bluuebunny/crossref_metadata_2025 huggingface dataset:
Reconstitution of Retrograde Transport from the Golgi to the ER In Vitro
Authors: Spang Anne , Schekman Randy
Published: July 2002

Retrograde transport from the Golgi to the ER is an essential process. Resident ER proteins that escape the ER and proteins that cycle between the Golgi and the ER must be retrieved. The interdependence of anterograde and retrograde vesicle trafficking makes the dissection of both processes difficult in vivo. We have developed an in vitro system that measures the retrieval of a soluble reporter protein, the precursor of the yeast pheromone α-factor fused to a retrieval signal (HDEL) at its COOH terminus (Dean, N., and H.R.B Pelham. 1990. J. Cell Biol. 111:369–377). Retrieval depends on the HDEL sequence; the α-factor precursor, naturally lacking this sequence, is not retrieved. A full cycle of anterograde and retrograde transport requires a simple set of purified cytosolic proteins, including Sec18p, the Lma1p complex, Uso1p, coatomer, and Arf1p. Among the membrane-bound v-SNAP receptor (v-SNARE) proteins, Bos1p is required only for forward transport, Sec22p only for retrograde trafficking, and Bet1p is implicated in both avenues of transport. Putative retrograde carriers (COPI vesicles) generated from Golgi-enriched membranes contain v-SNAREs as well as Emp47p as cargo.
Nectin/PRR: An Immunoglobulin-like Cell Adhesion Molecule Recruited to Cadherin-based Adherens Junctions through Interaction with Afadin, a PDZ Domain–containing Protein
Authors: Takahashi Kenichi , Nakanishi Hiroyuki , Miyahara Masako , Mandai Kenji , Satoh Keiko , Satoh Ayako , Nishioka Hideo , Aoki Junken , Nomoto Akio , Mizoguchi Akira , Takai Yoshimi
Published: July 2002

We have isolated a novel actin filament–binding protein, named afadin, localized at cadherin-based cell–cell adherens junctions (AJs) in various tissues and cell lines. Afadin has one PDZ domain, three proline-rich regions, and one actin filament–binding domain. We found here that afadin directly interacted with a family of the immunoglobulin superfamily, which was isolated originally as the poliovirus receptor–related protein (PRR) family consisting of PRR1 and -2, and has been identified recently to be the alphaherpes virus receptor. PRR has a COOH-terminal consensus motif to which the PDZ domain of afadin binds. PRR and afadin were colocalized at cadherin-based cell–cell AJs in various tissues and cell lines. In E-cadherin–expressing EL cells, PRR was recruited to cadherin-based cell–cell AJs through interaction with afadin. PRR showed Ca2+-independent cell–cell adhesion activity. These results indicate that PRR is a cell–cell adhesion molecule of the immunoglobulin superfamily which is recruited to cadherin-based cell–cell AJs through interaction with afadin. We rename PRR as nectin (taken from the Latin word “necto” meaning “to connect”).
The Association between α4-Integrin, P-Selectin, and E-Selectin in an Allergic Model of Inflammation
Authors: Kanwar Samina , Bullard Daniel C. , Hickey Michael J. , Smith C. Wayne , Beaudet Arthur L. , Wolitzky Barry A. , Kubes Paul
Published: July 2002

In this study, we examined the relationship between the endothelial selectins (P-selectin and E-selectin) and whether they are critical for α4-integrin–dependent leukocyte recruitment in inflamed (late phase response), cremasteric postcapillary venules. Animals were systemically sensitized and 2 wk later challenged intrascrotally with chicken ovalbumin. Leukocyte rolling flux, adhesion, and emigration were assessed at baseline and 4 and 8 h postantigen challenge. There was a significant increase in leukocyte rolling flux, adhesion, and emigration in sensitized and challenged mice at both 4 and 8 h. At 8 h, the increase in leukocyte rolling flux was ∼50% inhibitable by an anti–α4-integrin antibody, 98% inhibitable by fucoidin (a selectin-binding carbohydrate), and 100% inhibitable by an anti–P-selectin antibody. P-selectin–deficient animals displayed no leukocyte rolling or adhesion at 8 h after challenge. However, at 8 h there were many emigrated leukocytes in the perivascular space suggesting P-selectin–independent rolling at an earlier time point. Indeed, at 4 h postantigen challenge in P-selectin–deficient mice, there was increased leukocyte rolling, adhesion, and emigration. The rolling in the P-selectin– deficient mice at 4 h was largely α4-integrin dependent. However, there was an essential E-selectin– dependent component inasmuch as an anti–E-selectin antibody completely reversed the rolling, and in E-selectin and P-selectin double deficient mice rolling, adhesion and emigration were completely absent. These results illustrate that P-selectin underlies all of the antigen-induced rolling with a brief transient contribution from E-selectin in the P-selectin–deficient animals. Finally, the antigen-induced α4-integrin–mediated leukocyte recruitment is entirely dependent upon endothelial selectins.
Identification of Lymphomyeloid Primitive Progenitor Cells in Fresh Human Cord Blood and in the Marrow of Nonobese Diabetic–Severe Combined Immunodeficient (NOD-SCID) Mice Transplanted with Human CD34+ Cord Blood Cells
Authors: Robin Catherine , Pflumio Françoise , Vainchenker William , Coulombel Laure
Published: July 2002

