cssi/SciSciGPT-SciSciNet huggingface dataset:
The Dual Class Spectrum

The debate over dual-class companies is longstanding and ongoing. However, scholars and regulators generally treat the question of whether a company is dual class as a binary one. If a company grants certain shareholders a separate class of stock with disproportionate voting rights, then the company is treated as a dual-class company. A company with only a single class of stock is never treated as dual class because it is assumed that the shareholders in a single-class company are treated equally. This Article uses an original data set to provide a new perspective on the dual-class debate by showing that treating the distinction between dual-class and single-class as binary has caused scholars and regulators to miss the myriad ways in which insiders receive rights that are not available to public shareholders. The authors’ data set shows the wide spectrum of control rights that purportedly single-class corporations grant to insider shareholders by contract rather than through high-vote stock. In fact, companies grant special rights to insiders through contractual mechanisms much more commonly than they do so through traditional dual-class structures. Based on these findings, the Article makes the novel argument that single-class companies that grant disproportionate control rights to insider shareholders by contract are single-class in form, but dual-class in substance, which, problematically, allows them to avoid the scrutiny and restrictions that protect public shareholders in traditional dual-class companies. These insights have important implications for policymakers, scholars, and investors. For example, the SEC has engaged in various attempts to regulate high-vote dual-class structures, and many institutional investors and indices have placed trading restrictions on their shares. However, these attempts to reduce investment in companies that grant insiders disproportionate control rights apply exclusively to high-vote dual-class companies and therefore have lacked the nuance necessary to match insiders’ sophistication. This Article provides a framework that will make it possible to account for the full complexity of ways in which insiders use dual-class structures, either explicitly or implicitly.
Simulation of pellet ELM triggering in low-collisionality, ITER-like discharges

3D nonlinear, as well as 2D linear M3D-C1 simulations are used to model ELM triggering by small pellets in DIII-D discharges in the ITER relevant, peeling-limited pedestal stability regime. A critical pellet size threshold is found in both experiment and modeling depending on pedestal conditions, pellet velocity and injection direction. Using radial injection at the outboard midplane, the threshold is determined by M3D-C1 for multiple time slices of a DIII-D low-collisionality discharge that has pellet ELM triggering. Experimental observations show that a larger pellet size than the standard 1.3 mm diameter is necessary for ELM triggering; 1.8 mm pellets triggered several ELMs in cases where a smaller pellet failed. The M3D-C1 simulations are in good agreement with these observations. While the 2D linear simulations give insight into the change of growth rates for various toroidal modes with pellet size, the 3D nonlinear simulations apply a pellet ablation model that mimics the actual injection with good match to the experiment. The 3D nonlinear simulation confirms the pellet ELM triggering for a pellet size larger than the threshold found by the linear simulations.
Tradition and Diversity Among the Prehistoric Hunters and Gatherers of Southern Texas

Archaeological and ethnohistorical research has been greatly accelerated in southern Texas in the past five years. A new body of data obtained through extensive surveys, major excavations and intensified archival studies make possible a more detailed view of the area's 11,000-year record of hunting and gathering lifeways. We can begin to replace the model of a widespread, homogenous prehistoric cultural pattern (and the early historic "Coahuiltecan" stereotype) with a more realistic perspective which documents regional and temporal variations. While a hunting and gathering subsistence tradition dominated the de velopment of prehistoric lifeways, there is now substantial evidence of intraregional cultural diversity. Such diversity was the result of both spatially- and temporally-localized resources within the area, and perhaps of shifting spheres of extra-areal cultural influences. New geomorphological, climatic, and chronometric data also permit us to examine certain aspects of both tradition and diversity within a suitable chronological framework.
Drift and Regularity

Using the finiteness of the invariant measure to classify two different levels of stability is intuitively appealing. It is simple, and it also involves a fundamental stability requirement of many classes of models. Indeed, in time series analysis for example, a standard starting point, rather than an end-point, is the requirement that the model be stationary, and it follows from (10.4) that for a stationary version of a model to exist we are in effect requiring that the structure of the model be positive recurrent.
HOST-PARASITE RELATIONSHIPS AMONG GROUP A STREPTOCOCCI II. Influence of Sex on the Susceptibility of Inbred Mice Toward Streptococcal Infection

Abstract Willoughby, Donald S. (University of Minnesota, Minneapolis), and Dennis W. Watson. Host-parasite relationships among group A streptococci. II. Influence of sex on the susceptibility of inbred mice toward streptococcal infection. J. Bacteriol. 87:1457–1461. 1964—BALB/Sy mice showed marked sex differences in susceptibility to a strain of Streptococcus pyogenes type 18. Castration of the highly susceptible normal adult male increased their resistance 1,000-fold, which approximated that of normal female mice. Treatment of male mice with estrogen and stilbestrol did not affect their resistance significantly. Young, sexually immature male mice, 4 weeks old, were more resistant than mature males. Susceptibility of the resistant females was not affected by age or bilateral ovariectomy, but testosterone injections caused an increase in susceptibility. Treatment of male mice with estrogen and stilbestrol did not modify their resistance. Smears of peritoneal exudates from normal male mice after intraperitoneal injection of streptococci revealed rapid multiplication of the organisms. There was no evidence of multiplication in the resistant normal female and castrated male mice.
X-ray laser based on channel radiation

