cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of 3-Ethylthiopropionate in Ethionine Metabolism and Toxicity in Rats

The potential role of the pathway for ethionine catabolism involving the intermediate formation of 3-ethylthiopropionate in the etiology of ethionine hepatotoxicity was studied in rats. Rats were fed diets containing graded levels of 3-ethyl-thiopropionate, an intermediate of this pathway, for three weeks. A dietary level as low as 0.4% was toxic to rats, resulting in depressed growth and food intake, decreased blood hemoglobin levels and darkened and enlarged spleens. All animals fed 3-ethylthiopropionate expired a volatile sulfur compound that was identified as ethanethiol by gas chromatography using both a general flame ionization detector and a sulfur specific flame photometric detector. Rats fed diets containing either 0.8% ethionine or 3-ethylthiopropionate exhibited an 80% decrease in body weight gain over a three-week period compared to controls. Spleens were markedly darkened and enlarged and spleen iron content was 6-fold and 1.5-fold higher than controls in 3-ethylthiopropionate-fed and ethionine-fed rats, respectively. Liver concentrations of reduced and total glutathione were 30% higher than controls in ethionine-fed rats. There results document the marked toxicity of 3-ethylthiopropionate and ethionine and suggest that this pathway for ethionine catabolism may be involved in some of the numerous reported metabolic aberrations as a result of acute or chronic ingestion of ethionine.
An integrated pharmacodynamic analysis of erythropoietin, reticulocyte, and hemoglobin responses in acute anemia

Purpose. To determine by pharmacodynamic (PD) analysis physiologically relevant parameters of the cellular kinetics of erythropoiesis in acute anemia.
An Analysis of 'Fixed-Up-To' (FUT) Pricing Using a Stochastic Model of Consumer Behavior

"Fixed-Up-To" (FUT) tariffs, which are commonly used for pricing telecommunication services, are made up of three parts: a monthly subscription fee (or fixed fee), a usage-limit (or allowance), and an over-limit rate that is used for pricing consumptions in excess of the usage-limit. Typically, the consumption of a service is metered and billed separately for each billing cycle. Consequently, a consumer decides on using the service at an instant based on the inventory of allowance still available to him at that moment, the time left in his ongoing billing cycle, and the over-limit rate. Drawing from the finite-horizon inventory theory, we propose a stochastic model to capture this decision-making process. We provide a closed-form expression for the utility that the consumer gets from an FUT pricing plan. We then examine a monopolist's second-degree price discrimination problem in which consumers are offered a menu of FUT plans to choose from. We model two types of consumer heterogeneity: that in the rate at which opportunities to use the service arrive, and that in the average willingness-to-pay per opportunity. We characterize the optimal FUT price menu and also numerically compare FUT pricing with two-part tariffs and other alternatives. We prove that, in contrast with well-known findings in the literature on nonlinear pricing, there exist situations in the case of FUT pricing in which it is always optimal to serve both "high" and "low" type consumers regardless of their relative proportions. We also make a methodological contribution -- which is combining the finite-horizon inventory theory with the economic theory on second-degree price discrimination.
Fostering Justice Throughout the Curriculum

While clinics and pro bono programs are the primary ways in which law schools foster justice and public service, they should not carry this burden alone. Issues of public service, law reform and access to justice should be fully incorporated into the law school experience so that each student understands and becomes committed to becoming a "public citizen having special responsibility for the quality of justice." This article presents a number of approaches to foster justice and public service throughout the curriculum. The required course in the Legal Profession or Professional Responsibility must cover lawyers’ obligations to perform pro bono service, to act to reform the law and to ensure equal access to justice. Other substantive courses might expand their coverage so students learn the law needed for public service and understand the need for law reform. Skills courses and competitions should include problems affecting the neediest. Both types of classes should begin to support experiential components in which students serve, learn and reflect upon these experiences. The scholarly mission of the law school also should include these values through presenting issues of access to justice and public service in scholarly colloquia and including community based research in conjunction with classes, in seminars, in think tanks, and as special projects. Although clinical programs have provided the major window to these issues, we should act to maximize the potential of the clinical program by including institutional critique and law reform. Finally, pro bono programs, too, can be improved by including reflection and greater faculty involvement. Taking these steps will address our ethical responsibilities as law teachers and may ameliorate the negative effects law school has been found to have on students’ motivation to pursue public interest careers and pro bono work.
Plasma Measurements Near the Earth’s Bow Shock: Vela 4

