cssi/SciSciGPT-SciSciNet huggingface dataset:
Studies on soluble ribonucleic acid of rabbit liver III. Preparation and properties of rabbit-liver soluble RNA

Abstract Soluble RNA has been prepared in relatively large amounts from rabbit liver by a procedure involving extraction of the “pH-5 enzymes” with hot NaCl. The product is highly homogeneous with respect to molecular size and heterogeneous with respect to biological activity inasmuch as it can act as acceptor for at least 15 different activated amino acids. The nucleotide composition of rabbit-liver soluble RNA has been determined quantitatively by column chromatography, under conditions which permit the separation of 5 minor components: (i) 5-hydroxymethylcytidine ribotide; (ii) 6-methylaminopurine ribotide; (iii) 2-dimethylamino-6-hydroxypurine ribotide; (iv) 1-methylguanine ribotide; and (v) 5-ribosyluracil ribotide; in addition to the 4 major ones: cytidylic acid; adenylic acid; guanylic acid; and uridylic acid. The minor components represent approx. 10% of the total nucleotides. Soluble RNA is markedly resistant to enzymic degradation by a variety of RNA-ases. The significance of these findings is discussed.
Structural studies of the RNA pseudoknot required for readthrough of the gag-termination codon of murine leukemia virus

Retroviruses, such as murine leukemia virus (MuLV), whose gag and pol genes are in the same reading frame but separated by a UAG stop codon, require that 5–10 % of ribosomes decode the UAG as an amino acid and continue translation to synthesize the Gag-Pol fusion polyprotein. A specific pseudoknot located eight nucleotides 3′ of the UAG is required for this redefinition of the UAG stop codon. The structural probing and mutagenic analyses presented here provide evidence that loop I of the pseudoknot is one nucleotide, stem II has seven base-pairs, and the nucleotides 3′ of stem II are important for function. Stem II is more resistant to single-strand-specific probes than stem I. Sequences upstream of the UAG codon allow formation of two competing structures, a stem-loop and the pseudoknot.
Crystal structure of Escherichia coli penicillin-binding protein 5 bound to a tripeptide boronic acid inhibitor: a role for Ser-110 in deacylation.

Penicillin-binding protein 5 (PBP 5) from Escherichia coli is a well-characterized d-alanine carboxypeptidase that serves as a prototypical enzyme to elucidate the structure, function, and catalytic mechanism of PBPs. A comprehensive understanding of the catalytic mechanism underlying d-alanine carboxypeptidation and antibiotic binding has proven elusive. In this study, we report the crystal structure at 1.6 A resolution of PBP 5 in complex with a substrate-like peptide boronic acid, which was designed to resemble the transition-state intermediate during the deacylation step of the enzyme-catalyzed reaction with peptide substrates. In the structure of the complex, the boron atom is covalently attached to Ser-44, which in turn is within hydrogen-bonding distance to Lys-47. This arrangement further supports the assignment of Lys-47 as the general base that activates Ser-44 during acylation. One of the two hydroxyls in the boronyl center (O2) is held by the oxyanion hole comprising the amides of Ser-44 and H...
Primate locomotor pattern repetitions, program clocks, and orientation to light

Remarkable locomotor pattern repetitions by small nocturnal primates in 122-cm activity wheels occurred during 4-hour light cycles with simulated twilights. Some of the repetitions owed their genesis almost entirely to a night-to-night concurrence of endogenous timing programs. Others depended on strong tendencies of the animals to orient relative to the position of light sources and enclosure environment. Still others were based partly on influences of twilight illuminance level on speed of locomotion.
The use of chorionic gonadotropin to induce laboratory spawning of the Atlantic croaker, Micropogon undulatus , with notes on subsequent embryonic development

We studied the feasibility of spawning and rearing the Atlantic croaker,Micropogon undulatus, in the laboratory. Adult croaker were collected during mid-October, 1972, placed in flowing seawater holding tanks, and administered injections of either 125 or 250 I.U. of chorionic gonadotropin three times per week for three weeks. An apparent period of latency (6–7 days) was observed between the initial hormone injections and successful ovulation. Fish dosed at the 125 I.U. level were successfully spawned and eggs and larval development monitored. Larvae were carried through to 4 days after hatching when mass mortalities occurred, apparently as a result of nutritional deficiencies.
Enhanced Seebeck coefficient from carrier-induced vibrational softening

Through their electron-lattice interactions, localized carriers reduce vibrational stiffness constants in their surroundings. States with a large electronic polarizability (e.g., multiatomic localized states and states of a singlet bipolaron formed of degenerate electronic orbitals) induce exceptionally large softening. This carrier-induced softening augments the Seebeck coefficient of solids whose carriers hop between these localized states through two separate effects. One enhancement is due to a localized carrier inducing an increase in a solid's vibrational entropy. The other contribution is proportional to the vibrational energy transferred with a carrier as it hops. Both softening contributions are independent of the carrier density. The magnitudes and temperature dependencies of these contributions to the Seebeck coefficient indicate the electronic polarizabilities of the localized states and the vibrational modes to which they are coupled. Measured softening enhancements of Seebeck coefficients are sometimes large enough (e.g., g200 \ensuremath{\mu}V/K measured at 300 K in boron carbides) to significantly increase the efficiency of thermoelectric energy conversion.
Quadrature Subharmonic Coupled Oscillators for a 60GHz SiGe Scalable Phased Array

This paper describes an integrated coupled oscillator array in SiGe for millimeter wave applications. The design focuses on scalable radio architectures where multiple dies are tiled to form larger arrays. A 2 times 2 oscillator array for a 60GHz transmitter is designed with integrated power amplifiers and antennas. The 2 times 2 array demonstrates a 200MHz locking range and 1 times 4 array formed by two adjacent chips has a 60MHz locking range. The phase noise of the array is below -110dBc/Hz at a 1MHz offset
Myelin breakdown in Alzheimer's disease: a commentary.

