cssi/SciSciGPT-SciSciNet huggingface dataset:
Quadrature-Based Moment Model for Moderately Dense Polydisperse Gas-Particle Flows

A quadrature-based moment model is derived for moderately dense polydisperse gas-particle flows starting from the inelastic Boltzmann-Enskog kinetic equation including terms for particle acceleration (e.g., gravity and fluid drag). The derivation is carried out for the joint number density function, f(t,x,m,u), of particle mass and velocity, and thus, the model can describe the transport of polydisperse particles with size and density differences. The transport equations for the integer moments of the velocity distribution function are derived in exact form for all values of the coefficient of restitution for particle-particle collisions. For particular limiting cases, the moment model is shown to be consistent with hydrodynamic models for gas-particle flows. However, the moment model is more general than the hydrodynamic models because its derivation does not require that the particle Knudsen number (and Mach number) be small.
HUMAN-WHAT INTERACTION? UNDERSTANDING USER SOURCE ORIENTATION

Interaction with internet-connected computing devices involves interaction with many distinct agents or sources simultaneously. Hardware, operating systems, web browsers, networking devices, and se...
An Object-Oriented Online Tool for Solving Generalized Chemical Equilibrium Problems

Analysis of chemical equilibria is a topic covered in both undergraduate and graduate courses such as physical chemistry, chemical thermodynamics, and engineering thermodynamics. Manual calculation of problems that require a student to solve for species concentrations, partial pressures, or mole fractions usually involve the method of equilibrium constants. Exercises in homework assignments or in-class examinations are frequently limited to reactions that involve no more than four gas phase species as the resulting arithmetic required to solve for the unknown quantity becomes too cumbersome and prone to error. Students who invest the requisite time in manually solving complex equilibrium problems in homework assignments need a tool to verify their answer. A Java web application (“applet”) has been developed to assist engineering students who encounter general multiphase equilibrium problems involving many species. In addition to students, educators and professional researchers will benefit from a user friendly and free to use software package that can numerically compute equilibrium distributions for arbitrary reactions. The applet we present in this work can be used to analyze complex reactions involving twenty or more species and one such reaction, the combustion of isooctane and air, is presented as an example.Copyright © 2008 by ASME
Inhibitors of monoacylglycerol lipase as novel analgesics.

2-Arachidonoylglycerol (2-AG) is an endogenous cannabinoid (endocannabinoid) lipid whose functions remain poorly understood. Guindon and colleagues report the novel finding that exogenous application of 2-AG induces peripheral antinociceptive effects that are mediated, at least in part, by actions at peripheral cannabinoid CB2 receptors. URB602, a recently described inhibitor of monoacylglycerol lipase, an enzyme that catalyzes 2-AG hydrolysis in vivo, also induced peripheral antinociceptive effects and enhanced the actions of 2-AG. Peripheral analgesic mechanisms represent promising therapeutic targets for suppressing pain in the absence of unwanted central nervous system side-effects (e.g. psychoactivity) associated with activation of central CB1 receptors. The therapeutic potential of inhibitors of 2-AG deactivation for the treatment of inflammatory pain is discussed.
Decoding algorithms in pooling designs with inhibitors and error-tolerance

Pooling designs are used in DNA library screening to efficiently distinguish positive from negative clones, which is fundamental for studying gene functions and many other biological applications. One challenge is to design decoding algorithms for determining whether a clone is positive based on the test outcomes and a binary matrix representing the pools. This is more difficult in practice due to errors in biological experiments. More challenging still is a third category of clones called 'inhibitors' whose effect is to neutralise positives. We present a novel decoding algorithm identifying all positive clones in the presence of inhibitors and experimental errors.
Pharmacokinetics of 2,4,5-T in mice as a function of dose and gestational status.

Abstract A pharmacokinetic study was conducted in CD-1 mice with the herbicide 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) as a function of dose (15, 30, 60, and 90 mg/kg, iv) and gestational status (nonpregnant, day 6, 10, 13, and 17 of gestation, and postpartum). Analysis for 2,4,5-T and its metabolites was based on an electron-capture gas-liquid chromatographic method. Pharmacokinetic simulation of the blood, urine, and feces data from each mouse was performed on an analog-digital hybrid computer system based on a two-compartment model with parallel, first-order elimination kinetics. Data analysis demonstrated dose-independent kinetics for most pharmacokinetic parameters but a gestational status-dependence. There was a tendency, as indicated by an increase in the biological half-life and AUC and decrease in clearance and total percent recovery, for pregnant animals to eliminate 2,4,5-T more slowly as gestation progressed, resulting in potentially increasing fetal exposure during the later states of pregnancy.
Mycobacterium tuberculosis infection in immunocompetent children

