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PubMed1993

Three-compartment wrist arthrography: correlation of pain site with location of uni- and bidirectional communications.

OBJECTIVE: Our objective was twofold: (1) to determine whether the site of patients' pain correlates with abnormal findings on three-compartment wrist arthrograms and (2) to determine whether the directional nature (uni- vs bidirectional) of communication(s) between adjacent wrist joint compartments shown on three-compartment wrist arthrograms correlates with the presence and site of pain. MATERIALS AND METHODS: We retrospectively studied 462 three-compartment wrist arthrograms of 458 patients. The patients were divided into four groups according to the site of pain, the correlation of that site with the site of the communication, and the directional characteristics of communications shown on the arthrogram: (1) exact correlation between site of pain and arthrographic findings, (2) correlation only between side of pain (ulnar or radial) and arthrographic findings, (3) ambiguous correlations (e.g., multifocal, midline, or diffuse pain), and (4) no correlation between site of pain and arthrographic findings. RESULTS: In 191 patients (42%), 226 intercompartmental communications were detected (51 uni- or 173 bidirectional). One hundred sixty-one patients had only one communication (uni- or bidirectional), and 30 patients had more than one (uni- and/or bidirectional) communication for a total of 65 defects. Regardless of the directional nature of the communication, no positive association between sites and/or the side of symptoms and sites of communications was demonstrable. However, a potential association appears to exist between ulnar-sided pain and combined lunotriquetral and triangular fibrocartilage tears. CONCLUSION: Our results suggest that the directional nature of interjoint communications has little or no clinical significance. Thus, with the exception of seeking the cause of ulnar-sided pain, our results question the usefulness of routine arthrography for correlating sites of patients' symptoms and individual interjoint communications.

Adolescent↗

PubMedDate not supplied

[Correlation between the survival duration and trauma severity in persons who died from posttraumatic fat embolism].

INTRODUCTION: Posttraumatic fat embolism follows the injury. The fat emboli in circulation could cause death in three ways: isolated lung fat embolism, systemic fat embolism and fat embolism syndrome (FES). In forensic pathology, only two trauma scores, based on disintegration of anatomic structures, could be used for objectivization, comparison and establishment of severity of injuries. One of them is Injury Severity Score--ISS, based on Abbreviated Injury Scale--AIS. The second one is Hannover Polytrauma Score--HPTS, based on the total sum of all injuries and age of the injured person. OBJECTIVE: The objectives of this paper were to establish the correlation between outliving period and trauma severity (based on ISS and HPTS values), in persons died from posttraumatic fat embolism and/or its complications, and to establish which of these score systems could be better for prediction of development of the posttraumatic fat embolism. METHOD: The retrospective autopsy study was performed and it included the material of the Institute of Forensic Medicine in Belgrade for period 1988-2001. The autopsy reports and clinical medical data were analyzed, for persons died from posttraumatic fat embolism and/or its complications. In all cases, the fat embolism was the single cause of death, verified by autopsy. In each case, ISS and HPTS values were obtained. The sample was statistically prepared (chi2 test, correlation coefficient, regression line). RESULTS AND DISCUSSION: The sample included 50 persons: 41 males and 9 females. The proportion of men was statistically significant (chi2 = 20.480; p < 0.001). Average age of male was 55.26 years (SD = 21.39) and of female was 55.78 (SD = 17.45). There was no statistically significant disproportion among the age distribution of the sample (chi2 = 6.4; p > 0.05). The outliving period varied from 1-14 days: the average was 5.92 (SD = 3.39; Med. 5.50; Mod. 2). The average value of 1SS was 19 (SD = 7.70; Med. 19; Mod. 14), and for HPTS average value was 28.16 (SD = 12.87; Med. 26.50; Mod. 12). In literature, there have been data about critical ISS value: 12-20. HPTS value of 20 to 35 was lethal in 25%. Each injured of our sample had, at least, one long bone or pelvic fracture. There was negligible negative correlation between outliving period and 1SS and HPTS values in our sample: coefficient of linear correlation r = -0.117, t = 0.83 and r = -0.088, t = 0.59. Our sample was representative (t = 8.37). These data pointed out that the outliving period of the observed patients, died from post-traumatic fat embolism, was not in relation to general severity of injuries but to fat embolism per se and its consequences. There was low positive correlation between ISS and HPTS values: r = 0.296, t = 2.147, coefficient of determination r2 = 0.0876 and linear regression HPTS = 18.7588+0.4948 ISS. These data indicated that direct correlation between scores was only about 9% and the rest of correlation i.e. 91% depended on other factors. CONCLUSION: There was negative negligible correlation between outliving period and severity of injury based on ISS and HPTS, in patients died from posttraumatic fat embolism. So, these score systems are useless for prediction of duration of the outliving period in the injured died from fat embolism as well as for prediction of posttraumatic fat embolism as cause of death.

