cssi/SciSciGPT-SciSciNet huggingface dataset:
Field modeling with sampled distances

Traditional mesh-based approaches to the modeling and analysis of physical fields within geometric models require some form of topological reconstruction and conversion in the mesh generation process. Such manipulations tend to be tedious and error-prone manual processes that are not easily automated. We show that most field problems may be solved directly by using approximate distance fields computed from designed or sampled geometric data, thus avoiding many of the difficult reconstruction and meshing problems. With distances we can model fields that satisfy boundary conditions while approximating the governing differential equations to arbitrary precision. Because the method is based on sampling, it provides natural control for multi-resolution both in geometric detail of the domain and in accuracy of the computed physical field. We demonstrate the field modeling capability with several heat transfer applications, including a typical transient problem and a 'scan and solve' approach to the simulation of a physical field in a real-world artifact.
Seismic imaging of the geothermal field at Krafla, Iceland using shear-wave splitting

Abstract Shear-wave splitting is emerging as a useful exploration method for geothermal reservoirs as it can detect the geometry of the fracture system, the intensity of cracking and possibly, changes in fluid pressure within the reservoir. The method is based on the analyses of polarizations and time delays of shear-waves that have been distorted by the anisotropy of the medium through which the seismic waves have propagated. Observations of shear-wave splitting within the Krafla–Leirhnukur geothermal field, Iceland, using a 20-station 3-component portable seismic array have provided evidence for at least two major crack systems of microfractures, oriented approximately N–S and E–W. Located microearthquakes align roughly along the E–W direction of the geothermal field, with shallow focal depths mostly around the injection well, probably related to the ongoing injection. This unexpected direction is however consistent with results from a simultaneous MT (magnetotelluric) survey.
Nuclear Radio-Frequency Spectra of a Series of Tetrahedral Molecules

The molecular-beam magnetic-resonance method has been applied to a series of tetrahedral molecules. In each case, the radio-frequency spectrum was observed which corresponds to the reorientation of the total nuclear spin with respect to a large external magnetic field. In order to analyze these spectra, the energy levels of the complete spinrotation interaction and the direct dipole-dipole interaction have been calculated to first order in high-field perturbation theory by applying the recent group-theoretical treatment of Yi, Ozier, and Anderson. On the basis of these energy levels, the theoretical spectrum for each molecule has been constructed on a high-speed digital computer. By fitting this theoretical spectrum to the data, it has been found that: for where ${c}_{a}$ is the average spin-rotation constant and ${c}_{d}$ is the anisotropy in the spin-rotation matrix. Only the relative sign of these two constants was determined. Several earlier approximate methods of treating spherical rotor problems which involve the tensor part of the spin-rotation interaction are examined in the light of the present results.
Low-temperature spectra of chloroplast fragments

Abstract Absorption and fluorescence-excitation spectra of chloroplast fragments, obtained by sonic oscillation and differential centrifugation, were measured at −196°. Several chlorophyll pigments, including C-705, were resolved in the low-temperature spectra. No fractionation of the chlorophyll pigments was achieved by differential centrifugation. The smallest chloroplast fragments (those in the supernatant of a 173 000 × g centrifugation) contained the chlorophyll pigments in the same ratio as the intact chloroplasts. The fluorescence-excitation spectra showed that energy transfer between the pigments associated with the smallest fragments occurred to the same degree as in the intact chloroplasts. These results support the concept of a structural photosynthetic unit in which a C-705 molecule serves as an energy sink.
Effects of carbon nanotubes on electro-optical properties of dye-doped nematic liquid crystal

Electro-optical effects of planar nematic liquid crystal cells doped with dye and carbon nanotubes (CNTs) were investigated by utilizing the absorption property of the dye. Voltage-dependent transmittance and hysteresis measurements under applied ac and dc fields were presented. Cells doped with both Methyl Red and CNTs showed increased conductivity and capacitance, slower ac-rise switching time and dc-backflow on turn-off. The cells exhibited little hysteresis but those containing CNTs reduced residual dc by about 50%. First-order probe diffraction of permanent gratings revealed a correlation of ac-field-enhanced diffraction efficiency and Freedericksz threshold voltage.
A note on Green element method discretization for Poisson’s equation in polar coordinates

Abstract In the work described herein, the Green element method (GEM) is applied to arrive at new sets of element matrices for the solution of Poisson’s equation in polar coordinates. A unique flexibility possessed by GEM allows integration within a typical element. This special GEM characteristic, in addition to providing exact values of element coefficient matrices, facilitates the handling of nodal singularities and variable coefficients that accompany such problems. Numerical solutions provided by GEM confirm reliability.
The Warning against Idolatry: An Intertextual Examination of Septuagintal Warnings in Hebrews:

The Letter to ‘the Hebrews’ is concerned with the ultimate allegiance of its Christian audience. Scholarship on Hebrews, however, is not unanimous regarding the nature of the pressures and temptati...
Use of Molecular Epidemiology in Veterinary Practice

