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The elastoplastic properties of a stainless steel with an austenitic matrix and martensitic inclusions induced during cyclic tensile-compressive fatigue loading were studied using neutron diffraction. Specimens of annealed and quenched AISI type 321 steel were subjected to low cycle fatigue ( strain amplitude of 1% at 0.5 Hz). Subsequent in situ loading tests provided the elastoplastic responses of both austenitic and martensitic phases via Rietveld refinement of neutron diffraction spectra. A clear trend of increasing elastic modulus with increasing fatigue level was noted in the austenite matrix. The results of modified refinements accounting for the elastic anisotropy in polycrystalline materials under load are presented. The residual strains in the austenitic matrix and the deviatoric components of both phases' residual microstresses were determined as a function of fatigue cycling. In the Appendix it is demonstrated that the presence of residual stresses can have an effect on the observed elastic moduli in a two phase system, but that for typical magnitudes the effect is negligible.

This paper examines the Scottish fiddling revival in America. Due to its rapid fusion into other fiddling styles, Scottish fiddling did not establish itself as a unique musical genre in the United States. One particular organization, titled “Scottish Fiddling Revival,” or “F.I.R.E.,” is largely responsible for the revival and has established all of the necessary elements within a revival framework to stimulate and maintain this style of fiddling. The organization sponsors official Scottish fiddling competitions, provides teachers to educate and maintain the style, and fosters a community to interact with the revival. This study examines the revival infrastructure and its implications according to an established framework for the continued development of Scottish fiddling in the United States.

The CMS detector at the CERN Large Hadron Collider is being built to study particle physics at the energy frontier. An important detector subsystem of CMS is the hadron calorimeter (HCAL), used for the measurement of particle and jet energies and to identify and measure missing transverse energy in collision events. This paper provides details of the electro-optical interfaces for the barrel and endcap regions of the HCAL called readout boxes (RBX). These system elements are located "on detector" and operate in regions of very high magnetic field, converting scintillation signals for megatile sampling layers to tower geometry for energy measurement.

The CMS Hadron Calorimeter (HCAL) will use optical decoder units (ODU) as a link between scintillating plastic tiles, arranged in megatile layers around the HCAL, and multi-channel hybrid photodiodes. Photons are produced in the scintillating tiles as sub-atomic particles pass through and deposit energy. Y-11 waveshifting fiber and cables of clear optical fiber serve as connecting transmission lines from scintillating tiles to the ODU. The ODU reorganizes light signals from layer geometry to tower geometry for particle energy measurement. The hybrid photodiode (HPD) converts the light signals to electrical signals that are amplified and digitized for the data acquisition system. This paper provides aspects of the production of optical decoder units.

The results of the 1974 A/S/G/E survey of complications relating to colonoscopy and polypectomy are analyzed. Members reported 25,298 diagnostic colonoscopies with a morbidity of 0.32% and a mortality of 0.008%. The most common complication of diagnostic colonoscopy was perforation (55 cases or 0.22%). The only fatalities (2) were associated with perforation. There were 6,214 colonoscopic polypectomies reported with a morbidity of 2.3% and no mortality. The most common complication of polypectomy was hemorrhage (115 cases or 1.9%).

Lower oesophageal sphincter pressure has been studied in pernicious anaemia patients and controls using an infused open-tipped system. Resting sphincter pressure was significantly (p In conclusion, the lower oesophageal sphincter in pernicious anaemia is characterized both by a low resting pressure and a decreased response to endogenous and exogenous stimuli. These results suggest a primary end organ defect and most likely indicate abnormal smooth muscle function in pernicious anaemia. Resting sphincter pressure levels and edrophonium response in age-matched subjects indicate that these changes are not due to aging alone.