Transplantation of genetically marked donor cells in mice have unambiguously identified individual clones with full differentiative potential in all lymphoid and myeloid pathways. Such evidence has been lacking in humans because of limitations inherent to clonal stem cell assays. In this work, we used single cell cultures to show that human cord blood (CB) contains totipotent CD34+ cells capable of T, B, natural killer, and granulocytic cell differentiation. Single CD34+ CD19−Thy1+ (or CD38−) cells from fresh CB were first induced to proliferate and their progeny separately studied in mouse fetal thymic organotypic cultures (FTOCs) and cocultures on murine stromal feeder layers. 10% of the clones individually analyzed produced CD19+, CD56+, and CD15+ cells in stromal cocultures and CD4+CD8+ T cells in FTOCs, identifying totipotent progenitor cells. Furthermore, we showed that totipotent clones with similar lymphomyeloid potential are detected in the bone marrow of nonobese diabetic severe combined immunodeficient (NOD-SCID) mice transplanted 4 mo earlier with human CB CD34+ cells. These results provide the first direct demonstration that human CB contains totipotent lymphomyeloid progenitors and transplantable CD34+ cells with the ability to reconstitute, in the marrow of recipient mice, the hierarchy of hematopoietic compartments, including a compartment of functional totipotent cells. These experimental approaches can now be exploited to analyze mechanisms controlling the decisions of such primitive human progenitors and to design conditions for their ampification that can be helpful for therapeutic purposes.
The Structural Basis of Repertoire Shift in an Immune Response to Phosphocholine
Authors: Brown McKay , Schumacher Maria A. , Wiens Gregory D. , Brennan Richard G. , Rittenberg Marvin B.
Published: July 2002

The immune response to phosphocholine (PC)–protein is characterized by a shift in antibody repertoire as the response progresses. This change in expressed gene combinations is accompanied by a shift in fine specificity toward the carrier, resulting in high affinity to PC–protein. The somatically mutated memory hybridoma, M3C65, possesses high affinity for PC–protein and the phenyl-hapten analogue, p-nitrophenyl phosphocholine (NPPC). Affinity measurements using related PC–phenyl analogues, including peptides of varying lengths, demonstrate that carrier determinants contribute to binding affinity and that somatic mutations alter this recognition. The crystal structure of an M3C65–NPPC complex at 2.35-Å resolution allows evaluation of the three light chain mutations that confer high-affinity binding to NPPC. Only one of the mutations involves a contact residue, whereas the other two have indirect effects on the shape of the combining site. Comparison of the M3C65 structure to that of T15, an antibody dominating the primary response, provides clear structural evidence for the role of carrier determinants in promoting repertoire shift. These two antibodies express unrelated variable region heavy and light chain genes and represent a classic example of the effect of repertoire shift on maturation of the immune response.
Functionally Inert HIV-Specific Cytotoxic T Lymphocytes Do Not Play a Major Role in Chronically Infected Adults and Children
Authors: Goulder Philip J.R. , Tang Yanhua , Brander Christian , Betts Michael R. , Altfeld Marcus , Annamalai Ken , Trocha Alicja , He Suqin , Rosenberg Eric S. , Ogg Graham , O'Callaghan Christopher A. , Kalams Spyros A. , McKinney Ross E. , Mayer Kenneth , Koup Richard A. , Pelton Stephen I. , Burchett Sandra K. , McIntosh Kenneth , Walker Bruce D.
Published: July 2002

The highly sensitive quantitation of virus-specific CD8+ T cells using major histocompatibility complex–peptide tetramer assays has revealed higher levels of cytotoxic T lymphocytes (CTLs) in acute and chronic virus infections than were recognized previously. However, studies in lymphocytic choriomeningitis virus infection have shown that tetramer assays may include measurement of a substantial number of tetramer-binding cells that are functionally inert. Such phenotypically silent CTLs, which lack cytolytic function and do not produce interferon (IFN)-γ, have been hypothesized to explain the persistence of virus in the face of a quantitatively large immune response, particularly when CD4 help is impaired. In this study, we examined the role of functionally inert CTLs in chronic HIV infection. Subjects studied included children and adults (n = 42) whose viral loads ranged from <50 to >100,000 RNA copies/ml plasma. Tetramer assays were compared with three functional assays: enzyme-linked immunospot (Elispot), intracellular cytokine staining, and precursor frequency (limiting dilution assay [LDA]) cytotoxicity assays. Strong positive associations were observed between cell numbers derived by the Elispot and the tetramer assay (r = 0.90). An even stronger association between tetramer-derived numbers and intracellular cytokine staining for IFN-γ was present (r = 0.97). The majority (median 76%) of tetramer-binding cells were consistently detectable via intracellular IFN-γ cytokine staining. Furthermore, modifications to the LDA, using a low input cell number into each well, enabled LDAs to reach equivalence with the other methods of CTL enumeration. These data together show that functionally inert CTLs do not play a significant role in chronic pediatric or adult HIV infection.
T Cell Receptor Specificity Is Critical for the Development of Epidermal γδ T Cells
Authors: Ferrero Isabel , Wilson Anne , Beermann Friedrich , Held Werner , MacDonald H. Robson
Published: July 2002