The supersonic flow of solar wind plasma past the earth’s magnetic field is now known to produce a well defined, essentially permanent standing shock wave (Ness et al., 1964; Gosling et al., 1967; Burlaga and Ogilvie, 1968). Because collisional mean free paths in the solar wind are much larger than the shock’s dimensions and therefore cannot play a direct role in the shock’s formation, collective (wave particle) interactions must provide the necessary dissipation. Measurements of the thickness of the magnetic transition (Heppner et al., 1967) indicate that the shock is too thin (much less than an ion cyclotron radius) to result from magnetic wave turbulence such as Alfven wave turbulence suggested by Kennel and Sagdeev (1967). Tidman(1967) indicated that a likely alternative would be electrostatic ion wave turbulence driven by interpenetrating ion beams, and measurements of high frequency electric and magnetic field fluctuations published by Fredricks et al. (1968) and Scarf et al. (1970) show that electrostatic turbulence is likely to be the dominant dissipation mechanism. However, a necessary requirement for the instability of electrostatic waves with respect to small currents or interpenetrating ion beams is T e≫T i, and recent observations (Montgomery et al., 1969; Montgomery et al., 1970) show that the bow shock remains well defined for T e/T i as small as 0.6. This paper briefly presents measurements of electron and positive ion velocity distributions that provide evidence for electron preheating near the leading edge of the shock. The resulting increase in T e/T i may be large enough to cause significant destabilization of ion waves in the region where ion heating is observed to occur.
A comparison of the ladder and full-order magnetic models

Predictions of the reduced-order ladder model and the full-order extended cantilever model are compared with the measured behavior of an experimental multiple-output flyback converter. The flyback transformer geometry was chosen to closely follow the idealizing assumptions that lead to the ladder approximation, including use of a pot core with full-width copper foil windings. In spite of this, the ladder model fails to predict the observed waveforms and the mode of operation. The full-order extended cantilever model does indeed correctly predict the operating mode and the observed waveforms. Model parameters are measured using a network analyzer. Conditions on the validity of these measurements are derived using Middlebrook's extra element theorem.
Physiologic and pathologic profiles of circulating human prolactin.

Abstract These radioimmunoassay studies were designed to test three hypotheses: (1) prolactin plays a major role in regulation of mammary function; (2) in the normal woman, prolactin is not a major obligatory factor in gonadal and menstrual cycle regulation; and (3) assessment of alterations in circulating prolactin concentration in response to stimulatory agents is useful in the evaluation of the hypothalamic-pituitary axis. (1) During pregnancy, serum prolactin increased progressively to term. Suckling resulted in a prompt increase in prolactin concentrations. (2) Daily prolactin determinations during the menstrual cycle revealed no cyclic pattern and no significant daily variation. (3) Increase in prolactin response to TRF in nine patients with idiopathic galactorrhea, eight of whom had amenorrhea, was similar to that observed in normal control subjects. Administration of l -dopa resulted in a decrease in prolactin in normal women, women with idiopathic galactorrhea, women following hypophysectomy, a patient with primary hypothyroidism, and in a patient with a chromophobe adenoma. These data support the validity of the first two hypotheses and suggest that further studies on the response to administration of hypothalamic-releasing factors may be useful clinical tools to distinguish neoplastic from nonneoplastic states.
Maintaining strong cache consistency in the World-Wide Web

As the Web continues to explode in size, caching becomes increasingly important. With caching comes the problem of cache consistency. Conventional wisdom holds that strong cache consistency is too expensive for the Web, and weak consistency methods such as Time-To-Live (TTL) are most appropriate. The article compares three consistency approaches: adaptive TTL, polling-every-time, and invalidation, using prototype implementation and trace replay in a simulated environment. Our results show that invalidation generates less or a comparable amount of network traffic and server workload than adaptive TTL and has a slightly lower average client response time, while polling-every-time generates more network traffic and longer client response times. We show that, contrary to popular belief, strong cache consistency can be maintained for the Web with little or no extra cost than the current weak consistency approaches, and it should be maintained using an invalidation based protocol.
Model of nuclear excitation by electronic motion in intense laser fields

A simple model of coupled electronic and collective nuclear motion is used to study energy-transfer processes in the presence of intense short-wavelength laser fields. The complete Hamiltonian of the model includes distinct nuclear, electronic, and laser-field terms. A semiclassical method of extracting spectral information from the generated trajectories of the Hamiltonian is used to calculate laser-electronic-nuclear energy-transfer rates. The nuclear term describes a deformed heavy nucleus; it sufficiently treats the collective nuclear motion, which is lower in frequency than that which would be given by an individual-particle nucleon model. We specifically report on the dynamics of this model, and on the energy transfers that ensue, in the presence of an x-ray laser field, as a function of the electron radial distance. This general problem is of basic interest in the studies of laser-driven nuclear excitation.
Development of a Top-View Numeric Coding Teaching-Learning Trajectory within an Elementary Grades 3-D Visualization Design Research Project.

