cssi/SciSciGPT-SciSciNet huggingface dataset:
The Experience of and Attitude Toward Time in Medieval German Literature from the Early Middle Ages to the Fifteenth Centuries

The present article explores the way how medieval people thought about time and organized their lives in light of the constant passing of time. Whereas modern philosophers and historians have generally credited the Middle Ages with a radically different time concept in contrast to the modern world, here I will argue that occasionally the differences were considerably less stringent and perhaps not even existent. Often, quite naturally, the mental-historical framework was deeply influenced by the Catholic Church which perceived human life within the extremes of life and death, or of secular time and eternity. The analysis will take us from Old High German heroic epic poetry represented by the “Hildebrandslied” with its noteworthy emphasis on the many years in which the father did not see his son, to the late Middle Ages when Oswald von Wolkenstein, through his poetry, and Helene Kottannerin, through her unique diary, indicated their full awareness of the meaning of time in its measurable quality. Not every author reflected the same concept of time, and many of them simply took their readers to the timeless world of King Arthur. Other authors, however, such as the Stricker, expressed a clear idea of time almost in the modern sense of the word by way of positioning their protagonists in problematic situations when they are suddenly pressed for time and need to reach painful decisions.
Post-translational modifications required for coagulation factor secretion and function

Protein translocation into and transport through the secretory pathway in eukaryotic cells is accompanied by a multitude of covalent modifications that occur on the polypeptide backbone. The sequence of post-translational modifications that occur on a polypeptide is carefully regulated both temporally and spatially, where certain modifications only occur within the endoplasmic reticulum (ER) and others only occur within the Golgi compartment (Fig. 1). In many cases these modifications are required for proper polypeptide folding and secretion. In addition, post-translational modifications can affect the half-life of the protein in the plasma and may be required for functional activity of the polypeptide. The mechanisms that direct post-translational modifications recognize specific structural determinants within the polypeptide backbone. The efficiency of these modifications is determined by the specific host cell enzymatic machinery, the availability of substrates and cofactors, as well as structural properties of the polypeptide. To evaluate the role of post-translational modification in protein function investigators have studied proteins treated with chemicals or enzymes to remove modifications, proteins synthesized in the presence of inhibitors of specific modification reactions, proteins expressed in either different cell types or in cell mutants with defects in specific enzymatic machinery required to perform modifications, or proteins engineered through recombinant DNA technology that contain mutations that prevent modifications. The interpretation of results utilizing different strategies needs to be qualified to consider secondary effects due to the approach utilized. As a consequence, it is desirable to utilize several independent approaches to confirm the importance of any specific modification...
Optimal fixed-finite-dimensional compensator for Burgers' equation with unbounded input/output operators

In recent years considerable attention has been devoted to the problem of using feedback to control fluid dynamic systems. This problem is complex and particularly difficult when one is faced with phenomena such as shocks. Moreover, these systems are governed by nonlinear partial differential equations so that the natural state of the system is infinite dimensional. If one assumes that “full state feedback” is necessary to design practical controllers, then one would conclude that feedback control of fluid dynamic system is “not practical”. However, it is well known that even in finite dimensional control systems one rarely has the ability to accurately sense all states, so that some form of dynamic compensation must be used.
Real-Time Quantitative PCR Analysis of Mitochondrial DNA Content

Mitochondrial disorders are a group of complex and heterogeneous diseases that may be caused by molecular defects in the nuclear or mitochondrial genome. The biosynthesis and integrity of the small 16.6-kb mitochondrial genome require a group of nuclear encoded genes. The mitochondrial DNA (mtDNA) depletion syndromes (MDDSs) are autosomal recessive disorders caused by molecular defects in nuclear genes, and characterized by a reduction in mtDNA content. To date, mutations in at least nine genes (POLG, DGUOK, TK2, TYMP, MPV17, SUCLA2, SUCLG1, RRM2B, and C10orf2) have been reported to cause various forms of MDDSs. In the clinical setting, a simple method to determine mtDNA depletion would be useful prior to undertaking gene sequence analysis. This unit outlines the real-time quantitative polymerase chain reaction (qPCR) analysis of mtDNA content in tissues. MtDNA content varies among different tissues and at different ages in the same individual. Detailed protocols for the selection of nuclear genes for normalization, PCR set up, validation procedures, tissue and age matched controls, and sensitivity and specificity in various tissues, as well as interpretation of results are discussed.
A benchmark problem for nonlinear control design: problem statement, experimental testbed, and passive nonlinear compensation

This paper serves three distinct purposes. First, it provides the problem statement for the benchmark problem for nonlinear control design, an invited session which is the basis for six related papers at the conference. The problem considers a translational oscillator with an attached eccentric rotational proof mass actuator, where the nonlinear coupling between the rotational motion of the actuator and the translational motion of the oscillator provides the mechanism for control. Secondly, the paper describes an experimental testbed that has been constructed by the authors to experimentally investigate this problem. Finally, the paper presents the authors' approach to the benchmark problem, which is based on emulation of passive nonlinear mechanical absorbers with single and multiple modes. These controllers are shown to provide asymptotic stability and disturbance rejection with a bounded input signal. Both numerical and experimental results are presented.
Damages and Reliance under Section 10(b) of the Exchange Act

