cssi/SciSciGPT-SciSciNet huggingface dataset:
Production and performance of multilayer coated conic sections

Previously we have reported on our work on coating a truncated-cone-shaped engineering (not high quality in terms of smoothness) mandrel and have removed the layers, intact, on the inside of an electroform with a cylindrical, truncated-cone geometry. We have advanced to using a high quality (about 0.5 nm) smooth truncated cone. We report our latest advances in refining our fabrication techniques and the results of X-ray measurements. The X-ray measurements made at the Argonne APS SRI-CAT 2-BM-B beam-line were at 10 and 30 keV. The results showed that we had produced excellent Si/W multilayers on the inside of a 10 cm long by about 10 cm diameter truncated cone shaped mirror. We estimate the reflectivity of the layers at the primary Bragg peak to be well above 10%. We also show that the multilayers were uniform around the mirror.
Comparative ultrastructure of selected oral streptococci: thin-sectioning and freeze-etching studies.

The ultrastructure of Streptococcus mutans, serotypes a–e, S. sanguis, S. mitis, and S. salivarius HHT, were examined by the techniques of thin-sectioning and freeze-etching. The cell walls varied in width between 15 and 46 nm and were covered with an electron-dense fibrillar or fuzz layer. The cytoplasmic membrane was in close association with numerous mesosomes which were, in turn, either closely associated or in contact with the bacterial chromosome. In freeze-etch replicas, the outermost layer of the cell wall was fibrous, and the cytoplasmic membrane was covered with particles composed of several subunits. Both particle-clusters and particle-free areas occurred on the surfaces of the cytoplasmic membrane, as well as a crystalline array in the ground plasm of the cell.
Hormones and Factors That Stimulate Growth of a Rat Islet Tumor Cell Line in Serum-Free Medium

A number of hormones and factors were found to stimulate growth of cultured rat islet tumor cells, the RIN-r cell line. A serum-free supplemented medium from RIN-r cells was formulated. It consisted of a 1:1 mixture of Ham's F12 and DME media with the addition of insulin, transferrin, triiodothyronine, prolactin, growth hormone, and an extract of proteose peptone (medium IM). The growth rate of RIN-r cells in this medium is as great as it is in 10% serum-supplemented medium. Up to 10 populations doublings occurred over a period of 20 days. Insulin is a very effective mitogen for RIN-r cells and has an effect on concentrations as low as 30 ng/ml. In addition, the insulin-like somatomedin, multiplication stimulating activity (MSA), is a growth factor at 50 ng/ml. It was found that RIN-r cells proliferate and continue to produce immunoreactive insulin in a hormonally and nutritionally defined medium. This medium is derived from medium IM, in which insulin is replaced with MSA and proteose peptone is omitted. Variations of this medium may prove useful in studies on the growth and function of the normal islets in long-term primary culture.
Chemical environment and Ce valence: Global trends in transition-metal compounds.

Results of ${L}_{\mathrm{III}}$ absorption spectroscopy measurements on a wide range of Ce--transition-metal (T) compounds are presented and Ce valence-state estimates are made. We are able to identify extremely regular trends in the response of the Ce valence and Ce-T hybridization strength to systematic variations in the solid-state chemical environment. Our work facilitates identification of the specific elements in the T-metal electronic structure which drive the Ce valence-state change.
Reducing the Berreman 4 × 4 propagation matrix method for layered inhomogeneous anisotropic media to the Abelés 2 × 2 matrix method for isotropic media

With the use of the exact expression for the local propagation matrix that was obtained by Wohler et al. [ J. Opt. Soc. Am. A5, 1554 ( 1988)], we show explicitly that the Berreman 4 × 4 propagation matrix method for layered inhomogeneous anisotropic media reduces to the Abeles 2 × 2 propagation matrix method for layered inhomogeneous isotropic media when the anisotropic medium becomes isotropic. The optical properties of isotropic and anisotropic media have been extensively studied, and a number of schemes for the computation of the optical effects of layered inhomogeneous media have been proposed. Propagation matrix methods have been shown to be particularly useful for studying the reflection and the transmission of electromagnetic waves by layered inhomogeneous isotropic and anisotropic media.1–5 Generally, the Abeles 2 × 2 matrix method is used for layered inhomogeneous isotropic media,1,2,4,5 and the Berreman 4 × 4 matrix method is used for layered inhomogeneous anisotropic media.3 The 4 × 4 matrix method is more general than the 2 × 2 matrix method and is applicable to problems involving media of low optical symmetry.
Use of zerotree coding in a high-speed pyramid image multiresolution decomposition

