Search

The rate of increase in database size and response-time requirements has outpaced advancements in processor and mass storage technology. One way to satisfy the increasing demand for processing power and input/output bandwidth in database applications is to have a number of processors, loosely or tightly coupled, serving database requests concurrently. Technologies developed during the last decade have made commercial parallel database systems a reality, and these systems have made an inroad into the stronghold of traditionally mainframe-based large database applications. This paper describes the DB2® Parallel Edition product that evolved from a prototype developed at IBM Research in Hawthorne, New York, and now is being jointly developed with the IBM Toronto laboratory.

The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara.

Individuals deficient in hepatic methionine adenosyltransferase (MAT) activity (MAT I/III deficiency) have been demonstrated to contain mutations in the gene (MATA1) that encodes the major hepatic forms, MAT I and III. MAT I/III deficiency is characterized by isolated persistent hypermethioninemia and, in some cases, unusual breath odor. Most individuals with isolated hypermethioninemia have been free of major clinical difficulties. Therefore a definitive diagnosis of MAT I/III deficiency, which requires hepatic biopsy, is not routinely made. However, two individuals with isolated hypermethioninemia have developed abnormal neurological problems, including brain demyelination, suggesting that MAT I/III deficiency can be deleterious. In the present study we have examined the MATA1 gene of eight hypermethioninemic individuals, including the two with demyelination of the brain. Mutations that abolish or reduce the MAT activity were detected in the MATA1 gene of all eight individuals. Both patients with demyelination are homozygous for mutations that alter the reading frame of the encoded protein such that the predicted MATalpha1 subunits are truncated and enzymatically inactive. The product of MAT, S-adenosylmethionine (AdoMet), is the major methyl donor for a large number of biologically important compounds including the two major myelin phospholipids, phosphatidylcholine and sphingomyelin. Both are synthesized primarily in the liver. Our findings demonstrate that isolated persistent hypermethioninemia is a marker of MAT I/III deficiency, and that complete lack of MAT I/III activity can lead to neurological abnormalities. Therefore, a DNA-based diagnosis should be performed for individuals with isolated hypermethioninemia to assess if therapy aimed at the prevention of neurological manifestations is warranted.

A newborn infant born to consanguineous (first cousin) parents was noted to have complex congenital heart defect and minor anomalies suggestive of trisomy 18. Blood lymphocyte and skin fibroblast karyotypes were normal. He died in the neonatal period of postoperative complications. On interphase fluorescence in-situ hybridization (FISH) using autopsy specimens, a significant number of cells in the liver (17%) were trisomic for chromosome 18, compared to normal control liver tissue. However, interphase FISH analyses of blood lymphocytes, skin fibroblasts, and kidney tissue were normal. It is our opinion that this apparent mosaicism for trisomy 18 in the patient's liver may be spurious, though it brings into focus the issue of possible tissue/organ-specific mosaicism. The anomalies in this infant do not resemble a previously described malformation syndrome. Parental consanguinity raises the possibility that this represents a new autosomal recessive malformation syndrome.

Two patients and one three generation family with interstitial deletions of distal chromosome band 14q31 are described. The deletions were initially identified by chromosome analysis; we have used highly informative simple sequence repeat polymorphisms to define the deletions at the molecular level. This analysis also establishes the parental origin of the deleted chromosome. One of the patients was initially described as having a terminal deletion of chromosome 14 from 14q31 to 14qter; we show here that this child has instead an interstitial deletion of band 14q31. The smallest deletion involves a single anonymous DNA marker and is associated with an almost normal phenotype. The two patients with larger deletions have phenotypes similar to those seen in previously described cases of interstitial deletions of chromosome 14, including minor dysmorphic features and developmental delay. Delineation of these deletions allows the ordering of markers within the 14q31 region, in which the gene for the degenerative neurological disorder Machado-Joseph disease is localised.

The recent advances in infrared technology have led to large two-dimensional detector arrays in a range of materials including cadmium mercury telluride, platinum silicide, and ceramic pyroelectric materials. The relatively high temperature sensitivity of these arrays compared with scanned detectors is being exploited in advanced electro-optic equipment either directly or by trading off against other parameters. A major difficulty which faces system designers is that of system performance prediction prior to expensive build and trial phases. In the past, this has been overcome using a number of established computer models which were developed for conventional scanned imagers. However, the principle of operation of staring imagers is so different that a new approach is required. This paper describes a modular computer simulation of staring array imagers.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In three infants with neonatal lacticacidaemia, a deficiency in the E1 (pyruvate dehydrogenase) component of the pyruvate dehydrogenase complex was demonstrated in skin fibroblast cultures. Residual activities of the pyruvate dehydrogenase complex in the activated state were 1.6%, 3.9% and 18.8% of control values, respectively. Immunoprecipitation of extracts of cultures skin fibroblasts grown on 35S-methionine with anti-pyruvate dehydrogenase complex antibody revealed an abnormality in the E1 alpha-component of these three patients when visualised after sodium dodecyl sulphate/polyacrylamide gel electrophoresis. This component appeared to have a slightly lower molecular weight than did this protein from control cell strains. Cell strains from other patients with a deficiency of the pyruvate dehydrogenase complex did not exhibit this defect. Three patients also showed dysmorphism and developmental abnormalities of the central nervous system.

