selection. Therefore, theory predicts that plasticity directly aids adaptation by increasing genetic variation in the direction favoured by selection and reflected in plasticity. We evaluated this theory in the freshwater crustacean Daphnia pulex, facing predation risk from two contrasting size-selective predators. We estimated plasticity in several life-history traits, the G matrix of these traits, the selection gradients on reproduction and survival, and the predicted responses to selection. Using these data, we tested whether the genetic lines of least resistance and the predicted response to selection aligned with plasticity. We found predator environment-specific G matrices, but shared genetic architecture across environments resulted in more constraint in the G matrix than in the plasticity of the traits, sometimes preventing alignment of the two. However, as the importance of survival selection increased, the difference between environments in their predicted response to selection increased and resulted in closer alignment between the plasticity and the predicted selection response. Therefore, plasticity may indeed aid adaptation to new environments. © 2015 The Authors.
Characterization of the Hypothalamic-Pituitary-Adrenal-Axis in Familial Longevity under Resting Conditions.

PubMed

Jansen, Steffy W; Roelfsema, Ferdinand; Akintola, Abimbola A; Oei, Nicole Y; Cobbaert, Christa M; Ballieux, Bart E; van der Grond, Jeroen; Westendorp, Rudi G; Pijl, Hanno; van Heemst, Diana

2015-01-01

The hypothalamic-pituitary-adrenal (HPA)-axis is the most important neuro-endocrine stress response system of our body which is of critical importance for survival. Disturbances in HPA-axis activity have been associated with adverse metabolic and cognitive changes. Humans enriched for longevity have less metabolic and cognitive disturbances and therefore diminished activity of the HPA axis may be a potential candidate mechanism underlying healthy familial longevity. Here, we compared 24-h plasma ACTH and serum cortisol concentration profiles and different aspects of the regulation of the HPA-axis in offspring from long-lived siblings, who are enriched for familial longevity and age-matched controls. Case-control study within the Leiden Longevity study cohort consisting of 20 middle-aged offspring of nonagenarian siblings (offspring) together with 18 partners (controls). During 24 h, venous blood was sampled every 10 minutes for determination of circulatory ACTH and cortisol concentrations. Deconvolution analysis, cross approximate entropy analysis and ACTH-cortisol-dose response modeling were used to assess, respectively, ACTH and cortisol secretion parameters, feedforward and feedback synchrony and adrenal gland ACTH responsivity. Mean (95% Confidence Interval) basal ACTH secretion was higher in male offspring compared to male controls (645 (324-1286) ngl/L/24 h versus 240 (120-477) ng/L/24 h, P = 0.05). Other ACTH and cortisol secretion parameters did not differ between offspring and controls. In addition, no significant differences in feedforward and feedback synchrony and adrenal gland ACTH responsivity were observed between groups. These results suggest that familial longevity is not associated with major differences in HPA-axis activity under resting conditions, although modest, sex-specific differences may exist between groups that might be clinically relevant.
Testing for post-copulatory selection for major histocompatibility complex genotype in a semi-free-ranging primate population.

PubMed

Setchell, Joanna M; Abbott, Kristin M; Gonzalez, Jean-Paul; Knapp, Leslie A

2013-10-01

A large body of evidence suggests that major histocompatibility complex (MHC) genotype influences mate choice. However, few studies have investigated MHC-mediated post-copulatory mate choice under natural, or even semi-natural, conditions. We set out to explore this question in a large semi-free-ranging population of mandrills (Mandrillus sphinx) using MHC-DRB genotypes for 127 parent-offspring triads. First, we showed that offspring MHC heterozygosity correlates positively with parental MHC dissimilarity suggesting that mating among MHC dissimilar mates is efficient in increasing offspring MHC diversity. Second, we compared the haplotypes of the parental dyad with those of the offspring to test whether post-copulatory sexual selection favored offspring with two different MHC haplotypes, more diverse gamete combinations, or greater within-haplotype diversity. Limited statistical power meant that we could only detect medium or large effect sizes. Nevertheless, we found no evidence for selection for heterozygous offspring when parents share a haplotype (large effect size), genetic dissimilarity between parental haplotypes (we could detect an odds ratio of ≥1.86), or within-haplotype diversity (medium-large effect). These findings suggest that comparing parental and offspring haplotypes may be a useful approach to test for post-copulatory selection when matings cannot be observed, as is the case in many study systems. However, it will be extremely difficult to determine conclusively whether post-copulatory selection mechanisms for MHC genotype exist, particularly if the effect sizes are small, due to the difficulty in obtaining a sufficiently large sample. © 2013 Wiley Periodicals, Inc.
Nutrient restriction induces failure of reproductive function and molecular changes in hypothalamus-pituitary-gonadal axis in postpubertal gilts.

PubMed

Zhou, Dongsheng; Zhuo, Yong; Che, Lianqiang; Lin, Yan; Fang, Zhengfeng; Wu, De

2014-07-01

People on a diet to lose weight may be at risk of reproductive failure. To investigate the effects of nutrient restriction on reproductive function and the underlying mechanism, changes of reproductive traits, hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis were examined in postpubertal gilts at anestrus induced by nutrient restriction. Gilts having experienced two estrus cycles were fed a normal (CON, 2.86 kg/d) or nutrient restricted (NR, 1 kg/d) food regimens to expect anestrus. NR gilts experienced another three estrus cycles, but did not express estrus symptoms at the anticipated fourth estrus. Blood samples were collected at 5 days' interval for consecutive three times for measurement of hormone concentrations at the 23th day of the fourth estrus cycle. Individual progesterone concentrations of NR gilts from three consecutive blood samples were below 1.0 ng/mL versus 2.0 ng/mL in CON gilts, which was considered anestrus. NR gilts had impaired development of reproductive tract characterized by absence of large follicles (diameter ≥ 6 mm), decreased number of corepus lutea and atrophy of uterus and ovary tissues. Circulating concentrations of IGF-I, kisspeptin, estradiol, progesterone and leptin were significantly lower in NR gilts than that in CON gilts. Nutrient restriction down-regulated gene expressions of kiss-1, G-protein coupled protein 54, gonadotropin-releasing hormone, estrogen receptor α, progesterone receptor, leptin receptor, follicle-stimulating hormone and luteinizing hormone and insulin-like growth factor I in hypothalamus-pituitary-gonadal axis of gilts. Collectively, nutrient restriction resulted in impairment of reproductive function and changes of hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis, which shed light on the underlying mechanism by which nutrient restriction influenced reproductive function.
Modeling mechanisms of vegetation change due to fire in a semi-arid ecosystem

USGS Publications Warehouse

White, J.D.; Gutzwiller, K.J.; Barrow, W.C.; Randall, L.J.; Swint, P.

2008-01-01

Vegetation growth and community composition in semi-arid environments is determined by water availability and carbon assimilation mechanisms specific to different plant types. Disturbance also impacts vegetation productivity and composition dependent on area affected, intensity, and frequency factors. In this study, a new spatially explicit ecosystem model is presented for the purpose of simulating vegetation cover type changes associated with fire disturbance in the northern Chihuahuan Desert region. The model is called the Landscape and Fire Simulator (LAFS) and represents physiological activity of six functional plant types incorporating site climate, fire, and seed dispersal routines for individual grid cells. We applied this model for Big Bend National Park, Texas, by assessing the impact of wildfire on the trajectory of vegetation communities over time. The model was initialized and calibrated based on landcover maps derived from Landsat-5 Thematic Mapper data acquired in 1986 and 1999 coupled with plant biomass measurements collected in the field during 2000. Initial vegetation cover change analysis from satellite data showed shrub encroachment during this time period that was captured in the simulated results. A synthetic 50-year climate record was derived from historical meteorological data to assess system response based on initial landcover conditions. This simulation showed that shrublands increased to the detriment of grass and yucca-ocotillo vegetation cover types indicating an ecosystem-level trajectory for shrub encroachment. Our analysis of simulated fires also showed that fires significantly reduced site biomass components including leaf area, stem, and seed biomass in this semi-arid ecosystem. In contrast to other landscape simulation models, this new model incorporates detailed physiological responses of functional plant types that will allow us to simulated the impact of increased atmospheric CO2 occurring with climate change coupled with fire
An empirical method for calculating melt compositions produced beneath mid-ocean ridges: for axis and off-axis (seamounts) melting application

NASA Astrophysics Data System (ADS)

Batiza, Rodey

1991-12-01

We present a new method for calculating the major element compositions of primary melts parental to mid-ocean ridge basalt (MORB). This model is based on the experimental data of Jaques and Green (1980), Falloon et al. (1988), and Falloon and Green (1987, 1988) which are ideal for this purpose. Our method is empirical and employs solid-liquid partition coefficients (Di) from the experiments. We empirically determine Di=f(P,F) and use this to calculate melt compositions produced by decompression-induced melting along an adiabat (column melting). Results indicate that most MORBs can be generated by 10-20% partial melting at initial pressures (P0) of 12-21 kbar. Our primary MORB melts have MgO=10-12 wt %. We fractionate these at low pressure to an MgO content of 8.0 wt% in order to interpret natural MORB liquids. This model allows us to calculate Po, Pf, To, Tf, and F for natural MORB melts. We apply the model to interpret MORB compositions and mantle upwelling patterns beneath a fast ridge (East Pacific Rise (EPR) 8°N to 14°N), a slow ridge (mid-Atlantic Ridge (MAR) at 26°S), and seamounts near the EPR (Lamont seamount chain). We find mantle temperature differences of up to 50°-60°C over distances of 30-50 km both across axis and along axis at the EPR. We propose that these are due to upward mantle flow in a weakly conductive (versus adiabatic) temperature gradient. We suggest that the EPR is fed by a wide (~100 km) zone of upwelling due to plate separation but has a central core of faster buoyant flow. An along-axis thermal dome between the Siqueiros transform and the 11°45' Overlapping Spreading Center (OSC) may represent such an upwelling; however, in general there is a poor correlation between mantle temperature, topography, and the segmentation pattern at the EPR. For the Lamont seamounts we find regular across-axis changes in Po and F suggesting that the melt zone pinches out off axis. This observation supports the idea that the EPR is fed by a broad

An empirical method for calculating melt compositions produced beneath mid-ocean ridges: Application for axis and off-axis (seamounts) melting

NASA Astrophysics Data System (ADS)

Niu, Yaoling; Batiza, Rodey

1991-12-01

We present a new method for calculating the major element compositions of primary melts parental to mid-ocean ridge basalt (MORB). This model is based on the experimental data of Jaques and Green (1980), Falloon et al. (1988), and Falloon and Green (1987, 1988) which are ideal for this purpose. Our method is empirical and employs solid-liquid partition coefficients (Di) from the experiments. We empirically determine Di = ƒ(P,F) and use this to calculate melt compositions produced by decompression-induced melting along an adiabat (column melting). Results indicate that most MORBs can be generated by 10-20% partial melting at initial pressures (P0) of 12-21 kbar. Our primary MORB melts have MgO = 10-12 wt %. We fractionate these at low pressure to an MgO content of 8.0 wt % in order to interpret natural MORB liquids. This model allows us to calculate Po, Pƒ, To, Tƒ, and F for natural MORB melts. We apply the model to interpret MORB compositions and mantle upwelling patterns beneath a fast ridge (East Pacific Rise (EPR)8°N to 14°N), a slow ridge (mid-Atlantic Ridge (MAR) at 26°S), and seamounts near the EPR (Lament seamount chain). We find mantle temperature differences of up to 50°-60°C over distances of 30-50 km both across axis and along axis at the EPR. We propose that these are due to upward mantle flow in a weakly conductive (versus adiabatic) temperature gradient. We suggest that the EPR is fed by a wide (-100 km) zone of upwelling due to plate separation but has a central core of faster buoyant flow. An along-axis thermal dome between the Siqueiros transform and the 11°45' Overlapping Spreading center (OSC) may represent such an upwelling; however, in general there is a poor correlation between mantle temperature, topography, and the segmentation pattern at the EPR. For the Lament seamounts we find regular across-axis changes in Po and F suggesting that the melt zone pinches out off axis. This observation supports the idea that the EPR is fed by a
The Advanced X-ray Imaging Satellite (AXIS)

NASA Astrophysics Data System (ADS)

Reynolds, Christopher S.; Mushotzky, Richard

2017-08-01

The Advanced X-ray Imaging Satellite (AXIS) will follow in the footsteps of the spectacularly successful Chandra X-ray Observatory with similar or higher angular resolution and an order of magnitude more collecting area in the 0.3-10keV band. These capabilities will enable major advances in many of the most active areas of astrophysics, including (i) mapping event horizon scale structure in AGN accretion disks and the determination of supermassive black hole (SMBH) spins through monitoring of gravitationally-microlensed quasars; (ii) dramatically deepening our understanding of AGN feedback in galaxies and galaxy clusters out to high-z through the direct imaging of AGN winds and the interaction of jets with the hot interstellar/intracluster medium; (iii) understanding the fueling of AGN by probing hot flows inside of the SMBH sphere of influence; (iv) obtaining geometric distance measurements using dust scattering halos. With a nominal 2028 launch, AXIS will be enormously synergistic with LSST, ALMA, WFIRST and ATHENA, and will be a valuable precursor to Lynx. AXIS is enabled by breakthroughs in the construction of light-weight X-ray optics from mono-crystalline silicon blocks, building on recent developments in the semiconductor industry. Here, we describe the straw-man concept for AXIS, some of the high profile science that this observatory will address, and how you can become involved.
Three-dimensional tool radius compensation for multi-axis peripheral milling

NASA Astrophysics Data System (ADS)

Chen, Youdong; Wang, Tianmiao

2013-05-01

Few function about 3D tool radius compensation is applied to generating executable motion control commands in the existing computer numerical control (CNC) systems. Once the tool radius is changed, especially in the case of tool size changing with tool wear in machining, a new NC program has to be recreated. A generic 3D tool radius compensation method for multi-axis peripheral milling in CNC systems is presented. The offset path is calculated by offsetting the tool path along the direction of the offset vector with a given distance. The offset vector is perpendicular to both the tangent vector of the tool path and the orientation vector of the tool axis relative to the workpiece. The orientation vector equations of the tool axis relative to the workpiece are obtained through homogeneous coordinate transformation matrix and forward kinematics of generalized kinematics model of multi-axis machine tools. To avoid cutting into the corner formed by the two adjacent tool paths, the coordinates of offset path at the intersection point have been calculated according to the transition type that is determined by the angle between the two tool path tangent vectors at the corner. Through the verification by the solid cutting simulation software VERICUT® with different tool radiuses on a table-tilting type five-axis machine tool, and by the real machining experiment of machining a soup spoon on a five-axis machine tool with the developed CNC system, the effectiveness of the proposed 3D tool radius compensation method is confirmed. The proposed compensation method can be suitable for all kinds of three- to five-axis machine tools as a general form.
The Anteroposterior Axis of the Proximal Tibia Can Change After Tibial Resection in Total Knee Arthroplasty: Computer Simulation Using Asian Osteoarthritis Knees.

PubMed

Ushio, Tetsuro; Mizu-Uchi, Hideki; Okazaki, Ken; Ma, Yuan; Kuwashima, Umito; Iwamoto, Yukihide

2017-03-01

We evaluated the effect of cutting surface on the anteroposterior (AP) axis of the proximal tibia using a 3-dimensional (3D) bone model to ensure proper tibial rotational alignment in total knee arthroplasty. 3D bone models were reconstructed from the preoperative computed tomography data of 93 Japanese osteoarthritis knees with varus deformity. The AP axis was defined as the perpendicular bisector of the medial and lateral condylar centers in a 3D coordinate system. Bone cutting of the proximal tibia was performed with various tibial posterior slopes (0°, 3°, 7°) to the mechanical axis, and we compared the AP axes before and after bone cutting. The AP axis before bone cutting crossed a point at about 16% (one-sixth) of the distance from the medial edge of the patellar tendon at its tibial attachment. The AP axis after bone cutting was significantly internally rotated at all posterior slopes: 4.1° at slope 0°, 3.0° at slope 3°, and 2.1° at slope 7°. The percentages of cases with differences of more than 3° or 5° were 66.7% and 34.4% at slope 0°, 53.8% and 24.7% at slope 3°, and 38.3% and 11.8% at slope 7°, respectively. The AP axis of the proximal tibia may be rotated internally after resection of the proximal tibia in total knee arthroplasty. Hence, surgeons should recognize the effect of changes in the cutting surface on rotational alignment of the proximal tibia. Copyright © 2016 Elsevier Inc. All rights reserved.
Diagnosis of co-morbid axis-I psychiatric disorders among women with newly diagnosed, untreated endocrine disorders.

PubMed

Fornaro, Michele; Iovieno, Nadia; Clementi, Nicoletta; Boscaro, Marco; Paggi, Francesca; Balercia, Giancarlo; Fava, Maurizio; Papakostas, George I

2010-12-01

To determine the prevalence of major depressive disorder (MDD) and other selected axis-I disorders among women with newly diagnosed, untreated endocrine disorders. Two hundred and eighteen consecutive women, aged 18-65, with newly diagnosed, untreated endocrine disorders were referred for potential diagnosis of co-morbid axis-I disorders with the use of the Structured Clinical Interview for Axis I-Patient Edition (SCID-P). The SCID-P was re-administered after 12 weeks. At baseline, 64 (29.3%) women met criteria for at least one axis-I disorder. Women who were diagnosed with hyperthyroidism were more likely to meet criteria for generalized anxiety disorder and panic disorder than women without hyperthyroidism. Nine of 154 (5.8 %) women who did not meet criteria for an axis-I disorder at baseline met criteria for at least one axis-I disorder during follow-up. Among them, the presence of diabetes mellitus was statistically correlated with a higher probability of developing major depressive disorder at follow-up. Although preliminary, our findings are consistent with previous studies and suggest an increased prevalence of MDD and other axis-I disorders among women with newly diagnosed endocrine disorders, providing further evidence suggesting that women with endocrine abnormalities may be at increased risk of depression and/or anxiety disorders.
Ankle-foot orthosis bending axis influences running mechanics.

PubMed

Russell Esposito, Elizabeth; Ranz, Ellyn C; Schmidtbauer, Kelly A; Neptune, Richard R; Wilken, Jason M

2017-07-01

Passive-dynamic ankle-foot orthoses (AFOs) are commonly prescribed to improve locomotion for people with lower limb musculoskeletal weakness. The clinical prescription and design process are typically qualitative and based on observational assessment and experience. Prior work examining the effect of AFO design characteristics generally excludes higher impact activities such as running, providing clinicians and researchers limited information to guide the development of objective prescription guidelines. The proximal location of the bending axis may directly influence energy storage and return and resulting running mechanics. The purpose of this study was to determine if the location of an AFO's bending axis influences running mechanics. Marker and force data were recorded as 12 participants with lower extremity weakness ran overground while wearing a passive-dynamic AFO with posterior struts manufactured with central (middle) and off-centered (high and low) bending axes. Lower extremity joint angles, moments, powers, and ground reaction forces were calculated and compared between limbs and across bending axis conditions. Bending axis produced relatively small but significant changes. Ankle range of motion increased as the bending axis shifted distally (p<0.003). Peak ankle power absorption was greater in the low axis than high (p=0.013), and peak power generation was greater in the low condition than middle or high conditions (p<0.009). Half of the participants preferred the middle bending axis, four preferred low and two preferred high. Overall, if greater ankle range of motion is tolerated, a low bending axis provides power and propulsive benefits during running, although individual preference and physical ability should also be considered. Published by Elsevier B.V.
Dynamic changes in the hypothalamic-pituitary-adrenal axis during growth hormone therapy in children with growth hormone deficiency: a multicenter retrospective study.

PubMed

Wang, Limin; Wang, Qian; Li, Guimei; Liu, Wendong

2015-09-01

The objective of this study was to investigate changes in the hypothalamic-pituitary-adrenal (HPA) axis after recombinant human growth hormone (rhGH) therapy. Subjects included children with growth hormone deficiency (GHD). We conducted a multicenter, retrospective study that assessed 72 GHD patients treated with rhGH during 6 months. Patients were classified into two groups: isolated GHD (IGHD; n=20) and multiple pituitary hormone deficiencies (MPHD; n=52). The HPA axis and other hormones were evaluated at baseline and every 3 months. In the MPHD group, 32 patients had adrenocorticotrophic hormone deficiency and received hydrocortisone before rhGH therapy. In the other 20/52 MPHD patients, the cortisol (COR) level was significantly reduced after rhGH therapy. Moreover, 10 patients showed low COR levels. In the IGHD group, COR levels also decreased, but remained within the normal range. During rhGH therapy, COR levels were reduced, particularly in patients with MPHD. HPA axis should be monitored during rhGH therapy.
14 CFR 21.97 - Approval of major changes in type design.

Code of Federal Regulations, 2010 CFR

2010-01-01

... must submit substantiating data and necessary descriptive data for inclusion in the type design. (b... major change in type design must— (1) Provide substantiating data and necessary descriptive data for... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Approval of major changes in type design...
Fetal endocrine and metabolic adaptations to hypoxia: the role of the hypothalamic-pituitary-adrenal axis

PubMed Central

Newby, Elizabeth A.; Myers, Dean A.

2015-01-01

In utero, hypoxia is a significant yet common stress that perturbs homeostasis and can occur due to preeclampsia, preterm labor, maternal smoking, heart or lung disease, obesity, and high altitude. The fetus has the extraordinary capacity to respond to stress during development. This is mediated in part by the hypothalamic-pituitary-adrenal (HPA) axis and more recently explored changes in perirenal adipose tissue (PAT) in response to hypoxia. Obvious ethical considerations limit studies of the human fetus, and fetal studies in the rodent model are limited due to size considerations and major differences in developmental landmarks. The sheep is a common model that has been used extensively to study the effects of both acute and chronic hypoxia on fetal development. In response to high-altitude-induced, moderate long-term hypoxia (LTH), both the HPA axis and PAT adapt to preserve normal fetal growth and development while allowing for responses to acute stress. Although these adaptations appear beneficial during fetal development, they may become deleterious postnatally and into adulthood. The goal of this review is to examine the role of the HPA axis in the convergence of endocrine and metabolic adaptive responses to hypoxia in the fetus. PMID:26173460
20 CFR 418.2205 - What is a major life-changing event?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What is a major life-changing event? 418.2205 Section 418.2205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income-Related... Year's Modified Adjusted Gross Income § 418.2205 What is a major life-changing event? We will follow...
20 CFR 418.2205 - What is a major life-changing event?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false What is a major life-changing event? 418.2205 Section 418.2205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income-Related... Year's Modified Adjusted Gross Income § 418.2205 What is a major life-changing event? We will follow...
20 CFR 418.2205 - What is a major life-changing event?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What is a major life-changing event? 418.2205 Section 418.2205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income-Related... Year's Modified Adjusted Gross Income § 418.2205 What is a major life-changing event? We will follow...
20 CFR 418.2205 - What is a major life-changing event?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false What is a major life-changing event? 418.2205 Section 418.2205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income-Related... Year's Modified Adjusted Gross Income § 418.2205 What is a major life-changing event? We will follow...
Stream Discharge and Evapotranspiration Responses to Climate Change and Their Associated Uncertainties in a Large Semi-Arid Basin

NASA Astrophysics Data System (ADS)

Bassam, S.; Ren, J.

2017-12-01

Predicting future water availability in watersheds is very important for proper water resources management, especially in semi-arid regions with scarce water resources. Hydrological models have been considered as powerful tools in predicting future hydrological conditions in watershed systems in the past two decades. Streamflow and evapotranspiration are the two important components in watershed water balance estimation as the former is the most commonly-used indicator of the overall water budget estimation, and the latter is the second biggest component of water budget (biggest outflow from the system). One of the main concerns in watershed scale hydrological modeling is the uncertainties associated with model prediction, which could arise from errors in model parameters and input meteorological data, or errors in model representation of the physics of hydrological processes. Understanding and quantifying these uncertainties are vital to water resources managers for proper decision making based on model predictions. In this study, we evaluated the impacts of different climate change scenarios on the future stream discharge and evapotranspiration, and their associated uncertainties, throughout a large semi-arid basin using a stochastically-calibrated, physically-based, semi-distributed hydrological model. The results of this study could provide valuable insights in applying hydrological models in large scale watersheds, understanding the associated sensitivity and uncertainties in model parameters, and estimating the corresponding impacts on interested hydrological process variables under different climate change scenarios.
20 CFR 418.1205 - What is a major life-changing event?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false What is a major life-changing event? 418.1205 Section 418.1205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare Part B... Gross Income § 418.1205 What is a major life-changing event? For the purposes of this subpart, we will...
The AGE-RAGE axis in an Arab population: The United Arab Emirates Healthy Futures (UAEHFS) pilot study.

PubMed

Inman, Claire K; Aljunaibi, Abdullah; Koh, Hyunwook; Abdulle, Abdishakur; Ali, Raghib; Alnaeemi, Abdullah; Al Zaabi, Eiman; Oumeziane, Naima; Al Bastaki, Marina; Al-Houqani, Mohammed; Al-Maskari, Fatma; Al Dhaheri, Ayesha; Shah, Syed M; Abdel Wareth, Laila; Al Mahmeed, Wael; Alsafar, Habiba; Al Anouti, Fatme; Al Hosani, Ayesha; Haji, Muna; Galani, Divya; O'Connor, Matthew J; Ahn, Jiyoung; Kirchhoff, Tomas; Sherman, Scott; Hayes, Richard B; Li, Huilin; Ramasamy, Ravichandran; Schmidt, Ann Marie

2017-12-01

The transformation of the United Arab Emirates (UAE) from a semi-nomadic to a high income society has been accompanied by increasing rates of obesity and Type 2 diabetes mellitus. We examined if the AGE-RAGE (receptor for advanced glycation endproducts) axis is associated with obesity and diabetes mellitus in the pilot phase of the UAE Healthy Futures Study (UAEHFS). 517 Emirati subjects were enrolled and plasma/serum levels of AGE, carboxy methyl lysine (CML)-AGE, soluble (s)RAGE and endogenous secretory (es)RAGE were measured along with weight, height, waist and hip circumference (WC/HC), blood pressure, HbA1c, Vitamin D levels and routine chemistries. The relationship between the AGE-RAGE axis and obesity and diabetes mellitus was tested using proportional odds models and linear regression. After covariate adjustment, AGE levels were significantly associated with diabetes status. Levels of sRAGE and esRAGE were associated with BMI and levels of sRAGE were associated with WC/HC. The AGE-RAGE axis is associated with diabetes status and obesity in this Arab population. Prospective serial analysis of this axis may identify predictive biomarkers of obesity and cardiometabolic dysfunction in the UAEHFS.
Land Cover Land Use change and soil organic carbon under climate variability in the semi-arid West African Sahel (1960-2050)

NASA Astrophysics Data System (ADS)

Dieye, Amadou M.

Land Cover Land Use (LCLU) change affects land surface processes recognized to influence climate change at local, national and global levels. Soil organic carbon is a key component for the functioning of agro-ecosystems and has a direct effect on the physical, chemical and biological characteristics of the soil. The capacity to model and project LCLU change is of considerable interest for mitigation and adaptation measures in response to climate change. A combination of remote sensing analyses, qualitative social survey techniques, and biogeochemical modeling was used to study the relationships between climate change, LCLU change and soil organic carbon in the semi-arid rural zone of Senegal between 1960 and 2050. For this purpose, four research hypotheses were addressed. This research aims to contribute to an understanding of future land cover land use change in the semi-arid West African Sahel with respect to climate variability and human activities. Its findings may provide insights to enable policy makers at local to national levels to formulate environmentally and economically adapted policy decisions. This dissertation research has to date resulted in two published and one submitted paper.
Intra-seasonal NDVI change projections in semi-arid Africa

USGS Publications Warehouse

Funk, Christopher C.; Brown, Molly E.

2006-01-01

Early warning systems (EWS) tend to focus on the identification of slow onset disasters such famine and epidemic disease. Since hazardous environmental conditions often precede disastrous outcomes by many months, effective monitoring via satellite and in situ observations can successfully guide mitigation activities. Accurate short term forecasts of NDVI could increase lead times, making early warning earlier. This paper presents a simple empirical model for making 1 to 4 month NDVI projections. These statistical projections are based on parameterized satellite rainfall estimates (RFE) and relative humidity demand (RHD). A quasi-global, 1 month ahead, 1° study demonstrates reasonable accuracies in many semi-arid regions. In Africa, a 0.1° cross-validated skill assessment quantifies the technique's applicability at 1 to 4 month forecast intervals. These results suggest that useful projections can be made over many semi-arid, food insecure regions of Africa, with plausible extensions to drought prone areas of Asia, Australia and South America.
Conjugation of both on-axis and off-axis light in Nipkow disk confocal microscope to increase availability of incoherent light source.

PubMed

Saito, Kenta; Arai, Yoshiyuki; Zhang, Jize; Kobayashi, Kentaro; Tani, Tomomi; Nagai, Takeharu

2011-01-01

Laser-scanning confocal microscopy has been employed for exploring structures at subcellular, cellular and tissue level in three dimensions. To acquire the confocal image, a coherent light source, such as laser, is generally required in conventional single-point scanning microscopy. The illuminating beam must be focused onto a small spot with diffraction-limited size, and this determines the spatial resolution of the microscopy system. In contrast, multipoint scanning confocal microscopy using a Nipkow disk enables the use of an incoherent light source. We previously demonstrated successful application of a 100 W mercury arc lamp as a light source for the Yokogawa confocal scanner unit in which a microlens array was coupled with a Nipkow disk to focus the collimated incident light onto a pinhole (Saito et al., Cell Struct. Funct., 33: 133-141, 2008). However, transmission efficiency of incident light through the pinhole array was low because off-axis light, the major component of the incident light, was blocked by the non-aperture area of the disk. To improve transmission efficiency, we propose an optical system in which off-axis light is able to be transmitted through pinholes surrounding the pinhole located on the optical axis of the collimator lens. This optical system facilitates the use of not only the on-axis but also the off-axis light such that the available incident light is considerably improved. As a result, we apply the proposed system to high-speed confocal and multicolor imaging both with a satisfactory signal-to-noise ratio.
Single-Axis Accelerometer

NASA Technical Reports Server (NTRS)

Tucker, Dennis Stephen (Inventor); Capo-Lugo, Pedro A. (Inventor)

2016-01-01

A single-axis accelerometer includes a housing defining a sleeve. An object/mass is disposed in the sleeve for sliding movement therein in a direction aligned with the sleeve's longitudinal axis. A first piezoelectric strip, attached to a first side of the object and to the housing, is longitudinally aligned with the sleeve's longitudinal axis. The first piezoelectric strip includes a first strip of a piezoelectric material with carbon nanotubes substantially aligned along a length thereof. A second piezoelectric strip, attached to a second side of the object and to the housing, is longitudinally aligned with the sleeve's longitudinal axis. The second piezoelectric strip includes a second strip of the piezoelectric material with carbon nanotubes substantially aligned along a length thereof. A voltage sensor is electrically coupled to at least one of the first and second piezoelectric strips.

The Joint Structure of DSM–IV Axis I and Axis II Disorders

PubMed Central

Røysamb, Espen; Tambs, Kristian; Ørstavik, Ragnhild E.; Torgersen, Svenn; Kendler, Kenneth S.; Neale, Michael C.; Aggen, Steven H.; Reichborn-Kjennerud, Ted

2011-01-01

The Diagnostic and Statistical Manual (4th ed. [DSM–IV]; American Psychiatric Association, 1994) distinction between clinical disorders on Axis I and personality disorders on Axis II has become increasingly controversial. Although substantial comorbidity between axes has been demonstrated, the structure of the liability factors underlying these two groups of disorders is poorly understood. The aim of this study was to determine the latent factor structure of a broad set of common Axis I disorders and all Axis II personality disorders and thereby to identify clusters of disorders and account for comorbidity within and between axes. Data were collected in Norway, through a population-based interview study (N = 2,794 young adult twins). Axis I and Axis II disorders were assessed with the Composite International Diagnostic Interview (CIDI) and the Structured Interview for DSM–IV Personality (SIDP–IV), respectively. Exploratory and confirmatory factor analyses were used to investigate the underlying structure of 25 disorders. A four-factor model fit the data well, suggesting a distinction between clinical and personality disorders as well as a distinction between broad groups of internalizing and externalizing disorders. The location of some disorders was not consistent with the DSM–IV classification; antisocial personality disorder belonged primarily to the Axis I externalizing spectrum, dysthymia appeared as a personality disorder, and borderline personality disorder appeared in an interspectral position. The findings have implications for a meta-structure for the DSM. PMID:21319931
Simulating the hydrologic impacts of land cover and climate changes in a semi-arid watershed

EPA Pesticide Factsheets

Changes in climate and land cover are among the principal variables affecting watershed hydrology.This paper uses a cell-based model to examine the hydrologic impacts of climate and land-cover changes in thesemi-arid Lower Virgin River (LVR) watershed located upstream of Lake Mead, Nevada, USA. The cell-basedmodel is developed by considering direct runoff based on the Soil Conservation Service - Curve Number (SCSCN)method and surplus runoff based on the Thornthwaite water balance theory. After calibration and validation,the model is used to predict LVR discharge under future climate and land-cover changes. The hydrologicsimulation results reveal climate change as the dominant factor and land-cover change as a secondary factor inregulating future river discharge. The combined effects of climate and land-cover changes will slightly increaseriver discharge in summer but substantially decrease discharge in winter. This impact on water resources deservesattention in climate change adaptation planning.This dataset is associated with the following publication:Chen, H., S. Tong, H. Yang, and J. Yang. Simulating the hydrologic impacts of land cover and climate changes in a semi-arid watershed. Hydrological Sciences Journal. IAHS LIMITED, Oxford, UK, 60(10): 1739-1758, (2015).
Modeling secular changes in seawater chemistry accurately requires inclusion of environmental controls on low-temperature, off-axis, hydrothermal fluxes

NASA Astrophysics Data System (ADS)

Coogan, L. A.; Dosso, S. E.; Higgins, J. A.

2014-12-01

There are sharp rises in the Sr- and Li-isotopic composition of seawater at the Eocene-Oligocene boundary that are generally thought to be associated with Himalayan uplift and associated climatic changes and continental weathering variability. In modeling such data the norm is to hold the chemical fluxes associated with off-axis hydrothermal circulation through the oceanic crust constant while varying the river fluxes (and/or isotopic ratios). There is, however, no a priori reason to assume the chemical fluxes (or isotopic compositions) associated with off-axis hydrothermal systems should stay constant. Instead, changing environmental conditions (e.g. seawater composition and bottom water temperature) will lead to changes in these fluxes. An alternative model to explain the sharp rise in the Sr- and Li-isotopic composition of seawater at the Eocene-Oligocene boundary is cooling of the deep ocean. Decreased reaction rates in the oceanic crust, due to decreasing temperature, can be shown to lead to a decrease in the flux of unradiogenic Sr into the ocean. The magnitude matches, within uncertainty, that required to explain the increase in seawater Sr-isotopic composition [Coogan and Dosso, in review]. The story for Li is more uncertain. Two factors may lead to smaller effective fractionation factors between seawater and the (large) Li sink in the oceanic crust when bottom water is warmer: (i) higher temperature will decrease the isotopic fractionation factor; (ii) the more extensive fluid-rock reaction in the ocean crust when bottom water is warmer will make Li uptake by the oceanic crust more efficient. All other things being equal this will lead to a lower Li content of seawater. In turn, a lower Li content in seawater will mean that for a given Li-uptake rate by the crust the effective fractionation factor is smaller, due to Rayleigh distillation of Li-isotopes during fluid-rock reaction in the oceanic crust. In combination these factors predict a significant (many
Experimental hyperthyroidism and central mediators of stress axis and thyroid axis activity in common carp (Cyprinus carpio L.).

PubMed

Geven, Edwin J W; Verkaar, Folkert; Flik, Gert; Klaren, Peter H M

2006-12-01

The effect of experimental hyperthyroidism, realized by T(4) injection, on central mediators of the hypothalamo-pituitary-interrenal axis (HPI-axis) in common carp (Cyprinus carpio L.) was studied. Our results show that hyperthyroidism evokes a marked 3.2-fold reduction in basal plasma cortisol levels. Corticotropin-releasing hormone-binding protein (CRH-BP) mRNA levels in the hypothalamus, measured by real-time quantitative PCR, were significantly elevated by 40%, but CRH, urotensin-I, prepro-TRH, prohormone convertase-1 (PC1), and POMC mRNA levels were unchanged. In the pituitary pars distalis, PC1, CRH receptor-1, and POMC mRNA levels were unaffected, as was ACTH content. Plasma alpha-MSH concentrations were significantly elevated by 30% in hyperthyroid fish, and this was reflected in PC1 and POMC mRNA levels in pituitary pars intermedia that were increased 1.5- and 2.4-fold respectively. The alpha-MSH content of the pars intermedia was unchanged. Hyperthyroidism has profound effects on the basal levels of a central mediator, i.e., CRH-BP, of HPI-axis function in unstressed carp in vivo, and we conclude that HPI- and hypothalamo-pituitary-thyroid-axis functions are strongly interrelated. We suggest that the changes in plasma cortisol, thyroid hormone, and alpha-MSH levels reflect their concerted actions on energy metabolism.
Global Gene Expression Change Induced by Major Thoracoabdominal Surgery.

PubMed

Allen, Casey J; Griswold, Anthony J; Schulman, Carl I; Sleeman, Danny; Levi, Joe U; Livingstone, Alan S; Proctor, Kenneth G

2017-12-01

To test the hypothesis that major thoracoabdominal surgery induces gene expression changes associated with adverse outcomes. Widely different traumatic injuries evoke surprisingly similar gene expression profiles, but there is limited information on whether the iatrogenic injury caused by major surgery is associated with similar patterns. With informed consent, blood samples were obtained from 50 patients before and after open transhiatal esophagectomy or pancreaticoduodenectomy. Twelve cases with complicated recoveries (death, infection, venous thromboembolism) were matched with 12 cases with uneventful recoveries. Global gene expression was assayed using human microarray chips. A 2-fold change with a corrected P < 0.05 was considered differentially expressed. In these 24 patients, 522 genes were differentially expressed after surgery; 248 (48%) were upregulated (innate immunity and inflammation) and 274 (52%) were downregulated [adaptive immunity (antigen presentation, T-cell function)]. Hierarchical clustering of the profile reliably predicted pre- and postoperative status. The within-patient change was 3.08 ± 0.91-fold. There was no measurable association with age, malignancy, procedure, surgery length, operative blood loss, or transfusion requirements, but was positively associated with postoperative infection (3.81 ± 0.97 vs 2.79 ± 0.73; P = 0.009) and hospital length of stay (r = 0.583, P = 0.003). Venous thromboembolism and mortality each occurred in one patient, thus no associations were possible. Major surgery induces a quantifiable pattern of gene expression change that is associated with adverse outcome. This could reflect early impaired adaptive immunity and suggests potential therapeutic targets to improve postoperative recovery.
Maternal hypothalamic-pituitary-adrenal axis response to foraging uncertainty: A model of individual vs. social allostasis and the "Superorganism Hypothesis"

PubMed Central

Coplan, Jeremy D.; Karim, Asif; Rozenboym, Anna; Smith, Eric L. P.; Kral, John G.; Rosenblum, Leonard A.

2017-01-01

Introduction Food insecurity is a major global contributor to developmental origins of adult disease. The allostatic load of maternal food uncertainty from variable foraging demand (VFD) activates corticotropin-releasing factor (CRF) without eliciting hypothalamic-pituitary-adrenal (HPA) activation measured on a group level. Individual homeostatic adaptations of the HPA axis may subserve second-order homeostasis, a process we provisionally term “social allostasis.” We postulate that maternal food insecurity induces a “superorganism” state through coordination of individual HPA axis response. Methods Twenty-four socially-housed bonnet macaque maternal-infant dyads were exposed to 16 weeks of alternating two-week epochs of low or high foraging demand shown to compromise normative maternal-infant rearing. Cerebrospinal fluid (CSF) CRF concentrations and plasma cortisol were measured pre- and post-VFD. Dyadic distance was measured, and blinded observers performed pre-VFD social ranking assessments. Results Despite marked individual cortisol responses (mean change = 20%) there was an absence of maternal HPA axis group mean response to VFD (0%). Whereas individual CSF CRF concentrations change = 56%, group mean did increase 25% (p = 0.002). Our "dyadic vulnerability" index (low infant weight, low maternal weight, subordinate maternal social status and reduced dyadic distance) predicted maternal cortisol decreases (p < 0.0001) whereas relatively “advantaged” dyads exhibited maternal cortisol increases in response to VFD exposure. Comment In response to a chronic stressor, relative dyadic vulnerability plays a significant role in determining the directionality and magnitude of individual maternal HPA axis responses in the service of maintaining a “superorganism” version of HPA axis homeostasis, provisionally termed “social allostasis.” PMID:28880949
Fire modulates climate change response of simulated aspen distribution across topoclimatic gradients in a semi-arid montane landscape

USGS Publications Warehouse

Yang, Jian; Weisberg, Peter J.; Shinneman, Douglas; Dilts, Thomas E.; Earnst, Susan L.; Scheller, Robert M

2015-01-01

Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving forces along topoclimatic gradients. Objective This study is set to evaluate how aspen distribution might shift in response to different climate-fire scenarios in a semi-arid montane landscape, and quantify the influence of fire regime along topoclimatic gradients. Methods We used a novel integration of a forest landscape succession and disturbance model (LANDIS-II) with a fine-scale climatic water deficit approach to simulate dynamics of aspen and associated conifer and shrub species over the next 150 years under various climate-fire scenarios. Results Simulations suggest that many aspen stands could persist without fire for centuries under current climate conditions. However, a simulated 2–5 °C increase in temperature caused a substantial reduction of aspen coverage at lower elevations and a modest increase at upper elevations, leading to an overall reduction of aspen range at the landscape level. Increasing fire activity may favor aspen increase at its upper elevation limits adjacent to coniferous forest, but may also favor reduction of aspen at lower elevation limits adjacent to xeric shrubland. Conclusions Our study highlights the importance of incorporating fine-scale terrain effects on climatic water deficit and ecohydrology when modeling species distribution response to climate change. This modeling study suggests that climate mitigation and adaptation strategies that use fire would benefit from consideration of spatial context at landscape scales.
Spatiotemporal reference evapotranspiration changes in humid and semi-arid regions of Iran: past trends and future projections

NASA Astrophysics Data System (ADS)

Nouri, Milad; Homaee, Mehdi; Bannayan, Mohammad

2017-06-01

This study was undertaken to investigate the reference evapotranspiration (ET0) changes in semi-arid and humid regions of Iran during the past (1966-2010) and future (2011-2099). For detecting possible trend in ET0 over 1966-2010, the Mann-Kendall trend test was employed. The outputs of Hadley Centre coupled model version 3 (HadCM3) and the third generation couple global climate model (CGCM3) under A2, B2, and A1B emission scenarios were also used to simulate the future ET0 changes by statistical downscaling model (SDSM). The results indicated upward trends in annual ET0 during 1966-2010 in the most sites. Furthermore, the significant increasing ET0 trends were identified for 54.5, 18.2, 27.3, 22.7, and 36.3% of studied locations during winter, spring, summer, autumn, and entire year, respectively. Positive trends in ET0 were mostly found in northeast, west, and northwest Iran, and insignificant downward ET0 trends were primarily detected in southwestern and southern stations in 1966-2010. The ET0 changes were attributed to wind speed changes in semi-arid regions and mean temperature changes in humid areas in the past period. An increase in ET0 was projected under all scenarios due mainly to temperature rise and declined relative humidity in the investigated regions from 2011 to 2100. Averaged over all stations, the lowest and highest ET0 increment were, respectively, modeled for autumn and summer using CGCM3 outputs and winter and autumn using HadCM3 outputs. Given significant ET0 increase over the twenty-first century, appropriate adaptive measures are required to reduce negative impacts of climate change on water resources and agricultural productions.
20 CFR 418.2210 - What is not a major life-changing event?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What is not a major life-changing event? 418.2210 Section 418.2210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income... Recent Tax Year's Modified Adjusted Gross Income § 418.2210 What is not a major life-changing event? We...
20 CFR 418.2210 - What is not a major life-changing event?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What is not a major life-changing event? 418.2210 Section 418.2210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income... Recent Tax Year's Modified Adjusted Gross Income § 418.2210 What is not a major life-changing event? We...
Change of Academic Major: The Influence of Broad and Narrow Personality Traits

ERIC Educational Resources Information Center

Foster, N. A.

2017-01-01

The relationship between academic major change and ten personality traits (the Big Five and five narrow traits), was investigated in a sample of 437 college undergraduates. Contrary to expectations, Career Decidedness and Optimism were positively related to academic major change, regardless of class ranking. When parsing data by college year,…
20 CFR 418.2210 - What is not a major life-changing event?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false What is not a major life-changing event? 418.2210 Section 418.2210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Income... Recent Tax Year's Modified Adjusted Gross Income § 418.2210 What is not a major life-changing event? We...
20 CFR 418.1210 - What is not a major life-changing event?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false What is not a major life-changing event? 418.1210 Section 418.1210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare... Adjusted Gross Income § 418.1210 What is not a major life-changing event? We will not consider events other...
20 CFR 418.1210 - What is not a major life-changing event?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false What is not a major life-changing event? 418.1210 Section 418.1210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare... Adjusted Gross Income § 418.1210 What is not a major life-changing event? We will not consider events other...
75 FR 41084 - Amendments to Regulations Regarding Major Life-Changing Events Affecting Income-Related Monthly...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-15

... to Regulations Regarding Major Life-Changing Events Affecting Income-Related Monthly Adjustment... major life-changing events for the Medicare Part B income- related monthly adjustment amount (IRMAA) and what evidence we require to support a claim of a major life-changing event. Recent changes in the...
Magnetization reversal in crossed double elliptic permalloy nanodisks studied by micromagnetic simulation

NASA Astrophysics Data System (ADS)

Mishra, Amaresh Chandra; Giri, R.

2018-05-01

The remanent state of elliptical permalloy nanodisks depends on the orientation of the applied magnetic field with respect to the major and minor axes of the nanodisks [A. C. Mishra, Int. J. Mod. Phys. B 30, 1650192 (2016)]. The remanent state is usually an onion state if the external magnetic field is along the major axis, and is a vortex state if the external magnetic field is along the minor axis. In this work, we have analyzed the magnetization reversal of a crossed elliptic disk of permalloy using micromagnetic simulation. This is a new shape where two identical elliptic disks with semi-major axis of length a and semi-minor axis of length b intersect such that they are perpendicular to each other. If the value of b is very close to that of a, then the remanent state is a near saturation state. As the ratio a/b goes down, new complex remanent states are observed. The hysteresis loss is found to be decreased gradually with the increment of b for a given value of b.
Rearing Mozambique tilapia in tidally-changing salinities: Effects on growth and the growth hormone/insulin-like growth factor I axis.

PubMed

Moorman, Benjamin P; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

2016-08-01

The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish. Copyright © 2016 Elsevier Inc. All rights reserved.
Hybrid shallow on-axis and deep off-axis hydrothermal circulation at fast-spreading ridges.

PubMed

Hasenclever, Jörg; Theissen-Krah, Sonja; Rüpke, Lars H; Morgan, Jason P; Iyer, Karthik; Petersen, Sven; Devey, Colin W

2014-04-24

Hydrothermal flow at oceanic spreading centres accounts for about ten per cent of all heat flux in the oceans and controls the thermal structure of young oceanic plates. It also influences ocean and crustal chemistry, provides a basis for chemosynthetic ecosystems, and has formed massive sulphide ore deposits throughout Earth's history. Despite this, how and under what conditions heat is extracted, in particular from the lower crust, remains largely unclear. Here we present high-resolution, whole-crust, two- and three-dimensional simulations of hydrothermal flow beneath fast-spreading ridges that predict the existence of two interacting flow components, controlled by different physical mechanisms, that merge above the melt lens to feed ridge-centred vent sites. Shallow on-axis flow structures develop owing to the thermodynamic properties of water, whereas deeper off-axis flow is strongly shaped by crustal permeability, particularly the brittle-ductile transition. About 60 per cent of the discharging fluid mass is replenished on-axis by warm (up to 300 degrees Celsius) recharge flow surrounding the hot thermal plumes, and the remaining 40 per cent or so occurs as colder and broader recharge up to several kilometres away from the axis that feeds hot (500-700 degrees Celsius) deep-rooted off-axis flow towards the ridge. Despite its lower contribution to the total mass flux, this deep off-axis flow carries about 70 per cent of the thermal energy released at the ridge axis. This combination of two flow components explains the seismically determined thermal structure of the crust and reconciles previously incompatible models favouring either shallower on-axis or deeper off-axis hydrothermal circulation.
Sclerochronology - tool for uncovering environmental drivers in a semi-enclosed sea

NASA Astrophysics Data System (ADS)

Vilibic, I.; Peharda, M.; Dzoic, T.; Markulin, K.; Dunic, N.; Mihanovic, H.; Gacic, M.; Black, B.; Uvanovic, H.; Ezgeta-Balic, D.; Sepic, J.; Kovac, Z.; Zupan, I.

2017-12-01

A number of proxy-based methods have been developed in detection of long-term environmental changes. Among them is sclerochronology which, through analysis of inter annular variations in widths of growth increments, has been advancing in recent decades. Albeit the main focus has been directed towards species living over centuries and in cold seas (primarily Arctica islandica), application of sclerochronology in temperate seas has potential to contribute toward better understanding of physical and environmental properties and processes in semi-enclosed seas. Here, we are presenting the major results of the project SCOOL (Sclerochronology as a tool for detecting long-term Adriatic environmental changes, http://www.izor.hr/web/scool), aiming to relate relatively long-lived bivalve species Glycymeris pilosa to the major environmental drivers in a semi-enclosed sea of the Mediterranean, the Adriatic Sea. The open Adriatic Sea is known to be dominated by quasi-decadal oscillations in thermohaline and biogeochemical properties driven by the dense water formation, so a question has been posed to quantify its role in driving the bivalve growth with respect to other environmental drivers (like heat fluxes, river discharges, precipitation). It seems that these basin-wide oscillations are dominating over locally-driven processes, even in coastal regions that include very shallow northern Adriatic. The northern Adriatic has been previously considered as quasi-separated from the basin-wide dynamics; such conclusions have been reached from multi-decadal in situ sampling series of different physical and chemical parameters. Therefore, sclerochronology is documented to be a reliable tool for detection of environmental drivers in a coastal temperate sea.
Inter-annual Variability of Evapotranspiration in a Semi-arid Oak-savanna Ecosystem: Measured and Modeled Buffering to Precipitation Changes

NASA Astrophysics Data System (ADS)

Raz-Yaseef, N.; Sonnentag, O.; Kobayashi, H.; Baldocchi, D. D.

2010-12-01

Precipitation (P) is the primary control on vegetation dynamics and productivity, implying that climate induced disturbances in frequency and timing of P are intimately coupled with fluxes of carbon, water and energy. Future climate change is expected to increase extreme rainfall events as well as droughts, suggesting linked vegetation changes to an unknown extent. Semi-arid climates experience large inter-annual variability (IAV) in P, creating natural conditions adequate to study how year-to-year changes in P affect atmosphere-biosphere fluxes. We used a 10-year flux database collected at a semi-arid savanna site in order to: (1) define IAV in P by means of frequency and timing; (2) investigate how changes in P affect the ecohydrology of the forest and its partitioning into the main vapor fluxes, and (3) evaluate model capability to predict IAV of carbon and water fluxes above and below the canopy. This is based on the perception that the capability of process-oriented models to construct the deviation, and not the average, is important in order to correctly predict ecosystem sensitivity to climate change. Our research site was a low density and low LAI (0.8) semi-arid (P=523±180 mm yr-1) savanna site, combined of oaks and grass, and located at Tonzi ranch, California. Measurements of carbon and water fluxes above and below the tree canopy using eddy covariance and supplementary measurements have been made since 2001. Measured fluxes were compared to modeled based on two bio-meteorological process-oriented ecosystem models: BEPS and 3D-CAONAK. Our results show that IAV in P was large, and standard deviation (STD) was 38% of the average. Accordingly, the wet soil period (measured volumetric water content > 8%) varied between 156 days in dry years to 301 days in wet years. IAV of the vapor fluxes were lower than that of P (STD was 17% for the trees and 23% for the floor components), suggesting on ecosystem buffering to changes in P. The timing of grass green up

Optical diffraction tomography: accuracy of an off-axis reconstruction

NASA Astrophysics Data System (ADS)

Kostencka, Julianna; Kozacki, Tomasz

2014-05-01

Optical diffraction tomography is an increasingly popular method that allows for reconstruction of three-dimensional refractive index distribution of semi-transparent samples using multiple measurements of an optical field transmitted through the sample for various illumination directions. The process of assembly of the angular measurements is usually performed with one of two methods: filtered backprojection (FBPJ) or filtered backpropagation (FBPP) tomographic reconstruction algorithm. The former approach, although conceptually very simple, provides an accurate reconstruction for the object regions located close to the plane of focus. However, since FBPJ ignores diffraction, its use for spatially extended structures is arguable. According to the theory of scattering, more precise restoration of a 3D structure shall be achieved with the FBPP algorithm, which unlike the former approach incorporates diffraction. It is believed that with this method one is allowed to obtain a high accuracy reconstruction in a large measurement volume exceeding depth of focus of an imaging system. However, some studies have suggested that a considerable improvement of the FBPP results can be achieved with prior propagation of the transmitted fields back to the centre of the object. This, supposedly, enables reduction of errors due to approximated diffraction formulas used in FBPP. In our view this finding casts doubt on quality of the FBPP reconstruction in the regions far from the rotation axis. The objective of this paper is to investigate limitation of the FBPP algorithm in terms of an off-axis reconstruction and compare its performance with the FBPJ approach. Moreover, in this work we propose some modifications to the FBPP algorithm that allow for more precise restoration of a sample structure in off-axis locations. The research is based on extensive numerical simulations supported with wave-propagation method.
Sodium reduction in New Zealand requires major behaviour change.

PubMed

Lofthouse, Catherine; Te Morenga, Lisa; McLean, Rachael

2016-10-01

This pilot study examined the feasibility of adherence to a low sodium diet in a sample of healthy New Zealand adults. It also addressed whether following a low sodium diet was accompanied by changes in intakes of other nutrients that influence cardiovascular risk. Eleven healthy adults provided dietary intake data and a 24-hour urine collection at baseline and follow-up. They then received nutritional counselling based on the World Health Organization recommendation for sodium intake (<2000 mg/day) and received ongoing nutritional support while undertaking a low sodium diet for four weeks. At the end of the four-week period, participants completed a semi-structured interview that elicited participants' opinions on barriers and facilitators to following a low sodium diet and explored changes in participants' dietary habits and behaviours. Thematic analysis revealed that adherence to a low sodium diet required substantial changes to participants' usual food purchasing and preparation habits. Participants reported that lack of control over the sodium content of meals eaten away from the home, the complex and time-consuming nature of interpreting nutrition information labels, and difficulty identifying suitable snacks were barriers to adherence. Detailed meal planning and cooking from scratch, using flavour replacements, reading food labels to identify low sodium foods, receiving support from other people and receiving tailored nutrition advice were facilitators. Mean sodium intake reduced over the period, accompanied by a decrease in mean intake of total fat. These factors suggest that sodium reduction in New Zealand adults was feasible. However, considerable changes to eating behaviours were required. Copyright © 2016 Elsevier Ltd. All rights reserved.
SemiBoost: boosting for semi-supervised learning.

