cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure and Expression of the FlaA Periplasmic Flagellar Protein of Borrelia burgdorferi

The spirochete which causes Lyme disease, Borrelia burgdorferi, has many features common to other spirochete species. Outermost is a membrane sheath, and within this sheath are the cell cylinder and periplasmic flagella (PFs). The PFs are subterminally attached to the cell cylinder and overlap in the center of the cell. Most descriptions of the B. burgdorferi flagellar filaments indicate that these organelles consist of only one flagellin protein (FlaB). In contrast, the PFs from other spirochete species are comprised of an outer layer of FlaA and a core of FlaB. We recently found that a flaA homolog was expressed in B. burgdorferi and that it mapped in a fla/che operon. These results led us to analyze the PFs and FlaA of B. burgdorferi in detail. Using Triton X-100 to remove the outer membrane and isolate the PFs, we found that the 38.0-kDa FlaA protein purified with the PFs in association with the 41.0-kDa FlaB protein. On the other hand, purifying the PFs by using Sarkosyl resulted in no FlaA in the isolated PFs. Sarkosyl has been used by others to purify B. burgdorferi PFs, and our results explain in part their failure to find FlaA. Unlike other spirochetes, B. burgdorferi FlaA was expressed at a lower level than FlaB. In characterizing FlaA, we found that it was posttranslationally modified by glycosylation, and thus it resembles its counterpart from Serpulina hyodysenteriae. We also tested if FlaA was synthesized in a spontaneously occurring PF mutant of B. burgdorferi (HB19Fla-). Although this mutant still synthesized flaA message in amounts similar to the wild-type amounts, it failed to synthesize FlaA protein. These results suggest that, in agreement with data found for FlaB and other spirochete flagellar proteins, FlaA is likely to be regulated on the translational level. Western blot analysis using Treponema pallidum anti-FlaA serum indicated that FlaA was antigenically well conserved in several spirochete species. Taken together, the results indicate that both FlaA and FlaB comprise the PFs of B. burgdorferi and that they are regulated differently from flagellin proteins of other bacteria.
Chlamydia vaccine: progress and challenges.

The accumulated body of evidence has provided important guiding principles for Chlamydia vaccine development. They are: (i) whole-organism vaccine preparations may be efficacious, as animal studies and the trachoma trials have suggested; (ii) a multisub-unit component vaccine should likely include combinations of serovar/biovar-specific protective antigens; and (iii) the prevention of pathological sequelae and the reduction of the incidence of infection should be the driving forces in vaccine development. Live chlamydial infections induce the best protective immunity in both humans and mice when compared to immunization with either dead organisms or component antigens. In a gel electrophoresis and immunoblotting approach, chlamydial antigens derived from purified organisms or Chlamydia-infected cells are subjected to two-dimensional gel electrophoresis (2D-GE) and then probed with sera from Chlamydia-seropositive humans. Chlamydial proteins are labeled during growth with radioactive amino acids, and individual antigens from lysed chlamydial organisms or Chlamydia-infected cells that are recognized by patient sera are first immunoprecipitated and then resolved using 2D-GE. A genome expression library screen for immunogenicity followed by DNA immunization has been used to identify four housekeeping genes that induced robust protective immunity against Chlamydia abortus lung infection in mice. Collectively, contemporary technologies have enabled considerable progress in Chlamydia vaccine development in the recent past, but several issues remain to be addressed before advancing the identified antigens into human clinical trials.
Solubilization and Properties of a Particulate Hydrogenase from Methanobacterium Strain G2R

Mechanical disruption of cells of Methanobacterium strain G2R resulted in a 78-fold increase in the specific activity of the hydrogenase as measured by the benzyl viologen reduction assay. Approximately 50% of the activity in disrupted cells was associated with the particulate fraction. Between 69 and 85% of the particulate hydrogenase was released by treatment with the detergents Triton X-100, deoxycholate, and octyl-beta-d-glucopyranoside. The relative electrophoretic mobilities of the soluble hydrogenases were identical, indicating that G2R possessed a single electrophoretically distinct hydrogenase. The particulate enzyme was inactivated by oxygen and could be reactivated with dithionite or glucose plus glucose oxidase. The enzyme had a pH optimum of 8.5 and resisted heating at 52 but not 77 degrees C. A number of nonspecific dyes, flavin adenine dinucleotide, and riboflavin 5'-phosphate were effective electron acceptors; oxidized nicotinamide adenine dinucleotide, nicotinamide adenine dinucleotide phosphate, and factor 420 were apparently not reduced. Hydrogenase activity was inhibited by p-hydroxymercuribenzoate, cyanide, chloroform, and chloramphenicol. The molecular weight of the solubilized enzyme was 900,000, with subunits of molecular weights 38,500, 50,700, and approximately 80,000. It is suggested that, in intact cells of G2R, the large hydrogenase complex is loosely bound to the cell wall or membrane.
Fasting-induced increases in food intake and neuropeptide Y gene expression are attenuated in aging male brown Norway rats.