Objective. The purpose of this paper is to present our experi- ence with Mycobacterium tubercu- losis infections in immunocompe- tent children. Subjects and methods. Radiology, pathology, microbiology, and dis- charge records at two institutions identified the study population. Children who were immunocom- promised and those with a positive skin test and no radiological or clin- ical evidence of active infection were excluded. Active mycobacte- rial infection was defined by a posi- tive culture, biopsy, or a reactive purified protein-derivative skin test (PPD) with an appropriate clinical presentation and response to ther- apy and/or known exposure to an adult with active tuberculosis. Results. There were 22 children in whom Mycobacterium tuberculosis (MTb) was identified. Fourteen of the patients with MTb were 5 years of age or younger. The most com- mon sites of radiological involve- ment were the lungs (15 cases) and the hila (eight cases). Four patients had evidence of extrathoracic MTb infection. Three cases of miliary tu- berculosis were identified, all in children less than 9 months of age. Conclusion. Although pulmonary and/or hilar disease remains the most common radiological presen- tation of childhood tuberculosis, the radiologist must be aware of the many radiological presentations of childhood Mycobacterium tubercu- losis infection, and should have a high index of suspicion with the in- creasing incidence in both normal and immunocompromise d children.
The impact of driver alcohol use on crash severity: A crash specific analysis

This study uses a crash specific data set that is supplemented with location based socioeconomic data to estimate the impact of driver alcohol use on average crash severity. Logit estimates indicate that crashes in which the at-fault drivers had been drinking are more likely to result in a severe injury or death than are crashes caused by sober drivers. Ordered logit estimates indicate that at-fault driver alcohol use increases the expected highest degree of injury resulting from a crash, and Tobit estimates indicate that the number of injuries or deaths per crash increase an average of 0.71 when the at-fault driver has been drinking. Moreover, at-fault driver alcohol use worsens the severity of crashes relative to not-at-fault parties. Collectively, these results indicate that at-fault drinking drivers are involved in more violent crashes and produce more serious injuries to not-at-fault parties than at-fault sober drivers.
Prevalence of illicit use and abuse of prescription stimulants, alcohol, and other drugs among college students: relationship with age at initiation of prescription stimulants.

During the past decade, the illicit use of prescription drugs, including prescription stimulants, has become the second most common form of illicit drug use among college students in the United States.1 National data from 2003 showed that college students aged 19–22 years were more likely to report illicit use of Ritalin (Novartis Pharmaceuticals Corp., East Hanover, NJ) than the same age population not enrolled in college.1 To further highlight this problem, associations have been found between the illicit use of prescription stimulants and higher rates of cigarette smoking, heavy episodic drinking, marijuana use, and cocaine use among adolescents, young adults,2, 3 and college students in the United States.4–7 An association has also been found between the illicit use of prescription stimulants and the age at which an individual reports the initiation of prescription stimulants. For example, results of our previous study found that initiation of prescription stimulant drugs after elementary school is associated with increased risk of illicit use of prescription stimulants during college.8 However, research is limited regarding the relationship between initiation of prescription stimulants among specific age groups and use and abuse of alcohol and other drugs. Our primary objective was to investigate illicit use and abuse of prescription stimulants, alcohol, and other drugs based on the age of initiation of prescription stimulants among an undergraduate college student sample in the United States. This study builds on our earlier work8 by assessing the effect of age at initiation of prescription stimulants on substance abuse as indicated by brief screening instruments and coingestion of alcohol and illicit prescription stimulants.
A case study of employment case management with chronically unemployed methadone maintained clients

Employment interventions implemented in drug treatment programs have been marginally successful, but few interventions have been found to address the needs of chronically unemployed clients. Employment case management (ECM) is a comprehensive employment intervention strategy designed to motivate chronically unemployed persons to engage in work, assist in job placement, and provide post employment support through workforce integration, while maintaining progress in drug treatment. This clinical case study reports on a convenience sample of 10 chronically unemployed methadone maintained clients who voluntarily enrolled in the ECM project. Clients received individual ECM services for a period of 26 weeks. Clients were assessed at two- and eight-month follow-up intervals. Nine of the 10 clients were employed at the two-month follow-up assessment and six maintained employment at the eight-month follow-up. Moreover, three clients were able to successfully transition from welfare to competitive private sector employment. Preliminary data suggest that ECM may be an effective intervention strategy to help chronically unemployed methadone clients obtain and maintain employment. Qualitatively, clients reported that post employment intervention services such as motivational counseling, problem solving, and employer advocacy helped sustain employment.
Influence of thyroid on formation of myelin lipids.