A Zerotree (ZT) coding scheme is applied as a post-processing stage to avoid transmitting zero data in the High-Speed Pyramid (HSP) image compression algorithm. This algorithm has features that increase the capability of the ZT coding to give very high compression rates. In this paper the impact of the ZT coding scheme is analyzed and quantified. The HSP algorithm creates a discrete-time multiresolution analysis based on a hierarchical decomposition technique that is a subsampling pyramid. The filters used to create the image residues and expansions can be related to wavelet representations. According to the pixel coordinates and the level in the pyramid, N2 different wavelet basis functions of various sizes and rotations are linearly combined. The HSP algorithm is computationally efficient because of the simplicity of the required operations, and as a consequence, it can be very easily implemented with VLSI hardware. This is the HSP's principal advantage over other compression schemes. The ZT coding technique transforms the different quantized image residual levels created by the HSP algorithm into a bit stream. The use of ZT's compresses even further the already compressed image taking advantage of parent-child relationships (trees) between the pixels of the residue images at different levels of the pyramid. Zerotree coding uses the links between zeros along the hierarchical structure of the pyramid, to avoid transmission of those that form branches of all zeros. Compression performance and algorithm complexity of the combined HSP-ZT method are compared with those of the JPEG standard technique.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Évolutions technologiques récentes dans le domaine des réacteurs à eau pressurisée (PWR)

Depuis la commande de la chaudiere de Fessenheim 1, intervenue en 1970, certaines adaptations ou modifications technologiques ont marque l'evolution des reacteurs a eau pressurisee en France. L'auteur decrit les principales modifications apportees aux differents composants des reacteurs en analysant les raisons qui sont a leur origine.
Well-ordered mesoporous silica prepared by cationic fluorinated surfactant templating

Abstract We describe the synthesis and characterization of ordered mesoporous silica using the template 1H,1H,2H,2H-perfluorooctylpyridinium chloride. This surfactant forms several lyotropic mesophases at room temperature, including hexagonal close packed cylinders, an isotropic liquid crystal, and a lamellar phase. Using this surfactant, mesoporous silica is synthesized by room temperature precipitation and surfactant extraction. Both the surfactant and product material are thoroughly characterized. From nitrogen adsorption, the product has a specific surface area of 982 m2/g and a pore diameter of 2.6 nm. X-ray diffraction and transmission electron microscopy confirm two-dimensional close-packed hexagonal long-range ordering. This is the first example of cationic fluorinated surfactant templating of an ordered porous ceramic material.
Cutaneous features of Crouzon syndrome with acanthosis nigricans.

Importance Crouzon syndrome with acanthosis nigricans is a distinct disorder caused by a mutation in the FGFR3 gene, featuring craniosynostosis, characteristic facial features, and atypical and extensive acanthosis nigricans. Other cutaneous findings have not been thoroughly described. Observations We report 6 cases and summarize the existing literature with regard to the cutaneous manifestations of this disorder. All patients have widespread, early-onset acanthosis nigricans. Patients often have prominent hypopigmented scars at surgical sites and nevi arising early in childhood. Conclusions and Relevance In addition to craniofacial malformations, Crouzon syndrome with acanthosis nigricans results in characteristic cutaneous findings.
Inverse scattering for discrete transmission—line models

This paper presents several methods for the identification of the impedance and reflection coefficient profile of a nonuniform, discrete transmission-line from its response to a given forcing function. This problem is the prototype for a wealth of one-dimensional inverse scattering problems arising in various fields. A unified, straightforward approach is presented, providing all known inversion procedures and some novel ones. The derivations readily follow from causality of signal propagation on the transmission-line. It is shown that a direct exploitation of the signal propagation model leads to recursive, computationally efficient and reliable inversion algorithms. In particular, the relationships between layer peeling (Schur type, difference equation) and layer-adjoining (Levinson type, integral equation) algorithms are clearly displayed.
The past, present, and future of reading diagnosis and remediation

Reading remediation has dramatically changed since its beginnings approximately 100 years ago. Research into causation of reading difficulties has progressed from cognitive deficit models to learning styles and back to brain functionality. Classroom teachers and teacher educators alike must refine their practices to meet the ever-changing needs of their students. The instructional delivery methods and strategies used today must match the 21st century needs of students in the age of digital literacy. A brief history of the past, present, and future trends of reading diagnosis and remediation is explained.
High F0 and musicianship make a difference: Pitch-shift responses across the vocal range

Abstract The control of vocal pitch plays a central role in speech and singing, where accurate tonal production relies on modulating F 0 production. Previous research has shown that vocal pitch is modulated in response to artificial pitch perturbations during ongoing vocalization (i.e., the pitch-shift response) with response characteristics differing between musicians and non-musicians. However, little is known about the behavior of these responses in the higher portion of a speaker's vocal range for amateur musicians or non-musicians. The present study addresses whether pitch control changes as target pitch is systematically increased and whether this variation is affected by musicianship. We predicted that as F 0 moves away from comfortable speaking level, pitch-shift response peak amplitude would increase and peak latency would decrease, while participants with musical experience would have lower amplitude responses than those without experience. Results showed that peak amplitude linearly increased as F 0 was raised, and that peak latency similarly decreased but with more variability. However, musical participants had larger pitch-shift response amplitudes and longer peak latency times than non-musical participants, which is an unanticipated finding for persons with musical training. These patterns suggest that pitch control can be manipulated by vocal tasks that vary F 0 while still being subject to strong modulation by musical background.
A New Framework for Electron-Transfer CalculationsBeyond the Pathways-like Models