Embolism, Fat↗

PubMed1998

Correlation of lethal doses of industrial chemicals between oral or intraperitoneal administration and inhalation exposure.

Correlations of lethal doses of industrial chemicals between oral or intraperitoneal administration and inhalation exposure in rats and mice were investigated. LC50 values for inhalation exposure and LD50 values for oral and intraperitoneal administration were obtained from the Registry of Toxic Effects of Chemical Substances. LC50 and LD50 values were plotted on ordinate and abscissa, respectively, using logarithmic scales. A correlation coefficient of r = 0.624 (n = 146, p < 0.001) was obtained for LC50 (ppm) and LD50 (mg/kg) values with oral administration (oral LD50) in rats. This correlation was improved by converting the units of LC50 from ppm to ppm h (cumulative dose), and by converting the units of LD50 from mg/kg to mmol/kg. The correlation coefficient was r = 0.742 when ppm*hr and mmol/kg were adopted for LC50 and LD50, respectively. A similar improvement in correlation coefficients by the same unit conversion was also observed between LC50 and LD50 with intraperitoneal (i.p.) administration (i.p. LD50) in rats. Correlations between LC50 and oral LD50 in mice were also improved by the same unit conversion. The correlations between LC50 and i.p. LD50 were higher than those between LC50 and oral LD50 both in rats and mice. In these correlations, coefficients obtained in rats were greater than corresponding coefficients in mice. We calculated equations to estimate LC50 values accompanied by confidence limits from oral or i.p. LD50 values.

Administration, Oral↗

PubMed1990

Correlated responses in body composition based on selection for different indicator traits in mice.

Correlated responses in whole-body composition were determined in 12-wk-old male mice from replicate lines selected for 12 generations for high (HF) or low (LF) epididymal fat pad weight as a percentage of body weight (EPID) and high (HL) or low (LL) hind carcass weight as a percentage of body weight. The HF and LF lines diverged (P less than .01) in body fat percentage (FAT) and subcutaneous depot fat by 93 and 71%, respectively, of the control line (RC) mean. EPID increased (P less than .01) proportionately more than FAT in the HF line; EPID decreased (P less than .01) proportionately less than FAT in LF. Protein, fat and water as a percentage of empty body weight showed negative correlated responses (P less than .01) due to selection for EPID, but lean body mass, body weight and body length had positive correlated responses (P less than .01). Correlated responses of fat-free protein and ash percentage were minor. Correlated responses in HL and LL were the mirror images of those in HF and LF, but they generally were of smaller magnitude. The results indicate that, although there are high positive genetic correlations between fat depots in mice, local control of lipogenesis and(or) lipolysis exists at different sites of fat deposition. Further, the lack of correlated responses in fat-free percentage of protein (and percentage of ash) suggests that additive genetic variances are low for these traits and(or) the genetic correlations of these traits with the selection criteria are low.

Adipose Tissue↗

PubMed2002

Correlations among selected pork quality traits.

