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J R Graham

Publications and source records attributed to J R Graham.

At least 37 records · Page 2Linked to original sources
PubMed1995

The fragment R collision: W. M. Keck telescope observations of SL9.

The W. M. Keck telescope was used to observe the impact of comet Shoemaker-Levy 9 (SL9) fragment R at a wavelength of 2.3 micrometers on 21 July 1994. The data showed three outbursts. The first flash lasted about 40 seconds and was followed 1 minute after its peak by a second flash that lasted about 3 minutes. A third, longer lasting flare began 6 minutes after the first flash and lasted for 10 minutes. At its maximum brightness, the flare outshone Jupiter. The two short flashes are probably associated with the initial meteor trail and the subsequent fireball, respectively. The bright flare occurred when the impact site rotated into view. These data show that the explosion ejected material at least 1300 kilometers above the visible cloud tops. The luminosity of the impact site during the long bright flare was probably maintained by the release of gravitational potential energy, as this material fell back onto the lower atmosphere.

Atmosphere↗
PubMed1995

Leber's hereditary optic neuropathy plus dystonia is caused by a mitochondrial DNA point mutation.

A novel point mutation in the ND6 subunit of complex I at position 14,459 of the mitochondrial DNA (MTND6*LDY T14459A) was identified as a candidate mutation for the highly tissue-specific disease. Leber's hereditary optic neuropathy plus dystonia. Since the MTND6*LDYT14459A mutation was identified in a single family, other pedigrees with the mutation are needed to confirm its association with the disease. Clinical, biochemical, and genetic characterization is reported in two additional pedigrees. Leber's hereditary optic neuropathy developed in two family members in one pedigree. The daughter had clinically silent basal ganglia lesions. In a second pedigree, a single individual presented with childhood-onset generalized dystonia and bilateral basal ganglia lesions. Patient groups that included individuals with Leigh's disease, dystonia plus complex neurodegeneration, and Leber's hereditary optic neuropathy did not harbor the MTND6*LDYT14459A mutation, suggesting that this mutation displays a high degree of tissue specificity, thus producing a narrow phenotypic range. These results confirm the association of the MTND6*LDYT14459A mutation with Leber's hereditary optic neuropathy and/or dystonia. As the first genetic abnormality that has been identified to cause generalized dystonia, this mutation suggests that nuclear DNA or mitochondrial DNA mutations in oxidative phosphorylation genes are important considerations in the pathogenesis of dystonia.

Adolescent↗
PubMed1995

Detecting fake-bad MMPI-A profiles.

This study examined the extent to which the validity scales of the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; Butcher et al., 1992) could identify adolescents who were faking-bad. This study also examined the extent to which the validity scales could differentiate between nonclinical adolescents instructed to fake-bad and both clinical and nonclinical adolescents who received standard instructions. Participants were 58 male and 80 female high school students and 58 male and 80 female adolescents from clinical settings. Results indicated that the mean profiles resembled those previously reported for adults on the MMPI (Graham, 1987) and MMPI-2 (Graham, Watts, & Timbrook, 1991) and for adolescents on the original MMPI (Archer, Gordon, & Kirchner, 1987). Accurate identification of students who were faking-bad was achieved. It was possible to differentiate between the clinical adolescents and nonclinical adolescents who were faking, and it was possible to differentiate between nonclinical adolescents who were faking and nonclinical adolescents with standard instructions; however, different cutoff scores were needed for these two discriminations. Optimal cutoff scores were presented.

Journal Article↗
PubMed1994

Temporal pattern of rat small intestinal gene expression with refeeding.