Aging in man is associated with alterations in food intake (FI) and body weight (BW). To establish a model of age-related alterations in FI and BW regulation, FI and BW were determined in young (3-month-old), middle-aged (12-month-old), and old (24-month-old) male Brown Norway rats during ad libitum feeding and after 72 h of fasting. FI was reduced with aging both during ad libitum feeding and after fasting. With fasting, young rats lost more BW than older rats, but regained BW more rapidly during refeeding. To determine whether age-related impairments in FI and BW regulation are mediated by neuropeptide Y (NPY), a potent stimulator of FI, we compared arcuate nucleus prepro-NPY (ppNPY) messenger RNA (mRNA) by in situ hybridization in fasted and ad libitum-fed (fed) young, middle-aged, and old rats. ppNPY mRNA declined with aging in both fed and fasted rats. Although ppNPY mRNA increased with fasting in all age groups, this response was attenuated with aging. In conclusion, impaired FI and BW recovery afte...
The equivalence of the electric and magnetic surface current approaches in microstrip antenna studies

It is shown that the fields produced by the electric surface currents on the conducting patch of a microstrip antenna are equivalent to those produced by a magnetic surface current sheet bounding the patch in the substrate only when dyadic Green's functions for the two-layer stratified medium are used.
Memory Span as a Function of Amount of Information

Memory span for binary, quaternary, octal, and hexadecimal digits, containing 1, 2, 3, and 4 bits of information per item respectively, was determined for 4 independent groups of 25 college Ss. Except for comparison of quaternary and octal digits, memory span in item units decreased as a function of amount of information per item. The results were interpreted as inconsistent with a “constant-chunk” hypothesis and providing further support for an explanation based on reduction of redundancy.
Wavelet-based fractal signature analysis for automatic target recognition

Texture measures offer a means of detecting targets in back- ground clutter that has similar spectral characteristics. Our previous studies demonstrated that the ''fractal signature'' (a feature set based on the fractal surface area function) is very accurate and robust for gray- scale texture classification. This paper introduces a new multichannel texture model that characterizes patterns as 2-D functions in a Besov space. The wavelet-based fractal signature generates an n-dimensional surface, which is used for classification. Results of some experimental studies are presented demonstrating the usefulness of this texture mea- sure. © 1998 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(98)01001-0)
Institutions and urban revitalization: The case of Chelsea in New York City

The emergent institutionalist perspective in urban geography has recently been applied to explain neighborhood revitalization in a number of seminal analyses. This research on Chelsea in New York City extends this body of theory by considering how the effect of institutional activity on neighborhood revitalization is itself constrained by the activities of other institutions. The research examines the wide range of institutions whose conflicting objectives, values, and activities played a role in funneling reinvestment into Chelsea between 1970 and 1980. The results suggest that an understanding of the neighborhood revitalization process can be substantially advanced by focusing on the prerequisite social, political, and economic resources necessary for its unfolding. Local managers operate under subjective value orientationsbeing influenced themselves by the power of other competing and conflicting institutions- which control and direct access to scarce resources.
PARASITE-MEDIATED COMPETITION : A MODEL OF DIRECTLY TRANSMITTED MACROPARASITES

There is growing interest in host-parasite ecology, particularly with regard to the effect of parasites on host community structure, but few studies have explored the theory of parasite mediation of host competition. I developed a model to examine the impact of directly transmitted macroparasites on the competition and population dynamics of two sympatric host species. Several important features of macroparasite-mediated competition are considered in the model: the two host species compete in a classical Lotka-Volterra manner, the parasite influences the survivorship and reproduction of both hosts, and parasites exhibit aggregated distribution among host populations. The conditions for host coexistence were derived explicitly. The results suggest that host intrinsic growth rate, host carrying capacity, susceptibility, parasite pathogenicity, and the magnitude of parasite aggregation are important components influencing host coexistence. Parasites may enhance or disrupt host coexistence, depending on the r...
Linking Life and Literature in Early Childhood Settings

Using an example of a toddler’s developing understanding of an apple, this article illustrates how children integrate all elements in their interpersonal and built environments to support their emerging literacy skills. Otto (2007) and others provide evidence from emergent literacy research that documents observations and exploration by infants, toddlers, and young children and suggest that the ways in which children participate in early literature-related activities influence the knowledge they construct. Twenty-two children’s books—including five for apple discoverers—are recommended and reviewed.
Thrombocytosis : When is an incidental finding serious?

