cssi/SciSciGPT-SciSciNet huggingface dataset:
An investigation of the high-temperature and solidification microstructures of PH 13-8 Mo stainless steel

Differential thermal analysis (DTA), high-temperature water-quench (WQ) experiments, and optical and electron microscopy were used to establish the near-solidus and solidification microstructures in PH 13-8 Mo. On heating at a rate of 0. 33 °C/s, this alloy begins to transform from austenite to δ-ferrite at ≈1350 °C. Transformation is complete by ≈1435 °C. The solidus is reached at ≈1447 °C, and the liquidus is ≈1493 °C. On cooling from the liquid state at a rate of 0. 33 °C/s, solidification is completed as δ-ferrite with subsequent transformation to austenite beginning in the solid state at ≈1364 °C. Insufficient time at temperature is available for complete transformation and the resulting room-temperature microstructure consists of matrix martensite (derived from the shear decomposition of the austenite) and residual δ-ferrite. The residual δ-ferrite in the DTA sample is enriched in Cr (≈16 wt pct), Mo (≈4 wt pct), and Al (≈1. 5 wt pct) and depleted in Ni (≈4 wt pct) relative to the martensite (≈12. 5 wt pct Cr, ≈2 wt pct Mo, ≈1 wt pct Al, ≈9 wt pct Ni). Solid-state transformation of δσ γ was found to be quench-rate sensitive with large grain, fully ferritic microstructures undergoing a massive transformation as a result of water quenching, while a diffusionally controlled Widmanstatten structure was produced in air-cooled samples.
Information systems: a key ingredient to achieving organizational competitive strategy

Abstract The development and use of information systems as instruments of organizational competitive strategy are becoming key factors in today's business environment. Industries have recognized the fact that information systems will increase their organizations' competitiveness and overall profitability. However, a number of organizations have also recognized that before information systems can be developed and used effectively, there must first be a throrough understanding of the business opportunities available. Once these organizations have clearly recognized and defined these opportunities, they must then implement the tools and methodologies to help develop an information system which will assist them in enhancing their competitive strategy.
Effects of changes in cortical arousal and of auditory cortex cooling on neuronal activity in the medial geniculate body.

The activity of cells in the medial geniculate body (MGB) of adult cats was recorded during different states of cortical arousal with and without cooling of the auditory cortex. In the absence of auditory cortex cooling, the overall mean unit spontaneous discharge rate was 49% higher during desynchroized Electrocorticogram (ECoG) periods (high cortical arousal). Responses to sound were somewhat more prominent vis-a-vis the spontaneous activity during periods of high arousal. Changes in spontaneous discharge rate associated with arousal shifts were significantly reduced during auditory cortex cooling. When the ECoG changed from desynchronized to synchronized activity, MGB cells showed a change in discharge pattern, typically characterized by an increase in both high-rate bursts and long-interval pauses. These changes were duplicated for most cells by cooling of the auditory cortex. Corticofugal fiber discharge thus has an effect on MGB neuronal activity which is dependent on the level of cortical arousal. This effect is most likely a result of direct corticogeniculate activity, though indirect auditory cortex - brainstem - MGB routes may also be involved.
A plaque assay for titration of alfalfa looper nuclear polyhedrosis virus in a cabbage looper (TN-368) cell line

Abstract This is the first report of plaque formation by a pathogenic insect virus. Trichoplusia ni (TN-368) cells overlaid with medium containing 0.6% methyl cellulose continued to multiply, developed into monolayers, and produced plaques after infection with alfalfa looper nuclear polyhedrosis virus. Viral polyhedral inclusion bodies were first observed 24 hr after exposure of cells to virus, and plaques continued to increase in size for 72 hr. Two different types of plaques were observed: one in which all cells had many polyhedra in their nuclei, and another in which few cells had inclusion bodies. When virus from either plaque was injected into T. ni larvae, they died of typical nuclear polyhedrosis virus disease. The assay was reproducible, and plaque numbers were related to virus concentration.
Correlation between decreased collagen production in diabetic animals and in cells exposed to diabetic serum: response to insulin.

Collagen production has been shown to be decreased in costal cartilage from nondiabetic animals after incubation with diabetic rat serum. Since collagen was decreased to a similar degree in tissues from diabetic animals, we questioned whether altered collagen production in vivo could be related to altered production induced in vitro. Collagen and noncollagen protein production in articular cartilage from diabetic animals (production in vivo) was compared to protein production in dermal fibroblasts from non-diabetic rats exposed to serum from the same diabetic rats (production in vitro). Diabetes was induced by intravenous administration of 90 mg/kg of streptozotocin into male Sprague-Dawley rats. Cartilage was removed and incubated with [3H]-proline for 2 hours at 3°C (in vivo), while fibroblasts were exposed to experimental serum from individual animals for 24 hours with addition of 5 µCi of [5-3H]-proline for the final 6 hours (in vitro). Collagen and noncollagen protein production were quantitated using purified bacterial collagenase. Collagen production in cartilage decreased to 46% (p<.01) and noncollagen to 68% (p<.05) of levels in control animals. Fibroblasts exposed to 2.5% diabetic serum decreased collagen and noncollagen protein production to levels of 30% (p<.01) and 54% (p<.05) of production in cells incubated in 2.5% normal rat serum. Correlation between defective collagen production in cartilage from individual rats and the effects of their own serum on collagen production in fibroblasts was significant (r = 0.84, p<0.001). Insulin treatment of diabetic animals returned collagen production to control levels in cartilage and fibroblasts exposed to serum in vitro. Addition of insulin directly to diabetic serum did not return collagen production to levels seen in cells exposed to normal rat serum. These results demonstrate that the effect of insulin on normalizing collagen production was mediated via correction of a circulating factor(s) in diabetes rather than direct effects of insulin on protein production, and suggest a circulating mediator of altered collagen production.
Landscape change and its effects on the wintering range of a lesser snow goose Chen caerulescens caerulescens population: A review

