cssi/SciSciGPT-SciSciNet huggingface dataset:
Simplified models of protein folding exploiting the Lagrange radius of gyration of the hydrophobic component

Abstract Studies are performed using an early proposed, but relatively little investigated, model that efficiently emulates a hydrophobic funneling effect in protein folding. Its simple form, introduced as a further interaction term going as the square of the separation distance, is suitable for initial searches of conformational space by parallel computation and special processors which use polynomial representation of pair-wise interactions. Use of such a term implies calculation of the square of the Lagrange radius of gyration, but weighted by hydrophobicity rather than the masses of the constituent particles. The unusual choice is justified by the observation that experimental protein structures have forms consistent with this Lagrange formalism for hydrophobic residues, and so compact model structures have appropriate density. However, since the long-range and square-power form strains open structures and leads to rapid generation of compact structures, such that for most of the simulation chain the movements result in intra-chain clashes, a rapid rejection algorithm is employed that prunes out similar but high energy structures. The studies also explore the choice of the simplest possible models which might be used to explore folding. Hence pancreatic trypsin inhibitor is modeled as a ‘string-of-beads’, where the beads represent residues of differing hydrophobicity. This model has only limited success, and because there are no identifiable common centers of interaction between the ‘string-of-beads’ model and all-atom protein representations, it encounters the difficulties: (a) of comparing such highly simplified models with observed structures, and (b) of using such models as a starting point for conversion to all-atom models. The conclusion is that this solvent treatment is best applied to all-atom simulations from the outset. Nonetheless, low energy predictions obtained in this simple study can be considered as having promising features, and provide interesting insight into protein folding and the funneling contribution.
A priori error estimates for numerical methods for scalar conservation laws part II: flux-splitting monotone schemes on irregular Cartesian grids

This paper is the second of a series in which a general theory of a priori error estimates for scalar conservation laws is constructed. In this paper, we focus on how the lack of consistency introduced by the nonuniformity of the grids influences the convergence of flux-splitting monotone schemes to the entropy solution. We obtain the optimal rate of convergence of (Δx) 1/2 in L∞(L 1 ) for consistent schemes in arbitrary grids without the use of any regularity property of the approximate solution. We then extend this result to less consistent schemes, called p-consistent schemes, and prove that they converge to the entropy solution with the rate of (Δx) min{1/2,P} in L∞(L 1 ); again, no regularity property of the approximate solution is used. Finally, we propose a new explanation of the fact that even inconsistent schemes converge with the rate of (Δx) 1/2 in L∞(L 1 ). We show that this well-known supraconvergence phenomenon takes place because the consistency of the numerical flux and the fact that the scheme is written in conservation form allows the regularity properties of its approximate solution (total variation boundedness) to compensate for its lack of consistency; the nonlinear nature of the problem does not play any role in this mechanism. All the above results hold in the multidimensional case, provided the grids are Cartesian products of one-dimensional nonuniform grids.
Evidence for horizontal gene transfer between Chlamydophila pneumoniae and Chlamydia phage.

Chlamydia-infecting bacteriophages, members of the Microviridae family, specifically the Gokushovirinae subfamily, are small (4.5–5 kb) single-stranded circles with 8–10 open-reading frames similar to E. coli phage ϕX174. Using sequence information found in GenBank, we examined related genes in Chlamydophila pneumoniae and Chlamydia-infecting bacteriophages. The 5 completely sequenced C. pneumoniae strains contain a gene orthologous to a phage gene annotated as the putative replication initiation protein (PRIP, also called VP4), which is not found in any other members of the Chlamydiaceae family sequenced to date. The C. pneumoniae strain infecting koalas, LPCoLN, in addition contains another region orthologous to phage sequences derived from the minor capsid protein gene, VP3. Phylogenetically, the phage PRIP sequences are more diverse than the bacterial PRIP sequences; nevertheless, the bacterial sequences and the phage sequences each cluster together in their own clade. Finally, we found evidence for another Microviridae phage-related gene, the major capsid protein gene, VP1 in a number of other bacterial species and 2 eukaryotes, the woodland strawberry and a nematode. Thus, we find considerable evidence for DNA sequences related to genes found in bacteriophages of the Microviridae family not only in a variety of prokaryotic but also eukaryotic species.
Variation in dentist service rates in a homogeneous patient population.