Establishing relationships among specific quality traits is important if significant progress toward developing improved pork quality is to be realized. As part of a study to examine the individual effects of genes on meat quality traits in pigs, a three-generation resource family was developed. Two Berkshire sires and nine Yorkshire dams were used to produce nine F1 litters. Sixty-five matings were made from the F1 litters to produce four sets of F2 offspring, for a total of 525 F2 animals used in the study. These F2 animals were slaughtered at a commercial facility upon reaching approximately 110 kg. Carcass composition traits, pH measurements, and subjective quality scores were made at 24 h postmortem. Loin samples (n = 525) were collected at 48 h postmortem, and meat quality traits were evaluated. These traits included pH (48 h), Hunter L-values, drip loss, glycolytic potential, ratio of type IIa/IIb myosin heavy chains (IIa/IIb), total lipid, instrumental measures of tenderness using the Star Probe attachment of the Instron, cook loss measurements, and sensory evaluations. Significant phenotypic correlations were found between many carcass, instrumental, and biochemical measurements, and sensory quality traits. Star Probe measurements were significantly correlated with drip loss (0.29), glycolytic potential (0.30), pH (-0.29), total lipid (-0.14), and Hunter L-values (0.28). Drip loss was significantly correlated with glycolytic potential (0.36), pH (-0.28), IIa/IIb (-0.10), and Hunter L-values (0.33). Hunter L-values were also significantly correlated with total lipid (0.33) and IIa/ IIb (-0.11). Sensory tenderness, flavor, and off-flavor scores were significantly correlated with drip loss, pH, and glycolytic potential measurements. Marbling score, total lipid, and drip loss were not significantly correlated with sensory juiciness scores, but cooking loss was. Marbling and total lipid were significantly correlated with firmness scores (0.37 and 0.31, respectively). Taken together, the data in this study suggest that changes in some meat quality traits can affect many other meat quality attributes. The correlations yield information that could aid in directing future studies aimed at understanding the underlying biological mechanisms behind the development of many quality traits.

Animals↗

PubMed2004

Genetic correlations between reproduction and production traits in swine.

Genetic correlations between reproduction and production traits were estimated in swine. Reproduction traits investigated were age at first service (AFS), number of live-born piglets in the first litter (NBA1), interval from weaning to first service after first litter (WTS1), number of live-born piglets in the second litter (NBA2), and interval from weaning to first service after the second litter (WTS2). Females generating the data were Norwegian Landrace born in nucleus herds between 1990 and 2000, and the number of records ranged from 13,792 to 56,932. Genetic correlations were estimated among the main production traits in the breeding goal: adjusted age at 100 kg live weight (A100), percentage of lean meat content (LMC), individual feed consumption from 25 to 100 kg (FC), and bacon side quality (BSQ). Average adjusted backfat thickness (BF) was included as a production trait. The A100 and BF traits were recorded on gilts on-farm with 190,454 records, whereas LMC, BSQ, and FC were recorded on-station with the number of records ranging from 12,487 to 12,992. Analyses were carried out with a multivariate animal model using average information restricted maximum likelihood procedures by first running each reproduction trait with A100 and BF, followed by each reproduction trait with LMC, BSQ, and FC. Average heritabilities for reproduction traits were as follows: AFS (0.38), NBA1 (0.11), WTS1 (0.06), NBA2 (0.12), and WTS2 (0.03); and for production traits: A100 (0.30), BF (0.44), FC (0.22), LMC (0.58), and BSQ (0.23). The highest genetic correlation was estimated between A100 and AFS (r(g)= 0.68), also resulting in a positive genetic correlation between FC and AFS. Growth (A100) was negatively (i.e., unfavorably) genetically correlated to NBA1 and NBA2 (r(g) = 0.60 and rg = 0.42 respectively), and so the genetic correlation to FC also became unfavorable (r(g)= 0.23 and r(g) = 0.20). Single-trait selection for enhanced LMC would also affect NBA1 and NBA2 unfavorably (r(g)= -0.12 and r(g)= -0.24). Correlations between BF at 100 kg live weight and reproduction traits were close to zero; however, a low genetic correlation between BF and WTS1 was obtained (r(g)= -0.12), indicating that selection toward reduced BF at 100 kg live weight may have an unfavorable impact on WTS1.