The article by Barzokis is a well-argued, insightful thesis that challenges us to consider novel views of the aging and diseased brain. The particular strength of this article is that it should succeed in bringing to the forefront of our thinking an appreciation for the high degree of metabolic activity and concomitant energy cost associated with maintaining a heavily myelinated brain and how aging or aging with disease may impact on or be impacted by this process. White matter has a number of essential metabolic processes that are ongoing throughout life yet the vascular supply is less extensive than the gray matter. This relationship between demand for nutrient support and limited access to nutrients requires development of storage devices (e.g. high ferritin content of oligodendrocytes for iron storage) and increases the likelihood of functional failure following any event associated with compromise in nutrient delivery. The types of neurological events in which white matter involvement is seen are detailed in the Bartzokis article. However, frequently the white matter involvement is considered secondary or of less neurological consequence than accompanying gray matter damage. Perhaps, in view of the strong supporting data discussed in the Bartozkis article, the white matter involvement will be given greater consideration. As argued, continual degradation of white matter and fragmentation of myelin could result in continued or exacerbation of an inflammatory reaction that could prove resistant to therapeutic interventions that do not specifically target this region. The relationships to memory consolidation and myelination are particularly noteworthy in considering myelin deficits and cognitive function in Alzheimer’s disease (AD). Although the article was necessarily focused on white matter and hence white matter oligodendrocytes, the potential contribution of gray matter oligodendrocytes to myelin, cholesterol and iron metabolism are also relevant to the concepts set forth. The argument that oligodendrocytes have a high energy requirement and associated high iron requirement can be supported further than the studies referenced in the Bartzokis
Blastic variant of mantle-cell lymphoma: cytomorphologic, immunocytochemical, and molecular genetic features of tissue obtained by fine-needle aspiration biopsy.

Mantle-cell lymphoma (MCL) is a rare type of non-Hodgkin's lymphoma that has a moderately aggressive clinical course, generally between that of low-grade and of intermediate-grade lymphomas. However, a small subset of MCLs, the so-called “blastic” variant, exhibits a poor prognosis and an aggressive clinical course. We describe a case of blastic MCL that occurred in a 64-yr-old man and that was diagnosed and accurately subclassified as blastic MCL on the basis of a fine-needle aspiration (FNA) biopsy. The aspirate smears showed a monotonous population of intermediate-sized lymphocytes with irregular nuclear contours, finely dispersed nuclear chromatin, and inconspicuous nucleoli. Material was obtained by FNA for ancillary studies (immunocytochemical stains, flow cytometry, cytogenetics, image analysis, and molecular studies) that supported the diagnosis of blastic MCL. Surgical biopsy confirmed the diagnosis. These findings underscore the utility of FNA in diagnosing lymphomas, particularly when the cytomorphologic examination is combined with appropriate ancillary studies. Diagn. Cytopathol. 1998;19:59–62. © 1998 Wiley-Liss, Inc.
Purification of all thirteen polypeptides of bovine heart cytochrome c oxidase from one aliquot of enzyme Characterization of bovine fetal heart cytochrome c oxidase

A protocol has been worked out for separating all thirteen different polypeptides in the beef heart cytochrome c oxidase complex from a single aliquot of enzyme. This involves an initial separation of polypeptides by gel filtration on a Biogel P-60 column in SDS, a step which purifies subunits CIV and CVIII and gives mixtures of CV+CVI, ASA, AED and STA, as well as CVII, CIX and IHQ. These mixtures are then resolved by reverse-phase high-performance liquid chromatography. The separation procedures have been applied to fetal heart cytochrome c oxidase of gestation between 100 and 200 days. No differences were found in the N-terminal sequences of any of the cytoplasmically made subunits or in the entire sequence of CIX between late fetal and adult forms of the enzyme.
Nitrate and Nitrite Toxicity to Salmonoid Fishes

(1974). Nitrate and Nitrite Toxicity to Salmonoid Fishes. The Progressive Fish-Culturist: Vol. 36, No. 2, pp. 86-89.
Get out--and stay out.

