cssi/SciSciGPT-SciSciNet huggingface dataset:
Identification and estimation of dynamic models with a time series of repeated cross-sections

Abstract Repeated cross-sectional data contain information on independent cross-sections of individual units at two or more points in time. Estimation of dynamic models with such data is made difficult by the general lack of information on lagged dependent and independent variables and the consequent unobservability of the intertemporal covariances needed to identify and estimate dynamic models. It is demonstrated here that the parameters of such models, both linear and nonlinear, both with and without fixed individual effects, are identified and can be consistently estimated with the imposition of certain restrictions. The paper includes an examination of the identification and estimation with repeated cross-sectional data of dynamic discrete dependent variable models, which can be parameterized in terms of transition rates between the different cross-sections.
Interactions of Arsenate with the Phosphate-Transporting System of Yeast

Arsenate competes with phosphate for transport into the yeast cell. The affinity of the two substances for the transport system is about equal, but in mixtures the phosphate is taken up about twice as fast as arsenate, because the maximal transport rate for phosphate is about twice as high. In addition to the competitive effect, arsenate causes a continuous and irreversible inactivation of the transport system that can be characterized by first order kinetics. The rate of arsenate inactivation is slower in the presence of phosphate and the amount of arsenate taken up before complete block is established is also decreased. The inactivation of the transport system cannot be relieved by washing or by treatment with glucose and phosphate. The inactivation is not the result of an inhibition of metabolism.
Pseudopseudohypoparathyroidism with spinal cord compression

We describe a patient with pseudopseudohypoparathyroidism who had an osseous tubercle on the anterolateral margin of the foramen magnum causing compression of the spinal cord. This patient had no evidence for any endocrinopathies and had no other spinal canal anomalies. We suggest that the morphologic phenotype found in patients with pseudopseudohypoparathyroidism, also known as Albright's hereditary osteodystrophy, has an associated risk for spinal cord compression due to congenital vertebral anomalies. The poor recovery of neurologic function following spinal decompression mandates prompt recognition and therapy of this condition in patients with Albright's hereditary osteodystrophy.
Experimental study of local strong parity violation in relativistic nuclear collisions

Abstract Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created in relativistic heavy ions collisions. These domains are predicted to lead to charge separation along the system orbital momentum of the system created in non-central collisions. Three-particle mixed harmonics azimuthal correlator is a P even observable but directly sensitive to the charge separation effect. Using this observable to analyze Au+Au and Cu+Cu collisions at s N N = 200 and 62 GeV, STAR detects a signal consistent with several of the theoretical expectations. Possible contributions from effects not related to parity violation are studied with existing event generators, which fail to describe the data. Future directions in studying the effect are discussed.
The effect of fluid shear stress upon cell adhesion to fibronectin‐treated surfaces

Cell attachment to and spreading upon a surface is mediated by adhesion molecules, such as fibronectin. The role of fibronectin in maintaining cell adhesion was examined by measuring cell attachment following exposure of cells to laminar flow in a parallel-plate flow channel. 3T3 fibroblasts were allowed to adhere to glass slides with or without preadsorbed fibronectin for 2 h before exposure to shear stresses ranging from 5 to 140 dyne/cm2. For cells which adhered to glass surfaces, cell loss was biphasic with a significant loss of cells during the first 2 min of flow, followed by a much slower decline in the number of attached cells with time. Following exposure to shear stresses greater than 5 dyne/cm2, the number of attached cells decreased exponentially as the shear stress increased. The distribution of adhesive stresses among the population of cells was log-normal with a median of 50 dyne/cm2, a mean of 82 dyne/cm2 and a standard deviation of 108 dyne/cm2. After exposure to flow for 2 h, the adhesive stress of the remaining cells decreased to a mean value of 50 dyne/cm2. Cell adhesion after exposure to flow was increased by preadsorbing fibronectin to the glass surface. The initial loss of cells from fibronectin-treated glass following exposure to flow correlated with the degree of cell spreading. Preadsorbed fibronectin resulted in a greater number of bonds between the surface and the cell, which in turn promoted cell spreading and increased the adhesive strength of the cell.
Degree of polymerization of deoxyribonucleic acid.

