cssi/SciSciGPT-SciSciNet huggingface dataset:
Spin dynamics in the mixed valence alloy Ce 1-x Th x

Temperature-dependent neutron-scattering experiments have been performed on a polycrystalline sample of ${\mathrm{Ce}}_{0.74}$${\mathrm{Th}}_{0.26}$ which undergoes a first-order $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\alpha}$ valence transition at ${T}_{V}\ensuremath{\sim}150$ K. By a measurement of the temperature dependence of the lattice parameter and use of V\'egard's law, we estimate the temperature behavior of the valence of Ce. The $Q$ dependence of the magnetic scattering is found to follow the form factor of the ${\mathrm{Ce}}^{3+}$ ion surprisingly well. In the inelastic scans, particular attention has been paid to the subtraction of the phonon background via an inelastic study of an identically sized and shaped sample of the nonmagnetic material ${\mathrm{La}}_{0.73}$${\mathrm{Th}}_{0.27}$. The corrected ${\mathrm{Ce}}_{0.74}$${\mathrm{Th}}_{0.26}$ spectra have then been expressed in the form of the imaginary part of the susceptibility ${\ensuremath{\chi}}^{\ensuremath{'}\ensuremath{'}}(\stackrel{\ensuremath{\rightarrow}}{\mathrm{Q}},\ensuremath{\omega})$. The $\ensuremath{\gamma}$-phase dynamic susceptibility is a broad feature with significant intensity extending beyond 70.0 meV (the limit of our measurement) with a peak near \ensuremath{\sim}20.0 meV. On cooling below ${T}_{V}$ the susceptibility decreases in magnitude and broadens such that the peak is beyond 70.0 meV. These results are compared with the macroscopic magnetic susceptibility which exhibits behavior similar to $\ensuremath{\chi}(\stackrel{\ensuremath{\rightarrow}}{\mathrm{Q}})$ obtained from ${\ensuremath{\chi}}^{\ensuremath{'}\ensuremath{'}}(\stackrel{\ensuremath{\rightarrow}}{\mathrm{Q}},\ensuremath{\omega})$ by a Kramers-Kronig analysis.
Consonant and vowel perception and production: Early English-French bilinguals and English monolinguals

This study is a comparative analysis of the English phonetic systems of 10 fluent adult English-French bilinguals who acquired their two languages prior to age 8 and who were English-dominant, and of 10 adult English monolinguals. The objective of the study was to determine whether or not early English-dominant bilinguals perceive and produce speech as English monolinguals do. Discrimination and identification tests of synthetic /d−t/ and /i−I/ continua and speech production tests revealed that the bilinguals’ discrimination and production of /d/ and /t/ and their production of /I/ did not differ significantly from the monolinguals’. However, the bilinguals’ identification of /d−t/ and /i−I/ and one aspect of their production of /i/ did differ significantly from that of the monolinguals. The present results indicate that early bilingualism can yield monolingual-like performance in at least one of the bilinguals’ languages, but only with respect to certain aspects of the phonetic system. These findings are viewed in light of sound-class distinctions, the perception-production dichotomy, and bilingual phonetic transfer and restructuring.
Updating reviews: the experience of the Cochrane Neonatal Review Group.

Summary Maintaining updated systematic reviews is one of the key goals of the Cochrane Collaboration. Reviews are meant to be updated at an interval of no more than 2 years. The Cochrane Neonatal Review (CNRG) is one of the most productive contributors to the Cochrane Collaboration. However, this means that the CNRG now has a more urgent need to address the issue of review updates. In order to do so, the CNRG has sought methods to prioritise and facilitate the review process.
The M2/Alternatively Activated Macrophage Phenotype Correlates with Aggressive Histopathologic Features and Poor Clinical Outcome in Early Stage Breast Cancer.

Background: Angiogenesis is critical for breast cancer progression. Within tumors, non-neoplastic cells assist tumor growth by producing growth factors and pro-angiogenic cytokines. Studies have demonstrated that tumor-associated macrophages (TAMs) are recruited to tumors before malignant conversion and are essential for promoting angiogenesis. We sought to study the role that macrophage phenotype—classically activated (M1) and alternatively activated (M2)—plays in the subsequent activation of the angiogenic pathway, with the goal of understanding the mechanisms underlying angiogenesis in the different molecular subtypes of breast cancer.Methods: 128 matching breast tumors, DCIS and normal tissues were obtained from the University of Chicago Breast Cancer SPORE tissue bank under IRB approved protocols. Tissue microarrays were constructed and molecular subtype was assigned based on immunohistochemical (IHC) staining into the following groups: luminal A (ER+, PR+, HER2-), luminal B (ER+, HER2+ or ER+, PR-), HER2-like (ER-, HER2+) and basal-like (ER-, HER2-, EGFR+ and/or CK5/6+). Macrophage phenotype was determined using double staining with CD68/CD163 (M2) and CD68/CD80 (M1). Microvessel density (MVD) was measured by IHC staining using anti-CD34. Staining quantification was performed independently by two pathologists. To control for intra-individual correlation, linear mixed-effects models were used to compare differences in % of M1 and M2 with disease progression. To evaluate the association of MVD with % of M1 and M2, bivariate plots were generated and Pearson9s correlation coefficients were calculated. Spearman9s correlation coefficients were used for the correlation between macrophage phenotype and tumor stage and grade. The Kaplan-Meier method was used to calculate overall survival.Results: Of the tumors studied, 88% were stage I-II. 17% were grade 1, 39% grade 2 and 44% grade 3. 70 were luminal A, 36 basal-like, 9 HER2-like and 6 luminal B. The ratio of M2:M1 increased with disease progression from normal breast to DCIS to invasive cancer (p Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 107.
de Haas—van Alphen Study of Coherent Magnetic Breakdown in Magnesium

