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OBJECTIVE: To evaluate the accuracy of quantitative three dimensional echocardiography in patients with deformed left ventricles. DESIGN: Three dimensional and cross sectional echocardiographic estimates of left ventricular volume and ejection fraction were prospectively compared to those obtained from magnetic resonance imaging. SETTING: Echocardiography laboratory of a university hospital. PATIENTS: 26 patients (9 months to 42 years, median age 11 years) with pulmonary hypertension and fixed reversal of normal interventricular septal curvature. MAIN OUTCOME MEASURES: Left ventricular end diastolic and end systolic volumes and ejection fraction. RESULTS: Three dimensional echocardiographic comparison to magnetic resonance imaging (MRI) yielded r values of 0.94 and 0.87 with a bias of -6.9 (SD 6.9) ml and -16 (11.2) ml for systolic and diastolic volumes respectively. Inter-observer variability was minimal (8.3% and 7.6% respectively). Cross sectional echocardiography gave correlation coefficients of 0.62 and 0.80 and bias of 3.1 (14.1) ml and 16.3 (18.3) ml for systolic and diastolic volumes respectively. Ejection fraction by three dimensional echocardiography also had closer agreement with MRI (bias = 1.1 (7.7)%) than cross sectional echocardiography (bias = 4.4 (13.9)%). CONCLUSIONS: Three dimensional echocardiography provides reliable estimates of left ventricular volumes and ejection fraction, comparable to magnetic resonance imaging in pulmonary hypertension patients with compressed ventricular geometry. Because it eliminates the need for geometric assumptions it shows closer agreement with magnetic resonance imaging in that setting than cross sectional echocardiography.

Ultrasound images may be difficult to interpret because of the lack of an image orientation display. To resolve this problem, a three-dimensional (3-D) ultrasound scanner has been constructed that provides spatial registration and display of position and orientation of real-time images while allowing unconstrained movement of the scanning transducer. It consists of a conventional sector scanner, a 3-D acoustical spatial locater, and a personal computer. It displays within each image the line of intersection of two image planes, a reference image, and a live image. This display guides and documents image positioning. The scanner's 3-D data also provide the potential for computergraphic modeling of organs, the ability to calculate volumes using nonparallel, nonintersecting image planes, and the capability for 3-D color flow mapping and measurement of Doppler angle.

Individuals who have multiple sclerosis (MS) typically experience problems with physical activities such as walking, resulting from the combined effects of skeletal muscle weakness, sensory disturbances, spasticity, gait ataxia, and reduction in aerobic capacity. The aim of this study was to determine whether a 6-mo exercise program designed for aerobic conditioning might also affect gait abnormalities in individuals with MS. Subjects included 18 individuals with MS who presented a range of disability. Passive range of motion (PROM) in the lower limbs was measured and gait analyzed before and after exercise conditioning. Three-dimensional kinematics, ground reaction forces (GRF), and electromyographic information were acquired as subjects walked at self-selected velocities. Hip PROM increased following conditioning. Mean walking velocity, cadence, and posterior shear GRF (push-off force) decreased. During walking, maximum ankle dorsiflexion decreased and ankle plantarflexion increased. Total knee flexion/extension range during the walking cycle decreased slightly as did maximum hip extension. Results suggest this 6-mo training program had minimal effect on gait abnormalities.

McDermott Technology, Inc. (MTI) and Catalytica Advanced Technologies (CAT) have teamed to develop compact fuel processors for fuel cell electric vehicle applications. Electric vehicles, powered with proton exchange membrane (PEM) fuel cells operating on reformed liquid fuels such as gasoline are one of the key applications. MTI and CAT are developing a compact, autothermal fuel processor system designed for on-board vehicle operation. As part of this development we are evaluating various catalyst compositions and performing extensive catalyst characterization testing. In addition, proprietary liquid-phase, desulfurization technologies are being developed to facilitate removal of organically bound sulfur from gasoline. This work will be followed by a 20 kWe breadboard gasoline fuel processor demonstration. The 20 kWe system will demonstrate integrated performance and provide design validation necessary for testing of a compact 50 kWe fuel processor in 2001. This paper summarizes the status of work in the emerging technology of fuel processing for fuel cell powered electric vehicles.