Animals↗

PubMed1984

Estimates of heritabilities and of genetic and phenotypic correlations among growth and reproductive traits in yearling Angus bulls.

Data from Nichols Farm, Anita , Iowa, collected from 1975 through 1980, were used. Angus Herd Improvement Records with birth, weaning and yearling weights were obtained for 717 bulls by 80 sires. Also available, from Hawkeye Breeders Service, Des Moines , Iowa, were measures of sperm concentration and motility, percentage live sperm, number of sperm/ml, semen score and quality and scrotal circumference on the bulls as yearlings . Heritabilities and genetic and phenotypic correlations were estimated for the above traits from variance and covariance components calculated by restricted maximum likelihood. Estimates of heritability for birth, weaning and yearling weight were .70, .46 and .49, respectively. Heritability estimates for the semen traits were low (0 to .24); the estimate for scrotal circumference was .36. In general, genetic and phenotypic correlations among semen traits were high and favorable, with absolute values ranging between .49 and 1.11. Genetic correlations between semen traits and scrotal circumference were low; corresponding phenotypic correlations were moderate. Semen traits were lowly correlated phenotypically with growth traits (-.08 to .08) and genetic correlation estimates were variable. Estimates of phenotypic and genetic correlations suggested that yearling scrotal circumference was more closely related to yearling weight than to either birth or weaning weight. Estimates of phenotypic and genetic correlations between scrotal circumference and yearling weight were .26 and .68, respectively.

Animals↗

PubMed1984

Genetic correlations of pig performance and sow productivity traits.

Records for a total of 732 daughter-dam pairs were analyzed to estimate the genetic correlations of pig performance traits with sow productivity traits, with implications to the development of specialized sire and dam lines for use in crossing. Major pig performance traits analyzed included average daily gain from 56 d of age to a final weight of 90.7 kg (ADG), average backfat thickness at 90.7 kg (BF) and a performance index (PI) consisting of ADG and BF. Major sow productivity traits included number of pigs born alive in a litter (NA), litter size (N21) and litter weight (W21) at 21 d of age and two sow productivity indexes, one with NA, N21 and W21 (SPI-3) and one with NA and W21 (SPI-2). All records were expressed as deviations from breed-line-year-season means of this population. Genetic correlations were computed from daughter-dam covariances. The mean genetic correlation of PI with SPI consisted of two correlations, that of daughters' PI with dams' SPI and that of dams' PI with daughters' SPI. The mean genetic correlation of PI with SPI-3 and SPI-2 was .07 +/- .12, suggesting that concurrent improvement in both PI and SPI would not be restricted by selection within a single composite line. The genetic correlation of daughters' PI with dams' SPI (-.18 +/- .13) was appraised as more critical than the reciprocal correlation of dams' PI with daughters' SPI (+.28 +/- .13). This appraisal is based on the fact that only one generation separates a daughter's PI from her dam's SPI, as compared with two generations in the reciprocal covariance. However, the -.18 correlation was not significantly different from zero, indicating that formation of specialized sire and dam lines for use in crossing would be only marginally more effective at best for improving the overall efficiency in pork production than use of a single composite line, aside from the heterosis effects from crossing the lines. Indexes were proposed for combining PI and SPI for use either in specialized sire and dam lines or in a single composite line.

Animals↗

PubMed1986

Heritability and repeatability of Hereford show-ring placing and associated correlations with individual performance measurements and expected progeny differences.