Previous studies in medicine and dentistry document wide variations in service rates across small areas, large regions, and providers. The practice patterns of providers and underlying differences in patient need are thought to be important sources of this variation. To control for variation in patient needs, we calculated service rates of 200 general dentists in Washington state based on a homogeneous, well-educated, upper-middle-class population of patients. Wide variations were found in the rates for many dental services. Dentists' practice beliefs and characteristics of the practice were sources of variation in the rates. The evidence is insufficient to determine whether undertreatment or overtreatment occurred among dentists with the lowest and highest expenditures per patient, respectively. However, the perceived oral health status of adult patients was lower in practices with the lowest total expenditures per patient than in practices with the highest total expenditures per patient, suggesting that undertreatment of adult patients in the lowest-expenditure practices may have occurred.
Bohr-Sommerfeld Quantization of Spin Hamiltonians

The Bohr-Sommerfeld rule for a spin system is obtained, including the first quantum corrections. The rule applies to both integer and half-integer spin. It is tested for various models, in particular, the Lipkin-Meshkov-Glick model, and found to agree very well with exact results.
Progressive dementia: personal and relational impact on caregiving wives

The purpose of this exploratory study was to examine the perceptions of 115 female spouse caregivers of early to moderate stage dementia patients. Based on patients' cognitive status, cross-sectional comparisons of two groups of caregiving wives were conducted. No group differences were found in measures of caregiver burden, depression, or personal gain. However, wives of patients with greater cognitive impairment experienced lower levels of mastery and more relational deprivation when compared to wives of patients with higher mental status. Supportive approaches might be directed toward helping early dementia caregivers restructure their understanding of, and participation in, their marital relationships in anticipation of changes ahead. Interventions aimed at enhancing a caregiver's sense of personal mastery may help reduce the negative effects of dementia on caregivers' well-being.
Vitamin and Mineral Supplement use by Full-Time Employed Women With Pre-School Children

Abstract Concerns about general nutrient intake, particularly of more nutritionally vulnerable population groups such as women of child-bearing age have stimulated discussion about whether to advocate the use of modest doses of general multivitamin-mineral supplements to help meet Recommended Dietary Allowances. The purpose of this study was to determine the use of vitamin and mineral supplements in women who are employed full-time and have children under the age of six. Another component of the study was to determine whether the nutrient content of supplement users' diets differed from that of the non-users' diets. Subjects were 102 women recruited from area child care centers. Nutrition information was obtained using the Harvard Food Frequency Questionnaire. The women ranged in age from 22 to 47 years, with a mean age of 33 years. Fifty-eight percent reported using supplements on a regular basis with 88% consuming a multivitamin two or more times per week. Twenty-seven percent reported consuming a multivitamin 6–9 times per week and 4% consumed ten or more multivitamins per week. Paired sample t-tests were used to compare vitamin and mineral intake with and without supplementation. For the nutrients calcium, folate, iron, vitamin A, vitamin B 12 , vitamin C, vitamin D, and zinc paired sample correlations of the vitamin or mineral with and without supplementation were significant (p
Cylinder Focus Lens Design for X-Ray Experiments on the Nova Laser

The Nova and Novette lasers' focusing lenses, with added cylinder elements, produce line foci for irradiating x-ray laser targets. Design, implementation, and results are discussed. An analysis of the focusing properties of a symmetric lens and cylinder lens combination is presented. It is shown that spherical aberration affects the line width and the intensity distribution in the line focus. In addition, expressions are derived which show that the line foci lie on curved surfaces.
The Determination of Chloride in Milk

Summary The direct titration of chloride in milk by modifications of Mohr's method, with silver nitrate and with potassium chromate indicator, yields results which are so erroneously high and variable that this method, even with a correction factor, is not considered suitable for the accurate determination of chloride in milk. The direct titration method with dichlorofluorescein indicator yields somewhat lower results, but results which are still considered too high and erratic to be relied upon. Indistinct endpoints with either indicator, and the adsorption of silver by protein, are pointed out as important sources of error. An easy and quantitatively precise modification of the Volhard method is proposed for determining chloride in milk. One combined reagent, containing standardized silver nitrate, nitric acid, and ferric alum indicator, is added to the sample and the percentage of chloride is determined by titrating with standardized potassium sulfocyanate. Sources of error and methods of improvement in other methods, as well as conditions necessary for accurate Volhard titrations, are described.
An autocorrelation theory of visual form detection: A computer experiment and a computer model

A theoretical model is described for the effect of the organizational properties of dotted visual forms on visual form detection. The model assumes that a human observer functions more as an organization detector than as a feature detector. It is supported by a wide variety of experimental studies of human perception.
Functional effects of fetal striatal transplants

Abstract Much interest has been generated in recent years by the finding that fetal brain tissue transplants into adult brain can survive and grow in the host brain. Most work has been done transplanting relatively homogeneous populations of dopaminergic nigral neurons. However, it is now clear that the more complex fetal striatal tissue, which contains multiple neuronal types, will also survive and grow when transplanted into excitotoxin-lesioned adult striatum. We review herein studies demonstrating that the fetal striatal transplants are functional in that they can elicit changes in behavior in the transplant recipients. The striatal transplants reverse the locomotor hyperactivity characteristic of bilateral excitotoxin lesions. However, there is some controversy about the reversal of the abnormal apomorphine- and amphetamine-induced locomotor responses by fetal striatal transplants into excitotoxin-lesioned striatum and the presence or absence of dopamine receptors within the transplanted tissue. We review the evidence for and against the existence of neuroanatomical connections between the host brain and the transplanted fetal striatal tissue. We also point out the possibility of neurotrophic factors mediating the recovery of spontaneous locomotor activity in light of recent evidence that neurotrophic factors may mediate the functional recovery following transplants of adrenal medulla tissue into dopaminergic deafferented striatum.
Response of dynamically compacted tungsten to high fluence neutron irradiation at 423–600°C in FFTF