A relativistic electron beam propagating through planar or axial channels in a crystal can populate bound transverse energy eigenstates. Spontaneous dipole transitions between these discrete eigenstates lead to narrow-width, highly polarized X-rays that are strongly forward peaked in intensity. To obtain an observable gain from induced emission, the electron beam current density must be 10/sup 7/-10/sup 8/ A/cm/sup 2/ for one-pass amplification. The authors discuss several ways to reduce this current density requirement. The net result of the analysis is that observable gain should be possible for an electron beam current density of 10/sup 4/-10/sup 5/ A/cm/sup 2/. To achieve such a current density, consider a field emission electron gun similar to that used for scanning electron microscopy. The authors have also studied several methods of accelerating the beam and increasing the current without increasing the transverse energy of the beam by using a pulsed source. >
Magnetic Circular Dichroism of Co(II) Carbonic Anhydrase

The magnetic circular dichroism (MCD) induced in the visible absorption bands of Co(II) carbonic anhydrase by a 45 kilogauss magnetic field is described. Based on a comparison to the absorption and MCD spectra of Co(II) in tetrahedral, distorted tetrahedral, and octahedral ligand fields, band assignments are made for both the active alkaline form of the Co(II) enzyme and its anion complexes. The MCD shows that all anion complexes appear to have similar if not identical molecular geometry around the cobalt ion which generates a nearly tetrahedral ligand field. It is proposed that the active alkaline form of the Co(II) enzyme is a trigonally distorted tetrahedron. The relationship of these coordination geometries to the mechanism of action is discussed.
Die Innervation der Niere

Die Versorgung der Niere mit Nerven ist auserordentlich reich. Von den Organen der Baucheingeweide wird sie wohl darin nur noch von der Nebenniere ubertroffen.
A non-icosahedral T2 (Al6Li3Cu) phase

T2 (Al6Li3Cu) precipitates formed by solid-state reactions in an Al-Li-Cu ternary alloy have been studied by convergent-beam electron diffraction (CBED). Asymmetries observed in the CBED patterns i...
Human-robot interaction and related social/ethical issues

Summary form only given. This talk describes both broad ethical and social perspectives on the development of robotic systems and their implications for business, as well as ongoing research on various ways in which humans can be engaged with robots. One approach enables average people to easily specify and execute multiagent military robotic missions using the MissionLab system developed at Georgia Tech. Another perspective involves engaging users directly with robots through affective (emotional) bonding. Finally the notion of just what robots ultimately should be is considered from a social and ethical perspective.
Pulse-front tilt caused by spatial and temporal chirp

Pulse-front tilt in ultrashort laser pulses is usually considered equivalent to angular dispersion. We prove, however, that the combination of spatial and temporal chirp also produces pulse-front tilt. We verify this experimentally using a GRENOUILLE.
Childhood Poverty and Recruitment of Adult Emotion Regulatory Neurocircuitry

One in five American children grows up in poverty. Childhood poverty has far-reaching adverse impacts on cognitive, social and emotional development. Altered development of neurocircuits, subserving emotion regulation, is one possible pathway for childhood poverty's ill effects. Children exposed to poverty were followed into young adulthood and then studied using functional brain imaging with an implicit emotion regulation task focused. Implicit emotion regulation involved attention shifting and appraisal components. Early poverty reduced left dorsolateral prefrontal cortex recruitment in the context of emotional regulation. Furthermore, this emotion regulation associated brain activation mediated the effects of poverty on adult task performance. Moreover, childhood poverty also predicted enhanced insula and reduced hippocampal activation, following exposure to acute stress. These results demonstrate that childhood poverty can alter adult emotion regulation neurocircuitry, revealing specific brain mechanisms that may underlie long-term effects of social inequalities on health. The role of poverty-related emotion regulatory neurocircuitry appears to be particularly salient during stressful conditions.
Jugular Venous Pulse in 2:1 Atrioventricular Block

Abstract Five patients with 2:1 atrioventricular block were observed at bedside to have prominent a waves in their jugular venous pulse occurring before their conducted beats. Two of these patients...
On knot-like groups and ribbon concordance

Abstract We consider the following conjecture of E.S. Rapaport: If G is a knot-like group and its commutator subgroup G′ is finitely generated, then G′ is free. We prove this for any knot-like 3-manifold group. We also prove Rapaport's conjecture for the group of any ‘efficient’ ribbon concordance. Consequently, for any efficient ribbon concordance from K 1 to K 0 with K 1 fibered, K 0 is also fibered.
Reconstitution mechanisms in the radiolysis of aqueous biochemical systems: inhibitive effects of thiols.