Studies of the de Haas---van Alphen spectra arising from the two-dimensional lattice of magnetic-breakdown---coupled orbits in magnesium contain spectral features which disagree qualitatively with the accepted theory of Falicov and Stachowiak. Their theory, which was thought to be equivalent to Pippard's theory for the magnetic band structure, is shown to be inequivalent.
A non-Gaussian renormalization group fixed point for hierarchical scalar lattice field theories

A rigorous method is developed to handle the “large field problems” in the Wilson-Kadanoff renormalization group approach to critical lattice systems of unbounded spins. We use this method to study in a hierarchical approximation the non-Gaussian renormalization group fixed point which governs the infrared behaviour of critical lattice field theories in three dimensions. The method is an improvement of the analyticity techniques of Gawedzki and Kupiainen: using Borel summation techniques we are able to incorporate the “large field region” into the “perturbative region” so that the theory is completely described in terms of convergent expansions.
2-D FFT algorithm by matrix factorization in a 2-D space

A new 2-D FFT algorithm is described. This algorithm applies a 2-D matrix factorization technique in a 2-D space and offers a way to do 2-D FFT in both dimensions simultaneously. The computation is greatly reduced compared to traditional algorithms. This will improve the realization of a 2-D FFT on any kind of computer. However its good parallelism will especially benefit an implementation on a computer with hypercube architecture. A good arrangement of parallel processors will save a great deal of running time. Furthermore this algorithm can be extended toM-D cases forM>2.
The helplessness–hopelessness theory and daily mood experience: An idiographic and cross-situational perspective.

The experience sampling method was used to examine the helplessness-hopelessness theory as a model of normal mood fluctuations. Ninety-one participants were signaled 5 times daily for a 1-week period to provide reports of negative events, specific cognitions, and anxiety and depression. Attributional and perception of control styles did not explain anxious or depressed moods, but they were predictive of the causal attributions and perceptions of control made across diverse environmental contexts. Furthermore, idiographic analyses demonstrated that specific causal attributions about negative events explained fluctuations in depressed mood within the flow of daily life. In contrast to the theory, perceptions of event controllability were not related to fluctuations in anxious mood or to the later formulation of causal attributions. Implications for understanding normal mood experience and the helplessness-hopelessness theory are discussed.
A (d, k, c)=(0, 3, 5/2) rate 8/10 modulation code

A DC-free modulation code with parameters (d, k c)=(0, 3, 5/2) is presented. A state-machine encoder converts 8-b blocks of user data to 10-b blocks of channel sequences in NRZI (nonreturn-to-zero invert) notation through state-dependent tables, which are decoded in 10-b blocks through a single table in a stateless, independent block fashion. The underlying constraint graph for the code is presented, and the extraction of practical 8/10 codes from the constraint graph is shown. Coding tables for a particular extraction are discussed, and the code is compared to similarly constrained modulation codes. >
Analysis of a microstrip step discontinuity fabricated on a metal‐insulator‐semiconductor (MIS) substrate

A space-domain coupled integral equation analysis is used to compute the two-dimensional surface current distribution on a basic microstrip step discontinuity fabricated on an MIS substrate. The two-port scattering parameters are computed from the surface current and their accuracy is verified through comparison with a measured data. © 1992 John Wiley & Sons, Inc.
Nardilysin cleaves peptides at monobasic sites.

Nardilysin (N-arginine dibasic convertase, EC 3.4.24.61) was first identified on the basis of its ability to cleave peptides containing an arginine dibasic pair, i.e., Arg−Arg or Arg−Lys. However, it was observed that an aromatic residue adjacent to the dibasic pair (i.e., Phe−Arg−Lys) could alter the cleavage site. In this study we determined whether nardilysin can cleave peptides at a single basic residue. Nardilysin cleaves β-endorphin at the monobasic site, Phe17−Lys18, with a kcat/Km of 2 × 108 M-1 min-1. This can be compared to a kcat/Km of 8.5 × 108 M-1 min-1 for cleavage between a dibasic pair in dynorphin B-13. Nardilysin also cleaves calcitonin at His−Arg and somatostatin-14 at Cys−Lys. We examined the hydrolysis of fluorogenic peptides based on the β-endorphin 12−24 sequence, Abz-T-P-L-V-T-L-X1-X2-N-A-I-I-K-Q-EDDnp. Nardilysin hydrolyzes the peptides when X1−X2 = F−K, F−R, W−K, M−K, Y−K, and L−K. The kinetics of cleavage at F−K and F−R are similar; however, K−F is not hydrolyzed. Nardilysin cle...
Surface deactivation of porous glass membranes.