The Texas coast has experienced considerable urban, industrial, and agricultural growth during the 20th Century. The region provides important wintering habitat to many avian species, including lesser snow geese Chen caerulescens caerulescens. This paper draws the biological and ecological fields into an historical perspective by examining available literature on the development of the upper Texas coast and range changes of lesser snow geese. Historically, lesser snow geese wintered in the coastal marshes, but expanded their range into the adjacent prairies in the mid-1900s. Winter range expansion was negatively affected by urban and industrial encroachment in the coastal marshes and positively influenced by agricultural development in the prairies, which increased dramatically during World War II. The lesser snow goose population flourished alongside some human-induced landscape alterations. However, projected declines in agriculture and increased urbanization of prairie and coastal marsh habitats may result in significant negative effects on the lesser snow goose population.
Brain and Spinal Cord Interaction: A Dietary Curcumin Derivative Counteracts Locomotor and Cognitive Deficits After Brain Trauma

Background. In addition to cognitive dysfunction, locomotor deficits are prevalent in traumatic brain injured (TBI) patients; however, it is unclear how a concussive injury can affect spinal cord centers. Moreover, there are no current efficient treatments that can counteract the broad pathology associated with TBI. Objective. The authors have investigated potential molecular basis for the disruptive effects of TBI on spinal cord and hippocampus and the neuroprotection of a curcumin derivative to reduce the effects of experimental TBI. Methods. The authors performed fluid percussion injury (FPI) and then rats were exposed to dietary supplementation of the curcumin derivative (CNB-001; 500 ppm). The curry spice curcumin has protective capacity in animal models of neurodegenerative diseases, and the curcumin derivative has enhanced brain absorption and biological activity. Results. The results show that FPI in rats, in addition to reducing learning ability, reduced locomotor performance. Behavioral deficits...
IDENTIFICATION OF OPTIMAL REDUCED ORDER HOMOGENIZATION MODELS FOR FAILURE OF HETEROGENEOUS MATERIALS

This manuscript presents a new methodology for the identification of optimal reduced order models for the inelastic and failure response of heterogeneous materials. The proposed methodology employs the eigendeformation-based reduced order homogenization approach. The identification of the optimal reduced order model is posed as an integer optimization problem and the genetic algorithm method is used to evaluate the optimization problem. A second optimization problem is posed to ensure that the errors associated with the optimal reduced order model are minimized through scaling of the failure parameters. The performance and capabilities of the optimal reduced order models identified based on the proposed approach are demonstrated by comparing model predictions with the computational homogenization method with full resolution of the material microstructure. Numerical simulations conducted using unidirectional reinforced matrix microstructures reveal that the reduced order models accurately describe the response characteristics of the composite material for a wide range of loading regimes.
Superparamagnetism and relaxation effects in granular Ni-Si O 2 and Ni- Al 2 O 3 films

The susceptibility of an array of fine nickel particles was measured as a function of temperature from 1.5 to 300 \ifmmode^\circ\else\textdegree\fi{}K at a frequency of 5 kHz. The particles were formed by cosputtering nickel with Si${\mathrm{O}}_{2}$ or ${\mathrm{Al}}_{2}$${\mathrm{O}}_{3}$ and varied in diameter between 10 and 100 \AA{}. With increasing temperature, the susceptibility increased from its initial value to a maximum at a temperature ${T}_{B}$ followed by a hyberbolic decrease. A theory based on the relaxation time for single-domain particles $\ensuremath{\tau}={\ensuremath{\tau}}_{0}{e}^{\frac{KV}{kT}}$ ($K$ is the anisotropy energy, $V$ is the particle volume) quantitatively explains the data. At $T=0$ all the particles are blocked by the anisotropy barriers. As the temperature is increased the susceptibility increases because particles for which $\ensuremath{\omega}\ensuremath{\tau}l1$ ($\ensuremath{\omega}$ is the angular frequency) are no longer blocked. Above ${T}_{B}$ all the particles are unblocked and the susceptibility is characteristic of superparamagnetism. Analysis of the data yields information about the particle volume distribution function and a value for the effective anisotropy energy.
Meastri: A hybrid analytical/monte carlo code for particle transport in solids