We present a framework for analyzing and understanding the underlying mechanisms for the electron-transfer (ET) tunneling matrix element. Four principal issues that could not be addressed by the Pathways-like models are investigated: sensitivity to the choice of the Hamiltonian, effects of the interference among pathways, sensitivity to the bridge coordinates, and effects of the bridge motion. Our framework classifies the orbital interactions by using the overlapcoupling (S−H) maps and identifies the dominant pathways, as well as interference among them, mediated by these different classes of interactions. This strategy provides a clear view of how structural motifs of the bridge control TDA and identifies, even without performing the dynamical calculations, the situations where TDA is highly sensitive to the structural details and thermal motion. Even though the details of the interference mechanism depend on the choice of the Hamiltonian, the qualitative features obtained by this framework should not b...
Implementation of a vehicular networking architecture supporting dynamic spectrum access

In this paper, we present a prototype of a decentralized vehicular communications networking architecture that is capable of performing dynamic spectrum access (DSA) while operating under mobile conditions. Referred to as vehicular dynamic spectrum access (VDSA) networking, our prototype implementation employs software-defined radio (SDR) technology at each of the vehicular wireless nodes that have been programmed to simultaneously perform multi-hop routing and DSA. To evaluate the proposed VDSA implementation, a prototype network consisting of four mobile nodes was deployed in an actual highway operating environment, where the wireless transmission links between any two vehicular nodes were established using unoccupied portions of the ISM band between 2.4 GHz and 2.5 GHz. The performance of the proposed VDSA networking architecture was assessed experimentally in terms of the completion of end-to-end multi-hop relaying across the four vehicular nodes, the overall data throughput, and the network latency. The experimental results show that the proposed network architecture performed a combination of DSA and multi-hop routing with the efficiency of up to 72.5% per hop
Computer use in geography.

Computer manipulation of geographical data involves record matching, testing of theories, production of maps, and spatial pattern analysis. A brief review is presented of the operational status of computer programs in these areas.
The past, present, and future of clinical specular microscopy.

Since the introduction of specular microscopy into the field of clinical ophthalmology in 7975,1 many technological and methodological advances have been made. These have for the most part eliminated the previously discussed objections to the use of specular microscopy as a clinical tool. 2 With the advent of new instrumentation, a number ol specular microscopes are now available. The advantages and disadvantages of these clinical specular microscopes, current clinical practice with small-field and wide-field specular microscopy, and description of problems and possible future developments of specular microscopy are discussed.
Neuroendocrine dysfunction in polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a common disorder characterized by ovulatory dysfunction and hyperandrogenemia (HA). Neuroendocrine abnormalities including increased gonadotropin-releasing hormone (GnRH) pulse frequency, increased luteinizing hormone (LH) pulsatility, and relatively decreased follicle stimulating hormone contribute to its pathogenesis. HA reduces inhibition of GnRH pulse frequency by progesterone, causing rapid LH pulse secretion and increasing ovarian androgen production. The origins of persistently rapid GnRH secretion are unknown but appear to evolve during puberty. Obese girls are at risk for HA and develop increased LH pulse frequency with elevated mean LH by late puberty. However, even early pubertal girls with HA have increased LH pulsatility and enhanced daytime LH pulse secretion, indicating the abnormalities may begin early in puberty. Decreasing sensitivity to progesterone may regulate normal maturation of LH secretion, potentially related to normally increasing levels of testosterone during puberty. This change in sensitivity may become exaggerated in girls with HA. Many girls with HA—especially those with hyperinsulinemia—do not exhibit normal LH pulse sensitivity to progesterone inhibition. Thus, HA may adversely affect LH pulse regulation during pubertal maturation leading to persistent HA and the development of PCOS.
Inhibitory effects of probenecid on the individual transport routes which mediate the influx and efflux of methotrexate in L1210 cells

L1210 cells contain a single transport system which mediates the influx of methotrexate and at least three routes for drug efflux [G. B. Henderson and E. M. Zevely, J. biol. Chem. 259, 1526 (1984)]; each of these processes is sensitive to probenecid. The influx carrier was inhibited reversibly and completely by probenecid with a Ki of 0.25 mM, while efflux via the same system was relatively unaffected by this compound (50% inhibition above 2.0 mM). The two remaining efflux routes (which do not contribute to methotrexate influx) showed a much higher sensitivity to probenecid. Efflux via these components was reduced half-maximally at probenecid concentrations of 0.08 and 0.22 mM, respectively, and a complete block was achieved with excess amounts (2.0 mM) of the inhibitor. Intracellular levels of ATP, glucose metabolism, and the membrane potential were also reduced by probenecid, indicating that the mechanism for inhibiting methotrexate efflux may involve the ability of probenecid to act as a metabolic inhibitor. Probenecid may have a broad capacity for inhibiting anion transport processes since it also reduced sulfate influx and efflux via the general anion carrier system.
Using MALDI-TOF Mass Spectrometry to Characterize Interfacial Reactions on Self-Assembled Monolayers