A particular feature of γδ T cell biology is that cells expressing T cell receptor (TCR) using specific Vγ/Vδ segments are localized in distinct epithelial sites, e.g., in mouse epidermis nearly all γδ T cells express Vγ3/Vδ1. These cells, referred to as dendritic epidermal T cells (DETC) originate from fetal Vγ3+ thymocytes. The role of γδ TCR specificity in DETC's migration/localization to the skin has remained controversial. To address this issue we have generated transgenic (Tg) mice expressing a TCR δ chain (Vδ6.3-Dδ1-Dδ2-Jδ1-Cδ), which can pair with Vγ3 in fetal thymocytes but is not normally expressed by DETC. In wild-type (wt) Vδ6.3Tg mice DETC were present and virtually all of them express Vδ6.3. However, DETC were absent in TCR-δ−/− Vδ6.3Tg mice, despite the fact that Vδ6.3Tg γδ T cells were present in normal numbers in other lymphoid and nonlymphoid tissues. In wt Vδ6.3Tg mice, a high proportion of in-frame Vδ1 transcripts were found in DETC, suggesting that the expression of an endogenous TCR-δ (most probably Vδ1) was required for the development of Vδ6.3+ epidermal γδ T cells. Collectively our data demonstrate that TCR specificity is essential for the development of γδ T cells in the epidermis. Moreover, they show that the TCR-δ locus is not allelically excluded.
Tumor Growth Enhances Cross-Presentation Leading to Limited T Cell Activation without Tolerance
Authors: Nguyen Linh T. , Elford Alisha R. , Murakami Kiichi , Garza Kristine M. , Schoenberger Stephen P. , Odermatt Bernhard , Speiser Daniel E. , Ohashi Pamela S.
Published: July 2002

Using a tumor model of spontaneously arising insulinomas expressing a defined tumor-associated antigen, we investigated whether tumor growth promotes cross-presentation and tolerance of tumor-specific T cells. We found that an advanced tumor burden enhanced cross-presentation of tumor-associated antigens to high avidity tumor-specific T cells, inducing T cell proliferation and limited effector function in vivo. However, contrary to other models, tumor-specific T cells were not tolerized despite a high tumor burden. In fact, in tumor-bearing mice, persistence and responsiveness of adoptively transferred tumor-specific T cells were enhanced. Accordingly, a potent T cell–mediated antitumor response could be elicited by intravenous administration of tumor-derived peptide and agonistic anti-CD40 antibody or viral immunization and reimmunization. Thus, in this model, tumor growth promotes activation of high avidity tumor-specific T cells instead of tolerance. Therefore, the host remains responsive to T cell immunotherapy.
Cyclic GMP–gated Channels in a Sympathetic Neuron Cell Line
Authors: Thompson Stuart H.
Published: July 2002

The stimulation of IP3 production by muscarinic agonists causes both intracellular Ca2+ release and activation of a voltage-independent cation current in differentiated N1E-115 cells, a neuroblastoma cell line derived from mouse sympathetic ganglia. Earlier work showed that the membrane current requires an increase in 3′,5′-cyclic guanosine monophosphate (cGMP) produced through the NO-synthase/guanylyl cyclase cascade and suggested that the cells may express cyclic nucleotide–gated ion channels. This was tested using patch clamp methods. The membrane permeable cGMP analogue, 8-br-cGMP, activates Na+ permeable channels in cell attached patches. Single channel currents were recorded in excised patches bathed in symmetrical Na+ solutions. cGMP-dependent single channel activity consists of prolonged bursts of rapid openings and closings that continue without desensitization. The rate of occurrence of bursts as well as the burst length increase with cGMP concentration. The unitary conductance in symmetrical 160 mM Na+ is 47 pS and is independent of voltage in the range −50 to +50 mV. There is no apparent effect of voltage on opening probability. The dose response curve relating cGMP concentration to channel opening probability is fit by the Hill equation assuming an apparent KD of 10 μm and a Hill coefficient of 2. In contrast, cAMP failed to activate the channel at concentrations as high as 100 μm. Cyclic nucleotide gated (CNG) channels in N1E-115 cells share a number of properties with CNG channels in sensory receptors. Their presence in neuronal cells provides a mechanism by which activation of the NO/cGMP pathway by G-protein–coupled neurotransmitter receptors can directly modify Ca2+ influx and electrical excitability. In N1E-115 cells, Ca2+ entry by this pathway is necessary to refill the IP3-sensitive intracellular Ca2+ pool during repeated stimulation and CNG channels may play a similar role in other neurons.
Compound inversive congruential pseudorandom numbers: an average-case analysis
Authors: Eichenauer-Herrmann Jürgen , Emmerich Frank
Published: July 2002

The present paper deals with the compound (or generalized) inversive congruential method for generating uniform pseudorandom numbers, which has been introduced recently. Equidistribution and statistical independence properties of the generated sequences over parts of the period are studied based on the discrepancy of certain point sets. The main result is an upper bound for the average value of these discrepancies. The method of proof is based on estimates for exponential sums.
Pseudorandom vector generation by the compound inversive method
Authors: Emmerich Frank
Published: July 2002