Abstract We report on a hybrid analytic/Monte Carlo code for evaluating particle transport in solids. In this code, atomic concentrations in the near surface implanted region of a target material, { N k ( x , t )}, are propogated in time through the method of equivalent atomic stopping (MEAS). The implantation source profiles { P k ( x , t )}, initially obtained from the TRIM code, are propagated along with the { N k ( x , t )}. In addition, TRIM is invoked periodically to provide updated profiles { P k ( x , t )}, since the MEAS procedure includes only first order corrections to the { P k }. The code provides for simultaneous implantation of different atomic species and includes the local mixing model (LMM) for describing buildup to saturation and isotope exchange for implantation of hydrogen and/or other species. Since the MEAS procedure is analytic, both sputtering and diffusion are included in a natural way, and disparate time scales, e.g. for implantation, sputtering and diffusion, are easily accommodated. The code is particularly useful for high fluence implantation. Example calculations for simultaneous C and D implantation into graphite are compared with experimental data obtained from TFTR limiter tiles.
Quantifying transport in numerically generated velocity fields

Abstract Geometric methods from dynamical systems are used to study Lagrangian transport in numerically generated, time-dependent, two-dimensional (2D) vector fields. The flows analyzed here are numerical solutions to the barotropic, β-plane, potential vorticity equation with viscosity, where the partial differential equation (PDE) parameters have been chosen so that the solution evolves to a meandering jet. Numerical methods for approximating invariant manifolds of hyperbolic fixed points for maps are successfully applied to the aperiodic vector field where regions of strong hyperbolicity persist for long times relative to the dominant time period in the flow. Cross sections of these 2D “stable” and “unstable” manifolds show the characteristic transverse intersections identified with chaotic transport in 2D maps, with the lobe geometry approximately recurring on a time scale equal to the dominant time period in the vector field. The resulting lobe structures provide time-dependent estimates for the transport between different flow regimes. Additional numerical experiments show that the computation of such lobe geometries are very robust relative to variations in interpolation, integration and differentiation schemes.
Significance of serum fungal inhibitory factor in dermatophytosis.

An in vitro agar-diffusion system was used to assay human serum for inhibition of Trichophyton mentagrophytes growth. Sera were obtained for 30 adults representative of three major classes of susceptibility to dermatophytosis: (1) immunologically nonexperienced, (2) experienced immune, and (3) chronically infected. Although the three classes represent polar degrees of resistance/susceptibility to infection, there was no significant difference in the inhibitory power of their sera. Furthermore, nonexperienced subjects undergoing a primary infection were not found to acquire any increase in serum inhibitory activity, despite the simultaneous acquisition of a strong relative immunity. Nevertheless, other evidence suggests this unknown factor may play a role in defense against dermatophyte infection.
Energy optimization in chiller plants: A novel formulation and solution using a hybrid optimization technique

The central chilled water plant is one of the major power-consuming units of a building. Even small reductions in power consumption could achieve significant energy conservation. Hence, optimization of a chiller plant is necessary for energy savings without compromising the comfort level of the end user. The present work deals with identifying the system parameters and developing a novel formulation for a chiller plant and its optimization using a hybrid optimization technique. The optimization model formulation is based on finding an optimal mix of equipment and operating parameters in the chiller plant for minimum electrical power consumption. It takes into account the performance characteristics of the chillers, cooling towers and pumps, and optimizes the energy consumed based on the required loads and the ambient atmospheric conditions. Sequential quadratic programming combined with the modified branch and bound method was used to develop the hybrid optimization algorithm. A case study is presented fo...
ABIL: An Interactive Microcomputer Program for Calculating Score Ability Estimates from Item Difficulty Statistics:

A computer program is described which generates the number-correct to logit-scaled-score (ability-score) conversion table for a test composed of items precalibrated using Rasch procedures. A graph of the test information function is also produced. The program is written in BASIC for the Apple II Plus microcomputer.
The bacterial nitrate reductases: EPR studies on nitrate reductase A from Micrococcus denitrificans.

EPR studies on nitrate reductase indicate at 80 °K a signal at g=1.985 and g=2.045 attributable to Mo(V). At 15 °K a signal is observed at g=2.016 due to Fe(III) in an unknown symmetry. The reaction of nitrate reductase with nitrate, nitrite or azide results in changes of the Mo(V) signal. Quantitation of the Mo(V) signal intensity accounts for 15% of the chemical molybdenum content. A similar quantitation of the Fe(III) signal intensity indicates equimolarity with enzymatically reducible g=1.9-type resonance. Enzymatic reduction of nitrate reductase and nitrate with sodium dithionite plus benzyl viologen or molecular hydrogen plus hydrogenase results in the disappearance of the initial Mo(V) and Fe(III) signals and the appearance of a temperature-sensitive iron-sulfide absorption with g-values at 2.057, 1.947 and 1.881 when measured at 15 °K. Chemical reduction of nitrate reductase with sodium dithionite also results in loss of the initial Mo(V) and Fe(III) signals but gives a more complex iron-sulfide signal consisting of two different types of iron-sulfide systems. Quantitation of both types of iron-sulfide system indicated they are present in approx. equal concentrations. These two iron-sulfide systems may differ in redox potential. These studies support the involvement of iron and molybdenum in nitrate reductase.
Lack of opiate effects on cat C polymodal nociceptive fibers.