An effusive molecular beam of aniline vapor has been two‐step ionized by irradiating it with the output from a frequency doubled dye laser. Photoelectrons ejected while exciting several different vibronic levels of its 1B2 electronic state have been kinetic energy analyzed. In all cases ions are found to be generated in their ground electronic state. Their vibrational state distribution is strongly wavelength dependent and differs remarkably from that obtained in conventional single photon photoelectron spectroscopy. The energies of several in‐plane vibrational modes of aniline cations have been measured. In contrast with the ground electronic state of the neutral molecule, the ground state of the ion and 1B2 excited electronic state of the neutral molecule both appear to be nearly planar.

What are the conditions necessary for the formation of rare earth oxides? Why is there an enrichment of lanthanum in oxysulfide type inclusions? Why is there an apparent sequence of formation of the various types of rare earth inclusions in steel?

Electric fields in the ionosphere may be measured by using probe techniques. Previous authors have indicated that the accuracy of the measurement may be improved by allowing the system to operate at probe currents other than zero, the latter being the normal floating potential mode. The design of an experiment which achieves measurements of electric fields at different probe currents is described. Particular attention is paid to the current generators and differential amplifiers which are the critical sections. The accuracy of the experiment is discussed and an initial flight result is presented.

This paper discusses the problems and benefits of using the Prolog language to write application programs. Much attention is currently focused on expert-systems shells, which play a role in artificial intelligenc(AI) systems similar to that of application generators in more conventional applications. The Prolog programming language embodies many of the features found in these shells, while providing a relatively general and complete programming language. MVS performance tuning is used as an application that typifies a broad class of applications suitable for implementation in this language. Some of the difficulties that had to be overcome to use the language are presented, with their solutions.

The authors measured positron total scattering cross sections for Ne, Ar, Kr and Xe between 1 and 6 eV employing a time-of-flight spectrometer which has a straight beam-line geometry. A comparison with other results shows rather good agreement for neon but serious deviations for the other gases; the authors' cross section values lie distinctly above the others.

The relative electron detection efficiency of a detector consisting of two microchannel plates (MCP) in a chevron arrangement with a carbon coated high transmission (94%) copper grid 6 mm in front of the first MCP was experimentally determined. The energy of the electrons hitting the detector was varied by accelerating a pulsed electron beam of known energy. By modeling the secondary electron emission from the grid and averaging for possible variations in the electron flux, the relative efficiency was determined to within 2% in the range ∼0 to 3 keV. Fits of the relative efficiency to an analytic expression as a function of incident energy and grid bias energy are reported.

The Proteus syndrome (PS) and the Bannayan-Zonana syndrome (BZS) both have multiple hamartomata as prominent features. Hemihypertrophy, macrodactyly, exostoses, skin lesions, scoliosis, and sporadic occurrence are seen in PS, whereas patients with BZS have macrocephaly and related craniofacial findings. BZS has been observed in families as an autosomal dominant trait. Although the two syndromes can be distinguished in most patients, there are features in common to both that may pose a diagnostic dilemma in an isolated case. We report the case of a 3-year-old girl with macrocephaly, macrodactyly, and superficial and intra-abdominal hamartomata who illustrates the problem of differentiating between PS and BZS. We compare this patient and another recently reported patient with other published cases of PS and BZS. Patients with PS, in general, show more extensive systemic involvement, including skeletal and cutaneous manifestations. Macrocephaly, seen in all reported patients with BZS, is also found in 14% of patients with PS. Overlap among syndromes which include hamartomata as prominent features suggests that they might be etiologically or pathogenetically related. The present case also illustrates the usefulness of imaging techniques in the diagnosis of mixed mesodermal hamartomata.

The absolute total electron scattering cross section for He(21S0) and the relative total electron scattering cross section for He(23S1) have been measured in the electron energy range 0.45-9.4 eV. The results show a structureless decrease of the cross sections with increasing electron energy. Comparisons of the results with theory and with the experimental results of Neynaber et al. (1964) for the triplet scattering cross section are given.

New experimental results on the total cross section for low-energy positron scattering from helium are presented and compared with other experimental data as well as theoretical predictions.