Protein solutions exposed to porous glass membranes are rapidly depleted of protein. The proteins do not migrate through the membrane, but become trapped at the channel walls. Surface deactivation of porous glass can be accomplished by treatment with methyl trimethoxysilane or γ-aminopropyl triethoxysilane. Bacitracin slowly transferred through a surface deactivated porous glass membrane.
Characterization of optical components for use in harsh environments

The characterization of mounted and/or bonded optical assemblies for survivability in harsh environments is crucial for the development of robust laser-optical firing systems. Customized mounts, bonded assemblies and packaging strategies were utilized for each of the laser resonator optics with the goal of developing and fielding a reliable initiation system for use in extreme conditions. Specific components were selected for initial testing based on past experience, material properties and optical construction. Shock, vibration and temperature testing was performed on three mounted optical components; polarizing cube beam splitters, Q-switch assemblies and xenon flashlamps. Previously, flashlamps of a solder-sealed construction type were successfully tested and characterized. This test regiment characterized the more fragile glass-to-metal seal constructed flashlamps. Components were shock-tested to a maximum impulse level of 5700 G's with a 1.1 millisecond long pulse. Vibration tests were performed to a maximum level of 15.5 grms for forty seconds in each of three axes. During each test, components were functionally tested and visually inspected at a specified point to verify survival. Temperature tests were performed over a range extending from a maximum of 75 degrees C to a minimum of -55 degrees C, allowing for a two hour soak at each temperature set point. Experimental results obtained from these tests will be discussed as will their impact on future component mounting strategies.
Technical Note The b-function and variable stream buffer mapping: a note on ‘A GIS method for riparian water quality buffer generation’

Abstract Mapping variable stream buffers in a vector environment in which buffer width values are delineated often yields inaccurate results. Possible vector solutions are either ineffective or inefficient, An alternate raster approach is presented here in which a buffer effectiveness-achievement function (b-function) is introduced to map desirable buffer zones at an individual cell level based upon areal differentiations in physical and ecological conditions. The implementation of b-function is made feasible by a GIS procedure devised in this article. This tested method can be extended to a variety of variable buffer studies, such as visual buffers, noise buffers, greenways, and urban natural buffers. ‘A robe can never be made of the fur from one fox's axillae’ (A Chinese idiom).
Mass aggregation of diatom blooms: Insights from a mesocosm study

While the aggregation and mass settlement of diatoms at the termination of blooms results in significant export of carbon from the surface ocean, the mechanisms of bloom aggregation have been poorly understood. The aggregation of a multispecies diatom bloom was investigated under controlled conditions in a 1200 liter, nutrient-enriched, laboratory mesocosm in order to elucidate the parameters sufficient to accurately predict bloom aggregation. A diverse bloom of diatoms dominated by several species of Chaetoceros and Thalassiosira progressed through a classic pattern of exponential, stationary, and senescent phases in the mesocosm. Aggregates larger than 0.5 mm became detectable on the eighth day after inoculation, and aggregates >1 mm increased exponentially from Day 10 onward producing the appearance of a mass aggregation event late on Day 10. The bloom aggregated sequentially with Thalassiosira dominating early aggregates and Chaetoceros dominating later ones. Chaetoceros resting spores formed only in aggregates. Aggregation was not linked to nutrient depletion or to the physiological state of the cells since the onset of aggregation and the mass aggregation event occurred 1 to 3 days prior to nutrient depletion and while carbon:nitrogen ratios of cells were still very low and growth rates high. Moreover, visible aggregates did not form in the mesocosm until cell abundances were considerably higher than abundances observed to aggregate in nature, suggesting that aggregation was not strongly linked to phytoplankton cell concentration. Complementary studies in this volume clarify the role of non-phytoplankton particles in aggregation of the mesocosm bloom. The mesocosm approach proved highly effective in producing an aggregating diatom bloom under controlled conditions.
Assessment and Instructional Decision-Making Practices of Preschool Teachers of Handicapped Children

Assessment and instructional decision-making practices were documented for a national sample of teachers serving handicapped preschool children. All had been nominated as “good” teachers. Surveys of 60 teachers and in-depth interviews of an additional 10 revealed that evaluation and monitoring procedures are not used systematically or regularly. Behavioral observations were the most widely used single source of information for making instructional decisions. Teacher self-reports indicated that criterion-referenced measures provided the information used most often in developing IEPs and in monitoring student progress, while progress on previous IEP objectives was used most often in changing IEPs. This sample of teachers of handicapped preschool children did not regularly or systematically engage in direct and continuous monitoring of pupil progress.
Effects of Turbulence on Yolk‐Sac Larvae of Paddlefish

Abstract A laboratory experiment was designed to test the effect of turbulence on mortality of yolk-sac larvae of paddlefish Polyodon spathula. High turbulence (6,320 dynes˙cm-2) resulted in larval mortality of 87 and 80% in frequent (one event per hour) and infrequent (one event every 3 h) treatments, respectively. Larvae exposed to low turbulence (1,838 dynes˙cm-2) suffered mortality of only 3 and 13% in the frequent and infrequent treatment groups, respectively. Frequency of events was not as important as intensity of turbulence in causing mortality.
Functional complementation of glycoprotein 72 in a Trypanosoma cruzi glycoprotein 72 null mutant