THE improvement of methods for isolating cell nuclei requires the establishment of suitable criteria of nuclear intactness which may be used to evaluate changes in technique1. The following experiments were performed in the course of an effort to devise methods for following changes in the degree of polymerization of deoxyribonucleic acid during nuclear isolation.
Root fasciation in the irish potato (solanum tuberosum)

The root systems of 175 Triumph, 50 Progress and 4 Red Warba potato plants were carefully scrutinized in order to detect root fasciation. Only 6 plants showed root fasciations and all of these were of the double type, involving only two roots. Forty-two plants with fasciated stems produced a single example of fasciated roots on each of three plants. Of the 187 non-fasciated plants only three showed fasciated roots and one of these could be traced back a generation to a fasciated parent plant.
College Women Miss the Mark When Estimating the Impact of Full-Time Maternal Employment on Children’s Achievement and Behavior

The goals of the current study were to apply the construct of stereotype accuracy to the domain of college women’s perceptions of the effects of full-time maternal employment on children. Both accuracy/inaccuracy and positive/negative direction were examined. Participants were 1,259 college women who provided stereotyped projections about the effects of full-time employment on children’s IQ scores, formal achievement tests, school grades, and internalizing and externalizing behavior problems. Their stereotype effect sizes were compared to meta-analytic effect sizes used to estimate the “actual” effects of maternal employment on children. Individual differences in these stereotypes were also examined. Results indicate that, on average, college women overestimated the negative effects of full-time maternal employment on child outcomes, especially behavior problems. Significant variability in the direction and accuracy of the stereotypes was explained by individual characteristics such as gender ideology, ex...
Foreword to volume two

The IEEE Antennas and Wireless Propagation Letters (LAWP) is an archival journal devoted to the rapid publication of new theoretical and experimental results in all areas of interest to the IEEE Antennas and Propagation Society, such as antennas and arrays, wireless propagation, scattering, electromagnetic theory, electronic properties of materials, high- and low-frequency methods, numerical techniques in electromagnetic boundary-value problems, measurements, and standards. Application papers of particular interest to industry, as well as contributions containing novel ideas, are encouraged.
Islet Cell Carcinoma of the Pancreas

n = 11) followed by glucagonoma ( n = 6) and insulinoma ( n = 4) were the most common functioning tumors. In the patients undergoing a laboratory study, 67% of the nonfunctioning tumors had elevated peptide hormone levels. Potentially curative resections were performed in 17 patients (26%), palliative procedures in 35 (55%), and exploratory laparotomy alone in 12 (19%). One patient (2%) died within 30 days after operation. Symptomatic improvement was achieved in 96% of patients with a mean duration of 22 months. Three- and five-year survivals were 66% and 49%, respectively. In patients with curative resection, the disease-free survival at 3 years was 53% (95% CI: 32–86%). The presence of diffuse hepatic metastases was a predictor of poor survival at 3 years (74% versus 58%; p = 0.05); there was no statistically significant difference in survival between functioning and nonfunctioning groups ( p > 0.1). Although curative resection for ICC is rare, meaningful palliation can be achieved in most patients with rare mortality and acceptable morbidity.
A mini-residency program in orthognathic surgery

A method of teaching major orthognathic surgical techniques is presented. One hundred hours of instruction in laboratory, practical, clinical, and operating room experiences were presented over two months, on alternate weekends. These intervals allowed for assimilation of new didactic material, readings, and study and laboratory exercises at home. Four teams of three oral and maxillofacial surgeons rotated to the operating rooms during each weekend session to experience hands-on training. The protracted period of follow-up observations enabled participants to witness most cases from start to finish and learn to anticipate and manage sequellae. Experienced oral and maxillofacial surgeons demonstrated a quick grasp of newer techniques of orthognathic surgery, and most translated the mini-residency experience into their practices.
What Drives Publishing Productivity for Pretenure Marketing Faculty: Insights Using the Lens of Resource Advantage Theory

The promotion, tenure and salary of marketing faculty have been topics of intense interest recently. What has received less interest are the drivers of publishing productivity, especially for new, pre-tenure faculty. We use resource-advantage (RA) theory to examine the drivers of pre-tenure faculty productivity, specifically in the top marketing journals. Positive predictors of productivity, and thus key faculty resources are: degree-granting department ranking, advisor productivity and length of time in the new job. As would be predicted by RA theory, number of methods courses in a doctoral program has no effect on publishing.
Future of toxicology--predictive toxicology: An expanded view of "chemical toxicity".

A chemistry approach to predictive toxicology relies on structure−activity relationship (SAR) modeling to predict biological activity from chemical structure. Such approaches have proven capabilities when applied to well-defined toxicity end points or regions of chemical space. These approaches are less well-suited, however, to the challenges of global toxicity prediction, i.e., to predicting the potential toxicity of structurally diverse chemicals across a wide range of end points of regulatory and pharmaceutical concern. New approaches that have the potential to significantly improve capabilities in predictive toxicology are elaborating the “activity” portion of the SAR paradigm. Recent advances in two areas of endeavor are particularly promising. Toxicity data informatics relies on standardized data schema, developed for particular areas of toxicological study, to facilitate data integration and enable relational exploration and mining of data across both historical and new areas of toxicological inves...
A SPECTRAL MEASUREMENT OF THE CYCLICAL PATTERNS OF MULTIVARIATE TIME SERIES