—The formation of lipids found primarily in the myelin sheath was investigated in rats made hypothyroid, at birth. A marked reduction in cerebroside, sulphatide, and cholesterol of brains was found in 18-day-old hypothyroid animals. These lipids were also reduced, although to a lesser degree, in 30-day-old ex-hypothyroid animals allowed to return to the euthyroid state at age 18 days. The onset of formation of sulphatide in vivo was delayed in the hypothyroid animals. Sulphatide formation reached a peak at a later time and was greatly reduced in comparison to control animals. The activity in vitro of galactolipid sulphotransferase, which forms sulphatide from cerebroside and PAPS, was reduced only when exogenous PAPS was not added to the assay medium. This finding suggests a defect in the formation of PAPS from ATP and sulphate in the hypothyroid brain. In addition, T3 (tri-iodothyronine) had a stimulatory effect in vivo of formation brain sulphatide when administered to rats during the first 5 days of life.
Quasi-Linear Viscoelastic Properties of Normal Articular Cartilage

A combined experimental and analytical approach was used to determine the history-dependent viscoelastic properties of normal articular cartilage in tension. Specimens along the surface split line direction, taken from the middle zone of articular cartilage were subjected to relaxation and cyclic tests. A quasi-linear viscoelastic theory proposed by Fung [31] was used in combination with the experimental results to determine the nonlinear viscoelastic properties and the elastic stress-strain relationship of normal articular cartilage.
Conformational differences among mono- and oligosaccharide fragments of the O-specific polysaccharides of Vibrio cholerae O1 revealed by circular dichroism

The circular dichroism (CD) of synthetic mono- and oligosaccharides that represent the terminal, non-reducing group of O-antigens of Vibrio cholerae O1 from the subtypes Ogawa and Inaba was measured in various solvents. We found differences in the CD of the monosaccharides of these subtypes that decrease with increasing chain lengths of the oligosaccharides. The differences can be explained by different orientations of the N-acyl side chain of the terminal monosaccharides. The linear relationship of ellipticity versus the number of residues in an oligosaccharide chain follows the principle of optical superposition. This, together with a similar contribution by internal units to the overall ellipticity, suggests an identical, regular conformation of oligosaccharide fragments of both Ogawa and Inaba series.
Recent advances of discrete coordination complexes and coordination polymers in drug delivery

Abstract Coordination complexes (including discrete coordination complexes and coordination polymers) have demonstrated excellent performance in drug delivery. This review outlines recent advances of discrete coordination complexes, bulk coordination polymers, and nanoscale/microscale coordination polymers in drug delivery. Specifically, rationale and mechanism of coordination complexes in drug delivery are summarized in this contribution. In this review, we discuss applications of these coordination species in drug delivery from perspectives in chemistry and pharmaceutical sciences, and an outlook of these coordination species of interest in drug delivery will also be proposed.
Decomposition-based exact algorithms for risk-constrained traveling salesman problems with discrete random arc costs

Recently increasing attentions have been given to uncertainty handling in network optimization research. Along this trend, this paper discusses traveling salesman problem with discrete random arc costs while incorporating risk constraints. Minimizing expected total cost might not be enough because total costs of some realizations of the random arc costs might exceed the resource limit. To this respect, this paper presents a model of the traveling salesman problem that incorporates risk constraints based on Conditional Value at Risk to evaluate those worst-cost scenarios. Exact solution methods are developed and applied on the risk-constrained traveling salesman problem. Numerical experiments are conducted, and the results show the ability of the proposed methods in reducing the computational complexity.
The critical role of climate and saprolite weathering in landscape evolution

Landscapes evolve in response to external forces, such as tectonics and climate, that influence surface processes of erosion and weathering. Internal feedbacks between erosion and weathering also play an integral role in regulating the landscapes response. Our understanding of these internal and external feedbacks is limited to a handful of field-based studies, only a few of which have explicitly examined saprolite weathering. Here, we report rates of erosion and weathering in saprolite and soil to quantify how climate influences denudation, by focusing on an elevation transect in the western Sierra Nevada Mountains, California. We use an adapted mass balance approach and couple soil-production rates from the cosmogenic radionuclide (CRN) 10Be with zirconium concentrations in rock, saprolite and soil. Our approach includes deep saprolite weathering and suggests that previous studies may have underestimated denudation rates across similar landscapes. Along the studied climate gradient, chemical weathering rates peak at middle elevations (1200–2000 m), averaging 112·3 ± 9·7 t km–2 y–1 compared to high and low elevation sites (46·8 ± 5·2 t km−2 y−1). Measured weathering rates follow similar patterns with climate as those of predicted silica fluxes, modeled using an Arrhenius temperature relationship and a linear relationship between flux and precipitation. Furthermore, chemical weathering and erosion are tightly correlated across our sites, and physical erosion rates increase with both saprolite weathering rates and intensity. Unexpectedly, saprolite and soil weathering intensities are inversely related, such that more weathered saprolites are overlain by weakly weathered soils. These data quantify exciting links between climate, weathering and erosion, and together suggest that climate controls chemical weathering via temperature and moisture control on chemical reaction rates. Our results also suggest that saprolite weathering reduces bedrock coherence, leading to faster rates of soil transport that, in turn, decrease material residence times in the soil column and limit soil weathering. Copyright © 2009 John Wiley & Sons, Ltd.
Phanerozoic trends in background extinction: Consequence of an aging fauna

Changes in the rate of background extinction are analyzed as a function of changing age distributions of families. Declining background-extinction rates have previously been attributed to evolution at the family or community level. It is demonstrated, however, that if the probability of extinction for a family decreases through its own history, then overall changes in background-extinction rate are a function of a changing familial age distribution. In geologic stages where there is a preponderance of young families, extinction rates can be predicted to be higher than in times where there is a plethora of older families. In addition, it is demonstrated that a difference exists between the age distributions of families that become extinct in background- and mass-extinction intervals.
The maxillary denture: its palatal relief and posterior palatal seal.