Leaving the safety of home exposes our vulnerabilities. In this issue of Blood , Uy and coauthors explore the clinical benefit of interrupting the protective niches in which leukemia cells live in an effort to enhance the benefit of chemotherapy in treating patients with acute myeloid leukemia (AML). 1
Giant anisotropies in the dielectric properties of quasi‐epitaxial crystalline organic semiconductor thin films

We have measured the indices of refraction and dielectric constants along different directions in thin films of the crystalline organic semiconductor compound 3, 4, 9, 10 perylenetetracarboxylic dianhydride (PTCDA). The films were deposited via organic molecular beam deposition, resulting in single‐crystalline, ‘‘quasi‐epitaxial’’ films. Due to inherent asymmetries in the molecular crystal structure, film ordering results in giant anisotropies in their dielectric properties. For example, the index of refraction measured at a wavelength of λ=1.064 μm in the direction perpendicular to the substrate plane is n⊥ = 1.36 ± 0.01, whereas parallel to the plane, n∥=2.017±0.005, resulting in an index difference of Δn=0.66. Furthermore, the low‐frequency dielectric constant of the films is e⊥ = 1.9 ± 0.1 and e∥ = 4.5 ± 0.2. To our knowledge, these are the largest anisotropies ever measured for thin films. We discuss a guided wave polarization‐selective device which takes advantage of the large dielectric anisotropie...
Charge density dependent two-channel conduction in organic electric double layer transistors (EDLTs)

A transport model based on hole-density-dependent trapping is proposed to explain the two unusual conductivity peaks at surface hole densities above 10(13) cm(-2) in rubrene electric double layer transistors (EDLTs). Hole transport in rubrene is described to occur via multiple percolation pathways, where conduction is dominated by transport in the free-site channel at low hole density, and in the trap-site channel at larger hole density.
Leveraging HRM to enrich competitive intelligence

This exploratory investigation into the intersection of competitive intelligence (CI) and human resource management (HRM) begins by reviewing the concept of competitive intelligence which includes the acquisition, analysis, and dissemination of information. To do so, relevant theoretical perspectives emanating from several disciplines (including strategy, law, and human resource management) are reviewed. Then, a number of human resource management solutions that address the four barriers to strategic information diagnosis identified by Boettcher and Welge (1994) are presented. The effects on research and practice of unifying HRM and CI are also discussed. © 1997 John Wiley & Sons, Inc.
Effect of Mesophase Order on the Dynamics of Side Group Liquid Crystalline Polymers

Rheology and X-ray scattering were employed to probe the viscoelastic properties and structural transitions of model cyano-biphenyl-based side-group liquid−crystalline polymers (SGLCPs) with molecular weights ranging from 91 to 1900 kg/mol. Temperature-dependent rheological data show a rapid change in dynamics over a small temperature range. Small-angle X-ray scattering reveals these changes to be associated with an isotropic to smectic transition with an appreciable biphasic region. The presence of a biphasic region is attributed to inhomogeneity in chain structure resulting from incomplete attachment of mesogens to every monomeric unit in the SGLCP polymer. While isotropic and smectic phase data may be separately time−temperature shifted to create master curves for the individual phases, we argue against attempts to achieve superposition between the two phases in the high-frequency regime, since smectic ordering may not simply slow the dynamics but also increase the modulus of the sample. Molecular weight has a strong influence on rheology in the isotropic phase, where an entanglement plateau emerges; however, the smectic-phase rheology is dominated by the layer structure and is fairly insensitive to molecular weight.
Oxygen exchange between uranium oxides and water

Abstract The exchange of 18O between liquid water and various uranium oxides has been studied at temperatures up to the critical temperature of water. Uranium dioxide and U3O8 undergo oxygen exchange only at elevated temperatures, whereas uranium trioxide is found to exchange oxygen with liquid water to a readily measurable extent even at 25°C; in the latter case exchange is complete in 4 hr at 100°C.
Are judgments of learning made after correct responses during retrieval practice sensitive to lag and criterion level effects

Although successful retrieval practice is beneficial for memory, various factors (e.g., lag and criterion level) moderate this benefit. Accordingly, the efficacy of retrieval practice depends on how students use retrieval practice during learning, which in turn depends on accurate metacognitive monitoring. The present experiments evaluated the extent to which judgments of learning (JOLs) made after correct responses are sensitive to factors (i.e., lag and criterion level) that moderate retrieval practice effects, as well as which cues influence JOLs under these conditions. Participants completed retrieval practice for word pairs with either short or long lags between practice trials until items were correctly recalled 1, 3, 6, or 9 times. After the criterion trial for an item, participants judged the likelihood of recalling that item on the final test 1 week later. JOLs showed correct directional sensitivity to criterion level, with both final test performance and JOLs increasing as criterion level increased. However, JOLs showed incorrect directional sensitivity to lag, with greater performance but lower JOLs for longer versus shorter lags. Additionally, results indicated that retrieval fluency and metacognitive beliefs about criterion level—but not lag—influenced JOLs.
ON THE STABILITY OF PICK-UP ION RING DISTRIBUTIONS IN THE OUTER HELIOSHEATH

