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At least 19 recordsLinked to original sources
PubMed1978

Studies on the orientations of the mitochondrial redox carriers. II. Orientation of the mitochondrial chromophores with respect to the plane of the membrane in hydrated, oriented mitochondrial multilayers.

Orientations of the active site chromophores of the mitochondrial redox carriers have been investigated in hydrated, oriented multilayers of mitochondrial membranes using optical and EPR spectroscopy. The hemes of cytochrome c oxidase, cytochrome c1, and cytochromes b were found to be oriented in a similar manner, with the normal to their heme planes lying approximately in the plane of the mitochondrial membrane. The heme of cytochrome c was either less oriented in general or was oriented at an angle closer to the plane of the mitochondrial membrane than were the hemes of the "tightly bound" mitochondrial cytochromes. EPR spectra of the azide, sulfide and formate complexes of cytochrome c oxidase in mitochondria in situ obtained as a function of the orientation of the applied magnetic field relative to the planes of the membrane multilayers showed that both hemes of the oxidase were oriented in such a way that the angle between the heme normal and the membrane normal was approx. 90 degrees.

Animals↗
PubMed2002

[Client-orientation versus institutional-orientation. What helps towards client-orientation in psychiatric settings?].

Client- or Patient-Orientation is seen as an indicator for quality of psychiatric work. How to observe and record this orientation? Three different concepts are presented: the German A11, a staff- and client-oriented documentation, Soteria Bern, and Shepherd's 25 homes-investigation around London. Four areas of typical conflicts of interest between client- and institutional orientation are presented with examples: duty times, strategies to fill up beds, "creaming off", and application-talks for clients to enter a residential setting. On the basis of the quality of Life and Care research and the 3 concepts above questions for visiting and evaluating homes and living groups and for personal check-ups are presented.

Conflict of Interest↗
PubMed1979

Studies of the orientation of the mitochondrial redox carriers. III. Orientation of the gx and gy axes of the hemes of cytochrome oxidase with respect to the plane of the membrane in oriented membrane multilayers.

The EPR absorption properties of the hemes of cytochrome oxidase and their liganded derivatives were examined in oriented multilayers from isolated oxidase, mitochondrial membranes and membrane fragments of a bacterium, Paracoccus denitrificans. The hemes of the oxidase in all the systems investigated were oriented normal to the plane of the multilayers. The directions of the g signals corresponding to the gx and gy axes of the g tensor were found to be different in low-spin ferric heme in fully oxidized oxidase and in half-reduced liganded oxidase. It is suggested that this different orientation of gx and gy in fully oxidized oxidase and half-reduced liganded oxidase arises because the respective EPR signals belong to two different hemes, those of cytochrome a and a3.

Animals↗
PubMed2001

Comparison of orientation maps obtained with different number of stimulus orientations.

The structure of orientation maps computed from a different number of stimulus orientations was studied in visual cortical area 18 of the cat. Single condition maps (SCMs) were obtained to 16 stimulus orientations, of which angle maps were generated using 4, 8, and 16 SCMs corresponding to multiples of 45, 22.5, and 11.25 degrees, respectively. The overall orientation distribution of the three types of maps was compared on a pixel-by-pixel basis. Twenty percent of the pixels of the 4-orientations maps differed by more than +/-17 degrees from those produced by 16 orientations. Maps of 8 orientations differed by 6.4 and 5.8% from those of 4 and 16 orientations, respectively. Structural differences between the maps were mainly found at locations displaying high rate of change in orientation preference, i.e., orientation centers and adjoining short, fracture-like zones. These changes included lateral shifts up to 155 microm (average: 38.7 microm) in the position of orientation centers and appearance/disappearance of orientation centers when compared between different conditions. In general, these changes were three times more frequent between maps of 4/8 and 4/16 orientations than 8/16 orientations. It is concluded that orientation maps should be calculated from activity maps representing 8 or more stimulus orientations.

Animals↗
PubMed1992

Orientational distribution of spin-labeled actin oriented by flow.

