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Biomedical subjects

G A Peterson

Publications and source records attributed to G A Peterson.

At least 19 recordsLinked to original sources
PubMed2005

Precision measurement of the weak mixing angle in Møller scattering.

We report on a precision measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: A(PV) = [-131 +/- 14(stat) +/- 10(syst)] x 10(-9), leading to the determination of the weak mixing angle sin2(thetaW(eff) = 0.2397 +/- 0.0010(stat) +/- 0.0008(syst), evaluated at Q2 = 0.026 GeV2. Combining this result with the measurements of sin2(thetaW(eff) at the Z0 pole, the running of the weak mixing angle is observed with over 6sigma significance. The measurement sets constraints on new physics effects at the TeV scale.

Journal Article↗
PubMed2004

Observation of parity nonconservation in møller scattering.

We report a measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: A(PV)=[-175+/-30(stat)+/-20(syst)] x 10(-9). This first direct observation of parity nonconservation in Møller scattering leads to a measurement of the electron's weak charge at low energy Q(e)(W)=-0.053+/-0.011. This is consistent with the standard model expectation at the current level of precision: sin((2)theta(W)(M(Z))((-)MS)=0.2293+/-0.0024(stat)+/-0.0016(syst)+/-0.0006(theory).

Journal Article↗
PubMed2001

Measurement of the elastic magnetic form factor of (3)He at high momentum transfer.

New electron scattering measurements have been made that extend data on the (3)He elastic magnetic form factor up to Q(2) = 42.6 fm(-2). These new data test theoretical conjectures regarding non-nucleonic effects in the three-body system. The very small cross sections, as low as 10(-40) cm(2)/sr, required the use of a high-pressure cryogenic gas target and a detector system with excellent background rejection capability. No existing theoretical calculation satisfactorily accounts for all the available data.

Journal Article↗
PubMed1997

Diversity in case management modalities: the Summit model.

Though ubiquitous in community mental health agencies, case management suffers from a lack of consensus regarding its definition, essential components, and appropriate application. Meaningful comparisons of various case management models await such a consensus. Global assessments of case management must be replaced by empirical studies of specific interventions with respect to the needs of specific populations. The authors describe a highly differentiated and prescriptive system of case management involving the application of more than one model of service delivery. Such a diversified and targeted system offers an opportunity to study the technology of case management in a more meaningful manner.

Adolescent↗
PubMed1996

The effectiveness of outpatient civil commitment.

The effects of outpatient civil commitment on community tenure and functioning were studied in a group of 20 patients with a history of recurrent hospitalizations, noncompliance with outpatient treatment, and good response to treatment. During the first 12 months of outpatient commitment, patients experienced significant reductions in visits to the psychiatric emergency service, hospital admissions, and lengths of stay compared with the 12 months before commitment. They significantly increased the number of appointments kept with their psychiatrist. It appears that when used judiciously, outpatient civil commitment is a helpful tool in maintaining hospital recidivists in the community.

Adult↗
PubMed1996

Documenting informed consent for treatment with neuroleptics: an alternative to the consent form.

Clinicians can comply with Ohio state regulations for documenting patients' informed consent for treatment with neuroleptic medication by checking a box in the medical record stating that a periodic discussion of informed consent has occurred and writing a note about the discussion in the narrative record. The authors discuss clinicians' experience with this alternative to the conventional consent form in a large community support agency. Although the approach has been largely successful, implementation has been hindered by some clinicians' incomplete understanding of the informed consent process. Continued training is needed to bring the ideal of informed consent into clinical practice.

Antipsychotic Agents↗
PubMed1991

Adjustment of pig or litter weights to a 21-day basis in Duroc, Landrace, and crossbred swine.

