cssi/SciSciGPT-SciSciNet huggingface dataset:
The Twitter Social Mobility Index: Measuring Social Distancing Practices With Geolocated Tweets.

BACKGROUND: Social distancing is an important component of the response to the COVID-19 pandemic. Minimizing social interactions and travel reduces the rate at which the infection spreads and "flattens the curve" so that the medical system is better equipped to treat infected individuals. However, it remains unclear how the public will respond to these policies as the pandemic continues. OBJECTIVE: The aim of this study is to present the Twitter Social Mobility Index, a measure of social distancing and travel derived from Twitter data. We used public geolocated Twitter data to measure how much users travel in a given week. METHODS: We collected 469,669,925 tweets geotagged in the United States from January 1, 2019, to April 27, 2020. We analyzed the aggregated mobility variance of a total of 3,768,959 Twitter users at the city and state level from the start of the COVID-19 pandemic. RESULTS: We found a large reduction (61.83%) in travel in the United States after the implementation of social distancing policies. However, the variance by state was high, ranging from 38.54% to 76.80%. The eight states that had not issued statewide social distancing orders as of the start of April ranked poorly in terms of travel reduction: Arkansas (45), Iowa (37), Nebraska (35), North Dakota (22), South Carolina (38), South Dakota (46), Oklahoma (50), Utah (14), and Wyoming (53). We are presenting our findings on the internet and will continue to update our analysis during the pandemic. CONCLUSIONS: We observed larger travel reductions in states that were early adopters of social distancing policies and smaller changes in states without such policies. The results were also consistent with those based on other mobility data to a certain extent. Therefore, geolocated tweets are an effective way to track social distancing practices using a public resource, and this tracking may be useful as part of ongoing pandemic response planning.
Cross‐sectional comparisons of gut microbiome and short‐chain fatty acid levels among children with varied weight classifications

BACKGROUND Limited studies associate changes in microbiota composition and metabolites among children and adolescents with obesity. Decreases in compositional diversity, increases in the proportion of Firmicutes and Bacteroidetes (F/B ratio) and increases in short-chain fatty acids (SCFAs) have been proposed as contributing factors in the pathophysiology of obesity. OBJECTIVES The aim of the current study was to characterize the faecal microbiota composition, diversity, F/B ratio and SCFA levels in different weight categories (lean, overweight, obesity classes 1-3) of children ages 5 to 12 years. METHODS We collected and processed 83 samples from different weight categories (27.7% lean, 11% overweight, 15%, 17% and 17% of obesity classes 1, 2, and 3, respectively). Microbiota content was determined by sequencing the V4 region of the 16S rRNA gene, and SCFA content was analyzed. RESULTS Microbiota compositions showed no significant differences in diversity or F/B ratios between weight categories. However, a relative abundance of Proteobacteria and lack of Verrucomicrobia were demonstrated when comparing severe obesity to the leaner groups. Faecal butyrate, propionate and isopentanoate concentrations increased progressively with weight category demonstrating significance in the class 3 obesity group. CONCLUSIONS Our results show that severe childhood obesity in our study population was associated with changes in gut microbiome composition correlated to previously reported cardiometabolic disease states in obesity. Increased SCFA levels correlate with obesity-related microbiome metabolic function without a reduction in diversity characterized at a phyla level. Further characterization of these specimens at a species level and longitudinal studies are needed to elucidate these relationships.
Safe Passage Through the Cross-Border Data Minefield

Companies, governments, and individuals are using data to create new global sectors that depend on information economies of scale and scope and the free flow of information across borders. These new sectors need clear rules and exceptions to the rules governing cross-border data flows. At the same time, people need to trust in these rules and believe that their personal data will be protected. The current approach to governing cross-border data flows through trade agreements has not led to binding universal nor interoperable rules. Language in trade agreements built on e-commerce-where there is a direct transaction, but this is not true for data driven sectors. Moreover, most trade agreements include a privacy or data-protection floor but do not include clear and universal personal data protection rules. Policymakers must devise a new approach to regulating trade in data because so much of this data is personal data. Given the import of the data-driven economy, people won’t trust it if they don’t gain greater control over their personal data. In this article, I propose a path through the data minefield. Such an approach would be built on giving people greater control over how their data is monetized and utilized. I also present a set of ideas about what any international agreement on data should include. A different path may also empower developing countries where citizens have lots of data to sell but are not yet able to create data-driven firms.
The Art of Voice Acting: The Craft and Business of Performing Voiceover, 6th Edition

Now in its sixth edition, James Alburger’s The Art of Voice Acting serves as an up-to-date, all-in-one manual for those interested in a career as a voiceover artist. Twenty years after its first ed...
Logic and Set Theory

Let me first state what the present chapter does not do. It is not intended to give an introduction to logic or set theory. As mentioned in the Preface, such an introduction is presupposed. Secondly, it is not meant to give to any satisfactory degree an overview of the basic results and techniques in logic (see for this Hodges, 1983).
Knowledge-based design of generate-and-patch problem solvers that solve global resource assignment problems

