Three-dimensional workstation is useful for measuring the correct size of abdominal aortic aneurysm diameters.

PubMed

Ihara, Tsutomu; Komori, Kimihiro; Yamamoto, Kiyohito; Kobayashi, Masayoshi; Banno, Hiroshi; Kodama, Akio

2013-02-01

Abdominal aortic aneurysm diameter is usually measured by the maximum minor-axis diameter on axial computed tomography (CT). However, this "traditional" diameter may underestimate the real size, as the aorta is not always straight and the aneurysm shape is sometimes in the form of an ellipse along the cross section. Therefore, we measured maximum major-axis diameters using a three-dimensional (3D) workstation and compared them with the traditional maximum minor-axis diameters measured using thin-slice axial CT. CT data of 141 AAA patients (with fusiform aneurysms) were stored in a 3D workstation. These thin-slice CT images were reviewed on the 3D workstation to obtain curved multiplanar reconstruction images (CPR images). Using the CPR images, we measured the maximum major-axis and minor-axis diameters on CPR and the angle of the aneurysms to the body axis. The mean traditional maximum minor-axis diameter was 51.2 ± 8.2 mm, whereas the mean maximum major-axis diameter on CPR was 54.7 ± 10.1 mm. Sixty eight patients had a mean aneurysm size of <50 mm when measured by the traditional minor-axis diameter. Among these patients, five (7.4%) had a major-axis diameter >55 mm on CPR. The measurement of the traditional maximum minor-axis diameter of aneurysms is useful in the case of most patients. However, the traditional maximum minor-axis diameter may underestimate the real aneurysmal diameter, particularly in patients with an ellipse-shaped aneurysm. The maximum major-axis diameter as measured using CPR images is effective for representing the real aneurysmal size. Copyright © 2013 Elsevier Inc. All rights reserved.

A Miniature Magnetic-Force-Based Three-Axis AC Magnetic Sensor with Piezoelectric/Vibrational Energy-Harvesting Functions

PubMed Central

Hung, Chiao-Fang; Yeh, Po-Chen; Chung, Tien-Kan

2017-01-01

In this paper, we demonstrate a miniature magnetic-force-based, three-axis, AC magnetic sensor with piezoelectric/vibrational energy-harvesting functions. For magnetic sensing, the sensor employs a magnetic–mechanical–piezoelectric configuration (which uses magnetic force and torque, a compact, single, mechanical mechanism, and the piezoelectric effect) to convert x-axis and y-axis in-plane and z-axis magnetic fields into piezoelectric voltage outputs. Under the x-axis magnetic field (sine-wave, 100 Hz, 0.2–3.2 gauss) and the z-axis magnetic field (sine-wave, 142 Hz, 0.2–3.2 gauss), the voltage output with the sensitivity of the sensor are 1.13–26.15 mV with 8.79 mV/gauss and 1.31–8.92 mV with 2.63 mV/gauss, respectively. In addition, through this configuration, the sensor can harness ambient vibrational energy, i.e., possessing piezoelectric/vibrational energy-harvesting functions. Under x-axis vibration (sine-wave, 100 Hz, 3.5 g) and z-axis vibration (sine-wave, 142 Hz, 3.8 g), the root-mean-square voltage output with power output of the sensor is 439 mV with 0.333 μW and 138 mV with 0.051 μW, respectively. These results show that the sensor, using this configuration, successfully achieves three-axis magnetic field sensing and three-axis vibration energy-harvesting. Due to these features, the three-axis AC magnetic sensor could be an important design reference in order to develop future three-axis AC magnetic sensors, which possess energy-harvesting functions, for practical industrial applications, such as intelligent vehicle/traffic monitoring, processes monitoring, security systems, and so on. PMID:28208693

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.

Proliferation of maize (Zea mays L.) roots in response to localized supply of nitrate

NASA Technical Reports Server (NTRS)

Granato, T. C.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

1989-01-01

Maize (Zea mays L.) plants with two primary nodal root axes were grown for 8 d in flowing nutrient culture with each axis independently supplied with NO3-. Dry matter accumulation by roots was similar whether 1.0 mol m-3 NO3- was supplied to one or both axes. When NO3- was supplied to only one axis, however, accumulation of dry matter within the root system was significantly greater in the axis supplied with NO3-. The increased dry matter accumulation by the +N-treated axis was attributable entirely to increased density and growth of lateral branches and not to a difference in growth of the primary axis. Proliferation of lateral branches for the +N axis was associated with the capacity for in situ reduction and utilization of a portion of the absorbed NO3-, especially in the apical region where lateral primordia are initiated. Although reduced nitrogen was translocated to the -N axis, concentrations in the -N axis remained significantly lower than in the +N axis. The concentration of reduced nitrogen, as well as in vitro NO3- reductase activity, was greater in apical than in more basal regions of the +N axis. The enhanced proliferation of lateral branches in the +N axis was accompanied by an increase in total respiration rate of the axis. Part of the increased respiration was attributable to increased mass of roots. The specific respiration rate (micromoles CO2 evolved per hour per gram root dry weight) was also greater for the +N than for the -N axis. If respiration rate is taken as representative of sink demand, stimulation of initiation and growth of laterals by in situ utilization of a localized exogenous supply of NO3- establishes an increased sink demand through enhanced metabolic activity and the increased partitioning of assimilates to the +N axis responds to the difference in sink demand between +N and -N axes.

Motion perception during variable-radius swing motion in darkness.

PubMed

Rader, A A; Oman, C M; Merfeld, D M

2009-10-01

Using a variable-radius roll swing motion paradigm, we examined the influence of interaural (y-axis) and dorsoventral (z-axis) force modulation on perceived tilt and translation by measuring perception of horizontal translation, roll tilt, and distance from center of rotation (radius) at 0.45 and 0.8 Hz using standard magnitude estimation techniques (primarily verbal reports) in darkness. Results show that motion perception was significantly influenced by both y- and z-axis forces. During constant radius trials, subjects' perceptions of tilt and translation were generally almost veridical. By selectively pairing radius (1.22 and 0.38 m) and frequency (0.45 and 0.8 Hz, respectively), the y-axis acceleration could be tailored in opposition to gravity so that the combined y-axis gravitoinertial force (GIF) variation at the subject's ears was reduced to approximately 0.035 m/s(2) - in effect, the y-axis GIF was "nulled" below putative perceptual threshold levels. With y-axis force nulling, subjects overestimated their tilt angle and underestimated their horizontal translation and radius. For some y-axis nulling trials, a radial linear acceleration at twice the tilt frequency (0.25 m/s(2) at 0.9 Hz, 0.13 m/s(2) at 1.6 Hz) was simultaneously applied to reduce the z-axis force variations caused by centripetal acceleration and by changes in the z-axis component of gravity during tilt. For other trials, the phase of this radial linear acceleration was altered to double the magnitude of the z-axis force variations. z-axis force nulling further increased the perceived tilt angle and further decreased perceived horizontal translation and radius relative to the y-axis nulling trials, while z-axis force doubling had the opposite effect. Subject reports were remarkably geometrically consistent; an observer model-based analysis suggests that perception was influenced by knowledge of swing geometry.

Reliability of frames of reference used for tibial component rotation in total knee arthroplasty.

PubMed

Page, Stephen R; Deakin, Angela H; Payne, Anthony P; Picard, Frederic

2011-01-01

This study evaluated seven different frames of reference used for tibial component rotation in total knee arthroplasty (TKA) to determine which ones showed good reliability between bone specimens. An optoelectronic system based around a computer-assisted surgical navigation system was used to measure and locate 34 individual anatomical landmarks on 40 tibias. Each particular frame of reference was reconstructed from a group of data points taken from the surface of each bone. The transverse axis was used as the baseline to which the other axes were compared, and the differences in angular rotation between the other six reference frames and the transverse axis were calculated. There was high variability in the tibial rotational alignment associated with all frames of reference. Of the references widely used in current TKA procedures, the tibial tuberosity axis and the anterior condylar axis had lower standard deviations (6.1° and 7.3°, respectively) than the transmalleolar axis and the posterior condylar axis (9.3° for both). In conclusion, we found high variability in the frames of reference used for tibial rotation alignment. However, the anterior condylar axis and transverse axis may warrant further tests with the use of navigation. Combining different frames of reference such as the tibial tuberosity axis, anterior condylar axis and transverse axis may reduce the range of errors found in all of these measurements.

Diagnostic assignment of criteria: clinicians and DSM-IV.

PubMed

Linde, J A; Clark, L A

1998-01-01

The study examined clinician matching of diagnostic criteria to selected DSM-IV Axis I and II disorders. A national sample of clinical psychologists and psychiatrists assigned symptom criteria, presented in scrambled order by axis, to DSM-IV diagnoses with which they believed the criteria belonged, without using the DSM. On average, clinicians assigned 69% of Axis I criteria and 75% of Axis II criteria to the designated DSM-IV diagnosis. The Axis II data represent increased agreement over the 66% found for DSM-III-R. Reasons for the increase are discussed, focusing on modifications made in DSM-IV and increased familiarity with personality disorders. The significantly higher rate of agreement for Axis II over Axis I contrasts with typical reliability data which suggests that Axis I disorders are better defined. Specific points of disagreement between clinician criteria assignments and the DSM-IV are discussed.

Dual axis translation apparatus and system for translating an optical beam and related method

DOEpatents

Cassidy, Kelly

1991-01-01

A dual axis translation device and system in accordance with this invention, for translating an optical beam along both an x-axis and a y-axis which are perpendicular to one another, has a beam directing means acting on said optical beam for directing the beam along a particular path transverse to said x and y axes. An arrangement supporting said beam directing means for movement in the x and y direction within a given plane is provided. The arrangement includes a first means for translating said beam directing means along the x-axis in said given plane in order to translate the beam along said x-axis. The arrangement comprises a second means for translating said beam directing means along the y-axis in said given plane in order to translate the beam along said y-axis.

Transverse-displacement stabilizer for passive magnetic bearing systems

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

Post, Richard F

The invention provides a way re-center a rotor's central longitudinal rotational axis with a desired system longitudinal axis. A pair of planar semicircular permanent magnets are pieced together to form a circle. The flux from each magnet is pointed in in opposite directions that are both parallel with the rotational axis. A stationary shorted circular winding the plane of which is perpendicular to the system longitudinal axis and the center of curvature of the circular winding is positioned on the system longitudinal axis. Upon rotation of the rotor, when a transverse displacement of the rotational axis occurs relative to themore » system longitudinal axis, the winding will experience a time-varying magnetic flux such that an alternating current that is proportional to the displacement will flow in the winding. Such time-varying magnetic flux will provide a force that will bring the rotor back to its centered position about the desired axis.« less

Artificial Earth Satellites Designed and Fabricated by The Johns Hopkins University Applied Physics Laboratory. Revised

DTIC Science & Technology

1978-07-01

occurred. The attitude detection system included a three-axis fluxgate vector magnetometer and solar attitude detectors that produced both analog and digital ...heliogoniometer ( digital solar attitudeIsensing system) Three axis analog solar detection - Rubidium vapor magnetometer Three axis fluxgate magnetometer ...Telemetry: 35 channels modulating 150 MHz carrier on command Three axis solar attitude detector system Three axis fluxgate magnetometer system

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

Ridge-crossing mantle plumes and gaps in tracks

NASA Astrophysics Data System (ADS)

Sleep, Norman H.

2002-12-01

Hot spot tracks approach, cross, and leave ridge axes. The complications of this process make it difficult to determine the track followed by a plume and the evolution of its vigor. When a plume is sufficiently near the ridge axis, buoyant plume material flows along the base of the lithosphere toward the axis, forming an on-axis hot spot. The track of the on-axis hot spot is a symmetric V on both plates and an unreliable indication of the path followed by the plume. Aseismic ridges form more or less along flowlines from a plume to a ridge axis when channels form at the base of the lithosphere. A dynamic effect is that off-axis hot spots appear to shut off at the time that an on-axis hot spot becomes active along an axis-approaching track. This produces a gap in the obvious track and a jump of the hot spot to the ridge axis. The gap results from the effects of ponded plume material on intraplate (membrane) stress. Membrane tension lets dikes ascend efficiently to produce obvious tracks of edifices. An off-axis hot spot shuts down when the plume is sufficiently near the ridge axis that plume material flows there, putting the nearby lithosphere above the plume into compression, preventing dikes. In addition, the off-axis thickness of plume material, which produces membrane tension, decreases as the slope of the base of the lithosphere increases beneath young lithosphere. Slow spreading rates favor gaps produced in this way. Gaps are observed near both fast and slow ridges.

The application of image processing in the measurement for three-light-axis parallelity of laser ranger

NASA Astrophysics Data System (ADS)

Wang, Yang; Wang, Qianqian

2008-12-01

When laser ranger is transported or used in field operations, the transmitting axis, receiving axis and aiming axis may be not parallel. The nonparallelism of the three-light-axis will affect the range-measuring ability or make laser ranger not be operated exactly. So testing and adjusting the three-light-axis parallelity in the production and maintenance of laser ranger is important to ensure using laser ranger reliably. The paper proposes a new measurement method using digital image processing based on the comparison of some common measurement methods for the three-light-axis parallelity. It uses large aperture off-axis paraboloid reflector to get the images of laser spot and white light cross line, and then process the images on LabVIEW platform. The center of white light cross line can be achieved by the matching arithmetic in LABVIEW DLL. And the center of laser spot can be achieved by gradation transformation, binarization and area filter in turn. The software system can set CCD, detect the off-axis paraboloid reflector, measure the parallelity of transmitting axis and aiming axis and control the attenuation device. The hardware system selects SAA7111A, a programmable vedio decoding chip, to perform A/D conversion. FIFO (first-in first-out) is selected as buffer.USB bus is used to transmit data to PC. The three-light-axis parallelity can be achieved according to the position bias between them. The device based on this method has been already used. The application proves this method has high precision, speediness and automatization.

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.

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

Psychiatric morbidity in murder and attempted murder crime convicts: a Turkey study.

PubMed

Kugu, N; Akyuz, G; Dogan, O

2008-03-05

In the present, the morbidity of psychiatric disorders of homicide/attempted homicide crime convicts imprisoned in Turkey, Sivas maximum security prison was investigated. Seventy imprisoned homicide/attempted homicide crime convicts included in this study. Sociodemographic information form, structured clinical interview for DSM-IV Axis-I disorders and structured clinical interview for DSM-III-R personality disorders applied to the participants. Most commonly diagnosed disorders among those convicts were current Axis-I disorders, depressive disorders (7.1%) and anxiety disorders (5.7%). Among Axis-I disorders, the most diagnosed one was the substance use disorders (45.7%). The most diagnosed Axis-II disorder was found as to be antisocial personality disorder (48.6%). The rate of convicts who were diagnosed as having both Axis-I and Axis-II disorders was 51.4%. The most prevalently accompanying lifetime Axis-I disorders to antisocial personality disorder with respect to Axis-I, and Axis-II comorbidity was substance use disorders. As a result, it was thought that the substance use disorders and antisocial personality disorder among the homicide/attempted homicide crime convicts were the most prevalent lifetime psychiatric disorders.

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, and erupting more primitive lava compositions. OAMLs at the edges of the CMZ, where it is cooler, feed more evolved off-axis eruptions. Lower magma flux at the edges increases crustal residence time and the extent to which magmas crystallize. OAMLs outside of the CMZ host magmas that may escaped any central mixing and erupt a greater range of compositions.

Fine alignment of a large segmented mirror

NASA Technical Reports Server (NTRS)

Dey, Thomas William (Inventor)

2010-01-01

A system for aligning a segmented mirror includes a source of radiation directed along a first axis to the segmented mirror and a beamsplitter removably inserted along the first axis for redirecting radiation from the first axis to a second axis, substantially perpendicular to the first axis. An imaging array is positioned along the second axis for imaging the redirected radiation, and a knife-edge configured for cutting the redirected radiation is serially positioned to occlude and not occlude the redirected radiation, effectively providing a variable radiation pattern detected by the imaging array for aligning the segmented mirror.

A novel method of measuring spatial rotation angle using MEMS tilt sensors

NASA Astrophysics Data System (ADS)

Cao, Jian'an; Zhu, Xin; Wu, Hao; Zhang, Leping

2017-10-01

This paper presents a novel method of measuring spatial rotation angle with a dual-axis micro-electro-mechanical systems tilt sensor. When the sensor is randomly mounted on the surface of the rotating object, there are three unpredictable and unknown mounting position parameters: α, the sensor’s swing angle on the measuring plane; β, the angle between the rotation axis and the horizontal plane; and γ, the angle between the measuring plane and the rotation axis. Thus, the sensor’s spatial rotation model is established to describe the relationship between the measuring axis, rotation axis, and horizontal plane, and the corresponding analytical equations are derived. Furthermore, to eliminate the deviation caused by the uncertain direction of the rotation axis, an extra perpendicularly mounted, single-axis tilt sensor is combined with the dual-axis tilt sensor, forming a three-axis tilt sensor. Then, by measuring the sensors’ three tilts and solving the model’s equations, the object’s spatial rotation angle is obtained. Finally, experimental results show that the developed tilt sensor is capable of measuring spatial rotation angle in the range of  ±180° with an accuracy of 0.2° if the angle between the rotation axis and the horizontal plane is less than 75°.

[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.

Piezoelectrically pushed rotational micromirrors using detached PZT actuators for wide-angle optical switch applications

NASA Astrophysics Data System (ADS)

Kim, Sung-Jin; Cho, Young-Ho; Nam, Hyo-Jin; Bu, Jong Uk

2008-12-01

This paper presents a torsional micromirror detached from PZT actuators (TMD), whose rotational motion is achieved by push bars in the PZT actuators, detached from the micromirror. The push bar mechanism is intended to reduce the bending, tensile and torsional constraints generated by the conventional bending bar mechanism, where the torsional micromirror is attached to the PZT actuators (TMA). We have designed, fabricated and tested the prototypes of TMDs for single-axis and dual-axis rotations, respectively. The single-axis TMD generates a static rotational angle of 6.1° at 16 Vdc, which is six times larger than that of the single-axis TMA, 0.9°. However, the rotational response curve of TMD shows hysteresis and zero offset due to the static friction from the initial contact force between the cover and the push bar in the PZT actuator. We have shown that 63.2% of the hysteresis is reduced by eliminating the initial contact force of the PZT actuator. The dual-axis TMD generates static rotational angles of 5.5° and 4.7° in the x-axis and y-axis, respectively, at 16 Vdc. The measured resonant frequencies of the dual-axis TMD are 2.1 ± 0.1 kHz in the x-axis and 1.7 ± 0.1 kHz in the y-axis. The dual-axis TMD shows stable operation without severe wear for 21.6 million cycles driven by the 16 Vp-p sinusoidal wave signal at room temperature.

Conical Fourier shell correlation applied to electron tomograms.

PubMed

Diebolder, C A; Faas, F G A; Koster, A J; Koning, R I

2015-05-01

The resolution of electron tomograms is anisotropic due to geometrical constraints during data collection, such as the limited tilt range and single axis tilt series acquisition. Acquisition of dual axis tilt series can decrease these effects. However, in cryo-electron tomography, to limit the electron radiation damage that occurs during imaging, the total dose should not increase and must be fractionated over the two tilt series. Here we set out to determine whether it is beneficial fractionate electron dose for recording dual axis cryo electron tilt series or whether it is better to perform single axis acquisition. To assess the quality of tomographic reconstructions in different directions here we introduce conical Fourier shell correlation (cFSCe/o). Employing cFSCe/o, we compared the resolution isotropy of single-axis and dual-axis (cryo-)electron tomograms using even/odd split data sets. We show that the resolution of dual-axis simulated and cryo-electron tomograms in the plane orthogonal to the electron beam becomes more isotropic compared to single-axis tomograms and high resolution peaks along the tilt axis disappear. cFSCe/o also allowed us to compare different methods for the alignment of dual-axis tomograms. We show that different tomographic reconstruction programs produce different anisotropic resolution in dual axis tomograms. We anticipate that cFSCe/o can also be useful for comparisons of acquisition and reconstruction parameters, and different hardware implementations. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

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/.

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.

Modelling of the Hypothalamic-Pituitary-Adrenal Axis Perturbations by Externally Induced Cholesterol Pulses of Finite Duration and with Asymmetrically Distributed Concentration Profile

NASA Astrophysics Data System (ADS)

Stanojević, A.; Marković, V. M.; Čupić, Ž.; Vukojević, V.; Kolar-Anić, L.

2017-12-01

A model was developed that can be used to study the effect of gradual cholesterol intake by food on the HPA axis dynamics. Namely, well defined oscillatory dynamics of vital neuroendocrine hypothalamic-pituitary-adrenal (HPA) axis has proven to be necessary for maintaining regular basal physiology and formulating appropriate stress response to various types of perturbations. Cholesterol, as a precursor of all steroid HPA axis hormones, can alter the dynamics of HPA axis. To analyse its particular influence on the HPA axis dynamics we used stoichiometric model of HPA axis activity, and simulate cholesterol perturbations in the form of finite duration pulses, with asymmetrically distributed concentration profile. Our numerical simulations showed that there is a complex, nonlinear dependence between the HPA axis responsiveness and different forms of applied cholesterol concentration pulses, indicating the significance of kinetic modelling, and dynamical systems theory for the understanding of large-scale self-regulatory, and homeostatic processes within this neuroendocrine system.

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.

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.

Fused off-axis object illumination direct-to-digital holography with a plurality of illumination sources

DOEpatents

Price, Jeffery R.; Bingham, Philip R.

2005-11-08

Systems and methods are described for rapid acquisition of fused off-axis illumination direct-to-digital holography. A method of recording a plurality of off-axis object illuminated spatially heterodyne holograms, each of the off-axis object illuminated spatially heterodyne holograms including spatially heterodyne fringes for Fourier analysis, includes digitally recording, with a first illumination source of an interferometer, a first off-axis object illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; and digitally recording, with a second illumination source of the interferometer, a second off-axis object illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis.

Proposed MIL Standard and Handbook - Flying Qualities of Air Vehicles. Volume I. Proposed MIL Standard

DTIC Science & Technology

1982-11-01

control 4centering and breakout forces 21 3.2.9.6 Pitch axis control forces- free play 21 3.2.9.7 Pitch axis control force limits 21 3.2.9.7.1 Pitch axis...axis control forces - control centering and breakout forces 31 *3.5.10.5 Roll axis control forces -- free play 31 3.5.10.6 Roll axis control force limits...vs. deflection 3.2.9.5 Control centering and -- no(-) to homin and hOax breakout forces no(*) 3.2.9.6 Free play I 3.2.9.7.1 Force limits -- takeoff

Omni-directional and holonomic rolling platform with decoupled rotational and translational degrees of freedom

DOEpatents

Pin, F.G.; Killough, S.M.

1994-12-20

A wheel assembly includes a support, a cage rotatably mounted on the support and having a longitudinal rotation axis, a first ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis of the cage, and a second ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis or the cage and to the rotation axis of the first ball wheel. A control circuit includes a photodetector signal which indicates ground contact for each ball wheel, and a tachometer which indicates actual drive shaft velocity. 6 figures.

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.

Omni-directional and holonomic rolling platform with decoupled rotational and translational degrees of freedom

DOEpatents

Pin, Francois G.; Killough, Stephen M.

1994-01-01

A wheel assembly includes a support, a cage rotatably mounted on the support and having a longitudinal rotation axis, a first ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis of the cage, and a second ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis or the cage and to the rotation axis of the first ball wheel. A control circuit includes a photodetector signal which indicates ground contact for each ball wheel, and a tachometer which indicates actual drive shaft velocity.

THE LIMITED EFFECT OF COINCIDENT ORIENTATION ON THE CHOICE OF INTRINSIC AXIS (.).

PubMed

Li, Jing; Su, Wei

2015-06-01

The allocentric system computes and represents general object-to-object spatial relationships to provide a spatial frame of reference other than the egocentric system. The intrinsic frame-of-reference system theory, which suggests people learn the locations of objects based upon an intrinsic axis, is important in research about the allocentric system. The purpose of the current study was to determine whether the effect of coincident orientation on the choice of intrinsic axis was limited. Two groups of participants (24 men, 24 women; M age = 24 yr., SD = 2) encoded different spatial layouts in which the objects shared the coincident orientation of 315° and 225° separately at learning perspective (0°). The response pattern of partial-scene-recognition task following learning reflected different strategies for choosing the intrinsic axis under different conditions. Under the 315° object-orientation condition, the objects' coincident orientation was as important as the symmetric axis in the choice of the intrinsic axis. However, participants were more likely to choose the symmetric axis as the intrinsic axis under the 225° object-orientation condition. The results suggest the effect of coincident orientation on the choice of intrinsic axis is limited.

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.

Calculating the axes of rotation for the subtalar and talocrural joints using 3D bone reconstructions.

PubMed

Parr, W C H; Chatterjee, H J; Soligo, C

2012-04-05

Orientation of the subtalar joint axis dictates inversion and eversion movements of the foot and has been the focus of evolutionary and clinical studies for a number of years. Previous studies have measured the subtalar joint axis against the axis of the whole foot, the talocrural joint axis and, recently, the principal axes of the talus. The present study introduces a new method for estimating average joint axes from 3D reconstructions of bones and applies the method to the talus to calculate the subtalar and talocrural joint axes. The study also assesses the validity of the principal axes as a reference coordinate system against which to measure the subtalar joint axis. In order to define the angle of the subtalar joint axis relative to that of another axis in the talus, we suggest measuring the subtalar joint axis against the talocrural joint axis. We present corresponding 3D vector angles calculated from a modern human skeletal sample. This method is applicable to virtual 3D models acquired through surface-scanning of disarticulated 'dry' osteological samples, as well as to 3D models created from CT or MRI scans. Copyright © 2012 Elsevier Ltd. All rights reserved.

Properties of perpendicular-anisotropy magnetic tunnel junctions fabricated over the bottom electrode contact

NASA Astrophysics Data System (ADS)

Miura, Sadahiko; Honjo, Hiroaki; Kinoshita, Keizo; Tokutome, Keiichi; Koike, Hiroaki; Ikeda, Shoji; Endoh, Tetsuo; Ohno, Hideo

2015-04-01

Perpendicular-anisotropy magnetic tunnel junctions (MTJs) were prepared on four substrate geometries, i.e., directly on the axis of the bottom electrode contact, directly off the axis of the bottom electrode contact, on the axis of the bottom electrode contact with a polished bottom electrode, and off the axis of the bottom electrode contact with a polished bottom electrode. Electrical shorts were observed for direct on-axis geometry at a certain extent, whereas there were no electrical shorts for the other three geometries. The MR ratio/σR, JC0, and thermal stability factor of the devices for polish on-axis geometry were almost the same as those for polish off-axis geometry. From TEM observations of the polish on-axis device, the interface between the bottom contact and the base electrode was determined to be rough, whereas the MgO barrier layer was determined to be smooth, indicating that the polish process was effective for smooth magnetic tunnel junction fabrication over the bottom contact. MTJs for polish on-axis geometry eliminated the base electrode resistance and increased the magnetoresistance ratio. This technology contributes to the higher density of spin transfer torque magnetic random access memory.

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.

Wide acceptance angle, high concentration ratio, optical collector

NASA Technical Reports Server (NTRS)

Kruer, Mark Arthur (Inventor)

1990-01-01

The invention is directed to an optical collector requiring a wide acceptance angle, and a high concentration ratio. The invention is particularly adapted for use in solar collectors of cassegrain design. The optical collector system includes a parabolic circular concave primary mirror and a hyperbolic circular convex secondary mirror. The primary mirror includes a circular hole located at its center wherein a solar collector is located. The mirrored surface of the secondary mirror has three distinct zones: a center circle, an on-axis annulus, and an off-axis section. The parabolic shape of the primary mirror is chosen so that the primary mirror reflects light entering the system on-axis onto the on-axis annulus. A substantial amount of light entering the system off-axis is reflected by the primary mirror onto either the off-axis section or onto the center circle. Subsequently, the off-axis sections reflect the off-axis light toward the solar collector. Thus, off-axis light is captured which would otherwise be lost to the system. The novelty of the system appears to lie in the configuration of the primary mirror which focuses off-axis light onto an annular portion of the secondary mirror to enable capture thereof. This feature results in wide acceptance angle and a high concentration ratio, and also compensates for the effects of non-specular reflection, and enables a cassegrain configuration to be used where such characteristics are required.

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.

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.

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.

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).

High-speed volume measurement system

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

Lane, Michael H.; Doyle, Jr., James L.; Brinkman, Michael J.

2018-01-30

Disclosed is a volume sensor having a first axis, a second axis, and a third axis, each axis including a laser source configured to emit a beam; a parallel beam generating assembly configured to receive the beam and split the beam into a first parallel beam and a second parallel beam, a beam-collimating assembly configured to receive the first parallel beam and the second parallel beam and output a first beam sheet and a second beam sheet, the first beam sheet and the second beam sheet being configured to traverse the object aperture; a first collecting lens and a secondmore » collecting lens; and a first photodetector and a second photodetector, the first photodetector and the second photodetector configured to output an electrical signal proportional to the object; wherein the first axis, the second axis, and the third axis are arranged at an angular offset with respect to each other.« less

Long range laser traversing system

NASA Technical Reports Server (NTRS)

Caudill, L. O. (Inventor)

1974-01-01

The relative azimuth bearing between first and second spaced terrestrial points which may be obscured from each other by intervening terrain is measured by placing at one of the points a laser source for projecting a collimated beam upwardly in the vertical plane. The collimated laser beam is detected at the second point by positioning the optical axis of a receiving instrument for the laser beam in such a manner that the beam intercepts the optical axis. In response to the optical axis intercepting the beam, the beam is deflected into two different ray paths by a beam splitter having an apex located on the optical axis. The energy in the ray paths is detected by separate photoresponsive elements that drive logic networks for proving indications of: (1) the optical axis intercepting the beam; (2) the beam being on the left of the optical axis and (3) the beam being on the right side of the optical axis.

Adolescent Survivors of Hurricane Katrina: A Pilot Study of Hypothalamic-Pituitary-Adrenal Axis Functioning

ERIC Educational Resources Information Center

Pfefferbaum, Betty; Tucker, Phebe; Nitiéma, Pascal

2015-01-01

Background: The hypothalamic-pituitary-adrenal (HPA) axis constitutes an important biological component of the stress response commonly studied through the measurement of cortisol. Limited research has examined HPA axis dysregulation in youth exposed to disasters. Objective: This study examined HPA axis activation in adolescent Hurricane Katrina…

Cloverleaf microgyroscope with electrostatic alignment and tuning

NASA Technical Reports Server (NTRS)

Challoner, A. Dorian (Inventor); Gutierrez, Roman C. (Inventor); Tang, Tony K. (Inventor)

2007-01-01

A micro-gyroscope (10) having closed loop output operation by a control voltage (V.sub.ty), that is demodulated by a drive axis (x-axis) signal V.sub.thx of the sense electrodes (S1, S2), providing Coriolis torque rebalance to prevent displacement of the micro-gyroscope (10) on the output axis (y-axis) V.sub.thy.about.0. Closed loop drive axis torque, V.sub.tx maintains a constant drive axis amplitude signal, V.sub.thx. The present invention provides independent alignment and tuning of the micro-gyroscope by using separate electrodes and electrostatic bias voltages to adjust alignment and tuning. A quadrature amplitude signal, or cross-axis transfer function peak amplitude is used to detect misalignment that is corrected to zero by an electrostatic bias voltage adjustment. The cross-axis transfer function is either V.sub.thy/V.sub.ty or V.sub.tnx/V.sub.tx. A quadrature signal noise level, or difference in natural frequencies estimated from measurements of the transfer functions is used to detect residual mistuning, that is corrected to zero by a second electrostatic bias voltage adjustment.

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.

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.

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.

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.

Polarization/Spatial Combining of Laser-Diode Pump Beams

NASA Technical Reports Server (NTRS)

Gelsinger, Paul; Liu, Duncan

2008-01-01

A breadboard version of an optical beam combiner is depicted which make it possible to use the outputs of any or all of four multimode laser diodes to pump a non-planar ring oscillator (NPRO) laser. The output of each laser diode has a single-mode profile in the meridional plane containing an axis denoted the 'fast' axis and a narrower multimode profile in the orthogonal meridional plane, which contains an axis denoted the 'slow' axis and a narrower multimode profile in the orthogonal meridional plane, which contains an axis denoted the 'slow' axis. One of the purposes served by the beam-combining optics is to reduce the fast-axis numerical aperture (NA) of the laser-diode output to match the NA of the optical fiber. Along the slow axis, the unmodified laser-diode NA is already well matched to the fiber optic NA, so no further slow-axis beam shaping is needed. In this beam combiner, the laser-diode outputs are collimated by aspherical lenses, then half-wave plates and polarizing beam splitters are used to combine the four collimated beams into two beams. Spatial combination of the two beams and coupling into the optical fiber is effected by use of anamorphic prisms, mirrors, and a focusing lens. The anamorphic prisms are critical elements in the NA-matching scheme, in that they reduce the fast-axis beam width to 1/6 of its original values. Inasmuch as no slow-axis beam shaping is needed, the collimating and focusing lenses are matched for 1:1 iumaging. Because these lenses are well corrected for infinite conjugates the combiner offers diffraction-limited performance along both the fast and slow axes.

Sensitivity of finite helical axis parameters to temporally varying realistic motion utilizing an idealized knee model.

PubMed

Johnson, T S; Andriacchi, T P; Erdman, A G

2004-01-01

Various uses of the screw or helical axis have previously been reported in the literature in an attempt to quantify the complex displacements and coupled rotations of in vivo human knee kinematics. Multiple methods have been used by previous authors to calculate the axis parameters, and it has been theorized that the mathematical stability and accuracy of the finite helical axis (FHA) is highly dependent on experimental variability and rotation increment spacing between axis calculations. Previous research has not addressed the sensitivity of the FHA for true in vivo data collection, as required for gait laboratory analysis. This research presents a controlled series of experiments simulating continuous data collection as utilized in gait analysis to investigate the sensitivity of the three-dimensional finite screw axis parameters of rotation, displacement, orientation and location with regard to time step increment spacing, utilizing two different methods for spatial location. Six-degree-of-freedom motion parameters are measured for an idealized rigid body knee model that is constrained to a planar motion profile for the purposes of error analysis. The kinematic data are collected using a multicamera optoelectronic system combined with an error minimization algorithm known as the point cluster method. Rotation about the screw axis is seen to be repeatable, accurate and time step increment insensitive. Displacement along the axis is highly dependent on time step increment sizing, with smaller rotation angles between calculations producing more accuracy. Orientation of the axis in space is accurate with only a slight filtering effect noticed during motion reversal. Locating the screw axis by a projected point onto the screw axis from the mid-point of the finite displacement is found to be less sensitive to motion reversal than finding the intersection of the axis with a reference plane. A filtering effect of the spatial location parameters was noted for larger time step increments during periods of little or no rotation.

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 exciter and the dither mechanical frequencies, the misalignment may be too small to be detected, otherwise, the amplitude of the sum and difference frequencies will show the misalignment angle between the gyro angle rate input axis and the dither axis. Finally, some related parameters such as frequency and amplitude of the angle exciter and sample rate are calculated and the results are analyzed. The simulation and experiment result prove the effectiveness of the proposed method..

76 FR 23838 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Open Axis Group...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-28

... Production Act of 1993--Open Axis Group, Inc. Notice is hereby given that, on March 22, 2011, pursuant to.... (``the Act''), Open Axis Group, Inc. (``Open Axis'') has filed written notifications simultaneously with..., Ontario, CANADA; and OpenJaw Technologies Ltd., Dublin, IRELAND, have been added as parties to this...

76 FR 39902 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Open Axis Group...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-07

... Production Act of 1993--Open Axis Group, Inc. Notice is hereby given that, on May 31, 2011, pursuant to.... (``the Act''), Open Axis Group, Inc. (``Open Axis'') has filed written notifications simultaneously with... planned activity of the group research project. Membership in this group research project remains open...

Transition duct with late injection in turbine system

DOEpatents

LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray; Flanagan, James Scott; Kim, Won -Wook; McMahan, Kevin Weston

2015-09-15

A system for supplying an injection fluid to a combustor is disclosed. The system includes a transition duct comprising an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The passage defines a combustion chamber. The system further includes a tube providing fluid communication for the injection fluid to flow through the transition duct and into the combustion chamber.

A magnetic-piezoelectric smart material-structure sensing three axis DC and AC magnetic-fields

NASA Astrophysics Data System (ADS)

Hung, Chiao-Fang; Chen, Chin-Chung; Yeh, Po-Chen; Chen, Po-Wen; Chung, Tien-Kan

2017-12-01

In this paper, we demonstrate a smart material-structure can sense not only three-axis AC magnetic-fields but also three-axis DC magnetic-fields. Under x-axis and z-axis AC magnetic field ranging from 0.2 to 3.2 gauss, sensing sensitivity of the smart material-structure stimulated at resonant frequency is approximate 8.79 and 2.80 mV/gauss, respectively. In addition, under x-axis and z-axis DC magnetic fields ranging from 2 to 12 gauss, the sensitivity of the smart material-structure is 1.24-1.54 and 1.25-1.41 mV/gauss, respectively. In addition, under x-axis and z-axis DC magnetic fields ranging from 12 to 20 gauss, the sensitivity of the smart material-structure is 5.17-6.2 and 3.97-4.57 mV/gauss, respectively. These experimental results show that the smart material-structure successfully achieves three-axis DC and AC magnetic sensing as we designed. Furthermore, we also compare the results of the AC and DC magnetic-field sensing to investigate discrepancies. Finally, when applying composite magnetic-fields to the smart material-structure, the smart material-structure shows decent outputs as expected (consistent to the sensing principle). In the future, we believe the smart material-structure capable of sensing AC and DC magnetic fields will have more applications than conventional structures capable of sensing only DC or AC magnetic field. Thus, the smart material-structure will be an important design reference for future magnetic-field sensing technologies.

Smart and precise alignment of optical systems

NASA Astrophysics Data System (ADS)

Langehanenberg, Patrik; Heinisch, Josef; Stickler, Daniel

2013-09-01

For the assembly of any kind of optical systems the precise centration of every single element is of particular importance. Classically the precise alignment of optical components is based on the precise centering of all components to an external axis (usually a high-precision rotary spindle axis). Main drawback of this timeconsuming process is that it is significantly sensitive to misalignments of the reference (e.g. the housing) axis. In order to facilitate process in this contribution we present a novel alignment strategy for the TRIOPTICS OptiCentric® instrument family that directly aligns two elements with respect to each other by measuring the first element's axis and using this axis as alignment reference without the detour of considering an external reference. According to the optical design any axis in the system can be chosen as target axis. In case of the alignment to a barrel this axis is measured by using a distance sensor (e.g., the classically used dial indicator). Instead of fine alignment the obtained data is used for the calculation of its orientation within the setup. Alternatively, the axis of an optical element (single lens or group of lenses) whose orientation is measured with the standard OptiCentric MultiLens concept can be used as a reference. In the instrument's software the decentering of the adjusting element to the calculated axis is displayed in realtime and indicated by a target mark that can be used for the manual alignment. In addition, the obtained information can also be applied for active and fully automated alignment of lens assemblies with the help of motorized actuators.

Assessment and validation of CT scanogram to compare per-operative and post-operative mechanical axis after navigated total knee replacement

PubMed Central

Jain, Sunil

2008-01-01

Our objective was to assess and validate low-dose computed tomography (CT) scanogram as a post-operative imaging modality to measure the mechanical axis after navigated total knee replacement. A prospective study was performed to compare intra-operative and post-operative mechanical axis after navigated total knee replacements. All consecutive patients who underwent navigated total knee replacement between May and December 2006 were included. The intra-operative final axis was recorded, and post-operatively a CT scanogram of lower limbs was performed. The mechanical axis was measured and compared against the intra-operative measurement. There were 15 patients ranging in age from 57 to 80 (average 70) years. The average final intra-operative axis was 0.56° varus (4° varus to 1.5° valgus) and post-operative CT scanogram axis was 0.52° varus (3.1° varus to 1.8° valgus). The average deviation from final axes to CT scanogram axes was 0.12° valgus with a correlation coefficient of 0.9. Our study suggests that CT scanogram is an imaging modality with reasonable accuracy for measuring mechanical axis despite significantly low radiation. It also confirms a high level of correlation between intra-operative and post-operative mechanical axis after navigated total knee replacement. PMID:18696064

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

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.

Determinants of the epithelial-muscular axis on embryonic stem cell-derived gut-like structures.

PubMed

Luo, Yi; Takaki, Miyako; Misawa, Hiromi; Matsuyoshi, Hiroko; Sasahira, Tomonori; Chihara, Yoshitomo; Fujii, Kiyomu; Ohmori, Hitoshi; Kuniyasu, Hiroki

2010-01-01

Dome-like structures with epithelial-muscular layers resembling the gut have been derived from mouse embryonic stem (ES) cells. These domes have been reported to show spontaneous contractions and are called ES gut. In the present study, we examined the epithelial-muscular axis of these domes by detecting differentiation markers. A normal epithelial-muscular axis was exhibited in the domes with spontaneous motility, whereas the domes without spontaneous motility showed either an inverted or obscure axis. To investigate the factors affecting the epithelial-muscular axis, we examined the expression of hedgehog signaling factors in the domes. Expression of hedgehog family factors was detected in the epithelial components of the domes with motility, whereas this expression was inverted or obscure in the domes without motility. Out of the 25 domes, 10 of the 10 motility (+) domes showed a normal epithelial-muscular axis, whereas 14 of the 15 motility (-) domes lacked a normal epithelial-muscular axis. This implies that activin A upregulated the expression of sonic hedgehog and intestinal alkaline phosphatase in the embryoid bodies. These findings suggest that the motility of the ES gut depends on the domes' epithelial-muscular axis. Copyright © 2010 S. Karger AG, Basel.

Functional Implications of the IL-23/IL-17 Immune Axis in Schizophrenia.

PubMed

Debnath, Monojit; Berk, Michael

2017-12-01

The aetiology of schizophrenia seems to stem from complex interactions amongst environmental, genetic, metabolic, immunologic and oxidative components. Chronic low-grade inflammation has been persistently linked to schizophrenia, and this has primarily been based on the findings derived from Th1/Th2 cytokine balance. While the IL-23/IL-17 axis plays crucial role in the pathogenesis of several immune-mediated disorders, it has remained relatively unexplored in neuropsychiatric disorders. Altered levels of cytokines related to IL-23/IL-17 axis have been observed in schizophrenia patients in a few studies. In addition, other indirect factors known to confer schizophrenia risk like complement activation and altered gut microbiota are shown to modulate the IL-23/IL-17 axis. These preliminary observations provide crucial clues about the functional implications of IL-23/IL-17 axis in schizophrenia. In this review, an attempt has been made to highlight the biology of IL-23/IL-17 axis and its relevance to schizophrenia risk and pathogenesis. Given the pathogenic potential of the IL-23/IL-17 axis, therapeutic targeting of this axis may be a promising approach to benefit patients suffering from this devastating disorder.

Simulation study of MEMS piezoelectric vibration energy harvester based on c-axis tilted AlN thin film for performance improvement

NASA Astrophysics Data System (ADS)

Kong, Lingfeng; Zhang, Jinhui; Wang, Huiyuan; Ma, Shenglin; Li, Fang; Wang, Qing-Ming; Qin, Lifeng

2016-12-01

In this paper, a MEMS piezoelectric cantilevered vibration energy harvester based on c-axis tilted AlN thin film is investigated. Based on basic piezoelectric equations and static analysis of cantilever beam, the equations for generated energy (E) and open circuit voltage (Vo) were derived, and simulations were carried out to study the effects of geometry parameters and c-axis tilted angle. Results show that E and Vo of energy harvesters are greatly dependent on c-axis tilted angle and geometry parameters, while the coupling between c-axis tilted angle and geometry parameters is not strong. For a given structure size, E and Vo can be almost simultaneously improved by controlling c-axis tilted angle; compared with the case of normal c-axis angle, E with optimal c-axis tilted angle can be amplified by more than 3 times, and the Vo is amplified by about 2 times. E or Vo could be further improved by geometry parameters, while there is trade-off between them. These results can be used for the design and application of piezoelectric cantilevered vibration energy harvester.

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.

Psychiatric comorbidity may not predict suicide during and after hospitalization. A nested case-control study with blinded raters.

PubMed

Walby, Fredrik A; Odegaard, Erik; Mehlum, Lars

2006-06-01

To investigate the differential impact of DSM-IV axis-I and axis-II disorders on completed suicide and to study if psychiatric comorbidity increases the risk of suicide in currently and previously hospitalized psychiatric patients. A nested case-control design based on case notes from 136 suicides and 166 matched controls. All cases and controls were rediagnosed using the SCID-CV for axis-I and the DSM-IV criteria for axis-II disorders and the inter-rater reliability was satisfactory. Raters were blind to the case and control status and the original hospital diagnoses. Depressive disorders and bipolar disorders were associated with an increased risk of suicide. No such effect was found for comorbidity between axis-I disorders and for comorbidity between axis-I and axis-II disorders. Psychiatric diagnoses, although made using a structured and criteria-based approach, was based on information recorded in case notes. Axis-II comorbidity could only be investigated at an aggregated level. Psychiatric comorbidity did not predict suicide in this sample. Mood disorders did, however, increase the risk significantly independent of history of previous suicide attempts. Both findings can inform identification and treatment of patients at high risk for completed suicide.

Formulation of cosmic-ray solar daily variation and its seasonal variation, produced from generalized stationary anisotropy of solar origin

NASA Technical Reports Server (NTRS)

Tatsuoka, R.; Nagashima, K.

1985-01-01

In previous papers, a formulation was presented of cosmic ray daily variations produced from solar anisotropies stationary through a year, and also of their annual (or seasonal) modulation caused by the annual variation of the rotation axis of the Earth relative to that of the Sun. These anisotropies are symmetric for an arbitrary rotation around an axis. From observations of the tri-diurnal variation, it has been suggested that solar anisotropies also contain some axis-asymmetric term of the third order with respect to the IMF-axis. This suggestion has recently found support in a theoretical study by Munakata and Nagashima. According to their results, the terms of axis-asymmetry with respect to IMF-axis appear also in the 2nd order anisotropy, together with some different kinds of axis-symmetric terms. The contribution of these anisotropies to the daily variation is different from that of those discussed previously. The above mentioned formulation is extended to a case of a generalized anisotropy.

Evaluation of conformal and body-axis attitude information for spatial awareness

NASA Astrophysics Data System (ADS)

Jones, Denise R.; Abbott, Terence S.; Burley, James R., II

1992-10-01

The traditional head-up display (HUD) used in most modern fighter aircraft presents attitude information that is both conformal to the outside world and aligned with the body-axis of the aircraft. The introduction of helmet-mounted display (HMD) technology into simulated and actual flight environments has introduced an interesting issue regarding the presentation of attitude information. This information can be presented conformally or relative to the aircraft's body-axis, but not both (except in the special case where the pilot's line of sight is directly matched with the aircraft's body-axis). The question addressed with this study was whether attitude information displayed in an HMD should be presented with respect to the real world (conformally) or to the aircraft's body-axis. To answer this, both conformal and body-axis attitude symbology were compared under simulated air combat situations. The results of this study indicated that the body-axis concept was a more effective HMD display. A detailed description of the flight task and results of this study will be presented.

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.

Radiation modelling and performance evaluations of fixed, single- and double-axis tracking surfaces: a case study for Dhahran city, Saudi Arabia

NASA Astrophysics Data System (ADS)

Abdulsalam, Alrowashed; Idris, Azni Bin; Ahmad, Thamer; Ahsan, Amimul

2017-01-01

This work overviews the solar radiation basics and insolation of different surfaces is presented. A complete solar radiation modelling and investigation on the effect of horizontal plate, yearly tilt, monthly tilt, and single-axis and double-axis tracking surface on the insolation are carried out to conduct performance evaluation using the case study in Dhahran city of Saudi Arabia. The increments received by insolation for the yearly tilt, monthly tilt, and single-axis and dual-axis tracking surface with respect to traditional flat-plate collector is estimated. The results show that the yearly optimal tilt angle due to the south is close to the 0.913 time latitude of Dhahran. It is found that the yearly irradiation gains using yearly and monthly optimal tilts relative to flat panel installation are 7% and 14%, respectively. The yearly insulation gains made by single-axis and dual-axis continuous tracking surfaces are 33% and 48%, respectively.

Evaluation of conformal and body-axis attitude information for spatial awareness

NASA Technical Reports Server (NTRS)

Jones, Denise R.; Abbott, Terence S.; Burley, James R., II

1992-01-01

The traditional head-up display (HUD) used in most modern fighter aircraft presents attitude information that is both conformal to the outside world and aligned with the body-axis of the aircraft. The introduction of helmet-mounted display (HMD) technology into simulated and actual flight environments has introduced an interesting issue regarding the presentation of attitude information. This information can be presented conformally or relative to the aircraft's body-axis, but not both (except in the special case where the pilot's line of sight is directly matched with the aircraft's body-axis). The question addressed with this study was whether attitude information displayed in an HMD should be presented with respect to the real world (conformally) or to the aircraft's body-axis. To answer this, both conformal and body-axis attitude symbology were compared under simulated air combat situations. The results of this study indicated that the body-axis concept was a more effective HMD display. A detailed description of the flight task and results of this study will be presented.

Grating tuned unstable resonator laser cavity

DOEpatents

Johnson, Larry C.

1982-01-01

An unstable resonator to be used in high power, narrow line CO.sub.2 pump lasers comprises an array of four reflectors in a ring configuration wherein spherical and planar wavefronts are separated from each other along separate optical paths and only the planar wavefronts are impinged on a plane grating for line tuning. The reflector array comprises a concave mirror for reflecting incident spherical waves as plane waves along an output axis to form an output beam. A plane grating on the output axis is oriented to reflect a portion of the output beam off axis onto a planar relay mirror spaced apart from the output axis in proximity to the concave mirror. The relay mirror reflects plane waves from the grating to impinge on a convex expanding mirror spaced apart from the output axis in proximity to the grating. The expanding mirror reflects the incident planar waves as spherical waves to illuminate the concave mirror. Tuning is provided by rotating the plane grating about an axis normal to the output axis.

Concepts for conformal and body-axis attitude information for spatial awareness presented in a helmet-mounted display

NASA Technical Reports Server (NTRS)

Jones, Denise R.; Abbott, Terence S.; Burley, James R., II

1993-01-01

A piloted simulation study has been conducted to evaluate two methods of presenting attitude information in a helmet-mounted display (HMD) for spatial awareness in a fighter airplane. One method, the body-axis concept, displayed the information relative to the body axis of the airplane. The quantitative results of this study favored the body-axis concept. Although no statistically significant differences were noted for either the pilots' understanding of roll attitude or target position, the pilots made pitch judgment errors three times more often with the conformal display. The subjective results showed the body-axis display did not cause attitude confusion, a prior concern with this display. In the posttest comments, the pilots overwhelmingly selected the body-axis display as the display of choice.

Apparatus for checking dimensions of workpieces

DOEpatents

Possati, Mario; Golinelli, Guido

1992-01-01

An apparatus for checking features of workpieces with rotational symmetry defining a geometrical axis, which includes a base, rest devices fixed to the base for supporting the workpiece with the geometrical axis horizontally arranged, and a support structure coupled to the base for rotation about a horizontal axis. A counterweight and sensor are coupled to the support structure and movable with the support structure from a rest position, allowing loading of the workpiece to be checked onto the rest devices to a working position where the sensor is brought into cooperation with the workpiece. The axis of rotation of the support structure is arranged below the axis of the workpiece, in correspondence to a vertical geometrical plane passing through the workpiece geometric axis when the workpiece is positioned on the rest devices.

Repeatability and oblique flow response characteristics of current meters

USGS Publications Warehouse

Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.; ,

1993-01-01

Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement of point velocities in streams and rivers were tested. Meters were tested for repeatability and response to oblique flows. Both horizontal- and vertical-axis meters were found to under- and over-register oblique flows with errors generally increasing as the velocity and angle of flow increased. For the oblique flow tests, magnitude of errors were smallest for horizontal-axis meters. Repeatability of all meters tested was good, with the horizontal- and vertical-axis meters performing similarly.

Axisymmetric Optical Membrane Modeling Based on Experimental Results

DTIC Science & Technology

2004-03-01

polymers; one such was NASA’s Inflatable Antenna Experiment (IAE), which is a pressurized lenticular about 14 meters in diameter. It was designed...2cos2θ Astigmatism with axis at +/- 45 deg 5 ρ 2sin2θ Astigmatism with axis at +/- 0 or 90 deg 6 (3 ρ 2-2) ρ cosθ Primary coma along y axis...7 (3 ρ 2-2) ρ sinθ Primary coma along x axis 51 8 6 ρ 4-6 ρ 2+1 Primary spherical aberration 9 ρ 3cos(3θ ) Triangular astigmatism , base on y axis

Leaf seal for transition duct in turbine system

DOEpatents

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

2013-06-11

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a leaf seal contacting the interface member to provide a seal between the interface member and the turbine section.

Piezoelectric actuated gimbal

DOEpatents

Tschaggeny, Charles W [Woods Cross, UT; Jones, Warren F [Idaho Falls, ID; Bamberg, Eberhard [Salt Lake City, UT

2011-09-13

A gimbal is described and which includes a fixed base member defining an axis of rotation; a second member concentrically oriented relative to the axis of rotation; a linear actuator oriented in immediate, adjoining force transmitting relation relative to the base member or to the second member, and which applies force along a linear axis which is tangential to the axis of rotation so as to cause the second member to rotate coaxially relative to the fixed base member; and an object of interest mounted to the second member such that the object of interest is selectively moved relative to the base member about the axis of rotation.

Orientation of human optokinetic nystagmus to gravity: a model-based approach

NASA Technical Reports Server (NTRS)

Gizzi, M.; Raphan, T.; Rudolph, S.; Cohen, B.