PubMed

Mallapragada, Pavan Kumar; Jin, Rong; Jain, Anil K; Liu, Yi

2009-11-01

Semi-supervised learning has attracted a significant amount of attention in pattern recognition and machine learning. Most previous studies have focused on designing special algorithms to effectively exploit the unlabeled data in conjunction with labeled data. Our goal is to improve the classification accuracy of any given supervised learning algorithm by using the available unlabeled examples. We call this as the Semi-supervised improvement problem, to distinguish the proposed approach from the existing approaches. We design a metasemi-supervised learning algorithm that wraps around the underlying supervised algorithm and improves its performance using unlabeled data. This problem is particularly important when we need to train a supervised learning algorithm with a limited number of labeled examples and a multitude of unlabeled examples. We present a boosting framework for semi-supervised learning, termed as SemiBoost. The key advantages of the proposed semi-supervised learning approach are: 1) performance improvement of any supervised learning algorithm with a multitude of unlabeled data, 2) efficient computation by the iterative boosting algorithm, and 3) exploiting both manifold and cluster assumption in training classification models. An empirical study on 16 different data sets and text categorization demonstrates that the proposed framework improves the performance of several commonly used supervised learning algorithms, given a large number of unlabeled examples. We also show that the performance of the proposed algorithm, SemiBoost, is comparable to the state-of-the-art semi-supervised learning algorithms.
Spacecraft Formation Flying Maneuvers Using Linear Quadratic Regulation With No Radial Axis Inputs

NASA Technical Reports Server (NTRS)

Starin, Scott R.; Yedavalli, R. K.; Sparks, Andrew G.; Bauer, Frank H. (Technical Monitor)

2001-01-01

Regarding multiple spacecraft formation flying, the observation has been made that control thrust need only be applied coplanar to the local horizon to achieve complete controllability of a two-satellite (leader-follower) formation. A formulation of orbital dynamics using the state of one satellite relative to another is used. Without the need for thrust along the radial (zenith-nadir) axis of the relative reference frame, propulsion system simplifications and weight reduction may be accomplished. This work focuses on the validation of this control system on its own merits, and in comparison to a related system which does provide thrust along the radial axis of the relative frame. Maneuver simulations are performed using commercial ODE solvers to propagate the Keplerian dynamics of a controlled satellite relative to an uncontrolled leader. These short maneuver simulations demonstrate the capacity of the controller to perform changes from one formation geometry to another. Control algorithm performance is evaluated based on measures such as the fuel required to complete a maneuver and the maximum acceleration required by the controller. Based on this evaluation, the exclusion of the radial axis of control still allows enough control authority to use Linear Quadratic Regulator (LQR) techniques to design a gain matrix of adequate performance over finite maneuvers. Additional simulations are conducted including perturbations and using no radial control inputs. A major conclusion presented is that control inputs along the three axes have significantly different relationships to the governing orbital dynamics that may be exploited using LQR.
Using Arago's spot to monitor optical axis shift in a Petzval refractor.

PubMed

Bruns, Donald G

2017-03-10

Measuring the change in the optical alignment of a camera attached to a telescope is necessary to perform astrometric measurements. Camera movement when the telescope is refocused changes the plate constants, invalidating the calibration. Monitoring the shift in the optical axis requires a stable internal reference source. This is easily implemented in a Petzval refractor by adding an illuminated pinhole and a small obscuration that creates a spot of Arago on the camera. Measurements of the optical axis shift for a commercial telescope are given as an example.
Electrocardiographic consequences of cardiac iron overload in thalassemia major

PubMed Central

Detterich, Jon; Noetzli, Leila; Dorey, Fred; Bar-Cohen, Yaniv; Harmatz, Paul; Coates, Thomas; Wood, John

2011-01-01

Background Iron cardiomyopathy is a leading cause of death in transfusion dependent thalassemia major (TM) patients and MRI (T2*) can recognize preclinical cardiac iron overload, but, is unavailable to many centers. Design and Methods We evaluated the ability of 12-lead electrocardiography to predict cardiac iron loading in TM. 12-lead electrocardiogram and cardiac T2* measurements were performed prospectively, with a detectable cardiac iron cutoff of T2*less than 20 ms. Patients with and without cardiac iron were compared using two-sample statistics and against population norms using age and gender-matched Z-scores. Results 45/78 patients had detectable cardiac iron. Patients having cardiac iron were older and more likely female but had comparable liver iron burdens and serum ferritin. Increased heart rate (HR) and prolonged corrected QT interval (QTc) were present, regardless of cardiac iron status. Repolarization abnormalities were the strongest predictors of cardiac iron, including QT/QTc prolongation, left shift of T-wave axis, and interpretation of ST/T-wave morphology. Recursive partitioning of the data for females using T-axis and HR and for males using QT, HR and T-axis produced algorithms with AUROC’s of 88.3 and 87.1 respectively. Conclusions Bradycardia and repolarization abnormalities on 12-lead electrocardiography were the most specific markers for cardiac iron in thalassemia major. Changes in these variables may be helpful to stratify cardiac risk when cardiac MRI is unavailable. However, diagnostic algorithms need to be vetted on larger and more diverse patient populations and longitudinal studies are necessary to determine reversibility of the observed abnormalities. PMID:22052662
Cytokines and major depression.

PubMed

Schiepers, Olga J G; Wichers, Marieke C; Maes, Michael

2005-02-01

In the research field of psychoneuroimmunology, accumulating evidence has indicated the existence of reciprocal communication pathways between nervous, endocrine and immune systems. In this respect, there has been increasing interest in the putative involvement of the immune system in psychiatric disorders. In the present review, the role of proinflammatory cytokines, such as interleukin (IL)-1, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma, in the aetiology and pathophysiology of major depression, is discussed. The 'cytokine hypothesis of depression' implies that proinflammatory cytokines, acting as neuromodulators, represent the key factor in the (central) mediation of the behavioural, neuroendocrine and neurochemical features of depressive disorders. This view is supported by various findings. Several medical illnesses, which are characterised by chronic inflammatory responses, e.g. rheumatoid arthritis, have been reported to be accompanied by depression. In addition, administration of proinflammatory cytokines, e.g. in cancer or hepatitis C therapies, has been found to induce depressive symptomatology. Administration of proinflammatory cytokines in animals induces 'sickness behaviour', which is a pattern of behavioural alterations that is very similar to the behavioural symptoms of depression in humans. The central action of cytokines may also account for the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity that is frequently observed in depressive disorders, as proinflammatory cytokines may cause HPA axis hyperactivity by disturbing the negative feedback inhibition of circulating corticosteroids (CSs) on the HPA axis. Concerning the deficiency in serotonergic (5-HT) neurotransmission that is concomitant with major depression, cytokines may reduce 5-HT levels by lowering the availability of its precursor tryptophan (TRP) through activation of the TRP-metabolising enzyme indoleamine-2,3-dioxygenase (IDO). Although the central effects of
On the spin-axis dynamics of a Moonless Earth

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

Li, Gongjie; Batygin, Konstantin, E-mail: gli@cfa.harvard.edu

2014-07-20

The variation of a planet's obliquity is influenced by the existence of satellites with a high mass ratio. For instance, Earth's obliquity is stabilized by the Moon and would undergo chaotic variations in the Moon's absence. In turn, such variations can lead to large-scale changes in the atmospheric circulation, rendering spin-axis dynamics a central issue for understanding climate. The relevant quantity for dynamically forced climate change is the rate of chaotic diffusion. Accordingly, here we re-examine the spin-axis evolution of a Moonless Earth within the context of a simplified perturbative framework. We present analytical estimates of the characteristic Lyapunov coefficientmore » as well as the chaotic diffusion rate and demonstrate that even in absence of the Moon, the stochastic change in Earth's obliquity is sufficiently slow to not preclude long-term habitability. Our calculations are consistent with published numerical experiments and illustrate the putative system's underlying dynamical structure in a simple and intuitive manner.« less
The Microbiome-Gut-Behavior Axis: Crosstalk Between the Gut Microbiome and Oligodendrocytes Modulates Behavioral Responses.

PubMed

Ntranos, Achilles; Casaccia, Patrizia

2018-01-01

Environmental and dietary stimuli have always been implicated in brain development and behavioral responses. The gut, being the major portal of communication with the external environment, has recently been brought to the forefront of this interaction with the establishment of a gut-brain axis in health and disease. Moreover, recent breakthroughs in germ-free and antibiotic-treated mice have demonstrated the significant impact of the microbiome in modulating behavioral responses in mice and have established a more specific microbiome-gut-behavior axis. One of the mechanisms by which this axis affects social behavior is by regulating myelination at the prefrontal cortex, an important site for complex cognitive behavior planning and decision-making. The prefrontal cortex exhibits late myelination of its axonal projections that could extend into the third decade of life in humans, which make it susceptible to external influences, such as microbial metabolites. Changes in the gut microbiome were shown to alter the composition of the microbial metabolome affecting highly permeable bioactive compounds, such as p-cresol, which could impair oligodendrocyte differentiation. Dysregulated myelination in the prefrontal cortex is then able to affect behavioral responses in mice, shifting them towards social isolation. The reduced social interactions could then limit microbial exchange, which could otherwise pose a threat to the survival of the existing microbial community in the host and, thus, provide an evolutionary advantage to the specific microbial community. In this review, we will analyze the microbiome-gut-behavior axis, describe the interactions between the gut microbiome and oligodendrocytes and highlight their role in the modulation of social behavior.
Automated cell tracking identifies mechanically oriented cell divisions during Drosophila axis elongation.

PubMed

Wang, Michael F Z; Hunter, Miranda V; Wang, Gang; McFaul, Christopher; Yip, Christopher M; Fernandez-Gonzalez, Rodrigo

2017-04-01

Embryos extend their anterior-posterior (AP) axis in a conserved process known as axis elongation. Drosophila axis elongation occurs in an epithelial monolayer, the germband, and is driven by cell intercalation, cell shape changes, and oriented cell divisions at the posterior germband. Anterior germband cells also divide during axis elongation. We developed image analysis and pattern-recognition methods to track dividing cells from confocal microscopy movies in a generally applicable approach. Mesectoderm cells, forming the ventral midline, divided parallel to the AP axis, while lateral cells displayed a uniform distribution of division orientations. Mesectoderm cells did not intercalate and sustained increased AP strain before cell division. After division, mesectoderm cell density increased along the AP axis, thus relieving strain. We used laser ablation to isolate mesectoderm cells from the influence of other tissues. Uncoupling the mesectoderm from intercalating cells did not affect cell division orientation. Conversely, separating the mesectoderm from the anterior and posterior poles of the embryo resulted in uniformly oriented divisions. Our data suggest that mesectoderm cells align their division angle to reduce strain caused by mechanical forces along the AP axis of the embryo. © 2017. Published by The Company of Biologists Ltd.
Neurodegenerative changes in Alzheimer's disease: a comparative study of manual, semi-automated, and fully automated assessment using MRI

NASA Astrophysics Data System (ADS)

Fritzsche, Klaus H.; Giesel, Frederik L.; Heimann, Tobias; Thomann, Philipp A.; Hahn, Horst K.; Pantel, Johannes; Schröder, Johannes; Essig, Marco; Meinzer, Hans-Peter

2008-03-01

Objective quantification of disease specific neurodegenerative changes can facilitate diagnosis and therapeutic monitoring in several neuropsychiatric disorders. Reproducibility and easy-to-perform assessment are essential to ensure applicability in clinical environments. Aim of this comparative study is the evaluation of a fully automated approach that assesses atrophic changes in Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). 21 healthy volunteers (mean age 66.2), 21 patients with MCI (66.6), and 10 patients with AD (65.1) were enrolled. Subjects underwent extensive neuropsychological testing and MRI was conducted on a 1.5 Tesla clinical scanner. Atrophic changes were measured automatically by a series of image processing steps including state of the art brain mapping techniques. Results were compared with two reference approaches: a manual segmentation of the hippocampal formation and a semi-automated estimation of temporal horn volume, which is based upon interactive selection of two to six landmarks in the ventricular system. All approaches separated controls and AD patients significantly (10 -5 < p < 10 -4) and showed a slight but not significant increase of neurodegeneration for subjects with MCI compared to volunteers. The automated approach correlated significantly with the manual (r = -0.65, p < 10 -6) and semi automated (r = -0.83, p < 10 -13) measurements. It proved high accuracy and at the same time maximized observer independency, time reduction and thus usefulness for clinical routine.
AKT Axis, miR-21, and RECK Play Pivotal Roles in Dihydroartemisinin Killing Malignant Glioma Cells

PubMed Central

Shao, Ying-Ying; Zhang, Tao-Lan; Wu, Lan-Xiang; Zou, He-Cun; Li, Shuang; Huang, Jin; Zhou, Hong-Hao

2017-01-01

Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, is known to play important roles in inhibiting proliferation rate, inducing apoptosis, as well as hindering the metastasis and invasion of glioma cells, but the underlying mechanisms are still unclear so far. In this study, methyl thiazolyl tetrazolium (MTT), colony-forming, wound healing, invasion, and apoptosis assays were performed to investigate the effect of DHA on malignant glioma cells. Results showed that DHA induced apoptosis of malignant glioma cells through Protein Kinase B (AKT) axis, induced death of malignant glioma cells by downregulating miR-21, and inhibited the invasion of malignant glioma cells corresponding with up-regulation of the reversion-inducing-cysteine-rich protein with kazal motifs (RECK). These results revealed that AKT axis, miR-21, and RECK play pivotal roles in DHA killing malignant glioma cells, suggesting that DHA is a potential agent for treating glioma. PMID:28208619
Climate and land use changes effects on soil organic carbon stocks in a Mediterranean semi-natural area.

PubMed

Lozano-García, Beatriz; Muñoz-Rojas, Miriam; Parras-Alcántara, Luis

2017-02-01

A thorough knowledge of the effects of climate and land use changes on the soil carbon pool is critical to planning effective strategies for adaptation and mitigation in future scenarios of global climate and land use change. In this study, we used CarboSOIL model to predict changes in soil organic carbon stocks in a semi-natural area of Southern Spain in three different time horizons (2040, 2070, 2100), considering two general circulation models (BCM2 and ECHAM5) and three IPCC scenarios (A1b, A2, B2). The effects of potential land use changes from natural vegetation (Mediterranean evergreen oak woodland) to agricultural land (olive grove and cereal) on soil organic carbon stocks were also evaluated. Predicted values of SOC contents correlated well those measured (R2 ranging from 0.71 at 0-25cm to 0.97 at 50-75cm) showing the efficiency of the model. Results showed substantial differences among time horizons, climate and land use scenarios and soil depth with larger decreases of soil organic carbon stocks in the long term (2100 time horizon) and particularly in olive groves. The combination of climate and land use scenarios (in particular conversion from current 'dehesa' to olive groves) resulted in yet higher losses of soil organic carbon stocks, e.g. -30, -15 and -33% in the 0-25, 25-50 and 50-75cm sections respectively. This study shows the importance of soil organic carbon stocks assessment under both climate and land use scenarios at different soil sections and point towards possible directions for appropriate land use management in Mediterranean semi natural areas. Copyright © 2016 Elsevier B.V. All rights reserved.
Dynamic transitions in a model of the hypothalamic-pituitary-adrenal axis

NASA Astrophysics Data System (ADS)

Čupić, Željko; Marković, Vladimir M.; Maćešić, Stevan; Stanojević, Ana; Damjanović, Svetozar; Vukojević, Vladana; Kolar-Anić, Ljiljana

2016-03-01

Dynamic properties of a nonlinear five-dimensional stoichiometric model of the hypothalamic-pituitary-adrenal (HPA) axis were systematically investigated. Conditions under which qualitative transitions between dynamic states occur are determined by independently varying the rate constants of all reactions that constitute the model. Bifurcation types were further characterized using continuation algorithms and scale factor methods. Regions of bistability and transitions through supercritical Andronov-Hopf and saddle loop bifurcations were identified. Dynamic state analysis predicts that the HPA axis operates under basal (healthy) physiological conditions close to an Andronov-Hopf bifurcation. Dynamic properties of the stress-control axis have not been characterized experimentally, but modelling suggests that the proximity to a supercritical Andronov-Hopf bifurcation can give the HPA axis both, flexibility to respond to external stimuli and adjust to new conditions and stability, i.e., the capacity to return to the original dynamic state afterwards, which is essential for maintaining homeostasis. The analysis presented here reflects the properties of a low-dimensional model that succinctly describes neurochemical transformations underlying the HPA axis. However, the model accounts correctly for a number of experimentally observed properties of the stress-response axis. We therefore regard that the presented analysis is meaningful, showing how in silico investigations can be used to guide the experimentalists in understanding how the HPA axis activity changes under chronic disease and/or specific pharmacological manipulations.
Analysis of nodal aberration properties in off-axis freeform system design.

PubMed

Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao

2016-08-20

Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design.
Sex differences in early-life programming of the hypothalamic-pituitary-adrenal axis in humans.

PubMed

Gifford, Robert M; Reynolds, Rebecca M

2017-11-01

Increasing evidence supports fetal glucocorticoid exposure with associated altered offspring hypothalamic-pituitary-adrenal (HPA) axis activity as a key mechanism linking early life events with later life disease. Alterations in HPA axis activity are linked to a range of cardiometabolic and psychiatric diseases. As many of these diseases manifest sex differences in presentation we review the evidence for programmed sex-differences in the HPA axis. Available literature suggests vulnerability of the female HPA axis to prenatal stressors with female offspring demonstrating increased HPA axis reactivity. This may be due to changes in placental glucocorticoid metabolism leading to increased fetal glucocorticoid exposure. We discuss the potential consequences of increased vulnerability of the female HPA axis for later life health and consider the underlying mechanisms. Further studies are needed to determine whether sex-differences in early-life programming of the HPA axis represent a pathway underpinning the sex-differences in common cardiometabolic and psychiatric diseases. Copyright © 2017 Elsevier B.V. All rights reserved.
The hypothalamic-pituitary-adrenal axis: what can it tell us about stressors?

PubMed

Armario, Antonio

2006-10-01

The hypothalamic-pituitary-adrenal (HPA) axis is an extremely sensitive physiological system whose activation, with the consequent release of ACTH and glucocorticoids, is triggered by a wide range of psychological experiences and physiological perturbations (stressors). The HPA axis is also activated by a high number of pharmacological agents that markedly differ in structure and function, although the precise mechanisms remain in most cases unknown. Activation of the HPA axis is the consequence of the convergence of stimulatory inputs from different brain regions into the paraventricular nucleus of the hypothalamus (PVN), where the most important ACTH secretagogues (corticotrophin releasing factor, CRF, and arginin-vasopressin, AVP) are formed. Plasma levels of ACTH and corticosterone (the latter under more restricted conditions), are considered as good markers of stress for three main reasons: (a) their plasma levels are proportional to the intensity of emotional and systemic stressors, (b) daily repeated exposure to a stressor usually resulted in reduced ACTH response to the same stressor, that is termed adaptation or habituation; and (c) chronic exposure to stressful situations results in tonic changes in the HPA axis that can be used as indices of the accumulative impact of these situations. These changes can be evaluated under resting conditions (i.e. adrenal weight, CRF and AVP gene expression in the PVN) or after some challenges (administration of CRF, ACTH or dexamethasone) that are classical endocrinological tests. There is also evidence that the activation of the HPA axis may also reflect subtle changes in the characteristics of the stressful situations (unpredictability, lack of control, omission of expected rewards, presence of conspecifics), although this is a topic that requires further studies.
Semi-supervised clustering methods.

PubMed

Bair, Eric

2013-01-01

Cluster analysis methods seek to partition a data set into homogeneous subgroups. It is useful in a wide variety of applications, including document processing and modern genetics. Conventional clustering methods are unsupervised, meaning that there is no outcome variable nor is anything known about the relationship between the observations in the data set. In many situations, however, information about the clusters is available in addition to the values of the features. For example, the cluster labels of some observations may be known, or certain observations may be known to belong to the same cluster. In other cases, one may wish to identify clusters that are associated with a particular outcome variable. This review describes several clustering algorithms (known as "semi-supervised clustering" methods) that can be applied in these situations. The majority of these methods are modifications of the popular k-means clustering method, and several of them will be described in detail. A brief description of some other semi-supervised clustering algorithms is also provided.
Long-term effect of land use change on soil quality: Afforestation and land abandonment in semi-arid Spain

NASA Astrophysics Data System (ADS)

Zethof, Jeroen; Cammeraat, Erik; Nadal-Romero, Estela

2016-04-01

Soils under the Mediterranean climate are vulnerable for degradation, especially after land abandonment. Abandonment is an important factor in the Mediterranean landscape as vegetation regeneration is hampered due to the characteristic semi-arid and sub-humid Mediterranean climate regime. During the past 70 year extensive afforestation projects have been conducted with the aim to protect landscapes and soils against degradation. While large investments are still being made, little is known about the impact of afforestation on soil quality on a longer time scale. During the past decade, there is a growing interest in qualifying and quantifying the carbon storage in soils by such afforestation projects, to get a better understanding of the carbon cycle and look for possibilities to fixate atmospheric CO2 in the soil. It is generally accepted that afforestation projects will increase the soil carbon pool, but data on this process is scarce. Therefore an intensive fieldwork has been carried out in Murcia, southeastern Spain to study the effects of land abandonment and afforestation on soil quality along a chronosequence and included two afforested areas (from the early '70s and 1993). The Pinus halepensis trees were planted in rows, for which the underlying calcrete was broken. Samples were taken to study changes in soil quality (Aggregate stability, Corg, N, P, K, Na), Soil Organic Carbon (SOC) stocks and soil hydraulic properties, such as infiltration and water retention, between the afforestation projects, abandoned agricultural plots of similar age, semi-natural vegetation, cereal crop fields and almond orchards. As the natural vegetation is characterized by a spotted pattern of bare areas and trees, forming so-called "islands of fertility", both bare and vegetation covered sub-sites were sampled. First results showed a positive effect of both land abandonment and afforestation on the soil aggregation. Especially the 40-year-old plots showed underneath trees
Understanding Hydrologic Processes in Semi-Arid Cold Climates

NASA Astrophysics Data System (ADS)

Barber, M. E.; Beutel, M.; Lamb, B.; Watts, R.

2004-12-01

Water shortages destabilize economies and ecosystems. These shortages are caused by complex interactions between climate variability, ecosystem processes, and increased demand from human activities. In the semi-arid region of the northwestern U.S., water availability during drought periods has already reached crisis levels and the problems are expected to intensify as the effects of global climate change and population growth continue to alter the supply and demand patterns. Many of the problems are critical to this region because hydropower, agriculture, navigation, fish and wildlife survival, water supply, tourism, environmental protection, and water-based recreation are vital to state economies and our way of life. In order to assess the spatial and temporal nature of hydrologic responses, consistent and comprehensive long-term data sets are needed. In response to these needs, we would like to propose the Spokane River drainage basin as a long-term hydrologic observatory. The Spokane River basin is located in eastern Washington and northern Idaho and is a tributary of the Columbia River. The watershed consists of several major surface water tributaries as well as natural and man-made lakes and reservoirs. With headwaters beginning in the Rocky Mountains, the drainage area is approximately 6,640 mi2. In addition to providing an excellent study area for examining many conventional water resource problems, the Spokane River watershed also presents a unique opportunity for investigating many of the hydrologic processes found in semi-arid cold climates. Snowfall in the watershed varies spatially between 35 inches near the mouth of the basin to over 112 inches at the headwaters. These varied hydrologic uses provide a unique opportunity to address many common challenges faced by water resource professionals. This broad array of issues encompasses science, engineering, agriculture, social sciences, economics, fisheries, and a host of other disciplines. In addition

Signal Acquisition Using AXIe

NASA Astrophysics Data System (ADS)

Narciso, Steven J.

2011-08-01

An emerging test and measurement standard called AXIe, AdvancedTCA extensions for Instrumentation, is expected to find wide acceptance within the Physics community as it offers many benefits to applications including shock, plasma, particle and nuclear physics. It is expected that many COTS (commercial off-the-shelf) signal conditioning, acquisition and processing modules will become available from a range of different suppliers. AXIe uses AdvancedTCA® as its basis, but then levers test and measurement industry standards such as PXI, IVI, and LXI to facilitate cooperation and plug-and-play interoperability between COTS instrument suppliers. AXIe's large board footprint and power allows high density in a 19" rack, enabling the development of high-performance signal conditioning, analog-to-digital conversion, and data processing, while offering channel count scalability inherent in modular systems. Synchronization between modules is flexible and provided by two triggering structures: a parallel trigger bus, and radially-distributed, time-matched point-to-point trigger lines. Inter-module communication is also provided with an adjacent module local bus allowing data transfer to 600 Gbits/s in each direction, for example between a front-end digitizer and DSP. AXIe allows embedding high performance computing and a range of COTS AdvancedTCA® computer blades are currently available that provide low cost alternatives to the development of custom signal processing modules. The availability of both LAN and PCI Express allow interconnection between modules, as well as industry-standard high-performance data paths to external host computer systems. AXIe delivers a powerful environment for custom module devel opment. As in the case of VXIbus and PXI before it, commercial development kits are expected to be available. This paper will give an overview of the architectural elements of AXIe 1.0, the compatibility model with AdvancedTCA, and signal acquisition performance of many
Off-axis reflective optical apparatus

NASA Technical Reports Server (NTRS)

Ames, Lawrence L. (Inventor); Leary, David F. (Inventor); Mammini, Paul V. (Inventor)

2005-01-01

Embodiments of the present invention are directed to a simple apparatus and a convenient and accurate method of mounting the components to form an off-axis reflective optical apparatus such as a collimator. In one embodiment, an off-axis reflective optical apparatus comprises a mounting block having a ferrule holder support surface and an off-axis reflector support surface which is generally perpendicular to the ferrule holder support surface. An optical reflector is mounted on the off-axis reflector support surface and has a reflected beam centerline. The optical reflector has a conic reflective surface and a conic center. A ferrule holder is mounted on the ferrule holder support surface. The ferrule holder provides a ferrule for coupling to an optical fiber and orienting a fiber tip of the optical fiber along a fiber axis toward the optical reflector. The fiber axis is nonparallel to the reflected beam centerline. Prior to mounting the optical reflector to the off-axis reflector support surface and prior to mounting the ferrule holder to the ferrule holder support surface, the optical reflector is movable on the off-axis reflector surface and the ferrule holder is movable on the ferrule holder support surface to align the conic center of the optical reflector with respect to the fiber tip of the optical fiber, and the apparatus has at least one of the following features: (1) the optical reflector is movable on the off-axis reflector support surface to adjust a focus of the fiber tip with respect to the optical reflector, and (2) the ferrule holder is movable on the ferrule holder support surface to adjust the focus of the fiber tip with respect to the optical reflector.
Gut Microbiota-brain Axis

PubMed Central

Wang, Hong-Xing; Wang, Yu-Ping

2016-01-01

Objective: To systematically review the updated information about the gut microbiota-brain axis. Data Sources: All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of “gut microbiota”, “gut-brain axis”, and “neuroscience”. Study Selection: All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of study design. Results: It is well-recognized that gut microbiota affects the brain's physiological, behavioral, and cognitive functions although its precise mechanism has not yet been fully understood. Gut microbiota-brain axis may include gut microbiota and their metabolic products, enteric nervous system, sympathetic and parasympathetic branches within the autonomic nervous system, neural-immune system, neuroendocrine system, and central nervous system. Moreover, there may be five communication routes between gut microbiota and brain, including the gut-brain's neural network, neuroendocrine-hypothalamic-pituitary-adrenal axis, gut immune system, some neurotransmitters and neural regulators synthesized by gut bacteria, and barrier paths including intestinal mucosal barrier and blood-brain barrier. The microbiome is used to define the composition and functional characteristics of gut microbiota, and metagenomics is an appropriate technique to characterize gut microbiota. Conclusions: Gut microbiota-brain axis refers to a bidirectional information network between the gut microbiota and the brain, which may provide a new way to protect the brain in the near future. PMID:27647198
Does the GH/IGF-1 axis contribute to skeletal sexual dimorphism? Evidence from mouse studies.

PubMed

Liu, Zhongbo; Mohan, Subburaman; Yakar, Shoshana

2016-04-01

The contribution of the gonadotropic axis to skeletal sexual dimorphism (SSD) was clarified in recent years. Studies with animal models of estrogen receptor (ER) or androgen receptor (AR) null mice, as well as mice with bone cell-specific ablation of ER or AR, revealed that both hormones play major roles in skeletal acquisition, and that estrogen regulates skeletal accrual in both sexes. The growth hormone (GH) and its downstream effector, the insulin-like growth factor-1 (IGF-1) are also major determinants of peak bone mass during puberty and young adulthood, and play important roles in maintaining bone integrity during aging. A few studies in both humans and animal models suggest that in addition to the differences in sex steroid actions on bone, sex-specific effects of GH and IGF-1 play essential roles in SSD. However, the contributions of the somatotropic (GH/IGF-1) axis to SSD are controversial and data is difficult to interpret. GH/IGF-1 are pleotropic hormones that act in an endocrine and autocrine/paracrine fashion on multiple tissues, affecting body composition as well as metabolism. Thus, understanding the contribution of the somatotropic axis to SSD requires the use of mouse models that will differentiate between these two modes of action. Elucidation of the relative contribution of GH/IGF-1 axis to SSD is significant because GH is approved for the treatment of normal children with short stature and children with congenital growth disorders. Thus, if the GH/IGF-1 axis determines SSD, treatment with GH may be tailored according to sex. In the following review, we give an overview of the roles of sex steroids in determining SSD and how they may interact with the GH/IGF-1 axis in bone. We summarize several mouse models with impaired somatotropic axis and speculate on the possible contribution of that axis to SSD. Copyright © 2015 Elsevier Ltd. All rights reserved.
Climate change impact assessment on hydrology of a small watershed using semi-distributed model

NASA Astrophysics Data System (ADS)

Pandey, Brij Kishor; Gosain, A. K.; Paul, George; Khare, Deepak

2017-07-01

This study is an attempt to quantify the impact of climate change on the hydrology of Armur watershed in Godavari river basin, India. A GIS-based semi-distributed hydrological model, soil and water assessment tool (SWAT) has been employed to estimate the water balance components on the basis of unique combinations of slope, soil and land cover classes for the base line (1961-1990) and future climate scenarios (2071-2100). Sensitivity analysis of the model has been performed to identify the most critical parameters of the watershed. Average monthly calibration (1987-1994) and validation (1995-2000) have been performed using the observed discharge data. Coefficient of determination (R2), Nash-Sutcliffe efficiency (ENS) and root mean square error (RMSE) were used to evaluate the model performance. Calibrated SWAT setup has been used to evaluate the changes in water balance components of future projection over the study area. HadRM3, a regional climatic data, have been used as input of the hydrological model for climate change impact studies. In results, it was found that changes in average annual temperature (+3.25 °C), average annual rainfall (+28 %), evapotranspiration (28 %) and water yield (49 %) increased for GHG scenarios with respect to the base line scenario.
Hair cortisol as a marker of hypothalamic-pituitary-adrenal Axis activity in female patients with major depressive disorder.

PubMed

Pochigaeva, Ksenia; Druzhkova, Tatiana; Yakovlev, Alexander; Onufriev, Mikhail; Grishkina, Maria; Chepelev, Aleksey; Guekht, Alla; Gulyaeva, Natalia

2017-04-01

Hair cortisol is regarded as a promising marker of hypothalamic-pituitary-adrenal axis (HPAA) activity alterations due to stress, somatic and mental health conditions. Hair cortisol was previously reported to be elevated in patients with depression, however the data related to remission and recurrent depressive episodes are different. In this study, levels of hair cortisol were assessed in female patients with major depressive disorder (MDD) and the validity of hair cortisol as a marker of HPAA activity in this condition was evaluated. Hair cortisol was measured in 1 cm hair segments of 21 female patients with MDD and 22 female age-matched controls using enzyme-immunoassay analysis. Concurrently, serum cortisol was assessed and psychological status was evaluated using 17-item Hamilton Depression Rating Scale (HAMD-17), Beck Depression Inventory (BDI) and the Spielberger state trait anxiety inventory (STAI). The levels of hair cortisol were significantly lower in the MDD group, while serum cortisol levels were significantly higher in patients, as compared with controls. A significant negative correlation was found between HAMD-17 scores and hair cortisol. Decreased hair cortisol found in female patients with MDD as compared to controls suggests downregulation of HPAA activity during the preceding month. Further studies are needed to investigate the profiles of hair cortisol at different stages of depressive disorder to establish this parameter as a handy clinical tool.
Reliability of Semi-Automated Segmentations in Glioblastoma.

PubMed

Huber, T; Alber, G; Bette, S; Boeckh-Behrens, T; Gempt, J; Ringel, F; Alberts, E; Zimmer, C; Bauer, J S

2017-06-01

In glioblastoma, quantitative volumetric measurements of contrast-enhancing or fluid-attenuated inversion recovery (FLAIR) hyperintense tumor compartments are needed for an objective assessment of therapy response. The aim of this study was to evaluate the reliability of a semi-automated, region-growing segmentation tool for determining tumor volume in patients with glioblastoma among different users of the software. A total of 320 segmentations of tumor-associated FLAIR changes and contrast-enhancing tumor tissue were performed by different raters (neuroradiologists, medical students, and volunteers). All patients underwent high-resolution magnetic resonance imaging including a 3D-FLAIR and a 3D-MPRage sequence. Segmentations were done using a semi-automated, region-growing segmentation tool. Intra- and inter-rater-reliability were addressed by intra-class-correlation (ICC). Root-mean-square error (RMSE) was used to determine the precision error. Dice score was calculated to measure the overlap between segmentations. Semi-automated segmentation showed a high ICC (> 0.985) for all groups indicating an excellent intra- and inter-rater-reliability. Significant smaller precision errors and higher Dice scores were observed for FLAIR segmentations compared with segmentations of contrast-enhancement. Single rater segmentations showed the lowest RMSE for FLAIR of 3.3 % (MPRage: 8.2 %). Both, single raters and neuroradiologists had the lowest precision error for longitudinal evaluation of FLAIR changes. Semi-automated volumetry of glioblastoma was reliably performed by all groups of raters, even without neuroradiologic expertise. Interestingly, segmentations of tumor-associated FLAIR changes were more reliable than segmentations of contrast enhancement. In longitudinal evaluations, an experienced rater can detect progressive FLAIR changes of less than 15 % reliably in a quantitative way which could help to detect progressive disease earlier.
Field dependence of the electron drift velocity along the hexagonal axis of 4H-SiC

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

Ivanov, P. A., E-mail: Pavel.Ivanov@mail.ioffe.ru; Potapov, A. S.; Samsonova, T. P.

The forward current–voltage characteristics of mesa-epitaxial 4H-SiC Schottky diodes are measured in high electric fields (up to 4 × 10{sup 5} V/cm) in the n-type base region. A semi-empirical formula for the field dependence of the electron drift velocity in 4H-SiC along the hexagonal axis of the crystal is derived. It is shown that the saturated drift velocity is (1.55 ± 0.05) × 10{sup 7} cm/s in electric fields higher than 2 × 10{sup 5} V/cm.
Three-axis lever actuator with flexure hinges for an optical disk system

NASA Astrophysics Data System (ADS)

Han, Chang-Soo; Kim, Soo-Hyun

2002-10-01

A three-axis lever actuator with a flexure hinge has been designed and fabricated. This actuator is driven by electromagnetic force based on a coil-magnet system and can be used as a high precision actuator and, especially as a pickup head actuator in optical disks. High precision and low sensitivity to external vibration are the major advantages of this lever actuator. An analysis model was found and compared to the finite element method. Dynamic characteristics of the three-axis lever actuator were measured. The results are in very close agreement to those predicted by the model and finite element analysis.
The distribution of near-axis seamounts at intermediate spreading ridges

NASA Astrophysics Data System (ADS)

Howell, J. K.; Bohnenstiehl, D. R.; White, S. M.; Supak, S. K.

2008-12-01

The ridge axes along the intermediate-spreading rate Galapagos Spreading Center (GSC, 46-56 mm/yr) and South East Indian Ridge (SEIR, 72-76 mm/yr) vary from rifted axial valleys to inflated axial highs independent of spreading rate. The delivery and storage of melt is believed to control axial morphology, with axial highs typically observed in areas underlain by a shallow melt lens and axial valleys in areas without a significant melt lens [e.g., Baran et al., 2005 G-cubed; Detrick et al. 2002 G-cubed]. To investigate a possible correlation between the style of seafloor volcanism and axial morphology, a closed contour algorithm is used to identify near axis (2.5km off axis) semi-circular seamounts of heights greater than 20m from shipboard multibeam bathymetry. In areas characterized by an axial high, more seamounts are formed at the ends of the segments than in the center. This is consistent with observations at fast-spreading ridges and suggests a tendency of lavas to erupt at lower effusion rates near second-order segment boundaries. Segments with a rift valley along the GSC show the opposite trend, with more seamounts at the center of second-order segments. Both patterns however are observed along SEIR segments with rift valleys where magma supply may be reflected in size and not their abundance.
How does the brain deal with cumulative stress? A review with focus on developmental stress, HPA axis function and hippocampal structure in humans.

PubMed

Frodl, Thomas; O'Keane, Veronica

2013-04-01

There is evidence that excessive stress exposure of the brain, mediated through the neurotoxic effects of cortisol and possibly neuroinflammation, causes damage to brain structure and function: the glucocorticoid cascade hypothesis. Functional changes of hypothalamic-pituitary-adrenal (HPA) axis as well as alterations in brain structures like the hippocampus have been consistently reported in major depression. However, there has not been a lot of emphasis on bringing findings from studies on early childhood stress, HPA axis functioning and hippocampal imaging together. This is the subject for this systematic review of the literature on how developmental stress, specifically childhood maltreatment, may impact on HPA axis function and hippocampal structure. We will also review the literature on the relationship between HPA axis function and hippocampal volume in healthy, depressed and other disease states. There is evidence that prenatal stress and childhood maltreatment is associated with an abnormally developing HPA system, as well as hippocampal volume reduction. Smaller hippocampal volumes are associated with increased cortisol secretion during the day. We conclude that a model integrating childhood maltreatment, cortisol abnormalities and hippocampal volume may need to take other factors into account, such as temperament, genetics or the presence of depression; to provide a cohesive explanation of all the findings. Finally, we have to conclude that the cascade hypothesis, mainly based on preclinical studies, has not been translated enough into humans. While there is evidence that early life maltreatment results in structural hippocampal changes and these are in turn more prominent in subjects with higher continuous cortisol secretion it is less clear which role early life maltreatment plays in HPA axis alteration. Copyright © 2012 Elsevier Inc. All rights reserved.
Molar axis estimation from computed tomography images.

PubMed

Dongxia Zhang; Yangzhou Gan; Zeyang Xia; Xinwen Zhou; Shoubin Liu; Jing Xiong; Guanglin Li

2016-08-01

Estimation of tooth axis is needed for some clinical dental treatment. Existing methods require to segment the tooth volume from Computed Tomography (CT) images, and then estimate the axis from the tooth volume. However, they may fail during estimating molar axis due to that the tooth segmentation from CT images is challenging and current segmentation methods may get poor segmentation results especially for these molars with angle which will result in the failure of axis estimation. To resolve this problem, this paper proposes a new method for molar axis estimation from CT images. The key innovation point is that: instead of estimating the 3D axis of each molar from the segmented volume, the method estimates the 3D axis from two projection images. The method includes three steps. (1) The 3D images of each molar are projected to two 2D image planes. (2) The molar contour are segmented and the contour's 2D axis are extracted in each 2D projection image. Principal Component Analysis (PCA) and a modified symmetry axis detection algorithm are employed to extract the 2D axis from the segmented molar contour. (3) A 3D molar axis is obtained by combining the two 2D axes. Experimental results verified that the proposed method was effective to estimate the axis of molar from CT images.
An assessment of HIV treatment outcomes among utilizers of semi-mobile clinics in rural Kenya.

PubMed

Gorman, Sara E; Martinez, Jose M; Olson, Jennifer

2015-01-01

HIV/AIDS is a major cause of morbidity and mortality in Africa, and rates of retention in treatment are low. Some research has shown that mobile clinics are effective in connecting people in rural areas with health care. We compared HIV outcomes between HIV-positive patients who chose to access treatment from a regional hospital to those who chose care in one of four semi-mobile clinics closer to where they live. The subjects for this analysis were HIV-positive residents in West Pokot accessing care at one of four semi-mobile sites (Kabichbich, Chepareria, Kacheliba, and Sigor) or at the regional hospital in Kapenguria. We examined four outcome variables between the two groups: (1) retention in HIV treatment, (2) change in CD4 count, (3) adherence to ARVs, and (4) deaths. The patients who chose semi-mobile clinic care were less well educated, poorer, and sicker than those who chose to continue care in the regional hospital. There were no statistically significant differences between the groups in any of the four outcome measures. Although the population of patients attending semi-mobile clinics was on average poorer and sicker than those attending the hospital, their outcomes were similar. Care at the semi-mobile clinics did not result in significantly different outcomes from care in the district hospital. This program showed that semi-mobile clinics are a viable alternative to hospital care for very ill, isolated populations, but further measures must be taken to improve retention and adherence in these settings.
Semi-automatic tracking, smoothing and segmentation of hyoid bone motion from videofluoroscopic swallowing study.

PubMed

Kim, Won-Seok; Zeng, Pengcheng; Shi, Jian Qing; Lee, Youngjo; Paik, Nam-Jong

2017-01-01

Motion analysis of the hyoid bone via videofluoroscopic study has been used in clinical research, but the classical manual tracking method is generally labor intensive and time consuming. Although some automatic tracking methods have been developed, masked points could not be tracked and smoothing and segmentation, which are necessary for functional motion analysis prior to registration, were not provided by the previous software. We developed software to track the hyoid bone motion semi-automatically. It works even in the situation where the hyoid bone is masked by the mandible and has been validated in dysphagia patients with stroke. In addition, we added the function of semi-automatic smoothing and segmentation. A total of 30 patients' data were used to develop the software, and data collected from 17 patients were used for validation, of which the trajectories of 8 patients were partly masked. Pearson correlation coefficients between the manual and automatic tracking are high and statistically significant (0.942 to 0.991, P-value<0.0001). Relative errors between automatic tracking and manual tracking in terms of the x-axis, y-axis and 2D range of hyoid bone excursion range from 3.3% to 9.2%. We also developed an automatic method to segment each hyoid bone trajectory into four phases (elevation phase, anterior movement phase, descending phase and returning phase). The semi-automatic hyoid bone tracking from VFSS data by our software is valid compared to the conventional manual tracking method. In addition, the ability of automatic indication to switch the automatic mode to manual mode in extreme cases and calibration without attaching the radiopaque object is convenient and useful for users. Semi-automatic smoothing and segmentation provide further information for functional motion analysis which is beneficial to further statistical analysis such as functional classification and prognostication for dysphagia. Therefore, this software could provide the
Can Recent Global Changes Explain the Dramatic Range Contraction of an Endangered Semi-Aquatic Mammal Species in the French Pyrenees?

PubMed

Charbonnel, Anaïs; Laffaille, Pascal; Biffi, Marjorie; Blanc, Frédéric; Maire, Anthony; Némoz, Mélanie; Sanchez-Perez, José Miguel; Sauvage, Sabine; Buisson, Laëtitia

2016-01-01

Species distribution models (SDMs) are the main tool to predict global change impacts on species ranges. Climate change alone is frequently considered, but in freshwater ecosystems, hydrology is a key driver of the ecology of aquatic species. At large scale, hydrology is however rarely accounted for, owing to the lack of detailed stream flow data. In this study, we developed an integrated modelling approach to simulate stream flow using the hydrological Soil and Water Assessment Tool (SWAT). Simulated stream flow was subsequently included as an input variable in SDMs along with topographic, hydrographic, climatic and land-cover descriptors. SDMs were applied to two temporally-distinct surveys of the distribution of the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees: a historical one conducted from 1985 to 1992 and a current one carried out between 2011 and 2013. The model calibrated on historical data was also forecasted onto the current period to assess its ability to describe the distributional change of the Pyrenean desman that has been modelled in the recent years. First, we found that hydrological and climatic variables were the ones influencing the most the distribution of this species for both periods, emphasizing the importance of taking into account hydrology when SDMs are applied to aquatic species. Secondly, our results highlighted a strong range contraction of the Pyrenean desman in the French Pyrenees over the last 25 years. Given that this range contraction was under-estimated when the historical model was forecasted onto current conditions, this finding suggests that other drivers may be interacting with climate, hydrology and land-use changes. Our results imply major concerns for the conservation of this endemic semi-aquatic mammal since changes in climate and hydrology are expected to become more intense in the future.
Can Recent Global Changes Explain the Dramatic Range Contraction of an Endangered Semi-Aquatic Mammal Species in the French Pyrenees?

PubMed Central

Charbonnel, Anaïs; Laffaille, Pascal; Biffi, Marjorie; Blanc, Frédéric; Maire, Anthony; Némoz, Mélanie; Sanchez-Perez, José Miguel; Sauvage, Sabine

2016-01-01

Species distribution models (SDMs) are the main tool to predict global change impacts on species ranges. Climate change alone is frequently considered, but in freshwater ecosystems, hydrology is a key driver of the ecology of aquatic species. At large scale, hydrology is however rarely accounted for, owing to the lack of detailed stream flow data. In this study, we developed an integrated modelling approach to simulate stream flow using the hydrological Soil and Water Assessment Tool (SWAT). Simulated stream flow was subsequently included as an input variable in SDMs along with topographic, hydrographic, climatic and land-cover descriptors. SDMs were applied to two temporally-distinct surveys of the distribution of the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees: a historical one conducted from 1985 to 1992 and a current one carried out between 2011 and 2013. The model calibrated on historical data was also forecasted onto the current period to assess its ability to describe the distributional change of the Pyrenean desman that has been modelled in the recent years. First, we found that hydrological and climatic variables were the ones influencing the most the distribution of this species for both periods, emphasizing the importance of taking into account hydrology when SDMs are applied to aquatic species. Secondly, our results highlighted a strong range contraction of the Pyrenean desman in the French Pyrenees over the last 25 years. Given that this range contraction was under-estimated when the historical model was forecasted onto current conditions, this finding suggests that other drivers may be interacting with climate, hydrology and land-use changes. Our results imply major concerns for the conservation of this endemic semi-aquatic mammal since changes in climate and hydrology are expected to become more intense in the future. PMID:27467269
Changes in Tilt of Mars Axis

NASA Image and Video Library

2011-11-21

Modern-day Mars experiences cyclical changes in climate and, consequently, ice distribution. Unlike Earth, the obliquity or tilt of Mars changes substantially on timescales of hundreds of thousands to millions of years.
In Search of HPA Axis Dysregulation in Child and Adolescent Depression

ERIC Educational Resources Information Center

Guerry, John D.; Hastings, Paul D.

2011-01-01

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis in adults with major depressive disorder is among the most consistent and robust biological findings in psychiatry. Given the importance of the adolescent transition to the development and recurrence of depressive phenomena over the lifespan, it is important to have an integrative…
Associations in the Course of Personality Disorders and Axis I Disorders Over Time

PubMed Central

Shea, M. Tracie; Yen, Shirley; Pagano, Maria E.; Morey, Leslie C.; McGlashan, Thomas H.; Grilo, Carlos M.; Sanislow, Charles A.; Stout, Robert L.; Skodol, Andrew E.; Gunderson, John G.; Bender, Donna S.; Zanarini, Mary C.

2012-01-01

In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive–compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive–compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders. PMID:15535783
Microbiota-gut-brain axis and the central nervous system.

PubMed

Zhu, Xiqun; Han, Yong; Du, Jing; Liu, Renzhong; Jin, Ketao; Yi, Wei

2017-08-08

The gut and brain form the gut-brain axis through bidirectional nervous, endocrine, and immune communications. Changes in one of the organs will affect the other organs. Disorders in the composition and quantity of gut microorganisms can affect both the enteric nervous system and the central nervous system (CNS), thereby indicating the existence of a microbiota-gut-brain axis. Due to the intricate interactions between the gut and the brain, gut symbiotic microorganisms are closely associated with various CNS diseases, such as Parkinson's disease, Alzheimer's disease, schizophrenia, and multiple sclerosis. In this paper, we will review the latest advances of studies on the correlation between gut microorganisms and CNS functions & diseases.

Multi-Axis Test Facility

NASA Image and Video Library

1959-11-01

Multi-Axis Test Facility, Space Progress Report, November 1, 1959: The Multi Axis Space Test Inertia Facility [MASTIF], informally referred to as the Gimbal Rig, was installed inside the Altitude Wind Tunnel. The rig, which spun on three axis simultaneously, was used to train the Mercury astronauts on how to bring a spinning spacecraft under control and to determine the effects of rapid spinning on the astronaut's eyesight and psyche. Small gaseous nitrogen jets were operated by the pilot to gain control of the rig after it had been set in motion. Part 1 shows pilot Joe Algranti in the rig as it rotates over one, two, and three axis. It also has overall views of the test set-up with researchers and technicians on the test platform. Part 2 shows Algranti being secured in the rig prior to the test. The rig is set in motion and the pilot slowly brings it under control. The Mercury astronauts trained on the MASTIF in early spring of 1960.
14 CFR 21.97 - Approval of major changes in type design.

Code of Federal Regulations, 2014 CFR

2014-01-01

... must— (1) Provide substantiating data and necessary descriptive data for inclusion in the type design... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Approval of major changes in type design... TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Changes to Type Certificates § 21.97...
14 CFR 21.97 - Approval of major changes in type design.

Code of Federal Regulations, 2013 CFR

2013-01-01

.... (a) An applicant for approval of a major change in type design must— (1) Provide substantiating data and necessary descriptive data for inclusion in the type design; (2) Show that the changed product... the necessary descriptive data for inclusion in the type design the other configurations of the same...
Defining Global Gene Expression Changes of the Hypothalamic-Pituitary-Gonadal Axis in Female sGnRH-Antisense Transgenic Common Carp (Cyprinus carpio)

PubMed Central

Xu, Jing; Huang, Wei; Zhong, Chengrong; Luo, Daji; Li, Shuangfei; Zhu, Zuoyan; Hu, Wei

2011-01-01

Background The hypothalamic-pituitary-gonadal (HPG) axis is critical in the development and regulation of reproduction in fish. The inhibition of neuropeptide gonadotropin-releasing hormone (GnRH) expression may diminish or severely hamper gonadal development due to it being the key regulator of the axis, and then provide a model for the comprehensive study of the expression patterns of genes with respect to the fish reproductive system. Methodology/Principal Findings In a previous study we injected 342 fertilized eggs from the common carp (Cyprinus carpio) with a gene construct that expressed antisense sGnRH. Four years later, we found a total of 38 transgenic fish with abnormal or missing gonads. From this group we selected the 12 sterile females with abnormal ovaries in which we combined suppression subtractive hybridization (SSH) and cDNA microarray analysis to define changes in gene expression of the HPG axis in the present study. As a result, nine, 28, and 212 genes were separately identified as being differentially expressed in hypothalamus, pituitary, and ovary, of which 87 genes were novel. The number of down- and up-regulated genes was five and four (hypothalamus), 16 and 12 (pituitary), 119 and 93 (ovary), respectively. Functional analyses showed that these genes involved in several biological processes, such as biosynthesis, organogenesis, metabolism pathways, immune systems, transport links, and apoptosis. Within these categories, significant genes for neuropeptides, gonadotropins, metabolic, oogenesis and inflammatory factors were identified. Conclusions/Significance This study indicated the progressive scaling-up effect of hypothalamic sGnRH antisense on the pituitary and ovary receptors of female carp and provided comprehensive data with respect to global changes in gene expression throughout the HPG signaling pathway, contributing towards improving our understanding of the molecular mechanisms and regulative pathways in the reproductive system of
Design of Off-Axis PIAACMC Mirrors

NASA Technical Reports Server (NTRS)

Pluzhnik, Eugene; Guyon, Olivier; Belikov, Ruslan; Kern, Brian; Bendek, Eduardo

2015-01-01

The Phase-Induced Amplitude Apodization Complex Mask Coronagraph (PIAACMC) provides an efficient way to control diffraction propagation effects caused by the central obstruction/segmented mirrors of the telescope. PIAACMC can be optimized in a way that takes into account both chromatic diffraction effects caused by the telescope obstructed aperture and tip/tilt sensitivity of the coronagraph. As a result, unlike classic PIAA, the PIAACMC mirror shapes are often slightly asymmetric even for an on-axis configuration and require more care in calculating off-axis shapes when an off-axis configuration is preferred. A method to design off-axis PIAA mirror shapes given an on-axis mirror design is presented. The algorithm is based on geometrical ray tracing and is able to calculate off-axis PIAA mirror shapes for an arbitrary geometry of the input and output beams. The method is demonstrated using the third generation PIAACMC design for WFIRST-AFTA (Wide Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets) telescope. Geometrical optics design issues related to the off-axis diffraction propagation effects are also discussed.
Navigation Guidelines for Orbital Formation Flying Missions

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell

2003-01-01

Some simple guidelines based on the accuracy in determining a satellite formation's semi-major axis differences are useful in making preliminary assessments of the navigation accuracy needed to support such missions. These guidelines are valid for any elliptical orbit, regardless of eccentricity. Although maneuvers required for formation establishment, reconfiguration, and station-keeping require accurate prediction of the state estimate to the maneuver time, and hence are directly affected by errors in all the orbital elements, experience has shown that determination of orbit plane orientation and orbit shape to acceptable levels is less challenging than the determination of orbital period or semi-major axis. Furthermore, any differences among the member's semi-major axis are undesirable for a satellite formation, since it will lead to differential along-track drift due to period differences. Since inevitable navigation errors prevent these differences from ever being zero, one may use the guidelines this paper presents to determine how much drift will result from a given relative navigation accuracy, or vice versa. Since the guidelines do not account for non-two-body perturbations, they may be viewed as useful preliminary design tools, rather than as the basis for mission navigation requirements, which should be based on detailed analysis of the mission configuration, including all relevant sources of uncertainty.
Atmospheric density determination using high-accuracy satellite GPS data

NASA Astrophysics Data System (ADS)

Tingling, R.; Miao, J.; Liu, S.

2017-12-01

Atmospheric drag is the main error source in the orbit determination and prediction of low Earth orbit (LEO) satellites, however, empirical models which are used to account for atmosphere often exhibit density errors around 15 30%. Atmospheric density determination thus become an important topic for atmospheric researchers. Based on the relation between atmospheric drag force and the decay of orbit semi-major axis, we derived atmospheric density along the trajectory of CHAMP with its Rapid Science Orbit (RSO) data. Three primary parameters are calculated, including the ratio of cross sectional area to mass, drag coefficient, and the decay of semi-major axis caused by atmospheric drag. We also analyzed the source of error and made a comparison between GPS-derived and reference density. Result on 2 Dec 2008 shows that the mean error of GPS-derived density can decrease from 29.21% to 9.20% when time span adopted on the process of computation increase from 10min to 50min. Result for the whole December indicates that when the time span meet the condition that the amplitude of the decay of semi-major axis is much greater than its standard deviation, then density precision of 10% can be achieved.
Determination of the number of Vertical Axis Wind Turbine blades based on power spectrum

NASA Astrophysics Data System (ADS)

Fedak, Waldemar; Anweiler, Stanisław; Gancarski, Wojciech; Ulbrich, Roman

2017-10-01

Technology of wind exploitation has been applied widely all over the world and has already reached the level in which manufacturers want to maximize the yield with the minimum investment outlays. The main objective of this paper is the determination of the optimal number of blades in the Cup-Bladed Vertical Axis Wind Turbine. Optimizing the size of the Vertical Axis Wind Turbine allows the reduction of costs. The maximum power of the rotor is selected as the performance target. The optimum number of Vertical Axis Wind Turbine blades evaluation is based on analysis of a single blade simulation and its superposition for the whole rotor. The simulation of working blade was done in MatLab environment. Power spectrum graphs were prepared and compared throughout superposition of individual blades in the Vertical Axis Wind Turbine rotor. The major result of this research is the Vertical Axis Wind Turbine power characteristic. On the basis of the analysis of the power spectra, optimum number of the blades was specified for the analysed rotor. Power spectrum analysis of wind turbine enabled the specification of the optimal number of blades, and can be used regarding investment outlays and power output of the Vertical Axis Wind Turbine.
Impact of personality psychopathology on outcome in short-term cognitive-behavioral therapy for Axis I disorders.

PubMed

Bédard, Mathieu; Russell, Jennifer J; Myhr, Gail

2015-12-15

Cognitive behavioral therapy (CBT) is efficacious for many Axis I disorders, though its effectiveness in the real world, for patients with Axis II comorbidity is less well known. This study examines the effectiveness of CBT for Axis I disorders in three groups of patients: those with personality disorders, those with personality disorder traits and those with no Axis II pathology. Consecutive referrals of patients with non-psychotic Axis I disorders were assessed for short-term CBT in a University Teaching Unit. While the acceptance rate was lower for individuals with personality disorders, there were no group differences in dropout rates. Of those who completed therapy (mean number of sessions=17.8, SD=11.2), those in the Personality Disorders group (n=45) had 4 sessions more on average than the Personality Disorder Traits group (n=42) or the No Axis II Group (n=266). All 3 groups were equally successful, whether the outcome was therapist opinion of success, the clinical global impression, or the reliable change index based on patient-reported symptom change. Intent to treat analysis results paralleled those of the completer analysis. Our findings indicate that the presence of a personality disorder does not negatively impact therapy adherence or success in short-term CBT for an Axis I disorder. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
14 CFR 21.97 - Approval of major changes in type design.

Code of Federal Regulations, 2011 CFR

2011-01-01

... necessary descriptive data for inclusion in the type design the other configurations of the same engine type... for approval of a major change in type design must— (1) Provide substantiating data and necessary descriptive data for inclusion in the type design; (2) Show that the changed product complies with the...
76 FR 38552 - Amendments to Regulations Regarding Major Life-Changing Events Affecting Income-Related Monthly...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-01

... to Regulations Regarding Major Life-Changing Events Affecting Income-Related Monthly Adjustment.... SUMMARY: This final rule adopts, without change, the interim final rule with request for comments we... consider major life-changing events for the Medicare Part B income- related monthly adjustment amount...
Endocrine changes in histiocytosis of the hypothalamic-pituitary axis.

