cssi/SciSciGPT-SciSciNet huggingface dataset:
Influence of plasticizer configurational changes on the dielectric characteristics of highly plasticized poly(vinyl chloride)

Abstract Three citrate-related compounds [Citroflex A-4 (CFA4), Citroflex A-6 (CFA6), and Citroflex B-6 (CFB6)] and six sebacate-related compounds [dimethyl sebacate (DMS), diethyl sebacate (DES), dibutyl sebacate (DBS), dioctyl sebacate (DOS), dioctyl azelate (DOZ), and dioctyl adipate (DOA)] were used to evaluate the effects of configurational changes in plasticizer on the dielectric properties of ion-selective poly(vinyl chloride) membranes. Tridodecylamine (TDDA) and potassium tetrakis-4-chlorophenyl borate (KTpCIPB) were used as neutral charge carriers and negative sites, respectively. Using parallel plate sensors, the dielectric properties [ionic conductivity (σ) and tan δ] of the plasticized PVC membranes were determined at temperatures from − 100 to + 100°C and seven log frequencies (− 1, 0, 1, 2, 3, 4, and 5 Hz). Generally, increasing the amount of plasticizer in the membrane improved the σ and lowered the temperature of the tan δ peak. A positive linear correlation existed between the log σ and the log phr ratio for a given temperature and frequency, when no data was included for membranes below the melting temperature of the plasticizer. When plotted versus temperature, the slopes of all these lines passed through a maximum between 0 and 60°C. The intercepts of all these lines increased monotonically with increasing temperature. These intercepts were highly dependent on the frequency at low temperatures, becoming less frequency dependent as the temperature increased. Having established that configurational changes of the plasticizers had no effect above the melting point of each plasticizer, global nomograms were only required for the citrate- and sebacate-related plasticizers, respectively. Using the appropriate nomogram for a selected plasticizer, the σ could be predicted at a given phr ratio, temperature, and frequency.
Phenomenological approach to high-spin quantum fields based on the Weinberg formalism.

We investigate the possibility of constructing a covariant phenomenology of high-spin particles based on the work of Weinberg. We put forth a simple algebraic method for investigating the dispersion relations E=E(p,m) satisfied by the solutions to the free-particle Weinberg equations. We find that these equations support solutions which do not satisfy ${\mathit{E}}^{2}$=\ifmmode\pm\else\textpm\fi{} \ensuremath{\surd}${\mathbf{p}}^{2}$+${\mathit{m}}^{2}$. This motivates a proposal to build the phenomenology without explicit reference to a wave equation. We demonstrate the practicality of this approach by providing techniques for constructing the covariant spinors, free-particle field operators, and propagators which could then be used to construct a covariant perturbation theory.
Diffusion of oxygen in tantalum-based alloys

Abstract The diffusivity of oxygen in tantalum and tantalum-based alloys was determined from EMF measurements on solid electrolytic cells over the temperature range of 873–1373 K (600–1100°C). Oxygen diffusion in tantalum was slightly decreased by small additions of Nb, V, Mo, Ni and Ti. Several percent of Mo and W in tantalum have a larger effect in lowering oxygen diffusivity, and Cr was particularly effective, lowering the oxygen diffusivity by more than an order of magnitude. A trapping model was used to bit diffusion data in tantalum-based alloys, and the trapping energies were compared with thermodynamic quantities and with calculated values of elastic interaction energy. The agreement was not good.
Oscillatory flow and mass transport in a curved tube

Transport of soluble material is analysed for volume-cycled oscillatory flow in a curved tube. The equations of motion are solved using a regular perturbation method for small ratio of tube radius to radius of curvature and order unity amplitude over a range of the Womersley parameter. The transport equation is similarly solved by a regular perturbation scheme where uniform steady end concentrations and no wall flux are assumed. The time-average axial transport of solute is calculated. There is substantial modification of transport compared to the straight-tube case and the results are interpreted with respect to pulmonary gas exchange.
Radius ratio effect on high-strain rate properties of syntactic foam composites

The high-strain rate compressive properties of syntactic foams are characterized in this study. This study is performed using a pulse-shaped Split-Hopkinson Pressure Bar technique. Nine different types of syntactic foams are fabricated with the same matrix resin system but three different size microballoons and three different microballoon volume fractions. The microballoons have the same outer radius of 40 μm, but different internal radii leading to a difference in their densities. The volume fractions of the microballoons in the syntactic foams are maintained at 0.1, 0.3, and 0.6. Analysis is carried out on the effect of the microballoon radius ratio at each volume fraction on the high-strain rate properties. This approach is helpful in separating and categorizing the contribution of matrix and microballoons to the dynamic compressive properties of syntactic foams. The results at high-strain rates are compared to quasi-static strain rate compressive properties of the same material. The results show that there is little or no significant change in both compressive strength and modulus of syntactic foams at all radius ratios when tested at strain rates of 400–500/s compared to quasi-static rates. However, higher dynamic strength and stiffness values are obtained consistently at all radius ratios when tested at 800–1000/s compared to quasi-static values. It is observed that the radius ratio does not affect the syntactic foam properties significantly when tested at the same high-strain rate and volume fraction. Scanning electron microscopy is carried out to understand the fracture modes of the syntactic foams.
Optical manipulation of single electrically charged biological particles