THE hydrated electron, e−aq, and the OH radical are the principal products of the radiation induced decomposition of liquid water; with gamma rays the 100 eV yields1 of these reactive intermediates are closely approximated by the values Ge−aq ≃ GOH ≃ 2.6. While certain classes of organic compounds are known to react quantitatively with both e−aq and OH in oxygen-free solution, the observed yield for net destruction of such solutes may be quite low compared with the G value for water decomposition. In interpreting the radiation chemistry of such systems the concept of a reconstitution or back-reaction must be invoked.
Serious and lethal respiratory tract infections of viral etiology in children.

Viruses may lead to serious and lethal pulmonary infections in immunocompetent and immunocompromised children. Series of children with acute respiratory distress syndrome and series of children requiring extracorporeal membrane oxygenation, as well as reported series of nosocomial viral illness, offer an insight into the extent of serious viral disease documented in the medical literature. Series of children with specific viral respiratory illness also will be reviewed, as will the means of diagnosis in these groups of patients. Copyright © 2000 by W.B. Saunders Company.
A new method of interpretation of the ferric chloride oxidation patterns of the urobilinoids.

Abstract A new and more definitive interpretation of the results of a standard method of FeCl 3 oxidation of the urobilinoids is presented. This interpretation is based on the actual yields of mesobiliviolin, glaucobilin, or unchanged urobilinoid. The yields are used to calculate the two distinctive ratios characteristic of urobilinoid type. Correction is made for the effects due to overlapping of spectra and the method has been programmed for a digital computer. Blind analyses of appropriate known mixtures of l -stercobilin, mesobiliviolin, and glaucobilin have given satisfactory results. Comparison of the ratios following FeCl 3 oxidation of binary mixtures of representative urobilinoids permits analysis of their composition. Evidence is presented that the FeCl 3 method involves two types of oxidation: (a) Dehydrogenation to mesobiliviolin and glaucobilin, the extent of oxidation depending on saturation or unsaturation of the end rings. Stercobilin, with both end rings saturated, yields neither mesobiliviolin or glaucobilin; half-stercobilin with one end ring saturated yields stable mesobiliviolin and unreacted urobilinoid; and the urobilins proper, with both end rings unsaturated, are converted first to labile mesobiliviolin then to glaucobilin. (b) All three types also undergo some degradative oxidation as indicated by the presence of ethylmethylmaleimide from unsaturated, and ethylmethylsuceinimide from saturated end rings.
Characterization of Young's modulus of silicon versus temperature using a ``beam deflection'' method with a four-point bending fixture

Abstract Young’s modulus ( E ) and Poisson’s ratio ( ν ) are dependent upon the direction on the silicon surface. In this work, E and ν of silicon have been calculated analytically for any crystallographic direction of silicon by using compliance coefficients ( s 11 , s 12 , and s 44 ), and the values of E are confirmed experimentally by using a “beam deflection” method with a four-point bending fixture. Experimental results for E as a function of temperature from −150 °C to +150 °C are presented for (0 0 1) and (1 1 1) silicon wafers.
760 Stress in Pediatric Residency, 1984s An Occupational Hazard

The occupational stresses inherent in residency training have seldom been empirically evaluated. A survey designed to quantify characteristics of a residency program and its stresses was mailed to 56 PL 1-3 residents at a large children's hospital. Additionally, age, sex, marital status, hours worked per week and hours of sleep at home and “on call” were noted. Stress was measured with the Osipow & Spokane's (1983) Occupational Environments Scales. This instrument, composed of sixty statements, estimates six aspects of occupational stress: role overload (demands >personal resources), role insufficiency (perception of inappropriateness of skills), role ambiguity (lack of clarity of expectations), role boundry (conflicting role demands), role responsibility (perception of responsibility), and characteristics of the physical environment. Four of 6 indices were different (p<0.01) from expected normative responses. Resident stress appeared to be related to problems of role overload, role responsibility, and the physical evironment; while one index, role insufficiency was significantly lower than expected. Interns were the most stressed in terms of role insufficiency and ambiguity. Hours worked per week for PL-1, 2, and 3 were 89.7, 81.6, and 74.1 respectively while average sleep on call was 2.5 hrs vs 7 at home. A “Reactions to Night Call Index” showed no differences between PL-1, 2 and 3's. Quantifying the stresses of a residency program provides a basis for the implementation of interventions to reduce stress.
Positive Psychotherapy for Smoking Cessation: A Pilot Randomized Controlled Trial.

Objective: Greater depressive symptoms and low positive affect (PA) are associated with poor smoking cessation outcomes. Smoking cessation approaches that incorporate a focus on PA may benefit smokers trying to quit. The purpose of this study was to conduct a pilot randomized clinical trial to compare standard smoking cessation treatment (ST) with smoking cessation treatment that targets positive affect, termed positive psychotherapy for smoking cessation (PPT-S). Method: Smokers who were seeking smoking cessation treatment were assigned by urn randomization to receive, along with 8 weeks of nicotine replacement therapy, either ST (n = 31) or PPT-S (n = 35). Seven-day point prevalence smoking abstinence was biochemically confirmed at 8, 16, and 26 weeks. Results: Compared to ST, a greater percentage of participants in PPT-S were abstinent at 8 weeks, 16 weeks, and 26 weeks, but these differences were nonsignificant. In a more statistically powerful longitudinal model, participants in PPT-S had a significantly higher odds of abstinence (adjusted odds ratio [AOR] = 2.75; 95% CI = 1.02, 7.42; p = .046) across follow-ups compared to those in ST. The positive effect of PPT-S was stronger for those higher in PA (OR = 6.69, 95% CI = 1.16, 38.47, p = .03). Greater use of PPT-S strategies during the initial 8 weeks of quitting was associated with a less steep decline in smoking abstinence rates over time (OR = 2.64, 95% CI = 1.06, 6.56, p =.04). Conclusion: This trial suggests substantial promise for incorporating PPT into smoking cessation treatment.
Layered Light Field Reconstruction for Defocus Blur