Abstract To investigate the role of a developmentally regulated 72-kDa surface antigen of Trypanosoma cruzi (GP72), a GP72 null mutant was previously produced [Cooper et al., 1993, J. Cell Biol. 122, 149–156]. Abnormal morphology of epimastigote and metacyclic trypomastigote stages of the GP72 null mutant suggested that GP72 is associated with flagellum-cell adhesion [Cooper et al., 1993, J. Cell Biol. 122, 149-156; De Jesus et al., J. Cell Sci., in preau]. In the present study, functional complementation of the GP72 null mutant was accomplished by transformation with two independent episomal vectors expressing GP72 and phleomycin or tunicamycin resistance genes. A correlation between gene copy number, RNA level, expression of GP72, and morphological phenotypes was demonstrated. Disparities were observed between gene copy number and RNA level and between the apparent level of GP72 polypeptide and the carbohydrate epitope recognized by monoclonal antibody WIC29.26. Restoration of morphology reflects recovery of the carbohydrate epitope, suggesting that the novel glycosylation of GP72 is the limiting step in the expression of its function.
Relational Leadership Theory: Exploring the social processes of leadership and organizing

While the concept of relationship-oriented behavior has been around since the earliest formal studies of leadership in organizations (Stogdill and Coons, 1957), the term relational leadership is surprisingly new (Brower et al., 2000; Drath, 2001; Murrell, 1997; Uhl-Bien, 2003, 2005). Because of this, its meaning is still uncertain.
Purification and characterization of chick intestine brush border membrane. Effects of 1alpha(OH) vitamin D3 treatment.

A new technique has been developed for the isolation of membrane vesicles from the vitamin D-deficient and vitamin D-treated chick intestinal brush border membrane. The technique involves removal of nuclei from a low speed pellet by discontinuous sucrose gradient centrifugation. The resulting intact brush borders are then homogenized in 0.5 M Tris and the membrane fragments purified on a glycerol gradient. This preparation represents a 20-fold purification of the brush border marker sucrase. After 1α-hydroxyvitamin D3 treatment there is a significant increase in membrane phospholipid phosphorous, an alteration in the fatty acid composition of the phosphatidylcholine fraction of membrane phospholipid, and a decrease in sucrase specific activity.
Identification of the Epidural Space: Is Loss of Resistance to Air a Safe Technique? A Review of the Complications Related to the Use of Air

Background and Objectives The major determinant of successful epidural anesthesia is the localization of the epidural space. The manual loss of resistance technique is widely used by anesthesiologists in identifying the epidural space. Should air or saline be used in detecting the point of loss of resistance? No consensus exists as to which technique is superior, and individual providers currently use the technique with which they are most comfortable. The incidence of adverse effects associated with the use of epidural air is unknown and may be underreported as the effects may be unrecognized or considered trivial. The authors comprehensively review the complications of epidural air from published reports. Methods Using the appropriate key words, the authors searched the Medline (National Library of Congress) scientific data bank from 1966 to 1995, for case reports of epidural complications. Results There are few prospective, controlled, double-blinded studies comparing the relative merits of using air versus saline for the loss of resistance technique of epidural placement. There are, however, numerous case reports. Complications associated with the use of air for the loss of resistance technique included pneumocephalus, spinal cord and nerve root compression, retroperitoneal air, subcutaneous emphysema, and venous air embolism. Additionally, inadequate analgesia and paresthesia have been associated with the loss of resistance technique using air. Transient and permanent neurologic sequelae have been attributed to some of the complications. The simultaneous administration of nitrous oxide and positive. Pressure ventilation has also been reported to expand localized collections of air, resulting in heightened symptoms. Conclusions The potential complications associated with the use of air for identifying the epidural space with the loss of resistance technique may outweigh the benefits. The use of saline to identify the epidural space may help to reduce the incidence of these complications.
A moving mesh approach for simulation budget allocation on continuous domains

We introduce a moving mesh algorithm for simulation optimization across a continuous domain. During each iteration, the mesh movement is determined by allocating simulation runs to partitions of the domain that are critical in the process of identifying good solutions. The partition boundaries are then adjusted to equally distribute the allocation runs between each partition. To test the moving mesh algorithm, we implemented it using the OCBA method to allocate simulation runs to each partition. But, the simplicity of the procedure should provide flexibility for it to be used with other simulation optimization techniques. Results are presented for several numerical experiments and suggest that the technique has potential given further development.
Evidence for multiple signaling pathways in single squid olfactory receptor neurons

