cssi/SciSciGPT-SciSciNet huggingface dataset:
Dissolution and initial hydration behavior of tricalcium aluminate in low activity sulfate solutions

Abstract Influences of alkali or alkaline earth sulfates on the hydration of cubic tricalcium aluminate (C3A) were evaluated by in situ dissolution rate measurements, by ex situ near-surface composition measurements with secondary ion mass spectrometry, and by in situ synchrotron X-ray diffraction to monitor precipitation of hydration products. Both slight reductions in dissolution rate and cation-specific interactions with the solid were observed. The near-surface Ca/Al ratio is significantly lower after some dissolution and the electrolyte cations are incorporated within the surface with different affinities (Mg2+ > K+ > Na+). An interfacial dissolution-reprecipitation mechanism may explain the observations as well as, or better than, a simple cation exchange. The sulfate concentration in solution affects the rates of both C3A dissolution and precipitation of hydration products. Sulfate ions likely adsorb at the hydrous Al-rich surface layer, thereby reducing the dissolution rate of aluminates and delaying the precipitation of aluminate hydration products.
Laboratory Evaluation of Effect of Addition Methods of Rejuvenators on Properties of Recycled Asphalt Mixtures

AbstractThe objective of this study was to compare the effectiveness of rejuvenators and determine how the methods of adding rejuvenators into recycled asphalt mixtures could affect their performan...
Secondary Narcolepsy in Children

Secondary narcolepsy occurs as a consequence of lesions involving the hypothalamic region that subserve wakefulness. Although observations on the characteristics of secondary narcolepsy have been published in adults, information on this topic in children is sparse. This is a retrospective study of characteristics and outcome of secondary narcolepsy in children. The medical records of 10 children with this condition at Mayo Clinic, Rochester, were reviewed. Characteristics of the underlying neurologic disorder, narcolepsy subtype, multiple sleep latency tests, medications used and outcome were extracted. Age at diagnosis of narcolepsy was between 6 and 17 years. Five of 10 patients had onset of excessive sleepiness within 1 year of diagnosis of the primary neurologic disorder. Six of 10 patients had type 1 narcolepsy (with cataplexy) whereas 4/10 had type 2 (without cataplexy). The clinical course was variable, with 8/10 continuing to require treatment for sleepiness at a mean period 6.6±6.2 years after diagnosis. One patient with narcolepsy type 1 due to Niemann Pick type C disease had died. One patient with narcolepsy type 2 due to craniopharyngioma had spontaneous remission of sleepiness. The 5/10 patients surviving with narcolepsy type 1 have continued to require pharmacotherapy for both sleepiness and cataplexy. This study draws attention to an important chronic sequel of childhood brain lesions that has variable, etiology-specific outcome. The rare occurrence of spontaneous resolution of childhood narcolepsy symptoms, not previously described, is also discussed.
Transfer learning for decision support in Covid-19 detection from a few images in big data

The novel coronavirus (Covid-19) has spread rapidly amongst countries all around the globe. Compared to the rise in cases, there are few Covid-19 testing kits available. Due to the lack of testing kits for the public, it is useful to implement an automated AI-based E-health decision support system as a potential alternative method for Covid-19 detection. As per medical examinations, the symptoms of Covid-19 could be somewhat analogous to those of pneumonia, though certainly not identical. Considering the enormous number of cases of Covid-19 and pneumonia, and the complexity of the related images stored, the data pertaining to this problem of automated detection constitutes big data. With rapid advancements in medical imaging, the development of intelligent predictive and diagnostic tools have also increased at a rapid rate. Data mining and machine learning techniques are widely accepted to aid medical diagnosis. In this paper, a huge data set of X-ray images from patients with common bacterial pneumonia, confirmed Covid-19 disease, and normal healthy cases are utilized for AI-based decision support in detecting the Coronavirus disease. The transfer learning approach, which enables us to learn from a smaller set of samples in a problem and transfer the discovered knowledge to a larger data set, is employed in this study. We consider transfer learning using three different models that are pre-trained on several images from the ImageNet source. The models deployed here are VGG16, VGG19, and ResNet101. The dataset is generated by gathering different classes of images. We present our approach and preliminary evaluation results in this paper. We also discuss applications and open issues.
Differences in Clinician Electronic Health Record Use Across Adult and Pediatric Primary Care Specialties.

