cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling Ephraim Chambers' Knowledge Structure from a Naïve Standpoint

In the preface to his Cyclopaedia published in 1728 Ephraim Chambers offers readers a systematized structure of his attempt to produce a universal repository of human knowledge. Divided into an interconnected taxonomic tree and domain vocabulary, this structure forms the basis of one effort from the Metadata Research Center to study historical ontologies. The knowledge structure is being encoded into a Simple Knowledge Organization System (SKOS) form as well as a Web Ontology Language (OWL) version. This paper explores the expressive and functional differences between these SKOS and OWL versions of Chambers’ knowledge structure. As part of this goal, the paper research focused on the construction and application of rules in each system to produce a more computationally ready representation of Chambers’ structure in SKOS, which is more thesaurus-like, and OWL, which represents additional ontological nuances. First, studying the various textual aspects at the semantic, syntactic, and typographic levels allowed for the relationships between terms to manifest from which rules governing expression of the connections between elements developed. Second, because each language, SKOS and OWL, functionally expresses different logical relationships, their possibilities and limitations offer a ground for further analyzing the resultant knowledge structures; although, each stemmed from the same basic source of Chambers’ text. Lastly this paper will examine rule making and expression in light of Paul Grice’s theory of conversational implicature to understand how a naive agent formulates and applies these rules to a knowledge structure.
Geodesic flows and the mother of all continued fractions

We extend the Series' connection between the modular surface $\mathcal{M}=\operatorname{PSL}(2,\mathbb{Z})\backslash\mathbb{H}$, cutting sequences, and regular continued fractions to the slow converging Lehner and Farey continued fractions with digits $(1,+1)$ and $(2,-1)$ in the notation used for the Lehner continued fractions. We also introduce an alternative insertion and singularization algorithm for Farey expansions and other non-semiregular continued fractions, and an alternative dual expansion to the Farey expansions so that $\frac{dxdy}{(1+xy)^2}$ is invariant under the natural extension map.
Fermi at Trinity

Enrico Fermi estimated the yield of the Trinity test to be about 10 kilotons by dropping small pieces of paper and observing their motion in the blast wave. This is about 40% of the radiochemically derived value of $25 \pm 2$ kilotons that necessarily includes thermal and nuclear radiation that do not contribute to the blast. Although this story is classic, there appears to be no account of how he related his observation to the yield. This note attempts to reconstruct how he might have done so.
The waveguide below-cutoff attenuation standard

A semi-tutorial review of the history, development and application of waveguide below-cutoff attenuation standards is presented. A brief summary of the EM theory is followed by descriptions of the various designs implemented over a span of 60 years. Designs range from simplistic to elaborate electro-mechanical creations stretching the toolmaker's art yet ultimately dependent upon the primary standard of length.
The Open Algebraic Path Problem

The algebraic path problem provides a general setting for the Floyd--Warshall algorithm in optimization and computer science. This work extends the algebraic path problem to networks equipped with input and output boundaries. We show that the algebraic path problem is functorial as a mapping from a bicategory whose composition is gluing of open networks. In particular, we provide an isomorphism relating the solution of the path problem on a composite to the solutions on its components.
Risk Sensitive Control with Applications to Fixed Income Portfolio Management

This paper presents an application of risk sensitive control theory in financial decision making. Specifically, we develop optimal, risk-sensitive investment strategies for a long-term investor who is interested in optimal allocation of her/his capital between cash, equities and fixed income instruments. The long-term fixed income instruments used are so-called rolling-horizon bonds. In order to construct the optimal risk-sensitive control policies relevant for the present application we advance the risk sensitive control theory developed in our previous papers.
A peanut seed lipoxygenase responsive to Aspergillus colonization.

Several lines of evidence have indicated that lipoxygenase enzymes (LOX) and their products, especially 9S- and 13S-hydroperoxy fatty acids, could play a role in the Aspergillus/seed interaction. Both hydroperoxides exhibit sporogenic effects on Aspergillus spp. (Calvo, A., Hinze, L., Gardner, H.W. and Keller, N.P. 1999. Appl. Environ. Microbiol. 65: 3668–3673) and differentially modulate aflatoxin pathway gene transcription (Burow, G.B., Nesbitt, T.C., Dunlap, J. and Keller, N.P. 1997. Mol. Plant-Microbe Interact. 10: 380–387). To examine the role of seed LOXs at the molecular level, a peanut (Arachis hypogaea L.) seed gene, PnLOX1, was cloned and characterized. Analysis of nucleotide sequence suggests that PnLOX1 encodes a predicted 98 kDa protein highly similar in sequence and biochemical properties to soybean LOX2. The full-length PnLOX1 cDNA was subcloned into an expression vector to determine the type(s) of hydroperoxide products the enzyme produces. Analysis of the oxidation products of PnLOX1 revealed that it produced a mixture of 30% 9S-HPODE (9S-hydroperoxy-10E, 12Z-octadecadienoic acid) and 70% 13S-HPODE (13S-hydroperoxy-9Z, 11E-octadecadienoic acid) at pH 7. PnLOX1 is an organ-specific gene which is constitutively expressed in immature cotyledons but is highly induced by methyl jasmonate, wounding and Aspergillus infections in mature cotyledons. Examination of HPODE production in infected cotyledons suggests PnLOX1 expression may lead to an increase in 9S-HPODE in the seed.
recA protein filaments bind two molecules of single-stranded DNA with off rates regulated by nucleotide cofactor.