We have selected four widely different flares from the early period of operations of the Hard X-Ray Imaging Spectrometer (HXIS) on SMM to illustrate the characteristic imaging properties of this experiment. For the small flare of April 4, 1980, we demonstrate the instrument's capability for locating a compact source. In the weak, but extensive, flare of April 6 we show how well the instrument can display spatial structure, and also the low level of the instrument background. In the 1B flare of April 7 we are able to locate positions of the X-ray emission in the soft and hard channels, and estimate the positional variations of the emission patches. Finally, in the IN flare of April 10, which produced the strongest hard X-ray burst we have seen so far, we repeat some of the studies made for the April 7 event, and also demonstrate the capability of the HXIS instrument to study the development, with high time resolution, of individual 8″ × 8″ elements of the flare.

Introduction The present paper is offered as a contribution to the already voluminous literature on the origin of the basins of the Great lakes in the belief that the matter here presented not only is of great importance in the attempt to find a correct solution of the problem, but also because, so far as the writer’s study of the literature has gone, the facts here set forth have been largely overlooked in the earlier studies of this question. In a paper published three years ago the writer very briefly outlined some of the facts and conclusions given here in more detail.[*][1] The important bearing which the studies then made appeared to have on the origin of the Saint Lawrence outlet from lake Ontario led him to delay fuller publication until he had been able to continue and extend the field work begun at that time. During the past two . . . [1]: #fn-1

The performance of the BK24 ignitron as a switch in high current pulsed applications is studied, the closed circuit impedance of the valve for fast (loss than 100 μsec) and slow (msec), pulses being investigated. The valve resistance is found to fall from an initial valve of 23 m Ω to a minimum of a few milliohms some hundred microseconds after ignition. The rating of the valve for fast pulse operation is discussed.

The instruments which measure electron density and temperature are quite separate and independent in operation, but on account of the limitations in power supply and telemetry data rate the two experiments share the same power lines and some data channels.

Flow disturbances in supersonic rocket nozzles due to secondary injection analyzed by effective body approximation, including side forces

A simple feedback integrator of bandwidth from 2 c/s to 20 kc/s is analysed theoretically to show how the circuit may be modified to produce an integrator of bandwidth from 5 c/s to 2 Mc/s with less than 10% error at the band edges. The design and performance of the modified integrator is described in detail.

n/a

General Character of the Basins of both Lakes TOPOGRAPHY OF THE BASINS—COMPLEX The general character of the topography of the basins of the different lakes can be most readily understood from the standpoint of a physiographer by describing the region as an ancient belted coastal plain subsequently modified by glacial ice. The inner lowland, that bounded on the south and southwest by the Niagara cuesta, is occupied in part by the Georgian bay and in part by the bed of lake Ontario, there being also in Ontario an unsubmerged portion of this lowland lying between the two bodies of water just mentioned. The outer lowland, bounded by the margin of the Cumberland plateau, is in its lowest parts occupied (in part) by the beds of lakes Erie, Huron, and Michigan. The waters of Georgian bay, which is confluent with lake Huron, cover parts of the inner and innermost lowlands, and . . .

A patient with the Brachmann-de Lange syndrome was found to have an apparently balanced de novo translocation 14q; 21q. The relationship between this uncommon translocation and the patient's phenotype is unclear. Although most patients with the Brachmann-de Lange syndrome have normal chromosomes, the possibility of aetiological heterogeneity, including some rare chromosomal abnormalities, cannot be dismissed.

Two brothers with developmental delay and unusual cranial configurations were found to have agenesis of the corpus callosum (ACC) by CT scan. Six published families in which ACC occurred in the absence of extracranial malformations are reviewed. No single mode of inheritance can account for all of these familial cases. This family illustrates the value of CT scanning in evaluating children with developmental delay.

A five-year-old-girl with a history of recurrent hypoglycemia presented with acidosis, intractable vomiting, and abdominal tenderness; the diagnosis of acute pancreatitis was made by abdominal ultrasonography and supportive biochemical studies. Urinary organic acid analysis revealed metabolites suggestive of HMG-CoA lyase deficiency, and subsequent enzyme assays of lymphocytes and fibroblasts confirmed this diagnosis. Acute pancreatitis, an uncommon condition in childhood, is seen with increased frequency in patients with Reye syndrome, a metabolic disorder with which HMG-CoA lyase deficiency may be confused. The pathogenesis of pancreatitis in Reye syndrome or in HMG-CoA lyase deficiency has not been determined.