We present MENDER, a knowledge based system that implements software design techniques that are specialized to automatically compile generate-and-patch problem solvers that satisfy global resource assignments problems. We provide empirical evidence of the superior performance of generate-and-patch over generate-and-test: even with constrained generation, for a global constraint in the domain of '2D-floorplanning'. For a second constraint in '2D-floorplanning' we show that even when it is possible to incorporate the constraint into a constrained generator, a generate-and-patch problem solver may satisfy the constraint more rapidly. We also briefly summarize how an extended version of our system applies to a constraint in the domain of 'multiprocessor scheduling'.
The Case for a Bimodal Size Distribution in Titan’s Upper Haze Layer

Recent flybys of Titan have provided strong evidence that the upper haze layer, or layers, on Titan are both highly polarizing and forward scattering. Spherical particles tend to have either one quality or the other but not both. A search of prolate spheroids has been carried out and a class of particles defined in which large particles (x=3.4) can be highly polarizing. It is found that even these particles cannot explain the spacecraft measurements at large phase angles. A second nucleation mode of tiny aerosols is proposed which can provide the back scattering necessary to match the geometric albedo. Without this second size mode the particles must be so bright that the polarization is lost through multiple scattering.
Performance of meteor burst communication using variable data rates

The performance of a meteor-burst (MB) communication system is analyzed. The message to be transmitted consists of a number of packets, and the data rate is varied as a function of the channel state in order to maintain an approximately constant bit error rate (BER). The message is assumed to be repeated an indefinite number of times. The quantity of interest is the probability that the message will be received correctly at least once in a time span of T/sub D/ seconds. This analysis is a continuation of a previous analysis (S. Davidovici and E.G. Kanterakis, Performance of a Meteor-Burst Communication System Using Packet Messages with Variable Data Rates, IEEE Trans. Comm., to be published), where the message was assumed to be contained in a single packet. It is shown that considerable improvement can be gained when the message is contained in many packets as opposed to the case when the message consists of a single packet. >
Bladder management after spinal cord injury in the United States 1972 to 2005.

Purpose: Studies have shown that bladder management with an indwelling catheter for patients with spinal cord injury is associated with more urological complications such as stones, urinary infection, urethral strictures and bladder cancer. However, little is known about actual bladder management for these patients in clinical practice.Materials and Methods: Using the National Spinal Cord Injury Database the bladder management method was determined at discharge from rehabilitation and at each 5-year followup period for 30 years.Results: At discharge from rehabilitation (24,762 patients) the selection of bladder management with a condom catheter decreased steadily from a peak of 34.6% in 1972 to a low of 1.50% in 2001. The use of clean intermittent catheterization increased from 12.6% in 1972 to a peak of 56.2% in 1991. Indwelling catheter use initially decreased from 33.1% in 1972 to 16.5% in 1991 but increased to 23.1% in 2001. Of 12,984 individuals with followup data those originally using an indwelling...
Phage DNA Dynamics in Correlation with Cell Fates

Bacteriophage lambda begins its infection cycle by ejecting its DNA into its host E. coli cell, after which either the lytic or lysogenic pathway is chosen, resulting in different cell fates. In this study, using a new technique to monitor the spatiotemporal dynamics of the phage DNA in vivo, we found that the phage DNA moves via two distinct modes: localized motion and motion spanning the whole cell. One or the other motion is preferred depending on where the phage DNA is ejected into the cell. Through the phage DNA trajectories, we quantified the diffusion coefficient. Moreover, phage DNA motion is the same in the early phase of the infection cycle, irrespective of whether the lytic or lysogenic pathway is followed; hence, cell-fate decision-making appears not to be correlated with the phage DNA motion. However, after the cell commits to one pathway or the other, phage DNA movement slows during the late phase of the lytic cycle and remains the same during the entire lysogenic cycle. Throughout the infection cycle, phage DNA prefers the regions around the quarter positions of the cell.
The size of government

Most research on the causes of growth in government expenditure has focused on the demand for government services. In this paper, we argue that in fact this growth may have occurred because of changes in supply. Changes in technology leading to increased specialization and thus increased opportunity costs of self-production have led to increased market production and increased record keeping. Also, female labor force participation has increased. Both of these factors serve to reduce the (efficiency) cost of collecting taxes; if the demand for government spending has not changed, this increase in supply would lead to a larger public sector. We estimate a system of simultaneous equations for the period 1929–1970 incorporating this hypothesis, and the results are consistent with the theory. We are able to explain virtually all of the growth of government; increases in female labor force participation seems to be a very important variable in this explanation.
“Occult” post-contrast signal enhancement in pediatric diffuse intrinsic pontine glioma is the MRI marker of angiogenesis?