Although the diffusion and transmission of cyclical impulses are basic characteristics of economic and business activities, traditional studies of business cycles do not provide an effective measure of cyclical interaction. The purpose of this paper is to use spectral analysis to determine the cyclical patterns of multivariate economic and business time series. The proposed methodology was applied to the regional industrial diversification problem.
Surface tension, roughening, and lower critical dimension in the random-field Ising model

A continuum interface model is constructed to study the low-temperature properties of domain walls in the random-field Ising model (RFIM). The width of the domain wall and its surface tension are computed by three methods: Simple energy accounting, dimensional arguments, and approximate renormalization-group calculations. All methods yield a surface tension which is positive at sufficiently low temperature for small random fields, $h$, provided that the dimensionality $dg2$. The lower critical dimension of the RFIM is thus argued to be 2. While effects due to discreteness of a lattice are argued to alter some of the continuum results quantitatively, they do not change these central conclusions. For $dl2$ the ferromagnetic correlation length of the RFIM behaves like ${h}^{\ensuremath{-}2{(2\ensuremath{-}d)}^{\ensuremath{-}1}}$ as $h\ensuremath{\rightarrow}0$.
Rifle Marksmanship with Three types of Combat Clothing

Soldier performance on simple visual, auditory, and psychomotor tasks has been shown to be impaired by the bulkiness of combat clothing. Since rifle marksmanship is a complex task requiring the coordination of simple sensory and psychomotor skills, it was hypothesized that bulky combat clothing would also impair this task which is so critical to successful soldier performance and survival. Each of 30 male soldier volunteers, matched on rifle marksmanship ability, was assigned to one of three clothing conditions of increasing bulk: battle dress uniform, fighting load, or MOPP-IV chemical protective clothing. After four days of practice on the Weaponeer M16 rifle simulator, soldiers were assessed on marksmanship for pop-up targets (in both rifle supported and unsupported conditions) while dressed in the respective combat clothing. Results of a 3 × 2 (clothing × rifle support) analysis of variance showed that (a) regardless of clothing condition, marksmanship was significantly better when the rifle was suppo...
Polarisation-independent tunable bandpass filter utilising symmetric branch beam splitters

A two-port polarisation-independent electro-optically tunable bandpass filter in Ti:LiNbO/sub 3/ in the 1535 nm wavelength regime using strain-induced polarisation conversion with a tuning rate of 0.082 nm/V and a tuning range of 13 nm is reported.
Serine/threonine protein kinases synergistically regulate phospholipase D1 and 2 and secretion in RBL-2H3 mast cells

Abstract The role of phospholipase (PL) D in secretion was examined in RBL-2H3 mast cells which contain both PLD1 and 2. The effects of pharmacologic stimulants and inhibitors of Ca 2+ /calmodulin-dependent kinase II, protein kinase C, and protein kinase A suggested that all three kinases synergistically stimulate PLD and, when associated with a calcium signal, secretion as well to indicate a possible linkage between these two events. Overexpression of either PLD1 or 2 markedly enhanced the activation of PLD by pharmacologic stimulants as well as antigen and both isoforms thus appear co-ordinately regulated. As the expressed PLD1 was associated with secretory granules and PLD2 with the plasma membrane, the two isoforms may serve distinct but complementary functions in secretion.
Disparity in Physical Activity Among Urban Youth: An Ecologically Guided Assessment

BackgroundInsufficient physical activity among urban youth increases risk of chronic disease.PurposeThis study assessed reported physical activity to determine when disparities in participation emerge and what ecologically guided factors are linked with high activity.MethodsWe administered a cross-sectional survey to a diverse sample of 321 fourth-, sixth-, and eighth-graders measuring physical activity and a range of ecologically guided variables via self-report. Students who reported high versus low levels of physical activity were compared in bivariate and stepwise regression models stratified by gender and grade to elucidate factors associated with high physical activity.ResultsThe proportion of highly active students declined between fourth and sixth/eighth grade, driven largely by a decline in highly active girls. Unique factors were associated with high physical activity by grade or gender including self-efficacy among fourth-graders (adjusted odds ratio [aOR] = 14.51, 95% confidence interval [CI],...
Application of preconditioned GMRES to the numerical solution of the neutron transport equation

The generalized minimal residual (GMRES) method with right preconditioning is examined as an alternative to both standard and accelerated transport sweeps for the iterative solution of the diamond differenced discrete ordinates neutron transport equation. Incomplete factorization (ILU) type preconditioners are used to determine their effectiveness in accelerating GMRES for this application. ILU(τ), which requires the specification of a dropping criteria τ, proves to be a good choice for the types of problems examined in this paper. The combination of ILU(τ) and GMRES is compared with both DSA and unaccelerated transport sweeps for several model problems. It is found that the computational workload of the ILU(τ)-GMRES combination scales nonlinearly with the number of energy groups and quadrature order, making this technique most effective for problems with a small number of groups and discrete ordinates. However, the cost of preconditioner construction can be amortized over several calculations with different source and/or boundary values. Preconditioners built upon standard transport sweep algorithms are also evaluated as to their effectiveness in accelerating the convergence of GMRES. These preconditioners show better scaling with such problem parameters as the scattering ratio, the number of discrete ordinates, and the number of spatial meshes. These sweeps based preconditioners can also be cast in a matrix free form that greatly reduces storage requirements.
Simulation of offshore wind turbine response for long-term extreme load prediction