To probe the role of nucleotide cofactor in the binding of single-stranded DNA to recA protein, we have developed a sedimentation assay using 5'-labeled 32P-poly(dT).recA.poly(dT) complexes sediment quantitatively when centrifuged at 100,000 x g for 45 min, whereas free poly(dT) remains in the supernatant. In the presence of ATP, between 6 and 7 bases cosediment per recA monomer; but when ADP is present or in the absence of added nucleotide cofactor, only 3-3.5 bases/recA monomer cosediment. In competition experiments in which recA.32P-poly(dT) complexes are incubated with unlabeled poly(dT), we again find 3-3.5 bases of labeled poly(dT) cosedimenting per recA monomer when no nucleotide cofactor is present. However, when the same experiment is performed with ATP, only half of the expected 6-7 bases of labeled poly(dT) remain bound to the DNA, demonstrating that half of the poly(dT) in the complex exchanges rapidly with free poly(dT), whereas the other half equilibrates slowly, like poly(dT) in the absence of nucleotide. The rate of exchange of the second more tightly bound poly(dT) is accelerated when ADP is present. Our observations are rationalized by a model in which each recA protein helical filament binds two strands of poly(dT) with a stoichiometry of 3-3.5 bases/recA monomer/strand.
Local-Option Transportation Taxes: Devolution as a Revolution

The author looks at changes in the imposition of local taxes to pay for transporation; he finds some movement away from user fees. Lawmakers have been reluctant to raise user fees to meet inflation. It has been easier to try new kinds of funding, such as sales taxes, the author says.
Conservation in soil of h(2) liberated from n(2) fixation by hup nodules.

Abstract Pigeon peas (Cajanus cajan) were grown in large soil columns (90-cm length by 30-cm diameter) and inoculated with four different strains of cowpea rhizobia, which varied with respect to hydrogen uptake activity (Hup). Despite the profuse liberation of H2 from Hup- nodules in vitro, H2 gas was not detected in any of the soil columns. When H2 was injected into the columns, the rates of consumption were highest in the treatments (including control) containing Hup- nodules (218 and 177 nmol · h−1 · cm−2) and lowest in the Hup+ treatments (158, 92, and 64 nmoles · h−1 · cm−2). In situ H2 uptake rates in small soil cores at fixed distances from the nodules decreased exponentially with distance from the nodule (R2 = 0.99). This decrease in H2 consumption was associated with a similar decrease in numbers of H2-oxidizing chemolithotrophic bacteria as determined by the most-probable-number method. On the basis of two equations derived separately upon diffusive theory (Fix's Law) and kinetic theory (Michaelis-Menten), the empirically derived rate constants and coefficients indicated that all of the H2 emitted from Hup- nodules would be consumed by H2-oxidizing bacteria within a 3- to 4.5-cm radius of the nodule surface. It is concluded that H2 is not lost from the soil-plant ecosystem during N2 fixation in C. cajan but is conserved by H2-oxidizing bacteria.
Gene therapy for kidney diseases

Publisher Summary This chapter discusses the available vector systems, particularly the recombinant adeno-associated virus (rAAV) vector, methods of gene delivery to the kidney, and the potential for gene therapy as a strategy for selected renal diseases. The strategies for gene delivery for application in renal diseases depend on the nature of the underlying disease as well as on the region of the kidney and cell types involved. The unique structure–function relationships and the multiple cell types present in the kidney are major barriers to the ultimate success of gene delivery to treat kidney diseases. The development of vectors to target specific cell types in the kidney and the design of regulatable expression systems would be of great interest. Among the available gene delivery systems, rAAV vectors have several distinct advantages. rAAV has a broad host range and is capable of transducing both dividing and non-dividing cells. rAAV results in long-term transgene expression, following a single application and infects cells with no significant side effects, particularly with respect to immune responses.
Vegetation and soil development at an upland taiga site, Alaska

Vegetation and soils on fluvial deposits of different ages were used to describe ecosystem development over millennia at a well-drained taiga site in the central Alaska Range. The youngest geomorph...
Stem Cell Factor

Stem cell factor (SCF) is the ligand for the proto-oncogene c-kit. As a single agent it has only weak stimulatory effects on haemopoietic cells. However, when administered in combination with other haemopoietic growth factors it has the ability to stimulate the proliferation of committed as well as primitive haemopoietic cells.
Automated docking studies provide insights into molecular determinants of ligand recognition by N-acetyl-1-D-myo-inosityl-2-amino-2-deoxy-α-D-glucopyranoside deacetylase (MshB).