There is evidence that one group is associated with assimilation among its parts and an increase in visibility (IV) of at least one of its parts: the 1 group-assimilation-IV position. The present research supports this position using physically identical stimuli, hence eliminating differences in features. This was accomplished by comparing the effects of large and small backgrounds on responding to physically identical stimuli that appeared on these backgrounds. Compared to the small background, the large background produced a stronger two-line group according to a closure measure of grouping, more assimilation between two lines according to a same-different measure of perceived similarity, and a greater IV of one of two lines according to context+target versus context relative to target versus background discriminations. The large background was much larger than the two small lines, suggesting that it functioned as an anchor.

Talon cusp may occur with other dental anomalies. A case is reported in which talon cusp is associated with a supernumerary tooth, suggesting genetic inheritance as a causative factor.

Posterior crossbite, the most common malocclusion in young children, can be caused by a variety of skeletal, muscular, or dental factors. This condition produces insufficient maxillary arch width and is frequently associated with various oral sucking and postural habits. If left untreated, this problem can result in adverse skeletal growth changes. Various mechanical treatment modalities designed to expand the posterior maxillary arch width are available to correct this problem. The appropriate treatment method depends on the patient's age and level of cooperation as well as the determined etiology of the constriction.

This review article examines supernumerary teeth as to prevalence, location, clinical and radiographic appearance, etiology, complications and management of supernumerary teeth; congenital absence of teeth as to prevalence and location, clinical features and complications, etiology, treatment considerations, and coexistance of supernumeraries and congenital absence of teeth.

The purpose of the present study was to investigate the effect of slope variations upon the maximal velocity attainable by cross-country ski racers using three skating techniques (V-1, V-2, and Gunde). Nine (2 females, 7 males) junior ski racers (16.0 +/- 0.4 yr of age, mean +/- SEM) exhibiting strong technical skills participated in the study. The subjects were required to skate at maximal velocity over five different courses (length 120-200 m) with mean slopes of -1, 0, 6, 9, and 12%. Video analysis was used to determine skiing velocity, cycle length, and cycle rate. Heart rate was monitored to verify intensity of exertion. Results indicated that intensities were similar to those observed while racing. Velocities for the three techniques were not different for -1, 0, and 6% slopes. However V-1 was significantly faster (P0.01) at 9% and 12% inclines. Velocity was highly correlated to cycle length (P0.01) but unrelated to cycle rate. Cycle length was significantly different between techniques (P0.01) and varied across slopes. Cycle rate was significantly different between techniques (P0.01) but did not vary across slopes. Thus, our results indicate that any of the three techniques is adequate on flat and rolling terrain, but V-1 should be used at slopes of 9% and above. It is also concluded that during short trials skied at maximal velocity, skiing velocity is highly dependent on cycle length and independent of cycle rate.

Introduction Supernovae are important for the study of several astrophysical problems – nuclear processing in stellar interiors, distance scale determinations, and the chemical enrichment of the interstellar medium have all been explored. Additionally, they may be used as background probes of interstellar gas by studying, for example, NaI and CaII lines, sampling the gas in the host galaxy, the Milky Way halo gas, and any intervening intergalactic gas. SN 1987A allowed the detailed study of gas towards and within the LMC to a distance D ≃ 0.05 Mpc (Vidal-Madjar et al. 1987, de Boer et al. 1987). With the unusually bright SN 1993J in M81 it is now possible to extend the search for interstellar/intergalactic absorptions beyond the local group of galaxies, out to the distance of the M81 group at a distance of D~3.25 Mpc. In this paper we present a preliminary study of high resolution optical interstellar spectra towards SN 1993J. The observations are described in section 2. The origin of the absorption lines, which fall into three distinct groups are discussed in section 3. Observations The observations of SN 1993J were obtained during the nights 1993 April 4–8, using the Utrecht Echelle Spectrograph on the William Herschel Telescope at the Observatorio del Roque de los Muchachos, La Palma.

