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Background Irritable bowel syndrome (IBS) is a common abdominal pain disorder without an organic explanation. Abuse histories (physical, sexual, emotional) are prevalent in IBS. While abuse relates to mood disorders (depression and anxiety) also common in IBS, the influence of abuse on gastrointestinal (GI) symptoms and health-related quality of life (HRQOL) and its independence from psychological symptom comorbidity has not been studied. Methods Consecutive GI outpatients completed the ROME III Research Diagnostic Questionnaire and questionnaires on trauma (Life-Stress Questionnaire), mood (Beck Depression/Anxiety Inventories), somatic symptoms (PHQ-12), and HRQOL (SF-36). Current GI symptom severity and bother were assessed using 10-cm Visual Analog Scales. Key Results 272 ROME-defined IBS (47.6 ± 0.9 years, 81% female) and 246 non-FGID (51.6 ± 1.0 years, 65% female) subjects participated. IBS patients reported greater rates of physical, sexual, and emotional abuse (p < 0.006 each), and higher depression, anxiety, and somatic symptoms (p < 0.001). Greater bowel symptom bother (7.4 ± 0.2 vs 6.7 ± 0.2, p = 0.040), severity (7.7 ± 0.2 vs 6.5 ± 0.2, p < 0.001), recent symptomatic days (9.8 ± 0.4 vs 8.5 ± 0.3, p = 0.02), and poorer HRQOL (40.9 ± 2.3 vs 55.5 ± 1.7, p < 0.001) were noted in IBS with abuse. Abuse effects were additive, with greater IBS symptom severity and poorer HRQOL noted in cases with multiple forms of abuse. Mediation analyses suggested that abuse effects on GI symptoms and HRQOL were partially mediated by mood. Conclusions & Inferences Abuse experiences common among IBS sufferers are associated with reports of greater GI symptoms and poorer HRQOL, particularly in those with multiple forms of abuse; this relationship may be partially mediated by concomitant mood disturbances.

Nuclear magnetism in the second layer of 3He films on graphite has been studied as a function of density in the zero-field limit at temperatures down to 300 µK. Total surface coverages in this study ranged from 20 atoms/nm2 (the lowest coverage at which the effective exchange parameter turns ferromagnetic) through the two-phase region (ending at about 24 atoms/nm2) and into the single-phase imcommensurate solid region up to 31.2 atoms/nm2. The surface layers were studied using both pulsed and cw NMR measured with our SQUID NMR system in magnetic fields of 500 µT and lower. As the surface density continues to increase in the single-phase region, the exchange constant decreases consistently with a picture of steric hindrance impeding ferromagnetic exchange. Several different observational features scale with this inferred exchange: low-field magnetization, NMR frequency shift, and the temperature of onset of significant magnetization.

We report measurements of the magnetic susceptibility of liquid 3He at saturated vapor pressure in the normal state from the superfluid transition temperature up to 1 K. Our results are comparable to those of Ramm, et al.1 at temperatures above 200 mK, but are systematically higher as T→0. We conclude that the zero-temperature limiting susceptibility is approximately 5.9% larger than reported by Ramm, et al. Consequently, the discrepancy in the liquid's diamagnetism between values expected theoretically and our experimentally measured results is essentially eliminated.

We measure the magnetic susceptibility of a group of materials commonly used in the construction of low temperature cryostats. These materials are considered non-magnetic at room temperature. We use a variable temperature susceptometer to measure samples at temperatures between 2.0 K and 12.0 K and at magnetic fields between 0.25 Tesla and 4 Tesla. The samples we use include Aluminum, Beryllium Copper, fused silica, Grafoil, stainless steel, filled and unfilled epoxy, Macor, polycarbonate, aerogel, silver powder, Teflon, and Vespel. We present plots of the magnetization vs. temperature and field, and a table of the parameters to a fitting function which can be used to interpolate the data.