Complications associated with esophagogastroduodenoscopy and with esophageal dilation Paul Mandelstam, MD Lexington, Kentucky Choichi Sugawa MD Detroit, Michigan Stephen E. Silvis, MD Minneapolis, Minnesota Otto T. Nebel, MD Solana Beach, California B. H. Gerald Rogers, MD Chicago, Illinois Among 211,410 peroral endoscopic examinations reported in a survey of AISIGIE members, the overall rate of complications was 1.32/1000. The complication rates for esophageal dilation ranged from 4.25 to 18.4/1000, depending on the technique employed. Major complications included perforation, hemorrhage from biopsy, aspiration, myocardial infarction, cardiac arrest and arrhythmia, and respiratory arrest attributed to topical pharyngeal anesthesia or intravenously administered diazepam (Valium). While confirming the prevailing safety of peroral endoscopy and dilation, this survey points up the need for unremitting vigilance. Radiographic examination, when feasible, should precede peroral endoscopy. Any suspicion of perforation requires prompt radiologic investigation using a water-soluble contrast medium. Biopsy at the base of an ulcer is hazardous. Cardiopulmonary resuscitation should be immediately available in the endoscopy room. Pneumatic dilation of the esophagus carries a small but definite risk of rupture which necessitates emergency thoracotomy.

Colonic polyposis is a common complication of schistosomiasis in Egypt and is associated with significant morbidity and mortality. Recent studies have shown that niridazol (Ambilhar, Ciba Pharmaceutical Company, Summit, N. J.) is an effective therapeutic agent in this condition and may be associated with polyp regression. The purpose of this study was to evaluate, by direct visual inspection and biopsy, the effect of medical therapy in patients with schistosomal colonic polyposis. Pretreatment evaluation included physical examination, laboratory studies, stool parasitology, colonoscopy, and colon biopsy. All patients were treated with niridazol (25 mg per kg per day for 10 days), and posttreatment studies were completed at 3, 6, and 12 months. By 12 months, all patients were symptom-free, and there was marked improvement in physical status, laboratory studies, barium enema, and colonoscopy. These data support the efficacy of medical treatment in this condition and indicate that polyposis may be a reversible lesion.

The primary function of the lower esophageal sphincter is to prevent reflux of gastric contents into the esophagus. Therefore, changes in lower esophageal sphincter strength after the ingestion of various foods should be of considerable interest. Pressure in the lower esophageal sphincter was recorded continuously in normal subjects using an infused open-tipped system. Test meals consisted of equicaloric quantities of either protein, carbohydrate, or fat in a total volume of 150 cc. After ingestion of ground beef, consistent increases in lower esophageal sphincter pressure were recorded. This effect was eradicated by acidifying the ground meat meal to a pH of 1.2 to 1.3. After glucose ingestion, slight but significant increases in lower esophageal sphincter pressure were found. By contrast, ingestion of a corn oil meal resulted in a decrease in lower esophageal sphincter pressure. Even greater decreases in lower esophageal sphincter were produced by intraduodenal fat. Intraduodenal acidification and exogenous secretin resulted in minimal decreases in sphincter pressure, with much greater decreases in pressure noted after subsequent intraduodenal instillation of fat. The increased pressure after protein and its inhibition by acidification suggest a mechanism through antral gastrin release; the slight rise in pressure after glucose may indicate a minimal gastrin effect, and the pressure decreases following a fat meal most likely are produced by an entero- gastrone other than secretin.

Esophagogastroduodenoscopy (211,410 examinations) had a complication rate of 1.3/1,000 cases. Duodenoscopy with cannulation was performed 3,884 times and had a complication rate of 21.6/1,000 examinations. Diagnostic coloscopy (25,298 examinations) had a complication rate of 3.4/1,000. Polypectomies during coloscopy (6,124 cases) had a complication rate of 23.3/1,000 cases. Esophageal dilations (13,139 cases) had a complication rate of 4.25 with mercury bougies, and in 9,431 cases metal olives produced a complication rate of 6.1/1,000 treatments. Dilation for achalasia in 1,224 patients produced a complication rate of 18.4/1,000 procedures. Peritoneoscopy (4,404 examinations) produced a complication rate of 5.4/1,000 patients. The value of these diagnostic and therapeutic procedures is now well established but must be weighed against a potential risk of complications. ( JAMA 235:928-930, 1976)

