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PubMed1981

A comparison of interpersonal distancing behavior in young and elderly adults.

Differences in cortical activation (arousal), age, and race were used to test several hypotheses on interpersonal distancing behaviors which have implications for intergenerational and cross-cultural interaction. The investigation centered on the relationship of sensory deficits in the elderly to their use of personal space in peer interactions. A comparison of young, white female college students and elderly white females indicated no significant differences in arousal level, but the younger adults used significantly closer distancing behaviors with their peers. However, a similar comparison of elderly white and black females revealed no differences in either arousal level or interpersonal distancing. The findings suggest that interpersonal distancing behaviors may be less influenced by the need for cortical stimulation than by the prevalence of cultural norms. It also suggests that the proxemic behavior of adult college students may be more adolescent than adult in its personal space scheme.

Adult↗
PubMed1990

Solution structure of neurotoxin I from the sea anemone Stichodactyla helianthus. A nuclear magnetic resonance, distance geometry, and restrained molecular dynamics study.

The three-dimensional structure of the sea anemone polypeptide Stichodactyla helianthus neurotoxin I in aqueous solution has been determined using distance geometry and restrained molecular dynamics simulations based on NMR data acquired at 500 MHz. A set of 470 nuclear Overhauser enhancement values was measured, of which 216 were used as distance restraints in the structure determination along with 15 dihedral angles derived from coupling constants. After restrained molecular dynamics refinement, the eight structures that best fit the input data form a closely related family. They describe a structure that consists of a core of twisted, four-stranded, antiparallel beta-sheet encompassing residues 1-3, 19-24, 29-34, and 40-47, joined by three loops, two of which are well defined by the NMR data. The third loop, encompassing residues 7-16, is poorly defined by the data and is assumed to undergo conformational averaging in solution. Pairwise root mean square displacement values for the backbone heavy atoms of the eight best structures are 1.3 +/- 0.2A when the poorly defined loop is excluded and 3.6 +/- 1.0A for all backbone atoms. Refinement using restrained molecular dynamics improved the quality of the structures generated by distance geometry calculations with respect to the number of nuclear Overhauser enhancements violated, the size of the total distance violations and the total potential energies of the structures. The family of structures for S. heliathus neurotoxin I is compared with structures of related sea anemone proteins that also bind to the voltage-gated sodium channel.

Amino Acid Sequence↗
PubMed1987

The widened teardrop distance: a plain film indicator of hip joint effusion in adults.

The teardrop distance is defined as the distance from the lateral margin of the pelvic teardrop to the most medial aspect of the femoral head as seen on anteroposterior pelvic radiographs. The structure responsible for the teardrop is the anteroinferior portion of the acetabular fossa with contributions from the ischium and from the superior pubic ramus. Anteroposterior pelvic radiographs of 10 patients with documented cases of unilateral hip effusion were retrospectively evaluated for teardrop distance widening on the affected side. Proof of the presence of hip effusion was based on the results of percutaneous hip joint aspirations as described in the patient's medical records. A teardrop distance widening of 1 mm or more was always consistent with hip joint fluid. In addition, radiographs from 20 patients with no known hip abnormalities were reviewed as a control population. These showed side-to-side symmetry in 16 cases (80%) and widening of less than 1 mm in the remaining four cases (20%). Thus, hip joint effusion in adults can be accurately diagnosed from plain radiographs in the presence of a teardrop asymmetry of 1 mm or more and in the absence of degenerative joint disease.

Adolescent↗
PubMed2006

Shear bond strength with increasing light-guide distance from dentin.