A total of 457 Duroc, 137 Landrace, 131 Duroc x Landrace, and 110 three-and four-breed crossbred pigs were used to estimate multiplicative adjustment factors. Sixty-one Duroc, 24 Landrace, 18 Duroc x Landrace, and 16 three- and four-breed crossbred litters were weighed every 3 or 4 d from 13 to 30 d of age. Prediction equations for estimating pig weights from birth to 30 d and from 13 to 30 d of age are presented. Multiplicative adjustment factors for adjusting pig or litter weights to a 21-d basis for pigs or litters that are weighed between 13 and 30 d of age for different breeds and crossbred combinations are listed. Breed, litters within breed, and pigs within litter x breed effects adjusted for age at weighing were different (P less than .01). Quadratic regression coefficients of weight on age of pig from 13 to 30 d of age did not differ (P greater than .10) from zero for Landrace and three- and four-breed crossbred pigs but were significant for Duroc and Duroc x Landrace pigs.

Animals↗
PubMed1991

Traits affecting postweaning weight gain and feed intake of primiparous sows.

Seventy-six primiparous Duroc and Landrace sows from two genetic lines with or without selection for improved sow productivity were used to identify sow traits that affect postweaning gain (positive or negative) and feed intake. Sows lost weight (P less than .01) and consumed less feed (P less than .01) during wk 1 postweaning (37 d) compared with wk 2, 3, and 4. Sows gained more weight during wk 2 and 3 (P less than .01) than during wk 4. Weekly feed consumption was similar during wk 2 and 4 and highest during wk 3 (P less than .05). Sow weight gain postweaning was predicted by sow weaning weight (P less than .01) and adjusted 21-d litter weight (P less than .05) during wk 1, wk 1 to 2, and wk 1 to 4 feeding periods. Feed consumption was best predicted by adjusted litter weaning weight (P less than .01), sow weaning weight (P less than .01), average backfat at farrowing (P less than .01), average backfat change (P less than .05), and adjusted 21-d litter weight (P less than .05). Feed intake was positively correlated (P less than .01; r = .77) and sow weight at breeding, farrowing, and weaning was negatively correlated (P less than .05; r = -.23, -.21, and -.26, respectively) with sow weight gain. Average backfat at weaning was negatively correlated (P less than .05) with gain and feed intake during each period. Adjusted 21-d litter weight and adjusted litter weaning weight were positively correlated with postweaning feed intake (P less than .05; r = .22 and .23, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1990

Lactational variation and relationship to postnatal growth of insulin-like growth factor-I in mammary secretions from genetically diverse sows.

Mammary secretions obtained from four groups of sows at parturition and on days 7, 14 and 21 of lactation were defatted and assayed for total protein and insulin-like growth factor-I (IGF-I). Sows (n = 57) represented two breeds (Landrace and Duroc) and two genetic lines (selected for differences in sow productivity index, SPI) within each breed. Colostrum of Duroc sows was 4-6 fold and 30-60 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk from these sows. In contrast, the colostrum of Landrace sows was 2-3 fold and 30-50 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk. The IGF-I content in milk from Duroc sows did not differ among days 7, 14 and 21 of lactation, whereas the IGF-I content of day 7 milk from Landrace sows exceeded those for the corresponding 14 day and 21 day secretion (P less than .05). IGF-I concentration in days 14 and 21 milk was higher in Duroc (P less than .001 respectively) than Landrace sows. No significant differences in total protein or IGF-I content of mammary secretions were observed between the selected and control lines within each breed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Different rates of improvement of different symptoms in combined pharmacological and behavioral treatment of agoraphobia.

This study was designed to see whether the high vs low serum level of imipramine influenced the outcome of in vivo exposure therapy on patients with agoraphobia. Thirty-six subjects completed the Hopkins Symptom Checklist-90 one week before treatment and weekly throughout treatment. Both groups demonstrated equal improvement. It was noted that the rate of improvement differed for different symptom subscales: (1) Hostility, Paranoia and Psychotic symptom ratings improved over the first three weeks of treatment, (2) Interpersonal Sensitivity, Anxiety and Depression ratings improved throughout the first seven weeks of treatment and (3) Phobic Anxiety, Somatization and Obsessive Compulsure symptom ratings continued to improve throughout the entire 12 week course of treatment. Responsive vs nonresponsive subjects could be significantly differentiated after one week of treatment on the basis of their responses to the Psychoticism subscale.

Adolescent↗
PubMed1988

Drug-induced relaxation of supercoiled plasmid DNA in Bacillus subtilis and induction of the SOS response.