1994-01-01

Optokinetic nystagmus (OKN) was induced by having subjects watch a moving display in a binocular, head-fixed apparatus. The display was composed of 3.3 degrees stripes moving at 35 degrees/s for 45 s. It subtended 88 degrees horizontally by 72 degrees vertically of the central visual field and could be oriented to rotate about axes that were upright or tilted 45 degrees or 90 degrees. The head was held upright or was tilted 45 degrees left or right on the body during stimulation. Head-horizontal (yaw axis) and head-vertical (pitch axis) components of OKN were recorded with electro-oculography (EOG). Slow phase velocity vectors were determined and compared with the axis of stimulation and the spatial vertical (gravity axis). With the head upright, the axis of eye rotation during yaw axis OKN was coincident with the stimulus axis and the spatial vertical. With the head tilted, a significant vertical component of eye velocity appeared during yaw axis stimulation. As a result the axis of eye rotation shifted from the stimulus axis toward the spatial vertical. Vertical components developed within 1-2 s of stimulus onset and persisted until the end of stimulation. In the six subjects there was a mean shift of the axis of eye rotation during yaw axis stimulation of approximately 18 degrees with the head tilted 45 degrees on the body. Oblique optokinetic stimulation with the head upright was associated with a mean shift of the axis of eye rotation toward the spatial vertical of 9.2 degrees. When the head was tilted and the same oblique stimulation was given, the axis of eye rotation rotated to the other side of the spatial vertical by 5.4 degrees. This counterrotation of the axis of eye rotation is similar to the "Muller (E) effect," in which the perception of the upright is counterrotated to the opposite side of the spatial vertical when subjects are tilted in darkness. The data were simulated by a model of OKN with a "direct" and "indirect" pathway. It was assumed that the direct visual pathway is oriented in a body, not a spatial frame of reference. Despite the short optokinetic after-nystagmus time constants, strong horizontal to vertical cross-coupling could be produced if the horizontal and vertical time constants were in proper ratio and there were no suppression of nystagmus in directions orthogonal to the stimulus direction. The model demonstrates that the spatial orientation of OKN can be achieved by restructuring the system matrix of velocity storage. We conclude that an important function of velocity storage is to orient slow-phase velocity toward the spatial vertical during movement in a terrestrial environment.

Hybrid Modes in Long Wavelength Free Electron Lasers

DTIC Science & Technology

2010-12-01

response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and...diffraction along one axis, allowing free space diffraction along the other axis. We continue the analysis of the relativistic electron beam, co-propagating...control diffraction along one axis, allowing free space diffraction along the other axis. We continue the analysis of the relativistic electron beam, co

Adaptive PI control strategy for flat permanent magnet linear synchronous motor vibration suppression

NASA Astrophysics Data System (ADS)

Meng, Fanwei; Liu, Chengying; Li, Zhijun; Wang, Liping

2013-01-01

Due to low damping ratio, flat permanent magnet linear synchronous motor's vibration is difficult to be damped and the accuracy is limited. The vibration suppressing results are not good enough in the existing research because only the longitudinal direction vibration is considered while the normal direction vibration is neglected. The parameters of the direct-axis current controller are set to be the same as those of the quadrature-axis current controller commonly. This causes contradiction between signal noise and response. To suppress the vibration, the electromagnetic force model of the flat permanent magnet synchronous linear motor is formulated first. Through the analysis of the effect that direct-axis current noise and quadrature-axis current noise have on both direction vibration, it can be declared that the conclusion that longitudinal direction vibration is only related to the quadrature-axis current noise while the normal direction vibration is related to both the quadrature-axis current noise and direct-axis current noise. Then, the simulation test on current loop with a low-pass filter is conducted and the results show that the low-pass filter can not suppress the vibration but makes the vibration more severe. So a vibration suppressing strategy that the proportional gain of direct-axis current controller adapted according to quadrature-axis reference current is proposed. This control strategy can suppress motor vibration by suppressing direct-axis current noise. The experiments results about the effect of K p and T i on normal direction vibration, longitudinal vibration and the position step response show that this strategy suppresses vibration effectively while the motor's motion performance is not affected. The maximum reduction of vibration can be up to 40%. In addition, current test under rated load condition is also conducted and the results show that the control strategy can avoid the conflict between the direct-axis current and the quadrature-axis current under typical load. Adaptive PI control strategy can effectively suppress the flat permanent magnet linear synchronous motor's vibration without affecting the motor's performance.

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.

The subject-fixated coaxially sighted corneal light reflex: a clinical marker for centration of refractive treatments and devices.

PubMed

Chang, Daniel H; Waring, George O

2014-11-01

To describe the inconsistencies in definition, application, and usage of the ocular reference axes (optical axis, visual axis, line of sight, pupillary axis, and topographic axis) and angles (angle kappa, lambda, and alpha) and to propose a precise, reproducible, clinically defined reference marker and axis for centration of refractive treatments and devices. Perspective. Literature review of papers dealing with ocular reference axes, angles, and centration. The inconsistent definitions and usage of the current ocular axes, as derived from eye models, limit their clinical utility. With a clear understanding of Purkinje images and a defined alignment of the observer, light source/fixation target, and subject eye, the subject-fixated coaxially sighted corneal light reflex can be a clinically useful reference marker. The axis formed by connecting the subject-fixated coaxially sighted corneal light reflex and the fixation point, the subject-fixated coaxially sighted corneal light reflex axis, is independent of pupillary dilation and phakic status of the eye. The relationship of the subject-fixated coaxially sighted corneal light reflex axis to a refined definition of the visual axis without reference to nodal points, the foveal-fixation axis, is discussed. The displacement between the subject-fixated coaxially sighted corneal light reflex and pupil center is described not by an angle, but by a chord, here termed chord mu. The application of the subject-fixated coaxially sighted corneal light reflex to the surgical centration of refractive treatments and devices is discussed. As a clinically defined reference marker, the subject-fixated coaxially sighted corneal light reflex avoids the shortcomings of current ocular axes for clinical application and may contribute to better consensus in the literature and improved patient outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

The role of the hypothalamus-pituitary-adrenal/interrenal axis in mediating predator-avoidance trade-offs.

PubMed

Harris, Breanna N; Carr, James A

2016-05-01

Maintaining energy balance and reproducing are important for fitness, yet animals have evolved mechanisms by which the hypothalamus-pituitary-adrenal/interrenal (HPA/HPI) axis can shut these activities off. While HPA/HPI axis inhibition of feeding and reproduction may have evolved as a predator defense, to date there has been no review across taxa of the causal evidence for such a relationship. Here we review the literature on this topic by addressing evidence for three predictions: that exposure to predators decreases reproduction and feeding, that exposure to predators activates the HPA/HPI axis, and that predator-induced activation of the HPA/HPI axis inhibits foraging and reproduction. Weight of evidence indicates that exposure to predator cues inhibits several aspects of foraging and reproduction. While the evidence from fish and mammals supports the hypothesis that predator cues activate the HPA/HPI axis, the existing data in other vertebrate taxa are equivocal. A causal role for the HPA axis in predator-induced suppression of feeding and reproduction has not been demonstrated to date, although many studies report correlative relationships between HPA activity and reproduction and/or feeding. Manipulation of HPA/HPI axis signaling will be required in future studies to demonstrate direct mediation of predator-induced inhibition of feeding and reproduction. Understanding the circuitry linking sensory pathways to their control of the HPA/HPI axis also is needed. Finally, the role that fear and anxiety pathways play in the response of the HPA axis to predator cues is needed to better understand the role that predators have played in shaping anxiety related behaviors in all species, including humans. Copyright © 2016 Elsevier Inc. All rights reserved.

High-precision processing and detection of the high-caliber off-axis aspheric mirror

NASA Astrophysics Data System (ADS)

Dai, Chen; Li, Ang; Xu, Lingdi; Zhang, Yingjie

2017-10-01

To achieve the efficient, controllable, digital processing and high-precision detection of the high-caliber off-axis aspheric mirror, meeting the high-level development needs of the modern high-resolution, large field of space optical remote sensing camera, we carried out the research on high precision machining and testing technology of off-axis aspheric mirror. First, we forming the off-axis aspheric sample with diameter of 574mm × 302mm by milling it with milling machine, and then the intelligent robot equipment was used for off-axis aspheric high precision polishing. Surface detection of the sample will be proceed with the off-axis aspheric contact contour detection technology and offaxis non-spherical surface interference detection technology after its fine polishing using ion beam equipment. The final surface accuracy RMS is 12nm.

Wide acceptance angle, high concentration ratio, optical collector

NASA Technical Reports Server (NTRS)

Kruer, Mark A. (Inventor)

1991-01-01

A cassegrain optical system provides improved collection of off-axis light yet is still characterized by a high concentration ratio. The optical system includes a primary mirror for collecting incoming light and reflecting the light to a secondary mirror which, in turn, reflects the light to a solar cell or other radiation collection device. The primary mirror reflects incoming on-axis light onto an annular section of the secondary mirror and results in the reflection of a substantial amount of incoming off-axis light onto the remainder of the secondary mirror. Thus light which would otherwise be lost to the system will be captured by the collector. Furthermore, the off-axis sections of the secondary mirror may be of a different geometrical shape than the on-axis annular section so as to optimize the amount of off-axis light collected.

Centrifugally activated bearing for high-speed rotating machinery

DOEpatents

Post, Richard F.

1994-01-01

A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation.

Effects of off-axis loading on the tensile behavior of a ceramic-matrix composite

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

Lynch, C.S.; Evans, A.G.

A 0{degree}/90{degree} ceramic-matrix composite (CMC) comprised of Nicalon fibers in magnesium aluminosilicate (MAS) has been loaded in tension in three orientations relative to the fiber direction: 0, 30, and 45{degree}. The off-axis loaded samples exhibit inelastic deformation at appreciably lower stresses than samples loads at 0{degree}. Matrix cracking governs the inelastic strains in all orientations. But, important differences in the morphologies and sequencing of the cracks account for the differences in the stress levels. Off-axis failure also occurs at substantially lower stresses than on-axis failure. On-axis composite failure is governed by fiber fracture, but off-axis failure involves matrix-crack coalescence. Tomore » facilitate interpretation and modeling of these behaviors, the interface friction and debond stresses have been determined from hysteresis measurements.« less

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.

The role of electrocardiography in evaluation of severity of chronic obstructive pulmonary disease in daily clinical practice.

PubMed

Aktürk, Faruk; Bıyık, İsmail; Kocaş, Cüneyt; Ertürk, Mehmet; Yalçın, Ahmet Arif; Savaş, Ayfer Utku; Kuzer, Firuzan Pınar; Uzun, Fatih; Yıldırım, Aydın; Uslu, Nevzat; Çuhadaroğlu, Çağlar

2013-01-01

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of chronic morbidity and mortality. Bronchial obstruction and increased pulmonary vascular resistance impairs right atrial functions. In this study, we aimed to investigate the effect of bronchial obstruction on p wave axis in patients with COPD and usefulness of electrocardiography (ECG) in the evaluation of the severity of COPD. Ninety five patients (64 male and 31 female) included to the study. Patients were in sinus rhythm, with normal ejection fraction and heart chamber sizes. Their respiratory function tests and 12 lead electrocardiograms were obtained at same day. Correlations with severity of COPD and ECG findings including p wave axis, p wave duration, QRS axis, QRS duration were studied. The mean age was 58 ± 12 years. Their mean p wave axis was 62 ± 18 degrees. In this study, p wave axis has demonstrated significant positive correlations with stages of COPD and QRS axis but significant negative correlations with FEV1, FEF, BMI and QRS duration. P wave axis increases with increasing stages of COPD. Verticalization of the frontal p wave axis may be an early finding of worsening of COPD before occurrences of other ECG changes of hypertrophy and enlargement of right heart chambers such as p pulmonale. Verticalization of the frontal p wave axis reflecting right atrial electrical activity and right heart strain may be a useful parameter for quick estimation of the severity of COPD in an out-patient cared.

Stressor-specific effects of sex on HPA axis hormones and activation of stress-related neurocircuitry.

PubMed

Babb, Jessica A; Masini, Cher V; Day, Heidi E W; Campeau, Serge

2013-11-01

Experiencing stress can be physically and psychologically debilitating to an organism. Women have a higher prevalence of some stress-related mental illnesses, the reasons for which are unknown. These experiments explore differential HPA axis hormone release in male and female rats following acute stress. Female rats had a similar threshold of HPA axis hormone release following low intensity noise stress as male rats. Sex did not affect the acute release, or the return of HPA axis hormones to baseline following moderate intensity noise stress. Sensitive indices of auditory functioning obtained by modulation of the acoustic startle reflex by weak pre-pulses did not reveal any sexual dimorphism. Furthermore, male and female rats exhibited similar c-fos mRNA expression in the brain following noise stress, including several sex-influenced stress-related regions. The HPA axis response to noise stress was not affected by stage of estrous cycle, and ovariectomy significantly increased hormone release. Direct comparison of HPA axis hormone release to two different stressors in the same animals revealed that although female rats exhibit robustly higher HPA axis hormone release after restraint stress, the same effect was not observed following moderate and high intensity loud noise stress. Finally, the differential effect of sex on HPA axis responses to noise and restraint stress cannot readily be explained by differential social cues or general pain processing. These studies suggest the effect of sex on acute stress-induced HPA axis hormone activity is highly dependent on the type of stressor.

The apelin-APJ axis: A novel potential therapeutic target for organ fibrosis.

PubMed

Huang, Shifang; Chen, Linxi; Lu, Liqun; Li, Lanfang

2016-05-01

Apelin, an endogenous ligand of the G-protein-coupled receptor APJ, is expressed in a diverse number of organs. The apelin-APJ axis helps to control the processes of pathological and physiological fibrosis, including renal fibrosis, cardiac fibrosis, liver fibrosis and pulmonary fibrosis. However, the role of apelin-APJ in organ fibrosis remains controversial due to conflicting study results. The apelin-APJ axis is a detrimental mechanism which promotes liver fibrosis mainly via up-regulation the expression of collagen-II and platelet-derived growth factor receptor β (PDGFRβ). On the contrary, the apelin-APJ axis is beneficial for renal fibrosis, cardiac fibrosis and pulmonary fibrosis. The apelin-APJ axis alleviates renal fibrosis by restraining the expression of transforming growth factor-β1 (TGF-β1). In addition, the apelin-APJ axis attenuates cardiac fibrosis through multiple pathways. Furthermore, the apelin-APJ axis has beneficial effects on experimental bronchopulmonary dysplasia (BPD) and acute respiratory distress syndrome (ARDS) which suggest the apelin-APJ axis potentially alleviates pulmonary fibrosis. In this article, we review the controversies associated with apelin-APJ in organ fibrosis and introduce the drugs that target apelin-APJ. We conclude that future studies should place more emphasis on the relationship among apelin isoforms, APJ receptor subtypes and organ fibrosis. The apelin-APJ axis will be a potential therapeutic target and those drugs targeted for apelin-APJ may constitute a novel therapeutic strategy for renal fibrosis, cardiac fibrosis, liver fibrosis and pulmonary fibrosis. Copyright © 2016 Elsevier B.V. All rights reserved.

Underwater (UW) Unexploded Ordnance (UXO) Multi-Sensor Data Base (MSDB) Collection

DTIC Science & Technology

2009-07-01

11 FIGURE 6 RTG SENSOR. FOUR SENSOR TRIADS ARE SHOWN, EACH WITH A 3-AXIS FLUXGATE MAGNETOMETER ...used by RTG to measure the gradients. Each triad includes a 3-axis fluxgate magnetometer and a set of feedback coils. The outputs of three triad...each with a 3-axis fluxgate magnetometer (internal, not clearly visible) and a set of 3 feedback coils. The upper triad 3-axis magnetometer

Laparoscopic simulation interface

DOEpatents

Rosenberg, Louis B.

2006-04-04

A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

Modeling and experiment of three-degree-of-freedom actuators using piezoelectric buzzers

NASA Astrophysics Data System (ADS)

Chen, W. M.; Liu, T. S.

2013-10-01

This study presents innovative three-degree-of-freedom piezoelectric actuators. Under the piezoelectric force and dry friction, the piezoelectric actuators not only can move in the Z-axis direction, but also rotate around the Y-axis and Z-axis. The Z-axis displacement can reach 62 mm and the rotation angle around the Y-axis and Z-axis can reach 270° and 360°, respectively. Compared with the literature, this innovative actuator design achieves one-degree-of-freedom translation and two-degree-of-freedom rotation. Equations of motion are derived based on the piezoelectric properties and Newton’s law. Two types of actuators are created in this study. In the first type, the centers of four piezoelectric buzzers are attached to an arm while in the other type each rim of the four piezoelectric buzzers is attached to the arm. Experimental results are compared with theoretical results. According to the experimental results, the present actuator can accomplish a translational velocity of 11 mm s-1, a Y-axis angular velocity of 8.96 rad s-1, a Z-axis angular velocity of 2.63 rad s-1, and a force of 2.49 mN. By using four piezoelectric buzzers, this study creates piezoelectric actuators capable of both translational and rotational motions.

Structural Performance of a Hybrid FRP-Aluminum Modular Triangular Truss System Subjected to Various Loading Conditions

PubMed Central

Zhang, Dongdong; Huang, Yaxin; Zhao, Qilin; Li, Fei; Gao, Yifeng

2014-01-01

A novel hybrid FRP-aluminum truss system has been employed in a two-rut modular bridge superstructure composed of twin inverted triangular trusses. The actual flexural behavior of a one-rut truss has been previously investigated under the on-axis loading test; however, the structural performance of the one-rut truss subjected to an off-axis load is still not fully understood. In this paper, a geometrical linear finite element model is introduced and validated by the on-axis loading test; the structural performance of the one-rut truss subjected to off-axis load was numerically obtained; the dissimilarities of the structural performance between the two different loading cases are investigated in detail. The results indicated that (1) the structural behavior of the off-axis load differs from that of the on-axis load, and the off-axis load is the critical loading condition controlling the structural performance of the triangular truss; (2) under the off-axis load, the FRP trussed members and connectors bear certain out-of-plane bending moments and are subjected to a complicated stress state; and (3) the stress state of these members does not match that of the initial design, and optimization for the redesign of these members is needed, especially for the pretightened teeth connectors. PMID:25254254

Model surgery with a passive robot arm for orthognathic surgery planning.

PubMed

Theodossy, Tamer; Bamber, Mohammad Anwar

2003-11-01

The aims of the study were to assess the degree of accuracy of model surgery performed manually using the Eastman technique and to compare it with model surgery performed with the aid of a robot arm. Twenty-one patients undergoing orthognathic surgery gave consent for this study. They were divided into 2 groups based on the model surgery technique used. Group A (52%) had model surgery performed manually, whereas group B (48%) had their model surgery performed using the robot arm. Patients' maxillary casts were measured before and after model surgery, and results were compared with those for the original treatment plan in horizontal (x-axis), vertical (y-axis), and transverse (z-axis) planes. Statistical analysis using Mann-Whitney U test for x- and y-axis and independent sample t test for z-axis have shown significant differences between both groups in x-axis (P =.024) and y-axis (P =.01) but not in z-axis (P =.776). Model surgery performed with the aid of a robot arm is significantly more accurate in anteroposterior and vertical planes than is manual model surgery. Robot arm has an important role to play in orthognathic surgery planning and in determining the biometrics of orthognathic surgical change at the model surgery stage.

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.

Autonomy-connectedness and internalizing-externalizing personality psychopathology, among outpatients.

PubMed

Bachrach, Nathan; Bekker, Marrie H J; Croon, Marcel A

2013-07-01

The aims of this research were to investigate gender differences in levels of autonomy-connectedness, Axis I Psychopathology, and higher order factors of internalizing and externalizing personality psychopathology and, second, to investigate the association between these variables. The design of this research is cross-sectional and multicentered. We used self-report questionnaires, factor analysis, and regression analysis. We found evidence for a significant role of autonomy-connectedness in Axis I Psychopathology. This was especially true for women, who were found to be more sensitive to others and sensitivity to others was strongly associated with Axis I Psychopathology. Maybe due to the research sample no evidence was found for an association of autonomy-connectedness with externalizing psychopathology. As to the role of autonomy-connectedness in internalizing psychopathology, we found that a lack of self-awareness or a capacity of managing new situations, combined with a high sensitivity to others, were associated with internalizing psychopathology. Women appeared to be more sensitive to others and to report higher levels of Axis I Psychopathology than men. We conclude that autonomy-connectedness plays an important role in Axis I Psychopathology as well as in internalizing Axis II pathology. Treatment of Axis I and internalizing Axis II psychopathology should therefore also focus on autonomy problems. © 2012 Wiley Periodicals, Inc.

Endocannabinoid Signaling, Glucocorticoid-Mediated Negative Feedback and Regulation of the HPA Axis

PubMed Central

Hill, M. N.; Tasker, J. G.

2012-01-01

The hypothalamic-pituitary-adrenal (HPA) axis regulates the outflow of glucocorticoid hormones under basal conditions and in response to stress. Within the last decade, a large body of evidence has mounted indicating that the endocannabinoid system is involved in the central regulation of the stress response; however, the specific role endocannabinoid signalling plays in phases of HPA axis regulation, or the neural sites of action mediating this regulation, was not mapped out until recently. This review aims to collapse the current state of knowledge regarding the role of the endocannabinoid system in the regulation of the HPA axis to put together a working model of how and where endocannabinoids act within the brain to regulate outflow of the HPA axis. Specifically, we discuss the role of the endocannabinoid system in the regulation of the HPA axis under basal conditions, activation in response to acute stress and glucocorticoid-mediated negative feedback. Interestingly, there appears to be some anatomical specificity to the role of the endocannabinoid system in each phase of HPA axis regulation, as well as distinct roles of both anandamide and 2-arachidonoylglycerol in these phases. Ultimately, the current level of information indicates that endocannabinoid signalling acts to suppress HPA axis activity through concerted actions within the prefrontal cortex, amygdala and hypothalamus. PMID:22214537

Hypothalamic-pituitary-adrenal axis functioning and dysfunctional attitude in depressed patients with and without childhood neglect.

PubMed

Peng, Hongjun; Long, Ying; Li, Jie; Guo, Yangbo; Wu, Huawang; Yang, YuLing; Ding, Yi; He, Jianfei; Ning, Yuping

2014-02-18

To date, the relationships between childhood neglect, hypothalamic-pituitary-adrenal (HPA) axis functioning and dysfunctional attitude in depressed patients are still obscure. The Childhood Trauma Questionnaire (CTQ) was used to assess childhood emotional neglect and physical neglect. Twenty-eight depressed patients with childhood neglect and 30 depressed patients without childhood neglect from Guangzhou Psychiatric Hospital were compared with 29 age- and gender-matched control subjects without childhood neglect and 22 control subjects with childhood neglect. Cortisol awakening response, the difference between the cortisol concentrations at awakening and 30 minutes later, provided a measure of HPA axis functioning. The Dysfunctional Attitude Scale measured cognitive schema. HPA axis functioning was significantly increased in depressed patients with childhood neglect compared with depressed patients without childhood neglect (p < 0.001). HPA axis activity in the control group with childhood neglect was significantly higher than in the depressed group without childhood neglect (p < 0.001). Total scores of childhood neglect were positively correlated with HPA axis functioning and dysfunctional attitude scores, but not with severity of depression. We did not find correlations with HPA axis functioning and dysfunctional attitude or with the Hamilton Rating Scale for Depression scores. Childhood neglect may cause hyperactivity of the HPA axis functioning and dysfunctional attitude, but does not affect depression severity.

New agents modulating the renin-angiotensin-aldosterone system—Will there be a new therapeutic option?

PubMed Central

Szoka, Piotr; Kolodziejczyk, Patrycjusz; Kramkowski, Karol; Wojewodzka-Zelezniakowicz, Marzena; Chabielska, Ewa

2016-01-01

The renin-angiotensin-aldosterone system (RAAS) is more complex than it was originally regarded. According to the current subject knowledge, there are two main axes of the RAAS: (1) angiotensin-converting enzyme (ACE)-angiotensin II-AT1 receptor axis and (2) ACE2-angiotensin-(1-7)-Mas receptor axis. The activation of the first axis leads to deleterious effects, including vasoconstriction, endothelial dysfunction, thrombosis, inflammation, and fibrosis; therefore, blocking the components of this axis is a highly rational and commonly used therapeutic procedure. The ACE2-Ang-(1-7)-Mas receptor axis has a different role, since it often opposes the effects induced by the classical ACE-Ang II-AT1 axis. Once the positive effects of the ACE2-Ang-(1-7)-Mas axis were discovered, the alternative ways of pharmacotherapy activating this axis of RAAS appeared. This article briefly describes new molecules affecting the RAAS, namely: recombinant human ACE2, ACE2 activators, angiotensin-(1-7) peptide and non-peptide analogs, aldosterone synthase inhibitors, and the third and fourth generation of mineralocorticoid receptor antagonists. The results of the experimental and clinical studies are encouraging, which leads us to believe that these new molecules can support the treatment of cardiovascular diseases as well as cardiometabolic disorders. PMID:27439538

The relationship between anisotropic magnetoresistance and topology of Fermi surface in Td-MoTe2 crystal

NASA Astrophysics Data System (ADS)

Lv, Yang-Yang; Li, Xiao; Pang, Bin; Cao, Lin; Lin, Dajun; Zhang, Bin-Bin; Yao, Shu-Hua; Chen, Y. B.; Zhou, Jian; Dong, Song-Tao; Zhang, Shan-Tao; Lu, Ming-Hui; Chen, Yan-Feng

2017-07-01

Layered transition-metal dichalcogenides have been recently attracted a lot of attention because of their unique physical properties, such as extremely large and anisotropic magnetoresistance (MR) in WTe2. In this work, we observed the abnormally anisotropic MR on Td-MoTe2 crystal that is strongly dependent on the temperature, as well as the orientations of both magnetic field B and electric field E with respect to crystallographic axes of Td-MoTe2. When E//a-axis and B//c-axis, MR is parabolically dependent on B and is as high as 520% under 9 T and 2 K conditions; the MR is quasi-linearly dependent on B when E//a-axis and B//b-axis (E//b-axis and B//c-axis), and the corresponding MR is only 130% (220%); MR is initially parabolically dependent on B, then linearly on B, and finally shows a saturate trend under E//B//a-axis (or E//B//b-axis) conditions, and the MR is about 16% (30%). These anisotropic MR behaviors can be qualitatively explained by the features of the Fermi surface of Td-MoTe2. This work may demonstrate the rich anisotropic physical behavior in layered transition-metal dichalcognides.

Flexible metallic seal for transition duct in turbine system

DOEpatents

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

2014-04-22

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a flexible metallic seal contacting the interface member to provide a seal between the interface member and the turbine section.

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.

Convolution seal for transition duct in turbine system

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

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston

2015-05-26

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface feature for interfacing with an adjacent transition duct. The turbine system further includes a convolution seal contacting the interface feature to provide a seal between the interface feature andmore » the adjacent transition duct.« less

Convolution seal for transition duct in turbine system

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

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston

2015-03-10

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a convolution seal contacting the interface member to provide a seal between the interface member and themore » turbine section.« less

Transition duct with divided upstream and downstream portions

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

McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Maldonado, Jaime Javier

2015-07-14

Turbine systems are provided. In one embodiment, a turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion extending from the inlet and a downstream portion extending from the outlet. The turbine system further includes a rib extending from an outer surface of the duct passage, the rib dividing themore » upstream portion and the downstream portion.« less

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.

Why does a spinning egg rise?

NASA Astrophysics Data System (ADS)

Cross, Rod

2018-03-01

Experimental and theoretical results are presented concerning the rise of a spinning egg. It was found that an egg rises quickly while it is sliding and then more slowly when it starts rolling. The angular momentum of the egg projected in the XZ plane changed in the same direction as the friction torque, as expected, by rotating away from the vertical Z axis. The latter result does not explain the rise. However, an even larger effect arises from the Y component of the angular momentum vector. As the egg rises, the egg rotates about the Y axis, an effect that is closely analogous to rotation of the egg about the Z axis. Both effects can be described in terms of precession about the respective axes. Steady precession about the Z axis arises from the normal reaction force in the Z direction, while precession about the Y axis arises from the friction force in the Y direction. Precession about the Z axis ceases if the normal reaction force decreases to zero, and precession about the Y axis ceases if the friction force decreases to zero.

A scheiner-principle vernier optometer

NASA Astrophysics Data System (ADS)

Cushman, William B.

1989-06-01

A method and optometer apparatus is disclosed for measuring the dark focus of accommodation. In a preferred embodiment, the optometer apparatus includes: a pinhole aperture plate having first and second horizontally positioned apertures disposed on opposite sides of a first optical axis; first and second orthogonally-oriented polarizing filters respectively covering the first and second horizontally positioned apertures; a positive lens having an optical axis on the first optical axis and being positioned at a distance of approximately one focal length from the pinhole aperture plate; a lens system having an optical axis on the first optical axis; a slit aperture plate having a vertical slit and being disposed on the first optical axis and between the positive lens and the lens system; third and fourth vertically positioned polarizing filters selectively disposed adjacent to the slit aperture plate to divide the slit vertically, a monochromatic light source for propagating light along the first optical axis through the lens system; and movable means attached to the slit aperture plate, the lens system and the monochromatic light source for moving the slit aperture plate.

Standardizing the atomic description, axis and centre of biological ion channels.

PubMed

Kaats, Adrian J; Galiana, Henrietta L; Nadeau, Jay L

2007-09-15

A general representation of the atomic co-ordinates of a biological ion channel is obtained from a definition of channel axis and centre. Through rotation and translation of the channel, its centre becomes the origin of the standard co-ordinate system, and the channel axis becomes the system's z-axis. A method for determining the channel axis and centre based on the concepts of mass centre and mass moment of inertia is presented. The method for determining the channel axis can be directly applied to channels that adhere to two specific conditions regarding their geometry and mass distribution. Specific examples are given for Gramicidin A (GA), and the mammalian potassium channel Kv 1.2. For channels that do not adhere to these conditions, minor modifications of these procedures can be applied in determining the channel axis. Specific examples are given for the outer membrane bacterial porin OmpF, and for the staphylococcal pore-forming toxin alpha-hemolysin (alpha HL). The definitions and procedures presented are made in an effort to establish a standard basis for performing, sharing, and comparing computations in a consistent manner.

The determination of the direction of the optic axis of uniaxial crystalline materials

NASA Technical Reports Server (NTRS)

Lock, J. A.; Schock, H. J.; Regan, C. A.

1986-01-01

The birefringence of crystalline substances in general, and of sapphire in particular, is described. A test is described whose purpose is to determine the direction of the optic axis of a cylindrically machined single crystal of sapphire. This test was performed on the NASA Lewis sapphire cylinder and it was found that the optic axis made an angle of 18 deg with the axis of symmetry of the cylinder.

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.

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.

Energy density and energy flux in the focus of an optical vortex: reverse flux of light energy.

PubMed

Kotlyar, Victor V; Kovalev, Alexey A; Nalimov, Anton G

2018-06-15

Using the Richards-Wolf formulas for an arbitrary circularly polarized optical vortex with an integer topological charge m, we obtain explicit expressions for all components of the electric and magnetic field strength vectors near the focus, as well as expressions for the intensity (energy density) and for the energy flux (components of the Poynting vector) in the focal plane of an aplanatic optical system. For m=2, from the obtained expressions it follows that the energy flux near the optical axis propagates in the reversed direction, rotating along a spiral around the optical axis. On the optical axis itself, the reversed flux is maximal and decays rapidly with the distance from the axis. For m=3, in contrast, the reversed energy flux in the focal plane is minimal (zero) on the optical axis and increases (until the first ring of the light intensity) as a squared distance from the axis.

Orthogonally referenced integrated ensemble for navigation and timing

DOEpatents

Smith, Stephen Fulton; Moore, James Anthony

2013-02-26

An orthogonally referenced integrated ensemble for navigation and timing includes a dual-polyhedral oscillator array, including an outer sensing array of oscillators and an inner clock array of oscillators situated inside the outer sensing array. The outer sensing array includes a first pair of sensing oscillators situated along a first axis of the outer sensing array, a second pair of sensing oscillators situated along a second axis of the outer sensing array, and a third pair of sensing oscillators situated along a third axis of the outer sensing array. The inner clock array of oscillators includes a first pair of clock oscillators situated along a first axis of the inner clock array, a second pair of clock oscillators situated along a second axis of the inner clock array, and a third pair of clock oscillators situated along a third axis of the inner clock array.

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).

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.

Articulated transition duct in turbomachine

DOEpatents

Flanagan, James Scott; McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray

2014-04-29

Turbine systems are provided. A turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion and a downstream portion. The upstream portion extends from the inlet between an inlet end and an aft end. The downstream portion extends from the outlet between an outlet end and a head end. The turbine system further includes a joint coupling the aft end of the upstream portion and the head end of the downstream portion together. The joint is configured to allow movement of the upstream portion and the downstream portion relative to each other about or along at least one axis.

Orthogonally referenced integrated ensemble for navigation and timing

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

Smith, Stephen Fulton; Moore, James Anthony

2014-04-01

An orthogonally referenced integrated ensemble for navigation and timing includes a dual-polyhedral oscillator array, including an outer sensing array of oscillators and an inner clock array of oscillators situated inside the outer sensing array. The outer sensing array includes a first pair of sensing oscillators situated along a first axis of the outer sensing array, a second pair of sensing oscillators situated along a second axis of the outer sensing array, and a third pair of sensing oscillators situated along a third axis of the outer sensing array. The inner clock array of oscillators includes a first pair of clockmore » oscillators situated along a first axis of the inner clock array, a second pair of clock oscillators situated along a second axis of the inner clock array, and a third pair of clock oscillators situated along a third axis of the inner clock array.« less

Centrifugally activated bearing for high-speed rotating machinery

DOEpatents

Post, R.F.

1994-02-15

A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation. 4 figures.

Mixing Characteristics of Elliptical Jet Control with Crosswire

NASA Astrophysics Data System (ADS)

Manigandan, S.; Vijayaraja, K.

2018-02-01

The aerodynamic mixing efficiency of elliptical sonic jet flow with the effect of crosswire is studied computationally and experimentally at different range of nozzle pressure ratio with different orientation along the minor axis of the exit. The cross wire of different orientation is found to reduce the strength of the shock wave formation. Due to the presence of crosswire the pitot pressure oscillation is reduced fast, which weakens the shock cell structure. When the cross wire is placed at center position we see high mixing along the major axis. Similarly, when the cross wire is placed at ¼ and ¾ position we see high mixing promotion along minor axis. It also proves, as the position of the cross wire decreased along minor axis there will be increase in the mixing ratio. In addition to that we also found that, jet spread is high in major axis compared to minor axis due to bifurcation of jet along upstream

Steerable vertical to horizontal energy transducer for mobile robots

DOEpatents

Spletzer, Barry L.; Fischer, Gary J.; Feddema, John T.

2001-01-01

The present invention provides a steerable vertical to horizontal energy transducer for mobile robots that less complex and requires less power than two degree of freedom tilt mechanisms. The present invention comprises an end effector that, when mounted with a hopping actuator, translates along axis (typically vertical) actuation into combined vertical and horizontal motion. The end effector, or foot, mounts with an end of the actuator that moves toward the support surface (typically a floor or the earth). The foot is shaped so that the first contact with the support surface is off the axis of the actuator. Off-axis contact with the support surface generates an on-axis force (typically resulting in vertical motion) and a moment orthogonal to the axis. The moment initiates a horizontal tumbling motion, and tilts the actuator so that its axis is oriented with a horizontal component and continued actuation generates both vertical and horizontal force.

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.

Hatching success of ostrich eggs in relation to setting, turning and angle of rotation.

PubMed

van Schalkwyk, S J; Cloete, S W; Brown, C R; Brand, Z

2000-03-01

1. Three trials were designed to study the effects of axis of setting, turning frequency and axis and angle of rotation on the hatching success of ostrich eggs. The joint effects of axis of setting and angle of rotation were investigated in a fourth trial. 2. The hatchability of fertile ostrich eggs artificially incubated in electronic incubators (turned through 60 degrees hourly) was improved substantially in eggs set in horizontal positions for 2 or 3 weeks and vertically for the rest of the time. 3. The hatchability of fertile eggs set in the horizontal position without any turning was very low (27%). It was improved to approximately 60% by manual turning through 180 degrees around the short axis and through 60 degrees around the long axis at 08.00 and 16.00 h. A further improvement to approximately 80% was obtained in eggs automatically turned through 60 degrees around the long axis in the incubator. Additional turning through 180 degrees around the short axis twice daily at 08.00 and 16.00 h resulted in no further improvement. 4. The hatchability of fertile eggs set vertically in electronic incubators and rotated hourly through angles ranging from 60 degrees to 90 degrees around the short axis increased linearly over the range studied. The response amounted to 1.83% for an increase of 10 (R2=0.96). 5. The detrimental effect of rotation through the smaller angle of 60 degrees around the short axis could be compensated for by setting ostrich eggs in the horizontal position for 2 weeks before putting them in the vertical position.

Silencing of Smed-betacatenin1 generates radial-like hypercephalized planarians.

PubMed

Iglesias, Marta; Gomez-Skarmeta, Jose Luis; Saló, Emili; Adell, Teresa

2008-04-01

Little is known about the molecular mechanisms responsible for axis establishment during non-embryonic processes such as regeneration and homeostasis. To address this issue, we set out to analyze the role of the canonical Wnt pathway in planarians, flatworms renowned for their extraordinary morphological plasticity. Canonical Wnt signalling is an evolutionarily conserved mechanism to confer polarity during embryonic development, specifying the anteroposterior (AP) axis in most bilaterians and the dorsoventral (DV) axis in early vertebrate embryos. beta-Catenin is a key element in this pathway, although it is a bifunctional protein that is also involved in cell-cell adhesion. Here, we report the characterization of two beta-catenin homologs from Schmidtea mediterranea (Smed-betacatenin1/2). Loss of function of Smed-betacatenin1, but not Smed-betacatenin2, in both regenerating and intact planarians, generates radial-like hypercephalized planarians in which the AP axis disappears but the DV axis remains unaffected, representing a unique example of a striking body symmetry transformation. The radial-like hypercephalized phenotype demonstrates the requirement for Smed-betacatenin1 in AP axis re-establishment and maintenance, and supports a conserved role for canonical Wnt signalling in AP axis specification, whereas the role of beta-catenin in DV axis establishment would be a vertebrate innovation. When considered alongside the protein domains present in each S. mediterranea beta-catenin and the results of functional assays in Xenopus embryos demonstrating nuclear accumulation and axis induction with Smed-betacatenin1, but not Smed-betacatenin2, these data suggest that S. mediterranea beta-catenins could be functionally specialized and that only Smed-betacatenin1 is involved in Wnt signalling.

Precision grip responses to unexpected rotational perturbations scale with axis of rotation.

PubMed

De Gregorio, Michael; Santos, Veronica J

2013-04-05

It has been established that rapid, pulse-like increases in precision grip forces ("catch-up responses") are elicited by unexpected translational perturbations and that response latency and strength scale according to the direction of linear slip relative to the hand as well as gravity. To determine if catch-up responses are elicited by unexpected rotational perturbations and are strength-, axis-, and/or direction-dependent, we imposed step torque loads about each of two axes which were defined relative to the subject's hand: the distal-proximal axis away from and towards the subject's palm, and the grip axis which connects the two fingertips. Precision grip responses were dominated initially by passive mechanics and then by active, unimodal catch-up responses. First dorsal interosseous activity, marking the start of the catch-up response, began 71-89 ms after the onset of perturbation. The onset latency, shape, and duration (217-231 ms) of the catch-up response were not affected by the axis, direction, or magnitude of the rotational perturbation, while strength was scaled by axis of rotation and slip conditions. Rotations about the grip axis that tilted the object away from the palm and induced rotational slip elicited stronger catch-up responses than rotations about the distal-proximal axis that twisted the object between the digits. To our knowledge, this study is the first to investigate grip responses to unexpected torque loads and to show characteristic, yet axis-dependent, catch-up responses for conditions other than pure linear slip. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Spacecraft attitude calibration/verification baseline study

NASA Technical Reports Server (NTRS)

Chen, L. C.

1981-01-01

A baseline study for a generalized spacecraft attitude calibration/verification system is presented. It can be used to define software specifications for three major functions required by a mission: the pre-launch parameter observability and data collection strategy study; the in-flight sensor calibration; and the post-calibration attitude accuracy verification. Analytical considerations are given for both single-axis and three-axis spacecrafts. The three-axis attitudes considered include the inertial-pointing attitudes, the reference-pointing attitudes, and attitudes undergoing specific maneuvers. The attitude sensors and hardware considered include the Earth horizon sensors, the plane-field Sun sensors, the coarse and fine two-axis digital Sun sensors, the three-axis magnetometers, the fixed-head star trackers, and the inertial reference gyros.

Long-axis view for ultrasound-guided central venous catheter placement via the internal jugular vein.

PubMed

Mahan, Angel F; McEvoy, Matthew D; Gravenstein, Nikolaus

2016-04-01

In modern practice, real-time ultrasound guidance is commonly employed for the placement of internal jugular vein catheters. With a new tool, such as ultrasound, comes the opportunity to refine and further optimize the ultrasound view during jugular vein catheterization. We describe jugular vein access techniques and use the long-axis view as an alternative to the commonly employed short-axis cross-section view for internal jugular vein access and cannulation. The long-axis ultrasound-guided internal jugular vein approach for internal jugular vein cannulation is a useful alternative technique that can provide better needle tip and guidewire visualization than the more traditional short-axis ultrasound view.

Double diameter boring tool

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

Ashbaugh, F.N.; Murry, K.R.

A method of boring two concentric holes of different depths is described utilizing an elongated boring tool having a tool axis of rotation, a longitudinally disposed tool centerline axis, and first and second transverse cutting edges at one end thereof extending across the boring tool, the second cutting edge being longitudinally rearwardly recessed with respect to the first cutting edge. The method consists of inserting the boring tool into an adjustable boring head, adjusting a distance B between the tool centerline axis and the tool axis of rotation such that the tool axis of rotation intersects a first boring areamore » of the first cutting edge; and boring the concentric holes having respectively larger and smaller diameters.« less

Heliostat for astronomical usage

NASA Technical Reports Server (NTRS)

Heyde, G.

1979-01-01

The design of a heliostat is presented. The invention consists of a mechanical polar axis which can rotate and which is parallel to the world axis. A mirror is supported in such a way that it can be rotated arbitrarily around a declination axis which is perpendicular to it. After execution of this rotation, the mirror can be clamped in the plane of the world axis, which can be corrected and verified by special collimation directions. The clockwork or drive unit can be driven for a 24 or 48 hour complete rotation of the axis using any known device such as switchable gears, without changing its regular variation related to stellar time or mean solar time.

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

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.

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.

Method and apparatus for providing high bandwidth, low noise mechanical I/O for computer systems

DOEpatents

Rosenberg, Louis B.

1998-01-01

A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

Multiple degree-of-freedom mechanical interface to a computer system

DOEpatents

Rosenberg, Louis B.

2001-01-01

A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

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.

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.

The high-efficiency laundry metering and marketing analysis (THELMA) project: Volume 2 -- Laboratory testing of clothes washers. Final report

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

NONE

1997-10-01

Horizontal axis (H-axis) clothes washers use less water and energy than conventional top-loading vertical axis (V-axis) clothes washers, yet sales in the US are insignificant. In the High Efficiency Laundry Metering and Market Analysis (THELMA) project, EPRI and a group of utilities have pooled their resources to develop the basis for successful DSM programs to accelerate the acceptance of this technology in the US market. This report covers the laboratory test phase of the THELMA project. The objective of this effort was to measure the performance of a representative sample of currently manufactured H-axis washers and to compare this performancemore » to that of a typical V-axis washer. Several aspects of performance were measured, with the emphasis on measures of energy consumption and water consumption: DOE washer capacity; hot and cold water consumption; energy consumption by the washer mechanical drive; DOE energy factor; water extraction effectiveness; effect of water extraction effectiveness on dryer energy; soil removal effectiveness; rinsing effectiveness; and gentleness of action. Eight H-axis washers, provided by US or European manufacturers, were tested. Test results varied over a range for these eight machines, but on average, the H-axis washers used 40% less energy (normalized to basket volume) and 25% less water (normalized to basket volume) when measured according to the DOE test procedure.« less

Laboratory testing of clothes washers. Final report

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

Dieckmann, J.; Murphy, W.

1995-12-01

Horizontal axis (H-axis) clothes washers use less water and energy than conventional top-loading vertical axis (V-axis) clothes washers, yet sales in the US are insignificant. In the High Efficiency Laundry Metering and Market Analysis (THELMA) project, EPRI and a group of utilities have pooled their resources to develop the basis for successful DSM programs to accelerate the acceptance of this technology in the US market. This report covers the laboratory test phase of the THELMA project. The objective of this effort was to measure the performance of a representative sample of currently manufactured H-axis washers and to compare this performancemore » to that of a typical V-axis washer. Several aspects of performance were measured, with the emphasis on measures of energy consumption and water consumption: DOE washer capacity; Hot and cold water consumption; Energy consumption by the washer mechanical drive; DOE energy factor; Water extraction effectiveness; Effect of water extraction effectiveness on dryer energy; Soil removal effectiveness; Rinsing effectiveness and Gentleness of action. Six H-axis washers, provided by US or European manufacturers, were tested. Test results varied over a range for these six machines, but on average, the H-axis washers used 40% less energy (normalized to basket volume) and 25% less water (normalized to basket volume) when measured according to the DOE test procedure.« less

Clinical Features and Management of Acquired Resistance to PD-1 Axis Inhibitors in 26 Patients With Advanced Non-Small Cell Lung Cancer.

PubMed

Gettinger, Scott N; Wurtz, Anna; Goldberg, Sarah B; Rimm, David; Schalper, Kurt; Kaech, Susan; Kavathas, Paula; Chiang, Anne; Lilenbaum, Rogerio; Zelterman, Daniel; Politi, Katerina; Herbst, Roy S

2018-06-01

With expanding indications for programmed death 1 (PD-1) axis inhibitors in non-small cell lung cancer (NSCLC), acquired resistance (AR) to these therapies is increasingly being encountered. We sought to characterize clinical patterns of AR to PD-1 axis inhibitors in patients with advanced NSCLC, and evaluate subsequent outcome and management strategies for such patients. Patients with NSCLC who developed AR to PD-1 axis inhibitor therapy initiated between December 2009 and February 2016 at one institution were identified and examined by clinical and radiographic features. AR was defined as progressive disease after initial response by either Response Evaluation Criteria in Solid Tumors v1.1 or immune-related response criteria. Twenty-six patients with AR to PD-1 axis inhibitor therapy were identified and evaluated. Median time to AR was 313 days; the 2-year survival rate from AR was 70% (95% confidence interval: 0.53-0.92). Twenty patients (77%) experienced AR in lymph nodes (LNs), including 11 patients with LN-only progression. Twenty-three (88%) patients had recurrence limited to one (54%) or two (35%) sites of disease. Fourteen patients (54%) continued PD-1 axis inhibitor therapy beyond progression. Three patients were re-challenged with the same PD-1 axis inhibitor after holiday from and progression off therapy, 2 again responded. Fifteen patients (58%) received local therapy to site(s) of AR, 11 continued respective PD-1 axis inhibitor after local therapy. The 2-year survival rate from AR among these 15 patients was 92% (95% confidence interval: 0.77-1). Acquired resistance to PD-1 axis inhibitors is often limited to one or two sites when local therapy and continuation of PD-1 axis inhibitor therapy can result in prolonged benefit. LN metastases appear to be particularly susceptible sites to AR. When progression of disease following response occurs after holiday from PD-1 axis inhibitor, re-challenge can again lead to tumor regression. Copyright © 2018 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

75 FR 34077 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on Five Petitions to List Seven...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-16

...) Habitat requirements for feeding, breeding, and sheltering; (b) Genetics and taxonomy; (c) Historical and...), cattle (Bos taurus), goats (Capra hircus), and axis deer (Axis axis), is considered one of the primary...

West Europe Report

DTIC Science & Technology

1987-04-22

long while the north-south axis coincides approximately with 96 the area of the Grisons Canton. These axial routes lead from numerous...operations. All routes, with the exception of the Engadine axis, merge into the Saint Bernard axis. The interior of Grisons , and particularly the Saint

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 using kinetic energy recovery drive systems.

Structure and Dynamics of the Southeast Indian Ridge, 129°E to 140°E, and Off-axis Volcanism: Preliminary Results of the STORM Cruise

NASA Astrophysics Data System (ADS)

Briais, Anne; Barrère, Fabienne; Boulart, Cédric; Ceuleneer, Georges; Ferreira, Nicolas; Hanan, Barry; Hémond, Christophe; Macleod, Sarah; Maia, Marcia; Maillard, Agnès; Merkuryev, Sergey; Park, Sung-Hyun; Révillon, Sidonie; Ruellan, Etienne; Schohn, Alexandre; Watson, Sally; Yang, Yun-Seok

2016-04-01

We present observations of the South-East Indian Ridge (SEIR) collected during the STORM cruise (South Tasmania Ocean Ridge and Mantle) on the N/O L'Atalante early 2015. The SEIR between Australia and Antarctica displays large variations of axial morphology despite an almost constant intermediate spreading rate. The Australia-Antarctic Discordance (AAD) between 120°E and 128°E is a section of the mid-ocean ridge where the magma budget is abnormally low, and which marks the boundary between Indian and Pacific mantle domains with distinct geochemical isotopic compositions. The STORM project focuses on the area east of the discordance from 128 to 140°E, where gravity highs observed on satellite-derived maps of the flanks of the SEIR reveal numerous volcanic seamounts. A major objective of the STORM cruise was to test the hypothesis of a mantle flow from the Pacific to the Indian domains. We collected multibeam bathymetry and magnetic data between 136 and 138°E to map off-axis volcanic ridges up to 10 Ma-old crust. We mapped the SEIR axis between 129 and 140°E, and the northern part of the George V transform fault. We collected rock samples on seamounts and in the transform fault, basaltic glass samples along the ridge axis, and near-bottom samples and in-situ measurements in the water column. Our observations reveal that the off-axis seamounts form near the SEIR axis, are not associated to off-axis deformation of the ocean floor, and are often located near the traces of ridge axis discontinuities. We also observe a general shallowing of the ridge axis from the AAD to the George V TF and the presence of robust axial segments near the transform fault. Our new data allow us to describe the complex evolution of the transform fault system. They also permit to locate new hydrothermal systems along the ridge axis.

Exploring point-cloud features from partial body views for gender classification

NASA Astrophysics Data System (ADS)

Fouts, Aaron; McCoppin, Ryan; Rizki, Mateen; Tamburino, Louis; Mendoza-Schrock, Olga

2012-06-01

In this paper we extend a previous exploration of histogram features extracted from 3D point cloud images of human subjects for gender discrimination. Feature extraction used a collection of concentric cylinders to define volumes for counting 3D points. The histogram features are characterized by a rotational axis and a selected set of volumes derived from the concentric cylinders. The point cloud images are drawn from the CAESAR anthropometric database provided by the Air Force Research Laboratory (AFRL) Human Effectiveness Directorate and SAE International. This database contains approximately 4400 high resolution LIDAR whole body scans of carefully posed human subjects. Success from our previous investigation was based on extracting features from full body coverage which required integration of multiple camera images. With the full body coverage, the central vertical body axis and orientation are readily obtainable; however, this is not the case with a one camera view providing less than one half body coverage. Assuming that the subjects are upright, we need to determine or estimate the position of the vertical axis and the orientation of the body about this axis relative to the camera. In past experiments the vertical axis was located through the center of mass of torso points projected on the ground plane and the body orientation derived using principle component analysis. In a natural extension of our previous work to partial body views, the absence of rotational invariance about the cylindrical axis greatly increases the difficulty for gender classification. Even the problem of estimating the axis is no longer simple. We describe some simple feasibility experiments that use partial image histograms. Here, the cylindrical axis is assumed to be known. We also discuss experiments with full body images that explore the sensitivity of classification accuracy relative to displacements of the cylindrical axis. Our initial results provide the basis for further investigation of more complex partial body viewing problems and new methods for estimating the two position coordinates for the axis location and the unknown body orientation angle.

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, Gsk3β-independent control mechanism of β-catenin and implicates Ccr7 as a long-hypothesized GPCR regulating vertebrate axis formation. PMID:23055828

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.

The anteroposterior axis of the tibia in Korean patients undergoing total knee replacement.

PubMed

Kim, C W; Seo, S S; Kim, J H; Roh, S M; Lee, C R

2014-11-01

The aim of this study was to find anatomical landmarks for rotational alignment of the tibial component in total knee replacement (TKR) in a CT-based study. Pre-operative CT scanning was performed on 94 South Korean patients (nine men, 85 women, 188 knees) with osteoarthritis of the knee joint prior to TKR. The tibial anteroposterior (AP) axis was defined as a line perpendicular to the femoral surgical transepicondylar axis and passing through the centre of the posterior cruciate ligament (PCL). The angles between the defined tibial AP axis and anatomical landmarks at various levels of the tibia were measured. The mean values of the angles between the defined tibial AP axis and the line connecting the anterior border of the proximal third of the tibia to the centre of the PCL was -0.2° (-17 to 14.1, sd 4.1). This was very close to the defined tibial axis, and remained so regardless of lower limb alignment and the degree of tibial bowing. Therefore, AP axis defined as described, is a reliable anatomical landmark for rotational alignment of tibial components. ©2014 The British Editorial Society of Bone & Joint Surgery.

