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At least 127 records · Page 7Linked to original sources
PubMed2004

Fatal attraction: the effects of mortality salience on evaluations of charismatic, task-oriented, and relationship-oriented leaders.

A study was conducted to assess the effects of mortality salience on evaluations of political candidates as a function of leadership style. On the basis of terror management theory and previous research, we hypothesized that people would show increased preference for a charismatic political candidate and decreased preference for a relationship-oriented political candidate in response to subtle reminders of death. Following a mortality-salience or control induction, 190 participants read campaign statements by charismatic, task-oriented, and relationship-oriented gubernatorial candidates; evaluated their preferences for each candidate; and voted for one of them. Results were in accord with predictions. The theoretical and practical implications of these findings are considered.

Adolescent↗
PubMed1995

Spatial orientation in the lamprey. II. Visual influence on orientation during locomotion and in the attached state

The responses of attached lampreys to homogeneous visual stimulation and the role of visual stimuli in orientation during locomotion were investigated. Experiments were performed by video recording the responses of intact and lesioned animals to illumination. The following results were obtained. 1. In lampreys attached with their sucker mouth to the bottom of the aquarium, illumination of one eye evoked several possible motor responses (ordered after mean latency): (a) movement of the illuminated eye downwards, and the contralateral eye upwards; (b) rotation of the body around the longitudinal axis, with the illuminated side tilting downwards; (c) deviation of the caudal part of the anterior dorsal fin in the contralateral direction (away from the light); and (d) flexion of the neck and body towards the side of illumination. 2. Illumination of one eye in attached lampreys often resulted in detachment and subsequent movement in a direction away from the light source (negative phototaxis). This response was not related to the degree of roll tilt before detachment, so the negative phototaxis does not appear to be a consequence of the vestibular stimulation. 3. Negative phototaxis was also seen during locomotion: lampreys turned through 180 ° when they approached a brightly illuminated area. Photostimulation also affected their orientation in the transverse plane during swimming. Illumination of one eye from the side induced a roll movement, so that the illuminated side tilted downwards and the dorsum of the lamprey became turned towards the light. This is similar to the 'dorsal light response' of fish and shows that vision also plays a role in postural control in lampreys. 4. The behaviour of blinded animals differed strikingly from that of intact ones. Whereas intact animals preferentially swam close to the bottom, along horizontal trajectories, blinded animals showed episodes of continuous swimming upwards, near the water surface. During horizontal swimming, their orientation in the transverse plane remained normal, with the dorsal side up.

Journal Article↗
PubMed2004

Tilt angles of transmembrane model peptides in oriented and non-oriented lipid bilayers as determined by 2H solid-state NMR.

Solid-state NMR methods employing (2)H NMR and geometric analysis of labeled alanines (GALA) were used to study the structure and orientation of the transmembrane alpha-helical peptide acetyl-GWW(LA)(8)LWWA-amide (WALP23) in phosphatidylcholine (PC) bilayers of varying thickness. In all lipids the peptide was found to adopt a transmembrane alpha-helical conformation. A small tilt angle of 4.5 degrees was observed in di-18:1-PC, which has a hydrophobic bilayer thickness that approximately matches the hydrophobic length of the peptide. This tilt angle increased slightly but systematically with increasing positive mismatch to 8.2 degrees in di-C12:0-PC, the shortest lipid used. This small increase in tilt angle is insufficient to significantly change the effective hydrophobic length of the peptide and thereby to compensate for the increasing hydrophobic mismatch, suggesting that tilt of these peptides in a lipid bilayer is energetically unfavorable. The tilt and also the orientation around the peptide axis were found to be very similar to the values previously reported for a shorter WALP19 peptide (GWW(LA)(6)LWWA). As also observed in this previous study, the peptide rotates rapidly around the bilayer normal, but not around its helix axis. Here we show that these properties allow application of the GALA method not only to macroscopically aligned samples but also to randomly oriented samples, which has important practical advantages. A minimum of four labeled alanine residues in the hydrophobic transmembrane sequence was found to be required to obtain accurate tilt values using the GALA method.

Alanine↗
PubMed1992

Psychometric properties of the Learning-Orientation Grade-Orientation II Scale.

The Learning-Orientation Grade-Orientation Scale of Eison, Pollio, and Milton was administered to 85 college students and analyzed to study the psychometric properties of the instrument. Scale means were consistent with those usually reported. Cronbach coefficients alpha for 5 of the 6 scales ranged from .58 to .70; however, the coefficient alpha for learning-orientation attitude scale was questionably low (.29). Item analyses and factor analyses support the continued use of at least 5 of the 6 scales measured by the inventory.

