cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnetic anisotropy in epitaxial CrO2 and CrO2/Cr2O3 bilayer thin films

We have investigated the effective magnetic anisotropy in CVD-grown epitaxial $\mathrm{Cr}{\mathrm{O}}_{2}$ thin films and ${\mathrm{Cr}}_{2}{\mathrm{O}}_{3}∕\mathrm{Cr}{\mathrm{O}}_{2}$ bilayers using resonant radio-frequency transverse susceptibility (TS). While $\mathrm{Cr}{\mathrm{O}}_{2}$ is a highly spin polarized ferromagnet, ${\mathrm{Cr}}_{2}{\mathrm{O}}_{3}$ is known to exhibit magnetoelectric effect and orders antiferromagnetically just above room temperature. In $\mathrm{Cr}{\mathrm{O}}_{2}$, the measured values for the room temperature anisotropy constant scaled with the film thickness and the TS data is influenced by magnetoelastic contributions at low temperature due to interfacial strain caused by lattice mismatch with the substrate. In $\mathrm{Cr}{\mathrm{O}}_{2}∕{\mathrm{Cr}}_{2}{\mathrm{O}}_{3}$ bilayers $M\text{\ensuremath{-}}H$ loops indicated an enhanced coercivity without appreciable loop shift and the transverse susceptibility revealed features associated with both the ferromagnetic and antiferromagnetic phases. In addition, a considerable broadening of the anisotropy fields and large ${K}_{\mathrm{eff}}$ values were observed depending on the fraction of ${\mathrm{Cr}}_{2}{\mathrm{O}}_{3}$ present. This anomalous behavior, observed for the first time, cannot be accounted for by the variable thickness of $\mathrm{Cr}{\mathrm{O}}_{2}$ alone and is indicative of possible exchange coupling between $\mathrm{Cr}{\mathrm{O}}_{2}$ and ${\mathrm{Cr}}_{2}{\mathrm{O}}_{3}$ phases that significantly affects the effective magnetic anisotropy.
Instrumenting the world with wireless sensor networks

Pervasive micro-sensing and actuation may revolutionize the way in which we understand and manage complex physical systems: from airplane wings to complex ecosystems. The capabilities for detailed physical monitoring and manipulation offer enormous opportunities for almost every scientific discipline, and it will alter the feasible granularity of engineering. We identify opportunities and challenges for distributed signal processing in networks of these sensing elements and investigate some of the architectural challenges posed by systems that are massively distributed, physically-coupled, wirelessly networked, and energy limited.
Nonuniform sampling/oversampling and extensions for wavelet subspaces

In this paper, we generalize existing sampling theory for wavelet subspaces, in several directions. These new schemes allow for compactly supported synthesizing and scaling functions, which was not possible before. All the problems are treated in a unified way using multirate filter banks. This offers simple and efficient implementations of the algorithms. This new possibility of having compactly supported synthesizing functions is used for very efficient computation of inner products in multiresolution subspaces. >
Correlation between OH concentration and oxygen isotope diffusion rate in diopsides from the Adirondack Mountains, New York

The concentration of structural OH in diopside was determined for four granulite facies siliceous marble samples from the Adirondack Mountains, New York, using FTIR spectroscopy. Single-crystal polarized IR spectra were measured on (100) and (010) sections of diopside. The relative intensities of four OH bands in the 3700–3200 cm^(–1) region vary among the samples, with the 3645 cm^(–1) band dominating the spectra of diopside from a xenolith at Cascade Slide. Total OH content in the diopsides ranges from 55 to 138 ppm H_(2)O by weight. The OH concentration in diopside increases monotonically with increasing f_H2O for the sample, as estimated using oxygen isotope systematics for diffusion rates in these samples from Edwards and Valley (1998). There is no significant variation in OH content within a single diopside grain or among diopside grains from the same hand sample. Charge-coupled substitution with M^3+ and Ti^4+ in the crystal structure may have allowed retention of OH in the diopside structure during and after peak metamorphism (~750 °C, 7–8 kbar). The Cascade Slide diopsides have an Fe^3+/Fe^2+ of 0.98, compared to Fe^3+/Fe^2+ (0 to 0.05) for the other samples, implying that some loss of hydrogen through oxidation of Fe was possible in this sample. This is the first study we know of which shows that the OH content in anhydrous minerals from natural samples correlates to the rate of oxygen isotope diffusion.
Postprandial triglyceride and retinyl ester responses to oral fat: effects of fructose