The metal-dependent deacetylase N-acetyl-1-d-myo-inosityl-2-amino-2-deoxy-α-d-glucopyranoside deacetylase (MshB) catalyzes the deacetylation of N-acetyl-1-d-myo-inosityl-2-amino-2-deoxy-α-d-glucopyranoside (GlcNAc-Ins), the committed step in mycothiol (MSH) biosynthesis. MSH is the thiol redox buffer used by mycobacteria to protect against oxidative damage and is involved in the detoxification of xenobiotics. As such, MshB is a target for the discovery of new drugs to treat tuberculosis (TB). While MshB substrate specificity and inhibitor activity have been probed extensively using enzyme kinetics, information regarding the molecular basis for the observed differences in substrate specificity and inhibitor activity is lacking. Herein we begin to examine the molecular determinants of MshB substrate specificity using automated docking studies with a set of known MshB substrates. Results from these studies offer insights into molecular recognition by MshB via identification of side chains and dynamic loops that may play roles in ligand binding. Additionally, results from these studies suggest that a hydrophobic cavity adjacent to the active site may be one important determinant of MshB substrate specificity. Importantly, this hydrophobic cavity may be advantageous for the design of MshB inhibitors with high affinity and specificity as potential TB drugs. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 406–417, 2014.
Engineering anatomically shaped vascularized bone grafts with hASCs and 3D‐printed PCL scaffolds

The treatment of large craniomaxillofacial bone defects is clinically challenging due to the limited availability of transplantable autologous bone grafts and the complex geometry of the bones. The ability to regenerate new bone tissues that faithfully replicate the anatomy would revolutionize treatment options. Advances in the field of bone tissue engineering over the past few decades offer promising new treatment alternatives using biocompatible scaffold materials and autologous cells. This approach combined with recent advances in three-dimensional (3D) printing technologies may soon allow the generation of large, bioartificial bone grafts with custom, patient-specific architecture. In this study, we use a custom-built 3D printer to develop anatomically shaped polycaprolactone (PCL) scaffolds with varying internal porosities. These scaffolds are assessed for their ability to support induction of human adipose-derived stem cells (hASCs) to form vasculature and bone, two essential components of functional bone tissue. The development of functional tissues is assessed in vitro and in vivo. Finally, we demonstrate the ability to print large mandibular and maxillary bone scaffolds that replicate fine details extracted from patient's computed tomography scans. The findings of this study illustrate the capabilities and potential of 3D printed scaffolds to be used for engineering autologous, anatomically shaped, vascularized bone grafts.
Investigation of Room Temperature Ferromagnetic Nanoparticles of Gd 5 Si 4

Gd5(Si x Ge1− x )4 compounds undergo first-order phase transitions close to room temperature when $x \tilde = 0.5$ , which are accompanied by extreme changes of properties. We report the fabrication of the nanoparticles of one of the parent compounds—Gd5Si4—using high-energy ball milling. Crystal structure, microstructure, and magnetic properties have been investigated. Particles agglomerate at long milling times, and the particles that are milled >20 min lose crystallinity and no longer undergo magnetic phase transition close to 340 K, which is present in a bulk material. The samples milled for >20 min exhibit a slightly increased coercivity. Magnetization at a high temperature of 275 K decreases with the increase in the milling time.
β2(CD11/CD18) integrins can serve as signaling partners for other leukocyte receptors

Fig. 1 depicts our current thinking about the ways in which Mo1 and p150,95 form cis interactions with other leukocyte receptors. With respect to the associations of Mo1 with Fc gamma RIIIB and uPAR, the inhibitory effect of saccharides such as NADG suggests a lectin-carbohydrate interaction that may involve the recognition of Mo1's beta-glucan site for N-linked carbohydrates4 that are expressed by both Fc gamma RIIIB and uPAR. This hypothesis is supported by the results of Stockl et al., who showed that the binding of C-terminal-specific mAb VIM12 to Mo1, which enhances the phospholipase C-mediated release of Fc gamma RIIIB, was inhibited by NADG. However, unlike the sample lectin-carbohydrate interaction that appears to govern the association between Mo1 and Fc gamma RIIIB, effective Mo1-dependent uPAR signaling also depends on the binding of intact uPA to uPAR (the receptor-binding ATF of uPA proving insufficient to prime neutrophils for an enhanced burst response to FMLP). We speculate that ATF (residues 6-135) binds to uPAR while the carboxyl terminal fragment (residues 136-411), which includes a glycosylation site at residue 144, binds to the lectinlike site of Mo1, thus fostering the linkage between the two receptors. In support of this model is the fact that exposure of neutrophils to ATF reduced the degree of molecular proximity between Mo1 and uPAR (the latter probably occupied by endogenous intact uPA) and increased the molecular association between Mo1 and Fc gamma RIIIB (both as detected by quantitative RET). This hypothesis is analogous to the concept proposed by Nykjaer et al in which plasminogen activator inhibitor-1 initially binds to uPA to form a complex that secondarily binds to the alpha 2 macroglobulin receptor, leading to internalization of the complex. Whereas the contribution of intact uPA to the interaction between Mo1 and uPAR remains speculative (based on the indirect data available), no such ambiguity exists for the role of the LPS/LBP ligand in regulating the association between Mo1 and CD14. In this circumstance, no physical linkage exists between the two receptors without the ligand complex. This observation is consistent with the previously described affinity of the beta 2 integrins for LPS, leading to the notion that the LPS portion of the LPS/LPB complex binds to Mo1, serving to link it with LPS/LBP bound to CD14. The observed reversibility of the interactions between the integrin glycoproteins and uPAR or CD14 illustrates the fact that these associations can be highly dynamic and tied to cellular processes that include directed motility (Mo1-uPAR), adherence to substrates (Mo1-CD14), and energy metabolism (p150,95-uPAR). We speculate that the GPI-anchored receptor proteins serve as rapidly diffusible, expendable "scouts" for the beta 2 integrins, which serve to expand their ligand binding repertoire in a cis-acting fashion.
Echocardiographic detection of complete and partial papillary muscle rupture during acute myocardial infarction.