Achievement↗
PubMed1994

Assessment of change in scores on personal control orientation and use of drugs and alcohol of adolescents who participate in a cognitively oriented pretreatment intervention.

The primary purpose of this study was to assess the effect of participation in a cognitively oriented, pretreatment intervention on the control orientation of substance-using behavior of 48 adolescents admitted to drug-free outpatient treatment. Subjects were randomly assigned to one of two treatment conditions and to one of two counselors. A comparison of changes in control orientation between groups was made after implementation of the intervention with the treated group and after both groups had participated in six counseling sessions. A 2-way multivariate analysis of covariance showed type of treatment was significant. Follow-up analyses indicated the treated group were significantly more internal than the control group at both posttest occasions. A one-tailed chi-squared test indicated no significant association in substance use for the groups.

Adolescent↗
PubMed2000

Influence of castration and estrogen replacement on sexual behavior of female-oriented, male-oriented, and asexual rams.

An experiment was conducted to determine whether exogenous estradiol-17beta (E2) could restore sexual behavior in castrated rams. The protocol consisted of three sequential 6-wk periods during which rams were studied while 1) intact, 2) bilaterally castrated, or 3) implanted s.c. with two 7.6-cm silastic implants each containing 309+/-16 mg of E2. Rams (classified as female-oriented [FOR, n = 7], male-oriented [MOR, n = 7], or asexual [n = 7]) were subjected to 30-min sexual behavior tests every 2 wk during the ensuing 18 wk. Rams were observed for mounts and ejaculations using two ovariectomized, estrous ewes and two intact males secured in stanchions. Behavioral data were analyzed using the signed rank test, but asexual rams showed no sexual behavior and therefore were not evaluated statistically. Jugular blood was collected prior to castration and at the end of the 18-wk period, and testicular venous (n = 21) and arterial (n = 8) bloods were collected immediately prior to castration. Radioimmunoassay was used to quantify systemic levels of estrone (E1), E2, and testosterone (T) and testicular serum concentrations of oxytocin (OT). Mounting behavior of MOR and FOR declined after castration (P < .05 and P < .10, respectively). Castration reduced the number of ejaculations by FOR (P < .05), but not by MOR (P > .10). Mounting behavior of castrated MOR and FOR was not affected by E2 treatment relative to that observed if castrated only (P > .10). Treatment of asexual rams with E2 did not stimulate sexual behavior in these rams. There were no marked differences (P > .10) among ram groups with regard to serum concentrations of E1, E2, or T prior to castration (overall mean +/- SE, 12.8+/-.7, 7.6+/-.5, and 2,670+/-780 pg/mL, respectively) or any difference (P > .10) in systemic concentration of E1 or E2 among ram groups after rams were implanted with E2 (overall mean +/- SE, 9.7+/-.7 and 9.0 +/-.7 pg/mL, respectively). Serum concentrations of E2 after implantation of the steroid did not differ from those present while rams were intact (P > .10). Testicular venous and arterial serum concentrations of OT were low and did not differ within or between rams. These results suggest that restoration of E2 concentrations to physiological levels in castrated adult rams (regardless of sexual orientation) cannot stimulate or reestablish sexual behaviors to levels observed prior to castration.

Animals↗
PubMed2006

Comparison of cortisol, luteinizing hormone, and testosterone responses to a defined stressor in sexually inactive rams and sexually active female-oriented and male-oriented rams.

The objective of this study was to determine whether the effect of restraint stress on cortisol, LH, and testosterone varied among sexually inactive and sexually active female- and male-oriented rams, to allow differentiation among ram classes. Restraint stress or no stress was imposed on sexually inactive (n = 7) and sexually active female- (n = 17) and male-oriented (n = 6) rams in a 2 x 3 factorial arrangement. Rams were assigned to restraint or control within each classification. Rams were habituated to wearing halters and being tethered in separate pens, permitting visual, vocal, and olfactory contact with adjacent rams for 7 d before treatment. After 1 d of habituation, rams were fitted with jugular catheters that were checked twice daily for patency. For restraint stress, rams were laid on their side with their legs tied for 1 h. For no stress, rams were tethered with halters and leads, but their legs were not tied. On the treatment day, blood was collected at 30-min intervals for 3 h followed by 15-min intervals for 1 h before restraint, during 1-h restraint, and for 1 h after liberation from restraint. Then blood was collected at 30-min intervals for an additional 2 h. Blood was collected from controls at similar intervals. Control rams were isolated from stressed rams. Cortisol, LH, and testosterone were measured using RIA. Mixed model analyses with repeated measures were used on transformed data. Average prestress data were used as a covariate. Cortisol increased (P < 0.01) within 15 min after restraint and remained increased until 1.5 h after liberation from 1-h of restraint stress. In contrast, in controls cortisol remained unchanged at 5 ng/ mL. Cortisol did not differ over time among ram classes, and the treatment x ram class x time interaction was not significant. For LH and testosterone, the ram class x time interactions appeared to compromise the ability to identify differences in these hormones, indicating that they were not good endocrine candidates for methods of classifying rams. In conclusion, restraint stress increased cortisol in sexually inactive and sexually active female- and male-oriented rams alike, thus not providing a method to differentiate among ram classes.