It has been shown that addition of fructose to an oral fat load results in higher postprandial concentrations of triglyceride. The present study, performed in 11 healthy volunteers, was initiated to see whether the effect of fructose on fat-induced lipemia also involved changes in postprandial concentrations of triglyceride-rich lipoproteins of intestinal origin. Vitamin A was used to label intestinal lipoproteins, and the retinyl palmitate concentrations were determined in plasma and in the Sf > 400 and Sf 20-400 lipoprotein fractions (Sf denotes the Svedberg flotation index). Addition of fructose (50 g) to a standard (40-g oral) fat load resulted in higher postprandial concentrations of triglyceride and retinyl palmitate in plasma and the Sf > 400 lipoprotein fraction (P < 0.001, analysis of variance), and the higher the fasting plasma triglyceride concentration, the greater the magnitude of the fructose effect (r = 0.83, P < 0.002). These data show that triglyceride-rich lipoproteins of intestinal origin play a role in the fructose-induced accentuation of postprandial lipemia.
Mobile UNITY: reasoning and specification in mobile computing

Mobile computing represents a major point of departure from the traditional distributed-computing paradigm. The potentially very large number of independent computing units, a decoupled computing style, frequent disconnections, continuous position changes, and the location-dependent nature of the behavior and communication patterns present designers with unprecedented challenges in the areas of modularity and dependability. So far, the literature on mobile computing is dominated by concerns having to de with the development of protocols and services. This article complements this perspective by considering the nature of the underlying formal models that will enable us to specify and reason about such computations. The basic research goal is to characterize fundamental issues facing mobile computing. We want to achieve this in a manner analogous to the way concepts such as shared variables and message passing help us understand distributed computing. The pragmatic objective is to develop techniques that facilitate the verification and design of dependable mobile systems. Toward this goal we employ the methods of UNITY. To focus on what is essential, we center our study on ad hoc networks, whose singular nature is bound to reveal the ultimate impact of movement on the way one computes and communicates in a mobile environment. To understand interactions we start with the UNITY concepts of union and superposition and consider direct generalizations to transient interactions. The motivation behind the transient nature of the interactions comes from the fact that components can communicate with each other only when they are within a a certain range. The notation we employ is a highly modular extension of the UNITY programming notation. Reasoning about mobile computations relies on extensions to the UNITY proof logic.
Circadian rhythms and circadian rhythm disorders in children and adolescents

A clinically applicable review of circadian rhythm physiology is presented, including a detailed examination of the interaction of circadian and homeostatic systems and the maturation of the circadian system from preconception through adolescence. Emphasis is placed on the clinical evaluation gathering information through the history, sleep log, and if necessary, actigraphy and polysomnography. Circadian disorders, including advanced sleep phase syndrome, circadian disorders seen in blind children, delayed sleep phase syndrome, and non-24-hour sleep phase are described. Case descriptions of each are provided. Treatment and interventions for these disorders are described, including the importance of education, light therapy, sleep-wake schedule adjustments, and the occasional use of medications, such as sedative hypnotics and melatonin.
Locking the kink in the influenza hemagglutinin fusion domain structure.

We have previously identified Trp14 as a critical residue that stabilizes the kink in the boomerang structure of the influenza fusion domain and found that cells expressing hemagglutinin with a Trp14 to Ala mutation cannot fuse with red blood cells. However, mutating another aromatic residue, Phe9, on the other side of the kink did not have a significant effect on fusion or the ability of the mutant fusion peptide to bind to or perturb the bilayer structure of lipid model membranes. We reasoned that Phe is not as potent to contribute to the kink as the larger Trp and that the cooperation of Phe9 and Ile10 might be needed to elicit the same effect. Indeed, the double mutant F9A/I10A diminished cell-cell fusion and the ability of the fusion domain to bind to and perturb lipid bilayers in a similar fashion as the W14A mutant. A structure determination of F9A in lipid micelles by solution NMR shows that F9A adopts a similarly kinked structure as wild type. Distances between the two arms of the boomerang structure of wild type, F9A, W14A, and F9A/I10A in lipid bilayers were measured by double electron-electron resonance spectroscopy and showed that the kinks of W14A and F9A/I10A are more flexible than those of wild type and F9A. These results underscore the importance of large hydrophobic residues on both sides of the kink region of the influenza hemagglutinin fusion domain to fix the angle of the boomerang structure and thereby confer fusion function to this critical domain.
Lead and Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms: A meta-analysis

Abstract This meta-analysis examined the association between Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms and lead exposure in children and adolescents. Thirty-three studies published between 1972 and 2010 involving 10,232 children and adolescents were included. There was a small to medium association between inattention symptoms and lead exposure (r = .16, k = 27, p
The Influence of High Air Temperatures: No. 1.