Pseudorandom vectors are of importance for parallelized simulation methods. In this paper a detailed analysis of the compound inversive method for the generation of

k
k

-dimensional uniform pseudorandom vectors, a vector analog of the compound inversive method for pseudorandom number generation, is carried out. In particular, periodicity properties and statistical independence properties of the generated sequences are studied based on the discrete discrepancy of

s
s

-tuples of successive terms in the sequence. The results show that the generated sequences have attractive statistical independence properties for pseudorandom vectors of dimensions

k
≤
4

k\leq 4

.
Predicting insecticide resistance: mutagenesis, selection and response
Authors: McKenzie J. A. , Batterham P.
Published: July 2002

Strategies to manage resistance to a particular insecticide have usually been devised after resistance has evolved. If it were possible to predict likely resistance mechanisms to novel insecticides before they evolved in the field, it might be feasible to have programmes that manage susceptibility. With this approach in mind, single–gene variants of the Australian sheep blowfly,
Lucilia cuprina
, resistant to dieldrin, diazinon and malathion, were selected in the laboratory after mutagenesis of susceptible strains. The genetic and molecular bases of resistance in these variants were identical to those that had previously evolved in natural populations. Given this predictive capacity for known resistances, the approach was extended to anticipate possible mechanisms of resistance to cyromazine, an insecticide to which
L. cuprina
populations remain susceptible after almost 20 years of exposure. Analysis of the laboratory–generated resistant variants provides an explanation for this observation. The variants show low levels of resistance and a selective advantage over susceptibles for only a limited concentration range. These results are discussed in the context of the choice of insecticides for control purposes and of delivery strategies to minimize the evolution of resistance.
From genetics to pathology: tau and a–synuclein assemblies in neurodegenerative diseases
Authors: Goedert Michel , Grazia Spillantini Maria , Serpell Louise C. , Berriman John , Smith Michael J. , Jakes Ross , Anthony Crowther R.
Published: July 2002

The most common degenerative diseases of the human brain are characterized by the presence of abnormal filamentous inclusions in affected nerve cells and glial cells. These diseases can be grouped into two classes, based on the identity of the major proteinaceous components of the filamentous assemblies. The filaments are made of either the microtubule–associated protein tau or the protein α–synuclein. Importantly, the discovery of mutations in the tau gene in familial forms of frontotemporal dementia and of mutations in the α–synuclein gene in familial forms of Parkinson's disease has established that dysfunction of tau protein and α–synuclein can cause neurodegeneration.
Magnetic resonance imaging of microbubbles in a superheated emulsion chamber for brachytherapy dosimetry
Authors: Lamba Michael , Holland Scott K. , Elson Howard , d'Errico Francesco , Nath Ravinder
Published: July 2002

This paper describes development of magnetic resonance imaging (MRI) techniques for three‐dimensional (3D) imaging of a position‐sensitive detector for brachytherapy dosimetry. The detector is a 0.5 l chamber containing an emulsion of halocarbon‐115 droplets in a tissue‐equivalent glycerin‐based gel. The halocarbon droplets are highly superheated and expand into vapor microbubbles upon irradiation. Brachytherapy sources can be inserted into the superheated emulsion chamber to create distributions of bubbles. Three‐dimensional MRI of the chamber is then performed. A 3D gradient‐echo technique was optimized for spatial resolution and contrast between bubbles and gel. Susceptibility gradients at the interfaces between bubbles and gel are exploited to enhance contrast so microscopic bubbles can be imaged using relatively large voxel sizes. Three‐dimensional gradient‐echo images are obtained with an isotropic resolution of 300 μm over a field‐of‐view in an imaging time of 14 min. A post‐processing technique was developed to semi‐automatically segment the bubbles from the images and to assess dose distributions based on the measured bubble densities. Relative dose distributions are computed from MR images for a brachytherapy source and the results compare favorably to relative radial dose distributions calculated as recommended by Task Group 43 of the American Association of Physicists in Medicine.
Electron beam therapy with transverse magnetic fields
Authors: Nardi Eran , Barnea Gideon
Published: July 2002

Detailed Monte Carlo electron transport simulations were carried out for the purpose of investigating the possibility of improving electron dose distribution for therapeutic applications, by using transverse magnetic fields. The case studied here is that of a 15 MeV electron beam of 6 cm diameter. The electrons pass through 4 cm of field‐free tissue and a transverse magnetic field is applied for depth greater than 4 cm. A field of 3 T was found to improve the skin sparing factor by a factor of 2, when compared to field‐free irradiation. A field of 2 T could also have a significant effect although less pronounced than 3 T while, for the case at hand, a magnetic field of only 1 T is not effective. The results here include detailed energy deposition contours in three dimensions.
Anchoring effects in audiovisual speech perception
Authors: Shigeno Sumi
Published: July 2002

Two experiments were conducted to investigate whether or not anchoring and selective adaptation induce basically the same psychological effects. The purpose of the first experiment is to show how an audiovisual anchor modifies the perception of consonant–vowel (CV) syllables. The anchors were two purely acoustical, two purely optical, and three audiovisual CV syllables. The results were compared with those of audiovisual speech selective-adaptation experiments conducted by Roberts and Summerfield [Percept. Psychophys. 30, 309–314 (1981)] and Saldaña and Rosenblum [J. Acoust. Soc. Am. 95, 3658–3661 (1994)]. The audiovisual anchoring effects were found to be very similar to the audiovisual selective-adaptation effects, but the incompatible audiovisual anchor produced more auditory-based contrast than the purely acoustical anchor or the compatible audiovisual anchor. This difference in contrast had not been found in the previous selective-adaptation experiments. The second experiment was conducted to directly compare audiovisual anchoring and selective-adaptation effects under the same stimuli and with the same subjects. It was found that the compatible audiovisual syllable (AbVb) caused more contrast in selective adaptation than in anchoring, although the discrepant audiovisual syllable (AbVg) caused no difference between anchoring and selective adaptation. It was also found that the anchor AbVg caused more auditory-based contrast than the anchor AbVb. It is suggested that the mechanisms behind these results are different.
Shallow water beamforming with small aperture, horizontal, towed arrays
Authors: Wilson James H. , Veenhuis Robert S.
Published: July 2002