Previous studies on spin-labeled F-actin (MSL-actin), using saturation transfer electron paramagnetic resonance (ST-EPR), have demonstrated that actin has submillisecond rotational flexibility and that this flexibility is affected by the binding of myosin and its subfragments. This rotational flexibility does not change during the active interaction of myosin heads, actin, and adenosine triphosphate. However, these ST-EPR studies, performed on randomly oriented actin, would not be sensitive to orientational changes on the millisecond time scale or slower. In the present study, we have clarified these results by performing conventional EPR experiments on MSL-actin oriented by flow to detect changes in the orientational distribution. We have determined the orientational distribution of the spin labels relative to the magnetic field (flow direction) by comparing experimental EPR spectra to simulated EPR spectra corresponding to known orientational distributions. Spectra acquired during flow indicate two populations of probes: a highly ordered population and a disordered population. For the ordered population (28% of the total spin concentration), the angle between the actin filament axis and the nitroxide z axis (theta) fits a Gaussian distribution centered at 32.0 +/- 0.9 degrees, with a full width at half maximum of 20.7 +/- 3.9 degrees. The angle between the nitroxide x axis and the projection of the field in the xy plane (phi) is centered at 37.5 +/- 9.2 degrees with a full width of 24.9 +/- 10.7 degrees. This orientational distribution is not significantly changed upon the binding of phalloidin or myosin subfragment 1 (S1), indicating that these proteins do not affect the axial orientation of actin subunits. Spectra of spin-labeled S1 (MSL-S1) bound to actin oriented by flow have about the same orientational distribution as MSL-S1 bound to actin in oriented fibers. Thus, the oriented fraction of flow-oriented actin filaments has nearly the same high degree of alignment as the actin filaments in muscle fibers.

Actins↗
PubMed1981

Restriction of visual experience to a single orientation affects the organization of orientation columns in cat visual cortex. A study with deoxyglucose.

In six dark reared, 4-weak-old kittens visual experience was restricted to contours of a single orientation, horizontal or vertical, using cylindrical lenses. Subsequently, the deoxyglucose method was used to determine whether these artificial raising conditions had affected the development of orientation columns in the visual cortex. After application of the deoxyglucose pulse one hemifield was stimulated with vertical, the other with horizontal contours. Thus, from interhemispheric comparison, changes in columnar systems corresponding to experienced and inexperienced orientations could be determined. The following results were obtained: (1) Irrespective of the restrictions in visual experience, orientation columns develop in areas 17, 18, 19 and in the visual areas of the posterior suprasylvian sulcus. (2) Within area 17, spacing between columns encoding the same orientations is remarkably regular (1 mm), is not influenced by selective experience and shows only slight interindividual variation. (3) In non-striate areas the spacing of columns is less regular and the spatial frequency of the periodicity is lower. (4) The modifiability of this columnar pattern by selective experience is small within the granular layer of striate cortex but substantial in non-granular layers: Within layer IV columns whose preference corresponds to the experienced orientation are wider and more active than those encoding the orthogonal orientation but the columnar grid remains basically unaltered. Outside layer IV the columnar system is maintained only for columns encoding the experienced orientations. The deprived columns by contrast frequently fail to extend into non-granular layers and remain confined to the vicinity of layer IV. (5) These modifications in the columnar arrangement are more pronounced in striate cortex than in nonstriate visual areas and, within the former, more conspicuous in the central than in the peripheral representation of the visual field. It is concluded that within layer IV the blue print for the system of orientation columns is determined by genetic instructions: first order cells in layer IV develop orientation selectivity irrespective of experience whereby the preference for a particular orientation is predetermined by the position in the columnar grid. Dependent on experience is, however, the expansion of the columnar system from layer IV into non-granular layers. It is argued that all distortions following selective rearing can be accounted for by competitive interactions between intracortical pathways, the mechanisms being identical to those established for competitive processes in the domain of ocular dominance columns. It is proposed that such experience dependent modifiability of connections between first and second order cells is a necessary prerequisite for the development of orientation selectivity in cells with large and complex receptive fields.

Animals↗
PubMed1995

Orientation contrast vs orientation in line-target detection.

This study concerns the roles of absolute and relative orientation in determining detectability of a line-element target in a background field of uniformly oriented line elements. Target detectability was determined as a function of background-field orientation, sampled at 5 deg intervals, for three levels of orientation contrast--the difference between target and background orientations--sampled at 10, 20 and 30 deg. Stimulus displays were presented briefly and followed by a mask. There were 10 observers, whose detection performance was quantified by the discrimination index d' from signal detection theory. Target detectability was found to depend both on absolute orientation, represented by background-field orientation, and on orientation contrast. At each level of orientation contrast, performance was best when the background field, not the target element, was vertical or horizontal. These data are difficult to explain by general models of orientation discrimination based on simple orientation opponency between local line-sensitive filter units; three other models specifically concerned with target detection are briefly considered.