A textualist interpretation of the implied private right of action under Section 10(b) of the Exchange Act concludes that the right to recover money damages in an aftermarket fraud can be no broader than the express right of recovery under Section 18(a) of the Exchange Act. The Act’s original legislative history and recent Supreme Court doctrine are consistent with this conclusion, as is the Act’s subsequent legislative history. Section 18(a), however, requires that plaintiffs affirmatively demonstrate actual “eyeball” reliance as a precondition to recovery and does not permit a rebuttable presumption of reliance. Accordingly, if the Exchange Act is to be interpreted as a “harmonious whole,” with the scope of recovery under the implied Section 10(b) private right being no greater than the recovery available under the most analogous express remedy, Section 18(a), then Section 10(b) plaintiffs must either demonstrate actual reliance as a precondition to recovery of damages, or the Court should revisit Basic, as suggested by four justices in Amgen, and overturn Basic’s rebuttable presumption of reliance. A textualist approach thus provides a rationale for reversing Basic that avoids the complex debate over the validity of the efficient market hypothesis, an academic dispute that the Supreme Court is not optimally situated to referee. Experience also demonstrates that Basic’s presumption of reliance, which is nominally rebuttable, is effectively irrebuttable once it attaches. This observation provides a further basis upon which to challenge Basic’s continuing vitality. The implications of this analysis are potentially profound. If plaintiffs must affirmatively demonstrate actual reliance, then many Section 10(b) securities fraud class actions become uncertifiable because individual questions will predominate. Private securities fraud litigation would then likely be dominated by class actions asserting violations of Section 11 of the Securities Act as well as by a scrum of individual actions brought by larger investors with significant damage claims in major cases. The battle would then likely move to Congress which could legislate a rebuttable presumption of reliance, or otherwise amend the statute to reform the securities litigation process.
Can the Treatment Services Review be used to estimate the costs of addiction and ancillary services

Abstract Purpose: The economic costs of addiction treatment and ancillary services are of great interest to substance abuse treatment providers, researchers, and policymakers. This paper examines whether a widely used treatment evaluation instrument, the Treatment Services Review (TSR), can be used to estimate the costs of addiction and ancillary services. Methods: The fifth edition of the TSR (TSR-5) is carefully reviewed and critiqued for cost estimation purposes. Unit cost estimates and sources are presented for most of the service delivery units on the TSR-5, and important missing service measures are identified. A cost analysis method is proposed that is based on data from the TSR. Results: A variety of unit cost estimates are offered so that researchers and practitioners will understand how this financial information is compiled. However, the investigation determined that the TSR-5 is not currently structured for a comprehensive cost analysis of treatment services. The potential benefits and limitations of the TSR-5 as a cost analysis tool are identified and explained. In addition, recommended changes to the TSR-5 are suggested and described. Implications: Although not originally developed for economic evaluation purposes, with some modifications and enhancements, the TSR is an instrument that is capable of facilitating an economic cost analysis of addiction treatment and ancillary services. By combining service utilization information from a revised TSR (i.e., TSR-6) with reliable unit cost estimates for those services, future evaluation studies will be able to provide more standardized estimates of the costs of addiction and ancillary services for different types of treatment clients. When joined with outcome data, the TSR-6, along with the proposed cost module, can also be used to determine cost-effectiveness and benefit–cost ratios for subgroups of patients and treatment components.
Large-eddy simulation of turbulent flow in a channel with a surface-mounted two-dimensional obstacle using a dynamic subgrid-scale model

We apply the dynamic subgrid-scale model (DSGSM) to large-eddy simulation (LES) of turbulent channel flow with a square rib mounted on one wall. The Reynolds number (Re) is 3210 based on the mean velocity above the obstacle and the obstacle height. Near-wall structures are resolved with the no-slip boundary condition. The results show better agreement with direct numerical simulation (DNS) than LES with a fixed model constant, verifying the value of the DSGSM for simulating complex turbulent flows.
Effect of ethionine on the ultrastructure of developing liver cells.

The effect of ethionine on the ultrastructure of developing liver parenchymal cells of rat has been studied. Despite reports from other studies that ethionine does not alter fetal liver morphology, the present studies show clearly that changes in structure do occur. Mitochondrial dense granules increase, endoplasmic reticulum is disrupted, lipid droplets accumulate, and glycogen deposition is delayed. There is no evidence to date of ductule cell proliferation such as occurs with ethionine poisoning in adult rat.
Predicting Attitudes toward Violence