We present a novel algorithm for reconstructing high-quality defocus blur from a sparsely sampled light field. Our algorithm builds upon recent developments in the area of sheared reconstruction filters and significantly improves reconstruction quality and performance. While previous filtering techniques can be ineffective in regions with complex occlusion, our algorithm handles such scenarios well by partitioning the input samples into depth layers. These depth layers are filtered independently and then combined together, taking into account inter-layer visibility. We also introduce a new separable formulation of sheared reconstruction filters that achieves real-time preformance on a modern GPU and is more than two orders of magnitude faster than previously published techniques.
Effect of androgens on adrenal cortical 11β-hydroxylation

Abstract The effects of the chronic administration of testosterone, androstenedione and DHA upon adrenal cortical function in the rat were compared. Only testosterone induced hypertensive disease and decreased 11β- and 18-hydroxylase activity in vitro. Significant decreases in adrenal mitochondrial cytochrome P-450 levels were apparent in all androgen-treated groups. Testosterone administration also resulted in a significant increment in the concentration of cytochromes a + a3. The DOC-induced difference spectrum was reduced in all androgen-treated groups when expressed per mg of protein but only in mitochondria from testosterone-treated rats when calculated per nanomole of cytochrome P-450. The results suggest that the inhibition of the 11β- and 18-hydroxylation of DOC by testosterone is the result of competitive binding to cytochrome P-450 and not the induced decrease in cytochrome P-450 levels per se.
Parallel Petri net path searching on a local area network—Object oriented Pascal implementation

Abstract In this increasingly technological age, the need for parallel processing has never been greater than it is today. Parallelizing a particular program or system can increase the speed of the system by the number of processors (in the ideal case). A wide variety of parallel and distributed systems exist, and their efficiency may not be the same for different types of problems. In fact, the variation of real world systems and their possible implementation on an actual distributed system is enormous. In this paper, an inexpensive solution to parallelizing the determination of paths in a Petri net is presented. The system utilized is an IBM Local Area Network with four computers arranged as a parallel processing system. A three step generalized algorithm to accomplish the parallelization is given. The actual implementation is facilitated by the use of object oriented software design, in particular Turbo Pascal version 5.5 (which supports the creation of objects and their associated data sets and procedures). Finally, actual implementation and object creation of this system is accomplished.
Homeostasis and compensation: the role of species and resources in ecosystem stability

A synthesis of community and ecosystem ecology should yield insights into the role of species in ecosystem function. Concepts from these subdisciplines of ecology, specifically species compensation and ecosystem homeostasis, can be linked by analyzing the effect of changes in the abundance of species on ecosystem processes. Compensatory changes in species populations in response to environmental fluctuations can maintain an approximate steady state between rates of resource supply and resource consumption. We predict that ecosystem-level properties, such as species richness, total population, biomass, and energy use, will exhibit less variability in response to environmental change than will species composition. We tested this prediction using long-term data of a desert rodent community responding to natural environmental fluctuations and of a plant community responding to experimental manipulations. For the rodents, species composition was twice as variable as the ecosystem properties. This result was the same for both the analysis of variability around the 22-yr average and the analysis of variability from one time period to the next. For the plant communities, species composition was more variable among treatments in most years than stem count or species richness. Using the variance ratio proposed by J. L. Klug et al. we detected negative covariances in the rodent community, confirming the presence of compensatory dynamics.
Dynamic Optimization in a Discontinuous World

Many engineering tasks can be formulated as dynamic optimization or open-loop optimal control problems, where we search a priori for the input profiles to a dynamic system that optimize a given performance measure over a certain time period. Further, many systems of interest in the chemical processing industries experience significant discontinuities during transients of interest in process design and operation. This paper discusses three classes of dynamic optimization problems with discontinuities: path-constrained problems, hybrid discrete/continuous problems, and mixed-integer dynamic optimization problems. In particular, progress toward a general numerical technology for the solution of large-scale discontinuous dynamic optimization problems is discussed.
Clarification on the detection of epoetin delta and epoetin omega using isoelectric focusing.