Abstract The direct application of preservative-free morphine sulfate (1.5%, 1 ml, 19.8 μmol) or fentanyl (0.06%, 1 ml, 1.07 μmol) on the superficial radial or saphenous nerve of cats did not alter the response of single C polymodal nociceptive fibers (PMNs) to noxious radiant heat stimulation of their peripheral receptive fields. Intravenous administration of fentanyl (100 or 200 μg/kg, 0.179 or 0.358 μmol/kg) also showed a similar lack of effect on the radiant heat evoked responses of single PMNs. Slight changes in the mean latencies following drug administration were recognized, which were not statistically significant. The use of morphine (1.5%, 1 ml, 19.8 μmol) with preservatives (chlorbutanol 0.5% and sodium bisulfite less than 0.1%) caused conduction block of PMNs within 6–15 min. Subsequent washout of the drug resulted in the return of the unitary discharges within 8 min. Lidocaine (0.25 and 0.5%, 10.7 μmol and 21.4 μmol) caused conduction block within 5–18 min. These data support the classically held concept that opiates, in clinically useful concentrations, do not alter peripheral nerve function.
Analytic Bounds on Data Loss Rates in Mostly-Covered Mobile DTNs

We derive theoretical performance limits of densely covered delay-tolerant networks (DTNs). In the DTN model we study, a number of fixed (data collector) nodes are deployed in the DTN region where mobile (data generator) nodes move freely in the region according to Brownian motion. As it moves, each mobile is assumed to continuously generate and buffer data. When a mobile comes within the communication coverage range of a data collector node, the mobile immediately and completely uploads its buffered data to the data collector node, and then resumes generating and buffering its data. In this paper, we first derive analytic bounds on the amount of time a mobile spends without communication coverage. Then, using these derived bounds, we derive sufficient conditions on node density that statistically guarantee that the expected amount of time spent in the uncovered region remains below a given threshold. Additionally, we derive sufficient conditions on node density to keep the probability of buffer overflow below a given tolerance.
Passive Control of Noise and Instability in a Swirl-Stabilized Combustor With the Use of High-Strength Porous Insert

Swirl-stabilized combustion and porous inert medium (PIM) combustion are two methods that have been used extensively, although independently, for flame stabilization. In this study, the two concepts are combined so that the porous insert serves as a passive device to mitigate combustion noise and instabilities. A properly shaped PIM is placed within the combustor to directly influence the turbulent flow field and vortical and/or shear layer structures associated with the outer recirculation zone and inner recirculation zone. After presenting the concept, the paper provides a conceptual understanding of the changes in the mean flow field caused by the PIM. Combustion experiments were conducted at atmospheric pressure using HfC/SiC coated open-cell foam structures of different pore sizes and shapes. Measurements of sound pressure level (SPL) and CO and NOx emissions were taken for different equivalence ratios and reactant flow rates. Combustion mode and PIM geometry to decrease the SPL are identified. Results show that the porous insert can reduce combustion noise without adversely affecting NOx and CO emissions. Experiments show that the proposed concept can also mitigate combustion instabilities encountered at high reactant flow rate.Copyright © 2011 by ASME
The Behavior of "Magnetic" Electron Multipliers as a Function of Frequency

This paper consists of a theoretical and experimental study of the frequency variation of gain of magnetic electron multipliers. It is shown that, for multipliers of the type studied, the behavior as a function of over-all electron transit angle is very similar to that observed for electrostatic electron multipliers previously described. Up to frequencies of about 500 megacycles, loss in gain can be ascribed to a spread in transit angle resulting from the emission velocities of secondary electrons and the varying paths of electrons through the stages of the multiplier. From the results given, it is possible to predict the useful upper frequency limit of a magnetic electron multiplier of the type studied.
Reduction of hygrothermal transverse stresses in unidirectional hybrid composites under cyclic environmental conditions

When fiber-reinforced polymer plates are exposed to cyclic environmental conditions, polymer matrix absorbs or desorbs continuously the moisture due to the variation in service temperature and relative humidity. Both temperature and moisture concentration produce an important hygrothermal transverse stresses, which are maximum on both edges of the composite plates. These transverse stresses which are more important at first times of moisture diffusion, can produce a probable damage of composite plates. To extend the durability of our composite plate, interplay hybrid composites are adopted to reduce the transverse stresses on edges. Therefore, a variation of the relationship between thicknesses of unidirectional hybrid composites constituents AS/3501-5 and T300/5208 is carried out in order to find minimal transverse stresses. This thicknesses variation enables us to find the best configuration which gives favourable service conditions of our hybrid composite, i.e., to predict firstly a considerable reduction of hygrothermal transverse stresses at both edges of our hybrid plate, secondly to reduce or to attenuate the edge effect developed in 6 days and 6 weeks periods.
Modification of Spontaneous Emission of Quantum Dots: Purcell Effect in Semiconductor Microcavities

We study the spontaneous emission of a quantum dot embedded in a cavity. Purcell and local-field effects are investigated using the coupled dipole method and a comparison with a continuous medium approach is presented.
Identification of the membrane receptor for the complement fragment C3d by means of a monoclonal antibody.