The intracellular levels of substates and products of G6PD were measured in normal human red cells that were incubated in a Krebs-Ringer buffer without methylene blue and with increasing amounts of methylene blue. The use of [1-14C]glucose and [2-14C]glucose allowed estimates of the rate at which the G6PD was functioning within the cell. Kinetic characteristics of the purified enzyme were determined in the same Krebs-Ringer buffer. G6PD of normal red cells exhibits two unusual properties. (1) The intracellular enzyme is under unexplained intracellular restraint that ranges from 200-fold (if most of the NADP is in the reduced form) to five-fold (if most of the NADP is in the oxidized form). When coupled with earlier reports, these findings suggest that unexplained intracellular restraint is common to both G6PD-normal and G6PD-deficient (A-) red cells, (2) A highly sigmoid curve is obtained when the rate of the intracellular enzyme is plotted against the ratio of oxidized NADP to total NADP. In contrast, a nearly straight line is obtained with the corresponding plot of the pure enzyme under similar conditions of buffer and substrate concentration.

The first rotationally resolved photoelectron spectrum of molecule other than H/sub 2/ is reported. NO is ionized from selected quantum levels of its A(/sup 2/..sigma../sup +/) excited electronic state. One strong peak and two weak peaks, corresponding to ..delta..N = 0 and ..delta..N = +/-2 rotational transitions, respectively, are observed. This rotational selection rule is the same as that observed when hydrogen is ionized from its chi/sup 1/..sigma../sub g//sup +/ ground electronic state but differs from that observed when it is ionized from its B/sup 1/..sigma../sub u//sup +/ state.

We reviewed the results of lymphocyte karyotypes from 232 couples who had had two or more pregnancy losses (spontaneous abortions or stillbirths). Despite the use of strict criteria to correct for possible bias of ascertainment, 8% of these couples (19 of 232) had a chromosome abnormality. Six of these abnormalities were low-percentage mosaicism for aneuploidy or a translocation. If these couples were excluded, 13 (6%) of the study couples had a chromosome abnormality. There was no significant difference in the incidence of chromosome abnormalities in those couples having two losses as compared with those having three or more losses. The study couples were referred from a wide range of sources, and most women had not had extensive gynecologic evaluation. These results confirm the importance of cytogenetic analysis of couples with recurrent pregnancy loss, and suggest that such studies be considered after two losses.

A family is described in which four persons in three generations suffered spontaneous pneumothoraces: a newborn, an infant, an adolescent, and an adult. Review of the literature reveals 61 reports of familial spontaneous pneumothorax in 22 families. The ratio of male to female cases is approximately 1.8. Affected parents and affected children (including affected fathers and sons) are seen in ten families, while affected siblings with unaffected parents are noted in 13 families. Consanguinity has not been reported. Although autosomal dominant inheritance has been suggested as an explanation of familial spontaneous pneumothorax, available pedigree data are not adequate for statistical analysis. Physicians should be aware of the familial occurrence of spontaneous pneumothorax so that members of such families may be appropriately managed when problems arise.

We describe a fetus with hydrocephalus and the cranial and cervical findings of iniencephaly (enlarged foramen magnum, fusion of the upper cervical vertebrae, and a retroflexed, webbed neck) who had an unusual palatal abnormality ("palatal anteversion"). The posterio-lateral border of the secondary palate arose at the oral commissures, giving the palate an appearance of being folded so that the uvula was directed anteriorly. There were no clefts. Histologic sections of the junction of the secondary palate with the inner aspect of the oral commissures revealed continuity of the epithelial basement membranes and no unusual disarray of collagen fibers. This indicates that the unusual palatal orientation occurred during palatal formation and was not due to adhesion formation later in development. Failure of rotation of the palatal shelves prior to fusion and merging could account for the observed findings.

A patient with multiple exostoses, mental retardation, and unusual facies has an interstitial deletion of the long arm of chromosome 8, or 46,XX, del (8) (pter leads to q22::q24.1 leads to qter). She has some features of the Langer-Giedion syndrome, but her facies are not characteristic and she does not have cone-shaped phalangeal epiphyses. Of the eight previous reports of partial deletion of the long arm of chromosome 8, four patients had exostoses and unusual facies, three of whom had characteristics of the Langer-Gieldion syndrome. The deleted segments in the patients with exostoses are not identical, although there are areas of deletion that are seen in more than one patient. Among the explanations of the relationship of the 8q deletions to exostoses is the presence of several loci on 8q that are involved in bone formation, the deletion of any of which may give rise to a similar skeletal defect.

We report a 2-year-old male infant with the Coffin-Lowry syndrome, and describe the change in his clinical and radiographic manifestations during the first 2 years of life. Review of published cases of the Coffin-Lowry syndrome indicates that these manifestations are progressive, and that all of the associated characteristics may not be apparent in early childhood. The importance of continued evaluations of these patients and examination of relatives for mild manifestations is emphasized.