Abstract When pure tungsten produced by dynamic compaction at 95.3% theoretical density was irradiated in FFTF at temperatures of 423–600°C and neutron doses as high as 14.4 × 10 22 n cm −2 ( E > 0.1 MeV), it densified 2–3% and became very brittle. The brittle behavior resulted in failure at grain surfaces and appears not to be related to neutron-induced transmutation or segregation of transmutants. Based on density change measurements, it can be concluded that significant cavity formation did not occur at these high neutron exposures.
Optimal isolation conditions for rainbow trout (Salmo gairdneri) hepatic ribosomes.

Abstract 1. 1. Isolation conditions for rainbow trout (Salmo gairdneri) liver ribosomes were optimized. 2. 2. Optimal initial buffer (Buffer I) concentrations were 250 mM sucrose, 50 mM Tris (pH 7.6, 25°C), 75 mM KCl, and 5 mM MgSO4·7H2O. 3. 3. Optimal concentrations for post-105 supernatant buffer (Buffer III) were 25 mM Tris (pH 7.6, 25°C), 75 mM KCl, and 8 mM MgSO4·7H2O.
A new IGBT behavioral model

Abstract In this paper, we present a new behavioral model valid for insulated gate bipolar transistors (IGBTs). The d.c. part of the model is based on an empirical formula for the IGBT and needs three data points on the I – V curves to generate the entire d.c. characteristics. The dynamic part of the model is based on a Hammerstein-like current source. A template written in the MAST language is created in Saber simulator based on this new model. The theoretical predictions of the model are compared with the experimental data available for IGBTs fabricated by various manufacturers and found to be in excellent agreement. Furthermore, the new model is consistently faster than the existing physical models in simulating various circuit topologies.
Five "Easy" Questions

This NRC report suggests approaches to overcoming obstacles to effective risk assessment such as lengthy delays in evaluating complex problems, substantial uncertainties that arise from the lack of data, the backlog of chemicals that have not been evaluated, and the continuing development of new materials requiring study.
Effects of a 1% hydrocortisone conditioner on haematological and biochemical parameters, adrenal function testing and cutaneous reactivity to histamine in normal and pruritic dogs.

The purpose of this double-blinded study was to examine the effects of a 1% hydrocortisone, leave-on conditioner on haematological and biochemical parameters, adrenal function tests, and cutaneous reaction to serial dilutions of histamine phosphate in normal dogs and those with pruritic dermatitis. Groups 1 and 2 each consisted of eight normal dogs. Seven pruritic dogs comprised Group 3. All dogs were bathed twice weekly for 6 weeks. Groups 1 and 3 had 1% hydrocortisone conditioner applied after each bath. Group 2 had vehicle from the conditioner applied after each bath. The amount of 1% hydrocortisone applied to the treated dogs ranged from 278 to 416 mg/m2 . Haematological and biochemical analysis and adrenocorticotrophic hormone (ACTH) stimulation tests were performed on all dogs on days 0, 14, 28, and 42. Mean values for all blood and serum parameters remained within normal limits during the study. Post-ACTH cortisol levels were significantly lower in Group 3 compared to Groups 1 and 2 on day 42 (P < 0.05) and when averaged over all days of the study (P < 0.05 and P < 0.01, respectively). Serum alkaline phosphatase levels were significantly lower in Group 3 on day 0, compared to days 14 (P < 0.05), 28 (P < 0.01), and 42 (P = 0.05). All dogs received intradermal injections of buffered saline and five serial dilutions of histamine phosphate on days 0, 14, 28, and 42. No significant differences were apparent among the groups in subjective and objective evaluation of intradermally injected dilutions of histamine. In this study, the use of a 1% hydrocortisone leave-on conditioner did not result in clinically evident adverse effects, and only minor changes in blood parameters were detected. Although mean values in all groups remained within reference ranges throughout the study, the finding of statistically significant lower post-ACTH cortisol concentrations in the pruritic dogs (Group 3) suggests that absorption of hydrocortisone may have occurred. The results of this study also show that this product does not significantly suppress cutaneous reactivity to histamine in normal and pruritic dogs.
The LAJ Cycle: A New Combined-Cycle Fossil Fuel Power System