This paper demonstrates that matrix-assisted laser desorption/ionization and time-of-flight mass spectrometry (MALDI-TOF MS) is very well suited for characterizing self-assembled monolayers (SAMs) of alkanethiolates on gold and, in particular, for analyzing chemical reactions on monolayers. Three examples establish the generality of MALDI-TOF for this purpose. The first example characterizes the Diels−Alder reaction of a cyclopentadiene to maleimide groups of a monolayer. The second example characterizes the immobilization of glutamine tert-butyl ester to a carboxylic acid terminated monolayer and subsequent removal of the tert-butyl group. The third example characterizes the exchange of alkanethiolates in a monolayer with alkanethiols in a contacting solution. The availability of commercial instruments for MALDI-TOF MS and the straightforward use of this technique for characterizing SAMs will make this an important analytical technique for programs that prepare and apply model substrates in chemistry and...
Interactions of ribonucleotide polymers with tobacco mosaic virus protein to form virus-like particles.

THE purified protein and ribonucleic acid constituents of tobacco mosaic virus can be combined in vitro to form infectious nucleoprotein rods which resemble the original virus in size and shape and which have their nucleic acid surrounded by protein as in the virus1. Although the viral nucleic acid is necessary for infectivity, the formation of rods seems to depend on an inherent property of the viral protein; the latter can be aggregated in the absence of nucleic acid to form cylindrical tubes which superficially resemble the virus2 but possess no infectivity. When the viral nucleic acid is present, it occupies a region within the tube and apparently serves to ‘cement’ the protein sub-units together, since the nucleoprotein particles are stable at pH values higher than those at which the protein tubes disintegrate2. This cementing function might be thought to depend on some property specific to the nucleic acid of tobacco mosaic virus. In order to investigate such a possibility, we have studied the interactions of the viral protein with several widely differing artificial and natural ribonucleotide polymers.
Visceral pain—peripheral sensitisation

The viscera receive dual sensory innervation. The majority of visceral sensory fibres terminate in the spinal cord but sensory fibres contained in the vagus and pelvic nerves, which terminate in the brain stem and lumbosacral spinal cord, respectively, also innervate the same visceral organs. Figure 1 illustrates this unique pattern of innervation for the gastrointestinal tract, classically referred to as sympathetic and parasympathetic, but more appropriately designated by nerve name (for example, hypogastric nerve, pelvic nerve). Figure 1 Representation of visceral sensory innervation of the gastrointestinal tract. The sensory innervation that anatomically exists in association with the sympathetic nervous system is shown on the left. These spinal visceral sensory fibres traverse both prevertebral (CG, coeliac ganglion, IMG, inferior mesenteric ganglion, SMG, superior mesenteric ganglion) and paravertebral ganglia en route to the spinal cord. Pelvic and vagus nerve innervation to the sacral spinal cord and brain stem, respectively, is shown on the right. (Modified from Sengupta and Gebhart.1) Visceral sensory axons are almost exclusively thinly myelinated Aδ fibres and unmyelinated C fibres. Activity in most visceral sensory neurones, whether in vagal afferent fibres or spinal afferent fibres, does not reach consciousness. For example, there is regular input into the central nervous system from gastric and hepatic chemoreceptors, aortic baroreceptors, etc., that is not perceived. Sensory innervation of the gastrointestinal tract involves all layers of a viscus (mucosa, muscle, and serosa) and visceral receptors exhibit chemosensitivity, thermosensitivity, and mechanosensitivity. Visceral receptors, in fact, are generally polymodal in character (that is, respond …
Effects of the partial glycine agonist D-cycloserine on cognitive functioning in chronic low dose MPTP-treated monkeys.

Abstract d -Cycloserine, a partial agonist at the glycine recognition site of the N-methyl- d -aspartate (NMDA) receptor complex, has been shown to facilitate certain forms of memory formation and to improve visual recognition memory in normal monkeys. In the present study, the effects of d -cycloserine on spatial short-term memory deficits in monkeys induced by chronic low-dose 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration were examined. Chronic low-dose MPTP administration resulted in deficits in the performance of a variable delayed-response task (VDR). Single administration of d -cycloserine (320 or 1000 μg/kg) significantly improved the performance on this task. High-dose d -cycloserine (8000 μg/kg) or MK-801 (10-32 μg/kg) administration had no effects on delayed-response performance but impaired performance on a visual discrimination (VD) task that was not adversely affected by MPTP administration. These results show that at low doses, d -cycloserine has cognition-enhancing properties in this model of early Parkinsonism.
Analysis and design of a wideband lumped-element quadrature directional coupler for complementary metal-oxide semiconductor implementation