PubMed

Toro Galván, Silvia; Planas Vilaseca, Alejandra; Michalopoulou Alevras, Theodora; Torres Díaz, Alberto; Suárez Balaguer, Javier; Villabona Artero, Carles

2015-02-01

Histiocytosis is characterized by proliferation of cells from the mononuclear phagocyte system, and may be divided into Langerhans cell histiocytosis (LCH) and non-Langerhans cell histiocytosis (including Erdheim-Chester disease [ECD]). While diabetes insipidus (DI) is the most common hypothalamic-pituitary consequence, anterior pituitary deficiencies are less known. This study analyzed the frequency and progression of pituitary hormone deficiencies and the radiographic findings in 9 patients (7 with LCH and 2 with ECD) with hypothalamic-pituitary (HP) axis. Eighty-nine percent of patients had DI (62% at diagnosis), and 78% had one or more anterior pituitary deficiencies (71% at diagnosis). HP involvement is relatively common in patients diagnosed with histiocytosis and hormone deficiencies may be present at diagnosis or appear gradually during the course of disease. Regular monitoring of these patients is recommended. Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.
Aeroelastically coupled blades for vertical axis wind turbines

DOEpatents

Paquette, Joshua; Barone, Matthew F.

2016-02-23

Various technologies described herein pertain to a vertical axis wind turbine blade configured to rotate about a rotation axis. The vertical axis wind turbine blade includes at least an attachment segment, a rear swept segment, and optionally, a forward swept segment. The attachment segment is contiguous with the forward swept segment, and the forward swept segment is contiguous with the rear swept segment. The attachment segment includes a first portion of a centroid axis, the forward swept segment includes a second portion of the centroid axis, and the rear swept segment includes a third portion of the centroid axis. The second portion of the centroid axis is angularly displaced ahead of the first portion of the centroid axis and the third portion of the centroid axis is angularly displaced behind the first portion of the centroid axis in the direction of rotation about the rotation axis.
Morphological changes in the pituitary-adrenocortical axis in natives of La Paz

NASA Astrophysics Data System (ADS)

Gosney, John; Heath, Donald; Williams, David; Rios-Dalenz, Jaime

1991-03-01

Increased activity of the hypothalamic-pituitary-adrenocortical axis is part of the response to the stress of initial exposure to hypoxia, but there is evidence to suggest that it persists after homeostatic stability has been regained and acclimatization achieved. The adrenal glands of five lifelong residents of La Paz, Bolivia, who had lived at altitudes in the range 3600 3800 m, were significantly larger than those in age-matched controls from sea level (15.3g vs 10.4g; P<0.001) and appeared hyperplastic. The pituitary glands of the highlanders were not significantly different in size from those of the controls (0.67 g vs 0.51 g), but contained larger populations of corticotrophs expressed in terms of the total cell population of their anterior lobes (25.6% vs 19.4%; P<0.001). In conjunction with other studies of this endocrine axis in man and animals exposed to a hypoxic environment, these data suggest that greater amounts of adrenocorticotrophic hormone (ACTH) are required to maintain normal adrenocortical function under such circumstances, probably as a result of hypoxic inhibition of adrenocortical sensitivity to stimulation. Physiological hyperplasia of the adrenal cortex may be common in people living at high altitude.
Semi-supervised clustering methods

PubMed Central

Bair, Eric

2013-01-01

Cluster analysis methods seek to partition a data set into homogeneous subgroups. It is useful in a wide variety of applications, including document processing and modern genetics. Conventional clustering methods are unsupervised, meaning that there is no outcome variable nor is anything known about the relationship between the observations in the data set. In many situations, however, information about the clusters is available in addition to the values of the features. For example, the cluster labels of some observations may be known, or certain observations may be known to belong to the same cluster. In other cases, one may wish to identify clusters that are associated with a particular outcome variable. This review describes several clustering algorithms (known as “semi-supervised clustering” methods) that can be applied in these situations. The majority of these methods are modifications of the popular k-means clustering method, and several of them will be described in detail. A brief description of some other semi-supervised clustering algorithms is also provided. PMID:24729830
Historical Causes and Future Projections of Hydrological Drought Change over a Semi-arid Watershed in the Yellow River Basin

NASA Astrophysics Data System (ADS)

Jiao, Y.; Yuan, X.; Yang, D.

2017-12-01

During the past five decades, significant decreasing trends in streamflow records were observed at many hydrological gauges within the middle reaches of the Yellow River basin, China, leading to an intensified water resource shortage and a rising hydrological drought risk. This phenomenon is generally considered as a consequence of climate changes and human interventions, such as greenhouse gas emissions, regional land use/cover changes, dam and reservoir constructions and direct water withdrawals. There are many studies on the attribution of streamflow decline and hydrological drought change in this region, while a consolidated conclusion is missing.In this study, we focus on historical and future hydrological drought characteristics over a semi-arid watershed located in the middle reaches of the Yellow River basin. Daily climate simulations from several IPCC CMIP5 models were collected to drive a newly developed eco-hydrological model CLM-GBHM with detailed description of river network and sub-basin topological relationship, to simulate streamflow series under different forcings and scenarios. The standard streamflow index was calculated and used to figure out the characteristics (e.g., frequency, duration and severity) of both historical and future hydrological droughts. The causes and contributions in terms of natural and anthropogenic influences will be investigated based on an optimal fingerprinting method, and the relative importance of internal variability, model and scenario uncertainties for future projections will also be estimated using a separation method. This study will facilitate the implementation of adaptation strategies for hydrological drought over the semi-arid watershed in a changing environment.
Flux-gate magnetometer spin axis offset calibration using the electron drift instrument

NASA Astrophysics Data System (ADS)

Plaschke, Ferdinand; Nakamura, Rumi; Leinweber, Hannes K.; Chutter, Mark; Vaith, Hans; Baumjohann, Wolfgang; Steller, Manfred; Magnes, Werner

2014-10-01

Spin-stabilization of spacecraft immensely supports the in-flight calibration of on-board flux-gate magnetometers (FGMs). From 12 calibration parameters in total, 8 can be easily obtained by spectral analysis. From the remaining 4, the spin axis offset is known to be particularly variable. It is usually determined by analysis of Alfvénic fluctuations that are embedded in the solar wind. In the absence of solar wind observations, the spin axis offset may be obtained by comparison of FGM and electron drift instrument (EDI) measurements. The aim of our study is to develop methods that are readily usable for routine FGM spin axis offset calibration with EDI. This paper represents a major step forward in this direction. We improve an existing method to determine FGM spin axis offsets from EDI time-of-flight measurements by providing it with a comprehensive error analysis. In addition, we introduce a new, complementary method that uses EDI beam direction data instead of time-of-flight data. Using Cluster data, we show that both methods yield similarly accurate results, which are comparable yet more stable than those from a commonly used solar wind-based method.
Holocene relative sea-level change in Hiroshima Bay, Japan: A semi-quantitative reconstruction based on ostracodes

USGS Publications Warehouse

Yasuhara, Moriaki; Seto, Koji

2006-01-01

Holocene relative sea-level changes in Hiroshima Bay were reconstructed from fossil ostracodes from a core, using a semi-quantitative method. In Hiroshima Bay, relative sea level rose rapidly (about 25 m) between ca. 9000 cal yr BP and ca. 5800 cal yr BP, after which it gradually fell (about 5 m) to its present level. The peak in relative sea level occurred at ca. 5800 cal yr BP. The sea-level curve for Hiroshima Bay is similar to curves for tectonically stable areas of Japan (e.g., Osaka Bay). ?? by the Palaeontological Society of Japan.
Semi-active suspension for automotive application

NASA Astrophysics Data System (ADS)

Venhovens, Paul J. T.; Devlugt, Alex R.

The theoretical considerations for semi-active damping system evaluation, with respect to semi-active suspension and Kalman filtering, are discussed in terms of the software. Some prototype hardware developments are proposed. A significant improvement in ride comfort performance can be obtained, indicated by root mean square body acceleration values and frequency responses, using a switchable damper system with two settings. Nevertheless the improvement is accompanied by an increase in dynamic tire load variations. The main benefit of semi-active suspensions is the potential of changing the low frequency section of the transfer function. In practice this will support the impression of extra driving stability. It is advisable to apply an adaptive control strategy like the (extended) skyhook version switching more to the 'comfort' setting for straight (and smooth/moderate roughness) road running and switching to 'road holding' for handling maneuvers and possibly rough roads and discrete, severe events like potholes.
Single-axis gyroscopic motion with uncertain angular velocity about spin axis

NASA Technical Reports Server (NTRS)

Singh, S. N.

1977-01-01

A differential game approach is presented for studying the response of a gyro by treating the controlled angular velocity about the input axis as the evader, and the bounded but uncertain angular velocity about the spin axis as the pursuer. When the uncertain angular velocity about the spin axis desires to force the gyro to saturation a differential game problem with two terminal surfaces results, whereas when the evader desires to attain the equilibrium state the usual game with single terminal manifold arises. A barrier, delineating the capture zone (CZ) in which the gyro can attain saturation and the escape zone (EZ) in which the evader avoids saturation is obtained. The CZ is further delineated into two subregions such that the states in each subregion can be forced on a definite target manifold. The application of the game theoretic approach to Control Moment Gyro is briefly discussed.

Rhythmicity in Mice Selected for Extremes in Stress Reactivity: Behavioural, Endocrine and Sleep Changes Resembling Endophenotypes of Major Depression

PubMed Central

Ruschel, Jörg; Palme, Rupert; Holsboer, Florian; Kimura, Mayumi; Landgraf, Rainer

2009-01-01

Background Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, including hyper- or hypo-activity of the stress hormone system, plays a critical role in the pathophysiology of mood disorders such as major depression (MD). Further biological hallmarks of MD are disturbances in circadian rhythms and sleep architecture. Applying a translational approach, an animal model has recently been developed, focusing on the deviation in sensitivity to stressful encounters. This so-called ‘stress reactivity’ (SR) mouse model consists of three separate breeding lines selected for either high (HR), intermediate (IR), or low (LR) corticosterone increase in response to stressors. Methodology/Principle Findings In order to contribute to the validation of the SR mouse model, our study combined the analysis of behavioural and HPA axis rhythmicity with sleep-EEG recordings in the HR/IR/LR mouse lines. We found that hyper-responsiveness to stressors was associated with psychomotor alterations (increased locomotor activity and exploration towards the end of the resting period), resembling symptoms like restlessness, sleep continuity disturbances and early awakenings that are commonly observed in melancholic depression. Additionally, HR mice also showed neuroendocrine abnormalities similar to symptoms of MD patients such as reduced amplitude of the circadian glucocorticoid rhythm and elevated trough levels. The sleep-EEG analyses, furthermore, revealed changes in rapid eye movement (REM) and non-REM sleep as well as slow wave activity, indicative of reduced sleep efficacy and REM sleep disinhibition in HR mice. Conclusion/Significance Thus, we could show that by selectively breeding mice for extremes in stress reactivity, clinically relevant endophenotypes of MD can be modelled. Given the importance of rhythmicity and sleep disturbances as biomarkers of MD, both animal and clinical studies on the interaction of behavioural, neuroendocrine and sleep parameters may reveal
AXIS - A High Angular Resoltuion X-ray Probe Concept Study

NASA Astrophysics Data System (ADS)

Mushotzky, Richard; AXIS Study Team

2018-01-01

AXIS is a probe-class concept under study to the 2020 Decadal survey. AXIS will extend and enhance the science of high angular resolution x-ray imaging and spectroscopy in the next decade with ~0.3" angular resolution over a 7' radius field of view and an order of magnitude more collecting area than Chandra in the 0.3-12 keV band with a cost consistent with a probe.These capabilities enable major advances in a wide range of science such as: (1) measuring the event horizon scale structure in AGN accretion disks and the spins of supermassive black holes through observations of gravitationally-microlensed quasars; (ii) determining AGN and starburst feedback in galaxies and galaxy clusters through direct imaging of winds and interaction of jets and via spatially resolved imaging of galaxies at high-z; (iii) fueling of AGN by probing the Bondi radius of over 20 nearby galaxies; (iv) hierarchical structure formation and the SMBH merger rate through measurement of the occurrence rate of dual AGN and occupation fraction of SMBHs; (v) advancing SNR physics and galaxy ecology through large detailed samples of SNR in nearby galaxies; (vi) measuring the Cosmic Web through its connection to cluster outskirts. With a nominal 2028 launch, AXIS benefits from natural synergies with the ELTs, LSST, ALMA, WFIRST and ATHENA. AXIS utilizes breakthroughs in the construction of lightweight X-ray optics from mono-crystalline silicon blocks, and developments in the fabrication of large format, small pixel, high readout rate detectors allowing a robust and cost effective design. The AXIS team welcomes input and feedback from the community in preparation for the 2020 Decadal review.
Predictive brain networks for major depression in a semi-multimodal fusion hierarchical feature reduction framework.

PubMed

Yang, Jie; Yin, Yingying; Zhang, Zuping; Long, Jun; Dong, Jian; Zhang, Yuqun; Xu, Zhi; Li, Lei; Liu, Jie; Yuan, Yonggui

2018-02-05

Major depressive disorder (MDD) is characterized by dysregulation of distributed structural and functional networks. It is now recognized that structural and functional networks are related at multiple temporal scales. The recent emergence of multimodal fusion methods has made it possible to comprehensively and systematically investigate brain networks and thereby provide essential information for influencing disease diagnosis and prognosis. However, such investigations are hampered by the inconsistent dimensionality features between structural and functional networks. Thus, a semi-multimodal fusion hierarchical feature reduction framework is proposed. Feature reduction is a vital procedure in classification that can be used to eliminate irrelevant and redundant information and thereby improve the accuracy of disease diagnosis. Our proposed framework primarily consists of two steps. The first step considers the connection distances in both structural and functional networks between MDD and healthy control (HC) groups. By adding a constraint based on sparsity regularization, the second step fully utilizes the inter-relationship between the two modalities. However, in contrast to conventional multi-modality multi-task methods, the structural networks were considered to play only a subsidiary role in feature reduction and were not included in the following classification. The proposed method achieved a classification accuracy, specificity, sensitivity, and area under the curve of 84.91%, 88.6%, 81.29%, and 0.91, respectively. Moreover, the frontal-limbic system contributed the most to disease diagnosis. Importantly, by taking full advantage of the complementary information from multimodal neuroimaging data, the selected consensus connections may be highly reliable biomarkers of MDD. Copyright © 2017 Elsevier B.V. All rights reserved.
Building integrated semi-transparent photovoltaics: energy and daylighting performance

NASA Astrophysics Data System (ADS)

Kapsis, Konstantinos; Athienitis, Andreas K.

2011-08-01

This paper focuses on modeling and evaluation of semi-transparent photovoltaic technologies integrated into a coolingdominated office building façade by employing the concept of three-section façade. An energy simulation model is developed, using building simulation software, to investigate the effect of semi-transparent photovoltaic transmittance on the energy performance of an office in a typical office building in Montreal. The analysis is performed for five major façade orientations and two façade configurations. Using semi-transparent photovoltaic integrated into the office façade, electricity savings of up to 53.1% can be achieved compared to a typical office equipped with double glazing with Argon filling and a low emissivity coating, and lighting controlled based on occupancy and daylight levels.e.c
20 CFR 418.1260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What major life-changing event evidence will we not accept? 418.1260 Section 418.1260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE... Year's Modified Adjusted Gross Income § 418.1260 What major life-changing event evidence will we not...
20 CFR 418.1260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What major life-changing event evidence will we not accept? 418.1260 Section 418.1260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE... Year's Modified Adjusted Gross Income § 418.1260 What major life-changing event evidence will we not...
Detection of changes in semi-natural grasslands by cross correlation analysis with WorldView-2 images and new Landsat 8 data.

PubMed

Tarantino, Cristina; Adamo, Maria; Lucas, Richard; Blonda, Palma

2016-03-15

Focusing on a Mediterranean Natura 2000 site in Italy, the effectiveness of the cross correlation analysis (CCA) technique for quantifying change in the area of semi-natural grasslands at different spatial resolutions (grain) was evaluated. In a fine scale analysis (2 m), inputs to the CCA were a) a semi-natural grasslands layer extracted from an existing validated land cover/land use (LC/LU) map (1:5000, time T 1 ) and b) a more recent single date very high resolution (VHR) WorldView-2 image (time T 2 ), with T 2 > T 1 . The changes identified through the CCA were compared against those detected by applying a traditional post-classification comparison (PCC) technique to the same reference T 1 map and an updated T 2 map obtained by a knowledge driven classification of four multi-seasonal Worldview-2 input images. Specific changes observed were those associated with agricultural intensification and fires. The study concluded that prior knowledge (spectral class signatures, awareness of local agricultural practices and pressures) was needed for the selection of the most appropriate image (in terms of seasonality) to be acquired at T 2 . CCA was also applied to the comparison of the existing T 1 map with recent high resolution (HR) Landsat 8 OLS images. The areas of change detected at VHR and HR were broadly similar with larger error values in HR change images.
Osmoregulatory actions of the GH/IGF axis in non-salmonid teleosts

USGS Publications Warehouse

Mancera, J.M.; McCormick, S.D.

1998-01-01

Salmonid fishes provided the first findings on the influence of the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis on osmoregulation in teleost fishes. Recent studies on non-salmonid species, however, indicate that this physiological action of the GH/IGF-I axis is not restricted to salmonids or anadromous fishes. GH-producing cells in the pituitary of fish acclimated to different salinities show different degrees of activation depending on the species studied. Plasma GH levels either increase or do not change after transfer of fish from freshwater to seawater. Treatment with GH or IGF-I increases salinity tolerance and/or increases gill Na+,K+-ATPase activity of killifish (Fundulus heteroclitus), tilapia (Oreochromis mossambicus and Oreochromisniloticus) and striped bass (Morone saxatilis). As in salmonids, a positive interaction between GH and cortisol for improving hypoosmoregulatory capacity has been described in tilapia (O. mossambicus). Research on the osmoregulatory role of the GH/IGF-I axis is derived from a small number of teleost species. The study of more species with different osmoregulary patterns will be necessary to fully clarify the osmoregulatory role of GH/IGF-I axis in fish. The available data does suggest, however, that the influence of the GH/IGF-I axis on osmoregulation may be a common feature of euryhalinity in teleosts.
Inversion of the chordate body axis: are there alternatives?

NASA Technical Reports Server (NTRS)

Gerhart, J.

2000-01-01

One major morphological difference between chordates and annelids or arthropods is the opposite orientation of the nerve cord and heart. A long-standing proposal is that the chordate axis evolved by inverting the body of an ancestor with the annelid/arthropod orientation. However, the data can also be explained by a common ancestor with diffuse dorsoventral organization, followed by oppositely directed condensation of the nerve cord and relocation of the heart in the two lines.
Factors determining the spin axis of a pitched fastball in baseball.

PubMed

Jinji, Tsutomu; Sakurai, Shinji; Hirano, Yuichi

2011-04-01

In this study, we wished to investigate the factors that determine the direction of the spin axis of a pitched baseball. Nineteen male baseball pitchers were recruited to pitch fastballs. The pitching motion was recorded with a three-dimensional motion analysis system (1000 Hz), and the orientations of the hand segment in a global coordinate system were calculated using Euler rotation angles. Reflective markers were attached to the ball, and the direction of the spin axis was calculated on the basis of their positional changes. The spin axis directions were significantly correlated with the orientations of the hand just before ball release. The ball is released from the fingertip and rotates on a plane that is formed by the palm and fingers; the spin axis of the ball is parallel to this plane. The lift force of the pitched baseball is largest when the angular and translational velocity vectors are mutually perpendicular. Furthermore, to increase the lift forces for the fastballs, the palm must face home plate.
Growth axis maturation is linked to nutrition, growth and developmental rate.

PubMed

Hetz, Jennifer A; Menzies, Brandon R; Shaw, Geoffrey; Rao, Alexandra; Clarke, Iain J; Renfree, Marilyn B

2015-08-15

Maturation of the mammalian growth axis is thought to be linked to the transition from fetal to post-natal life at birth. However, in an altricial marsupial, the tammar wallaby (Macropus eugenii), this process occurs many months after birth but at a time when the young is at a similar developmental stage to that of neonatal eutherian mammals. Here we manipulate growth rates and demonstrate in slow, normal and fast growing tammar young that nutrition and growth rate affect the time of maturation of the growth axis. Maturation of GH/IGF-I axis components occurred earlier in fast growing young, which had significantly increased hepatic GHR, IGF1 and IGFALS expression, plasma IGF-I concentrations, and significantly decreased plasma GH concentrations compared to age-matched normal young. These data support the hypothesis that the time of maturation of the growth axis depends on the growth rate and maturity of the young, which can be accelerated by changing their nutritional status. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
20 CFR 418.2260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false What major life-changing event evidence will we not accept? 418.2260 Section 418.2260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE... Using A More Recent Tax Year's Modified Adjusted Gross Income § 418.2260 What major life-changing event...
20 CFR 418.2260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false What major life-changing event evidence will we not accept? 418.2260 Section 418.2260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE... Using A More Recent Tax Year's Modified Adjusted Gross Income § 418.2260 What major life-changing event...
20 CFR 418.2260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false What major life-changing event evidence will we not accept? 418.2260 Section 418.2260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE... Using A More Recent Tax Year's Modified Adjusted Gross Income § 418.2260 What major life-changing event...
Prevalence and risk factors of major depressive disorder in HIV/AIDS as seen in semi-urban Entebbe district, Uganda

PubMed Central

2011-01-01

Background Not much is known about the risk factors of major depressive disorder (MDD) in HIV/AIDS in the African socio-cultural context. Therefore a study was undertaken to examine the prevalence and risk factors of MDD in HIV/AIDS in semi-urban Uganda. Methods A cross-sectional study was undertaken among 618 respondents attending two HIV clinics in Uganda. Results Prevalence of MDD was 8.1%. Factors associated with MDD at univariate analysis only were female gender, family history of mental illness, negative coping style, alcohol dependency disorder, food insecurity and stress; not associated with MDD were social support, neurocognitive impairment, CD4 counts and BMI. Factors independently associated with MDD were psychosocial impairment, adverse life events, post traumatic stress disorder, generalised anxiety disorder and life-time attempted suicide. Conclusion Psychological and social factors were the main risk factors of MDD among ambulatory HIV positive persons with no evidence for the role of the neurotoxic effects of HIV. Treatment approaches for MDD in this patient group should be modeled on those used among non-HIV groups. PMID:22208452
Mapping local anisotropy axis for scattering media using backscattering Mueller matrix imaging

NASA Astrophysics Data System (ADS)

He, Honghui; Sun, Minghao; Zeng, Nan; Du, E.; Guo, Yihong; He, Yonghong; Ma, Hui

2014-03-01

Mueller matrix imaging techniques can be used to detect the micro-structure variations of superficial biological tissues, including the sizes and shapes of cells, the structures in cells, and the densities of the organelles. Many tissues contain anisotropic fibrous micro-structures, such as collagen fibers, elastin fibers, and muscle fibers. Changes of these fibrous structures are potentially good indicators for some pathological variations. In this paper, we propose a quantitative analysis technique based on Mueller matrix for mapping local anisotropy axis of scattering media. By conducting both experiments on silk sample and Monte Carlo simulation based on the sphere-cylinder scattering model (SCSM), we extract anisotropy axis parameters from different backscattering Mueller matrix elements. Moreover, we testify the possible applications of these parameters for biological tissues. The preliminary experimental results of human cancerous samples show that, these parameters are capable to map the local axis of fibers. Since many pathological changes including early stage cancers affect the well aligned structures for tissues, the experimental results indicate that these parameters can be used as potential tools in clinical applications for biomedical diagnosis purposes.
Optimal pitching axis location of flapping wings for efficient hovering flight.

PubMed

Wang, Q; Goosen, J F L; van Keulen, F

2017-09-01

Flapping wings can pitch passively about their pitching axes due to their flexibility, inertia, and aerodynamic loads. A shift in the pitching axis location can dynamically alter the aerodynamic loads, which in turn changes the passive pitching motion and the flight efficiency. Therefore, it is of great interest to investigate the optimal pitching axis for flapping wings to maximize the power efficiency during hovering flight. In this study, flapping wings are modeled as rigid plates with non-uniform mass distribution. The wing flexibility is represented by a linearly torsional spring at the wing root. A predictive quasi-steady aerodynamic model is used to evaluate the lift generated by such wings. Two extreme power consumption scenarios are modeled for hovering flight, i.e. the power consumed by a drive system with and without the capacity of kinetic energy recovery. For wings with different shapes, the optimal pitching axis location is found such that the cycle-averaged power consumption during hovering flight is minimized. Optimization results show that the optimal pitching axis is located between the leading edge and the mid-chord line, which shows close resemblance to insect wings. An optimal pitching axis can save up to 33% of power during hovering flight when compared to traditional wings used by most of flapping wing micro air vehicles (FWMAVs). Traditional wings typically use the straight leading edge as the pitching axis. With the optimized pitching axis, flapping wings show higher pitching amplitudes and start the pitching reversals in advance of the sweeping reversals. These phenomena lead to higher lift-to-drag ratios and, thus, explain the lower power consumption. In addition, the optimized pitching axis provides the drive system higher potential to recycle energy during the deceleration phases as compared to their counterparts. This observation underlines the particular importance of the wing pitching axis location for energy-efficient FWMAVs when
20 CFR 418.1260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false What major life-changing event evidence will... Year's Modified Adjusted Gross Income § 418.1260 What major life-changing event evidence will we not... source. (e) We will not accept evidence of work reduction or work stoppage that cannot be substantiated. ...
Surgeons' efficiency change is a major determinant of their productivity change.

PubMed

Nakata, Yoshinori; Watanabe, Yuichi; Narimatsu, Hiroto; Yoshimura, Tatsuya; Otake, Hiroshi; Sawa, Tomohiro

2016-05-09

Purpose - The sustainability of the Japanese healthcare system is in question because the government has had a huge fiscal debt. Despite an enormous effort to cut the deficit, our healthcare expenditure is increasing every year because of the rapidly aging population. One of the solutions for this problem is to improve the productivity of healthcare. The purpose of this paper is to determine the factors that change surgeons' productivity in one year. Design/methodology/approach - The authors collected data of all surgical procedures performed at Teikyo University Hospital from April 1 through September 30 in 2014 and 2015, and computed the surgeons' Malmquist index (MI), efficiency change (EC) and technical change (TC) using non-radial and non-oriented Malmquist model under the constant returns-to-scale assumptions. The authors then divided the surgeons into two groups; one whose productivity progressed and the other whose productivity regressed. These two groups were compared to identify factors that may influence their MI. Findings - The only significant difference between the two groups was ECs (p < 0.0001). The other factors, such as TC, experience, surgical volume, emergency cases, surgical specialty, academic ranks, medical schools and gender, were not significantly different between the two groups. Originality/value - EC is a major determinant of surgeons' productivity change. The best way to improve surgeons' productivity may be to enhance their efficiency regardless of their surgical volume and personal backgrounds.
Hypothalamic-pituitary-adrenal (HPA) axis function in the California mouse (Peromyscus californicus): Changes in baseline activity, reactivity, and fecal excretion of glucocorticoids across the diurnal cycle

PubMed Central

Harris, Breanna N.; Saltzman, Wendy; de Jong, Trynke R.; Milnes, Matthew R.

2012-01-01

The California mouse, Peromyscus californicus, is an increasingly popular animal model in behavioral, neural, and endocrine studies, but little is known about its baseline hypothalamicpituitary-adrenal (HPA) axis activity or HPA responses to stressors. We characterized plasma corticosterone (CORT) concentrations in P. californicus under baseline conditions across the diurnal cycle, in response to pharmacological manipulation of the HPA axis, and in response to a variety of stressors at different times of day. In addition, we explored the use of fecal samples to monitor adrenocortical activity non-invasively. California mice have very high baseline levels of circulating CORT that change markedly over 24 hours, but that do not differ between the sexes. This species may be somewhat glucocorticoid-resistant in comparison to other rodents as a relatively high dose of dexamethasone (5 mg/kg, s.c.) was required to suppress plasma CORT for 8 h post-injection. CORT responses to stressors and ACTH injection differed with time of day, as CORT concentrations were elevated more readily during the morning (inactive period) than in the evening (active period) when compared to time-matched control. Data from 3H-CORT injection studies show that the time course for excretion of fecal CORT, or glucocorticoid metabolites, differs with time of injection. Mice injected in the evening excreted the majority of fecal radioactivity 2–4 h post-injection whereas mice injected during the morning did so at 14–16 h post-injection. Unfortunately, the antibody we used does not adequately bind the most prevalent fecal glucocorticoid metabolites and therefore we could not validate its use for fecal assays. PMID:23026495

Climate Warming Threatens Semi-arid Forests in Inner Asia

NASA Astrophysics Data System (ADS)

WU, X.; Liu, H.; Qi, Z.; Li, X.

2014-12-01

A line of evidences reveal an increasing tree growth decline and tree mortality mainly attributable to climate warming and the warming-mediated changes in drought and other processes (such as fire and insect dynamics) in many parts of world tropical, temperate and boreal forests. However, the growth responses to climate change of the widely distributed semi-arid forests are unclear. Here, we synthetically investigate the tree growth patterns during past decades and its interannual response to climate variations in Inner Asia combining the ground truth field survey and samplings, remote sensing observations and climate data. We identified a pervasive tree growth decline since mid-1990s in semi-arid forests in Inner Asia. The widely observed tree growth decline is dominantly attributable to warming-induced water stress during pre- and early growing season. Tree growth of semi-arid forests in Inner Asia is particularly susceptible to spring warming and has been suffering a prolonged growth limitation in recent decades due to spring warming-mediated water conditions. Additionally, we identified a much slower growth rate in younger trees and a lack of tree regeneration in these semi-arid forests. The widely observed forest growth reduction and lack of tree regeneration over semi-arid forests in Inner Asia could predictably exert great effects on forest structure, regionally/globally biophysical and biochemical processes and the feedbacks between biosphere and atmosphere. Notably, further increases in forest stress and tree mortality could be reasonably expected, especially in context of the increase frequency and severity of high temperature and heat waves and changes in forest disturbances, potentially driving the eventual regional loss of current semi-arid forests. Given the potential risks of climate induced forest dieback, increased management attention to adaptation options for enhancing forest resistance and resilience to projected climate stress can be expected
Optics ellipticity performance of an unobscured off-axis space telescope.

PubMed

Zeng, Fei; Zhang, Xin; Zhang, Jianping; Shi, Guangwei; Wu, Hongbo

2014-10-20

With the development of astronomy, more and more attention is paid to the survey of dark matter. Dark matter cannot be seen directly but can be detected by weak gravitational lensing measurement. Ellipticity is an important parameter used to define the shape of a galaxy. Galaxy ellipticity changes with weak gravitational lensing and nonideal optics. With our design of an unobscured off-axis telescope, we implement the simulation and calculation of optics ellipticity. With an accurate model of optics PSF, the characteristic of ellipticity is modeled and analyzed. It is shown that with good optical design, the full field ellipticity can be quite small. The spatial ellipticity change can be modeled by cubic interpolation with very high accuracy. We also modeled the ellipticity variance with time and analyzed the tolerance. It is shown that the unobscured off-axis telescope has good ellipticity performance and fulfills the requirement of dark matter survey.
Plasticity of the reproductive axis caused by social status change in an african cichlid fish: II. testicular gene expression and spermatogenesis.

PubMed

Maruska, Karen P; Fernald, Russell D

2011-01-01

Reproduction in all vertebrates is controlled by the brain-pituitary-gonad (BPG) axis, which is regulated socially in males of the African cichlid fish Astatotilapia burtoni. Although social information influences GnRH1 neurons at the apex of the BPG axis, little is known about how the social environment and dominance affects the cellular and molecular composition of the testes to regulate reproductive capacity. We created an opportunity for reproductively suppressed males to ascend in status and then measured changes in gene expression and tissue morphology to discover how quickly the perception of this opportunity can influence the testes. Our results show rapid up-regulation of mRNA levels of FSH receptor and several steroid receptor subtypes in the testes during social ascent. In contrast, LH receptor was not elevated until 72 h after ascent, but this increase was coincident with elevated circulating androgens and early stages of spermatogenesis, suggesting a role in steroidogenesis. The spermatogenic potential of the testes, as measured by cellular composition, was also elevated before the overall increase in testes size. The presence of cysts at all stages of spermatogenesis, coupled with lower levels of gonadotropin and steroid receptors in subordinate males, suggests that the BPG axis and spermatogenesis are maintained at a subthreshold level in anticipation of the chance to gain a territory and become reproductively active. Our results show that the testis is stimulated extremely quickly after perception of social opportunity, presumably to allow suppressed males to rapidly achieve high reproductive success in a dynamic social environment.
Axial crustal structure of the Costa Rica Rift: Implications for along-axis hydrothermal circulation

NASA Astrophysics Data System (ADS)

Zhang, L.; Tong, V.; Hobbs, R. W.; Peirce, C.; Lowell, R. P.; Haughton, G.; Murton, B. J.; Morales Maqueda, M. A.; Harris, R. N.; Robinson, A. H.

2017-12-01

In 2015, a multidisciplinary geophysical cruise surveyed the Costa Rica Rift (CRR) in the Panama Basin of the equatorial East Pacific, acquiring a grid of multichannel seismic and wide-angle profiles to determine the mode of oceanic crustal accretion at intermediate-spreading ridges, and how the crustal structure may be influenced by hydrothermal fluid flow. Analysis of 69,000 P-wave first arrivals recorded by 25 ocean-bottom seismographs deployed over a 20 × 20 km area that straddles the ridge axis, reveals a 3D velocity-depth model of upper crustal structure. In particular, the model shows a low velocity anomaly that extends to 2 km below seabed centred on a small-offset non-transform discontinuity (NTD), and a pattern of increasing velocity with distance off-axis that may reflect changes in porosity and permeability in layer 2 of the crust. Assuming the upper crustal velocity anomalies are linked with porosity and hence represent the ability of fluid to flow, comparison of the tomographic model with the volcanic seabed morphology suggests that the broad low velocity zone beneath the NTD may be a region of extensive fracturing. Hence, we infer that this region may provide a primary pathway for the recharge of seawater into the crust. Further west along the axis, beneath the bathymetric dome, which is the shallowest portion along the axis, the low-velocity anomaly is less pronounced, suggesting that fractures are less open and that fluid-rock interaction has encouraged mineral precipitation and alteration, as a result of a longer established hydrothermal fluid flow driven by the axial magma lens observed beneath it. This interpretation is supported by the presence of a plume from an active hydrothermal vent system. Hence, we infer that the variable velocity structure of the upper crust of the CRR is a proxy that reflects the primary porosity, faulting and fracturing related to phases of magma-driven accretion and/or ridge geometry re-adjustment, and that there is
Involvement of Endogenous Brain-Derived Neurotrophic Factor in Hypothalamic-Pituitary-Adrenal Axis Activity.

PubMed

Naert, G; Zussy, C; Tran Van Ba, C; Chevallier, N; Tang, Y-P; Maurice, T; Givalois, L

2015-11-01

Brain-derived neurotrophic factor (BDNF) appears to be highly involved in hypothalamic-pituitary-adrenal (HPA) axis regulation during adulthood, playing an important role in homeostasis maintenance. The present study aimed to determine the involvement of BDNF in HPA axis activity under basal and stress conditions via partial inhibition of this endogenous neurotrophin. Experiments were conducted in rats and mice with two complementary approaches: (i) BDNF knockdown with stereotaxic delivery of BDNF-specific small interfering RNA (siRNA) into the lateral ventricle of adult male rats and (ii) genetically induced knockdown (KD) of BDNF expression specifically in the central nervous system during the first ontogenesis in mice (KD mice). Delivery of siRNA in the rat brain decreased BDNF levels in the hippocampus (-31%) and hypothalamus (-35%) but not in the amygdala, frontal cortex and pituitary. In addition, siRNA induced no change of the basal HPA axis activity. BDNF siRNA rats exhibited decreased BDNF levels and concomitant altered adrenocortoctrophic hormone (ACTH) and corticosterone responses to restraint stress, suggesting the involvement of BDNF in the HPA axis adaptive response to stress. In KD mice, BDNF levels in the hippocampus and hypothalamus were decreased by 20% in heterozygous and by 60% in homozygous animals compared to wild-type littermates. Although, in heterozygous KD mice, no significant change was observed in the basal levels of plasma ACTH and corticosterone, both hormones were significantly increased in homozygous KD mice, demonstrating that robust cerebral BDNF inhibition (60%) is necessary to affect basal HPA axis activity. All of these results in both rats and mice demonstrate the involvement and importance of a robust endogenous pool of BDNF in basal HPA axis regulation and the pivotal function of de novo BDNF synthesis in the establishment of an adapted response to stress. © 2015 British Society for Neuroendocrinology.
Application of external axis in thermal spraying

NASA Astrophysics Data System (ADS)

Gao, Guoyou; Wang, Wei; Chen, Tao; Hui, Chun

2018-05-01

Industrial robots are widely used nowadays in the process of thermal spraying, human work can be largely replaced due to the high-efficient, security, precision and repeatability of industrial robot. As offering the convenience to industrial product, Robots have some natural deficiencies because of its mechanical linkages of six-axis. When robot performs a series of stage of production, it could be hard to move to the next one because one of his axis reaches a maximum value. For this reason, external axis is added to robot system to extend the reachable space of robot axis. This paper concerns to the application of external axis and the different methods of programming the robot with work-holding external axis in the virtual environment. Experiments demonstrate the coating layer on the regular workpiece is uniform.
Charge Inversion in semi-permeable membranes

NASA Astrophysics Data System (ADS)

Das, Siddhartha; Sinha, Shayandev; Jing, Haoyuan

Role of semi-permeable membranes like lipid bilayer is ubiquitous in a myriad of physiological and pathological phenomena. Typically, lipid membranes are impermeable to ions and solutes; however, protein channels embedded in the membrane allow the passage of selective, small ions across the membrane enabling the membrane to adopt a semi-permeable nature. This semi-permeability, in turn, leads to electrostatic potential jump across the membrane, leading to effects such as regulation of intracellular calcium, extracellular-vesicle-membrane interactions, etc. In this study, we theoretically demonstrate that this semi-permeable nature may trigger the most remarkable charge inversion (CI) phenomenon in the cytosol-side of the negatively-charged lipid bilayer membrane that are selectively permeable to only positive ions of a given salt. This CI is manifested as the changing of the sign of the electrostatic potential from negative to positive from the membrane-cytosol interface to deep within the cytosol. We study the impact of the parameters such as the concentration of this salt with selectively permeable ions as well as the concentration of an external salt in the development of this CI phenomenon. We anticipate such CI will profoundly influence the interaction of membrane and intra-cellular moieties (e.g., exosome or multi-cellular vesicles) having implications for a host of biophysical processes.
Modulation of the Hypothalamic-Pituitary-Adrenal Axis by Early Life Stress Exposure

PubMed Central

van Bodegom, Miranda; Homberg, Judith R.; Henckens, Marloes J. A. G.

2017-01-01

hyper-reactivity in adulthood, as also found in major depression. This hyper-activity is related to increased corticotrophin-releasing hormone signaling and impaired glucocorticoid receptor-mediated negative feedback. In contrast, initial evidence for HPA-axis hypo-reactivity is observed for early social deprivation, potentially reflecting the abnormal HPA-axis function as observed in post-traumatic stress disorder, and future studies should investigate its neural/neuroendocrine foundation in further detail. Interestingly, experiencing additional (chronic) stress in adulthood seems to normalize these alterations in HPA-axis function, supporting the match/mismatch theory. PMID:28469557
A cytokine axis regulates elastin formation and degradation

PubMed Central

Sproul, Erin P.; Argraves, W. Scott

2013-01-01

Underlying the dynamic regulation of tropoelastin expression and elastin formation in development and disease are transcriptional and post-transcriptional mechanisms that have been the focus of much research. Of particular importance is the cytokine–governed elastin regulatory axis in which the pro-elastogenic activities of transforming growth factor β-1 (TGFβ1) and insulin-like growth factor-I (IGF-I) are opposed by anti-elastogenic activities of basic fibroblast growth factor (bFGF/FGF-2), heparin-binding epidermal growth factor-like growth factor (HB-EGF), EGF, PDGF-BB, TGFα, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β and noncanonical TGFβ1 signaling. A key mechanistic feature of the regulatory axis is that cytokines influence elastin formation through effects on the cell cycle involving control of cyclin–cyclin dependent kinase complexes and activation of the Ras/MEK/ERK signaling pathway. In this article we provide an overview of the major cytokines/growth factors that modulate elastogenesis and describe the underlying molecular mechanisms for their action on elastin production. PMID:23160093
Osmoregulatory actions of the GH/IGF axis in non-salmonid teleosts

USGS Publications Warehouse

Mancera, J.M.; McCormick, S.D.

1998-01-01

Salmonid fishes provided the first findings on the influence of the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis on osmoregulation in teleost fishes. Recent studies on non-salmonid species, however, indicate that this physiological action of the GH/IGF-I axis is not restricted to salmonids or anadromous fishes. GH-producing cells in the pituitary of fish acclimated to different salinities show different degrees of activation depending on the species studied. Plasma GH levels either increase or do not change after transfer of fish from freshwater to seawater. Treatment with GH or IGF-I increases salinity tolerance and/or increases gill Na+,K+-ATPase activity of killifish (Fundulus heteroclitus), tilapia (Oreochromis mossambicus and Oreochromis niloticus) and striped bass (Morone saxatilis). As in salmonids, a positive interaction between GH and cortisol for improving hypoosmoregulatory capacity has been described in tilapia (O. mossambicus). Research on the osmoregulatory role of the GH/IGF-I axis is derived from a small number of teleost species. The study of more species with different osmoregulary patterns will be necessary to fully clarify the osmoregulatory role of GH/IGF-I axis in fish. The available data does suggest, however, that the influence of the GH/IGF-I axis on osmoregulation may be a common feature of euryhalinity in teleosts. Copyright (C) 1998 Elsevier Science Inc.
Microbiota, cirrhosis, and the emerging oral-gut-liver axis

PubMed Central

Acharya, Chathur; Bajaj, Jasmohan S.

2017-01-01

Cirrhosis is a prevalent cause of morbidity and mortality, especially for those at an advanced decompensated stage. Cirrhosis development and progression involves several important interorgan communications, and recently, the gut microbiome has been implicated in pathophysiology of the disease. Dysbiosis, defined as a pathological change in the microbiome, has a variable effect on the compensated versus decompensated stage of cirrhosis. Adverse microbial changes, both in composition and function, can act at several levels within the gut (stool and mucosal) and have also been described in the blood and oral cavity. While dysbiosis in the oral cavity could be a source of systemic inflammation, current cirrhosis treatment modalities are targeted toward the gut-liver axis and do not address the oral microbiome. As interventions designed to modulate oral dysbiosis may delay progression of cirrhosis, a better understanding of this process is of the utmost importance. The concept of oral microbiota dysbiosis in cirrhosis is relatively new; therefore, this review will highlight the emerging role of the oral-gut-liver axis and introduce perspectives for future research. PMID:28978799
Scope of wind energy in Bangladesh and simulation analysis of three different horizontal axis wind turbine blade shapes

NASA Astrophysics Data System (ADS)

Khan, Md. Arif-Ul Islam; Das, Swapnil; Dey, Saikat

2017-12-01

: Economic growth and energy demand are intertwined. Therefore, one of the most important concerns of the government and in the world is the need for energy security. Currently, the world relies on coal, crude oil and natural gas for energy generati on. However, the energy crisis together with climate change and depletion of oil have become major concerns to all countries. Therefore, alternative energy resources such as wind energy attracted interest from both public and private sectors to invest in energy generation from this source extensively. Both Vertical and Horizontal axis wind turbine can be used for this purpose. But, Horizontal axis is the most promising between them due to its efficiency and low expense. Bangladesh being a tropical country does have a lot of wind flow at different seasons of the year. However, there are some windy locations in which wind energy projects could be feasible. In this project a detailed review of the current st ate-of-art for wind turbine blade design is presented including theoretical maximum efficiency, Horizontal Axis Wind Turbine (HAWT) blade design, simulation power and COP values for different blade material. By studying previously collected data on the wind resources available in B angladesh at present and by analyzing this data, this paper will discuss the scope of wind energy in Bangladesh.
Fracture modes in off-axis fiber composites

NASA Technical Reports Server (NTRS)

Sinclair, J. H.; Chamis, C. C.

1978-01-01

Criteria were developed for identifying, characterizing, and quantifying fracture modes in high-modulus graphite-fiber/resin unidirectional composites subjected to off-axis tensile loading. Procedures are described which use sensitivity analyses and off-axis data to determine the uniaxial strength of fiber composites. It was found that off-axis composites fail by three fracture modes which produce unique fracture surface characteristics. The stress that dominates each fracture mode and the load angle range of its dominance can be identified. Linear composite mechanics is adequate to describe quantitatively the mechanical behavior of off-axis composites. The uniaxial strengths predicted from off-axis data are comparable to these measured in uniaxial tests.
Building Better Planet Populations for EXOSIMS

NASA Astrophysics Data System (ADS)

Garrett, Daniel; Savransky, Dmitry

2018-01-01

The Exoplanet Open-Source Imaging Mission Simulator (EXOSIMS) software package simulates ensembles of space-based direct imaging surveys to provide a variety of science and engineering yield distributions for proposed mission designs. These mission simulations rely heavily on assumed distributions of planetary population parameters including semi-major axis, planetary radius, eccentricity, albedo, and orbital orientation to provide heuristics for target selection and to simulate planetary systems for detection and characterization. The distributions are encoded in PlanetPopulation modules within EXOSIMS which are selected by the user in the input JSON script when a simulation is run. The earliest written PlanetPopulation modules available in EXOSIMS are based on planet population models where the planetary parameters are considered to be independent from one another. While independent parameters allow for quick computation of heuristics and sampling for simulated planetary systems, results from planet-finding surveys have shown that many parameters (e.g., semi-major axis/orbital period and planetary radius) are not independent. We present new PlanetPopulation modules for EXOSIMS which are built on models based on planet-finding survey results where semi-major axis and planetary radius are not independent and provide methods for sampling their joint distribution. These new modules enhance the ability of EXOSIMS to simulate realistic planetary systems and give more realistic science yield distributions.
Determination of a sagittal plane axis of rotation for a dynamic office chair.

PubMed

Bauer, C M; Rast, F M; Böck, C; Kuster, R P; Baumgartner, D

2018-10-01

This study investigated the location of the axis of rotation in sagittal plane movement of the spine in a free sitting condition to adjust the kinematics of a mobile seat for a dynamic chair. Dynamic office chairs are designed to avoid continuous isometric muscle activity, and to facilitate increased mobility of the back during sitting. However, these chairs incorporate increased upper body movement which could distract office workers from the performance of their tasks. A chair with an axis of rotation above the seat would facilitate a stable upper back during movements of the lower back. The selection of a natural kinematic pattern is of high importance in order to match the properties of the spine. Twenty-one participants performed four cycles of flexion and extension of the spine during an upper arm hang on parallel bars. The location of the axis of rotation relative to the seat was estimated using infrared cameras and reflective skin markers. The median axis of rotation across all participants was located 36 cm above the seat for the complete movement and 39 cm for both the flexion and extension phases, each with an interquartile range of 20 cm. There was no significant effect of the movement direction on the location of the axis of rotation and only a weak, non-significant correlation between body height and the location of the axis of rotation. Individual movement patterns explained the majority of the variance. The axis of rotation for a spinal flexion/extension movement is located above the seat. The recommended radius for a guide rail of a mobile seat is between 36 cm and 39 cm. Copyright © 2018 Elsevier Ltd. All rights reserved.
Identification and characterization of HPA-axis reactivity endophenotypes in a cohort of female PTSD patients.

PubMed

Zaba, Monika; Kirmeier, Thomas; Ionescu, Irina A; Wollweber, Bastian; Buell, Dominik R; Gall-Kleebach, Dominique J; Schubert, Christine F; Novak, Bozidar; Huber, Christine; Köhler, Katharina; Holsboer, Florian; Pütz, Benno; Müller-Myhsok, Bertram; Höhne, Nina; Uhr, Manfred; Ising, Marcus; Herrmann, Leonie; Schmidt, Ulrike

2015-05-01

Analysis of the function of the hypothalamic-pituitary-adrenal (HPA)-axis in patients suffering from posttraumatic stress disorder (PTSD) has hitherto produced inconsistent findings, inter alia in the Trier Social Stress Test (TSST). To address these inconsistencies, we compared a sample of 23 female PTSD patients with either early life trauma (ELT) or adult trauma (AT) or combined ELT and AT to 18 age-matched non-traumatized female healthy controls in the TSST which was preceded by intensive baseline assessments. During the TSST, we determined a variety of clinical, psychological, endocrine and cardiovascular parameters as well as expression levels of four HPA-axis related genes. Using a previously reported definition of HPA-axis responsive versus non-responsive phenotypes, we identified for the first time two clinically and biologically distinct HPA-axis reactivity subgroups of PTSD. One subgroup ("non-responders") showed a blunted HPA-axis response and distinct clinical and biological characteristics such as a higher prevalence of trauma-related dissociative symptoms and of combined AT and ELT as well as alterations in the expression kinetics of the genes encoding for the mineralocorticoid receptor (MR) and for FK506 binding protein 51 (FKBP51). Interestingly, this non-responder subgroup largely drove the relatively diminished HPA axis response of the total cohort of PTSD patients. These findings are limited by the facts that the majority of patients was medicated, by the lack of traumatized controls and by the relatively small sample size. The here for the first time identified and characterized HPA-axis reactivity endophenotypes offer an explanation for the inconsistent reports on HPA-axis function in PTSD and, moreover, suggest that most likely other factors than HPA-axis reactivity play a decisive role in determination of PTSD core symptom severity. Copyright © 2015 Elsevier Ltd. All rights reserved.
A data-oriented semi-process model for evaluating the yields of major crops at global scale (PRYSBI-2)

NASA Astrophysics Data System (ADS)

Sakurai, G.; Iizumi, T.; Yokozawa, M.

2013-12-01

Demand for major cereal crops will double by 2050 compared to the amount in 2005 due to the population growth, dietary change, and increase in biofuel use. This requires substantial efforts to increase crop yields under changing climate, water resources, and land use. In order to explore possible paths to meet the supply target, global crop modeling is a useful approach. To that end, we developed a process-based large-area crop model (called PRYSBIE-2) for major crops, including soybean. This model consisted of the enzyme kinetics model for photosynthetic carbon assimilation and soil water balance model from SWAT. The parameter values on water stress, nitrogen stress were calibrated over global croplands from one grid cell to another (1.125° in latitude and longitude) using Markov Chain Monte Carlo (MCMC) methods. The historical yield data collected from major crop-producing countries on a state, county, or prefecture scale were used as the calibration data. Then we obtained the model parameter sets that can give high correlation coefficients between the historical and estimated yield time series for the period 1980-2006. We analyzed the impacts on soybean yields in the three top soybean-producing countries (the USA, China, and Brazil) associated with the changes in climate and CO2 during the period 1980-2006, using the model. We found that, given the simulated yields and reported harvested areas, the estimated average net benefit from the CO2 fertilization effect (with one standard deviation) in the USA, Brazil, and China in the years was 42.70×32.52 Mt, 35.30×28.55 Mt, and 12.52×15.11 Mt, respectively. Results suggest that the CO2-induced increases in soybean yields in the USA and China likely offset a part of the negative impacts on yields due to the historical temperature rise. In contrast, the net effect of the past change in climate and CO2 in Brazil appeared to be positive. This study demonstrates a quantitative estimation of the impacts of the changes
A direct correlation of x-ray diffraction orientation distributions to the in-plane stiffness of semi-crystalline organic semiconducting films

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

Zhao, Bingxiao; Awartani, Omar; O'Connor, Brendan

2016-05-02

Large charge mobilities of semi-crystalline organic semiconducting films could be obtained by mechanically aligning the material phases of the film with the loading axis. A key element is to utilize the inherent stiffness of the material for optimal or desired alignment. However, experimentally determining the moduli of semi-crystalline organic thin films for different loading directions is difficult, if not impossible, due to film thickness and material anisotropy. In this paper, we address these challenges by presenting an approach based on combining a composite mechanics stiffness orientation formulation with a Gaussian statistical distribution to directly estimate the in-plane stiffness (transverse isotropy)more » of aligned semi-crystalline polymer films based on crystalline orientation distributions obtained by X-ray diffraction experimentally at different applied strains. Our predicted results indicate that the in-plane stiffness of an annealing film was initially isotropic, and then it evolved to transverse isotropy with increasing mechanical strains. This study underscores the significance of accounting for the crystalline orientation distributions of the film to obtain an accurate understanding and prediction of the elastic anisotropy of semi-crystalline polymer films.« less
Off-axis illumination direct-to-digital holography

DOEpatents

Thomas, Clarence E.; Price, Jeffery R.; Voelkl, Edgar; Hanson, Gregory R.

2004-06-08

Systems and methods are described for off-axis illumination direct-to-digital holography. A method of recording an off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis, includes: reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object at an angle with respect to an optical axis defined by a focusing lens; focusing the reference beam and the object beam at a focal plane of a digital recorder to form the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digitally recording the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; Fourier analyzing the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes by transforming axes of the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined as an angle between the reference beam and the object beam; applying a digital filter to cut off signals around an original origin; and then performing an inverse Fourier transform.
Validity and sensitivity to change of the semi-quantitative OMERACT ultrasound scoring system for tenosynovitis in patients with rheumatoid arthritis.

PubMed

Ammitzbøll-Danielsen, Mads; Østergaard, Mikkel; Naredo, Esperanza; Terslev, Lene

2016-12-01

The aim was to evaluate the metric properties of the semi-quantitative OMERACT US scoring system vs a novel quantitative US scoring system for tenosynovitis, by testing its intra- and inter-reader reliability, sensitivity to change and comparison with clinical tenosynovitis scoring in a 6-month follow-up study. US and clinical assessments of the tendon sheaths of the clinically most affected hand and foot were performed at baseline, 3 and 6 months in 51 patients with RA. Tenosynovitis was assessed using the semi-quantitative scoring system (0-3) proposed by the OMERACT US group and a new quantitative US evaluation (0-100). A sum for US grey scale (GS), colour Doppler (CD) and pixel index (PI), respectively, was calculated for each patient. In 20 patients, intra- and inter-observer agreement was established between two independent investigators. A binary clinical tenosynovitis score was performed, calculating a sum score per patient. The intra- and inter-observer agreements for US tenosynovitis assessments were very good at baseline and for change for GS and CD, but less good for PI. The smallest detectable change was 0.97 for GS, 0.93 for CD and 30.1 for PI. The sensitivity to change from month 0 to 6 was high for GS and CD, and slightly higher than for clinical tenosynovitis score and PI. This study demonstrated an excellent intra- and inter-reader agreement between two investigators for the OMERACT US scoring system for tenosynovitis and a high ability to detect changes over time. Quantitative assessment by PI did not add further information. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Time-dependent inhibitory effects of Tris(1, 3-dichloro-2-propyl) phosphate on growth and transcription of genes involved in the GH/IGF axis, but not the HPT axis, in female zebrafish.

PubMed

Zhu, Ya; Su, Guanyong; Yang, Dandong; Zhang, Yongkang; Yu, Liqin; Li, Yufei; Giesy, John P; Letcher, Robert J; Liu, Chunsheng

2017-10-01

Growth curves were used to determine sensitive exposure windows for evaluation of developmental toxicity of chemicals to zebrafish. Dose- and time-dependent effects on body mass, body length and expression of genes involved in the growth hormone/insulin-like growth factor (GH/IGF) axis and the hypothalamic-pituitary-thyroid (HPT) axis were examined after exposure to environmentally relevant concentrations of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP). Based on growth curves, zebrafish grew most rapidly between 60 and 90 days post fertilization (dpf). Exposure to environmentally relevant concentrations of TDCIPP significantly decreased body mass and body length and down-regulated expression of several genes involved in the GH/IGF axis of female zebrafish, but no such effects were observed in male zebrafish. Exposure to TDCIPP did not change concentrations of thyroid hormones or expression of genes along the HPT axis in female and male zebrafish. These results suggest that growth stages of zebrafish between 60 and 90 dpf might be most appropriate for evaluation of developmental toxicity of chemicals, and down-regulation of genes involved in the GH/IGF axis, but not the HPT axis, might be responsible for the observed growth inhibition in females exposed to TDCIPP. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sacroplasty procedural extravasation with high viscosity bone cement: comparing the intraoperative long-axis versus short-axis techniques in osteoporotic cadavers.