Cardiac papillary fibroelastomas are unusual, frond-like growths typically found on cardiac valves, diagnosed incidentally on autopsy or cardiac surgery, but rarely during life. We report a rare case of an aortic valve papillary fibroelastoma detected by transthoracic echocardiography and confirmed by histologic study.

Teething as a disease entity has been diminished from its 19th century status as the major cause of infant mortality to its modest position today as a "waste basket" diagnosis. If past proves to be prologue, it will diminish further as more credible causes for undifferentiated fevers and other complaints are found. The 21st century may find teething consigned to the shelf along with miasma, humoral theory, mesmerism, and other archival curiosities.

Congenital anomalies of the coronary arteries are relatively uncommon conditions with an incidence of approximately 2% in the adult population. Although less common than acquired coronary artery disease, these anomalies may be associated with myocardial ischemia and its consequences; angina, arrhythmia, infarction, and sudden death. A 21-year-old female patient with no significant prior medical history was found dead at home. Postmortem examination revealed high take-off of the right coronary artery with acute down-ward angulation of the proximal right coronary artery and acute downward angulation of the left main coronary artery. Microscopic examination revealed global myocardial ischemia consistent with a terminal ventricular dysrhythmia. There was no evidence of any other disease processes. Detailed toxicological investigation was negative. The Regional Forensic Pathology Unit experience with sudden death due to congenital coronary artery anomalies is presented along with a review of the current literature.

Lack of spatial registration of imaging transducers is a major technical limitation of two-dimensional (2-D) echocardiography. Volume scanning of the heart, or three-dimensional (3-D) echocardiography, is achieved by using a 3-D spatial registration device with a conventional 2-D scanner, or by using a high speed, phased-array real-time scanner. Three-dimensional spatial coordinate systems may be external or internal systems with respect to the scanning transducer. With external systems data acquired from several cardiac windows may be integrated and reconstructed. An external coordinate system allows creation of a "line of intersection" display to guide image positioning in the nonvisualized dimension orthogonal to the real-time image. Use of this display has shown a significant, threefold improvement in the accuracy of image positioning and the reproducibility of chamber measurements. Three-dimensional echocardiography using polyhedral surface reconstruction also yields more accurate measurement of ventricular volume and new measurements of total endocardial surface area and infarct surface area. Computer modeling and 3-D computergraphic displays hold promise of valuable new methods of communication, data analysis, and surgical planning.

The authors consider mandibular infiltration as a possible alternative to mandibular block anesthesia in young children. The study sample comprised eighteen children ages six to nine years old who required bilateral identical treatment on primary mandibular molars. A random number table was used to determine which side of the mouth was to receive the block or the infiltration technique and a coin toss determined which would be administered first: A short 27 gauge needle was used to inject a 2 percent lidocaine solution with 1:100,000 epinephrine, in both techniques. The paired t-test indicated no significant difference between the two techniques for any of the factors evaluated.

The Drosophila chorion factor 1/ultraspiracle (CF1/USP) transcription factor, a homologue of the retinoid X receptor, is a developmentally important member of the family of nuclear (steroid) hormone receptors. Using newly developed monoclonal antibodies and a full-length bacterially produced protein, we have studied in detail the in vitro DNA-binding properties of this factor and aspects of its distribution in vivo. During oogenesis, CF1/USP is present both in germline cells and in the somatic follicular epithelium. We have determined the optimal binding site of partially purified bacterially produced CF1/USP by an in vitro selection procedure and also have characterized its binding to the follicular-specific chorion s15 promoter. In vitro this bacterially produced factor is unusual in binding to a single element ("half-site"); simultaneous but noncoordinate binding to a second half-site is possible if these repeated elements are organized in direct orientation and spaced adequately. However, the factor interacts synergistically with several other nuclear hormone receptors: notably, it can form in vitro heteromers with mammalian thyroid and retinoic acid receptors, binding to two half-sites that are organized in either direct or inverted orientation. In vivo the factor most probably functions as a heterodimer, but its partner(s) remains to be determined.