When there is interest in estimating long-term extreme loads for an offshore wind turbine using simulation, statistical extrapolation is the method of choice. While the method itself is rather well-established, simulation effort can be intractable if uncertainty in predicted extreme loads and efficiency in the selected extrapolation procedure are not specifically addressed. Our aim in this study is to address these questions in predicting blade and tower extreme loads based on stochastic response simulations of a 5 MW offshore turbine. We illustrate the use of the peak-over-threshold method to predict long-term extreme loads. To derive these long-term loads, we employ an efficient inverse reliability approach which is shown to predict reasonably accurate long-term loads when compared to the more expensive direct integration of conditional load distributions for different environmental (wind and wave) conditions. Fundamental to the inverse reliability approach is the issue of whether turbine response variability conditional on environmental conditions is modeled in detail or whether only gross conditional statistics of this conditional response are included. We derive long-term loads for both these cases, and demonstrate that careful inclusion of response variability not only greatly influences such long-term load predictions but it also identifies different environmental conditions that bring about these long-term loads compared with when response variability is only approximately modeled. As we shall see, for this turbine, a major source of response variability for both the blade and tower arises from blade pitch control actions due to which a large number of simulations are required to obtain stable distribution tails for the turbine loads studied.
Disc Biomechanical Response due to Incomplete Length of Collagen Fibers in Various Regions of Annulus Fibrosus: A Finite Element Investigation

Collagen fibers in the annulus fibrosus (AF) play a significant role in maintaining the disc mechanical behavior. In healthy discs, AF fibers are concentrically arranged in a zigzag fashion. Tensile loads are transmitted to these fibers when the disc is loaded in compression. As a result, disc bulging occurs. Initiation and progression of mild cervical disc degeneration (DD) has been the subject of clinical concern [1]. The mild DD is associated with structural interruption in laminar organization of fibers in partial AF regions and incomplete length of fibers is a major form of structural interruption in AF fibers [2]. Moreover, a loss of lamellar fiber structure contributes to the progression of spinal deformity [3]. Past research have documented the biomechanical role of complete length of fibers in governing a healthy disc behavior [4]; however, there is a lack of clear understanding as to how incomplete length of fibers in different AF regions affect overall disc biomechanics and how they may play a role in initiating the propagation of DD. The focus of the current study is to investigate the disc biomechanical response due to incomplete length of fibers in outer, middle, and inner AF regions.Copyright © 2010 by ASME
Adenocarcinoma of the esophagus in the young.

Practitioners have noted a striking increase in the number of young patients under the age of 40 years old who develop esophageal adenocarcinoma. The aim of this study was to characterize the presentation, pathology and therapeutic outcome of these young patients. The records of patients who presented to the Foregut Surgical Service at the University of Southern California with esophageal adenocarcinoma between 2000 and 2007 were retrospectively reviewed. The presentation, tumor stage and histology, therapy and outcome of the patients under the age of 40 were compared to those ≥40. Of the 374 patients reviewed, 20 (5 %) were under the age of 40. There were two patients in their second and 18 in their third decade of life. The youngest patient was 25 years old. A history of gastroesophageal reflux disease or Barrett’s esophagus was less common in patients <40 than in those ≥40; 15 and 5 % compared to 61 and 46 %. Similarly, patients <40 had a significantly longer time interval between the onset of symptoms and the diagnosis of their cancer than those ≥40; 4.5 vs. 2 months, p = 0.04. They also had a higher prevalence of stage IV disease (30 vs. 6 %, p = 0.0003), a shorter time to recurrence (9.5 vs.19 month, p = 0.002), and a poorer median survival (17 vs. 43 month, p = 0.04). Esophageal adenocarcinoma in patients <40 years old commonly presents with an advanced stage of the disease and an associated poor survival. This is likely due to a low index of suspicion that dysphagia seen in younger patients is due to a malignancy.
Activation of Growth Hormone Short Loop Negative Feedback Delays Puberty in the Female Rat