The aim of the following investigations was to ascertain the limits within which men can continue to exist normally, and to work, when the air temperature is abnormally high: also to study the abnormal phenomena which are produced when these limits are exceeded.
Evaluation of sugarcane evapotranspiration from water table data in the everglades agricultural area

Abstract The limited fresh water supply in south Florida has emerged as a major point of contention between the urban, environmental, and agricultural sectors. The mandated water quality improvement measures suggest the retention of water on farms (up to 20% of historical drainage pumping) could further impact the regional water supply. Accurate measures of evapotranspiration (ET) are vital in order to prudently plan for the equitable distribution of water. The daily changes in field water table depths were used to evaluate the actual evapotranspiration for sugarcane grown in the Histosols of the Everglades Agricultural Area (EAA) in south Florida. Water table recorders were installed in eight independently irrigated and drained plots, each 0.55 ha. Water table monitoring was conducted for a period of two years, 1990 and 1991, and the results were the average of these two years. The crop was plant and first ratoon. Each month, periods of time when no rainfall, irrigation, or drainage occurred were selected for use in ET determination. The time periods ranged from 5 to 19 days. Assuming that there were no seepage or deep percolation the daily declines in water tables, which exhibited clear diurnal patterns, were then used to determine the change in soil water losses during the selected time periods, the change in soil water storage was representative of actual sugarcane ET. Pan evaporation and crop growth were also monitored. The amount of water released from the soil during drainage was determined in laboratory columns. Five transparent PVC pipes, 12.1 cm in diameter were used to remove undisturbed 110 cm deep cores from the field. The columns of soil were saturated and drained to determine the drainable porosity of the soil. The water table data exhibited diurnal trends, with declines close to zero at midnight and maximum declines occurring between 2:00 and 3:00 pm. The data showed that minimum ET rates occurred during December through February (0.7–1.5 mm dayt−1 ). Maximum ET rates (4.5–4.6 mm dayt−1 ) occurred during June through September. Total ET was 106.2 cm per year. Using the actual field measured ET, crop coefficients (Kc) were calculated for sugarcane for the Penman, Thornthwaite, and Blaney-Criddle methods of determining potential evapotranspiration (ETp).
No Greater Sacrifice: American Airlines Employee Crisis Response to the September 11 Attack

This case study reports the identification strategies and related tactics that American Airlines CEO Don Carty and his team of professional communicators used in their employee crisis response to the September 11 attack. Data analyzed in the study include 78 internal documents; 10 articles from the airline's corporate newspaper; and interviews with Timothy Doke, then American Airlines Vice President of Corporate Communications, and Andrea Rader, a senior member of Doke's team. The results of this study provide guidance to corporate communicators tasked with rebuilding employee morale after a malevolent-type crisis.
FEX: A Knowledge-Based System For Planimetric Feature Extraction

Topographical planimetric features include natural surfaces (rivers, lakes) and man-made surfaces (roads, railways, bridges). In conventional planimetric feature extraction, a photointerpreter manually interprets and extracts features from imagery on a stereoplotter. Visual planimetric feature extraction is a very labour intensive operation. The advantages of automating feature extraction include: time and labour savings; accuracy improvements; and planimetric data consistency. FEX (Feature EXtraction) combines techniques from image processing, remote sensing and artificial intelligence for automatic feature extraction. The feature extraction process co-ordinates the information and knowledge in a hierarchical data structure. The system simulates the reasoning of a photointerpreter in determining the planimetric features. Present efforts have concentrated on the extraction of road-like features in SPOT imagery. Keywords: Remote Sensing, Artificial Intelligence (AI), SPOT, image understanding, knowledge base, apars.
The importance of surface diffusion for crystal growth from solution

Abstract Upon exploring the implications of the existing model for crystal growth from solutions, it is shown that surface diffusion plays an essential role in the growth process and that the observed shapes of spirals and habits of crystals described in terms of the morphological theory of Hartman and Perdok can be explained on the basis of the surface diffusion model of Burton, Cabrera and Frank. It will be shown that the shape of the rate of growth versus relative supersaturation curves of ethylene diamine tartrate, measured by Booth and Buckley, can be explained on this basis.
The changing of the guard: a case study of change in computing

Change, in the context of computing environments, can assume a number of forms, varying widely in nature and degree. At Tulane University, Tulane Computing Services initiated a significant change in the Office of the President of the University: the existing system of stand-alone MS-DOS microcomputers was replaced by a Macintosh local area network complete with laser printing, mainframe communications, and shared file access. In this instance, the director of the department (the President of the University) directed that the change take place, and the central computing organization and the President's office staff worked together to accomplish the transition to the new computing environment. The change was effected with minimal disruption to the department's operations.This paper describes the successful implementation of change from one computing environment to another. We discuss the planning and preparation involved in facilitating change, the training and education required for those involved in the change, and the attitudes of the individuals affected by the change. An important component of the process was interviews conducted with those involved. These interviews were conducted in order to determine the factors which influence an individual's attitudes toward change, specifically in the context of computing environments.
Cardenas receives, 2011 Early Career Hydrologic Sciences Award: Citation

Meinhard Bayani Cardenas received the 2011 Early Career Hydrologic Sciences Award at the 2011 AGU Fall Meeting, held 5–9 December in San Francisco, Calif. The award is for significant early career contributions to hydrologic science.
Economic production cycles and setup reduction in an imperfect production system