To the Editor: In a recent article in your journal, Delanghe et al. [1]. reviewed both the indirect and direct methods for the detection of recombinant human erythropoietin (rhEPO) in doping analysis. However, some of the statements made are incorrect and some others deserve clarification. The direct detection of the misuse of rhEPO and analogues in sports is currently done in World Antidoping Agency (WADA) accredited laboratories following the method developed by Lasne [2], which is based on the differences in the isoelectric focusing (IEF) behavior between endogenously produced urinary EPO (uEPO) and the recombinant products (epoetin alpha, beta, etc.) and analogues (i.e., darbepoetin alpha). Those differences are claimed to reside in the glycans of those glycoproteins, resulting from the enzymatic endowment of the particular cell in which the protein is expressed as well as from the selective purification applied to obtain each pharmaceutical product. The article, however, is wrong in stating that epoetin omega is produced in human cells. Epoetin omega is produced in Baby Hamster Kidney (BHK) cells [3]. Its glycosylation profile is monitored using the same IEF method and it is perfectly distinguishable from endogenous EPO (Fig. 1). Epoetin delta (Dynepo, Shire Pharmaceuticals) is expressed in human cells, although it
Mapping using gene encyclopaedias.

Overlap cloning and large fragment electrophoresis bring total knowledge of the E. coli genome into prospect.
Activity recognition with smartphone sensors

The ubiquity of smartphones together with their ever-growing computing, networking, and sensing powers have been changing the landscape of people's daily life. Among others, activity recoginition, which takes the raw sensor reading as inputs and predicts a user's motion activity, has become an active research area in recent years. It is the core building block in many high-impact applications, ranging from health and fitness monitoring, personal biometric signature, urban computing, assistive technology, and elder-care, to indoor localization and navigation, etc. This paper presents a comprehensive survey of the recent advances in activity recognition with smartphones' sensors. We start with the basic concepts such as sensors, activity types, etc. We review the core data mining techniques behind the main stream activity recognition algorithms, analyze their major challenges, and introduce a variety of real applications enabled by activity recognition.
Nonlocal dispersion in porous media: Nonmechanical effects

Abstract Nonmechanical dispersion mechanisms at high Peclet number in porous media give rise to persistent transients that cannot be predicted by a local Fickian macrotransport equation. Instead, a nonlocal macrotransport equation is derived, which relates the average mass flux to a convolution integral in space and time between the average concentration gradient and a spatial- and temporal-wavelength-dependent effective diffusivity. The nonlocal diffusivity is derived from the fundamental microstructural transport processes. The transient effects arising due to stagnant and recirculating regions in the medium and due to a diffusive boundary layer near solid surfaces are shown to affect the residence-time distribution (RTD) of media whose overall length to microscale size ratio L/a is not large compared to Pe and Pe 1/3 , respectively. Here, the Peclet number, Pe = Ua/D , is based on the average velocity through the medium U , the microstructural length scale a and the molecular diffusivity D in the medium. The nonlocal dispersion theory allows a calculation of the full form of the RTDs, which may be bimodal and generally exhibit long-time tails in media of short to moderate length. Experimental measurements of transient dispersion in consolidated media are shown to be in agreement with the theoretical prediction of dispersion due to the diffusive boundary layers near solid surfaces.
William Osler, Sigmund Freud and the evolution of ideas concerning cerebral palsy.

(1993). William Osier, Sigmund Freud and the evolution of ideas concerning cerebral palsy. Journal of the History of the Neurosciences: Vol. 2, No. 4, pp. 255-282.
UWTC LUTE: technology in harmony with human performance

In the nearly 20 years of the existence of the UWTC Laboratory for Usability Testing and Evaluation (LUTE), our overriding goal has been to put people first in product design. In working toward this goal, we have always faced the same four challenges: to educate students through practice, change how companies and organizations design products, advance the state of the art in usability research, and stay at the cutting edge. This talk will take a brief tour of LUTE's efforts to meet this goal and address these challenges, with snapshots of typical projects and the people who worked on them; will mention some of the current work under way in the lab; and will close with some thoughts about LUTE's future and how it might articulate with that of our field.
Differential polarimetric fiber-optic sensor configuration with dual wavelength operation

Presentation d'un capteur polarimetrique differentiel a fibre optique. Etude de son fonctionnement en tant que capteur de temperature
Theoretical hydraulic consequences of vein graft taper.