Studies were carried out to elucidate the molecular mechanisms underlying small intestinal epithelial growth. Adult rats were fasted for 4 days and then refed a chow diet for up to 48 h. Histological examination confirmed the sequential occurrence of mucosal atrophy and hyperplasia. Northern blot analyses of RNA derived from small intestinal mucosal scrapings revealed a striking pattern of alterations in the expression of two different categories of genes. There were very early increases in the expression of c-fos and c-jun, reflecting the mitogenic response to refeeding that occurs within the crypt compartment. Studies using the protein synthesis inhibitor cycloheximide suggest that c-fos and c-jun are part of the "immediate-early" response of the small intestine. At later time points after the refeeding stimulus, differential changes occurred in the expression of the brush-border enzymes, lactase, and intestinal alkaline phosphatase (IAP). Refeeding caused a decrease in lactase gene expression and an increase in the expression of the 3.0-kb IAP mRNA species, reflecting a return of the villus phenotype to the normal fed state. Thus we have demonstrated a complex and temporally related pattern of gene expression within the small intestinal epithelium upon refeeding. The results provide insight into the relationship between the processes of intestinal growth and differentiation.

Animals↗
PubMed1993

The meaning of low scores on MMPI-2 clinical scales of normal subjects.

Low scores often have been ignored in validity research on the MMPI, yet these statistically significant deviations from the norm may be valuable sources of information and occur frequently enough to merit further investigation. The meaning of low scores on the MMPI-2 was examined for 822 male-female partner pairs in the MMPI-2 restandardization sample. Subjects were divided by MMPI-2 scale scores into high-, medium-, and low-score groups. Analyses of variance were performed with score level as the independent variable and partner ratings as dependent variables. Significant differences were found between the low- and medium-score groups with low scorers rated as better adjusted that medium scorers. More significant differences were found between the high-score and medium-score groups than between the low-score and medium-score groups; this suggested that high scores on MMPI-2 clinical scales are associated with poorer adjustment.

Adolescent↗
PubMed1991

Three methods of developing MMPI taxonomies of sexual offenders.

In a sample of 261 state hospital sexual offenders, Minnesota Multiphasic Personality Inventory (MMPI) profiles did not differ for offenders with adult victims versus offenders with child victims when offender age was controlled. MMPI 2-point analyses for the whole sample revealed five common codes that were independent of victim maturity. The sample was randomly divided in half and subjected to a cluster-analytic procedure which revealed two MMPI clusters. The first cluster was unelevated, with Scale 4 as its high point. The second cluster had multiple elevations, with Scales 8, 4, 2, and 7 as the highest scales. These clusters were replicated in a cluster analysis of the second half of the sample. However, when the sample was recombined, the two clusters were not externally validated basis on demographic and criminological variables. The results suggest that common psychological variables among sexual offenders may have more discriminative value than victim maturity in developing sexual offender taxonomies.

Adult↗
PubMed1991

The Masculinity-Femininity Scale of MMPI-2: is it useful with normal men?

Using ratings provided by significant others, we examined characteristics of 819 normal men whose scores on the Masculinity-Femininity scale (Scale 5) of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) ranged from low to high. Also examined were the possible effects of educational level as a moderator variable. Only one external characteristic was correlated with Scale 5 scores at a level of significance that could not be attributed to chance, and that correlation was negative, whereas previous literature indicated a positive relationship. The findings were essentially the same whether or not the effects of education were controlled. Regardless of Scale 5 scores and the higher the men's educational levels, the more positive were ratings by their partners. In general, the results do not support the usefulness of Scale 5 in describing the personalities and behaviors of normal men.

Adult↗
PubMed1991

Detecting fake-good and fake-bad MMPI-2 profiles.

This study examined the extent to which the validity scales of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) could identify subjects who were faking bad or faking good and differentiate between psychiatric patients and normal subjects who were faking bad. Subjects were 106 undergraduate college students and 50 psychiatric patients. Results indicate that the mean profiles and optimal cutoff scores resembled those previously reported for the original MMPI. Accurate identification of persons who were faking bad or faking good was achieved. It was possible to differentiate between the psychiatric patients and normal persons who were faking bad, but different cutoff scores were needed to differentiate between normals taking the test under standard instructions and those instructed to fake bad. Optimal cutoff scores were suggested.

Adult↗