Clinicians spend a large proportion of their days using the electronic health record (EHR). There are known negative associations between measures of EHR use and clinician experience.1 Primary care clinicians spend significantly more total and after-hours time in the EHR than medical specialty and surgical colleagues.2 However, little is known regarding variation in EHR use across primary care specialties, such as between adult and pediatric care. In this cross-sectional study, we compared EHR use across general pediatrics, general internal medicine, and family medicine clinicians.
Wiring Damage Analyses for Sts Ov-103

This study investigated the Shuttle Program s belief that Space Transportation System (STS) wiring damage occurrences are random, that is, a constant occurrence rate. Using Problem Reporting and Corrective Action (PRACA)-derived data for STS Space Shuttle OV-103, wiring damage was observed to increase over the vehicle s life. Causal factors could include wiring physical deterioration, maintenance and inspection induced damage, and inspection process changes resulting in more damage events being reported. Induced damage effects cannot be resolved with existent data. Growth analysis (using Crow-AMSAA, or CA) resolved maintenance/inspection effects (e.g., heightened awareness) on all wire damages and indicated an overall increase since Challenger Return-to-Flight (RTF). An increasing failure or occurrence rate per flight cycle was seen for each wire damage mode; these (individual) rates were not affected by inspection process effects, within statistical error.
Photoluminescence in Zn 1-x Co x Se under hydrostatic pressure

We report on low temperature measurements of the pressure dependence of the photoluminescence (PL) associated with ${\mathrm{Co}}^{2+}$ in ZnSe performed in a diamond anvil cell. Two sharp emission peaks at \ensuremath{\sim}2.36 eV, labeled L and ${\mathit{L}}^{\ensuremath{'}}$, show a weak redshift under pressure with rapidly decreasing peak intensities. These results, together with the excitation energy and temperature dependence of the PL at 1 bar, allow for a critical examination of previous models proposed for these optical transitions. The PL data are discussed within the framework of conventional crystal-field theory based on the Racah and crystal-field parameters B, C, and \ensuremath{\Delta}(=10Dq). From this analysis, the normalized energy E/B is determined as a function of the normalized crystal field parameter Dq/B. Thus quantitative estimates for the enhancement in the p-d hybridization with pressure (evident in the line-shape profiles of the spectra) are deduced. The energy separation between L and ${\mathit{L}}^{\ensuremath{'}}$ decreases continuously for modest pressures (\ensuremath{\sim}1 GPa), and raises questions about the role of spin-orbit coupling in accounting for the splitting of this emission doublet. \textcopyright{} 1996 The American Physical Society.
Feminism for the mainstream criminologist: An invitation

Abstract Feminism has historically been peripheral to the study and practice of criminal justice; mainstream criminologists have not been widely exposed to feminist perspectives. This has contributed to perceptions that criminology is about men and feminism is only about women. Consequently, many criminologists and criminal justice practitioners have yet to understand, much less appreciate, the importance of feminism's contribution to criminology. To address this problem, this article explains some of the major feminist insights in the interrelated areas of epistemology, theory, methodology, and policy. Examples from the criminal justice literature are used to illustrate both the basis for feminist concerns as well as the diversity of feminist scholarship.
The Debate over Species Concepts and Its Implications for Ornithology

We review recent developments in the debate over species concepts, exploring differences between the biological species concept (BSC) and the phylogenetic species concept (PSC). Three principal flaws in the BSC are reviewed: (1) the occurrence of paraphyletic or nonhistorical groups; (2) the misrepresention of the significance of hybridization among differentiated taxa; and (3) the logical difficulty in handling allopatric populations. Simple cline theory shows that likely times to fusion for hybridizing taxa exceed the average duration of most species in the fossil record. We address criticisms of PSCs (of which there are several), including the application of phylogenetic methods to populations, and whether species can be monophyletic. We suggest that the evolutionary species concept and the PSC might be more similar than generally appreciated. Empirical studies of variation in the Brown Towhee (Pipilo fuscus) complex and Fox Sparrow (Passerella iliaca) reveal that the BSC and PSC can lead to different species limits. Reasons are given for why the PSC is the preferred concept for comparative biology, phylogenetic inference, historical biogeography, estimation of bio- diversity, hybrid-zone analysis, conservation biology, and speciation analysis. Despite prob- lems associated with all species concepts, we think that a concept consistent with the PSC should replace "biological" species concepts. Received 12 April 1994, accepted 4 November 1994.
The Effects of Strategic and Structural Supply Chain Orientation on Operational and Customer‐Focused Performance

Supply chain orientation (SCO), or the implementation of a supply chain management philosophy, consists of two distinct, yet interdependent elements, namely strategic SCO and structural SCO. Strategic SCO involves integrating an SCM philosophy into the firm's strategy development, while structural SCO encompasses operational-level behaviors and actions that reflect such a philosophy. This study extends the research on SCO by developing hypotheses on the contingent effects of strategic SCO and structural SCO on a firm's operational and customer-focused performance. Drawing on the strategy-structure-performance framework, the study proposes that strategic SCO and structural SCO positively affect different dimensions of performance and that structural SCO plays a mediating role in the relationship between strategic SCO and performance. These relationships are tested using primary survey data and archival data from 183 manufacturers in the Midwestern US. Results confirm that strategic SCO is associated with both operational performance and customer-focused performance, but structural SCO is only related to operational performance. Structural SCO acts as a mediator in linking strategic SCO with operational performance and customer-focused performance and mediation effects are strengthened at higher levels of environmental dynamism.
Fluorescence microscopy in three dimensions.