This study proposes a new wide band quadrature coupler structure using a lumped-element technique. The theoretical operating conditions of the proposed structure are also analysed. The operating bandwidth is extended and the phase shift difference error is reduced by introducing two matching frequency points. When the designed centre frequency is 6 GHz, a theoretical calculation shows that the operating bandwidth is 2 GHz and the phase shift error ranges from −5.9 to 1.76°. A coupler with 6 GHz centre frequency is also designed in a 0.13 µm CMOS process and simulated using Cadence Spectre. The active area of the coupler is 560 µm×640 µm. The post-layout simulation shows that the operating bandwidth has strong tolerance to the process variations.
Electrostatic Potential as a Harbinger of Cation Coordination: CF3SO3- Ion as a Model Example

The topography of molecular electrostatic potential (MESP) has been proposed as a predictive tool for studying ion-pair formation, using the trifluromethanesulfonate (triflate) ion, CF3SO3- (Tf-), as a test example. A model based on electrostatic docking of the cation (Li+, Na+, NH4+) has been developed for studying the different possible coordinating geometries for these ion pairs. The interaction energies of different ion-pair structures estimated by the electrostatic docking model have been found to reproduce about 85% of the corresponding ab initio interaction energies. Furthermore, the geometries predicted by the present model indeed provide a good initial guess for a subsequent ab initio Hartree−Fock calculation. Ab initio local minima are usually found close to the respective geometries derived from the electrostatic docking, the bidentate structure being the most favored one. The topography-based approach thus seems to offer insights into primitive patterns of ion-pair formation. Electron correlat...
Effects of Radial Location on the Migration of Hot Streaks in a Turbine

Experimental data haveshown that combustortemperature nonuniformities can lead to the excessive heating of e rst-stagerotorbladesin turbines. This heating oftherotorblades can lead to thermal fatigueand degradeturbine performance. The results of recent studies have shown that variations in the circumferential location, or clocking, ofthee rst-stagestatorairfoilscanbeused tocontroltheadverseeffectsofthehotstreaksby mixing hot streak e uid with the cooler e uid contained in the e rst-stage stator wake. Less emphasis has been placed on determining the optimal radial location of the hot streaks at the inlet to thee rst-stage stator blade row. In thepresent investigation, three-dimensional unsteady Navier ‐Stokes simulations have been performed for a 1 1 -stage high-pressure turbine geometry operating in subsonic e ow. Combustor hot streaks were included in the simulations. The radial location and the clocking position of the hot streak were varied across the inlet relative to the e rst-stage stator.
First excited state of 121Sb

Abstract The low-energy photon spectra from sources of 121Tem and 121Snm have been investigated. No evidence for a previously reported 9 keV γ ray was obtained and it is concluded that the 37 keV level is the first excited state of 121Sb.
Kinetic analysis of California petroleum source rocks by programmed temperature micropyrolysis

Three California shales were examined by micropyrolysis to determine laboratory pyrolysis kinetics. Samples from the Modelo Formation with 6.16 wt % S in kerogen, Monterey Formation with 13.58 wt % S in kerogen, and with 8.88 wt % S and 13.16 wt % O in kerogen, exhibited shift-in-Tmax and principal discrete distribution energies of 54 and 57, 51 and 52, and 65 and 59 kcal/mol, respectively. These results are evidence that laboratory decomposition kinetics of high sulfur kerogens and, in particular, Monterey kerogens appear not to be governed by organic sulfur content alone, particularly because the kinetic parameters for the 13.16 wt % O Monterey sample were well outside the range generally seen for type I, II, and II-S kerogens, and closer to Type III kerogens.
The Changing Image of Blacks in American Government Textbooks.

The American government textbook is an important tool for the education of students. This article studies the changing images of blacks in American government textbooks. The article reports on the images suggested by twenty-five representative textbooks. Further, the article highlights several areas of concern for the analysis and description of black Americans in the political system.
Dynamics in Insulin Resistance and Plasma Levels of Adipokines in Patients With Acute Decompensated and Chronic Stable Heart Failure

Background Patients with heart failure (HF) develop metabolic derangements including increased adipokine levels, insulin resistance, inflammation and progressive catabolism. It is not known whether metabolic dysfunction and adipocyte activation worsen in the setting of acute clinical decompensation, or conversely, improve with clinical recovery.
Testing equality of ratios from two finite populations

Abstract Approximations are given for the bias and variance of both the regression and ratio estimator when sampling from a finite population, and simulation results are given indicating the accuracy of the approximations and the bias of the estimated approximations. A different estimator for the variance of the regression estimator is recommended. Test procedures are proposed for testing the hypothesis of equality of ratios from two finite populations, the procedures depending upon the types of populations being sampled. Simulation results indicating the effectiveness of the test procedures in controlling their size are given.
Enlightened semantics for simple sentences

According to Helene Cixous, as interpreted by Nye (1996: 327), 'semantics is not a neutral analysis, it corresponds to power relations in the real world, relations that are maintained by force, a force applied by grammarians, linguists, and philosophers, as well as by police and armies'. Be that as it may, I would like to expand upon my quasi-Fregean account in Forbes 1997 of the examples in Saul 1997a of apparent substitution-failure (SF) in apparently extensional contexts. Saul observes that there is an intuition of SF in connection with such an example as
The use and misuse of pure water PVT properties for lake waters