In this paper, we study optical trapping and manipulation of single electrically charged colloidal particles. We measured the dynamic motion of a charged particle captured in a linearly polarized optical trap. We found that the position's fluctuation of a trapped particle in the parallel direction to the lase polarization is larger than that in the normal direction to the polarization, which suggests that there exists an additional electric force parallel to the laser polarization direction exerting on the charged particle beside the known radiation forces on the dielectric particle. This asymmetry in dynamic motion is significant when the particle size is less than the wavelength of the trapping laser. We present both the theoretical and experimental results.
Operant Response in Infants as a Function of Time Interval Following Signal Onset

This study investigated the hypothesis that estimates of infant auditory threshold are lowered by extending the duration of individual test trials such that infants have more time to detect and res...
The theory of empirical sequences

In this paper I want to accomplish three things: First, I want to present a 'formal system' for L. E. J. Brouwer's conception of elementary analysis. Secondly, I want to prove two meta-theorems about the proposed system; and finally, I want to use those results to speculate about a historical question in Brouwer scholarship that was left open at the end of Posy (1976). By elementary analysis I mean the theory of the arithmetic of real numbers which treats them as infinite sequences of natural numbers. Thus the paper revolves around a portrayal of Brouwer's conception of numerical sequences, but before discussing the special features of the formal system that follows let me mention two devices that figure centrally in my portrayal of Brouwer's thought about that sort of choice sequence. My primary device is a version of Brouwer's theory of the creative subject. I shall develop that theory here and also generalize its applications to analysis. In (1976) I1 distinguished two versions of the theory of choice sequences: the theory of general sequences (Brouwer's explicit theory throughout his early and middle carreer) and the theory of epistemic sequences (which occured explicitly only after 1948). The latter study concerns sequences which are themselves generated by empirical observations about the activity of the creative subject. The theory of empirical sequences, which I formalize here, is a natural generalization of the latter epistemic approach, and allows any series of events at all or more precisely any series of trials with a determinate number of possible outcomes to generate a choice sequence. The theory of empirical sequences implicitly alluded to by Brouwer and Heyting was first explicitly proposed by Myhill (in 1968a and 1970) and mentioned in Troelstra (1969), but the present paper explores it systematically for the first time. Of course in the more general empirical approach of this paper the basic idea of the creative subject has not vanished. He is still around both as an observer and occasionally (though now merely a special case) as a generator
Effects of Cholesterol on Physical Properties of Human Erythrocyte Membranes: Impact on Susceptibility to Hydrolysis by Secretory Phospholipase A2

The ability of secretory phospholipase A(2) (sPLA(2)) to hydrolyze cell membranes is highly dependent on the physical properties of the membrane. The effects of cholesterol on these properties have been characterized in artificial bilayers and found to alter sPLA(2) activity significantly. It is hypothesized that the natural difference in cholesterol content between erythrocytes and leukocytes is in part responsible for their differing susceptibility to hydrolysis by sPLA(2). To test this hypothesis, defined amounts of cholesterol were removed from erythrocyte membranes using methyl-beta-cyclodextrin. Treatment of cells with methyl-beta-cyclodextrin increased the hydrolysis rate and total substrate hydrolyzed by sPLA(2). In general, this effect of cholesterol removal was more pronounced at higher temperatures. Comparison of the level of membrane order (assessed with the fluorescent probe laurdan) with hydrolysis rate revealed that sPLA(2) activity was greatly enhanced upon significant reductions in lipid order. Additional treatment of the cells with calcium ionophore further enhanced the hydrolysis rate and altered the relationship with membrane order. These data demonstrated that interactions with sPLA(2) observed in artificial bilayers apply to biological membranes. It is also proposed that the high level of cholesterol in erythrocyte membranes is a protective mechanism to guard against hydrolytic enzymes.
A stochastic model for the formation of channel networks in tidal marshes

[1] Salt marshes are often dissected by a network of channels formed by tidal oscillations and related water fluxes. In this note we present a stochastic model able to simulate the formation and evolution of tidal networks in salt marshes. The model is based on a simplification of the shallow water equations that enables the determination of the water surface gradients on the marsh platform and related bottom shear stresses. The governing equations are then solved with a random walk algorithm in an enclosed domain representing the marsh platform and its physical boundaries. Model results show how the development of the network depends on the tidal forcing, the critical shear stress for erosion, as well as the local heterogeneities in vegetation and sediment substrate.
Developing High-Quality Field Program Sounding Datasets