Abstract This article explicates the development of top-view numeric coding of 3-D cube structures within a design research project focused on 3-D visualization skills for elementary grades children. It describes children's conceptual development of 3-D cube structures using concrete models, conventional 2-D pictures and abstract top-view numeric representations integrated with the Geocadabra Construction Box, a computer interface that simulates these representations dynamically.
Explaining outcome type interactions with frame: Aspiration level and the value function

Research on framing effects has revealed cases where the type of outcome at risk (e.g., human lives vs. animal lives) affects the magnitude of the framing effect. Some authors have appealed to the shape of the value function as predicting when framing effects will occur: The more valuable the outcome type, the more nonlinear its value function, and the larger the resulting framing effect (Levin & Chapman, 1990). However, having a more or less nonlinear value function cannot explain situations in which participants strongly prefer the same option in both frames. Another factor that may be at work in these types of outcome effects is an aspiration level (AL; Lopes, 1987; Schneider, 1992), which determines how acceptable the options are and combines (or competes) with the risk attitude encouraged by frame. The results described here indicate that differences in the shape of the value function between outcome types are evident but are inconsistent between framed losses and gains, though nonlinearity in the value function can be increased with a manipulation that also encourages framing effects. The results also demonstrate that an AL can lead to the same predominant risk preference in the positive and negative frame. These findings indicate that the shape of the value function and the AL each play a role in outcome type interactions with frame, and in some cases, a combination of the two factors may be at work.
Design considerations for high packaging density optical bus array

In this paper, a crosstalk model is developed to study the packing density and interconnect distance limitations of an optical interconnect system employing polymer-based single-mode bus arrays. The upper limit of channel packing density (1250 channels/cm at interconnect distance of 5 cm) is determined for the first time using the crosstalk model, in which channel cross-coupling among an infinite number of waveguides is considered. Computer simulations are provided together with the proven experimental results. It is shown that there is a threshold of channel separation due to channel cross-coupling, which results in a tradeoff between channel packing density and interconnect distance. Waveguide dimension closer to the cutoff boundary of second mode (E12X) is preferred for an optimum design.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Jitter-aware time-frequency Resource Allocation and packing algorithm

One of the main components of the next generation protected military satellite communication systems is Dynamic Bandwidth Resource Allocation (DBRA). A centralized DBRA algorithm on the satellite dynamically grants terminals time and frequency resources as their traffic demands and channel conditions change, leading to significant increase in the overall system throughput.
Explicit Self-Regulated Strategy Development Versus Reciprocal Questioning: Effects on Expository Reading Comprehension Among Struggling Readers.

The effects of 2 rigorous strategic approaches to reading comprehension for 32 5th-grade students who struggle with reading were investigated. The first approach, TWA (Think before reading, think While reading, think After reading), was taught following explicit self-regulated strategy development instructional procedures (K. R. Harris & S. Graham, 1999). The second approach, reciprocal questioning (RQ), was taught following Cooperative ReQuest procedures developed by A. V. Manzo, U. C. Manzo, and T. H. Estes (2001). Compared with RQ students, TWA students improved significantly (with medium to large effect sizes) on 5 oral reading comprehension measures. There were no significant differences, however, between groups on 3 written comprehension measures, self-efficacy, or motivation. Students were positive about each intervention.
Calculation of phase equilibrium in Al-Li alloys

Abstract Stable and metastable phase equilibria in Al-Li alloys are investigated using a phenomenological free energy model. In this model, short range order in the solid phases is taken into account within the tetrahedron approximation of the Cluster Variation Method. For the liquid phase, a subregular solution model is used. The energy parameters entering the free energy description of each phase are determined by reproducing selected experimental thermodynamic data and equilibrium concentrations in the phase diagram. The entire equilibrium phase diagram is then computed. In addition, metastable equilibrium between the Al-rich f.c.c. solid solution and the Al3 Li phase is analyzed. A metastable miscibility gap is predicted to occur within the Al-rich solid solution below 400 K.
Have Mesons Composed of Charmed Diquarks Been Discovered

I suggest that the structure observed between $\sqrt{s}=3.9 \mathrm{and} 4.5$ GeV at SPEAR is due to the presence of exotic mesons composed of a charmed diquark and antidiquark. Arguments for the existence of such mesons are reviewed. The characteristic features, i.e., masses, narrow widths, and abundance, which enable them to explain the data are presented. Further properties and yet another narrow meson with $m\ensuremath{\approx}6.7$ GeV/${\mathit{c}}^{2}$ is predicted.
How to use calorimetry to distinguish a microcrystalline structure from an amorphous structure

Abstract Observation of the thermal manifestation of the glass transition is the traditional method for identifying a liquid-like structure. A microcrystalline structure can be identified from the thermal signal of its transformation, by grain growth, to a coarser polycrystalline assembly. The clearest calorimeter signal is the isothermal one, which is monotonically decreasing, unlike the peaked signal for transformations by nucleation and growth. The scanning signals of the two processes are also different in several, more subtle respects.
Analysis of ultraviolet radiation effects on yield stress of polymethyl methacrylate.