ALTHOUGH dissolved substances affect the thermodynamic properties of lake waters,1,2 many limnologists still consider lake water as pure water3–8. This can be a good assumption if used with caution: lake water is by no means pure water, especially when the precise pressure, volume, temperature (PVT) properties are considered. PVT properties of lake water can be determined from an equation of state for sea water provided that the total mass fraction of dissolved salts in seawater and lake water are equated9. In addition, the total mass fraction of dissolved salts affects calculations concerning the temperature of maximum density and thus stability10. Therefore, in the absence of direct PVT measurements on a particular lake, it is at present most appropriate to use an equation of state for seawater when examining effects of PVT properties in lakes. We present here a short equation of state determined with a precision of 2 × 10−6 g cm−3 in density over the appropriate range for most fresh water lakes, 0–0.6‰ salinity, 0–30 °C, and 0–180 bar. The equation of state is based on the 1 atm pure water density and compressibility equations of Kell11, the pure water temperature and pressure effects of Fine and Millero12, and the effects of dissolved salts of Millero et al.13 and Chen and Millero14: where dp and d0 are the densities of lake water at applied pressures P and 0 (sea level), respectively, t is the temperature in °C, S(‰) is the salinity: where gT is the total grams of dissolved salt in 1 kg of lake water15. The values of gT usually increase with depth due to the increase of HCO3−, Ca2+ and nutrients16. The small changes in composition in a lake can be accounted for by making the appropriate changes in gt. Further, Millero9 and Millero et al.17 showed that the densities calculated from the seawater equation of state for Lake Tanganyika water and artificial river water agree with the measured values to within ±2×10−6g cm−3 despite the large composition difference between the two waters. This verifies the validity of our equation of state for fresh waters.
Human chromosome uncoiling and dissociation

Summary The treatment of human chromosomes with solutions of low ionic strength produces changes in their characteristic morphology, in particular a 0.01 M solution of KCl produces uncoiling of the primary coils of the chromosome; and when the metaphase cells are allowed to rupture by air drying without fixation, the uncoiled chromosomes will dissociate into their constituent longitudinal subunits. The action of the monovalent salt KC1 is reduced in the presence of the divalent salts CaCl2 or MgCl2; and if the proper balance between the divalent and monovalent salts is maintained, the uncoiling and dissociation of the chromosomes is entirely prevented. The multistranded nature of the human chromosome as seen after treatment with the 0.01 M-KCl can be related to the structure of the chromosome as seen with the electron microscope and to the structure of chromosomes from other species where their study has been somewhat easier.
Electroporation of exogenous antigen into the cytosol for antigen processing and class I major histocompatibility complex (MHC) presentation: weak base amines and hypothermia (18°C) inhibit the class I MHC processing pathway

While endogenous antigens are presented by class I major histocompatibility complex (MHC) molecules, exogenous antigens generally require a means for penetration into the cytosol for processing prior to class I MHC presentation. We have optimized conditions for electroporation as a means to experimentally introduce exogenous antigens into the cytosol, providing a system with a number of advantages for dissecting the class I MHC processing pathway. Presentation was assessed by the response of class I or class II MHC-restricted T hybridoma cells. Essentially instantaneous antigen delivery by electroporation facilitated kinetic analysis of the class I pathway and investigation of the effects of various inhibitors or hypothermic conditions on class I MHC antigen processing. This pathway was inhibited by weak base amines (e.g. chloroquine and NH4Cl), cycloheximide, and hypothermia (18 degrees C, which inhibits certain intracellular vesicular processing pathways). The electroporation technique provides a simple, consistent approach for rapid cytosolic antigen delivery for analysis of class I MHC processing.
Biomechanical comparison of parallel versus 90-90 plating of bicolumn distal humerus fractures with intra-articular comminution.

Purpose To compare the biomechanical properties of 90-90 versus mediolateral parallel plating of C-3 bicolumn distal humerus factures. Methods We created intra-articular AO/Orthopaedic Trauma Association C-3 bicolumn fractures in 10 fresh-frozen matched pairs of cadaveric elbows. We determined bone mineral density of the metaphyseal region with dual-energy x-ray absorptiometry. The matched pairs of elbows were randomly assigned to either 90-90 or parallel plate fixation. We tested anteroposterior displacement at a rate of 0.5 mm/s to a maximum load of ±100 N for both the articular and entire distal humerus segments. We tested torsional stability at a displacement rate of 0.1 Hz to a maximum torque of ±2.5 Nm. After cyclical testing, we loaded the specimens in torsion to failure. Results There was no significant difference in the bone density of the paired specimens. Compared with parallel fixation, 90-90 plate fixation had significantly greater torque to failure load. Both plating constructs were equally sensitive to bone density. Both techniques had the same mode of failure in torsion, a spiral fracture extending from the medial plate at the metaphyseal-diaphyseal junction. There was no significant difference in the stiffness of fixation of the articular fragment or the entire distal segment in anteroposterior loading. Conclusions This study demonstrated that 90-90 and parallel plating had comparable biomechanical properties for fixation of comminuted intra-articular distal humerus fractures, and that 90-90 plating had greater resistance to torsional loading.
Mechanical activities of trachea as measured in vitro and in vivo.