For most patients, elevated platelet counts are benign and require no treatment, but for some, severe complications or death may ensue. This article discusses how to classify thrombocytosis and identify which patients require treatment, describes the characteristic complications that may arise, and provides an algorithm for management.
A reviewer's guide to the grounded theory methodology in logistics and supply chain management research

Purpose – The purpose of this paper is to analyze previous grounded theory articles and, based on this analysis, to provide a framework to assist reviewers in evaluating grounded theory research and increasing the rigor and credibility of this methodology in logistics and supply chain journals.Design/methodology/approach – An analysis of existing articles appearing in the leading logistics and supply chain journals combined with an extensive review of the grounded theory method literature were used to develop a comprehensive framework for evaluating grounded theory research.Findings – The paper finds that no standard criteria for publication of grounded theory research exists in logistics and supply chain journals. Grounded theory is routinely confused with other qualitative methodologies. Overall, this situation leads to publications that do not adequately address or report on the process for developing a grounded theory.Research limitations/implications – Reviewers can use this paper to establish the qu...
Efficient solution of non-Markovian covariance evolution equations in fluid turbulence

A method is described for efficient treatment of the time-history effects that arise in closure models constructed by truncation of renormalized perturbation expansions. The scheme is based on rational polynomial (Pade) approximations for the time-lagged functions, combined with Gaussian quadrature applied to a coarse-time evolution equation for equal-time covariances. Power series coefficients required for the Pade approximants are generated by recursion relations resulting from successive differentiation of the slow-varying form of the dynamic equations for time-lagged functions. This strategy is illustrated by applications to equations of the direct interaction approximation for fluid turbulence. Several benefits accrue from such an approach. Computational efficiency comparable to that of Markovian closures is obtained without introduction of arbitrary constants orad hoc Markovianization assumptions: (1) Scaling of the leading operations count is reduced fromO(n T 3 ) toO(n g n t ), wheren T is the number of steps in coarse time, and ng≈ 4–8. For typical problems in fluid turbulence, this results in savings of afactor∼40 in computing time. (2) Scaling of working array size is reduced fromO(n T 2 ) toO(p), wherep is the order of Pade approximant; this reduces in-core storage requirements for dynamical quantities by afactor ∼20. These and other advantages depend on the order of Pade approximant required to give acceptable accuracy. Test cases from several problems in fluid turbulence indicate very substantial savings, such that certain CPU-intensive problems with spatial inhomogeneities become computationally feasible.
Evidence for Induction of Interferon-α and Interferon-β in Retinal Glial Cells of Müller

Abstract Studies were performed to determine if retinal glial cells of Muller transcribe the genes for interferon-α (IFNα) or IFNβ upon exposure to virus. Responses to herpes simplex virus type 1 (HSV-1) were tested with cultured murine Muller cells and, in vivo, with retinas obtained after bilateral injection of either HSV-1 or buffer into the anterior chamber of the eyes of BALB/c mice. Induction of IFN transcription and relative temporal changes in transcript levels occurred over time after either in vitro or in vivo exposure to HSV-1. Transcription of both IFN genes was induced in cultured glia within 1 hr after exposure to virus. IFN transcripts were detected in retinas by 24 hr postinfection and these were maximal at 3 days. By in situ hybridization (ISH), IFNα 2 mRNA localized to focal areas in the intact retinas of virus-injected eyes and was consistent with our previous report of a transient, focal appearance of viral antigens in those retinas. Uninfected cells and ocular tissues were negative for IFN transcripts. Combined ISH and immunohistochemistry on retinal impression smears confirmed that glial fibrillary acidic protein-positive Muller cells are an intraretinal source of IFNα and IFNβ transcripts after ocular exposure to HSV-1. Our results support a role for Muller cells as participants in intraretinal antiviral or immunomodulatory responses via type 1 IFN production and may have implications for future therapeutic interventions.
Object detection through matched wavelet transforms

The paper provides a closed form solution to least squares matching of the energy spectrum density of an orthonormal MRA-generating wavelet with that of a specified arbitrary signal. The authors had previously proposed algorithms for matching with samples of energy spectrum densities. An approach is also proposed to use matched wavelets in detecting an object in an image. Furthermore, the approach captures size, orientation and position information.
Nonlinear Semianalytical Finite-Element Algorithm for the Analysis of Internal Resonance Conditions in Complex Waveguides

AbstractResearch efforts on nonlinear guided wave propagation have increased dramatically in the last few decades because of the high sensitivity of nonlinear waves to structural conditions (defects, quasi-static loads, instability conditions, and so on). However, the mathematical framework governing the nonlinear guided wave phenomena becomes extremely challenging in waveguides that are complex in either materials (damping, anisotropy, heterogeneous, etc.) or geometry (multilayers, geometric periodicity, etc.). The present work develops predictions of nonlinear second-harmonic generation in complex waveguides by implementing a semianalytical finite-element formulation that accounts for material nonlinearities into a highly flexible, yet very powerful, commercial finite-element code. Once formulated correctly, the proposed analysis can easily take into account damping effects, anisotropic multilayered properties, periodic geometries, and other complex waveguide properties in a computational efficient and ...
Fermilab Tevatron signatures of long-lived charged sleptons in gauge-mediated supersymmetry breaking models

In supersymmetric models with gauge-mediated supersymmetry breaking, charged sleptons are the next lightest supersymmetric particles and decay outside the detector for large regions of parameter space. In such scenarios, supersymmetry may be discovered by searches for a number of novel signals, including highly ionizing tracks from long-lived slow charged particles and excesses of multi-lepton signals. We consider this scenario in detail and find that the currently available Fermilab Tevatron data probe regions of parameter space beyond the kinematic reach of CERN LEP II. Future Tevatron runs with integrated luminosities of 2, 10, and 30thinspfb{sup {minus}1} probe right-handed slepton masses of 110, 180, and 230 GeV and W-ino masses of 310, 370, and 420 GeV, respectively, greatly extending current search limits. {copyright} {ital 1998} {ital The American Physical Society}
Study of differentiation of fresh myeloid leukemic cells by physiologic agents that induce a human promyelocytic leukemic line (HL-60) to differentiate.