The "secondary energetic neutral atom (ENA)" hypothesis for the ribbon feature observed by the Interstellar Boundary Explorer (IBEX) posits that the neutral component of the solar wind continues beyond the heliopause and charge exchanges with interstellar ions in the Outer Heliosheath (OHS). This creates pick-up ions that gyrate about the draped interstellar magnetic field (ISMF) lines at pitch angles near 90° on the locus where the ISMF lies tangential to the heliopause and perpendicular to the heliocentric radial direction. This location closely coincides with the location of the ribbon feature according to the prevailing inferences of the ISMF orientation and draping. The locally gyrating ions undergo additional charge exchange and escape as free-flying neutral atoms, many of which travel back toward the inner solar system and are imaged by IBEX as a ribbon tracing out the locus described above. For this mechanism to succeed, the pick-up ions must diffuse in pitch angle slowly enough to permit secondary charge exchange before their pitch angle distribution substantially broadens away from 90°. Previous work using linear Vlasov dispersion analysis of parallel propagating waves has suggested that the ring distribution in the OHS is highly unstable, which, if true, would make the secondary ENA hypothesis incapable of rendering the observed ribbon. In this paper, we extend this earlier work to more realistic ring distribution functions. We find that, at the low densities necessary to produce the observed IBEX ribbon via the secondary ENA hypothesis, growth rates are highly sensitive to the temperature of the beam and that even very modest temperatures of the ring beam corresponding to beam widths of <1° are sufficient to damp the self-generated waves associated with the ring beam. Thus, at least from the perspective of linear Vlasov dispersion analysis of parallel propagating waves, there is no reason to expect that the ring distributions necessary to produce the observed IBEX ENA flux via the secondary ENA hypothesis will be unstable to their own self-generated turbulence.
Finite products of filters that are compact relative to a class of filters

Filters whose product with every countable based countably compact filter is countably compact are characterized.
Weak-Object Image Reconstructions with Single-Shot Digital Holography

Weak object signals with less than one photoelectron per detector pixel can be recovered using off-axis digital holography. We show image reconstructions in simulation with a single exposure.
A fast maximum likelihood nonlinear feature transformation method for GMM-HMM speaker adaptation

We describe a novel maximum likelihood nonlinear feature bias compensation method for Gaussian mixture model-hidden Markov model (GMM-HMM) adaptation. Our approach exploits a single-hidden-layer neural network (SHLNN) that, similar to the extreme learning machine (ELM), uses randomly generated lower-layer weights and linear output units. Different from the conventional ELM, however, our approach optimizes the SHLNN parameters by maximizing the likelihood of observing the features given the speaker-independent GMM-HMM. We derive a novel and efficient learning algorithm for optimizing this criterion. We show, on a large vocabulary speech recognition task, that the proposed approach can cut the word error rate (WER) by 13% over the feature maximum likelihood linear regression (fMLLR) method with bias compensation, and can cut the WER by more than 5% over the fMLLR method with both bias and rotation transformations if applied on top of the fMLLR. Overall, it can reduce the WER by more than 27% over the speaker-independent system with 0.2 real-time adaptation time.
Impact of phase II trials with progression-free survival as end-points on survival-based phase III studies in patients with anaplastic gliomas

Background To assess progression-free survival (PFS) as the appropriate end-point for phase II trials for anaplastic gliomas (AGs) and to determine the impact of PFS on survival-based phase III trials.
Adapting a behavioral theory to measure diabetes-related dietary adherence

Patient adherence to therapeutic diets is essential for managing many chronic illnesses. Unfortunately, meal plan compliance has been notoriously difficult to measure. As a result, researchers have frequently been unable to scientifically and economically verify that patients have employed recommended nutrition plans at therapeutic levels. Moreover, traditional ad­ herence measures (e. g., diaries and recalls) have not generally allowed clinicians to diagnose causes of ad­ herence problems. This article describes our first steps toward developing reliable, valid, economical, and clinically meaningful measures of dietary adherence. First, we briefly present the theory underlying the general method. Then, we describe how we adapted the method to measuring dietary adherence. Finally, we present pilot study data that illustrate the use of the method.
Center of gravity dynamic stability in normal and vestibulopathic gait.

The purpose of this study was to examine the three-dimensional whole body center of gravity (CG) kinematics during free and paced gait in healthy subjects (n=16) and individuals with vestibulopathy (n=8). The cycle time, double and single stance phase durations, values and timing of CG forward velocity, and CG vertical displacement were recorded using an 11 segment, 66 degree of freedom whole body model. The free speed gait of the vestibulopathic individuals was remarkable for increased cycle time, increased percentage of time spent in the double stance phase, decreased forward velocity of the CG, and decreased vertical displacement of the CG. However, during paced gait, no statistically significant differences were found between the vestibulopathic and control groups in all measures. In all groups, CG horizontal velocity maxima and minima significantly lagged CG vertical minima and maxima respectively. We conclude that whole body CG control does not result purely from optimization of mechanical potential and kinetic energy exchanges: our temporal offsets in the maxima and minima of the CG horizontal velocity and vertical displacement make this mechanically impossible. Furthermore, individuals with vestibular impairment may self-select a slower walking speed to ease their biomechanic stability challenge despite being able to ambulate faster with 'normal' CG velocities and displacements. Copyright 1998 Elsevier Science B.V.
Zebrafish Gli3 functions as both an activator and a repressor in Hedgehog signaling