1. L. A. Guildner, paper presented at the Fifth Symposium on Temperature, Its Measurement and Control in Science and Industry, Washington, D.C., 21 to 24 June 1971. 2. Comite International des Poids et Mesures, Metrologia 5, 35 (1969). 3. H. Plumb and G. Cataland, Int. J. Sci. Metrol. 2, 127 (1966) (see appendix). 4. J. F. Swindells, Ed., Precision Measurement and Calibration, Selected NBS Papers on Temperature (National Bureau of Standards Special Publication 300, Washington, D.C., 1968), vol. 2. 5. L. Haar, paper presented at the Second International Conference on Calorimetry and Thermodynamics, Orono, Maine, 12 to 14 July 1971. 6. T. B. Douglas, J. Res. Nat. Bur. Stand. Sect. A 73, 451 (1969). 7. N. S. Osborne, H. F. Stimson, T. S. Sligh, Jr., C. S. Cragoe, Bur. Stand. U.S. Sci. Pap. No. S.OI (1925). 8. L. Haar, J. Res. Nat. Bur. Stand. Sect. A 72, 207 (1967). 9. H. F. Stimson, personal communication. 10. K. Burgess, J. Res. Nat. Bur. Stand. 1, 635 (1928). 11. H. F. Stimson, ibid. 42, 209 (1949). 12. The very small temperature difference, about 0.010°C, between the triple point and the ice point is readily calculated, and for my purposes I assume that the thermodynamic scale and the practical scale are in agreement at the ice point. 13. Table 4 of (6) includes data for the difference between thermodynamic properties on IPTS. 1968 and ITS-1948. Consider the range 0° to 100'C. From column 3 the maximum value of Cpl/Cp in the range is about 4 X 10-4. From column 2 the maximum value in this range for ,s yields (i/AT)m,, ~ 3 X 10-5. The ratio is about 10. 14. J. F. Masi, H. W. Flieger, J. S. Wicklund, J. Res. Nat. Bur. Stand. 52, 275 (1954). 15. Supported in part by the Office of Standard Reference Data.
Hole filling and hole creation in the superconducting compounds Bi 2 Sr 2 − x R x CuO 6 + y ( R =La, Pr, Nd, and Sm)

The superconducting properties, hole content, and lattice constants of several rare-earth-doped compounds ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2\mathrm{\ensuremath{-}}\mathit{x}}$${\mathit{R}}_{\mathit{x}}$${\mathrm{CuO}}_{6+\mathit{y}}$ have been investigated as a function of rare-earth doping and oxygen content. The maximum superconducting transition temperature, ${\mathit{T}}_{\mathit{c}}$, obtained for each of the rare-earth dopants was 23 K (La), 25 K (Pr), 21 K (Nd), and 12 K (Sm). The ${\mathit{T}}_{\mathit{c}}$'s of these compounds exhibited a parabolic dependence on the La and Pr concentration (0x1), with the maximum ${\mathit{T}}_{\mathit{c}}$ occurring for x=0.4 for samples with low oxygen content. For La- and Pr-doped samples treated in pure oxygen, the position of the maximum shifted to x=0.6 and 0.5, respectively, with a concurrent reduction in the maximum value for ${\mathit{T}}_{\mathit{c}}$ (17 K for La and 18 K for Pr). For xg0.2, the samples were single phase and exhibited unusually sharp superconducting transitions (width of ac-susceptibility transition less than 2 K). The high quality of the samples allowed a precise study of the variation of the orthorhombic cell parameters with the rare-earth and oxygen content.The oxygen content of the samples was systematically varied using oxygen partial pressures that ranged from 100 ppm to 100% oxygen during the heat treatments. Absolute values of the oxygen content and the changes of the oxygen content with heat treatments were determined using thermo- gravimetric analysis. The qualitative features of the dependence of ${\mathit{T}}_{\mathit{c}}$ on x and y can be understood by assuming an excess of holes in the Cu-O planes of the undoped compound that are filled by the extra electrons contributed with rare-earth doping or increased with the addition of oxygen. For La-doped samples treated in pure oxygen there was a smooth variation of ${\mathit{T}}_{\mathit{c}}$ with hole content, with the maximum ${\mathit{T}}_{\mathit{c}}$ (18 K) occurring at a hole content of 0.2\ifmmode\pm\else\textpm\fi{}0.02. For La-doped samples treated in 0.1% oxygen, the maximum ${\mathit{T}}_{\mathit{c}}$ occurred at the same hole content (0.2), but the value of ${\mathit{T}}_{\mathit{c}}$ was significantly higher (23 K). These data illustrate that, even within one alloy system, composition can affect ${\mathit{T}}_{\mathit{c}}$ as well as hole content. Finally, lattice-constant and oxygen-content data from the Pr-doped materials suggest that Pr substituted onto the Sr site has a formal valence of approximately 3.3.
Recasts in parents’ language to their school-age children who stutter: a preliminary study