Yield stress of polymethyl methacrylate subjected to vacuum UV radiation is function of strain rate, tensile test temperature and irradiation dose
Alternative α-synuclein transcript usage as a convergent mechanism in Parkinson's disease pathology.

The protein α-synuclein is implicated in Parkinson's disease. Rhinn and colleagues perform gene expression analysis and find that specific α-synuclein transcripts are preferentially associated with Parkinson's disease, and that they potentiate the accumulation of α-synuclein protein.
Non-nearest-neighbor jumps in 2D diffusion: Pd on W(110).

A variety of jumps has in the past been identified in diffusion of atoms on ID channeled surfaces. To establish the jump processes important in diffusion on a 2D surface, the movement of individual Pd atoms has been examined on W( 110). From the distribution of displacements of Pd at high temperatures, double jumps are found along the close-packed . For the first time, sizable differences are also observed between the mean-square displacements along x and y, which demonstrate unexpected contributions from jumps along , but not along . These jumps proceed over activation barriers higher than for single jumps, under conditions predicted from previous work with Pd on the channeled W(211).
Nondimensional Parameters and Equations for Buckling of Anisotropic Shallow Shells

A procedure for deriving nondimensional parameters and equations for bifurcation buckling of anisotropic shallow shells subjected to combined loads is presented. First, the Donnell Mushtari Vlasov equations governing buckling of symmetrically laminated doubly curved thin elastic shallow shells are presented. Then, the rationale used to perform the nondimensionalization of the buckling equations is presented, and fundamental parameters are identified that represent measures of the shell orthotropy and anisotropy
Determination of Glutethimide, Aminoglutethimide, and Bemegride by Nonaqueous Titration

A simple nonaqueous titration procedure is presented for the determination of glutethimide, aminoglutethimide, and bemegride and their dosage forms. The solvent is dimethylformamide, and the titrant is sodium methoxide in benzene–methanol. By the proposed procedure it is possible to titrate differentially glutethimide and its degradation product, 4-ethyl-4-phenylglutaramic acid. Dosage forms are analyzed without preliminary extraction of the active constituent.
Regulation, counter-regulation, and immunotherapy of autoimmune responses to immunologically privileged retinal antigens

Our interests revolve around the study of biological mechanisms regulating self-tolerance to immunologically privileged retinal proteins that serve as targets in sight-threatening autoimmune uveitic disease. These studies are aimed at understanding how selftolerance to these antigens develops during ontogeny and is maintained during adulthood, the processes involved in its pathological breakdown, the regulatory mechanisms that bring about remission and recovery, and, finally, how we can utilize knowledge of these processes for therapeutic restoration of tolerance. To answer these questions, we use the experimental autoimmune uveitis (EAU) model in rats and mice. Because of the commonality of underlying immunological mechanisms, lessons and concepts learned in experimental ocular models are applicable to other disease entities, and, conversely, data gleaned from other autoimmune diseases are applicable to the study of uveitis.
University-based teleradiology in the united states

This article reviews the University of Arizona's more than 15 years of experience with teleradiology and provides an overview of university-based teleradiology practice in the United States (U.S.). In the U.S., teleradiology is a major economic enterprise with many private for-profit companies offering national teleradiology services (i.e., professional interpretation of radiologic studies of all types by American Board of Radiology certified radiologists). The initial thrust for teleradiology was for after-hours coverage of radiologic studies, but teleradiology has expanded its venue to include routine full-time or partial coverage for small hospitals, clinics, specialty medical practices, and urgent care centers. It also provides subspecialty radiologic coverage not available at smaller medical centers and clinics. Many U.S. university-based academic departments of radiology provide teleradiology services usually as an additional for-profit business to supplement departmental income. Since academic-based teleradiology providers have to compete in a very demanding marketplace, their success is not guaranteed. They must provide timely, high-quality professional services for a competitive price. Academic practices have the advantage of house officers and fellows who can help with the coverage, and they have excellent subspecialty expertise. The marketplace is constantly shifting, and university-based teleradiology practices have to be nimble and adjust to ever-changing situations.
Kapitza conductance of aluminium and heat transport through subcooled He II

Abstract Heat transport measurements in a large diameter tube containing He II are reported. The range of temperatures investigated are from 1.7 K to 2.1 K with applied pressures up to the critical pressure, 0.23 MPa. Temperature gradients established in the liquid are compared with previous experimental work and the theory of mutual friction. The Gorter-Mellink mutual friction constant, A, is observed to increase with applied pressure. At 2.01 K, a 0.1 MPa increase in pressure results in a 13.5 ± 4% enhancement of A. The results are used to predict the pressure and temperature dependence of the peak heat flux. Simultaneous measurements of the surface heat transfer from high purity aluminum to He II are reported. Kapitza conductance, film boiling and recovery heat flux data are analyzed and compared to other results on similar systems. A correlation is observed between the recovery heat flux and the film boiling heat transfer coefficient.
Ion bombardment-induced changes in the electronic structure of Cu(110) investigated with inverse photoemission and computer simulations