Molecular epidemiology is a relatively new branch of epidemiology that uses molecular biology methods to study health and disease in populations. This article gives an introduction to molecular epidemiologic terminology and methodology and its usefulness in large animal medicine and veterinary public health. Applications in source tracing and vaccine studies and insights into transmission dynamics, host specificity, and niche adaptation of infectious organisms are presented. Examples are drawn from a variety of diseases, organisms, and host species and range from the global level to the individual-animal level.
Effects of DDT on biochemical functions of fat body and muscle mitochondria isolated from the cockroach Blaberus discoidalis

Abstract Respiratory activity, ADP:O ratios and respiratory control by ADP were examined for fat body and muscle mitochondria isolated from the cockroach Blaberus discoidalis Serville following administration of a lethal dose of DDT. Both types of mitochondria were unaffected by the poisoning. Using 14 C-DDT it was found that 76% of the injected label accumulated in the fat body within 1 hr with 2% associated with the mitochondrial fraction. In vitro administration of DDT to fat body mitochondria decreased both the respiratory control by ADP and the ADP:O ratio. These findings indicate mitochondria are not affected by the levels of DDT reaching the tissues after poisoning. Therefore, the respiratory stimulus of DDT-poisoned insects is not the result of uncoupling oxidation and phosphorylation.
Effect of iron on acute pyelonephritis and later chronic changes

Effect of iron on acute pyelonephritis and later chronic changes. Administration of iron to rats exacerbated early inflammatory changes of pyelonephritis produced by intravenous inoculation of Escherichia coli . This effect was noted with four of eight strains of E. coli tested and was dependent on bacterial inoculum. Despite this increase in severity of acute pyelonephritis as judged by numbers of bacteria in the kidney and careful gross and microscopic evaluation, there was no enhancement of chronic changes seen 6 months later. Effet du fer sur la pyelonephrite aigue et les modifications tardives chroniques. L'administration de fer a des rats a exacerbe les modifications inflammatoires precoces de pyelonephrite produites par inoculation intraveineuse d' Escherichi coli . Cet effet a ete observe pour quatre des huit souches de E. coli utilisees et etait dependant de l'inoculation bacterienne. Malgre cette augmentation de severite de la pyelonephrite aigue jugee par le nombre de bacteries presentes dans le rein et une etude macroscopique et microscopique soigneuse, il n'y avait pas d'augmentation des modifications chroniques vues 6 mois plus tard.
Pulmonary Vascular Pressures Increase after Lung Volume Reduction Surgery in Rabbits with More Severe Emphysema

Abstract Background. Emphysema is a chronic disease of the lungs with destruction of terminal alveoli and airway obstruction. Lung volume reduction surgery (LVRS) is being investigated for the treatment of emphysema. Increasing resection volumes with LVRS may lead to worsening of carbon monoxide diffusing capacity (Dlco) despite improvement in compliance and flow. We hypothesized that the pulmonary circulation-related parameters, pulmonary artery pressure (PAP) and diffusing capacity (Dlco), may be used as indicators of the maximally tolerated LVRS resection volume. Methods. Emphysema was induced in 55 rabbits by endotracheal nebulization, with either single 15,000-unit (mild emphysema) or three 11,000-unit (moderate emphysema) doses of elastase. At Week 6, bilateral LVRS was performed via median sternotomy with an endoscopic stapler. Single-breath Dlco, static compliance, and PAP were measured prior to emphysema induction, preoperatively, and 1 week following LVRS. Animals were divided into the following groups: Group I (mild emphysema, 3 g resected), group III (moderate emphysema, 3 g resected). Results. All animals having LVRS had immediate postoperative increase in pulmonary vascular resistance (PVR) following lung resection. Mean PAP, however, remained elevated when measured 1 week after LVRS (sacrifice) in animals with moderate emphysema. This is in contrast to animals with mild emphysema, in which follow-up PAPs approached preoperative baseline. Conclusion. These finding suggests that sustained increased PVR, denoted by elevated PAP, is more likely to occur after LVRS in animals with more severe emphysema and larger volume resection. The spirometric and compliance benefits of greater resection volumes have to be weighed against the compromise in pulmonary vasculature in the effort to determine the ideal resection volume for various degrees of emphysema.
Two-year report of sealant effect on bacteria in dental caries

Teeth in which caries had penetrated the pits and fissures were sealed with an ultraviolet-light-polymerized sealant. Samples of carious dentin were taken from teeth that were not sealed and from teeth that were sealed, up to two years after the sealant had been placed. The major reduction in viable microorganisms occurred during the first two weeks, and there was a gradual reduction in the total count thereafter. At the end of two years, there was a 2,000-fold decrease in the number of cultivable microorganisms. Preliminary clinical and radiographic findings suggest that there was no progression of the carious lesions, but further studies are needed before this technique can be considered an alternative to conventional procedures.
Ground Water Yields and Inventory for Land-Use Planning in Crystalline Rock Areas of Wake County, North Carolina

