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S J Shaw

Publications and source records attributed to S J Shaw.

At least 19 recordsLinked to original sources
PubMed2001

Experimental observations of the stress experienced by a solid surface when a laser-created bubble oscillates in its vicinity.

In an attempt to shed more light on the complex process by which cavities interact destructively with rigid boundaries we consider experimentally the interaction of a laser-generated bubble with a nearby solid boundary. To determine the stresses the surface of the boundary experiences, particularly during the final stages of the first collapse phase, we present a series of pressure transducer traces observed when the laser-created cavity is produced close to the solid boundary. Through careful control of experimental parameters we record pressure increases for cavities created between 0.56 and 1.5 times the maximum bubble radius from the solid boundary. Previous studies have shown this to be a complex process which is particularly sensitive to the working parameters of the problem, which is borne out by our observations.

Journal Article↗
PubMed2001

Autoantibodies and human leucocyte antigen class II in first-degree family members of Mexican-American type 1 diabetic patients.

As part of a genetic study of type 1 diabetes in Mexican-Americans, 360 first-degree relatives of 108 type 1 diabetic probands were studied. Islet cell antibody (ICA), insulin autoantibody, glutamic acid decarboxylase (GAD(65)), and protein tyrosine phosphatase autoantibodies were measured and human leucocyte antigen (HLA) class II alleles DRB1 and DQB1 genotyping was performed. ICA was positive in 37% of the probands and 5.8% of the relatives. A subgroup of 26 probands (12 ICA+, 14 ICA-) was tested for GAD(65) and was found positive. 4/14 ICA+ first-degree relatives were GAD(65) positive. Four relatives, positive for two antibodies, subsequently developed type 1 diabetes. Life-Table analysis of first-degree relatives with autoantibodies indicated an 80% disease-free survival at 3.5 yr. HLA-DRB1 was found to be associated with the presence of ICA in both probands and relatives, whereas HLA-DPB1 was associated with autoantibody in relatives of type 1 diabetic probands. These results suggest that autoimmunity occurs in type 1 diabetes families of Mexican descent in similar frequencies to that of non-Hispanic, Caucasian families. The presence of autoantibodies appears to be regulated in part by HLA class II genes, even in the absence of overt diabetes.

Adolescent↗
PubMed1998

Performance of the Dynabeads anti-Salmonella system in the detection of Salmonella species in foods, animal feeds, and environmental samples.

The immunomagnetic separation Dynabeads anti-Salmonella technique was evaluated for the detection of Salmonella species in a variety of foods, feeds, and environmental samples. Salmonella cells in preenrichment broths were captured using the Dynabeads anti-Salmonella system and were then washed and plated on indicator media. A total of 308 naturally contaminated samples were analyzed, including 46 cheese and egg products, 183 animal feeds, and 79 environmental swabs. The results of the Dynabeads method gave 100% correlation with the results of the standard culture technique used for foods and the modified semisolid Rappaport-Vassiliadis method used for feeds and environmental samples.

Animal Feed↗
PubMed1996

Association of HLA-DPB1*0301 with IDDM in Mexican-Americans.

Susceptibility to IDDM has been associated with specific alleles at the HLA class II loci in a variety of human populations. Previous studies among Mexican-Americans, a group ancestrally derived from Native Americans and Hispanic whites, showed that the DR4 haplotypes (DRB1*0405-DQB1*0302 and DRB1*0402-DQB1*0302) and the DR3 haplotype (DRB1*0301-DQB1*0201) were increased among patients and suggested a role for both DR and DQ alleles in susceptibility and resistance. Based on the analysis of 42 Mexican-American IDDM families and ethnically matched control subjects by polymerase chain reaction/sequence-specific oligonucleotide probe typing, we report an association of IDDM with the DPB1 allele, *0301 (relative risk = 6.6; P = 0.0012) in this population. The analysis of linkage disequilibrium patterns in this population indicates that the observed increased frequency in DPB1*0301 among patients cannot be attributed simply to linkage disequilibrium with high-risk DR-DQ haplotypes. These data suggest that in addition to alleles at the DRB1 and DQB1 loci, polymorphism at the DPB1 locus may also influence IDDM risk.

Cell Line, Transformed↗
PubMed1993

Gallbladder dysfunction in diabetes mellitus.