Abstract Language samples collected from 13 school-age children diagnosed as stutterers (CWS) in conversation with a parent and a similar corpus of data collected from a matched control group of 13 normally-fluent children (CWNS) were analyzed for the quality and quantity of recast usage in the parents’ language. Recasts, a frequently studied type of child-directed language (CDL) pattern hypothesized to increase the length and complexity of young children’s expressive language, have not been studied typically in older children’s conversations with parents nor have they been studied in the CDL of parents of CWS. Comparisons of these samples revealed that both groups of parents were frequent users of imitations, as well as simple and complex type recasts. Indeed, the rank order of recast types used was identical for the two groups of caregivers. When parents’ conversations with the CWS were analyzed further, it was noted that they were not more likely to focus on stuttered utterances as the utterances on which to base their recasts (i.e., “platform utterances”) than on the child’s fluently-produced utterances. These results suggest there is one additional conversation parameter for which there are evident similarities in the CDL used by parents of CWS and CWNS. Clinical implications gleaned from this preliminary study are discussed, as are suggestions for future study. Educational objectives: The reader will learn about and be able to describe (1) the role of recasts in young children’s language development; (2) the types of recasts that were observed in the conversations of parents of CWS and CWNS; and (3) the similarities observed in the recasts produced by parents of CWS and CWNS.
Economic impact of insecticide resistance in the Colorado potato beetle (Coleoptera: Chrysomelidae) on the Michigan Potato Industry

Insecticide resistance in Colorado potato beetle, Leptinotarsa decemlineata (Say), in Michigan was first reported in 1984 but caused severe economic problems beginning in 1991. Surveys conducted by the Michigan Potato Industry Commission and Potato Growers of Michigan from 1991 through 1994 document the increased Colorado potato beetle control costs and yield losses resulting from insecticide resistance. In 1991 and after, statewide mean control costs were as high as $306/ha; costs for districts most seriously affected were as high as $412/ha. This is in contrast to $35-74/ha in the upper peninsula of Michigan, where resistance is not a problem. Yield losses were as high as 12.2% statewide and as high as 20.5% in seriously affected districts. Costs plus losses to the industry were $13.3 million in 1994 (13.7% of crop value). In response to these losses, nearly 100% of the crop was under some type of integrated pest management program. Scouting (96% of crop area) and crop rotation (78% of crop area) were the most common integrated pest management practices. The introduction of new insecticides may reduce or eliminate yield losses. However, costs of resistance will continue to accrue because relatively inexpensive insecticides are no longer effective and newly developed products are up to 5 times more costly. Long-term increased cost to the Michigan industry caused by insecticide resistance in Colorado potato beetle is estimated at $0.9 to $1.4 million/yr ($44 to $69/ha; $18 to 28/acre).
Longitudinal diffusion-weighted imaging changes in children with small bowel Crohn's disease: preliminary experience.

Crohn’s disease has been associated with restricted diffusion in diseased small bowel segments on diffusion-weighted imaging (DWI). However, data addressing longitudinal changes in DWI findings and their potential clinical ramifications in the pediatric population are lacking. The purpose of this study was to follow DWI changes in diseased small bowel segments between serial magnetic resonance enterography (MRE) examinations, and to correlate these changes with other imaging parameters and clinical status. This retrospective study evaluated patients less than 21 years of age undergoing serial MRE examinations including DWI for Crohn’s disease involving the small bowel. All patients carried a diagnosis of Crohn’s disease established by pathology or corroborative clinical and imaging findings. Longitudinal changes in mean apparent diffusion coefficient (ADC) values within the wall of affected small bowel lesions were recorded and normalized to both unaffected bowel and skeletal muscle. ADC changes were correlated with qualitative imaging phenotype, as reflected by a defined set of non-DWI imaging parameters, as well as with clinical disease activity. Seventeen lesions were evaluated longitudinally, distributed among 13 patients (9 boys and 4 girls, mean age at baseline 16.6 years), each of whom had two sequential MRE examinations. Lesions demonstrating a fibrostenotic imaging phenotype at follow-up MRE had a significantly lower change in mean ADC value between examinations than lesions that did not have a fibrostenotic imaging phenotype (p = 0.0005), an effect that persisted when ADC values were normalized to unaffected bowel and skeletal muscle. Across all studies, lesions with a fibrostenotic imaging phenotype had lower ADC values than those with an inflammatory imaging phenotype, which were in turn lower than those with a normal imaging phenotype (p = 0.0001). Patterns of longitudinal DWI changes in Crohn’s disease may differ among small bowel lesions depending upon their specific natural histories. These findings may assist in the evaluation of the ADC value as a potential imaging surrogate when evaluating lesion status, particularly as it pertains to relative contributions of inflammation and fibrosis.
A reduced complexity frequency domain acquisition of DS-SS signals for embedded applications

Most of the current wireless communication devices use embedded processors for performing different tasks such as physical layer signal processing and multimedia applications. Embedded processors provide a reasonable trade-off between application specific implementation and hardware sharing by different algorithms for more optimal design and flexibility. At the same time the widespread popularity of these processors drives the development of algorithms specifically tailored for embedded environments. Fast Fourier Transform (FFT) is a universal tool, which has found many applications in communications and many application specific architectures and Digital Signal Processor (DSP) implementations are available for FFT. In this paper our focus is in embedded algorithms for spread spectrum communication receivers, which are using FFT as an engine to compute convolutions. Using FFT-based correlators one can search over all possible so-called code phases of direct sequence spread spectrum (DS-SS) signal in parallel with fewer operations than conventional correlators do. However in many real-life scenarios the receiver is provided with a timing assistance which confines the uncertainty in code phase within a limited area. The FFT based search is becoming redundant and a reasonable strategy is to modify the FFT based methods for better utilization of embedded processor resources. In this paper we suggest a reduced complexity frequency domain convolution approach for the search over limited number of code phases.
Neuropsychological Performance in Schizophrenics with Histories of Substance Abuse