Abstract The phenomenon of spontaneous contractions as measured in vivo and in vitro (isolated guinea pig trachea) is described. Invitro contractility is defined in terms of active tension (AT), the maximum rate of tension development (dT/dt) and time to peak tension (TTP). The length-tension relationship was established for spontaneous contractions of isolated guinea pig trachea. The effect of the temperature on spontaneous activities was also studied. An increase in temperature from 37.5 to 41.5 °c produced an increase in the maximum rate of tension development (dT/dt) and a decrease in the time to peak tension (TTP). A comparable decrease in temperature, from 37.5 to 33.5 °c produced slight but not statistically significant increases in active tension, dT/dt and TTP. Frequency of the spontaneous contractions varied directly with changes in temperature. Employing a micro-strain-gauge transducer a rhytmic change of trachea! diameter has been observed in vivo in both guinea pigs and rabbits. Administration of atropine and isoproterenol in those experiments transiently abolished the appearance of these rhythmic changes of tracheal diameter.
Occurrence of the Kumamoto oyster Crassostrea sikamea in the Ariake Sea, Japan

The Kumamoto oyster Crassostrea sikamea is distinguished from the closely related Pacific oyster C. gigas by concordant differences in 16S rDNA, allozymes, and a one-way gametic incompatibility. After repeated failures to find this oyster in its native habitat, we speculated in 1994 that “the Kumamoto oyster may be extinct in Japan”. In September 1996, we sampled small, deep-cupped oysters from the Ariake Sea and typed these for 16S rDNA and ITS-1 DNA markers previously shown to be diagnostic for the three most common oysters in the Ariake Sea, C. gigas, C. sikamea and C. ariakensis. Our earlier suggestion of the demise of C. sikamea proved incorrect. Of the 256 oysters sampled, 181 (71%) were C. gigas, 53 (21%) were C. sikamea, and 22 (9%) were C. ariakensis; no interspecific hybrids were observed. The distributions of C. sikamea and C. ariakensis are clumped in the Ariake Sea: C. sikamea occurs on the eastern and northern shores, C. ariakensis occurs only in the northern part. These results emphasize the value of molecular markers for discriminating these morphologically plastic species both in the field and in aquaculture.
State Banks and the National Banking Acts: Measuring the Response to Increased Financial Regulation, 1860–1870

The National Banking Acts and their supporting legislation led to 263 state bank closures and 934 charter conversions between 1863 and 1870. This paper measures and analyzes these sudden changes using the period's first complete bank-level census. The data suggest that the national capital requirements prevented many existing banks from converting to a national charter, whereas a tax on state bank notes was responsible for the large number of closures. The legislation also prevented new national banks from replacing closed state banks and, instead, encouraged note and security brokers to open new banks in developing areas along the Manufacturing Belt.
Interaction of Methyl-substituted Borazines with Various Acceptor Molecules

IT has been suggested that borazines might be expected to form molecular complexes with electron-pair acceptors1, and interactions between hexamethylborazine and tetra-cyanoethylene2 or iodine3 have been reported. In further support of this suggestion we wish to report the initial results of a spectrophotometric investigation of the interaction between methyl-substituted borazines and some acceptor molecules. Solutions of B-trimethyl-, B-trimethyl-N-methyl-, B-trimethyl-N-dimethyl-, and hexa-methyl-borazine in carbon tetrachloride and in n-heptane exhibit featureless absorption spectra in the range 600–200 mµ, but the spectra of mixtures containing these borazines and typical acceptor molecules in the same solvents exhibit bands which are not characteristic of the acceptors. (See Table 1 for some representative data.)
Display of myocardial motion by projecting specific components of the 3D motion of myocardial elements on the plane of origin

Abstract The analysis and display of myocardial kinetics is generally based on a-priori assumptions about the direction of the myocardial displacement (centripetal–centrifugal) and about the identity of the myocardial segment moving along that direction. In addition, many displays are slice displays, in which the displacement of myocardial segments between slices is not taken into account. The purpose of this study was to devise an analytical tool in which the motion of myocardial elements in 3D space can be measured and then represented as projection on the original location plane, therefore eliminating artifacts from off-plane motion. Furthermore, components of the motion vectors can be reanalyzed a posteriori, e.g. for centripetal–fugal and torsion.
Keeping assessment local: The case for accountability through formative assessment

Abstract This paper discusses the method, results, and implications of a study of undergraduate student writing at a large, diverse research university, and makes the case for grounding substantive writing assessment in local stakeholders and formative design. Data were collected from multiple sources: writing samples obtained from courses across disciplines, faculty descriptions of the assignments behind the samples, survey data reporting what faculty expect and observe in student writing, and survey data representing the writing-related attitudes and behaviors of students. Analyses included scoring samples against a rubric, exploratory factor analysis, and regression analysis. Discussion focuses on the design, stakeholder and philosophical issues that determine the utility and impact of the results of a writing assessment, particularly as accountability pressure increases.
Protecting Cryptographic Keys from Memory Disclosure Attacks