Animals↗
PubMedDate not supplied

Object-orientated DBMS techniques for time-oriented medical record.

In implementing time-orientated medical record (TOMR) management systems, use of a relational model played a big role. Many applications have been developed to extend query and data manipulation languages to temporal aspects of information. Our experience in developing TOMR revealed some deficiencies inside the relational model, such as: (a) abstract data type definition; (b) unified view of data, at a programming level; (c) management of temporal data; (d) management of signals and images. We identified some first topics to face by an object-orientated approach to database design. This paper describes the first steps in designing and implementing a TOMR by an object-orientated DBMS.

Algorithms↗
PubMed1985

Measurement of erythrocyte orientation in flow by spin labeling III--erythrocyte orientation and rheological conditions.

The measurements of erythrocyte orientation, obtained through a spin labeling technique, are compared with a phenomenological model. Several rheological conditions are varied: hematocrit, suspending medium viscosity, blood age, artificial reversible aggregation. We found that the onset of orientation is very sensitive to any variation of these conditions, and that its measurement would be a good method to assess erythrocyte deformability. A critical shear rate for the orientation process is then determined and compared to the corresponding parameter obtained from viscosity measurements of identical suspensions. A close qualitative relationship is found between the two sets of values of the critical shear rate.

Biomechanical Phenomena↗
PubMed2003

[From disease-oriented andrology to health-oriented andrology].

One of the main current trends of andrology is the paradigm shift from disease-oriented to health-oriented andrology. One of the major tasks we are faced with now is to establish an holistic concept of male reproductive health, then, starting from the needs and demands of male reproductive health, to identify the scope of andrology, as well as to develop a new research priorities and agenda. The progress and perspective of three main areas in the field of health-oriented andrology, namely, molecular andrology, andrology for aging and environment and male reproduction, were briefly reviewed and discussed.

Aging↗
PubMed1993

Egocentric references and human spatial orientation in microgravity. II. Body-centred coordinates in the task of drawing ellipses with prescribed orientation.

This article describes the results of the "ellipses" experiment conducted during the second French-Soviet spaceflight (project Aragatz). The realization of oriented motor tasks, on the basis of internal body representation and without visual feedback, was chosen as a paradigm for studying the determinants of spatial orientation under weightlessness. The process of drawing ellipses in the air, using arm movements with axes parallel or perpendicular to the longitudinal body axis, was studied under normal gravity and in weightlessness, and recorded using a video computer motion-analyzing system (Kinesigraph). On Earth, the experiments were performed in standing and lying positions, and in flight, in the erect position with the feet fixed to the floor. In general, performance of the task in microgravity was not disturbed. Under conditions of spaceflight, the longitudinal ellipse was inclined forward in accordance with the inclination of the whole body relative to the fixed feet. On Earth, the angle between the long axes of longitudinal and transverse ellipses deviated from 90 degrees by 20-30 degrees. The same deviation persisted under microgravity conditions. The distinctive features of ellipses traced by individual subjects were also preserved. It is concluded that an egocentric reference system ensures normal performance of sensorimotor tasks in the absence of a gravitational reference.

Adaptation, Psychological↗
PubMed2002

Social attention orienting integrates visual information from head and body orientation.

Subjects were asked to detect visual, laterally presented reaction signals preceded by head-body cue stimuli in a spatial cueing task. A head rotated towards the reaction signal combined with a front view of a body resulted in shorter reaction times in comparison to the front view of a head and body. In contrast, a cue showing the head and body rotated towards the reaction signal did not result in such a facilitation in reaction times. The results suggest that the brain mechanisms involved in social attention orienting integrate ventrally processed visual information from the head and body orientation. A cue signaling that the other person, in his or her frame of reference, has an averted attention direction shifts the observer's own attention in the same direction.

Adult↗
PubMed2002

Orientation- and frequency-modulated textures at low depths of modulation are processed by off-orientation and off-frequency texture mechanisms.