Implantation of GH in the median eminence of the hypothalamus of 23-day-old female rats tonically inhibited serum GH levels throughout prepubertal development (days 23-36) and depressed GH diurnal pulsatile release. Puberty was significantly delayed in GH-deficient animals, a delay associated with a blunted in vitro ovarian steroidal responsiveness to gonadotropins (particularly estradiol) and a marked decrease in prepubertal uterine weight, as evaluated 4, 7, and 13 days after GH implantation. The prepubertal body weight increase was also depressed. Neither ovarian weight nor serum levels of LH, FSH, PRL, or TSH were consistently altered by the GH implant. In addition, evaluation of pulsatile PRL release in 33-day-old rats revealed no difference between control and GH-deficient animals. Ovarian LH receptor content was lower in GH-implanted rats than in controls, suggesting that a decrease in LH receptors may be one of the mechanisms by which a chronic decrease in serum gH depressed the prepubertal ovarian estradiol and, to a lesser extent, the progesterone response to gonadotropins. A direct ovarian site of action for GH was indicated by the results of experiments in which GH was administered to immature hypophysectomized estrogen-treated rats. The in vitro ovarian progesterone response of the GH-treated animals to both hCG and human FSH was distinctly increased by prior in vivo GH treatment. This effect of GH was not reproduced either by the in vivo administration of LH at a dose calculated by RIA to be contaminating the GH preparation or by FSH at a dose that induced a marked increase in aromatase activity in the same ovaries. GH treatment of hypophysectomized rats failed to affect either aromatase activity or hCG-induced estradiol release, indicating that GH does not directly facilitate the production of estradiol by the ovary. The fact that intact rats with GH implants did not actually show a decrease in the ovarian estradiol response to hCG but, rather, failed to show an increased response at the same time as control animals strongly suggests that ovarian maturation was delayed in GH-deficient rats. It is suggested that, in addition to PRL, GH may also play a role in the process of prepubertal reproductive development by enhancing the steroidal response of the ovary to gonadotropins.
Turbulent boundary-layer interaction with a shock wave at a compression corner

The local interaction of an oblique shock wave with an unseparated turbulent boundary layer at a shallow two-dimensional compression corner is described by asymptotic expansions for small values of the non-dimensional friction velocity and the flow turning angle. It is assumed that the velocity-defect law and the law of the wall, adapted for compressible flow, provide an asymptotic representation of the mean velocity profile in the undisturbed boundary layer. Analytical solutions for the local mean-velocity and pressure distributions are derived in supersonic, hypersonic and transonic small-disturbance limits, with additional intermediate limits required at distances from the corner that are small in comparison with the boundary-layer thickness. The solutions describe small perturbations in an inviscid rotational flow, and show good agreement with available experimental data in most cases where effects of separation can be neglected. Calculation of the wall shear stress requires solution of the boundary-layer momentum equation in a sublayer which plays the role of a new thinner boundary layer but which is still much thicker than the wall layer. An analytical solution is derived with a mixing-length approximation, and is in qualitative agreement with one set of measured values.
Use of confocal laser scanning microscopy (CLSM) for depthwise resolved microscale-particle image velocimetry (μ-PIV)

A novel use of confocal laser scanning microscopy (CLSM) makes the truly focused field-of-view with well-defined depthwise resolution possible for microscale particle image velocimetry (μ-PIV) applications. The operating principle of the CLSM is presented using the point spread function (PSF) that describes diffracted images of extremely small particles. The implemented high-speed CLSM system using a Nipkow rotating disk is applied to measure the microscale rotating Couette flow field confined between two parallel horizontal disks that are 180-μm apart, with the bottom one stationary and the top one rotating and seeded by 200-nm fluorescent spheres. The CLSM provides much distinct particle images in comparison with the conventional wide-field microscopy (WFM) and the measured vector profiles are more concentric and accurate depicting closer to an ideal Couette flow.
Effect of satisfaction with one's abilities on positive and negative affect among individuals with recently diagnosed rheumatoid arthritis.

Objective.The purpose of this study was to examine the effect that self-evaluation processes have on psychologic well-being among individuals with rheumatoid arthritis (RA). Methods.The study used a longitudinal research design with 4 data collection points. Participants were 227 adults with recently diagnosed RA. Data were collected via mailed questionnaire and telephone interview. Two dimensions of psychologic well-being were assessed—positive affect and negative affect. Results.We found that, among participants who viewed the abilities being evaluated as very important, greater satisfaction at time 1 was associated with less negative affect at time 2 and time 4. Satisfaction was not associated with positive affect at any of the time points, however. Conclusion.Study findings indicate that dissatisfaction with illness-related abilities can exacerbate psychologic distress. The findings also highlight the need for research examining the role that positive affect plays in adaptation to RA.
Influence of skin depth on NMR coil impedance

A derivation of the change in electrical impedance of an NMR surface coil produced by inductive coupling with a conducting medium is presented. The effect of skin depth is treated explicitly. Theoretical predictions of coil sample resistance and frequency offset are compared with those observed experimentally in a variety of circular surface coils and sample conductivities.
Autoradiographic evidence for epithelial origin of glucose-rich components of the basement membrane (basal lamina) and basement lamella in the skin of Fundulus heteroclitus