L'echocardiographie permet de reconnaitre une lesion du pilier mitral avant sa rupture complete et ainsi l'intervention peut etre plus precoce
Real-time attentional models for classical conditioning and the hippocampus

Moore and Stickney (1980) described a real-time computational version of Mackintosh’s (1975) attentional model of associative learning. By assuming that hippocampal lesions affect computations that control the rate of learning, they were able to simulate impairments of latent inhibition and blocking, as reported in studies of classical conditioning. Schmajuk (1984a) proposed that hippocampal lesions affect computations of stimulus associabilities, as defined in Pearce and Hall’s (1980) model of learning. A revised version of the Moore-Stickney model and a real-time version of Pearce and Hall’s (1980) model, both incorporating the proposed modifications for the effect of hippocampal lesions, were applied to different classical conditioning paradigms. Simulation experiments with both models were carried out for the following protocols: acquisition under simultaneous, delay, and trace conditioning; partial reinforcement; noncontingent training; conditioned inhibition; differential conditioning; extinction; latent inhibition; blocking; overshadowing; and discrimination reversal. Although some discrepancies between simulation experiments and relevant literature were noted, both models proved capable of simulating most hippocampal lesion effects.
High-resolution electron microscopy studies of Ni silicides formed in lateral diffusion couples

Abstract The microstructures of silicide Ni 5 Si 2 , which formed in self-supporting Ni-Si lateral-diffusion couples, have been studied using high-resolution electron microscopy. Two polytypes for Ni 5 Si 2 have been observed and the actual composition of one polytype is confirmed to be Ni 31 Si 12 . Local variations of the crystal structure of Ni 5 Si 2 are also observed and the results are compared to computer-simulated images.
Conjugate Stress Approach for Rankine Seismic Active Earth Pressure in Cohesionless Soils

AbstractThe Rankine classic earth pressure solution has been expanded for the calculation of seismic earth pressure on rigid retaining walls supporting cohesionless backfill. The expanded solution is based on the conjugate stress concept, without employing any additional assumptions. A single formulation is used for static and pseudostatic seismic analyses of active conditions. The equation accounts for sloping backfill, as well as wall inclination, and can readily accommodate layered soil profiles and the presence of groundwater, which require tedious analysis in commonly used methods. A closed-form expression, as opposed to the constant value commonly used in practice, has been derived for the soil-wall friction angle as a function of the inertial forces and problem geometry for a given pseudostatic acceleration. Seismic lateral pressure increases with depth, and the point of application of the resultant is calculated based on stratigraphy. Comparison of the formulation with the widely used Mononobe-Oka...
Budget of Calcium Carbonate Sedimentation, Southern California Continental Borderland: ABSTRACT

Although calcareous organisms are abundant in temperate waters of the southern California continental borderland, CaCO3 is a relatively minor constituent of the sediments. Noncarbonate dilution provides only a partial explanation. Estimating rates of particulate CaCo3 mass transfer to or from that End_Page 364------------------------------ water volume in the borderland bounded above by the air-sea interface and below by the sediment-sea interface clarifies the situation. Carbonate deposition (output) totals approximately 125 × 1010 g/yr. The major carbonate mineral is Mg-calcite( 4) and aragonite. Production of 400 (g/m2)/yr by macrobenthos in shallow, hard-bottom areas is comparable to tropical, nonreef production rates. Chemical transfer involves solution (output) of about 200 × 1010 g/yr CaCO3 on basin floors. Apparently all carbonate minerals except dolomite undergo solution. These input and output estimates balance to within about 10%. Rivers entering the borderland supply only enough dissolved calcium for 30% of the CaCO3 deposited. Of the CaCO3 input to the borderland, over half dissolves, the remainder is deposited. The CaCO3 deposition rate is sufficient to extract some dissolved calcium from seawater flowing through the borderland. End_of_Article - Last_Page 365------------
The synthesis of loop predicates

Current methods for mechanical program verification require a complete predicate specification on each loop. Because this is tedious and error prone, producing a program with complete, correct predicates is reasonably difficult and would be facilitated by machine assistance. This paper discusses techniques for mechanically synthesizing loop predicates. Two classes of techniques are considered: (1) heuristic methods which derive loop predicates from boundary conditions and/or partially specified inductive assertions: (2) extraction methods which use input predicates and appropriate weak interpretations to obtain certain classes of loop predicates by an evaluation on the weak interpretation.
Studies on the prenatal toxicity and teratogenicity of N,N-diethyl benzene sulfonamide in rats.