Cryptography has become an indispensable mechanism for securing systems, communications and applications. While offering strong protection, cryptography makes the assumption that cryptographic keys are kept absolutely secret. In general this assumption is very difficult to guarantee in real life because computers may be compromised relatively easily. In this paper we investigate a class of attacks, which exploit memory disclosure vulnerabilities to expose cryptographic keys. We demonstrate that the threat is real by formulating an attack that exposed the private key of an OpenSSH server within 1 minute, and exposed the private key of an Apache HTTP server within 5 minutes. We propose a set of techniques to address such attacks. Experimental results show that our techniques are efficient (i.e., imposing no performance penalty) and effective - unless a large portion of allocated memory is disclosed.
Molecular Cloning of Five β-Glucosidases from Four Species of Higher Termites (Blattodea: Termitidae)

Cellulose is the most abundant polymer in the biosphere, and termites are one of the most important metazoan cellulose processors. Termites are a rich source of digestive enzymes such as endo- β-1,4-glucanases, β-glucosidases, xylanases, amylases, pectinases, and laccases, regardless of whether they are termite derived or of microbiotic origin. Molecular identification of the termite's digestive enzyme is a critical initial step toward using termites as bioresources for industrial applications. Here, we report five β-glucosidase sequences obtained from four species of higher termites (Anoplotermes schwarzi Banks, Macrotermes carbonarius (Hagen), Rhynchotermes bulbinasus Scheffrahn, Sphaerotermes sphaerothorax (Sjoestedt)) with differing nutritional biologies. The deduced amino acid sequences indicated that they were most similar to β-glucosidases in the glycosyl hydrolase family 1 (GHF1). All complete coding sequences are 490 amino acids long and contain conserved motifs involved in substrate binding and catalysis. Each sequence was also predicted to be glycosylated at two sites.
The ‘Lower Perigordian’ in French Archaeology.

An evaluation of the concept of ‘Lower Perigordian‘ is attempted in this paper. The conclusion of this work suggests that the Lower Perigordian is a fallacious concept, that it can no longer be accepted as the first stage of the French Upper Palaeolithic, and that the so-called Lower Perigordian stone industries may not even represent a unified stage in the development of stone-tool technology.The terms ‘industry’ and ‘assemblage’ will be used in this paper in the sense defined by Braidwood (1946, 133–6). An industry is a collection of tools of one category of material (here stone or bone only) which appears in archaeological context, or in an untransported geological context. An assemblage is ‘… a variety of categories of artifacts and non-artifactual materials which appears in archaeological context.’ The non-artifactual aspect of an assemblage most notably provides information on geological context and physical relationships. Many of the collections of tools to be dealt with below can in no way be considered assemblages, but we still know something of their archaeological contexts, so they have not yet sunk to the level of Braidwood's ‘aggregations’. ‘Culture’ will be used in its anthropological sense to mean the whole of patterned, learned behaviour shared by a group of human beings, and the effects of this behaviour on material artifacts. If set off by quotation marks, ‘culture’ may refer also to the ‘material culture’ of other writers or be a convenient translation of the French word ‘civilization.’
Identity and interaction: a sociocultural linguistic approach

The article proposes a framework for the analysis of identity as produced in linguistic interaction, based on the following principles: (1) identity is the product rather than the source of linguis...
Real Versus Imagined Gender Harassment

Sexual harassment studies that use hypothetical situations and retrospective surveys may overestimate the degree to which victims actually confront their harassers. The result is that immediate emotional reactions are little understood and victims are often taken to task for nonconfrontational behavior. To address this neglect, we describe our experimental investigation of immediate reactions to sexually harassing questions encountered during a realistic job interview. Behavioral and emotional responses are compared to those in an imagined harassing interview. Results indicate that interviewees who are actually harassed react very differently than those who only imagine their responses. For example, imagined victims anticipate feeling angry but actual targets report being afraid. Anticipated behavior also did not mesh with actual behavior. Implications of these discrepancies for perceptions of “correct” ways to respond to harassment are examined.
Using natural language and stereotypical knowledge for acquisition of software models

The MOANA (model acquisition using natural-language) system is described. It uses a natural language dialog with the user to acquire formal software requirements. These requirements are represented in a number of modeling formalisms including graphical data-flow models and function models. In order to understand the user, MOANA uses knowledge about the structure and requirements of typical software systems. This knowledge is represented as a number of stereotypical software models. In a comparison of the software models produced by MOANA and those produced by a human software engineer, the MOANA models tend to be much more complete. >
Estimating the treatment effect in the two-sample problem with auxiliary information

In this paper, we apply the empirical likelihood method to find estimates and confidence intervals for the treatment effect in the two-sample problem. These estimates and confidence intervals make use of auxiliary information about a control group. A simulation study is presented to assess the finite sample performance of the proposed estimates.