Summary In urbanizing areas underlain by crystalline rocks an inventory of the usable ground water should form an important element in the land-use planning process. Land-use decisions are most often made upon water-well yield data alone, but these data do not address the inventory question. A method utilizing local geology, stream lowflow characteristics, and pumping test data permitted outlining portions of Wake County, North Carolina, which are more favorable and those which are less favorable for ground water supply development. Information from state-required 24-hour pumping tests on 232 wells was supplemented by information from an additional 100 wells whose initial yields were determined by shorter pumping tests. Comparison of the ground water inventory values on a per acre or per square mile basis with average water use at various residential densities provides information useful to the responsible political body as it decides about population density distribution and the need for surface water supplies. For Wake Country an average density of one residential unit per acre appears generally permissible before overdraft of the ground water supplies becomes a significant risk. By utilizing the ground water inventory and patterns of ground water yields from various rock types, county officials can maximize the effectiveness of public facilities funds. The technique appears useful for other parts of the Piedmont region of the southeastern United States.
Bioaccumulation of As, Cd, Cr, Hg(II), and MeHg in killifish (Fundulus heteroclitus) from amphipod and worm prey.

Abstract Elevated metal levels in fish are a concern for the fish themselves, their predators, and possibly humans who consume contaminated seafood. Metal bioaccumulation models often rely on assimilation efficiencies (AEs) of ingested metals and loss rate constants after dietary exposure ( k ef s). These models can be used to better understand processes regulating metal accumulation and can be used to make site-specific predictions of metal concentrations in animal tissues. Fish often consume a varied diet, and prey choice can influence these two parameters. We investigated the trophic transfer of As, Cd, Cr, Hg(II), and methylmercury (MeHg) from a benthic amphipod ( Leptocheirus plumulosus ) and an oligochaete ( Lumbriculus variegatus ) to killifish ( Fundulus heteroclitus ) using gamma-emitting radioisotopes. Except for MeHg, AEs varied between prey type. AEs were highest for MeHg (92%) and lowest for Cd (2.9–4.5%) and Cr (0.2–4%). Hg(II) showed the largest AE difference between prey type (14% amphipods, 24% worms). For Cd and Hg(II) k ef s were higher after consuming amphipods than consuming worms. Tissue distribution data shows that Cd and Hg(II) were mainly associated with the intestine, whereas As and MeHg were transported throughout the body. Calculated trophic transfer factors (TTFs) suggest that MeHg is likely to biomagnify at this trophic step at all ingestion rates, whereas As, Cd, Cr, and Hg(II) will not. Data collected in this study and others indicate that using one prey item to calculate AE and k ef could lead to an over- or underestimation of these parameters.
In Vitro reconstitution of calf brain microtubules: Effects of macromolecules

A comparative study has been carried out of the ability to reconstitute into microtubules of tubulins prepared by the Weisenberg and the cycle procedures. It was found that further purification of cycle tubulin by phosphocellulose chromatography made its ability to polymerize identical with that of Weisenberg tubulin. By adding to either tubulin the isolated proteins which copurify with tubulin in the cycle prodecure, it is possible to reduce their critical concentrations of microtubule formation to a value identical with that of cycle tubulin. It was demonstrated quantitatively that the effect of these nontubulin proteins could be mimicked by a variety of polycationic molecules, the most effective one being poly(L-lysine). A possible mechanism is described by which growing microtubules could be stabilized by subsequent addition of the nontubulin proteins. The conclusion is drawn that, at present, it is not known whether the proteins which copurify with tubulin are specific components of the microtubule system, or simply artefactually coprecipitated impurities.
How is asexuality different from hypoactive sexual desire disorder

Since around 2000, asexuality – conceptualised as a sexual orientation – has begun to emerge as an identity and a movement. Hypoactive sexual desire disorder (HSDD), which emerged in the late 1970s with the rise of sex therapy and is currently listed in the DSM, has gained increasing attention – promotion and a backlash of criticism – with the increased influence of the pharmaceutical industry in sex research. The relationship of these categories has often been noted but largely unexplored, and when explored, authors have tended to focus only on how much they do or do not overlap. This article examines the relationships and differences between asexuality and HSDD by examining the histories of each, the conceptual sources that each has primarily drawn on (various clinical/medical traditions vs. LGBT discourses and reactions against dominant beliefs about sexuality that asexuals find incongruent with their experiences); it examines how each functions in the primary contexts where they are used (asexual spac...
Assaulting the border: kabbalistic traces in the margins of Derrida

Cet article explore la pensee de Jacques Derrida en rapport avec la sagesse esoterique de la kabbale traditionnelle, un rapport explicitement revendique par Derrida. Ce rapport se decrit plutot comme une convergence que comme une influence : la convergence se fait sur le caractere textuel de l'etre et sur le role joue par le nom ineffable, l'indicible qui rend le dicible possible. Elle se manifeste egalement dans l'analyse du secret et de la circoncision.
Purification of cyclic fatty acid esters: a GC‐MS study