PubMed

Miller, Jeffrey W; Diani, Art; Docsa, Steve; Ashton, Kristi; Sciamanna, Michele

2017-09-01

Percutaneous sacroplasty involves image-guided injection of bone cement for sacral insufficiency fractures to alleviate pain and facilitate mobility. Correct sacral placement of the cement and the risk of cement extravasation present procedural challenges. This study compares the occurrence, number, location, and surface area of high viscosity radiopaque bone cement extravasation via biplane fluoroscopy with Dyna CT between the fluoroscopically-guided intraoperative long-axis and short-axis sacroplasty techniques in osteoporotic cadavers. Ten osteoporotic cadavers underwent bilateral percutaneous instillation of VertaPlex HV High Viscosity Radiopaque Bone Cement. Long- and short-axis sacroplasty techniques were randomly assigned to zone 1 of the left or right sacral ala of each cadaver. Cement extravasation data were summarized by technique (long-axis vs short-axis) and time period (15-min and 3-hour post-procedure syngo DynaCT scan) in the form of point and CI estimates for the true proportions of cement extravasation. No procedural sacral extravasation differences were observed between the long-axis and short-axis sacroplasty techniques. There were no occurrences of intra-procedural or post-procedural cement extravasation at 15 min or 3 hours in association with either the long-axis sacroplasty technique or the short-axis sacroplasty technique. The long- and short-axis sacroplasty techniques, using high viscosity cement with careful post-procedural positioning, result in no occurrence of cement extravasation in porous osteoporotic cadaver bone. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Resonant obliquity of Mars?. [climate driven by spin axis and orbit plane precession caused oscillations

NASA Technical Reports Server (NTRS)

Ward, William R.; Rudy, Donald J.

1991-01-01

The large-scale oscillations generated by the obliquity of Mars through spin-axis and orbit-plane precessions constitute basic climate system drivers with periodicities of 100,000 yrs in differential spin axis-orbit precession rates and of over 1 million yrs in amplitude modulations due to orbital-inclination changes. Attention is presently given to a third time-scale for climate change, which involves a possible spin-spin resonance and whose mechanism operates on a 10-million-yr time-scale: this effect implies an average obliquity increase for Mars of 15 deg only 5 million yrs ago, with important climatic consequences.
Crystallographic orientation of the c-axis of biological apatite as a new index of the quality of subchondral bone in knee joint osteoarthritis.

PubMed

Lee, Jee-Wook; Kobayashi, Akio; Nakano, Takayoshi

2017-05-01

The aim of the present study was to investigate the preferred orientation of biological apatite (BAp) as a new index of the quality of subchondral bone (SB) in knee joint osteoarthritis (OA). Ten OA and five normal knee joints were obtained. Thickness, quantity and bone mineral density (BMD) of SB were analyzed at the medial condyle of the femur in dry conditions by peripheral quantitative computed tomography. In addition, the preferred crystallographic orientation of the c-axis of BAp was evaluated as bone quality parameter using a microbeam X-ray diffractometer technique. BMD and thickness of SB were significantly increased in OA specimens compared to normal knee specimens (P < 0.01), and the preferred orientation of the c-axis of BAp along the normal direction of SB surface was significantly higher in OA specimens (P < 0.01), reflecting the change in stress of concentration in the pathological portion without cartilage. SB sclerosis in OA results in both proliferation of bone tissues and enhanced degree of preferential alignment of the c-axis of BAp. Our findings could have major implications for the diagnosis of clinical studies, including pathologic elucidation in OA.
Potential Signatures of Semi-volatile Compounds Associated With Nuclear Processing

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

Probasco, Kathleen M.; Birnbaum, Jerome C.; Maughan, A. D.

2002-06-01

Semi-volatile chemicals associated with nuclear processes (e.g., the reprocessing of uranium to produce plutonium for nuclear weapons, or the separation of actinides from processing waste streams), can provide sticky residues or signatures that will attach to piping, ducting, soil, water, or other surface media. Volatile compounds, that are more suitable for electro-optical sensing, have been well studied. However, the semi-volatile compounds have not been well documented or studied. A majority of these semi-volatile chemicals are more robust than typical gaseous or liquid chemicals and can have lifetimes of several weeks, months, or years in the environment. However, large data gapsmore » exist concerning these potential signature compounds and more research is needed to fill these data gaps so that important signature information is not overlooked or discarded. This report investigates key semi-volatile compounds associated with nuclear separations, identifies available chemical and physical properties, and discusses the degradation products that would result from hydrolysis, radiolysis and oxidation reactions on these compounds.« less
Optic axis determination accuracy for fiber-based polarization-sensitive optical coherence tomography.

PubMed

Park, B Hyle; Pierce, Mark C; Cense, Barry; de Boer, Johannes F

2005-10-01

We present a generalized analysis of fiber-based polarization-sensitive optical coherence tomography with an emphasis on determination of sample optic axis orientation. The polarization properties of a fiber-based system can cause an overall rotation in a Poincaré sphere representation such that the plane of possible measured sample optic axes for linear birefringence and diattenuation no longer lies in the QU-plane. The optic axis orientation can be recovered as an angle on this rotated plane, subject to an offset and overall indeterminacy in sign such that only the magnitude, but not the direction, of a change in orientation can be determined. We discuss the accuracy of optic axis determination due to a fundamental limit on the accuracy with which a polarization state can be determined as a function of signal-to-noise ratio.
Effects of selective serotonin reuptake inhibitor treatment on plasma oxytocin and cortisol in major depressive disorder.

PubMed

Keating, Charlotte; Dawood, Tye; Barton, David A; Lambert, Gavin W; Tilbrook, Alan J

2013-04-29

Oxytocin is known for its capacity to facilitate social bonding, reduce anxiety and for its actions on the stress hypothalamopituitary adrenal (HPA) axis. Since oxytocin can physiologically suppress activity of the HPA axis, clinical applications of this neuropeptide have been proposed in conditions where the function of the HPA axis is dysregulated. One such condition is major depressive disorder (MDD). Dysregulation of the HPA system is the most prominent endocrine change seen with MDD, and normalizing the HPA axis is one of the major targets of recent treatments. The potential clinical application of oxytocin in MDD requires improved understanding of its relationship to the symptoms and underlying pathophysiology of MDD. Previous research has investigated potential correlations between oxytocin and symptoms of MDD, including a link between oxytocin and treatment related symptom reduction. The outcomes of studies investigating whether antidepressive treatment (pharmacological and non-pharmacological) influences oxytocin concentrations in MDD, have produced conflicting outcomes. These outcomes suggest the need for an investigation of the influence of a single treatment class on oxytocin concentrations, to determine whether there is a relationship between oxytocin, the HPA axis (e.g., oxytocin and cortisol) and MDD. Our objective was to measure oxytocin and cortisol in patients with MDD before and following treatment with selective serotonin reuptake inhibitors, SSRI. We sampled blood from arterial plasma. Patients with MDD were studied at the same time twice; pre- and post- 12 weeks treatment, in an unblinded sequential design (clinicaltrials.govNCT00168493). Results did not reveal differences in oxytocin or cortisol concentrations before relative to following SSRI treatment, and there were no significant relationships between oxytocin and cortisol, or these two physiological variables and psychological symptom scores, before or after treatment. These outcomes
Impacts of climate change on trends in baseflow and stormflow in major watersheds of China

NASA Astrophysics Data System (ADS)

Wang, L.

2017-12-01

Impacts of climate change on trends in baseflow and stormflow in major watersheds of ChinaLijun Wang1, Fuqiang Tian1*, Hongchang Hu11State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, China,Abstracts: During the past 50 years, runoff from the major watersheds in China has demonstrated a decrease trend. The variations in the amount of precipitation will directly influence the runoff, however in some parts of China, it is also found that there is huge variations in the amount of runoff whereas the amount of precipitation has not shown such variations. In the same time, the intensity and duration of rainfall has changed a lot. Therefore, it is important to categorize the different trends of runoff and to identify the major factors responsible for these changes. In this study, we have collected the data of 200 different locations from 8 major watersheds of China. By comparing and analyzing the daily precipitation and the daily runoff data, we have found some significant changes in runoff coefficients between two periods (1979-1988 and 2006-2014). On the basis of this, the further study will be carried out which identify that how the climate change influences the two major components of runoff, baseflow and stormflow. The impact of anthropogenic activity in the study area could not be ignored and it is important to know whether human action and climate change is the main factors for the decline of waterflow in river and how these factors influence the river water.
Vertical axis wind turbine airfoil

DOEpatents

Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

2012-12-18

A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.
Modular off-axis solar concentrator

DOEpatents

Plesniak, Adam P; Hall, John C

2015-01-27

A solar concentrator including a housing defining a vertical axis and including a receiving wall connected to a reflecting wall to define an internal volume and an opening into the internal volume, wherein the reflecting wall defines at least one primary optical element, and wherein at least a portion of the reflecting wall includes a layer of reflective material, the housing further including a cover connected to the receiving wall and the reflecting wall to seal the opening, and at least one receiver mounted on the receiving wall such that a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, the receiver including at least one photovoltaic cell.
Is Dysregulation of the HPA-Axis a Core Pathophysiology Mediating Co-Morbid Depression in Neurodegenerative Diseases?

PubMed Central

Du, Xin; Pang, Terence Y.

2015-01-01

There is increasing evidence of prodromal manifestation of neuropsychiatric symptoms in a variety of neurodegenerative diseases such as Parkinson’s disease (PD) and Huntington’s disease (HD). These affective symptoms may be observed many years before the core diagnostic symptoms of the neurological condition. It is becoming more apparent that depression is a significant modifying factor of the trajectory of disease progression and even treatment outcomes. It is therefore crucial that we understand the potential pathophysiologies related to the primary condition, which could contribute to the development of depression. The hypothalamic–pituitary–adrenal (HPA)-axis is a key neuroendocrine signaling system involved in physiological homeostasis and stress response. Disturbances of this system lead to severe hormonal imbalances, and the majority of such patients also present with behavioral deficits and/or mood disorders. Dysregulation of the HPA-axis is also strongly implicated in the pathology of major depressive disorder. Consistent with this, antidepressant drugs, such as the selective serotonin reuptake inhibitors have been shown to alter HPA-axis activity. In this review, we will summarize the current state of knowledge regarding HPA-axis pathology in Alzheimer’s, PD and HD, differentiating between prodromal and later stages of disease progression when evidence is available. Both clinical and preclinical evidence will be examined, but we highlight animal model studies as being particularly useful for uncovering novel mechanisms of pathology related to co-morbid mood disorders. Finally, we purpose utilizing the preclinical evidence to better inform prospective, intervention studies. PMID:25806005
Major Mergers in CANDELS up to z=3: Calibrating the Close-Pair Method Using Semi-Analytic Models and Baryonic Mass Ratio Estimates

NASA Astrophysics Data System (ADS)

Mantha, Kameswara; McIntosh, Daniel H.; Conselice, Christopher; Cook, Joshua S.; Croton, Darren J.; Dekel, Avishai; Ferguson, Henry C.; Hathi, Nimish; Kodra, Dritan; Koo, David C.; Lotz, Jennifer M.; Newman, Jeffrey A.; Popping, Gergo; Rafelski, Marc; Rodriguez-Gomez, Vicente; Simmons, Brooke D.; Somerville, Rachel; Straughn, Amber N.; Snyder, Gregory; Wuyts, Stijn; Yu, Lu; Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) Team

2018-01-01

Cosmological simulations predict that the rate of merging between similar-mass massive galaxies should increase towards early cosmic-time. We study the incidence of major (stellar mass ratio SMR<4) close-pairs among log(Mstellar/Msun) > 10.3 galaxies spanning 0major merger rates diminish with increasing redshift at z>1.5 in strong disagreement with theoretical merger rate predictions. On the other hand, if we compare to a simulation-tuned, evolving timescale prescription from Snyder et al., 2017, we find that the merger rate evolution agrees with theory out to z=3. These results highlight the need for robust calibrations on the complex and presumably redshift-dependent pair-to-merger-rate conversion factors to improve constraints of the empirical merger history. To address this, we use a unique compilation of mock datasets produced by three independent state-of-the-art Semi-Analytic Models (SAMs). We present preliminary calibrations of the close-pair observability timescale and outlier fraction as a function of redshift, stellar-mass, mass-ratio, and local over-density. Furthermore, to verify the hypothesis by previous empirical studies that SMR-selection of major pairs may be biased, we present a new analysis of the baryonic (gas+stars) mass ratios of a subset of close pairs in our sample. For the first time, our preliminary analysis highlights that a noticeable fraction of SMR-selected minor pairs (SMR>4) have major baryonic-mass ratios (BMR<4), which indicate that merger rates based on SMR selection may be under-estimated.
Semi-supervised learning via regularized boosting working on multiple semi-supervised assumptions.

PubMed

Chen, Ke; Wang, Shihai

2011-01-01

Semi-supervised learning concerns the problem of learning in the presence of labeled and unlabeled data. Several boosting algorithms have been extended to semi-supervised learning with various strategies. To our knowledge, however, none of them takes all three semi-supervised assumptions, i.e., smoothness, cluster, and manifold assumptions, together into account during boosting learning. In this paper, we propose a novel cost functional consisting of the margin cost on labeled data and the regularization penalty on unlabeled data based on three fundamental semi-supervised assumptions. Thus, minimizing our proposed cost functional with a greedy yet stagewise functional optimization procedure leads to a generic boosting framework for semi-supervised learning. Extensive experiments demonstrate that our algorithm yields favorite results for benchmark and real-world classification tasks in comparison to state-of-the-art semi-supervised learning algorithms, including newly developed boosting algorithms. Finally, we discuss relevant issues and relate our algorithm to the previous work.
Straightforward Method for Coverage of Major Vessels After Modified Radical Neck Dissection.

PubMed

González-García, Raúl; Moreno-García, Carlos; Moreno-Sánchez, Manuel; Román-Romero, Leticia

2017-06-01

A new method for covering the internal jugular vein and carotid artery after exposure of the cervical vascular axis subsequent to neck dissection is presented. To cover the most caudal part of the vascular axis, a platysma coli muscle flap is harvested from its most medial and inferior part of the neck in a caudally based fashion and is slightly rotated posteriorly up to 45°. In addition, a superiorly based sternocleidomastoid muscle flap involving the posterior half of the muscle after detachment of the clavicle head is harvested and rotated 45° anteriorly to cover the upper two thirds of the vascular axis. This technique seems to be a good alternative to the pectoralis major myocutaneous flap for covering cervical major vessels, if no classical radical neck dissection is performed, especially in those oncologic malnourished patients who will undergo adjuvant radiotherapy after surgical treatment. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Hydrologic Connectivity: a Framework to Understand Threshold Behaviour in Semi-Arid Landscapes.

NASA Astrophysics Data System (ADS)

Saco, Patricia; Rodriguez, Jose; Keesstra, Saskia; Moreno-de las Heras, Mariano; Sandi, Steven; Baartman, Jantiene; Cerdà, Artemi

2017-04-01

Anthropogenic activities and climate change are imposing an unprecedented pressure on arid and semi-arid ecosystems, where shortage of water can trigger shifts in landscapes' structures and function leading to degradation and desertification. Hydrological connectivity is a useful framework for understanding water redistribution and scaling issues associated to runoff and sediment production, since human and/or natural disturbances alter the surface water availability and pathways increasing/decreasing connectivity. In this presentation, we illustrate the use of the connectivity framework for several examples of dryland systems that are analysed at a variety of spatial and temporal scales. In doing so, we draw particular attention to the analysis of co-evolution of system structures and function, and how they drive threshold behaviour leading to desertification and degradation. We first analyse the case of semi-arid rangelands, where feedbacks between decline in vegetation density and landscape erosion reinforces degradation processes driven by changes in connectivity until a threshold is crossed above which the return to a functional system is unlikely. We then focus on semi-arid wetlands, where decreases in water volumes promotes dryland vegetation encroachment that changes drainage conditions and connectivity potentially reinforcing redistribution of flow paths to other wetland areas. The examples presented highlight the need to incorporate a co-evolutionary framework for the analysis of changing connectivity patterns and the emergence of thresholds in arid and semi-arid systems.
Targeting the IL-33/IL-13 Axis for Respiratory Viral Infections.

PubMed

Donovan, Chantal; Bourke, Jane E; Vlahos, Ross

2016-04-01

Lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are highly prevalent worldwide. One of the major factors that limits the efficacy of current medication in these patients are viral infections, leading to exacerbations of symptoms and decreased quality of life. Current pharmacological strategies targeting virus-induced lung disease are problematic due to antiviral resistance and the requirement for strain-specific vaccination. Thus, new therapeutic strategies are urgently required. In this Opinion article, we provide state-of-the-art evidence from humans and preclinical animal models implicating the interleukin (IL)-33/IL-13 axis in virus-induced lung disease. Thus, targeting the IL-33/IL-13 axis may be a feasible way to overcome the limitations of current therapy used to treat virus-induced exacerbations of lung disease. Copyright © 2016 Elsevier Ltd. All rights reserved.
Distribution of Particles in the Z-axis of Tissue Sections: Relevance for Counting Methods.

PubMed

von Bartheld, Christopher S

2012-01-01

The distribution of particles in the z-axis of thick tissue sections has gained considerable attention, primarily because of implications for the accuracy of modern stereological counting methods. Three major types of artifacts can affect these sections: loss of particles from the surfaces of tissue sections (lost caps), homogeneous collapse in the z-axis, and differential deformation in the z-axis. Initially it was assumed that thick sections were not compromised by differential shrinkage or compression (differential uniform deformation). Studies in the last decade showed that such artifacts are common and that they depend on embedding media and sectioning devices. Paraffin, glycolmethacrylate and vibratome sections are affected by this artifact, but not celloidin sections or cryostat-derived cryosections. Differential distribution of particles in the z-axis is likely due to compression of the surface areas (margins) during sectioning, resulting in differential particle densities in the core and margin of tissue sections. This deformation of tissue sections can be rapidly assessed by measuring the position of particles in the z-axis. The analysis is complicated by potential secondary effects on section surfaces through loss of particles, the so-called "lost caps" phenomenon. Secondary effects necessitate the use of guard spaces, while their use in case of primary effects (compression due to sectioning) would enhance the artifact's impact on bias. Symmetric versus asymmetric patterns of z-axis distortion can give clues to distinguish primary and secondary effects. Studies that use the optical disector need to take these parameters into account to minimize biases.
Changes to Workflow and Process Measures in the PICU During Transition From Semi to Full Electronic Health Record.

PubMed

Salib, Mina; Hoffmann, Raymond G; Dasgupta, Mahua; Zimmerman, Haydee; Hanson, Sheila

2015-10-01

Studies showing the changes in workflow during transition from semi to full electronic medical records are lacking. This objective study is to identify the changes in workflow in the PICU during transition from semi to full electronic health record. Prospective observational study. Children's Hospital of Wisconsin Institutional Review Board waived the need for approval so this study was institutional review board exempt. This study measured clinical workflow variables at a 72-bed PICU during different phases of transition to a full electronic health record, which occurred on November 4, 2012. Phases of electronic health record transition were defined as follows: pre-electronic health record (baseline data prior to transition to full electronic health record), transition phase (3 wk after electronic health record), and stabilization (6 mo after electronic health record). Data were analyzed for the three phases using Mann-Whitney U test with a two-sided p value of less than 0.05 considered significant. Seventy-two bed PICU. All patients in the PICU were included during the study periods. Five hundred and sixty-four patients with 2,355 patient days were evaluated in the three phases. Duration of rounds decreased from a median of 9 minutes per patient pre--electronic health record to 7 minutes per patient post electronic health record. Time to final note decreased from 2.06 days pre--electronic health record to 0.5 days post electronic health record. Time to first medication administration after admission also decreased from 33 minutes pre--electronic health record and 7 minutes post electronic health record. Time to Time to medication reconciliation was significantly higher pre-electronic health record than post electronic health record and percent of medication reconciliation completion was significantly lower pre--electronic health record than post electronic health record and percent of medication reconciliation completion was significantly higher pre
Altered Regulation of Gene and Protein Expression of Hypothalamic-Pituitary-Adrenal Axis Components in an Immature Rat Model of Chronic Stress

PubMed Central

Avishai-Eliner, S.; Gilles, E. E.; Eghbal-Ahmadi, M.; Bar-El, Y.; Baram, T. Z.

2011-01-01

Chronic stress early in postnatal life influences hormonal and behavioural responses to stress persistently, but the mechanisms and molecular cascades that are involved in this process have not been clarified. To approach these issues, a chronic stress paradigm for the neonatal rat, using limited bedding material to alter the cage environment, was devised. In 9-day-old rats subjected to this chronic stress for 1 week, significant and striking changes in the expression and release patterns of key molecules that govern the neuroendocrine stress responses were observed. The presence of sustained stress was evident from enhanced activation of peripheral elements of the neuroendocrine stress response, i.e. increased basal plasma corticosterone concentrations, high adrenal weight and decreased body weight. Central regulatory elements of the neuroendocrine stress response were perturbed, including reduced expression of hypothalamic corticotropin-releasing hormone that, surprisingly, was accompanied by reduced glucocorticoid receptor expression. Thus, the effects of chronic sustained stress in the neonatal rat on the hypothalamic-pituitary-adrenal axis included substantial changes in the expression and activity of major regulators of this axis. Importantly, the changes induced by this chronic stress differed substantially from those related to acute or recurrent stress, providing a novel model for studying the long-term effects of chronic, early life stress on neuroendocrine functions throughout life. PMID:11578530
Low Lunar Orbit Design via Graphical Manipulation of Eccentricity Vector Evolution

NASA Technical Reports Server (NTRS)

Wallace, Mark S.; Sweetser, Theodore H.; Roncoli, Ralph B.

2012-01-01

Low lunar orbits, such as those used by GRAIL and LRO, experience predictable variations in the evolution of their eccentricity vectors. These variations are nearly invariant with respect to the initial eccentricity and argument of periapse and change only in the details with respect to the initial semi-major axis. These properties suggest that manipulating the eccentricity vector evolution directly can give insight into orbit maintenance designs and can reduce the number of propagations required. A trio of techniques for determining the desired maneuvers is presented in the context of the GRAIL extended mission.

Testing the Definition of the ESC Envelope

NASA Technical Reports Server (NTRS)

Vincent, Mark A.

2017-01-01

The previous effort, including a successful Change Control Request, addressed shrinking the size of the Earth Science Constellations' (ESC) Envelope by reducing the Margin. Fundamental to the purpose of the Envelope is the case where the argument of perigee of the secondary object circulates from 90 degrees to 270 degrees. This ("outside of the envelope, always outside the envelope") case was tested both numerically in a spreadsheet and analytically. Results showed how it is important to include the fact that a secondary with a different semi-major axis has a different frozen eccentricity value.
Distortion definition and correction in off-axis systems

NASA Astrophysics Data System (ADS)

Da Deppo, Vania; Simioni, Emanuele; Naletto, Giampiero; Cremonese, Gabriele

2015-09-01

Off-axis optical configurations are becoming more and more used in a variety of applications, in particular they are the most preferred solution for cameras devoted to Solar System planets and small bodies (i.e. asteroids and comets) study. Off-axis designs, being devoid of central obstruction, are able to guarantee better PSF and MTF performance, and thus higher contrast imaging capabilities with respect to classical on-axis designs. In particular they are suitable for observing extended targets with intrinsic low contrast features, or scenes where a high dynamical signal range is present. Classical distortion theory is able to well describe the performance of the on-axis systems, but it has to be adapted for the off-axis case. A proper way to deal with off-axis distortion definition is thus needed together with dedicated techniques to accurately measure and hence remove the distortion effects present in the acquired images. In this paper, a review of the distortion definition for off-axis systems will be given. In particular the method adopted by the authors to deal with the distortion related issues (definition, measure, removal) in some off-axis instruments will be described in detail.
Three-Axis Time-Optimal Attitude Maneuvers of a Rigid-Body

NASA Astrophysics Data System (ADS)

Wang, Xijing; Li, Jisheng

With the development trends for modern satellites towards macro-scale and micro-scale, new demands are requested for its attitude adjustment. Precise pointing control and rapid maneuvering capabilities have long been part of many space missions. While the development of computer technology enables new optimal algorithms being used continuously, a powerful tool for solving problem is provided. Many papers about attitude adjustment have been published, the configurations of the spacecraft are considered rigid body with flexible parts or gyrostate-type systems. The object function always include minimum time or minimum fuel. During earlier satellite missions, the attitude acquisition was achieved by using the momentum ex change devices, performed by a sequential single-axis slewing strategy. Recently, the simultaneous three-axis minimum-time maneuver(reorientation) problems have been studied by many researchers. It is important to research the minimum-time maneuver of a rigid spacecraft within onboard power limits, because of potential space application such as surveying multiple targets in space and academic value. The minimum-time maneuver of a rigid spacecraft is a basic problem because the solutions for maneuvering flexible spacecraft are based on the solution to the rigid body slew problem. A new method for the open-loop solution for a rigid spacecraft maneuver is presented. Having neglected all perturbation torque, the necessary conditions of spacecraft from one state to another state can be determined. There is difference between single-axis with multi-axis. For single- axis analytical solution is possible and the switching line passing through the state-space origin belongs to parabolic. For multi-axis, it is impossible to get analytical solution due to the dynamic coupling between the axes and must be solved numerically. Proved by modern research, Euler axis rotations are quasi-time-optimal in general. On the basis of minimum value principles, a research for
Model-Based Therapeutic Correction of Hypothalamic-Pituitary-Adrenal Axis Dysfunction

PubMed Central

Ben-Zvi, Amos; Vernon, Suzanne D.; Broderick, Gordon

2009-01-01

The hypothalamic-pituitary-adrenal (HPA) axis is a major system maintaining body homeostasis by regulating the neuroendocrine and sympathetic nervous systems as well modulating immune function. Recent work has shown that the complex dynamics of this system accommodate several stable steady states, one of which corresponds to the hypocortisol state observed in patients with chronic fatigue syndrome (CFS). At present these dynamics are not formally considered in the development of treatment strategies. Here we use model-based predictive control (MPC) methodology to estimate robust treatment courses for displacing the HPA axis from an abnormal hypocortisol steady state back to a healthy cortisol level. This approach was applied to a recent model of HPA axis dynamics incorporating glucocorticoid receptor kinetics. A candidate treatment that displays robust properties in the face of significant biological variability and measurement uncertainty requires that cortisol be further suppressed for a short period until adrenocorticotropic hormone levels exceed 30% of baseline. Treatment may then be discontinued, and the HPA axis will naturally progress to a stable attractor defined by normal hormone levels. Suppression of biologically available cortisol may be achieved through the use of binding proteins such as CBG and certain metabolizing enzymes, thus offering possible avenues for deployment in a clinical setting. Treatment strategies can therefore be designed that maximally exploit system dynamics to provide a robust response to treatment and ensure a positive outcome over a wide range of conditions. Perhaps most importantly, a treatment course involving further reduction in cortisol, even transient, is quite counterintuitive and challenges the conventional strategy of supplementing cortisol levels, an approach based on steady-state reasoning. PMID:19165314
Actuator assembly including a single axis of rotation locking member

DOEpatents

Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

2009-12-08

An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.
Left-right axis asymmetry determining human Cryptic gene is transcriptionally repressed by Snail.

PubMed

Gupta, Kartik; Pilli, Vijaya Satish Sekhar; Aradhyam, Gopala Krishna

2016-10-28

Establishment of the left-right axis is important for positioning organs asymmetrically in the developing vertebrate-embryo. A number of factors like maternally deposited molecules have emerged essential in initiating the specification of the axis; the downstream events, however, are regulated by signal-transduction and gene-expression changes identifying which remains a crucial challenge. The EGF-CFC family member Cryptic, that functions as a co-receptor for some TGF-beta ligands, is developmentally expressed in higher mammals and mutations in the gene cause loss or change in left-right axis asymmetry. Despite the strong phenotype, no transcriptional-regulator of this gene is known till date. Using promoter-analyses tools, we found strong evidence that the developmentally essential transcription factor Snail binds to the human Cryptic-promoter. We cloned the promoter-region of human Cryptic in a reporter gene and observed decreased Cryptic-promoter activation upon increasing Snail expression. Further, the expression of Cryptic is down-regulated upon exogenous Snail expression, validating the reporter assays and the previously identified role of Snail as a transcriptional repressor. Finally, we demonstrate using gel-shift assay that Snail in nuclear extract of PANC1 cells interacts with the promoter-construct bearing putative Snail binding sites and confirm this finding using chromatin immunoprecipitation assay. Snail represses the expression of human Cryptic and therefore, might affect the signaling via Nodal that has previously been demonstrated to specify the left-right axis using the EGF-CFC co-receptors.
Structural basis for the facilitative diffusion mechanism by SemiSWEET transporter

NASA Astrophysics Data System (ADS)

Lee, Yongchan; Nishizawa, Tomohiro; Yamashita, Keitaro; Ishitani, Ryuichiro; Nureki, Osamu

2015-01-01

SWEET family proteins mediate sugar transport across biological membranes and play crucial roles in plants and animals. The SWEETs and their bacterial homologues, the SemiSWEETs, are related to the PQ-loop family, which is characterized by highly conserved proline and glutamine residues (PQ-loop motif). Although the structures of the bacterial SemiSWEETs were recently reported, the conformational transition and the significance of the conserved motif in the transport cycle have remained elusive. Here we report crystal structures of SemiSWEET from Escherichia coli, in the both inward-open and outward-open states. A structural comparison revealed that SemiSWEET undergoes an intramolecular conformational change in each protomer. The conserved PQ-loop motif serves as a molecular hinge that enables the ‘binder clip-like’ motion of SemiSWEET. The present work provides the framework for understanding the overall transport cycles of SWEET and PQ-loop family proteins.
Effect of Relative Marker Movement on the Calculation of the Foot Torsion Axis Using a Combined Cardan Angle and Helical Axis Approach

PubMed Central

Graf, Eveline S.; Wright, Ian C.; Stefanyshyn, Darren J.

2012-01-01

The two main movements occurring between the forefoot and rearfoot segment of a human foot are flexion at the metatarsophalangeal joints and torsion in the midfoot. The location of the torsion axis within the foot is currently unknown. The purpose of this study was to develop a method based on Cardan angles and the finite helical axis approach to calculate the torsion axis without the effect of flexion. As the finite helical axis method is susceptible to error due to noise with small helical rotations, a minimal amount of rotation was defined in order to accurately determine the torsion axis location. Using simulation, the location of the axis based on data containing noise was compared to the axis location of data without noise with a one-sample t-test and Fisher's combined probability score. When using only data with helical rotation of seven degrees or more, the location of the torsion axis based on the data with noise was within 0.2 mm of the reference location. Therefore, the proposed method allowed an accurate calculation of the foot torsion axis location. PMID:22666303
The influence of image setting on intracranial translucency measurement by manual and semi-automated system.

PubMed

Zhen, Li; Yang, Xin; Ting, Yuen Ha; Chen, Min; Leung, Tak Yeung

2013-09-01

To investigate the agreement between manual and semi-automated system and the effect of different image settings on intracranial translucency (IT) measurement. A prospective study was conducted on 55 women carrying singleton pregnancy who attended first trimester Down syndrome screening. IT was measured both manually and by semi-automated system at the same default image setting. The IT measurements were then repeated with the post-processing changes in the image setting one at a time. The difference in IT measurements between the altered and the original images were assessed. Intracranial translucency was successfully measured on 55 images both manually and by semi-automated method. There was strong agreement in IT measurements between the two methods with a mean difference (manual minus semi-automated) of 0.011 mm (95% confidence interval--0.052 mm-0.094 mm). There were statistically significant variations in both manual and semi-automated IT measurement after changing the Gain and the Contrast. The greatest changes occurred when the Contrast was reduced to 1 (IT reduced by 0.591 mm in semi-automated; 0.565 mm in manual), followed by when the Gain was increased to 15 (IT reduced by 0.424 mm in semi-automated; 0.524 mm in manual). The image settings may affect IT identification and measurement. Increased Gain and reduced Contrast are the most influential factors and may cause under-measurement of IT. © 2013 John Wiley & Sons, Ltd.
HPA AXIS RELATED GENES AND RESPONSE TO PSYCHOLOGICAL THERAPIES: GENETICS AND EPIGENETICS

PubMed Central

Roberts, Susanna; Keers, Robert; Lester, Kathryn J; Coleman, Jonathan R. I.; Breen, Gerome; Arendt, Kristian; Blatter‐Meunier, Judith; Cooper, Peter; Creswell, Cathy; Fjermestad, Krister; Havik, Odd E.; Herren, Chantal; Hogendoorn, Sanne M.; Hudson, Jennifer L.; Krause, Karen; Lyneham, Heidi J.; Morris, Talia; Nauta, Maaike; Rapee, Ronald M.; Rey, Yasmin; Schneider, Silvia; Schneider, Sophie C.; Silverman, Wendy K.; Thastum, Mikael; Thirlwall, Kerstin; Waite, Polly

2015-01-01

Background Hypothalamic–pituitary–adrenal (HPA) axis functioning has been implicated in the development of stress‐related psychiatric diagnoses and response to adverse life experiences. This study aimed to investigate the association between genetic and epigenetics in HPA axis and response to cognitive behavior therapy (CBT). Methods Children with anxiety disorders were recruited into the Genes for Treatment project (GxT, N = 1,152). Polymorphisms of FKBP5 and GR were analyzed for association with response to CBT. Percentage DNA methylation at the FKBP5 and GR promoter regions was measured before and after CBT in a subset (n = 98). Linear mixed effect models were used to investigate the relationship between genotype, DNA methylation, and change in primary anxiety disorder severity (treatment response). Results Treatment response was not associated with FKBP5 and GR polymorphisms, or pretreatment percentage DNA methylation. However, change in FKBP5 DNA methylation was nominally significantly associated with treatment response. Participants who demonstrated the greatest reduction in severity decreased in percentage DNA methylation during treatment, whereas those with little/no reduction in severity increased in percentage DNA methylation. This effect was driven by those with one or more FKBP5 risk alleles, with no association seen in those with no FKBP5 risk alleles. No significant association was found between GR methylation and response. Conclusions Allele‐specific change in FKBP5 methylation was associated with treatment response. This is the largest study to date investigating the role of HPA axis related genes in response to a psychological therapy. Furthermore, this is the first study to demonstrate that DNA methylation changes may be associated with response to psychological therapies in a genotype‐dependent manner. PMID:26647360
Two-axis angular effector

DOEpatents

Vaughn, Mark R.; Robinett, III, Rush D.; Phelan, John R.; Van Zuiden, Don M.

1997-01-21

A new class of coplanar two-axis angular effectors. These effectors combine a two-axis rotational joint analogous to a Cardan joint with linear actuators in a manner to produce a wider range of rotational motion about both axes defined by the joint. This new class of effectors also allows design of robotic manipulators having very high strength and efficiency. These effectors are particularly suited for remote operation in unknown surroundings, because of their extraordinary versatility. An immediate application is to the problems which arise in nuclear waste remediation.
A Saliency Guided Semi-Supervised Building Change Detection Method for High Resolution Remote Sensing Images

PubMed Central

Hou, Bin; Wang, Yunhong; Liu, Qingjie

2016-01-01

Characterizations of up to date information of the Earth’s surface are an important application providing insights to urban planning, resources monitoring and environmental studies. A large number of change detection (CD) methods have been developed to solve them by utilizing remote sensing (RS) images. The advent of high resolution (HR) remote sensing images further provides challenges to traditional CD methods and opportunities to object-based CD methods. While several kinds of geospatial objects are recognized, this manuscript mainly focuses on buildings. Specifically, we propose a novel automatic approach combining pixel-based strategies with object-based ones for detecting building changes with HR remote sensing images. A multiresolution contextual morphological transformation called extended morphological attribute profiles (EMAPs) allows the extraction of geometrical features related to the structures within the scene at different scales. Pixel-based post-classification is executed on EMAPs using hierarchical fuzzy clustering. Subsequently, the hierarchical fuzzy frequency vector histograms are formed based on the image-objects acquired by simple linear iterative clustering (SLIC) segmentation. Then, saliency and morphological building index (MBI) extracted on difference images are used to generate a pseudo training set. Ultimately, object-based semi-supervised classification is implemented on this training set by applying random forest (RF). Most of the important changes are detected by the proposed method in our experiments. This study was checked for effectiveness using visual evaluation and numerical evaluation. PMID:27618903
A Saliency Guided Semi-Supervised Building Change Detection Method for High Resolution Remote Sensing Images.

PubMed

Hou, Bin; Wang, Yunhong; Liu, Qingjie

2016-08-27

Characterizations of up to date information of the Earth's surface are an important application providing insights to urban planning, resources monitoring and environmental studies. A large number of change detection (CD) methods have been developed to solve them by utilizing remote sensing (RS) images. The advent of high resolution (HR) remote sensing images further provides challenges to traditional CD methods and opportunities to object-based CD methods. While several kinds of geospatial objects are recognized, this manuscript mainly focuses on buildings. Specifically, we propose a novel automatic approach combining pixel-based strategies with object-based ones for detecting building changes with HR remote sensing images. A multiresolution contextual morphological transformation called extended morphological attribute profiles (EMAPs) allows the extraction of geometrical features related to the structures within the scene at different scales. Pixel-based post-classification is executed on EMAPs using hierarchical fuzzy clustering. Subsequently, the hierarchical fuzzy frequency vector histograms are formed based on the image-objects acquired by simple linear iterative clustering (SLIC) segmentation. Then, saliency and morphological building index (MBI) extracted on difference images are used to generate a pseudo training set. Ultimately, object-based semi-supervised classification is implemented on this training set by applying random forest (RF). Most of the important changes are detected by the proposed method in our experiments. This study was checked for effectiveness using visual evaluation and numerical evaluation.
O-Acetylation of Arabidopsis Hemicellulose Xyloglucan Requires AXY4 or AXY4L, Proteins with a TBL and DUF231 Domain[W][OA

PubMed Central

Gille, Sascha; de Souza, Amancio; Xiong, Guangyan; Benz, Monique; Cheng, Kun; Schultink, Alex; Reca, Ida-Barbara; Pauly, Markus

2011-01-01

In an Arabidopsis thaliana forward genetic screen aimed at identifying mutants with altered structures of their hemicellulose xyloglucan (axy mutants) using oligosaccharide mass profiling, two nonallelic mutants (axy4-1 and axy4-2) that have a 20 to 35% reduction in xyloglucan O-acetylation were identified. Mapping of the mutation in axy4-1 identified AXY4, a type II transmembrane protein with a Trichome Birefringence-Like domain and a domain of unknown function (DUF231). Loss of AXY4 transcript results in a complete lack of O-acetyl substituents on xyloglucan in several tissues, except seeds. Seed xyloglucan is instead O-acetylated by the paralog AXY4like, as demonstrated by the analysis of the corresponding T-DNA insertional lines. Wall fractionation analysis of axy4 knockout mutants indicated that only a fraction containing xyloglucan is non-O-acetylated. Hence, AXY4/AXY4L is required for the O-acetylation of xyloglucan, and we propose that these proteins represent xyloglucan-specific O-acetyltransferases, although their donor and acceptor substrates have yet to be identified. An Arabidopsis ecotype, Ty-0, has reduced xyloglucan O-acetylation due to mutations in AXY4, demonstrating that O-acetylation of xyloglucan does not impact the plant’s fitness in its natural environment. The relationship of AXY4 with another previously identified group of Arabidopsis proteins involved in general wall O-acetylation, reduced wall acetylation, is discussed. PMID:22086088
The multi-axis vibration environment and man.

PubMed

Lovesey, E J

1970-12-01

Many investigations into the effects of vibration on man have been performed since Mallock's first study of London Underground vibrations in 1902. The vibration research has tended to be confined to the vertical (heave) axis, yet recent experiments have indicated that low frequency vibration along the lateral (sway) axis has a greater adverse effect upon comfort and performance. Measurements of the vibration environments in current forms of transport including motor vehicles, hovercraft and aircraft etc have shown that appreciable quantities of vibration along all three axes exist. Further vibration research should consider the effects of multi-axis vibrations upon man rather than limit tests to single axis vibration.
8. VIEW LOOKING NORTHWEST DOWN CENTRAL AXIS OF ROOM 110. ...

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

8. VIEW LOOKING NORTHWEST DOWN CENTRAL AXIS OF ROOM 110. NOTE CHANGE IN CEILING TREATMENT: WOOD PLANKS IN CENTER, ALL OTHER AREAS ARE GYPSUM BOARD. FLOOR IN CENTRAL AREA IS CONCRETE. POSTS AND BEAMS ARE ALL WOOD CONSTRUCTION. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA
Divergences between clinical and research methods for assessing personality disorders: implications for research and the evolution of axis II.

PubMed

Westen, D

1997-07-01

The purpose of this study was to examine the extent to which instruments for assessing axis II diverge from clinical diagnostic processes. Subjects in the first study were 52 clinicians with experience in assessment and treatment of patients with personality disorders, who were surveyed about the methods they use in clinical practice to make diagnoses and other aspects of the diagnostic process. A second study replicated the major findings with a random national sample of 1,901 experienced psychiatrists and psychologists. Whereas current instruments rely primarily on direct questions derived from DSM-IV, clinicians of every theoretical persuasion found direct questions useful for assessing axis I disorders but only marginally so for axis II. They made axis II diagnoses, instead, by listening to patients describe interpersonal interactions and observing their behavior with the interviewer. In contrast to findings with current research instruments, most patients with personality disorders in clinical practice receive only one axis II diagnosis, and if they receive more than one, one is considered primary. Clinicians reported treating a substantial number of patients for enduring personality patterns that current axis II instruments do not assess, many of which meet neither axis I nor axis II criteria, notably problems with relatedness, work, self-esteem, and chronic subclinical depressive traits. Measurements of axis II were constructed by using a model derived from axis I instruments that diverges from clinical diagnostic procedures in a way that may be problematic for the assessment of personality disorders and the development of a more clinically and empirically sound taxonomy.
Early-onset Major Depressive Disorder in men is associated with childlessness.

PubMed

Yates, William R; Meller, William H; Lund, Brian C; Thurber, Steve; Grambsch, Patricia L

2010-07-01

The self-reported number of children was compared for men and women from the National Epidemiologic Survey of Alcoholism and Related Conditions Survey (NESARC). Subjects with a diagnosis of major depressive disorder or bipolar disorder were compared to those without an axis I disorder. The effect of age, gender, marriage and diagnostic status on number of children was completed using multivariate analyses. Men with a history of major depressive disorder but not bipolar disorder reported higher rates of childlessness and lower mean number of children. This reduced number of children was related to an early age of onset of MDD. Thirty percent of men with an age of onset of MDD before 22 were childless compared to only 18.9% of men without an axis I disorder (Odds ratio=1.82, 95% CI=1.45-2.27). No effect of mood disorder on number of children was found in women with major depression or bipolar disorder. This study suggests that an early age of onset of major depressive disorder contributes to childlessness in men.
14 CFR 21.97 - Approval of major changes in type design.

Code of Federal Regulations, 2012 CFR

2012-01-01

... must— (1) Provide substantiating data and necessary descriptive data for inclusion in the type design... is made unless the applicant identifies in the necessary descriptive data for inclusion in the type... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Approval of major changes in type design...
Novel semi-automated kidney volume measurements in autosomal dominant polycystic kidney disease.

PubMed

Muto, Satoru; Kawano, Haruna; Isotani, Shuji; Ide, Hisamitsu; Horie, Shigeo

2018-06-01

We assessed the effectiveness and convenience of a novel semi-automatic kidney volume (KV) measuring high-speed 3D-image analysis system SYNAPSE VINCENT ® (Fuji Medical Systems, Tokyo, Japan) for autosomal dominant polycystic kidney disease (ADPKD) patients. We developed a novel semi-automated KV measurement software for patients with ADPKD to be included in the imaging analysis software SYNAPSE VINCENT ® . The software extracts renal regions using image recognition software and measures KV (VINCENT KV). The algorithm was designed to work with the manual designation of a long axis of a kidney including cysts. After using the software to assess the predictive accuracy of the VINCENT method, we performed an external validation study and compared accurate KV and ellipsoid KV based on geometric modeling by linear regression analysis and Bland-Altman analysis. Median eGFR was 46.9 ml/min/1.73 m 2 . Median accurate KV, Vincent KV and ellipsoid KV were 627.7, 619.4 ml (IQR 431.5-947.0) and 694.0 ml (IQR 488.1-1107.4), respectively. Compared with ellipsoid KV (r = 0.9504), Vincent KV correlated strongly with accurate KV (r = 0.9968), without systematic underestimation or overestimation (ellipsoid KV; 14.2 ± 22.0%, Vincent KV; - 0.6 ± 6.0%). There were no significant slice thickness-specific differences (p = 0.2980). The VINCENT method is an accurate and convenient semi-automatic method to measure KV in patients with ADPKD compared with the conventional ellipsoid method.

On the contact interaction of two identical stringers with an elastic semi-infinite continuous or vertically cracked plate

NASA Astrophysics Data System (ADS)

Grigoryan, M. S.

2018-04-01

This paper considers two connected contact problems on the interaction of stringers with an elastic semi-infinite plate. In the first problem, an elastic half-infinite continuous plate is reinforced on its boundary by two identical stringers exposed to a tensile external force. In the second problem, in the presence of the same stringers, the plate contains a collinear system of cracks on its vertical axis. The solution of both problems is reduced to the solution of singular integral equations (SIE) that are solved by a known numerical-analytical method.
Tailoring of EIA-649-1: Definition of Major (Class I) Engineering Change Proposal

DTIC Science & Technology

2015-05-15

MISSILE SYSTEMS CENTER TAILORING TAILORING OF EIA -649-1: DEFINITION OF MAJOR (CLASS I) ENGINEERING CHANGE PROPOSAL APPROVED FOR...PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED 1 Tailoring of EIA -649-1: Definition of Major (Class I) ECP. 1. Intent of this Tailoring Document...This tailoring document remedies a requirements gap in the industry consensus standard, EIA -649-1: 2015. Specifically, this tailoring provides a
Pilot study evaluating the effects of a cervical headgear on the C-axis: the growth axis of the dentomaxillary complex.

PubMed

Braun, Stanley; Bottrel, J Alexandre

2004-12-01

The C-axis, a growth vector for the dentomaxillary complex, is a means of quantifying complex maxillary growth in the sagittal plane through 3 key cephalometric measurements. This pilot study examined the effect of a cervical headgear, worn 8 to 10 hours per day, on the growth axis. The mean velocity of C-axis length increase in normally growing boys in the age range studied is 1.14 mm per year. In normally growing girls, the C-axis length increase is nonlinear, varying from a mean of 1.67 mm per year at age 9 and to 0.78 mm per year at 13.5 years of age. The cervical headgear reduced the C-axis length increases by 73.7% in boys and 61.1% in girls. The growth axis vector angle theta; was not clinically affected in either sex, but the palatal plane angle alpha became more acute in both sexes, rather than becoming more obtuse as it does in normally growing adolescents. Additional research should be undertaken to determine the effects on the C-axis by other cervical headgears having different lines of action relative to the center of resistance of the dentomaxillary complex, as well as occipital-pull and straight distal-pull headgear.
X-ray diffraction study of nanocrystalline and amorphous structure within major and minor ampullate dragline spider silks

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

Sampath, Sujatha; Isdebski, Thomas; Jenkins, Janelle E.

Synchrotron X-ray micro-diffraction experiments were carried out on Nephila clavipes (NC) and Argiope aurantia (AA) major (MA) and minor ampullate (MiA) fibers that make up dragline spider silk. The diffraction patterns show a semi-crystalline structure with {beta}-poly(L-alanine) nanocrystallites embedded in a partially oriented amorphous matrix. A superlattice reflection 'S' diffraction ring is observed, which corresponds to a crystalline component larger in size and is poorly oriented, when compared to the {beta}-poly(L-alanine) nanocrystallites that are commonly observed in dragline spider silks. Crystallite size, crystallinity and orientation about the fiber axis have been determined from the wide-angle X-ray diffraction (WAXD) patterns. Inmore » both NC and AA, the MiA silks are found to be more highly crystalline, when compared with the corresponding MA silks. Detailed analysis on the amorphous matrix shows considerable differences in the degree of order of the oriented amorphous component between the different silks studied and may play a crucial role in determining the mechanical properties of the silks.« less
University Chemistry Students' Learning Approaches and Willingness to Change Major

ERIC Educational Resources Information Center

Lastusaari, Mika; Murtonen, Mari

2013-01-01

A questionnaire with 22 Likert type items was developed to collect cross-sectional data from university chemistry students of different study years (N = 118). The aim was to obtain information on their learning approaches as well as their study preferences. Students willing to change from their major subject to medical education represented a…
Planning Major Curricular Change.

ERIC Educational Resources Information Center

Kirkland, Travis P.

Decision-making and change models can take many forms. One researcher (Nordvall, 1982) has suggested five conceptual models for introducing change: a political model; a rational decision-making model; a social interaction decision model; the problem-solving method; and an adaptive/linkage model which is an amalgam of each of the other models.…
Averaging scheme for atomic resolution off-axis electron holograms.

PubMed

Niermann, T; Lehmann, M

2014-08-01

All micrographs are limited by shot-noise, which is intrinsic to the detection process of electrons. For beam insensitive specimen this limitation can in principle easily be circumvented by prolonged exposure times. However, in the high-resolution regime several instrumental instabilities limit the applicable exposure time. Particularly in the case of off-axis holography the holograms are highly sensitive to the position and voltage of the electron-optical biprism. We present a novel reconstruction algorithm to average series of off-axis holograms while compensating for specimen drift, biprism drift, drift of biprism voltage, and drift of defocus, which all might cause problematic changes from exposure to exposure. We show an application of the algorithm utilizing also the possibilities of double biprism holography, which results in a high quality exit-wave reconstruction with 75 pm resolution at a very high signal-to-noise ratio. Copyright © 2014 Elsevier Ltd. All rights reserved.
Relationship between preoperative axis of astigmatism and postoperative astigmatic change after superior scleral incision phacoemulsification.

PubMed

Lyhne, N; Hansen, T E; Corydon, L

1998-07-01

To evaluate the effect of the preoperative axis of astigmatism on the outcome of corneal astigmatism after sutured 5.2 to 5.7 mm superior incision phacoemulsification. Departments of Opthalmology, Odense and Vejle Hospitals, Denmark. Seventy-three consecutive patients with preoperative corneal astigmatism of 2.0 diopters (D) or less, axial length between 20.0 and 25.5 mm, and no eye disease except cataract were grouped according to preoperative with-the-rule (WTR) or against-the-rule (ATR) astigmatism. The keratometric cylinder, induced keratometric cylinder (subtraction), and induced cylinder (Jaffe) were measured and calculated 10 to 12 months postoperatively. The postoperative keratometric cylinder and induced keratometric cylinder were significantly higher in the ATR group (P < .00001; mean difference [95% confidence limits]: 0.76 D [0.54; 0.98] and 0.69 D [0.46; 0.92], respectively). There was no significant difference between groups in induced cylinder (Jaffe). The estimated differences were significantly in favor of patients with preoperative WTR astigmatism. The findings support using temporal incision in cases with a preoperative ATR axis of astigmatism.
Binocular optical axis parallelism detection precision analysis based on Monte Carlo method

NASA Astrophysics Data System (ADS)

Ying, Jiaju; Liu, Bingqi

2018-02-01

According to the working principle of the binocular photoelectric instrument optical axis parallelism digital calibration instrument, and in view of all components of the instrument, the various factors affect the system precision is analyzed, and then precision analysis model is established. Based on the error distribution, Monte Carlo method is used to analyze the relationship between the comprehensive error and the change of the center coordinate of the circle target image. The method can further guide the error distribution, optimize control the factors which have greater influence on the comprehensive error, and improve the measurement accuracy of the optical axis parallelism digital calibration instrument.
Topical Review: Development of overgrown semi-polar GaN for high efficiency green/yellow emission

NASA Astrophysics Data System (ADS)

Wang, T.

2016-09-01

The most successful example of large lattice-mismatched epitaxial growth of semiconductors is the growth of III-nitrides on sapphire, leading to the award of the Nobel Prize in 2014 and great success in developing InGaN-based blue emitters. However, the majority of achievements in the field of III-nitride optoelectronics are mainly limited to polar GaN grown on c-plane (0001) sapphire. This polar orientation poses a number of fundamental issues, such as reduced quantum efficiency, efficiency droop, green and yellow gap in wavelength coverage, etc. To date, it is still a great challenge to develop longer wavelength devices such as green and yellow emitters. One clear way forward would be to grow III-nitride device structures along a semi-/non-polar direction, in particular, a semi-polar orientation, which potentially leads to both enhanced indium incorporation into GaN and reduced quantum confined Stark effects. This review presents recent progress on developing semi-polar GaN overgrowth technologies on sapphire or Si substrates, the two kinds of major substrates which are cost-effective and thus industry-compatible, and also demonstrates the latest achievements on electrically injected InGaN emitters with long emission wavelengths up to and including amber on overgrown semi-polar GaN. Finally, this review presents a summary and outlook on further developments for semi-polar GaN based optoelectronics.
Rivers through time: historical changes in the riparian vegetation of the semi-arid, winter rainfall region of South Africa in response to climate and land use.

PubMed

Hoffman, M Timm; Rohde, Richard Frederick

2011-01-01

This paper examines how the riparian vegetation of perennial and ephemeral rivers systems in the semi-arid, winter rainfall region of South Africa has changed over time. Using an environmental history approach we assess the extent of change in plant cover at 32 sites using repeat photographs that cover a time span of 36-113 years. The results indicate that in the majority of sites there has been a significant increase in cover of riparian vegetation in both the channel beds and adjacent floodplain environments. The most important species to have increased in cover across the region is Acacia karroo. We interpret the findings in the context of historical changes in climate and land use practices. Damage to riparian vegetation caused by mega-herbivores probably ceased sometime during the early 19th century as did scouring events related to large floods that occurred at regular intervals from the 15th to early 20th centuries. Extensive cutting of riparian vegetation for charcoal and firewood has also declined over the last 150 years. Changes in the grazing history as well as increased abstraction and dam building along perennial rivers in the region also account for some of the changes observed in riparian vegetation during the second half of the 20th century. Predictions of climate change related to global warming anticipate increased drought events with the subsequent loss of species and habitats in the study area. The evidence presented here suggests that an awareness of the region's historical ecology should be considered more carefully in the modelling and formulation of future climate change predictions as well as in the understanding of climate change impacts over time frames of decades and centuries.
Enclosed, off-axis solar concentrator

DOEpatents

Benitez, Pablo; Grip, Robert E; Minano, Juan C; Narayanan, Authi A; Plesniak, Adam; Schwartz, Joel A

2013-11-26

A solar concentrator including a housing having receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.
Major depressive disorder and suicidality in early HIV infection and its association with risk factors and negative outcomes as seen in semi-urban and rural Uganda.

PubMed

Kinyanda, Eugene; Nakasujja, Noeline; Levin, Jonathan; Birabwa, Harriet; Mpango, Richard; Grosskurth, Heiner; Seedat, Soraya; Patel, Vikram

2017-04-01

There is a paucity of research into the psychiatric problems associated with early stage HIV clinical disease in sub-Saharan Africa. A cross sectional study was undertaken among 899 adult ART naïve persons in early stage HIV clinical disease (participants with CD4≥250 and who were at WHO clinical Stage I or II) attending a semi-urban and a rural clinic in Uganda. The prevalence of major depressive disorder in this study was 14.0% [95% CI 11.7-6.3%] while that of 'moderate to high risk for suicidality' was 2.8% [95% CI 1.7%; 3.9%]. Multivariable analyses found that factors in the socio-demographic, vulnerability/protective and stress (only for major depressive disorder) domains were significantly associated with both major depressive disorder and 'moderate to high risk for suicidality'. Major depressive disorder but not 'moderate to high risk for suicidality' was significantly associated with impaired psychosocial functioning, greater utilisation of health services and non-adherence to septrin/dasone. Neither major depressive disorder nor 'moderate to high risk for suicidality' was associated with CD4 counts, risky sexual behaviour nor with non-utilisation of condoms. The bidirectional nature of some of the relationships between the investigated psychiatric problems, risk factors and outcomes in this cross sectional study makes it difficult to elucidate the actual direction of causality. Early stage HIV clinical disease is associated with considerable major depressive disorder and 'moderate to high risk for suicidality'. Therefore there is a need to integrate mental health into HIV interventions that target early stage HIV disease. Copyright © 2017 Elsevier B.V. All rights reserved.
Reduction of the coupling vibration between the bending vibrators of the frequency-change-type two-axis acceleration sensor

NASA Astrophysics Data System (ADS)

Sugawara, Sumio; Sasaki, Yoshifumi; Kudo, Subaru

2018-07-01

The frequency-change-type two-axis acceleration sensor uses a cross-type vibrator consisting of four bending vibrators. When coupling vibration exists between these four bending vibrators, the resonance frequency of each vibrator cannot be adjusted independently. In this study, methods of reducing the coupling vibration were investigated by finite-element analysis. A method of adjusting the length of the short arm of each vibrator was proposed for reducing the vibration. When piezoelectric ceramics were bonded to the single-sided surface of the vibrator, the method was not sufficient. Thus, the ceramics with the same dimensions were bonded to double-sided surfaces. As a result, a marked reduction was obtained in this case. Also, the linearity of the sensor characteristics was significantly improved in a small acceleration range. Accordingly, it was clarified that considering the symmetry along the thickness direction of the vibrator is very important.
Suicidal behavior on Axis VI: clinical data supporting a sixth Axis for DSM-V.