At least two different G-protein-mediated transduction cascades, the adenylate cyclase and phospholipase C (PLC) pathway, process chemosensory stimuli for various species. In squid olfactory receptor neurons (ORNs), physiological studies indicate that both pathways may be present; however, confirmation of the transduction molecules at the protein level is absent. Here we provide evidence that the G-proteins involved in both adenylate cyclase and PLC pathways are present in squid ORNs (Lolliguncula brevis). We used immunoblotting to show that Galpha(olf), Galpha(q), and a downstream effector, enzyme PLC140, are present in the squid olfactory epithelium (OE). To localize these proteins to one or more of the five morphological cell types described for squid OE, paraformaldehyde-fixed olfactory organs were cryosectioned (10 microm), double-labeled for Galpha(olf), Galpha(q), or PLC140, and imaged. Analysis of serial sections from entire olfactory organs for epithelial area and patterns of immunofluorescence revealed a region of highest immunoreactivity at the anterior half of the organ. At the cellular level, type 1 cells could not be distinguished morphologically and were not included in the analysis. The three labeling patterns observed in type 2 cells were Galpha(q) alone, PLC140 alone, and colocalization of Galpha(q) and PLC140. Subsets of cell types 3, 4, and 5 showed colocalization of Galpha(olf) with Galpha(q) but not with PLC140. These data suggest that the PLC pathway predominates in type 2 cells; however, coexpression of Galpha(olf) with Galpha(q) in cell types 3, 4, and 5 suggests that both pathways may participate in olfactory transduction in non-type 2 squid ORNs.
Vasoactive properties of phenylpropanolamine (d, I-norephedrine) and its enantiomers in isolated rat caudal artery

The sympathomimetic properties of PPA and its individual component enantiomers d- and l-norephedrine (NOR) were examined in isolated perfused/superfused caudal arteries from Sprague-Dawley (SD) rats. Segments of caudal artery were cannulated, mounted in a tissue bath, and perfused with a modified Kreb's solution. PPA, d- and I-NOR were alternately injected into the perfusion stream, and vasoconstriction was measured as the rise in perfusion pressure. Various drugs were added to the perfusion buffer to determine the activity of PPA, d-, and I-NOR at specific adrenoceptor subtypes and to determine whether the actions of these vasoconstrictors were influenced by calcium channel antagonists, cocaine, or reserpine. The results demonstrated that the norephedrines acted as partial agonists primarily via direct stimulation of postjunctional alpha1-adrenoceptors with relatively low potency; however, I-NOR did have significant activity at beta-adrenoceptors with relatively low potency; however, I-NOR did have significant activity at beta-adrenoceptors as well. When the enantiomers of PPA were compared, d-NOR had only minor vasoconstrictor activity, relative to I-NOR, which was well over 100 times less potent than the endogenous.
Magic angle lifetime measurements in evanescent wave fluorometry

For fluorescence lifetime measurements in isotropic solutions, it is well known that detection using an emission polarization of 54.7°, the so-called magic angle, eliminates contribution of molecular reorientation to the fluorescence decay function. For macroscopically oriented samples and evanescent wave excitation, the magic angle may not necessarily be the 54.7°. With the use of a typical optical scheme of evanescent wave excitation and detection along the surface normal, a mathematical expression is derived for the magic angle condition. The magic excitation angle is shown to be a function of the angle of incidence of the excitation beam and the refractive indices of the two media involved in total internal reflection. The magic angle relations are valid regardless of the orientational distribution of molecules along the surface normal. The magic angle relations apply to cases where the in-plane orientational distribution is isotropic.
Clinical evaluation of a wireless intra-vaginal pressure transducer

Objective To describe the development, feasibility and validity of a wireless intra-vaginal pressure transducer (IVT) which can be used to measure intra-abdominal pressure in real-world settings.
A STUDY OF SIEVE ELEMENT STARCH USING SEQUENTIAL ENZYMATIC DIGESTION AND ELECTRON MICROSCOPY

The fine structure of plastids and their starch deposits in differentiating sieve elements was studied in bean (Phaseolus vulgaris L.). Ultrastructural cytochemistry employing two carbohydrases specific for different linkages was then used to compare the chemical nature of "sieve tube starch" (the starch deposited in sieve elements) with that of the ordinary starch of other cell types. Hypocotyl tissue from seedlings was fixed in glutaraldehyde, postfixed in osmium tetroxide, and embedded in Epon-Araldite. Treatment of thin sections on uncoated copper grids with α-amylase or diastase at pH 6.8 to cleave α-(1 → 4) bonds resulted in digestion of ordinary starch grains but not sieve element grains, as determined by electron microscopy. Since α-(1 → 6) branch points in amylopectin-type starches make the adjacent α-(1 → 4) linkages somewhat resistant to hydrolysis by α-amylase, other sections mounted on bare copper or gold grids were treated with pullulanase (a bacterial α-[1 → 6] glucosidase) prior to digestion with diastase. Pullulanase did not digest sieve element starch, but rendered the starch digestible subsequently by α-amylase. Diastase followed by pullulanase did not result in digestion. The results provide evidence that sieve element starch is composed of highly branched molecules with numerous α-(1 → 6) linkages.
The unity of law and morality: A refutation of legal positivism

(1987). The Unity of Law and Morality: A Refutation of Legal Positivism. The Journal of Higher Education: Vol. 58, No. 2, pp. 235-237.
Dielectric relaxation in ceramics with an intragrain concentration gradient