Oak Ridge National Laboratory (ORNL) has developed a novel system for combined-cycle power generation, called the LAJ cycle. This system could serve as a basis for the development of a new generation of high-efficiency combined cycles. In one of several possible configurations of the new combined-cycle fossil fuel power system, natural gas enters the system at 4.0 MPa and about 300 K, is heated and reformed, and is transferred to a turbine at 4.0 MPa and 1200 K. The gas expands in the turbine to 0.6 MPa and 800 K, and then flows successively to heat exchangers and a condenser-separator, after which it is separated into two gas streams, one containing principally CO with some CH4 and water vapor and the other containing pure H2 . The CO and H2 flow to separate fuel cells and undergo electrochemical oxidation with the concomitant production of electricity. Separate streams of water and carbon dioxide (CO2 ) are produced, making this cycle compatible with carbon mitigation strategies based on sequestration. Model calculations indicate combined-cycle efficiencies greater than 70% based on the lower heating value of natural gas. The high efficiencies realized result from a combination of the high-pressure natural gas reformate expansion and the highly efficient CO and H2 fuel cells. Most of the power derives from the fuel cells in the system.Copyright © 2002 by ASME
Changes in the refractive index ellipsoid isotropies, symmetric anisotropies, and depolarization ratios of potassium hyaluronate solutions as a function of pH

A new method is presented for studying the tertiary and possibly the secondary structure of a biopolymer, which is applied to the pH-dependent structural transition of potassium hyaluronate solutions. The method involves a new application of Dirac dispersion theory polarization dependence measures to isotropic and anisotropic components of the refractive index ellipsoid. Changes in the dipole moment may also be observed by this method. The pH-induced changes in viscosity and optical properties of hyaluronic acid previously reported appear to be dependent on changes in secondary and tertiary structure.
The Property/Privacy Conundrum over Human Tissue

This paper analyzes court rulings on tissue samples as property and critiques objections that have been raised to the recognition of DNA samples as personal property. The cases are: Moore v. Regents of the University of California (1988, 1990), Greenberg v. Miami Children’s Research Institute (2003), and Washington University v.Catalona (2007). The paper argues that it is possible for the law to support both individual privacy and property rights in DNA, recognizing nevertheless that some unresolved questions remain, including what exercising those rights means on a practical level. Finally, it offers suggestions for changes in law based on those considerations.
Sequencing of Genomic DNA by Combined Amplification and Cycle Sequencing Reaction

Background: Despite considerable advances, DNA sequencing has remained somewhat time-consuming and expensive, requiring three separate steps to generate sequencing products from a template: amplification of the target sequence; purification of the amplified product; and a sequencing reaction. Our aim was to develop a method to routinely combine PCR amplification and cycle sequencing into one single reaction, enabling direct sequencing of genomic DNA. Methods: Combined amplification and sequencing reactions were set up with Big Dye™ sequencing reagents (Applied Biosystems) supplemented with variable amounts of forward and reverse primers, deoxynucleotide triphosphates (dNTPs), and input DNA. Reactions were thermal-cycled for 35 or 45 cycles. Products were analyzed by capillary electrophoresis to detect sequencing products. Results: Reactions using two oligonucleotide primers at a ratio of 5:1 (500 nM primer 1 and 100 nM primer 2), 125 μM supplemental dNTPs, and 35–45 thermal cycles optimally supported combined amplification and cycle sequencing reactions. Our results suggest that these reactions are dominated by PCR during early cycles and convert to cycle sequencing in later cycles. We used this technique for a variety of sequencing applications, including the identification of germline mutations/polymorphisms in the Factor V and BRCA2 genes, sequencing of tumor DNA to identify somatic mutations in the DPC4/SMADH4 and FLT3 genes, and sequencing of 16S ribosomal DNA for bacterial speciation. Conclusions: PCR amplification and cycle sequencing can be combined into a single reaction using the conditions described. This technique allows direct sequencing of genomic DNA, decreasing the cost and labor involved in gene sequencing.
Resource exhaustion, economic growth, and income distribution: A comparison of an optimization and a competitive equilibrium model

Abstract In this article we provide a detailed formulation of an intertemporal competitive equilibrium model of resource exhaustion and economic growth in a decentralized economy consisting of finitely lived generations. A brief description is provided in an earlier article by Chao, Kim, and Manne (1982). The algorithm from that article is employed to solve for an intertemporal competitive equilibrium. A comparison is then made between the competitive equilibrium approach and the optimization approach.
Special curriculum for surgery residents who fail the ABSITE