Data associated with 1,531 Herefords shown at the National Western Stock Show at Denver from 1978 to 1984 were used to estimate heritability and repeatability of show-ring placing (SRP) and genetic, environmental and phenotypic correlations. The correlations were those between: SRP and individual measurements (IM) taken at the time of show and available to the judges, SRP and parents' SRP and IM, male SRP and their individual expected progeny difference values (EPD) and SRP and sire EPD. The IM were height, weight, backfat, weight per day of age and scrotal circumference. The estimation procedures were symmetric differences squared, analysis of variance and parent-offspring regression and correlation. Three similar estimates of SRP heritability averaged .39. Three similar estimates of SRP repeatability averaged .33 and suggested little effective selection for SRP based on first record and low permanent environmental variance. The phenotypic correlations indicated an individual's height (.63) had the most influence on its SRP followed by weight (.43). Genetic and environmental correlations between height and SRP averaged (three estimates) .78 and .37, respectively. Dam SRP, height and backfat had higher correlations with offspring SRP than those of the sire. Male SRP was moderately correlated with EPD values for weaning (.25) and yearling (.38) height and weaning (.33) and yearling (.32) weight. The correlations between SRP and sire EPD values were: .27 (birth weight), .16 (weaning weight), .33 (weaning height), .10 (yearling weight), .23 (yearling height) and .07 (maternal breeding value). The results did not support SRP as a criterion for improving growth performance traits.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1998

Glycerol-induced acute renal failure attenuates subsequent HgCl2-associated nephrotoxicity: correlation of renal function and morphology.

Glycerol induced acute renal failure (ARF) is known to attenuate subsequent mercuric chloride nephrotoxicity. This protection was evaluated in rats. Glycerol induced varying degrees of renal insufficiency. After 14 days, when serum creatinine (SCr) creatinine clearance (CCr) and fractional excretion of sodium (FENa) had returned to baseline, injection of mercuric chloride caused significantly milder renal insufficiency in recovered rats than in controls (SCr 356 +/- 46 vs. 475 +/- 19 mumol/L; CCr 0.12 +/- 0.02 vs. 0.02 +/- 0.02 mL/min, p < .05; and mortality 0 vs. 45%, respectively, p < .01). A striking finding was that the degree of renal insufficiency induced by mercuric chloride correlated inversely with the degree of renal insufficiency previously induced by glycerol (r = -0.496, p < .05 for SCr and CCr), but there was no correlation with other measures of previous renal function such as urine volume, sodium excretion, or FENa. Glycerol induced ARF also attenuated the renal toxicity of mercuric chloride injected 4 days after glycerol, before full recovery of renal function. The decrements in renal function after the two insults were also inversely related (r = -0.76, p < .01). A third renal insult with a second mercuric chloride injection after three weeks was still attenuated. However, after the third insult, there was no longer an inverse or any statistical relationship with previous measurements of renal function. Histopathology revealed a good correlation between peak Scr after glycerol, and percentage of tubules undergoing re-generation 14 days later (r = 0.97, p < .01). There was an inverse correlation between Scr after mercuric chloride (administered 14 days after glycerol) and percentage of tubular regeneration seen two days later (r = -0.79, p < .05). The correlations of SCr and CCr with regeneration was greater than the correlations with tubular necrosis, suggesting that the regenerative process is involved in the protection from repeated renal insults. In conclusion, glycerol-induced ARF attenuates subsequent mercuric chloride renal insult. The attenuation correlates directly with the initial glycerol-induced damage, so that the more severe the initial renal insufficiency, the milder the renal insufficiency following subsequent mercuric chloride. This protection can be seen as early as 4 days and also 14 days after previous renal insult. The degree of renal tubular regeneration correlates well with the protection seen, and probably plays a role in acquired renal resistance to repeated insults.

Acute Kidney Injury↗

PubMed2001

Heritabilities and correlations among body condition scores, production traits, and reproductive performance.