Introduction In diffuse intrinsic pontine gliomas (DIPG), subtracting pre-contrast from post-contrast T1-weighted images (T1WI) occasionally reveals subtle, “occult” enhancement. We hypothesized that this represents intravascular enhancement related to angiogenesis and hence that these tumors should have greater blood volume fractions than do non-enhancing tumors.
Synthesis, characterization and property study of new coordination polymers constructed from flexible dicarboxylates and bidentate nitrogen mixed ligands

Five new coordination polymers, [Cd(1,2'-cy) 0.5 (bix)H 2 O] n (1), [Cd 2 (1,2'-cy) 2 (1,10'-phen) 2 (H 2 O) 2 ] (2), {[Co(1,2-cy)(2,2'-bipy)(H 2 O) 2 ].2H 2 O} n . (3) {[Cd(succ)(1,10'-phen)H 2 O]·H 2 O} n (4), and {[Cd(succ)(2,2'-bipy)H 2 O]·2H 2 O} n (5) (1,2-cy=4-cyclohexene-1,2-dicarboxylate, succ = succinic acid, bix=1,4-bis(imidazol-1-ylmethyl)benzene, 1,10'-phen = 1,10-phenanthroline, 2,2'-bipy = 2,2'-bipyridine), have been synthesized and characterized by single-crystallographic X-ray diffraction. Complex 1 shows a two-dimensional covalent layer structure. Complex 2 exhibits a two-dimensional supramolecular layer network composed from discrete fundamental units. Complex 3 exhibits a one-dimensional covalent chain-like structure, which further extends to a two-dimensional supramolecular structure with hydrogen bonding and π-π interactions respectively. Complexes 4 and 5 show three-dimensional supramolecular networks composed from one-dimensional chain-like covalent structures. Furthermore, the magnetic property of complex 3 and fluorescent properties of complexes 1, 2, 4 and 5 have also been studied.
Experiments on Transition Regime Flow through a Short Tube with a Bellmouth Entry

Experiments were conducted to determine the mass flow rate and longitudinal pressure distribution along a short tube with a bellmouth entry for conditions ranging from free molecule to continuum. The tube has an inside diameter of 0.452 in., and the radius of the bellmouth entry is 0.75 in. The ratio of upstream stagnation pressure to downstream stagnation pressure was varied from 1.5 to more than 100. As the conditions departed from continuum toward free molecule, the effect of over all pressure ratio became quite pronounced until at free molecule conditions the effect was that predicted by Clausing. The transition could be seen in the pressure distribution (relatively flat under continuum conditions and linear between the two reservoir pressures under free molecule conditions) and in the mass flow (the discharge coefficient decreases rapidly until it reaches a constant under free molecule conditions). The Reynolds numbers of the tests ranged from 0.1 to 1500 and the pressures from 10 IJL to 10 mm. Nitrogen at 300°Kwas the test gas. Nomenclature A = cross-sectional area of tube CD = discharge coefficient D = diameter of tube m = mass flow P = pressure Q • =F a quantity related to mass flow being a product of pressure and volumetric flow rate Qc = value of Q according to the theory of Clausing Rex = Reynolds number based on length RBD ~ Reynolds number based on diameter T = temperature U = gas velocity X — longitudinal distance from beginning of constant area tube X = mean free path length v = kinematic viscosity p = density X = dynamic viscosity; also used as an abbreviation for microns of mercury
Range and multiple-scattering measurements of low-energy muons

Abstract We have simultaneously measured the range and multiple scattering of muons of kinetic energies between 9 and 25 MeV from foils of steel, aluminum, and polyethylene. We have expressed, after Moliere, the root-mean-square projected angle as: ϴ rms proj = A(L L rad ) 1 2 15(pv)−1 where L is the foil thickness, L rad the foil radiation length, p the muon momentum in MeV/ c , and v the muon velocity in units of c . We find that in this energy range A = 1.09 ± 0.02.
Phenylalanine 48 of Chromatium vinosum high potential iron protein is essential for stability of the oxidized [Fe4S4] cluster. Site-directed mutagenesis and NMR studies as a probe of cluster chemistry

Point mutations of the conserved aromatic residue phenylalanide 48 (Phe48Arg.His) in Chromatium vinosum high potential iron protein have been examined with the aim of understanding the functional role of this residue. For both mutants the change in midpoint potential of the [Fe4S4]3+/2+ cluster is minimal (< + 20 mV). The oxidized state is unstable relative to the recombinant native, with the observation of an ‘autoreduction’ pathway that appears to be mediated by degradation of the cluster in a fraction of the oxidized sample. This provides the reducing equivalents required to bring about reduction of the remainder of the sample. This degradative reaction results from the increased solvent accessibility of the cluster core in the non-conservative Phe48 mutants. Increased solvent access has been characterized by 1H15N HMQC experiments.
In Vitro Activities of a New Des-Fluoroquinolone, BMS 284756, and Seven Other Antimicrobial Agents against 151 Isolates of Eikenella corrodens

The des-fluoroquinolone BMS 284756 was active in vitro against all 151 clinical strains of Eikenella corrodens at a MIC of or = 4 microg/ml, including for two beta-lactamase-producing isolates. Amoxicillin-clavulanate and ampicillin-sulbactam inhibited all strains at a MIC of < or = 1 microg/ml.
Molecular analyses of carbonic anhydrase-II expression and regulation in the developing chicken lens