Abstract Purpose The American Board of Surgery In-Training Examination (ABSITE) documents surgical residents’ acquisition of surgical knowledge. From 1995 to 1998, after merging two general surgical residencies, 10 residents had ABSITE scores below the 30th percentile. A special curriculum was designed to address these knowledge deficiencies. The purposes of this study were to determine: (1) whether the special curriculum was effective, as measured by the next ABSITE, (2) whether the evaluation score for the special curriculum predicts the next ABSITE performance, and (3) how the special curriculum can help manage the knowledge-deficient resident. Methods Each resident filled out a questionnaire and met with the program director. The special curriculum ran from May 1 until the following March. Each resident presented a basic science conference and took the Association of Program Directors in Surgery Basic Science Course. Each resident studied a surgery textbook and took 4 examinations. Each resident was placed on probation but promoted to the next year in July. Their continuation in the residency depended on their performance in this special curriculum, clinical evaluations, and the next ABSITE. Results The questionnaire responses were: stopped studying: 10, surprised with low score: 9, no review of questions: 8, personal problems: 6, and test anxiety: 5. Basic Science conferences were above average or excellent. Conference attendance was 40%–80%. Evaluation scores were 57 to 95. The mean ABSITE percentile scores were initial = 18 (±8) and final = 48 (±35). The mean improvement was 31 (±29). The mean ABSITE standard scores were initial = 438 (±72) and final = 542 (±107) with a mean improvement of 104 (±61). Six out of 10 residents scored over 30% from 34%–97%. Four residents scored from 4%–23%. Six of the 10 residents were retained whereas 4 residents resigned. Conclusions The special curriculum provides an effective method with a due process for dealing with residents who have a deficiency of knowledge. The curriculum evaluation scores predicted the ABSITE outcome in only 70% of the residents and failed to correlate in 30%. This special curriculum separated the residents into two groups: one group passed the ABSITE with scores of 34% or above, and the other group failed, with ABSITE scores of 23% or below.
Magnetization switching of a metallic nanomagnet via current-induced surface spin-polarization of an underlying topological insulator

We consider a thermally stable, metallic nanoscale ferromagnet (FM) subject to spin-polarized current injection and exchange coupling from the spin-helically locked surface states of a topological insulator (TI) to evaluate possible non-volatile memory applications. We consider parallel transport in the TI and the metallic FM, and focus on the efficiency of magnetization switching as a function of transport between the TI and the FM. Transport is modeled as diffusive in the TI beneath the FM, consistent with the mobility in the TI at room temperature, and in the FM, which essentially serves as a constant potential region albeit spin-dependent except in the low conductivity, diffusive limit. Thus, it can be captured by drift-diffusion simulation, which allows for ready interpretation of the results. We calculate switching time and energy consumed per write operation using self-consistent transport, spin-transfer-torque (STT), and magnetization dynamics calculations. Calculated switching energies and times compare favorably to conventional spin-torque memory schemes for substantial interlayer conductivity. Nevertheless, we find that shunting of current from the TI to a metallic nanomagnet can substantially limit efficiency. Exacerbating the problem, STT from the TI effectively increases the TI resistivity. We show that for optimum performance, the sheet resistivity of the FM layer should be comparable to or larger than that of the TI surface layer. Thus, the effective conductivity of the FM layer becomes a critical design consideration for TI-based non-volatile memory.
Inductive methods and contract-signing protocols

Garay, Jakobsson and MacKenzie introduced the notion of abuse-free distributed contract-signing: at any stage of the protocol, no participant Ahas the ability to prove to an outside party, that A has the power to choose between completing the contract and aborting it. We study a version of this property, which is naturally formulated in terms of game strategies, and which we formally state and prove for a two-party, optimistic contract-signing protocol. We extend to this setting the formal inductive proof methods previously used in the formal analysis of simpler, trace-based properties of authentication protocols.
A split band-Cholesky equation solving strategy for finite element analysis of transient field problems

The paper describes the split-Cholesky strategy for banded matrices arising from the large systems of equations in certain fluid mechanics problems. The basic idea is that for a banded matrix the computation can be carried out in pieces, with only a small portion of the matrix residing in core. Mesh considerations are discussed by demonstrating the manner in which the assembly of finite element equations proceeds for linear trial functions on a triangular mesh. The FORTRAN code which implements the out-of-core decomposition strategy for banded symmetric positive definite matrices (mass matrices) of a coupled initial value problem is given.
Community-Centered Globalization: Modernization under Control in Rural Costa Rica

The retreat of the state from the development process throughout Latin America has placed added responsibility on local communities to improve local living conditions. Research on the impacts of globalization and tourism has tended to highlight the negative repercussions of such engagements, often portraying the hosts as helpless victims of savage capitalism and overbearing tourists. Examination of the introduction of small-scale development initiatives into a small rural community in Costa Rica reveals that the local community is anything but a passive recipient and may actively manage the very modest inclusion of tourism into its overall development strategy. Drawing on the theoretical contributions of Max-Neef, Escobar, and others, this research provides further evidence that integrated small-scale rural development initiatives can achieve modest success by capitalizing on existing resources, gradually broadening the economic mix and collaborating with similarly situated communities.
What really works: HR's role in building the 4 + 2 organization and an introduction to the case studies in the HR leadership forum

Leading in HR means building organizations that consistently and predictably outperform their competitors. In order to understand how HR can best contribute to enhancing firm performance, more than 60,000 pages of information from 200 firms in multiple industries over ten years were analyzed. These firms varied in size, and we complemented these broad extensive analyses with focused, in-depth exploration of issues of special interest. Only four foundation practices (focused strategy, execution, performance culture, and fast and flat organization) and four secondary practices (securing talent, committed leadership, industry-transforming innovation, and growth through mergers and partnerships) were found to be necessary to produce extraordinary returns to shareholders. Specifically, success required performing well in all four foundation areas, plus at least two of the secondary areas—we call this the 4 + 2 formula for sustained business success. © 2005 Wiley Periodicals, Inc.
Solute effects on ice recrystallization: An assessment technique

