cssi/SciSciGPT-SciSciNet huggingface dataset:
Finite-element simulation of asymmetric folding

Abstract Fold shapes and strain distributions produced in stiff single layers inclined up to 20° to the direction of principal shortening were investigated using finite-element computer models. The finite-element model was formulated for constant-strain quadrilaterals using the constitutive equation for a compressible, linearly viscous fluid. The model of a stiff layer imbedded in a less viscous medium was designed to accommodate 2 1 2 Biot wavelengths. Inclinations of the stiff layer to the shortening direction were 0°, 5°, 10°, 15° and 20°. At each inclination folds were produced with viscosity ratios of 17 : 1, 24 : 1 and 42 : 1. Folds were initiated by prescribing symmetric sinusoidal perturbations with limb dips of 2°. Results from models with 0° initial inclinations are similar to results obtained by others. Folds are sinusoidal and symmetric, and strain distributions are symmetrically disposed about axial planes in both the matrix and stiff layer. As layer inclination is increased, these features change. The folds become asymmetric (as measured by the ratio of limb lengths), and the amount of asymmetry increases with inclination. Finite-strain distributions in both the stiff layer and matrix are not symmetrically disposed about the axial plane. Principal strains in the matrix tend to parallel the long limb of the stiff layer, and are “refracted” through the long limb at a larger angle than through the short limb.
Protocol for selecting an in‐tank leak detection device

A protocol has been developed to rank in‐tank detection devices for underground storage tanks. Eleven leak detection devices were selected and evaluated relative to 12 decision factors. The importance of the factors differs with environmental, physical and economic conditions, therefore, four hypothetical operating situations were used for evaluation. The unranked paired‐comparison technique was used to weight the decision factors. The ranking approach for the in‐tank detection was devices simplified by a categorization scheme. The resultant decision matrix indicates that the selection of a leak detection device should be based upon the operating conditions and choices among devices that satisfy regulations and decrease the possibility of user liability.
Phase separation to create hydrophilic yet non-water soluble PLA/PLA-b-PEG fibers via electrospinning

In moisture wicking fabrics, fibers with hydrophilic surfaces that are also non-water soluble are desirable. In poly(lactic acid), PLA, fibers it is expected that the addition of poly(ethylene glycol), PEG, will monotonically increase their wicking rates. In this paper, phase separation was used to create biocompatible, biodegradable, hydrophilic yet non-water soluble fibers by electrospinning PLA with PEG and PLA-b-PEG copolymers. By tuning the thermoelectric parameters of the apparatus, and the chemical properties of the dopes, the amount of PEG in the fibers was improved over prior work; concentration increased by 60% (by weight, wt %) to 16 wt % in the PLA fiber. Instead of the expected increasing wicking rates with PEG concentration, there is a peak at 12 wt %; at greater concentrations, wicking decreases due to PEG crystallization within the PLA (verified via DSC). At 12 wt % PEG from copolymers, the nanofabric's wettability increases to 1300% its original weight. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41030.
Field measurement and associated controlling factors for ground water seepage in a piedmont impoundment

Knowledge of groundwater seepage to and from lakes can be an important component of scientific investigations involving water and geochemical budgets. Measurements of groundwater seepage at Lake Anna, a man-made lake in central Virginia, show that inflow to the lake occurs even under dry summer conditions. Seepage rates were found to be correlated with the elevation of the near-shore water table, which responded rapidly to rainfall events in the fractured rock terrane in which Lake Anna is located. Seepage rates did not decline uniformly with distance offshore. This result contrasts with those for lakes underlain by relatively homogeneous porous media where measurements generally confirm the prediction that seepage rates drop off exponentially with distance from shore. The along shore variability of seepage rates in Lake Anna was related to a topographic index that is used to describe drainage from hillslopes. This suggests that seepage in impoundments such as Lake Anna may be strongly controlled by drainage pathways that pre-date the lake.
Aeroelastic stability of coupled flap-lag motion of hingeless helicopter blades at arbitrary advance ratios†