Both schizophrenia and substance abuse have been associated with cerebral impairment, although the neuro psychological performance of schizophrenic patients with substance abuse histories has not been examined. In this study, the Luria-Nebraska Neuropsychological Battery was administered to schizophrenic patients with or without histories of substance abuse. The study found that the schizophrenics without substance abuse histories showed evidence of cerebral dysfunction, while those schizophrenics with histories of substance abuse could not be differentiated from normal.
On the assumptions underlying theoretical models for flooded porous electrodes

Abstract The consequences of several simplifying assumptions often encountered in theoretical models for porous electrodes are examined by comparison of electrode performance characteristics calculated according to these assumptions with performance predicted by more complete electrode models. The assumptions considered include those of infinite electrode thickness, uniform concentration or conductivity of pore electrolyte, and negligible potential gradient in the pores. The comparisons are based on a metal/metal-hydroxide electrode in binary electrolyte that is generally representative of a large class of battery systems. It is found that all of the assumptions must be invoked with caution. In particular, the assumption of uniform electrolyte concentration has a very restricted range of validity while that of uniform conductivity, when combined with proper treatment of diffusion potentials, can be used effectively over a much greater set of conditions.
Upregulation of p55 and p75 Receptors Mediating TNF-α Transport Across the Injured Blood-Spinal Cord Barrier

Tumor necrosis factor (TNF-α) is involved in the inflammation and tissue regeneration occurring after spinal cord injury (SCI). This study tests the specific role of p55 and p75 receptors in mediating the transport of TNF-α across the blood-spinal cord barrier (BSCB) after SCI by compression. Transcytosis of 125I-TNF-α across a monolayer of the cerebral endothelial cells that compose the blood-brain barrier was significantly reduced in the absence of functional p55 and p75 receptors. At 3 d after SCI, double receptor knockout mice had a significantly reduced increase in TNF-α uptake from blood to injured lumbar spinal cord as compared with their inbred controls, despite the similar extent of BSCB disruption (measured by 99mTc-albumin). The p75 single receptor knockout mice had a reduced increase in 125I-TNF-α uptake, whereas the p55 receptor knockout mice had no significant increase of 125I-TNF-α uptake after SCI, suggesting that the p55 receptor plays a major role. Hence, the increased uptake of TNF-α 3 d after SCI is not explained by nonspecific barrier disruption but by receptor-mediated upregulation of transport. Quantitative RT-PCR analysis further showed that upregulation of TNF-α transport was related to increased expression of mRNA for p55 and p75 receptors. The increase of p55 receptor expression was more robust and seen between 12 h and 1 wk after SCI, whereas the increase of p75 receptor expression occurred later and involved fewer regions. Thus, the differential upregulation of p55 and p75 receptors indicates that permeation of TNF-α across the injured BSCB remains a regulated process. Knowledge of receptor-mediated regulation could facilitate effective therapeutic manipulation of BSCB permeation of vascular cytokines important to CNS regeneration.
Stalinism, revisionism and the problem of conceptualisation: A review article

(1988). Stalinism, revisionism and the problem of conceptualisation: A review article. Soviet Studies: Vol. 40, No. 3, pp. 501-505.
Processing, Structure, and Properties of PAN/MWNT Composite Fibers

Conventional dry-jet wet fiber spinning techniques were used to fabricate continuous PAN/ MWNT composite fibers with up to 20 wt.-% nanotube loading. PAN at the MWNT interface exhibited lower solubility under thermodynamically favorable conditions than in bulk PAN, indicating good interfacial interaction. Due to the PAN/MWNT interaction at the interface, thermal shrinkage decreases with increasing MWNT loading (5 to 20 wt.-%). For high MWNT loadings, PAN/ MWNT composite fiber at 15 wt.-% MWNT loading showed an axial electrical conductivity of 1.24 S·m ―1 . For all loadings, PAN/MWNT composite fibers exhibited higher tensile moduli than theoretically predicted by rule-of-mixture calculations, suggesting good reinforcement of the PAN by MWNT.
Hunting Behavior and Strategies of the Valley Bisa in Zambia

This article describes the hunting tactics and prey selection of the Valley Bisa, a matrilineal, subsistence-oriented society in the Luangwa Valley of Zambia. Although Valley Bisa hunters explain their behavior in their own idioms, many of their tactics, including the stimuli for and timing of hunts, the circular morphology of their hunting patterns, and randomized searches, appear functionally related to the behavior and ecology of their prey. The effects of outlawing traditional harvest techniques and the imposition and enforcement of external constraints on Valley Bisa hunting patterns are discussed. Data on habitats, density of cover, wind direction, species, and initial distance to prey from 50 hunts, in which 16 mammals were killed, are compared and related to success and failure of stalking attempts. Graphs, comparing the numbers of observations for each of four variables with the frequency of stalking attempts, illustrate the cultural style of predation for this group of hunters.
Multislice ex vivo thermoacoustic imaging of porcine kidneys