Gas chromatographic analysis of cyclic monomeric concentrates and fractions from argentation chromatography on packed columns containing SE-30, OV-25 and Apiezon L stationary phases yielded incompletely separated peaks representing the various isomers present in the mixture. Somewhat better separation was achieved using a 6 ft×1/8 in. column packed with 15% EGS on Chromosorb W. This column, when coupled to a mass spectrometer, yielded information concerning the composition of each of the isomeric components. Comparable results were obtained using a 50 ft×0.02 in. S.C.O.T. column with DEGS stationary phase and a 150 ft×0.01 in. capillary column coated with Apiezon L. While argentation thin layer chromatography proved useful, an argentation column method using silicic acid coated with 10% AgNO3 proved more efficient for larger scale preparations. Elution of the column with 2% diethyl ether in petroleum ether yielded material essentially free of conjugated linolenate. A comparison of the behavior upon argentation thin layer chromatography of conjugated methyl linolenate, methyl linoleate and cyclic monomer esters indicated that these esters migrated to the same relative position as methyl oleate.
Reciprocal Regulation of the Early Promoter Region of Bacteriophage HP1 by the Cox and CI Proteins

We have identified a transcriptional switch at the early promoter region of bacteriophage HP1. This switch controls the transcription of the early lytic operon from the P(R1) and P(R2) promoters and the transcription of the lysogenic operon from the P(L) promoter. The start sites of the three promoters were mapped, and using a chloramphenicol acetyl transferase assay, we have investigated the levels of transcription from the promoters in the absence or in the presence of two phage-encoded transcription factors: HP1 Cox and HP1 Cl. The HP1 Cox protein repressed the production of P(L) transcripts 30-fold, while the HP1 Cl protein repressed lytic transcription at least 70-fold. Binding sites for HP1 Cox and Cl were identified in the early promoter region; mutations of these sites eliminated transcriptional repression. In addition, a mutant Cl protein was isolated which is temperature sensitive for repression. Taken together, these data demonstrate the reciprocal regulation of a transcriptional switch in which the actions of the two phage-encoded proteins at the phage early promoters determine the choice between lytic and lysogenic growth.
Structure of Toxoplasma gondii fructose-1,6-bisphosphate aldolase.

The apicomplexan parasite Toxoplasma gondii must invade host cells to continue its lifecycle. It invades different cell types using an actomyosin motor that is connected to extracellular adhesins via the bridging protein fructose-1,6-­bisphosphate aldolase. During invasion, aldolase serves in the role of a structural bridging protein, as opposed to its normal enzymatic role in the glycolysis pathway. Crystal structures of the homologous Plasmodium falciparum fructose-1,6-bisphosphate aldolase have been described previously. Here, T. gondii fructose-1,6-bisphosphate aldolase has been crystallized in space group P22121, with the biologically relevant tetramer in the asymmetric unit, and the structure has been determined via molecular replacement to a resolution of 2.0 A. An analysis of the quality of the model and of the differences between the four chains in the asymmetric unit and a comparison between the T. gondii and P. falciparum aldolase structures is presented.
University Outreach in the Twenty-First Century

ABSTRACT Educational outreach, especially from land-grant universities, will have a more prominent, visible role in the twenty-first century. There is a widespread belief among university leaders that the effect of universities must reach beyond the limits of the campus to positively influence the social, cultural and economic well-being of constituents. Enhanced outreach efforts will involve all academic units and provide appropriate faculty rewards for their accomplishments. Existing extension/outreach organizations such as Cooperative Extension Services will expand their base to draw from the total university expertise and knowledge base. Funding will be a challenge as public resources become less available. Distance education through satellite communications and other advanced technology will be a growing part of education outreach.
Klebsiella pneumoniae necrotizing fasciitis and septic arthritis: an appearance in the Western hemisphere.

Background: Necrotizing fasciitis caused by Klebsiella pneumoniae is rare, with 11 documented cases in the literature, all occurring in Asia and the Middle East. These reports have become more freq...
Gravimetrically computed deflections of the vertical in Ohio

Deflections of the vertical were computed for five points over a range of 100 km in central Ohio, using free-air anomalies out to 1500 km and isostatic anomalies, with corrections, for the rest of the Earth. For ξ at all five points, and for η at three mints, agreement with the astronomically observed deflections was obtained to within 0.″67; errors in astronomic longitude are shown to cause disagreement in η at two points. The probable error of the gravimetrically computed deflection on the assumption of random variation of the mean anomalies of five-degree squares was computed to be ±0.″38; on the assumption of random variation of the mean anomalies of 30° squares, to be ±1.″15.
On the Arrow and Wilson impossibility theorems