The B2 antigen characterized by means of a monoclonal antibody (14) is a 140,000 Mr protein expressed only in certain stages of the differentiation of lymphocytes of the B lineage. Here we examine the relationship between B2 and the membrane complement receptor type 2 (CR2) for the complement fragment C3d (11, 12), which is also associated only with B cells. Both phenotypic markers are distributed in a similar manner among B cell malignancies and, as shown here, among established cell lines. A polypeptide with binding affinity for C3d was isolated from the membrane of B2-positive cells, i.e., tonsil lymphocytes and Raji cells. We found that this C3d-binding protein not only had the same Mr and isoelectric point (pI) as the B2 antigen, but that it was recognized by the monoclonal antibody to B2. However, anti-B2 does not mask the ligand-binding site of CR2 since it does not prevent the interaction of the purified 140,000 Mr polypeptide with immobilized C3d. Rosette formation between tonsil lymphocytes and erythrocyte intermediates bearing C3d was specifically inhibited by anti-B2. In the case of Raji cells, rosette formation was strongly inhibited only when the lymphocytes were sequentially treated with anti-B2 and with a polyclonal antibody against mouse Ig. In short, B2 and CR2 have a similar distribution among normal and malignant cells, have the same Mr and pI under denaturing conditions, and react with a single monoclonal antibody. We conclude that B2 is identical to CR2.
Duplication of 11p14.3-p15.1 in a mentally retarded proband and his mother detected by G-banding and confirmed by high-resolution CGH and BAC FISH

Abstract A 10-year-old African–American male has been followed since 2 years of age due to his mental retardation, severe behavioral problems, and dysmorphism. Conventional cytogenetic analysis, chromosome painting, high-resolution comparative genomic hybridization (HR-CGH), and bacterial artificial chromosome fluorescent in situ hybridization (BAC FISH) revealed an apparent duplication in the short arm of a chromosome 11, dup(11)(p14.3p15.1), seen also in his mentally retarded mother. The proband had moderate to severe mental retardation, a history of IUGR, infantile hypotonia, FTT, exotropia, inguinal hernia repair, and several dysmorphic features. His mother had mild mental retardation, a history of impulsivity, assaultive outbursts, and similar dysmorphism. Although G-banding and FISH indicated a duplication, HR-CGH confined the localization of material to bands 11p14–11p15 and aided the selection of locus-specific BAC clones to more precisely characterize the duplicated region. To our knowledge, the results represent the first example of a familial, cytogenetically visible duplication of euchromatin in 11p that excludes the Beckwith–Wiedemann syndrome critical region. It is possible that one or more genes had been disrupted at the breakpoints of the above structural chromosomal rearrangement giving rise to the present phenotype.
Age pigments, cell loss and hippocampal function.

Abstract The specific aims of this study were to perform direct correlational analyses of age differences in learning, short-term memory and arousal in relation to cell loss and lipofuscin increase in the hippocampus CA1 zone and in visual area 17 of the Fisher 344 rat. The following tentative conclusions can be made from the results presented in this study: (1) significant age differences in 2 and 6 hour passive-avoidance retention or memory between mature and old rats were related to non-significant age differences in days to criterion learning, starting latencies, running distance and time in original approach learning, and (2) significant age differences in 2 and 6 hour retention of old, compared to mature rats were correlated significantly with loss of neurons, and very significantly with increases in intraneuronal lipofuscin in the hippocampus CA1 zone and in visual area 17.
Status and needs of infrared optical property information for optical designers

The availability and quality of the existing data on popular materials are reviewed. The needs and the possibilities for meeting these needs are then discussed. I .
Accuracy of M mode echocardiographic measurements of the left ventricle

Abstract M mode echocardiography provides quantitative information regarding the dimensions of the left ventricle. To compare left ventricular dimensions obtained by several methods from the M mode echocardiogram with actual dimensions, M mode echocardiograms of the inferventricular septum and left ventricular posterior wall were recorded simultaneously with sonomicrometer crystal signals of the left ventricular minor axis dimension in 12 instrumented open chest dogs. End-diastolic dimension from the M mode echocardiogram was measured (1) at the onset of the QRS complex, (2) at the peak of the R wave of the electrocardiogram, and (3) as the largest diameter. End-systolic dimension was measured from the M mode echocardiogram (1) at the nadir of septal motion, (2) at the peak of posterior wall motion, and (3) as the smallest dimension. End-diastolic dimension measured either at the onset of the QRS complex or at the peak of the R wave did not differ from that measured from the sonomicrometer crystal signals. However, end-diastolic dimension measured as the largest diameter was significantly larger than that measured from the sonomicrometer crystal signals (p On the M mode echocardiogram, end-diastolic dimension is most accurately measured at the onset of the QRS complex or at the peak of the R wave of the electrocardiogram. End-systolic dimension is most accurately measured at the nadir of posterior motion of the interventricular septum when septal motion is normal. These data support the recommendations of The American Society of Echocardiography on attempts to quantitate left ventricular minor axis dimensions from the M mode echocardiogram.
SCVIR 2002 Film Panel Case 6: Hematuria Caused by Ureteroarterial Fistula