The objectives of this study were to estimate the heritability of body condition scores (BCS) from producer and consultant-recorded data and to describe the genetic and phenotypic relationships among BCS, production traits, and reproductive performance. Body condition scores were available at calving, postpartum, first service, pregnancy check, before dry off, and at dry off from the Dairy Records Management Systems in Raleigh, NC, through the PCDART program. Heritabilities, genetic correlations, and phenotypic correlations were estimated assuming an animal model using average information REML. Herd-year-season effects and age at calving were included in all models. Prior calving interval was included in models for second and third lactations. Analyses that included reproductive traits were conducted with and without mature equivalent milk as a covariable. Heritability estimates for BCS ranged from 0.09 at dry-off to 0.15 at postpartum in first lactation. Heritability estimates ranged from 0.07 before dry-off to 0.20 at pregnancy check in second lactation and from 0.08 before dry-off to 0.19 at first service in third lactation. Genetic correlations between adjacent BCS within first lactation were greater than 0.96 with the exception of calving and postpartum (0.74). In second lactation, adjacent genetic correlations were 1.0 with the exception of calving and postpartum (0.84). Genetic correlations across lactations were greater than 0.77. Phenotypic correlations between scoring periods were highest for adjacent scoring periods and when BCS was lowest. Phenotypic correlations were lower than genetic correlations, i.e., less than 0.70. Higher BCS during the lactation were negatively related to production, both genetically and phenotypically, but the relationship was moderate. Higher BCS were favorably related genetically to reproductive performance during the lactation.

Animals↗

PubMed2003

Heritabilities and correlations among body condition score, dairy form and selected linear type traits.

The objectives of this study were to estimate the heritability of body condition score (BCS) with data that could be used to generate genetic evaluations for BCS in the US, and to estimate the relationship among BCS, dairy form and selected type traits. Body condition score and linear type trait records were obtained from Holstein Association USA Inc. Because BCS was a new trait for classifiers, scoring distribution and accuracy was not normal. Records from 11 of 29 classifiers were eliminated to generate a data set that should represent BCS data recorded in the future. Edited data included 128,478 records for analysis of first lactation cows and 207,149 records for analysis of all cows. Heritabilities and correlations were estimated with ASREML using sire models. Models included age at calving nested within lactation, 5th order polynomials of DIM, fixed herd-classification visit effects and random sire and error. Genetic correlation estimates were generated between first lactation data that had records from 11 classifiers removed and data with no classifiers removed. Genetic correlation estimates were 0.995 and above between data with and without classifiers removed for scoring distributions, but heritability estimates were higher with the classifiers edited from the data. Heritability estimates for type traits and final score were similar to previously reported estimates. The heritability estimate for BCS was 0.19 for first lactation cows and 0.22 for all cows. The genetic correlation estimate for first lactation cows between BCS and dairy form was -0.73, whereas the genetic correlation estimate between BCS and strength was 0.72. Genetic correlation estimates were nearly identical when cows from all lactations were included in the analyses. Body condition score had a genetic correlation with final score closer to zero (0.08) than correlations of final score with dairy form, stature or strength.

Animals↗

PubMed2005

Impact of estimated genetic correlations on international evaluations to predict milk traits.

The Interbull procedure for combining dairy bull evaluations uses estimated genetic correlations between countries. It is important to know whether the resulting difficulties from differences in ranking in each country are justified by improved accuracy relative to a system assuming unity correlations. Data submitted for the May 2001 yield and somatic cell score (SCS) Interbull evaluations were processed once with the usual estimated genetic correlations (E01) and again assuming these correlations to be essentially unity (0.995; U01). The 2 sets of resulting evaluations were compared with August 2004 national evaluations (N04) for bulls not having local evaluations used in the 2001 evaluations. Thus, the examination was of Interbull evaluations from foreign data in predicting national evaluations. Countries in the study for yield were Australia, Canada, France, Germany, Great Britain, Ireland, Italy, The Netherlands, New Zealand, and the United States. Countries included for SCS were Canada, France, Germany, Great Britain, The Netherlands, and the United States. For most countries' evaluations, standard deviations of differences between E01 or U01 and N04 were smaller for E01 by about 5 to 7% and correlations between E01 and N04 were higher by 0.01 or the same as for U01 and N04. Although use of estimated correlations tended to improve prediction, the advantage was small. A previous study had concluded no difference in accuracy for yield but did not include Australia and New Zealand, countries with the lowest correlations with other countries. Excluding bulls from those countries produced results for the other 8 countries more like the previous study, but still favoring E01 slightly. Those 2 countries were not in the SCS data. Estimated genetic correlations improved the prediction of future national evaluations slightly in most countries but more substantially for the evaluations and bulls of Australia and New Zealand.