We created a material with a composition gradient within each grain. Due to the graded composition the ceramic does not show a sharp change in dielectric constant near the relaxation frequency. Instead, we observe gradual decrease in dielectric constant with frequency, with the loss tangent remaining practically unchanged (below 0.02 everywhere within the frequency range 0.0003–3 GHz). The tunability of the ceramic decreases with increasing frequency but remains in the order of 10% at 3 GHz. Thus we conclude that the dielectric relaxation in high purity (Ba,Sr)TiO3 occurs predominantly by Ti 4+ ion hopping relaxation. We also expect that the concept of intragrain concentration gradient ceramics may become a useful material for a wide range of electronic devices. PACS: 77.22.Gm, 77.22.Ch, 77.84.Dy # 2002 Elsevier Science Ltd. All rights reserved.
Consumer Perceptions and Willingness to Pay for Intrinsically Motivated Online Content

Providing profitable online content has been an elusive goal, challenging many companies such as the New York Times, Disney/ABC/ESPN, and Microsoft/Slate. Charging for content has been hit-or-miss, attributable to a lack of generally applicable models of information value. Previous studies in the management information systems literature emphasized extrinsically motivated content (addressing tangible gains), while many sites target intrinsic goals such as entertainment or education. This study examines potential factors influencing willingness to pay for intrinsically motivated online content. Data from 392 college students indicate that even when analyzing content whose potential rewards are intangible and nonquantifiable, potential consumers focus on "expected benefits" as the main antecedent for willingness to pay. Other antecedents, such as perceived quality and provider reputation, only affected willingness to pay indirectly through expected benefits. Researchers are offered a baseline model for future study, and practitioners are advised to provide initial visitors a clear message about benefits of use to entice them to pay for content.
DB2 security features: audit facility and SSL

To manage access to sensitive data, a variety of authentication and access control mechanisms can be used to establish rules and controls for known and acceptable data access behaviors. But, to protect against and discover unknown or unacceptable behaviors, you also need to monitor data access. To assist you in this task, the DB2® database system provides an audit facility.
The effect of hypothalamic lesions and hypophysectomy on adrenal weight in Sceloporus cyanogenys.

Abstract Adrenal hypertrophy was induced in male Sceloporus cyanogenys with Metyrapone. Radiofrequency lesions of the anteromedial hypothalamus and of the median eminence were followed by a decrease in the weights of the adrenal glands compared to those of the control animals, and hypertrophy of the glands did not occur following metyrapone. Both sham-operation and lesions of other areas of the brain (cerebral hemisphere, posterior and lateral hypothalamus) increased adrenal weight; however, the weight increase induced by sham-operation was less than that induced by lesions of these areas of the brain. While Metyrapone increased adrenal weight in all groups other than those with lesions of the anteromedial hypothalamus and median eminence, the increase over and above that caused by the lesions of other areas of the brain was not statistically significant. Lesions of the hypothalamus, wherever placed, increased thyroid weight whereas lesions of the cerebral hemispheres did not. Hypophysectomy prevented the adrenal weight response to Metyrapone, and the injection of ACTH increased adrenal weight in both intact and hypophysectomized animals.
Parse scoring with prosodic information: an analysis/synthesis approach

Abstract Prosody is used by human listeners to disambiguate spoken language and, in particular, the relative size and location of prosodic phrase boundaries provides an important cue for resolving syntactic ambiguity. Therefore, automatically detected prosodic phrase boundaries should provide information useful in speech understanding for choosing among several candidate parses. Here, we propose two scoring algorithms to rank candidate parses, both based on an analysis/synthesis approach that compares the recognized prosodic phrase structure (analysis) with the predicted structure (synthesis) for each candidate parse. The two scoring algorithms, one rule-based and one using a probabilistic model, yield similar overall results when evaluated in experiments with a corpus of ambiguous sentences read by FM radio announcers. To decouple the performance of the analysis and synthesis components, we have used the scoring algorithms with hand-labeled breaks, which results in disambiguation performance comparable to the performance of human subjects in perceptual experiments. Performance degrades somewhat using automatically recognized breaks.
Determination of the Orientation of NO2− in KI by Persistent IR Spectral Hole Burning

Interpretation des proprietes dynamiques de molecules isolees dans des solides, par identification de l'orientation de la molecule dans son etat fondamental. On demontre comment identifier correctement la configuration de l'etat fondamental de telles molecules
The Rhetoric of Public Administration

The short essay that follows is the result of an invitation from the editor to comment on public administration or service in light of the events of September 11,2001 and those subsequent thereto. More responses will follow in future issues. If others are moved to write such an essay, please contact the editor.
Cost‐effectiveness of chemotherapy for sputum smear‐positive pulmonary tuberculosis in Malawi, Mozambique and Tanzania

The cost-effectiveness of chemotherapy for pulmonary sputum smear-positive tuberculosis was examined in the national tuberculosis control programmes of Malawi, Mozambique and Tanzania. In these three programmes, routine cure rates have exceeded 80 per cent. Average, average incremental and marginal unit costs for standard, short-course and retreatment regimens with and without hospitalization have been measured. The average incremental cost per year of life saved through chemotherapy ranged from US $0.90-3.10. In all conditions, short-course chemotherapy is preferable to standard 12-month chemotherapy. When hospitalization during the intensive phase of chemotherapy increases the cure rate by 10-15 percentage points, it can be relatively cost-effective. Analysing the cost-effectiveness of short-course and standard chemotherapy, where the depth of the margin of benefit is different, illustrates some of the dangers of simplistic use of cost-effectiveness ratios.
Representation of harmonic complex stimuli in the ventral cochlear nucleus of the chinchilla.