3 He films on graphite provide a model system for 2D magnetism. At low temperatures, the thermodynamic properties of these films are dominated by exchange interactions. However more subtle interactions such as dipolar coupling and other anisotropies may eventually play a substantial role, especially in small magnetic fields. Our recent experiments use a SQUID system for both pulsed and continuous wave NMR at very low applied fields (B

We have measured the absolute thermodynamic magnetization of 3 He in all of its liquid phases while using a new calibration technique which relies on the nuclear paramagnetism over the entire temperature range below 1 K as measured by Ramm, et al. We have directly measured the temperature dependence separately of the nuclear paramagnetism via NMR and of the total magnetism via our free-surface modulation technique. We report substantial agreement with Ramm, et al. In consequence, we find that the diamagnetism of liquid 3 He is significantly smaller than expected theoretically, a condensed matter effect not seen previously. We have also remeasured the magnitude of the magnetization discontinuity at the superfluid A-B transition and find close agreement at saturated vapor pressure with NMR-deduced values from Scholz.

PURPOSE: To compare conventional short inversion time inversion-recovery (STIR) with fast spin-echo (FSE) STIR techniques to evaluate suspected nontraumatic musculoskeletal abnormalities. MATERIALS AND METHODS: Thirty STIR and FSE-STIR examinations in 26 pediatric patients with suspected nontraumatic musculoskeletal abnormalities were prospectively evaluated. Qualitative (subjective) and quantitative (five-point rank score) analyses of the images were performed. RESULTS: FSE-STIR was faster than STIR (mean, 2 minutes 25 seconds and 6 minutes 35 seconds, respectively). Fat suppression was slightly better with STIR. Image degradation due to motion was judged similar. Lesion contrast to muscle was slightly better with STIR than FSE-STIR, and lesion contrast to fat was equivalent. Qualitatively, lesion conspicuity was similar: All lesions were seen with both techniques. CONCLUSION: FSE-STIR can replace STIR when an inversion-recovery fat-suppression sequence is desired. Considerable imaging time is saved.

Nephroblastomatosis is an abnormality of nephrogenesis characterized by incomplete maturation of primitive nephrogenic cells. The resultant individual lesions have variable histologic findings and distribution in the kidney. There is wide acceptance of nephroblastomatosis as a precursor lesion to Wilms tumor. Consequently, the role of imaging in assessing patients for neoplastic transformation of nephroblastomatosis should be emphasized. Computed tomography (CT) has been shown to be superior to ultrasound (US) in this regard. Nonetheless, the low cost and lack of radiation of US make it attractive for serial screening studies. Although magnetic resonance imaging shows promise in assessment of the kidney for nephrogenic rests, experience is limited in its use in evaluating patients for nephroblastomatosis. The authors present protocols for assessing patients identified as being at either high or low risk for the development of Wilms tumor due to nephroblastomatosis. These protocols take into account the advantages of CT and US. Scanning intervals are determined from epidemiologic data on the occurrence of Wilms tumor; the most intense screening occurs during the younger ages of life, when the likelihood of Wilms tumor development is highest.

Spirometric measurement of lung volume in an infant or uncooperative child is often a difficult and time-consuming procedure. Previous investigators have successfully estimated total lung capacity in adults and older children by using chest radiography. The purpose of this study was to assess the accuracy of functional residual capacity (FRC) determination from chest radiographs in an animal model of the normal neonatal chest. FRC was determined with the helium dilution (HeD) method in 13 anesthetized, intubated, and paralyzed rabbits (weight range, 1.5-3.9 kg). FRC was then estimated from digital frontal and lateral chest radiographs. The radiographic estimate was made by applying measurements taken from the radiographic film pair to a geometric model of the chest. The best-fit model assumed an elliptical cross section for the intrathoracic cavity, heart, paraspinal structures, and diaphragm in the axial plane. Linear regression on independently determined HeD and radiographically determined FRC yielded a slope of 1.02 (p less than .001), an intercept of -3.02 cm3 (p = .565), and a correlation coefficient of 0.96 (p less than .001). We conclude that radiographic FRC estimates closely approximate HeD estimates in a rabbit model of the normal neonatal chest.