Enormous resources of time, effort, and finances are expended in collecting field program rawinsonde (sonde) datasets. Correcting the data and performing quality control (QC) in a timely fashion after the field phase of an experiment are important for facilitating scientific research while interest is still high and funding is available. However, a variety of issues (different sonde types, ground station software, data formats, quality control issues, sonde errors, etc.) often makes working with these datasets difficult and time consuming. Our experience working with sounding data for several field programs has led to the design of a general procedure for creating user-friendly, bias-reduced, QCed sonde datasets. This paper describes the steps in this procedure, gives examples for the various processing stages, and provides access to software tools to aide in this process.
Calculation of Landé g factors for III-V nanowhisker quantum dots and comparison with experiment

The coupling between a magnetic field and the spin of an electron confined to a quantum dot is determined by the $g$ factor, which is strongly affected by the structure of the dot. Uncertainties in a dot's geometry and composition can obscure quantitative comparison of theory and experiment. Nanowhisker quantum dots (NWQDs) provide a well-controlled structure that is ideal for such comparison. We have performed detailed three-dimensional numerical calculations of the electronic properties of NWQDs consisting of an $\mathrm{In}\mathrm{P}∕\mathrm{In}\mathrm{As}∕\mathrm{In}\mathrm{P}$ quantum well embedded in a [111] oriented InAs nanowhisker. We have computed $g$ factors, confinement energies, and wave functions for valence and conduction states as a function of dot size. The calculations are in excellent agreement with experiments and differ markedly from $g$ factors obtained from extrapolation of bulk formulas, providing strong confirmation of the effect of angular momentum quenching. The closeness of our results to experiment enables us to identify critical well and barrier widths yielding $g\ensuremath{\approx}0$, which are important for technological applications. We also predict larger and more negative $g$ factors for $\stackrel{P\vec}{B}$ oriented along [111]. The calculations were carried out using eight-band strain-dependent $k∙p$ theory in the envelope-function approximation using a finite difference technique on a real-space grid.
Transverse isotropic elastic moduli and in-plane thermal diffusivity in silicon-supported thin films of a photosensitive polyimide measured using impulsive stimulated thermal scattering

Abstract Through impulsive stimulated thermal scattering, the elastic and thermal properties of silicon-supported thin films (2–11 μm thicknesses) of a new low-CTE (coefficient of thermal expansion) photosensitive polyimide based on a biphenyl dianhydride/p-phenylenediamine backbone were studied. The material was found to be mechanically anisotropic. The in-plane thermal diffusivity and the in-plane and through-plane shear and longitudinal sound speeds were determined.
A computer simulation of an amorphous thin film on a crystalline substrate

Abstract We employ the Monte Carlo simulation method of classical statistical mechanics to study the structure and energetics of the crystal/amorphous interface. The interface is found to be approximately four atomic layers thick and provides good bonding between the amorphous and crystalline phases.
Distressing aspects of women's roles, vicarious stress, and health consequences.

Individuals internalize the roles they play and the statuses they occupy in their social networks. It logically follows that the benefits and costs of women's role commitments may be critically important to their physical and mental health. This literature review focuses on distressing or negative aspects of enacting the specific primary roles of workel wife, and mother. Vicarious stress and inadequate social support for women in these roles may contribute to immuno suppression and disease vulnerability. Some women may choose the sick role as a means of escape from taxing role responsibilities. Future directions for women's health research are suggested, along with adoption of an empowerment model of health.
The Multiple Risk Factor Intervention Trial (MRFIT) A Return to a Landmark Trial

In 1982 the results of the landmark Multiple Risk Factor Intervention Trial (MRFIT) were published in JAMA . 1 MRFIT was a randomized primary prevention trial funded by the National Heart and Lung Institute (now the National Heart, Lung, and Blood Institute) to test whether multifactor intervention in 12 866 high-risk, asymptomatic middle-aged men would prevent fatal coronary heart disease (CHD) events compared with usual care. Minimum follow-up was 6 years. MRFIT grew from the Task Force on Arteriosclerosis convened in 1970 by the National Heart and Lung Institute to devise a long-range strategy for preventing, treating, and controlling arteriosclerosis and its complications. 2 The task force thoroughly reviewed data that had come from epidemiologic observations in the United States and abroad—including the findings of the Framingham Heart Study, the Seven Countries Study, and the Chicago Workers Study—and from clinical observations and smaller clinical trials linking risk factor modification
On Nonprojective Block Components of Lefschetz Characters for Sporadic Geometries

This work examines the possible projectivity of 2-modular block parts of nonprojective Lefschetz characters over 2-local geometries of several sporadic groups. Previously known results on M 12, J 2, and HS are mentioned for completeness. The main new results are on the sporadic groups Suz, Co 3, Ru, O′N, and He. For each group, the Lefschetz character is calculated, and its 2-modular block parts are examined for projectivity. In each case it is confirmed that a nonprincipal block part contains a nonprojective summand. The case of O′N is additionally found to have a nonprojective summand in its principal block part. Nineteen of the sporadic groups (including many previously known cases) are categorized into three classes based on projectivity properties of their Lefschetz characters.
Influence of sodium bicarbonate on growth and health of young calves.