The representation of Schroeder-phase harmonic complex sounds in the ventral cochlear nucleus (VCN) of the anesthetized chinchilla was studied. Stimuli consisted of a series of harmonically related sinusoids, multiples of a fundamental frequency (f0), summed in either negative (−SCHR) or positive (+SCHR) Schroeder phase. Psychoacoustic experiments performed in humans by other investigators have revealed that masking effects of −SCHR stimuli are larger than those found using +SCHR stimuli as maskers. In our laboratory, basilar membrane measurements at the base of the chinchilla cochlea show that responses to −SCHR stimuli are less “peaked,” or modulated, than responses to +SCHR stimuli. We also found that suppression of a characteristic-frequency (CF) tone by −SCHR stimuli is larger than that evoked by +SCHR stimuli. Rate-intensity functions display higher firing rates in responses to −SCHR stimuli than in those produced by +SCHR stimuli. Firing rates evoked by either −SCHR or +SCHR stimuli saturate at low...
Top Down proteomics: Facts and perspectives

The rise of the "Top Down" method in the field of mass spectrometry-based proteomics has ushered in a new age of promise and challenge for the characterization and identification of proteins. Injecting intact proteins into the mass spectrometer allows for better characterization of post-translational modifications and avoids several of the serious "inference" problems associated with peptide-based proteomics. However, successful implementation of a Top Down approach to endogenous or other biologically relevant samples often requires the use of one or more forms of separation prior to mass spectrometric analysis, which have only begun to mature for whole protein MS. Recent advances in instrumentation have been used in conjunction with new ion fragmentation using photons and electrons that allow for better (and often complete) protein characterization on cases simply not tractable even just a few years ago. Finally, the use of native electrospray mass spectrometry has shown great promise for the identification and characterization of whole protein complexes in the 100 kDa to 1 MDa regime, with prospects for complete compositional analysis for endogenous protein assemblies a viable goal over the coming few years.
Patterns of dye coupling in the imaginal wing disk of Drosophila melanogaster

Responses of developing tissues to experimental disruption demonstrate that cell interaction is important both in generating positional information and in controlling growth. However, the mechanism by which cells interact and the range over which the interactions are effective are not known. In the imaginai disks of Drosophila melanogaster, experiments on pattern regulation following surgical ablation suggest that the cell interactions are very local in nature; in fact, most of the data can be explained by assuming that cells interact only with their immediate neighbours. In contrast, studies of cell division patterns in the same tissue indicate that the ‘local’ proliferative response to an ablation extends over a distance of up to about eight cell diameters. Still longer-range interactions have been proposed on the basis of theoretical considerations. It is possible that the interactions are mediated by the transfer of small molecules through gap junctions, as gap junctions are abundant in imaginai disks at the appropriate developmental stages. We have explored the range, timing and directionality of dye coupling between the cells of the wing disk as a test of the possible role of gap junctions in imaginai disk patterning. Our results indicate that interactions over different ranges are possible depending on the nature of the molecule being transferred.
Giving expert advice

Many of you have expertise but get ignored by those in charge. I offer a little unsolicited advice to expert advisors. The archetypal expert is the wise confidante, the advisor who has the ear of an executive decision maker. This expert serves the decision maker and measures much of his or her personal success in terms of access to and influence over that executive.
Supported liquid-phase catalysis: II. Experimental evaluation of the flux model for liquid-loaded porous media

Abstract An experimental investigation was undertaken to test the model for transport of gases in liquid-impregnated porous media proposed in Part I (R. Datta and R. G. Rinker, J. Catal. 95, 181, 1985) of this series. It was found that the original dusty-gas model needs to be modified by incorporating an additional slip-flow correction factor, σ, in order to reconcile differences in the values of the Knudsen diffusion constant, C1O, obtained separately from isobaric diffusion and flow experiments. Based on the results of the permeability experiments with pure gases and binary mixtures and earlier isobaric diffusion experiments, it is concluded that the correlations proposed to account for the variation of the dusty-gas parameters C0G, C1G, and C2G with degree of liquid loading are entirely adequate. It is also indicated that the dispersion pattern of liquids with a contact angle less than 90 ° is substantially the same in a given porous medium.
On the Extent of Dominance of Asymptotic Elastodynamic Crack-Tip Fields: Part I—An Experimental Study Using Bifocal Caustics