This paper shows that the performance of plane-wave beamformers is significantly degraded in shallow water for horizontal arrays, even for short aperture arrays. Horizontal towed arrays must have short apertures for practical reasons, and the plane-wave beamformer needs to be augmented to optimize performance in shallow water. Matched-field processing (MFP) is a beamforming technique which allows for the detection and localization of an acoustic source in range and depth using passive sonar. The performance of MFP to augment plane-wave beamforming in shallow water environments using a short aperture horizontal line array is investigated. It is realized that MFP performance is enhanced when vertical arrays are used in deep water, or large aperture horizontal arrays are available in shallow water. However, this paper addresses the realistic case of operational, tactical horizontal arrays which are practical to deploy in shallow water. This paper attempts to integrate inverse beamforming (IBF) [A. H. Nuttall and J. H. Wilson, J. Acoust. Soc. Am. 90, 2004–2019 (1991); J. H. Wilson, J. Acoust. Soc. Am. 98, 3250–3261 (1995)], a plane-wave beamformer, with MFP so that the strengths of each are utilized. Results of test cases using synthetic data are presented to evaluate the effects of frequency, bottom type, relative target bearing, and sound-speed profile on MFP and IBF performance. IBF consists of three algorithms: the Fourier integral method (FIM) beamformer; the eight nearest neighbor peak picker (ENNPP); and a sophisticated M of N tracker. It is shown that MFP performance is significantly better than plane-wave beamforming for higher frequencies, for more reflective bottom types in shallow water, and for relative target bearings away from the broadside beams. IBF, or plane-wave beamforming, performs well at very low frequencies (VLF), in mud/silt-clay bottoms, and at beams near broadside. It is also shown that the performance of any plane-wave beamformer, including IBF, is severely degraded in shallow water for relative bearings away from the broadside beams, particularly at higher frequencies. Finally, the MFP algorithm in conjunction with the ENNPP and M of N tracker are shown to perform well in the real, deep water ocean environment. No appropriate shallow water measured data is available to evaluate the integrated IBF/MFP algorithm in shallow water.
An efficient finite element scheme for solving the three-dimensional poroelasticity problem in acoustics
Authors: Panneton Raymond , Atalla Noureddine
Published: July 2002

In this paper, the finite element method (FEM) is used to solve the three-dimensional poroelasticity problem in acoustics based on the isotropic Biot–Allard theory. A displacement finite element model is derived using the Lagrangian approach together with an analogy with solid elements. From this model, it is seen that the “damping” and “stiffness” matrices of the poroelastic media are complex and frequency dependent. This leads to cumbersome calculations for large finite element models and spectral analyses. To overcome this difficulty, an efficient algorithm is proposed. It is based on low-frequency approximations of the frequency-dependent dissipation mechanisms in poroelastic media. This efficient algorithm allows the poroelastic materials to be modeled with classical FEM codes. Also, the acoustic–poroelastic and the poroelastic–poroelastic coupling conditions are presented. The proposed model is compared to existing literature for both two-dimensional and three-dimensional problems. Excellent comparisons prove both the accuracy and effectiveness of the proposed model and its coupling with acoustic elements. Finally, to show the usefulness of the proposed model, the edge effect on the absorption coefficient of a multilayered poroelastic material is presented. Results show that both analytical models based on laterally infinite poroelastic layers, and standing wave tube measurements may be misleading at low frequencies.
Tongue surface displacement during bilabial stops
Authors: Svirsky Mario A. , Stevens Kenneth N. , Matthies Melanie L. , Manzella Joyce , Perkell Joseph S. , Wilhelms-Tricarico Reiner
Published: July 2002

The goals of this study were to characterize tongue surface displacement during production of bilabial stops and to refine current estimates of vocal-tract wall impedance using direct measurements of displacement in the vocal tract during closure. In addition, evidence was obtained to test the competing claims of passive and active enlargement of the vocal tract during voicing. Tongue displacement was measured and tongue compliance was estimated in four subjects during production of /aba/ and /apa/. All subjects showed more tongue displacement during /aba/ than during /apa/, even though peak intraoral pressure is lower for /aba/. In consequence, compliance estimates were much higher for /aba/, ranging from 5.1 to 8.5×10−5 cm3/dyn. Compliance values for /apa/ ranged from 0.8 to 2.3×10−5 cm3/dyn for the tongue body, and 0.52×10−5 for the single tongue tip point that was measured. From combined analyses of tongue displacement and intraoral pressure waveforms for one subject, it was concluded that smaller tongue displacements for /p/ than for /b/ may be due to active stiffening of the tongue during /p/, or to intentional relaxation of tongue muscles during /b/ (in conjunction with active tongue displacement during /b/).
General theory for the spectral evolution of nonlinear Rayleigh waves
Authors: Knight E. Yu. , Hamilton M. F. , II’inskii Yu. A. , Zabolotskaya E. A.
Published: July 2002