Abstract This paper considers an economic production quantity model with imperfect production processes where the setup cost is function of capital expenditure. The mathematical model is derived to determine the optimal production run length and investment in setup cost reduction such that the total cost per unit time is minimized. In addition, an efficient algorithm is provided to find the optimal production run length and setup cost. A numerical example is provided to illustrate the results and to assess the cost savings realized by adopting investment strategy. Furthermore, some managerial implications are also included.
Residual-Based Tests for Normality in Autoregressions: Asymptotic Theory and Simulation Evidence

Existing results for the asymptotic validity of the Jarque–Bera test in vector autoregressive (VAR) models assume stationarity. In applied work, however, researchers often work with possibly integrated and cointegrated process. We prove the asymptotic validity of the Jarque–Bera test for vector error-correction (VEC) models and for unrestricted VAR models with possibly integrated or cointegrated variables. We also propose the use of bootstrap critical values in stationary VAR models and in VEC models. We show that the bootstrap version of the Jarque–Bera test is considerably more accurate in small samples than the asymptotic test, even for processes with roots close to unity.
Use of micrococcal nuclease to monitor hybridization reactions with DNA.

Abstract Assay conditions are described whereby commercially available micrococcal nuclease selectively degrades single-stranded DNA while leaving DNA:DNA and DNA:RNA hybrids intact. Use of the enzyme to monitor hybridization reactions involving DNA is discussed.
Uptake and subcellular cleavage of organomercury compounds by rat liver and kidney

Abstract The uptake and transformation of phenylmercuric acetate (PMA), ethylmercury chloride (EMC), and methylmercury chloride (MMC) by rat liver, kidney, and brain slices were investigated. A slightly greater enzymatic activity for the cleavage of PMA and EMC was observed in the kidney than in the liver; brain tissue had the least activity. The average rates of C-Hg cleavage were 2.4 to 3.0 nmole g−1 h−1 for PMA and 0.9 to 1.0 nmole g−1 h−1 for EMC. No cleavage of C-Hg bond from MMC was observed by the kidney and liver. The cleavage of PMA was an enzymatic process and the enzyme was located in the nuclear fraction of both liver and kidney. The apparent Michaelis constant and the maximal velocity value for PMA conversion by rat liver slices were 625 μM and 19.2 nmole per g tissue per 2 h, respectively. It is postulated that the PMA molecule is first split at the C-Hg bond to yield benzene and mercuric ion. The cleavage of the EMC molecule appears to be more complex.
Assessing knowledge of cardiovascular health-related diet and exercise behaviors in Anglo- and Mexican-Americans.

Abstract This article describes the Adult and Child Behavior Knowledge Scales that were used as part of the San Diego Family Health Project to measure knowledge of health behaviors related to cardiovascular diseases in two ethnic groups: Anglo- and Mexican-Americans. The psychometric characteristics of these scales indicate acceptable reliabilities for assessing knowledge of dietary sodium, dietary fat, and exercise among both adults and children and differ from other health knowledge scales in that they focus on “behavioral capability” rather than on the link between behavior and disease. It is believed that the type of information measured by our scales is more closely related to behavior changes sought in contemporary cardiovascular disease prevention trials. Results of ANOVA used to test differences in knowledge by ethnicity and sex indicate strong main effects for ethnicity among both children and adults. However, sex was not consistently related to knowledge, except for the general tendency of males to be more knowledgeable about exercise. Step-wise and simultaneous-entry multiple regression were used to test a subset of variables, including sex, education, self-efficacy, acculturation (for Mexican-Americans), and parental health knowledge (for children) as determinants of health knowledge. Education was the strongest predictor for Anglo-American adults, and acculturation level was the strongest for Mexican-American adults. Among children, the only statistically significant variable was parental acculturation level for Mexican-Americans. The scales were found to be useful in measuring differences in knowledge across cultural/linguistic groups and to clearly identify marginally acculturated Mexican-Americans as being least aware of health-behavior knowledge. Implications are discussed.
Permanent series of prolonged pseudopregnancy periods in panhysterectomized rats

Abstract Use of the spontaneous running activity method showed that in domesticated rats panhysterectomy (removal of the entire reproductive tract — vagina, uterus and tubes) — resulted in permanent series of prolonged (18–22 days) pseudopregnancy periods. After panhysterectomy the rats were normally active showing regular 4 or 5 day estrous cycles for 78–160 days before appearance of the first pseudopregnancy period. Periods of activity between pseudopregnancy periods showed regular 4 or 5 day estrous cycles and became shorter with time while lengths of pseudopregnancy periods remained the same. Panhysterectomized trapped wild Norway rats that are better equipped to withstand stress did not show the pseudopregnancy periods. Excessive secretion of cortisone or estrogen or of both in absence of the reproductive tract might account for lengthening of the life of the corporal lutea. The periods themselves could result from stress produced by loss of the reproductive tract. Pseudopregnancy periods do not depend on stimulation from the tip of the cervix.
Advances in Behavioral Science Using Automated Facial Image Analysis and Synthesis [Social Sciences]

