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E Stephenson

Publications and source records attributed to E Stephenson.

14 recordsLinked to original sources
PubMed2006

Polarized proton collisions at 205 GeV at RHIC.

The Brookhaven Relativistic Heavy Ion Collider (RHIC) has been providing collisions of polarized protons at a beam energy of 100 GeV since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the intrinsic spin resonances beyond 100 GeV are about a factor of 2 stronger than those below 100 GeV making it important to examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were first accelerated to the record energy of 205 GeV in RHIC with a significant polarization measured at top energy in 2005. This Letter presents the results and discusses the sensitivity of the polarization survival to orbit distortions.

Journal Article↗
PubMed1996

Percutaneous feeding tube changes in long-term-care facility patients.

OBJECTIVE: To compare patient outcomes when percutaneous feeding tubes were changed routinely each month or only when necessary (prn). DESIGN: Prospective, randomized, nonblinded crossover study of 6 months of routine monthly changes compared with 6 months of prn changes. SETTING: 416-bed long-term-care facility. PATIENTS: 26 permanent residents with nutrition managed through percutaneous gastrostomy or jejunostomy feeding tubes. The median age was 61.5 years; 8 (31%) also had tracheostomies, and 3 (12%) had indwelling urinary catheters. RESULTS: The frequency of feeding tube changes was 40 per 1,000 patient-days during the 6 months of routine tube changes and 14 per 1,000 when tubes were changed prn (P < .001). There were no differences between the two study periods in frequency of stoma site infections, fever, episodes of emesis, and total antibiotic courses. The median duration in situ of feeding tubes with prn changes was 104 days. For both periods, feeding tubes were significantly more likely to fall out and require replacement with-in 24 hours of previous tube replacement. CONCLUSION: There were no observed differences in clinical outcomes in long-term-care facility patients when feeding tubes were changed only as necessary as compared to routine monthly changes.

Adult↗
PubMed1988

Vegetarian diet and cobalamin deficiency: their association with tuberculosis.

To determine whether the high incidence of tuberculosis among Asiatic Indians in the United Kingdom was due to impaired killing of Mycobacterium tuberculosis by macrophages from patients deficient in cobalamin, a nutritional survey was carried out among 1187 Indians and the incidence of tuberculosis determined from medical records. The question asked was whether tuberculosis was significantly more common among life-long vegetarians compared with omnivores. The incidence of tuberculosis in vegetarians was 133 in 1000 and that in subjects on mixed diets 48 in 1000. These findings lend support to the hypothesis that dietary factors are of major importance in determining the susceptibility of Asiatic Indians to tuberculosis.

Adult↗
PubMed1982

Bile acids. LXVII. The major bile acids of Varanus monitor.

The major bile acids of gall bladder bile of Varanus monitor have been separated by thin-layer chromatography and shown to be derivatives of taurine. After alkaline hydrolysis, the free acids were separated by thin-layer and partition chromatography. Identification or characterization of the free acids was facilitated by gas-liquid chromatography and gas-liquid chromatography-mass spectometry of the methyl esters or methyl ester-trimethylsilyl ethers. About 13% of the total bile acids was represented by the C24 acids cholic, deoxycholic, allocholic, chenodeoxycholic, and 12-oxo-3 alpha-hydroxy-5 beta-cholanic acids, of which cholic acid constituted about 50%. The remainder of the bile acids consisted of eight C27 acids of which varanic acid was the major constituent; an isomer of varanic acid and 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholestanoic acid were also identified. By chromatographic behavior and mass spectral fragmentation, the structures of four C27 acids with unsaturated side chains were elucidated as follows: 3 alpha, 7 alpha-dihydroxy-5 beta-cholest-23-enoic, 3 alpha, 7 alpha-dihydroxy-5 beta-cholest-24-enoic, 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholest-23-enoic, and 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholest-24-enoic acids. Similarly, the structure of the 12-deoxy analog of varanic acid, 3 alpha, 7 alpha, 24 xi-trihydroxy-5 beta-cholestanoic acid, was suggested for the component that constituted 7% of the total.

Animals↗
PubMedDate not supplied

Postoperative pulmonary complications in calves after implantation of an electric total artificial heart.