Improper delineation of areas for palatal relief and posterior palatal seal in the construction of a prosthesis may cause inflammatory, necrotic, and premalignant tissue changes in the patient.
The derivation of a thick and thin plate formulation without ad hoc assumptions

For the plate formulation considered in this paper, appropriate three-dimensional elasticity solution representations for isotropic materials are constructed. No a priori assumptions for stress or displacement distributions over the thickness of the plate are made. The strategy used in the derivation is to separate functions of the thickness variable z from functions of the coordinates x and y lying in the midplane of the plate. Real and complex 3-dimensional elasticity solution representations are used to obtain three types of functions of the coordinates x, y and the corresponding differential equations. The separation of the functions of the thickness coordinate can be done by separately considering homogeneous and nonhomogeneous boundary conditions on the upper and lower faces of the plate. One type of the plate solutions derived involves polynomials of the thickness coordinate z. The other two solution forms contain trigonometric and hyperbolic functions of z, respectively. Both bending and stretching (or in-plane) solutions are included in the derivation.
Intrinsic Histone-DNA Interactions and Low Nucleosome Density Are Important for Preferential Accessibility of Promoter Regions in Yeast

In yeast cells, preferential accessibility of the HIS3-PET56 promoter region is determined by a general property of the DNA sequence, not by defined sequence elements. In vivo, this region is largely devoid of nucleosomes, and accessibility is directly related to reduced histone density. The HIS3-PET56 and DED1 promoter regions associate poorly with histones in vitro, indicating that intrinsic nucleosome stability is a major determinant of preferential accessibility. Specific and genome-wide analyses indicate that low nucleosome density is a very common feature of yeast promoter regions that correlates poorly with transcriptional activation. Thus, the yeast genome is organized into structurally distinct promoter and nonpromoter regions whose DNA sequences inherently differ with respect to nucleosome formation. This organization ensures that transcription factors bind preferentially to appropriate sites in promoters, rather than to the excess of irrelevant sites in nonpromoter regions.
Retarded reduction of cytochrome b5 following the aerobic-anaerobic transition of intact rat liver mitochondria

Abstract 1. 1. We measured the absorbance at 560–575 nm, using a dual wavelength spectrophotometer, of a suspension of rat liver mitochondria during depletion of dissolved oxygen. The absorbance, predominantly due to the cytochromes b and b5, underwent a transition consisting of two rapid phases of increase separated in time by a slower phase of increase. 2. 2. The retarded phase of absorbance increase disappeared when NADH was added, and the total amplitude of absorbance increase in the aerobic-anaerobic transition was reduced by an amount corresponding to the amplitude of the retarded phase of absorbance increase. This indicates that the first rapid phase of absorbance increase is due to the reduction of cytochrome b, and the retarded phase is due to the reduction of cytochrome b5. 3. 3. Liquid nitrogen temperature difference spectra of two samples with and without added NADH identified the pigment undergoing the retarded reduction as mitochondrial cytochrome b5. The concentration of this mitochondrial cytochrome is 0.4 moles per mole of cytochrome c oxidase. 4. 4. The retarded termination of the steady state of oxidation of mitochondrial cytochrom b5 indicates the presence of a pool of oxidizing equivalents.
Finite-Element Analysis of Current-Induced Thermal Stress in a Conducting Sphere

Understanding the electrothermal-mechanical behavior of electronic interconnects is of practical importance in improving the structural reliability of electronic devices. In this work, we use the finite-element method to analyze the Joule-heating-induced thermomechanical deformation of a metallic sphere that is sandwiched between two rigid plates. The deformation behavior of the sphere is elastic–perfectly plastic with Young’s modulus and yield stress decreasing with temperature. The mechanical stresses created by Joule heating are found to depend on the thermal and mechanical contact conditions between the sphere and the plates. The temperature rise in the sphere for the diathermal condition between the sphere and the plates deviates from the square relation between Joule heat and electric current, due to the temperature dependence of the electrothermal properties of the material. For large electric currents, the simulations reveal the decrease of von Mises stress near the contact interfaces, which suggests that current-induced structural damage will likely occur near the contact interfaces.
A Whole-Hearted Effort to Get It Half Right: Predicting the Future of Communication Technology Scholarship