The combination of the specificity provided by fluorescence microscopy and the ability to quantitatively analyze specimens in three dimensions allows the fundamental organization of cells to be probed as never before. Key features in this emergent technology have been the development of a wide variety of fluorescent dyes or fluorescently labeled probes to provide the requisite specificity. High-quality, cooled charge-coupled devices have recently become available. Functioning as nearly ideal imagers or "electronic film," they are more sensitive than photomultipliers and provide extraordinarily accurate direct digital readout from the microscope. Not only is this precision crucial for accurate quantitative imaging such as that required for the ratioing necessary to determine intracellular ion concentrations, but it also opens the way for sophisticated image processing. It is important to realize that image processing isn't simply a means to improve image aesthetics, but can directly provide new, biologically important information. The impact of modern video microscopy techniques (Allen, 1985; Inoue, 1986) attests to the fact that many biologically relevant phenomena take place at the limits of conventional microscopy. Image processing can be used to substantially enhance the resolution and contrast obtainable in two dimensions, enabling the invisible to be seen and quantitated. Cells are intrinsically three-dimensional. This can simply be a nuisance because of limited depth of focus of the microscope or it could be a fundamental aspect of the problem being studied. In either case, image processing techniques can be used to rapidly provide the desired representation of the data. In this chapter we have discussed the nature of image formation in three dimensions and dealt with several means to remove contaminating out-of-focus information. The most straightforward of these methods uses only information from adjacent focal planes to correct the central one. This approach can be readily applied to virtually any problem and with most commonly available image processing hardware to provide a substantially deblurred image in almost real time. In addition to covering more sophisticated algorithms where the utmost in three-dimensional imaging is required, we have developed a method for extremely rapidly and accurately producing an in-focus, high-resolution "synthetic projection" image from a thick specimen. This is equivalent to that produced by a microscope having the impossible combination of a high-NA objective lens and an infinite depth of focus. A variation on this method allows efficient calculation of stereo pairs.(ABSTRACT TRUNCATED AT 400 WORDS)
Anomalous Absorption of Intense Radiation

Anomalous heating of a plasma by an electric field oscillating near the plasma frequency is considered. The large field excites the oscillating two-stream and the ion-acoustic decay instabilities. Numerical simulation of these instabilities has confirmed the linear theory for their growth and has shown that when the instabilities saturate a strong anomalous heating occurs. This heating results in the production of energetic electrons. A simple nonlinear theory gives results in reasonable agreement with the numerical calculations. These predictions could be applied to laboratory experiments.
Recovery mechanisms in database systems

From the Publisher: This is the first book to bring together all you need to know about database recovery - both theory and practice. It covers not just recovery mechanisms in today's relational databases, but also the critically important new techniques for main memory databases, mobile computing, and enterprise workflow systems. Recovery Mechanisms in Database Systems will be an essential resource for all database designers, architects, decision-makers, and advanced students in the field.
F/M-CIP: implementing flash memory cache using conservative insertion and promotion

Flash memory SSD has emerged as a promising storage media and fits naturally as a cache between the system RAM and the disk due to its performance/cost characteristics. Managing such an SSD cache is challenging and traditional cache replacements do not work well because of SSDs asymmetric read/write performances and wearing issues. This paper presents a new cache replacement algorithm referred to as F/M-CIP that accelerates disk I/O greatly. The idea is dividing the traditional LRU list into 4 parts: candidate-list, SSD-list, RAM-list and eviction-buffer-list. Upon a cache miss, the metadata of the missed block is conservatively inserted into the candidate-list but the data itself is not cached. The block in the candidate-list is then conservatively promoted to the RAM-list upon the k-th miss. At the bottom of the RAM-list, the eviction-buffer accumulates LRU blocks to be written into the SSD cache in batches to exploit the internal parallelism of SSD. The SSD-list is managed using a combination of recency and frequency replacement policies by means of conservative promotion upon hits. To quantitatively evaluate the performance of F/M-CIP, a prototype has been built on Linux kernel at the generic block layer. Experimental results on standard benchmarks and real world traces have shown that F/M-CIP accelerates disk I/O performance up to an order of magnitude compared to the traditional hard disk storage and up to a factor of 3 compared to the traditional SSD cache algorithm in terms of application execution time. Furthermore, F/M-CIP substantially reduces write operations to the SSD implying prolonged durability.
Scaling property of the Koch fractal dipole

The increased interest in fractal antennas is due to their possible application in multi-band wireless communication devices. The fractal antenna is formed by applying a generator shape repetitively at a constant scale factor and results in an antenna with log-periodic characteristics. By utilizing the selfsimilar nature of the fractal shape, one can develop some fast approximation techniques.
Chemokine receptors in asthma: searching for the correct immune targets.