Fifty-four Holstein and Jersey calves were assigned at 4 days of age within breed and sex to one of four treatments: control consisting of colostrum, milk replacer, and starter; buffered colostrum and replacer (.6% sodium bicarbonate) and starter (2% sodium bicarbonate); acidified colostrum (1% propionic), untreated replacer, and starter; and acidified, buffered colostrum (1% propionic, .6% sodium bicarbonate), buffered replacer (.6% sodium bicarbonate), and starter (2% sodium bicarbonate). The feeding regimen was colostrum once daily, day 4 to 14; milk replacer once daily, day 15 to 28; and calf starter ad libitum, day 4 to 84. Bull calves were fed for 42 days and heifers for 84 days. Calves fed acidified colostrum refused more feed and were less efficient from day 4 to 14 than calves fed buffered colostrum. Bulls were more sensitive to acidified colostrum than heifers. Starter intake, total dry matter intake, and average daily gains were similar for all calves during days 4 to 84. Rumen fluid from calves fed diets with sodium bicarbonate was higher in acetate and lower in propionate and lactate than that from calves fed diets without sodium bicarbonate. Sodium bicarbonate improved intake of acidified colostrum during the first 2 or 3 days of feeding but had no other effect on gain or feed intake.
The effect of continuing education on the test scores of a state licensing board examination

Recent legislation in Wisconsin allows optometrists to use topical diagnostic pharmaceutical agents. Among the provisions of the legislation was that optometrists must satisfactorily complete an examination on pharmacology before being certified to use these agents. This study compares the scores optometrists obtained on the examination with years since licensure and the type of continuing education participation preceding the examination. Recent licensees scored better than those licensed before 1953. Optometrists licensed after 1972 who had participated in some type of continuing education activity before the examination scored significantly better than those licensed after 1972 who had not. Results show that an intensive course can bring older graduates up to a level of knowledge similar to current licensees and that formal continuing education participation may improve test scores to a greater extent than individual preparation for an examination.
An instrument for colorectal anastomosis without sutures

A new instrument for joining the colon to the lower part of the rectum without sutures has been described. Initial tests in dogs and its use in one patient have been satisfactory. Further trial of the device is considered justified.
All Politics Is Local: The Reemergence of the Study of City Politics

The study of local politics has been relegated to the periphery of political science and many explanations have been offered for the marginalization of the subfield. I offer three related arguments for why scholars should revisit the study of sub-state politics. First, the local level is the source of numerous political outcomes that matter because they represent a large proportion of political events in the United States. Secondly, there are methodological advantages to studying local politics. Finally, analyzing politics at the sub-state level can generate thoroughly different kinds of questions than a purely national-level focus and can offer different answers to questions that apply more generally. Research on local politics can and should contribute to broader debates in political science and ensure that we understand both how and why cities are unique.
Shaping and Discriminative Control of Underwater Click Vocalizations in a California Sea Lion

A captive vea lion (Zalophus californianus) which had never before produced clicking sounds in the laboratory was first conditioned to vocalize in air and subsequently learned to emit underwater clicks. clicking was brought under control by differential reinforcement procedures. Vocalization as an indicator response may be useful in the comparative study of discriminative behavior.
Non-strictly Hyperbolic Systems, Singularity and Bifurcation

This paper examines the effect of non-strict hyperbolicity on singularity formation for a quasilinear 2$$\,\times \,$$×2 system. We will show that for appropriate data a singularity can form solely along a curve in the (x, t) plane where strict hyperbolicty is lost. Furthermore, this curve may bifurcate at some point. Numerous examples are considered for Riemann and smooth data.
On flow of a Navier-Stokes fluid in curved pipes. Part I: Steady flow

Abstract We consider the steady, fully developed motion of a Navier–Stokes fluid in a curved pipe of cross-section D under a given axial pressure gradient G . We show that, if G is constant, this problem has a smooth steady solution, for arbitrary values of the Dean’s number κ , for D of arbitrary shape and for any curvature ratio δ of the pipe. This solution is also unique for κ sufficiently small. Moreover, we prove that the solution is unidirectional (no secondary motion) if and only if κ = 0 . Finally, we show the same properties for the approximations to the Navier–Stokes equations called “Dean’s equations” and provide a rigorous way in which solutions to the full Navier–Stokes equations approach those to this approximation in the limit of δ → 0 .
DIABETES MELLITUS ASSOCIATED WITH HYPERTHYROIDISM1

A well-established clinical rule has been stated many times that, whenever possible, the clinical signs and symptoms of a patient should be explained with a single diagnosis. This rule breaks down most frequently when dealing withthe insidious symptoms of chronic disease in contrast with the dramatic manifestations of acute illness. The differential diagnosis of diabetes mellitus and hyperthyroidism is particularly meticulous. This fact is explained by the similarity or actual identity of cardinal symptoms of the diseases. Polyphagia, polydypsia, weight loss, and strength loss are common factors in both diabetes mellitus and hyperthyroidism. Glucose is frequently found in the urine of the patient with hyperthroidism, and hyperglycemia is common. The glycosuria and hyperglycemia are due, however, to a different mechanism in each of the two diseases. In hyperthyroidism, glycogenolysis is accelerated and, in diabetes, oxidation of glucose is insufficient. In both instances, the liver is rendered low in glyco...
An inventory of 13C abundances in coastal wetlands of Louisiana, USA: vegetation and sediments.