PubMed

Van Orden, Kimberly A; Witte, Tracy K; Holm-Denoma, Jill; Gordon, Kathryn H; Joiner, Thomas E

2011-01-01

Oquendo and colleagues (Oquendo, Baca-García, Mann, & Giner, 2008; Oquendo & Currier, 2009) recommend that DSM-V emphasize suicide risk assessment on a sixth axis, thereby increasing regularity of suicide risk assessments. We propose that evidence of nonredundancy with Axis V - Global Assessment of Functioning (GAF) is one piece of data that can serve as a starting point for a line of research establishing incremental predictive utility for a separate suicide risk assessment in the DSM framework. A standardized suicide risk assessment protocol, measures of depressive, anxious, and eating disordered symptomatology, as well as an index of comorbidity were administered to a sample of 412 adult outpatients. Our data indicate that data from standardized suicide risk assessments are associated with indices of symptomatology severity as well as comorbidity, controlling for GAF. These results support the nonredundancy of the assessments and suggest the utility of longitudinal investigations of the predictive utility of a sixth DSM axis in the assessment of suicide risk.
An economical semi-analytical orbit theory for micro-computer applications

NASA Technical Reports Server (NTRS)

Gordon, R. A.

1988-01-01

An economical algorithm is presented for predicting the position of a satellite perturbed by drag and zonal harmonics J sub 2 through J sub 4. Simplicity being of the essence, drag is modeled as a secular decay rate in the semi-axis (retarded motion); with the zonal perturbations modeled from a modified version of the Brouwers formulas. The algorithm is developed as: an alternative on-board orbit predictor; a back up propagator requiring low energy consumption; or a ground based propagator for microcomputer applications (e.g., at the foot of an antenna). An O(J sub 2) secular retarded state partial matrix (matrizant) is also given to employ with state estimation. The theory was implemented in BASIC on an inexpensive microcomputer, the program occupying under 8K bytes of memory. Simulated trajectory data and real tracking data are employed to illustrate the theory's ability to accurately accommodate oblateness and drag effects.
Direction of spin axis and spin rate of the pitched baseball.

PubMed

Jinji, Tsutomu; Sakurai, Shinji

2006-07-01

In this study, we aimed to determine the direction of the spin axis and the spin rate of pitched baseballs and to estimate the associated aerodynamic forces. In addition, the effects of the spin axis direction and spin rate on the trajectory of a pitched baseball were evaluated. The trajectories of baseballs pitched by both a pitcher and a pitching machine were recorded using four synchronized video cameras (60 Hz) and were analyzed using direct linear transform (DLT) procedures. A polynomial function using the least squares method was used to derive the time-displacement relationship of the ball coordinates during flight for each pitch. The baseball was filmed immediately after ball release using a high-speed video camera (250 Hz), and the direction of the spin axis and the spin rate (omega) were calculated based on the positional changes of the marks on the ball. The lift coefficient was correlated closely with omegasinalpha (r = 0.860), where alpha is the angle between the spin axis and the pitching direction. The term omegasinalpha represents the vertical component of the velocity vector. The lift force, which is a result of the Magnus effect occurring because of the rotation of the ball, acts perpendicularly to the axis of rotation. The Magnus effect was found to be greatest when the angular and translational velocity vectors were perpendicular to each other, and the break of the pitched baseball became smaller as the angle between these vectors approached 0 degrees. Balls delivered from a pitching machine broke more than actual pitcher's balls. It is necessary to consider the differences when we use pitching machines in batting practice.
Thyroid hormone receptor beta2 is strongly up-regulated at all levels of the hypothalamo-pituitary-thyroidal axis during late embryogenesis in chicken.

PubMed

Grommen, Sylvia V H; Arckens, Lutgarde; Theuwissen, Tim; Darras, Veerle M; De Groef, Bert

2008-03-01

In this study, we tried to elucidate the changes in thyroid hormone (TH) receptor beta2 (TRbeta2) expression at the different levels of the hypothalamo-pituitary-thyroidal (HPT) axis during the last week of chicken embryonic development and hatching, a period characterized by an augmented activity of the HPT axis. We quantified TRbeta2 mRNA in retina, pineal gland, and the major control levels of the HPT axis - brain, pituitary, and thyroid gland - at day 18 of incubation, and found the most abundant mRNA content in retina and pituitary. Thyroidal TRbeta2 mRNA content increased dramatically between embryonic day 14 and 1 day post-hatch. In pituitary and hypothalamus, TRbeta2 mRNA expression rose gradually, in parallel with increases in plasma thyroxine concentrations. Using in situ hybridization, we have demonstrated the presence of TRbeta2 mRNA throughout the diencephalon and confirmed the elevation in TRbeta2 mRNA expression in the hypophyseal thyrotropes. In vitro incubation with THs caused a down-regulation of TRbeta2 mRNA levels in embryonic but not in post-hatch pituitaries. The observed expression patterns in pituitary and diencephalon may point to substantial changes in TRbeta2-mediated TH feedback active during the perinatal period. The strong rise in thyroidal TRbeta2 mRNA content could be indicative of an augmented modulation of thyroid development and/or function by THs toward and after hatching. Finally, THs proved to exert an age-dependent effect on pituitary TRbeta2 mRNA expression.
Development of a dual-axis hybrid-type tactile sensor using PET film

NASA Astrophysics Data System (ADS)

Seonggi, Kim; Koo, Ja Choon; Choi, Hyouk Ryeol; Moon, Hyungpil

2013-04-01

In previous work, a dual-axis hybrid-type tactile sensor using PDMS (Polydimethylsiloxane) with a pair of metal electrodes, (which were deposited directly on the PDMS surface), was proposed. The hybrid sensor can measure the normal force and the shear force from the measurement of the change of capacitance and resistance values from the one pair of electrodes. However, the metal is hard to be deposited on the surface of the PDMS because the PDMS is hydrophobic. The hydrophobic surface can be changed to hydrophilic using O2 Plasma treatment or UV treatment. When O2 plasma treatment or UV treatment is used, there is the problem that the processing of the metal deposition and the wiring completed in a very short period of limited time. Also, the deposited metal on the surface of the PDMS is easy to break because the deposited metal is exposed in the air. In this paper, we propose a dual-axis hybrid-type tactile sensor where the PET (polyethylene terephthalate) film is inserted between the PDMS films. The deposited metal is not removed easily from the PET film because the adhesion is strong. Also, the PDMS surrounding the PET film plays the roles of dielectric elastomer and shielding the deposited metal from the external environment at same time. Experimental results verify the effectiveness of the fabricated dual-axis hybrid-type force sensor.
Past orientation of the lunar spin axis.

PubMed

Ward, W R

1975-08-01

The orientation of the lunar spin axis is traced from the early history of the earth-moon system to the present day. Tides raised on the earth by the moon have caused an expansion of the lunar orbit. Tides raised on the moon by the earth have de-spun the moon to synchronous rotation and driven its spin axis to a Cassini state-that is, in a coprecessing configuration, coplanar with the lunar orbit normal and the normal to the Laplacian plane (which is at present coincident with the normal to the ecliptic). This combination of events has resulted in a complex history for the lunar spin axis. For much of the period during which its orbital semimajor axis expanded between 30 and 40 earth radii, the obliquity of the moon was of order 25 degrees to 50 degrees . In fact, for a brief period the obliquity periodically attained a value as high as 77 degrees ; that is, the spin axis of the moon was only 13 degrees from lying in its orbit plane.

Past orientation of the lunar spin axis

NASA Technical Reports Server (NTRS)

Ward, W. R.

1975-01-01

The orientation of the lunar spin axis is traced from the early history of the earth-moon system to the present day. Tides raised on the earth by the moon have caused an expansion of the lunar orbit. Tides raised on the moon by the earth have de-spun the moon to synchronous rotation and driven its spin axis to a Cassini state - that is, in a coprecessing configuration, coplanar with the lunar orbit normal and the normal to the Laplacian plane (which is at present coincident with the normal to the ecliptic). This combination of events has resulted in a complex history for the lunar spin axis. For much of the period during which its orbital semimajor axis expanded between 30 and 40 earth radii, the obliquity of the moon was of order 25 to 50 deg. In fact, for a brief period the obliquity periodically attained a value as high as 77 deg; that is, the spin axis of the moon was only 13 deg from lying in its orbit plane.
ESTIMATING TRANSPORT AND DEPOSITION OF A SEMI-VOLATILE COMPOUND WITH A REGIONAL PHOTOCHEMICAL MODEL

EPA Science Inventory

To simulate the fate of compounds that are considered semi-volatile and toxic, we have modified a model for regional particulate matter. Our changes introduce a semi-volatile compound into the atmosphere as gaseous emissions from an area source. Once emitted, the gas can transf...
A New Axi-Symmetric Element for Thin Walled Structures

NASA Astrophysics Data System (ADS)

Cardoso, Rui P. R.; Yoon, Jeong Whan; Dick, Robert E.

2010-06-01

A new axi-symmetric finite element for sheet metal forming applications is presented in this work. It uses the solid-shell element's concept with only a single element layer and multiple integration points along the thickness direction. The cross section of the element is composed of four nodes with two degrees of freedom each. The proposed formulation overcomes major locking pathologies including transverse shear locking, Poisson's locking and volumetric locking. Some examples are shown to demonstrate the performance and accuracy of the proposed element with special focus on the numerical simulations for the beverage can industry.
Improved semi-supervised online boosting for object tracking

NASA Astrophysics Data System (ADS)

Li, Yicui; Qi, Lin; Tan, Shukun

2016-10-01

The advantage of an online semi-supervised boosting method which takes object tracking problem as a classification problem, is training a binary classifier from labeled and unlabeled examples. Appropriate object features are selected based on real time changes in the object. However, the online semi-supervised boosting method faces one key problem: The traditional self-training using the classification results to update the classifier itself, often leads to drifting or tracking failure, due to the accumulated error during each update of the tracker. To overcome the disadvantages of semi-supervised online boosting based on object tracking methods, the contribution of this paper is an improved online semi-supervised boosting method, in which the learning process is guided by positive (P) and negative (N) constraints, termed P-N constraints, which restrict the labeling of the unlabeled samples. First, we train the classification by an online semi-supervised boosting. Then, this classification is used to process the next frame. Finally, the classification is analyzed by the P-N constraints, which are used to verify if the labels of unlabeled data assigned by the classifier are in line with the assumptions made about positive and negative samples. The proposed algorithm can effectively improve the discriminative ability of the classifier and significantly alleviate the drifting problem in tracking applications. In the experiments, we demonstrate real-time tracking of our tracker on several challenging test sequences where our tracker outperforms other related on-line tracking methods and achieves promising tracking performance.
Parabrachial nucleus neuronal responses to off-vertical axis rotation in macaques

PubMed Central

McCandless, Cyrus H.; Balaban, Carey D.

2010-01-01

The caudal aspect of the parabrachial nucleus (PBN) contains neurons responsive to whole body, periodic rotational stimulation in alert monkeys. This study characterizes the angular and linear motion-sensitive response properties of PBN unit responses during off-vertical axis rotation (OVAR) and position trapezoid stimulation. The OVAR responses displayed a constant firing component which varied from the firing rate at rest. Nearly two-thirds of the units also modulated their discharges with respect to head orientation (re: gravity) during constant velocity OVAR stimulation. The modulated response magnitudes were equal during ipsilateral and contralateral OVARs, indicative of a one-dimensional accelerometer. These response orientations during OVAR divided the units into three spatially tuned populations, with peak modulation responses centered in the ipsilateral ear down, contralateral anterior semicircular canal down, and occiput down orientations. Because the orientation of the OVAR modulation response was opposite in polarity to the orientation of the static tilt component of responses to position trapezoids for the majority of units, the linear acceleration responses were divided into colinear dynamic linear and static tilt components. The orientations of these unit responses formed two distinct population response axes: (1) units with an interaural linear response axis and (2) units with an ipsilateral anterior semicircular canal-contralateral posterior semicircular canal plane linear response axis. The angular rotation sensitivity of these units is in a head-vertical plane that either contains the linear acceleration response axis or is perpendicular to the linear acceleration axis. Hence, these units behave like head-based (‘strap-down’) inertial guidance sensors. Because the PBN contributes to sensory and interoceptive processing, it is suggested that vestibulo-recipient caudal PBN units may detect potentially dangerous anomalies in control of postural
Orbital Evolution and Physical Characteristics of Object "Peggy" at the Edge of Saturn's A Ring

NASA Astrophysics Data System (ADS)

Murray, C.; Cooper, N. J.; Noyelles, B.; Renner, S.; Araujo, N.

2016-12-01

Images taken with the Cassini ISS instrument on 2013 April 15 showed the presence of a bright, extended object at the edge of Saturn's A ring. The gravitational signature of the object often appears as a discontinuity in the azimuthal profile of the ring edge and a subsequent analysis revealed that the object (nicknamed "Peggy") was detectable in ISS images as far back as 2012. The morphology of the signature is a function of the orbital phase suggesting that the object has a relative eccentricity or periapse with respect to the surrounding ring material. Tracking the signature allows a determination of the object's semi-major axis and following the initial detection this has varied by as much as 5 km. At no stage has the object been as bright as it was at the time of its discovery, suggesting that a collisional event had recently occurred. Here we report on the latest Cassini ISS observations of "Peggy" and their interpretation. These will include the calculated changes in its semi-major axis since 2013, constraints on its mass based on numerical integrations of its perturbing effect on adjacent ring particles, and what has been learned from a recent 8 h sequence of high resolution ISS images specially designed to track "Peggy" for more than half an orbital period.
Deep cytoplasmic rearrangements in axis-respecified Xenopus embryos

NASA Technical Reports Server (NTRS)

Denegre, J. M.; Danilchik, M. V.

1993-01-01

In fertilized eggs of the frog Xenopus, the vegetal yolk mass rotates away from the future dorsal side (J. P. Vincent and J. Gerhart, 1987, Dev. Biol. 123, 526-539), and a major rearrangement of the deep animal hemisphere cytoplasm produces a characteristic swirl in the prospective dorsal side (M. V. Danilchik and J. M. Denegre, 1991, Development 111, 845-856). The relationship between this swirl and determination of the dorsal-ventral axis was further investigated by attempting to experimentally separate the positions of the swirl and the dorsal-ventral axis. Eggs were obliquely oriented in the gravity field to respecify the direction of yolk mass rotation and the position of the dorsal-ventral axis. When yolk mass rotation occurred in the absence of a sperm, as in activated eggs, a swirl pattern formed on the side away from which the yolk mass had rotated. In fertilized eggs tipped with the sperm entry point (SEP) down or to the side, swirl patterns were always found to form on the side away from which the yolk mass was displaced. However, in eggs tipped SEP up, in which the yolk mass was forced to rotate away from the SEP, more complicated rearrangements were observed in addition to the rotation-oriented swirl. Because the direction of yolk mass rotation was found to be influenced by both gravity and the actual position of the SEP in obliquely oriented eggs (SEP to the side), such complicated rearrangement patterns may result from opposing forces generated by both yolk mass rotation and the expanding sperm aster. Thus, except in cases in which the influences of SEP position and unit gravity opposed each other, it was not possible to experimentally separate the position of the deep cytoplasmic swirl from the direction of yolk mass rotation, and therefore the position of the prospective dorsal side.
Endocannabinoid Signaling and the Hypothalamic-Pituitary-Adrenal Axis.

PubMed

Hillard, Cecilia J; Beatka, Margaret; Sarvaideo, Jenna

2016-12-06

The elucidation of Δ9-tetrahydrocannabinol as the active principal of Cannabis sativa in 1963 initiated a fruitful half-century of scientific discovery, culminating in the identification of the endocannabinoid signaling system, a previously unknown neuromodulatory system. A primary function of the endocannabinoid signaling system is to maintain or recover homeostasis following psychological and physiological threats. We provide a brief introduction to the endocannabinoid signaling system and its role in synaptic plasticity. The majority of the article is devoted to a summary of current knowledge regarding the role of endocannabinoid signaling as both a regulator of endocrine responses to stress and as an effector of glucocorticoid and corticotrophin-releasing hormone signaling in the brain. We summarize data demonstrating that cannabinoid receptor 1 (CB1R) signaling can both inhibit and potentiate the activation of the hypothalamic-pituitary-adrenal axis by stress. We present a hypothesis that the inhibitory arm has high endocannabinoid tone and also serves to enhance recovery to baseline following stress, while the potentiating arm is not tonically active but can be activated by exogenous agonists. We discuss recent findings that corticotropin-releasing hormone in the amygdala enables hypothalamic-pituitary-adrenal axis activation via an increase in the catabolism of the endocannabinoid N-arachidonylethanolamine. We review data supporting the hypotheses that CB1R activation is required for many glucocorticoid effects, particularly feedback inhibition of hypothalamic-pituitary-adrenal axis activation, and that glucocorticoids mobilize the endocannabinoid 2-arachidonoylglycerol. These features of endocannabinoid signaling make it a tantalizing therapeutic target for treatment of stress-related disorders but to date, this promise is largely unrealized. © 2017 American Physiological Society. Compr Physiol 7:1-15, 2017. Copyright © 2017 John Wiley & Sons, Inc.
Design, Fabrication and Characterization of a MEMS-Based Three-Dimensional Electric Field Sensor with Low Cross-Axis Coupling Interference

PubMed Central

Ling, Biyun; Peng, Chunrong; Ren, Ren; Chu, Zhaozhi; Zhang, Zhouwei; Lei, Hucheng; Xia, Shanhong

2018-01-01

One of the major concerns in the development of three-dimensional (3D) electric field sensors (EFSs) is their susceptibility to cross-axis coupling interference. The output signal for each sensing axis of a 3D EFS is often coupled by electric field components from the two other orthogonal sensing axes. In this paper, a one-dimensional (1D) electric field sensor chip (EFSC) with low cross-axis coupling interference is presented. It is designed to be symmetrical, forming a pair of in-plane symmetrically-located sensing structures. Using a difference circuit, the 1D EFSC is capable of sensing parallel electric fields along symmetrical structures and eliminating cross-axis coupling interference, which is contrast to previously reported 1D EFSCs designed for perpendicular electric field component measurement. Thus, a 3D EFS with low cross-axis coupling interference can be realized using three proposed 1D EFSCs. This 3D EFS has the advantages of low cross-axis coupling interference, small size, and high integration. The testing and calibration systems of the proposed 3D EFS were developed. Experimental results show that in the range of 0–120 kV/m, cross-axis sensitivities are within 5.48%, and the total measurement errors of this 3D EFS are within 6.16%. PMID:29543744
μ-PIV measurements of the ensemble flow fields surrounding a migrating semi-infinite bubble.

PubMed

Yamaguchi, Eiichiro; Smith, Bradford J; Gaver, Donald P

2009-08-01

Microscale particle image velocimetry (μ-PIV) measurements of ensemble flow fields surrounding a steadily-migrating semi-infinite bubble through the novel adaptation of a computer controlled linear motor flow control system. The system was programmed to generate a square wave velocity input in order to produce accurate constant bubble propagation repeatedly and effectively through a fused glass capillary tube. We present a novel technique for re-positioning of the coordinate axis to the bubble tip frame of reference in each instantaneous field through the analysis of the sudden change of standard deviation of centerline velocity profiles across the bubble interface. Ensemble averages were then computed in this bubble tip frame of reference. Combined fluid systems of water/air, glycerol/air, and glycerol/Si-oil were used to investigate flows comparable to computational simulations described in Smith and Gaver (2008) and to past experimental observations of interfacial shape. Fluorescent particle images were also analyzed to measure the residual film thickness trailing behind the bubble. The flow fields and film thickness agree very well with the computational simulations as well as existing experimental and analytical results. Particle accumulation and migration associated with the flow patterns near the bubble tip after long experimental durations are discussed as potential sources of error in the experimental method.
Introducing a new semi-active engine mount using force controlled variable stiffness

NASA Astrophysics Data System (ADS)

Azadi, Mojtaba; Behzadipour, Saeed; Faulkner, Gary

2013-05-01

This work introduces a new concept in designing semi-active engine mounts. Engine mounts are under continuous development to provide better and more cost-effective engine vibration control. Passive engine mounts do not provide satisfactory solution. Available semi-active and active mounts provide better solutions but they are more complex and expensive. The variable stiffness engine mount (VSEM) is a semi-active engine mount with a simple ON-OFF control strategy. However, unlike available semi-active engine mounts that work based on damping change, the VSEM works based on the static stiffness change by using a new fast response force controlled variable spring. The VSEM is an improved version of the vibration mount introduced by the authors in their previous work. The results showed significant performance improvements over a passive rubber mount. The VSEM also provides better vibration control than a hydromount at idle speed. Low hysteresis and the ability to be modelled by a linear model in low-frequency are the advantages of the VSEM over the vibration isolator introduced earlier and available hydromounts. These specifications facilitate the use of VSEM in the automotive industry, however, further evaluation and developments are needed for this purpose.
Agricultural Management and Climatic Change Are the Major Drivers of Biodiversity Change in the UK

PubMed Central

Burns, Fiona; Eaton, Mark A.; Beckmann, Björn C.; Brereton, Tom; Brooks, David R.; Brown, Peter M. J.; Al Fulaij, Nida; Gent, Tony; Henderson, Ian; Noble, David G.; Parsons, Mark; Powney, Gary D.; Roy, Helen E.; Stroh, Peter; Walker, Kevin; Wilkinson, John W.; Wotton, Simon R.; Gregory, Richard D.

2016-01-01

Action to reduce anthropogenic impact on the environment and species within it will be most effective when targeted towards activities that have the greatest impact on biodiversity. To do this effectively we need to better understand the relative importance of different activities and how they drive changes in species’ populations. Here, we present a novel, flexible framework that reviews evidence for the relative importance of these drivers of change and uses it to explain recent alterations in species’ populations. We review drivers of change across four hundred species sampled from a broad range of taxonomic groups in the UK. We found that species’ population change (~1970–2012) has been most strongly impacted by intensive management of agricultural land and by climatic change. The impact of the former was primarily deleterious, whereas the impact of climatic change to date has been more mixed. Findings were similar across the three major taxonomic groups assessed (insects, vascular plants and vertebrates). In general, the way a habitat was managed had a greater impact than changes in its extent, which accords with the relatively small changes in the areas occupied by different habitats during our study period, compared to substantial changes in habitat management. Of the drivers classified as conservation measures, low-intensity management of agricultural land and habitat creation had the greatest impact. Our framework could be used to assess the relative importance of drivers at a range of scales to better inform our policy and management decisions. Furthermore, by scoring the quality of evidence, this framework helps us identify research gaps and needs. PMID:27007973
Dinotefuran-induced morphophysiological changes in the ovaries and midgut of semi-engorged females Rhipicephalus sanguineus Latreille, 1806 (Acari: Ixodidae) ticks.

PubMed

de Oliveira, Patrícia Rosa; Remédio, Rafael Neodini; Bechara, Gervásio Henrique; Anholeto, Luis Adriano; Mathias, Maria Izabel Camargo

2016-02-01

The present study demonstrated the effects of dinotefuran (active compound of the Protetor Pet® acaricide) in germ cells and the digestive processes of semi-engorged females of R. sanguineus exposed to different concentrations of the chemical. For this purpose, 120 semi-engorged females were divided into four treatment groups with 30 individuals each: group I or control (distilled water), group II (5000 ppm), group III (6250 ppm), and group IV (8334 ppm of dinotefuran). All ticks were immersed in different concentrations of dinotefuran or in distilled water for 5 min and then were dried and stored in biological oxygen demand (BOD) incubator for 7 days. The results show the action of this compound, exhibiting morphohistologic and histochemical changes in the oocytes and the midgut cells of individuals of different groups, which were compared with those of group I (control). The alterations occurred mainly in relation to the size of the germ cells and yolk granules; presence, quantity, size, and location of vacuoles found in the cytoplasm of these germ cells; the damage occurred in the generative cells of the midgut; the size of the digestive cells; the quantity of blood elements captured, accumulated digestive wastes and digestive vacuoles found in the cytoplasm of the digestive cells of the midgut, as well as the amount and distribution of proteins, polysaccharides, lipids of all cells in both organs. So, it has demonstrated the effectiveness of dinotefuran in the reduction of fertility and digestive processes of semi-engorged females of R. sanguineus, data that points the possibility of employing this chemical to control these ectoparasites.
The prevalence of resonances among large-a transneptunian objects

NASA Astrophysics Data System (ADS)

Gladman, Brett; Volk, Kathryn; Van Laerhoven, Christa

2018-04-01

The detached population consists of transneptunian objects (TNOs) with large semi-major axes and sufficiently high perihelia (roughly q>38 au, but there is no simple cut). However, what constitutes 'large semi-major axis' has been, and continues to be, unclear. Once beyond the apehlia of the classical Kuiper Belt (which extends out to about 60 au), objects with semimajor axes from a=60-150 au can be detached, but there are a reasonable number of objects in this range known to be in mean-motion resonances with Neptune. Beyond a=150 au, however, it is a widely-held belief that resonances become `unimportant', and that a q>38 au cut (or sometimes q>50 au) with a>150 au isolates a set of large semimajor axis detached objects. However, once semimajor axes become this large, the orbit determination of the object discovered near perihelion becomes a much harder task then for low-a TNOs. Because small velocity differences near the perihelion of large-a orbits cause large changes the fitted orbital in semimajor axis, extremely good and long baseline astrometry is required to reduce the semimajor axis uncertainty to be smaller than the few tenths of an astronomical unit widths of mean motion resonances. By carefully analyzing the astrometric data of all known large semimajor axis objects, we show that a very large fraction of the objects are in fact likely in high-order mean-motion resonances with Neptune. This prevealence for actually being resonant with Neptune would imply that hypothesized planets are problematic as they would remove the detached objects from these resonances. Instead, we favor a view in which the large-a population is the surviving remnant of a massive early scattering disk, whose surviving members are sculpted mostly by diffusive gravitational interactions with the four giant planets over the last four gigayears, but whose initial emplacement mechanism (in particular: perihelion lifting mechanism) is still unclear but of critical importance to the early
The explicit form of the rate function for semi-Markov processes and its contractions

NASA Astrophysics Data System (ADS)

Sughiyama, Yuki; Kobayashi, Testuya J.

2018-03-01

We derive the explicit form of the rate function for semi-Markov processes. Here, the ‘random time change trick’ plays an essential role. Also, by exploiting the contraction principle of large deviation theory to the explicit form, we show that the fluctuation theorem (Gallavotti-Cohen symmetry) holds for semi-Markov cases. Furthermore, we elucidate that our rate function is an extension of the level 2.5 rate function for Markov processes to semi-Markov cases.
Multi-party semi-quantum key distribution-convertible multi-party semi-quantum secret sharing

NASA Astrophysics Data System (ADS)

Yu, Kun-Fei; Gu, Jun; Hwang, Tzonelih; Gope, Prosanta

2017-08-01

This paper proposes a multi-party semi-quantum secret sharing (MSQSS) protocol which allows a quantum party (manager) to share a secret among several classical parties (agents) based on GHZ-like states. By utilizing the special properties of GHZ-like states, the proposed scheme can easily detect outside eavesdropping attacks and has the highest qubit efficiency among the existing MSQSS protocols. Then, we illustrate an efficient way to convert the proposed MSQSS protocol into a multi-party semi-quantum key distribution (MSQKD) protocol. The proposed approach is even useful to convert all the existing measure-resend type of semi-quantum secret sharing protocols into semi-quantum key distribution protocols.
Nitric oxide in the stress axis.

PubMed

López-Figueroa, M O; Day, H E; Akil, H; Watson, S J

1998-10-01

In recent years nitric oxide (NO) has emerged as a unique biological messenger. NO is a highly diffusible gas, synthesized from L-arginine by the enzyme nitric oxide synthase (NOS). Three unique subtypes of NOS have been described, each with a specific distribution profile in the brain and periphery. NOS subtype I is present, among other areas, in the hippocampus, hypothalamus, pituitary and adrenal gland. Together these structures form the limbic-hypothalamic-pituitary-adrenal (LHPA) or stress axis, activation of which is one of the defining features of a stress response. Evidence suggests that NO may modulate the release of the stress hormones ACTH and corticosterone, and NOS activity and transcription is increased in the LHPA axis following various stressful stimuli. Furthermore, following activation of the stress axis, glucocorticoids are thought to down-regulate the transcription and activity of NOS via a feedback mechanism. Taken together, current data indicate a role for NO in the regulation of the LHPA axis, although at present this role is not well defined. It has been suggested that NO may act as a cellular communicator in plasticity and development, to facilitate the activation or the release of other neurotransmitters, to mediate immune responses, and/or as a vasodilator in the regulation of blood flow. In the following review we summarize some of the latest insights into the function of NO, with special attention to its relationship with the LHPA axis.
The Impact of Maternal Childhood Abuse on Maternal and Infant HPA Axis Function in the Postpartum Period

PubMed Central

Brand, Sarah R.; Brennan, Patricia A.; Newport, D. Jeffrey; Smith, Alicia K.; Weiss, Tamara; Stowe, Zachary N.

2009-01-01

Summary Background Early life trauma, particularly child abuse, has been associated with aberrations in hypothalamic-pituitary-adrenal (HPA) axis functioning in adulthood. However, the relationship of early abuse and later adult neuroendocrine changes may be moderated by additional factors such as comorbid psychopathology and recent life stress. Parental exposure to child abuse may have transgenerational effects, with offspring of abuse victims showing similar neuroendocrine profiles as their mothers. The majority of previous studies in this area focus on adult offspring, and the degree to which the effects of parental child abuse can be detected earlier in the development of the offspring remains obscure. Methods The current study utilized a clinical sample of women with a history of MDD (N= 126), to examine the effects of maternal early life sexual and physical abuse (Childhood Trauma Questionnaire; CTQ) on both maternal and infant salivary cortisol levels during a laboratory stress paradigm at 6 months postpartum. Results Maternal child abuse was associated with steeper declines in cortisol in the mothers, and lower baseline cortisol in their infants. Comorbid maternal PTSD, current maternal depressive symptoms, and recent life stressors were significant moderators of maternal cortisol change. Maternal abuse history was associated with increases in cortisol levels in those mothers who experienced these additional stressors. Similarly, a history of early maternal abuse and comorbid PTSD was associated with greater increases in infant cortisol levels. Conclusions Maternal childhood abuse was associated with HPA axis function in both the mother and the infant during the postpartum period. PMID:19931984
SU-F-T-425: Head-Scatter Off-Axis for FFF Megavoltage Photon Beams

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

Zhu, T; Penjweini, R; Dimofte, A

Purpose: Head-scatter photons inside a clinical accelerator cause the output to change with collimator setting. On the central-axis, this contribution is well-described by output factor in air (or head-scatter factor). However, a few studies have examined this component at off-axis points. Methods: We define the head-scatter off-axis ratio, HOA, as the ratio of the water kerma in air due to head-scatter photons at the off-axis position x to the water kerma from direct primary photons on the central axis: HOA(cx,cy,xy) = (Q(cx,cy,x) – QP(cx,cy,x))/QP(cx,cy,0), where Q(cx, cy,x), QP(cx,cy,x) are charges measured by an ionization chamber in a miniphantom for collimatormore » setting cx × cy and cx × 3 cm, respectively, at off-axis point x. “Direct primary” is those photons that come from the source without interactions in the intervening structures. Results: We measured HOA for two energies (6XFFF and 6X) along X and Y jaw directions for various collimator settings. The shape of HOA has well defined penumbra for collimator setting larger than 10 × 10 cm2. Conclusion: The narrow gaussian component is interpreted as the source of photons scattered in the flattening filter and the primary collimator. The broad component is attributed to photons scattered in the secondary (variable) collimators. By a direct comparison between 6X and 6XFFF beams, we can confirm that the second component is indeed coming from collimator jaws and identify the parts coming from the primary collimator and the flattening filter, respectively.« less
20 CFR 418.1210 - What is not a major life-changing event?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false What is not a major life-changing event? 418.1210 Section 418.1210 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare Part B Income-Related Monthly Adjustment Amount Determinations Using A More Recent Tax Year's Modified...

Effect of disagreement between refractive, keratometric, and topographic determination of astigmatic axis on suture removal after penetrating keratoplasty

PubMed Central

Sarhan, A; Dua, H.; Beach, M.

2000-01-01

BACKGROUND/AIMS—Post-keratoplasty astigmatism can be managed by selective suture removal in the steep axis. Corneal topography, keratometry, and refraction are used to determine the steep axis for suture removal. However, often there is a disagreement between the topographically determined steep axis and sutures to be removed and that determined by keratometry and refraction. The purpose of this study was to evaluate any difference in the effect of suture removal, on visual acuity and astigmatism, in patients where such a disagreement existed. METHODS—37 cases (from 37 patients) of selective suture removal after penetrating keratoplasty, were included. In the first group "the disagreement group" (n=15) there was disagreement between corneal topography, keratometry, and refraction regarding the axis of astigmatism and sutures to be removed. In the second group "the agreement group" (n=22) there was agreement between corneal topography, keratometry, and refraction in the determination of the astigmatic axis and sutures to be removed. Sutures were removed according to the corneal topography, at least 5 months postoperatively. Vector analysis for change in astigmatism and visual acuity after suture removal was compared between groups. RESULTS—In the disagreement group, the amount of vector corrected change in refractive, keratometric, and topographic astigmatism after suture removal was 3.45 (SD 2.34), 3.57 (1.63), and 2.83 (1.68) dioptres, respectively. In the agreement group, the amount of vector corrected change in refractive, keratometric, and topographic astigmatism was 5.95 (3.52), 5.37 (3.29), and 4.71 (2.69) dioptres respectively. This difference in the vector corrected change in astigmatism between groups was statistically significant, p values of 0.02, 0.03, and 0.03 respectively. Visual acuity changes were more favourable in the agreement group. Improvement or no change in visual acuity occurred in 90.9% in the agreement group compared
Semi-continuous ultrasonic sounding and changes of ultrasonic signal characteristics as a sensitive tool for the evaluation of ongoing microstructural changes of experimental mortar bars tested for their ASR potential.

PubMed

Lokajíček, T; Kuchařová, A; Petružálek, M; Šachlová, Š; Svitek, T; Přikryl, R

2016-09-01

Semi-continuous ultrasonic sounding of experimental mortar bars used in the accelerated alkali silica reactivity laboratory test (ASTM C1260) is proposed as a supplementary measurement technique providing data that are highly sensitive to minor changes in the microstructure of hardening/deteriorating concrete mixture. A newly designed, patent pending, heating chamber was constructed allowing ultrasonic sounding of mortar bars, stored in accelerating solution without necessity to remove the test specimens from the bath during the measurement. Subsequent automatic data analysis of recorded ultrasonic signals proved their high correlation to the measured length changes (expansion) and their high sensitivity to microstructural changes. The changes of P-wave velocity, and of the energy, amplitude, and frequency of ultrasonic signal, were in the range of 10-80%, compared to 0.51% change of the length. Results presented in this study thus show that ultrasonic sounding seems to be more sensitive to microstructural changes due to ongoing deterioration of concrete microstructure by alkali-silica reaction than the dimensional changes. Copyright © 2016. Published by Elsevier B.V.
Do Students' College Major Choices Respond to Changes in Wages? CEDR Working Paper. WP #2014-6

ERIC Educational Resources Information Center

Long, Mark C.; Goldhaber, Dan; Huntington-Klein, Nick

2014-01-01

We find statistically significant relationships between changes in wages by occupation and subsequent changes in college majors completed in associated fields. College majors (defined at a detailed level) are most strongly related to wages observed three years earlier, when students were college freshmen. The responses to wages vary depending on…
Coupled Semi-Supervised Learning

DTIC Science & Technology

2010-05-01

later in the thesis, in Chapter 5. CPL as a Case Study of Coupled Semi-Supervised Learning The results presented above demonstrate that coupling...EXTRACTION PATTERNS Our answer to the question posed above, then, is that our results with CPL serve as a case study of coupled semi-supervised learning of...that are incompatible with the coupling constraints. Thus, we argue that our results with CPL serve as a case study of coupled semi-supervised
Hox, Wnt, and the evolution of the primary body axis: insights from the early-divergent phyla

PubMed Central

Ryan, Joseph F; Baxevanis, Andreas D

2007-01-01

The subkingdom Bilateria encompasses the overwhelming majority of animals, including all but four early-branching phyla: Porifera, Ctenophora, Placozoa, and Cnidaria. On average, these early-branching phyla have fewer cell types, tissues, and organs, and are considered to be significantly less specialized along their primary body axis. As such, they present an attractive outgroup from which to investigate how evolutionary changes in the genetic toolkit may have contributed to the emergence of the complex animal body plans of the Bilateria. This review offers an up-to-date glimpse of genome-scale comparisons between bilaterians and these early-diverging taxa. Specifically, we examine these data in the context of how they may explain the evolutionary development of primary body axes and axial symmetry across the Metazoa. Next, we re-evaluate the validity and evolutionary genomic relevance of the zootype hypothesis, which defines an animal by a specific spatial pattern of gene expression. Finally, we extend the hypothesis that Wnt genes may be the earliest primary body axis patterning mechanism by suggesting that Hox genes were co-opted into this patterning network prior to the last common ancestor of cnidarians and bilaterians. Reviewed by Pierre Pontarotti, Gáspár Jékely, and L Aravind. For the full reviews, please go to the Reviewers' comments section. PMID:18078518
Orbital migration and the period distribution of exoplanets

NASA Astrophysics Data System (ADS)

Del Popolo, A.; Ercan, N.; Yeşilyurt, I. S.

2005-06-01

We use the model for the migration of planets introduced in Del Popolo et al. (2003, MNRAS, 339, 556) to calculate the observed mass and semimajor axis distribution of extra-solar planets. The assumption that the surface density in planetesimals is proportional to that of gas is relaxed, and in order to describe disc evolution we use a method which, using a series of simplifying assumptions, is able to simultaneously follow the evolution of gas and solid particles for up to 107 ~yr. The distribution of planetesimals obtained after 107 ~yr is used to study the migration rate of a giant planet through the model described in the present paper. The disk and migration models are used to calculate the distribution of planets as function of mass and semimajor axis. The results show that the model can give a reasonable prediction of planets' semi-major axes and mass distribution. In particular there is a pile-up of planets at a ≃ 0.05 AU, a minimum near 0.3 AU, indicating a paucity of planets at that distance, and a rise for semi-major axes larger than 0.3 AU, out to 3 AU. The semi-major axis distribution shows that the more massive planets (typically, masses larger than 4~ M_J) form preferentially in the outer regions and do not migrate much. Intermediate-mass objects migrate more easily whatever the distance at which they form, and that the lighter planets (masses from sub-Saturnian to Jovian) migrate easily.
Theta variation and spatiotemporal scaling along the septotemporal axis of the hippocampus

PubMed Central

Long, Lauren L.; Bunce, Jamie G.; Chrobak, James J.

2015-01-01

Hippocampal theta has been related to locomotor speed, attention, anxiety, sensorimotor integration and memory among other emergent phenomena. One difficulty in understanding the function of theta is that the hippocampus (HPC) modulates voluntary behavior at the same time that it processes sensory input. Both functions are correlated with characteristic changes in theta indices. The current review highlights a series of studies examining theta local field potential (LFP) signals across the septotemporal or longitudinal axis of the HPC. While the theta signal is coherent throughout the entirety of the HPC, the amplitude, but not the frequency, of theta varies significantly across its three-dimensional expanse. We suggest that the theta signal offers a rich vein of information about how distributed neuronal ensembles support emergent function. Further, we speculate that emergent function across the long axis varies with respect to spatiotemporal scale. Thus, septal HPC processes details of the proximal spatiotemporal environment while more temporal aspects process larger spaces and wider time-scales. The degree to which emergent functions are supported by the synchronization of theta across the septotemporal axis is an open question. Our working model is that theta synchrony serves to bind ensembles representing varying resolutions of spatiotemporal information at interdependent septotemporal areas of the HPC. Such synchrony and cooperative interactions along the septotemporal axis likely support memory formation and subsequent consolidation and retrieval. PMID:25852496
Identification of Time-Varying Pilot Control Behavior in Multi-Axis Control Tasks

NASA Technical Reports Server (NTRS)

Zaal, Peter M. T.; Sweet, Barbara T.

2012-01-01

Recent developments in fly-by-wire control architectures for rotorcraft have introduced new interest in the identification of time-varying pilot control behavior in multi-axis control tasks. In this paper a maximum likelihood estimation method is used to estimate the parameters of a pilot model with time-dependent sigmoid functions to characterize time-varying human control behavior. An experiment was performed by 9 general aviation pilots who had to perform a simultaneous roll and pitch control task with time-varying aircraft dynamics. In 8 different conditions, the axis containing the time-varying dynamics and the growth factor of the dynamics were varied, allowing for an analysis of the performance of the estimation method when estimating time-dependent parameter functions. In addition, a detailed analysis of pilots adaptation to the time-varying aircraft dynamics in both the roll and pitch axes could be performed. Pilot control behavior in both axes was significantly affected by the time-varying aircraft dynamics in roll and pitch, and by the growth factor. The main effect was found in the axis that contained the time-varying dynamics. However, pilot control behavior also changed over time in the axis not containing the time-varying aircraft dynamics. This indicates that some cross coupling exists in the perception and control processes between the roll and pitch axes.
The Collaborative Longitudinal Personality Disorders Study: baseline Axis I/II and II/II diagnostic co-occurrence.

PubMed

McGlashan, T H; Grilo, C M; Skodol, A E; Gunderson, J G; Shea, M T; Morey, L C; Zanarini, M C; Stout, R L

2000-10-01

To describe baseline diagnostic co-occurrence in the Collaborative Longitudinal Personality Disorders Study. Six hundred and sixty-eight patients were reliably assessed with diagnostic interviews for DSM-IV Axis I and II disorders to create five groups: Schizotypal (STPD), Borderline (BPD), Avoidant (AVPD), Obsessive-Compulsive (OCPD) and Major Depressive Disorder (MDD) without personality disorder (PD). Mean number of Axis I lifetime diagnoses was 3.4; STPD and BPD groups had more diagnoses than AVPD, OCPD, and MDD groups. Significant Axis I co-occurrences emerged for Social Phobia/ AVPD, PTSD/BPD and Substance Use/BPD. Mean number of co-occurring PDs was 1.4; STPD had more than BPD group which had more than AVPD and OCPD groups. Significant PD co-occurrence emerged for: STPD/ Paranoid and Schizoid PDs, BPD with Antisocial and Dependent PDs, and lower frequency for OCPD/Antisocial PD. Diagnostic co-occurrences generally followed base rates, while significant departures resemble those of controlled literature.
Surficial weathering of iron sulfide mine tailings under semi-arid climate.

PubMed

Hayes, Sarah M; Root, Robert A; Perdrial, Nicolas; Maier, Raina; Chorover, Jon

2014-09-15

Mine wastes introduce anthropogenic weathering profiles to the critical zone that often remain unvegetated for decades after mining cessation. As such, they are vulnerable to wind and water dispersion of particulate matter to adjacent ecosystems and residential communities. In sulfide-rich ore tailings, propagation to depth of the oxidative weathering front controls the depth-variation in speciation of major and trace elements. Despite the prevalence of surficial mine waste deposits in arid regions of the globe, few prior studies have been conducted to resolve the near-surface profile of sulfide ore tailings weathered under semi-arid climate. We investigated relations between gossan oxidative reaction-front propagation and the molecular speciation of iron and sulfur in tailings subjected to weathering under semi-arid climate at an EPA Superfund Site in semi-arid central Arizona (USA). Here we report a multi-method data set combining wet chemical and synchrotron-based X-ray diffraction (XRD) and X-ray absorption near-edge spectroscopy (XANES) methods to resolve the tight coupling of iron (Fe) and sulfur (S) geochemical changes in the top 2 m of tailings. Despite nearly invariant Fe and S concentration with depth (130-140 and 100-120 g kg -1 , respectively), a sharp redox gradient and distinct morphological change was observed within the top 0.5 m, associated with a progressive oxidative alteration of ferrous sulfides to (oxyhydr)oxides and (hydroxy)sulfates. Transformation is nearly complete in surficial samples. Trends in molecular-scale alteration were co-located with a decrease in pH from 7.3 to 2.3, and shifts in Fe and S lability as measured via chemical extraction. Initial weathering products, ferrihydrite and gypsum, transform to schwertmannite, then jarosite-group minerals with an accompanying decrease in pH. Interestingly, thermodynamically stable phases such as goethite and hematite were not detected in any samples, but ferrihydrite was observed even in
Surficial weathering of iron sulfide mine tailings under semi-arid climate

PubMed Central

Hayes, Sarah M.; Root, Robert A.; Perdrial, Nicolas; Maier, Raina; Chorover, Jon

2014-01-01

Mine wastes introduce anthropogenic weathering profiles to the critical zone that often remain unvegetated for decades after mining cessation. As such, they are vulnerable to wind and water dispersion of particulate matter to adjacent ecosystems and residential communities. In sulfide-rich ore tailings, propagation to depth of the oxidative weathering front controls the depth-variation in speciation of major and trace elements. Despite the prevalence of surficial mine waste deposits in arid regions of the globe, few prior studies have been conducted to resolve the near-surface profile of sulfide ore tailings weathered under semi-arid climate. We investigated relations between gossan oxidative reaction-front propagation and the molecular speciation of iron and sulfur in tailings subjected to weathering under semi-arid climate at an EPA Superfund Site in semi-arid central Arizona (USA). Here we report a multi-method data set combining wet chemical and synchrotron-based X-ray diffraction (XRD) and X-ray absorption near-edge spectroscopy (XANES) methods to resolve the tight coupling of iron (Fe) and sulfur (S) geochemical changes in the top 2 m of tailings. Despite nearly invariant Fe and S concentration with depth (130–140 and 100–120 g kg−1, respectively), a sharp redox gradient and distinct morphological change was observed within the top 0.5 m, associated with a progressive oxidative alteration of ferrous sulfides to (oxyhydr)oxides and (hydroxy)sulfates. Transformation is nearly complete in surficial samples. Trends in molecular-scale alteration were co-located with a decrease in pH from 7.3 to 2.3, and shifts in Fe and S lability as measured via chemical extraction. Initial weathering products, ferrihydrite and gypsum, transform to schwertmannite, then jarosite-group minerals with an accompanying decrease in pH. Interestingly, thermodynamically stable phases such as goethite and hematite were not detected in any samples, but ferrihydrite was observed even
Navigating the Complexities of Undergraduate Medical Curriculum Change: Change Leaders' Perspectives.

PubMed

Velthuis, Floor; Varpio, Lara; Helmich, Esther; Dekker, Hanke; Jaarsma, A Debbie C

2018-02-06

Changing an undergraduate medical curriculum is a recurring, high-stakes undertaking at medical schools. This study aimed to explore how people leading major curriculum changes conceived of the process of enacting change and the strategies they relied on to succeed in their efforts. The first author individually interviewed nine leaders who were leading or had led the most recent undergraduate curriculum change in one of the eight medical schools in the Netherlands. Interviews were between December 2015 and April 2016, using a semi-structured interview format. Data analysis occurred concurrently with data collection, with themes being constructed inductively from the data. Leaders conceived of curriculum change as a dynamic, complex process. They described three major challenges they had to deal with while navigating this process: the large number of stakeholders championing a multitude of perspectives, dealing with resistance, and steering the change process. Additionally, strategies for addressing these challenges were described. The authors identified an underlying principle informing the work of these leaders: being and remaining aware of emerging situations, and carefully constructing strategies for ensuring the intended outcomes were reached and contributed to the progress of the change process. This empirical, descriptive study enriches the understanding of how institutional leaders navigate the complexities of major medical curriculum changes. The insights serve as a foundation for training and coaching future change leaders. To broaden the understanding of curriculum change processes, future studies could investigate the processes through alternative stakeholder perspectives.Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a "work of the United States Government" for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not
Tilted-axis wobbling in odd-mass nuclei

NASA Astrophysics Data System (ADS)

Budaca, R.

2018-02-01

A triaxial rotor Hamiltonian with a rigidly aligned high-j quasiparticle is treated by a time-dependent variational principle, using angular momentum coherent states. The resulting classical energy function has three unique critical points in a space of generalized conjugate coordinates, which can minimize the energy for specific ordering of the inertial parameters and a fixed angular momentum state. Because of the symmetry of the problem, there are only two unique solutions, corresponding to wobbling motion around a principal axis and, respectively, a tilted axis. The wobbling frequencies are obtained after a quantization procedure and then used to calculate E 2 and M 1 transition probabilities. The analytical results are employed in the study of the wobbling excitations of 135Pr nucleus, which is found to undergo a transition from low angular momentum transverse wobbling around a principal axis toward a tilted-axis wobbling at higher angular momentum.
Disruption of the HPA-axis through corticosterone-release pellets induces robust depressive-like behavior and reduced BDNF levels in mice.

PubMed

Demuyser, Thomas; Bentea, Eduard; Deneyer, Lauren; Albertini, Giulia; Massie, Ann; Smolders, Ilse

2016-07-28

The corticosterone mouse model is widely used in preclinical research towards a better understanding of mechanisms of major depression. One particular administration procedure is the subcutaneous implantation of corticosterone slow-release pellets. In this report we want to provide basic evidence, regarding behavioral changes, neurotransmitter and -modulator levels and some other relevant biomolecules after hypothalamic-pituitary-adrenal-axis distortion. We show that three weeks of corticosterone pellet exposure robustly induces depressive-like but not anxiety-like behavior in mice, accompanied by a significant decrease in hippocampal brain-derived neurotrophic factor levels, at five weeks after the start of treatment. Furthermore there is an overall decrease in plasma corticosterone levels after three weeks of treatment that lasts up until the five weeks' time point. On the other hand, no differences are observed in total monoamine, glutamate or d-serine levels, nor in glucocorticoid receptor expression, in various depression-related brain areas. Altogether this characterization delivers vital information, supplementary to existing literature, regarding the phenotyping of pellet-induced hypothalamic-pituitary-adrenal-axis disruption in mice following three weeks of continuous corticosterone exposure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Disentangling the effects of climate variability and functional change on ecosystem carbon dynamics using semi-empirical modelling

NASA Astrophysics Data System (ADS)

Wu, J.; van der Linden, L.; Lasslop, G.; Carvalhais, N.; Pilegaard, K.; Beier, C.; Ibrom, A.

2012-04-01

The ecosystem carbon balance is affected by both external climatic forcing (e.g. solar radiation, air temperature and humidity) and internal dynamics in the ecosystem functional properties (e.g. canopy structure, leaf photosynthetic capacity and carbohydrate reserve). In order to understand to what extent and at which temporal scale, climatic variability and functional changes regulated the interannual variation (IAV) in the net ecosystem exchange of CO2 (NEE), data-driven analysis and semi-empirical modelling (Lasslop et al. 2010) were performed based on a 13 year NEE record in a temperate deciduous forest (Pilegaard et al 2011, Wu et al. 2012). We found that the sensitivity of carbon fluxes to climatic variability was significantly higher at shorter than at longer time scales and changed seasonally. This implied that the changing distribution of climate anomalies during the vegetation period could have stronger impacts on future ecosystem carbon balances than changes in average climate. At the annual time scale, approximately 80% of the interannual variability in NEE was attributed to the variation in the model parameters, indicating the observed IAV in the carbon dynamics at the investigated site was dominated by changes in ecosystem functioning. In general this study showed the need for understanding the mechanisms of ecosystem functional change. The method can be applied at other sites to explore ecosystem behavior across different plant functional types and climate gradients. Incorporating ecosystem functional change into process based models will reduce the uncertainties in long-term predictions of ecosystem carbon balances in global climate change projections. Acknowledgements. This work was supported by the EU FP7 project CARBO-Extreme, the DTU Climate Centre and the Danish national project ECOCLIM (Danish Council for Strategic Research).
Elo-rating for Tracking Rank Fluctuations after Demographic Changes Involving Semi-free– ranging Rhesus Macaques (Macaca mulatta)

PubMed Central

Wooddell, Lauren J; Kaburu, Stefano SK; Suomi, Stephen J; Dettmer, Amanda M

2017-01-01

Rhesus macaques (Macaca mulatta) are gregarious primates that form despotic societies characterized by frequent and intense aggression. Within long-term social groups, demographic changes may influence hierarchical stability, potentially resulting in conflict and violently abrupt hierarchical changes. This conflict can result in serious implications for animal welfare, and thus, predictive tools would be invaluable to captive managers in determining social instabilities. Using the method Elo-rating to track rank changes and dominance stability, we predicted that demographic changes to a population of semi-free ranging rhesus macaques would result in changes in hierarchical stability. Over a 3 y period, dominance data were recorded on all troop members to track the hierarchy. Throughout the 3 y, significant changes occurred to the population (mainly due to health and colony management reasons; no changes specifically occurred for this study) including permanent removal of a large group of natal males, temporary and permanent removal of top-ranking females, and depositions of top-ranking families. Our retrospective study suggests that removing natal males was beneficial in promoting overall troop stability (that is, stability of dominance relationships), although remaining males opportunistically attempted to increase in rank, perhaps due to limited competition. Our results also suggest that removing top-ranking females, even temporarily, destabilized dominance relationships; consequently adjacently ranked females opportunistically increased in Elo-rating, both before and after the depositions of the α families. Thus, these challenges to the established hierarchy can be predicted by increases in Elo-rating within the β families after demographic changes to the α families. Our results suggest that the presence of natal males and the removal of top-ranking females should be minimized to maintain stable dominance relationships. In addition, longitudinal data
Embracing Non-Tenure Track Faculty: Changing Campuses for the New Faculty Majority

ERIC Educational Resources Information Center

Kezar, Adrianna, Ed.

2012-01-01

The nature of the higher education faculty workforce is radically and fundamentally changing from primarily full-time tenured faculty to non-tenure track faculty. This new faculty majority faces common challenges, including short-term contracts, limited support on campus, and lack of a professional career track. "Embracing Non-Tenure Track…
[Changes in prices of taxed sugar-sweetened beverages and nonessential energy dense food in rural and semi-rural areas in Mexico].

PubMed

Colchero, M Arantxa; Zavala, J Alejandro; Batis, Carolina; Shamah-Levy, Teresa; Rivera-Dommarco, Juan A

2017-01-01

To estimate changes in prices associated with the implementation of the tax to sugar sweetened beverages (SSB) and to nonessential energy dense food in 2014. Price data were collected in rural and semi-rural areas in December 2013, and April and December 2014. Fixed effects models were used to estimate changes in prices of beverages and nonessential energy dense food, stratified by region, retailer and package size. The SSB tax did not pass completely through prices: prices increased on average 0.73 pesos per liter. For nonessential energy dense food, the tax passed completely or was overshifted for cookies, cereal bars and cereal boxes. The potential effect of the taxes on consumption could be attenuated in rural areas as the pass through prices was incomplete.
Off-axis points encoding/decoding with orbital angular momentum spectrum

PubMed Central

Chu, Jiaqi; Chu, Daping; Smithwitck, Quinn

2017-01-01

Encoding/decoding off-axis points with discrete orbital angular momentum (OAM) modes is investigated. On-axis Laguerre-Gaussian (LG) beams are expanded into off-axis OAM spectra, with which off-axis points are encoded. The influence of the mode and the displacement of the LG beam on the spread of the OAM spectrum is analysed. The results show that not only the conventional on-axis point, but also off-axis points, can be encoded and decoded with OAM of light. This is confirmed experimentally. The analytical result here provides a solid foundation to use OAM modes to encode two-dimensional high density information for multiplexing and to analyse the effect of mis-alignment in practical OAM applications. PMID:28272543
Identifying Source Water and Flow Paths in a Semi-Arid Watershed

NASA Astrophysics Data System (ADS)

Gulvin, C. J.; Miller, S. N.

2016-12-01

Processes controlling water delivery to perennial streams in the semi-arid mountain west are poorly understood, yet necessary to characterize water distribution across the landscape and better protect and manage diminishing water resources. Stream water chemistry profiling and hydrograph separation using stable isotopes can help identify source waters. Weekly stream water samples tested for stable water isotope fractionations, and major cations and anions at seven sites collocated with continuously recording stream depth gauges within a small watershed in southeastern Wyoming is a necessary first-step to identifying seasonally changing source water and flow paths. Sample results will help establish appropriate end members for a mixing analysis, as well as, characterize flow path heterogeneity, transit time distributions, and landscape selectively features. Hourly stream sampling during late-summer thunderstorms and rapid spring melt will help demonstrate if and how stream discharge change is affected by the two different events. Soil water and water extracted from tree xylem will help resolve how water is partitioned in the first 10m of the subsurface. In the face of land use change and a growing demand for water in the area, understanding how the water in small mountain streams is sustained is crucial for the future of agriculture, municipal water supplies, and countless ecosystem services.