Projection Reduction Exposure with Variable Axis Immersion Lenses (PREVAIL)-A High Throughput E-Beam Projection Approach for Next Generation Lithography

NASA Astrophysics Data System (ADS)

Pfeiffer, Hans

1999-12-01

Projection reduction exposure with variable axis immersion lenses (PREVAIL) represents the high throughput e-beam projection approach to next generation lithography (NGL), which IBM is pursuing in cooperation with Nikon Corporation as an alliance partner. This paper discusses the challenges and accomplishments of the PREVAIL project. The supreme challenge facing all e-beam lithography approaches has been and still is throughput. Since the throughput of e-beam projection systems is severely limited by the available optical field size, the key to success is the ability to overcome this limitation. The PREVAIL technique overcomes field-limiting off-axis aberrations through the use of variable axis lenses, which electronically shift the optical axis simultaneously with the deflected beam, so that the beam effectively remains on axis. The resist images obtained with the proof-of-concept (POC) system demonstrate that PREVAIL effectively eliminates off-axis aberrations affecting both the resolution and placement accuracy of pixels. As part of the POC system a high emittance gun has been developed to provide uniform illumination of the patterned subfield, and to fill the large numerical aperture projection optics designed to significantly reduce beam blur caused by Coulombinteraction.

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.

Vection during conflicting multisensory information about the axis, magnitude, and direction of self-motion.

PubMed

Ash, April; Palmisano, Stephen

2012-01-01

We examined the vection induced by consistent and conflicting multisensory information about self-motion. Observers viewed displays simulating constant-velocity self-motion in depth while physically oscillating their heads left-right or back-forth in time with a metronome. Their tracked head movements were either ignored or incorporated directly into the self-motion display (as an added simulated self-acceleration). When this head oscillation was updated into displays, sensory conflict was generated by simulating oscillation along: (i) an orthogonal axis to the head movement; or (ii) the same axis, but in a non-ecological direction. Simulated head oscillation always produced stronger vection than 'no display oscillation'--even when the axis/direction of this display motion was inconsistent with the physical head motion. When head-and-display oscillation occurred along the same axis: (i) consistent (in-phase) horizontal display oscillation produced stronger vection than conflicting (out-of-phase) horizontal display oscillation; however, (ii) consistent and conflicting depth oscillation conditions did not induce significantly different vection. Overall, orthogonal-axis oscillation was found to produce very similar vection to same-axis oscillation. Thus, we conclude that while vection appears to be very robust to sensory conflict, there are situations where sensory consistency improves vection.

Monolithically integrated tri-axis shock accelerometers with MHz-level high resonant-frequency

NASA Astrophysics Data System (ADS)

Zou, Hongshuo; Wang, Jiachou; Chen, Fang; Bao, Haifei; Jiao, Ding; Zhang, Kun; Song, Zhaohui; Li, Xinxin

2017-07-01

This paper reports a novel monolithically integrated tri-axis high-shock accelerometer with high resonant-frequency for the detection of a broad frequency-band shock signal. For the first time, a resonant-frequency as high as about 1.4 MHz is designed for all the x-, y- and z-axis accelerometers of the integrated tri-axis sensor. In order to achieve a wide frequency-band detection performance, all the three sensing structures are designed into an axially compressed/stretched tiny-beam sensing scheme, where the p  +  -doped tiny-beams are connected into a Wheatstone bridge for piezoresistive output. By using ordinary (1 1 1) silicon wafer (i.e. non-SOI wafer), a single-wafer based fabrication technique is developed to monolithically integrate the three sensing structures for the tri-axis sensor. Testing results under high-shock acceleration show that each of the integrated three-axis accelerometers exhibit about 1.4 MHz resonant-frequency and 0.2-0.4 µV/V/g sensitivity. The achieved high frequencies for all the three sensing units make the tri-axis sensor promising in high fidelity 3D high-shock detection applications.

Twinning of amphibian embryos by centrifugation

NASA Technical Reports Server (NTRS)

Black, S. D.

1984-01-01

In the frog Xenopus laevis, the dorsal structures of the embryonic body axis normally derive from the side of the egg opposite the side of sperm entry. However, if the uncleaved egg is inclined at lg or centrifuged in an inclined position, this topographic relationship is overridden: the egg makes its dorsal axial structures according to its orientation in the gravitational/centrifugal field, irrespective of the position of sperm entry. Certain conditions of centrifugation cause eggs to develop into conjoined twins with two sets of axial structures. A detailed analysis of twinning provided some insight into experimental axis orientation. First, as with single-axis embryos, both axes in twins are oriented according to the direction of centrifugation. One axis forms at the centripetal side of the egg and the other forms at the centrifugal side, even when the side of sperm entry is normal to the centrifugal force vector. Second, if eggs are centrifuged to give twins, but are inclined at lg to prevent post-centrifugation endoplasmic redistributions, only single-axis embryos develop. Thus, a second redistribution is required for high-frequency secondary axis formation. This can be accomplished by lg (as in the single centrifugations) or by a second centrifugation directed along the egg's animal-vegetal axis.

Roller-gear drives for robotic manipulators design, fabrication and test

NASA Technical Reports Server (NTRS)

Anderson, William J.; Shipitalo, William

1991-01-01

Two single axis planetary roller-gear drives and a two axis roller-gear drive with dual inputs were designed for use as robotic transmissions. Each of the single axis drives is a two planet row, four planet arrangement with spur gears and compressively loaded cylindrical rollers acting in parallel. The two axis drive employs bevel gears and cone rollers acting in parallel. The rollers serve a dual function: they remove backlash from the system, and they transmit torque when the gears are not fully engaged.

AF-Geospace User’s Manual Version 2.5.1 and Version 2.51P

DTIC Science & Technology

2012-08-01

system of the grid. The choices are: GEOC: Geocentric coordinate system: The Z axis is aligned with the north rotational pole, the X axis pierces...the Greenwich Meridian on the equator (0 o Long, 0 o Lat), and the Y axis is minus the cross-product of X and Z. GSM: Geocentric solar magnetospheric...handed system and is positive towards dusk. GEI: Geocentric equatorial inertial coordinate system: The Z axis is the same as for the geocentric

Method and apparatus for measuring birefringent particles

DOEpatents

Bishop, James K.; Guay, Christopher K.

2006-04-18

A method and apparatus for measuring birefringent particles is provided comprising a source lamp, a grating, a first polarizer having a first transmission axis, a sample cell and a second polarizer having a second polarization axis. The second polarizer has a second polarization axis that is set to be perpendicular to the first polarization axis, and thereby blocks linearly polarized light with the orientation of the beam of light passing through the first polarizer. The beam of light passing through the second polarizer is measured using a detector.

Shock compression and release of a-axis magnesium single crystals: Anisotropy and time dependent inelastic response

DOE PAGES

Renganathan, P.; Winey, J. M.; Gupta, Y. M.

2017-01-19

Here, to gain insight into inelastic deformation mechanisms for shocked hexagonal close-packed (hcp) metals, particularly the role of crystal anisotropy, magnesium (Mg) single crystals were subjected to shock compression and release along the a-axis to 3.0 and 4.8 GPa elastic impact stresses. Wave profiles measured at several thicknesses, using laser interferometry, show a sharply peaked elastic wave followed by the plastic wave. Additionally, a smooth and featureless release wave is observed following peak compression. When compared to wave profiles measured previously for c-axis Mg, the elastic wave amplitudes for a-axis Mg are lower for the same propagation distance, and less attenuation of elastic wave amplitude is observed for a given peak stress. The featureless release wave for a-axis Mg is in marked contrast to the structured features observed for c-axis unloading. Numerical simulations, using a time-dependent anisotropic modeling framework, showed that the wave profiles calculated using prismatic slip or (10more » $$\\bar{1}$$2) twinning, individually, do not match the measured compression profiles for a-axis Mg. However, a combination of slip and twinning provides a good overall match to the measured compression profiles. In contrast to compression,prismatic slip alone provides a reasonable match to the measured release wave profiles; (10$$\\bar{1}$$2) twinning due to its uni-directionality is not activated during release. The experimental results and wave profile simulations for a-axis Mg presented here are quite different from the previously published c-axis results, demonstrating the important role of crystal anisotropy on the time-dependent inelastic deformation of Mg single crystals under shock compression and release.« less

The Parallel Implementation of Algorithms for Finding the Reflection Symmetry of the Binary Images

NASA Astrophysics Data System (ADS)

Fedotova, S.; Seredin, O.; Kushnir, O.

2017-05-01

In this paper, we investigate the exact method of searching an axis of binary image symmetry, based on brute-force search among all potential symmetry axes. As a measure of symmetry, we use the set-theoretic Jaccard similarity applied to two subsets of pixels of the image which is divided by some axis. Brute-force search algorithm definitely finds the axis of approximate symmetry which could be considered as ground-truth, but it requires quite a lot of time to process each image. As a first step of our contribution we develop the parallel version of the brute-force algorithm. It allows us to process large image databases and obtain the desired axis of approximate symmetry for each shape in database. Experimental studies implemented on "Butterflies" and "Flavia" datasets have shown that the proposed algorithm takes several minutes per image to find a symmetry axis. However, in case of real-world applications we need computational efficiency which allows solving the task of symmetry axis search in real or quasi-real time. So, for the task of fast shape symmetry calculation on the common multicore PC we elaborated another parallel program, which based on the procedure suggested before in (Fedotova, 2016). That method takes as an initial axis the axis obtained by superfast comparison of two skeleton primitive sub-chains. This process takes about 0.5 sec on the common PC, it is considerably faster than any of the optimized brute-force methods including ones implemented in supercomputer. In our experiments for 70 percent of cases the found axis coincides with the ground-truth one absolutely, and for the rest of cases it is very close to the ground-truth.

Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition

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

Li, Ye; Karri, Naveen K.; Wang, Qi

Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studiesmore » on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.« less

Hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes: sex differences in regulation of stress responsivity.

PubMed

Oyola, Mario G; Handa, Robert J

2017-09-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism's response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic-pituitary-gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life.

Two distinct events, section compression and loss of particles ("lost caps"), contribute to z-axis distortion and bias in optical disector counting.

PubMed

Baryshnikova, Larisa M; Von Bohlen Und Halbach, Oliver; Kaplan, Suleyman; Von Bartheld, Christopher S

2006-09-01

Deformation of tissue sections in the z-axis can bias optical disector counting. When samples of particle densities are not representative for the entire tissue section, significant bias of estimated numbers can result. To assess the occurrence, prevalence, extent, sequence of events, and causes of z-axis distortion, the distribution of neuronal nucleoli in thick paraffin and vibratome sections was determined in chicken, rodent, and human brain tissues. When positions of neuronal nucleoli were measured in the z-axis, nucleoli were more frequent at the surfaces (bottom and top) of tissue sections than in the core. This nonlinear z-axis distribution was not lab-, equipment-, or investigator-specific, and was independent of age, fixation quality, coverslipping medium, or paraffin melting temperature, but in paraffin sections, was highly correlated with the tilt of the knife (cutting) angle. Manipulation of subsequent tissue processing steps revealed that two events contribute to z-axis distortion. Initially, a higher density of particles results at surfaces after sectioning, apparently due to section compression. Subsequently, particles can be lost to varying degrees from surfaces during floating or staining and dehydration, resulting in "lost caps." These results may explain different degrees of z-axis distortion between different types of sections and different labs, and reinforce the importance of checking z-axis distributions as a "quality control" prior to selection of guard zones in optical disector counting. Indirect approaches to assess section quality, such as resectioning in a perpendicular plane, yield additional artifacts, and should be replaced by a direct quantitative measurement of z-axis distribution of particles. (c) 2006 Wiley-Liss, Inc.

Shock compression and release of a-axis magnesium single crystals: Anisotropy and time dependent inelastic response

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

Renganathan, P.; Winey, J. M.; Gupta, Y. M.

Here, to gain insight into inelastic deformation mechanisms for shocked hexagonal close-packed (hcp) metals, particularly the role of crystal anisotropy, magnesium (Mg) single crystals were subjected to shock compression and release along the a-axis to 3.0 and 4.8 GPa elastic impact stresses. Wave profiles measured at several thicknesses, using laser interferometry, show a sharply peaked elastic wave followed by the plastic wave. Additionally, a smooth and featureless release wave is observed following peak compression. When compared to wave profiles measured previously for c-axis Mg, the elastic wave amplitudes for a-axis Mg are lower for the same propagation distance, and less attenuation of elastic wave amplitude is observed for a given peak stress. The featureless release wave for a-axis Mg is in marked contrast to the structured features observed for c-axis unloading. Numerical simulations, using a time-dependent anisotropic modeling framework, showed that the wave profiles calculated using prismatic slip or (10more » $$\\bar{1}$$2) twinning, individually, do not match the measured compression profiles for a-axis Mg. However, a combination of slip and twinning provides a good overall match to the measured compression profiles. In contrast to compression,prismatic slip alone provides a reasonable match to the measured release wave profiles; (10$$\\bar{1}$$2) twinning due to its uni-directionality is not activated during release. The experimental results and wave profile simulations for a-axis Mg presented here are quite different from the previously published c-axis results, demonstrating the important role of crystal anisotropy on the time-dependent inelastic deformation of Mg single crystals under shock compression and release.« less

Activation of the hypothalamic-pituitary-adrenal axis in lithium-induced conditioned taste aversion learning.

PubMed

Jahng, Jeong Won; Lee, Jong-Ho

2015-12-05

Intraperitoneal injections (ip) of lithium chloride at large doses induce c-Fos expression in the brain regions implicated in conditioned taste aversion (CTA) learning, and also activate the hypothalamic-pituitary-adrenal (HPA) axis and increase the plasma corticosterone levels in rats. A pharmacologic treatment blunting the lithium-induced c-Fos expression in the brain regions, but not the HPA axis activation, induced CTA formation. Synthetic glucocorticoids at conditioning, but not glucocorticoid antagonist, attenuated the lithium-induced CTA acquisition. The CTA acquisition by ip lithium was not affected by adrenalectomy regardless of basal corticosterone supplement, but the extinction was delayed in the absence of basal corticosterone. Glucocorticoids overloading delayed the extinction memory formation of lithium-induced CTA. ip lithium consistently induced the brain c-Fos expression, the HPA activation and CTA formation regardless of the circadian activation of the HPA axis. Intracerebroventricular (icv) injections of lithium at day time also increased the brain c-Fos expression, activated the HPA axis and induced CTA acquisition. However, icv lithium at night, when the HPA axis shows its circadian activation, did not induce CTA acquisition nor activate the HPA axis, although it increased the brain c-Fos expression. These results suggest that the circadian activation of the HPA axis may affect central, but not peripheral, effect of lithium in CTA learning in rats, and the HPA axis activation may be necessary for the central effect of lithium in CTA formation. Also, glucocorticoids may be required for a better extinction; however, increased glucocorticoids hinder both the acquisition and the extinction of lithium-induced CTA. Copyright © 2015. Published by Elsevier B.V.

Evolution of Axis Specification Mechanisms in Jawed Vertebrates: Insights from a Chondrichthyan

PubMed Central

Coolen, Marion; Sauka-Spengler, Tatjana; Nicolle, Delphine; Le-Mentec, Chantal; Lallemand, Yvan; Silva, Corinne Da; Plouhinec, Jean-Louis; Robert, Benoît; Wincker, Patrick; Shi, De-Li; Mazan, Sylvie

2007-01-01

The genetic mechanisms that control the establishment of early polarities and their link with embryonic axis specification and patterning seem to substantially diverge across vertebrates. In amphibians and teleosts, the establishment of an early dorso-ventral polarity determines both the site of axis formation and its rostro-caudal orientation. In contrast, amniotes retain a considerable plasticity for their site of axis formation until blastula stages and rely on signals secreted by extraembryonic tissues, which have no clear equivalents in the former, for the establishment of their rostro-caudal pattern. The rationale for these differences remains unknown. Through detailed expression analyses of key development genes in a chondrichthyan, the dogfish Scyliorhinus canicula, we have reconstructed the ancestral pattern of axis specification in jawed vertebrates. We show that the dogfish displays compelling similarities with amniotes at blastula and early gastrula stages, including the presence of clear homologs of the hypoblast and extraembryonic ectoderm. In the ancestral state, these territories are specified at opposite poles of an early axis of bilateral symmetry, homologous to the dorso-ventral axis of amphibians or teleosts, and aligned with the later forming embryonic axis, from head to tail. Comparisons with amniotes suggest that a dorsal expansion of extraembryonic ectoderm, resulting in an apparently radial symmetry at late blastula stages, has taken place in their lineage. The synthesis of these results with those of functional analyses in model organisms supports an evolutionary link between the dorso-ventral polarity of amphibians and teleosts and the embryonic-extraembryonic organisation of amniotes. It leads to a general model of axis specification in gnathostomes, which provides a comparative framework for a reassessment of conservations both among vertebrates and with more distant metazoans. PMID:17440610

Hypothalamic–pituitary–adrenal and hypothalamic–pituitary–gonadal axes: sex differences in regulation of stress responsivity

PubMed Central

Oyola, Mario G.; Handa, Robert J.

2018-01-01

Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic–pituitary–adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism’s response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic–pituitary–gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life. PMID:28859530

Sacroiliac joint motion in patients with degenerative lumbar spine disorders.

PubMed

Nagamoto, Yukitaka; Iwasaki, Motoki; Sakaura, Hironobu; Sugiura, Tsuyoshi; Fujimori, Takahito; Matsuo, Yohei; Kashii, Masafumi; Murase, Tsuyoshi; Yoshikawa, Hideki; Sugamoto, Kazuomi

2015-08-01

OBJECT Usually additional anchors into the ilium are necessary in long fusion to the sacrum for degenerative lumbar spine disorders (DLSDs), especially for adult spine deformity. Although the use of anchors is becoming quite common, surgeons must always keep in mind that the sacroiliac (SI) joint is mobile and they should be aware of the kinematic properties of the SI joint in patients with DLSDs, including adult spinal deformity. No previous study has clarified in vivo kinematic changes in the SI joint with respect to patient age, sex, or parturition status or the presence of DLSDs. The authors conducted a study to clarify the mobility and kinematic characteristics of the SI joint in patients with DLSDs in comparison with healthy volunteers by using in vivo 3D motion analysis with voxel-based registration, a highly accurate, noninvasive method. METHODS Thirteen healthy volunteers (the control group) and 20 patients with DLSDs (the DLSD group) underwent low-dose 3D CT of the lumbar spine and pelvis in 3 positions (neutral, maximal trunk flexion, and maximal trunk extension). SI joint motion was calculated by computer processing of the CT images (voxel-based registration). 3D motion of the SI joint was expressed as both 6 df by Euler angles and translations on the coordinate system and a helical axis of rotation. The correlation between joint motion and the cross-sectional area of the trunk muscles was also investigated. RESULTS SI joint motion during trunk flexion-extension was minute in healthy volunteers. The mean rotation angles during trunk flexion were 0.07° around the x axis, -0.02° around the y axis, and 0.16° around the z axis. The mean rotation angles during trunk extension were 0.38° around the x axis, -0.08° around the y axis, and 0.08° around the z axis. During trunk flexion-extension, the largest amount of motion occurred around the x axis. In patients with DLSDs, the mean rotation angles during trunk flexion were 0.57° around the x axis, 0.01° around the y axis, and 0.19° around the z axis. The mean rotation angles during trunk extension were 0.68° around the x axis, -0.11° around the y axis, and 0.05° around the z axis. Joint motion in patients with DLSDs was significantly greater, with greater individual difference, than in healthy volunteers. Among patients with DLSDs, women had significantly more motion than men did during trunk extension. SI joint motion was significantly negatively correlated with the cross-sectional area of the trunk muscles during both flexion and extension of the trunk. CONCLUSIONS The authors elucidated the mobility and kinematic characteristics of the SI joint in patients with DLSDs compared with healthy volunteers for the first time. This information is useful for spine surgeons because of the recent increase in spinopelvic fusion for the treatment of DLSDs.

Relationship between the tibial mechanical axis and bony anatomical landmarks of the calf and foot as measured on radiographs obtained with a new laser-calibrated position.

PubMed

He, Peiheng; Zhu, Qi; Zhang, Zhaohui; Zou, Xuenong; Xu, Dongliang

2013-01-01

To investigate relationship between the tibial mechanical axis and bony landmarks of the calf and foot by developing a new laser-calibrated position for radiography of the lower limb. A total of 120 volunteers were randomly divided into two groups. All subjects were marked with skin projection of the hypothetical axis of the calf on the frontal and sagittal planes. Radiographs of weight-bearing full-length lower-limb were obtained by the laser-calibrated positioning in the experimental group, and by the use of conventional technique in the control group. To consider the rotation of the calf, radiological features of the knee and ankle were investigated. The relationship between the tibial mechanical axis and the bony landmarks of the calf and foot were also measured. Anteroposterior view depicted a tangential projection on the superior/inferior tibiofibular syndesmosis and between lateral malleolus and talus in ankle mortise in the experimental group. Bony overlap on the superior/inferior tibiofibular syndesmosis and between lateral malleolus and talus was seen in control group. On the tangential projection, it also presented a clear wheel-like contour of the medial femoral condyle, but a partial overlap between medial femoral condyle and tibial plateau. The femoral joint angle between the connecting line at the lowest point of the medial and lateral femoral condyles and the tibial mechanical axis was 83.6° ± 2.49° in the experimental group and 85.3° ± 2.18° in the control group (P < 0.001). The tibial tubercle-axis distance from the center of the medial and middle one-third of the tibial tubercle to the tibial mechanical axis was 1.5 mm in the experimental group and 3.7 mm in the control group (P < 0.05). The malleoli-axis distance from the midpoint of the bimalleolar line joining the tips of the medial and lateral malleoli to the tibial mechanical axis was 1.9 mm in the experimental group and 6.9 mm in the control group (P < 0.001). Lateral view showed no difference between the tibial mechanical axis and the fibular reference line within two groups. In the new radiographic position, our data indicate that the hypothetical tibial mechanical axis and fibular reference line, obtained by marking the specified anatomic landmarks of the calf and foot, are located more closely to the tibial mechanical axis by correcting the rotation of the calf and foot during the radiography. On anteroposterior view, the tibial mechanical axis was approximately 2 mm medial to the center of the ankle. This indicates that the hypothetical tibial mechanical axis marked on the skin could be referred to guide the tibial osteotomy in total knee arthroplasty.

Turbine system

DOEpatents

McMahan, Kevin Weston; Dillard, Daniel Jackson

2016-05-03

A turbine system is disclosed. The turbine system includes a transition duct having an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The turbine system further includes a turbine section connected to the transition duct. The turbine section includes a plurality of shroud blocks at least partially defining a hot gas path, a plurality of buckets at least partially disposed in the hot gas path, and a plurality of nozzles at least partially disposed in the hot gas path. At least one of a shroud block, a bucket, or a nozzle includes means for withstanding high temperatures.

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.

Study on off-axis detection of pulsed laser in atmosphere

NASA Astrophysics Data System (ADS)

Liang, Weiwei

2018-02-01

Laser communication, designation, and ranging are point to point and have a high degree of specificity, current laser detection, such as laser warning receiver system, could detect the scattering laser from the off-axis distance by scattering track on natural aerosols, which is helpful to locate the laser source. However, the intensity of the scattering laser is extremely weak and affected by many factors, in order to evaluate the detection characteristic, a simplified model of off-axis detection for scattering laser in the lower atmosphere based on the Mie scattering theory is presented in this paper, the performances of the off-axis laser detection in different conditions such as off-axis distance, visibility, incidence angle, and delay time are investigated.

Psychiatric Comorbidity and Physical Correlates in Alcohol-dependent Patients.

PubMed

Gauba, Deepak; Thomas, Pramod; Balhara, Yatan P S; Deshpande, Smita N

2016-01-01

To examine the prevalence and pattern of comorbidity in alcohol dependence and its relationship with physical and laboratory findings. Eighty males with alcohol dependence were examined using the Hindi version of Diagnostic Interview for Genetic Studies, the International Classification of Disease-10 th Edition Personality Disorder Examination, Alcohol Use Disorder Identification Test for alcohol use, global assessment of functioning, blood sampling electrocardiogram, and ultrasonogram. Eighty-seven percent had a comorbid Axis I or an Axis II psychiatric disorder, over 78% had nicotine dependence, and 56% had comorbid Axis II disorder, antisocial personality being the most common. Gamma glutamyl transpeptidase levels were significantly associated with comorbidity. High comorbidity of Axis I psychiatric disorders was found among persons with alcohol dependence. Axis II disorders were also present.

Tidal friction and generalized Cassini's laws in the solar system. [for planetary spin axis rotation

NASA Technical Reports Server (NTRS)

Ward, W. R.

1975-01-01

The tidal drift toward a generalized Cassini state of rotation of the spin axis of a planet or satellite in a precessing orbit is described. Generalized Cassini's laws are applied to several solar system objects and the location of their spin axes estimated. Of those considered only the moon definitely occupies state 2 with the spin axis near to the normal of the invariable plane. Most objects appear to occupy state 1 with the spin axis near to the orbit normal. Iapetus could occupy either state depending on its oblateness. In addition, the resonant rotation of Mercury is found to have little effect on the tidal drift of its spin axis toward state 1.

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.

On LAM's and SAM's for Halley's rotation

NASA Technical Reports Server (NTRS)

Peale, Stanton J.

1992-01-01

Non principal axis rotation for comet Halley is inferred from dual periodicities evident in the observations. The modes where the spin axis precesses around the axis of minimum moment of inertia (long axis mode or LAM) and where it precesses around the axis of maximum moment of inertia (short axis mode or SAM) are described from an inertial point of view. The currently favored LAM model for Halley's rotation state satisfies observational and dynamical constraints that apparently no SAM can satisfy. But it cannot reproduce the observed post perihelion brightening through seasonal illumination of localized sources on the nucleus, whereas a SAM can easily produce post or pre perihelion brightening by this mechanism. However, the likelihood of a LAM rotation for elongated nuclei of periodic comets such as Halley together with Halley's extreme post perihelion behavior far from the Sun suggest that Halley's post perihelion brightening may be due to effects other than seasonal illumination of localized sources, and therefore such brightening may not constrain its rotation state.

Method and apparatus for measuring shear modulus and viscosity of a monomolecular film

DOEpatents

Abraham, B.M.; Miyano, K.; Ketterson, J.B.

1983-10-18

Apparatus for measuring the shear modulus of a monomolecular film comprises a circular trough having inwardly sloping sides containing a liquid for supporting the monolayer on the surface thereof; a circular rotor suspended above the trough such that the lower surface of the rotor contacts the surface of the liquid, positioned such that the axis of the rotor is concentric with the axis of the trough and freely rotable about its axis; means for hydrostatically compressing the monolayer in the annular region formed between the rotor and the sides of the trough; and means for rotating the trough about its axis. Preferably, hydrostatic compression of the monolayer is achieved by removing liquid from the bottom of the trough (decreasing the surface area) while raising the trough vertically along its axis to maintain the monolayer at a constant elevation (and maintain rotor contact). In order to measure viscosity, a means for rotating the rotor about its axis is added to the apparatus.

Method and apparatus for measuring shear modulus and viscosity of a monomolecular film

DOEpatents

Abraham, Bernard M.; Miyano, Kenjiro; Ketterson, John B.

1985-01-01

Instrument for measuring the shear modulus of a monomolecular film comprises a circular trough having inwardly sloping sides containing a liquid for supporting the monolayer on the surface thereof; a circular rotor suspended above the trough such that the lower surface of the rotor contacts the surface of the liquid, positioned such that the axis of the rotor is concentric with the axis of the trough and freely rotable about its axis; apparatus for hydrostatically compressing the monolayer in the annular region formed between the rotor and the sides of the trough; and apparatus for rotating the trough about its axis. Preferably, hydrostatic compression of the monolayer is achieved by removing liquid from the bottom of the trough (decreasing the surface area) while raising the trough vertically along its axis to maintain the monolayer at a constant elevation (and maintain rotor contact). In order to measure viscosity, a apparatus for rotating the rotor about its axis is added to the apparatus.

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.

Childhood maltreatment and adult psychopathology: pathways to hypothalamic-pituitary-adrenal axis dysfunction

PubMed Central

Mello, Marcelo F.; Faria, Alvaro A.; Mello, Andrea F.; Carpenter, Linda L.; Tyrka, Audrey R.; Price, Lawrence H.

2015-01-01

Objective The aim of this paper was to examine the relationship between childhood maltreatment and adult psychopathology, as reflected in hypothalamic-pituitary-adrenal axis dysfunction. Method A selective review of the relevant literature was undertaken in order to identify key and illustrative research findings. Results There is now a substantial body of preclinical and clinical evidence derived from a variety of experimental paradigms showing how early-life stress is related to hypothalamic-pituitary-adrenal axis function and psychological state in adulthood, and how that relationship can be modulated by other factors. Discussion The risk for adult psychopathology and hypothalamic-pituitary-adrenal axis dysfunction is related to a complex interaction among multiple experiential factors, as well as to susceptibility genes that interact with those factors. Although acute hypothalamic-pituitary-adrenal axis responses to stress are generally adaptive, excessive responses can lead to deleterious effects. Early-life stress alters hypothalamic-pituitary-adrenal axis function and behavior, but the pattern of hypothalamic-pituitary-adrenal dysfunction and psychological outcome in adulthood reflect both the characteristics of the stressor and other modifying factors. Conclusion Research to date has identified multiple determinants of the hypothalamic-pituitary-adrenal axis dysfunction seen in adults with a history of childhood maltreatment or other early-life stress. Further work is needed to establish whether hypothalamic-pituitary-adrenal axis abnormalities in this context can be used to develop risk endophenotypes for psychiatric and physical illnesses. PMID:19967199

The effect of ball impact location on racket and forearm joint angle changes for one-handed tennis backhand groundstrokes.

PubMed

King, Mark; Hau, Agnes; Blenkinsop, Glen

2017-07-01

Recreational tennis players tend to have higher incidence of tennis elbow, and this has been hypothesised to be related to one-handed backhand technique and off-centre ball impacts on the racket face. This study aimed to investigate for a range of participants the effect of off-longitudinal axis and off-lateral axis ball-racket impact locations on racket and forearm joint angle changes immediately following impact in one-handed tennis backhand groundstrokes. Three-dimensional racket and wrist angular kinematic data were recorded for 14 university tennis players each performing 30 "flat" one-handed backhand groundstrokes. Off-longitudinal axis ball-racket impact locations explained over 70% of the variation in racket rotation about the longitudinal axis and wrist flexion/extension angles during the 30 ms immediately following impact. Off-lateral axis ball-racket impact locations had a less clear cut influence on racket and forearm rotations. Specifically off-longitudinal impacts below the longitudinal axis forced the wrist into flexion for all participants with there being between 11° and 32° of forced wrist flexion for an off-longitudinal axis impact that was 1 ball diameter away from the midline. This study has confirmed that off-longitudinal impacts below the longitudinal axis contribute to forced wrist flexion and eccentric stretch of the wrist extensors and there can be large differences in the amount of forced wrist flexion from individual to individual and between strokes with different impact locations.

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...

Spin-stabilized magnetic levitation without vertical axis of rotation

DOEpatents

Romero, Louis [Albuquerque, NM; Christenson, Todd [Albuquerque, NM; Aaronson, Gene [Albuquerque, NM

2009-06-09

The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

Seismicity and state of stress near the Japan Trench axis off Miyagi, northeast Japan, after the 2011 Tohoku-Oki earthquake

NASA Astrophysics Data System (ADS)

Obana, K.; Kodaira, S.; Takahashi, T.; Yamamoto, Y.; Nakamura, Y.; No, T.; Fujie, G.; Hino, R.; Shinohara, M.

2013-12-01

The 2011 Tohoku-Oki earthquake ruptured roughly 200 km wide and 500 km long megathrust along the Japan Trench. The rupture propagated to the trench axis with a maximum slip about 50 m near the trench axis. As a consequence of this large near-trench slip, earthquakes have been activated near the axis of the Japan Trench off Miyagi, northeast Japan. We have conducted ocean bottom seismograph (OBS) experiments in the Japan Trench axis area, surrounding area of the IODP JFAST drilling site, since the occurrence of the 2011 Tohoku-Oki earthquake. Although conventionally used OBS cannot be deployed at seafloor deeper than 6000 m water depth, we used newly developed ultra-deep OBS using ceramic sphere, which can be deployed at a depth of 9000 m, for the observations in the trench axis. The ultra-deep OBS has almost equivalent dimensions and weight with the conventionally used OBS, thus we can handle it in the same manner with the conventionally OBS without any special operation. As a result of a series of the OBS observations, we obtained accurate hypocenter locations and focal mechanisms in both seaward and landward of the trench axis. Earthquakes near the trench axis area were located within the overriding and incoming/subducting plates with very few on the plate interface below the inner trench slope landward of the trench axis. Most of the earthquakes both in the overriding and incoming/subducting plates having normal or strike-slip faulting focal mechanisms with T-axis normal to the trench axis. This indicates that tensional stress is dominant in the trench axis area. However, most seaward part of the seismicity within the overriding plate is characterized by a localized cluster of trench-normal compressional earthquakes, which may relate to spatial variation of the frictional behavior of the shallowest part of the megathrust. On the other hand, trench-normal extensional earthquakes in the incoming/subducting Pacific plate were located at depths shallower than about 35 to 40 km. The deepest trench-normal extensional earthquake observed during OBS observations from December 2012 to January 2013 is slightly shallower than that observed from May to June in 2011 but further observations are required to investigate the temporal change. Continued and repeated earthquake observations could provide information on post-seismic behavior of the megathrust and recovery process of the stress state.

Coordinate measuring system

DOEpatents

Carlisle, Keith [Discovery Bay, CA

2003-04-08

An apparatus and method is utilized to measure relative rigid body motion between two bodies by measuring linear motion in the principal axis and linear motion in an orthogonal axis. From such measurements it is possible to obtain displacement, departure from straightness, and angular displacement from the principal axis of a rigid body.

Late Presentation of a Type III Axis Fracture with Spondyloptosis

PubMed Central

Jayakumar, Prakash; Choi, David; Casey, Adrian

2008-01-01

A 58-year-old man presented with an undiagnosed Effendi type III classification fracture and spondyloptosis of the axis with remarkably normal neurology. We discuss his surgery 4 years since the initial injury, and the presentation, features and management of fractures of the axis. PMID:18430325

Charcterization of the Hypothalamic-Pituitary-Adrenal Axis Response to Atrazine and Metabolites in the Female Rat

EPA Science Inventory

Atrazine (ATR) has recently been shown to activate the hypothalamic-pituitary-adrenal (HPA) axis in rodents. The current study investigated the effect of ATR and two of its chlorinated metabolites, desisopropylatrazine (DIA) and diamino-s-chlorotriazine (DACT), on the HPA axis in...

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.

A local-circulation model for Darrieus vertical-axis wind turbines

NASA Astrophysics Data System (ADS)

Masse, B.

1986-04-01

A new computational model for the aerodynamics of the vertical-axis wind turbine is presented. Based on the local-circulation method generalized for curved blades, combined with a wake model for the vertical-axis wind turbine, it differs markedly from current models based on variations in the streamtube momentum and vortex models using the lifting-line theory. A computer code has been developed to calculate the loads and performance of the Darrieus vertical-axis wind turbine. The results show good agreement with experimental data and compare well with other methods.

Dynamic characteristics of triaxial active control magnetic bearing with asymmetric structure

NASA Astrophysics Data System (ADS)

Nakajima, Atsushi; Hirata, Katsuhiro; Niguchi, Noboru; Kato, Masayuki

2018-03-01

Supporting forces of magnetic bearings are lower than those of mechanical bearings. In order to solve these problems, this paper proposes a new three-axis active control magnetic bearing (3-axis AMB) with an asymmetric structure where its rotor is attracted only in one axial direction due to a negative pressure of fluid. Our proposed 3-axis AMB can generate a large suspension force in one axial direction due to the asymmetric structure. The performances of our proposed 3-axis AMB are computed through 3-D finite element analysis.

Software for System for Controlling a Magnetically Levitated Rotor

NASA Technical Reports Server (NTRS)

Morrison, Carlos R. (Inventor)

2004-01-01

In a rotor assembly having a rotor supported for rotation by magnetic bearings, a processor controlled by software or firmware controls the generation of force vectors that position the rotor relative to its bearings in a 'bounce' mode in which the rotor axis is displaced from the principal axis defined between the bearings and a 'tilt' mode in which the rotor axis is tilted or inclined relative to the principal axis. Waveform driven perturbations are introduced to generate force vectors that excite the rotor in either the 'bounce' or 'tilt' modes.

Linear and Non-Linear Response of Liquid and Solid Particles to Energetic Radiation

DTIC Science & Technology

1991-03-11

for particle 2 located on the + x6 axis (perpendicular to the beam propagation axis) one diameter surface-to-surface from particle 1 (i 12 = 4.0, Obd2 ...axis direction. Off is the far field scattering angle relative to the beam propagation axis. Obd2 is the orientation angle of particle 2 relative to...Particle 2 in the Xb - Zb plane and positioned one diameter surface-to-surface from particle 1 (P12 = 4.0). a.) Obd2 = 00, b.) Obd2 = 30 ° , c.) ebd

System for Controlling a Magnetically Levitated Rotor

NASA Technical Reports Server (NTRS)

Morrison, Carlos R. (Inventor)

2006-01-01

In a rotor assembly having a rotor supported for rotation by magnetic bearings, a processor controlled by software or firmware controls the generation of force vectors that position the rotor relative to its bearings in a "bounce" mode in which the rotor axis is displaced from the principal axis defined between the bearings and a "tilt" mode in which the rotor axis is tilted or inclined relative to the principal axis. Waveform driven perturbations are introduced to generate force vectors that excite the rotor in either the "bounce" or "tilt" modes.

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.

Rapid fabrication of miniature lens arrays by four-axis single point diamond machining

PubMed Central

McCall, Brian; Tkaczyk, Tomasz S.

2013-01-01

A novel method for fabricating lens arrays and other non-rotationally symmetric free-form optics is presented. This is a diamond machining technique using 4 controlled axes of motion – X, Y, Z, and C. As in 3-axis diamond micro-milling, a diamond ball endmill is mounted to the work spindle of a 4-axis ultra-precision computer numerical control (CNC) machine. Unlike 3-axis micro-milling, the C-axis is used to hold the cutting edge of the tool in contact with the lens surface for the entire cut. This allows the feed rates to be doubled compared to the current state of the art of micro-milling while producing an optically smooth surface with very low surface form error and exceptionally low radius error. PMID:23481813

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.

The development and testing of a novel cross axis wind turbine

NASA Astrophysics Data System (ADS)

Chong, W. T.; Muzammil, W. K.; Gwani, M.; Wong, K. H.; Fazlizan, A.; Wang, C. T.; Poh, S. C.

2016-06-01

A novel cross axis wind turbine (CAWT) which comprises of a cross axis blades arrangement was presented and investigated experimentally. The CAWT is a new type of wind turbine that extracts wind energy from airflow coming from the horizontal and vertical directions. The wind turbine consists of three vertical blades and six horizontal blades arranged in a cross axis orientation. Hubs in the middle of the CAWT link the horizontal and vertical blades through connectors to form the CAWT. The study used a 45° deflector to guide the oncoming airflow upward (vertical wind direction). The results from the study showed that the CAWT produced significant improvements in power output and rotational speed performance compared to a conventional straight-bladed vertical axis wind turbine (VAWT).

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.

Content-based fused off-axis object illumination direct-to-digital holography

DOEpatents

Price, Jeffery R.

2006-05-02

Systems and methods are described for content-based fused off-axis illumination direct-to-digital holography. A method includes calculating an illumination angle with respect to an optical axis defined by a focusing lens as a function of data representing a Fourier analyzed spatially heterodyne hologram; reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object the object beam incident upon the object at the illumination angle; focusing the reference beam and the object beam at a focal plane of a digital recorder to from the content-based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; and digitally recording the content based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis.

Permanent-magnet switched-flux machine

DOEpatents

Trzynadlowski, Andrzej M.; Qin, Ling

2011-06-14

A permanent-magnet switched-flux (PMSF) device has an outer rotor mounted to a shaft about a central axis extending axially through the PMSF device. First and second pluralities of permanent-magnets (PMs) are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the outer rotor. An inner stator is coupled to the shaft and has i) a stator core having a core axis co-axial with the central axis; and ii) first and second pluralities of stator poles mounted in first and second circles, radially outwardly from the stator core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

Permanent-magnet switched-flux machine

DOEpatents

Trzynadlowski, Andrzej M.; Qin, Ling

2012-02-21

A permanent-magnet switched-flux (PMSF) device has an outer rotor mounted to a shaft about a central axis extending axially through the PMSF device. First and second pluralities of permanent-magnets (PMs) are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the outer rotor. An inner stator is coupled to the shaft and has i) a stator core having a core axis co-axial with the central axis; and ii) first and second pluralities of stator poles mounted in first and second circles, radially outwardly from the stator core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

Accuracy and repeatability positioning of high-performancel athe for non-circular turning

NASA Astrophysics Data System (ADS)

Majda, Paweł; Powałka, Bartosz

2017-11-01

This paper presents research on the accuracy and repeatability of CNC axis positioning in an innovative lathe with an additional Xs axis. This axis is used to perform movements synchronized with the angular position of the main drive, i.e. the spindle, and with the axial feed along the Z axis. This enables the one-pass turning of non-circular surfaces, rope and trapezoidal threads, as well as the surfaces of rotary tools such as a gear cutting hob, etc. The paper presents and discusses the interpretation of results and the calibration effects of positioning errors in the lathe's numerical control system. Finally, it shows the geometric characteristics of the rope thread turned at various spindle speeds, including before and after-correction of the positioning error of the Xs axis.

Toggle mechanism for pinching metal tubes

NASA Technical Reports Server (NTRS)

Stengard, E. O. (Inventor)

1979-01-01

A toggle mechanism pinches a metal tube and maintains the tube in a pinched condition, without fracturing. The toggle mechanism includes a plunger translatable along a longitudinal axis, as well as a pair of links pivoted about a common axis extending through an end of the plunger. One of the links also pivots about a fixed axis. A free end of the other link carries a push link which the other link translates at right angles to the plunger longitudinal axis. First and second sides of the tube bear against a first stop block and are engaged by the push link when a compression spring, attached to the plunger, is suddenly released to irreversibly drive the plunger along its longitudinal axis so the pivot point of the two links is driven to an over travel position.

DSM-IV Axis II personality disorders and suicide and attempted suicide in China.

PubMed

Tong, Yongsheng; Phillips, Michael R; Conner, Kenneth R

2016-10-01

There are meagre data on Axis II personality disorders and suicidal behaviour in China. To describe the prevalence of Axis II personality disorders in suicides and suicide attempts in China and to estimate risk for these outcomes associated with personality disorders. People who died by suicide (n = 151), people who attempted suicide (n = 118) and living community controls (n = 140) were randomly sampled from four Chinese counties and studied using the Structured Clinical Interviews for DSM-IV-TR Axis I Disorders (SCID-I) and Axis II Personality Disorders (SCID-II). We also determined the prevalence of subthreshold versions of ten DSM-IV personality disorders. Axis II personality disorders were present in 7% of the suicide group, 6% of the suicide attempt group and 1% of the control group. Threshold and subthreshold personality disorders had adjusted odds ratios (point estimates) in the range of 2.7-8.0 for suicide and for suicide attempts. Axis II personality disorders may confer increased risk for suicidal behaviour in China, but their low prevalence in the community and among people with suicidal behaviour suggests that other personality constructs such as select dimensional traits may be a more fruitful avenue for understanding and preventing suicide in China. © The Royal College of Psychiatrists 2016.

The A/P axis in echinoderm ontogeny and evolution: evidence from fossils and molecules

NASA Technical Reports Server (NTRS)

Peterson, K. J.; Arenas-Mena, C.; Davidson, E. H.

2000-01-01

Even though echinoderms are members of the Bilateria, the location of their anterior/posterior axis has remained enigmatic. Here we propose a novel solution to the problem employing three lines of evidence: the expression of a posterior class Hox gene in the coeloms of the nascent adult body plan within the larva; the anatomy of certain early fossil echinoderms; and finally the relation between endoskeletal plate morphology and the associated coelomic tissues. All three lines of evidence converge on the same answer, namely that the location of the adult mouth is anterior, and the anterior/posterior axis runs from the mouth through the adult coelomic compartments. This axis then orients the animal such that there is but a single plane of symmetry dividing the animal into left and right halves. We tentatively hypothesize that this plane of symmetry is positioned along the dorsal/ventral axis. These axis identifications lead to the conclusion that the five ambulacra are not primary body axes, but instead are outgrowths from the central anterior/posterior axis. These identifications also shed insight into several other evolutionary mysteries of various echinoderm clades such as the independent evolution of bilateral symmetry in irregular echinoids, but do not elucidate the underlying mechanisms of the adult coelomic architecture.

β-Catenin is essential for patterning the maternally specified animal-vegetal axis in the sea urchin embryo

PubMed Central

Wikramanayake, Athula H.; Huang, Ling; Klein, William H.

1998-01-01

In sea urchin embryos, the animal-vegetal axis is specified during oogenesis. After fertilization, this axis is patterned to produce five distinct territories by the 60-cell stage. Territorial specification is thought to occur by a signal transduction cascade that is initiated by the large micromeres located at the vegetal pole. The molecular mechanisms that mediate the specification events along the animal–vegetal axis in sea urchin embryos are largely unknown. Nuclear β-catenin is seen in vegetal cells of the early embryo, suggesting that this protein plays a role in specifying vegetal cell fates. Here, we test this hypothesis and show that β-catenin is necessary for vegetal plate specification and is also sufficient for endoderm formation. In addition, we show that β-catenin has pronounced effects on animal blastomeres and is critical for specification of aboral ectoderm and for ectoderm patterning, presumably via a noncell-autonomous mechanism. These results support a model in which a Wnt-like signal released by vegetal cells patterns the early embryo along the animal–vegetal axis. Our results also reveal similarities between the sea urchin animal–vegetal axis and the vertebrate dorsal–ventral axis, suggesting that these axes share a common evolutionary origin. PMID:9689082

Pick-and-place process for sensitivity improvement of the capacitive type CMOS MEMS 2-axis tilt sensor

NASA Astrophysics Data System (ADS)

Chang, Chun-I.; Tsai, Ming-Han; Liu, Yu-Chia; Sun, Chih-Ming; Fang, Weileun

2013-09-01

This study exploits the foundry available complimentary metal-oxide-semiconductor (CMOS) process and the packaging house available pick-and-place technology to implement a capacitive type micromachined 2-axis tilt sensor. The suspended micro mechanical structures such as the spring, stage and sensing electrodes are fabricated using the CMOS microelectromechanical systems (MEMS) processes. A bulk block is assembled onto the suspended stage by pick-and-place technology to increase the proof-mass of the tilt sensor. The low temperature UV-glue dispensing and curing processes are employed to bond the block onto the stage. Thus, the sensitivity of the CMOS MEMS capacitive type 2-axis tilt sensor is significantly improved. In application, this study successfully demonstrates the bonding of a bulk solder ball of 100 µm in diameter with a 2-axis tilt sensor fabricated using the standard TSMC 0.35 µm 2P4M CMOS process. Measurements show the sensitivities of the 2-axis tilt sensor are increased for 2.06-fold (x-axis) and 1.78-fold (y-axis) after adding the solder ball. Note that the sensitivity can be further improved by reducing the parasitic capacitance and the mismatch of sensing electrodes caused by the solder ball.

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.

Propagation of Ince-Gaussian beams in uniaxial crystals orthogonal to the optical axis

NASA Astrophysics Data System (ADS)

Xu, Y. Q.; Zhou, G. Q.

2012-03-01

An analytical propagation expression of an Ince-Gaussian beam in uniaxial crystals orthogonal to the optical axis is derived. The uniaxial crystal considered here has the property of the extraordinary refractive index being larger than the ordinary refractive index. The Ince-Gaussian beam in the transversal direction along the optical axis spreads more rapidly than that in the other transversal direction. With increasing the ratio of the extraordinary refractive index to the ordinary refractive index, the spreading of the Ince-Gaussian beam in the transversal direction along the optical axis increases and the spreading of the Ince-Gaussian beam in the other transversal direction decreases. The effective beam size in the transversal direction along the optical axis is always larger than that in the other transversal direction. When the even and odd modes of Ince-Gaussian beams exist simultaneously, the effective beam size in the direction along the optical axis of the odd Ince-Gaussian beam is smaller than that of the even Ince-Gaussian beam in the corresponding direction, and the effective beam size in the transversal direction orthogonal to the optical axis of the odd Ince-Gaussian beam is larger than that of the even Ince-Gaussian beam in the corresponding direction.

Experimental Study on Voided Reinforced Concrete Beams with Polythene Balls

NASA Astrophysics Data System (ADS)

Sivaneshan, P.; Harishankar, S.

2017-07-01

The primary component in any structure is concrete, that exist in buildings and bridges. In present situation, a serious problems faced by construction industry is exhaustive use of raw materials. Recent times, various methods are being adopted to limit the use of concrete. In structural elements like beams, polythene balls can be induced to reduce the usage of concrete. A simply supported reinforced concrete beam has two zones, one above neutral axis and other below neutral axis. The region below neutral axis is in tension and above neutral axis is in compression. As concrete is weak in tension, steel reinforcements are provided in tension zone. The concrete below the neutral axis acts as a stress transfer medium between the compression zone and tension zone. The concrete above the neutral axis takes minimum stress so that we could partially replace the concrete above neutral axis by creating air voids using recycled polythene balls. Polythene balls of varying diameters of 75 mm, 65 mm and 35 mm were partially replaced in compression zone. Hence the usage of concrete in beams and self-weight of the beams got reduced considerably. The Load carrying capacity, Deflection of beams and crack patterns were studied and compared with conventional reinforced concrete beams.

Engineering the on-axis intensity of Bessel beam by a feedback tuning loop

NASA Astrophysics Data System (ADS)

Li, Runze; Yu, Xianghua; Yang, Yanlong; Peng, Tong; Yao, Baoli; Zhang, Chunmin; Ye, Tong

2018-02-01

The Bessel beam belongs to a typical class of non-diffractive optical fields that are characterized by their invariant focal profiles along the propagation direction. However, ideal Bessel beams only rigorously exist in theory; Bessel beams generated in the lab are quasi-Bessel beams with finite focal extensions and varying intensity profiles along the propagation axis. The ability to engineer the on-axis intensity profile to the desired shape is essential for many applications. Here we demonstrate an iterative optimization-based approach to engineering the on-axis intensity of Bessel beams. The genetic algorithm is used to demonstrate this approach. Starting with a traditional axicon phase mask, in the design process, the computed on-axis beam profile is fed into a feedback tuning loop of an iterative optimization process, which searches for an optimal radial phase distribution that can generate a generalized Bessel beam with the desired onaxis intensity profile. The experimental implementation involves a fine-tuning process that adjusts the originally targeted profile so that the optimization process can optimize the phase mask to yield an improved on-axis profile. Our proposed method has been demonstrated in engineering several zeroth-order Bessel beams with customized on-axis profiles. High accuracy and high energy throughput merit its use in many applications.

An immediate effect of axial neck rotation training with real time visual feedback using a smartphone inclinometer on improvement in axial neck rotation function.

PubMed

Park, Kyue-Nam; Kwon, Oh-Yun; Kim, Si-Hyun; Jeon, In-Cheol

2017-03-01

The purpose of this study was to compare the immediate effects of axial neck rotation training (Axi-NRT) with and without real-time visual feedback (VF) using a smartphone inclinometer on the range of motion (ROM) for axial neck rotation and the onset of compensatory neck lateral bending and extension during active neck rotation. Twenty participants with restricted ROM for neck rotation but no neck pain (21.1 ± 1.6 years and 8 males, 12 females) were recruited for Axi-NRT with VF, and twenty age- and gender-matched participants with restricted ROM for neck rotation were recruited for Axi-NRT without VF. Changes in ROM for neck rotation and the onset time of compensatory neck movement during active neck rotation were measured using an electromagnetic tracking system. Axi-NRT with VF was more effective in increasing ROM for neck rotation and decreasing and delaying the onset of compensatory neck movements during active neck rotation compared with Axi-NRT without VF. Repeated Axi-NRT using VF is useful to educate participants in maintaining the axis of the cervical spine and to increase ROM for axial neck rotation with less compensatory neck motion in participants with a restricted range of neck rotations.

Micro-CT Evaluation of Ceramic Inlays: Comparison of the Marginal and Internal Fit of Five and Three Axis CAM Systems with a Heat Press Technique.

PubMed

Alajaji, Norah K; Bardwell, David; Finkelman, Matthew; Ali, Ala

2017-02-01

To evaluate the marginal and internal adaptation of CAD/CAM lithium-disilicate inlay restorations fabricated by two milling systems (Five and Three-axis), and a traditional heat-press technique. Fifteen premolar teeth with an MOD cavity preparation were fabricated. Lithium-disilicate inlay restorations were obtained by three fabrication techniques and fitted to their dies (n = 15/gp) as follows: Group-1, three-axis milling system, Group-2, five-axis milling system, Group-3, conventional heat-press technique. Gaps were evaluated by X-ray microtomography. Marginal gap (MG), occlusal-marginal gap (OMG), proximal-marginal gap (PMG), gingival-marginal gap (GMG), absolute marginal discrepancy (AMD), axial-internal gap (AIG), and occlusal-internal gap (OIG) were evaluated at 120 different points per inlay. Data were analyzed using repeated measures ANOVA. Pairwise comparisons were conducted for post-hoc testes and the Bonferroni correction was used to adjust for multiple comparisons (α = 0.007). The heat-press group demonstrated significantly smaller mean-values amongst all outcomes compared with CAD/CAM groups except for GMG, where there was no statistically significant difference between groups in the ANOVA (p = 0.042). Within the CAD/CAM groups, the five-axis group showed significantly lower OMG mean-value compared with the three-axis group p < 0.001, and lower AIG mean-value compared with the three-axis group p < 0.001. There was no significant difference between the five-axis and the three-axis groups' AMD, MG, PMG, and OIG locations. Different fabrication techniques affected the marginal and internal adaptation of ceramic inlay restorations. The heat-press group showed the best marginal and internal adaptation results; however, in every group, all samples were within the clinically acceptable MG limit (100 μm). The marginal fit and internal adaptation of inlay ceramic restorations fabricated by a five-axis milling system have not been tested or compared with those fabricated by three-axis machines and the conventional heat-press method. The preferred method of inlay fabrication, whether in the lab or chair side, may be influenced by the results of this study and could affect future clinical decision-making. (J Esthet Restor Dent 29:49-58, 2017). © 2016 Wiley Periodicals, Inc.