A 60-year-old woman presented with gross hematuria from a nephrostomy tube placed 1 month previously into her left upper urinary tract. Her medical history was remarkable for chronic stricture of the left ureter that had been managed previously with a retrograde left ureteral stent. In addition, the patient had atherosclerotic peripheral vascular disease which had been treated 3 years before admission with an aortobifemoral bypass graft. One month before admission, the graft became infected with Staphylococcus epidermidis. The graft infection was managed by surgical placement of a left-axillary-to-left-profunda synthetic graft coupled with the placement of a left-femoral-to-right-femoral cryopreserved vein graft. The infected synthetic aortobifemoral bypass graft was then excised. Because the patient had experienced continued claudication with a patent aortobifemoral bypass graft, the surgeon was concerned that the left-axillary-toleft-profunda bypass graft would not provide adequate inflow to support both lower extremities. Therefore, it was elected to place an in-line aorto–left common femoral cryopreserved vein graft at the time of infected prosthetic graft explantation. Postoperatively, the patient developed left flank pain. Ultrasonography showed left hydronephrosis. Attempted retrograde replacement of the left-sided ureteral stent was unsuccessful, and a left-sided percutaneous nephrostomy was performed. The patient was discharged home in stable condition, but returned 1 month later with bloody urine draining from her nephrostomy tube. Physical examination revealed a chronically ill–appearing woman in no acute distress. She was afebrile and mildly tachycardic to 100 bpm with a blood pressure of 104/60 mmHg. Laboratory evaluation results were as follows: hematocrit, 34% (normal, 36%–46%); white blood cells, 8.3 10/L (normal, 3.4–10 10/L); platelets, 250 10/L (normal, 140–450 10/L); creatinine, 1.2 mg/dL (normal, 0.6–1.2 mg/dL); prothrombin time, 12.8 seconds (normal, 11.0–14.5 sec); and international normalized ratio, 1.1 (normal, 0.8–1.2). To evaluate the source of bleeding, the patient underwent abdominal and pelvic computed tomography (CT) (Fig 6.1), left nephrostography (Fig 6.2), and angiography (Figs 6.3–6.5).
Localization of neuroendocrjne tumors of the pancreas

The diagnosis of neuroendocrine tumors of the pancreas is based on clinical, biochemical, and ultrastructural data. The different radiological modalities are employed only for localization, except in the case of nonftinctioning neoplasms, for which a differential diagnosis from adeno-carcinoma can be suggested based on the radiographic images. Generally, the initial evaluation should consist of the noninvasive studies and should be complemented by angiography and, in cases of functioning neoplasms, with pancreatic venous sampling if the preliminary findings are inconclusive. However, the localizing work-up should be terminated when the information obtained is sufficient to determine the therapy that will follow. If the ultrasonic or computed tomographic findings preclude surgical resection, further work-up is obviously unnecessary.
Interaction of the long-wave cones and the rods to produce color sensations.

The duplicity theory states that cones produce photopic or color vision, whereas the rods produce scotopic or colorless night vision. This paper reports experimental findings which demonstrate the capacity of the rods to interact with the long-wave cones to produce color sensations. Radiances of 546 and 450 nm that excited only the rods, and radiances of 656 nm that excited only the long-wave cones were determined. When the rods and long-wave cones were selectively excited with the minimum radiance necessary to see form, the observers reported seeing a large variety of color sensations. These observers also reported the same variety of color sensations at greater radiances when the rods and long-wave cones were selectively excited. Color sensations produced by the excitation of rods and long-wave cones were independent of the wavelength used to excite the rods. Color sensations produced by rods and long-wave cones were identical, except for slight differences of brightness and sharpness, to the color sensations produced by 656 and 495±5 nm light when both were above cone threshold. Therefore, under the described conditions, the rods can be as much a part of the human color-producing system as the cones. All of the above results can be explained by Land’s retinex theory of color vision.
Reading too much between the lines : illusory correlation and the word association implications test

Abstract We examined the illusory correlation phenomenon with the Word Association Implications Test (WAIT), a task where diagnoses and signs are causally connected due to priming effects. The WAIT is an analogue to clinical assessments in which subjects “read between the lines” of target persons’ word associations which have been primed by fantasized scripts. 164 undergraduates were randomly assigned to study WAIT protocols with either 0, 30, 70, or 100% of the targets veridically identified. Following subjects’ examination of WAIT protocols, we assessed their incidental learning of valid diagnostic clues (i.e., their clue schemata). Subjects given no veridical diagnoses showed minimal incidental learning. However, those given 30, 70, and 100% veridical diagnoses showed equivalent incidental learning of diagnostic clues and all exceeded an intuition (no experience) comparison group. The results suggested that an illusory correlation operated even when clues and diagnoses have causal, not just contingent, connection. Successful judges must contend not only with others’ tools for avoiding prediction but with their own tendencies to read too much between the lines.
Quantitative Analysis of Macular Holes with Scanning Laser Tomography