Abstract We have used the technique of inverse photoemission spectroscopy to investigate the changes in the surface state intensity of an unoccupied surface state on the clean Cu(1 1 0) surface due to Ne + ion bombardment of the surface. Using Monte Carlo simulations to model the sputtering process, we are able to determine the approximate surface cell size of 12×12 atoms that is required to support such a well-defined unoccupied surface state.
Attitudes of Undergraduate Students

Resume On a determine au moyen des Echelles des Attitudes de Thurstone les attitudes de 215 etudiants de derniere annee a l'Universite de Chicago a l'egard de la prohibition des liqueurs, de Dieu, du pacifisme, du communisme, et de la limitation de la natalite. Les etudiants se montrent opposes a la prohibition, favorablement disposes envers le pacifisme et la limitation de la natalite, et neutres a l'egard du communisme et de la realite de Dieu. Les etudiantes sont plus favorables a la prohibition, et croient plus fortement a la realite de Dieu que les etudiants. Les etudiants des sciences sociales favorisent un peu plus le communisme et le pacifisme que les etudiants des sciences physiques. Les etudiants juifs ont les attitudes les plus liberales a l'egard de ces questions sociales; les etudiants catholiques sont les moins liberaux, sauf a l'egard de la prohibition, a l'egard de laquelle les etudiants protestants sont les moins liberaux. L'intelligence ne montre aucune correlation avec l'attitude a l'eg...
The synthesis and characterization of zeolite A membranes

Abstract The application of dry gel synthesis procedures in the preparation of zeolite A membranes on α-alumina supports has been explored. With the dry gel method, the amount of initial gel applied to the support as well as the dilution of the initial gel may be used to directly control the amount of zeolite formed, and thus the thickness of the membrane. The results of these experiments show that the combination of dilute aqueous initial gel (1.35SiO 2 :Al 2 O 3 :5Na 2 O:1000H 2 O) with low temperature drying (298 K) yielded zeolite A membranes with small uniform crystals of size ∼0.2 μm. These membranes were characterized by single gas permeation and for gas separations with a mixture of butanes and neo-pentane. Neo-pentane, iso-butane and n-butane could not be separated directly. However, neo-pentane was completely excluded from the pore system by C6 adsorption (hexane or cyclohexane) prior to the permeation test and an n-butane/iso-butane separation factor of 2.3 was obtained.
The use of chloride based precursors in metalorganic vapor phase epitaxy

Abstract The expansion of device and materials concepts over the last decade was the result of accurate and controlled growth of epitaxial materials whose composition can be modulated on the monolayer level in the growth direction. The next advance in device structures will be due to the development of epitaxial techniques which also provide direct control over the lateral dimension of the structure. Selective epitaxy (SE) is a direct approach to forming such structures which extends this dimensional control during growth from a typically planar conformal deposition to the achievement of an arbitrary lateral definition down to the sub-micron level. Typical MOVPE growth, using compounds such as (CH 3 ) 3 Ga and (CH 3 ) 3 Al, is generally conformal in nature. The growth occurs on all surfaces which are greater than about 400°C. The use of halogen based precursors allow for SE over a wide range of growth conditions. The growth characteristics of GaAs and Al x Ga 1-x As based on halogenated metalorganics, such as (C 2 H 5 ) 2 GaCl and (C 2 H 5 ) 2 AlCl, are presented with an application to SE. The formation of small, sub-micron, SE hetero-structures has been demonstrated and is an early application of SE to the formation of laterally defined growth structures.
Quantification and Stratification: Wound Research in the Future

Advances in wound healing have been slow--from the realization of a concept through to its adoption into clinical practice. There are well-known and understood reasons for this conservative approach. One less well-tried thought is to stratify the patient's physiological status with regard to the wound. This may be the key to quantify changes in wound milieu and therefore to progress.
Agriculture and ground water quality: A public policy perspective

Agricultural production is an important source of ground water contamination in many regions of the U.S. Ground water contamination is the unintended side effect of actions by economic agents pursuing their interests within the legal framework established by current public policy. Under existing policy, agricultural producers do not have changes as noted to consider off-site effects of their decisions on ground water supplies. Given these policy rules, producers can be expected to cause such damage until their rights and obligations are adjusted by policy. The farmer is simply responding in a predictable manner to opportunities existing within the economic system. Possible rationales for government action to protect ground water quality include: 1) the existence of “third party” effects in the form of off-site damages associated with degraded water supplies; 2) overuse of an “open-access” resource; 3) society's desire to make conservative ground water management decisions to avoid the risks of contamination; and 4) individuals' demands for ground water protection even though they may not expect to directly benefit. Alternative policy instruments for ground water protection include taxes, subsidies, regulations and prohibitions, education, and public spending. Different policy approaches are being employed to address agricultural contamination of ground water. One policy approach emphasizes producers ' lack of accurate information and appropriate decision-making, and recommends educating farmers about how their profits can be increased by improved decisions regarding inputs. A second approach is to change the rules and incentives to compel or induce producers to act in a way that improves ground water quality. If ground water quality follows the pattern of most public issues, effective policies will be developed only as the cost of failing to act becomes known. Research and delivery of information on the costs of ground water protection and the costs of not protecting ground water are likely to be key factors affecting the formation of future ground water quality policies.
Damping characterization of viscoelastic composites using micromechanical approach