Abstract The administration of N,N -diethyl benzene sulfonamide to pregnant rats during the period of organogenesis caused adverse effects on fetal development. In rats treated with single doses of 100, 200, 300, 400 or 500 mg/kg by the ip or intragastric route, skeletal and soft tissue abnormalities occurred in the fetuses and included unilateral and bilateral amelia, exencephalia, umbilical hernia, rotation of hind limbs and missing tails. With increasing doses, fetal weights were lowered and fetal resorptions were increased. The type and extent of expression of abnormality varied with dose, route and period of gestation.
Variability of Updraft and Downdraft Characteristics in a Large Parameter Space Study of Convective Storms

Over 200 convective storm simulations are analyzed to examine the variability in storm vertical velocity and updraft area characteristics as a function of basic environmental parameters. While it is known that bulk properties of the troposphere such as convective available potential energy (CAPE) and deep-layer wind shear exert significant influence over updraft intensity and area, additional parameters such as the temperature at the cloud base, the height of the level of free convection (LFC), and the vertical distribution of buoyancy also have an effect. For example, at low CAPE, updraft strength is strongly related to the vertical distribution of buoyancy, and also to the bulk environmental wind shear. More generally, updraft area and its temporal variability both tend to increase in environments where the LFC is raised. Additionally, in environments with persistent storms, downdraft strength is sensitive to the bulk shear, environmental temperature, and LFC height. Using multiple linear regression methods, the best combinations of environmental parameters explain up to 81% of the interexperiment variance in second-hour mean peak updraft velocity, 74% for midlevel updraft area, and 64% for downdraft velocity. Downdraft variability is explained even less well (49%) when only persistent storms are considered. These idealized simulation results show that it is easier to predict storm updraft characteristics than those of the downdraft.
APL Applications To Social Science Research An Alternative to Macrocomputer Dependent Statistical Packages

Although social science research has been greatly facilitated by the advent ofpreprogrammed "statistical packages,"such as SPSS and SAS, these generally require relatively large scale computer resources which are often unavailable to social science researchers at smaller colleges and universities. However, recent advances in computer technology have increased the availability of mini- and microlevel computers while significantly reducing equipment costs. Complementary advances in interactive programming languages have enhanced the research and instructional potentials of these new systems. In this paper, one such interactive language, APL, is discussed as to potential applications in social science research. This relatively easy to learn language is available on many large scale installations, as well as on mini-and microlevel, low cost systems. Specifically, this paper presents generalizable APL programming techniques to guide the social science researcher in the use of this language. Topics covered incl...
Aggregate output dynamics in the twentieth century

Abstract This study shows that annual output data of the G7 countries in the twentieth century are better characterized as transitory deviations from a (shifting) growth trend than as integrated processes. Furthermore, I find no two countries share common business cycles.
Hyperthermal Neutral Ar Atom Sputtering of Multilayer Thin Films of p-Xylene Adsorbed on Rh(111)†

Hyperthermal neutral Ar atoms ( = 12 eV) were used to sputter molecules from thin films of p-xylene adsorbed on Rh(111). This was done for several different film thicknesses, and the energy and intensity of the sputtered p-xylene was measured as a function of both the incident angle of the Ar and the ejection angle of the sputtered p-xylene. The first layer is not sputtered. For thicker films, up to a coverage equivalent to ∼16 layers, molecules are ejected from the surface with a yield of at most 0.05 and a translational energy of under 1 eV. For multilayer films, these results show little, if any, dependence on the film thickness. This atom-based technique is envisaged as an alternative to ion sputtering for depth profiling of organic thin films. Since it involves only low-energy neutral species, charging effects are mitigated. Moreover, the incident neutral inert gas species does not react with the surface nor alter the chemical composition of the film.
Fundamental Defect Centers in Glass: The Peroxy Radical in Irradiated, High-Purity, Fused Silica

A new fundamental radiation-induced defect in high-purity synthetic silica has been identified by electron-spin-resonance studies of $^{17}\mathrm{O}$-enriched Si${\mathrm{O}}_{2}$ as a peroxy radical ${\mathrm{O}}_{2}^{\ensuremath{-}}$ bonded to one Si in the glass matrix. The precursors of these defects are envisioned to be \ensuremath{\equiv} Si-O-O-Si \ensuremath{\equiv} structures, some of which preexist in the silica, are formed in greater numbers during neutron bombardment, and which may release an electron either during irradiation or subsequent annealing.
Enhancing the selectivity of an iron binding hydrogel

Abstract Iron overload is a critical clinical condition that can be controlled by diet and the use of iron-specific chelating agents. An effective oral formulation of an iron chelator should be nontoxic and selective toward iron while maintaining high affinity for iron. In this study, hydrogels containing 2,3 dihydroxybenzoic acid (2,3 DHBA), a portion of the metal chelating domain of enterobactin, were synthesized as a potential non-absorbed chelator for iron in the gastrointestinal tract. A series of polymeric chelators with various hydrogel:DHBA ratios were prepared. The iron-binding properties of the hydrogels were found to depend on the concentration of 2,3 DHBA groups on polymer chains. A 0.005 ratio of PAAm:DHBA was found to have an optimum affinity (log K = 27.01), selectivity, and high binding capacity for Fe(III).
Endoscopic management of afferent loop syndrome of malignant etiology