The face conveys information about a person's age, sex, background, and identity; what they are feeling, thinking, or likely to do next. Facial expression regulates face-to-face interactions, indicates reciprocity and interpersonal attraction or repulsion, and enables intersubjectivity between members of different cultures. Facial expression indexes neurological and psychiatric functioning and reveals personality and socioemotional development. Not surprisingly, the face has been of keen interest to behavioral scientists. About 15 years ago, computer scientists became increasingly interested in the use of computer vision and graphics to automatically analyze and synthesize facial expression. This effort was made possible in part by the development in psychology of detailed coding systems for describing facial actions and their relation to basic emotions, that is, emotions that are interpreted similarly in diverse cultures. The most detailed of these systems, the Facial Action Coding System (FACS), informed the development of the MPEG-4 facial animation parameters for video transmission and enabled progress toward automated measurement and synthesis of facial actions for research in affective computing, social signal processing, and behavioral science. This article reports key advances in behavioral science that are becoming possible through these developments. Before beginning, automated facial image analysis and synthesis (AFAS) is briefly described.
BASIC FUCHSIN-CRYSTAL VIOLET; A RAPID STAINING SEQUENCE FOR JUXTAGLOMERULAR GRANULAR CELLS EMBEDDED IN EPOXY RESIN.

A basic fuchsin-crystal violet staining sequence for demonstration of juxtaglomerular granular cells in epoxy-embedded tissues is rapid and results in slides with excellent contrast and intensity. Procedure: Cut sections 0.3-0.6 μ thick. Hydrate through xylene and alcohol to water. Stain in modified Goodpasture's stain (basic fuchsin, 1; aniline, 1; phenol, 1; 30% alcohol, 100) for 20-30 sec; rinse in tap water; stain in modified Stirling's (crystal violet, 5; alcohol, 10; aniline, 2; water, 88) for 20-30 sec; rinse in tap water and dry on a hotplate; mount in a synthetic resin. Granular cells of the juxtaglomerular apparatus are stained an intense dark blue by the crystal violet. Arterial elastic membranes and collagen are pale blue. Other structures are shades of red.
Regulatory role of Glu546 in flavin mononucleotide-heme electron transfer in human inducible nitric oxide synthase.

Nitric oxide (NO) production by mammalian NO synthase (NOS) is believed to be regulated by the docking of the FMN domain in one subunit of the dimer onto the heme domain of the adjacent subunit. Glu546, a conserved charged surface residue of the FMN domain in human inducible NOS (iNOS), is proposed to participate in the interdomain FMN/heme interactions [Sempombe et al. Inorg. Chem. 2011, 50, 6869–6861]. In the present work, we further investigated the role of the E546 residue in the FMN–heme interdomain electron transfer (IET), a catalytically essential step in the NOS enzymes. Laser flash photolysis was employed to directly measure the FMN–heme IET kinetics for the E546N mutant of human iNOS oxygenase/FMN (oxyFMN) construct. The temperature dependence of the IET kinetics was also measured over the temperature range of 283 – 304 K to determine changes in the IET activation parameters. The E546N mutation was found to retard the IET by significantly raising the activation entropic barrier. Moreover, pulsed electron paramagnetic resonance data showed that the geometry of the docked FMN/heme complex in the mutant is basically the same as in the wild type construct, whereas the probability of formation of such a complex is about twice lower. These results indicate that the retarded IET in the E546N mutant is not caused by an altered conformation of the docked FMN/heme complex, but by a lower population of the IET-active conformation. In addition, the negative activation entropy of the mutant is substantially lower than that of the holoenzyme. This supports a mechanism by which the FMN domain can modify the IET, through altering probability of the docked state formation.
Changes in RNA and protein synthesis in the neural retina during lens regeneration in newts

Since neural retina stimulates regeneration of a lens from the dorsal iris in newts, RNA and protein synthesis in the neural retina was investigated during this process. Incorporation of 3H-uridine and 3H-leucine using liquid scintillation counting was employed to compare RNA and protein synthesis in the neural retina from sham-operated control eyes with that in eyes during lens regeneration. An initial increase in 3H-uridine uptake was seen one to three days after lentectomy. This was followed by greater incorporation of 3H-leucine, indicating increased protein synthesis between 5 to 15 days after lens removal. A decrease in 3H-uridine uptake was also seen at 5 to 12 days after lentectomy. After 20 days both the RNA and protein synthesis returned to the normal level. Since the increase in protein synthesis is preceded by an increase in RNA synthesis, the two processes might be related. The results indicate significant changes in the synthesis of macromolecules by the neural retina following lentectomy. These may be indirectly related to the production of the neural retinal factor with stimulates lens differentiation.
Partial angle inversion recovery (PAIR) MR imaging: spin-echo and snapshot implementation.