This investigation was conducted to determine whether primary herpetic gingivostomatitis may be responsible for those signs and symptoms commonly attributed to teething in infants. Twenty infants presenting with a parental diagnosis which indicated teething difficulty were included in this study (Group A). Twenty infants who were in no distress served as controls (Group B). Oral swab samples were obtained from each infant and then processed to ascertain the presence of herpes simplex virus (HSV). Each infant's temperature and oral status also were recorded. Nine subjects in Group A (45%) were positive for HSV. Of these nine, seven had elevated temperatures (less than 100 degrees F) and all had signs of oral infection of varying severity. Of the 11 subjects in Group A who were negative for HSV, five had elevated temperatures, but none showed evidence of oral infection. Subjects in Group B were all negative for HSV, elevated temperature, and signs of oral infection. Results of this study suggest that oral HSV infection should be included in the differential diagnosis of infants presenting with a parental diagnosis of teething difficulty.

We have constructed a three-dimensional (3-D) ultrasound scanner to make examinations easier and more accurate. The accuracy of the 3-D scanner has been determined by scanning a three-dimensional model. Lengths, angles, and volume of the model were computed and compared to values determined from physical measurement. Distances between image planes were computed with a mean error of 0.4% of true value. Volume was computed with a mean error of 1.6%, or 0.64 mL +/- 0.72 mL (1 SD). We conclude that the 3-D scanner has a system error of less than 0.4%, that it does not introduce significant new errors, and that the principal source of measurement error is poor lateral resolution due to ultrasound beam width. We believe that the 3-D scanner may be a clinically useful instrument for quantitative echographic measurements.

Gel mobility-shift assays have been used to identify proteins that bind specifically to the promoter region of the Drosophila s15 chorion gene. These proteins are present in nuclear extracts of ovarian follicles, the tissue where s15 is expressed during development, and bind to specific elements of the promoter that have been shown by transformation analysis to be important for in vivo expression. The DNA binding specificity has been used for molecular cloning of two components from expression cDNA libraries and for their tentative identification with specific DNA-binding proteins of the nuclear extracts. The mRNAs for both of these components, CF1 and CF2, are differentially enriched in the follicles. DNA sequence analysis suggests that both CF1 and CF2 are novel Drosophila transcription factors. CF2 is a member of the C2H2 family of zinc finger proteins, whereas CF1 is a member of the family of steroid hormone receptors. The putative DNA-binding domain of CF1 is highly similar to the corresponding domains of certain vertebrate hormone receptors and recognizes a region of DNA with similar, hyphenated palindromic sequences. The nature of CF1 raises the possibility of hormonal control of choriogenesis in Drosophila.

Distance, similarity, and other components of the physical stimulus but also gestalts are associated with the ability to discriminate between two objects. The present research bears on this confound. Identical lines were added to the opening and closing bracket of a pair of brackets to form two identical rectangles. A stimulus consisted of either one or two of these brackets, lines, or rectangles. Subjects indicated as quickly as possible whether one or two objects occurred. The discriminations between two near brackets and two near lines were more difficult than the discrimination between two near rectangles. A large distance between two objects improved the bracket and line discriminations more than the rectangle discrimination. Single brackets and lines did not result in poorer performance than did single rectangles. These results disconfirm the distance, similarity (including relational similarity), good continuation, location of geometric centers, size, closedness, symmetry, spatial frequency, redundancy, and number of lines component stimulus predictions at least twice. Both the two near brackets and the two near lines produce single gestalts, whereas each remaining 2-object stimulus results in two gestalts. Therefore, gestalts predicted performance better than did component stimuli. Another result was that the 2-object responses were faster than the 1-object responses for far objects.