VOLUME 55, NO. 4, 2002 From the University of Texas Southwestern Medical Center at Dallas, Dallas, Texas. Reprint requests: J. Steven Burdick, MD, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75390-8887. Copyright © 2002 by the American Society for Gastrointestinal Endoscopy 0016-5107/2002/$35.00 + 0 37/4/122584 doi:10.1067/mge.2002.122584 Endoscopic management of afferent loop syndrome of malignant etiology
Inequalities and variational principles for turbulent transport

Two inequalities are proposed for the purpose of bounding from below the mean shear U′o(z) in turbulent channel flow. The first of these inequalities pertains to the energetics of the boundary layer, and the second pertains to the logarithmic form of the asymptote to Uo. These inequalities imply a maximum value of von Karman's constant, the numerical value of which lies between the measurements of Laufer (1951) and the value obtained from bulk discharge measurements in a pipe. The formalism, which contains no adjustable parameters, is then applied to the turbulent thermal convection problem, and a lower bound for the mean temperature is obtained. The minimum value of the latter at large distances from the boundary is in fair agreement with Townsend's (1959) measurements. Although the proposed inequalities have not been deduced from the equations of motion, they provide facts which may be useful in the search for new variational formulations of theturbulent transport problem.
Plotting Human Pedigrees

The MEGADATS pedigree plotting system, described in this paper, is designed to display a human pedigree on a graphics device such as a pen plotter. The plotting algorithm, which is order n in disk reads, where n is the number of individuals, is presented. Example plots are given, including a family with multiple mates and multiple original parent pairs.
One Christmas in Washington: The Secret Meeting between Roosevelt and Churchill that Changed the World – By David Bercuson and Holger Herwig

On the evening of 22 December 1941, just two weeks after the Japanese attack on Pearl Harbor, Winston Churchill arrived in Washington to create with President Roosevelt the Grand Alliance that woul...
A guide to the use of anticoagulant drugs in children

Increasing thrombotic complications in children with complex medication conditions have led to more widespread use of anticoagulants [Raffini et al. in Pediatrics 124(4):1001–8, 2009]. While current guidelines for the management of antithrombotic therapy in neonates and children exist, they are based on low- and very low-quality evidence [Monagle et al. in Chest 141(2 Suppl):e737–801S, 2012]. Despite numerous differences, current anticoagulation practice is largely extrapolated from adult studies. This is sub-optimal, particularly in neonates who have a rapidly evolving hemostatic system. The majority of pediatric patients have underlying medical conditions that may significantly influence drug choice and bleeding risk. This article reviews the use of anticoagulants in children with thrombosis, focusing on practical aspects such as dosing, monitoring, and complications. Low molecular weight heparin has become the preferred anticoagulant in children, although unfractionated heparin and warfarin remain frequently used. Other anticoagulants, including fondaparinux, direct thrombin inhibitors, and the newer target-specific oral anticoagulants are also discussed. Given the many unique challenges surrounding the use of anticoagulants in children, pediatric hospitals should have written practice guidelines as well as experienced providers to care for children with thrombosis. This is an evolving field, and further studies of the use of anticoagulants in neonates and children are greatly needed to help optimize care.
Seven xanthonolignoids from Psorospermum febrifugum

Abstract Chemical investigation of ethanolic extract of Psorospermum febrifugum has led to the isolation of seven xanthonolignoids. This paper represents the first report on the presence of xanthonolignoids in the genus Psorospermum . Five of these compounds are new natural products. Only marginal cytotoxic activity has been found to be associated with members of this group of xanthones.
Alterations in deoxynucleoside triphosphate metabolism in DNA damaged cells: Identification and consequences of poly(ADP-ribose) polymerase dependent and independent processes

Abstract Treatment of L1210 cells with increasing concentrations of MNNG produces heterogeneous perturbations of cellular deoxynucleoside triphosphate pools, with the magnitude and direction of the shift depending on the deoxynucleotide and on the concentration and time of exposure of the DNA damaging agent. 5 μM MNNG stimulated an increase in dATP, dCTP and dTTP but dGTP pools remained constant. These increases were not affected by 3-aminobenzamide, indicating that the pool size increases were produced by poly(ADP-ribose) polymerase independent reactions. 30 μM MNNG caused a time dependent decrease in dATP, dGTP, dTTP and dCTP. The dGTP pool was most drastically affected, becoming totally depleted within 3 hours. The fall in all 4 dNTP pools was substantially prevented by 3-aminobenzamide, suggesting that the decrease in dNTPs following DNA damage is mediated by a poly(ADP-ribose) polymerase dependent reaction. Severe depression of dGTP pools consequent to NAD and ATP depletion may provide a metabolic pathway for rapidly stopping DNA synthesis as a consequence of DNA damage and the activation of poly(ADP-ribose) polymerase.
Effects of methylphenidate on rat endurance performance and neuromuscular transmission in vitro.