Abstract A promyelocytic cell line known as HL-60 can be induced to mature to granulocytes or monocytes after exposure to a variety of physiologic agents including 1-α25 dihydroxy Vitamin D 3 (Vit D), retinoic acid, cyclic AMP cell permeant compounds, and stimulators of adenylate cyclase. These compounds were used in primary culture of blast cells from 12 patients with acute nonlymphocytic leukemia. Maturation was assessed by morphology, superoxide production, development of esterase activity and chemotactic peptide receptor expression. Morphologic maturation and superoxide production correlated with chemotactic peptide receptor expression. The majority of blast cells treated with inducer showed no significant change in morphologic or functional markers compared to the blast cells cultured in fresh media alone. Chemotactic peptide receptor expression increased 3 to 30-fold in 13 of 14 cases studied. In 4 patients, the highest receptor expression was without inducer and in 4 patients the highest increase was with dibutyryl cyclic AMP treatment. Our study suggests that physiologic inducers of HL-60 differentiation do not consistently have the same effect on primary suspension culture of freshly isolated human leukemia cells.
Modeling the impedance versus voltage characteristics of LiNi0.8Co0.15Al0.05O2

Abstract The power-delivery capability of lithium-ion cells based on LiNi 0.8 Co 0.15 Al 0.05 O 2 -based positive electrodes shows a significant dependence on the cell's state-of-charge. One reason for this behavior is the variation of the positive electrode's impedance with the oxide's lithium content. In this article, an electrochemical model based on concentrated solution porous electrode theory is used to model impedance data obtained on LiNi 0.8 Co 0.15 Al 0.05 O 2 -based positive electrodes charged to potentials ranging from 3.55 to 4.55 V versus Li. The parameters obtained from model fits include the exchange-current density and Li-ion diffusion coefficients in the oxide. The variations in these parameters with oxide potential are correlated with structural changes in the material observed during Li-ion intercalation–deintercalation reactions.
16.3″ QSXGA high resolution wide viewing angle TFT-LCDs based on ridge and fringe-field structures

Abstract In 1998, the IBM display group demonstrated a 16.3″ diagonal QSXGA (Quad SXGA) direct view TFT-LCD with the highest information content ever shown [17] . The panel has 2560×3 columns and 2048 rows and the subpixel size is 42 μm (h)×126 μm (v) which is equivalent to a full color resolution of 200 ppi (pixel per inch). In this panel, the conventional single domain twisted nematic (TN) liquid crystal mode was adopted, i.e. no wide viewing angle technology was implemented. In this paper, we demonstrated that the ridge and fringe field technology [18] can be implemented in this high resolution liquid crystal display to achieve wide viewing angle capability.
Personality characteristics of women's liberation activists as measured by the MMPI.

Summary.-The study was designed to explore the validity of notions held by the women's Liberation movement regarding personaliry characteristics of movement activists. Two groups, one composed of 19 college student activists in the women's liberation movement and the other composed of 34 female college students, were given a computer-administered MMPI. ne results do not support rhe imputations that these college student activists in che women's liberation movement exhibit deviant personality characteristics or that they are more maladjusted than control subjects.
The Molecular Basis of Gonadotropin-Releasing Hormone Action*

Introduction WE HAVE known for more than 15 yr that release of the pituitary gonadotropins (LH and FSH) is regulated by a decapeptide from the hypothalamus, GnRH. This releasing hormone is active in vivo, as well as in pituitary explants, and in cell cultures. Accordingly, it has been possible to obtain a great deal of data which have been used to develop an understanding of GnRH action at the cellular level. Models of GnRH action have been useful to understand and predict the actions of GnRH in vivo and to design means for using the releasing hormone in the treatment of human disorders. The present review will describe our current understanding of GnRH action and serve to update our previous review in this series (1).
Effective Age of Remanufactured Products: An Entropy Approach

Product take-back and remanufacturing systems are difficult to implement cost effectively. One contributing factor is the complex nature of the inter-relationships among components of a product. Modeling of these relationships helps determine the product’s overall performance as a function of the performances of individual components. Reliability, a commonly used measure of performance, is a good measure of the physical failure rate, but it does not always reflect value degradation as experienced by customers or experts. As a result, it is difficult to define the effective performance of remanufactured products when some components are reused while others are not. Legislated take-back mandates across the world increasingly make it necessary to understand this perceived performance. In this paper we propose a method for combining customers’/experts’ assessments of value degradation using the maximum entropy principle. This value degradation information is then coupled with the components’ failure rate information. A method for modeling performance of a product that is comprised of components of different ages is presented. Overall performance is measured in units of time (effective age) by aligning with that of a product that has never been disassembled. We demonstrate the approach using a personal computer as example.
Affective Reactions to Leadership Education: An Exploration of the Same-Gender Effect:

This study examines influences of the gender of participants and of small group leaders on the affective reactions of experienced managers attending a 1-week residential training program on leaders...
Conformational characteristics of peptides and unanticipated results from crystal structure analyses

Preferred conformation and types of molecular folding are some of the topics that can be addressed by structure analysis using x-ray diffraction of single crystals. The conformations of small linear peptide molecules with 2–6 residues are affected by polarity of solvent, presence of water molecules, hydrogen bonding with neighboring molecules, and other packing forces. Larger peptides, both cyclic and linear, have many intramolecular hydrogen bonds, the effect of which outweighs any intermolecular attractions. Numerous polymorphs of decapeptides grown from a variety of solvents, with different cocrystallized solvents, show a constant conformation for each peptide. Large conformational changes occur, however, upon complexation with metal ions. A new form of free valinomycin grown from DMSO exhibits near three-fold symmetry with only three intramolecular hydrogen bonds. The peptide is in the form of a shallow bowl with a hydrophobic exterior. Near the bottom of the interior of the bowl are three carbonyl oxygens, spaced and directed so that they are in position to form three ligands to a K+, e.g., complexation can be completed by the three lobes containing the β-bends closing over and encapsulating the K+ ion. In another example, free antamanide and the biologically inactive perhydro analogue, in which four phenyl groups become cyclic hexyl groups, have essentially the same folding of backbone and side chains. The conformation changes drastically upon complexation with Li+ or Na+. However, the metal ion complex of natural antamanide has a hydrophobic globlar form whereas the metal ion complex of the inactive perhydro analogue has a polar band around the middle. The structure results indicate that the antamanide molecule is in a complexed form during its biological activity. Single crystal x-ray diffraction structure analyses have identified the manner in which water molecules are essential to creating minipolar areas on apolar helices. Completely apolar peptides, such as membrane-active peptides, can acquire amphiphilic character by insertion of a water molecule into the helical backbone of Boc-Aib-Ala-Leu-Aib-Ala-Leu-Aib-Ala-Leu-Aib-OMe, for example. The C-terminal half assumes an α-helix conformation, whereas the N-terminal half is distorted by an insertion of a water molecule W(1) between N(Ala5) and O(Ala2), forming and hydrogen bonds N(5)H W(1) and W(1) O(2). The distortion of the helix exposes CO (Aib1) and CO (Aib4) to the outside environment with the consequence of attracting additional water molecules. The leucyl side chains are on the other side of the molecule. Thus a helix with an apolar sequence can mimic an amphiphilic helix.
Genetic traumatic occlusion in the mouse.

The dramatic alveolar bone loss associated with a developmental genetic traumatic occlusion in the ‘crinkled’ mutant (cr/cr) of the house moose is described from osteological and radiographic investigations. Bone loss is severe palatally, buccally and interdentally in the upper molar teeth and lingually in the lowers. This is associated with severe and abnormal tooth wear when compared to normal mice and could also be associated with changes in the temporomandibular joint. Possible uses in periodontal research are suggested.
Diffusion of cations in the anodic oxidation of metals: numerical calculations☆

Abstract The current/time curve of anodic oxidation of metals at constant potential is analysed quantitatively under specific assumptions. The concentration distribution of interstitial metal ion in bulk oxide is calculated on the basis of a diffusion model. It is concluded that the reaction rate is controlled by diffusion if the slope of log i/log (time) 1 2 plot is −1 at constant potential.
Advances in H2O thermodynamics

It is widely appreciated in geophysics that the thermodynamic properties of water need to be better known, and there is a good chance that they will be, as a result of recent advances in the development of three atom pair distribution functions for water by A.H. Narten, W.E. Theissen, and L. Blum (Science, Sept. 10, 1982). Research in atmospherics, oceans, glaciers, metasomatism, and many other areas of geophysics has been subject to a serious limitation, namely the lack of knowledge of the structure of liquid water, H2O. The new results were obtained by means of high-flux neutron diffraction data, which are of considerably higher quality than past data. New distribution functions based on the measurements may lead to development of a more realistic statistical mechanical theory of liquid water.
A reanalysis of B0-B0 mixing in e+e- annihilation at 29 GeV

Abstract Data taken by the Mark II detector at the PEP storage ring was used to measure the rate of dilepton production in multihadronic events produced by e + e − annihilation at √ s =29 GeV. We determine the probability that a hadron initially containing a b (b) quark decays to a positive (negative) lepton to be 0.17 −0.08 +0.15 , with 90% confidence level limits of 0.06 and 0.38.
Low frequency Raman spectra of chalcogenide glasses