Sepsis after splenectomy is a lifelong risk, and patients who have had splenectomy should be educated about this risk. This study examines patient knowledge after splenectomy. We reviewed hospital records of 118 patients who had splenectomies performed between 1982 and 1988 at New Hanover Memorial Hospital. Twenty-four patients have died since their surgery; one death was suspected to be due to postsplenectomy sepsis. Of the 89 patients alive and eligible for follow-up, we were able to query 63. Only 16% were aware of any health precautions. After prompting, patient awareness improved to 40%. We also surveyed 11 of the 14 surgeons who performed the splenectomies. They indicated that they always discuss with their patients the immunologic consequences of spleen removal and the increased risks of infection, although they do not always recommend pneumococcal vaccine. We conclude that splenectomy patients have a low level of knowledge about postsplenectomy infection risks and precautions. We developed an educational pamphlet to aid the surgeon in patient education.

Paraquat is one of the few broad-spectrum herbicides available in the US; however, it is extremely toxic to companion animals when ingested. Despite its restricted use status, poisoning of dogs and cats remains relatively common. This clinical report documents a series of chronologically and geographically related cases of presumed malicious and fatal sub-acute paraquat poisoning in 7 dogs in Portland, OR. All animals developed acute gastrointestinal disturbance, renal compromise and insidiously progressive respiratory failure. Hyperlipasemia and moderate hypertension were notable featured in 5/7 cases. Trace levels of paraquat were demonstrated in the urine of 4/7 animals by gas-liquid chromatography/mass spectroscopy. Diagnosis in the remaining 3 cases was made through a combination of history or exposure, clinical signs and their progression, and pulmonary and renal histopathology.

Since 15 July 1993, we have used helical CT exclusively in chest and abdomen exams. The purpose of this study was to compare sedation rates in children undergoing conventional and helical CT of the chest and abdomen. Data for all CT examinations of the head (n = 1121), chest (n = 427), and abdomen (n = 315) performed between 1 April 1993 and 31 October 1993 were evaluated. Examinations were divided by anatomic site, patient age, date, whether motion was noted in the radiology report, and whether or not sedation was used. The oldest patient requiring sedation was 5 years old. All examinations in patients 5 years old or less (n = 1048) formed the study group. Because no head CT examinations were done helically, this constituted a control group. Comparisons of motion and sedation rates before and after 15 July 1993 were made with the chi 2 test. There was no statistically significant difference in the sedation rate in the control group (patients having conventional head CT examinations). In contrast, the use of helical technique for chest and abdomen CT coincided with a reduction of the sedation rate from 18% to 10% (P = 0.3). There was no statistically significant difference in reported motion for either head or chest/abdomen examinations over the study period. The implementation of helical CT coincided with a 45% reduction in the sedation rate of patients undergoing CT of the chest and abdomen. At the current volume of CT examinations at our institution, this decrease would result in an estimated 60 fewer sedations per year.

The objective of this study was to compare the quality of conventional and helical computed tomography (CT) images in children unable to breath-hold. Sixteen patients (age range 1.1–7.5 years) underwent both conventional and helical chest CT on a General Electric HiSpeed Advantage scanner at a mean study interval of 3.8 months. Conventional 0.6-s scans were reconstructed with standard algorithm while 1.0-s helical studies were reconstructed with standard and bone algorithms. Three blinded observers retrospectively evaluated the images. There was no significant difference in motion, image sharpness and anatomic resolution for helical and concentional scans reconstructed with standard algorithm. Furthermore, image sharpness (P

We provide evidence for a finite-temperature ferromagnetic transition in two dimensions as $H\ensuremath{\rightarrow}0$ in thin films of ${}^{3}\mathrm{He}$ on graphite, a model system for the study of two-dimensional magnetism. We perform pulsed and cw NMR experiments at fields of 0.03--0.48 mT on ${}^{3}\mathrm{He}$ at areal densities of $20.5--24.2\mathrm{atoms}/{\mathrm{nm}}^{2}$. At these densities, the second layer of ${}^{3}\mathrm{He}$ has a strongly ferromagnetic tendency. With decreasing temperature, we find a rapid onset of magnetization that becomes independent of the applied field at temperatures in the vicinity of 1 mK. Both the dipolar field and the NMR linewidth grow rapidly as well, which is consistent with a large (order unity) polarization of the ${}^{3}\mathrm{He}$ spins.