The effects of varying the inversion or excitation RF pulse flip angles on image contrast and imaging time have been investigated in IR imaging theoretically, with phantoms and with normal volunteers. Signal intensity in an IR pulse sequence as a function of excitation, inversion and refocusing pulse flip angles was calculated from the solution to the Bloch equations and was utilized to determine the contrast behavior of a lesion/liver model. Theoretical and experimental results were consistent with each other. With the TI chosen to suppress the fat signal, optimization of the excitation pulse flip angle results in an increase in lesion/liver contrast or allows reduction in imaging time which, in turn, can be traded for an increased number of averages. This, in normal volunteers, improved spleen/liver contrast-to-noise ratio (9.0 vs. 5.7, n = 8, p < 0.01) and suppressed respiratory ghosts by 33% (p < 0.01). Reducing or increasing the inversion pulse from 180° results in shorter TI needed to null the signal from the tissue of interest. Although this decreases the contrast-to-noise ratio, it can substantially increase the number of sections which can be imaged per given TR in conventional IR imaging or during breathhold in the snapshot IR (turboFLASH) technique. Thus, the optimization of RF pulses is useful in obtaining faster IR images, increasing the contrast and/or increasing the number of imaging planes.
Evidence from human scalp electroencephalograms of global chaotic itinerancy

My objective of this study was to find evidence of chaotic itinerancy in human brains by means of noninvasive recording of the electroencephalogram (EEG) from the scalp of normal subjects. My premise was that chaotic itinerancy occurs in sequences of cortical states marked by state transitions that appear as temporal discontinuities in neural activity patterns. I based my study on unprecedented advances in spatial and temporal resolution of the phase of oscillations in scalp EEG. The spatial resolution was enhanced by use of a high-density curvilinear array of 64 electrodes, 189 mm in length, with 3 mm spacing. The temporal resolution was advanced to the limit provided by the digitizing step, here 5 ms, by use of the Hilbert transform. The numerical derivative of the analytic phase revealed plateaus in phase that lasted on the order of 0.1 s and repeated at rates in the theta (3–7 Hz) or alpha (7–12 Hz) ranges. The plateaus were bracketed by sudden jumps in phase that usually took place within 1 to 2 digitizing steps. The jumps were commonly synchronized in each cerebral hemisphere over distances of up to 189 mm, irrespective of the orientation of the array. The jumps were usually not synchronized across the midline separating the hemisphere or across the sulcus between the frontal and parietal lobes. I believe that the widespread synchrony of the jumps in analytic phase manifest a metastable cortical state in accord with the theory of self-organized criticality. The jumps appear to be subcritical bifurcations. They reflect the aperiodic evolution of brain states through sequences of attractors that on access support the experience of remembering.
Temperature-Modulated Reflectance of Gold from 6 to 35 eV

the measured cross section and critical temperatures of the microbridges end the bulk critical fields are 10' to 10' times greater than the measured current-biased values. Therefore, the overall agreement between the experiment and the AL-MH theory is quite encouraging as the experiment was done at microwave frequencies while the theory was derived assuming a dc current flowing through the microbridge. In summary the creation and collapse of localized dissipative centers in tin microbridges has been used to monitor the thermally activated motion of magnetic flux into and out of the superconducting ring. The observed switching rates are in good agreement with the theory of McCumber and Halperin. The rates were found to follow an exponential dependence in the lower-temperature region, and then with increasing temperatures the rate was found to peak and finally decrease as the temperature approached the transition temperature of the film. This is the first experimental observation of the peaking predicted by the model of McCumber and Halperin. The numerical values deduced for the free-energy barrier and the transition rate scale with microbridge cross-sectional area and are in reasonable agreement with the values prediced by McCumber and Halperin. We would like to thank Professor M. Tinkham for sending us several preprints and Professor Beasley and Dr. W. J. Skocpol for stimulating discussions of their work. We would also like to thank Professor H. Fink for his preprints and helpful discussions.
F 3 + Center in NaF

Stress splitting and polarization of the 5456-\AA{} zero-phonon line in irradiated NaF suggest that this line and its mirror absorption and emission bands are due to the predicted $^{1}A_{1}\ensuremath{\leftrightarrow}^{1}E$ transition of the ${{F}_{3}}^{+}$ center.
Articulatory preparation in the delayed naming task