As I consider communication technology research —where it has been and where it is going —I regularly think back to a response I wrote for my comprehensive exams as a doctoral student 15 years ago. In an essay to defend the relevance of communication technology as an area of study, I somewhat boldly predicted that communication technology would never be a major subfield itself because experts across a wide range of more traditional subfields would end up studying the topic in each of their specialty areas. As with most things, I was only about half right. Indeed, one does not have to look very far to see the importance of communication technologies when it comes to research throughout the communication discipline. However, I missed the mark in anticipating the amazing growth of communication technology scholarship as its own unique realm of study in Communication and related fields. Thanks to growing published scholarship, new research and teaching jobs, and rising professional memberships related to communication and technology, this area has begun to successfully carve out its own identity as distinct and complementary to other subfields in our discipline. Despite my admittedly poor record at attempting to predict the future—and the even more difficult endeavor to actually shape it —I think such efforts are necessary to stimulate thinking and set priorities. I would like to suggest three directions for communication and technology research —but given that limited ability to predict the future accurately only about half the time, I will actually provide six future directions in hopes that three might hit the mark. Indeed, these are what I see as desirable directions for where we need to go as much as prophetic predictions about where we’re headed. Let me briefly introduce each idea here.
Use of extrapolation on wave expansions to force the satisfaction of the Rayleigh hypothesis

An extrapolation method is shown to force the convergence of a diverging wave expansion. This wave expansion will then satisfy the Rayleigh hypothesis over a much broader region. Only a single wave expansion then becomes necessary for field solutions in a particular region, making methods such as analytic continuation unnecessary.
Joseph Conrad Criticism

Article This essay is a brief survey of the history of commentary on the life and works of Joseph Conrad. Beginning with some of the early shorter and extended commentaries that appeared during the second decade of the twentieth century and ending with some of the most recent commentaries, this overview is intended to give the reader a clear idea of the significant issues that have arisen in the study of Conrad’s life and works. During the course of this essay, dominant movements will appear in Conrad studies: biographical/historical studies appearing during the 1920s and 1930s, psychological studies appearing during the 1950s and 1960s, poststructural and postcolonial studies appearing during the 1980s and 1990s, and gender studies appearing more recently. Furthermore, important individual commentaries will also be considered, so that the reader will have a good idea of where to go to investigate further various issues regarding Conrad’s life and works.
HIV risk behaviors in African‐American drug injector networks: implications of injection‐partner mixing and partnership characteristics

Aims We explore the mechanisms by which ‘partnership-level’ variables––the mix of characteristics of individuals who inject drugs together––affect the incidence of HIV risk behaviors, including receptive syringe sharing, and facilitate or impede the spread of HIV. Design We apply multivariate analysis techniques to data on injection partnerships (pairs of individuals who inject drugs together) collected using a network sample of 401 African-American IDUs in Washington, DC. Findings Drug injectors tended to select injection partners of the same gender and similar age, but risk behaviors were most common in partnerships between individuals who are dissimilar in both gender and age. Partners who had a sexual relationship, injected drugs frequently together, smoked crack-cocaine regularly, injected speedball (heroin mixed with cocaine) regularly and/or had close social ties were more likely to engage in risky injection practices than otherwise similar partners. These factors account largely for the association between the gender-age mix of the partnership and injection risk behavior. Conclusions Among African-American IDUs in Washington DC, partnership-level variables appear critical in the transmission of HIV.
Trust and Influence in Combat: An Interdependence Model

Two studies tested an interdependence model of trust development and the links between trust and influence in the in extremis environment of combat, and a noncombat replication. Structural equation modeling was used to test the model. Results from both studies suggested that a modified interdependence model provided a plausible explanation for how leaders may earn subordinate trust, through fostering the establishment of cooperative interdependence and being perceived as credible. Credibility was demonstrated through both competence and good character, and organizational structures that were in place contributed to trust by encouraging leaders to behave cooperatively toward group members. Most importantly, the level of trust subordinates had in their leaders determined the amount of leader influence subordinates accepted. Although leadership processes may be common across diverse situations, perhaps the most crucial setting in which to explore these processes is the combat zone. Beyond taking coercive measures, what is it that enables leaders, be they superiors or peers, to influence subordinates to risk injury or death to achieve the organization’s objectives in combat? We propose that the mechanism is trust; not just trust in the leader, but mutual trust between leaders and subordinates. Trust is no doubt a critical mechanism in all relationships: interpersonal, educational, and organizational. However, it seems critical in the military, particularly in a combat situation. Former senior military leaders and researchers have proposed that there will be neither leader nor unit effectiveness in combat in the absence of mutual trust between leaders and subordinates, and between the soldiers themselves. Without such trust, orders may not be fully obeyed, nor will the interests of the unit be placed above individual interests (Collins & Jacobs, 2002; Ulmer, 1989).
The Rich Get Richer The Attenuation of Targeting Effects of the Community Development Block Grant Program

This article discusses how the Community Development Block grant targeting policy adopted in 1977 has changed to the disadvantage of needier communities as the result of continuing demographic chan...
Two-Dimensional Router for Double Layer Layout