The studies were designed to evaluate the effects of methylphenidate on endurance performance in vivo and on neuromuscular transmission in the isolated rat phrenic nerve-diaphragm preparation. Methylphenidate produced a biphasic effect on treadmill endurance performance, increasing running times by 41–61% at 2.5–5 mg/kg, while reducing running times by 35% at 20 mg/kg. A biphasic effect on nerve-stimulated muscle concentrations was also observed, with twitch tension increased by up to 49–106% at low concentrations (0.1–0.3 mM) and blocked at high concentrations (0.6–1.0 mM). Tissues obtained from rats pretreated with α-methyl-p-tyrosine or reserpine exhibited no change in twitch height. Methylphenidate failed to protect against irreversible blocking of the twitch by α-bungarotoxin and did not modify the resting membrane potential, miniature endplate potential (MEPP) frequency or nerve-stimulated acetylcholine release. High concentrations reduced the amplitudes of the MEPP and endplate potential. Whereas methylphenidate and amphetamine both produced biphasic effects on skeletal muscle contractions in vitro, they act by different neuropharmacological mechanisms. Unlike amphetamine, the biphasic effects of methylphenidate are produced by mechanisms that are independent of cholinergic or adrenergic interactions and may involve direct effects on the muscle.
A new methodology for phase-locking value: a measure of true dynamic functional connectivity

Phase-Locking value (PLV) is used to measure phase synchrony of narrowband signals, therefore, it is able to provide a measure of dynamic functional connectivity (DFC) of brain interactions. Currently used PLV methods compute the convolution of the signal at the target frequency with a complex Gabor wavelet centered at that frequency. The phase of this convolution is extracted for all time-bins over trials for a pair of neural signals. These time-bins set a limit on the temporal resolution for PLV, hence, for DFC. Therefore, these methods cannot provide a true DFC in a strict sense. PLV is defined as the absolute value of the characteristic function of the difference of instantaneous phases (IP) of two analytic signals evaluated at s = 1. It is a function of the time. For the narrowband signal in the stationary Gaussian white noise, we investigated statistics of (i) its phase, (ii) the maximum likelihood estimate of its phase, and (iii) the phase-lock loop (PLL) measurement of its phase, derived the analytic form of the probability density function (pdf) of the difference of IP, and expressed this pdf in terms of signal-to-noise ratio (SNR) of signals. PLV is finally given by analytic formulas in terms of SNRs of a pair of neural signals under investigation. In this new approach, SNR, hence PLV, is evaluated at any time instant over repeated trials. Thus, the new approach can provide a true DFC via PLV. This paper presents detailed derivations of this approach and results obtained by using simulations for magnetoencephalography (MEG) data.
Why people don't learn from diabetes literature: influence of text and reader characteristics

The study was designed to identify text and reader characteristics that impede learning. Twenty-six adults with diabetes mellitus took a 15-item test for prior knowledge of diabetes, a 20-item vocabulary test, and a Need for Cognition questionnaire. Immediately after reading an excerpt from a commonly used diabetes pamphlet, they could recall an average of only eight of the 108 ideas in it. Readers seldom monitored their comprehension. Also, the topics that they thought were important differed from the topics that a physician thought were important. Many readers lacked reading skills, but those with high need for cognition and higher vocabulary scores recalled more topics. Even with an appropriate reading level, text characteristics that could hinder comprehension included lack of organization and clarity.
Values Hierarchies and Moral Reasoning

(1993). Values Hierarchies and Moral Reasoning. The Journal of Social Psychology: Vol. 133, No. 6, pp. 869-871.
Influence of pH on the Transport of Silver Nanoparticles in Saturated Porous Media: Laboratory Experiments and Modeling

Given the ubiquity of silver nanoparticles (AgNPs) and their potential for toxic effects on both humans and the environment, it is important to understand their environmental fate and transport. The purpose of this study is to gain information on the transport properties of commercial AgNP suspensions in a glass bead-packed column under saturated flow conditions at different solution pH levels. Commercial AgNPs were characterized using high-resolution transmission electron microscopy, dynamic light scattering, X-ray photoelectron spectroscopy, ultraviolet visible spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. Transport data were collected at different pH levels (4, 6.5, 9, and 11) at fixed ionic strength. Capture of AgNPs increased as the pH of the solution increased from 4 to 6.5. Further increase in pH to 9 and 11 decreased the attachment of AgNPs to the glass beads. AgNP concentration versus time breakthrough data were simulated using an advection–dispersion model incorporating both irreversible and reversible attachment. In particular, a reversible attachment model is required to simulate breakthrough curve tailing at near neutral pH, when attachment is most significant. The laboratory and modeling study reveals that for natural groundwaters, AgNP transport in porous media may be retarded due to capture; but ultimately, most of the mass may be slowly released over time.
HIV Disease and Pregnancy: Part 1. Epidemiology, Pathogenesis, and Natural History

Women constitute the fastest growing component of the human immunodeficiency virus (HIV) epidemic. The majority of women with HIV disease are of reproductive age, and perinatally acquired HIV infection has increased proportionately. The nurse needs knowledge about the unique interactions between HIV infection and pregnancy to provide the complex care required during the perinatal period. An overview of the epidemiology, pathogenesis, and natural history of HIV disease focusing on women is presented. The effects of pregnancy on the progression of HIV disease and the effects of HIV disease on pregnancy outcomes are explored.
Effect of ozone exposure on lung functions and plasma prostaglandin and thromboxane concentrations in guinea pigs