We provide evidence for a finite-temperature ferromagnetic transition in two dimensions as H --0 in thin films of 3He on graphite, a model system for the study of two-dimensional magnetism. We perform pulsed and cw NMR experiments at fields of 0.03-0.48 mT on 3He at areal densities of 20.5-24.2 atoms/nm(2). At these densities, the second layer of 3He has a strongly ferromagnetic tendency. With decreasing temperature, we find a rapid onset of magnetization that becomes independent of the applied field at temperatures in the vicinity of 1 mK. Both the dipolar field and the NMR linewidth grow rapidly as well, which is consistent with a large (order unity) polarization of the 3He spins.

The Revised Children's Manifest Anxiety Scale (RCMAS; C. R. ReynoldsB. O. Richmond, 1985) is among the most widely used self-report measures of children's anxiety. The authors compared its current empirically derived factor structure with theory-driven models derived from 8 experts on child anxiety using concept mapping. Confirmatory factor analyses compared models using data from 898 seventh graders in an urban public school system serving a high percentage of African Americans. The most parsimonious best-fitting model was an expert-derived model with factors reflecting anxious arousal, social evaluation-oversensitivity, worry, and a higher order factor. This model was theoretically meaningful, excluded items less relevant to anxiety, and was invariant across gender. Future research with the RCMAS should consider use of these dimensions. The combination of qualitative and quantitative methodology used in this study appeared to have considerable utility for refining measures.

Thomas Jefferson National Accelerator Facility's (Jefferson Lab) accelerator controls were initially implemented as a proprietary in-house system. During machine commissioning, problems were encountered leading to a decision to migrate to the Experimental Physics and Industrial Controls System (EPICS). Since then, the accelerator and all other laboratory controls have been successfully converted. In addition to implementing Jefferson Lab's controls using EPICS, new data visualization tools have been developed and existing programs have been enhanced with new capabilities. In order to provide a more generic interface for high level applications development, a device abstraction layer, called Common DEVice (CDEV), was implemented. These additions have been made available to other laboratories and are in use at many sites, including some that do not use EPICS. Control System development is not limited to computer scientists; operators, engineers and physicists frequently add capabilities using EPICS, CDEV, Tel/tk, and other tools. These contributions have tailored the control system for many different types of customers. For the future, the authors envision more intelligent processing and more capable tools for data storage, retrieval and visualization.

The objective was to evaluate the CT imaging appearance, distribution of disease, type of immunocompromised state, and outcome of children with Epstein-Barr virus-induced lymphoproliferative disorders.Medical records and imaging studies (from four tertiary children's medical centers) were reviewed for pathologically proven cases of lymphoproliferative disorders in patients less than 20 years old. Trends between the CT imaging appearance, distribution, and type of immunocompromised state and prognosis were noted and analyzed with Fisher's exact test.Twenty-seven cases were identified (mean age, 7 years 8 months). Eighteen children had undergone solid organ transplantation (heart, n = 9; liver, n = 7; kidney, n = 2), and four had undergone bone marrow transplantation. Five patients had primary immunodeficiencies. The CT appearance of lymphoproliferative disorders varied and included lymphadenopathy, focal mass or masses, and diffuse infiltration and enlargement of organs without focal mass. The distribution of disease included abdomen (n = 17), chest (n = 10), neck (n = 8), and brain (n = 1). In eight of nine heart transplant recipients, the disease predominantly involved the chest and neck, whereas in all seven liver transplant recipients, the disease was isolated to the abdomen (p = .001). The overall mortality rate of 44% was less related to anatomic extent (multiorgan, 46%; localized, 43%) than to type of immune dysfunction (p = .001): bone marrow transplantation (100%), primary immunodeficiency (80%), heart transplantation (55%), liver transplantation (0%), and kidney transplantation (0%).Lymphoproliferative disorders in children had a variable distribution, imaging appearance, and outcome. However, in recipients of solid organ transplants, the disease tended to occur in the anatomic region of the transplant. Mortality rates were more closely related to the type of underlying immune dysfunction than to distribution of disease.

The moderating influences of family structure and parent-adolescent distress on the relationship between peer variables and drug use were examined in a predominantly African American sample of 630 10th graders at 9 urban high schools. Both peer pressure and peer drug use were significantly related to the reported frequency of drug use. The relationship between peer pressure and drug use was stronger among girls than boys, and also among adolescents in families without fathers or stepfathers. The association between peer pressure and drug use also increased as a function of the level of mother-adolescent distress among adolescents who were not living with fathers or stepfathers. Neither gender nor family structure moderated the relationship between peer drug models and drug use. However, the association between peer drug models and drug use increased as a function of the level of mother-adolescent distress.