A heuristic algorithm for two dimensional routing utilizing two distinct layers is presented. It is assumed that all terminals are on the boundary of a rectilinear routing region with or without initial routes present. The router produces a Manhattan-style routing collapsed into one layer. Another program decides the layering, however, it is not described here. By default, when the layering program is not used, vertical segments of routes are placed on one layer, horizontal on the other.
Transport rates of a class of two-dimensional maps and flows

Abstract A method is developed for estimating the transport rates of phase space areas for a class of two-dimensional diffeomorphisms and flows. The class of diffeomorphisms we considered are defined by the topological structure of their stable and unstable manifolds, and hence are universal. We show how to estimate the transport rates for a class of diffeomorphisms found by Easton and for an extension of this class of diffeomorphisms which is found via a “perturbation” of the topology of the stable and unstable manifolds. This is done by introducing symbolic dynamics and transfer matrices which in turn relate transport phenomena in phase space to Markov processes in a precise manner. In addition to the transport rates, we use the transfer matrices to obtain estimates for the topological entropy, averaged stretching rates, and the elongation rate of the unstable manifold. The flows we consider are two-dimensional, time-periodic flows which can be reduced via Poincare section to the extended family of maps. We develop an analytical method, based on Chirikov's Whisker map, to classify a given flow according to the structure of its manifolds in its Poincare section. This allows the techniques developed here for maps to be directly applied to time-periodic flows.
A Determination by the Constant Deflection Method of the Value of the Coefficient of Slip for Rough and for Smooth Surfaces in Air

Coefficient of slip for rough and smooth surfaces in air, determined by the constant deflection method.---The apparent coefficient of viscosity measured by this exceptionally precise method does not come out constant for the lower pressures unless correction is made for the slip at the surfaces. The relation ${{\ensuremath{\eta}}_{p}}^{\ensuremath{'}}(1+k{\ensuremath{\zeta}}_{p})=\ensuremath{\eta}$ = constant, between ${{\ensuremath{\eta}}_{p}}^{\ensuremath{'}}$, the apparent viscosity coefficient, and ${\ensuremath{\zeta}}_{p}$, the coefficient of slip, enables ${\ensuremath{\zeta}}_{p}$ to be determined from measurements of ${{\ensuremath{\eta}}_{p}}^{\ensuremath{'}}$ at pressures of 0.2 mm or lower. The apparatus included a vacuum-tight chamber inside which a cylinder of radius 5.341 cm was suspended by a steel wire concentric with a cylinder of radius 6.063 cm which could be rotated at a constant slow rate so as to cause a steady deflection of the inner cylinder. The accuracy of this method of measuring ${{\ensuremath{\eta}}_{p}}^{\ensuremath{'}}$ is so great that the values of ${\ensuremath{\zeta}}_{76}=\frac{{\ensuremath{\zeta}}_{p}p}{76}$ all lie within \ifmmode\pm\else\textpm\fi{} 4 per cent of the mean. The chief difficulty was in keeping the air pure because of the gradual evolution of gas, probably hydrogen, inside the apparatus; but by taking observations only shortly after evacuation this effect was avoided. For brass surfaces, $\ensuremath{\zeta}$, reduced to 23\ifmmode^\circ\else\textdegree\fi{} and 76 cm, came out 66.15 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}7}$ which is practically the theoretical minimum deduced by Millikan for a completely diffusing surface, 65.9 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}7}$. For surfaces coated with shellac, the coefficient was found to be 97 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}7}$ for a fresh surface, in agreement with the value obtained by Lee from droplet measurements, but it decreased steadily with time, presumably because of a roughening due to oxidation, falling in two months to within 3 per cent of the theoretical minimum. The early part of this work was done in collaboration with E. L. Harrington.Coefficient of viscosity of air at 0.1 mm is the same as at atmospheric pressure when correction is made for the slip effect. The constancy of the values obtained for $\ensuremath{\zeta}$ provides new evidence that the coefficient is independent of the pressure.
Path optimization and control of a shape memory alloy actuated catheter for endocardial radiofrequency ablation

This paper introduces a real-time path optimization and control strategy for shape memory alloy (SMA) actuated cardiac ablation catheters, potentially enabling the creation of more precise lesions with reduced procedure times and improved patient outcomes. Catheter tip locations and orientations are optimized using parallel genetic algorithms to produce continuous ablation paths with near normal tissue contact through physician-specified points. A nonlinear multivariable control strategy is presented to compensate for SMA hysteresis, bandwidth limitations, and coupling between system inputs. Simulated and experimental results demonstrate efficient generation of ablation paths and optimal reference trajectories. Closed-loop control of the SMA-actuated catheter along optimized ablation paths is validated experimentally. A path optimization and control strategy for shape memory alloy actuated cardiac ablation catheters is presented.Catheter tip locations and orientations are optimized using parallel genetic algorithms.Closed-loop control of the SMA-actuated catheter along optimized paths is validated experimentally.
Supersymmetric dark matter in the harsh light of the Large Hadron Collider