Adult↗
PubMed2000

Reality orientation for dementia.

BACKGROUND: Reality Orientation (RO) was first described as a technique to improve the quality of life of confused elderly people, although its origins lie in an attempt to rehabilitate severely disturbed war veterans, not in geriatric work. It operates through the presentation of orientation information (eg time, place and person-related) which is thought to provide the person with a greater understanding of their surroundings, possibly resulting in an improved sense of control and self-esteem. There has been criticism of RO in clinical practice, with some fear that it has been applied in a mechanical fashion and has been insensitive to the needs of the individual. There is also a suggestion that constant relearning of material can actually contribute to mood and self-esteem problems. There is often little consistent application of psychological therapies in dementia services, so a systematic review of the available evidence is important in order to identify the effectiveness of the different therapies. Subsequently, guidelines for their use can be made on a sound evidence base. OBJECTIVES: To assess the evidence of effectiveness for the use of Reality Orientation (RO) as a classroom-based therapy on elderly persons with dementia. SEARCH STRATEGY: Computerised databases were searched independently by 2 reviewers entering the terms 'Reality Orientation, dementia, control, trial or study'. Relevant websites were searched and some handsearching was conducted by the reviewer. Specialists in the field were approached for undocumented material, and all publications found were searched for additional references. SELECTION CRITERIA: All randomised controlled trials (RCTs), and all controlled trials with some degree of concealment, blinding or control for bias (second order evidence) of Reality Orientation as an intervention for dementia were included. The criteria for inclusion/exclusion involved systematic assessment of the quality of study design and the risk of bias, using a standard data extraction form. A measure of cognitive and/or behavioural change was needed. DATA COLLECTION AND ANALYSIS: Data were extracted independently by both reviewers, using a previously tested data extraction form. Authors were contacted for data not provided in the papers. Psychological scales measuring cognitive and behavioural changes were examined. MAIN RESULTS: 6 RCTs were entered in the analysis, with a total of 125 subjects (67 in experimental groups, 58 in control groups). Results were divided into 2 subsections: cognition and behaviour. Change in cognitive and behavioural outcomes showed a significant effect in favour of treatment. REVIEWER'S CONCLUSIONS: There is some evidence that RO has benefits on both cognition and behaviour for dementia sufferers. Further research could examine which features of RO are particularly effective. It is unclear how far the benefits of RO extend after the end of treatment, but and it appears that a continued programme may be needed to sustain potential benefits.

Aged↗
PubMed2003

The role of local grouping and global orientation contrast in perception of orientation-modulated textures.

We explored the contribution to perception of orientation-modulated textures of visual processes selective either for orientation contrast or orientation grouping. To distinguish between these two processes we manipulated the axis of local grouping of texture elements independently of the direction of global orientation modulation. The general question posed was whether visibility of texture structure (measured as threshold for discriminating spatial-frequency of texture structure) is dependent on the magnitude of orientation contrast, strength and direction of local grouping, or some combination of the two. We demonstrated that the factor of primary importance is the amplitude of global orientation contrast rather than the presence of local grouping content. Using orientation-interleaved textures (containing two superimposed textures modulated around orthogonal orientations), we further showed that orientation single-opponent processes are a more likely candidate for detecting orientation contrast than double-opponent processes.

Contrast Sensitivity↗
PubMed1988

Predicting talocalcaneal joint orientations from talocalcaneal/talocrural joint orientations.

The purpose of this investigation was to determine the capacity of talocalcaneal/talocrural joint orientations to predict talocalcaneal (TC) joint orientations. A custom designed orientation-loading fixture was used to position the calcaneus and shank with six degrees of freedom, and to apply loads in three orthogonal directions. Three reference pins were rigidly mounted in the calcaneus, talus, and shank segments to provide position data in 243 test situations. Test data were fitted to statistical models using analysis of variance. The models were then used to determine the capacity to predict talus positions from shank positions, both with respect to the calcaneus. Results indicated large between and within specimen variation and was attributed to individual joint morphology. It was concluded that (a) eversion-inversion orientations of the TC/talocrural joint were not always accurate indicators of TC joint orientations, (b) abduction-adduction orientations of the combined joint had the greatest overall influence on TC orientations (thus, monitoring eversion-inversion and abduction-adduction orientations of the combined joint would be more valuable in predicting pronation-supination positions than monitoring only eversion-inversion orientations), and (c) foot categories based on TC and TC/talocrural joint morphology should be developed. They would provide more accurate prediction for specimen foot orientations than prediction from overall average values.