Changes in electrocardiographic findings after closed thoracostomy in patients with spontaneous pneumothorax

PubMed Central

Lee, Wonjae; Lee, Yoonje; Kim, Changsun; Choi, Hyuk Joong; Kang, Bossng; Lim, Tae Ho; Oh, Jaehoon; Kang, Hyunggoo; Shin, Junghun

2017-01-01

Objective We aimed to describe electrocardiographic (ECG) findings in spontaneous pneumothorax patients before and after closed thoracostomy. Methods This is a retrospective study which included patients with spontaneous pneumothorax who presented to an emergency department of a tertiary urban hospital from February 2005 to March 2015. The primary outcome was a difference in ECG findings between before and after closed thoracostomy. We specifically investigated the following ECG elements: PR, QRS, QTc, axis, ST segments, and R waves in each lead. The secondary outcomes were change in ST segment in any lead and change in axis after closed thoracostomy. Results There were two ECG elements which showed statistically significant difference after thoracostomy. With right pneumothorax volume of greater than 80%, QTc and the R waves in aVF and V5 significantly changed after thoracostomy. With left pneumothorax volume between 31% and 80%, the ST segment in V2 and the R wave in V1 significantly changed after thoracostomy. However, majority of ECG elements did not show statistically significant alteration after thoracostomy. Conclusion We found only minor changes in ECG after closed thoracostomy in spontaneous pneumothorax patients. PMID:28435901
Erosion of Pelton buckets and changes in turbine efficiency measured in the HPP Fieschertal

NASA Astrophysics Data System (ADS)

Abgottspon, A.; Staubli, T.; Felix, D.

2016-11-01

Geometrical changes and material loss of Pelton turbine runners as well as changes in turbine efficiency were measured at HPP Fieschertal in Valais, Switzerland. The HPP is equipped with two horizontal axis Pelton units, with each 32 MW nominal power, 7.5 m3/s design discharge, 515 m head and two injectors. The injectors and the buckets are hard-coated. Hydro-abrasive erosion was quantified based on repeated measurements on two runner buckets using (i) 3d-scanning and (ii) a coating thickness gauge. Changes in efficiency were measured by applying the sliding needle procedure. In addition to these periodically performed measurements, efficiency was also continuously monitored. The highest erosion rate was measured during the first half of the sediment season 2012 including a major sediment transport event. Because the runner was not fully reconditioned at the beginning of this season, progressive damages occurred. After the event, a splitter width of 10 mm was measured, corresponding to 1.5 % of the inner bucket width. The cut-outs were eroded by up to 9 mm towards the axis. The efficiency reductions ranged from 1 % in the year with the major sediment transport event to insignificant differences in 2014, when the sediment load was small and only little hydro-abrasive erosion occurred.
Structure and properties of semi-interpenetrating network hydrogel based on starch.

PubMed

Zhu, Baodong; Ma, Dongzhuo; Wang, Jian; Zhang, Shuang

2015-11-20

Starch-g-P(acrylic acid-co-acrylamide)/PVA semi-interpenetrating network (semi-IPN) hydrogels were prepared by aqueous solution polymerization method. Starch grafting copolymerization reaction, semi-IPN structure and crystal morphology were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The PVA in the form of partial crystallization distributing in the gel matrix uniformly were observed by Field emission scanning electron microscope (FESEM). The space network structure, finer microstructure and pore size in the interior of hydrogel were presented by biomicroscope. The results demonstrated that absorption ratio of water and salt generated different degree changes with the effect of PVA. In addition, the mechanical strength of hydrogel was improved. Copyright © 2015 Elsevier Ltd. All rights reserved.
The Hypothalamic-Pituitary-Adrenal Axis and Anesthetics: A Review.

PubMed

Besnier, Emmanuel; Clavier, Thomas; Compere, Vincent

2017-04-01

The hypothalamic-pituitary-adrenal (HPA) axis is essential for human adaptation to stress. However, many anesthetic agents may interfere with the activity of this axis. Although etomidate is known for its suppressive effect on HPA axis function, in vitro evidence suggests that many other drugs used in anesthesia care may also interfere with HPA activity. In this review, we discuss the mechanisms by which all HPA axis activity may be altered during anesthesia and critical care and focus on the impact of hypnotic and analgesic drugs.
Activation of the Hypothalamic-Pituitary-Adrenal (HPA) Axis Following Extended Exposure to Atrazine (ATR)

EPA Science Inventory

While it is known that adrenal steroids impact reproduction and a variety of other physiological and behavioral fimctions, disruption of the HPA-axis is not typically considered in toxicological studies. Here we characterize changes in basal corticosterone (CORT) and progesterone...
Activation of the Hypothalamic-Pituitary-Adrenal (HPA) Axis Following Extended Exposure to Atrazine (ATR)###

EPA Science Inventory

While it is known that adrenal steroids impact reproduction and a variety of other physiological and behavioral functions, disruption of the HPA-axis is not typically considered in toxicological studies. Here we characterize changes in basal corticosterone (CORT) and progesterone...
Microbiota-Brain-Gut Axis and Neurodegenerative Diseases.

PubMed

Quigley, Eamonn M M

2017-10-17

The purposes of this review were as follows: first, to provide an overview of the gut microbiota and its interactions with the gut and the central nervous system (the microbiota-gut-brain axis) in health, second, to review the relevance of this axis to the pathogenesis of neurodegenerative diseases, such as Parkinson's disease, and, finally, to assess the potential for microbiota-targeted therapies. Work on animal models has established the microbiota-gut-brain axis as a real phenomenon; to date, the evidence for its operation in man has been limited and has been confronted by considerable logistical challenges. Animal and translational models have incriminated a disturbed gut microbiota in a number of CNS disorders, including Parkinson's disease; data from human studies is scanty. While a theoretical basis can be developed for the use of microbiota-directed therapies in neurodegenerative disorders, support is yet to come from high-quality clinical trials. In theory, a role for the microbiota-gut-brain axis is highly plausible; clinical confirmation is awaited.
HPA-axis and inflammatory reactivity to acute stress is related with basal HPA-axis activity.

PubMed

Chen, Xuejie; Gianferante, Danielle; Hanlin, Luke; Fiksdal, Alexander; Breines, Juliana G; Thoma, Myriam V; Rohleder, Nicolas

2017-04-01

Inflammation is drawing attention as pathway between psychosocial stress and health, and basal HPA axis activity has been suggested to exert a consistent regulatory influence on peripheral inflammation. Here we studied the relationship between basal HPA axis activity and inflammatory and HPA axis acute stress reactivity. We recruited 48 healthy individuals and collected saliva for diurnal cortisol sampling at 6 points. Participants were previously exposed to the Trier Social Stress Test (TSST) on two consecutive days. Plasma interleukin-6 (IL-6) and salivary cortisol reactivity to acute stress were measured, and their relationships with basal HPA axis activity were analyzed. Steeper cortisol awakening response (CAR) linear increase was related with stronger cortisol stress reactivity (γ=0.015; p=0.042) and marginally significantly with greater habituation (γ=0.01; p=0.066). Greater curvilinearity of CAR was related with stronger cortisol reactivity (γ=-0.014; p=0.021) and greater cortisol habituation (γ=-0.011; p=0.006). Steeper daily linear decline was related with significant or marginally significantly stronger cortisol and IL-6 reactivity (cortisol: γ=-0.0004; p=0.06; IL-6: γ=-0.028; p=0.031) and greater habituation (cortisol: γ=-0.002; p=0.009, IL-6: γ=-0.015; p=0.033). Greater curvilinearity of daily decline was related with stronger IL-6 reactivity (γ=0.002; p=0.024) and also greater cortisol and IL-6 habituation (cortisol: γ=0.00009; p=0.03, IL-6: γ=0.001; p=0.024). Patterns of basal HPA axis activity that are related with healthier outcomes were found to be related with stronger initial cortisol and IL-6 reactivity and greater habituation. This is an important step in understanding the long-term health implications of acute stress responsiveness, and future studies should employ longitudinal designs to identify the direction of these relationships. Copyright © 2017 Elsevier Ltd. All rights reserved.
A Computational Model of the Rainbow Trout Hypothalamus-Pituitary-Ovary-Liver Axis

PubMed Central

Gillies, Kendall; Krone, Stephen M.; Nagler, James J.; Schultz, Irvin R.

2016-01-01

Reproduction in fishes and other vertebrates represents the timely coordination of many endocrine factors that culminate in the production of mature, viable gametes. In recent years there has been rapid growth in understanding fish reproductive biology, which has been motivated in part by recognition of the potential effects that climate change, habitat destruction and contaminant exposure can have on natural and cultured fish populations. New approaches to understanding the impacts of these stressors are being developed that require a systems biology approach with more biologically accurate and detailed mathematical models. We have developed a multi-scale mathematical model of the female rainbow trout hypothalamus-pituitary-ovary-liver axis to use as a tool to help understand the functioning of the system and for extrapolation of laboratory findings of stressor impacts on specific components of the axis. The model describes the essential endocrine components of the female rainbow trout reproductive axis. The model also describes the stage specific growth of maturing oocytes within the ovary and permits the presence of sub-populations of oocytes at different stages of development. Model formulation and parametrization was largely based on previously published in vivo and in vitro data in rainbow trout and new data on the synthesis of gonadotropins in the pituitary. Model predictions were validated against several previously published data sets for annual changes in gonadotropins and estradiol in rainbow trout. Estimates of select model parameters can be obtained from in vitro assays using either quantitative (direct estimation of rate constants) or qualitative (relative change from control values) approaches. This is an important aspect of mathematical models as in vitro, cell-based assays are expected to provide the bulk of experimental data for future risk assessments and will require quantitative physiological models to extrapolate across biological scales. PMID
A Computational Model of the Rainbow Trout Hypothalamus-Pituitary-Ovary-Liver Axis.

PubMed

Gillies, Kendall; Krone, Stephen M; Nagler, James J; Schultz, Irvin R

2016-04-01

Reproduction in fishes and other vertebrates represents the timely coordination of many endocrine factors that culminate in the production of mature, viable gametes. In recent years there has been rapid growth in understanding fish reproductive biology, which has been motivated in part by recognition of the potential effects that climate change, habitat destruction and contaminant exposure can have on natural and cultured fish populations. New approaches to understanding the impacts of these stressors are being developed that require a systems biology approach with more biologically accurate and detailed mathematical models. We have developed a multi-scale mathematical model of the female rainbow trout hypothalamus-pituitary-ovary-liver axis to use as a tool to help understand the functioning of the system and for extrapolation of laboratory findings of stressor impacts on specific components of the axis. The model describes the essential endocrine components of the female rainbow trout reproductive axis. The model also describes the stage specific growth of maturing oocytes within the ovary and permits the presence of sub-populations of oocytes at different stages of development. Model formulation and parametrization was largely based on previously published in vivo and in vitro data in rainbow trout and new data on the synthesis of gonadotropins in the pituitary. Model predictions were validated against several previously published data sets for annual changes in gonadotropins and estradiol in rainbow trout. Estimates of select model parameters can be obtained from in vitro assays using either quantitative (direct estimation of rate constants) or qualitative (relative change from control values) approaches. This is an important aspect of mathematical models as in vitro, cell-based assays are expected to provide the bulk of experimental data for future risk assessments and will require quantitative physiological models to extrapolate across biological scales.
A psychology of the human brain–gut–microbiome axis

PubMed Central

Allen, Andrew P.; Dinan, Timothy G.; Clarke, Gerard

2017-01-01

Abstract In recent years, we have seen increasing research within neuroscience and biopsychology on the interactions between the brain, the gastrointestinal tract, the bacteria within the gastrointestinal tract, and the bidirectional relationship between these systems: the brain–gut–microbiome axis. Although research has demonstrated that the gut microbiota can impact upon cognition and a variety of stress‐related behaviours, including those relevant to anxiety and depression, we still do not know how this occurs. A deeper understanding of how psychological development as well as social and cultural factors impact upon the brain–gut–microbiome axis will contextualise the role of the axis in humans and inform psychological interventions that improve health within the brain–gut–microbiome axis. Interventions ostensibly aimed at ameliorating disorders in one part of the brain–gut–microbiome axis (e.g., psychotherapy for depression) may nonetheless impact upon other parts of the axis (e.g., microbiome composition and function), and functional gastrointestinal disorders such as irritable bowel syndrome represent a disorder of the axis, rather than an isolated problem either of psychology or of gastrointestinal function. The discipline of psychology needs to be cognisant of these interactions and can help to inform the future research agenda in this emerging field of research. In this review, we outline the role psychology has to play in understanding the brain–gut–microbiome axis, with a focus on human psychology and the use of research in laboratory animals to model human psychology. PMID:28804508
A psychology of the human brain-gut-microbiome axis.

PubMed

Allen, Andrew P; Dinan, Timothy G; Clarke, Gerard; Cryan, John F

2017-04-01

In recent years, we have seen increasing research within neuroscience and biopsychology on the interactions between the brain, the gastrointestinal tract, the bacteria within the gastrointestinal tract, and the bidirectional relationship between these systems: the brain-gut-microbiome axis. Although research has demonstrated that the gut microbiota can impact upon cognition and a variety of stress-related behaviours, including those relevant to anxiety and depression, we still do not know how this occurs. A deeper understanding of how psychological development as well as social and cultural factors impact upon the brain-gut-microbiome axis will contextualise the role of the axis in humans and inform psychological interventions that improve health within the brain-gut-microbiome axis. Interventions ostensibly aimed at ameliorating disorders in one part of the brain-gut-microbiome axis (e.g., psychotherapy for depression) may nonetheless impact upon other parts of the axis (e.g., microbiome composition and function), and functional gastrointestinal disorders such as irritable bowel syndrome represent a disorder of the axis, rather than an isolated problem either of psychology or of gastrointestinal function. The discipline of psychology needs to be cognisant of these interactions and can help to inform the future research agenda in this emerging field of research. In this review, we outline the role psychology has to play in understanding the brain-gut-microbiome axis, with a focus on human psychology and the use of research in laboratory animals to model human psychology.
Quantitative DIC microscopy using an off-axis self-interference approach.

PubMed

Fu, Dan; Oh, Seungeun; Choi, Wonshik; Yamauchi, Toyohiko; Dorn, August; Yaqoob, Zahid; Dasari, Ramachandra R; Feld, Michael S

2010-07-15

Traditional Normarski differential interference contrast (DIC) microscopy is a very powerful method for imaging nonstained biological samples. However, one of its major limitations is the nonquantitative nature of the imaging. To overcome this problem, we developed a quantitative DIC microscopy method based on off-axis sample self-interference. The digital holography algorithm is applied to obtain quantitative phase gradients in orthogonal directions, which leads to a quantitative phase image through a spiral integration of the phase gradients. This method is practically simple to implement on any standard microscope without stringent requirements on polarization optics. Optical sectioning can be obtained through enlarged illumination NA.
Iron and sulfur geochemistry in semi-arid mangrove soils (Ceará, Brazil) in relation to seasonal changes and shrimp farming effluents.

PubMed

Nóbrega, G N; Ferreira, T O; Romero, R E; Marques, A G B; Otero, X L

2013-09-01

Iron and sulfur are key elements in the biogeochemistry of estuarine soils, in which Fe and sulfate reduction (SR) pathways are important for organic matter decomposition. In the semi-arid coast of NE Brazil, mangroves are characterized by large seasonal variations in weather and the presence of numerous shrimp farms. The objective was to determine the impacts of shrimp farm effluents on iron and sulfur geochemistry in mangrove soils under the semi-arid climate of NE Brazil. A seasonal study was made of two mangrove forest soils (SF, a mangrove forest that directly receives wastewater from shrimp ponds and CS, a control site). Pyrite Fe, oxyhydroxides Fe, acid volatile sulfide, degree of pyritization (DOP), pH, Eh, total organic carbon (TOC) and total S were determined. There was a clear decrease in pyritic Fe and DOP in the SF soils, which may be related to the anaerobic oxidation of pyrite coupled with nitrate reduction, or to the dominance of denitrification over SR. Lower TOC contents in the SF site suggest that below ground decomposition increased in response to eutrophication. The seasonal variations led to important changes in the semi-arid mangrove soils. During the dry period, both soils experienced oxidizing conditions with remarkable loss of reduced and oxidized forms of Fe, which may have important environmental implications as Fe is biolimiting for marine primary production. The data show that both factors (seasonal weather variations and shrimp effluents) play important roles in the geochemical processes that occur in these soils and, thus, may affect their functioning and maintenance.
Multifunctional semi-interpenetrating polymer network-nanoencapsulated cathode materials for high-performance lithium-ion batteries.

PubMed

Kim, Ju-Myung; Park, Jang-Hoon; Lee, Chang Kee; Lee, Sang-Young

2014-04-08

As a promising power source to boost up advent of next-generation ubiquitous era, high-energy density lithium-ion batteries with reliable electrochemical properties are urgently requested. Development of the advanced lithium ion-batteries, however, is staggering with thorny problems of performance deterioration and safety failures. This formidable challenge is highly concerned with electrochemical/thermal instability at electrode material-liquid electrolyte interface, in addition to structural/chemical deficiency of major cell components. Herein, as a new concept of surface engineering to address the abovementioned interfacial issue, multifunctional conformal nanoencapsulating layer based on semi-interpenetrating polymer network (semi-IPN) is presented. This unusual semi-IPN nanoencapsulating layer is composed of thermally-cured polyimide (PI) and polyvinyl pyrrolidone (PVP) bearing Lewis basic site. Owing to the combined effects of morphological uniqueness and chemical functionality (scavenging hydrofluoric acid that poses as a critical threat to trigger unwanted side reactions), the PI/PVP semi-IPN nanoencapsulated-cathode materials enable significant improvement in electrochemical performance and thermal stability of lithium-ion batteries.
Multifunctional semi-interpenetrating polymer network-nanoencapsulated cathode materials for high-performance lithium-ion batteries

NASA Astrophysics Data System (ADS)

Kim, Ju-Myung; Park, Jang-Hoon; Lee, Chang Kee; Lee, Sang-Young

2014-04-01

As a promising power source to boost up advent of next-generation ubiquitous era, high-energy density lithium-ion batteries with reliable electrochemical properties are urgently requested. Development of the advanced lithium ion-batteries, however, is staggering with thorny problems of performance deterioration and safety failures. This formidable challenge is highly concerned with electrochemical/thermal instability at electrode material-liquid electrolyte interface, in addition to structural/chemical deficiency of major cell components. Herein, as a new concept of surface engineering to address the abovementioned interfacial issue, multifunctional conformal nanoencapsulating layer based on semi-interpenetrating polymer network (semi-IPN) is presented. This unusual semi-IPN nanoencapsulating layer is composed of thermally-cured polyimide (PI) and polyvinyl pyrrolidone (PVP) bearing Lewis basic site. Owing to the combined effects of morphological uniqueness and chemical functionality (scavenging hydrofluoric acid that poses as a critical threat to trigger unwanted side reactions), the PI/PVP semi-IPN nanoencapsulated-cathode materials enable significant improvement in electrochemical performance and thermal stability of lithium-ion batteries.
Development of a precision, six-axis laboratory dynamometer

NASA Technical Reports Server (NTRS)

Champagne, P. J.; Cordova, S. A.; Jacoby, M. S.; Lorell, K. R.

1992-01-01

This paper describes the design, fabrication, test, and operation of a unique six axis force/torque dynamometer The specimen table used to hold components under test is supported in a full six axis kinematic mount. Support struts fabricated from high strength steel with special integral two axis flexures link the specimen table to the load cell transducers. Realtime force/torque coordinate transform, root mean squared calculation, and data averaging, and color six axis display with controllable scaling are provided by a specially programmed desktop computer. The extensive structural analysis and design optimization required to obtain a stiff, well damped, lightweight structure is described in detail. Geometric optimization of the kinematic mount and fabrication details of the struts are also described.
US major crops’ uncertain climate change risks and greenhouse gas mitigation benefits

DOE PAGES

Wing, Ian Sue; Monier, Erwan; Stern, Ari; ...

2015-10-28

In this study, we estimate the costs of climate change to US agriculture, and associated potential benefits of abating greenhouse gas emissions. Five major crops' yield responses to climatic variation are modeled empirically, and the results combined with climate projections for a no-policy, high-warming future, as well as moderate and stringent mitigation scenarios. Unabated warming reduces yields of wheat and soybeans by 2050, and cotton by 2100, but moderate warming increases yields of all crops except wheat. Yield changes are monetized using the results of economic simulations within an integrated climate-economy modeling framework. Uncontrolled warming's economic effects on major cropsmore » are slightly positive—annual benefits <$4 B. These are amplified by emission reductions, but subject to diminishing returns—by 2100 reaching $17 B under moderate mitigation, but only $7 B with stringent mitigation. Costs and benefits are sensitive to irreducible uncertainty about the fertilization effects of elevated atmospheric carbon dioxide, without which unabated warming incurs net costs of up to $18 B, generating benefits to moderate (stringent) mitigation as large as $26 B ($20 B).« less
US major crops’ uncertain climate change risks and greenhouse gas mitigation benefits

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

Wing, Ian Sue; Monier, Erwan; Stern, Ari

In this study, we estimate the costs of climate change to US agriculture, and associated potential benefits of abating greenhouse gas emissions. Five major crops' yield responses to climatic variation are modeled empirically, and the results combined with climate projections for a no-policy, high-warming future, as well as moderate and stringent mitigation scenarios. Unabated warming reduces yields of wheat and soybeans by 2050, and cotton by 2100, but moderate warming increases yields of all crops except wheat. Yield changes are monetized using the results of economic simulations within an integrated climate-economy modeling framework. Uncontrolled warming's economic effects on major cropsmore » are slightly positive—annual benefits <$4 B. These are amplified by emission reductions, but subject to diminishing returns—by 2100 reaching $17 B under moderate mitigation, but only $7 B with stringent mitigation. Costs and benefits are sensitive to irreducible uncertainty about the fertilization effects of elevated atmospheric carbon dioxide, without which unabated warming incurs net costs of up to $18 B, generating benefits to moderate (stringent) mitigation as large as $26 B ($20 B).« less
Querying Semi-Structured Data

NASA Technical Reports Server (NTRS)

Abiteboul, Serge

1997-01-01

The amount of data of all kinds available electronically has increased dramatically in recent years. The data resides in different forms, ranging from unstructured data in the systems to highly structured in relational database systems. Data is accessible through a variety of interfaces including Web browsers, database query languages, application-specic interfaces, or data exchange formats. Some of this data is raw data, e.g., images or sound. Some of it has structure even if the structure is often implicit, and not as rigid or regular as that found in standard database systems. Sometimes the structure exists but has to be extracted from the data. Sometimes also it exists but we prefer to ignore it for certain purposes such as browsing. We call here semi-structured data this data that is (from a particular viewpoint) neither raw data nor strictly typed, i.e., not table-oriented as in a relational model or sorted-graph as in object databases. As will seen later when the notion of semi-structured data is more precisely de ned, the need for semi-structured data arises naturally in the context of data integration, even when the data sources are themselves well-structured. Although data integration is an old topic, the need to integrate a wider variety of data- formats (e.g., SGML or ASN.1 data) and data found on the Web has brought the topic of semi-structured data to the forefront of research. The main purpose of the paper is to isolate the essential aspects of semi- structured data. We also survey some proposals of models and query languages for semi-structured data. In particular, we consider recent works at Stanford U. and U. Penn on semi-structured data. In both cases, the motivation is found in the integration of heterogeneous data.

A Semi-Batch Reactor Experiment for the Undergraduate Laboratory

ERIC Educational Resources Information Center

Derevjanik, Mario; Badri, Solmaz; Barat, Robert

2011-01-01

This experiment and analysis offer an economic yet challenging semi-batch reactor experience. Household bleach is pumped at a controlled rate into a batch reactor containing pharmaceutical hydrogen peroxide solution. Batch temperature, product molecular oxygen, and the overall change in solution conductivity are metered. The reactor simulation…
Semi-transparent shock model for major solar energetic particle events

NASA Astrophysics Data System (ADS)

Kocharov, Leon

2014-05-01

Production of solar energetic particles in major events typically comprises two stages: (i) the initial stage associated with shocks and magnetic reconnection in solar corona and (ii) the main stage associated with the CME-bow shock in solar wind. The coronal emission of energetic particles from behind the interplanetary shock wave continues for about one hour , being not shielded by the CME shock in solar wind and having the prompt access to particle detectors at 1 AU. On occasion of two well-separated solar eruptions from the same active region, the newly accelerated solar particles may be emitted well behind the previous CME, and those solar particles may penetrate through the interplanetary shock of the previous CME to arrive at the Earth's orbit without significant delay, which is another evidence that high-energy particles from the solar corona can penetrate through travelling interplanetary shocks. Diffusive shock acceleration is fast only if the particle mean free path near the shock is small. The small mean free path (high turbulence level), however, implies that energetic particles from coronal sources could not penetrate through the interplanetary shock, and even the particles accelerated by the interplanetary shock itself could not escape to its far upstream region. If so, they could not be promptly observed at 1 AU. However, high-energy particles in major solar events are detected well before the shock arrival at 1 AU. The theoretical difficulty can be obviated in the framework of the proposed model of a "semitransparent" shock. As in situ plasma observations indicate, the turbulence energy levels in neighboring magnetic tubes of solar wind may differ from each other by more than one order of magnitude. Such an intermittence of coronal and solar wind plasmas can affect energetic particle acceleration in coronal and interplanetary shocks. The new modeling incorporates particle acceleration in the shock front and the particle transport both in parallel
Location of aerodynamic noise sources from a 200 kW vertical-axis wind turbine

NASA Astrophysics Data System (ADS)

Ottermo, Fredric; Möllerström, Erik; Nordborg, Anders; Hylander, Jonny; Bernhoff, Hans

2017-07-01

Noise levels emitted from a 200 kW H-rotor vertical-axis wind turbine have been measured using a microphone array at four different positions, each at a hub-height distance from the tower. The microphone array, comprising 48 microphones in a spiral pattern, allows for directional mapping of the noise sources in the range of 500 Hz to 4 kHz. The produced images indicate that most of the noise is generated in a narrow azimuth-angle range, compatible with the location where increased turbulence is known to be present in the flow, as a result of the previous passage of a blade and its support arms. It is also shown that a semi-empirical model for inflow-turbulence noise seems to produce noise levels of the correct order of magnitude, based on the amount of turbulence that could be expected from power extraction considerations.
Multiple Scales of Representation along the Hippocampal Anteroposterior Axis in Humans.

PubMed

Brunec, Iva K; Bellana, Buddhika; Ozubko, Jason D; Man, Vincent; Robin, Jessica; Liu, Zhong-Xu; Grady, Cheryl; Rosenbaum, R Shayna; Winocur, Gordon; Barense, Morgan D; Moscovitch, Morris

2018-06-13

The ability to represent the world accurately relies on simultaneous coarse and fine-grained neural information coding, capturing both gist and detail of an experience. The longitudinal axis of the hippocampus may provide a gradient of representational granularity in spatial and episodic memory in rodents and humans [1-8]. Rodent place cells in the ventral hippocampus exhibit significantly larger place fields and greater autocorrelation than those in the dorsal hippocampus [1, 9-11], which may underlie a coarser and slower changing representation of space [10, 12]. Recent evidence suggests that properties of cellular dynamics in rodents can be captured with fMRI in humans during spatial navigation [13] and conceptual learning [14]. Similarly, mechanisms supporting granularity along the long axis may also be extrapolated to the scale of fMRI signal. Here, we provide the first evidence for separable scales of representation along the human hippocampal anteroposterior axis during navigation and rest by showing (1) greater similarity among voxel time courses and (2) higher temporal autocorrelation in anterior hippocampus (aHPC), relative to posterior hippocampus (pHPC), the human homologs of ventral and dorsal rodent hippocampus. aHPC voxels exhibited more similar activity at each time point and slower signal change over time than voxels in pHPC, consistent with place field organization in rodents. Importantly, similarity between voxels was related to navigational strategy and episodic memory. These findings provide evidence that the human hippocampus supports an anterior-to-posterior gradient of coarse-to-fine spatiotemporal representations, suggesting the existence of a cross-species mechanism, whereby lower neural similarity supports more complex coding of experience. Copyright © 2018 Elsevier Ltd. All rights reserved.
Reframing the Teenage Wasteland: Adolescent Microbiota-Gut-Brain Axis.

PubMed

McVey Neufeld, Karen-Anne; Luczynski, Pauline; Dinan, Timothy G; Cryan, John F

2016-04-01

Human adolescence is arguably one of the most challenging periods of development. The young adult is exposed to a variety of stressors and environmental stimuli on a backdrop of significant physiological change and development, which is especially apparent in the brain. It is therefore unsurprising that many psychiatric disorders are first observable during this time. The human intestine is inhabited by trillions of microorganisms, and evidence from both preclinical and clinical research focusing on the established microbiota-gut-brain axis suggests that the etiology and pathophysiology of psychiatric disorders may be influenced by intestinal dysbiosis. Provocatively, many if not all of the challenges faced by the developing teen have a documented impact on these intestinal commensal microbiota. In this review, we briefly summarize what is known about the developing adolescent brain and intestinal microbiota, discuss recent research investigating the microbiota-gut-brain axis during puberty, and propose that pre- and probiotics may prove useful in both the prevention and treatment of psychiatric disorders specifically benefitting the young adult. © The Author(s) 2016.
Reframing the Teenage Wasteland: Adolescent Microbiota-Gut-Brain Axis

PubMed Central

McVey Neufeld, Karen-Anne; Luczynski, Pauline; Dinan, Timothy G.

2016-01-01

Human adolescence is arguably one of the most challenging periods of development. The young adult is exposed to a variety of stressors and environmental stimuli on a backdrop of significant physiological change and development, which is especially apparent in the brain. It is therefore unsurprising that many psychiatric disorders are first observable during this time. The human intestine is inhabited by trillions of microorganisms, and evidence from both preclinical and clinical research focusing on the established microbiota-gut-brain axis suggests that the etiology and pathophysiology of psychiatric disorders may be influenced by intestinal dysbiosis. Provocatively, many if not all of the challenges faced by the developing teen have a documented impact on these intestinal commensal microbiota. In this review, we briefly summarize what is known about the developing adolescent brain and intestinal microbiota, discuss recent research investigating the microbiota-gut-brain axis during puberty, and propose that pre- and probiotics may prove useful in both the prevention and treatment of psychiatric disorders specifically benefitting the young adult. PMID:27254413
Off-axis astigmatism in the isolated chicken crystalline lens.

PubMed

Maier, Felix; Wahl, Siegfried; Schaeffel, Frank

2016-12-01

The chicken eye was previously found to have little off-axis astigmatism which is not explained by its special corneal shape but rather by the optical properties of the crystalline lens. To learn more about lens design, we studied off-axis astigmatism in the chicken lens in situ and compared it to a glass lens of similar power but with homogenous refractive index. After euthanasia, enucleated eye balls were cut in the equatorial plane right behind the scleral ossicles. The anterior segment was placed in a water-filled chamber. Several thin laser beams were projected in two perpendicular meridians through the lens under various eccentricities and the focal lengths were determined. Off-axis astigmatism across the horizontal visual field was determined as the differences in power in the two meridians. The same procedure was used for the glass lens. On-axis, the chicken crystalline lens had slightly more power in the vertical than in the horizontal meridian (-2.8±0.7D (SEM)). Astigmatism flipped sign and increased with eccentricity to reach +6.1±2.1D (SEM) at 33.5deg off-axis, as expected from off-axis astigmatism. Even though this value appears high, it was still 2.5 times lower than in the glass lens. A ZEMAX model of a lens with a homogeneous index and with surface profiles taken of the natural chicken lens revealed even higher levels of off-axis astigmatism. Obviously, the natural chicken lens displays much less off-axis astigmatism than a glass lens with similar power. Since its shape does not explain the low off-axis astigmatism, it must be due to a refined internal refractive index structure. Copyright © 2016 Elsevier Ltd. All rights reserved.
Neuroendocrine Regulation of Anxiety: Beyond the Hypothalamic-Pituitary-Adrenal Axis.

PubMed

Borrow, A P; Stranahan, A M; Suchecki, D; Yunes, R

2016-07-01

The central nervous system regulates and responds to endocrine signals, and this reciprocal relationship determines emotional processing and behavioural anxiety. Although the hypothalamic-pituitary-adrenal (HPA) axis remains the best-characterised system for this relationship, other steroid and peptide hormones are increasingly recognised for their effects on anxiety-like behaviour and reward. The present review examines recent developments related to the role of a number of different hormones in anxiety, including pregnane neurosteroids, gut peptides, neuropeptides and hormonal signals derived from fatty acids. Findings from both basic and clinical studies suggest that these alternative systems may complement or occlude stress-induced changes in anxiety and anxiety-like behaviour. By broadening the scope of mechanisms for depression and anxiety, it may be possible to develop novel strategies to attenuate stress-related psychiatric conditions. The targets for these potential therapies, as discussed in this review, encompass multiple circuits and systems, including those outside of the HPA axis. © 2016 British Society for Neuroendocrinology.
Automated Slicing for a Multi-Axis Metal Deposition System (Preprint)

DTIC Science & Technology

2006-09-01

experimented with different materials like H13 tool steel to build the part. Following the same slicing and scanning toolpath result, there is a geometric...and analysis tool -centroidal axis. Similar to medial axis, it contains geometry and topological information but is significantly computationally...geometry reasoning and analysis tool -centroidal axis. Similar to medial axis, it contains geometry and topological information but is significantly
Microenvironmental change as a mechanism to study global change.

NASA Astrophysics Data System (ADS)

Lortie, C. J.

2016-12-01

Global change is a set of significant processes that influence all aspects of ecosystem functioning and often-natural services within Santa Barbara County. The sensitivity of coastal and urban systems is certainly very high. However, profound changes are also predicted for arid and semi-arid systems globally, and California is no exception. These dryland systems are less buffered by oceanic processes and typically express high inter-annual variation in precipitation and temperatures in addition to perturbations associated with long-term droughts. However, climate estimates and downscaled values can present challenges in providing evidence at the scale relevant to individual species or individuals, and the importance of biotic interactions must be coupled to these estimates in space and time. Coupled indicators of key micro-environmental measures to both positive and negative interactions between foundation species and other organisms provide a metric of buffering capacity and resilience to global change at fine spatial scales. Consequently, the primary objective of this research project is to provide both the a well-articulated, ecologically relevant micro-environmental big data measure of global change within Santa Barbara County and a coupled estimate of concurrent changes in interactions in key species within the region. Shrubs directly and indirectly buffered local changes in the microenvironment thereby functioning as refuges for other species within arid and semi-arid regions subject to dramatic global change drivers. The following major patterns were identified: (i) shrub micro-environments reduce the level of stress and amplitude of variation associated with temperature and moisture, (ii) many plant and animal species including threatened lizards are relatively more common with shrubs within the region, and (iii) the variation in the interaction patterns between species relates to the extent of amelioration provided by shrub-biodiversity complexes within
The Dynamics of a Semi-Arid Region in Response to Climate and Water - Use Policy

NASA Technical Reports Server (NTRS)

Mustard, John F.; Hamburg, Steve; Grant, John A.; Manning, Sara J.; Steinwand, Aaron; Howard, Chris

2000-01-01

The objectives of this project were to determine the response of semi-arid ecosystems to the combined forcings of climate variability and anthropogenic stress. Arid and semi-arid systems encompass close to 40% of the worlds land surface. The ecology of these regions are principally limited by water, and as the water resources wax and wane, so should the health and vigor of the ecosystems. Water, however, is a necessary and critical resource for humans living in these same regions. Thus for many and and semi-arid regions the natural systems and human systems are in direct competition for a limited resource. Increasing competition through development of and and semi-arid regions, export of water resources, as well as potential persistent changes in weather patterns are likely to lead to fundamental changes in carrying capacity, resilience, and ecology of these regions. A detailed understanding of these systems respond to forcing on a regional and local scale is required in order to better prepare for and manage future changes in the availability of water. In the Owens Valley CA, decadal changes in rainfall and increased use of groundwater resources by Los Angles (which derives 60-70% of its water from this region) have resulted in a large-scale experiment on the impacts of these changes in semi-arid ecosystems. This project works directly with the Inyo County Water Department (local water authority) and the Los Angles Department of Water and Power (regional demand on water resources) to understand changes, their causes, and impacts. Very detailed records have been kept for a number of selected sites in the valley which provide essential ground truth. These results are then scaled up through remote sensed data to regions scale to assess large scale patterns and link them to the fundamental decisions regarding the water resources of this region. A fundamental goal is to understand how resilient the native ecosystems are to large changes in water resources. Are they are
Paternal stress exposure alters sperm microRNA content and reprograms offspring HPA stress axis regulation

PubMed Central

Rodgers, Ali B.; Morgan, Christopher P.; Bronson, Stefanie L.; Revello, Sonia; Bale, Tracy L.

2013-01-01

Neuropsychiatric disease frequently presents with an underlying hypo- or hyper- reactivity of the HPA stress axis, suggesting an exceptional vulnerability of this circuitry to external perturbations. Parental lifetime exposures to environmental challenges are associated with increased offspring neuropsychiatric disease risk, and likely contribute to stress dysregulation. While maternal influences have been extensively examined, much less is known regarding the specific role of paternal factors. To investigate the potential mechanisms by which paternal stress may contribute to offspring hypothalamic-pituitary-adrenal (HPA) axis dysregulation, we exposed mice to six weeks of chronic stress prior to breeding. As epidemiological studies support variation in paternal germ cell susceptibility to reprogramming across the lifespan, male stress exposure occurred either throughout puberty or in adulthood. Remarkably, offspring of sires from both paternal stress groups displayed significantly reduced HPA axis stress responsivity. Gene set enrichment analyses in offspring stress regulating brain regions, the paraventricular nucleus (PVN) and the bed nucleus of stria terminalis (BNST), revealed global pattern changes in transcription suggestive of epigenetic reprogramming and consistent with altered offspring stress responsivity, including increased expression of glucocorticoid-responsive genes in the PVN. In examining potential epigenetic mechanisms of germ cell transmission, we found robust changes in sperm miRNA (miR) content, where nine specific miRs were significantly increased in both paternal stress groups. Overall, these results demonstrate that paternal experience across the lifespan can induce germ cell epigenetic reprogramming and impact offspring HPA stress axis regulation, and may therefore offer novel insight into factors influencing neuropsychiatric disease risk. PMID:23699511
Single Vector Calibration System for Multi-Axis Load Cells and Method for Calibrating a Multi-Axis Load Cell

NASA Technical Reports Server (NTRS)

Parker, Peter A. (Inventor)

2003-01-01

A single vector calibration system is provided which facilitates the calibration of multi-axis load cells, including wind tunnel force balances. The single vector system provides the capability to calibrate a multi-axis load cell using a single directional load, for example loading solely in the gravitational direction. The system manipulates the load cell in three-dimensional space, while keeping the uni-directional calibration load aligned. The use of a single vector calibration load reduces the set-up time for the multi-axis load combinations needed to generate a complete calibration mathematical model. The system also reduces load application inaccuracies caused by the conventional requirement to generate multiple force vectors. The simplicity of the system reduces calibration time and cost, while simultaneously increasing calibration accuracy.
Rapid warming accelerates tree growth decline in semi-arid forests of Inner Asia.

PubMed

Liu, Hongyan; Park Williams, A; Allen, Craig D; Guo, Dali; Wu, Xiuchen; Anenkhonov, Oleg A; Liang, Eryuan; Sandanov, Denis V; Yin, Yi; Qi, Zhaohuan; Badmaeva, Natalya K

2013-08-01

Forests around the world are subject to risk of high rates of tree growth decline and increased tree mortality from combinations of climate warming and drought, notably in semi-arid settings. Here, we assess how climate warming has affected tree growth in one of the world's most extensive zones of semi-arid forests, in Inner Asia, a region where lack of data limits our understanding of how climate change may impact forests. We show that pervasive tree growth declines since 1994 in Inner Asia have been confined to semi-arid forests, where growing season water stress has been rising due to warming-induced increases in atmospheric moisture demand. A causal link between increasing drought and declining growth at semi-arid sites is corroborated by correlation analyses comparing annual climate data to records of tree-ring widths. These ring-width records tend to be substantially more sensitive to drought variability at semi-arid sites than at semi-humid sites. Fire occurrence and insect/pathogen attacks have increased in tandem with the most recent (2007-2009) documented episode of tree mortality. If warming in Inner Asia continues, further increases in forest stress and tree mortality could be expected, potentially driving the eventual regional loss of current semi-arid forests. © 2013 John Wiley & Sons Ltd.
Female nurses' burnout symptoms: No association with the Hypothalamic-pituitary-thyroid (HPT) axis.

PubMed

Guo, Yufang; Lam, Louisa; Luo, Yuanhui; Plummer, Virginia; Cross, Wendy; Li, Hui; Yin, Yizhen; Zhang, Jingping

2017-03-01

Across the world, hospital nurses experience a high level of burnout. Exploring biochemical markers of burnout could help to understand physiological changes and may provide useful evidence for preventing burnout symptoms. The current study included 94 female nurses from one Chinese third-level hospital. The Maslach Burnout Inventory-General Survey (MBI-GS) was used to investigate burnout symptoms: emotional exhaustion, cynicism, reduced professional efficacy, as well as the burnout average. The HPT axis was tested by checking blood levels of thyroid-stimulating hormone (TSH), thyroxin (T 4 ) and triiodothyronine (T 3 ). Nonparametric tests showed that no significant difference in biochemical markers was found between the burnout and non-burnout groups. Spearman correlation analysis found that biochemical markers had no significant association with burnout symptoms, except weakly negative associations between reduced professional efficacy and blood pressure and heart rate. These findings show a rather poor correlation of the HPT axis on burnout symptoms. Expanding the biochemical index of the HPT axis, comparing well-defined samples and using longitudinal studies are recommended for further studies. Copyright © 2016 Elsevier Ltd. All rights reserved.
Future Changes in Major Stratospheric Warmings in CCMI Models

NASA Technical Reports Server (NTRS)

Ayarzaguena, B.; Langematz, U.; Polvani, L. M; Abalichin, J.; Akiyoshi, H.; Klekociuk, A.; Michou, M.; Morgenstern, O.; Oman, L.

2015-01-01

Major stratospheric warmings (MSWs) are one of the most important phenomena of wintertime Arctic stratospheric variability. They consist of a warming of the Arctic stratosphere and a deceleration of the polar night jet, triggered by an anomalously high injection of tropospheric wave activity into the stratosphere. Due to the relevance and the impact of MSWs on the tropospheric circulation, several model studies have investigated their potential responses to climate change. However, a wide range of results has been obtained, extending from a future increase in the frequency of MSWs to a decrease. These discrepancies might be explained by different factors such as a competition of radiative and dynamical contributors with opposite effects on the Arctic polar vortex, biases of models to reproduce the related processes, or the metric chosen for the identification of MSWs. In this study, future changes in wintertime Arctic stratospheric variability are examined in order to obtaina more precise picture of future changes in the occurrence of MSWs. In particular, transient REFC2 simulations of different CCMs involved in the Chemistry Climate Model Initiative (CCMI) are used. These simulations extend from 1960 to 2100 and include forcings by halogens and greenhouse gases following the specifications of the CCMI-REF-C2 scenario. Sea surface temperatures (SSTs) and sea-ice distributions are either prescribed from coupled climate model integrations or calculated internally in the case of fully coupled atmosphere-ocean CCMs. Potential changes in the frequency and main characteristics of MSWs in the future are investigated with special focus on the dependence of the results on the criterion for the identification of MSWs and the tropospheric forcing of these phenomena.
A robust correspondence matching algorithm of ground images along the optic axis

NASA Astrophysics Data System (ADS)

Jia, Fengman; Kang, Zhizhong

2013-10-01

Facing challenges of nontraditional geometry, multiple resolutions and the same features sensed from different angles, there are more difficulties of robust correspondence matching for ground images along the optic axis. A method combining SIFT algorithm and the geometric constraint of the ratio of coordinate differences between image point and image principal point is proposed in this paper. As it can provide robust matching across a substantial range of affine distortion addition of change in 3D viewpoint and noise, we use SIFT algorithm to tackle the problem of image distortion. By analyzing the nontraditional geometry of ground image along the optic axis, this paper derivates that for one correspondence pair, the ratio of distances between image point and image principal point in an image pair should be a value not far from 1. Therefore, a geometric constraint for gross points detection is formed. The proposed approach is tested with real image data acquired by Kodak. The results show that with SIFT and the proposed geometric constraint, the robustness of correspondence matching on the ground images along the optic axis can be effectively improved, and thus prove the validity of the proposed algorithm.
Feeding prepubescent gilts a high-fat diet induces molecular changes in the hypothalamus-pituitary-gonadal axis and predicts early timing of puberty.

PubMed

Zhuo, Yong; Zhou, Dongsheng; Che, Lianqiang; Fang, Zhengfeng; Lin, Yan; Wu, De

2014-01-01

The onset of puberty in females has been occurring earlier over the past decades, presumably as a result of improved nutrition in developed countries. However, the underlying molecular mechanisms responsible for the early attainment of puberty as a result of nutrition fortification remain largely unknown. The aim of this study was to evaluate the hormone and gene expression changes in prepubescent gilts fed a high-fat diet to investigate whether these changes could predict the early timing of puberty. Forty gilts were fed a daily basal diet (LE) or a basal diet with an additional 270 g/d or 340 g/d of fat (HE) during the prepubescent phase. Blood samples were collected during the prepubescent phase to detect hormone secretion changes in insulin-like growth factor-1, kisspeptin, estradiol, progesterone, and leptin. The gene expressions at the hypothalamus-pituitary-gonadal axis were examined on day 73 of the experiment (average age on day 177) during the prepubescent phase. An HE diet resulted in accelerated body weight gain and back-fat thickness at the P2 point compared with LE gilts during the prepubescent phase. Gilts that were fed HE diets attained puberty 12 d earlier than LE gilts, and a larger proportion of HE gilts reached puberty at day 180 or 190 of age. A postmortem analysis revealed a promoted development of the uterus and ovary tissue that was characterized by a 53.7% and 29.5% increase in the uterine and ovary weight, respectively, and an increased length of the uterine horn and oviduct tissue in HE gilts. Real-time quantitative polymerase chain reaction revealed that HE gilts had higher Kiss-1, G protein-coupled receptor 54, gonadotropin-releasing hormone and estrogen receptor α mRNA expression levels in the hypothalamic anteroventral periventricular nucleus; the leptin receptor mRNA expression level was higher in the hypothalamic arcuate nucleus and ovary tissue; the insulin-like growth factor-1 receptor expression was higher in the pituitary and
Test/QA Plan for Verification of Semi-Continuous Ambient Air Monitoring Systems - Second Round

EPA Science Inventory

Test/QA Plan for Verification of Semi-Continuous Ambient Air Monitoring Systems - Second Round. Changes reflect performance of second round of testing at new location and with various changes to personnel. Additional changes reflect general improvements to the Version 1 test/QA...
Axis IV--psychosocial and environmental problems--in the DSM-IV.

PubMed

Ramirez, A; Ekselius, L; Ramklint, M

2013-11-01

The aim of this study was to further explore the properties of axis IV in the Diagnostic and statistical manual of mental disorders, 4th edition (DSM-IV). In a naturalistic cross-sectional design, a group (n = 163) of young (18-25 years old) Swedish psychiatric outpatients was assessed according to DSM-IV. Psychosocial and environmental problems/axis IV were evaluated through structured interviewing by a social worker and by self-assessment on a questionnaire. Reliability between professional assessment and self-assessment of axis IV was examined. Concurrent validity of axis IV was also examined. Reliability between professional and self-assessed axis IV was fair to almost perfect, 0.31-0.83, according to prevalence and bias-adjusted kappa. Categories of psychosocial stress and environmental problems were related to the presence of axis I disorders, co-morbidity, personality disorders and decreasing Global Assessment of Functioning (GAF) values. The revised axis IV according to DSM-IV seems to have concurrent validity, but is still hampered by limited reliability. © 2013 John Wiley & Sons Ltd.

A ghrelin-growth hormone axis drives stress-induced vulnerability to enhanced fear

PubMed Central

Meyer, Retsina M.; Burgos-Robles, Anthony; Liu, Elizabeth; Correia, Susana S.; Goosens, Ki A.

2014-01-01

Hormones in the hypothalamus-pituitary-adrenal (HPA) axis mediate many of the bodily responses to stressors, yet there is not a clear relationship between the levels of these hormones and stress-associated mental illnesses such as post-traumatic stress disorder (PTSD). Therefore, other hormones are likely to be involved in this effect of stress. Here we used a rodent model of PTSD in which rats repeatedly exposed to a stressor display heightened fear learning following auditory Pavlovian fear conditioning. Our results show that stress-related increases in circulating ghrelin, a peptide hormone, are necessary and sufficient for stress-associated vulnerability to exacerbated fear learning and these actions of ghrelin occur in the amygdala. Importantly, these actions are also independent of the classic HPA stress axis. Repeated systemic administration of a ghrelin receptor agonist enhanced fear memory but did not increase either corticotropin releasing factor (CRF) or corticosterone. Repeated intra-amygdala infusion of a ghrelin receptor agonist produced a similar enhancement of fear memory. Ghrelin receptor antagonism during repeated stress abolished stress-related enhancement of fear memory without blunting stress-induced corticosterone release. We also examined links between ghrelin and growth hormone (GH), a major downstream effector of the ghrelin receptor. GH protein was upregulated in the amygdala following chronic stress, and its release from amygdala neurons was increased by ghrelin receptor stimulation. Virus-mediated overexpression of GH in the amygdala was also sufficient to increase fear. Finally, virus-mediated overexpression of a GH receptor antagonist was sufficient to block the fear enhancing effects of repeated ghrelin receptor stimulation. Thus, ghrelin requires GH in the amygdala to exert fear-enhancing effects. These results suggest that ghrelin mediates a novel branch of the stress response and highlight a previously unrecognized role for ghrelin
Historical changes in the major fish resources of the Great Lakes

USGS Publications Warehouse

Hartman, Wilbur L.; Evans, Marlene S.

1988-01-01

My purpose here is to review historic changes in the major fish resources of the five Great Lakes, and to identify the cause or causes for those changes. In some instances it will be clear that intensive fishing was the primary cause of change; in other instances it will be nearly as clear that predation by the sea lamprey played a significant if not dominant role in change; and in still others it will be clear (or at least circumstantial) that exotic species other than the sea lamprey have been implicated. The exotics that have invaded or been accidentally or purposefully released into the Great Lakes system have not only adversely affected indigenous fishes, but some have developed into new and valuable resources. However, when it comes to degradation of water quality and of critical habitat, the linkages to changes in fish populations are neither clear-cut nor quantifiable — their impacts were generally far more subtle and difficult to detect, but not necessarily of less importance. Inasmuch as a comprehensive review of all changes in fishery resources, water quality, and habitat conditions in the Great Lakes would be encyclopedic, I confine discussion here to prime examples related to the most historically important fish resources. One of the values of the approach used in this manuscript is the collation in a single-source document of the conclusions reached by many scientists on reasons for changes in the fish resources across the Great Lakes basin.
Supernova Remnant Science with AXIS

NASA Astrophysics Data System (ADS)

Williams, Brian J.; Yamaguchi, Hiroya; AXIS Science Team

2018-01-01

We present an overview of the supernova remnant (SNR) science that will be achieved with the Advanced X-ray Imaging Satellite (AXIS). AXIS follows in the footsteps of the spectacularly successful Chandra X-ray Observatory with similar or higher angular resolution and an order of magnitude more collecting area in the 0.3-10 keV band. These capabilities enable major advances in several areas of SNR science. These include, but are not limited to: 1) a more thorough spatial mapping of the ejecta products of both intermediate-mass and iron-group elements in core-collapse and Type Ia SNRs, particularly in remnants with a small diameter. The iron-group elements, specifically Cr, Mn, and Ni, are extremely important for constraining the explosion mechanism for SNe, but are generally weak and difficult to detect with Chandra, XMM-Newton, and Suzaku. 2) Studying the interface of a shock wave with the ambient ISM/CSM to constrain the degree of particle heating and acceleration at shock fronts. Chandra has only provided upper limits on shock precursor emission, and a detailed study of the thermal and nonthermal emission at the shock with greatly increased photon count rates will constrain the properties of the immediate post-shock plasma. 3) A high spatial resolution X-ray observatory will continue to build on the legacy begun by Chandra of studying the proper motion of young remnants. Directly measuring the dynamics of an SNR's evolution is crucial for understanding the explosion mechanism, and with the order of magnitude increase collecting area, we can measure the expansion of individual elemental species in the ejecta. 4) We will greatly increase the statistics of SNRs in nearby galaxies, going much faster and deeper than Chandra's observations. The increased depth of coverage would allow us to do spectroscopy in places where it was previously possible only to do rudimentary statistics. We can compare the local SNR population with the local star-formation rates for galaxies
State of the art in protection of erosion-corrosion on vertical axis tidal current turbine

NASA Astrophysics Data System (ADS)

Musabikha, Siti; Utama, I. Ketut Aria Pria; Mukhtasor

2018-05-01

Vertical axis tidal current turbine is main part of ocean energy devices which converts the tidal current energy into electricity. Its development is arising too due to increased interest research topic concerning climate change mitigation. Due to its rotating movement, it will be induced mechanical forces, such as shear stress and/or particle impact. Because of its natural operations, vertical axis turbine is also being exposed to harsh and corroding marine environment itself. In order to secure the vertical tidal turbine devices from mechanical wear and corrosion effects which is lead to a material loss, an appropriate erosion-corrosion protection needs to be defined. Its protection actionscan be derived such as design factors, material selections, inhibitors usage, cathodic protections, and coatings. This paper aims to analyze protection method which is necessary to control erosion-corrosion phenomenon that appears to the vertical axis tidal current turbine.
Design and optimize of 3-axis filament winding machine

NASA Astrophysics Data System (ADS)

Quanjin, Ma; Rejab, M. R. M.; Idris, M. S.; Bachtiar, B.; Siregar, J. P.; Harith, M. N.

2017-10-01

Filament winding technique is developed as the primary process for composite cylindrical structures fabrication at low cost. Fibres are wound on a rotating mandrel by a filament winding machine where resin impregnated fibres pass through a pay-out eye. This paper aims to develop and optimize a 3-axis, lightweight, practical, efficient, portable filament winding machine to satisfy the customer demand, which can fabricate pipes and round shape cylinders with resins. There are 3 main units on the 3-axis filament winding machine, which are the rotary unit, the delivery unit and control system unit. Comparison with previous existing filament winding machines in the factory, it has 3 degrees of freedom and can fabricate more complex shape specimens based on the mandrel shape and particular control system. The machine has been designed and fabricated on 3 axes movements with control system. The x-axis is for movement of the carriage, the y-axis is the rotation of mandrel and the z-axis is the movement of the pay-out eye. Cylindrical specimens with different dimensions and winding angles were produced. 3-axis automated filament winding machine has been successfully designed with simple control system.
Demographics and practices of semi-intensive free-range farming systems in Australia with an outdoor stocking density of ≤1500 hens/hectare

PubMed Central

Ruhnke, Isabelle; de Koning, Carolyn; Drake, Kelly; Skerman, Alan G.; Hinch, Geoff N.; Glatz, Philip C.

2017-01-01

Baseline information on demographics and practices on semi-intensive free-range egg farms with an outdoor stocking density of ≤1500 hens/hectare in Australia is presented. Free-range egg production is changing the structure of the egg industry in Australia and a broad variety and tiers of free-range systems have emerged due to lack of concrete legislative standards on outdoor stocking densities in the past. Information was extracted from a pre-existing online free-range poultry survey dataset, consisting of a total of 79 questions related to nutrition, pasture management, welfare and health, animal housing, environmental impact and economics. Forty-one free-range egg farms, with an outdoor stocking density of ≤1500 hens/hectare, were identified in the dataset from all major Australian states. Two types of semi-intensive free-range housing systems were documented: mobile (modified caravan/trailer) housing (56%), and fixed sheds (44%). Seventy-two percent of respondents reported >75% of the hens in the flock used the outdoor range. All respondents reported ingestion of range components by hens in the form of vegetation, insects, stones and grit. Up to 10% mortality was reported by 40% respondents with predation (34%), cannibalism (29%), heat stress (24%) and grass impaction (19.5%) as major causes. Biosecurity on farms was sub-optimal with 8 of the 10 actions implemented by <50% respondents. Customer demand, consumer sentiment and welfare were the major factors for farmers moving into free-range egg production. This study resulted in identification of current practices and key challenges on semi-intensive free-range egg farms. Applied research and communication of results to farmers is highly recommended to ensure optimum health and welfare of free-range laying hens and sustained egg production. PMID:29065169
Demographics and practices of semi-intensive free-range farming systems in Australia with an outdoor stocking density of ≤1500 hens/hectare.