The overall incidence, severity, and prevalence of asthma has risen dramatically with a distressing increase in children ([1][1]). Asthmatics are presently treated with nonspecific inhibitors of the inflammatory responses using inhaled or oral steroids accompanied by bronchodilating reagents but the
Binding of [3H]estradiol by brain cell nuclei and female rat sexual behavior: inhibition by experimental diabetes

In streptozotocin-diabetic female rats acute (24 h) withdrawal of insulin significantly impairs both estradiol+progesterone-induced sexual receptivity and cell nuclear concentration of [3H]estradiol in hypothalamus, preoptic area, and pituitary gland. Omission of insulin treatment for the first 24 h of a 30-h or 54-h estradiol benzoate-conditioning period significantly reduced mean lordosis ratings of ovariectomized-diabetic rats. Insulin withdrawal at the time of progesterone treatment and behavioral testing did not diminish sexual receptivity. One-half or 2 h after an intravenous injection of [3H]estradiol-17β diabetic rats without insulin exhibited reduced cell nuclear [3H]estradiol concentrations (2 h) and/or diminished cell nuclear/whole homogenate concentration ratios (0.5 and 2 h). Twenty-four hour insulin withdrawal affected neither whole tissue [3H]estradiol uptake nor hypothalamus-preoptic area cytoplasmic estrogen-receptor content. These results: (1) suggest that diminished estradiol binding by target tissue cell nuclei may contribute to the well-known reproductive failures of female diabetics, and (2) support the concept that estradiol acts at the level of brain cell nuclei to induce female sexual behavior.
Chain-Selective Isotopic Labeling for NMR Studies of Large Multimeric Proteins: Application to Hemoglobin

Multidimensional, multinuclear NMR has the potential to elucidate the mechanisms of allostery and cooperativity in multimeric proteins under near-physiological conditions. However, NMR studies of proteins made up of non-equivalent subunits face the problem of severe resonance overlap, which can prevent the unambiguous assignment of resonances, a necessary step in interpreting the spectra. We report the application of a chain-selective labeling technique, in which one type of subunit is labeled at a time, to carbonmonoxy-hemoglobin A (HbCO A). This labeling method can be used to extend previous resonance assignments of key amino acid residues, which are important to the physiological function of hemoglobin. Among these amino acid residues are the surface histidyls, which account for the majority of the Bohr effect. In the present work, we report the results of two-dimensional heteronuclear multiple quantum coherence (HMQC) experiments performed on recombinant (15)N-labeled HbCO A. In addition to the C2-proton (H epsilon(1)) chemical shifts, these spectra also reveal the corresponding C4-proton (H delta(2)) resonances, correlated with the N epsilon(2) and N delta(1) chemical shifts of all 13 surface histidines per alpha beta dimer. The HMQC spectrum also allows the assignment of the H delta(1), H epsilon(1), and N epsilon(1) resonances of all three tryptophan residues per alpha beta dimer in HbCO A. These results indicate that heteronuclear NMR, used with chain-selective isotopic labeling, can provide resonance assignments of key regions in large, multimeric proteins, suggesting an approach to elucidating the solution structure of hemoglobin, a protein with molecular weight 64.5 kDa.
Illegal drugs, policy change, and state power: The case of contemporary China

This article describes and analyzes the rapid resurgence of illegal drugs in contemporary China since the late 1970s. It also examines the evolution and implementation of China's anti‐narcotic policy, especially the people's war on drugs launched in 1990. It is suggested that the resurgence of drug trafficking and drug abuse provides additional evidence of the severe erosion of regime legitimacy in China
Classical and Bootstrap Estimates of Heritability of Milk Yield in Zimbabwean Holstein Cows

Abstract The h 2 of first lactation milk yield in Zimbabwean grade Holstein cows was estimated as the regression of daughter on the dams' adjusted milk yield, using least squares, least absolute value, bootstrap restricted least squares, and bootstrap restricted least absolute value estimators. The estimators were evaluated for efficiency and robustness in estimating h 2 . The estimated h 2 were .272, .265, .283, and .290 by least squares, least absolute value, bootstrap restricted least squares, and bootstrap restricted least absolute value procedures, respectively. The classic 90% confidence intervals for h 2 were .030 to .514 by least squares and .056 to .474 by least absolute value procedures. The bootstrap restricted least squares 90% confidence interval for h 2 was .000 to .542, and the bootstrap restricted least absolute value 90% confidence interval was .000 to .615. The point estimates by the four procedures were comparable, but the bootstrap confidence intervals were more conservative than their classic counterparts. The least absolute value estimator was the most efficient and the second best in robustness. The least squares estimator was second best in efficiency and worst in robustness. The bootstrap restricted least absolute value estimator was the least efficient and the second best in robustness.
TWO APPROACHES TO SCHOOL DESEGREGATION AND THEIR IMPACTS ON CITY‐SUBURBAN CHOICE: Cincinnati, Ohio, and Wilmington, Delaware

: This paper employs step wise multiple regression to test the effectiveness of combined city-suburban school districts in increasing the willingness of families with children to choose central city locations. Over 5000 recent homebuyers in Hamilton County (Cincinnati), Ohio, and New Castle County (Wilmington), Delaware, were surveyed. New Castle County had combined city-suburban school districts and families living there were expected to be more likely to choose the central city when all other relevant characteristics were controlled. Just the opposite occurred. Hamilton County buyers were more likely to choose the city, reflecting the greater variety of attractive middle income neighborhoods within the City of Cincinnati. It is suggested that efforts to attract middle income families to cities should focus on maintaining the quality of the older housing stock and on improving neighborhood business districts. Additional research is needed on the impact of different school desegregation schemes on location choices.
Field-induced lead zirconate titanate stannate antiferroelectric-to-ferroelectric phase-switching ceramics