Whereas treatment with many different drugs led to induction of the SOS response in Bacillus subtilis, only inhibitors of DNA gyrase subunit B and, unexpectedly, polyether antibiotics (membrane ionophores) led to relaxation of supercoiled plasmid DNA. However, treatment with DNA gyrase subunit B inhibitors but not with polyethers led to SOS induction. Thus, the presence of underwound supercoiled DNA was not sufficient to induce the SOS response. Possible mechanisms by which polyethers induce relaxation of supercoiled DNA in vivo are discussed.

Bacillus subtilis↗
PubMed1987

Synchronization of estrus in beef cows and heifers with fenprostalene, cloprostenol sodium, and prostaglandin F2 alpha.

The effects of fenprostalene, cloprostenol sodium and prostaglandin F2 alpha (PGF2alpha) on estrus, conception rate, pregnancy rate, and the interval from Day 1 of the breeding season to calving were studied on 135 purebred Angus cows and heifers. The cows and heifers were randomly allotted within age to the three estrus synchronization treatments and a control group. The calving percentages (for cows and heifers combined) that resulted from artificial insemination (AI) were 32.3, 31.4, 43.6, and 51.1% for the control, fenprostalene, cloprostenol sodium, and PGF2alpha groups, respectively. The calving percentage during the AI period by ages of dam at breeding were 54.2% for yearling heifers, 30.5% for two-year-olds, 47.6% for three-year-olds, and 26.1% for four-year-old or older cows. The percentage of cows and heifers detected in estrus and the percentage that conceived after the first injection for control, fenprostalene, cloprostenol sodium, and PGF2alpha groups were 51.6 and 22.3%, 59.3 and 32.1%, 76.8 and 44.1%, and 66.6 and 50.2%, respectively. The intervals from Day 1 of the breeding season to calving and from Day 1 of the calving season within each treatment to the birth of each calf were control, 285.9 and 23.8 d; fenprostalene, 283.6 and 13.4 d; cloprostenol sodium, 285.5 and 6.5 d; and PGF2alpha, 284.0 and 11.1 d.

Journal Article↗
PubMed1985

The dexamethasone suppression test in agoraphobia.

Patients diagnosed as having agoraphobia with panic attacks by DSM-III criteria were evaluated with the dexamethasone suppression test (DST). Depressive symptoms were assessed using the Beck Depression Inventory, the Depression Scale of the Minnesota Multiphasic Personality Inventory, and the Hamilton Rating Scale for Depression. Of 97 patients tested, 12.4% had a positive DST. These findings are consistent with earlier reports that found an incidence of abnormal DSTs between 11% and 15% in agoraphobic patients. Abnormal DSTs did not correlate with levels of depression on any of the depression measures.

Adult↗
PubMed1985

The stimulation of bioluminescence in Photobacterium leiognathi as a potential prescreen for antitumor agents.

The stimulation of bioluminescence in Photobacterium leiognathi has previously been described as a test for genotoxic compounds. An adaptation of this procedure has been developed which uses a dim variant of P. leiognathi and permits the prescreening of microbial fermentation broths for potential antitumor agents. Bioluminescence in this organism was stimulated by compounds which bind to DNA or affect DNA synthesis. Antibiotics with target sites such as protein, cell wall or RNA synthesis, did not alter bioluminescence. Fermentation broths from over 5,000 soil isolates were prescreened in this assay and 95 (1.6%) were defined as active. Further analysis of selected cultures suggested that about half produced compound(s) with DNA-binding activity. These results suggest that the photobacterium induction assay (PIA) may be useful as a prescreen for potential antitumor agents. The assay is rapid, simple and requires only microgram quantities of material for testing.

Antibiotics, Antineoplastic↗
PubMed1985

A case of homosexual erotomania.

Erotomania has previously been described exclusively in terms of delusional heterosexual relationships, and almost all of the patients reported to manifest this syndrome are women. We report the case of a schizophrenic man with a chronic, fixed delusion involving a homosexual lover. Theoretical implications regarding the psychodynamics of this syndrome are discussed.

Adult↗