A social welfare function is Arrovian if it is transitive-valued and satisfies IIA. We examine the logical relation between the statements (A) If f is Arrovian with domain 𝒫 then it is dictatorial if it satisfies the Pareto criterion and (W) If f is Arrovian with domain 𝒫 then it is dictatorial or inversely dictatorial if it is non-null and satisfies non-imposition. We exhibit a class of domains on which W implies A and another on which A implies W. We also present examples of domains on which one of the statements is true and the other is false.
Experimental observation of interfacial slippage at the boundary of molecularly thin films with gold substrates

Physisorbed monolayers and multilayers adsorbed on the surface electrodes of a resonating quartz microbalance produce shifts in both the frequency and amplitude of the oscillator. The shift in frequency results from mass loading and the shift in amplitude results from film dissipation effects. We have measured these shifts for molecularly thin nitrogen and krypton films and observe levels of film dissipation which cannot be adequately accounted for within the context of the ``no-slip'' boundary condition of hydrodynamics. The data provide strong evidence that the excess dissipation arises from slippage at the film substrate interface since the film thicknesses studied are negligible compared to the viscous penetration depths of the respective materials.
Hyaline body myopathy.

Abstract Muscle biopsy from two unrelated patients, a male aged 40 and a female aged 3, with relatively non-progressive limb weakness since infancy, revealed numerous subsarcolemmal glassy, hyaline appearing bodies present in 20–30% of the fibres. Type 1 fibre predominance was present, and the hyaline bodies were exclusive to type 1 fibres. The hyaline bodies were negative with oxidative enzyme and periodic acid-Schiff stains. Electron microscopy showed the hyaline bodies to contain amorphous granular material of unknown composition. No membrane separated the hyaline bodies from the surrounding sarcoplasm. Hyaline body myopathy most likely represents a distinct congenital myopathy because of its childhoot-onset, non-progressive course, and distinct morphological features.
FeMo Cofactor of Nitrogenase: A Density Functional Study of States MN, MOX, MR, and MI

The MN S = 3/2 resting state of the FeMo cofactor of nitrogenase has been proposed to have metal-ion valencies of either Mo4+6Fe2+Fe3+ (derived from metal hyperfine interactions) or Mo4+4Fe2+3Fe3+ (from Mossbauer isomer shifts). Spin-polarized broken-symmetry (BS) density functional theory (DFT) calculations have been undertaken to determine which oxidation level best represents the MN state and to provide a framework for understanding its energetics and spectroscopy. For the Mo4+6Fe2+Fe3+ oxidation state, the spin coupling pattern for several spin state alignments compatible with S = 3/2 were generated and assessed by energy and geometric criteria. The most likely BS spin state is composed of a Mo3Fe cluster with spin Sa = 2 antiferromagnetically coupled to a 4Fe‘ cluster with spin Sb = 7/2. This state has a low DFT energy for the isolated FeMoco cluster and the lowest energy when the interaction with the protein and solvent environment is included. This spin state also displays calculated metal hyperfin...
Superconducting Niobium Cavity Measurements at SLAC

The program of measurements at SLAC on superconducting niobium cavities is described. Results for TE and TM mode X-band cavities are presented. An RF magnetic breakdown field of 960 gauss and Q values greater than 1011 were measured for an electron beam welded TE011 mode cavity at 10.5 GHz. The best result for a TM mode cavity was a Q of 1.4 × 109 and a breakdown field of 360 gauss, limited probably by the quality of the electron beam weld. Data on the effect of exposure to air and to nitrogen are presented.
Impacts of control and communication system vulnerabilities on power systems under contingencies

Modern power grids rely heavily on their control systems operating over communication networks to mitigate the effects of stresses in the grid. However, the cascading phenomenon and blackouts remain possible if the initial disturbances in the power grid are accompanied by other system vulnerabilities such as failures of the communication and control systems that transmit and implement critical control signals. Understanding the effects of such vulnerabilities are important in the design of future smart grids. In this paper the vulnerabilities in the control and communication system are coupled with the load shedding mechanism and their effects on power-grid cascading behavior are revealed by means of simulation. In particular, the cascading failure behavior of the grid is investigated considering the effects of failures in the control and communication systems, as well as the topological location of the failures.
A short and efficient synthesis of grisan

A three-step synthesis of grisan (spiro[benzofuran-2(3H)-1′-cyclohexane]), using methoxymethoxybenzene and 1-chloromethylcyclohexene as starting materials, is described.
The Importance of Adverbs and Connectives in Teaching Reading

Author's summary.— The indispensable connectives that make connected discourse possible are the most difficult words in the foreign vocabulary. They seldom show any cognate relationship to English equivalents, and are seldom thought of aside from the requirements of sentence structure. Something more than haphazard presentation of these words is recommended.
Dilatometric investigations of fatty acid methyl esters