PubMed

Singh, Mini; Ruhnke, Isabelle; de Koning, Carolyn; Drake, Kelly; Skerman, Alan G; Hinch, Geoff N; Glatz, Philip C

2017-01-01

Baseline information on demographics and practices on semi-intensive free-range egg farms with an outdoor stocking density of ≤1500 hens/hectare in Australia is presented. Free-range egg production is changing the structure of the egg industry in Australia and a broad variety and tiers of free-range systems have emerged due to lack of concrete legislative standards on outdoor stocking densities in the past. Information was extracted from a pre-existing online free-range poultry survey dataset, consisting of a total of 79 questions related to nutrition, pasture management, welfare and health, animal housing, environmental impact and economics. Forty-one free-range egg farms, with an outdoor stocking density of ≤1500 hens/hectare, were identified in the dataset from all major Australian states. Two types of semi-intensive free-range housing systems were documented: mobile (modified caravan/trailer) housing (56%), and fixed sheds (44%). Seventy-two percent of respondents reported >75% of the hens in the flock used the outdoor range. All respondents reported ingestion of range components by hens in the form of vegetation, insects, stones and grit. Up to 10% mortality was reported by 40% respondents with predation (34%), cannibalism (29%), heat stress (24%) and grass impaction (19.5%) as major causes. Biosecurity on farms was sub-optimal with 8 of the 10 actions implemented by <50% respondents. Customer demand, consumer sentiment and welfare were the major factors for farmers moving into free-range egg production. This study resulted in identification of current practices and key challenges on semi-intensive free-range egg farms. Applied research and communication of results to farmers is highly recommended to ensure optimum health and welfare of free-range laying hens and sustained egg production.
The rotation axis for stationary and axisymmetric space-times

NASA Astrophysics Data System (ADS)

van den Bergh, N.; Wils, P.

1985-03-01

A set of 'extended' regularity conditions is discussed which have to be satisfied on the rotation axis if the latter is assumed to be also an axis of symmetry. For a wide class of energy-momentum tensors these conditions can only hold at the origin of the Weyl canonical coordinate. For static and cylindrically symmetric space-times the conditions can be derived from the regularity of the Riemann tetrad coefficients on the axis. For stationary space-times, however, the extended conditions do not necessarily hold, even when 'elementary flatness' is satisfied and when there are no curvature singularities on the axis. The result by Davies and Caplan (1971) for cylindrically symmetric stationary Einstein-Maxwell fields is generalized by proving that only Minkowski space-time and a particular magnetostatic solution possess a regular axis of rotation. Further, several sets of solutions for neutral and charged, rigidly and differentially rotating dust are discussed.
Method for spinning up a three-axis controlled spacecraft

NASA Technical Reports Server (NTRS)

Vorlicek, Preston L. (Inventor)

1988-01-01

A three-axis controlled spacecraft (1), typically a satellite, is spun up about its roll axis (20) prior to firing a motor (2), i.e., a perigee kick motor, to achieve the requisite degree of angular momentum stiffness. Thrusters (21) for imparting rotation about the roll axis (20) are activated in open-loop fashion, typically at less than full duty cycle. Cross-axis torques induced by this rotational motion are compensated for by means of closed control loops for each of the pitch and yaw axes (30, 40, respectively). Each closed control loop combines a prebias torque (72) with torques (75, 74) representative of position and rate feedback information, respectively. A deadband (52) within each closed control loop can be widened during the spinup, to conserve fuel. Position feedback information (75) in each of the control loops is disabled upon saturation of the gyroscope associated with the roll axis (20).
Shot H3837: Darht's First Dual-Axis Explosive Experiment

NASA Astrophysics Data System (ADS)

Mendez, Jacob; McNeil, Wendy Vogan; Harsh, James; Hull, Lawrence

2011-06-01

Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic HydroTest (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II. Since the days of the Manhattan Project, penetrating radiography with multiple frames from different viewing angles has remained a high-profile goal at the Laboratory. H3837 is merely the beginning of a bright future for two-axis penetrating radiography.
Laser interferometric system for six-axis motion measurement.

PubMed

Zhang, Zhipeng; Menq, Chia-Hsiang

2007-08-01

This article presents the development of a precision laser interferometric system, which is designed to achieve six-axis motion measurement for real-time applications. By combining the advantage of the interferometer with a retroreflector and that of the interferometer with a plane mirror reflector, the system is capable of simultaneously measuring large transverse motions along and large rotational motions about three orthogonal axes. Based on optical path analysis along with the designed kinematics of the system, a closed form relationship between the six-axis motion parameters of the object being measured and the readings of the six laser interferometers is established. It can be employed as a real-time motion sensor for various six-axis motion control stages. A prototype is implemented and integrated with a six-axis magnetic levitation stage to illustrate its resolution and measurement range.
Shot H3837: Darht's first dual-axis explosive experiment

NASA Astrophysics Data System (ADS)

Harsh, James F.; Hull, Lawrence; Mendez, Jacob; McNeil, Wendy Vogan

2012-03-01

Test H3837 was the first explosive shot performed in front of both flash x-ray axes at the Los Alamos Dual Axis Radiographic Hydrodynamic Test (DARHT) facility. Executed in November 2009, the shot was an explosively-driven metal flyer plate in a series of experiments designed to explore equation-of-state properties of shocked materials. Imaging the initial shock wave traveling through the flyer plate, DARHT Axis II captured the range of motion from the shock front emergence in the flyer to breakout at the free surface; the Axis I pulse provided a perpendicular perspective of the shot at a time coinciding with the third pulse of Axis II.
A new technique for quantifying symmetry and opening angles in quartz c-axis pole figures: Implications for interpreting the kinematic and thermal properties of rocks

NASA Astrophysics Data System (ADS)

Hunter, N. J. R.; Weinberg, R. F.; Wilson, C. J. L.; Law, R. D.

2018-07-01

Variations in flow kinematics influence the type of crystallographic preferred orientations (CPOs) in plastically deformed quartz, yet we currently lack a robust means of quantifying the diagnostic symmetries that develop in the c-axis (0001) pole figure. In this contribution, we demonstrate how the symmetry of common c-axis topologies may be quantified by analysing the intensity distribution across a line transect of the pole figure margin. A symmetry value (S) measures the relative difference in intensities between marginal girdle maxima in the pole figure, and thus the degree to which the pole figure defines orthorhombic or monoclinic end member symmetries. This provides a semi-quantitative depiction of whether the rocks underwent coaxial or non-coaxial flow, respectively, and may subsequently be used to quantify other topological properties, such as the opening angle of girdle maxima. The open source Matlab® toolbox MTEX is used to quantify pole figure symmetries in quartzite samples from the Main Central Thrust (NW Himalaya) and the Moine Thrust (NW Scotland).
Goldstone radar evidence for short-axis mode non-principal-axis rotation of near-Earth asteroid (214869) 2007 PA8

NASA Astrophysics Data System (ADS)

Brozović, Marina; Benner, Lance A. M.; Magri, Christopher; Scheeres, Daniel J.; Busch, Michael W.; Giorgini, Jon D.; Nolan, Michael C.; Jao, Joseph S.; Lee, Clement G.; Snedeker, Lawrence G.; Silva, Marc A.; Lawrence, Kenneth J.; Slade, Martin A.; Hicks, Michael D.; Howell, Ellen S.; Taylor, Patrick A.; Sanchez, Juan A.; Reddy, Vishnu; Dykhuis, Melissa; Le Corre, Lucille

2017-04-01

We report radar and optical photometric observations of near-Earth asteroid (214869) 2007 PA8 obtained during October 2-November 13, 2012. We observed 2007 PA8 on sixteen days with Goldstone (8560 MHz, 3.5 cm) and on five days with the 0.6 m telescope at Table Mountain Observatory. Closest approach was on November 5 at a distance of 0.043 au. Images obtained with Goldstone's new chirp system achieved range resolutions as fine as 3.75 m, placing thousands of pixels on the asteroid's surface, and revealing that 2007 PA8 is an elongated, asymmetric object. Surface features include angularities, facets, and a concavity approximately 400 m in diameter. We used the Shape software to estimate the asteroid's 3D shape and spin state. 2007 PA8 has a broad, rounded end and a tapered, angular end with sharp-crested ridges. The asteroid's effective diameter is 1.35 ± 0.07 km, which in combination with the absolute magnitude of 16.30 ± 0.52 gives an optical albedo of pV = 0.29 ± 0.14. The shape modeling of the radar data revealed that 2007 PA8 is a non-principal axis (NPA) rotator in the short-axis mode with an average period of precession by the long axis around the angular momentum vector of 4.26 ± 0.02 days and an oscillatory period around the long axis of 20.55 ± 3.75 days. The amplitude of rolling around the long axis is 42 ± 7° . The angular momentum vector points toward ecliptic longitude and latitude of 273.6 ± 10°, +16.9 ± 5°. 2007 PA8 is only the second confirmed short-axis mode NPA rotator known in the near-Earth asteroid population after (99942) Apophis (Pravec et al., 2014). 2007 PA8 has a geopotential high at the equator, where the equator is defined as the plane that contains the long and intermediate axis. This geopotential extreme could be interpreted as a large, hidden surface depression, or as evidence that 2007 PA8 is a multi-component body.
Leading Schools through Major Change

ERIC Educational Resources Information Center

Syed, Sarosh

2013-01-01

Changing even the smallest things in schools is hard--just ask any principal who has overseen a rescheduling of bus routes. So imagine the difficulty of getting a school to move its curriculum and instruction from familiar learning requirements to brand-new nationwide standards. Yet this is exactly the sort of change public schools in 45 states…
Monte Carlo Simulation of Markov, Semi-Markov, and Generalized Semi- Markov Processes in Probabilistic Risk Assessment

NASA Technical Reports Server (NTRS)

English, Thomas

2005-01-01

A standard tool of reliability analysis used at NASA-JSC is the event tree. An event tree is simply a probability tree, with the probabilities determining the next step through the tree specified at each node. The nodal probabilities are determined by a reliability study of the physical system at work for a particular node. The reliability study performed at a node is typically referred to as a fault tree analysis, with the potential of a fault tree existing.for each node on the event tree. When examining an event tree it is obvious why the event tree/fault tree approach has been adopted. Typical event trees are quite complex in nature, and the event tree/fault tree approach provides a systematic and organized approach to reliability analysis. The purpose of this study was two fold. Firstly, we wanted to explore the possibility that a semi-Markov process can create dependencies between sojourn times (the times it takes to transition from one state to the next) that can decrease the uncertainty when estimating time to failures. Using a generalized semi-Markov model, we studied a four element reliability model and were able to demonstrate such sojourn time dependencies. Secondly, we wanted to study the use of semi-Markov processes to introduce a time variable into the event tree diagrams that are commonly developed in PRA (Probabilistic Risk Assessment) analyses. Event tree end states which change with time are more representative of failure scenarios than are the usual static probability-derived end states.
Vitamin D Axis in Inflammatory Bowel Diseases: Role, Current Uses and Future Perspectives

PubMed Central

Del Pinto, Rita; Ferri, Claudio; Cominelli, Fabio

2017-01-01

Increasing evidence supports the concept that the vitamin D axis possesses immunoregulatory functions, with vitamin D receptor (VDR) status representing the major determinant of vitamin D’s pleiotropic effects. Vitamin D promotes the production of anti-microbial peptides, including β-defensins and cathelicidins, the shift towards Th2 immune responses, and regulates autophagy and epithelial barrier integrity. Impairment of vitamin D-mediated pathways are associated with chronic inflammatory conditions, including inflammatory bowel diseases (IBD). Interestingly, inhibition of vitamin D pathways results in dysbiosis of the gut microbiome, which has mechanistically been implicated in the development of IBD. Herein, we explore the role of the vitamin D axis in immune-mediated diseases, with particular emphasis on its interplay with the gut microbiome in the pathogenesis of IBD. The potential clinical implications and therapeutic relevance of this interaction will also be discussed, including optimizing VDR function, both with vitamin D analogues and probiotics, which may represent a complementary approach to current IBD treatments. PMID:29112157
Dynamical study of low Earth orbit debris collision avoidance using ground based laser

NASA Astrophysics Data System (ADS)

Khalifa, N. S.

2015-06-01

The objective of this paper was to investigate the orbital velocity changes due to the effect of ground based laser force. The resulting perturbations of semi-major axis, miss distance and collision probability of two approaching objects are studied. The analytical model is applied for low Earth orbit debris of different eccentricities and area to mass ratio and the numerical test shows that laser of medium power ∼5 kW can perform a small change Δ V ‾ of an average magnitude of 0.2 cm/s which can be accumulated over time to be about 3 cm/day. Moreover, it is confirmed that applying laser Δ V ‾ results in decreasing collision probability and increasing miss distance in order to avoid collision.
Cam-Operated Pitch-Change Apparatus

NASA Technical Reports Server (NTRS)

Barnes, P. E. (Inventor)

1978-01-01

A pitch-change apparatus for a ducted thrust fan having a plurality of variable pitch blades employs a camming ring mounted coaxially at the hub at an axially fixed station along the hub axis for rotation about the hub axis both with the blades and relative to the blades. The ring has a generally spherical outer periphery and a plurality of helical camming grooves extending in a generally spherical plane on the periphery. Each of the variable pitch blades is connected to a pitch-change horn having a cam follower mounted on its outer end, and the camming ring and the horns are so arranged about the hub axis that the plurality of followers on the horns engage respectively the plurality of helical camming grooves. Rotary drive means rotates the camming ring relative to the blades to cause blade pitch to be changed through the cooperative operation of the camming grooves on the ring and the cam followers on the pitch-change horns.
Three-Axis Ground Reaction Force Distribution during Straight Walking.

PubMed

Hori, Masataka; Nakai, Akihito; Shimoyama, Isao

2017-10-24

We measured the three-axis ground reaction force (GRF) distribution during straight walking. Small three-axis force sensors composed of rubber and sensor chips were fabricated and calibrated. After sensor calibration, 16 force sensors were attached to the left shoe. The three-axis force distribution during straight walking was measured, and the local features of the three-axis force under the sole of the shoe were analyzed. The heel area played a role in receiving the braking force, the base area of the fourth and fifth toes applied little vertical or shear force, the base area of the second and third toes generated a portion of the propulsive force and received a large vertical force, and the base area of the big toe helped move the body's center of mass to the other foot. The results demonstrate that measuring the three-axis GRF distribution is useful for a detailed analysis of bipedal locomotion.

Three-axis force actuator for a magnetic bearing

NASA Technical Reports Server (NTRS)

Gondhalekar, Vijay (Inventor)

1998-01-01

This invention features a three-axis force actuator that axially, radially and rotatably supports a bearing member for frictionless rotation about an axis of rotation generally coincident with a Z-axis. Also featured is a magnetic bearing having such an actuator. The actuator includes an inner member, a magnetic member and a pole assembly having a ring member and four pole extending therefrom. The poles are equi-angular spaced from each other and radially spaced about the Z-axis. The inner member extends along the Z-axis and is a highly magnetic permeable material. The magnetic member is formed about the inner member outer surface, extends along the Z-axis and is configured so one magnetic pole polarity is located at its outer surface and the other polarity pole is located at its inner surface. Preferably, the magnetic member is a radially magnetized permanent magnet. The inner surface of the ring member is magnetically coupled to the magnetic member and a face of each pole is coupled to the bearing member. The magnetic member, the pole assembly, the inner member and the bearing member cooperate to generate a magnetic field that radially and rotatably supports a rotating member secured to the bearing member. The actuator further includes a plurality of electromagnetic coils. Preferably, a coil is formed about each pole and at least 2 coils are formed about the inner member. When energized, the electromagnetic coils generate a modulated magnetic field that stabilizes the rotating member in the desired operational position.
Hormonal (Cortical-Gonadotropic Axis) and Physical Changes With Two Years Intense Exercise Training in Elite Young Soccer Players.

PubMed

Hammami, Mohamed Ali; Ben Abderrahman, Abderraouf; Hackney, Anthony C; Kebsi, Wiem; Owen, Adam L; Nebigh, Amar; Racil, Ghazi; Tabka, Zouhair; Zouhal, Hassane

2017-09-01

Hammami, MA, Ben Abderrahman, A, Hackney, AC, Kebsi, W, Owen, AL, Nebigh, A, Racil, G, Tabka, Z, and Zouhal, H. Hormonal (cortical-gonadotropic axis) and physical changes with two years intense exercise training in elite young soccer players. J Strength Cond Res 31(9): 2388-2397, 2017-The aim of this study was to investigate the effects of 2 soccer-training seasons on physical fitness and hormone concentrations in elite youth soccer players. Twenty male elite soccer players (SP, age 14.5 ± 0.4 years) and 20 male control subjects (CS, age 14.3 ± 0.3 years) participated in the study. Anthropometric measurements, aerobic (Yo-Yo Intermittent Recovery Test Level 1 [YYIRT1]) and anaerobic soccer relevant performances (jump and sprint tests), blood testosterone (T), cortisol (C), sex hormone binding globulin (SHBG), and T/C ratio were assessed 5 times (from T0 to T4) during 2 competitive seasons. Significant differences from basal values (Δ) of T, SHBG, and C between SP and CS were observed (p < 0.01). Additionally, T and T/C ratio changes were positively correlated with physical performance (p ≤ 0.05). In conclusion, as expected, higher T concentration and greater power performance were observed in the soccer players group compared with controls. Our findings also show that the T concentrations and power performance outcomes co-vary positively over the 2 soccer seasons in soccer players.
Navigation Accuracy Guidelines for Orbital Formation Flying

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Alfriend, Kyle T.

2004-01-01

Some simple guidelines based on the accuracy in determining a satellite formation s semi-major axis differences are useful in making preliminary assessments of the navigation accuracy needed to support such missions. These guidelines are valid for any elliptical orbit, regardless of eccentricity. Although maneuvers required for formation establishment, reconfiguration, and station-keeping require accurate prediction of the state estimate to the maneuver time, and hence are directly affected by errors in all the orbital elements, experience has shown that determination of orbit plane orientation and orbit shape to acceptable levels is less challenging than the determination of orbital period or semi-major axis. Furthermore, any differences among the member s semi-major axes are undesirable for a satellite formation, since it will lead to differential along-track drift due to period differences. Since inevitable navigation errors prevent these differences from ever being zero, one may use the guidelines this paper presents to determine how much drift will result from a given relative navigation accuracy, or conversely what navigation accuracy is required to limit drift to a given rate. Since the guidelines do not account for non-two-body perturbations, they may be viewed as useful preliminary design tools, rather than as the basis for mission navigation requirements, which should be based on detailed analysis of the mission configuration, including all relevant sources of uncertainty.
Navigation Accuracy Guidelines for Orbital Formation Flying Missions

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell; Alfriend, Kyle T.

2003-01-01

Some simple guidelines based on the accuracy in determining a satellite formation's semi-major axis differences are useful in making preliminary assessments of the navigation accuracy needed to support such missions. These guidelines are valid for any elliptical orbit, regardless of eccentricity. Although maneuvers required for formation establishment, reconfiguration, and station-keeping require accurate prediction of the state estimate to the maneuver we, and hence are directly affected by errors in all the orbital elements, experience has shown that determination of orbit plane orientation and orbit shape to acceptable levels is less challenging than the determination of orbital period or semi-major axis. Furthermore, any differences among the member s semi-major axes are undesirable for a satellite formation, since it will lead to differential along-track drift due to period differences. Since inevitable navigation errors prevent these differences from ever being zero, one may use the guidelines this paper presents to determine how much drift will result from a given relative navigation accuracy, or conversely what navigation accuracy is required to limit drift to a given rate. Since the guidelines do not account for non-two-body perturbations, they may be viewed as useful preliminary design tools, rather than as the basis for mission navigation requirements, which should be based on detailed analysis of the mission configuration, including all relevant sources of uncertainty.
Comparison of changes in the transverse dental axis between patients with skeletal Class III malocclusion and facial asymmetry treated by orthognathic surgery with and without presurgical orthodontic treatment.

PubMed

Song, Han-Sol; Choi, Sung-Hwan; Cha, Jung-Yul; Lee, Kee-Joon; Yu, Hyung-Seog

2017-07-01

To evaluate transverse skeletal and dental changes, including those in the buccolingual dental axis, between patients with skeletal Class III malocclusion and facial asymmetry after bilateral intraoral vertical ramus osteotomy with and without presurgical orthodontic treatment. This retrospective study included 29 patients with skeletal Class III malocclusion and facial asymmetry including menton deviation > 4 mm from the midsagittal plane. To evaluate changes in transverse skeletal and dental variables (i.e., buccolingual inclination of the upper and lower canines and first molars), the data for 16 patients who underwent conventional orthognathic surgery (CS) were compared with those for 13 patients who underwent preorthodontic orthognathic surgery (POGS), using three-dimensional computed tomography at initial examination, 1 month before surgery, and at 7 days and 1 year after surgery. The 1-year postsurgical examination revealed no significant changes in the postoperative transverse dental axis in the CS group. In the POGS group, the upper first molar inclined lingually on both sides (deviated side, -1.8° ± 2.8°, p = 0.044; nondeviated side, -3.7° ± 3.3°, p = 0.001) and the lower canine inclined lingually on the nondeviated side (4.0° ± 5.4°, p = 0.022) during postsurgical orthodontic treatment. There were no significant differences in the skeletal and dental variables between the two groups at 1 year after surgery. POGS may be a clinically acceptable alternative to CS as a treatment to achieve stable transverse axes of the dentition in both arches in patients with skeletal Class III malocclusion and facial asymmetry.
Interaction of brain noradrenergic system and the hypothalamic-pituitary-adrenal (HPA) axis in man.

PubMed

Young, Elizabeth A; Abelson, James L; Cameron, Oliver G

2005-09-01

Numerous interactions between the brainstem locus coeruleus system and the HPA axis have been shown in experimental animals. This relationship is less well characterized in humans and little is known about the influence of psychiatric disorders, which disturb one of these systems, on this relationship. Untreated subjects with pure MDD (n = 13), MDD with comorbid anxiety disorders (n = 17), and pure anxiety disorders (n = 15) were recruited by advertising. Age and sex matched control subjects were recruited for each subject with a psychiatric diagnosis (n = 45). All subjects underwent a social stressor, the Trier Social Stress Test (TSST), and blood was collected for ACTH assay. These same subjects also underwent a clonidine challenge study for assessment of growth hormone release as a marker of tonic noradrenergic activation. Examining log transformed area under the curve response for each hormone, a significant negative relationship (simple regression) was observed between systems in normal subjects. This relationship was preserved in anxiety subjects. However, both pure depressed and comorbid depressed and anxiety subjects demonstrated disruption of this relationship. Under normal circumstances, noradrenergic systems can influence the magnitude of the HPA axis response to stress. However, in subjects with major depression, HPA axis activation appears autonomous of noradrenergic influence.
Multifunctional semi-interpenetrating polymer network-nanoencapsulated cathode materials for high-performance lithium-ion batteries

PubMed Central

Kim, Ju-Myung; Park, Jang-Hoon; Lee, Chang Kee; Lee, Sang-Young

2014-01-01

As a promising power source to boost up advent of next-generation ubiquitous era, high-energy density lithium-ion batteries with reliable electrochemical properties are urgently requested. Development of the advanced lithium ion-batteries, however, is staggering with thorny problems of performance deterioration and safety failures. This formidable challenge is highly concerned with electrochemical/thermal instability at electrode material-liquid electrolyte interface, in addition to structural/chemical deficiency of major cell components. Herein, as a new concept of surface engineering to address the abovementioned interfacial issue, multifunctional conformal nanoencapsulating layer based on semi-interpenetrating polymer network (semi-IPN) is presented. This unusual semi-IPN nanoencapsulating layer is composed of thermally-cured polyimide (PI) and polyvinyl pyrrolidone (PVP) bearing Lewis basic site. Owing to the combined effects of morphological uniqueness and chemical functionality (scavenging hydrofluoric acid that poses as a critical threat to trigger unwanted side reactions), the PI/PVP semi-IPN nanoencapsulated-cathode materials enable significant improvement in electrochemical performance and thermal stability of lithium-ion batteries. PMID:24710575
Partitioning understory evapotranspiration in semi-arid ecosystems in Namibia using the isotopic composition of water vapour

NASA Astrophysics Data System (ADS)

de Blécourt, Marleen; Gaj, Marcel; Holtorf, Kim-Kirsten; Gröngröft, Alexander; Brokate, Ralph; Himmelsbach, Thomas; Eschenbach, Annette

2016-04-01

In dry environments with a sparse vegetation cover, understory evapotranspiration is a major component of the ecosystem water balance. Consequently, knowledge on the size of evapotranspiration fluxes and the driving factors is important for our understanding of the hydrological cycle. Understory evapotranspiration is made up of soil evaporation and plant transpiration. Soil evaporation can be measured directly from patches free of vegetation. However, when understory vegetation is present distinguishing between soil evaporation and plant transpiration is challenging. In this study, we aim to partition understory evapotranspiration based on an approach that combines the measurements of water-vapour fluxes using the closed chamber method with measurements of the isotopic composition of water vapour. The measurements were done in the framework of SASSCAL (Southern African Science Service Centre for Climate Change and Adaptive Land Management). The study sites were located in three different semi-arid ecosystems in Namibia: thornbush savanna, Baikiaea woodland and shrubland. At each site measurements were done under tree canopies as well as at unshaded areas between the canopies. We measured evaporation from the bare soil and evapotranspiration from patches covered with herbaceous species and shrubs using a transparent chamber connected with an infrared gas analyser (LI-8100A, LICOR Inc.). The stable isotope composition of water vapour inside the chamber and depth profiles of soil water stable isotopes were determined in-situ using a tuneable off-axis integrated cavity output spectroscope (OA-ICOS, Los Gatos Research, DLT 100). Xylem samples were extracted using the cryogenic vacuum extraction method and the isotopic composition of the extracted water was measured subsequently with a cavity-ring-down spectrometer (CRDS L2120-i, Picarro Inc.). We will present the quantified fluxes of understory evapotranspiration measured in the three different ecosystems, show the
4963 Kanroku: Asteroid with a possible precession of rotation axis

NASA Astrophysics Data System (ADS)

Sokova, Iraida A.; Marchini, Alessandro; Franco, Lorenzo; Papini, Riccardo; Salvaggio, Fabio; Palmas, Teodora; Sokov, Eugene N.; Garlitz, Joe; Knight, Carl R.; Bretton, Marc

2018-04-01

Based on photometric observations of 4963 Kanroku as part of a campaign to measure its light-curve, changes of the light-curve profile have been detected. These changes are of a periodic nature, i.e. the profiles change with a detected period P = 16.4032 h. Based on simulations of the shape of the asteroid and using observational data, we make the assumption that such changes of the light-curve of the asteroid could be caused by the existence of a precession force acting on the axis of rotation of the asteroid. Simulations of the 4963 Kanroku light-curve, taking into account the detected precession, and the parameters for the shape of the asteroid, the modeled light-curves are in good agreement with the light-curves obtained from the observation campaign. Thus, the detected precession force may indicate a possible satellite of the asteroid 4963 Kanroku.
Climate change mitigation by carbon stock - the case of semi-arid West Africa

NASA Astrophysics Data System (ADS)

Lykke, A. M.; Barfod, A. S.; Tinggaard Svendsen, G.; Greve, M.; Svenning, J.-C.

2009-11-01

Semi-arid West Africa has not been integrated into the afforestation/reforestation (AR) carbon market. Most projects implemented under the Clean Development Mechanism (CDM) have focused on carbon emission reductions from industry and energy consumption, whereas only few (only one in West Africa) have been certified for AR carbon sequestration. A proposed mechanism, Reducing Emissions from Deforestation and Degradation (REDD) to be discussed under COP15 aims to reduce emissions by conserving already existing forests. REDD has high potential for carbon stocking at low costs, but focuses primarily on rain forest countries and excludes semi-arid West Africa from the preliminary setup. African savannas have potential to store carbon in the present situation with degrading ecosystems and relatively low revenues from crops and cattle, especially if it is possible to combine carbon stocking with promotion of secondary crops such as food resources and traditional medicines harvested on a sustainable basis. Methods for modelling and mapping of potential carbon biomass are being developed, but are still in a preliminary state. Although economic benefits from the sale of carbon credits are likely to be limited, carbon stocking is an interesting option if additional benefits are considered such as improved food security and protection of biodiversity.
Multi-axis control based on movement control cards in NC systems

NASA Astrophysics Data System (ADS)

Jiang, Tingbiao; Wei, Yunquan

2005-12-01

Today most movement control cards need special control software of topper computers and are only suitable for fixed-axis controls. Consequently, the number of axes which can be controlled is limited. Advanced manufacture technology develops at a very high speed, and that development brings forth. New requirements for movement control in mechanisms and electronics. This paper introduces products of the 5th generation of movement control cards, PMAC 2A-PC/104, made by the Delta Tau Company in the USA. Based on an analysis of PMAC 2A-PC/104, this paper first describes two aspects relevant to the hardware structure of movement control cards and the interrelated software of the topper computers. Then, two methods are presented for solving these problems. The first method is to set limit switches on the movement control cards; all of them can be used to control each moving axis. The second method is to program applied software with existing programming language (for example, VC ++, Visual Basic, Delphi, and so forth). This program is much easier to operate and expand by its users. By using a limit switch, users can choose different axes in movement control cards. Also, users can change parts of the parameters in the control software of topper computers to realize different control axes. Combining these 2 methods proves to be convenient for realizing multi-axis control in numerical control systems.
GLOBAL CHANGE RESEARCH NEWS #10: MULTIAGENCY, MULTINATIONAL GLOBAL CHANGE RESEARCH EFFORT IN THE UPPER SAN PEDRO BASIN

EPA Science Inventory

This edition reports on a multiagency, multinational global-change research effort that seeks to evaluate the consequences of natural and human-induced changes in semi-arid environments. The Semi-Arid Land-Surface-Atmosphere Program ("SALSA") is focused on the environmentally sen...
Adipose tissue and the reproductive axis: biological aspects

USDA-ARS?s Scientific Manuscript database

The discovery of leptin clearly demonstrated a relationship between body fat and the neuroendocrine axis since leptin influences appetite and the reproductive axis. Since adipose tissue is a primary source of leptin, adipose tissue is no longer considered as simply a depot to store fat. Recent find...
Human semi-supervised learning.

PubMed

Gibson, Bryan R; Rogers, Timothy T; Zhu, Xiaojin

2013-01-01

Most empirical work in human categorization has studied learning in either fully supervised or fully unsupervised scenarios. Most real-world learning scenarios, however, are semi-supervised: Learners receive a great deal of unlabeled information from the world, coupled with occasional experiences in which items are directly labeled by a knowledgeable source. A large body of work in machine learning has investigated how learning can exploit both labeled and unlabeled data provided to a learner. Using equivalences between models found in human categorization and machine learning research, we explain how these semi-supervised techniques can be applied to human learning. A series of experiments are described which show that semi-supervised learning models prove useful for explaining human behavior when exposed to both labeled and unlabeled data. We then discuss some machine learning models that do not have familiar human categorization counterparts. Finally, we discuss some challenges yet to be addressed in the use of semi-supervised models for modeling human categorization. Copyright © 2013 Cognitive Science Society, Inc.
Stress-induced sensitization: the hypothalamic-pituitary-adrenal axis and beyond.

PubMed

Belda, Xavier; Fuentes, Silvia; Daviu, Nuria; Nadal, Roser; Armario, Antonio

2015-01-01

Exposure to certain acute and chronic stressors results in an immediate behavioral and physiological response to the situation followed by a period of days when cross-sensitization to further novel stressors is observed. Cross-sensitization affects to different behavioral and physiological systems, more particularly to the hypothalamus-pituitary-adrenal (HPA) axis. It appears that the nature of the initial (triggering) stressor plays a major role, HPA cross-sensitization being more widely observed with systemic or high-intensity emotional stressors. Less important appears to be the nature of the novel (challenging) stressor, although HPA cross-sensitization is better observed with short duration (5-15 min) challenging stressors. In some studies with acute immune stressors, HPA sensitization appears to develop over time (incubation), but most results indicate a strong initial sensitization that progressively declines over the days. Sensitization can affect other physiological system (i.e. plasma catecholamines, brain monoamines), but it is not a general phenomenon. When studied concurrently, behavioral sensitization appears to persist longer than that of the HPA axis, a finding of interest regarding long-term consequences of traumatic stress. In many cases, behavioral and physiological consequences of prior stress can only be observed following imposition of a new stressor, suggesting long-term latent effects of the initial exposure.
Combining Landsat and MODIS Data to Assess Trends in Bioproductivity in the Context of Land Use/Land Cover Change in Semi-arid West Africa

NASA Astrophysics Data System (ADS)

Herrmann, S. M.; Tappan, G. G.

2015-12-01

Semi-arid West Africa is experiencing change at many levels (climatic, agricultural, socioeconomic), which leaves an imprint on the land surface that can be characterized by a range of long term satellite observations. This research addresses the questions of (1) what dominant trajectories of land use/land cover (LULC) change have occurred in the region and (2) whether particular LULC trajectories are associated with significant positive or negative trends in bioproductivity. Two types of satellite data were used in complementary fashion: (1) Landsat multispectral data were visually interpreted using the traditional dot grid method, whereby the interpreter identifies and attributes LULC at point locations spaced 2km apart. Interpreted LULC maps were produced for three points in time (1975, 2000, 2013), and LULC change statistics extracted from them. (2) The MODIS Normalized Difference Vegetation Index (NDVI) was used as a proxy for bioproductivity and temporal trends of annual mean, maximum and minimum NDVI extracted at the sampling dots of known LULC for the period 2000-2013. The trends were analyzed with respect to the most prominent LULC classes and transitions, in particular from agriculture to natural vegetation and vice versa, and stratified by regions of similar mean annual precipitation. The most important LULC change over the almost 40-year period is a progressive expansion of agricultural lands, which has been responsible for major incursions into the region's remaining savannas and woodlands. To a lesser extent, abandonment of agriculture has given rise to long term fallow and eventually reversion to steppe or savanna. Another important change observed is the expansion of open steppe at the expense of savanna in the Sahel region. In terms of bioproductivity, while no significant trends in NDVI predominate overall, there are more instances of positive than of negative significant trends across the region. Contrary to our initial expectations, preliminary
[Kennedy V Axis assessment in an Italian outpatient and inpatient population].

PubMed

Mundo, Emanuela; Bonalume, Laura; Del Corno, Franco; Madeddu, Fabio; Lang, Margherita

2010-01-01

Kennedy Axis V or K Axis acts is an alternative tool to the DSM-IVTR Global Assessment of Functioning (GAF) Scale, that many researchers describe as a scale with poor inter-rater reliability and clinical utility. Unlike the GAF scale, K Axis provides a multidimensional and multiaxial approach to measure personal, social and interpersonal functioning in psychiatric outpatients and inpatients. In this study, we examined K Axis's inter-raters reliability by using it with an Italian clinical population. Clinicians used Kennedy Axis V to assess global functioning among 180 inpatients, in 9 psychiatric services in Lombardia and Piemonte. Patients were divided into 4 different diagnostic groups, according to the DSM-IV-TR criteria. Intraclass correlations between two independent raters's scores reveal high level of interrater reliability for all K Axis scales (0,633 < ICC < 0,813). Highly significant results in the Kruskal-Wallis test demonstrate that the patient diagnosis influence all the scales scores. Significant differences in patients functioning profiles in all K Axis scales, apart from Violence one, were noted between different diagnosis groups. In this study high level of raters agreement was noted, even if K Axis scales were used in different mental health services from different clinicians. K Axis scales provide a useful profile of patient global functioning, in line with the specific pathology.
Choices in higher education: Majoring in and changing from the sciences

NASA Astrophysics Data System (ADS)

Minear, Nancy Ann

This dissertation addresses patterns of retention of undergraduate science, engineering and mathematics (SEM) students, with special attention paid to female and under represented minority students. As such, the study is focused on issues related to academic discipline and institutional retention, rather than the retention of students in the overall system of higher education. While previous retention studies have little to say about rates of retention that are specific to the sciences (or any other specific area of study) or employ models that rely on students' performance at the college level, this work address both points by identifying the post secondary academic performance characteristics of persisters and non-persisters in the sciences by gender, ethnicity and matriculating major as well as identifying introductory SEM course requirements that prevent students from persisting in sciencegender, ethnicity and matriculating major as well as identifying introductory SEM course requirements that prevent students from persisting in science majors. A secondary goal of investigating the usefulness of institutional records for retention research is addressed. Models produced for the entire population and selected subpopulations consistently classified higher-performing (both SEM and non-SEM grade point averages) students into Bachelor of Science categories using the number of Introductory Chemistry courses attempted at the university. For lower performing students, those with more introductory chemistry courses were classified as changing majors out of the sciences, and in general as completing a Bachelor of Arts degree. Performance in gatekeeper courses as a predictor of terminal academic status was limited to Introductory Physics for a small number of cases. Performance in Introductory Calculus and Introductory Chemistry were not consistently utilized as predictor variables. The models produced for various subpopulations (women, ethnic groups and matriculation
Linking Climate to Incidence of Zoonotic Cutaneous Leishmaniasis (L. major) in Pre-Saharan North Africa

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

Bounoua, Lahouari; Kahime, Kholoud; Houti, Leila

Shifts in surface climate may have changed the dynamic of zoonotic cutaneous leishmaniasis (ZCL) in the pre-Saharan zones of North Africa. Caused by Leishmania major, this form multiplies in the body of rodents serving as reservoirs of the disease. The parasite is then transmitted to human hosts by the bite of a Phlebotomine sand fly (Diptera: Psychodidae) that was previously fed by biting an infected reservoir. We examine the seasonal and interannual dynamics of the incidence of this ZCL as a function of surface climate indicators in two regions covering a large area of the semi-arid Pre-Saharan North Africa. Resultsmore » suggest that in this area, changes in climate may have initiated a trophic cascade that resulted in an increase in ZCL incidence.« less
Chemical ageing and transformation of diffusivity in semi-solid multi-component organic aerosol particles

NASA Astrophysics Data System (ADS)

Pfrang, C.; Shiraiwa, M.; Pöschl, U.

2011-04-01

Recent experimental evidence underlines the importance of reduced diffusivity in amorphous semi-solid or glassy atmospheric aerosols. This paper investigates the impact of diffusivity on the ageing of multi-component reactive organic particles representative of atmospheric cooking aerosols. We apply and extend the recently developed KM-SUB model in a study of a 12-component mixture containing oleic and palmitoleic acids. We demonstrate that changes in the diffusivity may explain the evolution of chemical loss rates in ageing semi-solid particles, and we resolve surface and bulk processes under transient reaction conditions considering diffusivities altered by oligomerisation. This new model treatment allows prediction of the ageing of mixed organic multi-component aerosols over atmospherically relevant time scales and conditions. We illustrate the impact of changing diffusivity on the chemical half-life of reactive components in semi-solid particles, and we demonstrate how solidification and crust formation at the particle surface can affect the chemical transformation of organic aerosols.

Chemical ageing and transformation of diffusivity in semi-solid multi-component organic aerosol particles

NASA Astrophysics Data System (ADS)

Pfrang, C.; Shiraiwa, M.; Pöschl, U.

2011-07-01

Recent experimental evidence underlines the importance of reduced diffusivity in amorphous semi-solid or glassy atmospheric aerosols. This paper investigates the impact of diffusivity on the ageing of multi-component reactive organic particles approximating atmospheric cooking aerosols. We apply and extend the recently developed KM-SUB model in a study of a 12-component mixture containing oleic and palmitoleic acids. We demonstrate that changes in the diffusivity may explain the evolution of chemical loss rates in ageing semi-solid particles, and we resolve surface and bulk processes under transient reaction conditions considering diffusivities altered by oligomerisation. This new model treatment allows prediction of the ageing of mixed organic multi-component aerosols over atmospherically relevant timescales and conditions. We illustrate the impact of changing diffusivity on the chemical half-life of reactive components in semi-solid particles, and we demonstrate how solidification and crust formation at the particle surface can affect the chemical transformation of organic aerosols.
The effect of the Earth's oblateness on the Moon's physical libration in latitude

NASA Astrophysics Data System (ADS)

Kondratyev, B. P.

2013-05-01

The Moon's physical libration in latitude generated by gravitational forces caused by the Earth's oblateness has been examined by a vector analytical method. Libration oscillations are described by a close set of five linear inhomogeneous differential equations, the dispersion equation has five roots, one of which is zero. A complete solution is obtained. It is revealed that the Earth's oblateness: a) has little effect on the instantaneous axis of Moon's rotation, but causes an oscillatory rotation of the body of the Moon with an amplitude of 0.072″ and pulsation period of 16.88 Julian years; b) causes small nutations of poles of the orbit and of the ecliptic along tight spirals, which occupy a disk with a cut in a center and with radius of 0.072″. Perturbations caused by the spherical Earth generate: a) physical librations in latitude with an amplitude of 34.275″; b) nutational motion for centers of small spiral nutations of orbit (ecliptic) pole over ellipses with semi-major axes of 113.850″ (85.158″) and the first pole rotates round the second one along a circle with radius of 28.691″; c) nutation of the Moon's celestial pole over an ellipse with a semi-major axis of 45.04″ and with an axes ratio of about 0.004 with a period of T = 27.212 days. The principal ellipse's axis is directed tangentially with respect to the precession circumference, along which the celestial pole moves nonuniformly nearly in one dimension. In contrast to the accepted concept, the latitude does not change while the Moon's poles of rotation move. The dynamical reason for the inclination of the Moon's mean equator with respect to the ecliptic is oblateness of the body of the Moon.
Bayesian semi-parametric analysis of Poisson change-point regression models: application to policy making in Cali, Colombia.

PubMed

Park, Taeyoung; Krafty, Robert T; Sánchez, Alvaro I

2012-07-27

A Poisson regression model with an offset assumes a constant baseline rate after accounting for measured covariates, which may lead to biased estimates of coefficients in an inhomogeneous Poisson process. To correctly estimate the effect of time-dependent covariates, we propose a Poisson change-point regression model with an offset that allows a time-varying baseline rate. When the nonconstant pattern of a log baseline rate is modeled with a nonparametric step function, the resulting semi-parametric model involves a model component of varying dimension and thus requires a sophisticated varying-dimensional inference to obtain correct estimates of model parameters of fixed dimension. To fit the proposed varying-dimensional model, we devise a state-of-the-art MCMC-type algorithm based on partial collapse. The proposed model and methods are used to investigate an association between daily homicide rates in Cali, Colombia and policies that restrict the hours during which the legal sale of alcoholic beverages is permitted. While simultaneously identifying the latent changes in the baseline homicide rate which correspond to the incidence of sociopolitical events, we explore the effect of policies governing the sale of alcohol on homicide rates and seek a policy that balances the economic and cultural dependencies on alcohol sales to the health of the public.
Unsteady loading of a vertical-axis turbine in the interaction with an upstream deflector

NASA Astrophysics Data System (ADS)

Kim, Daegyoum; Gharib, Morteza

2014-01-01

Torque generation and flow distribution of a lift-based vertical-axis turbine with an upstream deflecting plate are investigated in water tunnel experiments. The deployment of a deflector in front of a lift-based turbine is a promising approach to increase local flow velocity and enhance energy conversion efficiency without consideration for complicated control. For the turbine with the deflector, the phase during which the blade passes near the front end of the turbine has a major contribution to torque increase from the case without the deflector. Meanwhile, the deflector can have a negative effect in torque generation at the phase when the blade moves upstream against free stream if the turbine is placed close to the deflector in a crosswise direction. The change of nearby flow distribution by the deflector is also examined to find its correlation with torque generation. When the blade rotates through the near-wake region of the deflector, the blade can collides with the vortical structure shed from the deflector. This interaction causes significant torque fluctuation.
Description of the three axis low-g accelerometer package

NASA Technical Reports Server (NTRS)

Amalavage, A. J.; Fikes, E. H.; Berry, E. H.

1978-01-01

The three axis low-g accelerometer package designed for use on the Space Processing Application Rocket (SPAR) Program is described. The package consists of the following major sections: (1) three Kearfott model 2412 accelerometers mounted in an orthogonal triad configuration on a temperature controlled, thermally isolated cube, (2) the accelerometer servoelectronics (printed circuit cards PC-6 through PC-12), and (3) the signal conditioner (printed circuit cards PC-15 and PC-16). The measurement range is 0 + or - 0.031 g with a quantization of 1.1 x 10 to the 7th power g. The package was flown successfully on six SPAR launches with the Black Brant booster. These flights provide approximately 300 s of free fall or zero-g environment.
Major episodes of geologic change - Correlations, time structure and possible causes

NASA Technical Reports Server (NTRS)

Rampino, Michael R.; Caldeira, Ken

1993-01-01

Published data sets of major geologic events of the past about 250 Myr (extinction events, sea-level lows, continental flood-basalt eruptions, mountain-building events, abrupt changes in sea-floor spreading, ocean-anoxic and blackshale events and the largest evaporite deposits) have been synthesized (with estimated errors). These events show evidence for a statistically significant periodic component with an underlying periodicity, formally equal to 26.6 Myr, and a recent maximum, close to the present time. The cycle may not be strictly periodic, but a periodicity of about 30 Myr is robust to probable errors in dating of the geologic events. The intervals of geologic change seem to involve jumps in sea-floor spreading associated with episodic continental rifting, volcanism, enhanced orogeny, global sea-level changes and fluctuations in climate. The period may represent a purely internal earth-pulsation, but evidence of planetesimal impacts at several extinction boundaries, and a possible underlying cycle of 28-36 Myr in crater ages, suggests that highly energetic impacts may be affecting global tectonics. A cyclic increase in the flux of planetesimals might result from the passage of the Solar System through the central plane of the Milky Way Galaxy - an event with a periodicity and mean phasing similar to that detected in the geologic changes.
A framework for understanding semi-permeable barrier effects on migratory ungulates

USGS Publications Warehouse

Sawyer, Hall; Kauffman, Matthew J.; Middleton, Arthur D.; Morrison, Thomas A.; Nielson, Ryan M.; Wyckoff, Teal B.

2013-01-01

1. Impermeable barriers to migration can greatly constrain the set of possible routes and ranges used by migrating animals. For ungulates, however, many forms of development are semi-permeable, and making informed management decisions about their potential impacts to the persistence of migration routes is difficult because our knowledge of how semi-permeable barriers affect migratory behaviour and function is limited. 2. Here, we propose a general framework to advance the understanding of barrier effects on ungulate migration by emphasizing the need to (i) quantify potential barriers in terms that allow behavioural thresholds to be considered, (ii) identify and measure behavioural responses to semi-permeable barriers and (iii) consider the functional attributes of the migratory landscape (e.g. stopovers) and how the benefits of migration might be reduced by behavioural changes. 3. We used global position system (GPS) data collected from two subpopulations of mule deer Odocoileus hemionus to evaluate how different levels of gas development influenced migratory behaviour, including movement rates and stopover use at the individual level, and intensity of use and width of migration route at the population level. We then characterized the functional landscape of migration routes as either stopover habitat or movement corridors and examined how the observed behavioural changes affected the functionality of the migration route in terms of stopover use. 4. We found migratory behaviour to vary with development intensity. Our results suggest that mule deer can migrate through moderate levels of development without any noticeable effects on migratory behaviour. However, in areas with more intensive development, animals often detoured from established routes, increased their rate of movement and reduced stopover use, while the overall use and width of migration routes decreased. 5. Synthesis and applications. In contrast to impermeable barriers that impede animal movement
Effect of viewing distance and location of the axis of head rotation on the monkey's vestibuloocular reflex. I. Eye movement responses.

PubMed

Snyder, L H; King, W M

1992-04-01

1. The vestibuloocular reflex (VOR) stabilizes images on the retina against movements of the head in space. Viewing distance, target eccentricity, and location of the axis of rotation may influence VOR responses because rotation of the head about most axes in space rotates and translates the eyes relative to visual targets. To study the VOR response to combined rotation and translation, monkeys were placed on a rate table and rotated briefly in the dark about a vertical axis that was located in front of or behind the eyes. The monkeys fixated a near or far visual target that was extinguished before the rotation. Eye movements were recorded from both eyes by the use of the search coil technique. 2. Peak eye velocity evoked by the VOR was linearly related to vergence angle for any axis of rotation. The percent change in the VOR with near target viewing relative to far target viewing at a vergence angle of 20 degrees was linearly related to the location of the axis of rotation. Axes located behind the eyes produced positive changes in VOR amplitude, and axes located in front of the eyes produced negative changes in VOR amplitude. An axis of rotation located in the coronal plane containing the centers of rotation of the eyes produced no modification of VOR amplitude. For any axis, the VOR compensated for approximately 90% of the translation of the eye relative to near targets. 3. The initial VOR response was not correct in magnitude but was refined by a series of three temporally delayed corrections of increasing complexity. The earliest VOR-evoked eye movement (10-20 ms after rotation onset) was independent of viewing distance and rotational axis location. In the next 100 ms, eye speed appeared to be sequentially modified three times: within 20 ms by viewing distance; within 30 ms by otolith translation; and within 100 ms by eye translation relative to the visual target. 4. These data suggest a formal model of the VOR consisting of four channels. Channel 1 conveys an
Influence of ethynylestradiol and methyltestosterone on the hypothalamo-hypophyseal-gonadal axis of adult air-breathing catfish, Clarias gariepinus.

PubMed

Swapna, I; Senthilkumaran, B

2009-11-27

Adult male and female air-breathing catfish Clarias gariepinus were treated with ethynylestradiol (EE(2)) and methyltestosterone (MT) at concentrations of 1microg/L, respectively for 21 days. EE(2) treatment caused disappearance of spermatids/sperm from several testicular lumen/lobules in males while MT treatment to females led to precocious ovarian development. EE(2) caused significant fluid retention in all tissues including peritoneal cavity and seminal vesicles. Immunocytochemical localization of catfish GnRH (cfGnRH) and luteinizing hormone (LH) in preoptic area-hypothalamus (POA-H) and pituitary, respectively, revealed decreased immunoreactivity (ir-) following EE(2) treatment in males. MT treatment however caused no observable change in cfGnRH ir- and a significant increase in LH ir- in females. Semi-quantitative RT-PCR analysis indicated that cfGnRH transcripts in POA-H decreased significantly following EE(2) and MT treatment in males and females, respectively. Levels of POA-H dopamine (inhibitory monoamine for gonadotropin [GTH] synthesis and release) increased following EE(2) and MT treatment in males and females while levels of serotonin and norepinephrine (GTH-stimulatory monoamines) decreased significantly. The results demonstrate a direct in vivo effect of sex steroid analogs on cfGnRH-LH axis and monoaminergic system vis-à-vis on gonads in addition to probable direct action on gonads.
Land Use/land Cover Changes in Semi-Arid Mountain Landscape in Southern India: a Geoinformatics Based Markov Chain Approach

NASA Astrophysics Data System (ADS)

Rahaman, S. A.; Aruchamy, S.; Balasubramani, K.; Jegankumar, R.

2017-05-01

Nowadays land use/ land cover in mountain landscape is in critical condition; it leads to high risky and uncertain environments. These areas are facing multiple stresses including degradation of land resources; vagaries of climate and depletion of water resources continuously affect land use practices and livelihoods. To understand the Land use/Land cover (Lu/Lc) changes in a semi-arid mountain landscape, Kallar watershed of Bhavani basin, in southern India has been chosen. Most of the hilly part in the study area covers with forest, plantation, orchards and vegetables and which are highly affected by severe soil erosion, landslide, frequent rainfall failures and associated drought. The foothill regions are mainly utilized for agriculture practices; due to water scarcity and meagre income, the productive agriculture lands are converted into settlement plots and wasteland. Hence, land use/land cover change deduction; a stochastic processed based method is indispensable for future prediction. For identification of land use/land cover, and vegetation changes, Landsat TM, ETM (1995, 2005) and IRS P6- LISS IV (2015) images were used. Through CAMarkov chain analysis, Lu/Lc changes in past three decades (1995, 2005, and 2015) were identified and projected for (2020 and 2025); Normalized Difference Vegetation Index (NDVI) were used to find the vegetation changes. The result shows that, maximum changes occur in the plantation and slight changes found in forest cover in the hilly terrain. In foothill areas, agriculture lands were decreased while wastelands and settlement plots were increased. The outcome of the results helps to farmer and policy makers to draw optimal lands use planning and better management strategies for sustainable development of natural resources.
AXIS - Advanced X-ray Imaging Sarellite

NASA Astrophysics Data System (ADS)

Loewenstein, Michael; AXIS Team

2018-01-01

We present an overview of the Advanced X-ray Imaging Satellite (AXIS), a probe mission concept under study to the 2020 Decadal survey. AXIS follows in the footsteps of the spectacularly successful Chandra X-ray Observatory with similar or higher angular resolution and an order of magnitude more collecting area in the 0.3-10 keV band over a 15' field of view. These capabilities are designed to attain a wide range of science goals such as (i) measuring the event horizon scale structure in AGN accretion disks and the spin of supermassive black holes through monitoring of gravitationally microlensed quasars; (ii) understanding AGN and starburst feedback in galaxies and galaxy clusters through direct imaging of winds and interaction of jets and via spatially resolved imaging of galaxies at high-z; (iii) probing the fueling of AGN by resolving the SMBH sphere of influence in nearby galaxies; (iv) investigating hierarchical structure formation and the SMBH merger rate through measurement of the occurrence rate of dual AGN and occupation fraction of SMBHs; (v) advancing SNR physics and galaxy ecology through large detailed samples of SNR in nearby galaxies; (vi) measuring the Cosmic Web through its connection to cluster outskirts. With a nominal 2028 launch, AXIS benefits from natural synergies with LSST, ELTs, ALMA, WFIRST and ATHENA, and will be a valuable precursor to Lynx. AXIS utilizes breakthroughs in the construction of light-weight X-ray optics from mono-crystalline silicon blocks, and developments in the fabrication of large format, small pixel, high readout detectors.
[Seasonal and semi-lunar changes in fish community structure in low salinity intertidal area of Yangtze estuary].

PubMed

Zhang, Heng; He, Wen-Shan; Tong, Chun-Fu; Lu, Jian-Jian

2008-05-01

Based on the survey of the fishes in low salinity intertidal area of the Yangtze estuary from spring (May) 2006 to winter (February) 2007, the seasonal and semi-lunar changes of fish species and abundances were analyzed. A total of 53 fish species were collected, most of which belonged to Cyprinidae, followed by Gobiidae, and few of other families. The fish species and average abundance were higher in spring, summer, and autumn than in winter and lower in low tides than in high tides in four seasons. Shannon-Weaver (H') value had a greater fluctuation in a tidal cycle, and was appreciably lower in low tides than in high tides. The fish species and abundance were clustered into two groups, i. e., that of winter, and of the other seasons. As for the whole year, the abundance had the highest positive correlation with water temperature, then with tide height, and lowest with water salinity.
Simple steep-axis marking technique using a corneal analyzer.

PubMed

Ng, Alex L K; Chan, Tommy C Y; Jhanji, Vishal; Cheng, George P M

2017-02-01

We describe a simple steep-axis marking technique that uses a corneal analyzer (OPD III scan) during arcuate keratotomy in femtosecond laser-assisted cataract surgery. The technique requires a single reference mark at the limbus, which does not have to be on the horizontal axis. Using the corneal analyzer, the angle between the steep axis and the reference line between the reference mark and the center of the cornea can be determined. The angle from the reference mark is used intraoperatively to locate the steep axis. This eliminates the potential error from different head positions during keratometry measurement and during traditional marking under the slitlamp. The marking technique can also be applied to toric intraocular lens implantation during cataract surgery. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Canola integration into semi-arid wheat cropping systems of the inland Pacific Northwestern USA

USDA-ARS?s Scientific Manuscript database

The inland Pacific Northwestern USA (iPNW) wheat-producing region has a diversity of environments and soils, yet it lacks crop diversity and is one of the few semi-arid wheat-growing regions without significant integration of oilseeds. Four major agroecological zones, primarily characterised by wate...
Off-Axis Seamount Lavas at 8°20' N Span the Entire Range of East Pacific Rise MORB Compositions

NASA Astrophysics Data System (ADS)

Anderson, M.; Wanless, V. D.; Perfit, M. R.; Gregg, P. M.; Fornari, D. J.; McCully, E.; Ridley, W. I.