Reliable assessment of the effect of a solute upon ice recrystallization is accomplished with "splat cooling," the impaction of a small solution droplet onto a very cold metal plate. The ice disc has extremely small crystals, and recrystallization can be followed without confusing effects caused by grain nucleation. This method confirms the exceptionally strong recrystallization inhibition effect of antifreeze protein from Antarctic fish and shows that grain growth rate is a sensitive function of both grain size and solute concentration.
Exposure of emergency medicine personnel to ionizing radiation during cervical spine radiography

We studied the potential hazard of ionizing radiation exposure to health care workers who routinely stabilize the necks of trauma patients during cervical spine radiography. A clinical trauma model was developed using an Alderson RANDO Phantom ® artificial torso to simulate an actual patient. A radiation monitor was placed where a health care worker's fingers, hands, arms, and thyroid gland would be, and standard cervical spine radiographs were taken. The exposures to the finger positions then were repeated with the monitor inside a 0.5 mm lead-equivalent glove. The mean exposure to the finger for a single cross-table lateral radiograph was 174.5 mrem. The use of leaded gloves reduced this exposure to 0.3 mrem (a 99.9% reduction). For a single series of lateral, anteroposterior, odontoid, and swimmer's views, the total mean measured unprotected exposure to the finger of the hand positioned nearest the radiographic tube was 581 mrem and the exposure to the finger of the opposite hand was 230 mrem. If these simulated exposures are indicative of actual patient situations, a health care worker who holds the head of a trauma patient four times each week with unshielded hands would receive more than twice the maximum allowable annual occupational radiation exposure to the extremities recommended by the National Council of Radiation Protection and Measurements. We conclude that health care workers who routinely stabilize the necks of trauma patients during cervical spine radiography may incur a radiation exposure risk and that 0.5-mm lead-equivalent gloves provide an effective barrier to ionizing radiation.
Convergence of Diffusion with Concentrating Capacity

Abstract The diffusion of electric charge on a thin-film dielectric is described by an initial-boundary-value problem for a parabolic partial differential equation on a planar region. Consider the situation where conductivity on a given subregion increases to large values and the corresponding limiting problem has the total capacitance of that subregion all concentrated on the boundary of the complementary region. As the conductivity increases, the convergence of the solutions to that of the limiting problem is established, and convergence rates are obtained. The additional effect of deleting this concentrated capacitance is also estimated.
Lumbar Disk Herniation and Degenerative Disk Disease in Athletes

This work reviews the epidemiology, evaluation, treatment, and return-to-play guidelines for athletes with degenerative disk disease and herniated nucleus pulposus. Although most athletes with degenerative disk disease and herniated nucleus pulposus improve with conservative treatment, athletes with persistent symptoms may benefit from lumbar discectomy surgery. Lumbar interbody spinal fusion or disk-replacement surgery should only be considered after all other treatment options have been exhausted. Although some general consensus exists, return-to-play guidelines for the athlete with lumbar degenerative disk disease or disk herniation are not well-defined and require further investigation.
Mumps neuroretinitis in an adolescent.

able homonymous defect during field analyzer threshold testing. With one of us as the subject, we attempted to create an upper quadrant defect. While the test was running, the subject recognized a successful strategy for creating a defect (Fig. 2). If the subject fails to respond to the light stimulus in the chosen quadrant at the beginning of the test (when light stimuli are directed in four points, one per quadrant), the
SU-E-T-182: Delivery Verification of Tomotherapy Treatments Using Exit Detector Sinograms: A Phantom Study.

Purpose: The objective of this study was to use a liquid water female body phantom to investigate the feasibility of using helical Tomotherapy's exit detector data sinograms (EDDS) for quality assurance of Tomotherapy treatments.Methods: Delivery Verification software (DV‐Tool), described by Kapatoes et al., uses EDDS and daily mega‐voltage‐CT images for delivery sinogramreconstruction and subsequent dose computations. These dose distributions should reflect variations in patient's anatomy and machine delivery. Phantom was used to verify the robustness of the DV‐Tool for machine consistency over 2months, and sensitivity to weight loss and setup errors. Weight loss simulations were done by removing layers of bolus from the phantom's pelvis. Setup errors were simulated by performing known table shifts before the treatment. Two treatment plans simulating a breast and gynecological treatment plans were used for these evaluations. Reconstructed doses and dose volume histograms (DVHs) were analyzed in comparison to the plan DVHs by scaling the reconstructed PTV mean dose (PTV‐MD) to match the plan. PTV‐MD differences before and after machine output adjustments were evaluated. Results: Machine consistency check of gynecological plan revealed that the deviations were greater (±5%) during the week prior to target replacement. After output adjustments, the deviations for breast and gynecological plans agreed within ±1.0% and ±2.5%, respectively. Weight loss on the gynecological plan showed a correlation (R2=0.998) between lost thickness and increasing PTV‐MD by approximately 5%/cm. Setup errors on the breast plan showed broadening shoulder of the PTV DVH for shifts greater than 5mm. Volume at 20Gy for the right lung increased by 6% for 10mm shifts in both x and z directions. Conclusions: The DV‐Tool is sensitive to simulated weight loss, setup errors, and machine output. Exit detector data and the DV‐Tool have great potential for monitoring patient's delivered treatments. However, clinical workflow needs to be established.
The Strategic Use of Gain- and Loss-Framed Messages to Promote Healthy Behavior: How Theory Can Inform Practice