Organic carbon-rich sediments from the surface of fresh, intermediate, brackish and salt marshes of coastal Louisiana were sampled and analyzed for their 13C content. The average ∂13C from all sites within each wetland type was-27.8‰,-22.1‰,-16.9‰, and-16.2‰, for fresh, intermediate, brackish and salt marshes, respectively. Means from the fresh, intermediate and brackish marshes were significantly different at the 0.01 level. A mixing model using measurements of standing crop and ∂13C of plant carbon was applied to estimate the contribution of each species to the sedimentary carbon at four of the marsh sites. Sedimentary ∂13C values generally reflected that of the dominant species present at each site. Brackish and salt marsh samples, however, showed a negative shift of ∂13C with respect to whole plant carbon. We interpret these depeleted ∂13C values to be the result of more extensive organic matter decomposition and selective preservation of 13C-depleted refractory components in sediments from saline sites. The results of this study suggest that ∂13C composition of sedimentary carbon may offer a valuable tool for distinguishing subtle changes in paleohydrology of wetlands resulting from relative sea level changes.
Optimum conditions for successful transplantation of immature rat retina to the lesioned adult retina

We have previously reported the successful transplantation of neonatal rat retina to the lesioned retinas of adult host rats. The current studies provide a much more in-depth evaluation of the optimal conditions under which successful grafting can be achieved. Utilizing the same surgical approach and techniques as in our earlier studies, the variables of host lesion conditioning and donor age were investigated. The grafts were evaluated for survival, location, and degree of achievement of selected histological characteristics. The latter category was organized into an evaluation index (E.I.) which provided a consistent system of scoring for purposes of inter-group comparisons. In order to study the effects of lesion conditioning, neonatal grafts were delivered into fresh (0), 1, 2, 4, and 8 week conditioned lesions. Excellent survival and placement were observed at all conditioning times examined. Even the E.I. failed to reveal any statistically significant differences among the lesion conditioning groups. However, there was the suggestion of reduced scarring in the older, more stable lesion groups. The second portion of the study, dealing with donor age, involved the transplantation of E14, E16, E20, PN1, and PN10 retina into freshly lesioned sites in the host retina. Again the result was excellent overall graft survival and placement in all groups. The E.I. score, however, revealed highly significant differences between PN10 grafts and those from all other groups tested. These differences were revealed for all histological criteria with the exception of non-neuronal barrier formation. These studies show the utility of the current model for the repair of retinal lesions over an extended post-traumatic period as well as revealing the wide developmental window for harvesting retinal tissue for the purpose of intravitreal transplantation.
Finding the atomic configuration with a required physical property in multi-atom structures

In many problems in molecular and solid state structures one seeks to determine the energy-minimizing decoration of sites with different atom types. In other problems, one is interested in finding a decoration with a target physical property (e.g. alloy band gap) within a certain range. In both cases, the sheer size of the configurational space can be horrendous. We present two approaches which identify either the minimum-energy configuration or configurations with a target property for a fixed underlying Bravais lattice. We compare their efficiency at locating the deepest minimum energy configuration of face centered cubic Au-Pd alloy. We show that a global-search genetic-algorithm approach with diversity-enhancing constraints and reciprocal-space mating can efficiently find the global optimum, whereas the local-search virtual-atom approach presented here is more efficient at finding structures with a target property.
Estimating the potential for methane clathrate instability in the 1%‐CO2 IPCC AR‐4 simulations

[1] The recent work of Reagan and Moridis (2007) has shown that even a limited warming of 1 K over 100 years can lead to clathrate destabilization, leading to a significant flux of methane into the ocean water, at least for shallow deposits. Here we study the potential for methane clathrate destabilization by identifying the 100-year temperature increase in the available IPCC (Intergovernmental Panel on Climate Change) AR-4 1%-CO2 increase per year (up to doubling over pre-industrial conditions, which occurs after 70 years) simulations. Depending on assumptions made on the possible locations (in this case, only depth) of methane clathrates and on temperature dependence, our calculation leads to an estimated model-mean release of methane at the bottom of the ocean of approximately 560-2140 Tg(CH4)/year; as no actual geographical distribution of methane clathrates is considered here, these flux estimates must be viewed as upper bound estimates. Using an observed 1% ratio to estimate the amount of methane reaching the atmosphere, our analysis leads to a relatively small methane flux of approximately 5–21 Tg(CH4)/year, with an estimated inter-model standard deviation of approximately 30%. The role of sea-level rise by 2100 will be to further stabilize methane clathrates, albeit to a small amount as the sea-level rise is expected to be less than a few meters.
Spectral relations of supply noise and jitter with regular and feed forward clocking schemes