Hedgehog (Hh) signaling regulates cell differentiation and patterning in a wide variety of embryonic tissues. In vertebrates, at least three Gli transcription factors (Gli1, Gli2, and Gli3) are involved in Hh signal transduction. Comparative studies have revealed divergent requirements for Gli1 and Gli2 in zebrafish and mouse. Here, we address the question of whether Gli3 function has also diverged in zebrafish and analyze the regulatory interactions between Hh signaling and Gli activity. We find that zebrafish Gli3 has an early function as an activator of Hh target genes that overlaps with Gli1 activator function in the ventral neural tube. In vitro reporter analysis shows that Gli3 cooperates with Gli1 to activate transcription in the presence of high concentrations of Hh. During late somitogenesis stages, Gli3 is required as a repressor of the Hh response. Gli3 shares this repressor activity with Gli2 in the dorsal spinal cord, hindbrain, and midbrain, but not in the forebrain. Consistently, zebrafish Gli3 blocks Gli1-mediated activation of a reporter gene in the absence of Hh in vitro. In the eye, Gli3 is also required for proper ath5 expression and the differentiation of retinal ganglion cells (RGCs). These results reveal a conserved role for Gli3 in vertebrate development and uncover novel regional functions and regulatory interactions among gli genes.
Field evaluation of mutant and hybrid lines of mint for resistance to Verticillium wilt and yield

Abstract Mint lines that were previously identified with low wilt-severity values in the greenhouse were evaluated for resistance to Verticillium wilt and yield in the field in the presence of naturally occurring inoculum and in plots artificially infested with the soilborne fungus. Severity of Verticillium wilt varied significantly among mint lines and cultivars in the inoculated and non-inoculated sub-plots in two field trials. Verticillium wilt was significantly less severe for mutant lines 87M0109-1, 84M0107-7, and M90-11 than for Black Mitcham in 2002 and 2003. Verticillium wilt was significantly less severe for mutant line M83-14 and for Murray Mitcham than for Black Mitcham in 2003 and 2004. At the completion of the first trial, fresh hay yields of both peppermint hybrids 87M0109-1 and 84M0107-7 and peppermint mutant M90-11 were significantly higher than the standards Black Mitcham and Redefined Murray Mitcham. Oil yield in the first trial of standard Black Mitcham declined in years 3 and 4, while the decline in oil yield was less dramatic with the other four peppermint lines. In the second trial, hay yields of both B90-9 and M83-14 were comparable to, but not significantly different from Black Mitcham and Redefined Murray Mitcham. Line 92(B-37 × M0110)-1 yielded significantly less oil than all peppermint lines including both standards Black Mitcham and Redefined Murray Mitcham in six of the seven cuttings in the second trial. Verticillium rating of the lines and cultivars inoculated in trials from a previous greenhouse study were highly correlated with the Verticillium wilt rating of the lines and cultivars the second and third years when inoculated in both field nurseries in this study. Verticillium wilt resistance and yield can be improved in commercial mint cultivars and form a basis for managing the disease.
Center manifolds, normal forms and bifurcations of vector fields with application to coupling between periodic and steady motions ☆

Abstract We study the instabilities known to aeronautical engineers as flutter and divergence. Mathematically, these states correspond to bifurcations to limit cycles and multiple equilibrium points in a differential equation. Making use of the center manifold and normal form theorems, we concentrate on the situation in which flutter and divergence become coupled, and show that there are essentially two ways in which this is likely to occur. In the first case the system can be reduced to an essential model which takes the form of a single degree of freedom nonlinear oscillator. This system, which may be analyzed by conventional phase-plane techniques, captures all the qualitative features of the full system. We discuss the reduction and show how the nonlinear terms may be simplified and put into normal form. Invariant manifold theory and the normal form theorem play a major role in this work and this paper serves as an introduction to their application in mechanics. Repeating the approach in the second case, we show that the essential model is now three dimensional and that far more complex behavior is possible, including nonperiodic and ‘chaotic’ motions. Throughout, we take a two degree of freedom system as an example, but the general methods are applicable to multi- and even infinite degree of freedom problems.
How common is the most common adult movement disorder? Estimates of the prevalence of essential tremor throughout the world

Essential tremor (ET) is the most common adult movement disorder, as much as 20 times more prevalent than Parkinson's disease. Estimates of the crude prevalence of ET range widely from 0.08 to 220 cases per 1000 persons, a 2750-fold difference. There has been no formal attempt to synthesize these disparate results. Our purpose is to provide an overview of existing studies, to examine methodologic issues that may account for this tremendous variability in results, and to provide a more precise estimate of the prevalence of ET. Nineteen studies of the prevalence of ET were reviewed. Factors that contribute to the broad range of prevalence estimates include (a) differences in study design that influence validity and (b) differences in characteristics of study populations that influence comparability of studies. If we limit our examination to studies that (a) provided diagnostic criteria for ET, (b) defined ET as an action tremor, and (c) used community-based rather than service-based designs, then five studies remain, and the prevalence of ET is 4.1 to 39.2 cases per 1000, a 9.6-fold difference. Four of these five provided age-stratified data. Among these four, the prevalence of ET in those over the age of 60 years was 13.0 to 50.5 cases per 1000, a 3.9-fold difference.
Gastrointestinal pythiosis in Missouri dogs: eleven cases.