The expression of carbonic anhydrase-II (CA-II) in the developing chicken lens was examined and compared with that in the retina of the chicken embryo. CA-II expression was measured by immunohistochemistry and radioimmunoassay during development, and CA-II mRNA was quantified by Northern blot and densitometric scanning and localized by in situ hybridization. A functional promoter of the chicken CA-II gene was identified by transfection of primary embryonic chicken lens epithelial cells and analyzed in deletion mutants. The results establish that CA-II makes up about 0.1% of the total soluble protein of the embryonic chicken lens, an amount insufficient to make it a candidate for an enzyme crystallin in this species. Lens fiber differentiation coincided with a loss of CA-II mRNA and protein; by contrast, CA-II persisted in the epithelial cells of the embryonic and mature lens. This and previous studies showed that CA-II amounts to as much as 3% of the protein of the embryonic chicken retina and follows a different developmental time course of expression; like the lens, CA-II decreases until day 10 in the embryonic retina, but, unlike the lens, it increases thereafter and plateaus at hatching. Progressive deletions of the 5' flanking regions (from position -1314 to +32) of the CA-II gene fused to the bacterial chloramphenicol acetyltransferase (CAT) reporter gene resulted in a gradual loss of promoter activity, consistent with an additive effect of putative cis-regulatory elements found in many crystallin genes. These experiments provide the foundation for a molecular analysis of the developmental and differential regulation of the CA-II gene in lens and retina.
The serological detection of leukemia-associated antigens in chronic leukemia: correlation with disease status.

Changes in the expression of leukemia-associated antigens (LAA) on the peripheral blood cells of patients with chronic lymphocytic leukemia (CLL) and chronic myelogenous leukemia (CML) were monitored over a period of several months with a battery of heterologous antisera in a complement-dependent microcytotoxicity test system. The sera were prepared by immunization of rabbits and monkeys with human CLL, CML, or acute lymphoblastic, myeloblastic, or myelomonocytic leukemic cells, or cell extracts. Following extensive adsorption with normal human erythrocytes and leukocytes, these sera did not exhibit reactivity with peripheral blood monuclear cells, nor, in most cases, with enriched B-lymphocyte preparations from healthy donors. Cells from CLL patients reacted mainly with adsorbed antisera raised against lymphocytic leukemic cells, but there was significant cross-reactivity with antisera raised against myelomonocytic leukemia cells; the number and intensity of positive reactions correlated with leukemic cell counts. Cells from patients in the chronic stage of CML reacted almost exclusively with adsorbed antisera to myeloid leukemic cells. However, blastic transformation of CML was regularly accompanied and on one occasion preceded by the appearance of reactivity with antisera to lymphocytic leukemic cells. During remission, peripheral blood cells from most CML patients were LAA-negative; positive serologic reactions were often followed by major hematologic and clinical deterioration within a few months. These observations suggest that serological monitoring of LAA may represent a useful adjunct to present methods of evaluating the course and prognosis of chronic leukemias. Serological reactions may also have some utility in the differential diagnosis of leukemia.
An Observational Method in the Foreign Language Classroom: A Closer Look at Interaction Analysis

ABSTRACT Many classroom observation systems have been developed, including Flanders' interaction analysis. This system provides feedback to teachers about ten teacher-student verbal behavior categories. Data collected by observers are entered into a matrix which reveals ratios of the categories. Moskowitz's modification of interaction analysis (Foreign Language Interaction or Flint) expands Flanders to twenty-two categories. Both systems are deficient in accuracy, reliability, and practicality. Many be- havior categories are open to multiple interpretations. The number of categories observed, the rapid decisions made about frequently changing behaviors, and the necessity of recording data while verifying the passage of time make the observers' tasks difficult. The manner in which the data reliability is obtained is questionable. Researchers neglect instance by instance interactions; rather, by using Scott's coefficient, only summary data are considered. The time required to master these systems, the complexities of the category ratios and matrices, and the personal biases of teachers who observe themselves are all issues of practical concern. Further, there are serious methodological weaknesses in the research done thus far to evaluate these systems. Practitioners of interaction analysis and FLint must recognize the various problems of these methods before using them in research and training programs.
Electrospun collagen and its applications in regenerative medicine

In recent years, electrospinning has increased in popularity as a processing technique for obtaining nanometer-to-micron diameter polymer fibers collected to form a nonwoven scaffold. It possesses the ability to process collagen into nanofibrous scaffolds which have been used for a number of applications, such as artificial vascular grafts and for wound repair. This paper offers a review of some of the basic yet essential aspects of producing nanofibrous scaffolds of collagen by electrospinning. A primer to collagen structure, cross-linking techniques, and electrospinning principles is provided, along with some of the many applications of these unique materials.
Importance of motion in motion-compensated temporal discrete wavelet transforms