Systemic oxygenation is improved by inhaled nitric oxide therapy in some newborns with respiratory failure and pulmonary hypertension. Our results with inhaled nitric oxide were reviewed to determine factors associated with an acute improvement in systemic oxygenation.Newborns with oxygenation indices of 25 to 40 were prospectively randomized to receive conventional therapy with or without 20 ppm inhaled nitric oxide. All newborns with oxygenation indices greater than 40 were treated with inhaled nitric oxide. Hemodynamic, blood gas, and Doppler ultrasound measurements were performed before and after 30 to 60 minutes of observation or therapy. The severity of lung disease was classified by the chest radiograph as: (1) normal or focal disease; (2) moderate diffuse disease-diffuse lung disease with well-defined heart borders; or (3) severe diffuse disease-diffuse lung opacification with indistinct heart borders.Heart rate, blood pressure, and ductal diameters did not change. Blood gases and ductal shunting acutely improved only in patients treated with inhaled nitric oxide. Patients with normal lung fields or focal disease had the greatest degree of improvement in systemic oxygenation. Changes in oxygenation were not influenced by gestational age, baseline blood gases, the proportion of right-to-left ductal shunting, prior treatment with a surfactant, or the use of conventional or high-frequency jet ventilation. Collectively, blood gases and ductal shunting did not improve with inhaled nitric oxide in patients with lung hypoplasia or severe diffuse lung disease. Sustained improvement in oxygenation occurred in 87% of patients with oxygenation indices greater than 40 in whom oxygenation indices less than 40 acutely developed after exposure to nitric oxide, whereas 90% of patients in whom oxygenation indices less than 40 did not acutely develop were treated with extracorporeal membrane oxygenation or ultimately died.Inhaled nitric oxide acutely improves systemic oxygenation in many newborns with respiratory failure and pulmonary hypertension. The diagnosis and chest radiograph are helpful in identifying patients who will have favorable acute responses to therapy. In patients with severe hypoxemia, the need for invasive support with extracorporeal membrane oxygenation may be determined by an acute trial of inhaled nitric oxide.

Granulocyte colony-stimulating factor (GCSF) is used to stimulate myeloid cell production and function in children undergoing chemotherapy for osteosarcoma. We hypothesize that GCSF can cause reconversion of marrow from fatty to hematopoietic and that this change can be detected by MR imaging at sites away from the primary tumor. This benign effect of treatment should not be confused with tumor spread.MR images of marrow of the affected and contralateral limbs were retrospectively reviewed for 16 patients with osteosarcoma of the femur or tibia; nine of these patients had received GCSF. A grade was assigned to marrow signal intensity at sites away from the tumor, and findings before and after treatment were compared. The validity of MR image interpretation was assessed by comparing the signal intensity of marrow with the histologic appearance of marrow at 19 resection margins.Changes consistent with reconversion were seen on MR images in seven of nine patients who had received GCSF in addition to chemotherapy and in none of seven patients who had received chemotherapy alone. The difference in proportions was statistically significant (p = .006; Fisher's exact test, two tailed). The histologic appearance of marrow at the resection margins agreed with the interpretation of the short-Tl inversion recovery sequence in all cases (100%).The findings suggest that GCSF causes changes in the MR imaging appearance of marrow. Histologic correlation supports the hypothesis that these changes are attributable to reconversion from fatty to hematopoietic marrow. Awareness of this finding is important to avoid false-positive diagnosis of marrow metastases.

PURPOSE: To evaluate changes in vertebral marrow signal intensity that occur over time in children undergoing craniospinal radiation therapy, specifically evaluating for the occurrence and timing of marrow regeneration. METHODS: MR images of nine pediatric patients (ages 4 to 12 years) with posterior fossa medulloblastoma who received total spinal irradiation (24 to 40 Gy) and had at least three MR examinations were reviewed. Signal intensity to vertebral body marrow was graded by two pediatric neuroradiologists who were blinded to patient identity and to the timing of the studies. RESULTS: Eight of nine patients demonstrated increasing signal intensity of the vertebral marrow after irradiation, consistent with conversion of hematopoietic to fatty marrow. In each of these patients, this was followed by subsequent decreasing signal intensity in a mottled or peripheral band pattern indicating recovery of hematopoietic marrow. CONCLUSION: Changes in vertebral body signal intensity consistent with marrow reconversion commonly are seen in pediatric patients 11 to 30 months after they undergo total spinal irradiation.