2017-12-01

Lavas erupted at off-axis seamounts can provide a window into mantle heterogeneity and melting systematics that are not easily observed on-axis at fast-spreading mid-ocean ridges (MORs), where melts are efficiently mixed and homogenized within shallow axial magma chambers. To investigate off-axis magmatism, we systematically mapped the 8°20' N seamount chain in November of 2016 on R/V Atlantis using shipboard EM122 multibeam system and AUV Sentry. This 160-km long chain of off-axis seamounts and ridges is located perpendicular to the ridge axis, west of the East Pacific Rise (EPR) and north of the Siqueiros Fracture Zone. The high-resolution surface and AUV-based multibeam and AUV sidescan maps are combined with geochemical analyses of 300 basalt samples, collected using HOV Alvin and dredging, to evaluate magmatic plumbing and sources off-axis. Preliminary major and trace element concentrations reveal remarkable geochemical heterogeneity (including both normal and enriched basalt compositions) across the entire seamount chain and within individual seamounts. For example, (La/Sm)N contents span the entire range of known values for basalts from northern Pacific MORs and seamounts (0.45—2.76). MgO contents vary from 10.25 to 4.56 wt. % across the seamount chain and by as much as 3.61 wt. % from volcanic features sampled at an individual seamount (Beryl). Additionally, K2O/TiO2 ratios range from 4.9 to 61.3 across the seamount chain, and by as much as 54.4 at a single seamount (Beryl), indicating heterogeneous mantle sources or variable extents of melting occur at both regional and local scales. We combine the geochemical results and bathymetric maps with petrologic models to evaluate extents and depths of fractional crystallization and mantle melting in the off-axis environment.
Neurovascular-neuroenergetic coupling axis in the brain: master regulation by nitric oxide and consequences in aging and neurodegeneration.

PubMed

Lourenço, Cátia F; Ledo, Ana; Barbosa, Rui M; Laranjinha, João

2017-07-01

The strict energetic demands of the brain require that nutrient supply and usage be fine-tuned in accordance with the specific temporal and spatial patterns of ever-changing levels of neuronal activity. This is achieved by adjusting local cerebral blood flow (CBF) as a function of activity level - neurovascular coupling - and by changing how energy substrates are metabolized and shuttled amongst astrocytes and neurons - neuroenergetic coupling. Both activity-dependent increase of CBF and O 2 and glucose utilization by active neural cells are inextricably linked, establishing a functional metabolic axis in the brain, the neurovascular-neuroenergetic coupling axis. This axis incorporates and links previously independent processes that need to be coordinated in the normal brain. We here review evidence supporting the role of neuronal-derived nitric oxide ( • NO) as the master regulator of this axis. Nitric oxide is produced in tight association with glutamatergic activation and, diffusing several cell diameters, may interact with different molecular targets within each cell type. Hemeproteins such as soluble guanylate cyclase, cytochrome c oxidase and hemoglobin, with which • NO reacts at relatively fast rates, are but a few of the key in determinants of the regulatory role of • NO in the neurovascular-neuroenergetic coupling axis. Accordingly, critical literature supporting this concept is discussed. Moreover, in view of the controversy regarding the regulation of catabolism of different neural cells, we further discuss key aspects of the pathways through which • NO specifically up-regulates glycolysis in astrocytes, supporting lactate shuttling to neurons for oxidative breakdown. From a biomedical viewpoint, derailment of neurovascular-neuroenergetic axis is precociously linked to aberrant brain aging, cognitive impairment and neurodegeneration. Thus, we summarize current knowledge of how both neurovascular and neuroenergetic coupling are compromised in
Generation of irradiance patterns using a semi-spherical meter of two degrees of freedom

NASA Astrophysics Data System (ADS)

Tecpoyotl-Torres, M.; Vera-Dimas, J. G.; Escobedo-Alatorre, J.; Sánchez-Mondragón, J.; Torres-Cisneros, M.; Cabello-Ruiz, R.; Varona, J.

2011-09-01

The meter device presented in this work consists of a photo-detector mounted on the mechanism of a mobile rectangular arc. One stepper motor located on the lateral axis of the device displaces the sensor along a semi-circular trajectory of 170°, almost half meridians. Another motor located at the base of the device enables 360° rotation of the illumination source under test. This arrangement effectively produces a semi-spherical volume for the sensor to move within. The number of measurement points is determined by programming the two stepper motors. Also, the use of a single photo-sensor ensures uniformity in the measurements. The mechanical structure provides enough rigidity for supporting the accuracy required by the data acquisition circuitry based on a DSPIC. Measurement of illumination sources of different sizes is possible by using adjustable lengths of the mobile base and the ring for a maximum lamp length of 0.16 m. Because this work is partially supported by a private entity interested in the characterization of its products, especial attention has been given to the luminaries based on LED technology with divergent beams. The received power by the detector is useful to obtain the irradiance profile of the lighting source under test. The meter device presented herein is a low-cost prototype designed and fabricated using recyclable materials only such as "electronic waste".
Neutral axis determination of full size concrete structures using coda wave measurements

NASA Astrophysics Data System (ADS)

Jiang, Hanwan; Zhan, Hanyu; Zhuang, Chenxu; Jiang, Ruinian

2018-03-01

Coda waves experiencing multiple scattering behaviors are sensitive to weak changes occurring in media. In this paper, a typical four-point bending test with varied external loads is conducted on a 30-meter T-beam that is removed from a bridge after being in service for 15 years, and the coda wave signals are collected with a couple of sources-receivers pairs. Then the observed coda waves at different loads are compared to calculate their relative velocity variations, which are utilized as the parameter to distinct the compression and tensile zones as well as determine the neutral axis position. Without any prior knowledge of the concrete beam, the estimated axis position agrees well with the associated strain gage measurement results, and the zones bearing stress and tension behaviors are indicated. The presented work offers significant potential for Non-Destructive Testing and Evaluation of full-size concrete structures in future work.
Determination of Flux rope axis for GS reconstruction

NASA Astrophysics Data System (ADS)

Tian, A.; Shi, Q.; Bai, S.; Zhang, S.

2016-12-01

It is important to give the axis direction and velocity of a magnetic flux ropes before employing Grad-Shafranov reconstruction. The ability of single-satellite based MVA (MVAB and CMVA) and multi-satellite based MDD methods in finding the invariant axis are tested by a model. The choice of principal axis given by MVA along the aimed direction is dependent on the distance of the path from the flux-rope axis. The MDD results are influenced by the ratio of Noise level/separation to the gradient of the structure. An accurate axial direction will be obtained when the ratio is less than 1. By a model, an example with failed HT method is displayed indicating the importance of the STD method in obtaining the velocity of such a structure. The applicability of trial and error method by Hu and Sonnerup(2012) was also used and discussed. Finally, all above methods were applied to a flux-rope observed by Cluster. It shows that the GS method can be easily carried out in the case of clearly known dimensionality and velocity.
Phytochemicals for taming agitated immune-endocrine-neural axis.

PubMed

Patel, Seema

2017-07-01

Homeostasis of immune-endocrine-neural axis is paramount for human health. If this axis gets agitated due to age, genetic variations, environmental exposures or lifestyle assaults, a cascade of adverse reactions occurs in human body. Cytokines, hormones and neurotransmitters, the effector molecules of this axis behave erratically, leading to a gamut of neural, endocrine, autoimmune, and metabolic diseases. Current panel of drugs can tackle some of them but not in a sustainable, benign way as a myriad of side effects, causal of them have been documented. In this context, phytochemicals, the secondary metabolites of plants seem beneficial. These bioactive constituents encompassing polyphenols, alkaloids, flavonoids, terpenoids, tannins, lignans, stilbenoids (resveratrol), saponins, polysaccharides, glycosides, and lectins etc. have been proven to exert antioxidant, anti-inflammatory, hypolipidemic, hypotensive, antidiabetic, anticancer, immunomodulatory, anti-allergic, analgesic, hepatoprotective, neuroprotective, dermatoprotective, and antimicrobial properties, among a litany of other biological effects. This review presents a holistic perspective of common afflictions resultant of immune-endocrine-neural axis disruption, and the phytochemicals capable of restoring their normalcy and mitigating the ailments. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Intracalibration of particle detectors on a three-axis stabilized geostationary platform

NASA Astrophysics Data System (ADS)

Rowland, W.; Weigel, R. S.

2012-11-01

We describe an algorithm for intracalibration of measurements from plasma or energetic particle detectors on a three-axis stabilized platform. Modeling and forecasting of Earth's radiation belt environment requires data from particle instruments, and these data depend on measurements which have an inherent calibration uncertainty. Pre-launch calibration is typically performed, but on-orbit changes in the instrument often necessitate adjustment of calibration parameters to mitigate the effect of these changes on the measurements. On-orbit calibration practices for particle detectors aboard spin-stabilized spacecraft are well established. Three-axis stabilized platforms, however, pose unique challenges even when comparisons are being performed between multiple telescopes measuring the same energy ranges aboard the same satellite. This algorithm identifies time intervals when different telescopes are measuring particles with the same pitch angles. These measurements are used to compute scale factors which can be multiplied by the pre-launch geometric factor to correct any changes. The approach is first tested using measurements from GOES-13 MAGED particle detectors over a 5-month time period in 2010. We find statistically significant variations which are generally on the order of 5% or less. These results do not appear to be dependent on Poisson statistics nor upon whether a dead time correction was performed. When applied to data from a 5-month interval in 2011, one telescope shows a 10% shift from the 2010 scale factors. This technique has potential for operational use to help maintain relative calibration between multiple telescopes aboard a single satellite. It should also be extensible to inter-calibration between multiple satellites.
Major Mid-Miocene Climate Change In The Transantarctic Mountains

NASA Astrophysics Data System (ADS)

Ashworth, A. C.; Lewis, A. R.; Marchant, D. R.

2007-12-01

Independent lines of evidence from paleoecology, glacial geology and marine isotopes indicate major climate change in the Dry Valley sector of the Transantarctic Mountains (TAM) at c.14 Ma. A fossil assemblage of pollen and spores, freshwater diatoms, ostracods, mosses, and insect remains has been recovered from lacustrine sediments preserved in a small morainic lake basin in the western Olympus Range. The diatom assemblage indicates that the lake existed for >103yr and was ice-free during summers. Based on the moss and insect fossils the minimum mean summer temperature (MST- Dec-Feb) was 2°C but could have been as high as 5°C. Today at the site the MST is c. -15°C. The lake-marginal vegetation was a sparse tundra dominated by mosses and liverworts. Based on pollen, Nothofagus (southern beech) was part of the lowland regional vegetation and individual dwarfed shrubs may have grown on the slopes surrounding the lake basin. The age of the deposits is well-constrained by an 40Ar/39Ar age of 14.11 ± 0.11 Ma from an in situ volcanic ash within related lacustrine sediments. Based on an independent study of the glacial stratigraphy of the western Wright and McKelvey valleys, diamictites of a wet-based glacial regime had been replaced by those of cold-based regime by 13.85 ± 0.03 Ma. The drop in temperatures and the cessation of meltwater at c. 14 Ma would have caused the regional extinction of all plant and insect life with the exception of the hardiest of soil-dwelling organisms. Paleobotanical evidence indicates that Antarctica had likely been vegetated throughout the Cenozoic, with forests replaced by tundra during the early Oligocene. The mid-Miocene extinction marks the end of tundra in the interior of Antarctica and its replacement by the polar desert biota which exists today. Changes in δ18O and Mg/Ca ratios from different sectors of the Southern Ocean indicate sea surface temperature cooling and ice sheet growth between 13.8 - 14.2 Ma. The close correlation
Diamond Machining of an Off-Axis Biconic Aspherical Mirror

NASA Technical Reports Server (NTRS)

Ohl, Raymond G.; Preuss, Werner; Sohn, Alex; MacKenty, John

2009-01-01

Two diamond-machining methods have been developed as part of an effort to design and fabricate an off-axis, biconic ellipsoidal, concave aluminum mirror for an infrared spectrometer at the Kitt Peak National Observatory. Beyond this initial application, the methods can be expected to enable satisfaction of requirements for future instrument mirrors having increasingly complex (including asymmetrical), precise shapes that, heretofore, could not readily be fabricated by diamond machining or, in some cases, could not be fabricated at all. In the initial application, the mirror is prescribed, in terms of Cartesian coordinates x and y, by aperture dimensions of 94 by 76 mm, placements of -2 mm off axis in x and 227 mm off axis in y, an x radius of curvature of 377 mm, a y radius of curvature of 407 mm, an x conic constant of 0.078, and a y conic constant of 0.127. The aspect ratio of the mirror blank is about 6. One common, "diamond machining" process uses single-point diamond turning (SPDT). However, it is impossible to generate the required off-axis, biconic ellipsoidal shape by conventional SPDT because (1) rotational symmetry is an essential element of conventional SPDT and (2) the present off-axis biconic mirror shape lacks rotational symmetry. Following conventional practice, it would be necessary to make this mirror from a glass blank by computer-controlled polishing, which costs more than diamond machining and yields a mirror that is more difficult to mount to a metal bench. One of the two present diamond machining methods involves the use of an SPDT machine equipped with a fast tool servo (FTS). The SPDT machine is programmed to follow the rotationally symmetric asphere that best fits the desired off-axis, biconic ellipsoidal surface. The FTS is actuated in synchronism with the rotation of the SPDT machine to generate the difference between the desired surface and the best-fit rotationally symmetric asphere. In order to minimize the required stroke of the FTS
Field assessment of semi-aerobic condition and the methane correction factor for the semi-aerobic landfills provided by IPCC guidelines

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

Jeong, Sangjae; Nam, Anwoo; Yi, Seung-Muk

Highlights: • CH{sub 4}/CO{sub 2} and CH{sub 4} + CO{sub 2}% are proposed as indices to evaluate semi-aerobic landfills. • A landfill which CH{sub 4}/CO{sub 2} > 1.0 is difficult to be categorized as semi-aerobic landfill. • Field conditions should be carefully investigated to determine landfill types. • The MCF default value for semi-aerobic landfills underestimates the methane emissions. - Abstract: According to IPCC guidelines, a semi-aerobic landfill site produces one-half of the amount of CH{sub 4} produced by an equally-sized anaerobic landfill site. Therefore categorizing the landfill type is important on greenhouse gas inventories. In order to assess semi-aerobicmore » condition in the sites and the MCF value for semi-aerobic landfill, landfill gas has been measured from vent pipes in five semi-aerobically designed landfills in South Korea. All of the five sites satisfied requirements of semi-aerobic landfills in 2006 IPCC guidelines. However, the ends of leachate collection pipes which are main entrance of air in the semi-aerobic landfill were closed in all five sites. The CH{sub 4}/CO{sub 2} ratio in landfill gas, indicator of aerobic and anaerobic decomposition, ranged from 1.08 to 1.46 which is higher than the values (0.3–1.0) reported for semi-aerobic landfill sites and is rather close to those (1.0–2.0) for anaerobic landfill sites. The low CH{sub 4} + CO{sub 2}% in landfill gas implied air intrusion into the landfill. However, there was no evidence that air intrusion has caused by semi-aerobic design and operation. Therefore, the landfills investigated in this study are difficult to be classified as semi-aerobic landfills. Also MCF of 0.5 may significantly underestimate methane emissions compared to other researches. According to the carbon mass balance analyses, the higher MCF needs to be proposed for semi-aerobic landfills. Consequently, methane emission estimate should be based on field evaluation for the semi-aerobically designed
VizieR Online Data Catalog: Orbital parameters of 341 new binaries (Murphy+, 2018)

NASA Astrophysics Data System (ADS)

Murphy, S. J.; Moe, M.; Kurtz, D. W.; Bedding, T.; Shibahashi, H.; Boffin, H. M. J.

2018-01-01

Kepler targets with effective temperatures between 6600 and 10000K have been investigated for pulsational phase modulation that can be attributed to binary orbital motion. For each target, we provide a binary status, which also reflects whether or not the target pulsates. For the binary systems, we provide the Kepler Input Catalogue (KIC) number, as well as the binary orbital elements: the period, semi-major axis, eccentricity, longitude of periastron, time of periastron passage, binary mass function and a calculated radial velocity semi-amplitude. (3 data files).
Phase gradient algorithm based on co-axis two-step phase-shifting interferometry and its application

NASA Astrophysics Data System (ADS)

Wang, Yawei; Zhu, Qiong; Xu, Yuanyuan; Xin, Zhiduo; Liu, Jingye

2017-12-01

A phase gradient method based on co-axis two-step phase-shifting interferometry, is used to reveal the detailed information of a specimen. In this method, the phase gradient distribution can only be obtained by calculating both the first-order derivative and the radial Hilbert transformation of the intensity difference between two phase-shifted interferograms. The feasibility and accuracy of this method were fully verified by the simulation results for a polystyrene sphere and a red blood cell. The empirical results demonstrated that phase gradient is sensitive to changes in the refractive index and morphology. Because phase retrieval and tedious phase unwrapping are not required, the calculation speed is faster. In addition, co-axis interferometry has high spatial resolution.
20 CFR 418.1260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false What major life-changing event evidence will we not accept? 418.1260 Section 418.1260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare Part B Income-Related Monthly Adjustment Amount Determinations Using A More Recent Tax...
20 CFR 418.1260 - What major life-changing event evidence will we not accept?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false What major life-changing event evidence will we not accept? 418.1260 Section 418.1260 Employees' Benefits SOCIAL SECURITY ADMINISTRATION MEDICARE SUBSIDIES Medicare Part B Income-Related Monthly Adjustment Amount Determinations Using A More Recent Tax...
Application of External Axis in Robot-Assisted Thermal Spraying

NASA Astrophysics Data System (ADS)

Deng, Sihao; Fang, Dandan; Cai, Zhenhua; Liao, Hanlin; Montavon, Ghislain

2012-12-01

Currently, industrial robots are widely used in the process of thermal spraying because of their high efficiency, security, and repeatability. Although robots are found suitable for use in industrial productions, they have some natural disadvantages because of their six-axis mechanical linkages. When a robot performs a series of stages of production, it could be hard to move from one to another because a few axes reach their limit value. For this reason, an external axis should be added to the robot system to extend the reachable space of the robots. This article concerns the application of external axis on ABB robots in thermal spraying and the different methods of off-line programming with external axis in the virtual environment. The developed software toolkit was applied to coat real workpiece with a complex geometry in atmospheric plasma spraying).
Stress and the HPA Axis: Balancing Homeostasis and Fertility

PubMed Central

Whirledge, Shannon

2017-01-01

An organism’s reproductive fitness is sensitive to the environment, integrating cues of resource availability, ecological factors, and hazards within its habitat. Events that challenge the environment of an organism activate the central stress response system, which is primarily mediated by the hypothalamic–pituitary–adrenal (HPA) axis. The regulatory functions of the HPA axis govern the cardiovascular and metabolic system, immune functions, behavior, and reproduction. Activation of the HPA axis by various stressors primarily inhibits reproductive function and is able to alter fetal development, imparting a biological record of stress experienced in utero. Clinical studies and experimental data indicate that stress signaling can mediate these effects through direct actions in the brain, gonads, and embryonic tissues. This review focuses on the mechanisms by which stress activation of the HPA axis impacts fertility and fetal development. PMID:29064426
Validity of the semi-infinite tumor model in diffuse reflectance spectroscopy for epithelial cancer diagnosis: a Monte Carlo study

NASA Astrophysics Data System (ADS)

Zhu, Caigang; Liu, Quan

2011-08-01

The accurate understanding of optical properties of human tissues plays an important role in the optical diagnosis of early epithelial cancer. Many inverse models used to determine the optical properties of a tumor have assumed that the tumor was semi-infinite, which infers infinite width and length but finite thickness. However, this simplified assumption could lead to large errors for small tumor, especially at the early stages. We used a modified Monte Carlo code, which is able to simulate light transport in a layered tissue model with buried tumor-like targets, to investigate the validity of the semi-infinite tumor assumption in two common epithelial tissue models: a squamous cell carcinoma (SCC) tissue model and a basal cell carcinoma (BCC) tissue model. The SCC tissue model consisted of three layers, i.e. the top epithelium, the middle tumor and the bottom stroma. The BCC tissue model also consisted of three layers, i.e. the top epidermis, the middle tumor and the bottom dermis. Diffuse reflectance was simulated for two common fiber-optic probes. In one probe, both source and detector fibers were perpendicular to the tissue surface; while in the other, both fibers were tilted at 45 degrees relative to the normal axis of the tissue surface. It was demonstrated that the validity of the semi-infinite tumor model depends on both the fiber-optic probe configuration and the tumor dimensions. Two look-up tables, which relate the validity of the semi-infinite tumor model to the tumor width in terms of the source-detector separation, were derived to guide the selection of appropriate tumor models and fiber optic probe configuration for the optical diagnosis of early epithelial cancers.
Chemokine GPCR Signaling Inhibits β-Catenin during Zebrafish Axis Formation

PubMed Central

Wu, Shu-Yu; Shin, Jimann; Sepich, Diane S.; Solnica-Krezel, Lilianna

2012-01-01

Embryonic axis formation in vertebrates is initiated by the establishment of the dorsal Nieuwkoop blastula organizer, marked by the nuclear accumulation of maternal β-catenin, a transcriptional effector of canonical Wnt signaling. Known regulators of axis specification include the canonical Wnt pathway components that positively or negatively affect β-catenin. An involvement of G-protein coupled receptors (GPCRs) was hypothesized from experiments implicating G proteins and intracellular calcium in axis formation, but such GPCRs have not been identified. Mobilization of intracellular Ca2+ stores generates Ca2+ transients in the superficial blastomeres of zebrafish blastulae when the nuclear accumulation of maternal β-catenin marks the formation of the Nieuwkoop organizer. Moreover, intracellular Ca2+ downstream of non-canonical Wnt ligands was proposed to inhibit β-catenin and axis formation, but mechanisms remain unclear. Here we report a novel function of Ccr7 GPCR and its chemokine ligand Ccl19.1, previously implicated in chemotaxis and other responses of dendritic cells in mammals, as negative regulators of β-catenin and axis formation in zebrafish. We show that interference with the maternally and ubiquitously expressed zebrafish Ccr7 or Ccl19.1 expands the blastula organizer and the dorsoanterior tissues at the expense of the ventroposterior ones. Conversely, Ccr7 or Ccl19.1 overexpression limits axis formation. Epistatic analyses demonstrate that Ccr7 acts downstream of Ccl19.1 ligand and upstream of β-catenin transcriptional targets. Moreover, Ccl19/Ccr7 signaling reduces the level and nuclear accumulation of maternal β-catenin and its axis-inducing activity and can also inhibit the Gsk3β -insensitive form of β-catenin. Mutational and pharmacologic experiments reveal that Ccr7 functions during axis formation as a GPCR to inhibit β-catenin, likely by promoting Ca2+ transients throughout the blastula. Our study delineates a novel negative, Gsk3�
Design and realization of photoelectric instrument binocular optical axis parallelism calibration system

NASA Astrophysics Data System (ADS)

Ying, Jia-ju; Chen, Yu-dan; Liu, Jie; Wu, Dong-sheng; Lu, Jun

2016-10-01

The maladjustment of photoelectric instrument binocular optical axis parallelism will affect the observe effect directly. A binocular optical axis parallelism digital calibration system is designed. On the basis of the principle of optical axis binocular photoelectric instrument calibration, the scheme of system is designed, and the binocular optical axis parallelism digital calibration system is realized, which include four modules: multiband parallel light tube, optical axis translation, image acquisition system and software system. According to the different characteristics of thermal infrared imager and low-light-level night viewer, different algorithms is used to localize the center of the cross reticle. And the binocular optical axis parallelism calibration is realized for calibrating low-light-level night viewer and thermal infrared imager.
Speed and Torque Control Strategies for Loss Reduction of Vertical Axis Wind Turbines

NASA Astrophysics Data System (ADS)

Argent, Michael; McDonald, Alasdair; Leithead, Bill; Giles, Alexander

2016-09-01

This paper builds on the work into modelling the generator losses for Vertical Axis Wind Turbines from their intrinsic torque cycling to investigate the effects of aerodynamic inefficiencies caused by the varying rotational speed resulting from different torque control strategies to the cyclic torque. This is achieved by modelling the wake that builds up from the rotation of the VAWT rotor to investigate how the wake responds to a changing rotor speed and how this in turn affects the torque produced by the blades as well as the corresponding change in generator losses and any changes to the energy extracted by the wind turbine rotor.
Along-axis variations in seafloor spreading in the MARK area

NASA Astrophysics Data System (ADS)

Karson, J. A.; Thompson, G.; Humphris, S. E.; Bryan, W. B.; Edmond, J. M.

1987-08-01

Recent investigations with the manned submersible Alvin and the Angus deep-towed camera sled greatly extended the known range of variations in the style of seafloor spreading along the axis of the Mid-Atlantic Ridge. Five transects of the spreading center at intervals of 10-20 km south of the Kane Fracture Zone at 24 deg N latitude demonstate dramatic changes in the style and magnitude of tectonic extension, development of the neovolcanic zone, expression of hydrothermal venting, types of lithologic exposures, and morphology of the median valley.
Excitation of the earth's rotational axis by recent glacial discharges

NASA Technical Reports Server (NTRS)

Gasperini, P.; Sabadini, R.; Yuen, D. A.

1986-01-01

The effects of present-day glacial discharges and the growth of the Antarctic ice sheet on exciting the earth's rotational axis are studied. Glacial forcing could cause a maximum change in J2 of about one-third of the observed amount, for the Maxwell rheology and for Burgers' body models with a long-term, lower-mantle viscosity greater than about 10 to the 23rd P. For transient rheologies the amount of excitation due to glacial melting decreases. Polar wander is not much excited by recent glacial melting for the various types of rheologies examined.
The environmental contaminant tributyltin leads to abnormalities in different levels of the hypothalamus-pituitary-thyroid axis in female rats.

PubMed

Andrade, Marcelle Novaes; Santos-Silva, Ana Paula; Rodrigues-Pereira, Paula; Paiva-Melo, Francisca Diana; de Lima Junior, Niedson Correa; Teixeira, Mariana Pires; Soares, Paula; Dias, Glaecir Roseni Munstock; Graceli, Jones Bernardes; de Carvalho, Denise Pires; Ferreira, Andrea Claudia Freitas; Miranda-Alves, Leandro

2018-06-11

Tributyltin is a biocide used in nautical paints, aiming to reduce fouling of barnacles in ships. Despite the fact that many effects of TBT on marine species are known, studies in mammals have been limited, especially those evaluating its effect on the function of the hypothalamus-pituitary-thyroid (HPT) axis. The aim of this study was to investigate the effects of subchronic exposure to TBT on the HPT axis in female rats. Female Wistar rats received vehicle, TBT 200 ng kg -1 BW d -1 or 1000 ng kg -1 BW d -1 orally by gavage for 40 d. Hypothalamus, pituitary, thyroid, liver and blood samples were collected. TBT200 and TBT1000 thyroids showed vacuolated follicular cells, with follicular hypertrophy and hyperplasia. An increase in epithelial height and a decrease in the thyroid follicle and colloid area were observed in TBT1000 rats. Moreover, an increase in the epithelium/colloid area ratio was observed in both TBT groups. Lower TRH mRNA expression was observed in the hypothalami of TBT200 and TBT1000 rats. An increase in Dio1 mRNA levels was observed in the hypothalamus and thyroid in TBT1000 rats only. TSH serum levels were increased in TBT200 rats. In TBT1000 rats, there was a decrease in total T4 serum levels compared to control rats, whereas T3 serum levels did not show significant alterations. We conclude that TBT exposure can promote critical abnormalities in the HPT axis, including changes in TRH mRNA expression and serum TSH and T4 levels, in addition to affecting thyroid morphology. These findings demonstrate that TBT disrupts the HPT axis. Additionally, the changes found in thyroid hormones suggest that TBT may interfere with the peripheral metabolism of these hormones, an idea corroborated by the observed changes in Dio1 mRNA levels. Therefore, TBT exposition might interfere not only with the thyroid axis but also with thyroid hormone metabolism. Copyright © 2018 Elsevier Ltd. All rights reserved.
A Semi-parametric Transformation Frailty Model for Semi-competing Risks Survival Data

PubMed Central

Jiang, Fei; Haneuse, Sebastien

2016-01-01

In the analysis of semi-competing risks data interest lies in estimation and inference with respect to a so-called non-terminal event, the observation of which is subject to a terminal event. Multi-state models are commonly used to analyse such data, with covariate effects on the transition/intensity functions typically specified via the Cox model and dependence between the non-terminal and terminal events specified, in part, by a unit-specific shared frailty term. To ensure identifiability, the frailties are typically assumed to arise from a parametric distribution, specifically a Gamma distribution with mean 1.0 and variance, say, σ2. When the frailty distribution is misspecified, however, the resulting estimator is not guaranteed to be consistent, with the extent of asymptotic bias depending on the discrepancy between the assumed and true frailty distributions. In this paper, we propose a novel class of transformation models for semi-competing risks analysis that permit the non-parametric specification of the frailty distribution. To ensure identifiability, the class restricts to parametric specifications of the transformation and the error distribution; the latter are flexible, however, and cover a broad range of possible specifications. We also derive the semi-parametric efficient score under the complete data setting and propose a non-parametric score imputation method to handle right censoring; consistency and asymptotic normality of the resulting estimators is derived and small-sample operating characteristics evaluated via simulation. Although the proposed semi-parametric transformation model and non-parametric score imputation method are motivated by the analysis of semi-competing risks data, they are broadly applicable to any analysis of multivariate time-to-event outcomes in which a unit-specific shared frailty is used to account for correlation. Finally, the proposed model and estimation procedures are applied to a study of hospital readmission among
Potential soil organic carbon stocks in semi arid areas under climate change scenarios: an application of CarboSOIL model in northern Egypt

NASA Astrophysics Data System (ADS)

Muñoz-Rojas, Miriam; Abd-Elmabod, Sameh K.; Jordán, Antonio; Zavala, Lorena M.; Anaya-Romero, Maria; De la Rosa, Diego

2014-05-01

1. INTRODUCTION Climate change is predicted to have a large impact on semi arid areas which are often degraded and vulnerable to environmental changes (Muñoz-Rojas et al., 2012a; 2012b; 2013). However, these areas might play a key role in mitigation of climate change effects through sequestration of carbon in soils (United Nations, 2011). At the same time, increasing organic carbon in these environments could be beneficial for soil erosion control, soil fertility and, ultimately, food production (Lal, 2004). Several approaches have been carried out to evaluate climate change impacts on soil organic carbon (SOC) stocks, but soil carbon models are amongst the most effective tools to assess C stocks, dynamics and distribution and to predict trends under climate change scenarios (Jones et al., 2005 ). CarboSOIL is an empirical model based on regression techniques and developed to predict SOC contents at standard soil depths of 0 to 25, 25 to 50 and 50-75 cm (Muñoz-Rojas et al., 2013). CarboSOIL model has been designed as a GIS-integrated tool and is a new component of the agroecological decision support system for land evaluation MicroLEIS DSS (De la Rosa et al., 2004). 2. GENERAL METHODS In this research, CarboSOIL was applied in El-Fayoum depression, a semi arid region located in northern Egypt with a large potential for agriculture (Abd-Elmabod et al, 2012). The model was applied in a total of six soil-units classified according the USDA Soil Taxonomy system within the orders Entisols and Aridisols under different climate climate change scenarios. Global climate models based on the Organisation for Economic Co-operation and Development (Agrawala at al., 2004) and the Intergovernmental Panel on Climate Change (IPCC, 2007) were applied to predict short-, medium- and long-term trends (2030, 2050 and 2100) of SOC dynamics and sequestration at different soil depths (0-25, 25-50 and 50-75) and land use types (irrigated areas, olive groves, wheat, cotton and other annual
Topography alters tree growth–climate relationships in a semi-arid forested catchment

DOE PAGES

Adams, Hallie R.; Barnard, Holly R.; Loomis, Alexander K.

2014-11-26

Topography and climate play an integral role in the spatial variability and annual dynamics of aboveground carbon sequestration. Despite knowledge of vegetation–climate–topography relationships on the landscape and hillslope scales, little is known about the influence of complex terrain coupled with hydrologic and topoclimatic variation on tree growth and physiology at the catchment scale. Climate change predictions for the semi-arid, western United States include increased temperatures, more frequent and extreme drought events, and decreases in snowpack, all of which put forests at risk of drought induced mortality and enhanced susceptibility to disturbance events. In this study, we determine how species-specific treemore » growth patterns and water use efficiency respond to interannual climate variability and how this response varies with topographic position. We found that Pinus contorta and Pinus ponderosa both show significant decreases in growth with water-limiting climate conditions, but complex terrain mediates this response by controlling moisture conditions in variable topoclimates. Foliar carbon isotope analyses show increased water use efficiency during drought for Pinus contorta, but indicate no significant difference in water use efficiency of Pinus ponderosa between a drought year and a non-drought year. The responses of the two pine species to climate indicate that semi-arid forests are especially susceptible to changes and risks posed by climate change and that topographic variability will likely play a significant role in determining the future vegetation patterns of semi-arid systems.« less

Effects of astigmatic axis orientation on postural stabilization with stationary equilibrium

NASA Astrophysics Data System (ADS)

Kanazawa, Masatsugu; Uozato, Hiroshi; Asakawa, Ken; Kawamorita, Takushi

2018-02-01

We evaluated 15 healthy participants by assessing their maintenance of postural control while standing on a platform stabilometer for 1 min under the following conditions: eyes open; eyes open with + 3.00 D on both eyes on same directions (45, 90, 135, 180 degree axis); right eye on 45 degree axis and left eye on 135 degree axis (inverted V-pattern), and right eye on 135 degree axis and left eye on axis 45 degree axis (V-pattern). The differences in the linear length, area and maximum velocity of center of pressure during postural control before and after the six types of positive cylinder-oriented axes were analyzed. Comparing the antero-posterior lengths and antero-posterior maximum velocities, there were significant differences between the V-pattern condition and the six other conditions. Astigmatic defocus in the antagonistic axes conditions, particularly the V-pattern condition, affects postural control of antero-posterior sway (143/150).
"Engage" therapy: Prediction of change of late-life major depression.

PubMed

Alexopoulos, George S; O'Neil, Robert; Banerjee, Samprit; Raue, Patrick J; Victoria, Lindsay W; Bress, Jennifer N; Pollari, Cristina; Arean, Patricia A

2017-10-15

Engage grew out of the need for streamlined psychotherapies that can be accurately used by community therapists in late-life depression. Engage was based on the view that dysfunction of reward networks is the principal mechanism mediating depressive symptoms. Accordingly, Engage uses "reward exposure" (exposure to meaningful activities) and assumes that repeated activation of reward networks will normalize these systems. This study examined whether change in a behavioral activation scale, an index of reward system function, predicts change in depressive symptomatology. The participants (N = 48) were older adults with major depression treated with 9 weekly sessions of Engage and assessed 27 weeks after treatment. Depression was assessed with the 24-item Hamilton Depression Rating Scale (HAM-D) and behavioral activation with the four subscales of Behavioral Activation for Depression Scale (activation, avoidance/rumination, work impairment, social impairment) at baseline, 6 weeks (mid-treatment), 9 weeks (end of treatment), and 36 weeks. Change only in the Activation subscale during successive periods of assessment predicted depression severity (HAM-D) at the end of each period (F 1, 47 = 21.05, p<0.0001). An increase of one standard deviation in the Activation score resulted in a 2.04 (95% CI: 1.17-2.92) point decrease in HAM-D. For every one point increase in the Activation score, HAM-D was decreased by 0.22 points (95% CI: 0.12-0.31). No comparison group. Partial overlap of Activation Subscale with HAM-D, lack of detailed neurocognitive assessment and social support. Change in behavioral activation predicts improvement of depressive symptoms and signs in depressed older adults treated with Engage. Copyright © 2017. Published by Elsevier B.V.
Brain-gut-microbiota axis in Parkinson's disease.

PubMed

Mulak, Agata; Bonaz, Bruno

2015-10-07

Parkinson's disease (PD) is characterized by alpha-synucleinopathy that affects all levels of the brain-gut axis including the central, autonomic, and enteric nervous systems. Recently, it has been recognized that the brain-gut axis interactions are significantly modulated by the gut microbiota via immunological, neuroendocrine, and direct neural mechanisms. Dysregulation of the brain-gut-microbiota axis in PD may be associated with gastrointestinal manifestations frequently preceding motor symptoms, as well as with the pathogenesis of PD itself, supporting the hypothesis that the pathological process is spread from the gut to the brain. Excessive stimulation of the innate immune system resulting from gut dysbiosis and/or small intestinal bacterial overgrowth and increased intestinal permeability may induce systemic inflammation, while activation of enteric neurons and enteric glial cells may contribute to the initiation of alpha-synuclein misfolding. Additionally, the adaptive immune system may be disturbed by bacterial proteins cross-reacting with human antigens. A better understanding of the brain-gut-microbiota axis interactions should bring a new insight in the pathophysiology of PD and permit an earlier diagnosis with a focus on peripheral biomarkers within the enteric nervous system. Novel therapeutic options aimed at modifying the gut microbiota composition and enhancing the intestinal epithelial barrier integrity in PD patients could influence the initial step of the following cascade of neurodegeneration in PD.
Reduced oxygen cost of running is related to alignment of the resultant GRF and leg axis vector: A pilot study.

PubMed

Moore, I S; Jones, A M; Dixon, S J

2016-07-01

This pilot study investigated whether a 10-week running program (10wkRP), which reduced the oxygen cost of running, affected resultant ground reaction force (GRF), leg axis alignment, joint moment characteristics, and gear ratios. Ten novice, female runners completed a 10wkRP. Running kinematics and kinetics, in addition to oxygen consumption ( V ˙ O 2 ) during steady-state running, were recorded pre- and post-10wkRP. V ˙ O 2 decreased (8%) from pre-10wkRP to post-10wkRP. There was a better alignment of the resultant GRF and leg axis at peak propulsion post-10wkRP compared with pre-10wkRP (10.8 ± 4.9 vs 1.6 ± 1.2°), as the resultant GRF vector was applied 7 ± 0.6° (P = 0.008) more horizontally. There were shorter external ankle moment arms (24%) and smaller knee extensor moments (23%) at peak braking post-10wkRP. The change in V ˙ O 2 was associated with the change in alignment of the resultant GRF and leg axis (rs = 0.88, P = 0.003). As runners became more economical, they exhibited a more aligned resultant GRF vector and leg axis at peak propulsion. This appears to be a self-optimization strategy that may improve performance. Additionally, changes to external ankle moment arms indicated beneficial low gear ratios were achieved at the time of peak braking force. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Depth-resolved birefringence and differential optical axis orientation measurements with fiber-based polarization-sensitive optical coherence tomography.

PubMed

Guo, Shuguang; Zhang, Jun; Wang, Lei; Nelson, J Stuart; Chen, Zhongping

2004-09-01

Conventional polarization-sensitive optical coherence tomography (PS-OCT) can provide depth-resolved Stokes parameter measurements of light reflected from turbid media. A new algorithm that takes into account changes in the optical axis is introduced to provide depth-resolved birefringence and differential optical axis orientation images by use of fiber-based PS-OCT. Quaternion, a convenient mathematical tool, is used to represent an optical element and simplify the algorithm. Experimental results with beef tendon and rabbit tendon and muscle show that this technique has promising potential for imaging the birefringent structure of multiple-layer samples with varying optical axes.
General versus gender-specific attributes of the psychology major.

PubMed

McCray, Jason A; King, Alan R; Bailly, Matthew D

2005-04-01

In the present study, the authors extended the search for general and gender-specific factors associated with the selection of psychology as a college major by using the Family Environment Scale (FES; R. H. Moos & B. S. Moos, 1994) and Coolidge Axis II Inventory (CATI; F. L. Coolidge & M. M. Merwin, 1992). The findings were restricted to one general (Schizoid) and one gender-specific (Self-Defeating) set of personality traits that seemed to be associated with the selection of a college major. The intuitive role of many presumed gender-specific factors (e.g., women are more open to discussing personal problems with others) may prove difficult to establish empirically.
Warping and tearing of misaligned circumbinary disks around eccentric supermassive black hole binaries

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

Hayasaki, K.; Sohn, B.W.; Jung, T.

2015-07-01

We study the warping and tearing of a geometrically thin, non-self-gravitating disk surrounding binary supermassive black holes on an eccentric orbit. The circumbinary disk is significantly misaligned with the binary orbital plane, and is subject to the time-dependent tidal torques. In principle, such a disk is warped and precesses, and is torn into mutually misaligned rings in the region, where the tidal precession torques are stronger than the local viscous torques. We derive the tidal-warp and tearing radii of the misaligned circumbinary disks around eccentric SMBH binaries. We find that in disks with the viscosity parameter α larger than amore » critical value depending on the disk aspect ratio, the disk warping appears outside the tearing radius. This condition is expressed for small amplitude warps as α > √H/(3r) for H/r∼<0.1, where H is the disk scale height. If α < √H/(3r), only the disk tearing occurs because the tidal warp radius is inside the tearing radius, where most of disk material is likely to rapidly accrete onto SMBHs. In warped and torn disks, both the tidal-warp and the tearing radii most strongly depend on the binary semi-major axis, although they also mildly depend on the other orbital and disk parameters. This strong dependence enables us to estimate the semi-major axis, once the tidal warp or tearing radius is determined observationally: for the tidal warp radius of 0.1 pc, the semi-major axis is estimated to be ∼10{sup −2} pc for 10{sup 7} M{sub ⊙} black hole with typical orbital and disk parameters. We also briefly discuss the possibility that central objects of observed warped maser disks in active galactic nuclei are supermassive black hole binaries.« less
Six-axis orthodontic force and moment sensing system for dentist technique training.

PubMed

Midorikawa, Yoshiyuki; Takemura, Hiroshi; Mizoguchi, Hiroshi; Soga, Kohei; Kamimura, Masao; Suga, Kazuhiro; Wei-Jen Lai; Kanno, Zuisei; Uo, Motohiro

2016-08-01

The purpose of this study is to develop a sensing system device that measures three-axis orthodontic forces and three-axis orthodontic moments for dentist training. The developed sensing system is composed of six-axis force sensors, action sticks, sliders, and tooth models. The developed system also simulates various types of tooth row shape patterns in orthodontic operations, and measures a 14 × 6 axis orthodontic force and moment from tooth models simultaneously. The average force and moment error per loaded axis were 2.06 % and 2.00 %, respectively.
DOD Major Automated Information Systems: Improvements Can Be Made in Reporting Critical Changes and Clarifying Leadership Responsibility

DTIC Science & Technology

2016-03-01

The program’s estimated program development cost increased by 45 percent over the original acquisition program baseline due to program scope changes ...DOD MAJOR AUTOMATED INFORMATION SYSTEMS Improvements Can Be Made in Reporting Critical Changes and Clarifying...INFORMATION SYSTEMS Improvements Can Be Made in Reporting Critical Changes and Clarifying Leadership Responsibility Why GAO Did This Study The National
The development and validation of the major life changing decision profile (MLCDP)

PubMed Central

2013-01-01

Background Chronic diseases may influence patients taking major life changing decisions (MLCDs) concerning for example education, career, relationships, having children and retirement. A validated measure is needed to evaluate the impact of chronic diseases on MLCDs, improving assessment of their life-long burden. The aims of this study were to develop a validated questionnaire, the “Major Life Changing Decision Profile” (MLCDP) and to evaluate its psychometric properties. Methods 50 interviews with dermatology patients and 258 questionnaires, completed by cardiology, rheumatology, nephrology, diabetes and respiratory disorder patients, were analysed for qualitative data using Nvivo8 software. Content validation was carried out by a panel of experts. The first version of the MLCDP was completed by 210 patients and an iterative process of multiple Exploratory Factor Analyses and item prevalence was used to guide item reduction. Face validity and practicability was assessed by patients. Results 48 MLCDs were selected from analysis of the transcripts and questionnaires for the first version of the MLCDP, and reduced to 45 by combination of similar themes. There was a high intraclass correlation coefficient (0.7) between the 13 members of the content validation panel. Four more items were deleted leaving a 41-item MLCDP that was completed by 210 patients. The most frequently recorded MLCDs were decisions to change eating habits (71.4%), to change smoking/drinking alcohol habits (58.5%) and not to travel or go for holidays abroad (50.9%). Factor analysis suggested item number reduction from 41 to 34, to 29, then 23 items. However after taking into account item prevalence data as well as factor analysis results, 32 items were retained. The 32-item MLCDP has five domains education (3 items), job/career (9), family/relationships (5), social (10) and physical (5). The MLCDP score is expressed as the absolute number of decisions that have been affected. Conclusions The
The influence of sleep on human hypothalamic-pituitary-adrenal (HPA) axis reactivity: A systematic review.

PubMed

van Dalfsen, Jens H; Markus, C Rob

2018-06-01

Inadequate sleep is highly prevalent and known to decline both physical- and mental health. Literature suggests that altered functioning of the hypothalamic-pituitary-adrenal (HPA) axis might underlie this association. This assumption is mainly based on changes in basal neuroendocrine activity and it is of equal importance to elucidate whether sleep may also influence HPA stress responsiveness. The present review provides a complete outline of recent human studies that have investigated how different aspects of sleep influence cortisol reactivity to laboratory stress. From the available data it can be concluded that both objective and subjective decrements in sleep quality potentiate the stress reactivity of the HPA axis. On the contrary, normal variations in sleep duration do not seem to influence cortisol stress responsiveness whereas excessive daytime sleepiness is associated with a blunting of the cortisol response. Given its well-established health consequences, sensitization of the HPA axis might well be a crucial component linking inadequate sleep to stress-related pathology. Copyright © 2017 Elsevier Ltd. All rights reserved.
Selection for growth rate and body size have altered the expression profiles of somatotropic axis genes in chickens

PubMed Central

Liu, Yong; Xu, Zhiqiang; Duan, Xiaohua; Li, Qihua; Dou, Tengfei; Gu, Dahai; Rong, Hua; Wang, Kun; Li, Zhengtian; Talpur, Mir Zulqarnain; Huang, Ying; Wang, Shanrong; Yan, Shixiong; Tong, Huiquan; Zhao, Sumei; Zhao, Guiping; Su, Zhengchang; Ge, Changrong

2018-01-01

The growth hormone / insulin-like growth factor-1 (GH/IGF-1) pathway of the somatotropic axis is the major controller for growth rate and body size in vertebrates, but the effect of selection on the expression of GH/IGF-1 somatotropic axis genes and their association with body size and growth performance in farm animals is not fully understood. We analyzed a time series of expression profiles of GH/IGF-1 somatotropic axis genes in two chicken breeds, the Daweishan mini chickens and Wuding chickens, and the commercial Avian broilers hybrid exhibiting markedly different body sizes and growth rates. We found that growth rate and feed conversion efficiency in Daweishan mini chickens were significantly lower than those in Wuding chickens and Avian broilers. The Wuding and Daweishan mini chickens showed higher levels of plasma GH, pituitary GH mRNA but lower levels of hepatic growth hormone receptor (GHR) mRNA than in Avian broilers. Daweishan mini chickens showed significantly lower levels of plasma IGF-1, thigh muscle and hepatic IGF-1 mRNA than did Avian broilers and Wuding chickens. These results suggest that the GH part of the somatotropic axis is the main regulator of growth rate, while IGF-1 may regulate both growth rate and body weight. Selection for growth performance and body size have altered the expression profiles of somatotropic axis genes in a breed-, age-, and tissue-specific manner, and manner, and alteration of regulatory mechanisms of these genes might play an important role in the developmental characteristics of chickens. PMID:29630644
Electrocardiographic screening for emphysema: the frontal plane P axis.

PubMed

Baljepally, R; Spodick, D H

1999-03-01

Because the most characteristic and sensitive electrocardiographic (ECG) correlate of pulmonary emphysema in adults is verticalization of the frontal plane P-wave vector (P axis), we investigated its strength as a lone criterion to screen for obstructive pulmonary disease (OPD) in an adult hospital population. In all, 954 consecutive unselected ECGs were required to yield 100 with P axis > or = +70 degrees (unequivocally negative P in a VL during sinus rhythm) and pulmonary function tests. and 100 with P axis < or = +50 degrees (unequivocally positive P-aVL). Obstructive pulmonary disease by both pulmonary function test and clinical criteria was present in 89 of 100 patients with vertical P axes and 4 of 100 patients without OPD. The high sensitivity (89% for this series) and high specificity (96%) makes vertical P axis a useful screening criterion. Its at-a-glance simplicity makes it "user-friendly."
Determining The Plane of The Kuiper Belt with OSSOS

NASA Astrophysics Data System (ADS)

Van Laerhoven, Christa; Kavelaars, J. J.; Volk, Kathryn; Gladman, Brett; Petit, Jean-Marc

2018-04-01

We present the OSSOS-based measurement of the semi-major axes dependent orientation of the Kuiper Belt plane. A Kuiper Belt object's (KBO's) inclination can be broken down into a forced component and a free component. The inclination and longitude of ascending node of the forced inclination define the 'forced plane,' the plane about which the KBO's inclination will precess. Secular theory predicts that this forced plane should depend on semi-major axis. For example, the nu18 secular resonance should create a significant warp in the forced planet near 40.5 au (Chiang and Choi 2008). Not predicted by secular theory is a warp in the distant Kuiper Belt (semi-major axes greater than 50 au) seen by Volk and Malhotra 2016 using KBOs from the Minor Planet Catalog. We investigate what the inclination distribution is for objects beyond Neptune as a function of semi-major axis using the OSSOS characterized sample. Through use of the OSSOS survey simulator we test various underlying orbital distributions and compare how the survey would have observed those populations to the actual observed sample. In particular, we test various widths for the inclination distribution about various local forcing planes for the kernel, stirred, and hot classical Kuiper Belt. We find that the forced plane in matches well with the expected forced plane from secular theory. Through most of the main Kuiper Belt (between the 3:2 and 2:1 resonances), we can reject both the ecliptic plane and the invariable plane as the true forced plane. Only as the expected secularly forced plane approaches the invariable plane does the invariable plane become non-rejectable. In the outer Kuiper Belt we reject the nominal mean-plane measured by Volk and Malhotra, but smaller warps are still allowed by the data.
The changing interface between district hospital cardiology and the major cardiac centres

PubMed Central

1997-01-01

The national priority for reducing mortality and morbidity from cardiovascular disease, the resulting expansion in the number of consultant cardiologists, and the reforms of the National Health Service have produced significant changes in delivery of care for cardiac patients and in the relations between district general hospitals (DGH) and the old regional cardiac centres. 1.2 The British Cardiac Society, the Medical Royal Colleges of Physicians of London and Edinburgh, and the Royal College of Physicians and Surgeons of Glasgow established a working group to make recommendations on the most appropriate evolution of these changes to secure high quality care in a cost-effective and professionally rewarding environment. The principal conclusions of the working group were: i) The establishment of new cardiac catheterisation laboratories in DGHs remote from a major cardiac centre should be encouraged provided the workload is adequate to ensure efficient use of the facility. ii) Cardiologists working in districts close to a major centre should be encouraged to catheterise their patients at the centre. iii) Close liaison of the district cardiologist with a cardiac surgeon and interventionist is vitally important. iv) The centres will be required to provide tertiary care for emergency and urgent cases from their traditional catchment area, specialised expertise for the management of rare and difficult cases, and angioplasty. Some centres will also offer complex electrophysiology, and ablation techniques. v) The centres must also provide routine cardiology services for their local district, facilities for cardiac catheterisation for DGH cardiologists, and training for doctors, nurses, technicians, and radiographers. vi) Some centres will be linked with paediatric cardiology and paediatric cardiac surgical units. vii) District cardiac centres will be required to provide a full non-invasive diagnostic service and emergency care for patients referred by general practitioners
The cortisol awakening response and major depression: examining the evidence

PubMed Central

Dedovic, Katarina; Ngiam, Janice

2015-01-01

A vast body of literature has revealed that dysregulation of the hypothalamic–pituitary–adrenal (HPA) stress axis is associated with etiology of major depressive disorder (MDD). There are many ways that the dysregulation of the HPA axis can be assessed: by sampling diurnal basal secretion and/or in response to a stress task, pharmacological challenge, and awakening. Here, we focus on the association between cortisol awakening response (CAR), as one index of HPA axis function, and MDD, given that the nature of this association is particularly unclear. Indeed, in the following selective review, we attempt to reconcile sometimes-divergent evidence of the role of CAR in the pathway to depression. We first examine association of CAR with psychological factors that have been linked with increased vulnerability to develop depression. Then, we summarize the findings regarding the CAR profile in those with current depression, and evaluate evidence for the role of CAR following depression resolution and continued vulnerability. Finally, we showcase longitudinal studies showing the role of CAR in predicting depression onset and recurrence. Overall, the studies reveal an important, but complex, association between CAR and vulnerability to depression. PMID:25999722
Process for controlling morphology and improving thermal-mechanical performance of high performance interpenetrating and semi-interpenetrating polymer networks

NASA Technical Reports Server (NTRS)

Pater, Ruth H. (Inventor); Hansen, Marion G. (Inventor)

1997-01-01

In the process of the present invention, a non-polar, aprotic solvent is removed from an oligomer/polymer solution by freeze-drying in order to produce IPNs and semi-IPNs. By thermally quenching the solution to a solid in a short length of time, the size of the minor constituent-rich regions is greatly reduced as they are excluded along with the major constituent from the regions of crystallizing solvent. The use of this process sequence of controlling phase morphology provides IPNs and semi-IPNs with improved fracture toughness, microcracking resistance, and other physical-mechanical properties as compared to IPNs and semi-IPNs formed when the solvent is evaporated rather than sublimed.
Gut microbiota-bone axis.

PubMed

Villa, Christopher R; Ward, Wendy E; Comelli, Elena M

2017-05-24

The gut microbiota (GM) is an important regulator of body homeostasis, including intestinal and extra-intestinal effects. This review focuses on the GM-bone axis, which we define as the effect of the gut-associated microbial community or the molecules they synthesize, on bone health. While research in this field is limited, findings from preclinical studies support that gut microbes positively impact bone mineral density and strength parameters. Moreover, administration of beneficial bacteria (probiotics) in preclinical models has demonstrated higher bone mineralization and greater bone strength. The preferential bacterial genus that has shown these beneficial effects in bone is Lactobacillus and thus lactobacilli are among the best candidates for future clinical intervention trials. However, their effectiveness is dependent on stage of development, as early life constitutes an important time for impacting bone health, perhaps via modulation of the GM. In addition, sex-specific difference also impacts the efficacy of the probiotics. Although auspicious, many questions regarding the GM-bone axis require consideration of potential mechanisms; sex-specific efficacy; effective dose of probiotics; and timing and duration of treatment.
Flexible helical-axis stellarator

DOEpatents

Harris, Jeffrey H.; Hender, Timothy C.; Carreras, Benjamin A.; Cantrell, Jack L.; Morris, Robert N.

1988-01-01

An 1=1 helical winding which spirals about a conventional planar, circular central conductor of a helical-axis stellarator adds a significant degree of flexibility by making it possible to control the rotational transform profile and shear of the magnetic fields confining the plasma in a helical-axis stellarator. The toroidal central conductor links a plurality of toroidal field coils which are separately disposed to follow a helical path around the central conductor in phase with the helical path of the 1=1 winding. This coil configuration produces bean-shaped magnetic flux surfaces which rotate around the central circular conductor in the same manner as the toroidal field generating coils. The additional 1=1 winding provides flexible control of the magnetic field generated by the central conductor to prevent the formation of low-order resonances in the rotational transform profile which can produce break-up of the equilibrium magnetic surfaces. Further, this additional winding can deepen the magnetic well which together with the flexible control provides increased stability.
Soil bacterial community responses to revegetation of moving sand dune in semi-arid grassland.

PubMed

Cao, Chengyou; Zhang, Ying; Cui, Zhenbo; Feng, Shuwei; Wang, Tingting; Ren, Qing

2017-08-01

Grasslands in semi-arid Northern China are widely desertified, thus inducing the formation of a large area of moving sand lands. Revegetation of the sandy land is commonly adopted to restore degraded grasslands. The structure of the soil microbial community might dramatically change during degradation and recovery because microorganisms are one of the major drivers of ecological process through their interactions with plants and soil. Assuming that soil properties are the key determinants of the structure of soil bacterial community within the same soil type, whether the vegetation type causes the significant difference in the structure of soil bacterial community during revegetation and restoration of the degraded grasslands remains poorly understood. Our study aimed to (1) investigate the response of soil bacterial communities to the changes during vegetation degradation and recovery and (2) evaluate whether the soil bacterial communities under plantations return to their native state. We detected the shifts in diversities and compositions of the soil bacterial communities and the relative abundance of dominant bacterial taxa by using the high-throughput Illumina MiSeq sequencing technique in an area covered by 32-year-old Caragana microphylla, Artemisia halodendron, Hedysarum fruticosum, Pinus sylvestris var. mongolica, Populus simonii, and Salix gordejevii sand-fixing plantations and in the native community (NC) dominated by elm, and moving sandy dune (MS). We found that the obtained operational taxonomic units by 16S rRNA gene sequencing and diversity index in MS were all significantly lower than those in NC, and the number and composition of dominant genera were significantly different between NC and MS. Interestingly, the compositions of bacterial communities and the dominant genera in different sand-fixation plantations (C. microphylla, A. halodendron, H. fruticosum, P. sylvestris var. mongolica, P. simonii, and S. gordejevii) were all similar to those of

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