Abstract Low frequency ( -1 ) Raman scattering lineshapes for the chalcogenide glasses As 2 S 3 and As 2 Se 3 have been interpreted in terms of a model which explicitly includes acoustic (∼ ω2 density-of-states) and optic (rigid-layer like) vibrational modes.
Selection of steady states in the two-dimensional symmetric model of dendritic growth

Selection of steady needle crystals in the full nonlocal symmetric model of dendritic growth is considered. The diffusion equation and associated kinematic and thermodynamic boundary conditions are recast into a nonlinear integral equation which is solved numerically. For the range of Peclet numbers and capillarity lengths considered it is found that a smooth solution exists only if anisotropy is included in the capillarity term of the Gibbs-Thomson condition. The behavior of the selected velocity and tip radius as a function of undercooling is also examined.
BIOASSAY OF THE PITUITARY GROWTH HORMONE. WIDTH OF THE PROXIMAL EPIPHYSIAL CARTILAE OF THE TIBIA IN HYPOPHYSECTOMI2ED RATS1,2

HYPOPHYSECTOMY causes regressive changes at the proximal end of the tibia in the immature rat, as described by various authors (1–4). Within a few days, the thickness of the cartilage plate decreases significantly, a consequence of a retardation or cessation of cartilage formation, and of an active destruction of cartilage. Administration of pituitary growth hormone reverses these regressive changes (1, 2, 4, 5). The initial effects of growthhormone treatment consist predominantly of chondrogenesis. Activation of osteogenesis follows later. The width of the cartilage disc increases during the first 6 to 8 days of treatment with growth hormone until the normal equilibrium between chondrogenesis and osteogenesis is reestablished. During this initial period of administration of growth hormone the resulting increase in width of the cartilage is, within certain limits of dosage, proportional to the quantity of growth hormone injected (5). Based on these phenomena, a new method was developed for the bioassay of...
Azabicyclo chemistry II. Synthesis of 1,5-methano-2,3,4,5-tetrahydro-1H-2-benzazepines. B-norbenzomorphans†

The syntheses of the B-norbenzomorphans, 1,5-methano-2,3,4,5-tetrahydro-1H-2-benzazepine (1a) and its N-methyl derivative (Ib) were accomplished. Phenylsuccinic anhydride (III) was cyclized to 3-carboxy-1-indanone (IVa), which was converted by the Arndt-Eistert method to the homologous methyl indanone-3-acetate (V). One experiment in the synthesis of V led to the by-products 3-carboxamido-1-indanone (IVd) and 3-(N-methylcarboxamido)-1-indanone (IVe), identified by physical and chemical means. Methyl 1-aminoindan-3-acetate (VII) was prepared by catalytic reduction of methyl indanone-3-acetate oxime (VI). Hydrolysis of VII afforded 1-aminoindan-3-acetic acid (VIII), which was cyclized with dicyclohexylcarbodiimide to 1,5-methano-2,3,4,5-tetrahydro-1H-2-benzazepin-3-one (IX). Reduction (lithium aluminum hydride) of IX gave amine Ia which was then methylated to Ib. The mass spectral fragmentation patterns of IX and Ia are discussed.
Flux flushing in superconducting niobium films

Flux trapping in superconducting devices has shown to be detrimental to the consistent operation of superconducting electronics (SCE). Approaches to improve reliability of SCE components have focused on introduction of flux trap regions and highly elaborate degaussing procedures. Nevertheless, a controlled and reproducible method to assure the elimination of trapped flux on SCE devices remains elusive. A substantial body of work on artificial defects utilizing the so called ratchet effect has demonstrate limited control of the magnetic vortices in niobium films. These early attempts to control the spurious vortices distribution have been limited to small geometrical regions having no practical effect on improving SCE devices operational parameters. In this paper, we report simulations and propose an improved method utilizing the ratchet effect that can be extended to physical sizes compatible to existing fabrication techniques of SCE devices.
Lagrangian simulations of unstable gravity-driven flow of fluids with variable density in randomly heterogeneous porous media

A new Lagrangian particle model based on smoothed particle hydrodynamics (SPH) is developed and used to simulate Darcy scale flow and transport in porous media. The method has excellent conservation properties and treats advection exactly. The Lagrangian method is used in stochastic analysis of miscible density-driven fluid flows. Results show that heterogeneity significantly increases dispersion and slows development of Rayleigh–Taylor instability. The presented numerical examples illustrate the advantages of Lagrangian methods for stochastic transport simulations.
Micromagnetic Barkhausen emissions in 2·25 wt% Cr–1 wt% Mo steel subjected to creep