Adult↗
PubMed1996

Magnetically orientated tissue-equivalent tubes: application to a circumferentially orientated media-equivalent.

Circumferential orientation of collagen fibrils in a media-equivalent (ME) is achieved in a simple and effective way using the orientating effects of a strong magnetic field during collagen fibrillogenesis when the ME is first created. Circumferential orientation of the entrapped smooth muscle cells (SMC) is achieved subsequently via cell contact guidance, the induced SMC orientation along orientated fibrils. After describing the methods used, several lines of evidence are provided showing that the magnetically orientated ME is circumferentially orientated, including collagen birefringence, circumferential SMC orientation, accelerated ME compaction and increased ME stiffness with reduced creep in the circumferential direction as compared to control MEs not exposed to a magnetic field during fibrillogenesis. The optimization of these methods is discussed in order to better mimic the circumferential orientation and mechanical properties of a natural medium. Other applications of magnetically orientated tissue-equivalents are indicated.

Animals↗
PubMed2000

Parallel detection of orientation differences in the presence of orientation gradients.

We measured thresholds and reaction times for detecting a target, defined by orientation contrast, as a function of the number of elements displayed simultaneously and of the linear orientation gradient present in the display. This test served to evaluate how well the human visual system is able to ignore smooth gradients in orientation - similar to what it does with gradients of luminance or wavelength. Smooth orientation gradients are common in natural environments as opposed to the usual laboratory (search) experiments. It turns out that targets defined by a discontinuity in the transition between line orientations can be processed in parallel, i. e. that 'search' times increase by between 0.5 and 6 ms, on average, per additional element displayed, irrespective of the number of elements. But thresholds of orientation difference for the detection of the target increase linearly with the orientation gradient present in the display, and tend to increase more strongly for small gradients, indicating a special bonus for (near) collinearity. The averaged data follow a Weber-law type while this is not true for the individual observers' data. These results show that the visual system is indeed able to detect targets based on orientation contrast, rather than on absolute orientation [cf. Nothdurft (1985). Vision Research, 25, 551-560], but that the orientation gradient cannot be ignored.

Computer Graphics↗
PubMed2000

Three dimensional laser scan assessment of the Oriental nose with a new classification of Oriental nasal types.

The Oriental nose, which has been broadly classified as mesorrhine, differs in anatomy and morphology from other racial groups. The objective of this study is to carry out anthropometric measurements in the nose region, in order to establish norms for the Oriental nose and also to identify the variations that might occur within this group. Knowledge of the unique shape, anatomy and dimensions of the Oriental nose would be very useful for surgeons undertaking repair and reconstruction of Oriental noses. Ninety, normal Oriental subjects were scanned using a laser surface scanner, and the assessments were then carried out on the laser scan images. The 3-D laser scan images permit adjustment and positioning to achieve the correct standard views for assessment. Subjective assessment of the nose shape, as well as linear and angular measurements were carried out. Depending on the fullness and roundness of the nasal tip and the prominence of the alar lobules on either side, the Oriental nasal base may take on varied shapes and accordingly, three distinct shapes have been identified. They have been classified into types A, B and C where type A has a very prominent alar lobule and a full and rounded nasal tip. In type B, the alar lobule was less prominent and the nasal tip was more defined while in type C the alar lobule was the least prominent resulting in the lateral walls forming a relatively straight slope from the tip to the alar base. The linear and angular measurements for Oriental noses were also obtained and compared to values for other racial groups. The proportion indices for the Oriental nose showed that it was broader in relation to the nose height, and had less tip protrusion in relation to both the height and width of the nose. The data collected from this study can be used as norms for Oriental cases and the simple classification of the nose shape will serve as a guide for quick reference, when planning aesthetic or reconstructive rhinoplasties for the Oriental patient.

Adult↗
PubMed1998

The perception and prehension of objects oriented in the depth plane. II. Dissociated orientation functions in normal subjects.

Normal human subjects were tested for their ability to discriminate the orientation of a square plaque tilted in depth, using two different tasks: a grasping task and a perceptual matching task. Both tasks were given under separate monocular and binocular conditions. Accuracy of performance was measured by use of an opto-electronic motion analysis system, which computed the hand orientation (specifically, a line joining the tips of the thumb and index finger) as the hand either approached the target during grasping or was used to match the target. In all cases there was a very strong statistical coupling between hand orientation and target orientation, irrespective of viewing conditions. However, the matching data differed from the grasping data in showing a consistent curvature in the hand-target relationship, whereby the rate of change of hand orientation as a function of object orientation was smaller for oblique orientations than for those near the horizontal or vertical. The results are interpreted as reflecting the operation of two different mechanisms for analysing orientation in depth: a visuomotor system (assumed to be located primarily in the dorsal cortical visual stream) and a perceptual system (assumed to be located in the ventral stream). It may be that the requirements of visuomotor control dictate a primary need for absolute orientation coding, whereas those of perception dictate a need for more categorical coding.