Equations for large amplitude coupled flap-lag motion of a hingeless elastic helicopter blade in forward flight are derived. Only a torsionally rigid blade excited by quasi-steady aerodynamic loads is considered. The effects of reversed flow together with some new terms due to radial flow are included. Using Galerkin's method the spatial dependence is eliminated and the equations are linearized about a suitable equilibrium position. The resulting system of homogeneous periodic equations is solved using multivariable Floquet-Liapunov theory, and the transition matrix at the end of the period is evaluated by two separate methods. Computational efficiency of the two numerical methods is compared. Results illustrating the effects of forward flight and various important blade parameters on the stability boundaries are presented.
Use of lasers for vision correction of nearsightedness and farsightedness

A 32-year-old woman with moderate myopia and mild dry eye has worn soft contact lenses for 12 years but now is not tolerating them well. On examination, her refraction is –4.25 + 1.0 × 90 (–3.75 diopters of spherical equivalent and 1 diopter of astigmatism at 90 degrees) in the right eye and –3.5 + 0.5 × 88 in the left eye, yielding a best corrected visual acuity of 20/20 in each eye. She asks about refractive surgery. What would you advise?
Radioanalytical approach to determine 238Pu, 239+240Pu, 241Pu and 241Am in soils

The simultaneous determination of multiple actinide isotopes in samples where total quantity is limited can sometimes present a unique challenge for radioanalytical chemists. In this study, re-determination of 238Pu, 239+240Pu, and 241Am for soils collected and analyzed approximately three decades ago was the goal, along with direct determination of 241Pu. The soils had been collected in the early 1970’s from a shallow land burial site for radioactive wastes called the Subsurface Disposal Area (SDA) at the Idaho National Lab (INL), analyzed for 238Pu, 239+240Pu, and 241Am, and any remaining soils after analysis had been archived and stored. We designed an approach to reanalyze the 238Pu, 239+240Pu, and 241Am and determine for the first time 241Pu using a combination of traditional and new radioanalytical methodologies. The methods used are described, along with estimates of the limits of detection for gamma-and alpha-spectrometry, and liquid scintillation counting. Comparison of our results to the earlier work documents the ingrowth of 241Am from 241Pu, and demonstrates that the total amount of 241Am activity in these soil samples is greater than would be expected due to ingrowth from 241Pu decay.
Structure-Property Relationship in Ionomer Membranes

Abstract Perfluorosulfonic acid (PFSA) ionomer membranes are ion-conducting polymers with high water sorption capacity and thermo-mechanical stability. The morphology of PFSA changes during sorption affecting the mechanical and physical properties of the membrane. In this work, we investigate the structure-property relationship in swollen PFSA membranes using three proposed nanostructural descriptions and determine Young's modulus of the membrane at a wide range of temperatures (−20–85 °C) and water volume fractions (0–0.5) for these configurations. Comparing the mechanics-based models with experimental data we propose that ion-rich water domains in PFSA membrane are spherical at low water content, spherical with connecting channels at intermediate water content and cylindrical at high water contents. Furthermore, our findings indicate that the scaling behavior for Young's modulus of PFSA ionomers is similar to that of aerogels. This suggests, from a mechanics perspective, that aerogels and ionomers may have a similar interconnected porous nanostructure where some solid regions do not contribute to the mechanical load-bearing capacity.
Nonoccluded, cytoplasmic virus particles and rickettsia-like organisms in testes and spermathecae of Diabrotica virgifera☆

Abstract An ultrastructural study was conducted on the testes and spermateca of adult Diabrotica virgifera virgifera that exhibited a high incidence of abnormal sperm. The cytoplasm of spermatocyst cells was found to contain large masses of 24 to 26-nm virus particles assembled in loose aggregates or in tightly packed crystalline arrays. Double-tailed and frayed sperm in various stages of disintegration were associated with the spermatocyst cells. Similar virus particles in crystalline arrays were found in spermathecal epithelial cells and in muscle cells associated with the spermatheca. The size and appearance of the particles suggest that the virus is a picornavirus. Rickettsia-like organisms (RLO) were abundant in spermatocyst cells in addition to virus particles. These organisms were ca. 0.6 μm in diameter and up to 2.7 μm in length and were found either singly or in various-sized aggregates. The RLOs were each surrounded by a double unit membrane and colonies composed of several individuals were enclosed within a cellular vacuolar membrane. Although the virus appears to be involved in the production of abnormal sperm, the RLOs appear to act as harmless symbionts as they were abundant in spermatocyst cells that were free of damaged sperm and were present in other tissues.
A novel approach to modeling the reaction kinetics of tetracycline antibiotics with aqueous ozone