BACKGROUND: In Class II composite restorations, the adhesive covering the gingival floor of the deep cavity preparation is 2 to 8 mm from the light guide and may not be adequately cured with a typical 10-second curing time. PURPOSE: The purpose of this study was to evaluate the dentin bond strengths of resin composite when the curing light guide (quartz-tungsten-halogen light) was placed at various distances and to investigate the relationships between radiant exposure, degree of conversion, and shear bond strength. MATERIALS AND METHODS: Single Bond (3M ESPE, St. Paul, MN, USA) was placed onto the dentin following the manufacturer's directions. Four groups of 10 teeth were cured for 20 seconds through a 0, 2.3, 4.6, or 6.9 mm spacer. Two other groups of 10 teeth were cured through a 4.6 mm spacer for 40 seconds and 60 seconds, respectively. Z100 resin composite (3M ESPE) was placed over the cured adhesive and polymerized at the same distance as the adhesive. After 24 hours of storage in water, the shear bond strengths were tested. The irradiance through each spacer was measured using a digital radiometer. The degree of conversion of the adhesive was determined by near infrared spectroscopy. The data were analyzed using analysis of variance and Tukey-B post hoc tests. RESULTS: Dentin shear bond strengths decreased significantly with increasing distance, but they increased significantly when the curing time increased from 20 to 40 or 60 seconds. There is a linear correlation between shear bond strength, degree of conversion, and logarithm (radiant exposure). CONCLUSION: Increasing curing time can compensate for the decreased bond strength owing to a decreased irradiance associated with increased curing distance. CLINICAL SIGNIFICANCE: Under the conditions of this study, when curing the adhesives in deep proximal boxes with a quartz-tungsten-halogen light, the curing time should be increased to 40 to 60 seconds to ensure optimal polymerization.

Analysis of Variance↗
PubMed1985

Effects of subject-to-experimenter distance and instructions on lateral eye movement.

Lateral eye movements and heart rate were recorded as 32 right-handed men answered verbal and spatial questions. Experimenter-to-subject distance (.8 and 1.5 m) and attention demand of instructions were manipulated in a 2 X 2 design. A significant main effect for distance and an interaction of distance by instructions appeared on the direction of eye movements independent of type of question. The greatest number of leftward eye movements occurred at the short distance with instructions demanding higher attention. These findings are consistent with evidence that emotional arousal produces greater right- than left-hemisphere activation.

Anxiety↗
PubMed1997

Visible-light curing units: correlation between depth of cure and distance between exit window and resin surface.

Study 1) The depth of proximal cavities was measured on previously taken bitewing radiographs. Study 2) By means of a scrape test, the relationship between depth of cure and irradiation distance was examined with four different curing units and two different restorative resins. Study 3) The microhardness of one of the polymerized resins was measured 0.5 mm below the free surface of the filling and then at 1.0 mm, 1.5 mm, 2.0 mm, and so forth until the resin became so soft that no hardness could be recorded. The hardness at each 0.5-mm level was recorded in relation to irradiation distance. 1) The cavity depth was most often 4-5 mm in lower premolars, 5 6 mm in upper premolars and lower molars, and 5-7 mm in upper molars. In the latter teeth, 15% of the cavities were > or =8 mm deep. 2 and 3) The depth of cure decreased moderately and in a linear manner with increasing irradiation distance. An irradiation distance of 12 mm reduced the depth of well-cured resin only by about 1 mm as compared with close contact between exit window and surface of resin.

Adult↗
PubMed2003

The effect of semantic distance in yes/no and go/no-go semantic categorization tasks.

The effect of semantic distance (Lund & Burgess, 1996) was examined in three semantic categorization experiments. Experiment 1, a yes/no task that required participants to make animal/nonanimal judgments by responding to both sets of stimuli (Forster & Shen, 1996), revealed no effect of semantic distance. Experiment 2, a go/no-go task that required participants to respond to only the experimental (i.e., nonanimal) items, revealed a large effect of semantic distance. In addition, response latencies were longer and error rates were lower to the experimental items in Experiment 2 than to those in Experiment 1. These findings were replicated in Experiment 3, in which semantic distance and task condition were manipulated within subjects. We conclude that these results are consistent with (1) the view that the go/no-go tasks elicited more extensive processing of the experimental items and (2) a connectionist account of semantic activation, whereby processing is facilitated by the presence of semantic neighbors.

Humans↗
PubMedDate not supplied

Distance stereo acuity improvement in intermittent exotropic patients following strabismus surgery.

To determine whether distance stereo acuity improved following strabismus surgery in patients with intermittent exotropia, we tested 20 patients (5 to 87 years old) preoperatively and postoperatively using the Mentor BVAT II Video acuity tester (Santa Barbara, Calif) and binocular visual system. Acuity improved in 75% as assessed by contour circles and in 45% as assessed by random dot E tests at distance. Our results suggest that surgical realignment of intermittent exotropia restores distance stereo acuity. We conclude that measuring distance stereo acuity offers valuable information in the evaluation of the intermittent exotropic patient.