Discrete wavelet transforms (DWTs) applied temporally under motion compensation (MC) have recently become a very powerful tool in video compression, especially when implemented through lifting. A recent theoretical analysis has established conditions for perfect reconstruction in the case of transversal MC-DWT, and also for the equivalence of lifted and transversal implementations of MC-DWT. For Haar MC-DWT these conditions state that motion must be invertible, while for higher-order transforms they state that motion composition must be a well-defined operator. Since many popular motion models do not obey these properties, thus inducing errors (prior to compression), it is important to understand what is the impact of motion non-invertibility or quasi-invertibility on the performance of video compression. In this paper, we present new experimental results of a study aiming at a quantitative evaluation of such impact in case of block-based motion. We propose a new metric to measure the degree with which two motion fields are not inverses of each other. Using this metric we investigate several motion inversion schemes, from simple temporal sample-and-hold, through spatial nearest-neighbor, to advanced spline-based inversion, and we compare compression performance of each method to that of independently-estimated forward and backward motion fields. We observe that compression performance monotonically improves with the reduction of the proposed motion inversion error, up to 1-1.5dB for the advanced spline-based inversion. We also generalize the problem of "unconnected" pixels by extending it to both update and prediction steps, as opposed to the update step only used in conventional methods. Initial tests show favorable results compared to previously reported techniques.
The type of a torsion free finite loop space

Abstract In this paper we prove the following theorems: Theorem 1. If X is a two-torsion free finite loop space whose type consists of integers that are divisible by 4 and are less than 60, then X is of Lie type. Theorem 2. If X is a two-torsion free finite loop space whose type consists of integers that are divisible by 4 and for which the numbers of 43-dimensional and 51-dimensional generators of H∗(X;Q) are greater than or equal to the numbers of 47-dimensional and 55-dimensional generators, respectively, then X is of Lie type.
An autonomously replicating eukaryotic expression vector with a tetracycline-responsive promoter

Abstract The control elements of the tetracycline-resistance operon encoded in Tn 10 of Escherichia coli have previously been utilized by Gossen and Bujard [Proc. Natl. Acad. Sci. 89 (1992) 5547–;5551] to establish an efficient transcription regulatory system in mammalian cells. We describe here a modification of this vector system that encodes all required elements, including a neomycin-resistance gene, on an autonomously replicating episome. This, thereby, allows for improved transfection frequency and episome stability, providing an easily selectable marker gene and a promoter whose activity can be easily modulated to control gene expression.
Negligible subsets in the space of homeomorphisms

Abstract We show that for various compact metric spaces X , the space of homeomorphisms H ( X ) is homeomorphic to H ( X )⧹ K , where K =⋃ i >0 K i ⊂ H ( X ) where either (1) each K i is closed and equi-uniformly continuous or (2) each K i is complete in the metric of uniform convergence.
The agentsheets behavior exchange: supporting social behavior processing

In end-user programming it is still hard to overcome the tension between usability and expressiveness. Some end-user programming approaches focus on simple use but they make it hard or even impossible to write programs expressing useful functionality. Other programming approaches can be very expressive by allowing the construction of arbitrary complex programs but this expressiveness comes at the price of usability. End user programming approaches that are at least reasonably usable and expressive at the same time require not merely a syntactic improvement of programming languages but a new way to conceptualize the programming process in a social context. Social behavior processing describes the idea of elevating programming components to the level of easily composable and decomposable entities that can be shared through the World Wide Web with a community of end-users. The Agentsheets Behavior Exchange is outlined here as a forum for end-user programmers, including middle school kids and professionals, to (a) compose behaviors in order to create interactive SimCity™-like simulations and games, to (b) comprehend behaviors created by other users or by themselves, and to (c) share these behaviors with other users.
The Del Rio ataxite, Texas

Basic data are presented on the Del Rio, Nordheim, and Monahans ataxites found in Texas. Results are reported for bulk-chemistry analysis, metallographic observations, and electron-microprobe analysis of the Del Rio meteorite. It is shown that Del Rio is distinctly different from the other two ataxites in terms of nickel, phosphorous, and carbon content, and is composed of at least three coarse grains in different crystallographic orientations. All the kamacite in Del Rio is found to have transformation structures that are probable shock products, and minor inclusions of daubreelite, schreibersite, and troilite are observed. It is concluded that Del Rio was apparently mildly shocked prior to its fall.
The Boston residential nitrogen dioxide characterization study: classification and prediction of indoor NO2 exposure.

ABSTRACT Many epidemiological studies have used house characteristics associated with indoor sources as simplified proxies for personal nitrogen dioxide (NO2) exposure. Stove type and presence of a pilot light have often been used as the two key characteristics, but significant overlaps have remained in the NO2 concentrations in the exposed and unexposed groups. This has contributed to inconsistencies in epidemiological findings, due to potential misclassification of exposure. In this study, other possible proxies were analyzed by cross-table analyses and were investigated in terms of improvements in both classification and predictive power. Adding building type to the above two proxies resulted in 0–5% of households with concentrations overlapping the observed range for the opposing stratum, compared with 22–42% for the two-proxy model. In spite of this performance, the predictive power of regression models for indoor NO2 was not improved by the addition of the third proxy, and the potential sample popul...
A numerical method for predicting hypersonic flowfields