Pythium insidiosum is the cause of gastrointestinal and muscularis of the stomach, pylorus, and small intestine, with subcutaneous pythiosis of dogs. Pythium spp. are aquatrare involvement of the mesentery, mesenteric lymph nodes, ic oomycetes of the kingdom Protoctista found in tropical and pancreas. The pyogranulomas typically consisted of neand subtropical climates where high temperatures favor their crotic foci infiltrated and surrounded by neutrophils, eosingrowth. Canine gastrointestinal pythiosis, formerly included ophils, epithelioid macrophages, plasma cells, and multiamong the gastrointestinal phycomycoses, is characterized nucleated giant cells (Fig. 1). Etiologic agents were not apparent by severe granulomatous inflammation of the alimentary tract in HE-stained sections, although Splendore Hoeppli reacand associated tissues. Prevalence is highest among young tions surrounded clear spaces within the granulomas. Exmale dogs of large breeds, with case reports from the United amination of Grocott’s methenamine silver-stained sections States limited to states bordering the Gulf of Mexico. In revealed branching, rarely septate hyphae, 5-8 μm in dithis report, we describe 11 cases of gastrointestinal pythiosis, ameter with nearly parallel walls within the granulomas (Fig. confirmed by immunohistochemical techniques, in dogs from 2). A presumptive diagnosis of gastrointestinal pythiosis was the midwestem state of Missouri. based on histologic findings. Formalin-fixed tissue samples from 11 dogs with gastrointestinal pythiosis were received by the University of Missouri Veterinary Medical Diagnostic Laboratory from November 1987 through January 1991. Information regarding these dogs is contained in Table 1. The average age of the dogs was 2.5 years, 8 of 11 were female, and several large and small breeds were represented. Clinical histories were typified by chronic anorexia, weight loss, vomiting, and diarrhea. The tissue samples were collected during exploratory celiotomy or necropsy and were identified by the submittors as masses or neoplasms of the gastrointestinal tract or associated tissues. The diagnosis was confirmed by an indirect immunoperoxidase technique specific for Pythium as previously described. Rabbit serum containing primary antibody specific to Pythium antigen was applied to formalin-fixed tissue sections, which were subsequently stained using an avidin-biotin immunoperoxidase technique and examined microscopically. Negative controls with no primary antibody were run with all samples.
Modeling of polarization effects on n-GaN/i-InGaN/p-Gan solar cells with ultrathin GaN interlayers

We report the numerical study of n-GaN/i-InGaN/p-GaN solar cells on Ga-face substrates with thin GaN interlayers present in the intrinsic InGaN region. These interlayers have recently been shown to significantly increase the crystal quality of thick InGaN layers $$(>\!\!\!120\,\text{ nm})$$ . We find that tunneling is efficient in n-i-p structures having interlayers $$\le \! 1.5\,\text{ nm}$$ thick if polarization charges are sufficiently screened. If left unscreened, the large polarization charges naturally formed at the heterointerfaces degrades n-i-p performance, at a given interlayer thickness, because polarization charges increase the distance that carriers must tunnel. Simulations identify favorable parameter ranges.
Superconductivity in the (Dy1−xPrx) Ba2Cu2Oy system

Abstract A series of orthorhombic (Dy1−xPrx) Ba2Cu3Oy samples with x=0−1.0 were synthesized and characterized by XRD, DTA and electrical resistivity measurements. Pr-doping suppresses the superconducting transitions more or less linearly to a complete quenching at x⋍0.6. Meanwhile, increase in normal-state resistivities and their deviation from a linear temperature dependence begin to show up near x⋍0.3-0.4, beyond which a semiconducting behavior prevails. These results are discussed in conjunction with those previously reported for isomorphic compounds (Y1−xPrx)Ba2Cu3Oy, (Eu1−xPrx)Ba2Cu3 Oy, and (Gd in1−xPrx)Ba2Cu3Oy.
Otto Stern and the double bank shot

In analogy to a double surface scattering study of Estermann, Frisch and Stern for selecting and detecting the velocity of a beam of particles, it is proposed to use double surface scattering to investigate the collision dynamics of a beam of polarized particles with a known surface. In this proposed experiment, the first surface scattering event prepares a polarized (aligned/oriented) beam of particles, and the second surface scattering event permits the measurement of how the polarized beam interacts with the surface under study.
Interferon Inhibits Dengue Virus Infection by Preventing Translation of Viral RNA through a PKR-Independent Mechanism

Abstract Previously, we demonstrated that pretreatment of cells with interferon (IFN) α + γ or β + γ inhibited dengue virus (DV) replication. In this study, experiments were performed to better define the mechanism by which IFN blocks the accumulation of dengue virus (DV) RNA. Pretreatment of human hepatoma cells with IFN β + γ did not significantly alter virus attachment, viral entry, or nucleocapsid penetration into the cytoplasm. The inhibitory effect of IFN was retained even when naked DV RNA was transfected directly into cells, confirming that steps associated with viral entry were not the primary target of IFN action. Biosynthetic labeling experiments revealed that IFN abolished the translation of infectious viral RNA that occurred prior to RNA replication. Subcellular fractionation experiments demonstrated that IFN did not significantly alter the ability of viral RNA to attach to ribosomes. The antiviral effect of IFN appeared independent of the IFN-induced, double-stranded RNA-activated protein kinase (PKR) and RNase L, as genetically deficient PKR − RNase L − cells that were infected by DV retained sensitivity to inhibition by IFN. We conclude that IFN prevents DV infection by inhibiting translation of the infectious viral RNA through a novel, PKR-independent mechanism.
An instrumental variable method of estimation for disequilibrium markets in centrally planned economies