In long-term studies testing the Penn State Total Artificial Heart involving 30 calves, seven calves died of pulmonary complications within 2 weeks after receiving the implant (Group 1 [G1]) and seven calves survived from 2 weeks to 3 months without infection (Group 2 [G2]). Comparative studies were performed using multiple variables: cardiopulmonary bypass (CPB) time, cardiac index, central venous pressure, leukocyte count, hematocrit, total protein, albumin, serum glutamic oxaloacetic transaminase (GOT), creatinine, water balance, and transfused blood volume. In G1, CPB time was longer than in G2 (182 +/- 19 vs 156 +/- 17 minutes, respectively, p = 0.018). Postoperative minimum total protein and albumin in G1 were lower than those in G2 (56.5% +/- 6.0% and 59.0% +/- 5.5% of preoperative values vs 68.4% +/- 8.5% and 67.8% +/- 6.1%, respectively, p = 0.011 and 0.015). Water balance in G2 was more positive than in G1 (11.7 +/- 6.8 vs 1.4 +/- 8.3 L, respectively, p = 0.020). Other variables showed no significant differences. Microscopic findings of the lung in G1 were congestion, hemorrhage, aggregation of neutrophils, and proteinaceous material within the interstitial tissues and alveoli.

Animals↗
PubMedDate not supplied

Cost-effective use of helicopters for the transportation of patients with burn injuries.

We performed a retrospective review to analyze the use of helicopters for the transportation of patients with burn injuries to determine whether a more cost-effective approach could be developed without impairing the quality or delivery of health care. Charts were reviewed for all patients with burn injuries who were transported by helicopter to our hospitals during a 2-year period. Patients with inhalation injuries, with burn injuries received more than 24 hours before admission or more than 200 miles from our burn center, with more than 30% total body surface area (TBSA) burned, or with associated trauma injuries were excluded. Control patients with burn injuries who were transported by ambulance were identified and matched to the patients with burn injuries transported by helicopter for the percentage of TBSA burned, the percentage of third-degree burns, transport mileage, and age. The outcome was evaluated by comparison of length of stay, days on ventilator, and mortality rate. Comparisons were performed with Student t test. The transportation charge was determined for the patients transported by helicopter who we believed were eligible for transport by ambulance. Forty-seven of 85 patients transported by helicopter matched the inclusion criteria and had survived. There was no statistically significant difference between the percentage of TBSA burned, the percentage of third-degree burns, length of stay, days on ventilator, age, or transport mileage. There was, however, a significant difference in the time from the injury to admission to the hospital, as well as in the charge for transportation. Patients who had less than 30% TBSA thermal cutaneous injuries without evidence of inhalation injury, and who are less than 200 miles from a burn center may be safely transported by ambulance. Ambulance transportation may take additional time; however, stricter protocols for helicopter transportation of patients with burn injuries will result in potentially substantial savings without affecting outcomes for patients.

Adolescent↗
PubMedDate not supplied

Motor/learning difficulties and the family.

The work reported here, which has as its central concern family dynamics and relationships, is part of a wider study of 31 children with motor/learning difficulties. All the children were attending an Occupational Therapy Department and had been assessed as having motor/learning difficulties. Descriptions of family background, structure and composition are provided and findings on conjugal, parent/child, sibling and extended family relationships presented. Characteristic patterns of family interaction are identified and factors affecting family cohesion discussed.

Achievement↗
PubMedDate not supplied

The identification and treatment of motor/learning difficulties: parents' perceptions and the role of the therapist.

The diagnostic experience of 31 children, assessed as having motor/learning difficulties, attending an occupational therapy department within a children's hospital, was investigated. The study demonstrates the difficulty of specific identification of perceptuomotor problems. Close examination of the children's individual diagnostic pathways revealed a high number of health-care professional contacts and the fact that frequently there were lengthy gaps between parental (and sometimes professional) suspicions and final confirmation. The children's diagnostic experiences prior to starting treatment were varied and involved, and no one single route was predominant. The rationale for occupational-therapy assessment and treatment of this disorder is described, and parental perceptions of its effect are discussed. The findings suggest that an important part of therapeutic intervention may be increasing children's self-confidence and reducing intra and extra family tensions. Fewer behavioural problems were reported once treatment had commenced. It was concluded that an important part of the therapist's role was to provide information and support for parents and to liaise with school teachers, in addition to treating the children themselves.

Child↗