We use SQUID NMR to observe the magnetization of 3 He films with densities between 20 and 24 atoms / nm 2 in the zero field limit. Ferromagnetism in these nearly 2D Heisenberg exchange systems is stabilized by weak anisotropies. In the ferromagnetic phase, the NMR line becomes very broad and shifts to lower frequencies, consistent with a large dipolar field opposing a perpendicular applied field. Grafoil can be modeled by a Gaussian distribution of platelet angles centered on the normal to the Grafoil plus a randomly distributed set of platelets. Using the spin dynamics of a 2D polarized sheet with reasonable assumptions for the distributions of platelet angles, we show that the magnetization, frequency shift and line shape form a consistent picture of a highly polarized sheet.

Conflicting results between different laboratories of measurements of the phase diagram of superfluid 3 He when immersed in aerogel, even with nominally identical aerogels, suggest that details of the aerogels other than the porosity are important in determining superfluid properties. We have simulated the growth of small clusters ðNB10 5 Þ by offlattice single-particle diffusion limited aggregation (DLA). Measurements of the free-path distribution function of 3 He quasiparticles scattered by these clusters—truncated and repeated to simulate experimental conditions—show significant differences from uncorrelated scatterers at the same density, which differences may be significant for superfluid properties. r 2003 Elsevier Science B.V. All rights reserved.

Interventricular septal defect following nonpenetrating trauma is a rare event. In a review of 207,548 autopsies, only 30 (0.01%) cases of traumatic ventricular septal defects were noted, and only 5 (0.002%) were isolated. We report an isolated interventricular septal defect following nonpenetrating trauma.

Measurement of the atlas-dens interval is the radiographic standard for identification of patients with Down syndrome at high risk for neurologic injury from spinal cord compression. In 17 pediatric patients with Down syndrome, measurements of the atlas-dens interval, distance between the clivus and posterior odontoid process, and width of the neural canal obtained with plain radiographs were compared to predict the width of the subarachnoid space on magnetic resonance (MR) images. In all patients, cervical radiography and craniocervical MR imaging were prospectively performed during lateral flexion and extension. The width of the subarachnoid space was measured with MR imaging. When the 95% confidence interval for correlation coefficients of regression was used, subarachnoid space width on MR images correlated with neural canal width on radiographs better than with either atlas-dens interval or clivus-posterior odontoid process distance (P = .05). Measurement of neural canal width is a better predictor of potential spinal cord compression than the atlas-dens interval or clivus-posterior odontoid process distance and should be emphasized in screening examinations performed with plain radiography.

Abdominal imaging has undergone extensive change over the past several years. In many cases, the developments have been so rapid as to preclude an orderly comparison of competing procedures with prospective comparison studies. Consequently, no rigid imaging protocol will be universally accepted and many issues are unresolved. This article reviews the various imaging procedures used in imaging pediatric abdominal masses with emphasis on technique, indications, risks, and costs. The relative merits of imaging modalities in various clinical situations are outlined and specific recommendations are given.

We have measured the absolute magnetization of liquid 3He at saturated vapor pressure over the temperature range 0.3–500 mK. The technique compares the magnetization of the liquid to that of vacuum by passing the liquid–vacuum interface through a SQUID coil. We find that, contrary to expectations, the electronic diamagnetism of the normal liquid is approximately 6% less than the calculated atomic value. This appears to be the first measurement of the diamagnetic susceptibility of any noble gas in a condensed state.

3He films on graphite at densities above 20 atoms / nm 2 have a strong ferromagnetic tendency. Models of multiple spin exchange are believed to describe the dominant interaction. However, other much smaller interactions can significantly alter the low-temperature behavior of these systems, especially in very low magnetic fields. Our recent experiments have used a SQUID system for both pulsed and continuous wave NMR at very low applied fields (B mT ) . Our results show that the polarization of this system grows much more rapidly than is expected from the Heisenberg exchange models, even approaching saturation. Possible explanations are the influence of finite size effects and dipolar interactions.