Abstract Estimating the canonical disequilibrium model is computationally difficult and sometimes impossible. This paper suggests a new model specification by noticing some peculiar institutional features in CPEs. Standard instrumental variable methods thus can be used. The estimators are asymptotically consistent and robust with respect to data errors. An example from the Chinese economy is given in the paper.
The evaluation of matrix elements in the analysis of anharmonic molecular vibrations: Functional taylor series expansions

This article presents methods for computing Cartesian Gaussian matrix elements using a Taylor series for general potential energy operators that admit well-behaved radial derivatives. These operators arise in the analyses of anharmonic vibrations in molecules. Application to the evaluation of matrix elements for hydrogen associated two wells illustrates the method. © 1995 John Wiley & Sons, Inc.
Advanced Concepts, Technologies and Flight Experiments for NASA's Earth Science Enterprise

Over the last 25 years, NASA Langley Research Center (LaRC) has established a tradition of excellence in scientific research and leading-edge system developments, which have contributed to improved scientific understanding of our Earth system. Specifically, LaRC advances knowledge of atmospheric processes to enable proactive climate prediction and, in that role, develops first-of-a-kind atmospheric sensing capabilities that permit a variety of new measurements to be made within a constrained enterprise budget. These advances are enabled by the timely development and infusion of new, state-of-the-art (SOA), active and passive instrument and sensor technologies. In addition, LaRC's center-of-excellence in structures and materials is being applied to the technological challenges of reducing measurement system size, mass, and cost through the development and use of space-durable materials; lightweight, multi-functional structures; and large deployable/inflatable structures. NASA Langley is engaged in advancing these technologies across the full range of readiness levels from concept, to components, to prototypes, to flight experiments, and on to actual science mission infusion. The purpose of this paper is to describe current activities and capabilities, recent achievements, and future plans of the integrated science, engineering, and technology team at Langley Research Center who are working to enable the future of NASA's Earth Science Enterprise.
Alternatives for assessing the presence of advanced intellectual abilities in young children

Intellectually gifted young children may demonstrate the emergence of advanced intellectual abilities during the preschool years, yet present screening instruments do not readily identify such abilities in these children. Changing conceptions of cognitive growth and intelligence from the field of cognitive and developmental psychology present alternatives for assessing young children's reasoning ability and strategy‐use when solving novel, unfamiliar problems. In this article, assessment procedures aimed at differentiating intellectually gifted young children from their nongifted peers are proposed as alternatives to traditional identification procedures.
Minimum principles for the thomas–fermi–dirac density

For an atomic or molecular system we consider the evaluation of the Thomas--Fermi--Dirac energy functional using an electron density whose value and bounding surfaces differ by small amounts from those of the exact Thomas--Fermi-- Dirac electron density. The resulting energy is shown necessarily to be higher than the true Thomas--Fermi--Dirac energy. If the displacement of the boundary is not small, the conclusion still holds as long as the boundary of the approximate density lies everywhere outside that of the exact density. (auth)
Automating analysis of qualitative preferences in goal-oriented requirements engineering

In goal-oriented requirements engineering, a goal model graphically represents relationships between the required goals (functional requirements), tasks (realizations of goals), and optional goals (non-functional properties) involved in designing a system. It may, however, be impossible to find a design that fulfills all required goals and all optional goals. In such cases, it is useful to find designs that provide the required functionality while satisfying the most preferred set of optional goals under the goal model's constraints. We present an approach that considers expressive qualitative preferences over optional goals, as these can model interacting and/or mutually exclusive subgoals. Our framework employs a model checking-based method for reasoning with qualitative preferences to identify the most preferred alternative(s). We evaluate our approach using existing goal models from the literature.
Immunochemical Studies of Infectious Mononucleosis

. A glycoprotein was isolated from the membrane of the bovine erythrocyte by refluxing the acetone- and ethanol-extracted stroma residue with 75% ethanol. The glycoprotein was purified by phosphocellulose chromatography, ethanol precipitation, lipid-solvent extraction and DEAE chromatography. The glycoprotein appeared to have two serological determinants, both reactive with antibodies present in the sera of patients with infectious mononucleosis. One of the determinants is similar to the Paul-Bunnell heterophile antigen found on sheep erythrocytes. It is dependent on carbohydrate, including sialic acid residues. Another specificity, seemingly not shared by sheep erythrocytes to any great extent, is resistance to neuraminidase and to alkaline borohydride treatment and thus it may be located either on the polypeptide portion of the molecule or on an alkali-stable oligosaccharide. The purified glycoprotein comprises 73% amino acids. Carbohydrate components and their molar ratios were sialic acid (1.0): galactose (1.5): N-acetylglucosamine (1.1): N-acetylgalactosamine (0.5): mannose (0.1).
KINETICS OF STRUCTURAL RELAXATIONS IN A TWO-DIMENSIONAL MODEL ATOMIC GLASS III