Abstract Objective Internal diameter is a strong predictor of patency of infrainguinal vein grafts. However, most vein grafts are tapered, with variable diameter along their length. It is unknown which diameter is most important in determining graft resistive properties, that is, its mean diameter, minimum diameter, or some geometric combination thereof. The purpose of this analysis was to examine the hydraulic consequences of vein graft tapering, with longitudinal impedance (Z L ), a conduit-specific measure of pulsatile resistance along straight rigid tubes. Methods Proximal and distal graft pressure, pressure gradient (ΔP), and blood flow (Q) were measured intraoperatively in a 100 cm bypass graft and digitally recorded for 10 seconds at 200 Hz. With the Womersley solution for fully developed fluid flow in a rigid tube, a series of ΔP waveforms were generated for graft diameters ranging from 1.2 to 8.2 mm. With an axisymmetric form of the Navier-Stokes equations, a second series of ΔP waveforms were computed for grafts with long smooth symmetric tapers ranging from 0% to 90%, with geometric mean diameter of 3.2, 4.2, and 5.2 mm (%Taper = 100 × [proximal diameter − distal diameter]/proximal diameter). For each set of ΔP and Q, Z L was calculated as ΔP/Q, plotted over a range of 8 Hz, and integrated over 4 Hz to yield ∫Z L . Results The architecture of the calculated ΔP and Z L waveforms closely approximated their measured counterparts, validating the method. As expected, Z L was highly diameter-dependent in a nonlinear fashion. With a clinically relevant boundary of less than 50 × 10 3 dyne/cm 5 as "acceptable," the minimum acceptable diameter of nontapered 100 cm bypass conduits was 4.3 mm. Analysis of graft taper revealed that small amounts of taper in large conduits were well-tolerated. For example, introduction of 32% taper in a 5.2 mm graft (6.2 mm → 4.2 mm) caused only an 8% increase in ∫Z L (from 32 to 35 × 10 3 dyne/cm 5 ). More pronounced taper in smaller conduits rendered them unacceptable. For example, 53% taper of a 4.2 mm graft (5.7 mm → 2.7 mm) created a conduit with ∫Z L of 70 × 10 3 dyne/cm 5 , well above the acceptable limit. The relationship between Z L and percent taper was nonlinear and strongly dependent on mean diameter. Conclusions The relationship between Z L and diameter in vein grafts is nonlinear; thus Z L increases rapidly in conduits smaller than 4 mm. Tapered vein grafts behave hydraulically like nontapered grafts, provided their geometric mean is greater than 4 mm and their degree of taper is less than 40%. Tapered veins are satisfactory conduits for long-segment bypass grafts, provided their mean diameter is acceptable.
Renormalization-group analysis of supersymmetric mass hierarchies

Abstract A renormalization-group analysis is performed for supersymmetric models of the O'Raifeartaigh type coupled to a Yang-Mills supermultiplet. For an appropriate range of coupling constants, we find that large mass ratios can be naturally generated by one-loop corrections to the effective potential. The results confirm Witten's recent observation that these models provide a potential solution to the gauge hierarchy problem. The general renormalization-group analysis of symmetry breaking developed in this paper is applicable in contexts other than supersymmetry. We also give a simple argument that the canonical form of the supersymmetric Ward identities can be maintained in the presence of quantum effects.
Document skew-angle detection algorithm

As part of research into document image processing, an algorithm has been developed to detect the degree of skew in a scanned binary image. The principal components of the algorithm are component labelling, a procedure to reduce the amount of data to be processed, a technique to minimize the effect of non-textual data (graphics, forms, line art, large fonts, and dithered images) on the measurement of skew angle, and the Hough transform. The performance of the algorithm has been evaluated using a sample size of several hundred images of medical journal pages. Evaluation shows that a skew angle may be detected with an accuracy of about 0.50 degree.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Endoscopic correction of vesicoureteral reflux in children using autologous chondrocytes: preliminary results.

AbstractPurpose: Previous approaches to the endoscopic correction of vesicoureteral reflux have used foreign bulking substances, raising concern regarding safety and long-term efficacy. We describe the results of a clinical trial using transurethral injection of autologous chondrocytes to correct vesicoureteral reflux in children.Materials and Methods: A total of 29 children (46 ureters) with grades II to IV vesicoureteral reflux were treated at 2 sites. Each child underwent cystoscopy and ear cartilage biopsy at the initial setting. Chondrocytes were grown in culture for 6 weeks. Patients then returned for transurethral injection of chondrocytes into the bladder trigone to correct reflux. Ultrasound was performed 1 month and radionuclide cystography was done 3 months postoperatively to confirm reflux resolution. When reflux persisted, repeat treatment with stored chondrocytes was offered.Results: Initial chondrocyte injection corrected reflux in 26 of the 46 ureters (57%), while secondary injection was s...
Model predictions of the extent of heterogeneous coal combustion during rapid evolution of volatiles

Abstract Two relatively simple, single-particle coal combustion models are developed and used to predict the extent of heterogeneous combustion during rapid devolatilization. The first model uses the flame sheet approximation while the second employs finite gas-phase reaction rates. Both models predict that small particles ( μm diameter) burn heterogeneously and large particles (> 100 μm diameter) burn homogeneously, but heterogeneous mass loss is severely underestimated by the simpler flame-sheet model in comparison to the more realistic finite-rate-chemistry model for intermediate sized particles typical of a utility grind. Small particle size, high oxygen concentration and low devolatilization rate, in that order of importance, yield more extensive heterogeneous combustion, while temperature, volatiles composition, gas-phase kinetics, and surface reaction rates have negligible impact.
Growth reduction by dietary tannins: Different effects due to different tannins

Abstract The effects of different tannins were compared in feeding trials utilizing rats fed diets that were equal in their total phenolics content. The drug propranolol was used to suppress proline-rich salivary protein production in some animals in order to examine the defensive potential of these proteins against dietary tannins. Differences were evident in the way different tannins affected digestion and the post-digestive assimilation of nutrients into new body mass. Different tannins also interacted differently with propranolol and were recovered in fecal material in different quantities. While the two condensed tannin-containing diets and one hydrolysable tannin-containing diet each had similar effects on overall weight gain, they appeared to cause their effects in different ways. These results are discussed in the context of the frequently made assumption that all tannins act as feeding deterrent allelochemicals in a uniform manner.
Concentration and form of dissolved sulfide in the oxic water column of the ocean