Intuitively it may seem likely that orientation-modulated (OM) and frequency-modulated (FM) textures are processed utilizing the first-order channels that are most responsive to the first-order (luminance) information contained in the textures. This assumption would imply that the detection or segmentation of OM or FM textures is accomplished by second-order mechanisms that receive their first-order input from neurons tuned to either the center, or to the peaks in the orientation and spatial-frequency distribution of the texture. Here we show that at low depths of modulation this is not the case. Using an adaptation paradigm, we show that the first-order filters involved in the perception of OM and FM textures are those which maximize the differential response between the different texture regions. Our explanation of this result is similar to that made by Regan and Beverley [J. Opt. Soc. Am. 73 (1983) 1684; J. Opt. Soc. Am. A 2 (1985) 147] for simple grating stimuli. However, we show that whereas Regan and Beverley's results could be accounted for on the basis of the tuning functions of the putative mechanisms involved, our results can be explained in terms of the characteristics of the textures themselves. Some implications of our finding are discussed.

Adaptation, Ocular↗
PubMed1990

Limitations on the parallel guidance of visual search: color x color and orientation x orientation conjunctions.

In visual search for a conjunction it is much more difficult to search for the conjunction of 2 colors or 2 orientations than for Color x Orientation or Color x Shape conjunctions. The result is not limited to particular colors or shapes. Two colors cannot occupy the same spatial location in Color x Color searches. However, Experiments 6 and 7 show that Color x Shape searches remain efficient even if the color and shape are spatially separated. Our guided search model suggests that in searches for Color x Shape, a parallel color module can guide attention toward the correct color, whereas the shape module guides attention toward the correct shape. Together these 2 sources of guidance lead attention to the target. However, if a target is red and green among red-blue and green-blue distractors, it is not possible to guide search independently toward red items and green items or away from all blue items.

Adult↗
PubMed2004

Control of gravitropic orientation. I. Non-vertical orientation by primary roots of maize results from decay of competence for orthogravitropic induction.

Plant organs may respond to gravity by vertical (orthogravitropic), oblique (plagiogravitropic) or horizontal (diagravitropic) growth. Primary roots of maize (Zea mays L.) provide a good system for studying such behaviours because they are reportedly capable of displaying all three responses. In current work using maize seedlings of the Silver Queen cultivar, stabilisation of growth at an oblique orientation was commonplace. Hypothetically, plagiogravitropism may be accomplished either by a process we call graded orthogravitropism or by hunting about a sensed non-vertical setpoint. In graded orthotropism primary bending is unidirectional and depends on facilitative stimuli that determine its extent. The hallmark of the setpoint mechanism is restorative curvature of either sign following a displacement; both diagravitropism and orthogravitropism are based on setpoints. Roots settled in a plagiogravitropic orientation were tested with various illumination and displacement protocols designed to distinguish between these two hypotheses. The tests refuted the setpoint hypothesis and supported that of graded orthotropism. No evidence of diagravitropism could be found, thus, earlier claims were likely based on inadequately controlled observations of graded orthotropism. We propose that orthotropism is graded by the sequential action of dual gravity receptors: induction of a vectorial gravitropic response requires gravitational induction of a separate facilitative response, whose decay in the absence of fresh stimuli can brake gravitropism at plagiotropic angles.

Darkness↗
PubMed2002

Perceived orientation in physical and virtual environments: changes in perceived orientation as a function of idiothetic information available.

Two experiments examined perceived spatial orientation in a small environment as a function of experiencing that environment under three conditions: real-world, desktop-display (DD), and head-mounted display (HMD). Across the three conditions, participants acquired two targets located on a perimeter surrounding them, and attempted to remember the relative locations of the targets. Subsequently, participants were tested on how accurately and consistently they could point in the remembered direction of a previously seen target. Results showed that participants were significantly more consistent in the real-world and HMD conditions than in the DD condition. Further, it is shown that the advantages observed in the HMD and real-world conditions were not simply due to nonspatial response strategies. These results suggest that the additional idiothetic information afforded in the real-world and HMD conditions is useful for orientation purposes in our presented task domain. Our results are relevant to interface design issues concerning tasks that require spatial search, navigation, and visualization.

Adolescent↗
PubMed1984

Effects of intertrial interval, orientation, and adaptation on orientation discrimination measured with a yes-no signal detection paradigm.

Orientation discriminations were measured with a 3.8-cpd sinusoidal grating stimulus and a yes-no signal-detection procedure. Analysis showed that such discriminations are independent of light-adaptation conditions and of intertrial interval over the 2- to 8-sec. range of values explored. However, they are strongly influenced by the orientation where measurements are made (the "oblique effect").

Adaptation, Ocular↗