Tetracycline antibiotics represent one of the most successful classes of pharmaceuticals and are extensively used around the world for human and veterinary health. Ozone-based processes have emerged as a selective water treatment process for many pharmaceuticals. The primary objective of this study was to determine the reaction kinetics for transformation of five tetracycline antibiotics (i.e., chlortetracycline, doxycycline, oxytetracycline, rolitetracycline, and tetracycline) by ozone across the pH2 to 9 range. The apparent second-order rate constant for tetracycline was on the order of 1-6 × 10(4) M(-1) s(-1) at low pH, and 0.6-2.0 × 10(6) M(-1) s(-1) at near neutral pH. The apparent second-order rate constants did not fit a conventional pKa-based model, presumably due to the complex acid/base speciation of tetracycline antibiotics. A model that considers the net charge on tetracycline molecules in solution provided a nice fit to experimental data for all five tetracyclines. The five tetracycline antibiotics demonstrated similar reaction kinetics with ozone, and a cumulative analysis of all kinetics data provides a baseline model for other tetracycline compounds. The ozone exposure required for complete transformation of tetracycline antibiotics (10(-5) M-s) is well below that achieved during ozone disinfection processes (10(-3) M-s), indicating that ozone is an effective treatment for tetracycline antibiotics.
κ Opioid receptor-mediated analgesia in the developing rat

Abstract The prototypic κ opiate ketocyclazocine produced robust analgesia in 10-day-old rats in the tail-flick nociceptive test. The κ-opiate behavioral response coincided with the onset of a rapid rise to adult levels in brain κ receptor site density. In contrast, morphine (prototypic μ opiate) was without marked effect until 14 days of age. The period of rapid μ receptor increase did not take place until days 14–16, which was after κ receptor levels had already plateaued. Further, there was no or incomplete cross-tolerance between ketocyclazocine and morphine at 14 days of age. The present study, therefore, establishes a role for the κ binding site in thermal analgesia in the tail flick test and differentiates its ontogenetic pattern from that of the μ receptor.
Development of one-cell ovine embryos in two culture media under two gas atmospheres.

The objective of this study was to develop a successful system for culturing one-cell ovine embryos through several cleavage divisions. One hundred and four one-cell embryos were collected from synchronized, FSH-treated ewes 48 hr after the onset of estrus and randomly placed in one of four culture treatments. The effect of glucose supplementation and reduced oxygen tension (20% vs. 5%) on embryo development was studied. Embryo development was quantitated by a cleavage index based on the number of completed cell divisions. The number of embryos completing at least two cell divisions when cultured in Brinster's Pyruvate Medium (BPM) was 7 26 and 9 26 , under 5% CO(2) in air and 90% N(2), 5% CO(2), 5% O(2), respectively, while 22 26 and 20 26 embryos divided when cultured in BPM supplemented with 0.1% glucose (BPM-G) under similar atmospheres. Mean cleavage indices for embryos cultured in BPM were 1.2 and 1.6 under 5% CO(2) in air and 90% N(2), 5% CO(2), 5% O(2), respectively, while embryos cultured in BPM-G had mean cleavage indices of 4.6 and 4.0, respectively. Results of this study indicate that one-cell ovine embryos can be successfully cultured through several cleavage divisions. Glucose supplementation was beneficial for one-cell ovine embryo development. Reducing the oxygen tension from 20 to 5% had no effect on embryo development, and there was no media x gaseous atmosphere interaction.
Age and relative importance of major life domains

Abstract Based on a quality of life conceptual model which incorporates the domain comparison process postulated by the self-system perspective, this study empirically examined the relationship between age and domain comparison among adults age 50 and above. Study participants were interviewed through telephone. Domain comparison was measured by asking the participants to rank eight major life domains, based on their importance. Data were analyzed using exploded logit regression models. Among the eight domains studied, the most important was health, followed by family life, religion, friendships, financial situation, spare time, neighborhood, and work. The results indicate that age is significantly associated with domain comparison, which provides preliminary support for the domain comparison process postulated by the self-system perspective.
Bender‐Gestalt performance of Puerto Rican, white, and Negro children