Animals↗

PubMed1991

Correlations among linear type traits and somatic cell counts.

Genetic and phenotypic correlations between linear type traits and SCC were estimated from lactation average SCC from Pennsylvania DHIA and Holstein linear type evaluations from Sire Power, Inc. and Holstein Association using REML. Correlations were estimated between linear type traits and SCC measured in first lactation and between linear type traits measured in first lactation and SCC measured in second or third lactation. Data sets ranged in size from 4294 daughters of 216 sires to 58,235 daughters of 301 sires. Phenotypic and genetic correlations between the linear traits that reflect body and locomotive characteristics and SCC were generally small and unimportant. Phenotypic correlations between udder traits and SCC were variable, but cows with higher udder depth scores (higher udders) had lower SCC. Genetic correlations between udder traits and SCC were also variable. Genetic correlations between SCC and udder depth, SCC and fore udder attachment, and SCC and teat placement were negative (favorable). Genetic correlations between teat length and SCC tended to be positive. Genetic correlations were largest in magnitude between udder depth and SCC and ranged from -.21 to -.64 (weighted mean = -.35). Selection for higher udders and closer teat placement will likely improve resistance to mastitis in dairy cattle.

Animals↗

PubMed1998

[A canonical correlation analysis on the traffic conditions and the road injury in China in 1996].

In order to expound the impact of traffic condition to road injury, the relations of road injury with motorization, road situation e and highway capacity were studied, using Canonical Correlation analysis method. Results showed that the Canonical Correlation Coefficient A(0.9486) was representing the direct correlation of the motorization with the injury and death rates, referring the higher the motorization, the greater the death and injury rates. The Canonical Correlation Coefficient B(0.9220) indicated the direct correlation between the highway capacity and the frequency of road injury, as well as the larger the highway capacity, the more frequency of road injury occurrance. The Canonical Correlation Coefficient C(0.6446) revealed the relations between levels of road situation and the accident rates per 10,000 vehicles. Results showed that the higher the quality of roadway, the lower was the accident rate. In view of this, traffic condition was closely related to road injury. Thus, the frequency of accident, death rate and injury rate could be reduced through improving the road quality and traffic conditions. Relations between two sets of random variables, the ties of the canonical variables and the original variables could all be well analysed with Canonical Correlation analysis. Canonical Correlation is useful to analyse two sets of random variables in epidemiological studies since it provides a great amount of information to be applied and operated widely and easily.

Accidents, Traffic↗

PubMed1999

Slow EEG-power spectra correlate with haemodynamic changes during laryngoscopy and intubation following induction with fentanyl or sufentanil.