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

Qing-He, Gao; Information Engineering College, Liaoning University of Traditional Chinese Medicine, Shenyang 110847; Zhi-Jun, Xu

The mechanical properties and structural evolution of Mo{sub 2}GaC are calculated by first-principles under pressure. Our results unexpectedly found that the c axis is always stiffer than a axis within 0–100 GPa. An ultraincompressibility of c axis within 15–60 GPa is observed, with a contraction of about 0.2 Å, slightly larger than that of a axis (0.14 Å). The abnormal expansion of c axis and the fast decrease in a axis above about 15 GPa and 70 GPa failed to induce the structural instability, whereas such behavior caused the elastic softening in many mechanical quantities. The shrinkage anomaly of c axis is closely reflected by themore » internal coordinate (u) shift of Mo atom as it shows three different slopes within 0–15 GPa, 20–60 GPa, and 70–100 GPa, respectively. The longest Mo-Mo bond is responsible for the unusual shrinkage of c-axis under pressure as they experience nearly identical pressure dependences, whereas the a axis presents certain response with the variation of C-Mo bond particularly at 70 GPa. The electronic properties are investigated, including the energy band and density of states, and so on. At G point of K-M line, the energy decreases at 10 GPa first and increases at 30 GPa subsequently, the critical point is at about 15 GPa, with respective values of −0.17 of 0 GPa, −0.18 of 10 GPa, −0.16 of 15 GPa, and −0.13 of 30 GPa, respectively. This alternative energy change of G point, which is the symmetry center of the rhombic parallelogram of Ga atoms and the midpoint of the two bonded Mo atoms, convincingly reveal the origin of the anomalous ultraincompressibility of c axis as the Mo-Mo bond length shrinkage has to overcome the increasing energy barrier height. The Mo-Mo bond population and the electronegativity investigations of the Mo atom further reveal the most likely origin of the ultraincompressibility of c axis. This interesting result expects further experimental confirmation as this is the first nanolaminate ceramics compound presenting quite low-pressure axial ultraincompressibility.« less

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

Exposure to stress during critical periods in development can have severe long-term consequences, increasing overall risk on psychopathology. One of the key stress response systems mediating these long-term effects of stress is the hypothalamic-pituitary-adrenal (HPA) axis; a cascade of central and peripheral events resulting in the release of corticosteroids from the adrenal glands. Activation of the HPA-axis affects brain functioning to ensure a proper behavioral response to the stressor, but stress-induced (mal)adaptation of the HPA-axis' functional maturation may provide a mechanistic basis for the altered stress susceptibility later in life. Development of the HPA-axis and the brain regions involved in its regulation starts prenatally and continues after birth, and is protected by several mechanisms preventing corticosteroid over-exposure to the maturing brain. Nevertheless, early life stress (ELS) exposure has been reported to have numerous consequences on HPA-axis function in adulthood, affecting both its basal and stress-induced activity. According to the match/mismatch theory, encountering ELS prepares an organism for similar (“matching”) adversities during adulthood, while a mismatching environment results in an increased susceptibility to psychopathology, indicating that ELS can exert either beneficial or disadvantageous effects depending on the environmental context. Here, we review studies investigating the mechanistic underpinnings of the ELS-induced alterations in the structural and functional development of the HPA-axis and its key external regulators (amygdala, hippocampus, and prefrontal cortex). The effects of ELS appear highly dependent on the developmental time window affected, the sex of the offspring, and the developmental stage at which effects are assessed. Albeit by distinct mechanisms, ELS induced by prenatal stressors, maternal separation, or the limited nesting model inducing fragmented maternal care, typically results in HPA-axis 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 novel verification method using a plastic scintillator imagining system for assessment of gantry sag in radiotherapy.

PubMed

Tsuneda, Masato; Nishio, Teiji; Saito, Akito; Tanaka, Sodai; Suzuki, Tatsuhiko; Kawahara, Daisuke; Matsushita, Keiichiro; Nishio, Aya; Ozawa, Shuichi; Karasawa, Kumiko; Nagata, Yasushi

2018-06-01

High accuracy of the beam-irradiated position is required for high-precision radiation therapy such as stereotactic body radiation therapy (SBRT), volumetric modulated arc therapy (VMAT), and intensity modulated radiation therapy (IMRT). Users generally perform the verification of the mechanical and radiation isocenters using the star shot test and the Winston Lutz test that allow evaluation of the displacement at the isocenter. However, these methods are unable to evaluate directly and quantitatively the sagging angle that is caused by the weight of the gantry itself along the gantry rotation axis. In addition, the verification of the central axis of the irradiated beam that is not dependent at the isocenter is needed for the mechanical quality assurance of a nonisocentric irradiation technique. In this study, we have developed a prototype system for the verification of three-dimensional (3D) beam alignment and we have verified the system concept for 3D isocentricity. Our system allows detection of the central axis in 3D coordinates and evaluation of the irradiated oblique angle to the gantry rotation axis, i.e., the sagging angle. In order to measure the central axis of the irradiated beam in 3D coordinates, we constructed the prototype verification system consisting of a column-shaped plastic scintillator (CoPS), a truncated cone-shaped mirror (TCsM), and a cooled charged-coupled device (CCD) camera. This verification system was irradiated with 6-MV photon beams and the scintillation light was measured using the CCD camera. The central axis on the axial plane (two-dimensional (2D) central axis) was acquired from the integration of the scintillation light along the major axis of the CoPS, and the central axis in 3D coordinates (3D central axis) was acquired from two curve-shaped profiles which were reflected by the TCsM. We verified the calculation accuracy of the gantry rotation axis, θ z . Additionally, we calculated the 3D central axis and the sagging angle at each gantry angle. We acquired the measurement images composed of the 2D central axis and the two curve-shaped profiles. The relationship between the irradiated and measured angles with respect to the gantry rotation axis had good linearity. The mean and standard deviation of the difference between the irradiated and measured angles were 0.012 and 0.078 degrees, respectively. The size of the 2D and 3D radiation isocenters were 0.470 and 0.652 mm on the axial plane and in 3D coordinates, respectively. The sagging angles were -0.31, 0.39, and 0.38 degrees at the gantry angles of 0, 180, and 180E degrees, respectively. We developed a novel verification system, designated as the "kompeito shot test system," to verify the 3D beam alignment. This system concept works for both verification of the 3D isocentricity and the direct evaluation of the sagging angle. Next, we want to improve the aspects of this system, such as the shape and the type of scintillator, to increase the system accuracy and nonisocentric beam alignment performance. © 2018 American Association of Physicists in Medicine.

Power-Factor and Torque Calculation under Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation

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

Lee, Seong T; Burress, Timothy A; Tolbert, Leon M

2009-01-01

This paper introduces a new method for calculating the power factor and output torque by considering the cross saturation between direct-axis (d-axis) and quadrature-axis (q-axis) of an interior permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include the cross saturation effect by adding the cross-coupled inductance terms. This paper also contains the new method of calculating the cross-coupled inductance values as well as self-inductance values in d- and q-axes. The analyzed motor is a high-speed brushless field excitation machine that offers high torque per ampere per core length at low speed and weakened flux atmore » high speed, which was developed for the traction motor of a hybrid electric vehicle. The conventional two-axis IPMSM model was modified to include the cross-saturation effect by adding the cross-coupled inductance terms Ldq and Lqd. By the advantage of the excited structure of the experimental IPMSM, the analyzing works were performed under two conditions, the highest and lowest excited conditions. Therefore, it is possible to investigate the cross-saturation effect when a machine has higher magnetic flux from its rotor. The following is a summary of conclusions that may be drawn from this work: (1) Considering cross saturation of an IPMSM offers more accurate expected values of motor parameters in output torque calculation, especially when negative d-axis current is high; (2) A less saturated synchronous machine could be more affected by the cross-coupled saturation effect; (3) Both cross-coupled inductances, L{sub qd} and L{sub dq}, are mainly governed by d-axis current rather than q-axis current; (4) The modified torque equation, can be used for the dynamic model of an IPMSM for developing a better control model or control strategy; and (5) It is possible that the brushless field excitation structure has a common magnetic flux path on both d- and q-axis, and as a result, the reluctance torque of the machine could be reduced.« less

Accuracy of right and left ventricular functional assessment by short-axis vs axial cine steady-state free-precession magnetic resonance imaging: intrapatient correlation with main pulmonary artery and ascending aorta phase-contrast flow measurements.

PubMed

James, Susan H; Wald, Rachel; Wintersperger, Bernd J; Jimenez-Juan, Laura; Deva, Djeven; Crean, Andrew M; Nguyen, Elsie; Paul, Narinder S; Ley, Sebastian

2013-08-01

The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations. A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output. There was a high linear correlation between MPA-PC flow and RV-stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and -2.3 mL for RV-short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis-LV SV and short-axis-RV SV. No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes. Copyright © 2013 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Identification of minute damage in composite bridge structures equipped with fiber optic sensors using the location of neutral axis and finite element analysis

NASA Astrophysics Data System (ADS)

Li, Xi; Glisic, Branko

2016-04-01

By definition, the neutral axis of a loaded composite beam structure is the curve along which the section experiences zero bending strain. When no axial loading is present, the location of the neutral axis passes through the centroid of stiffness of the beam cross-section. In the presence of damage, the centroid of stiffness, as well as the neutral axis, shift from the healthy position. The concept of neutral axis can be widely applied to all beam-like structures. According to literature, a change in location of the neutral axis can be associated with damage in the corresponding cross-section. In this paper, the movement of neutral axis near locations of minute damage in a composite bridge structure was studied using finite element analysis and experimental results. The finite element model was developed based on a physical scale model of a composite simply-supported structure with controlled minute damage in the reinforced concrete deck. The structure was equipped with long-gauge fiber optic strain and temperature sensors at a healthy reference location as well as two locations of damage. A total of 12 strain sensors were installed during construction and used to monitor the structure during various loading events. This paper aims to explain previous experimental results which showed that the observed positions of neutral axis near damage locations were higher than the predicted healthy locations in some loading events. Analysis has shown that finite element analysis has potential to simulate and explain the physical behavior of the test structure.

Hypothalamic-Pituitary-Adrenal Hypofunction in Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) as a Consequence of Activated Immune-Inflammatory and Oxidative and Nitrosative Pathways.

PubMed

Morris, Gerwyn; Anderson, George; Maes, Michael

2017-11-01

There is evidence that immune-inflammatory and oxidative and nitrosative stress (O&NS) pathways play a role in the pathophysiology of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). There is also evidence that these neuroimmune diseases are accompanied by hypothalamic-pituitary-adrenal (HPA) axis hypoactivity as indicated by lowered baseline glucocorticoid levels. This paper aims to review the bidirectional communications between immune-inflammatory and O&NS pathways and HPA axis hypoactivity in ME/CFS, considering two possibilities: (a) Activation of immune-inflammatory pathways is secondary to HPA axis hypofunction via attenuated negative feedback mechanisms, or (b) chronic activated immune-inflammatory and O&NS pathways play a causative role in HPA axis hypoactivity. Electronic databases, i.e., PUBMED, Scopus, and Google Scholar, were used as sources for this narrative review by using keywords CFS, ME, cortisol, ACTH, CRH, HPA axis, glucocorticoid receptor, cytokines, immune, immunity, inflammation, and O&NS. Findings show that activation of immune-inflammatory and O&NS pathways in ME/CFS are probably not secondary to HPA axis hypoactivity and that activation of these pathways may underpin HPA axis hypofunction in ME/CFS. Mechanistic explanations comprise increased levels of tumor necrosis factor-α, T regulatory responses with elevated levels of interleukin-10 and transforming growth factor-β, elevated levels of nitric oxide, and viral/bacterial-mediated mechanisms. HPA axis hypoactivity in ME/CFS is most likely a consequence and not a cause of a wide variety of activated immune-inflammatory and O&NS pathways in that illness.

Design, Fabrication, and Modeling of a Novel Dual-Axis Control Input PZT Gyroscope.

PubMed

Chang, Cheng-Yang; Chen, Tsung-Lin

2017-10-31

Conventional gyroscopes are equipped with a single-axis control input, limiting their performance. Although researchers have proposed control algorithms with dual-axis control inputs to improve gyroscope performance, most have verified the control algorithms through numerical simulations because they lacked practical devices with dual-axis control inputs. The aim of this study was to design a piezoelectric gyroscope equipped with a dual-axis control input so that researchers may experimentally verify those control algorithms in future. Designing a piezoelectric gyroscope with a dual-axis control input is more difficult than designing a conventional gyroscope because the control input must be effective over a broad frequency range to compensate for imperfections, and the multiple mode shapes in flexural deformations complicate the relation between flexural deformation and the proof mass position. This study solved these problems by using a lead zirconate titanate (PZT) material, introducing additional electrodes for shielding, developing an optimal electrode pattern, and performing calibrations of undesired couplings. The results indicated that the fabricated device could be operated at 5.5±1 kHz to perform dual-axis actuations and position measurements. The calibration of the fabricated device was completed by system identifications of a new dynamic model including gyroscopic motions, electromechanical coupling, mechanical coupling, electrostatic coupling, and capacitive output impedance. Finally, without the assistance of control algorithms, the "open loop sensitivity" of the fabricated gyroscope was 1.82 μV/deg/s with a nonlinearity of 9.5% full-scale output. This sensitivity is comparable with those of other PZT gyroscopes with single-axis control inputs.

Binocular Coordination of the Human Vestibulo-Ocular Reflex during Off-axis Pitch Rotation

NASA Technical Reports Server (NTRS)

Wood, S. J.; Reschke, M. F.; Kaufman, G. D.; Black, F. O.; Paloski, W. H.

2006-01-01

Head movements in the sagittal pitch plane typically involve off-axis rotation requiring both vertical and horizontal vergence ocular reflexes to compensate for angular and translational motion relative to visual targets of interest. The purpose of this study was to compare passive pitch VOR responses during rotation about an Earth-vertical axis (canal only cues) with off-axis rotation (canal and otolith cues). Methods. Eleven human subjects were oscillated sinusoidally at 0.13, 0.3 and 0.56 Hz while lying left-side down with the interaural axis either aligned with the axis of rotation or offset by 50 cm. In a second set of measurements, twelve subjects were also tested during sinusoidally varying centrifugation over the same frequency range. The modulation of vertical and horizontal vergence ocular responses was measured with a binocular videography system. Results. Off-axis pitch rotation enhanced the vertical VOR at lower frequencies and enhanced the vergence VOR at higher frequencies. During sinusoidally varying centrifugation, the opposite trend was observed for vergence, with both vertical and vergence vestibulo-ocular reflexes being suppressed at the highest frequency. Discussion. These differential effects of off-axis rotation over the 0.13 to 0.56 Hz range are consistent with the hypothesis that otolith-ocular reflexes are segregated in part on the basis of stimulus frequency. At the lower frequencies, tilt otolith-ocular responses compensate for declining canal input. At higher frequencies, translational otolith-ocular reflexes compensate for declining visual contributions to the kinematic demands required for fixating near targets.

Combined pitch and roll and cybersickness in a virtual environment.

PubMed

Bonato, Frederick; Bubka, Andrea; Palmisano, Stephen

2009-11-01

Stationary subjects who perceive visually induced illusions of self-motion, or vection, in virtual reality (VR) often experience cybersickness, the symptoms of which are similar to those experienced during motion sickness. An experiment was conducted to test the effects of single and dual-axis rotation of a virtual environment on cybersickness. It was predicted that VR displays which induced illusory dual-axis (as opposed to single-axis) self-rotations in stationary subjects would generate more sensory conflict and subsequently more cybersickness. There were 19 individuals (5 men, 14 women, mean age = 19.8 yr) who viewed the interior of a virtual cube that steadily rotated (at 60 degrees x s(-1)) about either the pitch axis or both the pitch and roll axes simultaneously. Subjects completed the Simulator Sickness Questionnaire (SSQ) before a trial and after 5 min of stimulus viewing. Post-treatment total SSQ scores and subscores for nausea, oculomotor, and disorientation were significantly higher in the dual-axis condition. These results support the hypothesis that a vection-inducing VR stimulus that rotates about two axes generates more cybersickness compared to aVR stimulus that rotates about only one. In the single-axis condition, sensory conflict and pseudo-Coriolis effects may have led to symptoms. However, in the dual-axis condition, not only was perceived self-motion more complex (two axes compared to one), the inducing stimulus was consistent with twice as much self-motion. Hence, the increased likelihood/magnitude of sensory conflict and pseudo-Coriolis effects may have subsequently resulted in a higher degree of cybersickness in the dual-axis condition.

Cervical helical axis characteristics and its center of rotation during active head and upper arm movements-comparisons of whiplash-associated disorders, non-specific neck pain and asymptomatic individuals.

PubMed

Grip, Helena; Sundelin, Gunnevi; Gerdle, Björn; Stefan Karlsson, J

2008-09-18

The helical axis model can be used to describe translation and rotation of spine segments. The aim of this study was to investigate the cervical helical axis and its center of rotation during fast head movements (side rotation and flexion/extension) and ball catching in patients with non-specific neck pain or pain due to whiplash injury as compared with matched controls. The aim was also to investigate correlations with neck pain intensity. A finite helical axis model with a time-varying window was used. The intersection point of the axis during different movement conditions was calculated. A repeated-measures ANOVA model was used to investigate the cervical helical axis and its rotation center for consecutive levels of 15 degrees during head movement. Irregularities in axis movement were derived using a zero-crossing approach. In addition, head, arm and upper body range of motion and velocity were observed. A general increase of axis irregularity that correlated to pain intensity was observed in the whiplash group. The rotation center was superiorly displaced in the non-specific neck pain group during side rotation, with the same tendency for the whiplash group. During ball catching, an anterior displacement (and a tendency to an inferior displacement) of the center of rotation and slower and more restricted upper body movements implied a changed movement strategy in neck pain patients, possibly as an attempt to stabilize the cervical spine during head movement.

Coronal Axis Measurement of the Optic Nerve Sheath Diameter Using a Linear Transducer.

PubMed

Amini, Richard; Stolz, Lori A; Patanwala, Asad E; Adhikari, Srikar

2015-09-01

The true optic nerve sheath diameter cutoff value for detecting elevated intracranial pressure is variable. The variability may stem from the technique used to acquire sonographic measurements of the optic nerve sheath diameter as well as sonographic artifacts inherent to the technique. The purpose of this study was to compare the traditional visual axis technique to an infraorbital coronal axis technique for assessing the optic nerve sheath diameter using a high-frequency linear array transducer. We conducted a cross-sectional study at an academic medical center. Timed optic nerve sheath diameter measurements were obtained on both eyes of healthy adult volunteers with a 10-5-MHz broadband linear array transducer using both traditional visual axis and coronal axis techniques. Optic nerve sheath diameter measurements were obtained by 2 sonologists who graded the difficulty of each technique and were blinded to each other's measurements for each participant. A total of 42 volunteers were enrolled, yielding 84 optic nerve sheath diameter measurements. There were no significant differences in the measurements between the techniques on either eye (P = .23 [right]; P = .99 [left]). Additionally, there was no difference in the degree of difficulty obtaining the measurements between the techniques (P = .16). There was a statistically significant difference in the time required to obtain the measurements between the traditional and coronal techniques (P < .05). Infraorbital coronal axis measurements are similar to measurements obtained in the traditional visual axis. The infraorbital coronal axis technique is slightly faster to perform and is not technically challenging. © 2015 by the American Institute of Ultrasound in Medicine.

A method to determine the orientation of the upper arm about its longitudinal axis during dynamic motions.

PubMed

Gordon, Brian J; Dapena, Jesús

2013-01-04

Inaccuracy in determining the orientation of the upper arm about its longitudinal axis (twist orientation) has been a pervasive problem in sport biomechanics research. The purpose of this study was to develop a method to improve the calculation of the upper arm twist orientation in dynamic sports activities. The twist orientation of the upper arm is defined by the orientation of its mediolateral axis. The basis for the new method is that at any angle in the flexion/extension range of an individual's elbow, it is possible to define a true mediolateral axis and also a surrogate mediolateral axis perpendicular to the plane containing the shoulder, elbow and wrist joints. The difference between the twist orientations indicated by these two versions of the mediolateral axis will vary from one elbow angle to another, but if the elbow joint deforms equally in different activities, for any given subject the difference should be constant at any given value of the elbow angle. Application of the new method required individuals to execute sedate elbow extension trials prior to the dynamic trials. Three-dimensional motion analysis of the sedate extension trials allowed quantification of the difference between the true and surrogate mediolateral axes for all angles in the entire flexion/extension range of an individual's elbow. This made it possible to calculate in any dynamic trial the twist orientation defined by the true mediolateral axis from the twist orientation defined by the surrogate mediolateral axis. The method was tested on a wooden model of the arm. Copyright © 2012 Elsevier Ltd. All rights reserved.

Association Between Pituitary-Adrenal Axis Dominance Over the Renin-Angiotensin-Aldosterone System and Hypertension.

PubMed

Daimon, Makoto; Kamba, Aya; Murakami, Hiroshi; Takahashi, Kazuhisa; Otaka, Hideyuki; Makita, Koushi; Yanagimachi, Miyuki; Terui, Ken; Kageyama, Kazunori; Nigawara, Takeshi; Sawada, Kaori; Takahashi, Ippei; Nakaji, Shigeyuki

2016-03-01

The hypothalamus-pituitary-adrenal (HPA) axis and the renin-angiotensin aldosterone system (RAAS) are well known to be associated with hypertension. However, the extent of the effects is not yet well elucidated in general conditions. To separately determine the effect of the HPA axis and the RAAS on hypertension in a general population. A population-based study of 859 Japanese individuals enrolled in the 2014 Iwaki study and without hypertension or steroid treatment (age, 50.2 ± 14.7 years). Hypertension prevalence, plasma concentration of aldosterone, ACTH, cortisol, and plasma renin activity. Principal component (PC) analysis using these four hormones identified two PCs (PC1 and PC2), which represent levels of these hormones as a whole, and dominance between the HPA axis (ACTH and cortisol) and the RAAS (plasma renin activity and plasma concentration of aldosterone), respectively. Association between these PCs and hypertension was significant (PC1, high vs low, odds ratio [OR], 1.48; 95% confidence interval [CI], 1.09-2.02; and PC2, HPA axis vs RAAS dominancy, OR, 2.08; and 95% CI, 1.51-2.85). However, association between the hormone levels as a whole and hypertension became insignificant after adjustment for multiple factors including these PCs together. However, association between the HPA axis dominance and hypertension remained significant even after the adjustment (the HPA axis vs the RAAS, OR, 1.73; 95% CI, 1.20-2.48). The HPA axis dominance over the RAAS is significantly associated with hypertension in a Japanese population.

Effortful Control and Parenting: Associations with HPA Axis Reactivity in Early Childhood

ERIC Educational Resources Information Center

Kryski, Katie R.; Dougherty, Lea R.; Dyson, Margaret W.; Olino, Thomas M.; Laptook, Rebecca S.; Klein, Daniel N.; Hayden, Elizabeth P.

2013-01-01

While activation of the hypothalamic-pituitary-adrenal (HPA) axis is an adaptive response to stress, excessive HPA axis reactivity may be an important marker of childhood vulnerability to psychopathology. Parenting, including parent affect during parent-child interactions, may play an important role in shaping the developing HPA system; however,…

The intestinal-renal axis for arginine synthesis is present and functional in the neonatal pig

USDA-ARS?s Scientific Manuscript database

The intestinal-renal axis for endogenous arginine synthesis is an interorgan process in which citrulline produced in the small intestine is utilized by the kidney for arginine synthesis. The function of this axis in neonates has been questioned because during this period the enzymes needed for argin...

Axis: Generating Explanations at Scale with Learnersourcing and Machine Learning

ERIC Educational Resources Information Center

Williams, Joseph Jay; Kim, Juho; Rafferty, Anna; Heffernan, Neil; Maldonado, Samuel; Gajos, Krzysztof Z.; Lasecki, Walter S.; Heffernan, Neil

2016-01-01

While explanations may help people learn by providing information about why an answer is correct, many problems on online platforms lack high-quality explanations. This paper presents AXIS (Adaptive eXplanation Improvement System), a system for obtaining explanations. AXIS asks learners to generate, revise, and evaluate explanations as they solve…

Transcriptional regulatory dynamics of the hypothalamic-pituitary-gonadal axis and its peripheral pathways as impacted by the 3-beta HSD inhibitor Trilostane in zebrafish (Danio rerio)

EPA Science Inventory

To identify transcription factors (TFs), members of hypothalamic-pituitary- gonadal axis (HPG-axis), TF networks and signaling pathways underlying generalized effects of 3-beta hydroxysteroid dehydrogenase (HSD3B) inhibition, reproductively mature zebrafish (Danio rerio) were exp...

Congenital axis dysmorphism in a medieval skeleton : …secunda a vertendo epistropheus….

PubMed

Travan, Luciana; Saccheri, Paola; Toso, Francesco; Crivellato, Enrico

2013-05-01

We describe here the axis dysmorphism that we observed in the skeletal remains of a human child dug up from a fifteenth century cemetery located in north-eastern Italy. This bone defect is discussed in the light of pertinent literature. We performed macroscopical examination and CT scan analysis of the axis. Axis structure was remarkably asymmetric. Whilst the left half exhibited normal morphology, the right one was smaller than normal, and its lateral articular surface showed horizontal orientation. In addition, the odontoid process appeared leftward deviated and displayed a supplementary articular-like facet situated on the right side of its surface. These findings suggest a diagnosis of unilateral irregular segmentation of atlas and axis, a rare dysmorphism dependent upon disturbances of notochordal development in early embryonic life. Likewise other malformations of the craniovertebral junction, this axis defect may alter the delicate mechanisms of upper neck movements and cause a complex series of clinical symptoms. This is an emblematic case whereby human skeletal remains may provide valuable information on the anatomical defects of craniovertebral junction.

Quantification of right ventricular volumes and function by real time three-dimensional echocardiographic longitudinal axial plane method: validation in the clinical setting.

PubMed

Endo, Yuka; Maddukuri, Prasad V; Vieira, Marcelo L C; Pandian, Natesa G; Patel, Ayan R

2006-11-01

Measurement of right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) by three-dimensional echocardiographic (3DE) short-axis disc summation method has been validated in multiple studies. However, in some patients, short-axis images are of insufficient quality for accurate tracing of the RV endocardial border. This study examined the accuracy of long-axis analysis in multiple planes (longitudinal axial plane method) for assessment of RV volumes and RVEF. 3DE images were analyzed in 40 subjects with a broad range of RV function. RV end-diastolic (RVEDV) and end-systolic volumes (RVESV) and RVEF were calculated by both short-axis disc summation method and longitudinal axial plane method. Excellent correlation was obtained between the two methods for RVEDV, RVESV, and RVEF (r = 0.99, 0.99, 0.94, respectively; P < 0.0001 for all comparisons). 3DE longitudinal-axis analysis is a promising technique for the evaluation of RV function, and may provide an alternative method of assessment in patients with suboptimal short-axis images.

Double diameter boring tool

DOEpatents

Ashbaugh, F.A.; Murry, K.R.

1986-02-10

A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting flutes formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first flute tip to the axis of rotation plus the distance from the second flute tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second flute tip to the axis of rotation minus one-half the distance from the first flute tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

Estimating the spin axis orientation of the Echostar-2 box-wing geosynchronous satellite

NASA Astrophysics Data System (ADS)

Earl, Michael A.; Somers, Philip W.; Kabin, Konstantin; Bédard, Donald; Wade, Gregg A.

2018-04-01

For the first time, the spin axis orientation of an inactive box-wing geosynchronous satellite has been estimated from ground-based optical photometric observations of Echostar-2's specular reflections. Recent photometric light curves obtained of Echostar-2 over four years suggest that unusually bright and brief specular reflections were occurring twice within an observed spin period. These bright and brief specular reflections suggested two satellite surfaces with surface normals separated by approximately 180°. The geometry between the satellite, the Sun, and the observing location at the time of each of the brightest observed reflections, was used to estimate Echostar-2's equatorial spin axis orientation coordinates. When considering prograde and retrograde rotation, Echostar-2's spin axis orientation was estimated to have been located within 30° of either equatorial coordinate pole. Echostar-2's spin axis was observed to have moved approximately 180° in right ascension, within a time span of six months, suggesting a roughly one year spin axis precession period about the satellite's angular momentum vector.

Broadband quantitative phase microscopy with extended field of view using off-axis interferometric multiplexing.

PubMed

Girshovitz, Pinhas; Frenklach, Irena; Shaked, Natan T

2015-11-01

We propose a new portable imaging configuration that can double the field of view (FOV) of existing off-axis interferometric imaging setups, including broadband off-axis interferometers. This configuration is attached at the output port of the off-axis interferometer and optically creates a multiplexed interferogram on the digital camera, which is composed of two off-axis interferograms with straight fringes at orthogonal directions. Each of these interferograms contains a different FOV of the imaged sample. Due to the separation of these two FOVs in the spatial-frequency domain, they can be fully reconstructed separately, while obtaining two complex wavefronts from the sample at once. Since the optically multiplexed off-axis interferogram is recorded by the camera in a single exposure, fast dynamics can be recorded with a doubled imaging area. We used this technique for quantitative phase microscopy of biological samples with extended FOV. We demonstrate attaching the proposed module to a diffractive phase microscopy interferometer, illuminated by a broadband light source. The biological samples used for the experimental demonstrations include microscopic diatom shells, cancer cells, and flowing blood cells.

PREVAIL: IBM's e-beam technology for next generation lithography

NASA Astrophysics Data System (ADS)

Pfeiffer, Hans C.

2000-07-01

PREVAIL - Projection Reduction Exposure with Variable Axis Immersion Lenses represents the high throughput e-beam projection approach to NGL which IBM is pursuing in cooperation with Nikon Corporation as alliance partner. This paper discusses the challenges and accomplishments of the PREVAIL project. The supreme challenge facing all e-beam lithography approaches has been and still is throughput. Since the throughput of e-beam projection systems is severely limited by the available optical field size, the key to success is the ability to overcome this limitation. The PREVAIL technique overcomes field-limiting off-axis aberrations through the use of variable axis lenses, which electronically shift the optical axis simultaneously with the deflected beam so that the beam effectively remains on axis. The resist images obtained with the Proof-of-Concept (POC) system demonstrate that PREVAIL effectively eliminates off- axis aberrations affecting both resolution and placement accuracy of pixels. As part of the POC system a high emittance gun has been developed to provide uniform illumination of the patterned subfield and to fill the large numerical aperture projection optics designed to significantly reduce beam blur caused by Coulomb interaction.

Acquisition and replay systems for direct-to-digital holography and holovision

DOEpatents

Thomas, Clarence E.; Hanson, Gregory R.

2003-02-25

Improvements to the acquisition and replay systems for direct-to-digital holography and holovision are described. A method of recording an off-axis hologram includes: splitting a laser beam into an object beam and a reference beam; reflecting the reference beam from a reference beam mirror; reflecting the object beam from an illumination beamsplitter; passing the object beam through an objective lens; reflecting the object beam from an object; focusing the reference beam and the object beam at a focal plane of a digital recorder to form an off-axis hologram; digitally recording the off-axis hologram; and transforming the off-axis hologram in accordance with a Fourier transform to obtain a set of results. A method of writing an off-axis hologram includes: passing a laser beam through a spatial light modulator; and focusing the laser beam at a focal plane of a photorefractive crystal to impose a holographic diffraction grating pattern on the photorefractive crystal. A method of replaying an off-axis hologram includes: illuminating a photorefractive crystal having a holographic diffraction grating with a replay beam.

Implantable biaxial piezoresistive accelerometer for sensorimotor control.

PubMed

Zou, Qiang; Tan, Wei; Sok Kim, Eun; Singh, Jasspreet; Loeb, Gerald E

2004-01-01

This paper describes the design, fabrication and test results of a novel biaxial piezoresistive accelerometer and its incorporation into a miniature neuromuscular stimulator called a BION. Because of its highly symmetric twin mass structure, the X and Z axis acceleration can be measured at the same time and the cross axis sensitivity can be minimized by proper piezoresistor design. The X and Z axis sensitivities of the biaxial accelerometer are 0.10 mV/g/V and 1.40 mV/g/V, respectively, which are further increased to 0.65 mV/g/V and 2.40 mV/g/V, respectively, with extra silicon mass added to the proof mass. The cross-axis sensitivity is less than 3.3% among X, Y and Z-axis. An orientation tracking method for human segments by measuring every joint angle is also discussed in this paper. Joint angles can be obtained by processing the outputs of a pair of biaxial accelerometers (placed very close to the joint axis on the adjacent limb links), without having to integrate acceleration or velocity signals, thereby avoiding errors due to offsets and drift.

Association between Mastication, the Hippocampus, and the HPA Axis: A Comprehensive Review.

PubMed

Azuma, Kagaku; Zhou, Qian; Niwa, Masami; Kubo, Kin-Ya

2017-08-03

Mastication is mainly involved in food intake and nutrient digestion with the aid of teeth. Mastication is also important for preserving and promoting general health, including hippocampus-dependent cognition. Both animal and human studies indicate that mastication influences hippocampal functions through the end product of the hypothalamic-pituitary-adrenal (HPA) axis, glucocorticoid (GC). Epidemiologic studies suggest that masticatory dysfunction in aged individuals, such as that resulting from tooth loss and periodontitis, acting as a source of chronic stress, activates the HPA axis, leading to increases in circulating GCs and eventually inducing various physical and psychological diseases, such as cognitive impairment, cardiovascular disorders, and osteoporosis. Recent studies demonstrated that masticatory stimulation or chewing during stressful conditions suppresses the hyperactivity of the HPA axis via GCs and GC receptors within the hippocampus, and ameliorates chronic stress-induced hippocampus-dependent cognitive deficits. Here, we provide a comprehensive overview of current research regarding the association between mastication, the hippocampus, and HPA axis activity. We also discuss several potential molecular mechanisms involved in the interactions between mastication, hippocampal function, and HPA axis activity.

Association between Mastication, the Hippocampus, and the HPA Axis: A Comprehensive Review

PubMed Central

Azuma, Kagaku; Zhou, Qian; Niwa, Masami; Kubo, Kin-ya

2017-01-01

Mastication is mainly involved in food intake and nutrient digestion with the aid of teeth. Mastication is also important for preserving and promoting general health, including hippocampus-dependent cognition. Both animal and human studies indicate that mastication influences hippocampal functions through the end product of the hypothalamic-pituitary-adrenal (HPA) axis, glucocorticoid (GC). Epidemiologic studies suggest that masticatory dysfunction in aged individuals, such as that resulting from tooth loss and periodontitis, acting as a source of chronic stress, activates the HPA axis, leading to increases in circulating GCs and eventually inducing various physical and psychological diseases, such as cognitive impairment, cardiovascular disorders, and osteoporosis. Recent studies demonstrated that masticatory stimulation or chewing during stressful conditions suppresses the hyperactivity of the HPA axis via GCs and GC receptors within the hippocampus, and ameliorates chronic stress-induced hippocampus-dependent cognitive deficits. Here, we provide a comprehensive overview of current research regarding the association between mastication, the hippocampus, and HPA axis activity. We also discuss several potential molecular mechanisms involved in the interactions between mastication, hippocampal function, and HPA axis activity. PMID:28771175

Double diameter boring tool

DOEpatents

Ashbaugh, Fred N.; Murry, Kenneth R.

1988-12-27

A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

Double diameter boring tool

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

Ashbaugh, F.A.; Murry, K.R.

A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting flutes formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first flute tip to the axis of rotation plus the distance from the second flute tip to themore » axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second flute tip to the axis of rotation minus one-half the distance from the first flute tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.« less

Why the long face? The importance of vertical image structure for biological "barcodes" underlying face recognition.

PubMed

Spence, Morgan L; Storrs, Katherine R; Arnold, Derek H

2014-07-29

Humans are experts at face recognition. The mechanisms underlying this complex capacity are not fully understood. Recently, it has been proposed that face recognition is supported by a coarse-scale analysis of visual information contained in horizontal bands of contrast distributed along the vertical image axis-a biological facial "barcode" (Dakin & Watt, 2009). A critical prediction of the facial barcode hypothesis is that the distribution of image contrast along the vertical axis will be more important for face recognition than image distributions along the horizontal axis. Using a novel paradigm involving dynamic image distortions, a series of experiments are presented examining famous face recognition impairments from selectively disrupting image distributions along the vertical or horizontal image axes. Results show that disrupting the image distribution along the vertical image axis is more disruptive for recognition than matched distortions along the horizontal axis. Consistent with the facial barcode hypothesis, these results suggest that human face recognition relies disproportionately on appropriately scaled distributions of image contrast along the vertical image axis. © 2014 ARVO.

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.

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

Power-Factor Calculation under Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation

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

Lee, Seong T; Burress, Timothy A; Hsu, John S

2009-01-01

This paper introduces a new method for calculating the power factor with consideration of the cross saturation between the direct-axis (d-axis) and the quadrature-axis (q-axis) of an interior permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include the cross-saturation effect by adding the cross-coupled inductance terms. This paper also contains the new method of calculating the cross-coupled inductance values as well as self-inductance values in d- and q-axes. The analyzed motor is a high-speed brushless field excitation machine that offers high torque per ampere per core length at low speed and weakened flux at highmore » speed, which was developed for the traction motor of a hybrid electric vehicle.« less

Permanent-magnet switched-flux machine

DOEpatents

Trzynadlowski, Andrzej M.; Qin, Ling

2010-01-12

A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

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).

Exploring tectonomagmatic controls on mid-ocean ridge faulting and morphology with 3-D numerical models

NASA Astrophysics Data System (ADS)

Howell, S. M.; Ito, G.; Behn, M. D.; Olive, J. A. L.; Kaus, B.; Popov, A.; Mittelstaedt, E. L.; Morrow, T. A.

2016-12-01

Previous two-dimensional (2-D) modeling studies of abyssal-hill scale fault generation and evolution at mid-ocean ridges have predicted that M, the ratio of magmatic to total extension, strongly influences the total slip, spacing, and rotation of large faults, as well as the morphology of the ridge axis. Scaling relations derived from these 2-D models broadly explain the globally observed decrease in abyssal hill spacing with increasing ridge spreading rate, as well as the formation of large-offset faults close to the ends of slow-spreading ridge segments. However, these scaling relations do not explain some higher resolution observations of segment-scale variability in fault spacing along the Chile Ridge and the Mid-Atlantic Ridge, where fault spacing shows no obvious correlation with M. This discrepancy between observations and 2-D model predictions illuminates the need for three-dimensional (3-D) numerical models that incorporate the effects of along-axis variations in lithospheric structure and magmatic accretion. To this end, we use the geodynamic modeling software LaMEM to simulate 3-D tectono-magmatic interactions in a visco-elasto-plastic lithosphere under extension. We model a single ridge segment subjected to an along-axis gradient in the rate of magma injection, which is simulated by imposing a mass source in a plane of model finite volumes beneath the ridge axis. Outputs of interest include characteristic fault offset, spacing, and along-axis gradients in seafloor morphology. We also examine the effects of along-axis variations in lithospheric thickness and off-axis thickening rate. The main objectives of this study are to quantify the relative importance of the amount of magmatic extension and the local lithospheric structure at a given along-axis location, versus the importance of along-axis communication of lithospheric stresses on the 3-D fault evolution and morphology of intermediate-spreading-rate ridges.

Water Landing Characteristics of a Reentry Capsule

NASA Technical Reports Server (NTRS)

1958-01-01

Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions.

Water-Landing Characteristics of a Reentry Capsule

NASA Technical Reports Server (NTRS)

McGehee, John R.; Hathaway, Melvin E.; Vaughan, Victor L., Jr.

1959-01-01

Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions.

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.

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 a major advance toward understanding how these tissue layers interact during axis extension with important implications in human disease. PMID:27144312

ACTH and Cortisol Response to Dex/CRH Testing in Women with and without Premenstrual Dysphoria during GnRH Agonist-Induced Hypogonadism and Ovarian Steroid Replacement

PubMed Central

Lee, Ellen E.; Nieman, Lynnette K.; Martinez, Pedro E.; Harsh, Veronica L.; Rubinow, David R.

2012-01-01

Context: During conditions of ovarian suppression, women with premenstrual dysphoria (PMD) experience abnormal behavioral responses to physiological levels of ovarian steroids. Although hypothalamic-pituitary-adrenal (HPA) axis dysregulation frequently accompanies depression, and ovarian steroids regulate HPA axis responsivity, the role of HPA axis dysregulation in PMD is not known. We hypothesized that women with PMD would show abnormalities of HPA axis function analogous to those reported in depressive illness, and that ovarian steroids would differentially regulate HPA axis function in women with PMD compared with asymptomatic controls (AC). Objective: Our objective was to characterize the HPA axis response to physiological levels of estradiol and progesterone in women with PMD and AC. Design and Setting: We conducted an open-label trial of the GnRH agonist depot Lupron with ovarian steroid replacement administered in a double-blind crossover design in an outpatient clinic. Participants: Forty-three women (18 with prospectively confirmed PMD and 25 AC) participated. Interventions: Women received Lupron for 6 months. After 3 months of hypogonadism, women received 5 wk each of estradiol (100-μg patch daily) or progesterone (suppositories 200 mg twice daily). During each condition, combined dexamethasone-suppression/CRH-stimulation tests and 24-h urinary free cortisol levels were performed. Main Outcome Measures: Plasma cortisol and ACTH levels were evaluated. Results: HPA axis function was similar in PMD compared with AC. In all, progesterone significantly increased the secretion of cortisol compared with estradiol [area under the curve (t74 = 3.1; P < 0.01)] and urinary free cortisol (t74 = 3.2; P < 0.01) and ACTH compared with hypogonadism [area under the curve (t74 = 2.4; P < 0.05)]. Conclusions: HPA axis regulation is normal in PMD, suggesting that the pathophysiology of PMD differs from major depression. As observed previously, progesterone but not estradiol up-regulates HPA axis function in women. PMID:22466349

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 movements.

Predictive role of P-wave axis abnormalities in secondary cardiovascular prevention.

PubMed

Lazzeroni, Davide; Bini, Matteo; Camaiora, Umberto; Castiglioni, Paolo; Moderato, Luca; Ugolotti, Pietro Tito; Brambilla, Lorenzo; Brambilla, Valerio; Coruzzi, Paolo

2017-12-01

Background Abnormal P-wave axis has been correlated with an increased risk of all-cause and cardiovascular mortality in a general population. We aimed to evaluate the prognostic role of abnormal P-wave axis in patients undergoing myocardial revascularisation or cardiac valve surgery. Methods We considered data of 810 patients with available P-wave axis measure from a prospective monocentric registry of patients undergoing cardiovascular rehabilitation. A total of 436 patients (54%) underwent myocardial revascularisation, 253 (31%) valve surgery, 71 (9%) combined valve and coronary artery bypass graft surgery and 50 (6%) cardiac surgery for other cardiovascular disease. Mean follow-up was 47 ± 27 months. Results Over the whole group, P-wave axis was 43.8° ± 27.5° and an abnormal P-wave axis was found in 94 patients (12%). The risk of overall (hazard ratio (HR) 2.5, 95% confidence interval (CI) 1.6-4.0, P < 0.001) and cardiovascular mortality (HR 2.9, 95% CI 1.5-5.8, P = 0.002) was significantly higher in patients with abnormal P-wave axis even after adjustment for age, other electrocardiographic variables (PR, QRS, QTc intervals), left ventricular ejection fraction and left atrial volume index. After dividing the population according to the type of disease, patients with abnormal P-wave axis and ischaemic heart disease had 3.9-fold higher risk of cardiovascular mortality (HR 3.9, 95% CI 1.3-12.1, P = 0.017), while a 2.2-fold higher risk of cardiovascular mortality (HR 3.6, 95% CI 1.3-10.1, P = 0.015) was found in those with cardiac valve disease. Conclusion An abnormal P-wave axis represents an independent predictor of both overall and cardiovascular mortality in patients undergoing myocardial revascularisation or cardiac valve surgery.

From lizard body form to serpentiform morphology: The atlas-axis complex in African cordyliformes and their relatives.

PubMed

Čerňanský, Andrej

2016-04-01

The comparative vertebral morphology of the atlas-axis complex in cordyliforms, xantusiid and several skinks is studied here. These lizards are particularly interesting because of their different ecological adaptations and anti-predation strategies, where conformation ranges from the lizard-like body to a snake-like body. This transition to serpentiform morphology shows several evolutionary patterns in the atlas-axis complex: 1) the zygapophyseal articulations are lost in the early stage of the transition. In contrast to mammals, the atlas is more or less locked to the axis in lepidosaurs, but the absence of zygapophyseal articulation releases this locking for rotation. However despite its serpentiform morphology, Chamaesaura is different, in possessing this articulation; 2) the first intercentrum of Chamaesaura and Tetradactylus africanus (serpentiform grass-swimmers) is fully curved anteriorly, underlying the occipital condyle. While this limits ventral skull rotation beyond a certain angle, it locks the skull, which is a crucial adaptation for a sit-and-wait position in grassland habitats that needs to keep the head stabilized; and 3) in Acontias, most of the atlas articular surface with the occipital condyle is formed by the lateral aspect of the articulation area relative to the area located in the dorsal region of the slightly reduced intercentrum. A similar state occurs in amphisbaenians, most likely reflecting a fossorial lifestyle of the limbless lizards. Although Chamaesaura and Tetradactylus live sympatrically in grasslands, Chamaesaura differs in several ways in atlas-axis complex: for example, aforementioned presence of the atlas-axis zygapophyseal articulation, and long posterodorsal processes. Its occipital condyle protrudes further posteriorly, placing the atlas-axis complex further from the endocranium than in Tetradactylus. Hence, adaptation in the same niche, even among sister clades, can lead to different atlas-axis morphology due to different lifestyle strategies, for example, different foraging mode, while similar atlas-axis morphology can evolve in two lineages occupying different niches, as in Ablepharus and Scelotes. © 2016 Wiley Periodicals, Inc.

Hypothalamic-pituitary-adrenal axis response to acute psychosocial stress: Effects of biological sex and circulating sex hormones

PubMed Central

Stephens, Mary Ann C.; Mahon, Pamela B.; McCaul, Mary E.; Wand, Gary S.

2016-01-01

Summary Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis influences the risk for developing stress-related disorders. Sex-dependent differences in the HPA axis stress response are believed to contribute to the different prevalence rates of stress-related disorders found in men and women. However, studies examining the HPA axis stress response have shown mixed support for sex differences, and the role of endogenous sex hormones on HPA axis response has not been adequately examined in humans. This study utilized the largest sample size to date to analyze the effects of biological sex and sex hormones on HPA axis social stress responses. Healthy, 18- to 30- year-old community volunteers (N=282) completed the Trier Social Stress Test (TSST), a widely used and well-validated stress-induction laboratory procedure. All women (n=135) were tested during the follicular phase of their menstrual cycle (when progesterone levels are most similar to men). Adrenocorticotropic hormone (ACTH) and cortisol measures were collected at multiple points throughout pre- and post-TSST. Testosterone and progesterone (in men) and progesterone and estradiol (in women) were determined pre-TSST. Following the TSST, men had greater ACTH and cortisol levels than women. Men had steeper baseline-to-peak and peak-to-end ACTH and cortisol response slopes than women; there was a trend for more cortisol responders among men than women. Testosterone negatively correlated with salivary cortisol response in men, while progesterone negatively correlated with ACTH and cortisol responses in women. These data confirm that men show more robust activation of the HPA axis response to the TSST than do women in the follicular phase of the menstrual cycle. Testosterone results suggest an inhibitory effect on HPA axis reactivity in men. Progesterone results suggest an inhibitory effect on HPA axis reactivity in women. Future work is needed to explain why men mount a greater ACTH and cortisol response to the TSST than do women during the follicular phase of the menstrual cycle. PMID:26773400

Vestibulo-ocular reflex of the squirrel monkey during eccentric rotation with centripetal acceleration along the naso-occipital axis

NASA Technical Reports Server (NTRS)

Merfeld, D. M.; Paloski, W. H. (Principal Investigator)

1996-01-01

The vestibulo-ocular reflexes (VOR) are determined not only by angular acceleration, but also by the presence of gravity and linear acceleration. This phenomenon was studied by measuring three-dimensional nystagmic eye movements, with implanted search coils, in four male squirrel monkeys. Monkeys were rotated in the dark at 200 degrees/s, centrally or 79 cm off-axis, with the axis of rotation always aligned with gravity and the spinal axis of the upright monkeys. The monkey's position relative to the centripetal acceleration (facing center or back to center) had a dramatic influence on the VOR. These studies show that a torsional response was always elicited that acted to shift the axis of eye rotation toward alignment with gravito-inertial force. On the other hand, a slow phase downward vertical response usually existed, which shifted the axis of eye rotation away from the gravito-inertial force. These findings were consistent across all monkeys. In another set of tests, the same monkeys were rapidly tilted about their interaural (pitch) axis. Tilt orientations of 45 degrees and 90 degrees were maintained for 1 min. Other than a compensatory angular VOR during the rotation, no consistent eye velocity response was ever observed during or following the tilt. The absence of any response following tilt proves that the observed torsional and vertical responses were not a positional nystagmus. Model simulations qualitatively predict all components of these eccentric rotation and tilt responses. These simulations support the conclusion that the VOR during eccentric rotation may consist of two components: a linear VOR and a rotational VOR. The model predicts a slow phase downward, vertical, linear VOR during eccentric rotation even though there was never a change in the force aligned with monkey's spinal (Z) axis. The model also predicts the torsional components of the response that shift the rotation axis of the angular VOR toward alignment with gravito-inertial force.

Vestibulo-ocular reflex of the squirrel monkey during eccentric rotation with centripetal acceleration along the naso-occipital axis.

PubMed

Merfeld, D M

1996-01-01

The vestibulo-ocular reflexes (VOR) are determined not only by angular acceleration, but also by the presence of gravity and linear acceleration. This phenomenon was studied by measuring three-dimensional nystagmic eye movements, with implanted search coils, in four male squirrel monkeys. Monkeys were rotated in the dark at 200 degrees/s, centrally or 79 cm off-axis, with the axis of rotation always aligned with gravity and the spinal axis of the upright monkeys. The monkey's position relative to the centripetal acceleration (facing center or back to center) had a dramatic influence on the VOR. These studies show that a torsional response was always elicited that acted to shift the axis of eye rotation toward alignment with gravito-inertial force. On the other hand, a slow phase downward vertical response usually existed, which shifted the axis of eye rotation away from the gravito-inertial force. These findings were consistent across all monkeys. In another set of tests, the same monkeys were rapidly tilted about their interaural (pitch) axis. Tilt orientations of 45 degrees and 90 degrees were maintained for 1 min. Other than a compensatory angular VOR during the rotation, no consistent eye velocity response was ever observed during or following the tilt. The absence of any response following tilt proves that the observed torsional and vertical responses were not a positional nystagmus. Model simulations qualitatively predict all components of these eccentric rotation and tilt responses. These simulations support the conclusion that the VOR during eccentric rotation may consist of two components: a linear VOR and a rotational VOR. The model predicts a slow phase downward, vertical, linear VOR during eccentric rotation even though there was never a change in the force aligned with monkey's spinal (Z) axis. The model also predicts the torsional components of the response that shift the rotation axis of the angular VOR toward alignment with gravito-inertial force.

Predominant typologies of psychopathology in the United States: a latent class analysis.

PubMed

El-Gabalawy, Renée; Tsai, Jack; Harpaz-Rotem, Ilan; Hoff, Rani; Sareen, Jitender; Pietrzak, Robert H

2013-11-01

Latent class analysis (LCA) offers a parsimonious way of classifying common typologies of psychiatric comorbidity. We used LCA to identify the nature and correlates of predominant typologies of Axis I and II disorders in a large and comprehensive population-based sample of U.S. adults. We analyzed data from Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (2004-2005; n = 34,653), a population-based sample of U.S. adults. We derived latent classes based on all assessed Axis I and II disorders and examined the relationship between the identified Axis I classes and lifetime psychiatric disorders and suicide attempts, and physical and mental health-related quality of life. A four-class solution was optimal in characterizing predominant typologies of both Axis I and II disorders. For Axis I disorders, these included low psychopathology (n = 28,935, 84.0%), internalizing (n = 3693, 9.9%), externalizing (n = 1426, 4.5%), and high psychopathology (n = 599, 1.6%) classes. For Axis II disorders, these included no/low personality disorders (n = 31,265, 90.9%), obsessive/paranoid (n = 1635, 4.6%), borderline/dysregulated (n = 1319, 3.4%), and highly comorbid (n = 434, 1.1%) classes. Compared to the low psychopathology class, all other Axis I classes had significantly increased odds of mental disorders, elevated Axis II classes, suicide attempts and poorer quality of life, with the high psychopathology class having the overall highest rates of these correlates, with the exception of substance use disorders. Compared to the low psychopathology class, the internalizing and externalizing classes had increased rates of mood and anxiety disorders, and substance use disorders, respectively. Axis I and II psychopathology among U.S. adults may be best represented by four predominant typologies. Characterizing co-occurring patterns of psychopathology using person-based typologies represents a higher-order classification system that may be useful in clinical and research settings. Published by Elsevier Ltd.

Growth of Highly c-axis Oriented and/or Epitaxial Single-Domain b-axis Oriented La5Ca9Cu24O41 Thin Films by Pulsed Laser Deposition

DTIC Science & Technology

2016-04-01

project attempted to grow La5Ca9Cu24O41 (LCCO) films on important substrates with the high- thermal -conductivity direction parallel or perpendicular...to the surface of the substrate, counting success as demonstration of b-axis or c-axis oriented LCCO films along with measurement of bulk thermal ...deposition, LCCO, La5Ca9Cu24O41, thermal conductivity, epitaxy 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT SAR 18. NUMBER OF PAGES 24

The reliability of axis V of the multiaxial classification scheme.