During May through July 1987, we analyzed for hydrogen sulfide in the oxic water column of the eastern Mediterranean Sea (May–June) and the northwest Atlantic Ocean (July). Cathodic stripping square wave voltammetry was used to detect and quantify sulfide species. This is a direct method requiring no sample preparation. Our measurements show a consistent profile of 2 nM in the Mediterranean Sea, except for increases that occur at the oxygen maximum in the photic zone and above the hypersaline anoxic brine of the Bannock Basin (2.9 mM sulfide maximum). The measurements in the Atlantic Ocean are lower and more variable as a result of different source waters. Sulfide increases are noted near the surface and in cold pool waters along the East Coast of the United States. Experimental manipulation of seawater samples suggests that the sulfide is bound covalently to a metal. The metal (s) is likely to have an electron configuration consistent with inert complexes, which do not dissociate readily to form free sulfide. Free sulfide reacts with iodate and oxygen in seawater. Sulfide in an inert metal complex should not dissociate and react with iodate and oxygen readily. We propose that the kinetic stability of sulfide-metal complexes is the primary control on the distribution and reactivity of sulfide in the oxic water column of the ocean, rather than thermodynamic considerations alone. This kinetic effect results from high ligand field stabilization energies associated with the electron configuration of the metal (e.g. d3 and d6 low spin octahedral metal complexes).
Generalized instrumental variables estimation of autoregressive conditional heteroskedastic models

Abstract This paper considers an alternative to maximum likelihood (ML) estimation of the autoregressive conditional heteroskedastic (ARCH) model introduced in Engle (1982). Specifically, the analysis demonstrates that Hansen's (1982) generalized method of moments (GMM) procedure can be applied for estimation of ARCH models. As an illustration, we compare the results from ML estimation and GMM estimation of Engle and Kraft's (1983) ARCH model of U.S. inflation.
Ionisation Phenomena in Active Nitrogen

IN some recent experiments with active nitrogen, it has been found that ionisation effects differ with the gases mixed with the nitrogen. When the active nitrogen alone was drawn past an ion trap into cylindrical condensers, the negative charges obtained were found to be proportional to the areas of the negative electrodes, indicating that the conductivity is due to photo-electrons emitted from the electrode and not to the production of free ions in the gas. The same observations were made when hydrogen and mercury were added to the active nitrogen before it entered the condenser. With iodine (ionisation potential 9.4 volts), however, a different ratio of currents was obtained, showing that ionisation is produced in the gas.
Phosphorylation of the cAMP Response Element Binding Protein CREB by cAMP-Dependent Protein Kinase A and Glycogen Synthase Kinase-3 Alters DNA-Binding Affinity, Conformation, and Increases Net Charge

The cAMP response element binding protein CREB activates the transcription of genes in response to phosphorylation by cAMP-dependent protein kinase A (PKA) and other protein kinases. Phosphorylated...
Antireflection surface structure: dielectric layer(s) over a high spatial-frequency surface-relief grating on a lossy substrate

With proper design, a dielectric (or lossy) overcoated high spatial-frequency rectangular-groove grating on a lossy substrate can exhibit zero reflectivity. A procedure for designing these structures based on impedance matching and the effective index of the grating in the long wavelength limit is presented. The needed filling factor and groove depth of the grating to produce antireflection behavior are calculated for a given complex index of refraction of the substrate and index and thickness of the coating layer. The analysis is applicable to any wavelength and angle of incidence and for either TE or TM polarization. It is shown that multiple zeroreflectivity solutions occur. Necessary and sufficient conditions for zero-reflectivity solutions are derived in the appropriate parameter space. The analysis is also extended to multiple dielectric (or lossy) overlayers. Since the treatment is based on the equivalence of the grating to a lossy layer in the long wavelength limit, the treatment also includes as an intermediate step the design of a dielectric (or lossy) overcoated homogeneous lossy layer on a lossy substrate. The designs of zero-reflectivity gold gratings overcoated by a single dielectric layer are presented for wavelengths in the 0.44-12.0-microm range. The sensitivity of these resulting structures to changes in the angle of incidence, the coating thickness, the coating index, the filling factor, and the groove depth are presented. Furthermore, the design of dielectric overcoated gold gratings that are simultaneously antireflecting for both TE and TM polarizations is presented.
On the Utility of Frequency Reuse in Cognitive Radio Channels

We consider the generalized cognitive radio channel where the secondary user is allowed to reuse the frequency during the active periods of the primary user, as long as the primary rate remains the same. In this setting, the optimal power allocation policy with a single antenna secondary transmitter (and receiver) is explored. Interestingly, we show that the offered gain resulting from the frequency reuse during the active periods of the spectrum disappears in both the low and high signal-to- noise ratio (SNR) regimes. This drawback, however, is shown to disappear with multi-antenna nodes by using simple zero-forcing strategies at both ends of the secondary channel.
A microfabricated scaffold for retinal progenitor cell grafting