The electric field induced antiferroelectric-to-ferroelectric phase transition of lead zirconate titanate stannate ceramics was investigated by means of dielectric, polarization, and strain hysteresis measurements. Compositions of varying titanium and tin within the general formula (Pb0.98La0.02) (Zr0.66Ti0.11-xSn0.23+x)O3, located in the tetragonal antiferroelectric phase field and near the ferroelectric rhombohedral boundary were prepared. As the applied electric field increased, a sudden increase in both longitudinal and transverse strain was observed with a corresponding change in dielectric constant, loss, and polarization, indicating the transition from antiferroelectric to ferroelectric phase. The longitudinal strain increased continuously into the ferroelectric phase, whereas the transverse strain became negative after the phase change. By defining the phase change field from polarization and high field dielectric constant and loss measurements, the longitudinal strains associated with the phase change for all of the compositions were less than 0.2%. For some compositions, however, the longitudinal strain increased to levels greater than 0.5% with increasing applied field. Owing to the relatively small decrease in transverse strain in the ferroelectric region, the volume strain continued to increase even after antiferroelectric to ferroelectric phase change.
An Overview of the Direct Energy Conversion Proof of Principle Power Production Program

The United States Department of Energy, Nuclear Energy Research Initiative (NERI) Direct Energy Conversion Proof of Principle (DECPOP) project has as its goal the development of a direct energy conversion process suitable for commercial development. We define direct energy conversion as any fission process that returns usable energy without an intermediate thermal process. A prior Direct Energy Conversion (DEC) project [1] has been completed and indicates that a viable direct energy device is possible if several technological issues can be overcome. The DECPOP program is focusing on two of the issues: charged particle steering and high voltage hold-off. This paper reports on the progress of the DECPOP project. Two prototype concepts are under development: a Fission Electric Cell using magnetic insulation and a Fission Fragment Magnetic Collimator using magnetic fields to direct fission fragments to collectors. Included in this paper are a short project description, an abbreviated summary of the work completed to date, a description of ongoing and future project activities, and a discussion of the potential for future research and development.Copyright © 2004 by ASME
II.—The Principle of Saturation in Petrography: A Reply

In exercising a debater's right to reply to criticism, I shall be extremely brief. My contentions, in two essays on the above subject,1 were as follows:— 1. That the classification of rocks by silica percentage is unsatis-factory, and that a more natural basis for classification is available in the degree of saturation of the constituent minerals. My critic, Mr. Scott, has not expressed any opinion on this pointof comparison. 2. That the field evidence is overwhelmingly favourable to the separation of the rock minerals into two groups, those of one group being stable in the presence of free silica under magmatic conditions, those of the other group unstable; and that such experimental work as has been done supports that separation.
Spectral multipliers for a distinguished Laplacian on certain groups of exponential growth (A remark on the paper of M. Cowling et al.)

We study spectral multipliers for a distinguished Laplacian on certain groups of exponential growth. We obtain a stronger optimal version of the results proved in (CGHM) and (A).
A multithreaded PowerPC processor for commercial servers

This paper describes the microarchitecture of the RS64 IV, a multithreaded PowerPC® processor, and its memory system. Because this processor is used only in IBM iSeries™ and pSeries™ commercial servers, it is optimized solely for commercial server workloads. Increasing miss rates because of trends in commercial server applications and increasing latency of cache misses because of rapidly increasing clock frequency are having a compounding effect on the portion of execution time that is wasted on cache misses. As a result, several optimizations are included in the processor design to address this problem. The most significant of these is the use of coarse-grained multithreading to enable the processor to perform useful instructions during cache misses. This provides a significant throughput increase while adding less than 5% to the chip area and having very little impact on cycle time. When compared with other performance-improvement techniques, multithreading yields an excellent ratio of performance gain to implementation cost. Second, the miss rate of the L2 cache is reduced by making it four-way associative. Third, the latency of cache-to-cache movement of data is minimized. Fourth, the size of the L1 caches is relatively large. In addition to addressing cache misses, pipeline "holes" caused by branches are minimized with large instruction buffers, large L1 I-cache fetch bandwidth, and optimized resolution of the branch direction. In part, the branches are resolved quickly because of the short but efficient pipeline. To minimize pipeline holes due to data dependencies, the L1 D-cache access is optimized to yield a one-cycle load-to-use penalty.
On the speed of the carotid chemoreceptor response in relation to the kinetics of CO2 hydration.