High frequency supply noise affects chip performance in mechanisms that go beyond logic path failures due to voltage drops. One of the dominant chip performance degradation mechanisms due to high frequency noise is the direct introduction of clock jitter. Basic modeling studies powered by Fourier analysis help establish a clear and fundamental understanding of how noise is translated into jitter in the clock distribution path. In this context oscillator feed forward mechanism is also explored and analysis of its spectral response reveals how, once tuned properly, it benefits frequency boost.
Assessment of blinding in clinical trials

Success of blinding is a fundamental issue in many clinical trials. The validity of a trial may be questioned if this important assumption is violated. Although thousands of ostensibly double-blind trials are conducted annually and investigators acknowledge the importance of blinding, attempts to measure the effectiveness of blinding are rarely discussed. Several published papers proposed ways to evaluate the success of blinding, but none of the methods are commonly used or regarded as standard. This paper investigates a new approach to assess the success of blinding in clinical trials. The blinding index proposed is scaled to an interval of -1 to 1, 1 being complete lack of blinding, 0 being consistent with perfect blinding and -1 indicating opposite guessing which may be related to unblinding. It has the ability to detect a relatively low degree of blinding, response bias and different behaviors in two arms. The proposed method is applied to a clinical trial of cholesterol-lowering medication in a group of elderly people.
Graded Coronagraphic Masks for High-Contrast Near-Infrared Imaging

We present here results from an experimental and theoretical study in the use of graded focal-plane occulting masks to improve high-contrast astronomical imaging at near-infrared wavelengths. The study includes investigations of both high-energy beam sensitive (HEBS) glass (a product of Canyon Materials, San Diego, CA) and binary notch-filter technologies to create precision graded occulting masks. In conjunction with this investigation, we conduct computer simulations showing expected high-contrast levels for various graded masks being considered for installation in the PHARO camera of the Palomar 200-inch (5m) Hale Telescope Adaptive Optics (AO) system. Our results demonstrate that the implementation of a graded exponential mask in the Palomar system should improve high-contrast sensitivities by about 2.4-mag in K-band (2.0-2.4 μm), for 0.75-1.5 arcsec separations. We also demonstrate that both HEBS and binary notch-filter technologies present adequate platforms for necessary occulting requirements. We conclude with a discussion of theinsights our study yields for planned space-based high-contrast observatories such as NASA's planned Terrestrial Planet Finder Coronagraph (TPF-C) and the proposed Eclipse mission.
Effect of interferon α on pokeweed mitogen-induced differentiation of human peripheral blood B lymphocytes

Abstract The effect of human leukocyte interferon (IFN-α) on pokeweed mitogen (PWM)-triggered differentiation of human B cells has been studied in vitro. Graded doses of IFN-α were added to the culture of human peripheral blood monocytes, and total antibody synthesis was measured after 6 to 7 days of culture by using a highly sensitive reverse hemolytic plaque assay. The results suggest that a low dose (102 U/ml) enhances and a high dose (104 U/ml) suppresses B-cell differentiation. Its action occurred in an early stage of B-cell differentiation. Since PWM-triggered differentiation of human B cells requires T cells and monocytes in the culture, we have examined separately the effects of IFN-α on T cells and monocytes. The data indicate that enhancement was mediated by activation of monocytes and suppression was due to inhibition of helper T-cell proliferation. At a high dose, B-cell proliferation may be also directly inhibited by IFN. The implication of these findings is discussed with regard to immuno-regulation during viral infection.
Radiation measurements from Alcator C-Mod initial operation

Operation of the Alcator C-Mod experiment, a compact high field tokamak, resumed in April, 1993. This experiment is ultimately expected to produce neutron rates of 5/spl times/10/sup 15/ n/s for 1 second long pulses at 20 minute intervals. The radiation detection system is comprised of a number of components for examination of specific aspects of the resulting ionizing radiation fields. Six fission detectors and 2 BF/sub 3/ counters which are mounted inside two moderator stations are used for detecting the global neutron production on each shot. Environmental thermoluminescent detectors (TLD's), sensitive to both neutrons and /spl gamma/-rays, are placed at distributed points both inside and outside of the facility. Self-reading dosimeters (SRD's), neutron bubble dosimeters, and film badges are also used to check the daily and monthly radiation production. Portable instrumentation capable of integrating the radiation signals from short pulse operation is available in order to survey biological shield penetration leakage. Tracerlab area monitors have been installed to measure the activated background levels in the test cell. Details of these systems are discussed, and the initial measurement results are presented.
Segmentation of rodent brains from MRI based on a novel statistical structure prediction method