I review the status of the model of dark matter as the neutralino of supersymmetry in the light of constraints on supersymmetry given by the 7- to 8-TeV data from the Large Hadron Collider (LHC).
Use of Urea by Early Postpartum Holstein Cows

Thirty-nine lactating Holstein cows were fed high-energy complete rations ad libitum with crude protein: 1) 11.7% (negative control); 2) 13.9% (1% urea); 3) 16.6% (1% urea); or 4) 16.6% (positive control) in a continuous 12-wk study beginning at wk 5 postpartum. Milk production of 27.7, 31.8, 34.0, and 30.4 kg/day showed the use of urea nitrogen by groups 2 and probably 3. Two digestion-nitrogen balance trials with each cow also provided evidence that urea nitrogen was used for milk secretion. Energy digestibility averaged 59.4, 64.2, 65.4, and 65.8; and lower for the negative control diet. Nitrogen solubility in the diets was 28, 36, 32, and 21%, which reflects the objective of selecting ingredients with low nitrogen solubility for use in urea diets. Concentrations of ammonia nitrogen before and after feeding were 1.1, 3.3, 3.5, 4.2, and 2.2, 11.2, 11.9, and 9.3 mg/100 ml of rumen fluid. The prefeeding amounts were probably too low for maximum microbial growth. Urea-nitrogen concentrations in plasma were 8.65, 10.32, 18.00, and 17.03 mg/100 ml. These results lend support to the postulate that lactating cows in early lactation can use urea nitrogen when high-energy complete rations with ingredients of low nitrogen solubility are fed ad libitum.
The Mayor's Role in School Desegregation Implementation

Successful, or at least nonviolent, strategy for school desegregation depends upon the city's social and political structure.
Immunosuppressive medications during pregnancy and lactation in women with autoimmune diseases.

Most autoimmune diseases predominantly affect females. Many of these diseases occur in women who have the potential to become pregnant or wish to plan a pregnancy. The potential for fetotoxic effects of immunosuppressive medications that are commonly used to treat systemic autoimmune diseases must be weighed against the need for control of disease activity during pregnancy and the postpartum period, since active disease can be an independent risk factor for adverse pregnancy outcomes. Although far from conclusive, most data concerning the safety of medications for use during pregnancy come from case series and observational studies. It is often necessary to continue treating patients throughout pregnancy and lactation in order to control the activity of the underlying disease. The aim of this paper is to review the evidence regarding the safety of the most commonly used medications in rheumatic disease during pregnancy or lactation and to enable practitioners and patients to make informed decisions regard...
THE INTERCONVERSION OF ESTRONE AND ESTRADIOLIN THE PERFUSED HUMAN PLACENTA12

THE human placenta is a relatively abundant source of estrogens. The determination of the concentration of estrone, estradiol and estriol in that organ has been the subject of several investigations (Huffman, Thayer and Doisy, 1940; Mitchell, 1952; Diczfalusy, 1953). More recently, the metabolism of estrogens in the placenta has also been studied. Peaiiman, Cerceo and Thomas (1954) using homogenates and Ryan and Engel (1953) using slices demonstrated the capacity of the human placenta to convert estradiol to estrone. The latter authors further found that under their experimental conditions there was no conversion of estrone to estradiol by term placenta and only minimal conversion by early placenta. The present investigation was undertaken to examine the question of interconversion of estrone and estradiol in the perfused human placenta. The use of radioactive estrogens made it possible to work at very low concentrations.
Characterization of the Inorganic Constituents in Coal

Anticipating the environmental effects of utilization or disposal of coal combustion and conversion by-products requires proper characterization of the inorganic constituents in coal. Inorganic constituents include minerals as well as the organically associated inorganic elements. Characterization of these constituents should not be limited to the types and abundances of the minerals and elements, but should also include their modes of occurrence (Table I and Figures 1–4). Information on modes of occurrence should include the textural relationships of the minerals and the chemical form of the elements (i.e. organic/inorganic associations). This will enable us to predict better how the inorganic constituents will behave upon cleaning, combustion, conversion, or leaching of the coal. For example, chalocophile elements (As, Bi, Cd, Cu, Hg, Pb, Se, Sb, Tl, Zn) associated with secondary cleat (vertical breaks in the coal) or with vein filling sulfides will likely be removed during coal cleaning. In contrast, these elements, when associated with dispersed accessory sulfides and selenides [sphalerite (ZnS), clausthalite (PbSe), chalcopyrite (CuFeS2), galena (PbS)] are commonly concentrated in the cleaned coal. Calcium present in coal as a carbonate would respond to technological processes in a different way than calcium present in organic association or as calcium sulfate, phosphate or silicate. Characterization of the minerals is complicated by: 1) their small size (mean grain size is less than 5 micrometers); 2) intimate association of the organic and inorganic phases; 3) complex and variable mineral assemblages; 4) rare but environmentally important accessory mineral phases; 5) modifications created by handling and analysis. Characterization of the elements is complicated by: 1) ppm-level concentrations of environmentally and technologically important elements; 2) multiplicity of chemical forms; 3) volatility of elements such as Hg, Na, B, Se; 4) specificity of analytical techniques. These complications can, in part, be overcome by proper sample preparation and by appropriate use of modern analytical tools. No single analytical tool is sufficient for most characterization problems. Rather, solutions to these problems require selecting the right combination of sample preparation techniques (e.g. leaching, polishing, ashing, density separation) and analytical tools. Information on the analytical tools is presented in Tables II and III. Through careful characterization of the inorganic constituents in coal we can properly evaluate their role in ash formation. More detailed discussion of these topics can be found in references 1–8.
Pathways of Antigen Processing