PubMed

van Goor-Lambo, G

1987-07-01

In a reliability study concerning axis V (abnormal psychosocial situations) of the Multiaxial classification scheme for psychiatric disorders in childhood and adolescence, it was found that the level of agreement in scoring was adequate for only 2 out of 12 categories. A proposal for a modification of axis V was made, including a differentiation and regrouping of the categories and an adjustment of the descriptions in the glossary. With this modification of axis V another reliability study was carried out, in which the level of agreement in scoring was adequate for 12 out of 16 categories.

Gimbaled multispectral imaging system and method

DOEpatents

Brown, Kevin H.; Crollett, Seferino; Henson, Tammy D.; Napier, Matthew; Stromberg, Peter G.

2016-01-26

A gimbaled multispectral imaging system and method is described herein. In an general embodiment, the gimbaled multispectral imaging system has a cross support that defines a first gimbal axis and a second gimbal axis, wherein the cross support is rotatable about the first gimbal axis. The gimbaled multispectral imaging system comprises a telescope that fixed to an upper end of the cross support, such that rotation of the cross support about the first gimbal axis causes the tilt of the telescope to alter. The gimbaled multispectral imaging system includes optics that facilitate on-gimbal detection of visible light and off-gimbal detection of infrared light.

Fuel cell stack with passive air supply

DOEpatents

Ren, Xiaoming; Gottesfeld, Shimshon

2006-01-17

A fuel cell stack has a plurality of polymer electrolyte fuel cells (PEFCs) where each PEFC includes a rectangular membrane electrode assembly (MEA) having a fuel flow field along a first axis and an air flow field along a second axis perpendicular to the first axis, where the fuel flow field is long relative to the air flow field. A cathode air flow field in each PEFC has air flow channels for air flow parallel to the second axis and that directly open to atmospheric air for air diffusion within the channels into contact with the MEA.

Systems and methods for displaying data in split dimension levels

DOEpatents

Stolte, Chris; Hanrahan, Patrick

2015-07-28

Systems and methods for displaying data in split dimension levels are disclosed. In some implementations, a method includes: at a computer, obtaining a dimensional hierarchy associated with a dataset, wherein the dimensional hierarchy includes at least one dimension and a sub-dimension of the at least one dimension; and populating information representing data included in the dataset into a visual table having a first axis and a second axis, wherein the first axis corresponds to the at least one dimension and the second axis corresponds to the sub-dimension of the at least one dimension.

Alignment of x-ray tube focal spots for spectral measurement.

PubMed

Nishizawa, K; Maekoshi, H; Kamiya, Y; Kobayashi, Y; Ohara, K; Sakuma, S

1982-01-01

A general method to align a diagnostic x-ray machine for x-ray spectrum measurement purpose was theoretically and experimentally investigated by means of the optical alignment of focal pinhole images. Focal pinhole images were obtained by using a multi-pinholed lead plate. the vertical plane, including the central axis and tube axis, was decided upon by observing the symmetry of focal images. the central axis was designated as a line through the center of focus parallel to the target surface lying in the vertical plane. A method to determine the manipulation of the central axis in any direction is presented.

HPA and SAM axis responses as correlates of self- vs parental ratings of anxiety in boys with an Autistic Disorder.

PubMed

Bitsika, Vicki; Sharpley, Christopher F; Sweeney, John A; McFarlane, James R

2014-03-29

Anxiety and Autistic Disorder (AD) are both neurological conditions and both disorders share some features that make it difficult to precisely allocate specific symptoms to each disorder. HPA and SAM axis activities have been conclusively associated with anxiety, and may provide a method of validating anxiety rating scale assessments given by parents and their children with AD about those children. Data from HPA axis (salivary cortisol) and SAM axis (salivary alpha amylase) responses were collected from a sample of 32 high-functioning boys (M age=11yr) with an Autistic Disorder (AD) and were compared with the boys' and their mothers' ratings of the boys' anxiety. There was a significant difference between the self-ratings given by the boys and ratings given about them by their mothers. Further, only the boys' self-ratings of their anxiety significantly predicted the HPA axis responses and neither were significantly related to SAM axis responses. Some boys showed cortisol responses which were similar to that previously reported in children who had suffered chronic and severe anxiety arising from stressful social interactions. As well as suggesting that some boys with an AD can provide valid self-assessments of their anxiety, these data also point to the presence of very high levels of chronic HPA-axis arousal and consequent chronic anxiety in these boys. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Along-axis hydrothermal flow at the axis of slow spreading Mid-Ocean Ridges: Insights from numerical models of the Lucky Strike vent field (MAR)

NASA Astrophysics Data System (ADS)

Fontaine, Fabrice J.; Cannat, Mathilde; Escartin, Javier; Crawford, Wayne C.

2014-07-01

processes and efficiency of hydrothermal heat extraction along the axis of mid-ocean ridges are controlled by lithospheric thermal and permeability structures. Hydrothermal circulation models based on the structure of fast and intermediate spreading ridges predict that hydrothermal cell organization and vent site distribution are primarily controlled by the thermodynamics of high-temperature mid-ocean ridge hydrothermal fluids. Using recent constraints on shallow structure at the slow spreading Lucky Strike segment along the Mid-Atlantic Ridge, we present a physical model of hydrothermal cooling that incorporates the specificities of a magma-rich slow spreading environment. Using three-dimensional numerical models, we show that, in contrast to the aforementioned models, the subsurface flow at Lucky Strike is primarily controlled by across-axis permeability variations. Models with across-axis permeability gradients produce along-axis oriented hydrothermal cells and an alternating pattern of heat extraction highs and lows that match the distribution of microseismic clusters recorded at the Lucky Strike axial volcano. The flow is also influenced by temperature gradients at the base of the permeable hydrothermal domain. Although our models are based on the structure and seismicity of the Lucky Strike segment, across-axis permeability gradients are also likely to occur at faster spreading ridges and these results may also have important implications for the cooling of young crust at fast and intermediate spreading centers.

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.

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

Nodal signalling determines biradial asymmetry in Hydra.

PubMed

Watanabe, Hiroshi; Schmidt, Heiko A; Kuhn, Anne; Höger, Stefanie K; Kocagöz, Yigit; Laumann-Lipp, Nico; Ozbek, Suat; Holstein, Thomas W

2014-11-06

In bilaterians, three orthogonal body axes define the animal form, with distinct anterior-posterior, dorsal-ventral and left-right asymmetries. The key signalling factors are Wnt family proteins for the anterior-posterior axis, Bmp family proteins for the dorsal-ventral axis and Nodal for the left-right axis. Cnidarians, the sister group to bilaterians, are characterized by one oral-aboral body axis, which exhibits a distinct biradiality of unknown molecular nature. Here we analysed the biradial growth pattern in the radially symmetrical cnidarian polyp Hydra, and we report evidence of Nodal in a pre-bilaterian clade. We identified a Nodal-related gene (Ndr) in Hydra magnipapillata, and this gene is essential for setting up an axial asymmetry along the main body axis. This asymmetry defines a lateral signalling centre, inducing a new body axis of a budding polyp orthogonal to the mother polyp's axis. Ndr is expressed exclusively in the lateral bud anlage and induces Pitx, which encodes an evolutionarily conserved transcription factor that functions downstream of Nodal. Reminiscent of its function in vertebrates, Nodal acts downstream of β-Catenin signalling. Our data support an evolutionary scenario in which a 'core-signalling cassette' consisting of β-Catenin, Nodal and Pitx pre-dated the cnidarian-bilaterian split. We presume that this cassette was co-opted for various modes of axial patterning: for example, for lateral branching in cnidarians and left-right patterning in bilaterians.

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.

Clinical correlates of hypothalamic-pituitary-adrenal axis measures in individuals at risk for psychosis and with first-episode psychosis.

PubMed

Labad, Javier; Armario, Antonio; Nadal, Roser; Solé, Montse; Gutiérrez-Zotes, Alfonso; Montalvo, Itziar; Moreno-Samaniego, Lorena; Martorell, Lourdes; Sánchez-Gistau, Vanessa; Vilella, Elisabet

2018-07-01

Hypothalamic-pituitary-adrenal (HPA) axis alterations in at-risk mental states (ARMS) resemble those observed in established psychosis but are less consistent. We aimed to explore HPA axis abnormalities in both first-episode psychosis (FEP) and ARMS patients, while controlling for psychopathological symptoms. We studied 21 ARMS, 34 FEP patients and 34 healthy subjects. Clinical assessment included psychopathological symptoms (positive, negative, disorganized, excited and depressive symptoms) and stress measures. Saliva cortisol levels were determined at awakening, 30' and 60' post-awakening, 10:00 h, 23:00 h and 10:00 h on the day after the administration of 0.25 mg of dexamethasone, which occurred at 23:00 h. Three HPA axis measures were calculated: cortisol awakening response (CAR), cortisol diurnal slope and cortisol suppression ratio of the dexamethasone suppression test (DST). There were no significant differences between groups in HPA axis measures. However, when exploring the relationship between HPA axis measures and psychopathological symptoms, in ARMS subjects (but not FEP patients), a flatter cortisol slope was associated with more prominent negative symptoms, whereas a blunted CAR was associated with excited symptoms. Although no significant differences in HPA axis measures were found between diagnostic groups, subtle abnormalities in the CAR or circadian cortisol rhythmicity might be important for the phenotype of ARMS individuals. Copyright © 2018. Published by Elsevier B.V.

Off-axis Gamma-ray Burst Afterglow Modeling Based on a Two-dimensional Axisymmetric Hydrodynamics Simulation

NASA Astrophysics Data System (ADS)

van Eerten, Hendrik; Zhang, Weiqun; MacFadyen, Andrew

2010-10-01

Starting as highly relativistic collimated jets, gamma-ray burst outflows gradually slow down and become nonrelativistic spherical blast waves. Although detailed analytical solutions describing the afterglow emission received by an on-axis observer during both the early and late phases of the outflow evolution exist, a calculation of the received flux during the intermediate phase and for an off-axis observer requires either a more simplified analytical model or direct numerical simulations of the outflow dynamics. In this paper, we present light curves for off-axis observers covering the long-term evolution of the blast wave, calculated from a high-resolution two-dimensional relativistic hydrodynamics simulation using a synchrotron radiation model. We compare our results to earlier analytical work and calculate the consequence of the observer angle with respect to the jet axis both for the detection of orphan afterglows and for jet break fits to the observational data. We confirm earlier results in the literature finding that only a very small number of local type Ibc supernovae can harbor an orphan afterglow. For off-axis observers, the observable jet break can be delayed up to several weeks, potentially leading to overestimation of the beaming-corrected total energy. In addition we find that, when using our off-axis light curves to create synthetic Swift X-ray data, jet breaks are likely to remain hidden in the data.

The potential complications of open carpal tunnel release surgery to the ulnar neurovascular bundle and its branches: A cadaveric study.

PubMed

Boughton, O; Adds, P J; Jayasinghe, J A P

2010-07-01

This study investigated the ulnar artery and the ulnar nerve and its branches in the palm to assess how frequently they may be at risk of damage during open carpal tunnel release surgery. Twenty-one formalin-embalmed cadaveric hands were dissected, and the proximity of the ulnar neurovascular bundle to two different lines of incision, the 3rd and 4th interdigital web space axis and the ring finger axis, was assessed and compared. It was found that an incision in the latter (ring finger) axis put the ulnar artery at risk in 12 of 21 specimens, whereas an incision in the former axis (3rd/4th interdigital web space) put the ulnar artery at risk in only two specimens. In 15 hands at least one structure (the ulnar artery or a branch of the ulnar nerve) was at risk in the ring finger axis compared to only seven hands in the axis of the 3rd/4th interdigital web space. We conclude that the ulnar artery and branches of the ulnar nerve are at increased risk of damage with an incision in the axis of the ring finger. The importance of using a blunt dissection technique under direct vision during surgery to identify and preserve these structures and median nerve branches is emphasized. (c) 2010 Wiley-Liss, Inc.

Evaluation of Hypothalamic-Pituitary-Adrenal Axis Suppression following Cutaneous Use of Topical Corticosteroids in Children: A Meta-Analysis.

PubMed

Wood Heickman, Lauren K; Davallow Ghajar, Ladan; Conaway, Mark; Rogol, Alan D

2018-06-13

A meta-analysis was performed to determine the likelihood of hypothalamic-pituitary-adrenal (HPA) axis suppression following short-term cutaneous treatment of atopic dermatitis with topical corticosteroids (TCS) in pediatric patients. All published pediatric clinical trials evaluating TCS use with pre- and post-treatment HPA axis assessment by cosyntropin stimulation testing were included. Of 128 eligible trials, 12 were selected for meta-analysis with a total of 522 participants. There were 20 observed cases of HPA axis suppression (3.8%, 95% CI 2.4-5.8). The percentage of HPA axis suppression with low- (classes 6-7), medium- (classes 3-5) and high-potency (classes 1-2) TCS use was 2% (3 of 148 patients, 95% CI 0.7-5.8), 3.1% (7 of 223 patients, 95% CI 1.5-6.3), and 6.6% (10 of 151 patients, 95% CI 3.6-11.8), respectively. There is a low rate of reversible HPA axis suppression with the use of mid- to low-potency TCS compared to more potent formulations. In pediatric clinical practice, the limited use of mid- to low-potency TCS is rarely associated with clinically significant adrenal insufficiency or adrenal crisis. In the absence of signs and symptoms of adrenal insufficiency, there is little need to test the HPA axis of these patients. © 2018 S. Karger AG, Basel.

Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: Recommendations of the International RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group†

PubMed Central

Schiffman, Eric; Ohrbach, Richard; Truelove, Edmond; Look, John; Anderson, Gary; Goulet, Jean-Paul; List, Thomas; Svensson, Peter; Gonzalez, Yoly; Lobbezoo, Frank; Michelotti, Ambra; Brooks, Sharon L.; Ceusters, Werner; Drangsholt, Mark; Ettlin, Dominik; Gaul, Charly; Goldberg, Louis J.; Haythornthwaite, Jennifer A.; Hollender, Lars; Jensen, Rigmor; John, Mike T.; De Laat, Antoon; de Leeuw, Reny; Maixner, William; van der Meulen, Marylee; Murray, Greg M.; Nixdorf, Donald R.; Palla, Sandro; Petersson, Arne; Pionchon, Paul; Smith, Barry; Visscher, Corine M.; Zakrzewska, Joanna; Dworkin, Samuel F.

2015-01-01

Aims The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥ 0.95. Consequently, these empirical results supported the development of revised RDC/TMD Axis I diagnostic algorithms that were subsequently demonstrated to be valid for the most common pain-related TMD and for one temporomandibular joint (TMJ) intra-articular disorder. The original RDC/TMD Axis II instruments were shown to be both reliable and valid. Working from these findings and revisions, two international consensus workshops were convened, from which recommendations were obtained for the finalization of new Axis I diagnostic algorithms and new Axis II instruments. Methods Through a series of workshops and symposia, a panel of clinical and basic science pain experts modified the revised RDC/TMD Axis I algorithms by using comprehensive searches of published TMD diagnostic literature followed by review and consensus via a formal structured process. The panel's recommendations for further revision of the Axis I diagnostic algorithms were assessed for validity by using the Validation Project's data set, and for reliability by using newly collected data from the ongoing TMJ Impact Project—the follow-up study to the Validation Project. New Axis II instruments were identified through a comprehensive search of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. Results The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting any pain-related TMD as well as valid diagnostic criteria for differentiating the most common pain-related TMD (sensitivity ≥ 0.86, specificity ≥ 0.98) and for one intra-articular disorder (sensitivity of 0.80 and specificity of 0.97). Diagnostic criteria for other common intra-articular disorders lack adequate validity for clinical diagnoses but can be used for screening purposes. Inter-examiner reliability for the clinical assessment associated with the validated DC/TMD criteria for pain-related TMD is excellent (kappa ≥ 0.85). Finally, a comprehensive classification system that includes both the common and less common TMD is also presented. The Axis II protocol retains selected original RDC/TMD screening instruments augmented with new instruments to assess jaw function as well as behavioral and additional psychosocial factors. The Axis II protocol is divided into screening and comprehensive self-report instrument sets. The screening instruments’ 41 questions assess pain intensity, pain-related disability, psychological distress, jaw functional limitations, and parafunctional behaviors, and a pain drawing is used to assess locations of pain. The comprehensive instruments, composed of 81 questions, assess in further detail jaw functional limitations and psychological distress as well as additional constructs of anxiety and presence of comorbid pain conditions. Conclusion The recommended evidence-based new DC/TMD protocol is appropriate for use in both clinical and research settings. More comprehensive instruments augment short and simple screening instruments for Axis I and Axis II. These validated instruments allow for identification of patients with a range of simple to complex TMD presentations. PMID:24482784

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 of the AXIe structures.

A Small Range Six-Axis Accelerometer Designed with High Sensitivity DCB Elastic Element

PubMed Central

Sun, Zhibo; Liu, Jinhao; Yu, Chunzhan; Zheng, Yili

2016-01-01

This paper describes a small range six-axis accelerometer (the measurement range of the sensor is ±g) with high sensitivity DCB (Double Cantilever Beam) elastic element. This sensor is developed based on a parallel mechanism because of the reliability. The accuracy of sensors is affected by its sensitivity characteristics. To improve the sensitivity, a DCB structure is applied as the elastic element. Through dynamic analysis, the dynamic model of the accelerometer is established using the Lagrange equation, and the mass matrix and stiffness matrix are obtained by a partial derivative calculation and a conservative congruence transformation, respectively. By simplifying the structure of the accelerometer, a model of the free vibration is achieved, and the parameters of the sensor are designed based on the model. Through stiffness analysis of the DCB structure, the deflection curve of the beam is calculated. Compared with the result obtained using a finite element analysis simulation in ANSYS Workbench, the coincidence rate of the maximum deflection is 89.0% along the x-axis, 88.3% along the y-axis and 87.5% along the z-axis. Through strain analysis of the DCB elastic element, the sensitivity of the beam is obtained. According to the experimental result, the accuracy of the theoretical analysis is found to be 90.4% along the x-axis, 74.9% along the y-axis and 78.9% along the z-axis. The measurement errors of linear accelerations ax, ay and az in the experiments are 2.6%, 0.6% and 1.31%, respectively. The experiments prove that accelerometer with DCB elastic element performs great sensitive and precision characteristics. PMID:27657089

attitude control design for the solar polar orbit radio telesope

NASA Astrophysics Data System (ADS)

Gao, D.; Zheng, J.

This paper studies the attitude dynamics and control of the Solar Polar Orbit Radio Telescope SPORT The SPORT which consists of one parent satellite and eight tethered satellites runs around the Sun in a polar orbit The parent satellite locates at the mass center of the constellation and tethered satellites which are tied with the parent satellite through a non-electric rope rotate around the parent satellite It is also supposed that the parent satellite and all tethered satellites are in a plane when the constellation works begin figure htbp centerline includegraphics width 3 85in height 2 38in 75271331 6a6eb71057 doc1 eps label fig1 end figure Fig 1 the SPORT constellation Firstly this paper gives the dynamic equations of the tethered satellite and the parent satellite From the dynamic characteristic of the tethered satellite we then find that the roll axis is coupled with the yaw axis The control torque of the roll axis can control the yaw angle But the control torque of the roll axis and pitch axis provided by the tether is very small it can not meet the accuracy requirement of the yaw angle In order to improve the attitude pointing accuracy of the tethered satellite a gradient pole is set in the negative orientation of the yaw axis The gradient pole can improve not only the attitude accuracy of roll angle and pitch angle but also that of the yaw angle indirectly As to the dynamic characteristic of the parent satellite the roll axis is coupled with the pitch axis due to the spinning angular velocity At the same

Analysis on influence of installation error of off-axis three-mirror optical system on imaging line-of-sight

NASA Astrophysics Data System (ADS)

Gao, Lingyu; Li, Xinghua; Guo, Qianrui; Quan, Jing; Hu, Zhengyue; Su, Zhikun; Zhang, Dong; Liu, Peilu; Li, Haopeng

2018-01-01

The internal structure of off-axis three-mirror system is commonly complex. The mirror installation error in assembly always affects the imaging line-of-sight and further degrades the image quality. Due to the complexity of the optical path in off-axis three-mirror optical system, the straightforward theoretical analysis on the variations of imaging line-of-sight is extremely difficult. In order to simplify the theoretical analysis, an equivalent single-mirror system is proposed and presented in this paper. In addition, the mathematical model of single-mirror system is established and the accurate expressions of imaging coordinate are derived. Utilizing the simulation software ZEMAX, off-axis three-mirror model and single-mirror model are both established. By adjusting the position of mirror and simulating the line-of-sight rotation of optical system, the variations of imaging coordinates are clearly observed. The final simulation results include: in off-axis three-mirror system, the varying sensitivity of the imaging coordinate to the rotation of line-of-sight is approximately 30 um/″; in single-mirror system, the varying sensitivity of the imaging coordinate to the rotation of line-of-sight is 31.5 um/″. Compared to the simulation results of the off-axis three-mirror model, the 5% relative error of single-mirror model analysis highly satisfies the requirement of equivalent analysis and also verifies its validity. This paper presents a new method to analyze the installation error of the mirror in the off-axis three-mirror system influencing on the imaging line-of-sight. Moreover, the off-axis three-mirror model is totally equivalent to the single-mirror model in theoretical analysis.

Effects of high fat diet on the Basal activity of the hypothalamus-pituitary-adrenal axis in mice: a systematic review.

PubMed

Auvinen, H E; Romijn, J A; Biermasz, N R; Havekes, L M; Smit, J W A; Rensen, P C N; Pereira, A M

2011-12-01

Hypothalamus-pituitary-adrenal-axis activity is suggested to be involved in the pathophysiology of the metabolic syndrome. In diet-induced obesity mouse models, features of the metabolic syndrome are induced by feeding high fat diet. However, the models reveal conflicting results with respect to the hypothalamus-pituitary-adrenal-axis activation. The aim of this review was to assess the effects of high fat feeding on the activity of the hypothalamus-pituitary-adrenal-axis in mice. PubMed, EMBASE, Web of Science, the Cochrane database, and Science Direct were electronically searched and reviewed by 2 individual researchers. We included only original mouse studies reporting parameters of the hypothalamus-pituitary-adrenal-axis after high fat feeding, and at least 1 basal corticosterone level with a proper control group. Studies with adrenalectomized mice, transgenic animals only, high fat diet for less than 2 weeks, or other interventions besides high fat diet, were excluded. 20 studies were included. The hypothalamus-pituitary-adrenal-axis evaluation was the primary research question in only 5 studies. Plasma corticosterone levels were unchanged in 40%, elevated in 30%, and decreased in 20% of the studies. The effects in the peripheral tissues and the central nervous system were also inconsistent. However, major differences were found between mouse strains, experimental conditions, and the content and duration of the diets. This systematic review demonstrates that the effects of high fat feeding on the basal activity of the hypothalamus-pituitary-adrenal-axis in mice are limited and inconclusive. Differences in experimental conditions hamper comparisons and accentuate the need for standardized evaluations to discern the effects of diet-induced obesity on the hypothalamus-pituitary-adrenal-axis. © Georg Thieme Verlag KG Stuttgart · New York.

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.

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.

The effects of transducer geometry on artifacts common to diagnostic bone imaging with conventional medical ultrasound.

PubMed

Mauldin, F William; Owen, Kevin; Tiouririne, Mohamed; Hossack, John A

2012-06-01

The portability, low cost, and non-ionizing radiation associated with medical ultrasound suggest that it has potential as a superior alternative to X-ray for bone imaging. However, when conventional ultrasound imaging systems are used for bone imaging, clinical acceptance is frequently limited by artifacts derived from reflections occurring away from the main axis of the acoustic beam. In this paper, the physical source of off-axis artifacts and the effect of transducer geometry on these artifacts are investigated in simulation and experimental studies. In agreement with diffraction theory, the sampled linear-array geometry possessed increased off-axis energy compared with single-element piston geometry, and therefore, exhibited greater levels of artifact signal. Simulation and experimental results demonstrated that the linear-array geometry exhibited increased artifact signal when the center frequency increased, when energy off-axis to the main acoustic beam (i.e., grating lobes) was perpendicularly incident upon off-axis surfaces, and when off-axis surfaces were specular rather than diffusive. The simulation model used to simulate specular reflections was validated experimentally and a correlation coefficient of 0.97 between experimental and simulated peak reflection contrast was observed. In ex vivo experiments, the piston geometry yielded 4 and 6.2 dB average contrast improvement compared with the linear array when imaging the spinous process and interlaminar space of an animal spine, respectively. This work indicates that off-axis reflections are a major source of ultrasound image artifacts, particularly in environments comprising specular reflecting (i.e., bone or bone-like) objects. Transducer geometries with reduced sensitivity to off-axis surface reflections, such as a piston transducer geometry, yield significant reductions in image artifact.

Hypothalamic-pituitary-adrenal axis genetic variation and early stress moderates amygdala function.

PubMed

Di Iorio, Christina R; Carey, Caitlin E; Michalski, Lindsay J; Corral-Frias, Nadia S; Conley, Emily Drabant; Hariri, Ahmad R; Bogdan, Ryan

2017-06-01

Early life stress may precipitate psychopathology, at least in part, by influencing amygdala function. Converging evidence across species suggests that links between childhood stress and amygdala function may be dependent upon hypothalamic-pituitary-adrenal (HPA) axis function. Using data from college-attending non-Hispanic European-Americans (n=308) who completed the Duke Neurogenetics Study, we examined whether early life stress (ELS) and HPA axis genetic variation interact to predict threat-related amygdala function as well as psychopathology symptoms. A biologically-informed multilocus profile score (BIMPS) captured HPA axis genetic variation (FKBP5 rs1360780, CRHR1 rs110402; NR3C2 rs5522/rs4635799) previously associated with its function (higher BIMPS are reflective of higher HPA axis activity). BOLD fMRI data were acquired while participants completed an emotional face matching task. ELS and depression and anxiety symptoms were measured using the childhood trauma questionnaire and the mood and anxiety symptom questionnaire, respectively. The interaction between HPA axis BIMPS and ELS was associated with right amygdala reactivity to threat-related stimuli, after accounting for multiple testing (empirical-p=0.016). Among individuals with higher BIMPS (i.e., the upper 21.4%), ELS was positively coupled with threat-related amygdala reactivity, which was absent among those with average or low BIMPS. Further, higher BIMPS were associated with greater self-reported anxious arousal, though there was no evidence that amygdala function mediated this relationship. Polygenic variation linked to HPA axis function may moderate the effects of early life stress on threat-related amygdala function and confer risk for anxiety symptomatology. However, what, if any, neural mechanisms may mediate the relationship between HPA axis BIMPS and anxiety symptomatology remains unclear. Copyright © 2017 Elsevier Ltd. All rights reserved.

Attitude-Independent Magnetometer Calibration for Spin-Stabilized Spacecraft

NASA Technical Reports Server (NTRS)

Natanson, Gregory

2005-01-01

The paper describes a three-step estimator to calibrate a Three-Axis Magnetometer (TAM) using TAM and slit Sun or star sensor measurements. In the first step, the Calibration Utility forms a loss function from the residuals of the magnitude of the geomagnetic field. This loss function is minimized with respect to biases, scale factors, and nonorthogonality corrections. The second step minimizes residuals of the projection of the geomagnetic field onto the spin axis under the assumption that spacecraft nutation has been suppressed by a nutation damper. Minimization is done with respect to various directions of the body spin axis in the TAM frame. The direction of the spin axis in the inertial coordinate system required for the residual computation is assumed to be unchanged with time. It is either determined independently using other sensors or included in the estimation parameters. In both cases all estimation parameters can be found using simple analytical formulas derived in the paper. The last step is to minimize a third loss function formed by residuals of the dot product between the geomagnetic field and Sun or star vector with respect to the misalignment angle about the body spin axis. The method is illustrated by calibrating TAM for the Fast Auroral Snapshot Explorer (FAST) using in-flight TAM and Sun sensor data. The estimated parameters include magnetic biases, scale factors, and misalignment angles of the spin axis in the TAM frame. Estimation of the misalignment angle about the spin axis was inconclusive since (at least for the selected time interval) the Sun vector was about 15 degrees from the direction of the spin axis; as a result residuals of the dot product between the geomagnetic field and Sun vectors were to a large extent minimized as a by-product of the second step.

Patterning of anteroposterior body axis displayed in the expression of Hox genes in sea cucumber Apostichopus japonicus.

PubMed

Kikuchi, Mani; Omori, Akihito; Kurokawa, Daisuke; Akasaka, Koji

2015-09-01

The presence of an anteroposterior body axis is a fundamental feature of bilateria. Within this group, echinoderms have secondarily evolved pentameral symmetric body plans. Although all echinoderms present bilaterally symmetric larval stages, they dramatically rearrange their body axis and develop a pentaradial body plan during metamorphosis. Therefore, the location of their anteroposterior body axis in adult forms remains a contentious issue. Unlike other echinoderms, sea cucumbers present an obvious anteroposterior axis not rearranged during metamorphosis, thus representing an interesting group to study their anteroposterior axis patterning. Hox genes are known to play a broadly conserved role in anteroposterior axis patterning in deuterostomes. Here, we report the expression patterns of Hox genes from early development to pentactula stage in sea cucumber. In early larval stages, five Hox genes (AjHox1, AjHox7, AjHox8, AjHox11/13a, and AjHox11/13b) were expressed sequentially along the archenteron, suggesting that the role of anteroposterior patterning of the Hox genes is conserved in bilateral larvae of echinoderms. In doliolaria and pentactula stages, eight Hox genes (AjHox1, AjHox5, AjHox7, AjHox8, AjHox9/10, AjHox11/13a, AjHox11/13b, and AjHox11/13c) were expressed sequentially along the digestive tract, following a similar expression pattern to that found in the visceral mesoderm of other bilateria. Unlike other echinoderms, pentameral expression patterns of AjHox genes were not observed in sea cucumber. Altogether, we concluded that AjHox genes are involved in the patterning of the digestive tract in both larvae and metamorphosis of sea cucumbers. In addition, the anteroposterior axis in sea cucumbers might be patterned like that of other bilateria.

Magneto-crystalline anisotropy of NdFe0.9Mn0.1O3 single crystal

NASA Astrophysics Data System (ADS)

Mihalik, Marián; Mihalik, Matúš; Zentková, Mária; Uhlířová, Klára; Kratochvílová, Marie; Roupcová, Pavla

2018-05-01

Our present study on oriented single crystal revealed huge magneto-crystalline anisotropy with respect to principal crystallographic axes, even several magnetic transitions were observed below TN = 748 K (c-axis) at 700 K (a-axis) as well 657 K (b-axis). The spin reorientation of magnetic moment takes place in very narrow temperature range between 135 K and 125 K and is attributed to vanishing of ferromagnetic component aligned along b-axis. Measurements of magnetic isotherms trace the development of ferromagnetic component and revealed the intermediate temperature range between 120 K and 20 K which is characterised by zero ferromagnetic components in any principal crystal direction. The ferromagnetic component develops consecutive at low temperature below 20 K along a-axis. Our study indicates completely different magnetic structure of NdFe0.9Mn0.1O3 below 135 K in comparison with NdFeO3.

The assessment of personality disorders: implications for cognitive and behavior therapy.

PubMed

Van Velzen, C J; Emmelkamp, P M

1996-08-01

This article reviews the comorbidity of personality disorders (PDs) and Axis I disorders and discusses implications for assessment and treatment. Pros and cons of various assessment methods are discussed. The co-occurrence of PDs with Axis I disorders is considerable; roughly half of patients with anxiety disorders, depressive disorders or eating disorders received a PD diagnosis. Comorbidity models are discussed and implications for assessment and treatment are provided. Regarding the impact of PDs on cognitive-behavioral treatment outcome for Axis I disorders, conflicting results are found due to differences in assessment methods, treatment strategies, and patient samples. It is argued that additional Axis I pathology should be taken into account when studying the impact of PDs on treatment outcome for the target Axis I disorders. Finally, it is argued that the interpersonal behavior of the PD patient and the therapeutic relationship deserve more attention in the assessment and treatment of patients with PDs.

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.

Normalized Point Source Sensitivity for Off-Axis Optical Performance Evaluation of the Thirty Meter Telescope

NASA Technical Reports Server (NTRS)

Seo, Byoung-Joon; Nissly, Carl; Troy, Mitchell; Angeli, George

2010-01-01

The Normalized Point Source Sensitivity (PSSN) has previously been defined and analyzed as an On-Axis seeing-limited telescope performance metric. In this paper, we expand the scope of the PSSN definition to include Off-Axis field of view (FoV) points and apply this generalized metric for performance evaluation of the Thirty Meter Telescope (TMT). We first propose various possible choices for the PSSN definition and select one as our baseline. We show that our baseline metric has useful properties including the multiplicative feature even when considering Off-Axis FoV points, which has proven to be useful for optimizing the telescope error budget. Various TMT optical errors are considered for the performance evaluation including segment alignment and phasing, segment surface figures, temperature, and gravity, whose On-Axis PSSN values have previously been published by our group.

Evolution of low-aspect-ratio rectangular synthetic jets in a quiescent environment

NASA Astrophysics Data System (ADS)

Wang, Lei; Feng, Li-Hao; Wang, Jin-Jun; Li, Tian

2018-06-01

An experimental study was conducted on the evolution of low-aspect-ratio (AR) rectangular synthetic jets using time-resolved two-dimensional particle image velocimetry and stereoscopic particle image velocimetry. Five orifice ARs ranging from 1 to 5 were found to have an obvious effect on the axis switching of vortex rings and the near-field flow physics at a uniform Reynolds number of 166 and non-dimensional stroke length of 4.5. Compared with conventional continuous jets, rectangular synthetic jets displayed more times of axis switching and the first axis-switching location was closer to the jet exit. Two types of different streamwise vortices, SV-I and SV-II, were detected in the near field as the characteristic products of axis switching. Influenced by the axis switching and streamwise vortices, significant entrainment and mixing enhancement was demonstrated for low-AR rectangular synthetic jets.

Dependence of L-mode confinement on the electron cyclotron power deposition profile in the TCV tokamak

NASA Astrophysics Data System (ADS)

Kirneva, N. A.; Razumova, K. A.; Pochelon, A.; Behn, R.; Coda, S.; Curchod, L.; Duval, B. P.; Goodman, T. P.; Labit, B.; Karpushov, A. N.; Rancic, M.; Sauter, O.; Silva, M.; TCV Team

2012-01-01

Scenarios with different electron cyclotron heating power profile distributions and widths were compared for the first time in experiments on the Tokamak à Configuration Variable (TCV). The heating profile was changed from shot to shot over a wide range from localized on-axis, with normalized minor radius half-width at half maximum σ1/2 ~ 0.1, up to a widely distributed heating power profile with σ1/2 ~ 0.4 and finally to a profile peaked far off-axis. The global confinement, MHD activity, density, temperature and electron pressure profile evolution were compared. In particular, the energy confinement properties of discharges with localized on-axis heating and distributed on-axis heating were very similar, with degradation close to that predicted by the ITER L-mode scaling; in the case of off-axis heating, on the other hand, the confinement degradation was even stronger.

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.

Spiral optical designs for nonimaging applications

NASA Astrophysics Data System (ADS)

Zamora, Pablo; Benítez, Pablo; Miñano, Juan C.; Vilaplana, Juan; Buljan, Marina

2011-10-01

Manufacturing technologies as injection molding or embossing specify their production limits for minimum radii of the vertices or draft angle for demolding, for instance. In some demanding nonimaging applications, these restrictions may limit the system optical efficiency or affect the generation of undesired artifacts on the illumination pattern. A novel manufacturing concept is presented here, in which the optical surfaces are not obtained from the usual revolution symmetry with respect to a central axis (z axis), but they are calculated as free-form surfaces describing a spiral trajectory around z axis. The main advantage of this new concept lies in the manufacturing process: a molded piece can be easily separated from its mold just by applying a combination of rotational movement around axis z and linear movement along axis z, even for negative draft angles. Some of these spiral symmetry examples will be shown here, as well as their simulated results.

Spiral nonimaging optical designs

NASA Astrophysics Data System (ADS)

Zamora, Pablo; Benítez, Pablo; Miñano, Juan C.; Vilaplana, Juan

2011-10-01

Manufacturing technologies as injection molding or embossing specify their production limits for minimum radii of the vertices or draft angle for demolding, for instance. In some demanding nonimaging applications, these restrictions may limit the system optical efficiency or affect the generation of undesired artifacts on the illumination pattern. A novel manufacturing concept is presented here, in which the optical surfaces are not obtained from the usual revolution symmetry with respect to a central axis (z axis), but they are calculated as free-form surfaces describing a spiral trajectory around z axis. The main advantage of this new concept lies in the manufacturing process: a molded piece can be easily separated from its mold just by applying a combination of rotational movement around axis z and linear movement along axis z, even for negative draft angles. Some of these spiral symmetry examples will be shown here, as well as their simulated results.

Novel freeform optical surface design with spiral symmetry

NASA Astrophysics Data System (ADS)

Zamora, Pablo; Benítez, Pablo; Miñano, Juan C.; Vilaplana, Juan

2011-10-01

Manufacturing technologies as injection molding or embossing specify their production limits for minimum radii of the vertices or draft angle for demolding, for instance. These restrictions may limit the system optical efficiency or affect the generation of undesired artifacts on the illumination pattern when dealing with optical design. A novel manufacturing concept is presented here, in which the optical surfaces are not obtained from the usual revolution symmetry with respect to a central axis (z axis), but they are calculated as free-form surfaces describing a spiral trajectory around z axis. The main advantage of this new concept lies in the manufacturing process: a molded piece can be easily separated from its mold just by applying a combination of rotational movement around axis z and linear movement along axis z, even for negative draft angles. The general designing procedure will be described in detail.

Do Concomitant Cranium and Axis Injuries Predict Worse Outcome? A Trauma Database Quantitative Analysis

PubMed Central

Chittiboina, Prashant; Banerjee, Anirban Deep; Nanda, Anil

2011-01-01

We performed a trauma database analysis to identify the effect of concomitant cranial injuries on outcome in patients with fractures of the axis. We identified patients with axis fractures over a 14-year period. A binary outcome measure was used. Univariate and multiple logistic regression analysis were performed. There were 259 cases with axis fractures. Closed head injury was noted in 57% and skull base trauma in 14%. Death occurred in 17 cases (6%). Seventy-two percent had good outcome. Presence of abnormal computed tomography head findings, skull base fractures, and visceral injury was significantly associated with poor outcome. Skull base injury in association with fractures of the axis is a significant independent predictor of worse outcomes, irrespective of the severity of the head injury. We propose that presence of concomitant cranial and upper vertebral injuries require careful evaluation in view of the associated poor prognosis. PMID:22470268

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."

Exploring system interconnection architectures with VIPACES: from direct connections to NOCs

NASA Astrophysics Data System (ADS)

Sánchez-Peña, Armando; Carballo, Pedro P.; Núñez, Antonio

2007-05-01

This paper presents a simple environment for the verification of AMBA 3 AXI systems in Verification IP (VIP) production called VIPACES (Verification Interface Primitives for the development of AXI Compliant Elements and Systems). These primitives are presented as a not compiled library written in SystemC where interfaces are the core of the library. The definition of interfaces instead of generic modules let the user construct custom modules improving the resources spent during the verification phase as well as easily adapting his modules to the AMBA 3 AXI protocol. This topic is the main discussion in the VIPACES library. The paper focuses on comparing and contrasting the main interconnection schemes for AMBA 3 AXI as modeled by VIPACES. For assessing these results we propose a validation scenario with a particular architecture belonging to the domain of MPEG4 video decoding, which is compound by an AXI bus connecting an IDCT and other processing resources.

Transition duct assembly with modified trailing edge in turbine system

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

McMahan, Kevin Weston; Schott, Carl Gerard; Ingram, Clint Luigie

2016-10-04

Transition duct assemblies for turbine systems and turbomachines are provided. In one embodiment, a transition duct assembly includes a plurality of transition ducts disposed in a generally annular array and comprising a first transition duct and a second transition duct. Each of the plurality of transition ducts includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of each transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct assembly further includes anmore » aerodynamic structure defined by the passages of the first transition duct and the second transition duct. The aerodynamic structure includes a pressure side, a suction side, and a trailing edge, the trailing edge having a modified aerodynamic contour.« less

Line-plane broadcasting in a data communications network of a parallel computer

DOEpatents

Archer, Charles J.; Berg, Jeremy E.; Blocksome, Michael A.; Smith, Brian E.

2010-06-08

Methods, apparatus, and products are disclosed for line-plane broadcasting in a data communications network of a parallel computer, the parallel computer comprising a plurality of compute nodes connected together through the network, the network optimized for point to point data communications and characterized by at least a first dimension, a second dimension, and a third dimension, that include: initiating, by a broadcasting compute node, a broadcast operation, including sending a message to all of the compute nodes along an axis of the first dimension for the network; sending, by each compute node along the axis of the first dimension, the message to all of the compute nodes along an axis of the second dimension for the network; and sending, by each compute node along the axis of the second dimension, the message to all of the compute nodes along an axis of the third dimension for the network.

Line-plane broadcasting in a data communications network of a parallel computer

DOEpatents

Archer, Charles J.; Berg, Jeremy E.; Blocksome, Michael A.; Smith, Brian E.

2010-11-23

Methods, apparatus, and products are disclosed for line-plane broadcasting in a data communications network of a parallel computer, the parallel computer comprising a plurality of compute nodes connected together through the network, the network optimized for point to point data communications and characterized by at least a first dimension, a second dimension, and a third dimension, that include: initiating, by a broadcasting compute node, a broadcast operation, including sending a message to all of the compute nodes along an axis of the first dimension for the network; sending, by each compute node along the axis of the first dimension, the message to all of the compute nodes along an axis of the second dimension for the network; and sending, by each compute node along the axis of the second dimension, the message to all of the compute nodes along an axis of the third dimension for the network.

Laser Measurements Based for Volumetric Accuracy Improvement of Multi-axis Systems

NASA Astrophysics Data System (ADS)

Vladimir, Sokolov; Konstantin, Basalaev

The paper describes a new developed approach to CNC-controlled multi-axis systems geometric errors compensation based on optimal error correction strategy. Multi-axis CNC-controlled systems - machine-tools and CMM's are the basis of modern engineering industry. Similar design principles of both technological and measurement equipment allow usage of similar approaches to precision management. The approach based on geometric errors compensation are widely used at present time. The paper describes a system for compensation of geometric errors of multi-axis equipment based on the new approach. The hardware basis of the developed system is a multi-function laser interferometer. The principles of system's implementation, results of measurements and system's functioning simulation are described. The effectiveness of application of described principles to multi-axis equipment of different sizes and purposes for different machining directions and zones within workspace is presented. The concepts of optimal correction strategy is introduced and dynamic accuracy control is proposed.

Dielectric waveguide with transverse index variation that support a zero group velocity mode at a non-zero longitudinal wavevector

DOEpatents

Ibanescu, Mihai; Joannopoious, John D.; Fink, Yoel; Johnson, Steven G.; Fan, Shanhui

2005-06-21

Optical components including a laser based on a dielectric waveguide extending along a waveguide axis and having a refractive index cross-section perpendicular to the waveguide axis, the refractive index cross-section supporting an electromagnetic mode having a zero group velocity for a non-zero wavevector along the waveguide axis.

A Simple Method to Determine the "R" or "S" Configuration of Molecules with an Axis of Chirality

ERIC Educational Resources Information Center

Wang, Cunde; Wu, Weiming

2011-01-01

A simple method for the "R" or "S" designation of molecules with an axis of chirality is described. The method involves projection of the substituents along the chiral axis, utilizes the Cahn-Ingold-Prelog sequence rules in assigning priority to the substituents, is easy to use, and has broad applicability. (Contains 5 figures.)

Coordinated X-Y stage apparatus

DOEpatents

Morimoto, Alan K.; Kozlowski, David M.; Charles, Steven T.; Spalding, James A.

2000-01-01

An apparatus based on precision X-Y stages that are stacked. Attached to arms projecting from each X-Y stage are a set of two axis gimbals. Attached to the gimbals is a rod, which provides motion along the axis of the rod and rotation around its axis. A dual-planar apparatus that provides six degrees of freedom of motion precise to within microns of motion.

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.

All MBE grown InAs/GaAs quantum dot lasers on on-axis Si (001).

PubMed

Kwoen, Jinkwan; Jang, Bongyong; Lee, Joohang; Kageyama, Takeo; Watanabe, Katsuyuki; Arakawa, Yasuhiko

2018-04-30

Directly grown III-V quantum dot (QD) laser on on-axis Si (001) is a good candidate for achieving monolithically integrated Si photonics light source. Nowadays, laser structures containing high quality InAs / GaAs QD are generally grown by molecular beam epitaxy (MBE). However, the buffer layer between the on-axis Si (001) substrate and the laser structure are usually grown by metal-organic chemical vapor deposition (MOCVD). In this paper, we demonstrate all MBE grown high-quality InAs/GaAs QD lasers on on-axis Si (001) substrates without using patterning and intermediate layers of foreign material.

Apparatus and method for delivering a fluid to a container

DOEpatents

Turner, Terry D.

2002-01-01

An apparatus for delivering a fluid into a container has a carriage movably associated with a holding mechanism along an axis. A piston is attached to the carriage and a cylinder is slidably attached to the piston along the axis. The cylinder has a hole formed therein that extends along the axis. A needle extending along the axis is attached to the piston and passes through the cylinder hole. The needle has a first operative position relative to the piston when the needle is retracted within the cylinder and a second operative position relative to the piston when the needle extends from the cylinder.

Method and device for determining the position of a cutting tool relative to the rotational axis of a spindle-mounted workpiece

DOEpatents

Williams, R.R.

1980-09-03

The present invention is directed to a method and device for determining the location of a cutting tool with respect to the rotational axis of a spindle-mounted workpiece. A vacuum cup supporting a machinable sacrificial pin is secured to the workpiece at a location where the pin will project along and encompass the rotational axis of the workpiece. The pin is then machined into a cylinder. The position of the surface of the cutting tool contacting the machine cylinder is spaced from the rotational axis of the workpiece a distance equal to the radius of the cylinder.

Measurement of νμ and νe Events in an Off-Axis Horn-Focused Neutrino Beam

NASA Astrophysics Data System (ADS)

Adamson, P.; Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Bishai, M.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J.; Choudhary, B. C.; Coney, L.; Conrad, J. M.; Cox, D. C.; Curioni, A.; Djurcic, Z.; Finley, D. A.; Fleming, B. T.; Ford, R.; Gallagher, H. R.; Garcia, F. G.; Garvey, G. T.; Green, C.; Green, J. A.; Harris, D.; Hart, T. L.; Hawker, E.; Hylen, J.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Kasper, P.; Katori, T.; Kobilarcik, T.; Kopp, S.; Kourbanis, I.; Koutsoliotas, S.; Laird, E. M.; Linden, S. K.; Link, J. M.; Liu, Y.; Liu, Y.; Loiacono, L.; Louis, W. C.; Marchionni, A.; Mahn, K. B. M.; Marsh, W.; McGregor, G.; Messier, M. D.; Metcalf, W.; Meyers, P. D.; Mills, F.; Mills, G. B.; Monroe, J.; Moore, C. D.; Nelson, J. K.; Nelson, R. H.; Nguyen, V. T.; Nienaber, P.; Nowak, J. A.; Ouedraogo, S.; Patterson, R. B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Prebys, E.; Raaf, J. L.; Ray, H.; Roe, B. P.; Russell, A. D.; Sandberg, V.; Schirato, R.; Schmitz, D.; Shaevitz, M. H.; Shoemaker, F. C.; Smart, W.; Smith, D.; Sodeberg, M.; Sorel, M.; Spentzouris, P.; Stancu, I.; Stefanski, R. J.; Sung, M.; Tanaka, H. A.; Tayloe, R.; Tzanov, M.; Vahle, P.; van de Water, R.; Viren, B.; Wascko, M. O.; White, D. H.; Wilking, M. J.; Yang, H. J.; Yumiceva, F. X.; Zeller, G. P.; Zimmerman, E. D.; Zwaska, R.

2009-05-01

We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3°) with respect to the NuMI beam axis. Samples of charged-current quasielastic νμ and νe interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.

Off-axis spectral beam combining of Bragg reflection waveguide photonic crystal diode lasers

NASA Astrophysics Data System (ADS)

Sun, Fangyuan; Wang, Lijie; Zhao, Yufei; Hou, Guanyu; Shu, Shili; Zhang, Jun; Peng, Hangyu; Tian, Sicong; Tong, Cunzhu; Wang, Lijun

2018-06-01

The spectral beam combining (SBC) of Bragg reflection waveguide photonic crystal (BRW-PC) diode lasers was studied for the first time. An off-axis feedback system was constructed using a stripe mirror and a spatial filter to control beam quality in the external cavity. It was found that the BRW-PC diode lasers with a low divergence and a circular beam provided a simplified and cost-effective SBC. The off-axis feedback broke the beam quality limit of a single element, and an M 2 factor of 3.8 times lower than that of a single emitter in the slow axis was demonstrated.

LOI/SOHO constraints on oblique rotation of the solar core

NASA Astrophysics Data System (ADS)

Gizon, L.; Appourchaux, T.; Gough, D. O.

The Sun is usually assumed to rotate about a single axis, tilted with respect to the ecliptic normal by an angle of 7.25 degrees. Although we have an excellent knowledge of the direction of the rotation axis of the photospheric layers, we cannot exclude a priori that the direction of the rotation axis could vary as a function of radius. We have tried to check whether the assumption of rotation about a unique axis is consistent with helioseismic data. We report on an attempt to measure the directions of the pulsation axes of several low-degree modes of oscillation in the LOI/SOHO Fourier spectra.

C-Axis-Oriented Hydroxyapatite Film Grown Using ZnO Buffer Layer

NASA Astrophysics Data System (ADS)

Sakoishi, Yasuhiro; Iguchi, Ryo; Nishikawa, Hiroaki; Hontsu, Shigeki; Hayami, Takashi; Kusunoki, Masanobu

2013-11-01

A method of fabricating c-axis-oriented hydroxyapatite film on a quartz crystal microbalance (QCM) sensor was investigated. ZnO was used as a template to obtain a hexagonal hydroxyapatite crystal of uniaxial orientation. The ZnO was grown as a c-axis film on a Au/quartz with the surface structure of a QCM sensor. Under optimized conditions, hydroxyapatite was deposited by pulsed laser deposition. X-ray diffraction showed the hydroxyapatite film to be oriented along the c-axis. Because Au and ZnO are applied to many devices, the anisotropic properties of hydroxyapatite may be incorporated into these devices as well as QCM sensors.

How do external companions affect spin-orbit misalignment of hot Jupiters?

NASA Astrophysics Data System (ADS)

Lai, Dong; Anderson, Kassandra R.; Pu, Bonan

2018-04-01

Consider a planet with its orbital angular momentum axis aligned with the spin axis of its host star. To what extent does an inclined distant companion (giant planet or binary star) affect this alignment? We provide an analytic, quantitative answer and apply it to hot Jupiter systems, for which misalignments between the orbital axis and the stellar spin axis have been detected. We also show how similar consideration can be applied to multiplanet systems with distant companions (such as Kepler-56). The result of this paper provides a simple method to assess the dynamical role played by external companions on spin-orbit misalignments in exoplanetary systems.

Research and development of a control system for multi axis cooperative motion based on PMAC

NASA Astrophysics Data System (ADS)

Guo, Xiao-xiao; Dong, Deng-feng; Zhou, Wei-hu

2017-10-01

Based on Programmable Multi-axes Controller (PMAC), a design of a multi axis motion control system for the simulator of spatial targets' dynamic optical properties is proposed. According to analysis the properties of spatial targets' simulator motion control system, using IPC as the main control layer, TurboPMAC2 as the control layer to meet coordinated motion control, data acquisition and analog output. A simulator using 5 servomotors which is connected with speed reducers to drive the output axis was implemented to simulate the motion of both the sun and the space target. Based on PMAC using PID and a notch filter algorithm, negative feedback, the speed and acceleration feed forward algorithm to satisfy the axis' requirements of the good stability and high precision at low speeds. In the actual system, it shows that the velocity precision is higher than 0.04 s ° and the precision of repetitive positioning is better than 0.006° when each axis is at a low-speed. Besides, the system achieves the control function of multi axis coordinated motion. The design provides an important technical support for detecting spatial targets, also promoting the theoretical research.

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.

A local autocrine axis in the testes that regulates spermatogenesis

PubMed Central

Cheng, C. Yan; Mruk, Dolores D.