Functional segmentation of brain images is important in understating the relationships between anatomy and mental diseases in brains. Volumetric analysis of various brain structures such as the cerebellum plays a critical role in studying the structural changes in brain regions as a function of development, trauma, or neurodegeneration. Although various segmentation methods in clinical studies have been proposed, most of them require a priori knowledge about the locations of the structures of interest, preventing the fully automatic segmentation. In this paper, we present a novel method for detecting and locating the brain structures of interest that can be used for the fully automatic functional segmentation of 2D rodent brain MR images. The presented method focuses on detecting the topological changes of brain structures based on a novel area ratio criteria. The mean successful rate of the detection method shows 89.4% accuracy compared to the expert-identified ground truth.
Identification of predictive factors for early neoplasia in Barrett's esophagus after autofluorescence imaging: a stepwise multicenter structured assessment

Background Autofluorescence imaging is a novel imaging technique that may improve the detection of early neoplasia in Barrett's esophagus. Autofluorescence imaging is, however, associated with a 40% to 81% false-positive rate. Objective Our purpose was to identify endoscopic features that may predict the presence of early neoplasia in autofluorescence-positive areas. Design Descriptive and prospective cohort study. Setting Tertiary referral centers for the detection and treatment of early Barrett's neoplasia. Patients and Methods Patients undergoing autofluorescence endoscopy. High-quality images with autofluorescence imaging and white-light endoscopy were obtained with corresponding histologic study. A systematic image evaluation process was performed, including an unblinded orientation phase (10 areas), a blinded derivation phase, and a blinded validation phase by 5 international experts in autofluorescence imaging (80 areas). Subsequently the identified features were validated in a prospective pilot study. Main Outcome Measurements Association between endoscopic features and presence of early neoplasia in autofluorescence-positive areas. Results Autofluorescence intensity, proximity of gastric folds Limitation Selected set of images from a high-risk population (tertiary referral center). Conclusion We found specific endoscopic features that were associated with early neoplasia in autofluorescence-positive areas. These findings can be used in future prospective studies to improve the accuracy of autofluorescence imaging without performing magnification endoscopy for detailed inspection of suspicious areas.
CHORDEE CORRECTION BY CORPORAL ROTATION: THE SPLIT AND ROLL TECHNIQUE

AbstractPurpose: The optimal approach to correcting ventral chordee associated with severe hypospadias is controversial. Dorsal plication tends to shorten the phallus and ventrally positioned grafts often mandate a staged procedure. An alternative approach is presented using corporal rotation to correct ventral chordee associated with hypospadias.Materials and Methods: In 6 boys with severe hypospadias the urethral plate was divided and the septum between the corpora cavernosa was partially split with a ventral midline incision. This incision facilitates corporal rotation. Access to the dorsal aspect of the corpora cavernosa was achieved by dissecting Buck's fascia with its encased neurovascular bundles, so that the bundles in the area of chordee were completely elevated and preserved. Using artificial erection as a guide nonabsorbable sutures were placed in the area of maximal curvature from the dorsolateral aspect of 1 corpus cavernosum across the midline to the other side such that, as the knots were t...
Imaging properties and applications of slow-scan charge-coupled device cameras suitable for electron microscopy

Abstract Basic operation and important imaging characteristics of slow-scan charge-coupled device (CCD) cameras suitable for electron microscopy are reviewed. It is shown that these image detectors approach single electron detection, have high dynamic range, exceptional linearity, negligible distortion and excellent spectral transfer characteristics. A number of example applications illustrate the impact of slow-scan CCD cameras on quantitative image analysis, advanced multiple-image reconstruction methods and automated data collection.
Do Judges Make Regulatory Policy?: An Empirical Investigation of Chevron

In the last quarter-century, the Supreme Court has legitimated agency authority to interpret regulatory legislation, above all in Chevron U.S.A., Inc v Natural Resources Defense Council, Inc, the most-cited case in modern public law. Chevron recognizes that the resolution of statutory ambiguities often requires judgments of policy; its call for judicial deference to reasonable interpretations was widely expected to have eliminated the role of policy judgments in judicial review of agency interpretations of law. But this expectation has not been realized. On the Supreme Court, conservative justices vote to validate agency decisions less often than liberal justices. Moreover, the most conservative members of the Supreme Court show significantly increased validation of agency interpretations after President Bush succeeded President Clinton, and the least conservative members of the Court show significantly decreased validation rates in the same period. In a similar vein, the most conservative members of the Court are less likely to validate liberal agency interpretations than conservative ones and the least conservative members of the Court show the opposite pattern. Similar patterns can be found on federal appellate courts. In lower court decisions involving the EPA and the NLRB from 1990 to 2004, Republican appointees demonstrated a greater willingness to invalidate liberal agency decisions and those of Democratic administrations. These differences are greatly amplified when Republican appointees sit with two Republican appointees and when Democratic appointees sit with two Democratic appointees.
High-intensity-laser-electron scattering