Diseases that cause photoreceptor cell degeneration afflict millions of people, yet no restorative treatment exists for these blinding disorders. Replacement of photoreceptors using retinal progenitor cells (RPCs) represents a promising therapy for the treatment of retinal degeneration. Previous studies have demonstrated the ability of polymer scaffolds to increase significantly both the survival and differentiation of RPCs. We report the microfabrication of a poly(glycerol-sebacate) scaffold with superior mechanical properties for the delivery of RPCs to the subretinal space. Using a replica molding technique, a porous poly(glycerol-sebacate) scaffold with a thickness of 45 μm was fabricated. Evaluation of the mechanical properties of this scaffold showed that the Young’s modulus is about 5-fold lower and the maximum elongation at failure is about 10-fold higher than the previously reported RPC scaffolds. RPCs strongly adhered to the poly(glycerol-sebacate) scaffold, and endogenous fluorescence nearly doubled over a 2 day period before leveling off after 3 days. Immunohistochemistry revealed that cells grown on the scaffold for 7 days expressed a mixture of immature and mature markers, suggesting a tendency towards differentiation. We conclude that microfabricated poly(glycerol-sebacate) exhibits a number of novel properties for use as a scaffold for RPC delivery.
The pediatric test of brain injury: Development and interpretation

The Pediatric Test of Brain Injury (PTBI) is designed to assess neurocognitive, language, and literacy abilities that are relevant to the school curriculum of children and adolescents recovering from brain injury. The PTBI is intended to help clinicians establish baseline levels of cognitive–linguistic abilities in the acute stages of recovery, identify strengths and weaknesses for informing intervention, monitor functional changes and track recovery patterns, and guide decision making related to school reintegration and educational performance. This article describes the research version of the PTBI with regard to theoretical concerns guiding its development, selection of neurocognitive and language abilities that are relevant to the school curriculum and likely to be affected by brain injury, the rationale for tracking early recovery, and research being conducted on the PTBI to establish criterion-referenced benchmarks for children and adolescents from age 6 through 16 years. Two case examples illustrate qualitative interpretations of results on each of the PTBI subtests, which are discussed with regard to implications for further curriculum-based language assessment and successful reintegration into school.
The Sendai Virus C Protein Binds the L Polymerase Protein to Inhibit Viral RNA Synthesis

The Sendai virus nested set of C proteins which are expressed in an alternative open reading frame from the P mRNA has been shown to downregulate viral RNA synthesis. Utilizing a glutathioneS-transferase (gst) C fusion protein (gstC), we have shown that C protein forms a complex with the L, but not the P, subunit of the viral RNA polymerase. When P, L, and gstC are coexpressed, an oligomer of P, through its interaction with L, is also bound to beads. Since binding of C to L in the P-L complex does not disrupt P binding, the C and P binding sites appear to be different. GstC binding to L occurs only when the proteins are coexpressed in the same cell. The gstC, but not gst, protein inhibits viral transcriptionin vitro,showing that the fusion protein retains biological function. Pulse–chase experiments of the various complexes show that L protein synthesized alone has a half-life of 1.2 hr, which is increased 12.5-fold by binding P, but is not significantly increased by binding gstC. Analyses of complex formation with truncations of L protein show that the C-terminal 1333 amino acids of L are not required for binding C. The dose–response curves show that replication of the genomic DI-H RNA is more sensitive to inhibition by C protein than is the synthesis of DI leader RNA, suggesting that the downregulation of RNA synthesis may be more complex than just the inhibition of the initiation of RNA synthesis.
Interleg coordination in quiet standing: influence of age and visual environment on noise and stability.

ABSTRACT The authors reexamined reported effects of age, illumination, and stationary visible structure on the net center of pressure (COP) derived from dual, side-by-side force plates (J. Kinsella-Shaw, S. Harrison, C. Colon-Semenza, & M. Turvey, 2006) from the perspective of axial postural control. They questioned how left and right COP x (t), COP y (t), and vertically oriented ground reactive force, GRF z (t), coordinated during quiet standing. The Cross- recurrence Quantification (CRQ) revealed that coordination was primarily between fluctuations of similar direction, with coordination of left and right COP y (t) (anteroposterior fluctuations) dominant. CRQ also revealed that (a) illumination and structure affected the interlimb dynamics of older (M age = 72.2 ± 4.90 years) participants more than their younger (M age = 22.8 ± 0.83 years) counterparts, and (b) older participants exhibited greater interlimb entrainment (dynamical stability) in the presence of greater interlimb noise.
Selective area growth of GaP on Si by MOCVD

Abstract Single crystals of GaP were grown on 4° miscut (100) Si substrates by selective area metalorganic chemical vapor deposition. Silicon nitride patterns were used to mask the wafer; no GaP nucleated on the silicon nitride patterns. The top and side walls of the selectively grown GaP stripes (3 μm width) seem to be the (100) and (111) crystal planes. Cross-sectional TEM analysis revealed a smooth GaPSi interface. Focused Raman spectroscopy with a spatial resolution of ∼ 1 μ m was used to assess the crystal quality of individual GaP mesas.