The flow about a body traveling at hypersonic speed is energetic enough to cause the atmospheric gases to chemically react and reach states in thermal nonequilibrium. The prediction of hypersonic flowfields requires a numerical method capable of solving the conservation equations of fluid flow, the chemical rate equations for specie formation and dissociation, and the transfer of energy relations between translational and vibrational temperature states. Because the number of equations to be solved is large, the numerical method should also be as efficient as possible. The proposed paper presents a fully implicit method that fully couples the solution of the fluid flow equations with the gas physics and chemistry relations. The method flux splits the inviscid flow terms, central differences of the viscous terms, preserves element conservation in the strong chemistry source terms, and solves the resulting block matrix equation by Gauss Seidel line relaxation.
Nonalcoholic fatty liver disease and bariatric surgery in adolescents

Obesity is a multi-organ system disease with underlying insulin resistance and systemic chronic inflammation. Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of the underlying metabolic dysfunction. This review provides a highlight of the current understanding of NAFLD pathogenesis and disease characteristics, with updates on the challenges of NAFLD management in obese and severely obese (SO) patients and recommendations for the pediatric surgeons' role in the care of SO adolescents.
Osmotic Demyelination Syndrome as a Consequence of Treating Hyperammonemia in a Patient With Ornithine Transcarbamylase Deficiency

A 7-year-old female patient with a new diagnosis of ornithine transcarbamylase deficiency was treated for hyperammonemia with a standard protocol. Several days later, she developed ataxia, dysmetria, and dysarthria. Magnetic resonance imaging of the brain demonstrated pontine and extrapontine white matter changes consistent with osmotic demyelination. Classically described as a consequence of hyponatremia treatment, osmotic demyelination syndrome has rarely been associated with other entities. This case suggests a potentially serious complication of the standard therapy for hyperammonemia in patients with ornithine transcarbamylase deficiency.
On the Oxygen Affinity of Bird Blood

In oxygen affinity characteristics bird blood appears to have several features that distinguish it from mammalian blood. For domesticated species at least the range of oxygen half saturation values is extremely wide. A difference in the shape of the oxygen dissociation curve has been recorded by several authors with an increase in sigmoidocity with increasing oxygen saturation. There is evidence that the oxygen affinity determining organic phosphate of bird red blood cells inositol pentaphosphate (IP5) is relatively metabolically inert. This suggests that modulation of blood oxygen affinity is primarily achieved by altering the IP5 hemoglobin interaction rather than varying IP5 levels per se . In contrast to mammals carbon dioxide has no direct effect on whole blood oxygen affinity for some bird species (hen chick goose) or it may cause the oxygen affinity to increase (pigeon flamingo). Carbon dioxide is a blood oxygen affinity modulator of some flexibility its effect in both direction and magnitude being dependent on the hemoglobin type red cell pH and organic phosphate levels. The physiological significance of these distinguishing features is discussed.
Mitochondrial DNA variation among worldwide populations of gypsy moths, Lymantria dispar.

Gypsy moth populations from Japan, mainland Asia, Europe, Tunisia, and North America were analyzed for variation in mitochondrial DNA (mtDNA) sequences from three gene regions. These samples resolve into four groups, representing gypsy moths from (1) Okinawa, Japan, (2) Hokkaido, Japan, (3) Honshu and Kyushu, Japan and mainland Asia, and (4) Europe, Tunisia, and North America. Some patterns of geographic variation observed for mtDNA (for example, the distinctiveness of gypsy moths from Hokkaido, Japan) coincide with those observed by Goldschmidt from analyses of morphology, life history, and intersexuality. Other patterns (relative sequence homogeneity across Asia, Honshu, and Kyushu and reduced levels of variation in mainland Japan) do not.
Displacement chromatography of biomolecules.

Displacement chromatography was used for the preparative-scale separation of peptides, antibiotics, and proteins. The feed components were both purified and concentrated during the separation processes. The components of a peptide mixture were separated on a reversed-phase analytical column using 2-(2-butoxyethoxy) ethanol as the displacer. The use of organic modifiers in the carrier along with an elevated column temperature of 45°C enabled the efficient separation of relatively hydrophobic peptides by displacement chromatography. In addition, the throughput of the process was significantly increased by carrying out the separation at an elevated flow-rate with no adverse effect on product purity. The antibiotic cephalosporin C was isolated from impurities in a fermentation broth using 2-(2-butoxyethoxy)ethanol as the displacer along with a step change in column temperature. The proteins cyctochrome c and lysozyme were purified on a weak cation-exchanger column using cationic polymers as the displacers. While polymers of 60 and 20 kilodaltons were both found to be good displacers for these proteins, only the lower molecular weight polymer was readily removed from the column by standard regeneration techniques.
Marginal Regression Models for Clustered Ordinal Measurements