In the field of an intense laser, photon-electron scattering becomes nonlinear when the oscillatory energy of the electron approaches its rest mass. The electron wave function is dressed by the field with a concomitant increase in the effective electron mass. When the photon energy in the electron rest frame is comparable to the electron rest mass, multiphoton Compton scattering occurs. When the photon energy is significantly lower than the electron rest mass, the electron acquires momentum from the photon field and emits harmonics. This paper reviews nonlinear photon-electron scattering processes and results from two recent experiments where they have been observed.
RAGE signaling by alveolar macrophages influences tobacco smoke-induced inflammation

Receptors for advanced glycation end-products (RAGE) are multiligand cell surface receptors of the immunoglobin family expressed by epithelium and macrophages, and expression increases following exposure to cigarette smoke extract (CSE). The present study sought to characterize the proinflammatory contributions of RAGE expressed by alveolar macrophages (AMs) following CSE exposure. Acute exposure of mice to CSE via nasal instillation revealed diminished bronchoalveolar lavage (BAL) cellularity and fewer AMs in RAGE knockout (KO) mice compared with controls. Primary AMs were obtained from BAL, exposed to CSE in vitro, and analyzed. CSE significantly increased RAGE expression by wild-type AMs. Employing ELISAs, wild-type AMs exposed to CSE had increased levels of active Ras, a small GTPase that perpetuates proinflammatory signaling. Conversely, RAGE KO AMs had less Ras activation compared with wild-type AMs after exposure to CSE. In RAGE KO AMs, assessment of p38 MAPK and NF-κB, important intracellular signaling intermediates induced during an inflammatory response, revealed that CSE-induced inflammation may occur in part via RAGE signaling. Lastly, quantitative RT-PCR revealed that the expression of proinflammatory cytokines including TNF-α and IL-1β were detectably decreased in RAGE KO AMs exposed to CSE compared with CSE-exposed wild-type AMs. These results reveal that primary AMs orchestrate CSE-induced inflammation, at least in part, via RAGE-mediated mechanisms.
A new reduced-complexity algorithm for multiple-symbol differential detection

Although multiple-symbol differential detection (MSDD) provides much better error performance than conventional differential detection, its complexity is much higher. We propose a reduced-complexity algorithm for MSDD. Our simulations show that the performance of the reduced complexity receiver is nearly identical to that of the original receiver, but with typical parameters, the number of phase sequences searched can be reduced by a factor of sixteen for QPSK to over four thousand for 16-PSK thereby leading to significant receiver complexity reduction.
Influence of the placenta in mammary gland growth.

Abstract The role of the placenta in promoting mammary growth was investigated by comparing the extent of development in rats either under full placental influence (pregnant), under maternal placental influence only (deciduoma), or under no placental influence (pseudopregnant). During the first ten days following mating there was little difference in glands of the three groups of rats. Early growth of the mammae was rapid, with good arborization and extensive lobulation in all three groups. During the subsequent period, however, only the pregnant group continued to show progressive growth. The deciduoma rats maintained an intermediate level, but the pseudopregnant group declined steadily in the 10–21-day post-mating period. Suspensions of rat placenta were not effective in causing greater mammary growth when injected into either the deciduoma or pseudopregnant groups. The results indicate a mammotropic influence of artificial deciduoma, suggesting a similar role for the decidual tissue of the maternal placenta during pregnancy.
THE EFFECTS OF p-HYDROXYPROPIOPHENONE ON THE THYROID GLAND OF EXPERIMENTAL ANIMALS

RECENT reports from France (1) indicate that p-hydroxypropioj phenone shows a marked ability to alleviate the signs and symptoms of thyrotoxicosis. Perrault has postulated that the beneficial effects of this drug are due to an inhibition of the production of the thyroid-stimulating hormone. Although confirmatory evidence of this observation is lacking, the results and conclusions which have been reported make a careful investigation of the physiologic action of this compound essential. In the course of our studies on the growth and function of the thyroid gland we have investigated the effect of p-hydroxypropiophenone on thyroid function in experimental animals. This report is the result of these studies. MATERIALS AND METHODS One hundred and twenty mature male rats of the Sprague-Dawley strain were used. In addition, 40 three-day-old chicks1 were also used. The experiments were set up in the following manner: Experiment I. Four groups (10 animals per group) of male rats were given a low-iodine diet (2). ...
Preliminary Design of a Dedicated Synchrotron Radiation Facility

An electron storage ring to be used solely as a synchrotron radiation source has been designed for a maximum energy of 1.5 GeV, expandable to 2 GeV, and a maximum current of 1 A, High field superconducting magnet wigglers to serve as hard radiation ports have been incorporated into the ring to make available a wide range of wavelengths for simultaneous experiments. The regular lattice consists of a series of small achromatic bends forming the arcs. The wiggler magnets are placed in low-s in the center of insertions separating these arcs. The arrangement minimizes the electron emittances and yields high source brightness. Other machine parameters are dictated by experimental requirements and apparatus as well as by cost constraints.