The assumptions that acoustic onset must follow articulatory onset by a fixed delay and that response execution level processes are always effectively isolated in the delayed naming task were investigated with respect to the issue of articulatory preparation in three experiments. The results of these experiments showed that for the delayed naming task with the standard instructions (1) there was differential preparation across the different delays, with articulatory preparation being initiated earlier relative to the signal to respond in the longer delays (in some cases, even before the signal to respond was given); (2) the articulatory onset to acoustic onset interval (AAI) was variable across the different delays as a direct consequence of differential preparation; and (3) preparation included the building up of pressure for word-initial plosives when it was possible. However, when explicit instructions were given to minimize articulatory preparation in advance, an acoustic latency difference between plosives and nasals was found even with long delays. Moreover, comparison of the delayed naming task under different instructions and the standard naming task showed that execution of a response, in terms of acoustic latency and segment duration, can vary systematically across instructions and tasks. Methodological and theoretical implications of these results are discussed.
Computer Simulation of Marine Sedimentation: ABSTRACT

Geology has lacked an effective experimental approach to many problems. Although some kinds of experiments can be carried out, such as sediment transport on a stream table, most geologic processes cannot be re-created in the laboratory. A mountain range can be observed in the field, but neither the mountain range nor the mountain-building processes can be duplicated in the laboratory. These are shortcomings of which geologists are fully aware. There is, however, another shortcoming in the geologist's kit of tools--namely, his difficulty in dealing with many interdependent variables or processes that mutually and simultaneously affect each other. However, computers can be used, in conjunction with appropriate mathematical geologic models, to perform kinds of experiments which otherwise could be performed only with difficulty, or not at all. Furthermore, these computer models are ideally suited for "exploring" the effects of interdependent geologic processes that are linked together to form dynamic systems. The processes of marine sedimentation are highly interdependent. All too commonly, geologists who study stratigraphic sequences attempt to interpret the depositional environments of the strata in terms of only one or two variables--such as water depth or wave energy. Clearly, methods of analyzing the effects of multiple interdependent geologic variables are needed. Computerized, dynamic mathematical models which represent geologic processes and products in two- or three-dimensional space provide one method of attack. These models are philosophically identical to dynamic oil-reservoir simulation models, and they also share many of their constructional details. Most dynamic geologic simulation models can be constructed from relatively few mathematical "building blocks," which may be grouped into the following categories: (1) materials-balance accounting systems; (2) sources of random variables; (3) Markov chains; (4) flow and transport mechanisms using finite-difference methods of representing diffusion and fluid-flow processes; (5) feedback control; (6) optimization; and (7) graphic display. Virtually all models employ methods in which both space and time are compartmented into small increments. Experiments with relatively simple sedimentation models suggest that feed-back control exerts much influence on sedimentary sequences. A lag in the isostatic adjustment of the crust in response to the load imposed by deposition of sediment may be responsible for some of the large-scale rhythms in cyclic sedimentation. Simulation models can be used effectively to explore the results of different assumed lag factors in sedimentation/isostatic-adjustment feedback loops. End_of_Article - Last_Page 555------------
Structure and Possible Function of an α-Tocopherol-Binding Protein

A protein has been isolated from rat liver cytosol that specifically binds α-tocopherol. It does not occur in other tissues. Its amino acid sequence has been determined and it was found to have great homology with 11 -cis-retinaldehyde-binding protein of the retina. This tocopherol-binding protein may be defective in a certain type of familial vitamin E deficiency syndrome.
A Drosophila gene with predicted rhoGEF, pleckstrin homology and SH3 domains is highly expressed in morphogenic tissues.

Abstract We have identified a Drosophila gene that has substantial sequence homology to a distinct class of proto-oncogenes that includes DBL, VAV, Tiam-1, ost and ect-2. It has predicted Rho or Rac guanine exchange factor (Rho/RacGEF) and pleckstin homology (PH) domains with the PH immediately downstream of the Rho/RacGEF. Rho/RacGEFs catalyze the dissociation of GDP from the Rho/Rac subfamily of Ras-like GTPases, thus activating the target Rho/Rac ( Takai et al. (1995) Trends Biochem. Sci. 20, 227–231]. Members of the Rho/Rac subfamily regulate organization of the actin cytoskeleton, which controls the morphology, adhesion and motility of cells ( Nobes et al. (1995) J. Cell Sci. 108, 225–233; Ridley and Hall (1992) Cell 70, 389–399; Ridley et al. (1992) Cell 70, 401–410]. Message from this gene is found throughout oogenesis and embryogenesis. Of particular interest, message is most abundant in furrows and folds of the embryo where cell shapes are changing and the cytoskeleton is likely to be undergoing reorganization.
Transaction costs and trading behavior in an immature water market

Water scarcity is a constraint on economic activity in many regions, and improving the allocation of water is an important part of the process of economic development. Economists have advocated water markets as a way to increase efficiency and to cope with environmental problems. Unfortunately, actual water markets, including those in developed countries, usually fall far short of this ideal. The paper considers the allocation of water by markets that are only imperfectly developed, in which prices are not publicly known and in which there is no centralized trading location. These limitations impose transaction costs on buyers and sellers, that is costs associated with completing a transaction. A conceptual model of the effect of transaction costs on trading patterns is developed. Stylized results are tested using data from an informal water market in California. The paper concludes with a description of the importance of transaction costs, comments on the transition to more formal water markets, and policy recommendations.
Integrating Pharmacokinetics into Point-of-Care Information Systems