Objective: The purpose of the study is to establish objective, quantitative, and reproducible three-dimensional analysis for macular holes with scanning laser tomography and to correlate measurements with visual acuity. Design: The authors performed a cross-sectional, nonrandomized study. Participants: The authors examined 28 full-thickness macular holes of 23 patients aged 61 to 84 years. Intervention: Confocal infrared imaging with scanning laser tomography using the TopSS (790 nm, 10° field) three-dimensional measurements and macular hole analysis were performed. Main Outcome Measures: Area, depth, and volume parameters for both macular holes and rims were obtained in two ways: (1) reference plane for analysis equal to height of the retina (offset surface distance [OSD] 0) or (2) equal to height of the surrounding edematous rim of the hole (OSD user). Correlation of measurements with visual acuity and groups of macular holes was performed. Reproducibility from three image series per subject and intraobserver variability from ten measurements in four subjects were computed. Results: Scanning laser tomography could detect macular hole and rim features in all subjects. Infrared images provided clinically useful information that may help explain macular hole pathophysiology. Based on quantitative, three-dimensional measurements, holes were assigned to four groups: large, small, shallow, and average. Groups varied significantly ( P P Conclusions: Scanning laser tomography is a reproducible three-dimensional imaging technique providing objective and quantitative clinical information in assessing, grouping, and managing macular holes. By setting the OSD to rim height, additional information of rim height and hole volume was provided and correlated with visual acuity. In addition, more reliable differences among macular hole groups were found. Axial measurements such as macular hole depth, volume, and rim height may be more important for visual acuity than hole area indicating their possible predictive value for outcome measures.
Lateral stimulus-response compatibility effects in the oculomotor system

Abstract Eye movement reaction time (RT) was measured in simple and choice RT situations in which monaural tones were presented to the left or right ear. In the choice RT conditions, tones of one frequency signaled a left looking response and tones of another frequency signaled a right looking response. In the simple RT condition, tones were presented in 2 blocks signaling right or left looking responses. RTs were measured by electro-oculogram (EOG), with electrodes placed over the outer canthus of each eye. In the choice RT condition, oculomotor RTs were faster when the tones signaling right or left looking were presented in the ears corresponding to the direction of looking than when they occured in the opposite ear. No such correspondence was present in the simple RT condition. S s also performed a manual choice RT task. The lateral stimulus- response (S-R) compatibility effects obtained confirmed previous findings and were of the same magnitude as those obtained in the oculomotor response modality. Asymmetry in correlations between oculomotor and manual compatibility effects suggests differential hemispheric mediation.
Purified progenitor/The International Journal of Cell Cloning: Background, feasibility, and prospects for clinical transplantation

CD34 monoclonal antibodies recognize a transmembrane phosphoglycoprotein selectively expressed within the lymphohematopoietic system on progenitor and The International Journal of Cell Cloning. The CD34 molecule is heavily glycosylated and strongly negatively charged. Sialic acids contribute to the anomalous electrophoretic mobility corresponding to an apparent molecular weight of -110 kilodaltons. However, the molecular weight of the CD34 polypeptide predicted from the sequences of the recently cloned human and murine CD34 genes is only about 40 kilodaltons. The intracellular tail of the CD34 molecule is a substrate for protein kinase C and other protein kinases, suggesting that CD34 plays a role in signal transduction. The highly-charged N-terminal extracellular portion of the molecule may mediate intercellular adhesion. The sequence of the CD34 gene is as yet unique, without strong homology to any previously know molecule. To date, the sequence has not provided major clues as to the function of the protein product. The human CD34 gene has been localized to chromosome 1 q32, which is not a frequent breakpoint in hematologic malignancies. Outside the lymphohematopoietic system, CD34 was detected initially only on endothelial cells, although recently an alternatively spliced CD34 isoform with a shortened intracellular tail has been found to be expressed strongly in mouse brain by nucleic acid hybridization. Recent work also suggests that CD34 is expressed on precursors of hematopoietic stromal cells. CD34 monoclonal antibodies are widely used for identification and purification of human lymphohematopoietic progenitor/stem cell populations. The unique selective expression of CD34 on this cell compartment has also stimulated use for successful primate and human “stem cell BMT,” and recent work suggests that this clinical application will be productively expanded to stem cell selection from cord blood and peripheral blood.
Autonomic block, cardiovascular depression and histamine release produced by polymyxin B in the cat