Abstract The response of the perfused carotid body of the cat to an increase in [H+] and PCO2 was examined during perfusion with bicarbonate Ringer's solution to which the buffer tris and/or an inhibitor of the enzyme carbonic anhydrase were added. Although the theoretical half-time for uncatalyzed CO2 hydration in the presence of 40 mM tris buffer would be 15–20 sec, the responses in impulse frequency during perfusion with tris occurred as rapidly as the responses in the absence of tris, with a half-time for chemoreceptor activation of one second or less, and were too rapid to be accounted for by the uncatalyzed hydration of CO2. Exposure to acetazolamide increased the response half-time by 2.5 sec in the absence of tris, and by 5.1 sec during perfusion with 40 mM tris buffer. The results indicate the presence of carbonic anhydrase activity in carotid body tissue and suggest that the buffering capacity in the environment of the chemoreceptor mechanism is greater than would be expected in extracellular fluid.
A factorization method for identification of Volterra systems

A factorization method is proposed for identification of Volterra systems of order n and analyses the stability of the systems constructed by this method. An optimization method is also suggested to generate optimal systems which minimize system response energy.
Origin of sterols in uredospores of Uromyces phaseoli

Abstract The sterols from healthy bean leaves are β-sitosterol, stigmasterol, campesterol and 28-isofucosterol. An additional sterol observed in bean leaves infected with Uromyces phaseoli was identified as 7,(Z)-24(28)-stigmastadien-3β-ol, which is the major sterol of the uredospores of the fungus. The fungus appears to stimulate sterol synthesis, but most of the increased sterol content of infected leaves can be attributed to the sterol of the uredospores.
NUMERICAL SIMULATION OF SILENCERS

SUMMARY’ The problem of attenuating the noise from weapons firing is studied experimentally and numerically. As a possible method of attenuating the noise significantly, a silencer with no internal baffles is attached to the M242 cannon. The internal pressures inside the muffler are measured. The near-field overpressures outside the muffler at various polar angles are also measured. A numerical simulation of the flow through the muffler is performed, using Harten’s shock-capturing method to solve the Euler equations of ideal compressible flow. The numerical simulation yields a detailed picture of the flow field as displayed by the pressure and Mach contours. Pressuretime curves at selected locations are obtained and compared with experimental data. There is good agreement, except that the numerical simulation generates more vigorous oscillations. The firing of gun weapons often generates objectionable levels of noise. Different methods or combinations of methods can be used to attenuate the noise. One possible response is to develop muzzle devices that attenuate the blast in all directions. These muzzle devices are referred to as noise attenuators, silencers or mufflers and are sometimes used with small-calibre rifles and pistols. Noise attenuators suppress noise from guns by reducing the rate of propellant energy being released to generate the muzzle blast.’-4 No adequate model exists for the flow internal to the muffler; this flow is very complicated and for the larger mufflers is significantly modified by energy transfer of the propellant gases to the body of the muffler. In general, the muffling of the noise increases with the size of the muffling device; attenuation levels up to 40dB have been claimed. However, the weapons producing the objectionable noise may be larger-calibre guns, such as the 25 mm M242 automatic cannon. It is not practical to scale up the noise attenuators designed for small-calibre guns to the size required for the 25 mm cannon, as the added bulk could compromise system performance by making the larger weapon unwieldy. Although mufflers with many bore and chamber volumes have been investigated, work on smaller mufflers has been neglected because generally higher noise attenuation is desired than can be thus achieved. The immediate objective of this study is to adequately simulate a simple small silencer by a particular numerical technique. The flow field inside the silencer during the firing cycle is measured experimentally and also simulated numerically. A total variation diminishing (TVD) shock-capturing scheme is employed, with sufficient grid density to yield the necessary flow detail^.^ Fluid property contours and pressure-time curves at selected locations are generated.
General and Versatile Autoinhibition of PLC Isozymes

Phospholipase C (PLC) isozymes are directly activated by heterotrimeric G proteins and Ras-like GTPases to hydrolyze phosphatidylinositol 4,5-bisphosphate into the second messengers diacylglycerol and inositol 1,4,5-trisphosphate. Although PLCs play central roles in myriad signaling cascades, the molecular details of their activation remain poorly understood. As described here, the crystal structure of PLC-β2 illustrates occlusion of the active site by a loop separating the two halves of the catalytic TIM barrel. Removal of this insertion constitutively activates PLC-β2 without ablating its capacity to be further stimulated by classical G protein modulators. Similar regulation occurs in other PLC members, and a general mechanism of interfacial activation at membranes is presented that provides a unifying framework for PLC activation by diverse stimuli.
Morphology and free volume of nanocomposite Teflon AF 2400 films and their relationship to transport behavior