We studied nociception-associated arousal following laryngoscopy and intubation in patients scheduled for elective open heart surgery, using EEG power spectra and hemodynamics. Either fentanyl (7 micrograms/kg; n = 30) or sufentanil (1 microgram/kg; n = 30) were given in a randomized fashion to induce anesthesia in heavily premedicated patients, followed by pancuronium bromide (100 micrograms/kg). EEG-power spectra (delta, theta, alpha, beta) as well as mean arterial blood pressure (MAP) and heart rate (HF) were measured at the following end-points: before the induction of anesthesia (control), 1 and 10 minutes after laryngoscopy and intubation (L & I). Linear regression analysis was computed to determine which of the EEG power spectra was most sensitive to detect insufficient blockade of nociceptive-related arousal when correlated with haemodynamics. In the fentanyl group the change in HF closely correlated with the decrease of power in the slow delta- and theta-domain (r2 = 0.98 and r2 = 0.89 respectively) of the EEG. The change in MAP also closely correlated with a decrease in the slow delta- and theta-domain (r2 = 0.97 and r2 = 0.99 respectively). There was little correlation in regard to spectral edge frequency (SEF) and HF and MAP changes (r2 = 0.36 and r2 = 0.12 respectively). In the sufentanil group the change in HF correlated closely with an increase of power in the fast alpha and a decrease in the slow theta-domain (r2 = 0.91 and r2 = 0.98 respectively) of the EEG. The changes in MAP closely correlated with an increase in the fast alpha-band a decrease in the slow theta-domain (r2 = 0.98 and r2 = 0.73 respectively). Also there was little correlation of SEF with HF and MAP changes (r2 = 0.09 and r2 = 0.02 respectively). Among the EEG-spectra, reduction of power in the slow delta- and theta-bands are the most sensitive parameters to determine insufficient antinociception of opioids commonly used for the induction in cardiac anesthesia. Increase of power in the alpha-band seems to be closely correlated with cortical reactivation and reduction of hypnosis, while a reduction of power especially in the deltabut more so in the theta-band of the EEG reflects nociception related arousal.

Alpha Rhythm↗

PubMedDate not supplied

Clinical and neurophysiological correlations of spasticity.

The aim of this investigation was to explore the correlations between some neurophysiological methods and spasticity. An examination of 120 patients with spastic hemiparesis was performed. The muscle tone, force and tendon reflexes were assessed using well-known five-point scales. The F wave, T, H and flexor reflex parameters and the Hvibrated/Hmaximal ratio were obtained. Our results revealed moderate correlations (0.3 < r < 0.5) between the amplitudes of F wave, T and H reflexes and muscle tone. The correlations between the amplitude ratios (Fmaximal/M, Fmean/M, T/M, H/M) and muscle tone were poor, as were the correlations between H reflex thresholds and muscle tone. Moderate correlations existed between Hvibration/Hmaximal ratio and muscle tone. Only the second flexor reflex response showed moderate correlations with muscle tone. In conclusion correlations between the neurophysiological methods employed and muscle tone are moderate. Evaluation of all the F wave, T, H reflex and flexor reflex parameters is not necessary, as only some of these parameters show good correlations with spasticity.

Aged↗

PubMed2001

Correlated firing in macaque visual area MT: time scales and relationship to behavior.

We studied the simultaneous activity of pairs of neurons recorded with a single electrode in visual cortical area MT while monkeys performed a direction discrimination task. Previously, we reported the strength of interneuronal correlation of spike count on the time scale of the behavioral epoch (2 sec) and noted its potential impact on signal pooling (Zohary et al., 1994). We have now examined correlation at longer and shorter time scales and found that pair-wise cross-correlation was predominantly short term (10-100 msec). Narrow, central peaks in the spike train cross-correlograms were largely responsible for correlated spike counts on the time scale of the behavioral epoch. Longer-term (many seconds to minutes) changes in the responsiveness of single neurons were observed in auto-correlations; however, these slow changes in time were on average uncorrelated between neurons. Knowledge of the limited time scale of correlation allowed the derivation of a more efficient metric for spike count correlation based on spike timing information, and it also revealed a potential relative advantage of larger neuronal pools for shorter integration times. Finally, correlation did not depend on the presence of the visual stimulus or the behavioral choice of the animal. It varied little with stimulus condition but was stronger between neurons with similar direction tuning curves. Taken together, our results strengthen the view that common input, common stimulus selectivity, and common noise are tightly linked in functioning cortical circuits.

Action Potentials↗