T cell recognition of antigen-presenting cells depends on their expression of a spectrum of peptides bound to major histocompatibility complex class I (MHC-I) and class II (MHC-II) molecules. Conversion of antigens from pathogens or transformed cells into MHC-I- and MHC-II-bound peptides is critical for mounting protective T cell responses, and similar processing of self proteins is necessary to establish and maintain tolerance. Cells use a variety of mechanisms to acquire protein antigens, from translation in the cytosol to variations on the theme of endocytosis, and to degrade them once acquired. In this review, we highlight the aspects of MHC-I and MHC-II biosynthesis and assembly that have evolved to intersect these pathways and sample the peptides that are produced.
Correlation and Fourier analysis in real time, inexpensively

An economical means of constructing a Fourier analyzer utgizing polarity correlation is described. Only one sinusoidal Oscillator and its quadrature function are required, but one clock is needed for each pair of cosine and sine coefficients. Included are analyses of the convergence time for a given fractional error probability and of the error variance for RC averaging.
Portraits of Religion in Introductory American Government Textbooks: Images of Tolerance or Intolerance

The link between religion and political tolerance in the United States, which has focused predominantly on Christianity, is replete with unfavorable images. Often, religious adherents (largely Evangelicals or the Christian right) are characterized as uneducated, poor, and white, suggesting that members of these groups may act in an intolerant manner. Our objective is to examine how different religious groups and individuals of faith pictorially appear within introductory American government textbooks. Are they visually portrayed as politically tolerant or intolerant? Are the images of individuals and groups presented as exercising rights to speech, assembly, and petition or as a threat to others' civil rights? What general themes or issues surrounding the visual representation of religion and politics are emphasized? We find that the textbook depictions show religious individuals in a tolerant light (just about as likely to be the victims, as the perpetrators, of intolerance), educated, and not poor. Alth...
Historical Comparisons: Testing Psychological Hypotheses with Cross-Era Data

Abstract Cross-era research, an approach which involves developing and testing social science hypotheses in terms of historical time-series data, is first discussed as regards its relationship to other comparative research approaches. Some examples of cross-era research in psychology are described. Special problems that arise in cross-era research, and proposed methods of coping with them, are discussed as regards each of the three successive phases of research: creative hypothesis formation problems; difficulties that arise in the hypothesis-testing phase; and problems that emerge during the phase of communicating and utilizing the findings.
The long-term outcome in men with exstrophy/epispadias: sexual function and social integration.

AbstractPurpose: We evaluated the long-term outcome of social integration and sexual function in 29 men with bladder exstrophy and epispadias.Materials and Methods: Four men with epispadias and 25 with bladder exstrophy were available for long-term followup. Patients were interviewed by telephone regarding sexual history and social integration. Semen analyses were obtained in 8 cases.Results: Patient assessment of genital appearance was good or fair in 71 percent. Potency was present in all patients, and erections were straight in 66 percent and curved in 34 percent with no curvature so severe as to prevent sexual intercourse. Semen analysis showed a normal sperm count in 63 percent of the men and no azoospermia. Social integration was satisfactory: 100 percent of the men attended high school, 55 percent have a college education and all who are not attending school have full-time jobs.Conclusions: Our long-term review demonstrates that despite what appears to be a significant sexual handicap, patients wit...
Too much short chain fatty acids cause neonatal necrotizing enterocolitis

Nenatal necrotizing enterocolitis (NEC) is a disease mainly affects premature infants. It is well known that prematurity, enteral formula feeding, and bacterial colonization are three major risk factors for NEC. Acetic acid, propionic acid and butyric acid are short chain fatty acids (SCFAs), which are produced mainly in the colon by bacterial fermentation of undigested carbohydrates. Although luminal production of modest quantities of SCFAs is essential for normal colonic mucosal function, excessive production/accumulation of SCFAs may arise in premature infants due to increased luminal carbohydrates malabsorption and poor gastrointestinal motility, and may have deleterious effects on mucosal integrity. Therefore, it is proposed that too much luminal short chain fatty acids cause neonatal NEC.