The use of a SQUID coupled to a sample by a superconducting circuit allows NMR measurements over wide bandwidths. For our recent NMR experiments on 3He monolayers we developed a sample cell that allows for indirect cooling of the grafoil without excessive eddy currents. The details of the cell design are discussed. In addition, we have found that the 13C signal from the graphite is observable in this system. The FID time constant for this signal is comparable to the field homogeneity and the amplitude follows the Curie law over our temperature range ( 15 mK >T>0.2 mK ). Since the NMR signal in 13C is observed simultaneously with the 3He signal, this signal can act as a thermometer for the graphite substrate.

Sepsis after splenectomy is a lifelong risk, and patients who have had splenectomy should be educated about this risk. This study examines patient knowledge after splenectomy. We reviewed hospital records of 118 patients who had splenectomies performed between 1982 and 1988 at New Hanover Memorial Hospital. Twenty-four patients have died since their surgery; one death was suspected to be due to postsplenectomy sepsis. Of the 89 patients alive and eligible for follow-up, we were able to query 63. Only 16% were aware of any health precautions. After prompting, patient awareness improved to 40%. We also surveyed 11 of the 14 surgeons who performed the splenectomies. They indicated that they always discuss with their patients the immunologic consequences of spleen removal and the increased risks of infection, although they do not always recommend pneumococcal vaccine. We conclude that splenectomy patients have a low level of knowledge about postsplenectomy infection risks and precautions. We developed an educational pamphlet to aid the surgeon in patient education.

The contribution of amiloride-sensitive membrane components to the perception of NaCl taste was assessed by using a conditioned taste aversion procedure. Eight independent groups of adult rats were conditioned to avoid either 0.1M NaCl, 0.5M NaCl; 0.1M NH4Cl, or 1.0M sucrose while their tongues were exposed either to water or to the sodium transport blocker amiloride hydrochloride. In contrast to rats exposed to water during conditioning, rats exposed to amiloride were unable to acquire a conditioned taste aversion to 0.1M NaCl. Differences in the acquisition of taste aversions between the amiloride- and nonamiloride-treated groups were not apparent when the conditioned stimulus (CS) was 0.5M NaCl, 0.1M NH4Cl, or 1.0M sucrose. Although the magnitude of the 0.5M NaCl aversion was similar between amiloride- and non-amiloride-treated rats, the perceptual characteristics of the CS differed between groups. Analyses of stimulus generalization gradients revealed that amiloride-treated rats generally avoided all monochloride salts after conditioning to 0.5M NaCl but not nonsodium salts or nonsalt stimuli. In contrast, rats not treated with amiloride only generalized the 0.5M NaCl aversion to sodium salts. No differences in generalization gradients occurred between groups when the CS was 0.1M NH4Cl or 1.0M sucrose. These findings suggest that the "salty" taste of NaCl is primarily related to the amiloride-sensitive portion of the functional taste response in rats. Conversely, the portion of the NaCl response insensitive to amiloride appears to have "sour-salty" perceptual characteristics and does not appear to be perceived as being salty.

Outdoor reared pigs are said to suffer from less of a growth check post weaning than their indoor reared counterparts, Payne et.al (2003). Zinc oxide (ZnO) is often used to reduce the incidence of post weaning scours and the use of sodium butyrate as an additive in weaner pig diets has been shown to improve some aspects of small intestine structure (Miller et.al, 2006). The purpose of this experiment was to investigate the effects of butyrate supplemented weaner diets with or without a ZnO background (3.1 or 0g/kg ZnO) upon gut structure immediately post weaning in both indoor and outdoor reared pigs. We hypothesised that piglets reared outside would have a more developed gut than indoor reared pigs when weaned at 4 weeks and that the presence of ZnO and butyrate would further enhance gut development.

A simple optical-lever amplifier constructed from components normally available in a university physics department is described. The design was based on one by Jones, but was modified so that it could be built by a final-year undergraduate. The amplifier was used to study the Brownian motion of a galvanometer. From this study, the value of Boltzmann's constant k was found to be (1.46±0.1) × 10−23J°K−1, the accepted value being 1.38 × 10−23J°K−1.