Abstract Free volume is a key property regulating penetrant (gas phase) or solute (solution phase) permeability in polymeric membranes. Thus, we investigated the origins of free volume in two types of Teflon AF 2400 nanocomposites. In nanocomposites from glassy Teflon AF and fluorophilic, solid silica nanospheres, the soft matrix shows exceptionally high apparent fractional free volume (aFFV P )—reaching over 50% at high particle loading. Adding the higher density FNPs to polymer films actually decreases film density. Nanocomposites from plasticized Teflon AF show similarly high aFFV at high particle loading. However, the nano-scale morphologies of the films are very different. The nanocomposites with glassy polymer exist as a polymer matrix with entrained particles. At higher FNP loadings, where the characteristic distance between particles is smaller than the radius of gyration of the polymer, the polymer exists as a vine-like network entraining the particles. Nanocomposite films with plasticized polymer have a packed, core–shell particle morphology with FNPs as the core and plasticized Teflon AF as the eight-nm shell. While the aFFV P s of the two types of films at high FNP loading are similar, systematic studies reveal different mechanisms for the formation of the apparent free volume elements. Distinctive free volume properties lead to remarkably different transport behavior.
Engaging White College Students in Productive Conversations About Race and Racism: Avoiding Dominant-Culture Projection and Condescension-Judgment Default

Conversations about racism and White privilege are rarely easy, but are necessary in order to have a more equitable society. Through honest and properly facilitated dialogues, people can work through their prejudices toward other people. In this article the author explores two ways in which White preservice educators inadvertently halt classroom conversations about racism.
A gel-scanning method for kinetic studies on an acetylcholinesterase isozyme.

Abstract A gel-scanning technique involving gel staining and spectrophotometric scanning has been developed for quantitative assay of cholinesterase and other esterase isozymes. The kinetics of catalysis and inhibition can be directly determined without elution from the gel.
Dynamical effects in the distribution of helium in the thermosphere

The paper discusses some phenomena, mainly observed by satellites, which illustrate the use of helium as a tracer for studying the morphology and history of atmospheric responses to energy inputs of varying amplitudes and durations. The effects observed include (1) the annual north-south excursion of the sub-solar point producing the winter helium bulge, (2) the 24-hour diurnal variation, where the helium density peak is phase-shifted to the morning in the lower thermosphere, (3) high latitude magnetospheric heating of the thermosphere, with helium indicating regions of probable upwelling of the heated gas, and (4) gravity wave formation and propagation, with the attendant implications for transport of energy from one region of the atmosphere to another.
Attack Robustness and Centrality of Complex Networks

Many complex systems can be described by networks, in which the constituent components are represented by vertices and the connections between the components are represented by edges between the corresponding vertices. A fundamental issue concerning complex networked systems is the robustness of the overall system to the failure of its constituent parts. Since the degree to which a networked system continues to function, as its component parts are degraded, typically depends on the integrity of the underlying network, the question of system robustness can be addressed by analyzing how the network structure changes as vertices are removed. Previous work has considered how the structure of complex networks change as vertices are removed uniformly at random, in decreasing order of their degree, or in decreasing order of their betweenness centrality. Here we extend these studies by investigating the effect on network structure of targeting vertices for removal based on a wider range of non-local measures of potential importance than simply degree or betweenness. We consider the effect of such targeted vertex removal on model networks with different degree distributions, clustering coefficients and assortativity coefficients, and for a variety of empirical networks.
An experimental study of visual imagination and memory

Abstract It is shown that an irrelevant visual perception interferes more with verbal learning by means of imagery than does an irrelevant auditory perception. The relative interfering effects of these perceptions were reversed in a verbal learning task involving highly abstract materials. Such results implicate the existence of a true visual component in imaginal mediation. A theoretical model is presented in which a visual system and a verbal-auditory system are distinguished. The visual system controls visual perception and visual imagination. The verbal-auditory system controls auditory perception, auditory imagination, internal verbal representation, and speech. Attention can be more easily divided between the two systems than within either one taken by itself. Furthermore, the visual and verbal-auditory systems are functionally linked by information recoding operations. The application of mnemonic imagery appears to involve a recoding of initially verbal information into visual form, and then the encoding of a primarily visual schema into memory. During recall, the schema is decoded as a visual image, and then recoded once again into the verbal-auditory system. Evidence for such transformations is provided not only by the interference data, but also by an analysis of recall-errors made by Ss using mnemonic imagery.
Tellurium, a guide to mineral deposits