Adolescent↗
PubMed2003

Normal values of knee angle, intercondylar and intermalleolar distances in Nigerian children.

There is little data on the range of variation of knee angle, intermalleolar and intercondylar distances in African children. Such measurements are needed to assist determining whether a child legs are normal or not. Knee angle intermalleolar and intercondylar distances were measured in 2166 Nigerian children aged one year to 10 years to establish normal values for these measurements. In the study we discovered that knees were maximally bowed at ages 1-3 years and reduced to neutral of 0 degrees at age five (5 years) in girls and age seven (7) in boys. Both sexes had no bowing after age (7 years) in boys. Both sexes had no bowing after age of 7 years. The valgus angle was found to be constant at about 11 degrees between ages 1-10 years in both sexes. Mean intercondylar distance was 0.2 cm at 1 year of age and did not vary significantly at 10 years of age. The greatest intermalleolar distances of 2.5 cm and 2.2 cm were noted between the ages of 2 and 4 years. Normograms of these measurements are presented as diagnostic aids in clinical settings.

Anthropometry↗
PubMed1988

[Effects of liking, interpersonal distance, and topics on nonverbal behaviors].

Effects of liking, interpersonal distance, and intimacy of topics on nonverbal behaviors were investigated in a setting simulating natural interaction, using a multichannel approach, which simultaneously took account of look, eye contact, body orientation, body lean, head orientation, and utterances. Twenty four male undergraduates interacted in pairs. Their interactions were video-taped. 1. Effects of liking were found on forward body lean, smile, head orientation, eye contact, and quantity of look. 2. Effects of interpersonal distance were found on forward body lean, eye contact, and body orientation. 3. In high liking, the smaller the interpersonal distance (or the greater the immediacy in terms of interpersonal distance), the greater the immediacy defined as a composite of other behaviors, and in low liking vice versa.

Adult↗
PubMed2001

[The relationship between the categorical perception of facial expressions and semantic distances].

It has been argued whether the facial expression is recognized categorically or dimensionally. We investigated this issue using three sets of morphed photographic facial images (happiness to anger, surprise, and sadness). Our interest is whether the experimental data of categorical perception can be explained by the dimensional point of view. Experiment 1 examined the facial stimuli generated by FACS. In Experiment 2, subjects were asked to discriminate some pairs of faces and to categorize the emotion shown one at a time. The discrimination accuracy between categories was better than that within each category. In Experiment 3, subjects were asked to rate those stimuli following the semantic differential technique. Then we examined the relationship between the discrimination accuracy obtained in Experiment 2 and the semantic distances obtained in Experiment 3, defined by Euclidean distances between pairs of stimuli in the factor space that was constituted two factors interpreted as "pleasantness" and "activities". Discrimination accuracy within each category increased as a function of the semantic distances, whereas discrimination accuracy between categories remained high irrespective of the different semantic distances.

Adolescent↗
PubMed2006

Comparing self-reported burnout of pharmacy students on the founding campus with those at distance campuses.

OBJECTIVES: To compare burnout among students: (1) assigned to the founding campus and those assigned to distance campuses and (2) in different academic years of the curriculum. The third objective was to determine the relative ability of each factor to predict burnout among pharmacy students. METHODS: Students in Gainesville (founding campus) and the Jacksonville, Orlando, and St. Petersburg distance campuses were surveyed using the Maslach Burnout Inventory. Internet-based survey methods were used to evaluate the emotional exhaustion, personal accomplishment, and depersonalization domains. Students responded using a Likert-type scale (1 = do not feel this way to 7 = feel this extremely strongly). RESULTS: Among 18 items, 8 significant differences were revealed. Within the emotional exhaustion domain, Gainesville students responded that they were more likely to "feel fatigued in the morning" (p < 0.001), "burned out" (p = 0.001), "used up" (p = 0.02), "frustrated" (p = 0.02), and "emotionally drained" (p < 0.02) compared to the distance students. Gainesville students had the highest average score on the item "I feel as though I treat my student colleagues impersonally" (p = 0.02). Academic year was the best predictor of burnout. Campus assignment was significant for emotional exhaustion, with the highest levels occurring on the founding campus. CONCLUSIONS: With few exceptions, students at the founding campus in Gainesville reported more emotional burnout than students attending classes at the distance campuses.