Abstract This article constructs statistical models for clustered ordinal measurements. We specify two regression models: one for the marginal means and one for the marginal pairwise global odds ratios. Of particular interest are problems in which the odds ratio regression is a focus. Simple assumptions about higher-order conditional moments give a quadratic exponential likelihood function with second-order estimating equations (GEE2) as score equations. But computational difficulty can arise for large clusters when both the mean response and the association between measures is of interest. First, we present GEE1 as an alternative estimation strategy. Second, we extend to repeated ordinal measurements the method developed by Carey et al. for binary observations that is based on alternating logistic regressions (ALR) for the marginal mean parameters and the pairwise log-odds ratio parameters. We study the efficiency of GEE1 and ALR relative to full maximum likelihood. We demonstrate the utility of our regr...
Simulating hydrogen-bond clustering and phase behaviour of imidazole oligomers

We have modelled structures and dynamics of hydrogen bond networks that form from imidazoles tethered to oligomeric aliphatic backbones in crystalline and glassy phases. We have studied the behaviour of oligomers containing 5 or 10 imidazole groups. These systems have been simulated over the range 100–900 K with constant-pressure molecular dynamics using the AMBER 94 forcefield, which was found to show good agreement with ab initio calculations on hydrogen bond strengths and imidazole rotational barriers. Hypothetical crystalline solids formed from packed 5-mers and 10-mers melt above 600 K, then form glassy solids upon cooling. Viewing hydrogen bond networks as clusters, we gathered statistics on cluster sizes and percolating pathways as a function of temperature, for comparison with the same quantities extracted from neat imidazole liquid. We have found that, at a given temperature, the glass composed of imidazole 5-mers shows the same hydrogen bond mean cluster size as that from the 10-mer glass, and t...
Juvenile Myelomonocytic Leukemia in a 16-Year-Old With Noonan Syndrome: Case Report

A 16-year-old man with splenomegaly presented with ascites and bilateral leg eschars. Although he had intermittently elevated absolute monocyte counts, a diagnosis of juvenile myelomonocytic leukemia (JMML) was discounted because of his age and lack of persistent leukocytosis. Detailed examination demonstrated features consistent with Noonan syndrome (NS), including typical facies, growth retardation, a cardiac defect, and a history of a coagulopathy. He underwent a splenectomy where the surgeons encountered a rind of tissue composed of monocytes encasing the abdominal organs. After splenectomy, his leukocytes rose to over 100×10(9)/L with a monocytosis, suggesting JMML. On the basis of the clinical suspicion of NS, mutation analysis revealed a KRAS mutation, which is known to be common to both NS and JMML. Clinicians should have high index of suspicion for JMML in patients with Noonan features, regardless of a patient's age.
Metacognitive executive function training for young children with ADHD: a proof-of-concept study.

Executive functions (EF) are impaired in children with attention-deficit/hyperactivity disorder (ADHD). It may be especially critical for interventions to target EF in early childhood given the developmental progression of EF deficits that may contribute to later functional impairments. This proof-of-concept study examined the initial efficacy of an intervention program on EF and ADHD. We also examined child performance on three neurocognitive tasks assessing cognitive flexibility, auditory/visual attention, and sustained/selective attention. Children with ADHD (ages 3–7) and their parents were randomized to receive an intervention targeting metacognitive EF deficits (n = 13) or to a waitlist control condition (n = 12). Linear model analysis of covariance compared groups on parent EF ratings, blinded clinician ratings of ADHD symptoms and improvement, and child performance on neurocognitive measures. Children who received the intervention significantly improved on parent ratings of attention shifting and emotion regulation in addition to clinician ratings of inattention. Moderate effect sizes showed additional intervention effects on parent ratings of inhibition, memory, and planning, and clinician ratings of hyperactivity/impulsivity and overall improvement. Small effect sizes were observed for improvement on child neurocognitive measures. Although replication with a larger sample and an active control group is needed, EF training with a metacognitive focus is a potentially promising intervention for young children with ADHD.
Sodium-activated cation channels in peptidergic nerve terminals.

Abstract The patch-clamp technique was utilized to characterized a cation channel in peptidergic nerve terminals isolated from a crustacean neurosecretory system. The cation channel exhibits the unique property of being activated by [Na+]. Distributions of open times demonstrate the presence of two open states with a shift of the distribution from predominantly short times at [N+] ⩽ 10 mM to a predominantly long open state at [N+]⩾ 40 mM. Desensitization of channel activation occurs on prolonged exposure to [Na+] > 40 mM. Open probability increased steeply with [Na+] but was largely independent of membrane potential. Comparison of current-voltage relationships from single dissociated terminals and from those in situ in the intact system show no differences in conductance or selectivity with nearly equal permeability to Na+ and K+, and impermeability to Cs+, divalent cations and anions. Flickering block occured with [Ca2+]i > 1 μM. We propose that Na-activated cation (NAC) channels are activated by Na+ entering during action potentials and provide a sustained depolarizing current that can help sustain repetitive or bursting activity and subsequent facilitation of secretion from these nerve terminals.
10 -7 contrast ratio at 4.5λ/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks

We present here new experimental results on high contrast imaging of 10-7 at 4.lambda/D (lambda=0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5lambda/D diameter and a multi-Gaussian pupil plane mask. Both the masks were fabricated on very high surface quality (lambda/30) BK7 optical substrates using nano-fabrication techniques of photolithography and metal lift-off. This process ensured that the shaped masks have a useable edge roughness better than lambda/4 (rms error better than 0.2 microns), a specification that is necessary to realize the predicted theoretical limits of any mask design. Though a theoretical model predicts a contrast level of 10-12, the background noise of the observed images was speckle dominated which reduced the contrast level to 4x10-7 at 4.5lambda/D. The optical setup was built on the University of Illinois Seeing Improvement System (UnISIS) optics table which is at the Coude focus of the 2.5-m telescope of the Mt. Wilson Observatory. We used a 0.820 micron laser source coupled with a 5 micron single-mode fiber to simulate an artificial star on the optical test bench of UnISIS.
6I-4 Integrated Micromechanical Circuits Fueled By Vibrating RF MEMS Technology (Invited)

Having now produced devices with sufficient Q, thermal stability, aging stability, and manufacturability, vibrating RF MEMS technology is already finding its way into next generation timing and wireless applications. At this juncture, the technology is now poised to take its next logical steps: higher levels of circuit complexity and integration. In particular, as vibrating RF MEMS devices are perceived more as circuit building blocks than as stand-alone devices, and as the frequency processing circuits they enable become larger and more complex, the makings of an integrated micromechanical circuit technology begin to take shape, perhaps with a functional breadth to rival that of integrated transistor circuits. After briefly reviewing the present state of vibrating RF MEMS device technology, this paper suggests the mechanical circuit element attributes most likely to insure a broad functional range for future integrated micromechanical circuits
Advances in compressor technology (as reported in 1988)

Abstract An annotated review of the recent litterature on compressor technology is presented, covering primarily the 1988 Purdue compressor conference. A review of a few other papers is included. Comments are presented about common positive displacement refrigerant compressors, i.e. reciprocating, rolling piston and other rotary compressors, screw and scroll compressors. Comments are also made concerning several engineering technologies related to these compressors, i.e. vibrations and acoustics, gas pulsations, capacity control and efficiency, performance valve technology, bearings, oil and lubrication.
SPATIAL METAPHOR AND THE POLITICS OF EMPOWERMENT: MAPPING A PLACE FOR FEMINISM AND POSTMODERNISM IN GEOGRAPHY?*

Spatial language and constructs are deployed systematically in the writing of many contemporary feminists. Disempowerment is couched in negative spatial terms: as “displacement,” having space denied, or as a negative or non-space. Empowerment, on the other hand, is written as an appropriation of the spatial: creating new spaces, occupying existing spaces, or revalorizing negatively labeled spaces. Furthermore, the map emerges as a common trope in this writing. Rather than transparently communicating the totality of what exists, however, their maps become rhetorical guides to possible worlds. The spatial provides a textual tool with which many contemporary feminists contest existing power relations. Space is viewed as liberating, empowering, and political. Their use of the spatial contrasts with the apolitical (and, not inconsequentially, gendered) conceptualization of space in some postmodern writing. This divergent deployment of spatial textual devices in the writing of some contemporary feminists and that of some postmodernists opens up another window on the knotty nexus of feminist and postmodern thought in geography.
The effect of LH/FSH, dibutyryl cyclic AMP, and prostaglandins on the production of estrogens by rabbit granulosa cells in vitro.

The purpose of this study was to establish the effects of trophic hormones on the production of estrogens by rabbit granulosa cells. A pure population of these cells was isolated frompreovulatory follicles (1–1.5 mm in diameter) of estrous rabbits, and cultured for 6 days with either one or a combination of the following hormones: androstenedione, Pergonal (LH/FSH), dibutyryl cyclic AMP (Bu2cAMP), prostaglandin F2α (PGF2α, or prostaglandin E2 (PGE2). The medium was collected every 2 days and progesterone(P), estrone (E1) and estradiol–17β (E2α) were measured by radioimmunoassay. Granulosa cells cultured as controls (i.e., without exogenous trophic hormones) secreted P spontaneously and its secretion was stimulated 100 to 1,000 fold with LH/FSH and Bu2cAMP, but not withPGF2α or PGE2. Androstenedione, either alone or with trophic hormones had no apparent effect on the cytology of the granulosa cells or their ability to secrete P. In the absence of exogenous androstenedione, the cultures produced very small ...
Maximum Likelihood Estimates for a Multivariate Normal Distribution when Some Observations are Missing

S EVERAL authors recently have derived maximum likelihood estimates of parameters of multivariate normal distributions in cases where some observations are missing (Edgett [2] and Lord [3], [4]). The purpose of this note is to give an approach to these problems that indicates the estimates with a minimum of mathematical manipulation; this approach can easily be applied to other cases. (The technique bears some resemblance to that of Cochran and Bliss in a dierent problem [1].) The method will be indicated by treating the simplest case involving a bivariate normal distribution. Suppose x and y have a bivariate normal distribution with means P, and m,u variances ,2 and UY2 and correlation coefficient p. We shall indicate the density by n(x, y|,ux, p,u; 2 a2; p). Suppose n observations are made on the pair (x, y) and N-n observations are made on x; that is, N-n observations on y are missing. The data are