2014-01-01

Spermiation—the release of mature spermatozoa from Sertoli cells into the seminiferous tubule lumen—occurs by the disruption of an anchoring device known as the apical ectoplasmic specialization (apical ES). At the same time, the blood–testis barrier (BTB) undergoes extensive restructuring to facilitate the transit of preleptotene spermatocytes. While these two cellular events take place at opposite ends of the Sertoli cell epithelium, the events are in fact tightly coordinated, as any disruption in either process will lead to infertility. A local regulatory axis exists between the apical ES and the BTB in which biologically active laminin fragments produced at the apical ES by the action of matrix metalloproteinase 2 can regulate BTB restructuring directly or indirectly via the hemidesmosome. Equally important, polarity proteins play a crucial part in coordinating cellular events within this apical ES–BTB–hemidesmosome axis. Additionally, testosterone and cytokines work in concert to facilitate BTB restructuring, which enables the transit of spermatocytes while maintaining immunological barrier function. Herein, we will discuss this important autocrine-based cellular axis that parallels the hormonal-based hypothalamic–pituitary–testicular axis that regulates spermatogenesis. This local regulatory axis is the emerging target for male contraception. PMID:20571538

Camber Angle Inspection for Vehicle Wheel Alignments

PubMed Central

Young, Jieh-Shian; Hsu, Hong-Yi; Chuang, Chih-Yuan

2017-01-01

This paper introduces an alternative approach to the camber angle measurement for vehicle wheel alignment. Instead of current commercial approaches that apply computation vision techniques, this study aims at realizing a micro-control-unit (MCU)-based camber inspection system with a 3-axis accelerometer. We analyze the precision of the inspection system for the axis misalignments of the accelerometer. The results show that the axes of the accelerometer can be aligned to the axes of the camber inspection system imperfectly. The calibrations that can amend these axis misalignments between the camber inspection system and the accelerometer are also originally proposed since misalignments will usually happen in fabrications of the inspection systems. During camber angle measurements, the x-axis or z-axis of the camber inspection system and the wheel need not be perfectly aligned in the proposed approach. We accomplished two typical authentic camber angle measurements. The results show that the proposed approach is applicable with a precision of ±0.015∘ and therefore facilitates the camber measurement process without downgrading the precision by employing an appropriate 3-axis accelerometer. In addition, the measured results of camber angles can be transmitted via the medium such as RS232, Bluetooth, and Wi-Fi. PMID:28165365

Calibrating accelerometer sensor on android phone with Accelerograph TDL 303 QS for earthquake online recorder

NASA Astrophysics Data System (ADS)

Riantana, R.; Darsono, D.; Triyono, A.; Azimut, H. B.

2016-11-01

Calibration of the android censor was done by placing the device in a mounting at side of accelerograph TDL 303 QS that will be a means of comparison. Leveling of both devices was set same, so that the state of the device can be assumed same anyway. Then applied vibrations in order to have the maximum amplitude value of both censor, so it can be found equality of the coefficient of proportionality both of them. The results on both devices obtain the Peak Ground Acceleration (PGA) as follows, on the x axis (EW) android censor is obtained PGA -2.4478145 gal than at TDL 303 QS obtained PGA -2.5504 gal, the y-axis (NS) on the censor android obtained PGA 3.0066964 gal than at TDL 303 QS obtained PGA 3.2073 gal, the z-axis (UD) on the android censor obtained PGA -14.0702377 gal than at TDL 303 QS obtained PGA -13.2927 gal, A correction value for android accelerometer censor is ± 0.1 gal for the x-axis (EW), ± 0.2 gal for the y-axis (NS), and ± 0.7 gal for the z-axis (UD).

Metabotropic glutamate receptor-mediated signaling dampens the HPA axis response to restraint stress

PubMed Central

Evanson, Nathan K.; Herman, James P.

2015-01-01

Glutamate is an important neurotransmitter in regulation of the neural portion of hypothalamus-pituitary-adrenal (HPA) axis activity, and signals through ionotropic and metabotropic receptors. In the current studies we investigated the role of hypothalamic paraventricular group I metabotropic glutamate receptors in regulation of the HPA axis response to restraint stress in rats. Direct injection of the group I metabotropic glutamate receptor agonist 3,5-dihydroxyphenylglycine (DHPG) into the PVN prior to restraint leads to blunting of the HPA axis response in awake animals. Consistent with this result, infusion of the group I receptor antagonist hexyl-homoibotenic acid (HIBO) potentiates the HPA axis response to restraint. The excitatory effect of blocking paraventricular group I metabotropic glutamate signaling is blocked by co-administration of dexamethasone into the PVN. However, the inhibitory effect of DHPG is not affected by co-administration of the cannabinoid CB1 receptor antagonist AM-251 into the PVN. Together, these results suggest that paraventricular group I metabotropic glutamate receptor signaling acts to dampen HPA axis reactivity. This effect appears to be similar to the rapid inhibitory effect of glucocorticoids at the PVN, but is not mediated by endocannabinoid signaling. PMID:25701594

Metabotropic glutamate receptor-mediated signaling dampens the HPA axis response to restraint stress.

PubMed

Evanson, Nathan K; Herman, James P

2015-10-15

Glutamate is an important neurotransmitter in the regulation of the neural portion of hypothalamus-pituitary-adrenal (HPA) axis activity, and signals through ionotropic and metabotropic receptors. In the current studies we investigated the role of hypothalamic paraventricular group I metabotropic glutamate receptors in the regulation of the HPA axis response to restraint stress in rats. Direct injection of the group I metabotropic glutamate receptor agonist 3,5-dihydroxyphenylglycine (DHPG) into the PVN prior to restraint leads to blunting of the HPA axis response in awake animals. Consistent with this result, infusion of the group I receptor antagonist hexyl-homoibotenic acid (HIBO) potentiates the HPA axis response to restraint. The excitatory effect of blocking paraventricular group I metabotropic glutamate signaling is blocked by co-administration of dexamethasone into the PVN. However, the inhibitory effect of DHPG is not affected by co-administration of the cannabinoid CB1 receptor antagonist AM-251 into the PVN. Together, these results suggest that paraventricular group I metabotropic glutamate receptor signaling acts to dampen HPA axis reactivity. This effect appears to be similar to the rapid inhibitory effect of glucocorticoids at the PVN, but is not mediated by endocannabinoid signaling. Copyright © 2015 Elsevier Inc. All rights reserved.

High-accuracy self-calibration method for dual-axis rotation-modulating RLG-INS

NASA Astrophysics Data System (ADS)

Wei, Guo; Gao, Chunfeng; Wang, Qi; Wang, Qun; Long, Xingwu

2017-05-01

Inertial navigation system has been the core component of both military and civil navigation systems. Dual-axis rotation modulation can completely eliminate the inertial elements constant errors of the three axes to improve the system accuracy. But the error caused by the misalignment angles and the scale factor error cannot be eliminated through dual-axis rotation modulation. And discrete calibration method cannot fulfill requirements of high-accurate calibration of the mechanically dithered ring laser gyroscope navigation system with shock absorbers. This paper has analyzed the effect of calibration error during one modulated period and presented a new systematic self-calibration method for dual-axis rotation-modulating RLG-INS. Procedure for self-calibration of dual-axis rotation-modulating RLG-INS has been designed. The results of self-calibration simulation experiment proved that: this scheme can estimate all the errors in the calibration error model, the calibration precision of the inertial sensors scale factor error is less than 1ppm and the misalignment is less than 5″. These results have validated the systematic self-calibration method and proved its importance for accuracy improvement of dual -axis rotation inertial navigation system with mechanically dithered ring laser gyroscope.

Hypothalamic-Pituitary-Adrenal Axis Programming after Recurrent Hypoglycemia during Development

PubMed Central

Rao, Raghavendra

2015-01-01

Permanent brain injury is a complication of recurrent hypoglycemia during development. Recurrent hypoglycemia also has adverse consequences on the neuroendocrine system. Hypoglycemia-associated autonomic failure, characterized by ineffective glucose counterregulation during hypoglycemia, is well described in children and adults on insulin therapy for diabetes mellitus. Whether recurrent hypoglycemia also has a programming effect on the hypothalamus-pituitary-adrenal cortex (HPA) axis has not been well studied. Hypoglycemia is a potent stress that leads to increased glucocorticoid secretion in all age groups, including the perinatal period. Other conditions associated with exposure to excess glucocorticoid in the perinatal period have a programming effect on the HPA axis activity. Limited animal data suggest the possibility of similar programming effect after recurrent hypoglycemia in the postnatal period. The age at exposure to hypoglycemia likely determines the HPA axis response in adulthood. Recurrent hypoglycemia in the early postnatal period likely leads to a hyperresponsive HPA axis, whereas recurrent hypoglycemia in the late postnatal period lead to a hyporesponsive HPA axis in adulthood. The age-specific programming effects may determine the neuroendocrine response during hypoglycemia and other stressful events in individuals with history of recurrent hypoglycemia during development. PMID:26343738

Relationship between adverse childhood experiences and homelessness and the impact of axis I and II disorders.

PubMed

Roos, Leslie E; Mota, Natalie; Afifi, Tracie O; Katz, Laurence Y; Distasio, Jino; Sareen, Jitender

2013-12-01

We investigated the links between homelessness associated with serious mental and physical healthy disparities and adverse childhood experiences (ACEs) in nationally representative data, with Axis I and II disorders as potential mediators. We examined data from the National Epidemiologic Survey of Alcohol and Related Conditions in 2001-2002 and 2004-2005, and included 34,653 participants representative of the noninstitutionalized US population who were 20 years old or older. We studied the variables related to 4 classes of Axis I disorders, all 10 Axis II personality disorders, a wide range of ACEs, and a lifetime history of homelessness. Analyses revealed high prevalences of each ACE in individuals experiencing lifetime homelessness (17%-60%). A mediation model with Axis I and II disorders determined that childhood adversities were significantly related to homelessness through direct effects (adjusted odd ratios = 2.04, 4.24) and indirect effects, indicating partial mediation. Population attributable fractions were also reported. Although Axis I and II disorders partially mediated the relationship between ACEs and homelessness, a strong direct association remained. This novel finding has implications for interventions and policy. Additional research is needed to understand relevant causal pathways.

Stimuli-Driven Control of the Helical Axis of Self-Organized Soft Helical Superstructures.

PubMed

Bisoyi, Hari Krishna; Bunning, Timothy J; Li, Quan

2018-06-01

Supramolecular and macromolecular functional helical superstructures are ubiquitous in nature and display an impressive catalog of intriguing and elegant properties and performances. In materials science, self-organized soft helical superstructures, i.e., cholesteric liquid crystals (CLCs), serve as model systems toward the understanding of morphology- and orientation-dependent properties of supramolecular dynamic helical architectures and their potential for technological applications. Moreover, most of the fascinating device applications of CLCs are primarily determined by different orientations of the helical axis. Here, the control of the helical axis orientation of CLCs and its dynamic switching in two and three dimensions using different external stimuli are summarized. Electric-field-, magnetic-field-, and light-irradiation-driven orientation control and reorientation of the helical axis of CLCs are described and highlighted. Different techniques and strategies developed to achieve a uniform lying helix structure are explored. Helical axis control in recently developed heliconical cholesteric systems is examined. The control of the helical axis orientation in spherical geometries such as microdroplets and microshells fabricated from these enticing photonic fluids is also explored. Future challenges and opportunities in this exciting area involving anisotropic chiral liquids are then discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kisspeptin regulates the hypothalamus-pituitary-gonad axis gene expression during sexual maturation in the cinnamon clownfish, Amphiprion melanopus.

PubMed

Kim, Na Na; Shin, Hyun Suk; Choi, Young Jae; Choi, Cheol Young

2014-02-01

Kisspeptins (Kiss) have been recognized as potent regulators of reproduction in teleosts, and Kiss is suggested to be a key regulator of the hypothalamus-pituitary-gonad axis (HPG). However, its regulatory role on reproduction in fish remains unclear. Therefore, to investigate the role of Kiss on fish reproduction, this study aimed to test differences in the hormones of the HPG axis, Kiss as neuropeptides, and sex steroids on the sexual maturation of paired cinnamon clownfish, Amphiprion melanopus, following treatment with Kiss. We investigated the actions of sex maturation hormones, including HPG axis hormones and sex steroid hormones, such as gonadotropin-releasing hormones, gonadotropin hormones (GTHs), GTH receptors, estrogen receptors, and vitellogenin in the pituitary, gonads, and liver following treatment with Kiss. The expression levels of HPG axis genes increased after the Kiss injection. In addition, the levels of plasma 17α-hydroxypregnenolone, estradiol-17β, and 11-ketotestosterone increased. These results support the hypothesis that Kiss play important roles in the regulation of the HPG axis and are most likely involved in gonadal development and sexual maturation in cinnamon clownfish. Copyright © 2013 Elsevier Inc. All rights reserved.

Hypothalamic-Pituitary-Adrenal Axis Programming after Recurrent Hypoglycemia during Development.

PubMed

Rao, Raghavendra

2015-08-28

Permanent brain injury is a complication of recurrent hypoglycemia during development. Recurrent hypoglycemia also has adverse consequences on the neuroendocrine system. Hypoglycemia-associated autonomic failure, characterized by ineffective glucose counterregulation during hypoglycemia, is well described in children and adults on insulin therapy for diabetes mellitus. Whether recurrent hypoglycemia also has a programming effect on the hypothalamus-pituitary-adrenal cortex (HPA) axis has not been well studied. Hypoglycemia is a potent stress that leads to increased glucocorticoid secretion in all age groups, including the perinatal period. Other conditions associated with exposure to excess glucocorticoid in the perinatal period have a programming effect on the HPA axis activity. Limited animal data suggest the possibility of similar programming effect after recurrent hypoglycemia in the postnatal period. The age at exposure to hypoglycemia likely determines the HPA axis response in adulthood. Recurrent hypoglycemia in the early postnatal period likely leads to a hyperresponsive HPA axis, whereas recurrent hypoglycemia in the late postnatal period lead to a hyporesponsive HPA axis in adulthood. The age-specific programming effects may determine the neuroendocrine response during hypoglycemia and other stressful events in individuals with history of recurrent hypoglycemia during development.

Method and apparatus for manufacturing high-accuracy radio telescope reflector panels

NASA Astrophysics Data System (ADS)

Bosma, Marinus B.

1998-07-01

This article covers the manufacturing of aluminum reflector panels for submillimeter radio astronomy. The first part involves the general construction and application of a machine custom designed and built to do this. The second is a discussion of the software and execution of method to actually produce the reflectors for the Smithsonian Astrophysical Observatories Submillimeter Array (SMA). The reflective surface of each panel is contoured both radially and circularly by oscillating a platen supporting the panel about a fixed axis relative to a tool which is fixed during platen oscillation. The tool is repositionable between oscillations along an x axis to achieve the radial contour and along a z axis to achieve the desired parabolic or spherical contour. Contrary to the normal contouring of such a surface with a 5- axis CNC machine, tool positioning along either axis is independent of tool location along the other axis, simplifying the machine structure as well as its computerized operation. A unique hinge is provided to restrain the platen in a radial direction while allowing floating action of the platen on an air cushion during its oscillation. These techniques and the equipment are documented in U.S. Patent No. 5477602.

Subendocardial motion in hypertrophic cardiomyopathy: assessment from long- and short-axis views by pulsed tissue Doppler imaging

NASA Technical Reports Server (NTRS)

Tabata, T.; Oki, T.; Yamada, H.; Abe, M.; Onose, Y.; Thomas, J. D.

2000-01-01

BACKGROUND: Tissue Doppler imaging (TDI) is a recently developed technique that allows the instantaneous measurement of intrinsic regional myocardial motion velocity. Pulsed TDI is capable of separately assessing left ventricular (LV) regional motion velocity caused by circumferential and longitudinal fiber contraction. This particular feature of function is still controversial in patients with hypertrophic cardiomyopathy (HC). METHODS: To better characterize intrinsic circumferential and longitudinal LV systolic myocardial function in HC, we used pulsed TDI to measure short- and long-axis LV motion velocities, respectively. The subendocardial motion velocity patterns at the middle of the LV posterior wall (PW) and ventricular septum (IVS) in LV parasternal and apical long-axis views were recorded by pulsed TDI in 19 patients with nonobstructive HC and in 21 normal controls (NC). RESULTS: Peak short- and long-axis systolic subendocardial velocities in both the LV PW and IVS were significantly smaller in the HC group than in the NC group, and the time to peak velocity was significantly delayed. Furthermore, peak PW systolic velocity was significantly greater along the long axis than along the short axis in the NC group (8.8 +/- 1.5 cm/s vs 8.2 +/- 1.4 cm/s, P <.05), whereas the opposite was observed in the HC group (6.1 +/- 1.2 cm/s vs 7.5 +/- 1.0 cm/s, P <.0001). No significant differences were found in either group between the long- and short-axis IVS velocities (HC: 5.9 +/- 1.4 cm/s vs 5.5 +/- 1.3 cm/s; NC: 7.8 +/- 1.3 cm/s vs 7.9 +/- 1.6 cm/s). CONCLUSIONS: By using the capability of pulsed TDI for the evaluation of intrinsic myocardial velocity instantaneously in a specific region and direction, we found impairment of LV myocardial systolic function in patients with HC not only in the hypertrophied IVS but also in the nonhypertrophied LV PW. We also found a greater decrease in LV PW velocities along the long axis than the short axis, suggesting greater impairment of long-axis contraction in patients with HC. Because our HC patients did not appear to have excessive intracavitary pressure, these results suggest that the relatively normal-appearing PW is directly affected by the HC pathologic process.

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, the blanks were positioned at a large off-axis distance and angle, and the axis of the FTS was not parallel to the axis of the spindle of the SPDT machine. The spindle was rotated at a speed of 120 rpm, and the maximum FTS speed was 8.2 mm/s.

Caffeine enhances the speed of the recovery of the hypothalamo-pituitary-adrenocortical axis after chronic prednisolone administration in the rat.

PubMed

Marzouk, H F; Zuyderwijk, J; Uitterlinden, P; van Koetsveld, P; Blijd, J J; Abou-Hashim, E M; el-Kannishy, M H; de Jong, F H; Lamberts, S W

1991-11-01

Chronic administration of corticosteroids results in a suppression of the hypothalamo-pituitary-adrenocortical (HPA) axis. The time course of the recovery of the HPA axis depends on the dose and duration of corticosteroid administration. We investigated the recovery of the HPA axis after 14 days of prednisolone administration to rats at a dose of 2.0 mg/rat/day via the drinking water (188 mumol/l). The in vitro corticosterone production by dispersed adrenal cells in response to increasing concentrations of ACTH had recovered 3 days after stopping prednisolone administration. In parallel the initially suppressed plasma corticosterone concentrations had recovered after 3 days, while the pituitary ACTH content had recovered after 5 days. We investigated the possibility to enhance the speed of the recovery of the HPA axis by the simultaneous administration of two drugs with known CRF-stimulating activity via the drinking water. Caffeine in a dose of 100 mg/kg body weight enhanced the recovery of the prednisolone-suppressed HPA axis significantly. One day after the end of prednisolone administration a significant increase in the adrenal weight, in the corticosterone production by dispersed adrenal cells, as well as in the plasma corticosterone concentrations, and in the pituitary ACTH content was observed in the caffeine-treated rats. Chlorimipramine (20 mg/kg body weight), on the other hand, did not influence the prednisolone-mediated suppression of the HPA axis.(ABSTRACT TRUNCATED AT 250 WORDS)

Klotho and the Growth Hormone/Insulin-Like Growth Factor 1 Axis: Novel Insights into Complex Interactions.

PubMed

Rubinek, T; Modan-Moses, D

2016-01-01

The growth hormone (GH)/insulin-like growth factor (IGF)-1 axis is pivotal for many metabolic functions, including proper development and growth of bones, skeletal muscles, and adipose tissue. Defects in the axis' activity during childhood result in growth abnormalities, while increased secretion of GH from the pituitary results in acromegaly. In order to keep narrow physiologic concentration, GH and IGF-1 secretion and activity are tightly regulated by hypothalamic, pituitary, endocrine, paracrine, and autocrine factors. Klotho was first discovered as an aging-suppressor gene. Mice that do not express klotho die prematurely with multiple symptoms of aging, several of them are also characteristic of decreased GH/IGF-1 axis activity. Klotho is highly expressed in the brain, the kidney, and parathyroid and pituitary glands, but can also serve as a circulating hormone by its shedding, forming soluble klotho that can be detected in blood, cerebrospinal fluid, and urine. Several lines of evidence suggest an association between klotho levels and activity of the GH/IGF-1 axis: the GH-secreting cells in the anterior pituitary of klotho-deficient mice are hypotrophic; klotho levels are altered in subjects with pathologies of the GH/IGF-1 axis; and accumulating data indicate that klotho is a direct regulator of GH secretion. Thus, klotho seems to be a new player in the intricate regulation of the GH/IGF-1 axis. © 2016 Elsevier Inc. All rights reserved.

Development of sacrificial support fixture using deflection analysis

NASA Astrophysics Data System (ADS)

Ramteke, Ashwini M.; Ashtankar, Kishor M.

2018-04-01

Sacrificial support fixtures are the structures used to hold the part during machining while rotating the part about the fourth axis of CNC machining. In Four axis CNC machining part is held in a indexer which is rotated about the fourth axis of rotation. So using traditional fixturing devices to hold the part during machining such as jigs, v blocks and clamping plates needs a several set ups, manufacturing time which increase the cost associated with it. Since the part is rotated about the axis of rotation in four axis CNC machining so using traditional fixturing devices to hold the part while machining we need to reorient the fixture each time for particular orientation of part about the axis of rotation. So our proposed methodology of fixture design eliminates the cost associate with the complicated fixture design for customized parts which in turn reduces the time of manufacturing of the fixtures. But while designing the layout of the fixtures it is found out that the machining the part using four axis CNC machining the accurate machining of the part is directly proportional to the deflection produced in a part. So to machine an accurate part the deflection produced in a part should be minimum. We assume that the deflection produced in a part is a result of the deflection produced in a sacrificial support fixture while machining. So this paper provides the study of the deflection checking in a part machined using sacrificial support fixture by using FEA analysis.

The Effect of Microgravity on the Growth of Lead Tin Telluride

NASA Technical Reports Server (NTRS)

Narayanan, R.

2000-01-01

The main objective of this research was to present a model for the prediction of the effect of the microgravity environment on the growth of Lead Tin Telluride. The attitude change and its relation to the experimental objectives: The main objective for the AADSF experiment on USMP 3 involving LTT growth was to estimate the effect of ampoule orientation on the axial and radial segregation of tin telluride. As the furnace was not situated on a gimbal there was no possibility to reorient the ampoule during the flight. Instead the only way to change the growth orientation was to change the attitude of the orbiter. This was accomplished by vernier rocket firings. In what follows it must be noted that the orbiter body coordinates are such that the positive z axis points outward from the 'belly', the positive 'x' axis points outwards from the nose and the positive 'y' axis points outwards from the starboard side. The furnace which was in the pay load had its axis aligned with the orbiter's 'z' axis with the hot end closest to the shuttle body. There were basically three orientations that were desired. These corresponded to the ampoule being seen as a heated from above (thermally stable-solutally unstable) configuration, the heated from below (where the instabilities were reversed from the first orientation) configuration and an 'in between' case where the ampoule axis was misaligned with respect to the orbiters 'g(sub z)' axis.

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.

Photoactivation of Akt1/GSK3β Isoform-Specific Signaling Axis Promotes Pancreatic β-Cell Regeneration.

PubMed

Huang, Lei; Jiang, Xiaoxiao; Gong, Longlong; Xing, Da

2015-08-01

Promotion of insulin-secreting β-cell regeneration in patients with diabetes is a promising approach for diabetes therapy, which can contribute to rescue the uncontrolled hyperglycemia. Low-power laser irradiation (LPLI) has been demonstrated to regulate multiple physiological processes both in vitro and in vivo through activation of various signaling pathways. In the present study, we showed that LPLI promoted β-cell replication and cell cycle progression through activation of Akt1/GSK3β isoform-specific signaling axis. Inhibition of PI3-K/Akt or GSK3 with specific inhibitors dramatically reduced or increased LPLI-induced β-cell replication, revealing Akt/GSK3 signaling axis was involved in β-cell replication and survival upon LPLI treatment. Furthermore, the results of shRNA-mediated knock down of Akt/GSK3 isoforms revealed that Akt1/GSK3β isoform-specific signaling axis regulated β-cell replication and survival in response to LPLI, but not Akt2/GSK3α. The mechanism by which LPLI promoted β-cell replication through Akt1/GSK3β signaling axis involved activation of β-catenin and down-regulation of p21. Taken together, these observations suggest that Akt1/GSK3β isoform signaling axis play a key role in β-cell replication and survival induced by LPLI. Moreover, our findings suggest that activation of Akt1/GSK3β isoform signaling axis by LPLI may provide guidance in practical applications for β-cell regenerative therapies. © 2015 Wiley Periodicals, Inc.

Evaluation of the prototype dual-axis wall attitude measurement sensor

NASA Technical Reports Server (NTRS)

Wong, Douglas T.

1994-01-01

A prototype dual-axis electrolytic tilt sensor package for angular position measurements was built and evaluated in a laboratory environment. The objective was to investigate the use of this package for making wind tunnel wall attitude measurements for the National Transonic Facility (NTF) at NASA Langley Research Center (LaRC). The instrumentation may replace an existing, more costly, and less rugged servo accelerometer package (angle-of-attack package) currently in use. The dual-axis electrolytic tilt sensor package contains two commercial electrolytic tilt sensors thermally insulated with NTF foam, all housed within a stainless steel package. The package is actively heated and maintained at 160 F using foil heating elements. The laboratory evaluation consisted of a series of tests to characterize the linearity, repeatability, cross-axis interaction, lead wire effect, step response, thermal time constant, and rectification errors. Tests revealed that the total RMS errors for the x-axis sensor is 0.084 degree, and 0.182 degree for the y-axis sensor. The RMS errors are greater than the 0.01 degree specification required for NTF wall attitude measurements. It is therefore not a viable replacement for the angle-of-attack package in the NTF application. However, with some physical modifications, it can be used as an inexpensive 5-degree range dual-axis inclinometer with overall accuracy approaching 0.01 degree under less harsh environments. Also, the data obtained from the tests can be valuable for wind tunnel applications of most types of electrolytic tilt sensors.

Novel process for production of micro lenses with increased centering accuracy and imaging performance

NASA Astrophysics Data System (ADS)

Wilde, C.; Langehanenberg, P.; Schenk, T.

2017-10-01

For modern production of micro lens systems, such as cementing of doublets or more lenses, precise centering of the lens edge is crucial. Blocking the lens temporarily on a centering arbor ensures that the centers of all optical lens surfaces coincide with the lens edge, while the arbor's axis serves as reference for both alignment and edging process. This theoretical assumption of the traditional cementing technology is not applicable for high-end production. In reality cement wedges between the bottom lens surface and the arbor's ring knife edge may occur and even expensive arbors with single-micron precision suffer from reduced quality of the ring knife edge after multiple usages and cleaning cycles. Consequently, at least the position of the bottom lens surface is undefined and the optical axis does not coincide with the arbor's reference axis! In order to overcome this basic problem in using centering arbors, we present a novel and efficient technique which can measure and align both surfaces of a lens with respect to the arbor axis with high accuracy and furthermore align additional lenses to the optical axis of the bottom lens. This is accomplished by aligning the lens without mechanical contact to the arbor. Thus the lens can be positioned in four degrees of freedom, while the centration errors of all lens surfaces are measured and considered. Additionally the arbor's reference axis is not assumed to be aligned to the rotation axis, but simultaneously measured with high precision.

Cushing's Syndrome and Hypothalamic-Pituitary-Adrenal Axis Hyperactivity in Chronic Central Serous Chorioretinopathy.

PubMed

van Haalen, Femke M; van Dijk, Elon H C; Dekkers, Olaf M; Bizino, Maurice B; Dijkman, Greet; Biermasz, Nienke R; Boon, Camiel J F; Pereira, Alberto M

2018-01-01

Central serous chorioretinopathy (CSC), a specific form of macular degeneration, has been reported as presenting manifestation of Cushing's syndrome. Furthermore, CSC has been associated with both exogenous hypercortisolism and endogenous Cushing's syndrome. It is important to know whether CSC patients should be screened for Cushing's syndrome. Although hypothalamic-pituitary-adrenal (HPA) axis hyperactivity in CSC has been suggested, no detailed evaluation of the HPA axis has been performed in a large cohort of CSC patients. This study aimed to investigate whether Cushing's syndrome prevalence is increased among chronic CSC (cCSC) patients and whether detailed endocrinological phenotyping indicates hyperactivity of the HPA axis. Cross-sectional study. 86 cCSC patients and 24 controls. Prevalence of Cushing's syndrome, HPA axis activity. None of the cCSC patients met the clinical or biochemical criteria of Cushing's syndrome. However, compared to controls, HPA axis activity was increased in cCSC patients, reflected by higher 24 h urinary free cortisol, and accompanying higher waist circumference and diastolic blood pressure, whereas circadian cortisol rhythm and feedback were not different. Chronic CSC patients did not report more stress or stress-related problems on questionnaires. No case of Cushing's syndrome was revealed in a large cohort of cCSC patients. Therefore, we advise against screening for Cushing's syndrome in CSC patients, unless additional clinical features are present. However, our results indicate that cCSC is associated with hyperactivity of the HPA axis, albeit not accompanied with perception of more psychosocial stress.

Elliptic nozzle aspect ratio effect on controlled jet propagation

NASA Astrophysics Data System (ADS)

Aravindh Kumar, S. M.; Rathakrishnan, Ethirajan

2017-04-01

The present study deals with the control of a Mach 2 elliptic jet from a convergent-divergent elliptic nozzle of aspect ratio 4 using tabs at the nozzle exit. The experiments were carried out for rectangular and triangular tabs of the same blockage, placed along the major and minor axes of the nozzle exit, at different levels of nozzle expansion. The triangular tabs along the minor axis promoted superior mixing compared to the other controlled jets and caused substantial core length reduction at all the nozzle pressure ratios studied. The rectangular tabs along the minor axis caused core length reduction at all pressure ratios, but the values were minimal compared to that of triangular tabs along the minor axis. For all the test conditions, the mixing promotion caused by tabs along the major axis was inferior to that of tabs along the minor axis. The waves present in the core of controlled jets were visualized using a shadowgraph. Comparison of the present results with the results of a controlled Mach 2 elliptic jet of aspect ratio 2 (Aravindh Kumar and Sathakrishnan 2016 J. Propulsion Power 32 121-33, Aravindh Kumar and Rathakrishnan 2016 J. Aerospace Eng. at press (doi:10.1177/0954410016652921)) show that for all levels of expansion, the mixing effectiveness of triangular tabs along the minor axis of an aspect ratio 4 nozzle is better than rectangular or triangular tabs along the minor axis of an aspect ratio 2 nozzle.

A polar-region-adaptable systematic bias collaborative measurement method for shipboard redundant rotational inertial navigation systems

NASA Astrophysics Data System (ADS)

Wang, Lin; Wu, Wenqi; Wei, Guo; Lian, Junxiang; Yu, Ruihang

2018-05-01

The shipboard redundant rotational inertial navigation system (RINS) configuration, including a dual-axis RINS and a single-axis RINS, can satisfy the demand of marine INSs of especially high reliability as well as achieving trade-off between position accuracy and cost. Generally, the dual-axis RINS is the master INS, and the single-axis RINS is the hot backup INS for high reliability purposes. An integrity monitoring system performs a fault detection function to ensure sailing safety. However, improving the accuracy of the backup INS in case of master INS failure has not been given enough attention. Without the aid of any external information, a systematic bias collaborative measurement method based on an augmented Kalman filter is proposed for the redundant RINSs. Estimates of inertial sensor biases can be used by the built-in integrity monitoring system to monitor the RINS running condition. On the other hand, a position error prediction model is designed for the single-axis RINS to estimate the systematic error caused by its azimuth gyro bias. After position error compensation, the position information provided by the single-axis RINS still remains highly accurate, even if the integrity monitoring system detects a dual-axis RINS fault. Moreover, use of a grid frame as a navigation frame makes the proposed method applicable in any area, including the polar regions. Semi-physical simulation and experiments including sea trials verify the validity of the method.

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.

Improved Controller for a Three-Axis Piezoelectric Stage

NASA Technical Reports Server (NTRS)

Rao, Shanti; Palmer, Dean

2009-01-01

An improved closed-loop controller has been built for a three-axis piezoelectric positioning stage. The stage can be any of a number of commercially available or custom-made units that are used for precise three-axis positioning of optics in astronomical instruments and could be used for precise positioning in diverse fields of endeavor that include adaptive optics, fabrication of semiconductors, and nanotechnology.

Solar energy system with wind vane

DOEpatents

Grip, Robert E

2015-11-03

A solar energy system including a pedestal defining a longitudinal axis, a frame that is supported by the pedestal and that is rotateable relative to the pedestal about the longitudinal axis, the frame including at least one solar device, and a wind vane operatively connected to the frame to urge the frame relative to the pedestal about the longitudinal axis in response to wind acting on the wind vane.

The Life and Death of Axis IV: Caught in the Quest for a Theory of Mental Disorder

ERIC Educational Resources Information Center

Probst, Barbara

2014-01-01

Axis IV, one of the five dimensions of clinical description, has provided a way to report psychosocial and environmental problems that may affect the diagnosis, treatment, and/or prognosis of a psychiatric disorder. Originally conceived in DSM-III as a way to rate and rank the severity of particular environmental stressors, axis IV was simplified…

Pulsed ultrasonic stir welding system

NASA Technical Reports Server (NTRS)

Ding, R. Jeffrey (Inventor)

2013-01-01

An ultrasonic stir welding system includes a welding head assembly having a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. During a welding operation, ultrasonic pulses are applied to the rod as it rotates about its longitudinal axis. The ultrasonic pulses are applied in such a way that they propagate parallel to the longitudinal axis of the rod.

OD Covariance in Conjunction Assessment: Introduction and Issues

NASA Technical Reports Server (NTRS)

Hejduk, M. D.; Duncan, M.

2015-01-01

Primary and secondary covariances combined and projected into conjunction plane (plane perpendicular to relative velocity vector at TCA) Primary placed on x-axis at (miss distance, 0) and represented by circle of radius equal to sum of both spacecraft circumscribing radiiZ-axis perpendicular to x-axis in conjunction plane Pc is portion of combined error ellipsoid that falls within the hard-body radius circle

Analysis of Ejection Seat Stability Using Easy Program. Volume I.

DTIC Science & Technology

1980-09-01

BODY AXiS FURCE COMPONENT. L ACTING ON THE AiRPLANc FROM THE CATAPULT (Ld) C ILA1(3) - PORT ONE X,Y,L AIRPLANE BODY AXIS TORQUE COMPONENTS C ACrINu...THE AIRPLANE (FT) C EAPI3) - EARTH TO AIRPLANc . EULER ANGLES (DEG) C SKPt3) - XtYZ EARTh POSITIGN VECTOR OF THE SEAT REFERENCE L POINT (FT) f- LST(3

Rotor assembly including superconducting magnetic coil

DOEpatents

Snitchler, Gregory L.; Gamble, Bruce B.; Voccio, John P.

2003-01-01

Superconducting coils and methods of manufacture include a superconductor tape wound concentrically about and disposed along an axis of the coil to define an opening having a dimension which gradually decreases, in the direction along the axis, from a first end to a second end of the coil. Each turn of the superconductor tape has a broad surface maintained substantially parallel to the axis of the coil.

Single nucleotide polymorphisms in the growth hormone - insulin like growth factor axis in straight bred and crossbred Angus, Brahman, and Romosinuano heifers: population genetic analyses and association of genotypes

USDA-ARS?s Scientific Manuscript database

The growth endocrine axis influences reproduction. Objectives of this study were to evaluate population genetic characteristics of SNP genotypes within genes of the GH and IGF axis in straightbred and diallel-crossed Angus, Brahman and Romosinuano heifers (n = 650) and to test the associations of th...

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.

Malaligned dynamic anterior cervical plate: a biomechanical analysis of effectiveness.

PubMed

Lawrence, Brandon D; Patel, Alpesh A; Guss, Andrew; Ryan Spiker, W; Brodke, Darrel S

2014-12-01

Biomechanical evaluation. To evaluate the kinematic and load-sharing differences of dynamic anterior cervical plates when placed in-line at 0° and off-axis at 20°. The use of dynamic anterior cervical plating systems has recently gained popularity due to the theoretical benefit of improved load sharing with graft subsidence. Occasionally, due to anatomical restraints, the anterior cervical plate may be placed off-axis in the coronal plane. This may potentially decrease the dynamization capability of the plate, leading to less load sharing and potentially decreased fusion rates. The purpose of this study was to comprehensively evaluate the kinematic and load-sharing differences of a dynamic plate placed in-line versus off-axis in the coronal plane. Thirteen fresh-frozen human cadaveric cervical spines (C2-T1) were used. Nondestructive range-of-motion testing was performed with a pneumatically controlled spine simulator in flexion/extension, lateral bending, and axial rotation using the OptoTrak motion measurement system. A C5 corpectomy was performed, and a custom interbody spacer with an integrated load cell collected load-sharing data under axial compression at varying loads. A dynamic anterior cervical plate was placed in-line at 0° and then off-axis at 20°. Testing conditions ensued using a full-length spacer, followed by simulated subsidence by removing 10% of the height of the original spacer. There were no kinematic differences noted in the in-line model versus the off-axis model. After simulated subsidence, the small decreases in stiffness and increases in motion were similar whether the plate was placed in-line or off-axis in all 3 planes of motion. There were also no significant differences in the load-sharing characteristics of the in-line plate versus the off-axis plate in either the full-length model or the subsided interbody model. This study suggests that off-axis dynamic plate positioning does not significantly impact construct kinematics or graft load sharing. As such, we do not recommend removal or repositioning of an off-axis placed dynamic plate because the kinematic and load-sharing biomechanical properties are similar. N/A.

Responses of neurons in the medial column of the inferior olive in pigeons to translational and rotational optic flowfields.

PubMed

Winship, I R; Wylie, D R

2001-11-01

The responses of neurons in the medial column of the inferior olive to translational and rotational optic flow were recorded from anaesthetized pigeons. Panoramic translational or rotational flowfields were produced by mechanical devices that projected optic flow patterns onto the walls, ceiling and floor of the room. The axis of rotation/translation could be positioned to any orientation in three-dimensional space such that axis tuning could be determined. Each neuron was assigned a vector representing the axis about/along which the animal would rotate/translate to produce the flowfield that elicited maximal modulation. Both translation-sensitive and rotation-sensitive neurons were found. For neurons responsive to translational optic flow, the preferred axis is described with reference to a standard right-handed coordinate system, where +x, +y and +z represent rightward, upward and forward translation of the animal, respectively (assuming that all recordings were from the right side of the brain). t(+y) neurons were maximally excited in response to a translational optic flowfield that results from self-translation upward along the vertical (y) axis. t(-y) neurons also responded best to translational optic flow along the vertical axis but showed the opposite direction preference. The two remaining groups, t(-x+z) and t(-x-z) neurons, responded best to translational optic flow along horizontal axes that were oriented 45 degrees to the midline. There were two types of neurons responsive to rotational optic flow: rVA neurons preferred rotation about the vertical axis, and rH135c neurons preferred rotation about a horizontal axis at 135 degrees contralateral azimuth. The locations of marking lesions indicated a clear topographical organization of the six response types. In summary, our results reinforce that the olivo-cerebellar system dedicated to the analysis of optic flow is organized according to a reference frame consisting of three approximately orthogonal axes: the vertical axis, and two horizontal axes oriented 45 degrees to either side the midline. Previous research has shown that the eye muscles, vestibular semicircular canals and postural control system all share a similar spatial frame of reference.

Influence of tumor location on the intensity-modulated radiation therapy plan of helical tomotherapy.

PubMed

Xu, Yingjie; Yan, Hui; Hu, Zhihui; Ma, Pan; Men, Kuo; Huang, Peng; Ren, Wenting; Dai, Jianrong; Li, Yexiong

2017-01-01

Given the design of the Helical TomoTherapy device, the patient's central axis is routinely aligned with the machine's rotational axis to prevent the patient's body from colliding with the machine walls. However, for treatment of tumors located away from the patient's central axis, this position may not be optimal as the adequate radiation dose may not reach the affected site. Our study aimed to investigate the influence of tumor location on dose quality and delivery efficiency of tomotherapy plans. A phantom and 15 patients were selected for this study. Two plans, A and B, were implemented for each case. In plan A, the patient's central axis was aligned with the machine's rotational axis, whereas in plan B, the center of the planning target volume (PTV) was aligned with the machine's rotational axis. Both plans were optimized with the same planning parameters, and the dose quality of the plans was evaluated using dosimetrics. The delivery efficiency was determined from delivery time and monitor units (MUs). A paired t-test or nonparametric Wilcoxon signed-rank test was performed for statistical comparison. In the phantom study, the median delivery times were 358 and 336 seconds for plans A and B, respectively, and this difference was significant (p = 0.005). In the patient study, the median delivery times were 348 and 317 seconds for plans A and B, respectively, and this difference was also significant (p = 0.001). The dose qualities of both plans for each patient were nearly identical. No significant differences were found in the conformal index, heterogeneity index, and mean dose delivered to normal tissue between the plans. Both phantom and patient studies showed that for normal-sized patients, the delivery time reduced as the distance between the PTV and the patient's central axis increased when the PTV center was aligned with the machine axis. In conclusion, aligning the PTV center with the machine's rotational axis by shifting the patient during tomotherapy reduces the delivery time without compromising the dose quality of intensity-modulated radiation therapy. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Structure and Dynamics of the Southeast Indian Ridge and Off-axis Volcanism, 129°E to 140°E: Preliminary Results of the STORM Cruise

NASA Astrophysics Data System (ADS)

Maia, M.; Briais, A.; Barrere, F.; Boulart, C.; Ceuleneer, G.; Ferreira, N.; Hanan, B. B.; Hemond, C.; MacLeod, S.; Maillard, A. L.; Merkuryev, S. A.; Park, S. H.; Revillon, S.; Ruellan, E.; Schohn, A.; Watson, S. J.; Yang, Y. S.

2015-12-01

We present observations of the South-East Indian Ridge (SEIR) collected during the STORM cruise (South Tasmania Ocean Ridge and Mantle) on the N/O L'Atalante early 2015. The SEIR between Australia and Antarctica displays large variations of axial morphology despite an almost constant intermediate spreading rate. The Australia-Antarctic Discordance (AAD) between 120°E and 128°E is a section of the mid-ocean ridge where the magma budget is abnormally low, and which marks the boundary between Indian and Pacific mantle domains with distinct geochemical isotopic compositions. The STORM project focuses on the area east of the discordance from 128 to 140°E, where gravity highs observed on satellite-derived maps of the flanks of the SEIR reveal numerous volcanic seamounts. A major objective of the STORM cruise was to test the hypothesis of a mantle flow from the Pacific to the Indian domains. We collected multibeam bathymetry and magnetic data between 136 and 138°E to map off-axis volcanic ridges up to 10 Ma-old crust. We mapped the SEIR axis between 129 and 140°E, and the northern part of the George V transform fault. We collected rock samples on seamounts and in the transform fault, basaltic glass samples along the ridge axis, and near-bottom samples and in-situ measurements in the water column. Our observations reveal that the off-axis seamounts form near the SEIR axis, and are not associated to off-axis deformation of the ocean floor. They show a general shallowing of the ridge axis from the AAD to the George V TF and the presence of robust axial segments near the transform fault. They allow us to describe the complex evolution of the transform fault system. They also permit to locate new hydrothermal systems along the ridge axis. STORM cruise scientific party: F. Barrere, C. Boulart, G. Ceuleneer, N. Ferreira, B. Hanan, C. Hémond, S. Macleod, M. Maia, A. Maillard, S. Merkuryev, S.H. Park, S. Révillon, E. Ruellan, A. Schohn, S. Watson, and Y.S. Yang.

Hypothalamic-pituitary-adrenal axis response to acute psychosocial stress: Effects of biological sex and circulating sex hormones.

PubMed

Stephens, Mary Ann C; Mahon, Pamela B; McCaul, Mary E; Wand, Gary S

2016-04-01

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis influences the risk for developing stress-related disorders. Sex-dependent differences in the HPA axis stress response are believed to contribute to the different prevalence rates of stress-related disorders found in men and women. However, studies examining the HPA axis stress response have shown mixed support for sex differences, and the role of endogenous sex hormones on HPA axis response has not been adequately examined in humans. This study utilized the largest sample size to date to analyze the effects of biological sex and sex hormones on HPA axis social stress responses. Healthy, 18- to 30- year-old community volunteers (N=282) completed the Trier Social Stress Test (TSST), a widely used and well-validated stress-induction laboratory procedure. All women (n=135) were tested during the follicular phase of their menstrual cycle (when progesterone levels are most similar to men). Adrenocorticotropic hormone (ACTH) and cortisol measures were collected at multiple points throughout pre- and post-TSST. Testosterone and progesterone (in men) and progesterone and estradiol (in women) were determined pre-TSST. Following the TSST, men had greater ACTH and cortisol levels than women. Men had steeper baseline-to-peak and peak-to-end ACTH and cortisol response slopes than women; there was a trend for more cortisol responders among men than women. Testosterone negatively correlated with salivary cortisol response in men, while progesterone negatively correlated with ACTH and cortisol responses in women. These data confirm that men show more robust activation of the HPA axis response to the TSST than do women in the follicular phase of the menstrual cycle. Testosterone results suggest an inhibitory effect on HPA axis reactivity in men. Progesterone results suggest an inhibitory effect on HPA axis reactivity in women. Future work is needed to explain why men mount a greater ACTH and cortisol response to the TSST than do women during the follicular phase of the menstrual cycle. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dynamics of a spherical tippe top

NASA Astrophysics Data System (ADS)

Cross, Rod

2018-05-01

Experimental and theoretical results are presented concerning the inversion of a spherical tippe top. It was found that the top rises quickly while it is sliding and then more slowly when it starts rolling, in a manner similar to that observed previously with a spinning egg. As the top rises it rotates about the horizontal Y axis, an effect that is closely analogous to rotation of the top about the vertical Z axis. Both effects can be described in terms of precession about the respective axes. Steady precession about the Z axis arises from the normal reaction force in the Z direction, while precession about the Y axis arises from the friction force in the Y direction.

Three-dimensional optic axis determination using variable-incidence-angle polarization-optical coherence tomography

NASA Astrophysics Data System (ADS)

Ugryumova, Nadezhda; Gangnus, Sergei V.; Matcher, Stephen J.

2006-08-01

Polarization optical coherence tomography (PSOCT) is a powerful technique to nondestructively map the retardance and fast-axis orientation of birefringent biological tissues. Previous studies have concentrated on the case where the optic axis lies on the plane of the surface. We describe a method to determine the polar angle of the optic axis of a uniaxial birefringent tissue by making PSOCT measurements with a number of incident illumination directions. The method is validated on equine flexor tendon, yielding a variability of 4% for the true birefringence and 3% for the polar angle. We use the method to map the polar angle of fibers in the transitional region of equine cartilage.

Methods of fabricating a conductor assembly having a curvilinear arcuate shape

DOEpatents

Meinke, Rainer [Melbourne, FL

2011-08-23

A method for manufacture of a conductor assembly along a curvilinear axis. The assembly may be of the type which, when conducting current, generates a magnetic field or in which, in the presence of a changing magnetic field, a voltage is induced. In one example, the assembly includes a structure having a curved shape extending along the axis. A surface of the structure is positioned for formation of a channel along the curved shape. The structure is rotated about a second axis. While rotating the structure, a channel is formed in the surface that results in a helical shape in the structure. The channel extends both around and along the first axis.

Two-point motional Stark effect diagnostic for Madison Symmetric Torus

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

Ko, J.; Den Hartog, D. J.; Caspary, K. J.

2010-10-15

A high-precision spectral motional Stark effect (MSE) diagnostic provides internal magnetic field measurements for Madison Symmetric Torus (MST) plasmas. Currently, MST uses two spatial views - on the magnetic axis and on the midminor (off-axis) radius, the latter added recently. A new analysis scheme has been developed to infer both the pitch angle and the magnitude of the magnetic field from MSE spectra. Systematic errors are reduced by using atomic data from atomic data and analysis structure in the fit. Reconstructed current density and safety factor profiles are more strongly and globally constrained with the addition of the off-axis radiusmore » measurement than with the on-axis one only.« less

Preliminary characterization of a one-axis acoustic system. [acoustic levitation for space processing

NASA Technical Reports Server (NTRS)

Oran, W. A.; Reiss, D. A.; Berge, L. H.; Parker, H. W.

1979-01-01

The acoustic fields and levitation forces produced along the axis of a single-axis resonance system were measured. The system consisted of a St. Clair generator and a planar reflector. The levitation force was measured for bodies of various sizes and geometries (i.e., spheres, cylinders, and discs). The force was found to be roughly proportional to the volume of the body until the characteristic body radius reaches approximately 2/k (k = wave number). The acoustic pressures along the axis were modeled using Huygens principle and a method of imaging to approximate multiple reflections. The modeled pressures were found to be in reasonable agreement with those measured with a calibrated microphone.

The Numerical Calculation and Experimental Measurement of the Inductance Parameters for Permanent Magnet Synchronous Motor in Electric Vehicle

NASA Astrophysics Data System (ADS)

Jiang, Chao; Qiao, Mingzhong; Zhu, Peng

2017-12-01

A permanent magnet synchronous motor with radial magnetic circuit and built-in permanent magnet is designed for the electric vehicle. Finite element numerical calculation and experimental measurement are adopted to obtain the direct axis and quadrature axis inductance parameters of the motor which are vital important for the motor control. The calculation method is simple, the measuring principle is clear, the results of numerical calculation and experimental measurement are mutual confirmation. A quick and effective method is provided to obtain the direct axis and quadrature axis inductance parameters of the motor, and then improve the design of motor or adjust the control parameters of the motor controller.

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.

Chalcogenide molded freeform optics for mid-infrared lasers

NASA Astrophysics Data System (ADS)

Chenard, Francois; Alvarez, Oseas; Yi, Allen

2017-05-01

High-precision chalcogenide molded micro-lenses were produced to collimate mid-infrared Quantum Cascade Lasers (QCLs). Molded cylindrical micro-lens prototypes with aspheric contour (acylindrical), high numerical aperture (NA 0.8) and small focal length (f<2 mm) were fabricated to collimate the QCL fast-axis beam. Another innovative freeform micro-lens has an input acylindrical surface to collimate the fast axis and an orthogonal output acylindrical surface to collimate the slow axis. The thickness of the freeform lens is such that the output fast- and slow-axis beams are circular. This paper presents results on the chalcogenide molded freeform micro-lens designed to collimate and circularize QCL at 4.6 microns.

Horizontal EDNA miner

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

Justice, J.C.; Delli-Gatti, F.A.

1985-12-03

A mining machine is utilized for making original generally horizontal bores in coal seams, and for enlarging preexisting bores. A single cutting head is mounted for rotation about a first horizontal axis generally perpendicular to the dimension of elongation of the horizontal bore, and is pivotal about a second horizontal axis, parallel to the first axis, to change its cutting, vertical position within the bore. A non-rotatable body member, with side wall supports, is mounted posteriorly of the cutting head, and includes a conveyor mechanism and a power mechanism operatively connected to it. The machine can be sumped into amore » bore and then the cutting head rotated about the second axis to change the vertical position thereof, and then moved rearwardly, any cut material being continuously conveyed to the bore mouth by the conveyor mechanism. The amount of vertical movement during the pivoting action about the second axis is controlled in response to the automatic sensing of the thickness of the coal seam in which the machine operates.« less

The infrared bands Pechan prism axis parallel detection method

NASA Astrophysics Data System (ADS)

Qiang, Hua; Ji, Ming; He, Yu-lan; Wang, Nan-xi; Chang, Wei-jun; Wang, Ling; Liu, Li

2017-02-01

In this paper, we put forward a new method to adjust the air gap of the total reflection air gap of the infrared Pechan prism. The adjustment of the air gap in the air gap of the Pechan prism directly affects the parallelism of the optical axis, so as to affect the consistency of the optical axis of the infrared system. The method solves the contradiction between the total reflection and the high transmission of the infrared wave band, and promotes the engineering of the infrared wave band. This paper puts forward the method of adjusting and controlling, which can ensure the full reflection and high penetration of the light, and also can accurately measure the optical axis of the optical axis of the different Pechan prism, and can achieve the precision of the level of the sec. For Pechan prism used in the infrared band image de rotation, make the product to realize miniaturization, lightweight plays an important significance.

In-flight calibration of the spin axis offset of a fluxgate magnetometer with an electron drift instrument

NASA Astrophysics Data System (ADS)

Leinweber, H. K.; Russell, C. T.; Torkar, K.

2012-10-01

We show that the spin axis offset of a fluxgate magnetometer can be calibrated with an electron drift instrument (EDI) and that the required input time interval is relatively short. For missions such as Cluster or the upcoming Magnetospheric Multiscale (MMS) mission the spin axis offset of a fluxgate magnetometer could be determined on an orbital basis. An improvement of existing methods for finding spin axis offsets via comparison of accurate measurements of the field magnitude is presented, that additionally matches the gains of the two instruments that are being compared. The technique has been applied to EDI data from the Cluster Active Archive and fluxgate magnetometer data processed with calibration files also from the Cluster Active Archive. The method could prove to be valuable for the MMS mission because the four MMS spacecraft will only be inside the interplanetary field (where spin axis offsets can be calculated from Alfvénic fluctuations) for short periods of time and during unusual solar wind conditions.

Photographic simulation of off-axis blurring due to chromatic aberration in spectacle lenses.

PubMed

Doroslovački, Pavle; Guyton, David L

2015-02-01

Spectacle lens materials of high refractive index (nd) tend to have high chromatic dispersion (low Abbé number [V]), which may contribute to visual blurring with oblique viewing. A patient who noted off-axis blurring with new high-refractive-index spectacle lenses prompted us to do a photographic simulation of the off-axis aberrations in 3 readily available spectacle lens materials, CR-39 (nd = 1.50), polyurethane (nd = 1.60), and polycarbonate (nd = 1.59). Both chromatic and monochromatic aberrations were found to cause off-axis image degradation. Chromatic aberration was more prominent in the higher-index materials (especially polycarbonate), whereas the lower-index CR-39 had more astigmatism of oblique incidence. It is important to consider off-axis aberrations when a patient complains of otherwise unexplained blurred vision with a new pair of spectacle lenses, especially given the increasing promotion of high-refractive-index materials with high chromatic dispersion. Copyright © 2015 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Assessment of personality functioning: validity of the operationalized psychodynamic diagnosis axis IV (structure).