We have added multi-slice acquisition capability to our thermoacoustic testbed. Thermoacoustic signal is generated because test specimens selectively absorb pulsed electromagnetic energy producing rapid thermal expansions that generate ultrasonic pulses. Filtered back-projection reconstruction yields images over an 8 cm field of view. Preliminary reconstructions of porcine kidneys track slice-to-slice progression of calyces, although renal pyramids are not well visualized.
Building agent teams using an explicit teamwork model and learning

Multi-agent collaboration or teamwork and learning are two critical research challenges in a large number of multi-agent applications. These research challenges are highlighted in RoboCup, an international project focused on robotic and synthetic soccer as a common testbed for research in multi-agent systems. This article describes our approach to address these challenges, based on a team of soccer-playing agents built for the simulation league of RoboCup—the most popular of the RoboCup leagues so far. To address the challenge of teamwork, we investigate a novel approach based on the (re)use of a domain-independent, explicit model of teamwork, an explicitly represented hierarchy of team plans and goals, and a team organization hierarchy based on roles and role-relationships. This general approach to teamwork, shown to be applicable in other domains beyond RoboCup, both reduces development time and improves teamwork flexibility. We also demonstrate the application of off-line and on-line learning to improve and specialize agents' individual skills in RoboCup. These capabilities enabled our soccer-playing team, ISIS, to successfully participate in the first international RoboCup soccer tournament (RoboCup'97) held in Nagoya, Japan, in August 1997. ISIS won the third-place prize in over 30 teams that participated in the simulation league.
EFFECTS OF LEPTIN ON INSULIN SENSITIVITY IN NORMAL RATS

To determine whether leptin has insulin sensitizing effects in normal rodents, we measured plasma glucose and insulin concentrations in male Sprague-Dawley rats treated with leptin or vehicle by continuous s.c. infusion for 48 h. In additional experiments, we examined the acute effect of i.v. leptin upon insulin sensitivity under conditions of clamped glycemia. Subcutaneous leptin was administered at 10.0 and 1.0 microg/h. To avoid confounding effects of differences in food intake, both leptin- and vehicle-treated rats were fasted during the 48-h period of infusion. Infusion of leptin, 10 microg/h, significantly reduced both plasma glucose and insulin. Leptin, 1.0 microg/h, also decreased plasma glucose and insulin, although the effects on insulin did not achieve statistical significance. Leptin at either dose did not alter body weight or epididymal fat mass compared with vehicle treated controls. Leptin, 10 microg/h, decreased circulating insulin-like growth factor-1 levels. No differences in GLUT-4 content in either in brown or epididymal fat were observed as a result of leptin-treatment. Leptin, 10 microg/h, significantly decreased urine osmolality, increased water intake, and reduced renal potassium excretion compared with vehicle-infused rats. In additional rats, we measured the acute effect of i.v. leptin on insulin sensitivity determined as whole body glucose utilization during hyperinsulinemic glucose clamps performed at glucose targets of 60 and 90 mg/100 ml. Glucose utilization was increased by 29% during the last 135 min of glycemia clamped at 60 mg/100 ml (P < 0.05) and by 30% during the last 135 min of glycemia clamped at 90 mg/dl (P < 0.01) in rats infused with leptin compared with vehicle. In summary, leptin increased insulin sensitivity in normal rats both under fasting conditions and in the presence of hyperinsulinemia at clamped glucose. These effects did not appear dependent on altered body weight. Leptin also altered salt and water metabolism under fasting conditions resulting in increased water intake and more dilute urine.
Splat feature classification: Detection of the presence of large retinal hemorrhages

Reliable detection of large retinal hemorrhages is important in the development of automated screening systems which can be translated into practice. In this study, we propose a novel large retinal hemorrhages detection method based on splat feature classification. Fundus photographs are partitioned into a number of splats covering the entire image. Each splat contains pixels with similar color and close spatial location. A set of distinct features is extracted within each splat. By learning properties of splats formed from blood vessels, a classifier was trained so that it can distinguish blood splats from non-blood splats. Once the blood splats, i.e. vasculature and hemorrhages, are separated from the background, the connected vasculature was removed and the remaining objects considered hemorrhage candidates. Our approach had a satisfactory performance on a test set composed of 1200 images compared to a human expert.
Effect of the insecticides toxaphene and carbaryl on induction of lung tumors by benzo[a]pyrene in the mouse

The insecticides toxaphene and carbaryl, when fed in the diet alone for 20 wk, were not tumorigenic to female All mice. Dietary levels of these insecticides were investigated for their effects on the incidence of lung tumors induced by oral administration of benzo[a]pyrene (BP). A significant reduction in BP‐induced lung tumors was found after feeding 100 ppm toxaphene for 12 wk or 200 ppm for 20 wk. In contrast, 1000 ppm carbaryl fed for 20 wk caused a significant enhancement of BP‐induced lung tumors. Mice that received toxaphene in the diet alone, or toxaphene and BP, showed an increase in BP hydroxylase activity in the liver and a decrease in enzyme activity in the lung. Carbaryl and BP increased BP hydroxylase activity in the lung without altering enzyme activity in the liver. Inhibition of lung BP hydroxylase activity was paralleled by a reduction in BP‐induced lung tumors in mice fed toxaphene. Conversely, increased lung BP hydroxylase activity was associated with an enhancement of BP‐induced lung ...
The role of brush spring kinking in a generator flash-over incident