The kinetics of structural relaxation in a two-dimensional model atomic glass quenched infinitely rapidly from the melt to 0.55 of the glass transition temperature was simulated by the molecular dynamics methods to study the chronological ordering of the atomic kinematics associated with such relaxations. Over the very short periods of ageing (ca. 200 atomic fluctuations) accessible to the molecular dynamics (MD) method, a Williams-Watts form of relaxation with a fractional exponent of 0.5 was found to hold for excess enthalpy, free volume and site distortion parameter. The distribution of free energy barriers associated with the relaxation that resulted from the analysis could be scaled up to describe processes occurring on macroscopic timescales, and agrees well with experimental results in Cu$\_{x}$Zr$\_{1-x}$ glasses. Results on the clustering of relaxations and other topological features of the relaxation process are also reported.
Modality maps within primate somatosensory cortex

The sensations of pressure, flutter, and vibration are psychophysically distinct tactile modalities produced by frequency-specific vibrotactile stimulation of different mechanoreceptors in the skin. The information coded by the different low-threshold mechanoreceptors are carried by anatomically and electrophysiologically distinct pathways that remain separate at least up to and including the input stage of primary somatosensory cortex (SI) in primates, area 3b. Little is known about the functional organization of tactile representation beyond that stage. By using intrinsic optical imaging methods to record from area 1, the second processing stage of SI, we present evidence that pressure, flutter, and vibratory stimuli activate spatially distinct cortical domains in area 1, further strengthening the foundation for modality-specific processing streams in SI. These modality domains exhibit an organization that is unlike the discontinuous modality maps in visual area V2 but more like the continuous visual orientation maps in V1. The results demonstrate that psychophysically distinct sensory modalities can have fundamentally different modes of cortical representation.
Role of EUS and EUS-guided FNA in the diagnosis of symptomatic rectosigmoid endometriosis.

Background Rectosigmoid endometriosis is an underrecognized cause of GI symptoms in women. Pelvic magnetic resonance imaging and CT have a low sensitivity in making this diagnosis. The role of EUS and EUS-guided FNA (EUS-FNA) in the diagnosis of rectosigmoid endometriosis in symptomatic patients is not well studied. Methods A review of medical records identified 5 women who were diagnosed with rectosigmoid endometriosis by EUS and EUS-FNA over a period of 1 year. Observations Five women with nonspecific GI complaints underwent EUS examination of a rectosigmoid subepithelial mass found on colonoscopy. EUS revealed a hypoechoic lesion infiltrating the muscularis propria and the serosa of the rectal wall, and extending outside the rectal wall, findings consistent with rectosigmoid endometriosis. This diagnosis was confirmed by EUS-FNA, surgical exploration, and/or the patient's clinical course. Conclusions EUS and EUS-FNA are noninvasive, sensitive techniques for the diagnosis of rectosigmoid endometriosis in symptomatic patients.
The structure of Si(OOl) 2 × 1 surface — Studied by low energy electron diffraction

Abstract Intensity-voltage spectra of low energy electron diffraction are calculated by the quasidynamical method and the results analyzed to determine the validity of new structural models proposed for the Si(001) surface.
Stereoscopic X-ray angiography

There is a significant need for three-dimensional (3-D) spatial information in digital X-ray angiography (imaging of blood vessels). Availability of new, fast, c-arm systems, digital imagers and stereoscopic displays makes it possible to acquire stereoscopic X-ray angiograms. The authors develop a stereo-geometry model to explain acquisition geometry as well as basic aspects of stereoscopy, such as disparity, depth resolution and depth distortion. The authors also perform some simple experiments to verify the model. Finally, they present a set of guidelines for optimal stereoscopic acquisition.
Optimal Deployment for Magnetic Induction-Based Wireless Networks in Challenged Environments

New propagation techniques using magnetic induction (MI) waveguide solves the problems of traditional techniques in many challenged environments, such as underground, mines/tunnels, and oil reservoirs. However, deploying MI waveguides to connect the wireless nodes in such networks is challenging due to the high deployment cost, the complex shape of the communication range of the MI waveguides, and the significant impacts of the node failure and relay coil displacement. To date, the deployment problems in the MI-based networks have not been addressed. In this paper, the optimal MI waveguide deployment strategies are investigated in both one and two dimensional MI-based networks where the nodes are distributed either randomly or according to a regular lattice. Validated by both theoretical deduction and simulations, the proposed deployment strategies can construct a reliable MI-based network that is robust to node failure and relay coil displacement with minimum cost.
Numerical Solution for Perpendicular Sonic Hydrogen Injection into a Ducted Supersonic Airstream

This note discusses a computer program being developed to study the flow field near opposing perpendicular fuel injectors in scramjets. The MacCormack time-split, finite difference relaxation technique was used to solve the full two-dimensional compressible Navier-Stokes equations along with energy and species equations. By using this technique, a program was developed to consider the turbulent nonreacting flow of hydrogen and air in a rectangular duct. A damping term, proportional to the second derivative of pressure and temperature, was used to produce a stable solution behind the hydrogen jet in the neighborhood of the recompression shock. A case using actual conditions encountered in current scramjet design was analyzed, with results agreeing qualitatively with experimental observations.