The coefficients of expansion and melting dilations were measured for methyl palmitate, methyl stearate, methyl arachidate, methyl behenate, and methyl oleate. The dilatometric curve for the heating cycle of methyl palmitate and methyl stearate in the solid state was composed of a linear section to 49 degrees below the melting point, followed by a curvilinear section to the melting point. The heating and cooling cycle curves for methyl palmitate show the same volume change from −38°C. to 29°C., but the shape of the curves is different. The same relation holds for methyl stearate from −38°C. to 37.5°C. “After-contractions” were found in volume measurements within a few degrees of the melting point of both esters. Equilibrated points were found within 0.5 degrees of the final melting temperature of methyl stearate. A striking similarity exists between curves for variation of the dielectric constant with temperature for long chain linear molecules and the dilatometric data.
A Not So Modest Proposal

The American Spelling Reform Association was founded over one hundred years ago with the avowed intention of making English spelling more regular and consistent. Their attempts and subsequent attempts at spelling reform have failed. With today's advances in speech synthesis and voice recognition by computer a regularized alphabet would enhance machine reading and writing.
Creating the digital logic concept inventory

A concept inventory (CI) is a standardized assessment tool that evaluates how well a student's conceptual framework matches the accepted conceptual framework of a discipline. In this paper, we present our process in creating and evaluating the alpha version of a CI to assess student understanding of digital logic. We have checked the validity and reliability of the CI through an alpha administration, follow-up interviews with students, analysis of administration results, and expert feedback. So far the feedback on the digital logic concept inventory is positive and promising.
Vehicle Stops by Police for Driving While Black: Common Problems and Some Tentative Solutions

Abstract A common set of problems currently surround analysis of vehicle stops by police for what has come to be called “driving while Black.” These common problems range from an exclusive focus on contemporary police practices to possible differences in the driving behavior of African Americans and Whites. The present research used observer-reported data from “Midwest City” at the start of the 1970s to propose and illustrate tentative solutions to the common problems that currently surround analysis of race and vehicle stops by police. The article concludes with discussion of the tentative solutions and the implications that follow from them.
Exercise Ventilatory Limitation: The Role of Expiratory Flow Limitation

Ventilatory limitation to exercise remains an important unresolved clinical issue; as a result, many individuals misinterpret the effects of expiratory flow limitation as an all-or-nothing phenomenon. Expiratory flow limitation is not all-or-none; approaching maximal expiratory flow can have important effects not only on ventilatory capacity but also on breathing mechanics, ventilatory control, and possibly exertional dyspnea and exercise intolerance.
Print-and-Peel Fabrication of Microelectrodes

We describe a facile and expedient approach for the fabrication of arrays of microelectrodes on smooth substrates. A sequence of print-and-peel procedures allowed for the microfabrication of capacitance microsensors using office equipment and relatively simple wet chemistry. Microfluidic assemblies with reversibly adhered elastomer components allowed for the transfer of patterns of metallic silver, deposited via Tollens’ reaction, onto the substrate surfaces. Electroplating of the silver patterns produced an array of micrometer-thick copper electrodes. Capacitance sensors were assembled by placing nonlithographically fabricated flow chambers over the microelectrode arrays. Triangular-waveform current-voltage (I/V) measurements showed a linear correlation between the capacitance of the print-and-peel fabricated devices and the dielectric constant of the samples injected into their flow chambers.
Translational regulation of chloroplast genes. Proteins binding to the 5'-untranslated regions of chloroplast mRNAs in Chlamydomonas reinhardtii

We have examined the effects of illumination, carbon source, and levels of chloroplast protein synthesis on trans-acting proteins that bind to the leaders of five representative chloroplast mRNAs. The accumulation of these five chloroplast mRNAs and the proteins they encode were measured in cells grown under identical conditions. Extracts from all cell types examined contain a minimum set of six chloroplast 5′-untranslated region (UTR)-binding proteins (81, 62, 56, 47, 38, and 15 kDa). Fractionation results suggest that multiple forms of the 81-, 62-, and 47-kDa proteins may exist. A 36-kDa protein was found in all cells except those deficient in chloroplast protein synthesis. Binding of the 81-, 47-, and 38-kDa proteins to the rps12 leader is effectively competed by the atpB or rbcL 5′-UTRs, indicating that the same proteins bind to all three leaders. In contrast, these three proteins do not bind to the nuclear-encoded α-1 tubulin leader, which bound novel proteins of 110, 70, and 43 kDa. Cis-acting sequences within the 5′-UTRs of two chloroplast mRNAs (rps7 and atpB) have been identified which are protected from digestion by RNase T1 by extracts enriched for the 81-, 47-, and 38-kDa proteins.
Human–Environment Interactions and Environmental Justice: How Do Diverse Parents of Asthmatic Children Minimize Hazards?