Mechanical analysis and testing of a brush holder and its spring-operated, brush-advancing mechanism revealed a design deficiency in the spring assembly. The deficiency was due to the use of a double-layer constant force spring, which kinked. This design deficiency, in combination with adhesive contamination trapped between the spring layers, lead to mechanical obstruction of the brush travel path. If electrical and mechanical contact with the surface of the generator collector rings is compromised, brush wear accelerates, generating conductive debris. Furthermore, the remaining brushes must carry more electrical current, resulting in localized heating. Both the wear debris, which was allowed to accumulate, and localized heating likely contributed to a destructive flashover in a near-new 230-MW generator.
On modelling the performance and reliability of multimode computer systems

We present an effective technique for the combined performance and reliability analysis of multimode computer systems. A reward rate (or a performance level) is associated with each mode of operation. The switching between different modes is characterized by a continuoustime Markov chain. Different types of service-interruption interactions (as a result of mode switching) are considered. We consider the execution time of a given job on such a system and derive the distribution of its completion time. A useful dual relationship, between the completion time of a given job and the accumulated reward up to a given time, is noted. We demonstrate the use of our technique by means of a simple example.
On the number of irregular assignments on a graph

Abstract Let G be a simple graph which has no connected components isomorphic to K1 or K2, and let Z + be the set of positive integers. A function ω: E(G)→ Z + is called an assignment on G, and for an edge e of G, ω(e) is called the weight of e. We say that w is of strength s if s = max{ω(e): e ϵ E(G)}. The weight of a vertex in G is defined to be the sum of the weights of its incident edges. We call assignment w irregular if distinct vertices have distinct weights. Let Irr(G,λ) be the number of irregular assignments on G with strength at most λ. We prove that |Irr(G, λ) − λ q + c 1 λ q−1 |= O(λ q−2 ), λ→∞ where q =|E(G)| and c1 is a constant depending only on G. An explicit expression for c1 is given. Analysis of this expression enables us to determine which graph with q edges has the least number of irregular assignments of strength at most λ, for λ sufficiently large.
Protonation reactions and their coupling in bacteriorhodopsin

Light-induced changes of the proton affinities of amino acid side groups are the driving force for proton translocation in bacteriorhodopsin. Recent progress in obtaining structures of bacteriorhodopsin and its intermediates with an increasingly higher resolution, together with functional studies utilizing mutant pigments and spectroscopic methods, have provided important information on the molecular architecture of the proton transfer pathways and the key groups involved in proton transport. In the present paper I consider mechanisms of light-induced proton release and uptake and intramolecular proton transport and mechanisms of modulation of proton affinities of key groups in the framework of these data. Special attention is given to some important aspects that have surfaced recently. These are the coupling of protonation states of groups involved in proton transport, the complex titration of the counterion to the Schiff base and its origin, the role of the transient protonation of buried groups in catalysis of the chromophore's thermal isomerization, and the relationship between proton affinities of the groups and the pH dependencies of the rate constants of the photocycle and proton transfer reactions.
The effect of ash on runoff and erosion after a severe forest wildfire, Montana, USA

Ash formed by the combustion of vegetation and the litter and duff layers may affect runoff and erosion rates in the period immediately following wildfires, but only a handful of studies have specifically measured its effect. Approximately 1 month after the 2005 Tarkio Fire in western Montana, we applied simulated rainfall for 1 h at a mean intensity of 7.5 cm h–1 to six pairs of 0.5-m2 plots in an area burned at high severity and with a continuous 1-cm to 3.5-cm ash layer on the surface. The ash was retained in one plot per pair and removed from the other plot with a fine brush. The ash layer provided an additional 1.5 cm of water storage capacity and protected the underlying mineral soil from surface sealing, so that the time of ponding in the ash-covered plots was 12 ± 10 min longer, the final runoff rate was 2.1 ± 0.4 cm h–1 lower and the total infiltration was 2.0 ± 1.2 cm higher than in the plots without ash. The reduced runoff from the ash-covered plots in combination with reduced rainsplash detachment resulted in a 74% reduction in sediment yield relative to the plots without ash. Nine months after the fire, the ash was patchy and just a few millimetres thick, and a second set of simulations showed no significant differences in the time of ponding, final runoff rate, total infiltration or sediment yield between plots with and without ash. Ash may significantly reduce the runoff and erosion from severely burned areas in the period shortly after a fire. Consequently, the largest post-fire hydrogeomorphic hazard will occur after the ash layer has been removed by wind and water erosion, but before there has been substantial vegetative regrowth.
Slow evoked cortical potentials and temporal features of stimulation.