ABSTRACT Watterson, J.R., Gott, G.B., Neuerburg, G.J., Lakin, H.W. and Cathrall, J.B., 1977. Tellurium, a guide to mineral deposits. J. Geochem. Explor., 8: 31–48. Te dispersion patterns are useful in exploring for different types of mineral deposits and in providing additional information about known ore deposits. The Te content of rocks is given for five mining districts in the western United States: Coeur d'Alene, Idaho; Robinson, near Ely, Nevada; Montezuma, Colorado; Crater Creek area, Colorado; Cripple Creek, Colorado. Many of the analyses were obtained by use of a new analytical method sensitive to 0.001 ppm Te. The principal ore deposits in the Coeur d'Alene district, Idaho, are Pb-Zn-Ag replacement veins in Precambrian rocks of the Belt Supergroup. Te dispersion patterns show the outlines of the original mineral belts, the effects of intrusive events, the location of ore deposits, the displacements caused by post-ore faulting, and the borders of the 780-km 2 district. The disseminated porphyry Cu deposits of the Robinson mining district, Nevada, are associated with Cretaceous quartz monzonite stocks that have intruded Palaeozoic carbonate rocks. Te is present in rock samples in concentrations as high as 10,000 ppm and forms a halo around the areas containing the Cu deposits. The alteration zones in the porphyry Mo district near Montezuma, Colorado, are developed around several small Tertiary intrusions occurring along a regional shear zone. Te haloes reflect the locations of porphyry intrusives, individual deposits and their ore shoots, and the pattern and intensity of adjacent alteration. The Te content of soils over the Montezuma stock is higher than, and varies independently from, the Te content of adjacent outcrops. Soils generally contain more Te than adjacent outcropping rocks. Soil may collect gaseous Te compounds from mineral deposits. The Crater Creek area is a northwestern extension of the Summitville mining district, Colorado. Te dispersion patterns radiate out from exposed Cu-Pb-Zn veins, from an outcrop of molybdenite stockwork veins and from associated iron-stained altered rock. Te haloes intensify exponentially with proximity to known ore and suggest the presence of Summitville-type chimney deposits. Most of the gold- and silver-telluride ore in the Cripple Creek district, Colorado, is found in fracture fillings within a volcanic subsidence basin. Haloes of Au, Ag and Te all define tne mineralized portions of the fissure veins.
Strychnine-sensitive glycine receptors on pyramidal neurons in layers II/III of the mouse prefrontal cortex are tonically activated

Processing of signals within the cerebral cortex requires integration of synaptic inputs and a coordination between excitatory and inhibitory neurotransmission. In addition to the classic form of s...
Contagion in a Crowd: Conditions under Which a Crowd Will Reverse Itself

(1978). Contagion in a Crowd: Conditions under Which a Crowd Will Reverse Itself. The Journal of Social Psychology: Vol. 105, No. 2, pp. 313-314.
Inactivation of Glutathione Peroxidase by Benzaldehyde

Chronic benzaldehyde exposure is known to cause central nervous system (CNS) disturbances. Previous studies have shown that benzaldehyde causes the formation of reactive oxygen species (ROS) in rat synaptosomal fractions. Benzaldehyde has also been implicated in ROS formation in the CNS of rats treated with toluene. We have found that benzaldehyde effectively inactivates the antioxidant enzyme glutathione peroxidase (Ki approximately 15 microM), but has no effect on the other antioxidant enzymes tested: catalase, superoxide dismutase, and glutathione reductase. This effect has been found to be specific to benzaldehyde since other structurally related and unrelated aldehydes tested were found to be devoid of inactivating capacity toward glutathione peroxidase. Since glutathione peroxidase is the main enzyme responsible for removal of hydrogen peroxide and organic hydroperoxides in brain, its inactivation by benzaldehyde may be a main contributor to the observed ROS formation and the observed neurotoxicity caused by either benzaldehyde or toluene exposure.
A Resident's View of Medical Ethics

Excerpt To the Editors:In my experience as a resident, medical ethics is underemphasized in physician training. Once clinical training begins, there is essentially no guidance in dealing with ethic...
Regional processes in mangrove ecosystems : spatial scaling relationships, biomass, and turnover rates following catastrophic disturbance

Physiological processes and local-scale structural dynamics of mangroves are relatively well studied. Regional-scale processes, however, are not as well understood. Here we provide long-term data on trends in structure and forest turnover at a large scale, following hurricane damage in mangrove ecosystems of South Florida, U.S.A. Twelve mangrove vegetation plots were monitored at periodic intervals, between October 1992 and March 2005. Mangrove forests of this region are defined by a −1.5 scaling relationship between mean stem diameter and stem density, mirroring self-thinning theory for mono-specific stands. This relationship is reflected in tree size frequency scaling exponents which, through time, have exhibited trends toward a community average that is indicative of full spatial resource utilization. These trends, together with an asymptotic standing biomass accumulation, indicate that coastal mangrove ecosystems do adhere to size-structured organizing principles as described for upland tree communities. Regenerative dynamics are different between areas inside and outside of the primary wind-path of Hurricane Andrew which occurred in 1992. Forest dynamic turnover rates, however, are steady through time. This suggests that ecological, more-so than structural factors, control forest productivity. In agreement, the relative mean rate of biomass growth exhibits an inverse relationship with the seasonal range of porewater salinities. The ecosystem average in forest scaling relationships may provide a useful investigative tool of mangrove community biomass relationships, as well as offer a robust indicator of general ecosystem health for use in mangrove forest ecosystem management and restoration.
Further studies on the hrr field of a moving crack, an experimental analysis

Abstract An improved moire interferometry was used to record simultaneously both the vertical and horizontal displacements associated with stable crack growth in uniaxially loaded 5052H32 aluminum, single-edge-notched specimens. For stable crack growth up to 2 mm, the vertical displacement field showed the dominance of the HRR field. The HRR field was detected in the horizontal displacement only at the initial stage of loading. The far and near field J- integrals were path independent during this incremental crack extension period. These and previous results involving 2024-0 and 2024-T3 aluminum specimens indicate that J- characterization of a crack is not valid for these ductile materials in this specimen configuration.