The spectral theory developed by Zabolotskaya [J. Acoust. Soc. Am. 91, 2569–2575 (1992)] for nonlinear Rayleigh waves in isotropic solids is generalized to include fields with nonperiodic waveforms and nonplanar spatial dependencies. Model equations for cylindrical waves and diffracting beams that have been used in previous work, and which were obtained in an ad hoc manner, are derived here rigorously from first principles. The present theory for plane waves, which is derived using Hamiltonian formalism, is shown to be equivalent to the theory obtained by Parker [Int. J. Eng. Sci. 26, 59–75 (1988)], whose derivation is based on a different approach.
On coupled modes theory of two-dimensional wave motion in elastic waveguides with slowly varying parameters in curvilinear orthogonal coordinates
Authors: Galanenko V. B.
Published: July 2002

Coupled modes theory, as applied to 2-D wave propagation in range-dependent isotropic elastic waveguides in curvilinear orthogonal coordinates, is proposed. The model consists of one or more curvilinear layers with interfaces and outer boundaries departing slowly from the coordinate surfaces. The material parameters are supposed to be slowly dependent on the longitudinal coordinate. Four-dimensional vector-valued functions with the displacements, rotation, and divergence as the components are shown to be a convenient form of wave field description to extend the coupled modes theory from liquid to elastic waveguides. For this case, the cross section operator is defined and the generalized bi-orthogonality property of its eigenfunctions is established. Using the generalized bi-orthogonality, the coupling equations are derived. Wave propagation in a tube which narrows slowly to a conic rod and in a disk of radially dependent thickness are considered as the examples. The differences between the results obtained by the coupled modes theory and those the multiple-scales theory leads to are discussed. The theory modification for dealing with a cutoff phenomenon and the general algorithm of computation of the wave field excited by a point source are considered.
Influence of a toroidal bend on wind instrument tuning
Authors: Nederveen Cornelis J.
Published: July 2002

In a toroidal bend in a cylindrical wind instrument, with the same cross section as the cylindrical part, the inertance for longitudinal waves is reduced. This induces a change in the resonance frequency. The magnitude of this change depends on the length and the sharpness of the bend and on its position in the sound field. A transition to a cylinder gives an additional inertance correction. The present study compares known results from literature and adds new facts, employing analytical and numerical methods. Possible causes of the discrepancies between measurements and theory as reported in the literature are considered. The theory was verified by measurements on some toroidal bends in between cylindrical tube pieces. Corrections were applied for diameter differences between the torus and the rest of the pipe system. Within experimental uncertainty, a satisfactory correspondence with theory was found. The results obtained in the present study determine which diameter reduction in the bend can compensate the effects of the bend on the tuning.
Simple methods of estimating source levels and locations of marine animal sounds
Authors: Cato Douglas H.
Published: July 2002

This paper describes three relatively simple methods of estimating source levels of marine animal sounds by estimating the source distance acoustically, using one or two hydrophones. The methods are logistically simpler than using arrays of hydrophones of known positions but are accurate over a smaller range of distances. One method makes use of the differences in the arrival times and levels of the signals received at two hydrophones from the same sound emission. No knowledge of the positions of the hydrophones is required, however, if these are known the position of the source can be determined, with left–right ambiguity. The second method uses the difference in received levels only, but requires the hydrophone spacing to be known. Adequate accuracy requires the source to be significantly closer to one hydrophone than to the other. Third, if the direct and surface reflected arrivals can be separated, the source level can be determined with a single hydrophone. The methods require accurately calibrated hydrophones.
Acoustics of opera houses: A cultural heritage
Authors: Fausti Patrizio , Pompoli Roberto , Prodi Nicola
Published: July 2002

An important part of contemporary Italian musical culture has developed inside historical opera houses. An outstanding opera repertory was especially conceived to match these places, both from the architectural and the acoustical points of view. But, while extensive attention is devoted to architectural and historical aspects, the acoustical characteristics of an opera house, that is, the set of listening attributes which make such a place unique among all spaces for music, are still nowadays hardly recognized as being paramount. In fact they can be rightly considered a relevant cultural heritage in Italy and can thus be called acoustical heritage. This new kind of heritage calls for accurate study and attention, both from the scientific and social points of view. To preserve the heritage for future generations, it is necessary to know it precisely and to elaborate means of accurate description. A project with the participation of international specialists has been established to agree on a standardized procedure for acoustic measurements specific to Italian historical opera houses in order to investigate the pecularity of these places. The aim of the project is to give a state-of-the-art acoustic documentation fo some theaters with the possibility of later applying up-to-date acoustical analysis.
Statistics of Random Media
Authors: Frisch H. L.
Published: July 2002

We define random media as certain stochastic processes and consider briefly the question of whether a consistent subfamily of distribution functions can be extended to obtain a stochastic process characterizing a random medium. We define and discuss the “statistical geometry” of “two-phase” random media and “symmetric” random media. We also review certain aspects of random subdivisions of space into crystals, radiation scattering from particulate assemblies such as random packings of rigid spheres and percolation processes in random crystals and random networks.
Stress Relaxation of Nonlinear Viscoelastic Material under Uniaxial Strain
Authors: Lai J. S. Y. , Findley W. N.
Published: July 2002