Adult↗
PubMed2002

Orientation specificity of contrast adaptation in visual cortical pinwheel centres and iso-orientation domains.

Exposure to a high-contrast visual stimulus causes adaptation, a psychophysical phenomenon that is quite selective for stimulus orientation. Its mechanism is largely cortical but the underlying circuitry is still not unambiguously resolved. It has been suggested that adaptation could be the result of integration of inputs from cells within a large local pool, effectively scaling their outputs with respect to local contrast. In this case, orientation selectivity of neuronal adaptation should depend on the location of neurons within the cortical map of orientation preference. We tested this hypothesis by quantifying adaptation to optimally oriented and to orthogonal-to-optimum gratings among neurons recorded either from iso-orientation domains or orientation pinwheel centres, as identified by optical imaging of cat visual cortex. We did not find a significant difference in adaptation characteristics for these two populations of cells, implying that these characteristics do not depend on the local functional architecture. Surprisingly, however, we additionally observed that under isoflurane (but not halothane) anaesthesia, most neurons exhibited adaptation by cross-oriented gratings, regardless of their location within the orientation map. It seems likely that, under isoflurane, inputs became visible that were masked by the commonly used, deeper halothane anaesthesia. For individual cells, the presence of these inputs was independent of their location within the cortical orientation map.

Action Potentials↗
PubMed1991

Orientation in birds. Magnetic orientation and celestial cues in migratory orientation.

Young birds on their first migration possess innate information on the direction of their migration route. It is represented twice, using both celestial rotation and the geomagnetic field as references. These two systems, together with information provided by factors associated with sunset, interact in a complex way to establish the migratory direction. During ontogeny, celestial rotation appears to be dominant; during migration, however, celestial cues appear to be controlled by the magnetic field.--The factors associated with sunset--the view of the setting sun and the characteristic pattern of polarized light--are important secondary cues which seem to derive their directional significance from the magnetic field. Their role appears to be more variable, with possible species-specific differences. During spring migration and later autumn migrations, flying in the migratory direction is complemented by navigational processes which enable the birds to return to a specific home site known from previous stays.

Animals↗
PubMed1998

[Unification of Oriental and Western medicine with study on Oriental and Western medicine].

In Korea the system of medical management has been bifurcated into two parts since the restoration of nation from Japanese after World War II. One is 'Western Medicine' and the other is 'Oriental Medicine' like Chinese but not like Japanese. The authors attempted to study on the unification of both medicines to prevent the confusion of medicare for people. The major part of medical care is accomplished by Western medicine among people in Korea and China. However, Oriental medicine is still present as well as college of Oriental medicine in small number. There have been long struggles between two parts of medicine because of each assertions for the theories. The ancient medicine has been likely to have its characteristics either in Western or Oriental medicine although in many countries were succeeded by Western medicine except a few Asian countries such as Korea and China. In Japan since the license of Oriental(herb) medicine was ceased about one hundred years ago, the Western medicine has been authorized by law until today and the herb is the secondary medicine as a kind of folk treatment as well as continuous and enormous study for scientification. In only China and Korea this herb medicine has been kept to use as a part of medicine by law though China has developed combined medicine to use both Western and Oriental medicine by one physician since previous prime minister Chou En-Lai around the year 1950 who made a recommendation to the two medical societies, Western and Oriental. This fact has a big sense to establish the unification of two medicines in near future in Korea as well as China. For this accomplishment of medical unification both parts of medicine require sincere and enormous efforts to study the theory and practice of herb medicine even from now on. This unification of two medicines will provide the best medicare in most convenient way to the people in the world creating new world medicine like the third medicine including alternative medicine. The acupuncture is changing to a new method in Western medicine especially applying into anesthesia and pain clinic in even USA and Western countries at this time. In conclusion the unification of the Western and Oriental medicine will provide the most reasonable and practical medicare including alternative medicine to people in the world. Because the Oriental medicine will be used at least separately to supplement the Western medicine by one physician.

Asia↗