Adult↗
PubMed1995

Distance and volume measurement using three-dimensional ultrasonography.

The purpose of this study was to assess the accuracy of distance and volume measurements obtained by three-dimensional ultrasonography. A tissue-mimicking phantom was scanned using a prototype three-dimensional sonographic imaging system to verify distance measurements. Measurements were taken from the reconstructed three-dimensional sonographic data and compared to the real distances. Volume measurements were obtained by scanning 30 balloons of various shapes, sized 23 ml to 2400 ml. Each balloon was scanned twice in two orientations; three different masks were accomplished for each volume. Each volume measurement of 180 three-dimensional sonographic measurements was compared to conventional two-dimensional ultrasonographic volume estimates and to the actual, measured balloon size. Distance measurements had a mean error of 0.02 +/- 3.65% (range, -4.27 to 7.18%). Two-dimensional sonographic volume estimates using traditional scanner based methods had a mean error of 13.7 +/- 10.1%. Three-dimensional sonographic volume measurements had a mean error of 2.2 +/- 2.9% for regular and irregular objects over the entire range of volumes. The masking required 10 to 30 min. The field of view varied from 10 to 24 cm with a mean object depth of 9.8 cm. Three-dimensional ultrasonographic methods can provide accurate volume measurements of regular and irregular objects and offer improved accuracy compared to traditional two-dimensional methods.

Equipment Design↗
PubMed1999

Long-distance PCR-based screening for large rearrangements of the LDL receptor gene in Korean patients with familial hypercholesterolemia.

BACKGROUND: The LDL receptor is a cell-surface protein that regulates plasma cholesterol by specific uptake of LDL particles from the blood circulation. Familial hypercholesterolemia (FH) results from defective catabolism of LDL, which is caused by mutations in the LDL-receptor gene. METHODS: For the rapid and reliable detection of large rearrangements in the LDL-receptor gene, we established a screening method based on long-distance PCR as an alternative to Southern-blot hybridization. Using long-distance PCR, 45 unrelated Korean subjects heterozygous for FH were screened to assess the frequency and nature of major structural rearrangements in the LDL-receptor gene. RESULTS: Two different deletion mutations, FH6 (same type as FH3 and FH311) and FH 32, were detected in four families by long-distance PCR. Detailed restriction mapping and sequence analysis showed that FH6 was a 5.71-kb deletion extending from intron 8 to intron 12 and that FH32 was a 2-kb deletion extending from intron 6 to intron 7. Sequence analysis for the breakpoints of all deletions detected in Korean FH patients showed that only the left arms of the Alu repetitive sequences were involved in the deletion event. CONCLUSIONS: The screening method based on long-distance PCR provides a powerful strategy for the detection of large rearrangements in the LDL-receptor gene and is a rapid and reliable screening alternative to Southern-blot hybridization.

Base Sequence↗
PubMed2000

Prevalence of usual-corrected binocular distance visual acuity impairment in Hispanic and non-Hispanic adults.

OBJECTIVES: The purpose of this study was to perform comparative analyses of the population-based prevalence of usual-corrected binocular distance visual acuity impairment among Hispanics and non-Hispanics in the United States. METHODS: Data from the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-1984, and the National Health and Nutrition Examination Augmentation Survey I (NHANES I-A), 1974-1975, were analyzed to investigate the epidemiology of usual-corrected binocular distance acuity in adults 25 to 74 years of age among Cuban-Americans (N=396), Mexican-Americans (N=1,381), Puerto Ricans (N=513), African-Americans (N=250), and non-Hispanic white Americans (N=2, 660). Binocular distance acuity was assessed using Sloan Letters or Landolt Rings with the participants wearing their corrective lenses, if any. RESULTS: Prevalences of 20/50 or worse usual-corrected binocular distance acuity were 3.5%, 4.6%, and 6.6% for Cuban-Americans, Mexican-Americans, and Puerto Ricans, respectively, in the HHANES; and 7.7% and 4.1% for African-Americans and non-Hispanic whites, respectively, in the NHANES I-A. Within the HHANES, after adjustment for gender and age, Puerto Rican adults were found to have a significantly higher prevalence of visual impairment (20/50 or worse) and were significantly less likely to become unimpaired with usual correction than Cuban-American adults. Within the NHANES I-A, African-Americans were found to have a higher prevalence of visual impairment (20/50 or worse) and were significantly less likely to become unimpaired with usual correction than non-Hispanic whites. Higher prevalences of visual impairment (20/50 or worse) were associated with increasing age for all ethnic groups. After controlling for age, odds of usual-corrected visual impairment (20/50 or worse) were significantly higher in women than in men for Cuban-Americans and Mexican-Americans (odds ratios: 4.5 and 2.6, respectively). CONCLUSIONS: The results from this study suggest that compared to other Hispanic groups and non-Hispanic whites, Puerto Rican and African-American adults may not be receiving similar eye care services and/or may have more severe eye diseases.