Sphincter of Oddi pressure (SOP) was measured in 50 consecutive patients referred for evaluation of acute pancreatitis (15 patients), recurrent pancreatitis (21 patients), and postcholecystectomy syndrome (14 patients). The mean SOP (±standard error) in the patients with acute pancreatitis (40 ± 4 mm Hg) and recurrent pancreatitis (50 ± 6 mmHg) was significantly greater (P .05) than that of normal control subjects (31 ± 2 mm Hg). The clinical efficacy of this new procedure remains to be determined.

The endoscopic and histologic characteristics of active schistosomal colonic polyposis were studied in 10 Egyptian farmers with this condition. The endoscopic appearance and direct examination of the endoscopic biopsy specimen for viable schistosoma eggs allows rapid, reliable differentiation of colonic schistosomiasis from other forms of multiple colonic polyposis.

Manometric recordings were obtained using a single lumen perfused catheter that was inserted by duodenoscopy into the orifice of the papilla of Vater. Using duodenal pressure as a zero reference, a high pressure zone located just within the papilla of Vater was recorded in all subjects. Intravenous diazepam produced no significant change in sphincter pressure. Sphincter pressures measured in 20 subjects with no recognizable pancreatic or biliary disease ranged from 15mm to 43mm Hg with a mean pressure of 31±2mm Hg (± SE). These data indicate that there is a physiologic high pressure zone in the region of the papilla of Vater. The importance of this sphincter in health and disease remains to be evaluated.

Lower esophageal sphincter (LES) function in cirrhosis was evaluated using an infused manometric system. LES pressure (LESP) in 10 subjects with cirrhosis (22 +/- 1 mm Hg) (mean +/- SE) was not significantly (P greater than 0.05) different from that of 10 control subjects (21 +/- 1 mm Hg) but was significantly (P less than 0.01) greater than the LESP recorded in 5 subjects with cirrhosis and ascites (16 +/- 2 mm Hg). There was no significant difference in LES response to intravenous pentagastrin, intravenous edrophonium, or straight-leg raising in the three groups. After loss of ascitic fluid, LESP significantly (P less than 0.01) increased (deltaP : 9 +/- 3 mm Hg) and gastric pressure (GP) significantly (P less than 0.01) decreased (deltaP: 8 +/- 2 mm Hg). The changes in LESP and GP revealed a significant (R = 0.83, P less than 0.001) linear correlation. These data indicate (1) cirrhosis is associated with normal LES function, and (2) the mechanism of lowered LESP with ascites may be the inability of the LES to maintain a sustained response to chronic increases in GP.

The incidence and precipitating factors associated with symptomatic gastroesophageal reflux were evaluated by a questionnaire in 446 hospitalized and 558 nonhospitalized subjects. Of 385 control subjects 7% experienced heartburn daily, 14% noted heartburn weekly, and 15% experienced it once a month, giving a total of 36% of subjects having heartburn at least monthly. Daily heartburn occurred at a significantly greater (P less than 0.05) rate for 246 medical inpatients (14%) and for 121 patients seen in outpatient gastroenterological clinic (15%). Pregnant women seen in uncomplicated obstetrical clinic had symptoms of significantly greater (P less than 0.01) incidence: daily (25%) and at least once monthly (52%). Age, sex, or hospitalization did not significantly affect incidence. Fried foods, "spicy" foods, and alcohol were the most common precipitating factors.

Recent advances in fiberoptic instrumentation permit direct observation of the duodenum and cannulation of the ampulla of Vater with pancreatocholangiography in essentially all cases. An analysis of this technique in 252 consecutive patients with pancreatobiliary symptoms reveals that it is a safe and effective technique that may add significant new information in the evaluation of these patients.

Based on a comparison of duodenoscopy and upper gastrointestinal radiography in 150 symptomatic patients, the authors conclude that endoscopy provides new and significant diagnostic information.