The present study quantifies the autonomic block, the cardiovascular depression and the histamine releasing effects of polymyxin B in nine anaesthetized cats. The dose requirements for 50 per cent depression of the mean arterial blood pressure, the bradycardiac response to vagal stimulation, and the contraction of the nictitating membrane elicited by pre-ganglionic and post-ganglionic stimulation of the cervical sympathetic trunk have a narrow range of scatter, being of the order of 6--12 mg.kg-1 of the polymycin B base. The neuromuscular blocking dose (ED50), previously determined and hereby confired, also falls in the same range. Bradycardia and possibly histamine release are also observable. The relatively unremarkable effect of polymyxin B on the heart rate can be attributed to the balance between the vagal, sympathetic and ganglionic blocks, as well as the possible histamine release. All effects are long-lasting. Thus lack of tissue specificity makes it implausible to explain the neuromuscular and the cardiovascular effects of polymyxin B solely by the cholinergic mechanism of action. Ganglionic block and histamine release do not completely explain hypotension induced by polymyxin B. We propose that all biological effects of polymyxin B derive from a common mechanism of action, which may be its antimembrane antibacterial action. We would like to alert anaesthetists to the possiblity that polymyxin B may cause severe multiple organ system depression, in addition to neuromuscular block.
Identification of oda6 as a Chlamydomonas dynein mutant by rescue with the wild-type gene

We find that two Chlamydomonas outer arm dynein assembly loci, oda6 and oda9, are located on the left arm of linkage group XII, in the vicinity of the previously mapped locus for a 70,000 Mr dynein intermediate chain protein. Restriction fragment length polymorphism mapping indicates that this dynein gene is very closely linked to the oda6 locus. A cDNA clone encoding the 70,000 Mr protein was isolated, sequenced, and used to select genomic clones spanning the corresponding locus from both wild-type and oda6 libraries. When wild-type clones were introduced into cells containing an oda6 allele, the mutant phenotype was rescued, while no rescue was observed after transformation with oda6 clones. Genetic analysis further revealed that newly introduced gene copies were responsible for the rescued phenotype and thus confirms that ODA6 encodes the 70,000 Mr dynein intermediate chain protein. The inability of oda6 mutants to assemble any major outer arm dynein subunits shows that this protein is essential for assembly of stable outer dynein arms. This is the first use of transformation with a wild-type gene to identify the product of a Chlamydomonas mutant.
The origin of human trisomy: a study of heteromorphisms and satellite associations.

SUMMARY The origin of the additional chromosome was studied in 45 trisomic-21 Down-syndrome patients. In 17 patients the additional chromosome was maternal, in 2 it was paternal and in the remaining 26 the parental origin could not be determined. Acrocentric chromosome association was studied in parents of Down-syndrome offspring and in parents of spontaneous abortions that were trisomic for an acrocentric chromosome. Parents of trisomic 16 abortuses and parents of triploid and chromosomally normal abortuses were used as controls. No increased association index was found for the specific acrocentric chromosome involved in the trisomy, either for the liveborn or for the aborted trisomies. However, the overall association index of the parent in whom the non-disjunctional event leading to the acrocentric trisomy occurred was increased by comparison with that of the parent in whom non-disjunction did not occur and with that of the controls. The reasons why we consider satellite associations to play an insignificant role in the aetiology of non-disjunction are discussed.
Weathering rinds and rock coatings from an Arctic alpine environment, northern Scandinavia.

Coarse rock debris exposed in the subaerial environment of northern Sweden displays the development of a wide variety of surface coatings. These include weathering rinds as well as a great diversity of geochemical coatings, including those dominated by Ca, Fe, Si, and Al. Each of these types of rock coatings displays a high degree of geochemical complexity. The weathering rinds exhibit both geochemical and morphologic changes to the parent rock cores, including extensive dissolution, oxidation, and hydration as well as disaggregation, fracturing, and cementation by secondary geochemical coatings. Chemical breakdown of the rock to form weathering rinds includes loss of K, Si, Mg, and Ca and buildup of Fe. Weathering rinds are fundamentally the result of dissolution, as no clay minerals were identified in the rinds. Rock coatings are distinguished from rinds by their clear accretionary nature. Despite the distinction made between weathering rinds and rock coatings, it is important to note that often the two are intimately related. The presence of rock coatings as well as weathering rinds on rock surfaces amplifies the important role played by geochemical processes in the Arctic alpine climate of northern Sweden in particular, as well as its significance in landscape evolution in such environments in general.
Different HECT domain ubiquitin ligases employ distinct mechanisms of polyubiquitin chain synthesis

Individual ubiquitin (Ub)-protein ligases (E3s) cooperate with specific Ub-conjugating enzymes (E2s) to modify cognate substrates with polyubiquitin chains. E3s belonging to the Really Interesting New Gene (RING) and Homologous to E6-Associated Protein (E6AP) C-Terminus (HECT) domain families utilize distinct molecular mechanisms. In particular, HECT E3s, but not RING E3s, form a thiol ester with Ub before transferring Ub to the substrate lysine. Here we report that different HECT domain E3s can employ distinct mechanisms of polyubiquitin chain synthesis. We show that E6AP builds up a K48-linked chain on its HECT cysteine residue, while KIAA10 builds up K48- and K29-linked chains as free entities. A small region near the N-terminus of the conserved HECT domain helps to bring about this functional distinction. Thus, a given HECT domain can specify both the linkage of a polyubiquitin chain and the mechanism of its assembly.
Assessment of Cognitive-Communication Disorders in Adults with Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) has been in the news lately, particularly mTBI in school-aged children, professional athletes, and service members and veterans. College students have received le...