Computer-based patient care information systems (PCIS) have emerged as an integral component of healthcare organisations. Currently, 4 models of PCIS exist: the centralised model, the hub-and-spoke model, the network model, and the distributed model.
Theoretical description of the anomalous q-dependence of the zero degree binary peak in Fq+ + H2 collisions

Abstract The anomalous q -dependence of the zero degree binary peak recently observed by Richard et al. [J. Phys. B23 (1990) L213] is explained in terms of the differences between the scattering of target electrons by either a bare or a clothed projectile. Calculations have been performed using the impulse or binary encounter approximation. That is, the convolution of the quantum mechanical elastic cross section and the target momentum distribution is calculated. The non-Coulomb phase-shifts due to the screened projectile-electron interaction were obtained by direct integration of the radial Schrodinger equation using Hartree-Fock model potentials. Very good agreement is obtained between theory and experiment and, furthermore, this model is used to illuminate the underlying dynamics which leads to the anomalous behavior.
Voting for 'Sin' in Kansas

One of the issues raised in the economics literature on legislative voting is the role played by legislator ideology. Holding constituent interests constant, a finding of ideological impact is taken as evidence of shirking in a political principal-agent model. A problem in implementing such studies is how to measure both constituent interests and legislator ideology. Earlier studies have used a vector of socio-economic variables characterizing a legislator's district for the former. The latter has been measured by group ratings of liberal or conservative Congressional watchdogs, such as Americans for Democratic Action, and other indices based on voting records.1 Studies by Kalt (1980) and Peltzman (1984) have strongly suggested that what was masquerading as legislator ideology is actually, to a large degree, a measure of constituent interests. This was demonstrated by regressing group ratings on constituent variables. When Kalt and Zupan (1984), however, decomposed an ideology index into a constituent component and a legislator residual, they found that both had explanatory power in explaining United States Senate voting on anti-strip mine legislation. But it is not clear whether the legislative residual measured a Senator's ideology or was simply correlated with omitted constituent variables. Recent events in Kansas provide an opportunity to shed new light on the debate. In the November 1986 elections, Kansans voted on constitutional amendments, permitting liquor-by-the-drink, pari-mutuel wagering and a state-run lottery. Collectively, they came to be known as the 'Sin' issues, although they were generally supported on economic grounds. The amendments had earlier been approved by the Kansas legislature in separate roll call votes. Using con-
Utility perturbations and the equilibrium price set

Abstract For pure exchange economies in which agents are described by a compact smooth manifold of smooth strictly monotonic and strictly concave utilities, it is shown that, at least generically, the equilibrium price set is a smooth manifold of the same dimension. Given any smooth selection from the equilibrium price manifold and any sufficiently close smooth function, the function is a selection from the equilibrium price correspondence for some manifold of economies close to the original one. In particular, the set of equilibria corresponding to any open neighborhood of an economy contains an open subset of the price simplex.
A Universe of Boundaries: Pixilated Performances in Jan Švankmajer’s Food:

Czech surrealist filmmaker Jan Svankmajer is known to animate any sort of thing: leaves, the surface of a wall, socks, nails and raw flesh. But he does not limit himself to inanimate objects; he al...
Prospects for dynamic brake energy recovery on North American freight locomotives

As fuel costs and environmental impacts assume greater importance to railways, so does the importance of options for increased energy efficiency and emissions reduction. A study was conducted on the potential recovery of dynamic brake energy from diesel-electric locomotives in North American freight service. Using computer simulations (Train Energy Model) and locomotive event recorder data, estimations were made of the energy that could be recovered from dynamic brake use. In addition, the differences between the results of the computer simulations with respect to the actual events recorded were examined in order to evaluate how well the model simulates an engineer's operation of locomotives and provide guidance for future improvements to the simulation model. A case study of the energy recovery potential for a Class 1 railroad operating on a major mountain pass in North America was conducted. The route analyzed has two characteristics that make it a good candidate for studying energy recovery potential. First, there is an extended down grade approximately 25 miles long, and second, it has heavy traffic with about 80 trains a day traversing it. Both of these factors enhance the likelihood that investment in energy recovery technology will be economically viable. It was found that the total dynamic brake energy potential was over 1,200 kilowatt-hours per train. Depending on the efficiency of the storage system, as much as 70 gallons of diesel fuel could be saved per train. This equates to 2,800 gallons of fuel a day and a corresponding reduction in emissions. Nevertheless, fuel savings themselves do not provide enough incentive to warrant implementation of dynamic brake energy recovery, but with the addition of environmental cost savings financial benefits may be seen.