Message framing provides a theoretically grounded approach to the development of effective health messages. In this study, we review the state of research and theory on message framing (Rothman & Salovey, 1997), and how it can inform efforts to enhance health practices throughout the cancer care continuum. Gain-framed appeals are more effective when targeting behaviors that prevent the onset of disease, whereas loss-framed appeals are more effective when targeting behaviors that detect the presence of a disease. In light of these findings, we consider how message frames may affect other types of health behaviors and identify the need to understand better the processes that shape how people construe health behaviors.
Application of Biological Learning Theories to Mobile Robot Avoidance and Approach Behaviors

We present a neural network that learns to control approach and avoidance behaviors in a mobile robot based on a form of animal learning known as operant conditioning. Learning, which requires no supervision, takes place as the robot moves around an environment cluttered with obstacles and light sources. The neural network requires no knowledge of the geometry of the robot or of the quality, number, or configuration of the robot's sensors. In this article we provide a detailed presentation of the model, and show our results with the Khepera and Pioneer 1 mobile robots.
Inmate Public Autoerotism Uncovered: Exploring the Dynamics of Masturbatory Behavior Within Correctional Facilities

In correctional settings, some offenders engage in a specific type of sex offense, namely public autoerotism, an aggressive form of masturbatory behavior designed to harass, antagonize, or unsettle employees. This article examines interview data with male inmates who admitted to intentionally exposing themselves to female correctional employees. Using a subcultural sociological framework, specifically Sykes and Matza's (1957) “techniques of neutralization,” we explain why some inmates persist in public autoerotism, despite the presence of institutional rules that prohibit this type of behavior. We discuss the implications of this research for the contemporary development and theoretical significance of neutralization theory. Also, suggestions are provided as to how correctional administrators can reduce or eliminate this form of deviant behavior.
WE-G-211-05: Advances in X-Ray Luminescence Computed Tomography: Towards In-Vivo Imaging of Radioluminescent Nanophosphors

Purpose: Radioluminescent nanophosphors (RLNPs) show great promise for imaging biological processes in vivo, at the molecular level, and for enhancing the delivery of cytotoxic therapy within the target volume of a radiation treatment. As progress is made towards these goals, there is a need for an imaging modality that can quantitatively measure the distribution of RLNPs in vivo, with high sensitivity and spatial resolution. X‐ray luminescencecomputed tomography (XLCT) is best placed to meet all these requirements. In this scheme, collimated beams of X‐ray radiation selectively excite RLNPs, producing optical light within a narrowly‐defined volume. Optical measurements of the photons diffusing out of the subject can be interpreted as projective measurements and reconstructed into tomographic images. Methods: As a proof of concept, we built a prototype XLCT system and acquired projective data for near‐IR‐emitting RLNPs embedded in various phantoms. A novel reconstruction scheme that includes a model of light propagation in biological tissue was developed and evaluated on XLCT scans with sparse angular sampling. Results: Imaging in an optically‐diffusive medium shows that imaging performance is not affected by optical scatter; furthermore, the linear response of the reconstructed images suggests that XLCT is capable of quantitative imaging.Reconstruction that combines models of light and X‐ray propagation in tissue was found more accurate for sparsely‐sampled datasets. Conclusion: Based on phantom experiments, we found XLCT to be a feasible approach for imaging RLNPs tomographically. As we advance towards our goal of imaging RLNPs in live animals, we are designing and building a new imaging set‐up with improved X‐ray collimation and light collection efficiency.
Smoke Measurements: An Assessment of Correlations Between Laboratory and Full-Scale Experiments

An extensive review is presented demonstrating the nature of comparison between full-scale fire smoke data and test method results for materials. These correlations are presented in terms of consistent parameters established through a development of the governing equations for smoke concentration and light attenuation. Visibility data limited to light transmission through smoke are also presented. The complex dependence of smoke production on many parameters acting in fire growth limits the success of simple correlation methods. Recommendations are made for further research to establish a sound basis for correlations, and the prediction of smoke obscuration due to fire.
Polarizability of the Neutron