When studying composite material systems, mechanical properties, such as stiffness, strength, fracture toughness or damage resistance are the subjects of greatest interest and in most of the cases are considered in the context of simple static loading conditions. However, in almost all applications, composites, like most materials are subjected to dynamic loading which requires that the dynamic response of the composite be analyzed. For structural materials which are linear elastic, the stress-strain response is not dependent on strain rate, and there is no hysteresis or damping. However, this is not the case for viscoelastic materials for which both the stiffness and loss properties directly depend on strain rate and implicitly depend on temperature via time temperature superposition, which in case of harmonic loading leads to frequency dependent response. For viscoelastic composites in which at least one of the constituent materials is viscoelastic, there is great utility in the ability to predict the effective dynamic mechanical properties as a function of the constituent phase properties and geometry. In this paper micromechanical methods combined with the correspondence principle of viscoelasticity are used to obtain the effective damping properties of viscoelastic composites. When materials with different damping properties are present in a composite, the damping properties of the resulting composite are different than that of the constituents. The correspondence principle helps to consider all the frequency dependent properties of the constituent materials and conclude the effective damping vs. frequency. In this study the matrix phase is considered to be viscoelastic and spherical elastic/viscoelastic particles are dispersed into the matrix.
DNA binding by 4-methoxypyrrolic natural products. Preference for intercalation at AT sites by tambjamine E and prodigiosin

The 4-methoxypyrrolic natural products contain a common 4-methoxy-2,2'-bipyrrole chromophore and exhibit promising anticancer, antimicrobial, and immunosuppressive activities. Herein, the ability of two representative members, tambjamine E (1) and prodigiosin (2), to bind calf thymus DNA (CT-DNA), polyd[G-C](2), and polyd[A-T](2) has been characterized using absorption and fluorescence spectroscopy. Scatchard plots showed that 1 occupies a site size (n) of ca. three base pairs and possesses affinity constants (K) ranging from 1 to 0.1 x 10(5) M(-)(1). Prodigiosin (2) binds DNA by mixed modes, as isobestic points were not evident in titration experiments. The neutral aldehyde precursor 4 was found to possess no measurable DNA binding affinity, indicating that the enamine structure of 1 and the pyrromethene of 2 are essential elements for DNA binding affinity. The enamine of 1 was found to undergo hydrolysis to 4 with a half-life (t(1/2)) of 14.5 h at pH 7.4 and 37.5 degrees C. For the B-ring nitrogen atom of 1, a pK(a) value of 10.06 was also established. From fluorescence spectroscopy it was found that 1, 2, and 4 possess weak emission spectra in water that is increased in nonaqueous solvents. For 1 and 2, DNA binding also increased the emission yield. Energy-transfer measurements suggested an intercalative binding mode, with preference for AT sites. The ability of distamycin to displace 1 and 2 from the helix also suggested that they intercalate from the minor-groove. This specificity differs from other unfused aromatic cations that bind by a minor-groove mode at AT sequences and intercalate at GC sites. Reasons for the specificity displayed by 1 and 2, as well as the implications of our findings to their biological properties are discussed.
CANDIDATE ACTIVE NUCLEI IN LATE-TYPE SPIRAL GALAXIES

We have assembled a sample of 64 late-type spiral galaxies (T types 6.0-9.0, corresponding to Hubble types Scd-Sm) with archival Chandra data. At a signal-to-noise (S/N) threshold of 3, we find 12 objects with X-ray point-source detections in close proximity with the optical or near-infrared position of the nucleus (median offset δ = 16), suggestive of possible low-luminosity active galactic nuclei (AGNs). Including measurements with 3 > S/N > 1.5, our detections increase to 18. These X-ray sources range in luminosity from L X(2-10 keV) = 1037.1 to 1039.6 erg s–1. Considering possible contamination from low-mass X-ray binaries (LMXBs), we estimate that ~5 detections are possible LMXBs instead of true AGNs, based on the probability of observing an LMXB in a nuclear star cluster (NC) typically found in these late-type spiral galaxies. Given the typical ages of NCs, contamination by high-mass X-ray binaries is unlikely. This AGN fraction is higher than that observed in optical surveys, indicating that active nuclei, and hence central black holes (BHs), are more common than previously suggested. The incidence of AGN activity in such late-type spiral galaxies also suggests that nuclear massive BHs can form and grow in galaxies with little or no evidence for bulges. Follow-up multiwavelength observations will be necessary to confirm the true nature of these sources.
Developmentally sensitive assessment of social anxiety