While environmental justice researchers have established enduring linkages between environmental hazards and poor populations, little is known about the human–environment interactions of urbanites of varying socioenvironmental positions. To investigate how humans interact with differentially polluted urban environments, 53 interviews with parents of asthmatic children living in the central city and the suburbs were conducted. Parents used four techniques to minimize the impact of hazards on their asthmatic child: modify the child's activities; modify home environment; move to another home; and collective action. With its focus on interactions between people and their environments, this study reveals micro-scale hazards and lack of control over the ambient environment as additional dimensions of environmental injustice.
Fatty acid biosynthesis in liver and adipose tissue from dogs

Abstract 1. 1. Production of CO 2 , fatty acids and glycerol from glucose and acetate was measured in slices of liver and adipose tissue taken from mature dogs. 2. 2. Acetate was the predominant carbon source for de novo fatty acid synthesis in both tissues. 3. 3. Fatty acid synthesis occurred at greater rates in adipose tissue than in liver. 4. 4. Glucose provided carbon for glycerol synthesis production in adipose tissue. 5. 5. Results support the concept that adipose tissue, and not liver, is the principal anatomical site for fatty acid synthesis in dogs.
Illiquidity and risk of commercial timberland assets in the United States

Abstract Using the BDS independent test and the bootstrapping method, this paper examines the relationship between return and risk of various timberland investment vehicles and the holding period. Results from the BDS test reject the null hypothesis of independent and identically distributed (i.i.d.) returns and results from the simulation indicate that the average quarterly return remains almost constant and thus independent of the holding period but the average quarterly risk (standard deviation) varies among different timberland investment vehicles. For private-equity timberland assets, the average periodic risk increases with the holding period, whereas for public-equity timberland assets, it stays relatively constant. Overall, there is some evidence that private-equity timberland returns as measured by various NCREIF timberland indices tend not to be independent and identically distributed, a violation of the key assumption for the modern portfolio theory.
Z-estimation and stratified samples: application to survival models

TheinfinitedimensionalZ-estimationtheoremoffersasystematicapproach to joint estimation of both Euclidean and non-Euclidean parameters in probability models for data. It is easily adapted for stratified sampling designs. This is important in applications to censored survival data because the inverse probability weights that modify the standard estimating equations often depend on the entire follow-up his- tory. Since the weights are not predictable, they complicate the usual theory based on martingales. This paper considers joint estimation of regression coefficients and base- line hazard functions in the Cox proportional and Lin-Ying additive hazards models. Weighted likelihood equations are used for the former and weighted estimating equa- tions for the latter. Regression coefficients and baseline hazards may be combined to estimateindividualsurvivalprobabilities.Efficiencyisimprovedbycalibratingoresti- mating the weights using information available for all subjects. Although inefficient in comparison with likelihood inference for incomplete data, which is often diffi- cult to implement, the approach provides consistent estimates of desired population parameters even under model misspecification.
Aldrin epoxidation by plant root extracts

Abstract Aldrin epoxidase activity of the cell-free pea and bean root preparations was located in the particulate fraction. High speed centrifugation at 250 000 g for 2 hr resulted in a pellet with almost all the activity of the crude cell-free preparations. While the epoxidase was stimulated by NADPH generating system in these cell-free root preparations, that in high speed centrifugation pellets was not. Aldrin epoxidase activity of the dwarf bean root homogenates was increased by addition of p -aminobenzoic acid (10 −4 M). This increase in activity is above that already manifested by Polyclar AT. No activity was detected in the dormant or germinating Alaska peas or dwarf beans until the 5th and 6th day, respectively.
Fracture, longevity, and damage tolerance of graphite/epoxy filamentary composite material

Description de l'etat des connaissances actuelles sur la rupture, la duree de vie et la tolerance a l'endommagement de composites a fibres graphite/epoxy
Predictors for medical students entering a general surgery residency: National survey results.

Background. The number of general surgery (GS) residency applicants had been decreasing before 2003. This national survey of fourth-year medical students elucidates factors related to the basic surgery clerkship that are associated with the decision to enter a GS residency. Methods. A national sample of 2250 fourth-year medical students from all 4-year allopathic US medical schools was surveyed in spring 2002. Multivariate analyses were performed to identify mutable predictors for students entering GS. Results. Data from 1531 fourth-year medical students from 121 different medical schools (response rate = 68%) showed that 5.6% planned to enter GS. In multivariate analyses, the strongest predictor of entering GS was satisfaction with the quality of attending teaching (odds ratio 2.14, P <.01) in surgery clerkships. Several clerkship factors, such as frequency of call nights and total hours worked., were not as strongly associated with entering GS residency, Subsequent analyses showed that predictors of satisfaction with the quality of attending teaching included intraoperative activities (ie, suturing, cutting, and stapling), having attending-led rounds, and performing a history and physical with an attending. Significant negative predictors of satisfaction included observing or retracting only in surgery. Conclusions. In this national survey, factors are identified that are significantly associated with students entering a GS residency. Some of these mutable factors may increase the pool of GS residency applicants.
Promoting tobacco cessation via the workplace: opportunities for improvement