Abstract Slow cortical responses were evoked from human subjects by either shocks or clicks. Electrodes were at the vertex and the right mastoid region. Various temporal features of stimulation were explored, such as regularity of stimulus intervals, the duration of these intervals, background stimulation rate and the effect of prolonged exposure to stimulation. In general, the amplitude of response (N1−P2) is considerably increased by lengthening the intervals between stimuli. The last interval is the most important but the mean interval, over the prior 10 sec, is also significant. The “recovery process” for shocks appears to be faster than for clicks. Irregularity of stimulation per se gives only a slight enhancement. Our detailed conclusions follow. 1. 1. Introduction of irregularity into the intervals between stimuli (with rate of stimulation held constant at 4 per 10 sec) slightly enhanced the responses to shocks and to clicks. 2. 2. Decreasing the rate of stimulation (for shocks), regardless of whether stimuli were regularly or irregularly spaced, caused increase of amplitude. Completely recovery of amplitude occurred when shocks were less frequent than 4 per 10 sec. The length of the last interval before a shock had a strong effect on the response amplitude. 3. 3. With the interval preceding the stimulus of interest held constant at 2.5 sec, a decrease in the over-all rate of clicks from 8 to 4 to 2 per 10 sec increased the amplitude of the responses. 4. 4. Prolonged exposure to stimulation for many minutes caused a systematic decline in response amplitude for shocks, but no noticeable decline for clicks. 5. 5. Individual exceptions appeared to all of these general statements, sometimes erratically, sometimes associated with particular subjects.
Excimer formation as the relaxation of a non-linear oscillator. I. Model calculations in a linear chain

Abstract The process of excimer formation in molecular crystals is studied through a model calculation of the vibrational relaxation of a non-linear oscillator. The crystal is modelled as a linear chain of molecules interacting via harmonic forces with the exception of the excimer-forming molecular pair. This pair has the same harmonic interaction as the rest of the chain when electronically unexcited but, when excited, is assumed to interact via a highly non-linear force. We treat both the case of a single spring constant throughout the unexcited chain and that of two alternating spring constants. We solve the classical problem of the relaxation of the pair for various forms of the non-linearity and discuss the relaxation time, early time spectra, and related issues.
Experimental Evidence for Self-Limiting Reactive Flow through a Fractured Cement Core: Implications for Time-Dependent Wellbore Leakage

We present a set of reactive transport experiments in cement fractures. The experiments simulate coupling between flow and reaction when acidic, CO2-rich fluids flow along a leaky wellbore. An analog dilute acid with a pH between 2.0 and 3.15 was injected at constant rate between 0.3 and 9.4 cm/s into a fractured cement core. Pressure differential across the core and effluent pH were measured to track flow path evolution, which was analyzed with electron microscopy after injection. In many experiments reaction was restricted within relatively narrow, tortuous channels along the fracture surface. The observations are consistent with coupling between flow and dissolution/precipitation. Injected acid reacts along the fracture surface to leach calcium from cement phases. Ahead of the reaction front, high pH pore fluid mixes with calcium-rich water and induces mineral precipitation. Increases in the pressure differential for most experiments indicate that precipitation can be sufficient to restrict flow. Exper...
A Simple Azimuth and Phase Half-Shade of Variable Sensitivity

The azimuth half-shade component consists of two thin adjoining glass plates mounted on and in front of the analyzer at an angle of about 90° with each other. The common edge is in the plane of polarization of the analyzer, the glass strips making equal angles with this plane. The phase half-shade component is an approximately quarter-wave mica plate placed in front of the glass slips (away from the analyzer), its planes of polarization being in and perpendicular to that of the analyzer. It is so cut and mounted that its free edge bisects the field of view in a line perpendicular to the common edge of the glass slips. End-point setting is complete when (1) the intensities in adjacent quadrants in the field of view not back of the mica phase plate are equal (azimuth), and (2), they are also equal in the quadrants back of the mica. Azimuth and phase sensitivity are both varied equally by changing the angle of inclination of the common edge of the glass slips with the axis of rotation of the analyzer. Due to the method of construction, all adjustments for proper operation can be made optically at any time. No high constructive skill is needed in making the apparatus and the preliminary adjustments are not critical. The photometric dividing line between quadrants for both settings (1) and (2) is one obtuse adjoining edge of one of the glass slips which is easily made imperceptible. The sensitivity in both azimuth and phase is equal to that of any of the usual variable sensitivity half-shade devices.
OPERATING POLICIES FOR SCHEDULING ASSEMBLED PRODUCTS

This paper describes a simulation study of the relative impact of different operating policies on performance of a hypothetical multistage production system that produces assembled products. The main objective of this study is to examine the impact of operating policy rules on system performance. Several performance criteria, including flow time and earliness and tardiness measures, were used to evaluate system performance. Results show that performance of the production system is significantly influenced by the operating policy rules, although the relative impact of the rules is dependent on the performance measure considered. Interactions between and among policy rules were also found to be important in several cases. Overall, the results indicate that much previous research in non-assembly systems can be generalized to assembly systems. Subject Areas: Scheduling, Material Requirements Planning, and Simulation.