PubMed

Doering, Stephan; Burgmer, Markus; Heuft, Gereon; Menke, Dina; Bäumer, Brigitta; Lübking, Margit; Feldmann, Marcus; Schneider, Gudrun

2014-01-01

The assessment of personality functioning has recently become a focus of psychiatric diagnostics. The interview-based Operationalized Psychodynamic Diagnosis (OPD-2) provides a 'structure axis' for the assessment of personality functioning. One hundred twenty-four psychiatric patients were diagnosed by means of the Structured Clinical Interviews for DSM-IV (SCID-I and SCID-II), underwent OPD-2 interviews, and completed 9 questionnaires. The OPD-2 structure axis shows good interrater reliability (intraclass correlation = 0.793). Correlations between the OPD-2 structure axis domains and a priori selected questionnaire scales were of medium size and significant. Patients with a personality disorder (PD) showed significantly worse personality functioning than those without. In cluster B PD, personality functioning was more severely impaired than in cluster C PD. The OPD-2 structure axis shows good reliability as well as concurrent and discriminant validity and can be recommended for clinical use and research purposes. © 2013 S. Karger AG, Basel.

Multi-Axis Thrust Measurements of the EO-1 Pulsed Plasma Thruster

NASA Technical Reports Server (NTRS)

Arrington, Lynn A.; Haag, Thomas W.

1999-01-01

Pulsed plasma thrusters are low thrust propulsive devices which have a high specific impulse at low power. A pulsed plasma thruster is currently scheduled to fly as an experiment on NASA's Earth Observing-1 satellite mission. The pulsed plasma thruster will be used to replace one of the reaction wheels. As part of the qualification testing of the thruster it is necessary to determine the nominal thrust as a function of charge energy. These data will be used to determine control algorithms. Testing was first completed on a breadboard pulsed plasma thruster to determine nominal or primary axis thrust and associated propellant mass consumption as a function of energy and then later to determine if any significant off-axis thrust component existed. On conclusion that there was a significant off-axis thrust component with the bread-board in the direction of the anode electrode, the test matrix was expanded on the flight hardware to include thrust measurements along all three orthogonal axes. Similar off-axis components were found with the flight unit.

VizieR Online Data Catalog: SMART97, rigid Earth rotation new solution (Bretagnon+ 1998)

NASA Astrophysics Data System (ADS)

Bretagnon, P.; Francou, G.; Rocher, P.; Simon, J. L.

1998-03-01

The Earth rotation solution SMART97 (Solution du Mouvement de l'Axe de Rotation de la Terre) is an analytical solution of the Earth rotation in the rigid case. It gives the expressions of precession-nutation and rotation of the Earth for the 3 Euler angles ψ, ω, φ as well as for the quantities p, ɛ, χ, and the sidereal time. For the axis of figure (fig), these 7 quantities are given in the dynamical system (dyn) and in the kinematical system (kin). SMART97 also gives the variables ψ and ω, in the dynamical system, for the differences (axis of figure - axis of rotation) (rot) and (axis of figure - axis of the angular momentum) (ang). The accuracy of the solution is better than 2.2 microarcseconds for all these variables over 20000 days, between 1968 and 2023. A program EXAMPLE (Fortran 77) is provided which makes use of the subroutine SMART97 which substitutes the time in the series of the solutions SMART97. (18 data files).

A high bandwidth three-axis out-of-plane motion measurement system based on optical beam deflection

NASA Astrophysics Data System (ADS)

Piyush, P.; Giridhar, M. S.; Jayanth, G. R.

2018-03-01

Multi-axis measurement of motion is indispensable for characterization of dynamic systems and control of motion stages. This paper presents an optical beam deflection-based measurement system to simultaneously measure three-axis out-of-plane motion of both micro- and macro-scale targets. Novel strategies are proposed to calibrate the sensitivities of the measurement system. Subsequently the measurement system is experimentally realized and calibrated. The system is employed to characterize coupled linear and angular motion of a piezo-actuated stage. The measured motion is shown to be in agreement with theoretical expectation. Next, the high bandwidth of the measurement system has been showcased by utilizing it to measure coupled two-axis transient motion of a Radio Frequency Micro-Electro-Mechanical System switch with a rise time of about 60 μs. Finally, the ability of the system to measure out-of-plane angular motion about the second axis has been demonstrated by measuring the deformation of a micro-cantilever beam.

The role of sex and autonomy-connectedness in internalizing and externalizing personality pathology, coping and axis-I pathology: among psychiatric and healthy elderly.

PubMed

Bachrach, Nathan; Croon, Marcel; Bekker, Marrie

2017-06-01

In the current study we investigated the relationship of sex and autonomy-connectedness with internalizing and externalizing personality disorder symptoms (PDS), coping and axis-I pathology in older age. A path model was tested which was based on neo-analytical object relation, attachment- and primary-personality theory, among 100 clinical and 106 non-clinical elderly. In line with our model, autonomy-connectedness (self-awareness and capacity of managing new situations) was strongly associated to internalizing PDS in both groups. In both groups, neither sex nor autonomy-connectedness predicted externalizing PDS. Sex, internalizing as well as externalizing PDS and reactive defensive coping were associated to axis-I psychopathology. We conclude that sex and autonomy-connectedness were, similarly as in adult populations, associated to internalizing PDS and axis-I pathology. Treatment of elderly with internalizing PDS and axis-I psychopathology should therefore focus on enhancing autonomy-connectedness.

Highly c-axis-oriented monocrystalline Pb(Zr, Ti)O₃ thin films on si wafer prepared by fast cooling immediately after sputter deposition.

PubMed

Yoshida, Shinya; Hanzawa, Hiroaki; Wasa, Kiyotaka; Esashi, Masayoshi; Tanaka, Shuji

2014-09-01

We successfully developed sputter deposition technology to obtain a highly c-axis-oriented monocrystalline Pb(Zr, Ti)O3 (PZT) thin film on a Si wafer by fast cooling (~-180°C/min) of the substrate after deposition. The c-axis orientation ratio of a fast-cooled film was about 90%, whereas that of a slow-cooled (~-40°C/min) film was only 10%. The c-axis-oriented monocrystalline Pb(Zr0.5, Ti0.5)O3 films showed reasonably large piezoelectric coefficients, e(31,f) = ~-11 C/m(2), with remarkably small dielectric constants, ϵ(r) = ~220. As a result, an excellent figure of merit (FOM) was obtained for piezoelectric microelectromechanical systems (MEMS) such as a piezoelectric gyroscope. This c-axis orientation technology on Si will extend industrial applications of PZT-based thin films and contribute further to the development of piezoelectric MEMS.

FORGE Milford Triaxial Test Data and Summary from EGI labs

DOE Data Explorer

Joe Moore

2016-03-01

Six samples were evaluated in unconfined and triaxial compression, their data are included in separate excel spreadsheets, and summarized in the word document. Three samples were plugged along the axis of the core (presumed to be nominally vertical) and three samples were plugged perpendicular to the axis of the core. A designation of "V"indicates vertical or the long axis of the plugged sample is aligned with the axis of the core. Similarly, "H" indicates a sample that is nominally horizontal and cut orthogonal to the axis of the core. Stress-strain curves were made before and after the testing, and are included in the word doc.. The confining pressure for this test was 2800 psi. A series of tests are being carried out on to define a failure envelope, to provide representative hydraulic fracture design parameters and for future geomechanical assessments. The samples are from well 52-21, which reaches a maximum depth of 3581 ft +/- 2 ft into a gneiss complex.

Mechanical Strain Determines Cilia Length, Motility, and Planar Position in the Left-Right Organizer.

PubMed

Chien, Yuan-Hung; Srinivasan, Shyam; Keller, Ray; Kintner, Chris

2018-05-07

The Xenopus left-right organizer (LRO) breaks symmetry along the left-right axis of the early embryo by producing and sensing directed ciliary flow as a patterning cue. To carry out this process, the LRO contains different ciliated cell types that vary in cilia length, whether they are motile or sensory, and how they position their cilia along the anterior-posterior (A-P) planar axis. Here, we show that these different cilia features are specified in the prospective LRO during gastrulation, based on anisotropic mechanical strain that is oriented along the A-P axis, and graded in levels along the medial-lateral axis. Strain instructs ciliated cell differentiation by acting on a mesodermal prepattern present at blastula stages, involving foxj1. We propose that differential strain is a graded, developmental cue, linking the establishment of an A-P planar axis to cilia length, motility, and planar location during formation of the Xenopus LRO. Copyright © 2018 Elsevier Inc. All rights reserved.

Trapping of diffusing particles by striped cylindrical surfaces. Boundary homogenization approach

PubMed Central

Dagdug, Leonardo; Berezhkovskii, Alexander M.; Skvortsov, Alexei T.

2015-01-01

We study trapping of diffusing particles by a cylindrical surface formed by rolling a flat surface, containing alternating absorbing and reflecting stripes, into a tube. For an arbitrary stripe orientation with respect to the tube axis, this problem is intractable analytically because it requires dealing with non-uniform boundary conditions. To bypass this difficulty, we use a boundary homogenization approach which replaces non-uniform boundary conditions on the tube wall by an effective uniform partially absorbing boundary condition with properly chosen effective trapping rate. We demonstrate that the exact solution for the effective trapping rate, known for a flat, striped surface, works very well when this surface is rolled into a cylindrical tube. This is shown for both internal and external problems, where the particles diffuse inside and outside the striped tube, at three orientations of the stripe direction with respect to the tube axis: (a) perpendicular to the axis, (b) parallel to the axis, and (c) at the angle of π/4 to the axis. PMID:26093574

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.

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.

Effect of grain orientation and coating on thermal fatigue resistance of a directionally solidified superalloy (MAR-M 247)

NASA Technical Reports Server (NTRS)

Bizon, P. T.; Dreshfield, R. L.; Calfo, F. D.

1979-01-01

The effect of off-axis directionally solidified (DS) grain growth on thermal fatigue life of Mar-M 247 alloy was evaluated. Uncoated conventionally cast as well as DS wedge bars were cycled in a burner rig between 1070 C and room temperature. The longitudinal axis and leading edge of the specimen coincided. As the angle between the specimen longitudinal axis and growth axis increased, the thermal fatigue life decreased for both the uncoated and aluminide-coated bars. Life increases of about 50 cycles for the DS conditions were attributed to coating. The decrease in thermal fatigue life with increasing angle is primarily attributed to the increase in modulus of elasticity with increasing angle and not to the intersection of DS grain boundaries with the specimen leading edge. The thermal fatigue cracks were observed to be transgranular in the DS material. Limited tensile and stress-rupture properties of conventionally cast and off-axis DS Mar-M 247 alloy are also presented.

The Kerala Decentration Meter. A new method and devise for fitting the optical of spectacle lenses in the visual axis.

PubMed

Joseph, T K; Kartha, C P

1982-01-01

Centring of spectacle lenses is much neglected field of ophthalmology. The prismatic effect caused by wrong centring results in a phoria on the eye muscles which in turn causes persistent eyestrain. The theory of visual axis, optical axis and angle alpha is discussed. Using new methods the visual axis and optical axis of 35 subjects were measured. The results were computed for facial asymmetry, parallax error, angle alpha and also decentration for near vision. The results show that decentration is required on account of each of these factors. Considerable correction is needed in the vertical direction, a fact much neglected nowadays; and vertical decentration results in vertical phoria which is more symptomatic than horizontal phorias. Angle Alpha was computed for each of these patients. A new devise called 'The Kerala Decentration Meter' using the pinhole method for measuring the degree of decentration from the datum centre of the frame, and capable of correcting all the factors described above, is shown with diagrams.

The vibration discomfort of standing people: evaluation of multi-axis vibration.

PubMed

Thuong, Olivier; Griffin, Michael J

2015-01-01

Few studies have investigated discomfort caused by multi-axis vibration and none has explored methods of predicting the discomfort of standing people from simultaneous fore-and-aft, lateral and vertical vibration of a floor. Using the method of magnitude estimation, 16 subjects estimated their discomfort caused by dual-axis and tri-axial motions (octave-bands centred on either 1 or 4 Hz with various magnitudes in the fore-and-aft, lateral and vertical directions) and the discomfort caused by single-axis motions. The method of predicting discomfort assumed in current standards (square-root of the sums of squares of the three components weighted according to their individual contributions to discomfort) provided reasonable predictions of the discomfort caused by multi-axis vibration. Improved predictions can be obtained for specific stimuli, but no single simple method will provide accurate predictions for all stimuli because the rate of growth of discomfort with increasing magnitude of vibration depends on the frequency and direction of vibration.

Magnetic properties and effect of pressure on the electronic state of EuCo2Ge2

NASA Astrophysics Data System (ADS)

Ashitomi, Y.; Kakihana, M.; Honda, F.; Nakamura, A.; Aoki, D.; Uwatoko, Y.; Nakashima, M.; Amako, Y.; Takeuchi, T.; Kida, T.; Tahara, T.; Hagiwara, M.; Haga, Y.; Hedo, M.; Nakama, T.; Ōnuki, Y.

2018-05-01

EuCo2Ge2 with the tetragonal structure is a Eu-divalent antiferromagnet with the Néel temperature TN = 23 K. The magnetic easy-axis corresponds to the [100] direction (a-axis), while the [001] direction (c-axis) is a hard-axis. The magnetization for H∥ [ 100 ] indicates a metamagnetic transition at 25 kOe and saturates above 75 kOe. On the other hand, the hard-axis magnetization increases approximately linearly and saturates above 110 kOe. The magnetic phase diagram was constructed. A characteristic feature in EuCo2Ge2 is known as a valence transition under pressure, from Eu 2+δ to Eu 3 - δ ‧(δ, δ ‧ < 1). We also clarified the valence transition by measuring the electrical resistivity under pressure. The valence transition occurs at 3 GPa, with a hysteresis, and terminates at about 4.5 GPa. Further increasing pressure, the electronic state is changed into a moderate heavy fermion state and approaches the nearly trivalent electronic state.

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.

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.

Pathophysiology of the Effects of Alcohol Abuse on the Endocrine System.

PubMed

Rachdaoui, Nadia; Sarkar, Dipak K

2017-01-01

Alcohol can permeate virtually every organ and tissue in the body, resulting in tissue injury and organ dysfunction. Considerable evidence indicates that alcohol abuse results in clinical abnormalities of one of the body's most important systems, the endocrine system. This system ensures proper communication between various organs, also interfacing with the immune and nervous systems, and is essential for maintaining a constant internal environment. The endocrine system includes the hypothalamic-pituitary-adrenal axis, the hypothalamic-pituitary-gonadal axis, the hypothalamic-pituitary-thyroid axis, the hypothalamic-pituitary-growth hormone/insulin-like growth factor-1 axis, and the hypothalamic-posterior pituitary axis, as well as other sources of hormones, such as the endocrine pancreas and endocrine adipose tissue. Alcohol abuse disrupts all of these systems and causes hormonal disturbances that may result in various disorders, such as stress intolerance, reproductive dysfunction, thyroid problems, immune abnormalities, and psychological and behavioral disorders. Studies in both humans and animal models have helped shed light on alcohol's effects on various components of the endocrine system and their consequences.

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.

Expected neutrino fluence from short Gamma-Ray Burst 170817A and off-axis angle constraints

NASA Astrophysics Data System (ADS)

Biehl, D.; Heinze, J.; Winter, W.

2018-05-01

We compute the expected neutrino fluence from SGRB 170817A, associated with the gravitational wave event GW 170817, directly based on Fermi observations in two scenarios: structured jet and off-axis (observed) top-hat jet. While the expected neutrino fluence for the structured jet case is very small, large off-axis angles imply high radiation densities in the jet, which can enhance the neutrino production efficiency. In the most optimistic allowed scenario, the neutrino fluence can reach only 10-4 of the sensitivity of the neutrino telescopes. We furthermore demonstrate that the fact that gamma-rays can escape limits the baryonic loading (energy in protons versus photons) and the off-axis angle for the internal shock scenario. In particular, for a baryonic loading of 10, the off-axis angle is more strongly constrained by the baryonic loading than by the time delay between the gravitational wave event and the onset of the gamma-ray emission.

Asymmetric Thrust Reversers

NASA Technical Reports Server (NTRS)

Chandler, Jesse M. (Inventor); Suciu, Gabriel L. (Inventor)

2018-01-01

An aircraft includes a propulsion supported within an aft portion of a fuselage A thrust reverser is mounted in the aft portion of the fuselage proximate the propulsion system for directing thrust in a direction to slow the aircraft. The thrust reverser includes an upper blocker door movable about a first pivot axis to a deployed position and a lower blocker door movable about a second pivot axis not parallel to the first pivot axis.

Results of a utility survey of the status of large wind turbine development

NASA Technical Reports Server (NTRS)

Watts, A.; Quraeshi, S.; Rowley, L. P.

1979-01-01

Wind energy conversion systems were surveyed from a utility viewpoint to establish the state of the art with regard to: (1) availability of the type of machines; (2) quality of power generation; (3) suitability for electrical grid; (4) reliability; and (5) economics. Of the 23 designs discussed, 7 have vertical axis wind turbines, 9 have upwind horizontal axis turbines, and 7 have downwind horizontal axis turbines.

SCATHA-Analysis System

DTIC Science & Technology

1981-01-31

geometric factor. For the low energy FSA detectors, the background counts must be subtracted from the measured (actual) counts before the geometric factor...and high energy) each provide a background measure - ment. The background counts for the low energy ESA (LE ESA) were subtracted from the other four LE...perpendicular to the spacecraft +X reference spin axis and 189.660 around from the +Z axis (with this angle measured from the +Z axis in the direction

Ride quality meter

NASA Technical Reports Server (NTRS)

Leatherwood, J. D.; Dempsey, T. K.; Clevenson, S. A.; Stephens, D. G. (Inventor)

1983-01-01

A ride quality meter is disclosed that automatically transforms vibration and noise measurements into a single number index of passenger discomfort. The noise measurements are converted into a noise discomfort value. The vibrations are converted into single axis discomfort values which are then converted into a combined axis discomfort value. The combined axis discomfort value is corrected for time duration and then summed with the noise discomfort value to obtain a total discomfort value.

Method of Characteristic (MOC) Nozzle Flowfield Solver - User’s Guide and Input Manual

DTIC Science & Technology

2013-01-01

Description: Axi or Planar calculation. Value Description Default 0.0 Planer solution 1.0 Axisymmetric solution * &INPUT: NI Date Type: Integer...angle error !... !... Set Control values !... DELTA = 1.0 !1 axi, 0 planer (Mass flux not working correctly) NI = 81...DELTA = 1.0 !1 axi, 0 planer NI = 71 !NUMBER OF RADIAL POINTS ON INFLOW PLANE (Max 99) NT = 35 !NUMBER OF

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.

Fast steering and quick positioning of large field-of-regard, two-axis, four-gimbaled sight

NASA Astrophysics Data System (ADS)

Ansari, Zahir Ahmed; Nigam, Madhav Ji; Kumar, Avnish

2017-07-01

Fast steering and quick positioning are prime requirements of the current electro-optical tracking system to achieve quick target acquisition. A scheme has been proposed for realizing these features using two-axis, four-gimbaled sight. For steering the line of sight in the stabilization mode, outer gimbal is slaved to the gyro stabilized inner gimbal. Typically, the inner gimbals have direct drives and outer gimbals have geared drives, which result in a mismatch in the acceleration capability of their servo loops. This limits the allowable control bandwidth for the inner gimbal. However, to achieve high stabilization accuracy, high bandwidth control loops are essential. This contradictory requirement has been addressed by designing a suitable command conditioning module for the inner gimbals. Also, large line-of-sight freedom in pitch axis is required to provide a wide area surveillance capacity for airborne application. This leads to a loss of freedom along the yaw axis as the pitch angle goes beyond 70 deg or so. This is addressed by making the outer gimbal master after certain pitch angle. Moreover, a mounting scheme for gyro has been proposed to accomplish yaw axis stabilization for 110-deg pitch angle movement with a single two-axis gyro.

Tiperon

NASA Technical Reports Server (NTRS)

Lewis, Carl E. (Inventor); Carlton, Lindley A. (Inventor); Saeks, Richard E. (Inventor)

2004-01-01

A control surface for an air vehicle (e.g., an aircraft, rocket, or missile) is useful for flight control at both subsonic and supersonic speeds. The control surface defines the outboardmost tip of a flight structure (e.g., a wing, tail or other stabilizer) of the air vehicle. Hence, the control surface is referred to as a `tiperon`. The tiperon has an approximately L-shaped configuration, and can be rotated relative to a fixed portion of the flight structure about a control axis. The respective surface areas of the tiperon sections forward and aft of the control axis are proportioned to place the subsonic center of pressure aft of the control axis to enhance aircraft control, and preferably also forward of the centroid of tiperon surface area. Also, the control surface sections forward and aft of the control axis are preferably mass-balanced, or at least nearly so, to enhance aircraft control at supersonic speeds. Either of the tiperon sections forward and aft of the control axis can be tapered to reduce the dependence of the moment exerted by air flow about the control axis, upon the tiperon's angle-of-attack. The tiperon also has enough surface area to control the air vehicle, even at low airspeeds. The invention is also directed to air vehicles incorporating one or more such control surfaces.

Neoclassical toroidal plasma viscosity in the vicinity of the magnetic axis in tokamaks with broken symmetry

NASA Astrophysics Data System (ADS)

Shaing, K. C.; Lee, H.; Seol, J.; Aydemir, A. Y.

2015-08-01

Theory for neoclassical toroidal plasma viscosity in the low collisionality regime is extended to the vicinity of the magnetic axis in tokamaks with broken symmetry. The toroidal viscosity is induced by particles drifting off the perturbed magnetic surface under the influence of the symmetry breaking magnetic field. In the region away from the magnetic axis, the drift orbit dynamics is governed by the bounce averaged drift kinetic equation in the low collisionality regimes. In the vicinity of the magnetic axis, it is the drift kinetic equation, averaged over the trapped particle orbits, i.e., potato orbits, that governs the drift dynamics. The orbit averaged drift kinetic equation is derived when collision frequency is low enough for trapped particles to complete their potato trajectories. The resultant equation is solved in the 1 /ν regime to obtain transport fluxes and, thus, toroidal plasma viscosity through flux-force relation. Here, ν is the collision frequency. The viscosity does not vanish on the magnetic axis, and has the same scalings as that in the region away from magnetic axis, except that the fraction of bananas is replaced by the fraction of potatoes. It also has a weak radial dependence. Modeling of plasma flow velocity V for the case where the magnetic surfaces are broken is also discussed.

Results of the psychiatric, select-out evaluation of US astronaut applications

NASA Technical Reports Server (NTRS)

Faulk, D. M.; Santy, P. A.; Holland, A. W.; Marsh, R.

1992-01-01

The psychiatric exclusion criteria for astronauts are based on NASA Medical Psychiatric Standards for space flight. Until recently, there were no standardized methods to evaluate disqualifying psychopathology in astronaut applicants. Method: One hundred and six astronaut applicants who had passed the intitial screening were evaluated for Axis 1 and Axis 2 DSM-3-R diagnoses using the NASA structured psychiatric interview. The interview consisted of three parts: (1) an unstructured portion for obtaining biographical and historical information, (2) the schedule for effective disorders-lifetime version (SASDL), specially modified to include all disqualifying Axis 1 mental disorders; and, (3) the personality assessment schedule (PAS) also modified to evaluate for Axis 2 disorders. Results: Nine of 106 candidates (8.5 percent) met diagnostic criteria for six Axis 1 disorders (including V code) or Axis 2 disorders. Two of these disorders were disqualifying for the applicants. 'Near' diagnoses (where applicants met at least 50 percent of the listed criteria) were assessed to demonstrate that clinicians using the interview were able to overcome applicants' reluctance to report symptomatomatology. Conclusion: The use of the NASA structured interview was effective in identifying past and present psychopathology in a group of highly motivated astronaut applicants. This was the first time a structured psychiatric interview had been used in such a setting for this purpose.

An historical perspective on the pioneering experiments of John Saunders.

PubMed

Tickle, Cheryll

2017-09-15

John Saunders was a highly skilled embryologist who pioneered the study of limb development. His studies on chick embryos provided the fundamental framework for understanding how vertebrate limbs develop. This framework inspired generations of scientists and formed the bridge from experimental embryology to molecular mechanisms. Saunders investigated how feathers become organized into tracts in the skin of the chick wing and also identified regions of programmed cell death. He discovered that a region of thickened ectoderm that rims the chick wing bud - the apical ectodermal ridge - is required for outgrowth and the laying down of structures along the proximo-distal axis (long axis) of the wing, identified the zone of polarizing activity (ZPA; polarizing region) that controls development across the anteroposterior axis ("thumb to little finger "axis) and contributed to uncovering the importance of the ectoderm in development of structures along the dorso-ventral axis ( "back of hand to palm" axis). This review looks in depth at some of his original papers and traces how he made the crucial findings about how limbs develop, considering these findings both in the context of contemporary knowledge at the time and also in terms of their immediate impact on the field. Copyright © 2017 Elsevier Inc. All rights reserved.

Seismic anisotropy in the Earth's innermost inner core: Testing structural models against mineral physics predictions

DOE PAGES

Romanowicz, Barbara; Cao, Aimin; Godwal, Budhiram; ...

2016-01-06

Using an updated data set of ballistic PKIKP travel time data at antipodal distances, we test different models of anisotropy in the Earth's innermost inner core (IMIC) and obtain significantly better fits for a fast axis aligned with Earth's rotation axis, rather than a quasi-equatorial direction, as proposed recently. Reviewing recent results on the single crystal structure and elasticity of iron at core conditions, we find that an hcp structure with the fast c axis parallel to Earth's rotation is more likely but a body-centered cubic structure with the [111] axis aligned in that direction results in very similar predictionsmore » for seismic anisotropy. These models are therefore not distinguishable based on current seismological data. In addition, to match the seismological observations, the inferred strength of anisotropy in the IMIC (6–7%) implies almost perfect alignment of iron crystals, an intriguing, albeit unlikely situation, especially in the presence of heterogeneity, which calls for further studies. Fast axis of anisotropy in the central part of the inner core aligned with Earth's axis of rotation Lastly, the structure of iron in the inner core is most likely hcp, not bcc Not currently possible to distinguish between hcp and bcc structures from seismic observations« less

AXIS: an instrument for imaging Compton radiographs using the Advanced Radiography Capability on the NIF.

PubMed

Hall, G N; Izumi, N; Tommasini, R; Carpenter, A C; Palmer, N E; Zacharias, R; Felker, B; Holder, J P; Allen, F V; Bell, P M; Bradley, D; Montesanti, R; Landen, O L

2014-11-01

Compton radiography is an important diagnostic for Inertial Confinement Fusion (ICF), as it provides a means to measure the density and asymmetries of the DT fuel in an ICF capsule near the time of peak compression. The AXIS instrument (ARC (Advanced Radiography Capability) X-ray Imaging System) is a gated detector in development for the National Ignition Facility (NIF), and will initially be capable of recording two Compton radiographs during a single NIF shot. The principal reason for the development of AXIS is the requirement for significantly improved detection quantum efficiency (DQE) at high x-ray energies. AXIS will be the detector for Compton radiography driven by the ARC laser, which will be used to produce Bremsstrahlung X-ray backlighter sources over the range of 50 keV-200 keV for this purpose. It is expected that AXIS will be capable of recording these high-energy x-rays with a DQE several times greater than other X-ray cameras at NIF, as well as providing a much larger field of view of the imploded capsule. AXIS will therefore provide an image with larger signal-to-noise that will allow the density and distribution of the compressed DT fuel to be measured with significantly greater accuracy as ICF experiments are tuned for ignition.

Relationship Between Adverse Childhood Experiences and Homelessness and the Impact of Axis I and II Disorders

PubMed Central

Roos, Leslie E.; Mota, Natalie; Afifi, Tracie O.; Katz, Laurence Y.; Distasio, Jino

2013-01-01

Objectives. We investigated the links between homelessness associated with serious mental and physical healthy disparities and adverse childhood experiences (ACEs) in nationally representative data, with Axis I and II disorders as potential mediators. Methods. We examined data from the National Epidemiologic Survey of Alcohol and Related Conditions in 2001–2002 and 2004–2005, and included 34 653 participants representative of the noninstitutionalized US population who were 20 years old or older. We studied the variables related to 4 classes of Axis I disorders, all 10 Axis II personality disorders, a wide range of ACEs, and a lifetime history of homelessness. Results. Analyses revealed high prevalences of each ACE in individuals experiencing lifetime homelessness (17%–60%). A mediation model with Axis I and II disorders determined that childhood adversities were significantly related to homelessness through direct effects (adjusted odd ratios = 2.04, 4.24) and indirect effects, indicating partial mediation. Population attributable fractions were also reported. Conclusions. Although Axis I and II disorders partially mediated the relationship between ACEs and homelessness, a strong direct association remained. This novel finding has implications for interventions and policy. Additional research is needed to understand relevant causal pathways. PMID:24148049

HPA axis hyperactivity as suicide predictor in elderly mood disorder inpatients.

PubMed

Jokinen, Jussi; Nordström, Peter

2008-11-01

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis function is associated with suicidal behaviour and age-associated alterations in HPA axis functioning may render elderly individuals more susceptible to HPA dysregulation related to mood disorders. Research on HPA axis function in suicide prediction in elderly mood disorder patients is sparse. The study sample consisted of 99 depressed elderly inpatients 65 years of age or older admitted to the department of Psychiatry at the Karolinska University Hospital between 1980 and 2000. The hypothesis was that elderly mood disorder inpatients who fail to suppress cortisol in the dexamethasone suppression test (DST) are at higher risk of suicide. The DST non-suppression distinguished between suicides and survivors in elderly depressed inpatients and the suicide attempt at the index episode was a strong predictor for suicide. Additionally, the DST non-suppression showed higher specificity and predictive value in the suicide attempter group. Due to age-associated alterations in HPA axis functioning, the optimal cut-off for DST non-suppression in suicide prediction may be higher in elderly mood disorder inpatients. These data demonstrate the importance of attempted suicide and DST non-suppression as predictors of suicide risk in late-life depression and suggest the use for neuroendocrine testing of HPA axis functioning as a complementary tool in suicide prevention.

Personality disorders and associated features in cocaine-dependent inpatients.

PubMed

Kranzler, H R; Satel, S; Apter, A

1994-01-01

Previous research has shown a high prevalence of comorbid personality disorders among individuals seeking treatment for cocaine dependence. We studied axis II disorders (using the Structured Clinical Interview for DSM-III-R Personality Disorders [SCID-II]) in 50 patients admitted for inpatient rehabilitation. All patients met lifetime criteria for cocaine dependence and reported cocaine use during the month before admission. Seventy percent of patients met criteria for at least one axis II diagnosis; the mean number of axis II diagnoses among these patients was 2.54 (range, one to six). The most common axis II diagnosis was borderline (34% of all patients), followed by antisocial and narcissistic (each 28%), avoidant and paranoid (each 22%), obsessive-compulsive (16%), and dependent (10%). To evaluate the relationship between comorbid personality pathology, substance abuse, and other psychiatric symptomatology, patients were divided into two groups based on whether they received an axis II disorder diagnosis. The groups did not differ on substance abuse variables. However, there were significant group differences on a measure of psychosis proneness and in the number of comorbid depressive and anxiety disorder diagnoses. These results are consistent with other studies of personality disorders in substance abuse patients, and suggest that it may be clinically useful to characterize cocaine-dependent patients with respect to comorbid axis II disorders.

Extreme Right Axis Deviation in Acute Myocardial Infarction: A Hazardous Signal of Poor Prognosis.

PubMed

Wang, Qingyu; Pan, Shuo; Liu, Fuqiang; Yang, Dan; Wang, Jun-Kui

2018-05-11

BACKGROUND New-onset extreme right axis deviation and right bundle branch block (RBBB) are rare during acute myocardial infarction (AMI), and has only been reported in several cases reflecting the severity of AMI. It could predict severe clinical complications and higher risks in coronary artery disease. Although there is little electrophysiological explanation, the complications are severe. They should be emphasized in newly diagnosed extreme right axis deviation and RBBB in AMI. CASE REPORT A 72-year-old male was admitted to our department with a chief complaint of intermittent retrosternal chest pain and was diagnosed with extensive anterior myocardial infarction with RBBB, by elevated myocardial enzymes and ECG. The main wave direction of QRS in lead aVR was positive and showed an extreme right axis deviation. After a month, the patient's chest distress and the RBBB vanished, but a right axis deviation still existed. The echocardiogram showed prior extensive anterior myocardial infarction (including apex myocardia) and lower LVEF. CONCLUSIONS New diagnosed RBBB and right axis deviation is uncommon and could be a useful clue to evaluate myocardial ischemia in AMI cases. This electrocardiographic marker can identify coronary artery occlusion where ST-segments are hard to evaluate, and hence, patients may benefit most from early and complete revascularization strategies such as primary angioplasty.

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.

A Wavelet Bicoherence-Based Quadratic Nonlinearity Feature for Translational Axis Condition Monitoring

PubMed Central

Li, Yong; Wang, Xiufeng; Lin, Jing; Shi, Shengyu

2014-01-01

The translational axis is one of the most important subsystems in modern machine tools, as its degradation may result in the loss of the product qualification and lower the control precision. Condition-based maintenance (CBM) has been considered as one of the advanced maintenance schemes to achieve effective, reliable and cost-effective operation of machine systems, however, current vibration-based maintenance schemes cannot be employed directly in the translational axis system, due to its complex structure and the inefficiency of commonly used condition monitoring features. In this paper, a wavelet bicoherence-based quadratic nonlinearity feature is proposed for translational axis condition monitoring by using the torque signature of the drive servomotor. Firstly, the quadratic nonlinearity of the servomotor torque signature is discussed, and then, a biphase randomization wavelet bicoherence is introduced for its quadratic nonlinear detection. On this basis, a quadratic nonlinearity feature is proposed for condition monitoring of the translational axis. The properties of the proposed quadratic nonlinearity feature are investigated by simulations. Subsequently, this feature is applied to the real-world servomotor torque data collected from the X-axis on a high precision vertical machining centre. All the results show that the performance of the proposed feature is much better than that of original condition monitoring features. PMID:24473281

Two spinning ways for precession dynamo.

PubMed

Cappanera, L; Guermond, J-L; Léorat, J; Nore, C

2016-04-01

It is numerically demonstrated by means of a magnetohydrodynamic code that precession can trigger dynamo action in a cylindrical container. Fixing the angle between the spin and the precession axis to be 1/2π, two limit configurations of the spinning axis are explored: either the symmetry axis of the cylinder is parallel to the spin axis (this configuration is henceforth referred to as the axial spin case), or it is perpendicular to the spin axis (this configuration is referred to as the equatorial spin case). In both cases, the centro-symmetry of the flow breaks when the kinetic Reynolds number increases. Equatorial spinning is found to be more efficient in breaking the centro-symmetry of the flow. In both cases, the average flow in the reference frame of the mantle converges to a counter-rotation with respect to the spin axis as the Reynolds number grows. We find a scaling law for the average kinetic energy in term of the Reynolds number in the axial spin case. In the equatorial spin case, the unsteady asymmetric flow is shown to be capable of sustaining dynamo action in the linear and nonlinear regimes. The magnetic field is mainly dipolar in the equatorial spin case, while it is is mainly quadrupolar in the axial spin case.

Dietary Manipulations That Induce Ketosis Activate the HPA Axis in Male Rats and Mice: A Potential Role for Fibroblast Growth Factor-21.

PubMed

Ryan, Karen K; Packard, Amy E B; Larson, Karlton R; Stout, Jayna; Fourman, Sarah M; Thompson, Abigail M K; Ludwick, Kristen; Habegger, Kirk M; Stemmer, Kerstin; Itoh, Nobuyuki; Perez-Tilve, Diego; Tschöp, Matthias H; Seeley, Randy J; Ulrich-Lai, Yvonne M

2018-01-01

In response to an acute threat to homeostasis or well-being, the hypothalamic-pituitary-adrenocortical (HPA) axis is engaged. A major outcome of this HPA axis activation is the mobilization of stored energy, to fuel an appropriate behavioral and/or physiological response to the perceived threat. Importantly, the extent of HPA axis activity is thought to be modulated by an individual's nutritional environment. In this study, we report that nutritional manipulations signaling a relative depletion of dietary carbohydrates, thereby inducing nutritional ketosis, acutely and chronically activate the HPA axis. Male rats and mice maintained on a low-carbohydrate high-fat ketogenic diet (KD) exhibited canonical markers of chronic stress, including increased basal and stress-evoked plasma corticosterone, increased adrenal sensitivity to adrenocorticotropin hormone, increased stress-evoked c-Fos immunolabeling in the paraventricular nucleus of the hypothalamus, and thymic atrophy, an indicator of chronic glucocorticoid exposure. Moreover, acutely feeding medium-chain triglycerides (MCTs) to rapidly induce ketosis among chow-fed male rats and mice also acutely increased HPA axis activity. Lastly, and consistent with a growing literature that characterizes the hepatokine fibroblast growth factor-21 (FGF21) as both a marker of the ketotic state and as a key metabolic stress hormone, the HPA response to both KD and MCTs was significantly blunted among mice lacking FGF21. We conclude that dietary manipulations that induce ketosis lead to increased HPA axis tone, and that the hepatokine FGF21 may play an important role to facilitate this effect. Copyright © 2018 Endocrine Society.

HPA axis programming by maternal undernutrition in the male rat offspring.

PubMed

Vieau, Didier; Sebaai, Naima; Léonhardt, Marion; Dutriez-Casteloot, Isabelle; Molendi-Coste, Olivier; Laborie, Christine; Breton, Christophe; Deloof, Sylvie; Lesage, Jean

2007-08-01

Epidemiological and experimental studies have demonstrated that perinatal alterations such as maternal undernutrition are frequently associated with the onset of several chronic adult diseases. Although the physiological mechanisms involved in this "fetal programming" remain largely unknown, it has been shown that early exposure to undernutrition programs hypothalamic-pituitary-adrenal (HPA) axis throughout lifespan. However, the wide spectrum of experimental paradigms used (species, sex, age of the animals, and duration and severity of undernutrition exposure) has given rise to variable results that are difficult to interpret. To circumvent this problem, we used the same experimental protocol of maternal food restriction to study the effects of a severe maternal undernutrition on the HPA axis activity in the male rat offspring throughout the life, namely from fetal stage to adulthood. Mothers exposed to food restriction received 50% (FR50) of the daily intake of pregnant dams during the last week of gestation and lactation. In FR50 fetuses, HPA axis function was reduced and associated with a decreased placental 11beta-HSD2 activity and a greater transplacental transfer of glucocorticoids. At weaning, maternal food restriction reduced HPA axis activity in response to an ether inhalation stress. In young adults (4-month-old), only fine HPA axis alterations were observed, whereas in older ones (8-month-old), maternal undernutrition was associated with chronic hyperactivity of this neuroendocrine axis. Interestingly, excessive glucocorticoids production is observed in a growing number of pathologies such as metabolic, cognitive, immune and inflammatory diseases, suggesting that they could, at least in part, result from fetal undernutrition and thus have a neurodevelopmental origin.

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.

Left Axis Deviation in Children Without Previously Known Heart Disease.

PubMed

Schneider, Andrew E; Cannon, Bryan C; Johnson, Jonathan N; Ackerman, Michael J; Wackel, Philip L

2018-02-01

Left axis deviation (LAD) discovered in children via electrocardiogram (ECG) is uncommon but can be associated with heart disease (HD). The optimal diagnostic approach in a seemingly healthy child with LAD is unclear. We sought to better stratify which patients with LAD but without previously known HD may warrant additional workup. A retrospective chart review was performed to identify patients ≥1 to <18 years of age with LAD (QRS frontal plane axis 0 to -90) on an ECG between January 2002 and December 2014. Patients with known HD before their initial ECG were excluded. Overall, 296 patients were identified ( n = 181 [61%] male; mean age: 10.8 ± 4.6 years; mean QRS axis: -24 ± 22°). An echocardiogram was performed in 158 (53%) patients, with 24 (15%) having HD. Compared with those with an echocardiogram but without HD ( n = 134), patients with HD had a more negative mean QRS axis (-42 vs -27°; P = .002) and were more likely to have a QRS axis ≤-42° (58% vs 26%; P = .003), ECG chamber enlargement or hypertrophy (38% vs 5%; P < .0001), and abnormal cardiac physical examination findings (75% vs 8%; P < .0001). LAD discovered in isolation in the asymptomatic pediatric patient may not necessitate further cardiovascular investigation. Clinicians should consider obtaining an echocardiogram in patients with LAD and ECG cardiac chamber enlargement or hypertrophy, a QRS axis ≤-42°, and/or the presence of abnormal cardiac physical examination findings. Copyright © 2018 by the American Academy of Pediatrics.

Medulloblastoma--prognostic factors and outcome of treatment: Review of the Mayo Clinic experience

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

Garton, G.R.; Schomberg, P.J.; Scheithauer, B.W.

1990-08-01

From March 1965 through December 1984, 58 patients (35 male and 23 female patients; median age, 17 years) with posterior fossa (PF) medulloblastoma underwent surgical treatment and postoperative radiation therapy at our institution. Radiation fields were the craniospinal axis in 39 patients, PF plus spinal axis in 12, PF in 6, and whole brain in 1. Median radiation doses were 43 Gy (22 to 60 Gy) to the PF and 34 Gy (6.2 to 50 Gy) to the spinal axis. Overall 5- and 10-year survivals were 50% and 33%, respectively; 5- and 10-year relapse-free survivals were 46% and 32%. Treatmentmore » failed in 34 patients (59%): in 18 who had irradiation to the craniospinal axis (13 had received 50 Gy or less to the PF) and in 16 who had a radiation field of less than the craniospinal axis. A statistically significant (P less than 0.05) improvement in 10-year survival was associated with the following prognostic variables: PF dose of 50 Gy or more, whole-brain irradiation, and spinal axis irradiation. In comparison with subtotal resection, total resection was correlated with better 10-year relapse-free survival but not overall survival. All five patients with initial treatment failure only in the spine had received a radiation dose of 30 Gy or less to the spinal axis. The 2-year survival after relapse was 46% with salvage chemotherapy or irradiation in 23 patients and 0% in the 11 patients who received no further treatment (P less than 0.01).« less

Contribution of the maculo-ocular reflex to gaze stability in the rabbit.

PubMed

Pettorossi, V E; Errico, P; Santarelli, R M

1991-01-01

The contribution of the maculo-ocular reflex to gaze stability was studied in 10 pigmented rabbits by rolling the animals at various angles of sagittal inclination of the rotation and/or longitudinal animal axes. At low frequencies (0.005-0.01 Hz) of sinusoidal stimulation the vestibulo-ocular reflex (VOR) was due to macular activation, while at intermediate and high frequencies it was mainly due to ampullar activation. The following results were obtained: 1) maculo-ocular reflex gain decreased as a function of the cosine of the angle between the rotation axis and the earth's horizontal plane. No change in gain was observed when longitudinal animal axis alone was inclined. 2) At 0 degrees of rotation axis and with the animal's longitudinal axis inclination also set at 0 degrees, the maculo-ocular reflex was oriented about 20 degrees forward and upward with respect to the earth's vertical axis. This orientation remained constant with sagittal inclinations of the rotation and/or longitudinal animal axes ranging from approximately 5 degrees upward to 30 degrees downward. When the longitudinal animal axis was inclined beyond these limits, the eye trajectory tended to follow the axis inclination. In the upside down position, the maculo-ocular reflex was anticompensatory, oblique and fixed with respect to orbital coordinates. 3) Ampullo-ocular reflex gain did not change with inclinations of the rotation and/or longitudinal animal axes. The ocular responses were consistently oriented to the stimulus plane. At intermediate frequencies the eye movement trajectory was elliptic because of directional differences between the ampullo- and maculo-ocular reflexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Petrological Constraints on Melt Generation Beneath the Asal Rift (Djibouti)

NASA Astrophysics Data System (ADS)

Pinzuti, P.; Humler, E.; Manighetti, I.; Gaudemer, Y.; Bézos, A.

2010-12-01

The temporal evolution of the mantle melting processes in the Asal Rift is evaluated from the chemical composition of 95 lava flows sampled along 10 km of the rift axis and 8 km off-axis (that is for the last 650 ky). The major element composition and the trace element ratios of aphyric basalts across the Asal Rift show a symmetric pattern relative to the rift axis and preserved a clear signal of mantle melting depth variations. FeO, Fe8.0, Sm/YbN and Zr/Y increase, whereas SiO2 and Lu/HfN decrease from the rift axis to the rift shoulders. These variations are qualitatively consistent with a shallower melting beneath the rift axis than off-axis and the data show that the melting regime is inconsistent with a passive upwelling model. In order to quantify the depth range and extent of melting, we invert Na8.0 and Fe8.0 contents of basalts based on a pure active upwelling model. Beneath the rift axis, melting paths are shallow, from 60 to 30 km. These melting paths are consistent with adiabatic melting in normal-temperature asthenosphere, beneath an extensively thinned mantle lithosphere. In contrast, melting on the rift shoulders occurred beneath a thick mantle lithosphere and required mantle solidus temperature 180°C hotter than normal (melting paths from 110 to 75 km). The calculated rate of lithospheric thinning is high (6.0 cm yr-1) and could explain the survival of a metastable garnet within the mantle at depth shallower than 90 km beneath the modern Asal Rift.

Longitudinal shapes of the tibia and femur are unrelated and variable.

PubMed

Howell, Stephen M; Kuznik, Kyle; Hull, Maury L; Siston, Robert A

2010-04-01

In general practice, short films of the knee are used to assess component position and define the entry point for intramedullary femoral alignment in TKAs; however, whether it is justified to use the short film commonly used in research settings and everyday practice as a substitute for the whole leg view is controversial and needs clarification. In 138 long leg CT scanograms we measured the angle formed by the anatomic axis of the proximal fourth of the tibia and the mechanical axis of the tibia, the angle formed by the anatomic axis of the distal fourth of the femur and the mechanical axis of the femur, the "bow" of the tibia (as reflected by the offset of the anatomic axis from the center of the talus), and the "bow" of the femur (as reflected by the offset of the anatomic axis from the center of the femoral head). Because the angle formed by these axes and the bow of the tibia and femur have wide variability in females and males, a short film of the knee should not be used in place of the whole leg view when accurate assessment of component position and limb alignment is essential. A previous study of normal limbs found that only 2% of subjects have a neutral hip-knee-ankle axis, which can be explained by the wide variability of the bow in the tibia and femur and the lack of correlation between the bow of the tibia and femur in a given limb as shown in the current study.

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.

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.

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.

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.

Preliminary Paleomagnetically Determined Vertical-Axis Rotations and their Relationship to Extensional Events of the Southern Walker Lane

NASA Astrophysics Data System (ADS)

Johnson, S.; Geissman, J. W.; Katopody, D. T.; Kerstetter, S. R.; Oldow, J. S.

2016-12-01

The northern part of the southern Walker Lane experienced three extensional events from the late Oligocene to the Holocene: 1) late Oligocene to early Miocene WNW and ENE trending half-grabens, 2) Late Miocene to early Pliocene high-magnitude extension on a low-angle normal fault, and 3) contemporary transtensional deformation that initiated at 4 Ma. Each of the extensional events controlled deposition of synextensional strata. What is less understood is the timing and magnitude of vertical axis rotation and its relationship to each of the three extensional events. As part of a recent and ongoing multidisciplinary study to better understand the complex nature and history of these extensional events we present preliminary paleomagnetic data from 55 sites in Miocene extrusive igneous rocks which record that clockwise vertical-axis rotation played a significant role in accommodating displacement in these systems. Recently refined stratigraphic, geochronologic, and structural controls have allowed the detailed paleomagnetic sampling required for this study. We seek to provide better constraints on timing, areal extent, and distribution of vertical axis rotation to answer how vertical axis rotation interacted with these extensional events. Consistent with past studies, we have recognized 20-30 degrees of clockwise vertical-axis rotation distributed heterogeneously throughout the study area. However, clockwise vertical-axis rotations are no longer occurring in this region as evidenced by modern geodetic velocity fields. The accommodation of displacement by vertical axis rotations in this region likely ceased by early Pliocene to late Miocene when the structural step-over migrated to the northwest to its present day manifestation in the Mina Deflection. Anisotropy of magnetic susceptibility (AMS), used as a proxy for flow direction in igneous extrusive rocks, provides evidence that at least one late Oligocene-early Miocene half-grabens acted as near-source depositional centers concurrent with extension.

Accuracy in identifying the elbow rotation axis on simulated fluoroscopic images using a new anatomical landmark.

PubMed

Wiggers, J K; Snijders, R M; Dobbe, J G G; Streekstra, G J; den Hartog, D; Schep, N W L

2017-11-01

External fixation of the elbow requires identification of the elbow rotation axis, but the accuracy of traditional landmarks (capitellum and trochlea) on fluoroscopy is limited. The relative distance (RD) of the humerus may be helpful as additional landmark. The first aim of this study was to determine the optimal RD that corresponds to an on-axis lateral image of the elbow. The second aim was to assess whether the use of the optimal RD improves the surgical accuracy to identify the elbow rotation axis on fluoroscopy. CT scans of elbows from five volunteers were used to simulate fluoroscopy; the actual rotation axis was calculated with CT-based flexion-extension analysis. First, three observers measured the optimal RD on simulated fluoroscopy. The RD is defined as the distance between the dorsal part of the humerus and the projection of the posteromedial cortex of the distal humerus, divided by the anteroposterior diameter of the humerus. Second, eight trauma surgeons assessed the elbow rotation axis on simulated fluoroscopy. In a preteaching session, surgeons used traditional landmarks. The surgeons were then instructed how to use the optimal RD as additional landmark in a postteaching session. The deviation from the actual rotation axis was expressed as rotational and translational error (±SD). Measurement of the RD was robust and easily reproducible; the optimal RD was 45%. The surgeons identified the elbow rotation axis with a mean rotational error decreasing from 7.6° ± 3.4° to 6.7° ± 3.3° after teaching how to use the RD. The mean translational error decreased from 4.2 ± 2.0 to 3.7 ± 2.0 mm after teaching. The humeral RD as additional landmark yielded small but relevant improvements. Although fluoroscopy-based external fixator alignment to the elbow remains prone to error, it is recommended to use the RD as additional landmark.

Ocular residual and corneal astigmatism in a clinical population of high school students.

PubMed

Chen, Zhao; Liu, Luoru; Pan, Chenglin; Li, Xiaoning; Pan, Lun; Lan, Weizhong; Yang, Zhikuan

2018-01-01

Total refractive astigmatism is usually the first consideration that guides the selection of contact lens type (e.g., spherical or toric), while the ocular source of the astigmatism is a second, but more important consideration, for the final clinical decision. This study was conducted to provide detailed data on this topic by evaluating astigmatic components in Chinese adolescents. Participants were recruited from healthy high school students undergoing an annual ocular examination at a local hospital. Total astigmatism (TA), corneal astigmatism (CA), and ocular residual astigmatism (ORA) were determined by a Hartmann-Shack wavefront analyzer system (KR-1W, Topcon) with the natural pupil. The axis relationship between CA and ORA was placed into three categories: on-axis, defined as an axis with a difference of 0 ± 10°; opposite-axis, a difference of 90 ± 10°; and the rest defined as oblique-axis. The study consisted of 1,466 students (57.84% girls, age: 16.49 ± 1.05 years). ORA was present in 83.97%, 66.64%, and 45.23% of participants, according to the various criteria for astigmatism (≥ 0.50 D, ≥ 0.75 D, and ≥ 1.00 D, respectively). While with-the-rule was the most common axis orientation for both TA (76.28%) and CA (89.94%), against-the-rule predominated in ORA (93.82%; χ2 = 1688.544, p < 0.001). Opposite-axis was the major type of axis difference (90.96%) of clinical significance (i.e., ≥ 1.00 D) between CA and ORA, which also prevailed in all levels of TA (range: 56.25-82.26%). ORA is common in high school students and usually demonstrates a compensation relationship with CA, which should be taken into consideration when determining the design of contact lenses to correct refractive error.

A UNIFIED FRAMEWORK FOR THE ORBITAL STRUCTURE OF BARS AND TRIAXIAL ELLIPSOIDS

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

Valluri, Monica; Abbott, Caleb; Shen, Juntai

We examine a large random sample of orbits in two self-consistent simulations of N-body bars. Orbits in these bars are classified both visually and with a new automated orbit classification method based on frequency analysis. The well-known prograde x1 orbit family originates from the same parent orbit as the box orbits in stationary and rotating triaxial ellipsoids. However, only a small fraction of bar orbits (∼4%) have predominately prograde motion like their periodic parent orbit. Most bar orbits arising from the x1 orbit have little net angular momentum in the bar frame, making them equivalent to box orbits in rotatingmore » triaxial potentials. In these simulations a small fraction of bar orbits (∼7%) are long-axis tubes that behave exactly like those in triaxial ellipsoids: they are tipped about the intermediate axis owing to the Coriolis force, with the sense of tipping determined by the sign of their angular momentum about the long axis. No orbits parented by prograde periodic x2 orbits are found in the pure bar model, but a tiny population (∼2%) of short-axis tube orbits parented by retrograde x4 orbits are found. When a central point mass representing a supermassive black hole (SMBH) is grown adiabatically at the center of the bar, those orbits that lie in the immediate vicinity of the SMBH are transformed into precessing Keplerian orbits that belong to the same major families (short-axis tubes, long-axis tubes and boxes) occupying the bar at larger radii. During the growth of an SMBH, the inflow of mass and outward transport of angular momentum transform some x1 and long-axis tube orbits into prograde short-axis tubes. This study has important implications for future attempts to constrain the masses of SMBHs in barred galaxies using orbit-based methods like the Schwarzschild orbit superposition scheme and for understanding the observed features in barred galaxies.« less

Activation of 5-HT1A receptors in the rat dorsomedial hypothalamus inhibits stress-induced activation of the hypothalamic-pituitary-adrenal axis.