Experiments on scattering of low-energy neutrons by heavy elements may give information concerning the electric polarizability of the neutron. The relation of the electric polarizability to the low-energy neutron scattering data is developed. One pertinent experiment is discussed and from this an upper bound on the polarizability is obtained. This upper bound to the polarizability $\ensuremath{\alpha}$ is an order of magnitude larger than the meson-theoretic estimate of $\ensuremath{\alpha}$. If the value of $\ensuremath{\alpha}$ is as small as is predicted by meson theory, or by an analysis of the pion photoproduction data, then it is unlikely to be observed in neutron scattering experiments of the presently achievable accuracy.
Dependence of target redundancy effects on noise conditions and number of targets

In a letter identification task using a four-position array, reaction time (RT) decreased as a negatively accelerated function of the number of targets, both with and without noise letters in nontarget positions. The effect was much greater in the noise condition, in which each redundant target replaced a noise letter. In such situations, the redundant-targets effect should probably be attributed to noise reduction rather than to redundancy. Scaling analysis of the RT distributions indicated that neither noise nor redundancy affects the rate of growth of excitatory strength, but that both affect the time at which growth begins. Excitatory strength grew as a function of the number of redundant targets according to a principle of decreasing gain, with much greater growth in the noise conditions. Further experiments indicated that whether noise is manipulated between or within subjects is important. Unless all stimuli present are reliabl targets, redundancy effects are eliminated or reduced in no-noise conditions.
Mutation analysis with coverage discounting

Mutation testing is an established technique for evaluating validation thoroughness, but its adoption has been limited by the manual effort required to analyze the results. This paper describes the use of coverage discounting for mutation analysis, where undetected mutants are explained in terms of functional coverpoints, simplifying their analysis and saving effort. Two benchmarks are shown to compare this improved flow against regular mutation analysis. We also propose a confidence metric and simulation ordering algorithm optimized for coverage discounting, potentially reducing overall simulation time.
Application of the grating objective speckle method to composite materials

The grating objective speckle method has been applied in whole-field strain analysis of carbon-fiber-woven polyimide-composite materials. A sequence of rosette fringe patterns was obtained from one single specklegram, indicating displacement components along four different directions with a 45-deg interval. The spatial frequencies, which represent the sensitivities of the fringe intervals, were 2400 l/mm forU x ,U y and 1697 l/mm forU45 andU135. Normal strain components, ɛ x , ɛ y , ɛ45, and ɛ135, were trasformed to quantitative topographic representations by coupling to a digital computer system. Shear strain can be determined by the rosette equations.
Localization and orientation of the γ-Tubulin Small Complex components using protein tags as labels for single particle EM

γ-Tubulin Small Complex (γ-TuSC) is the universally-conserved complex in eukaryotes that contains the microtubule (MT) nucleating protein: γ-tubulin. γ-TuSC is a heterotetramer with two copies of γ-tubulin and one copy each of Spc98p and Spc97p. Previously, the structure of γ-TuSC was determined by single particle Electron Microscopy (EM) at 25 A resolution. γ-TuSC is Y shaped with a single flexible arm that could be the key to regulating MT nucleation. EM gold labeling revealed the locations of γ-tubulin at the top of the Y. In vivo Fluorescence Resonance Energy Transfer (FRET) suggested the relative orientations of Spc98p and Spc97p but did not distinguish which large subunit formed the flexible arm. Here, using fluorescent proteins as covalently attached tags, we used class averages and 3D random conical tilt reconstructions to confirm the in vivo FRET results, clearly demonstrating that the Spc98p/97p C-termini interact directly with γ-tubulin. Most significantly we have determined that the flexible arm belongs to Spc98p and our data also suggests that the N-termini of Spc98p and Spc97p are crossed. More generally, our results confirm that despite their small size, covalently attached fluorescent proteins perform well as subunit labels in single particle EM.
Compact Fourier transform infrared spectrometer inside a glove box: Fourier transform spectroelectrochemistry and other applications

Abstract Use of a compact Fourier transform infrared (FT-IR) spectrometer inside a glove box to investigate air and moisture sensitive compounds is reported. The FT-IR spectrometer, manufactured by Midac Co., measures 18 cm × 28 cm × 61 cm and can be conveniently placed inside a standard glove box (Vacuum Atmospheres). This match of a low cost, compact FT-IR spectrometer with widely available glove box technology affords researchers a simple, routine method for acquiring FT-IR data for air and moisture sensitive compounds. Several applications are illustrated, including reaction kinetics and FT-IR spectroelectrochemistry. A design for an FT-IR spectroelectrochemical cell is also described.
Photoemission study of the transition from the insulating to metallic state in ultrathin layers

The transition from the insulating to metallic state in ultrathin Pb films was studied using high-resolution photoemission. The states near E{sub F} were probed as Pb was deposited onto a thin insulating layer, thin enough to reduce macroscopic charging. The results, which experimentally show a vanishing of states at E{sub F}, are consistent with the arguments of Efros and Shklovskii based on electron-electron interactions, and as far as we know are the first {ital in situ} study of the electronic properties as one goes from the insulating to metallic state in a two-dimensional system. {copyright} {ital 1997} {ital The American Physical Society}