Autoradiography has been employed to investigate the site of origin of the adepithelial basement membrane, or basal lamina, of the skin of Fundulus heteroclitus. Both tritiated glucose and proline were used as radioactive precursors in organ culture. Glucose was progressively segregated and concentrated in two areas of the epithelium: (1) in the superficial layer of cells near the external surface, and (2) in the cortex of the basal layer near the basement membrane. After 12 hours the basement membrane was also labeled, and after 24 hours the epithelium, basement membrane (basal lamina), and basement lamella were all labeled. We have concluded that the label over the superficial layer of epithelium near the external surface of the fish represents glucose incorporation into mucous secretion products; and that label over the basal cell layer, basement membrane, and basement lamella represents synthesis by the epithelium of glucose-rich components, perhaps mucoproteins, of the basement membrane and of the ground substance of the basement lamella. Not all areas of the epithelium and underlying connective tissue incorporated glucose at the same time, and only after 24 hours were unlabeled areas of the skin eliminated. Proline incorporation was much less specific than that of glucose. Although the epidermis and dermis were heavily labeled, proline was incorporated in almost every tissue of the fish. The value of proline as a specific label for collagen is questioned.
Fail-Safe Dynamic Brake for Three-Phase Induction Machines

In several applications, a fail-safe brake (one designed to operate with loss of power) is required for three-phase induction machines. Typical braking methods for induction machines require external energy sources which are not fail-safe, or a mechanical friction brake which is costly and requires maintenance. A simple cost-effective fail-safe braking scheme is proposed for three-phase induction machines. Static and dynamic analyses of the proposed brake are presented along with analytical results. Experimental daia are included for comparison with the analytical results.
Low-energy, left-right-symmetry restoration in SO(N) grand unified theories

It is shown that a general n-step symmetry-breaking pattern of SO(4K+2) down to SU/sub C/(3) x SU/sub L/(2) x U/sub Y/(1), which uses regular subgroups only, does not allow low-energy left-right-symmetry restoration. In these theories, the smallest mass scale at which such restoration is possible is approx.10/sup 9/ GeV as in the SO(10) case. We also find that the unification mass in SO(4K+2) grand unified theories must be at least as large as that in SU(5). These results assume standard values of the Weinberg angle and strong coupling constant.
Tectonic controls on the nature of large silicic calderas in volcanic arcs

Silicic magma bodies stabilize the continental margin by redistributing low-density mate- rial into the upper crust. We examined the tectonic traits of 91 young, arc-related, silicic cal- deras to test previous assertions that the nature of voluminous silicic arc volcanism depends on specifi c tectonic characteristics. We fi nd that caldera occurrence positively correlates with convergence rate except in arcs with backarc spreading, which have few or no calderas. Cal- deras located on oceanic and young continental crust are predominantly dacitic, whereas rhyo litic calderas are mainly located on Mesozoic or older continental crust under extension. Occurrence does not increase with greater local subduction obliquity or duration of present arc activity. Our determination of controls on the formation and composition of silicic cal- deras in volcanic arcs contributes to the study of continental evolution.
Indoor Air Quality Survey of Nail Salons in Boston

Employees in nail salons, largely Vietnamese immigrant women in Boston, are exposed to a range of volatile organic chemicals from the products used in salons, including solvents, glues and polishes. Some of these chemicals have the potential to cause short and long-term adverse health effects. Only limited research has been performed on assessing occupational exposures. This project aimed to characterize total volatile organic compound (TVOC) and PM2.5 concentrations in nail salons as a function of ventilation, building characteristics, customer and employee occupancy, and type of services being performed. Students conducted sampling in 21 salons in Boston, MA from September to December, 2011. Study visits included: indoor environmental quality measurements (TVOCs, PM2.5 and carbon dioxide), site observations, and an interview. CO2 levels in 15 of 21 salons exceeded 800 ppm, suggesting that these salons may have insufficient ventilation. Higher TVOC and PM2.5 levels were found in salons with less ventilation (as estimated using CO2 concentrations). Contrary to our a priori hypothesis, average levels of TVOCs, CO2 and PM2.5 were consistent throughout salons, indicating that exposures may not be restricted to areas in the salon where work is being performed (e.g., at the manicure table). Higher TVOC concentrations were observed when tasks were being performed, yet were not dependent upon the number of tasks being performed. Improving ventilation conditions in salons to meet minimum outdoor air delivery requirements can reduce exposures to TVOCs.
Filtering high quality text for display on raster scan devices

Recently several investigators have studied the problem of displaying text characters on grey level raster scan displays. Despite arguments suggesting that grey level displays are equivalent to very high resolution bitmaps, the performance of grey level displays has been disappointing. This paper will show that much of the problem can be traced to inappropriate antialiasing procedures. Instead of the classical (sin x)/x filter, the situation calls for a filter with characteristics matched both to the nature of display on CRTs and to the human visual system. We give examples to illustrate the problems of the existing methods and the advantages of the new methods. Although the techniques are described in terms of text, the results have application to the general antialiasing problem—at least in theory if not in practice.
Determination of circulating blood volume using PIXE