PubMed

Stamper, Christopher E; Hassell, James E; Kapitz, Adam J; Renner, Kenneth J; Orchinik, Miles; Lowry, Christopher A

2017-03-01

Acute activation of the hypothalamic-pituitary-adrenal (HPA) axis, leading to the release of corticosteroid hormones into the circulation, is an adaptive response to perceived threats. Persistent activation of the HPA axis can lead to impaired physiological or behavioral function with maladaptive consequences. Thus, efficient control and termination of stress responses is essential for well-being. However, inhibitory control mechanisms governing the HPA axis are poorly understood. Previous studies suggest that serotonergic systems, acting within the medial hypothalamus, play an important role in inhibitory control of stress-induced HPA axis activity. To test this hypothesis, we surgically implanted chronic jugular cannulae in adult male rats and conducted bilateral microinjection of vehicle or the 5-HT 1A receptor agonist, 8-hydroxy-2-(di-n-propylamino) tetralin hydrobromide (8-OH-DPAT; 8 nmol, 0.2 μL, 0.1 μL/min, per side) into the dorsomedial hypothalamus (DMH) immediately prior to a 40 min period of restraint stress. Repeated blood sampling was conducted using an automated blood sampling system and plasma corticosterone concentrations were determined using enzyme-linked immunosorbent assay. Bilateral intra-DMH microinjections of 8-OH-DPAT suppressed stress-induced increases in plasma corticosterone within 10 min of the onset of handling prior to restraint and, as measured by area-under-the-curve analysis of plasma corticosterone concentrations, during the 40 min period of restraint. These data support an inhibitory role for serotonergic systems, acting within the DMH, on stress-induced activation of the HPA axis. Lay summary: Inhibitory control of the hypothalamic-pituitary-adrenal (HPA) stress hormone response is important for well-being. One neurochemical implicated in inhibitory control of the HPA axis is serotonin. In this study we show that activation of serotonin receptors, specifically inhibitory 5-HT 1A receptors in the dorsomedial hypothalamus, is sufficient to inhibit stress-induced HPA axis activity in rats.

Ocular residual and corneal astigmatism in a clinical population of high school students

PubMed Central

Liu, Luoru; Pan, Chenglin; Li, Xiaoning; Pan, Lun; Yang, Zhikuan

2018-01-01

Purpose Total refractive astigmatism is usually the first consideration that guides the selection of contact lens type (e.g., spherical or toric), while the ocular source of the astigmatism is a second, but more important consideration, for the final clinical decision. This study was conducted to provide detailed data on this topic by evaluating astigmatic components in Chinese adolescents. Methods Participants were recruited from healthy high school students undergoing an annual ocular examination at a local hospital. Total astigmatism (TA), corneal astigmatism (CA), and ocular residual astigmatism (ORA) were determined by a Hartmann-Shack wavefront analyzer system (KR-1W, Topcon) with the natural pupil. The axis relationship between CA and ORA was placed into three categories: on-axis, defined as an axis with a difference of 0 ± 10°; opposite-axis, a difference of 90 ± 10°; and the rest defined as oblique-axis. Results The study consisted of 1,466 students (57.84% girls, age: 16.49 ± 1.05 years). ORA was present in 83.97%, 66.64%, and 45.23% of participants, according to the various criteria for astigmatism (≥ 0.50 D, ≥ 0.75 D, and ≥ 1.00 D, respectively). While with-the-rule was the most common axis orientation for both TA (76.28%) and CA (89.94%), against-the-rule predominated in ORA (93.82%; χ2 = 1688.544, p < 0.001). Opposite-axis was the major type of axis difference (90.96%) of clinical significance (i.e., ≥ 1.00 D) between CA and ORA, which also prevailed in all levels of TA (range: 56.25–82.26%). Conclusions ORA is common in high school students and usually demonstrates a compensation relationship with CA, which should be taken into consideration when determining the design of contact lenses to correct refractive error. PMID:29630629

Three-dimensional finite element analysis of occipitocervical fixation using an anterior occiput-to-axis locking plate system: a pilot study.

PubMed

Cai, Xianhua; Yu, Yang; Liu, Zhichao; Zhang, Meichao; Huang, Weibing

2014-08-01

Although there are many techniques for occipitocervical fixation, there have been no reports regarding occipitocervical fixation via the use of an anterior anatomical locking plate system. The biomechanics of this new system were analyzed by a three-dimensional finite element to provide a theoretical basis for clinical application. This was a modeling study. We studied a 27-year-old healthy male volunteer in whom cervical disease was excluded via X-ray examination. The states of stress and strain of these two internal fixation devices were analyzed. A three-dimensional finite element model of normal occiput-C2 was established based on the anatomical data from a Chinese population. An unstable model of occipital-cervical region was established by subtracting several unit structures from the normal model. An anterior occiput-to-axis locking titanium plate system was then applied and an anterior occiput-to-axis screw fixation was performed on the unstable model. Limitation of motion was performed on the surface of the fixed model, and physiological loads were imposed on the surface of the skull base. Under various loads from different directions, the peak values of displacement of the anterior occiput-to-axis locking titanium plate system decreased 15.5%, 12.5%, 14.4%, and 23.7%, respectively, under the loads of flexion, extension, lateral bending, and axial rotation. Compared with the anterior occiput-to-axis screw fixation, the peak values of stress of the anterior occiput-to-axis locking titanium plate system also decreased 3.9%, 2.9%, 9.7%, and 7.2%, respectively, under the loads of flexion, extension, lateral bending, and axial rotation. The anterior occiput-to-axis locking titanium plate system proved superior to the anterior occiput-to-axis screw system both in the stress distribution and fixation stability based on finite element analysis. It provides a new clinical option for anterior occipitocervical fixation. Copyright © 2014 Elsevier Inc. All rights reserved.

[How safe are orthoroentgenograms in determining the amount of correction for varus deformities?].

PubMed

Gürsu, Sarper; Yıldırım, Timur; Issın, Ahmet; Sofu, Hakan; Sahin, Vedat

2014-01-01

In this study, we evaluated the effects of the distance of the legs from the midline on alignment and angles of the lower extremities in orthoroentgenograms. Between March 2012 and April 2013, 95 limbs of 56 patients with varus deformity who underwent orthoroentgenogram to identify the amount of joint laxity in two positions were included in this study. The initial X-ray was performed with the feet in contact, while the other was performed as the legs were abducted to be in line with the shoulders. For each orthoroentgenogram, the mean mechanical axis angle, anatomical axis, and joint line orientation angles were measured retrospectively. These measurements were repeated for 43 limbs with varus deformity >10°. In the orthoroentgenograms with the feet in contact, the mean mechanical axis angle was 9.58°±5.7°, (0.20°; 26.0°), the mean anatomical axis angle 3.65°±6.14°, (-9.0°; 21.0°), and the mean joint line orientation angle -3.41°±2.52°, (-12.0°; 1.60°). In the orthoroentgenograms with the legs abducted, the mean mechanical axis angle was 7.73°±5.58°, (-3.0°; 23.0°), the mean anatomical axis angle 2.62°±5.87°, (-11.0°; 18.30°), and mean joint line orientation angle was -2.44°±2.41°, (-13.0°; 3.0°). The differences in the angles between the two positions were statistically significant (p<0.005). Our study results showed that the mean values of mechanical axis angle, anatomical axis and the joint line orientation angle were higher in orthoroentgenograms with the feet in contact than the orthoroentgenograms with the legs abducted in patients with varus gonarthrosis. We suggest that this may lead to mistakes in the preoperative planning. Ideal positions should be standardized to minimize possible problems.

Interaction of PGHS-2 and glutamatergic mechanisms controlling the ovine fetal hypothalamus-pituitary-adrenal axis

PubMed Central

Knutson, Nathan

2010-01-01

Prostaglandins, generated within the fetal brain, are integral components of the mechanism controlling the fetal hypothalamus-pituitary-adrenal (HPA) axis. Previous studies in this laboratory demonstrated that prostaglandin G/H synthase isozyme 2 (PGHS-2) inhibition reduces the fetal HPA axis response to cerebral hypoperfusion, blocks the preparturient rise in fetal plasma ACTH concentration, and delays parturition. We also discovered that blockade of N-methyl-d-aspartate (NMDA) receptors reduces the fetal ACTH response to cerebral hypoperfusion. The present study was designed to test the hypothesis that PGHS-2 action and the downstream effect of HPA axis stimulation are stimulated by NMDA-mediated glutamatergic neurotransmission. Chronically catheterized late-gestation fetal sheep (n = 8) were injected with NMDA (1 mg iv). All responded with increases in fetal plasma ACTH and cortisol concentrations. Pretreatment with resveratrol (100 mg iv, n = 5), a specific inhibitor of PGHS-1, did not alter the magnitude of the HPA axis response to NMDA. Pretreatment with nimesulide (10 mg iv, n = 6), a specific inhibitor of PGHS-2, significantly reduced the HPA axis response to NMDA. To further explore this interaction, we injected NMDA in six chronically catheterized fetal sheep that were chronically infused with nimesulide (n = 6) at a rate of 1 mg/day into the lateral cerebral ventricle for 5–7 days. In this group, there was no significant ACTH response to NMDA. Finally, we tested whether the HPA axis response to prostaglandin E2 (PGE2) is mediated by NMDA receptors. Seven chronically catheterized late-gestation fetal sheep were injected with 100 ng of PGE2, which significantly increased fetal plasma ACTH and cortisol concentrations. Pretreatment with ketamine (10 mg iv), an NMDA antagonist, did not alter the ACTH or cortisol response to PGE2. We conclude that generation of prostanoids via the action of PGHS-2 in the fetal brain augments the fetal HPA axis response to NMDA-mediated glutamatergic stimulation. PMID:20445154

T-wave axis deviation, metabolic syndrome and estimated cardiovascular risk--in men and women of the MOLI-SANI study.

PubMed

Rago, Livia; Di Castelnuovo, Augusto; Assanelli, Deodato; Badilini, Fabio; Vaglio, Martino; Gianfagna, Francesco; Salvetti, Massimo; Zito, Francesco; Alessandrini, Francesco; Donati, Maria Benedetta; de Gaetano, Giovanni; Iacoviello, Licia

2013-02-01

We aimed at investigating the association between T-wave axis deviation, metabolic syndrome (MetS), its components and estimated risk of cardiovascular disease (CVD) at 10 years in an adult Italian population. 11,143 women (54 ± 11 years) and 9742 men (55 ± 11 years) were analyzed from the Moli-sani cohort, randomly recruited from the general population. MetS was defined using the ATPIII criteria. T-wave axis deviation was measured from the standard 12-lead resting electrocardiogram. CVD risk in ten years was estimated by the CUORE score. 29% of men and 27% of women with MetS showed borderline or abnormal T-wave as compared to 24% and 17% without MetS (p < 0.0001 for both genders). Among components of MetS, elevated waist and blood pressure were strongly associated with T-wave axis deviation, whereas glucose, HDL and triglycerides were only marginally. The odds of having borderline or abnormal T-wave axis deviation in multivariable regression analysis, was 1.38 (95% CI:1.25-1.53) in MetS men and 1.68 (95% CI:1.51-1.87) in MetS women compared to those without. Further adjustment for MetS components completely abolished the associations. Abnormal T-wave axis deviation was associated with an increased risk of CVD in 10 years in men (OR = 4.4; 95% CI:1.10-17.9). T-wave axis deviation is strongly associated with components of the MetS, in particular high waist circumference and blood pressure and with an increased CVD risk, particularly in men. ECG monitoring to identify T-wave axis deviation in obese, hypertensive or MetS subjects can be an early indicator of vascular disease and help in reducing cardiac events. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Mechanisms of strain accommodation in plastically-deformed zircon under simple shear deformation conditions during amphibolite-facies metamorphism

NASA Astrophysics Data System (ADS)

Kovaleva, Elizaveta; Klötzli, Urs; Wheeler, John; Habler, Gerlinde

2018-02-01

This study documents the strain accommodation mechanisms in zircon under amphibolite-facies metamorphic conditions in simple shear. Microstructural data from undeformed, fractured and crystal-plastically deformed zircon crystals are described in the context of the host shear zone, and evaluated in the light of zircon elastic anisotropy. Our work challenges the existing model of zircon evolution and shows previously undescribed rheological characteristics for this important accessory mineral. Crystal-plastically deformed zircon grains have axis oriented parallel to the foliation plane, with the majority of deformed grains having axis parallel to the lineation. Zircon accommodates strain by a network of stepped low-angle boundaries, formed by switching between tilt dislocations with the slip systems <100>{010} and < 1 bar 10>{110} and rotation axis [001], twist dislocations with the rotation axis [001], and tilt dislocations with the slip system <100>{001} and rotation axis [010]. The slip system < 1 bar 10>{110} is newly described for zircon. Most misorientation axes in plastically-deformed zircon grains are parallel to the XY plane of the sample and have [001] crystallographic direction. Such behaviour of strained zircon lattice is caused by elastic anisotropy that has a direct geometric control on the rheology, deformation mechanisms and dominant slip systems in zircon. Young's modulus and P wave velocity have highest values parallel to zircon [001] axis, indicating that zircon is elastically strong along this direction. Poisson ratio and Shear modulus demonstrate that zircon is also most resistant to shearing along [001]. Thus, [001] axis is the most common rotation axis in zircon. The described zircon behaviour is important to take into account during structural and geochronological investigations of (poly)metamorphic terrains. Geometry of dislocations in zircon may help reconstructing the geometry of the host shear zone(s), large-scale stresses in the crust, and, possibly, the timing of deformation, if the isotopic systems of deformed zircon were reset.

Variations in the axis of motion during head repositioning--a comparison of subjects with whiplash-associated disorders or non-specific neck pain and healthy controls.

PubMed

Grip, Helena; Sundelin, Gunnevi; Gerdle, Björn; Karlsson, J Stefan

2007-10-01

The ability to reproduce head position can be affected in patients after a neck injury. The repositioning error is commonly used as a measure of proprioception, but variations in the movement might provide additional information. The axis of motion and target performance were analyzed during a head repositioning task (flexion, extension and side rotations) for 24 control subjects, 22 subjects with whiplash-associated disorders and 21 with non-specific neck pain. Questionnaires regarding pain intensity and fear avoidance were collected. Head position and axis of motion parameters were calculated using a helical axis model with a moving window of 4 degrees . During flexion the whiplash group had a larger constant repositioning error than the control group (-1.8(2.9) degrees vs. 0.1(2.4) degrees , P=0.04). The axis was more inferior in both neck pain groups (12.0(1.6)cm vs. 14.5(2.0)cm, P<0.05) indicating movement at a lower level in the spine. Including pain intensity from shoulder and neck region as covariates showed an effect on the axis position (P=0.03 and 0.04). During axial rotation to the left there was more variation in axis direction for neckpain groups as compared with controls (4.0(1.7) degrees and 3.7(2.4) degrees vs. 2.3(1.9) degrees , P=0.01 and 0.05). No significant difference in fear avoidance was found between the two neck pain groups. Measuring variation in the axis of motion together with target performance gives objective measures on proprioceptive ability that are difficult to quantify by visual inspection. Repositioning errors were in general small, suggesting it is not sufficient as a single measurement variable in a clinical situation, but should be measured in combination with other tests, such as range of motion.

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.

Design of a coil satellite centrifuge and its performance on counter-current chromatographic separation of 4-methylumbelliferyl sugar derivatives with polar organic-aqueous two-phase solvent systems.

PubMed

Shinomiya, Kazufusa; Tokura, Koji; Kimura, Emiru; Takai, Midori; Harikai, Naoki; Yoshida, Kazunori; Yanagidaira, Kazuhiro; Ito, Yoichiro

2015-05-01

A new high-speed counter-current chromatograph, named coil satellite centrifuge (CSC), was designed and fabricated in our laboratory. The CSC apparatus produces the satellite motion such that the coiled column simultaneously rotates around the sun axis (the angular velocity, ω1), the planet axis (ω2) and the satellite axis (the central axis of the column) (ω3). In order to achieve this triplicate rotary motion without twisting of the flow tube, the rotation of each axis was determined by the following formula: ω1=ω2+ω3. This relation enabled to lay out the flow tube without twisting by the simultaneous rotation of three axes. The flow tube was introduced from the bottom side of the apparatus into the sun axis of the first rotary frame reaching the upper side of the planet axis and connected to the column in the satellite axis. The performance of the apparatus was examined on separation of 4-methylumbelliferyl (MU) sugar derivatives as test samples with organic-aqueous two-phase solvent systems composed of ethyl acetate/1-butanol/water (3:2:5, v/v) for lower phase mobile and (1:4:5, v/v) for upper phase mobile. With lower phase mobile, five 4-MU sugar derivatives including β-D-cellobioside (Cel), β-D-glucopyranoside, α-D-mannopyranoside, β-D-fucopyranoside and α-L-fucopyranoside (α-L-Fuc) were separated with the combined rotation around each axis at counterclockwise (CCW) (ω1) - CCW (ω2) - CCW (ω3) by the flow tube distribution. With upper phase mobile, three 4-MU sugar derivatives including α-L-Fuc, β-D-galactopyranoside and Cel were separated with the combined rotation around each axis at clockwise (CW) (ω1) - CW (ω2) - CW (ω3) by the flow tube distribution. A series of experiments on peak resolution and stationary phase retention revealed that better partition efficiencies were obtained at the flow rate of 0.5 mL/min (column 1) and 0.8 mL/min (column 2) for lower phase mobile and 0.2 mL/min (column 1) and 0.4 mL/min (column 2) for upper phase mobile when using the left-handed multilayer coil (total capacity: 57.0 mL for column 1 and 75.0 mL for column 2) under the rotation speeds of approximately ω1=300 rpm, ω2=150 rpm and ω3=150 rpm. Copyright © 2015 Elsevier B.V. All rights reserved.

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 unmodified head rotation signal with a pure delay of 10 ms. Channel 2 conveys an angular head velocity signal, modified by viewing distance with a pure delay of 20 ms, but invariant with respect to the location of the axis of rotation. Channel 3 conveys a linear head velocity signal, dependent on the location of the axis of rotation, that is modified by viewing distance with a pure delay of 30 ms.(ABSTRACT TRUNCATED AT 400 WORDS)

The influence of isotropic and anisotropic crustal permeability on hydrothermal flow at fast spreading ridges

NASA Astrophysics Data System (ADS)

Hasenclever, Jörg; Rüpke, Lars; Theissen-Krah, Sonja; Morgan, Jason

2016-04-01

We use 3-D numerical models of hydrothermal fluid flow to assess the magnitude and spatial distribution of hydrothermal mass and energy fluxes within the upper and lower oceanic crust. A better understanding of the hydrothermal flow pattern (e.g. predominantly on-axis above the axial melt lens vs. predominantly off-axis and ridge-perpendicular over the entire crustal thickness) is essential for quantifying the volume of oceanic crust exposed to high-temperature fluid flow and the associated leaching and redistribution of economically interesting metals. The initial setup of all 3-D models is based on our previous 2-D studies (Theissen-Krah et al., 2011), in which we have coupled numerical models for crustal accretion and hydrothermal fluid flow. One result of these 2-D calculations is a crustal permeability field that leads to a thermal structure in the crust that matches seismic tomography data at the East Pacific Rise. Our reference 3-D model for hydrothermal flow at fast-spreading ridges predicts the existence of a hybrid hydrothermal system (Hasenclever et al., 2014) with two interacting flow components that are controlled by different physical mechanisms. 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% of the discharging fluid mass is replenished on-axis by warm (up to 300oC) recharge flow surrounding the hot thermal plumes. The remaining ˜40%, however, occurs as colder and broader recharge up to several kilometres away from the ridge axis that feeds hot (500-700oC) deep off-axis flow in the lower crust towards the ridge. Both flow components merge above the melt lens to feed ridge-centred vent sites. In a suite of 3-D model calculations we vary the isotropic crustal permeability to quantify its influence on on-axis vs. off-axis hydrothermal fluxes as well as on along-axis hydrothermal activity. We also explore the effect of anisotropic permeability that is likely to be a feature of the diking region above the melt lens where the repeated emplacement of meter-size dikes should lead to higher permeability in vertical and along-ridge direction and to lower permeability across the ridge. We further study the effect of along-ridge depth-variations of the axial melt lens on the distribution of hydrothermal vent sites.

A Z-axis recumbent rotating device for use in parabolic flight

NASA Technical Reports Server (NTRS)

Graybiel, A.; Miller, E. F., II

1976-01-01

A prototype apparatus for exposing persons to rotation about their Z-axis in parabolic flight is described. Although it resembles earth-horizontal axis devices, added features are its strength and portability, and the fiber glass 'couch' with adjustable elements providing support and restraint. Even under ground-based conditions, this device provides unique opportunities for investigations involving not only canalicular and macular mechanoreceptors, but also touch, pressure, and kinesthetic receptor systems.

Progress in geophysical aspects of the rotation of the earth

NASA Technical Reports Server (NTRS)

Lambeck, K.

1978-01-01

The geophysical causes and consequences of the Earth's rotation are reviewed. Specific topics covered include: (1) the motion of the rotation axis in space, precession and nutation; (2) the motion of the rotation axis relative to the Earth, polar motion; and (3) the rate of rotation about this axis, or changes in the length of day. Secular decrease in obliquity and evolution of the Earth-Moon system are also discussed.

Comparison Of Internal Adaptation Of Fixed Restorations Fabricated From Four Different Materials By A Three Axis Mill

DTIC Science & Technology

2016-06-26

COMP ARIS ON OF INTERNAL ADAPTATION OF FIXED RESTO RA TIO NS FABRICATED FROM FOUR DIFFERENT MATERIALS BY A THREE-AXIS MILL by Bryan Paul...copyrighted material in the thesis manuscript titled: COMPARISON OF INTERNAL ADAPTATION OF FIXED RESTORATIONS FABRICATED FROM FOUR DIFFERENT...RESTORATIONS FABRICATED FROM FOUR DIFFERENT MATERIALS BY A THREE-AXIS MILL LCDR Bryan Paul Rasmussen, DC USN Prosthodontics Dept., 2016 Directed by

Turbo Pascal/GEM Software Interface for Scientific Graph Preparation

DTIC Science & Technology

1991-04-01

Well as whatever artistic touches that the author may desire. Even colour hardcopy reproduuction is possible through use of an appropriate colour...drawing axes on graphs. The unit also contains an autoscaling procedure that may be applied separately to all curve axes. 6.3.1 Available structures...procedures AxisScale Provides autoscaled values from specified min and max values. LabelRightAxis Draws ticks and numbers on the right axis. LabelXAxis

Targeting Sphingosine-1-Phosphate Axis in Obesity-Promoted Breast Cancer

DTIC Science & Technology

2016-05-01

AWARD NUMBER: W81XWH-14-1-0071 TITLE: Targeting Sphingosine-1-Phosphate Axis in Obesity -Promoted Breast Cancer PRINCIPAL INVESTIGATOR...5a. CONTRACT NUMBER Targeting Sphingosine-1-Phosphate Axis in Obesity -Promoted Breast Cancer 5b. GRANT NUMBER W81XWH-14-1-0071 5c. PROGRAM ELEMENT...13. SUPPLEMENTARY NOTES 14. ABSTRACT Obesity , which induces low-grade inflammation, is a known risk factor for worse prognosis in many cancers

Off Axis Growth of Strontium Titanate Films with High Dielectric Constant Tuning and Low Loss

DTIC Science & Technology

2003-04-03

80309, U.S.A. ABSTRACT We have measured the nonlinear dielectric properties of strontium titanate (STO) thin films grown on neodymium gallate (NGO...and lanthanum aluminate (LAO) substrates. The films prepared by off-axis pulsed laser deposition were characterized by their dielectric constant and...performed on the films prepared with the off axis growth. EXPERIMENTAL Pulsed laser deposition (PLD) was used to deposit STO films on lanthanum

Targeting Trypsin-Inflammation Axis for Pancreatitis Therapy in a Humanized Pancreatitis Model

DTIC Science & Technology

2016-10-01

Award Number: W81XWH-15-1-0257 TITLE: Targeting Trypsin-Inflammation Axis for Pancreatitis Therapy in a Humanized Pancreatitis Model PRINCIPAL...AND SUBTITLE Targeting Trypsin-Inflammation Axis for Pancreatitis Therapy in a Humanized Pancreatitis Model 5a. CONTRACT NUMBER 5b. GRANT NUMBER...remains the same since it is covered under the institutional review. We set up monthly video conferences with our partnership PI to discuss any

Phosphor doping enhanced c-axis alignment and exchange decoupling of sputtered Co-Pt perpendicular thin films

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

Yang, Bo; Qin, Gaowu, E-mail: qingw@smm.neu.edu.cn; Xiao, Na

2016-04-14

In the present work, Co-23.0 at. % Pt and Co-23.0 at. % Pt-3.67 at. % P thin films with their c-axis perpendicular to the substrate surface were fabricated on a glass substrate by DC magnetron sputtering. X-ray diffraction and transmission electron microscopic analyses demonstrate that the doping of P improves the c-axis alignment and forms P-rich non-magnetic phase at grain boundary areas, the latter resulting in inter-granular exchange decoupling between Co-Pt grains. The improved c-axis alignment and the inter-granular exchange decoupling give rise to the increase of the out of plane coercivity and the squareness of the Co-Pt-P films.

Off-axis full-field swept-source optical coherence tomography using holographic refocusing

NASA Astrophysics Data System (ADS)

Hillmann, Dierck; Franke, Gesa; Hinkel, Laura; Bonin, Tim; Koch, Peter; Hüttmann, Gereon

2013-03-01

We demonstrate a full-field swept-source OCT using an off-axis geometry of the reference illumination. By using holographic refocusing techniques, a uniform lateral resolution is achieved over the measurement depth of approximately 80 Rayleigh lengths. Compared to a standard on-axis setup, artifacts and autocorrelation signals are suppressed and the measurement depth is doubled by resolving the complex conjugate ambiguity. Holographic refocusing was done efficiently by Fourier-domain resampling as demonstrated before in inverse scattering and holoscopy. It allowed to reconstruct a complete volume with about 10μm resolution over the complete measurement depth of more than 10mm. Off-axis full-field swept-source OCT enables high measurement depths, spanning many Rayleigh lengths with reduced artifacts.

DSM-III field trials: I. Initial interrater diagnostic reliability.

PubMed

Spitzer, R L; Forman, J B; Nee, J

1979-06-01

The interrater agreement for major diagnostic categories in studies using DSM-I and DSM-II was usually only fair or poor. In phase one of the DSM-III field trials the overall kappa coefficient of agreement for axis I diagnoses of 281 adult patients was .78 for joint interviews and .66 for diagnoses made after separate interviews; for axis II--personality disorders and specific developmental disorders--the coefficients of agreement were .61 and .54. The interrater reliability of DSM--III is, in general, higher than that previously achieved and may be due to changes in the classification itself, the separation of axis I from axis II conditions, the systematic description of the various disorders, and the inclusion of diagnostic criteria.

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

An improved integrally formed radio frequency quadrupole

DOEpatents

Abbott, S.R.

1987-10-05

An improved radio frequency quadrupole is provided having an elongate housing with an elongate central axis and top, bottom and two side walls symmetrically disposed about the axis, and vanes formed integrally with the walls, the vanes each having a cross-section at right angles to the central axis which tapers inwardly toward the axis to form electrode tips spaced from each other by predetermined distances. Each of the four walls, and the vanes integral therewith, is a separate structural element having a central lengthwise plane passing through the tip of the vane, the walls having flat mounting surfaces at right angles to and parallel to the control plane, respectively, which are butted together to position the walls and vane tips relative to each other. 4 figs.

The Mycobiome: A Neglected Component in the Microbiota-Gut-Brain Axis

PubMed Central

Enaud, Raphaël; Vandenborght, Louise-Eva; Coron, Noémie; Bazin, Thomas; Prevel, Renaud; Schaeverbeke, Thierry; Berger, Patrick; Fayon, Michael; Delhaes, Laurence

2018-01-01

In recent years, the gut microbiota has been considered as a full-fledged actor of the gut–brain axis, making it possible to take a new step in understanding the pathophysiology of both neurological and psychiatric diseases. However, most of the studies have been devoted to gut bacterial microbiota, forgetting the non-negligible fungal flora. In this review, we expose how the role of the fungal component in the microbiota-gut-brain axis is legitimate, through its interactions with both the host, especially with the immune system, and the gut bacteria. We also discuss published data that already attest to a role of the mycobiome in the microbiota-gut-brain axis, and the impact of fungi on clinical and therapeutic research. PMID:29522426

Three-dimensional scanning confocal laser microscope

DOEpatents

Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind

1999-01-01

A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

High-piezoelectric behavior of c-axis-oriented lead zirconate titanate thin films with composition near the morphotropic phase boundary

NASA Astrophysics Data System (ADS)

Fu, Desheng; Suzuki, Hisao; Ogawa, Takeshi; Ishikawa, Kenji

2002-05-01

The piezoelectric responses of c-axis-oriented Pb(Zr0.53Ti0.47)O3 (PZT) thin films have been studied by measuring the stress-induced charge with an accurate charge integrator. These measurements reveal that the c-axis-oriented PZT films have high values of d33, which are several times those of ceramic materials. The intrinsic d33 values of poled films are about 680 and 800 pC/N for the c-axis-oriented films on Si and MgO single-crystal substrates, respectively. It shows that the thin-film deposition technique opens an approach for exploring the potential superior properties of PZT near the morphotropic phase boundary.

Method and apparatus for characterizing and enhancing the dynamic performance of machine tools

DOEpatents

Barkman, William E; Babelay, Jr., Edwin F

2013-12-17

Disclosed are various systems and methods for assessing and improving the capability of a machine tool. The disclosure applies to machine tools having at least one slide configured to move along a motion axis. Various patterns of dynamic excitation commands are employed to drive the one or more slides, typically involving repetitive short distance displacements. A quantification of a measurable merit of machine tool response to the one or more patterns of dynamic excitation commands is typically derived for the machine tool. Examples of measurable merits of machine tool performance include dynamic one axis positional accuracy of the machine tool, dynamic cross-axis stability of the machine tool, and dynamic multi-axis positional accuracy of the machine tool.

Design of CMOS compatible and compact, thermally-compensated electro-optic modulator based on off-axis microring resonator for dense wavelength division multiplexing applications.

PubMed

Haldar, Raktim; Banik, Abhik D; Varshney, Shailendra K

2014-09-22

In this work, we propose and demonstrate the performance of silicon-on-insulator (SOI) off-axis microring resonator (MRR) as electro-optic modulator (EOM). Adding an extra off-axis inner-ring in conventional microring structure provides control to compensate thermal effects on EOM. It is shown that dynamically controlled bias-voltage applied to the outer ring has the potency to quell the thermal effects over a wide range of temperature. Thus, besides the appositely biased conventional microring, off-axis inner microring with pre-emphasized electrical input message signal enables our proposed structure suitable for high data-rate dense wavelength division multiplexing scheme of optical communication within a very compact device size.

Microgyroscope with closed loop output

NASA Technical Reports Server (NTRS)

Challoner, A. Dorian (Inventor); Gutierrez, Roman C. (Inventor); Tang, Tony K. (Inventor); Cargille, Donald R. (Inventor)

2002-01-01

A micro-gyroscope (10) having closed loop operation by a control voltage (V.sub.TY), that is demodulated by an output signal of the sense electrodes (S1, S2), providing Coriolis torque rebalance to prevent displacement of the micro-gyroscope (10) on the output axis (y-axis). The present invention provides wide-band, closed-loop operation for a micro-gyroscope (10) and allows the drive frequency to be closely tuned to a high Q sense axis resonance. A differential sense signal (S1-S2) is compensated and fed back by differentially changing the voltage on the drive electrodes to rebalance Coriolis torque. The feedback signal is demodulated in phase with the drive axis signal (K.sub..omega..crclbar..sub.x) to produce a measure of the Coriolis force.

Design of a novel coil satellite centrifuge and its performance on counter-current chromatographic separation of 4-methylumbelliferyl sugar derivatives with organic-aqueous two-phase solvent systems

PubMed Central

Shinomiya, Kazufusa; Tokura, Koji; Kimura, Emiru; Takai, Midori; Harikai, Naoki; Yoshida, Kazunori; Yanagidaira, Kazuhiro; Ito, Yoichiro

2015-01-01

A new high-speed counter-current chromatograph, named coil satellite centrifuge (CSC), was designed and fabricated in our laboratory. The CSC apparatus produces the satellite motion such that the coiled column simultaneously rotates around the sun axis (the angular velocity, ω1), the planet axis (ω2) and the satellite axis (the central axis of the column) (ω3). In order to achieve this triplicate rotary motion without twisting of the flow tube, the rotation of each axis was determined by the following formula: ω1 = ω2 + ω3. This relation enabled to lay out the flow tube by two different ways, the SS type and the JS type. In the SS type, the flow tube was introduced from the upper side of the apparatus into the sun axis of the first rotary frame and connected to the planet axis of the second rotary frame like a double letter SS. In the JS type, the flow tube was introduced from the bottom of the apparatus into the sun axis reaching the upper side of the planet axis an inversed letter J, followed by distribution as in the SS type. The performance of the apparatus was examined on separation of 4-methylumbelliferyl (MU) sugar derivatives as test samples with organic-aqueous two-phase solvent systems composed of ethyl acetate/1-butanol/water (3 : 2 : 5, v/v) for lower phase mobile and (1 : 4 : 5, v/v) for upper phase mobile. With lower phase mobile, five 4-MU sugar derivatives including β-D-cellobioside (Cel), β-D-glucopyranoside, α-D-mannopyranoside, β-D-fucopyranoside and α-L-fucopyranoside (α-L-Fuc) were separated with the combined rotation around each axis at counterclockwise (CCW) (ω1) – CCW (ω2) – CCW (ω3) by the JS type flow tube distribution. With upper phase mobile, three 4-MU sugar derivatives including α-L-Fuc, β-D-galactopyranoside and Cel were separated with the combined rotation around each axis at clockwise (CW) (ω1) – CW (ω2) – CW (ω3) by the JS type flow tube distribution. A series of experiments on peak resolution and stationary phase retention revealed that better partition efficiencies were obtained at the flow rate of 0.5 mL/min (column 1) and 0.8 mL/min (column 2) for lower phase mobile and 0.2 mL/min (column 1) and 0.4 mL/min (column 2) for upper phase mobile when using the left-handed multilayer coil (total capacity: 57.0 mL for column 1 and 75.0 mL for column 2) under the rotation speeds of approximately ω1 = 300 rpm, ω2 = 150 rpm and ω3 = 150 rpm. PMID:25805719

Perioperative Modulating Factors on Astigmatism in Sutured Cataract Surgery

PubMed Central

Cho, Yang Kyeung

2009-01-01

Purpose To evaluate the factors that affect postoperative astigmatism and post-suture removal astigmatism, and to evaluate the risk factors associated with astigmatism axis shift. Methods We performed a retrospective chart review of 130 eyes that had undergone uneventful phacoemulsification cataract surgery. Preoperative astigmatism was divided into four groups (Groups I, II, III, and IV) according to the differences between the axis of preoperative astigmatism (flattest axis) and the incision axis (105 degrees). We analyzed the magnitude and axis of the induced astigmatism after the operation and after suture removal in each group. We also analyzed the factors which affected the postoperative astigmatism and post-suture removal astigmatism in each sub-group of Groups I, II, III, and IV, excluding postoperative or post-suture removal axis shift (specifically, Group IWAS, IIWAS, IIIWAS, and IVWAS). We identified the variables associated with the prevalence of postoperative astigmatism axis shift and those associated with the prevalence of post-suture removal axis shift. Results An increase in the magnitude of postoperative astigmatism was associated with an increase in the preoperative magnitude of astigmatism in Groups IWAS, IIWAS, and IIIWAS (p<0.05), and with an increase in the corneal tunnel length in Group IWAS. A decrease in the magnitude of postoperative astigmatism was associated with an increase in the corneal tunnel length in Groups IIIWAS and IVWAS (p<0.05). An increase in the magnitude of post-suture removal astigmatism was associated with an increase in the magnitude of postoperative astigmatism in Groups IWAS and IVWAS (p<0.05), and with late suture removal in Group IVWAS (p<0.05). A decrease in the magnitude of post-suture removal astigmatism was associated with late suture removal in Groups IWAS and IIWAS. A logistic regression analysis showed that the prevalence of post-suture removal astigmatism axis shift was associated with increased corneal tunnel length, decreased magnitude of postoperative astigmatism, and early suture removal. Conclusions In order to reduce postoperative and post-suture removal astigmatism, we recommend a short corneal tunnel length and late suture removal in patients with Group IWAS characteristics, late suture removal in Group IIWAS-like patients, long corneal tunnel length in Group IIIWAS-like patients, and long corneal tunnel length and early suture removal in patients with characteristics of Group IVWAS. PMID:20046682

Cation-induced folding of alginate-bearing bilayer gels: an unusual example of spontaneous folding along the long axis.

PubMed

Athas, Jasmin C; Nguyen, Catherine P; Kummar, Shailaa; Raghavan, Srinivasa R

2018-04-04

The spontaneous folding of flat gel films into tubes is an interesting example of self-assembly. Typically, a rectangular film folds along its short axis when forming a tube; folding along the long axis has been seen only in rare instances when the film is constrained. Here, we report a case where the same free-swelling gel film folds along either its long or short axis depending on the concentration of a solute. Our gels are sandwiches (bilayers) of two layers: a passive layer of cross-linked N,N'-dimethylyacrylamide (DMAA) and an active layer of cross-linked DMAA that also contains chains of the biopolymer alginate. Multivalent cations like Ca2+ and Cu2+ induce these bilayer gels to fold into tubes. The folding occurs instantly when a flat film of the gel is introduced into a solution of these cations. The likely cause for folding is that the active layer stiffens and shrinks (because the alginate chains in it get cross-linked by the cations) whereas the passive layer is unaffected. The resulting mismatch in swelling degree between the two layers creates internal stresses that drive folding. Cations that are incapable of cross-linking alginate, such as Na+ and Mg2+, do not induce gel folding. Moreover, the striking aspect is the direction of folding. When the Ca2+ concentration is high (100 mM or higher), the gels fold along their long axis, whereas when the Ca2+ concentration is low (40 to 80 mM), the gels fold along their short axis. We hypothesize that the folding axis is dictated by the inhomogeneous nature of alginate-cation cross-linking, i.e., that the edges get cross-linked before the faces of the gel. At high Ca2+ concentration, the stiffer edges constrain the folding; in turn, the gel folds such that the longer edges are deformed less, which explains the folding along the long axis. At low Ca2+ concentration, the edges and the faces of the gel are more similar in their degree of cross-linking; therefore, the gel folds along its short axis. An analogy can be made to natural structures (such as leaves and seed pods) where stiff elements provide the directionality for folding.

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 perfectly compensatory VOR. PMID:16552499

Helical axis stellarator with noninterlocking planar coils

DOEpatents

Reiman, Allan; Boozer, Allen H.

1987-01-01

A helical axis stellarator using only noninterlocking planar, non-circular coils, generates magnetic fields having a magnetic well and large rotational transform with resultant large equilibrium beta.

Multi-Axis Identifiability Using Single-Surface Parameter Estimation Maneuvers on the X-48B Blended Wing Body

NASA Technical Reports Server (NTRS)

Ratnayake, Nalin A.; Koshimoto, Ed T.; Taylor, Brian R.

2011-01-01

The problem of parameter estimation on hybrid-wing-body type aircraft is complicated by the fact that many design candidates for such aircraft involve a large number of aero- dynamic control effectors that act in coplanar motion. This fact adds to the complexity already present in the parameter estimation problem for any aircraft with a closed-loop control system. Decorrelation of system inputs must be performed in order to ascertain individual surface derivatives with any sort of mathematical confidence. Non-standard control surface configurations, such as clamshell surfaces and drag-rudder modes, further complicate the modeling task. In this paper, asymmetric, single-surface maneuvers are used to excite multiple axes of aircraft motion simultaneously. Time history reconstructions of the moment coefficients computed by the solved regression models are then compared to each other in order to assess relative model accuracy. The reduced flight-test time required for inner surface parameter estimation using multi-axis methods was found to come at the cost of slightly reduced accuracy and statistical confidence for linear regression methods. Since the multi-axis maneuvers captured parameter estimates similar to both longitudinal and lateral-directional maneuvers combined, the number of test points required for the inner, aileron-like surfaces could in theory have been reduced by 50%. While trends were similar, however, individual parameters as estimated by a multi-axis model were typically different by an average absolute difference of roughly 15-20%, with decreased statistical significance, than those estimated by a single-axis model. The multi-axis model exhibited an increase in overall fit error of roughly 1-5% for the linear regression estimates with respect to the single-axis model, when applied to flight data designed for each, respectively.

Multileaf collimator tongue-and-groove effect on depth and off-axis doses: A comparison of treatment planning data with measurements and Monte Carlo calculations

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

Kim, Hee Jung; Department of Biomedical Engineering, Seoul National University, Seoul; Department of Radiation Oncology, Soonchunhyang University Hospital, Seoul

2015-01-01

To investigate how accurately treatment planning systems (TPSs) account for the tongue-and-groove (TG) effect, Monte Carlo (MC) simulations and radiochromic film (RCF) measurements were performed for comparison with TPS results. Two commercial TPSs computed the TG effect for Varian Millennium 120 multileaf collimator (MLC). The TG effect on off-axis dose profile at 3 depths of solid water was estimated as the maximum depth and the full width at half maximum (FWHM) of the dose dip at an interleaf position. When compared with the off-axis dose of open field, the maximum depth of the dose dip for MC and RCF rangedmore » from 10.1% to 20.6%; the maximum depth of the dose dip gradually decreased by up to 8.7% with increasing depths of 1.5 to 10 cm and also by up to 4.1% with increasing off-axis distances of 0 to 13 cm. However, TPS results showed at most a 2.7% decrease for the same depth range and a negligible variation for the same off-axis distances. The FWHM of the dose dip was approximately 0.19 cm for MC and 0.17 cm for RCF, but 0.30 cm for Eclipse TPS and 0.45 cm for Pinnacle TPS. Accordingly, the integrated value of TG dose dip for TPS was larger than that for MC and RCF and almost invariant along the depths and off-axis distances. We concluded that the TG dependence on depth and off-axis doses shown in the MC and RCF results could not be appropriately modeled by the TPS versions in this study.« less

Alterations in HPA-axis and autonomic nervous system functioning in childhood anxiety disorders point to a chronic stress hypothesis.

PubMed

Dieleman, Gwendolyn C; Huizink, Anja C; Tulen, Joke H M; Utens, Elisabeth M W J; Creemers, Hanneke E; van der Ende, Jan; Verhulst, Frank C

2015-01-01

It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia. Copyright © 2014 Elsevier Ltd. All rights reserved.

What Are “X-shaped” Radio Sources Telling Us? II. Properties of a Sample of 87

NASA Astrophysics Data System (ADS)

Saripalli, Lakshmi; Roberts, David H.

2018-01-01

In an earlier paper, we presented Jansky Very Large Array multi-frequency, multi-array continuum imaging of a unique sample of low-axial ratio radio galaxies. In this paper, the second in the series, we examine the images to learn the phenomenology of how the off-axis emission relates to the main radio source. Inversion-symmetric offset emission appears to be bimodal and to originate from one of two strategic locations: outer ends of radio lobes (outer-deviation) or from inner ends (inner-deviation). The latter sources are almost always associated with edge-brightened sources. With S- and Z-shaped sources being a subset of outer-deviation sources, this class lends itself naturally to explanations involving black hole axis precession. Our data allow us to present a plausible model for the more enigmatic inner-deviation sources with impressive wings; as for outer-deviation sources these too require black hole axis shifts, although they also require plasma backflows into relic channels. Evolution in morphology over time relates the variety in structures in inner-deviation sources including XRGs. With features such as non-collinearities, central inner-S “spine,” corresponding lobe emission peaks, double and protruding hotspots not uncommon, black hole axis precession, drifts, or flips could be active in a significant fraction of radio sources with prominent off-axis emission. At least 4% of radio galaxies appear to undergo black hole axis rotation. Quasars offer a key signature for recognizing rotating axes. With a rich haul of sources that have likely undergone axis rotation, our work shows the usefulness of low-axial ratio sources in pursuing searches for binary supermassive black holes.

Reactor Pressure Vessel Fracture Analysis Capabilities in Grizzly

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

Spencer, Benjamin; Backman, Marie; Chakraborty, Pritam

2015-03-01

Efforts have been underway to develop fracture mechanics capabilities in the Grizzly code to enable it to be used to perform deterministic fracture assessments of degraded reactor pressure vessels (RPVs). Development in prior years has resulted a capability to calculate -integrals. For this application, these are used to calculate stress intensity factors for cracks to be used in deterministic linear elastic fracture mechanics (LEFM) assessments of fracture in degraded RPVs. The -integral can only be used to evaluate stress intensity factors for axis-aligned flaws because it can only be used to obtain the stress intensity factor for pure Mode Imore » loading. Off-axis flaws will be subjected to mixed-mode loading. For this reason, work has continued to expand the set of fracture mechanics capabilities to permit it to evaluate off-axis flaws. This report documents the following work to enhance Grizzly’s engineering fracture mechanics capabilities for RPVs: • Interaction Integral and -stress: To obtain mixed-mode stress intensity factors, a capability to evaluate interaction integrals for 2D or 3D flaws has been developed. A -stress evaluation capability has been developed to evaluate the constraint at crack tips in 2D or 3D. Initial verification testing of these capabilities is documented here. • Benchmarking for axis-aligned flaws: Grizzly’s capabilities to evaluate stress intensity factors for axis-aligned flaws have been benchmarked against calculations for the same conditions in FAVOR. • Off-axis flaw demonstration: The newly-developed interaction integral capabilities are demon- strated in an application to calculate the mixed-mode stress intensity factors for off-axis flaws. • Other code enhancements: Other enhancements to the thermomechanics capabilities that relate to the solution of the engineering RPV fracture problem are documented here.« less

[Polar and non polar notations of refraction].

PubMed

Touzeau, O; Gaujoux, T; Costantini, E; Borderie, V; Laroche, L

2010-01-01

Refraction can be expressed by four polar notations which correspond to four different combinations of spherical or cylindrical lenses. Conventional expressions of refraction (plus and minus cylinder notation) are described by sphere, cylinder, and axis. In the plus cylinder notation, the axis visualizes the most powerful meridian. The axis usually corresponds to the bow tie axis in curvature maps. Plus cylinder notation is also valuable for all relaxing procedures (i.e., selective suture ablation, arcuate keratotomy, etc.). In the cross-cylinder notation, two orthogonal cylinders can describe (without the sphere component) the actual refraction of both the principal meridians. This notation must be made before performing the vertex calculation. Using an association of a Jackson cross-cylinder and a spherical equivalent, refraction can be broken down into two pure components: astigmatism and sphere. All polar notations of refraction may perfectly characterize a single refraction but are not suitable for statistical analysis, which requires nonpolar expression. After doubling the axis, a rectangular projection breaks down the Jackson cross-cylinder, which has a polar axis, into two Jackson cross-cylinders on the 0 degrees /90 degrees and 45 degrees /135 degrees axis. This procedure results in the loss of the directional nature of the data. Refraction can be written in a nonpolar notation by three rectangular coordinates (x,y,z), which can also represent the spherocylinder by one point in a dioptric space. These three independent (orthogonal) variables have a concrete optical significance: a spherical component, a direct/inverse (WTR/ATR) component, and an oblique component of the astigmatism. Finally, nonpolar notations are useful for statistical analysis and graphical representation of refraction. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

Anisotropy of the innermost inner core from body wave and normal mode observations

NASA Astrophysics Data System (ADS)

Deuss, A. F.; Smink, M.; Bouwman, D.; Ploegstra, J.; van Tent, R.

2016-12-01

It has been known for a long time that the Earth's inner core is cylindrically anisotropic, with waves that travel in the direction of the Earth's rotation axis arriving several seconds before waves travelling in the equatorial direction. Recently, several studies have suggested that the Earth's rotation axis may not be the fast anisotropy direction in the innermost inner core. Beghein and Trampert (2003) found that the Earth's rotation axis is slow, with the equatorial plane being fast. Wang et al (2015) found instead that the fast symmetry axis is in the equatorial plane. Here, we use both body wave and normal mode observations to test these two different hypotheses. Similar to Wang, we correct body wave PKIKP data for anisotropy in the upper inner core, and investigate if there is any anisotropy remaining in the innermost inner core. We find that the results strongly depend on the very limited number of polar direction waves with angle less than 25 degrees. With the limited data it is difficult to distinguish between the two different hypotheses, and if any tilted anisotropy is required at all. Normal modes see inner core anisotropy with north-south symmetry axis as anomalous zonal coefficients. We will show theoretically that if the anisotropy symmetry axis is tilted, non-zonal coefficients will also become anomalous. We search consistent anomalous non-zonal coefficients for modes sensitive to the innermost inner core. If the symmetry axis is still north south, but this is now the slow direction and the equatorial plane fast, then we predict negative zonal coefficients. This is observed for some normal modes, explaining why Beghein and Trampert (2003) found this type of anisotropy in the innermost inner core.

Immediate and prolonged effects of alcohol exposure on the activity of the hypothalamic-pituitary-adrenal axis in adult and adolescent rats

PubMed Central

ALLEN, Camryn D.; LEE, Soon; KOOB, George F.; RIVIER, Catherine

2011-01-01

Alcohol stimulates the hypothalamic-pituitary-adrenal (HPA) axis. Part of this influence is likely exerted directly at the level of the corticotropin-releasing factor (CRF) gene, but intermediates may also play a role. Here we review the effect of alcohol on this axis, provide new data on the effects of binge drinking during adolescence, and argue for a role of catecholaminergic circuits. Indeed, acute injection of this drug activates brain stem adrenergic and noradrenergic circuits, and their lesion, or blockade of α1 adrenergic receptors significantly blunts alcohol-induced ACTH release. As alcohol can influence the HPA axis even once discontinued, and alcohol consumption in young people is associated with increased adult drug abuse (a phenomenon possibly mediated by the HPA axis), we determined whether alcohol consumption during adolescence modified this axis. The number of CRF-immunoreactive (ir) cells/section was significantly decreased in the central nucleus of the amygdala of adolescent self-administering binge-drinking animals, compared to controls. When another group of adolescent binge-drinking rats was administered alcohol in adulthood, the number of colocalized c-fos-ir and PNMT-ir cells/brain stem section in the C3 area was significantly decreased, compared to controls. As the HPA axis response to alcohol is blunted in adult rats exposed to alcohol vapors during adolescence, a phenomenon which was not observed in our model of self-administration, it is possible that the blood alcohol levels achieved in various models play a role in the long-term consequences of exposure to alcohol early in life. Collectively, these results suggest an important role of brain catecholamines in modulating the short- and long-term consequences of alcohol administration. PMID:21300146

A low-voltage three-axis electromagnetically actuated micromirror for fine alignment among optical devices

NASA Astrophysics Data System (ADS)

Cho, Il-Joo; Yoon, Euisik

2009-08-01

In this paper, a new three-axis electromagnetically actuated micromirror structure has been proposed and fabricated. It is electromagnetically actuated at low voltage using an external magnetic field. The main purpose of this work was to obtain a three-axis actuated micromirror in a mechanically robust structure with large static angular and vertical displacement at low actuation voltage for fine alignment among optical components in an active alignment module as well as conventional optical systems. The mirror plate and torsion bars are made of bulk silicon using a SOI wafer, and the actuation coils are made of electroplated Au. The maximum static deflection angles were measured as ±4.2° for x-axis actuation and ±9.2° for y-axis actuation, respectively. The maximum static vertical displacement was measured as ±42 µm for z-axis actuation. The actuation voltages were below 3 V for all actuation. The simulated resonant frequencies are several kHz, and these imply that the fabricated micromirror can be operated in sub-millisecond order. The measured radius of curvature (ROC) of the fabricated micromirror is 7.72 cm, and the surface roughness of the reflector is below 1.29 nm which ensure high optical performance such as high directionality and reflectivity. The fabricated micromirror has demonstrated large actuated displacement at low actuation voltage, and it enables us to compensate a larger misalignment value when it is used in an active alignment module. The robust torsion bar and lifting bar structure formed by bulk silicon allowed the proposed micromirror to have greater operating stability. The additional degree of freedom with z-axis actuation can decrease the difficulty in the assembly of optical components and increase the coupling efficiency between optical components.

Petrological constraints on melt generation beneath the Asal Rift (Djibouti) using quaternary basalts

NASA Astrophysics Data System (ADS)

Pinzuti, Paul; Humler, Eric; Manighetti, Isabelle; Gaudemer, Yves

2013-08-01

The temporal evolution of the mantle melting processes in the Asal Rift is evaluated from the chemical composition of 56 new lava flows sampled along 10 km of the rift axis and 9 km off-axis (i.e., erupted within the last 620 kyr). Petrological and primary geochemical results show that most of the samples of the inner floor of the Asal Rift are affected by plagioclase accumulation. Trace element ratios and major element compositions corrected for mineral accumulation and crystallization show a symmetric pattern relative to the rift axis and preserved a clear signal of mantle melting depth variations. While FeO, Fe8.0, Zr/Y, and (Dy/Yb)N decrease from the rift shoulders to the rift axis, SiO2, Na/Ti, Lu/Hf increase and Na2O and Na8.0 are constant across the rift. These variations are qualitatively consistent with shallow melting beneath the rift axis and deeper melting for off-axis lava flows. Na8.0 and Fe8.0 contents show that beneath the rift axis, melting paths are shallow, from 81 ± 4 to 43 ± 5 km. These melting paths are consistent with adiabatic melting in normal-temperature fertile asthenosphere, beneath an extensively thinned mantle lithosphere. On the contrary, melting on the rift shoulders (from 107 ± 7 to 67 ± 8 km) occurred beneath thicker lithosphere, requiring a mantle solidus temperature 100 ± 40°C hotter. In this geodynamic environment, the calculated rate of lithospheric thinning appears to be 4.0 ± 2.0 cm yr-1, a value close to the mean spreading rate (2.9 ± 0.2 cm yr-1) over the last 620 kyr.