The question of the domain of dominance of mode I asymptotic elastodynamic crack-tip fields is investigated experimentally for the cases of dynamically loaded stationary cracks as well as dynamically propagating cracks. The experiments reported are on three-point bend specimens loaded dynamically using a drop-weight tower. An optical configuration leading to a bifocal high-speed camera is proposed. This is used in conjunction with the method of caustics to obtain apparent dynamic stress intensity factor measurements simultaneously from two different regions around the crack tip. The results of this study indicate that three-dimensional and transient effects necessarily have to be taken into account in the interpretation of dynamic fracture experiments.
Systemic perfusion: a method of enhancing relative tumor uptake of radiolabeled monoclonal antibodies

We evaluated the feasibility of systemic vascular perfusion with saline (mimicking plasmapheresis) as a method to enhance tumor-specific monoclonal antibody (MoAb) tumor/background ratios. Initially, groups of rats were injected intravenously (i.v.) with i3’I-5G6.4 MoAb (mutine IgGZaK reactive with ovarian carcinoma). These animal’s radioactivity levels were determined by dose calibrator and they were imaged before and after perfusion which was conducted at 4 or 24 h post-antibody injection. Animals were sacrificed after perfusion, as were controls, and normal organ radioactivity levels determined. In addition, nude mice bearing HTB77 ovarian cancers subcutaneously were injected i.v. with 13’1-5G6.4 MoAb and were imaged before and after systemic perfusion with saline 24 h post-5G6.4 injection. Perfusion in rats dropped whole-body 566.4 levels significantly at both perfusion times (P < 0.0005). The drop in whole-body radioactivity with perfusion was significantly greater for the animals perfused at 4 h post i.v. 566.4 antibody injection (48.3 + 5.1%) than for those perfused at 24 h post i.v. antibody injection (32.9 f. 2.9%) (P < 0.025). In the nude mice with ovarian cancer xenografts, y camera images of tumors were visually and quantitatively (by computer image analysis) enhanced by perfusion, with a 2.33-fold greater decline in whole body uptake than in the tumor (P < 0.05). These studies show that (1) much background antibody radioactivity can be removed using whole-body perfusion with saline, (2) that the decline in whole body activity is larger with 4 than 24 h perfusion and (3) tumor imaging can be enhanced by this approach. This and similar approaches that increase relative tumor antibody uptake such as plasmapheresis may be useful in imaging and therapy with radiolabeled antibodies.
Lipoprotein of Gram-negative bacteria is essential for growth and division

THE lipoprotein of Gram-negative bacteria has become a cell surface component of central interest following its characterisation by Braun and coworkers1. This small protein (molecular weight 7,500) is unique in containing as its N-terminal amino acid a glycerylcysteine to which three fatty acids are covalently bound2. It is also unusual in its subcellular distribution: one-third of the total lipoprotein is covalently linked to the cell wall peptidoglycan while the remaining two-thirds exists in an unlinked or “free” form in the outer membrane4. Free and murein-linked lipoprotein seem to be identical in structure5,6, and pulse–chase experiments indicate that free lipoprotein is the precursor to murein-linked lipoprotein4. Braun's lipoprotein or an immunologically related protein has been found in a wide variety of Gram-negative organisms7,8, and in Escherichia coli is present in about 3 × 105 copies per cell1. These observations suggest that lipoprotein performs some essential function(s); however, the nature of that function is unknown. It has been suggested that lipoprotein may have a role in anchoring the outer membrane to the cell wall3, or function in transporting small molecules through the outer membrane9 or be involved in cell division10,11. To clarify the role of Braun's lipoprotein, we have isolated a mutant deficient in its synthesis.
Phospholipid Biosynthesis : The Activity of Phosphatidic Acid Phosphohydrolase in the Developing Lung and Amnionic Fluid

The presented data suggest that PAPase may, indeed, be important in the biosynthesis of lung phospholipids. The observed increase in the specific activity of rabbit lung precedes the "surge" of phosphatidylcholine concentration and surfactant biosynthesis by at least 24 hours. In human amnionic fluid, PAPase specific activity was markedly increased in pregnancies of 35 weeks of gestation or more. The increase in the specific activity of PAPase preceded the "surge" of acetone precipitated phosphatidylcholine. The reported studies may provide an additional procedure to examine the problems associated with surfactant biosynthesis.
Relationships between subcellular distributions of cadmium and perturbations in reproduction in the polychaete Neanthes arenaceodentata

Abstract The accumulation and subcellular distribution of Cd in the polychaete worm, Neanthes arenaceodentata , were examined following an eleven-week period of exposure to a range of free cadmium ion activities, [Cd 2+ ]. The accumulation of Cd in N. arenaceodentata was directly proportional to [Cd 2+ ] in seawater at lower concentrations (10 −12 M to 10 −10 M) but deviated from proportionality at higher concentrations (10 −9 M and 10 −8 M). This deviation in proportionality at higher [Cd 2+ ] was attributable to a relative increase in the concentration of metal associated with the metallothionein and the very low molecular weight metal-ligand pools of the cytosol. Reproductive potential was also monitored in these organisms to examine the ecological significance of Cd accumulation and shifts in its subcellular distribution. Perturbations in reproduction were observed at 10 −8 M [Cd 2+ ] which coincided with the deviation in proportionality of Cd accumulation and increased accumulation of Cd in the cytosol.