To further elucidate the mechanism of impaired gallbladder emptying in diabetics with and without neuropathy, gallbladder function was assessed by ultrasonography following a medium-chain triglyceride (lipomul, 1.5 mg/kg) infusion into the duodenum and compared to that during intravenous infusion of cholecystokinin in diabetic women. Results were compared with five healthy control women. Mean (+/- SD) maximal percent gallbladder volume in diabetics following lipomul was reduced to 49 +/- 8% and after intravenous cholecystokinin to 47 +/- 9%, which was less than those in controls, 21 +/- 9% and 24 +/- 6%, respectively, but not significantly different. Further analysis of gallbladder emptying to lipomul differentiated two subgroups of diabetics: one subgroup (N = 5) had emptying comparable to controls (responders), while the other (N = 5) had very modest emptying (nonresponders). Two of the patients in the latter group had normal gallbladder emptying during exogenous cholecystokinin and their response would be compatible with visceral neuropathy. Blood levels of cholecystokinin, measured by bioassay, following lipomul and exogenous cholecystokinin were similar in controls and diabetics. Presence of diabetic neuropathy did not correlate with impaired gallbladder emptying. Follow up at 6 and 12 months of the three nonresponder diabetics revealed that no gallstones had developed and that two of them became responders to exogenous cholecystokinin.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Ancestral origin of insulin-dependent diabetes in Mexican-Americans.

To test the hypothesis that insulin-dependent diabetes mellitus in the Mexican-American population is due to Spanish genetic admixture, we obtained ancestral information on 106 Mexican-American families with an insulin-dependent diabetic index case and 80 Mexican-American control families from 1987 to 1991. The Mexican states of origin were available on 395 grandparents of the insulin-dependent diabetic index cases and 291 grandparents of the controls. Analysis of the individual states of origin revealed that there were significantly more Mexican-American grandparents of diabetic index cases from the states of Jalisco and Michoacan when compared to the control families (31% and 16% diabetic versus 22% and 11% controls respectively, P less than 0.01). The states of Zacatecas and Durango had a lower frequency of diabetic grandparents as compared to controls (6% diabetic versus 12% controls, P less than 0.001). Analysis of the origin by Northern and Southern states of México revealed a significant decrease in the number of grandparents of the insulin-dependent diabetic cases from the Northern regions of México, 19.5%, versus 32% in controls, (P less than 0.001). These data indicate that the grandparents of the insulin-dependent diabetic index cases originate from states and regions of México which were those of the early entry of the Europeans. These data thus support the hypothesis that insulin-dependent diabetes mellitus in the Mexican-American population may be due in significant part to an original genetic contribution from the Spanish-European population.

Adolescent↗
PubMed1987

Combined supraduodenal and transduodenal exploration of the common bile duct with sphincterotomy.

From a consecutive series of 2,221 cholecystectomies, 177 patients underwent combined supraduodenal and transduodenal exploration of the common bile duct and 390 were treated by supraduodenal exploration alone. The mortality rate after both exploration procedures was the same (2.8 per cent). However, two patients died of septic complications associated with duodenal fistulas in the combined exploration group. Five patients had retained stones in the common bile duct which subsequently flushed out with a saline solution irrigation administered through the T tube in three patients and the stone passed spontaneously in one patient. Clinically significant and biochemically documented acute pancreatitis occurred in five patients, one of whom died. Four patients had postoperative cholangitis develop which responded to antibiotic therapy. We are not aware of any patient who had common bile duct stones, chronic pancreatitis or ampullary stenosis after the combined procedure at follow-up study of between six months and 13 years.

Aged↗
PubMed1985

Team approach in mental health services: generalists or specialists?

Psychiatrists, psychologists, and social workers were compared on their assessments of pathology, treatment techniques, and theoretical orientation for a typical hospitalized psychiatric patient. The purpose was to determine the relationship between treatment-team members' professional discipline and their clinical approach to a patient. Clinical discipline was significantly related to assessment, treatment, and theory. Psychiatrists favored medication, hospitalization, support, and brief, infrequent structured treatment focused on the present and external factors with an aim of social adaptation. Social workers were similar, but added types of treatment and longer, more frequent treatment. Psychologists were unique with an emphasis on psychoanalytically oriented psychotherapy aimed at personality change.

Adult↗
PubMed1985

Preoperative intraincisional cefamandole reduces wound infection and postoperative inpatient stay in upper abdominal surgery.

The use of preoperative intraincisional (POII) single dose antibiotic prophylaxis has the advantage of providing extremely high concentrations of antibiotic along all layers of the wound, whilst achieving adequate systemic concentrations throughout the operation. In a single blind controlled trial, 250 patients undergoing upper abdominal surgery were randomised to receive POII cefamandole (2g) or to act as control. There was one wound infection in the POII group compared with 18 in the control group (P less than 0.001). Hospital stay was reduced by an average of one day (P less than 0.02) in the antibiotic treated group.

Abdomen↗
PubMedDate not supplied

Dealing with difficult students in the classroom.

Despite the proliferation of literature on dealing with difficult people, little has been written on how to manage problematic students in the classroom. Every teacher encounters difficult students because the classroom is merely a microcosm of the outside world. Nursing educators strive to create an open and caring atmosphere in their classes, but it is still necessary to intervene when students disrupt the class by showing disrespect for others or by getting the discussion off track. The authors describe the most common difficult student roles seen in the classroom and suggest strategies for dealing with them.

Adaptation, Psychological↗