Introduction Little research exists on the prevalence of evidence-based tobacco cessation practices in workplaces, employer promotion of state-sponsored quitlines and predictors of these practices. Methods Cross-sectional analysis of the 2008 Healthy Worksite Survey, a telephone survey administered to Washington employers with 50 or more employees (n¼693). The objectives were to describe workplaces’ implementation of evidence-based tobacco cessation practices and identify key predictors of implementation in order to highlight opportunities for interventions. Results Among these employers, 38.6% promoted quitting tobacco, and 33.8% offered insurance coverage for cessation medications and counselling, 27.5% referred no-smoking violators to cessation services, and 5.7% included the state-sponsored quitline in health promotion messages. Larger workplaces and workplaces with a wellness staff, committee or coordinator had greater insurance coverage for tobacco cessation, communications promoting tobacco cessation, and promotion of the state-sponsored quitline (p<0.01). Workplaces with a wellness staff, committee or coordinator referred more violators of no-smoking policies to cessation services (p<0.01). Conclusions In Washington State workplaces do little to promote tobacco cessation by their employees. The lack of tobacco cessation promoting practices at small businesses, restaurants and bars, and businesses without wellness personnel indicates an opportunity for finding and reaching current smokers at businesses with limited resources. By adopting inexpensive prevention efforts, such as promoting the state-sponsored tobacco cessation quitline, employers can help employees quit smoking and, thereby, assist in improving employee health and lower medical costs.
Combined ranking and selection with control variates

Nelson and Staum derived R&S procedures that employ control-variate estimators (CVs) instead of sample means to obtain more statistical efficiency. However, control-variate estimators require more computational effort than sample means, and effective controls must be identified. We present a new CV screening procedure to avoid much of the computation cost. We also present a two-stage CV combined procedure which captures the ability to eliminate inferior systems in the first stage and the statistical efficiency of control variates for selection in the second stage. An empirical evaluation is provided.
THE BETA-BINOMIAL MODEL: VARIABILITY IN OVERDISPERSION ACROSS METHODS AND OVER TIME

The beta-binomial model accounts for variability between samples as well as variability between judges (overdispersion), making it possible to combine responses across judges and replications. Overdispersion (measured by gamma) was examined in this 3-part study. (1) Groups of judges ( n = 53‐ 59) performed two replications each of a paired comparison and paired preference. Results showed that extent of overdispersion could not be predicted from the method. (2) The stability of gamma across discrimination methods (2-alternative forced choice [2-AFC], 3-alternative forced choice [3AFC], triangle and duo-trio) was also examined ( n = 103). Results indicated that gamma was largely consistent across 2-AFC, 3-AFC and triangle tasks, but it was higher in the duo-trio task. (3) The stability of gamma over time was also investigated ( n = 25). Results demonstrate that overdispersion varied over time with no clear pattern. In all cases, use of the beta-binomial model allowed responses across judges and replications to be combined, increasing the power achieved for a given panel size.
Personal Narratives in Individuals with High-Functioning ASD: A Lens Into Social Skills

Narrative assessment is a valid means for evaluating social pragmatic skills in high-functioning individuals with autism spectrum disorder (ASD). Speech-language pathologists (SLPs) typically analy...
Extension of The Laser-Pumped Ruby Maser to Millimeter Wavelengths

A brief description is given on the operation of a microwave ruby maser in which the pump signal is the optical emission of a ruby laser. For operation in the millimeter spectrum the application of a magnetic field of inordinately high intensity can produce Zeeman splitting of the Cr/sup 3+/ levels at millimeter wave energy in the ground state in ruby. To obtain population inversion by optical pumping on the levels requires that the ratio of maser frequency to temperature be v/sub ij/ / T <14.4 Gc/sec /spl deg/K. As the maser temperature is increased the spin lattice relaxation time T/sub 1/ decreases in addition to possibly decreasing with increasing magnetic field. Since the power required from the laser is estimated as that required to produce saturation of the optical pump transition in a time less thanT/sub 1/, then decreasing T/sub 1/ also requires increased laser emission. A broadening of the laser emission has been observed at increased power so that the limit on useful laser power can be given in terms of the absorption line width of the maser optical pumping transition. Treating these various effects conservatively indicates that the laser-pumped ruby maser can be operated over the entire millimeter spectrum, however. The design of an apparatus with a hard superconductor electromagnet producing the field intensity required to accomplish this objective is given.
Interactions of Nonaqueous Solvents with Textile Fibers: Part IV: Effects of Solvents on the Mechanical Properties of Various Textile Yarns

Despite the increasing importance of solvent-based textile processing, there is little systematic information available about the effects of various organic solvents on textile fibers. A recent program at TRI is designed to study the interactions between various nonaqueous solvents and different textile yarns, including polyamides, polyesters, polypropylene, cellulose acetate, and rayon. The interactions between the solvents and the fibers are described principally in terms of their effect on yarn mechanical properties. Furthermore, the interactions are systematized by application of the solubility parameter concept, and it is shown that this concept may be used as a first approximation to predict interactions between solvents and textile fibers.