Abstract The determination of the circulating blood volume using the PIXE method for measuring the time variation of the tracer concentration is described. The stable atomic tracer contained in widely-used drugs is introduced into the vascular system by injection. Two drugs containing bromine and iodine as tracers were tested. The experiment was performed in rabbits and in man. Additional information could be extracted from the shapes of the time variation of the concentration curve.
Domestic Institutions and the Taxing of Multinational Corporations

Political scientists have examined how domestic politics and the competition for international capital affect the setting of national tax rates. In this paper, I explore how political institutions, specifically the level of democracy, affect firm-level taxation across the world. I argue that electoral competition leads democratic governments to higher levels of taxation on firms. Using a data set on firm tax payments on the foreign affiliates of US multinational corporations from the US Bureau of Economic Analysis, I show that there are large variations within countries on the tax burdens faced by firms that are not explained by national tax rates. I find evidence that the mobility of the specific investment project, the types of spillovers these investments provide to a community, and attributes of the parent firm are all important determinants of taxation. While firm-level factors clearly affect corporate taxation, I argue that democratic institutions limit the offering of tax incentives and generate electoral benefits to policing tax avoidance by multinational corporations. After controlling for parent firm and foreign affiliate�level factors, I find that democratic countries generate as much as 26% more tax revenues from multinational corporations relative to authoritarian countries.
Institutional Arrangements for Public Debt Management

This paper analyzes institutional arrangements for public debt management by reviewing the experience of OECD countries during the late 1980s and 1990s. It discusses principal-agent issues arising from the delegation of authority from the Minister of Finance to the debt management office and describes how countries have designed governance structures and control and monitoring mechanisms to deal with these issues. The paper also discusses what lessons emerging market countries and transition countries can draw from the experience of advanced OECD countries. The OECD experience clearly indicates that-regardless of whether the debt management office is located inside or outside the Ministry of Finance-four issues are of vital importance: 1) Giving priority to strategic public policy objectives rather than tactical trading objectives. 2) Strengthening the institutional capacity to deal with financial portfolio management and with the public policy aspects of debt management. 3) Modernizing debt management. 4) Creating mechanisms to ensure successful delegation and accountability to the Ministry of Finance and Parliament.
L-tyrosine is a promising cancer vaccine adjuvant.

Meeting abstracts The choice of adjuvants is critical for any vaccine whether prophylactic or therapeutic. Our group previously showed that incomplete Freund's adjuvant, commonly used in different cancer vaccine trials, had many undesirable effects on T cell trafficking and function which directly
Classification of the Late Cambrian (Steptoean) trilobite genera Cheilocephalus Berkey, 1898 and Oligometopus Resser, 1936 from Laurentia

All recent work has assigned the genera Cheilocephalus Berkey, 1898 and Oligometopus Resser, 1936 to the family Cheilocephalidae Shaw, 1956, a small group of largely Laurentian trilobites from the Late Cambrian Steptoean Stage. New data from Nevada and Newfoundland indicate that the Cheilocephalidae is polyphyletic and that Cheilocephalus and Oligometopus are allied with different superfamilies. The Cheilocephalidae, which includes Cheilocephalus and Pseudokingstonia Palmer, 1965, is assigned to the Dameselloidea Kobayashi, 1935, and a pygidium from the Cow Head Group of Newfoundland indicates that Cheilocephalus first appears in the late Marjuman. The Dameselloidea disappeared on other continents at an extinction interval at the end of the Marjuman, but Cheilocephalus survived and underwent modest diversification in Laurentia in the succeeding Steptoean Stage. Oligometopus is transferred to the leiostegioidean family Leiostegiidae Bradley, 1925. The genus shows closest affinities with such Gondwanan gene...
Does the Content of Mothers' Verbal Stimulation Explain Differences in Children's Development of Verbal and Nonverbal Cognitive Skills?