Abstract Micromagnetic Barkhausen emissions have been measured from a number of specimens of Cr-Mo steel in order to study the effects of creep. Creep causes changes in the microstructure of materials as a result of exposure to a high temperature and pressure. Scanning electron micrographs showed that all the specimens were at an early stage of creep. The number density of cavities in specimens which were taken from the outer surface of the pipe was lower than in specimens taken from the inner surface, indicating lower creep on the outer surface. Rms and peak-to-peak voltages of Barkhausen emissions were found to increase from the outside to the inside of the pipe, indicating that these emissions increase with increasing level of creep. Segregation of impurities, which takes place during creep, was considered to be the primary cause of the increase in Barkhausen emission signals. A model has been developed which showed that Barkhausen voltage should increase up to a critical value of the number density of...
Asymmetry between flux penetration and flux expulsion in Tl-2212 superconductors

dc magnetic hysteresis as well as flux penetration and flux expulsion were investigated in Tl2−yBa2CaCu2O8−x polycrystals and monocrystals. All measurements were performed at 35 K and in the 0–5 T field range. Hysteresis measurements revealed an irreversibility field of about 2 T. Existing models predict identical field-cooled (fc) and zero-field-cooled (zfc) magnetizations and vanishing time dependence above this field. Although the identical fc and zfc magnetizations are in fact observed, the time dependence vanishes only for flux penetration after zero-field cooling; a remanence is preserved after field cooling and decays with a finite relaxation rate. Activation energies calculated on the basis of the thermal activation model display a pronounced field dependence, and arelower for flux penetration than for flux expulsion in high fields (H≥3 T) for all orientations. This behavior of extreme layered superconductors contradicts classical theoretical models and questions the original definition of the irreversibility line as well. All of our results are consistent with the recent theory of lock-in transition, and can be well interpreted by using those principles.
Social interaction among pleometrotic queens of Veromessor pergandei (Hymenoptera: Formicidae) during colony foundation

Queens of the pleometrotic seed-harvester ant Veromessor pergandei associate without respect to relatedness during colony foundation in laboratory choice tests. This species may be used as a test case for social competition where kin selection cannot occur. Co-founding queens contribute equally to the initial brood and exist without dominance prior to eclosion of their first workers. Before worker eclosion, claustral founding ants exhibit a closed-energy system. We argue that social competition cannot operate under such circumstances. Among pleometrotic, claustral founding ants, inter-queen aggression should not occur before worker emergence: this is verified for V. pergandei.
Design-based approach to ethics in computer-aided diagnosis

A design-based approach to ethical analysis examines how computer scientists, physicians and patients make and justify choices in designing, using and reacting to computer-aided diagnosis (CADx) systems. The basic hypothesis of this research is that values are embedded in CADx systems during all phases of their development, not just retrospectively imposed on them. This paper concentrates on the work of computer scientists and physicians as they attempt to resolve central technical questions in designing clinically functional CADx systems for lung cancer and breast cancer diagnosis. The work of Lo, Chan, Freedman, Lin, Wu and their colleagues provides the initial data on which this study is based. As these researchers seek to increase the rate of true positive classifications of detected abnormalities in chest radiographs and mammograms, they explore dimensions of the fundamental ethical principal of beneficence. The training of CADx systems demonstrates the key ethical dilemmas inherent in their current design.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Gran's titrations: Inherent errors in measuring the acidity of precipitation

Abstract Gran's titrations are commonly used to differentiate strong and weak acidity in precipitation. However, in the course of such titrations, dissociation of the weak organic acids found in precipitation causes overestimates of both strong and free acidity. In addition, the reaction of NH 4 + with OH − in the alkaline range of titrations causes overestimates of total acidity. Because of these effects, Gran's technique and related modifications have limited usefulness in characterizing the acidity of precipitation.
Inhibition of voltage-dependent Na+ and K+ currents by forskolin in nodes of Ranvier.

The effect of forskolin on voltage-activated Na+ and K+ currents in nodes of Ranvier from the toad, Bufo marinus, has been examined using the vaseline-gap voltageclamp technique. Peak Na+ currents (INa) were reduced by 35% and the rate of decline of Na+ current during continuous depolarization was accelerated following treatment with 450 μM forskolin. However, the voltage-dependence of steady-state inactivation as well as the rate of recovery from fast inactivation remained unchanged. Upon repetitive depolarization at 1–10 Hz, a further inhibition of INa (≈60%) was observed. This use-dependent or phasic inhibition recovers slowly at -80 mV (τ ≈ 13 s) and had a voltage-dependence like that of activation of the Na conductance. Near maximal steady-state phasic inhibition occurred with depolarizing pulse durations of only 4 ms, consistent with a direct involvement of the open Na+ channel in the blocking process. Inhibition of the delayed K+ current (IK) was characterized by a concentration-dependent reduction in steady-state current amplitude (IC50 ≈ 80 μM) and a concentration-independent acceleration of current inactivation. A similar inhibition of IK was obtained with 1,9-dideoxyforskolin, a homolog which does not activate adenylate cyclase (AC). The results suggest that the inhibition of IK and perhaps INa follows directly from drug binding and is not a consequence of AC activation.
Comprehensive Review of Morbidity and Mortality Trends for Rheumatic Fever, Streptococcal Disease, and Scarlet Fever: The Decline of Rheumatic Fever