A constitutive equation using a multiple integral functional relationship for stress relaxation of nonlinear viscoelastic material has been investigated for uniaxial stress. The first three integrals were retained and the relaxational functions for constant strain were determined from experiments on polyurethane at constant strain. Using this information the behavior during a multistep strain history was computed using two approximate procedures (a) assuming a product form for the kernel function and (b) employing a modified superposition principle. The latter yielded the more accurate description, although both gave good results.
Rheological differences among liquid-crystalline polymers. I. The first and second normal stress differences of PBG solutions
Authors: Baek S.-G. , Magda J. J. , Larson R. G.
Published: July 2002

In this paper and its sequel, we attempt to understand the rheological differences between lyotropic and thermotropic liquid-crystalline polymers by contrasting the rheology of three different liquid-crystalline polymers at concentrations ranging from moderate (12%–30%) to highly concentrated (30%–50%) to densely packed (50%–100%). This first paper presents the steady-state first and second normal stress differences N1 and N2 as functions of the shear rate γ̇ for solutions of poly(γ-benzyl-glutamate) with molecular weight 238 000, in the solvent metacresol, at concentrations C ranging from 12.5% to 40% by weight. Predictions of N1 and N2 for this range of concentration are obtained from the Doi molecular theory for rod-like nematics, using both an approximate, and a nearly exact, method for solving the Doi equation. The predictions of N1, and to a lesser extent N2, agree qualitatively with measured values for all concentrations. In particular, the range of shear rates over which N1 is negative shifts upward with increasing concentration: if we define γ̇max as the shear rate for which N1 reaches a positive maximum value N1max, then we find that theory agrees with experiment in that both γ̇max and N1max increase monotonically with concentration C. These increases occur because the strength of the nematic interaction increases with C, which implies that for high concentrations, N1 becomes negative only at high-shear rates.
Arginyl‐tRNA‐protein transferase 1 (ATE1) promotes melanoma cell growth and migration
Authors: Lazar Ikrame , Fabre Bertrand , Feng Yongmei , Khateb Ali , Frit Philippe , Kashina Anna , Zhang Tongwu , Avitan‐Hersh Emily , Kim Hyungsoo , Brown Kevin , Topisirovic Ivan , Ronai Ze’ev A.
Published: May 2022

Arginyl‐tRNA‐protein transferase 1 (ATE1) catalyses N‐terminal protein arginylation, a post‐translational modification implicated in cell migration, invasion and the cellular stress response. Herein, we report that ATE1 is overexpressed in NRAS‐mutant melanomas, while it is downregulated in BRAF‐mutant melanomas. ATE1 expression was higher in metastatic tumours, compared with primary tumours. Consistent with these findings, ATE1 depletion reduced melanoma cell viability, migration and colony formation. Reduced ATE1 expression also affected cell responses to mTOR and MEK inhibitors and to serum deprivation. Among putative ATE1 substrates is the tumour suppressor AXIN1, pointing to the possibility that ATE1 may fine‐tune AXIN1 function in melanoma. Our findings highlight an unexpected role for ATE1 in melanoma cell aggressiveness and suggest that ATE1 constitutes a potential new therapeutic target.
The impacts of management interventions on the sociality of African lions (Panthera leo): Implications for lion conservation
Authors: McEvoy Orla K. , Ferreira Sam M. , Parker Dan M.
Published: May 2022

African lion (Panthera leo) populations normally consist of several neighbouring prides and multiple adult males or groups of males that interact competitively. In large, open systems, cub defence from infanticidal males and territory defence drive group living in lions. However, in smaller (<1000 km2), fenced wildlife reserves, opportunities for natural immigration and emigration are limited which means that the evolutionary drivers of lion sociality may collapse.

Here, we use lion behavioural data collected from 16 wildlife reserves across South Africa to test how management‐induced ecological conditions alter lion social dynamics.

The number of lionesses observed together was best predicted by pride size, prey biomass and biome. Lionesses were less likely to group together as pride size increased, but more likely to group together as prey biomass and habitat productivity increased. In addition, adult males were observed more frequently with prides that had young (<12 months) cubs in reserves that had unfamiliar adult males present compared to reserves without any unfamiliar adult males.

Our results demonstrate how intraspecific competition between lions drives their sociality, and this may break down in small, fenced wildlife reserves where lions are actively managed. Although small, fenced reserves in South Africa have made a significant contribution to increasing lion numbers on the continent, our work highlights several important ecological implications of active lion management. For wildlife managers, mimicking the outcomes of different levels of intraspecific competition is likely a critical management tool for the persistence of lions in small reserves.
Coaching approaches for a lost sense of self – hunt it down or let it be?
Authors: Dodwell Tessa
Published: May 2022