The present study examined whether mothers’ verbal input at 3 years of age that specifies relations between objects, actions, and concepts (scaffolding) related to children’s development of verbal and nonverbal cognitive skills from 3 through 6 years of age. We were particularly interested in whether these relations differed for children who varied in their levels of biological risk (full term, n 5 114; preterm, n 5 198). Mothers’ scaffolding when children were 3 years of age occurred on average in about 18% of the interactions observed in everyday situations in the home. Growth-curve modeling revealed that, for all children, scaffolding predicted verbal and nonverbal skills even after controlling for families’ socioeconomic status and frequency of maternal stimulation. Scaffolding was more strongly related to preterm as compared to full-term children’s growth in nonverbal skills. Preterm children with mothers who used scaffolding more frequently had nonverbal skill development that more closely approximated that of full-term children. However, by 6 years, all children in this predominately low-income sample displayed low cognitive age scores. Experimental studies would be the next step to determine if increasing this type of verbal interaction would foster more optimal outcomes. © 2000 Society for the Study of School Psychology. Published by Elsevier Science Ltd
Late-onset post-concussion symptoms after mild brain injury: the role of premorbid, injury-related, environmental, and personality factors

The present study investigated the possible role of a number of pre- peri-, and post-traumatic factors in the experience of post-concussion syndrome (PCS). These factors included: (1) history of premorbid risk factors, (2) severity of injury, and (3) post-morbid functioning and environmental factors. Subjects were 55 persons with mild brain injury. PCS was defined in terms of the severity and impact of 'late-onset' symptoms. Pre- and peri-traumatic factors were not associated with level of PCS symptom impact. Among post-traumatic factors, only level of psychological distress was strongly associated with impact level. The results suggest the importance of psychological factors in prolonged PCS.
Ideology and Politics: The Rechtsstaat Idea in West Germany

W hen in 1970 Chancellor Willy Brandt of West Germany exchanged visits with the East German Prime Minister, Willi Stoph, he began a new approach to the old problem of a divided Germany. The problem is one of many that politicians in West Germany's Federal Republic have faced as part of the legacy of the Nazi era. Since the founding of the Republic in 1949, West German politics has been marked by a widespread belief in a set of value judgments that have seemed to prohibit Governments from dealing with problems from the past in ways that otherwise had much to commend them. It was once thought, for example, that if these value judgments were to govern West German politics it would be impossible for exchanges like the one between Brandt and Stoph to take place, or for Nazi criminals apprehended after a certain date to be prosecuted. Belief in these value judgments is itself a product of the Nazi experience, though that alone is not a sufficient explanation. The value judgments form an ideology, if we take "ideology" to mean a set of interrelated ideas about human beings and their interactions, at least some of which are value judgments and all of which are believed. The value judgment discussed here have as their theme the rule of law; taken together they constitute the idea of the Rechtsstaat. My purpose is to examine the Rechtsstaat idea, to offer an adequate explanation of the belief in it, and to show how this belief has affected political behavior in West Germany.
Silence of the strands: RNA interference in eukaryotic pathogens

Double-stranded (ds) RNA interference (RNAi) is a recent technological advance that enables researchers to reduce gene expression at the post-transcriptional level. This form of RNA silencing is initiated by dsRNA, expressed in or introduced into a cell of interest, which triggers homology-dependent degradation of the corresponding mRNA. This versatile technique has remarkable promise as a tool for the study of eukaryotic pathogens. Protozoan parasites and pathogenic fungi often resist manipulation using standard molecular genetic approaches. Researchers studying these organisms need flexible molecular tools, particularly to exploit newly sequenced genomes; this review offers a practical guide to establishing RNAi in pathogenic eukaryotes.
Four‐phase single‐capillary stepwise model for kinetics in arterial spin labeling MRI

An extended model for extracting measures of brain perfusion from pulsed arterial spin labeling (ASL) data while considering transit effects and restricted permeability of capillaries to blood water is proposed. We divided the time course of the signal difference between control and labeled images into four phases with respect to the arrival time of labeled blood water at the voxel of interest (t(A)), transit time through the arteries in the voxel (t(ex)), and duration of the bolus of labeled spins (tau). Dividing the labeled slab of blood water into many discrete segments, and adapting numerical integration methods allowed us to conveniently model restricted capillary-tissue exchange based on a modified distributed parameter model. We compared this four-phase single-capillary stepwise (FPSCS) model with models that treat water as a freely diffusible tracer, using both simulations and experimental ASL brain imaging data at 1.5T from eight healthy subjects (24-80 years old). The FPSCS model yielded less errors in the least-squares sense in fitting brain ASL data in comparison with freely diffusible tracer models of water (P = 0.055). These results imply that restricted permeability of capillaries to water should be considered when brain ASL data are analyzed. Magn Reson Med 53:511-518, 2005. Published 2005 Wiley-Liss, Inc.
Two-dimensional modal analysis based on maximum likelihood

The authors present a method for estimating the parameters of 2-D damped harmonic (modal) signals in additive Gaussian noise. This method applies in the cases of single or multiexperiment data and incoherent or coherent signals. Both synthesis and analysis models for the data are developed. Central to these models are the signal and orthogonal subspaces. Under the assumption of distinct modes in one of the two dimensions, there exists an invertible function between the parameters of these two subspaces. This function can be used to express the optimization problem given by maximum likelihood in terms of the orthogonal subspace. The resulting problem can be solved by any of several methods, including total least squares and iterative quadratic maximum likelihood (IQML). >