Adult↗
PubMed2000

Molecular anatomy of BCL6 translocations revealed by long-distance polymerase chain reaction-based assays.

BCL6 translocations involve not only immunoglobulin (IG) genes but also a number of non-IG loci as partners. Junctional sequences of three IG/BCL6 translocations were readily obtained by long-distance PCR. In cases where partner loci were not determined, we developed a long-distance inverse PCR method, which amplifies unknown fragments flanked by known BCL6 sequences. Using these two long-distance PCR-based approaches, we cloned junctional areas of BCL6 translocations from a total of 58 cases of B-cell tumors. Nucleotide sequencing and database searches revealed that 30 cases involved IGs as partners: IG heavy chain gene in 22, IG kappa light chain gene in 1, and IG lambda light chain gene in 7. In contrast, 23 cases affected non-IG loci, including the H4 histone gene, heat shock protein genes HSP89alpha and HSP90beta, and PIM-1 proto-oncogene. On der(3) chromosomes, complete sets of the promoters of these partner genes replaced that of BCL6 in the same transcriptional orientation. These results suggest that BCL6 gene affected by the translocation is transcriptionally activated by a variety of stimuli, including cell cycle control, changes in the physical environment, and response to cytokines. Break points on BCL6 occurred within the major translocation cluster, and we identified a 120-bp hyper-cluster region a short distance from the 3' end of exon 1. Gel mobility-shift assay suggested the presence of a protein(s) that bound to this particular region.

Base Sequence↗
PubMed2000

Managed care, distance traveled, and hospital market definition.

Does managed care insurance require patients to travel farther to receive hospital care? This question has major implications for antitrust policy and access to care. In spite of a general presumption that the answer is "yes," the question cannot be settled by a priori reasoning. Managed care has two effects on distance: 1) the direct effect of steering managed care consumers to particular hospitals, and 2) the indirect effect of higher managed care market share changing the market environment for consumers in general. The net effect of managed care on distance traveled could go either way. This paper measures both direct and indirect effects in a unique application of a spatial interaction model. We use individual discharge data, including payer information, from hospitals in 14 California counties over the period 1984-1993. We find that the direct effect leads to longer distances, but the indirect effect leads to shorter distances. Neither effect is large. Surprisingly, the net effect is slightly negative.

California↗
PubMed2000

Surgical modification of the AC/A ratio and the binocular alignment ("Phoria") at distance; its influence on accommodative esotropia: a study of 21 cases.

PURPOSE: To study these changes in patients and their relation to manifestation of accommodative esotropia and response to surgery. METHODS: Patient-subjects: 21 patients who had difficulty adjusting to spectacle correction and underwent bilateral medial rectus loop suspension-recession surgery to alleviate their accommodative esotropia. Measurements of AC/A, uncorrected distance phoria, and related parameters were taken before and after surgical intervention was performed and were analyzed using analysis of variance (ANOVA). RESULTS: Both AC/A ratios and the distance phorias are "statistically significantly" (p< or =0.05), and independently, reduced by this surgical procedure. The manifestation of accommodative esotropia and response to surgery can be fairly accurately predicted from the values of AC/A ratio and distance phoria. CONCLUSION: Surgical treatment of accommodative esotropia creates well defined, long-lasting reductions in the AC/A ratio and the distance phoria.

Accommodation, Ocular↗