Social anxiety affects children across the developmental spectrum. Early-onset social phobia may be particularly impairing because of its disruptive effects on social and academic functioning during a child's formative years and because of the elevated risks of childhood adversity in anxious individuals. Unfortunately, little attention has been paid to the early identification and assessment of social anxiety in young children. The ability to recognize and monitor or remediate social anxiety early in development would be of great advantage in reversing this potentially debilitating course. This article reviews various methods available to assess social anxiety and associated conditions. Particular emphasis is placed on the description and assessment of behavioral inhibition in infants and very young children as an early marker or precursor to the development of social anxiety. For school-aged children and adolescents, a greater range of assessment options is available including behavioral observation, clinician ratings, child self-report questionnaires, and parent and peer reports. In an effort to advance our understanding of the developmental psychopathology of social anxiety, further research is necessary to determine the equivalency of various assessment strategies across developmental periods.
Treatment of obesity as a potential complementary approach to cancer therapy

Obesity has long been recognized as a risk factor for diabetes and cardiovascular disease. Recent epidemiological data also associate obesity with cancer risk and progression. For this reason, a combination treatment of obesity along with treatment of the cancer itself may improve patient survival and well-being. As the molecular pathways linking obesity and cancer become better understood, new potential therapy targets are surfacing. In this article, we summarize the mechanisms proposed to account for the obesity–cancer association and discuss approaches to manipulation of adipose tissue as potential interventions aimed at cancer prevention or supplemental therapy.
Comparing MPEG AVC and SVC for adaptive HTTP streaming

Adaptive video streaming over HTTP is fast becoming a preferred way for delivering on-demand as well as live video service. The MPEG committee is finalizing a standard for Dynamic Adaptive Streaming over HTTP (DASH) and there is significant industry interest in this solution. DASH assumes/specifies MPEG AVC for content delivery. We analyze the use of MPEG scalable video coding (SVC) for adaptive streaming applications taking the end-to-end service delivery costs into consideration. Our models show that service delivery with SVC costs more and the costs may not outweigh the single bit stream representation and flexibility of SVC for most applications.
Effect of tongue exercise on protrusive force and muscle fiber area in aging rats.

Purpose Age-related changes in tongue function may contribute to dysphagia in elderly people. The authors' purpose was to investigate whether aged rats that have undergone tongue exercise would man...
Status of the NSF-Arizona AMS laboratory

Abstract The operation of the NSF-Arizona Laboratory is summarized. The methods used to determine accuracy and precision of radiocarbon measurements, and to make corrections for background contaminations are presented. An insulating support which has been installed, and a new heavy-ion beam line which is under construction, are described.
P40.01: Multislice display of the fetal face using 3D ultrasound

The test for pulmonary vascular reactivity in the fetus compares changes in branch pulmonary artery Doppler flow patterns with the mother breathing room air with maternal hyperoxygenation. A normal response to oxygen is to increase the pulmonary flow patterns and is seen in fetuses greater than 30 weeks’ gestation. Fetuses with severe growth restriction have redistribution of cardiac output to the brain, coronary and adrenal circulations. In fetuses greater than 30 weeks’ gestation with absent or reversed diastolic flow in the free loop of the umbilical artery and increased diastolic flow in the middle cerebral artery, the pulsatility of the flow in the branch pulmonary artery did not change with maternal hyperoxygenation. This indicates a fixed pulmonary vasoconstriction similar to what is seen in fetuses with pulmonary hypoplasia, yet these fetuses had normal respiratory function for gestational age after delivery. In fifteen fetuses hospitalized for growth less than 10% of prediction for age with abnormal umbilical artery Doppler flow patterns, the hyperoxygenation test was offered to mothers after obtaining consent. The results from these studies were compared to 15 fetuses whose mothers were hospitalized for pre-eclampsia, premature rupture of the membranes and abruption. Those fetuses whose growth biometry was within normal limits had normal pulmonary vascular response to the maternal hyperoxygenation test while those with severe growth restriction did not. Of those fetuses who had received antenatal steroids prior to the hyperoxygenation test, there was no effect on pulmonary vasodilatation in those with severe growth restriction but those fetuses with normal growth appeared to have an exaggerated positive response.
Calcium Oxalate-Crystal Membrane Interactions: Dependence on Membrane Lipid Composition