Male Hartley guinea pigs were exposed either to filtered air or to 1 ppm ozone (O/sub 3/) for 1 hr. At 2, 8, 24, or 48 hr after exposure we measured ventilation, respiratory mechanics, lung volumes, diffusing capacity for carbon monoxide (DLCO), and alveolar volume (VA) in anesthetized, tracheotomized animals. Respiratory frequency and tidal volume were unchanged in all groups. Pulmonary resistance was increased 2 hr after O/sub 3/ but returned to control at 8 hr and thereafter. Prolonged reductions in lung volumes (total lung capacity, vital capacity, functional residual capacity, and residual volume) as well as in DLCO and VA occurred after O/sub 3/, with maximum decreases at 8 and 24 hr postexposure. Increased ratios of wet lung weight to body weight were seen at 2, 8, and 24 hr. In separate groups of animals, also exposed either to filtered air or to 1 ppm O/sub 3/, plasma eicosanoid (EC) concentrations were measured at 2, 8, 24, 48, or 72 hr after exposure. Significant increases in thromboxane B2 concentrations were seen at 2, 24, and 48 hr after exposure. Plasma concentrations of 6-keto prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E1 (PGE1) were increased at 24 hr and atmore » 24, 48, and 72 hr, respectively. The nature of this long-term pulmonary response to a short-term exposure to O/sub 3/ suggests alveolar involvement, including probable alveolar duct constriction and localized pulmonary edema. Although changes in plasma EC concentrations were observed concurrent with impaired lung functions, no simple causal relationship was apparent from these studies.« less
Gut flora antigens are not important in the maintenance of regulatory T cell heterogeneity and homeostasis

CD25+ regulatory T cells (Treg) are a heterogeneous population that exists as CD44low and CD44high cells. Here we report that while both CD44low and CD44high Treg are anergic and express similar levels of Foxp3, CD44high Treg are highly proliferative in vivo and are more potent suppressors in vitro than CD44low Treg. From analysis of the properties of Treg derived from germ-free mice, it was concluded that peptide antigens derived from intestinal microorganisms are not essential for the generation, in vivo proliferation or suppressive activity of Treg. Our results suggest that gut flora antigens play little or no role in the heterogeneity and homeostatic regulation of Treg.
A monte carlo method for foutz's goodness-of-fit test

We propose a methos for approximating the p-value of a goodness-of-fit test developed by Foutz (1980). This approximation is based on a Monte Carlo method and is compared with the normal approximation and Franke and Jayachandran's (1983) approximation. Two examples, including one bivariate case, are given.
Lipid signalling pathways in normal and ras-transfected in NIH/3T3 cells

Abstract The role of ras oncogenes in cellular signalling pathways involving phospholipid breakdown was studies in untransfected and photo-H-ras and mutated H-, k- and N-ras transfected NIH/3T3 cells. When the cells were grown at low cell densities, all of the Pras transfected cells had 2–4 fold hinger diacylglycerol (DAG) levels compared to growing NIH/3T3 cells. At high cells. At high cell densities, DAG levels decreased in the former and increased in contact inhibited NIH/3T3 cells. In this regard, only cells transformed by mutated cellular and viral H-ras oncogenes (but not by the H-ras proto-oncogene) had elevated DAG levels compared to contact inhibited NIH/3T3 cells. The basal levels of inositol phosphates in ras transfected cells were not significantly different from NIH/3T3 cells and did not vary with cell density. Thus, the elevated DAG levels are not a consequences of increased phosphoinositide hydrolysis. The latter was stimulated by serum and bombesin only in normal and photo-H-ras transfected cells. In contrast, stimulation by bradykinin was observed only in cells trasnformed by mutated cellular ras oncogenes. Furthermore, aluminum fluoride stimulated phosphoinositide breakdown in the latter cells indicating that there was no uncoupling of the G protein from phospholipase C. Treatment of ras transfected cell with dibutyryl cyclic AMP (DB-cAMP), which causes an inhibition of growth and a reversal of the transformed morphology, did not alter the basal levels of inositol phosphates. DB-cAMP, however, did lower DAG levels in some of the transformed cell lines, but elevated DAG levels in low density NIH/3T3 cells. These findings indicate that the ras gene product p21 is not involved in phosphoinositide hydrolysis and that DAG levels do not correlate with cell growth in either normal or ras transfected NIH/3T3 cells. Thus, p21 appears to alter cell growth through mechanism(s) independent of lipid signalling pathways.
Emerging Applications of Riboswitches in Chemical Biology

Living systems use RNA sequences known as riboswitches to detect the concentrations of small-molecule metabolites within cells and to regulate the expression of genes that produce these metabolites. Like their natural counterparts, synthetic riboswitches also regulate gene expression in response to small molecules. Because synthetic riboswitches can be engineered to respond to nonendogenous small molecules, they are powerful tools for chemical and synthetic biologists interested in understanding and reprogramming cellular behavior. In this review, we present an overview of natural riboswitches, highlight recent studies toward developing synthetic riboswitches and provide an overview of emerging applications of these RNA switches in chemical biology.
Reading Colonial Records Through an Archival Lens: The Provenance of Place, Space and Creation

Analyzes attitudes and use of archives by post-colonial scholars who find that colonial records offer the voices of the master narrative but do not reflect the voices of the oppressed and voiceless. Argues that framing records within social provenance and a ‘community of records’ offers archival solutions to the dilemmas of locating all voices within the spaces of records.