Congenital anomalies of the coronary arteries are relatively uncommon conditions with an incidence of approximately 2% in the adult population. Although less common than acquired coronary artery disease, these anomalies may be associated with myocardial ischemia and its consequences; angina, arrhythmia, infarction, and sudden death. A 21-year-old female patient with no significant prior medical history was found dead at home. Postmortem examination revealed high take-off of the right coronary artery with acute down-ward angulation of the proximal right coronary artery and acute downward angulation of the left main coronary artery. Microscopic examination revealed global myocardial ischemia consistent with a terminal ventricular dysrhythmia. There was no evidence of any other disease processes. Detailed toxicological investigation was negative. The Regional Forensic Pathology Unit experience with sudden death due to congenital coronary artery anomalies is presented along with a review of the current literature.

Continuously increasing oil prices, a dwindling supply of indigenous petroleum, and the existence of extensive coal reserves has made the conversion of coal to chemicals and clean-burning fuels an increasingly important part of the national energy programs for a number of industrial nations. In particular, there is a growing interest in the production and use of synthesis gas as a feedstock for the manufacture of fuels and chemicals. Most of the proposed routes are catalytic in nature, and are directed at overcoming the limitations of Fischer-Tropsch chemistry, especially selectivity. Over the past several years, research efforts have led to new selective routes to various fuel fractions; to petrochemical feedstocks including light olefins and various aromatics; to commodity chemicals such as ethylene glycol, ethanol, and acetic acid; and to a number of other fuels and chemicals.

Observations photographiques d'etoiles variables de V plus lumineux que 18 dans une region de 21,4 degres carres au-dessus de la calotte galactique sud. On a obtenu les periodes et courbes de lumiere de 6 variables RR Lyrae

In connection with measurements already reported on the enthalpy of solution of HBr(g) (76), we needed values for the enthalpy of dilution of HBr(aq) which were more reliable than those then available in the literature (73). The tabulated values were based on direct dilution measurements by Thomsen ( 7 4 ) and Berthelot ( 7 ) at 19" and 15.5OC and on indirect measures of partial molar enthalpies from emf sources (8). The measurements reported in this paper were begun immediately after completion of our measurements on the enthalpy of solution of HBr(g) (76), and most were completed at the time Parker's revision (72) of previously tabulated (73) relative apparent molar enthalpies, $L, appeared in print. Subsequent measurements involved a closer examination of the region between 8 and 12m to determine whether any anomalous trend in @L existed at the azeotrope composition. The results reported here reveal no anomaly. Measurements were extended to 22.35m, and the relative partial molar enthalpy L2 was evaluated over the whole range of molalities studied.

In this rapid TLC method of analysis for the urinary cannabinoid metabolite, 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), hydrolyzed urine specimens are aspirated through a porous, alkyl-silica extraction layer located along the lower edge of a biphasic thin-layer chromatogram; THC-COOH is simultaneously extracted from the sample and concentrated on the TLC plate for subsequent migration and detection. The method, evaluated in a blind study, identified all samples containing THC-COOH greater than or equal to 20 micrograms/L. The technique increases samples throughput, sensitivity, and specificity as compared with conventional TLC methods and is applicable to a wide variety of compounds.

The number of methods available for laboratory detection of cannabinoids is constantly increasing. This article reviews the chemistry and metabolism of marijuana, recent developments in analytic methods, and current therapeutic applications of cannabinoids.

(1966). Radiotherapy in the Management of Meningiomas. Acta Radiologica: Diagnosis: Vol. 5, No. 1, pp. 26-33.