AbstractPurpose: Urolithiasis is clearly a multifaceted process, progressing from urine supersaturation to the formation of mature renal calculi. Retention of microcrystals by the urothelium is a critical event in stone maturation. Membrane phospholipids appear to be involved in the attachment of stone crystals to kidney epithelium.Materials and Methods: The current study quantitates crystal-membrane interactions following selective changes in the red blood cell (RBC) membrane phospholipid composition by using a crystal-induced membranolytic assay.Results: Membrane enrichment with anionic phospholipids was found to greatly increase crystal-membrane interactions. Crystal-membrane interaction was associated with an increase in the negative charge on the RBC membrane surface.Conclusions: Specific membrane compositions seem to facilitate the formation of a crystal attachment region on the RBC surface that is necessary for effective crystal attachment to the cell membrane.
Synthesis of methyl 16-trideuteriohexadecanoate☆

Abstract Methyl 16-trideuteriohexadecanoate has been prepared in high isotopic purity and in 29% overall yield, from methyl 7-oxo-16-heptadecenoate. The oxo group was reduced with sodium cyanoborohydride and the CD3 group was introduced by reduction with lithium aluminum deuteride, first of the ester group to the alcohol and then of the derived mesylate. The carboxyl group was formed by oxidative cleavage of the double bond.
Nanosecond fluorescence decay study of mitochondria and mitochondrial membranes

Summary The nanosecond fluorescence decay of the tryptophan residues of rat liver mitochondria and mitochondrial membranes has been measured. Apparent fluroescence lifetimes of 3 to 11 nanoseconds have been observed. Authentic membrane proteins suspended in 50% DMSO exhibit fluorescence properties almost identical to membrane proteins in situ . It is found that the fluorescent membrane components appear to remain firmly bound to the membranes in fresh preparations, but can be, at least in part, released into the solvent phase as a consequence of freeze thaw procedures.
Spectral analysis of the EEG recorded during stimulation of the human fovea.

Abstract Computer spectral analysis was performed on the EEGs of 6 subjects recorded during monocular foveal stimulation. Stimulus wavelength and subjective brightness were varied independently to determine their importance to changes in the ongoing EEG. The contribution of oculomotor control to these effects and the retinal area of their origin were also investigated. The major results were as follows. (1) Stimulation of the fovea reduced the amplitude of the EEG and the coherence between hemispheres at all frequencies, but most dramatically in the alpha band. (2) It increased the variance of EEG amplitudes and widths of spectral peaks in the alpha band and shifted these peaks to lower frequencies. (3) Auto-spectral intensities in the alpha band were enhanced slightly at brightness levels near photopic threshold, but were unaffected by changes in stimulus wavelength. (4) The fovea appeared to be the most effective retinal area in which irradiation attenuated ongoing alpha activity.
Quantitative trait loci controlling allergen-induced airway hyperresponsiveness in inbred mice.

Identification of the genetic loci underlying asthma in humans has been hampered by variability in clinical phenotype, uncontrolled environmental influences, and genetic heterogeneity. To circumvent these complications, the genetic regulation of asthma-associated phenotypes was studied in a murine model. We characterized the strain distribution patterns for the asthma-related phenotypes airway hyperresponsiveness (AHR), lung eosinophils, and ovalbumin (OVA)-specific serum immunoglobulin (Ig) E induced by allergen exposure protocols in A/J, AKR/J, BALB/cJ, C3H/HeJ, and C57BL/6J inbred strains and in (C3H/HeJ × A/J)F1 mice. Expression of AHR differed between strains and was sometimes discordant with lung eosinophils or serum IgE. Furthermore, we identified two distinct quantitative trait loci (QTL) for susceptibility to allergen-induced AHR, Abhr1 (allergen-induced bronchial hyperresponsiveness) (lod = 4.2) and Abhr2 (lod = 3.7), on chromosome 2 in backcross progeny from A/J and C3H/HeJ mice. In addition, a...
Gene expression imaging with radiolabeled peptides

An approach to image radiolabeled peptide localization at tumor sites by inducing tumor cells to synthesize membrane expressed human somatostatin receptor subtype 2 (hSSTr2) with a high affinity for radiolabeled somatostatin analogues is described. The use of gene transfer technology to induce expression of high affinity membrane hSSTr2 can enhance the specificity and degree of radiolabeled peptide localization in tumors. Employing this strategy, induction of high levels of hSSTr2 expression with selective tumor uptake of radiolabeled peptides was achieved in both subcutaneous non-small cell lung cancer and intraperitoneal ovarian cancer mouse human tumor xenograft models. The features of this genetic transduction imaging approach are: (1) constitutive expression of a tumor-associated receptor is not required; (2) tumor cells are altered to express a new target receptor or increased quantities of a constitutive receptor at levels which may significantly increase tumor targeting of radiolabeled peptides compared to uptake in normal tissues; (3) gene transfer can be accomplished by local or regional injection of adenoviral vectors; (4) it is feasible to target adenovirus vectors to tumor cells by modifying adenoviral tropism (binding) or by the use of tumor-specific promoters such that the hSSTr2 will be specifically expressed in the desired tumor; and (5) this technique can be used to image expression of a second therapeutic gene.