Quasi-periodic 12.5-min fluctuations occurred in the counting rates of Geiger counters and a neutron counter during level flight of a balloon over Wilkes, Antarctica, on September 3, 1966. Correlated fluctuations were observed in the Wilkes magnetometer record. A large solar cosmic-ray event was in progress at the time of the flight. The periodic modulation process is shown to have an energy dependence with a peak at about 50 Mev for solar protons. No periodicity was detected in the Geiger counter telescope rate, which had a proton threshold energy of > 110 Mev. It is suggested that the modulation is a result of scattering by hydromagnetic waves in the distant part of the tail. The protons with E > 110 Mev did not pass through the modulating region and probably gained access to the magnetosphere on the dayside.

A large increase in the atmospheric neutron flux was observed at balloon altitudes on September 3, 1966, during a solar proton event. The flux and energy spectrum of the solar particles are known with some precision from satellite detectors, as well as from our balloon measurements. From these data quantitative comparisons have been made with the predictions of Lingenfelter and Flamm (1964) on the production of neutrons in the atmosphere by proton interactions. The theory is in satisfactory agreement with the observations, although there is considerable uncertainty about the fraction of neutrons that leaked out of the atmosphere.

We reviewed 12 cases of chronic renal failure in patients with secondary hyperparathyroidism who had total parathyroidectomy and forearm autotransplantation during the years 1978 to 1984. All had elevated parathyroid hormone and calcium levels before the procedure. Using a technique previously described, with relatively large parathyroid grafts in the forearm, calcium levels were effectively reduced and maintained below the upper limit of the normal range (10.5 mg/dl). Only one patient had symptomatic hypocalcemia postoperatively. Phosphorous levels were also significantly reduced to more physiologic values. When necessary, the forearm autografts allowed simplified titration of calcium levels on an outpatient basis.

The plasma level of naturally acquired inhibitors to clotting Factor VIII activity (F.VIII: C) was assessed by the Bethesda Inhibitor Assay (BIA). At inhibitor concentrations outside the BIA working range (25% to 75% residual F.VIII: C), patient plasmas had to be diluted. However, when a rough estimate of the inhibitor concentration was unavailable, the choice of dilution was arbitrary and testing became tedious and inefficient. In an effort to improve the BIA, a screening test was devised to predict the appropriate plasma dilution. It is based on the partial thromboplastin time (PTT) of the incubated sample and is performed just prior to preparing dilutions for the F.VIII: C assay. Test plasmas were diluted serially in multiples of two, from 1:2 to 1:1024, and then incubated according to the BIA. After 90 min, samples were removed for PTT determinations to screen for the appropriate dilution to use in the F.VIII: C assay. The first two test dilutions to produce PTT values 21 sec (± 4 sec, 95% confidence interval) greater than the control resulted in a residual F.VIII: C for the BIA within the 25% to 75% acceptable range. When the log ratio of patient-to-control PTT determinations (specific PTT) for a given dilution was plotted as a function of log residual F.VIII: C at that test dilution, in 81 Bethesda assays a linear relationship was observed (p> .25; with r2 = .81). The screening test was 89% effective in predicting an appropriate dilution (range 0 to 1020 Bethesda units/ml). The accuracy can be enhanced further if, based on the first of three dilution screen tests in which the specific PTT >21 sec, the F.VIII: C assay is performed using the middle dilution value first. Depending on whether that dilution yields an acceptable residual F.VIII: C, either the higher or lower dilution is chosen in the second F.VIII: C assay.

The purpose of this study was to determine if motivation to manage increased simultaneously with planned-for cognitive learning of management. A management course designed to stimulate cognitive learning was studied. It was presented to supervisors in hospital, independent, and public health laboratories. Two groups of 22 and 26 participants, respectively, were identified to be studied. Measures of cognition and motivation were taken before and after training. The analysis revealed statistically significant increases in cognitive learning in both study groups. The analysis of motivational data did not reveal a statistically significant increase in motivation to manage for either group. It was concluded that it is possible to stimulate cognitive learning of management if such learning is consciously planned. It was also concluded that under the experimental conditions, motivation to manage does not increase when it is treated as incidental to the planned-for cognitive learning.