This review of the medical literature reveals that the incidence of rheumatic fever has been declining for at least 150 years, preceding by many decades the use of penicillin as a preventive measure. Simultaneously, the prevalence of rheumatic heart disease has diminished. Streptococcal upper respiratory tract infections remain common but with reduced severity and fewer subsequent cases of rheumatic fever. Scarlet fever has become relatively benign, with low mortality. Whether recent sporadic outbreaks of rheumatic fever due to known rheumatogenic strains of group A streptococci will have a significant effect on morbidity and mortality trends remains to be seen. Relatively high rates of rheumatic fever and rheumatic heart disease in developing countries are difficult to evaluate because of irregularities in reporting and investigative procedures.
Ruptured Aneurysm at the Trunk of the Accessory Middle Cerebral Artery

¶ We present a 32-year-old woman with intracranial haemorrhage due to rupture of a saccular aneurysm arising from the trunk of an accessory middle cerebral artery. This is the first report of an aneurysm arising distally to the anomalous vessel's origin from the A1 segment of the anterior cerebral artery.
Spinal microglial proliferation is evident in a rat model of painful disc herniation both in the presence of behavioral hypersensitivity and following minocycline treatment sufficient to attenuate allodynia.

Although spinal glia acquire a reactive profile in radiculopathy, glial cell proliferation remains largely unstudied. This study investigated spinal glial proliferation in a model simulating painful disc herniation; the C7 nerve root underwent compression and chromic gut suture exposure or sham procedures. A subset of injured rats received minocycline injections prior to injury. Allodynia was assessed and bromodeoxyuridine (BrdU) was injected 2 hr before tissue harvest on day 1 or 3. Spinal cell proliferation and phenotype identification were assayed by fluorescent colabeling with antibodies to BrdU and either glial fibrillary acidic protein (astrocytes) or Iba1 (microglia). At day 1, ipsilateral allodynia was significantly increased (P < 0.001) for injury over sham. Minocycline treatment significantly decreased ipsilateral allodynia to sham levels at day 1 (P < 0.001). At day 3, ipsilateral allodynia remained and contralateral allodynia was also present for injury (P< 0.003) over sham. The number of BrdU-positive cells in the ipsilateral spinal dorsal horn at day 1 after injury was significantly elevated (P < 0.001) over sham. Approximately 70% of BrdU-positive cells labeled positively for Iba1; dividing microglia were significantly increased (P < 0.004) in the ipsilateral dorsal horn at day 1 following injury compared with sham. Spinal cellular proliferation after injury was not changed by minocycline injection. By day 3, the number of BrdU-positive cells had returned to sham levels bilaterally. Data indicate that spinal microglia proliferate after injury but that proliferation is not abolished by minocycline treatment that attenuates allodynia, indicating that spinal microglial proliferation may be related to injury and may not be linked to changes in sensory perception. © 2009 Wiley-Liss, Inc.
Parent-child physical play: The effects of sex and age of children and parents

Physical play is an important vehicle for differential socialization of boys and girls into appropriate sex roles. The aim of the study was to examine developmental changes in patterns of parent-child physical play as a function of the sex of parent and child. Three hundred ninety families with a total of 746 children ranging in age from under 1 year to 10 years were contacted by telephone and questioned about the frequency of physical-play interactions with their children. The results indicated that the strongest variable affecting the frequency of physical play was the age of the child. This developmental effect was curvilinear, with comparatively low levels prior to age one, a peak in the early childhood years, and the decline thereafter. Fathers tended to engage in more physical play than mothers. Effects of child sex were less evident, but tended to indicate that girls participated more often in nonstrenuous physical games with their parents, such as pattycake and being bounced on the parent's knee, while boys participated more often in activities such as wrestling and ball playing. There was a modest but significant tendency for older parents to engage less often in physical play with their children at each age level. The implications of parent-child physical play for sex role typing were noted.
Group velocity dispersion of CdSSe/ZnS core/shell colloidal quantum dots

We measure the group velocity dispersion (GVD) coefficient of two different sizes of commercially available CdSSe/ZnS semiconductor core/shell colloidal quantum dots in the ~700-900 nm range using white light Michelson interferometry.
Immunochemical Identification of Thyroglobulin Fragments Synthesized in Vitro by Bovine Thyroid Polyribosomes

14C-labeled proteins synthesized in vitro by bovine thyroid polyribosomes were studied by immunochemical methods with rabbit antithyroglobulin antiserum. Soluble proteins produced during incubation were partially precipitated by excess antithyroblobulin antibody plus anti-rabbit γ-globulin serum. The reaction could be partially blocked by altered thyroglobulin [sodium dodecyl sulfate-treated, trypsintreated or reduced and carboxymethylated (RCM)] and to a lesser extent by native thyroglobulin (TG). [14C]proteins solubilized from polyribosomes with 0.25% SDS were also partially precipitated by anti-TG serum, and precipitation was blocked only by altered TG, but the results were inconclusive due to extensive nonspecific coprecipitation. The anti-TG serum was found to contain at least 2 types of antibodies, one reacting with native TG and RCMTG and the other only with RCM-TG. These antibodies, isolated by adsorption with the appropriate antigen, were both capable of reacting with the newly synthesized [14C] ...