This article uses Stevens’s (2002) five lenses (biological, experimentalist, social constructivist, psychodynamic and experiential) and Bachkirova’s (2011) three stories of the self (self as an operator, an evolved self and no self) to describe different manifestations and interpretations of a lost sense of self. Using a developmental coaching approach, the article then explores three key considerations when coaching a lost sense of self. Firstly, the origin of the loss – how the loss was first sensed by the client. Secondly, the importance of understanding client self-concept is explored in two parts. Initially, understanding of their self-construction (unitary stable self, dynamic self, multiple selves and no self) and next their ego development stage (unformed, formed and reformed). Self-concept is likely to inform client response to their lost sense of self but also inform the type of coaching techniques that might be most appropriate. Finally, the coach perspective is considered. Coaches are encouraged to be aware of their own self-concept and how it might impact their approach. This article concludes that a blend of all these factors will determine whether a lost sense of self is hunted down or simply let be.
PEAK: A model for use within performance coaching
Authors: O’Moore Garret
Published: May 2022

This paper introduces ‘PEAK’, a model suitable for use within performance coaching. PEAK is an acronym formed from the four interacting domains that are considered to underpin performance; Purpose, Engagement, Ability, and Know-how. The aim is to present an overview of the model and the theory that underpins it as well as providing a brief example of the model in practise.
The application of the responsibility pie technique in coaching
Authors: O’Moore Garret
Published: May 2022

This article focuses on the ‘responsibility pie’ technique which can help clients consider the degree to which they are personally responsible for a difficult situation or event and take appropriate action.
MI techniques: The Typical Day
Authors: Passmore Jonathan
Published: May 2022

This article is the third in the techniques series which are drawn from the motivational interviewing approach. In the previous papers I summarised briefly the principles of motivational Interviewing (Passmore, 2011a) and in the techniques section offered a perspective on the application of reflective listening (Passmore, 2011b) and ‘the balance sheet technique (Passmore, 2011c). In this paper I will briefly review a technique called ‘A Typical Day’. Typical Day is a useful technique or more rightly an exercise, which is used at the start of a coaching conversation to encourage the coachee to talk about the key issue. It offers the coach the opportunity to demonstrate listening and empathy while also gaining a detailed understanding of the issue.
MI techniques: Agenda Mapping
Authors: Passmore Jonathan
Published: May 2022

This article is the fifth in a series for The Coaching Psychologist which is drawn from the Motivational Interviewing (MI) approach. In the previous papers I have summarised briefly the principles of MI (Passmore, 2011a). In four further papers for the techniques section I have offered a perspective on the application of ‘Reflective listening’ (Passmore 2011b), ‘The balance sheet technique’ (Passmore, 2011c), a ‘Typical day’ (Passmore, 2012a) and ‘Recognising change talk’ (Passmore 2012b). In this paper I will briefly review a ‘technique’ which is at the start of the MI process and while not formalised in much of the coaching literature is a common practice among coaching psychologists when using Cognitive Behavioural Coaching and behavioural-based approaches such as GROW. This technique, Agenda Mapping, aims to help the coach and coachee to agree the focus for the coaching conversation.
Is it time to REGROW the GROW model? Issues related to teaching coaching session structures
Authors: Grant Anthony M.
Published: May 2022

Although models of how to structure coaching sessions are widely taught in coach training programmes there has been little or no debate in the literature about the use of session structures, the teaching of them, or the relative advantages or disadvantage of different specific session structure frameworks, and there have been few links drawn between the theoretical underpinnings of coaching and session structures. This paper explores these issues, giving examples of session structures and presents some frameworks that may help guide the categorisation and teaching of these structures. A variation of the well-known GROW model is presented; the RE-GROW model which explicitly links coaching session structure to self-regulation theory.
Steps to Solutions: A process for putting solution-focused coaching principles into practice
Authors: Grant Anthony M.
Published: May 2022

Solution-focused coaching is increasingly used by leaders, managers, and human resource professionals as well as professional coaches. Although the principles underpinning solution-focused coaching are simple, some people find it difficult to put those principles into practice in a systematic manner – simple is not the same as easy. Although there are a number of models designed to help guide solution-focused coaching conversations, to date little attention has been paid to the process of teaching solution-focused coaching skills. This is especially the case when teaching solution-focused coaching skills in organisational settings where time is limited and where individuals, particularly those with high levels of technical expertise may find it challenging to switch roles from manager to leader-as-coach. This article gives a short overview of key solution-focused principles, discusses some of the common challenges facing leaders, managers, consultants and other professionals as they learn solution-focused coaching approaches, and presents a simple step-by-step structured process for teaching, learning and practising solution-focused coaching.
Narrative coaching – Part 4: Redesigning the GROW model as the 4th generation coaching for people and the planet
Authors: Law Ho
Published: May 2022

This paper reflects and reviews the formulation of the GROW model in relation to narrative coaching in response to the climate change crisis, the socio-cultural and technological paradigms. It proposes a new coaching model by redesigning the GROW process and integrating it with narrative coaching process. It argues that the new model called ROGWin can be regarded as the 4th generation coaching (4GC) in terms of the evolution of coaching psychology as a professional discipline. Its implications to future research, practice including the technological impact such as artificial intelligence (AI) and wider role in the world and environment are discussed.

Keywords:

AI; climate change; fourth generation coaching; 4GC; coaching psychology; GROW; environment.
Positive Psychology Techniques – Active Constructive Responding
Authors: Passmore Jonathan , Oades Lindsay G.
Published: May 2022

This short article focuses on the skill of Active Constructive Responding, a technique used when working within a positive psychology coaching framework. The paper offers a table that describes the behaviours, cognitions and emotions at six levels of listening. It offers a way to combine active listening with positive feedback responses to help demonstrate empathy and foster positive self-regard.