The Bender-Gestalt performance of 74 non-middle-class white and 47 non-middle-class Negro children was investigated in the first and third grades. The developmental lag found in the non-white children supported previous research findings that were generalized to include Puerto Rican children. The Bender was found to be a valid measure of developmental differences for the non-white groups, as already had been established for white populations. Although the Puerto Rican group caught up with the white group by the end of the third grade, the Negro group did not. The data suggested that the Koppitz norms may be too high in the middle range and not accurate when differences between scores are small.
Deformation of a planar sinusoidal elastic beam

The load-deformation curves of sinusoidal shaped elastic beams under tensile end loads with and without distributed loading along the beam proportional to the local displacements have been determined.
Is a silastic radial head still a reasonable option

The importance of the radial head to elbow function and stability is increasingly apparent. Although preservation of the native radial head is preferred, severely comminuted fractures may necessitate resection or arthroplasty. Silastic radial head arthroplasty has been condemned on the basis of several sporadic reports of silicone synovitis. However, problems of “overstuffing,” cartilage wear, and motion loss are becoming apparent with metal prostheses, indicating this also is not an ideal solution. Thus, the choices remain controversial. We asked whether intact or reconstructed primary elbow stabilizers permit use of silastic radial head implants without fragmentation, failure, and silicone synovitis. We retrospectively reviewed 23 patients with unreconstructable radial head fractures who were treated with silastic radial head arthroplasty and concomitant repair and/or reconstruction of the medial ulnar collateral ligament and/or lateral ulnar collateral ligament. Analysis included range of motion, pain, stability, and radiographic assessments; Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire; and Mayo Elbow Performance Score (MEPS). The minimum followup was 16 months (average, 69.6 months; range, 16-165 months). At last followup, the mean elbow flexion was 145°, extension 11°, supination 80°, and pronation 83°. The mean MEPS score was 88.9. The mean DASH score was 11.8. There were eight reoperations, none resulting from failure of the radial head implants. These results demonstrate silastic radial heads can be used with low complication rates and without evidence of synovitis when concomitant elbow ligament repair or reconstruction is performed. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Cooperativity in the interaction of glyceraldehyde 3-phosphate dehydrogenase with erythrocyte membranes.

Summary Glyceraldehyde 3-phosphate dehydrogenase binding to the membrane of the human erythrocyte is affected by pyridine nucleotide coenzymes. At concentrations of NAD+ up to 1.7 mM, 90 per cent of the enzyme remains bound to the membrane in the presence of β-mercaptoethanol. However, NADH at 200 μM elutes all the enzyme from the membrane. In the presence of low concentrations of NAD+ the NADH elution curve becomes markedly sigmoid. At 50 μM NAD+ the Hill constant for elution of the enzyme from the membrane by NADH is 1.9. Positive cooperativity suggests that regulation of the enzyme-membrane interaction may have an important physiological role.
Relationship between the dynamic softening transition and wet sliding friction of elastomer compounds

For properly chosen elastomer compounds, thermorheological characterization is combined with an examination of the variation of the wet sliding friction with temperature. A conceptual argument leads to the assumption that the wet sliding friction should maximize at the energy dissipation peak associated with the dynamic softening transition at a characteristic frequency determined by the sliding speed and the effective smallest surface asperity scale. The dynamic softening transition is characterized with the peak in tan δ/G' n , where tan δ is the loss tangent, G' is the elastic modulus, and n is a constant between 0 and 1. The William-Landel-Ferry transform is uncritically applied for extrapolating the position of the peak in tan δ/G' n at high frequencies. Even based on the criterion of tan 8, the results obtained on a concrete surface indicate that the effective smallest asperity scale is of order of 100 μm.
Overview of damped least-squares methods for inverse kinematics of robot manipulators

In this paper, we present a tutorial report of the literature on the damped-least squares method which has been used for computing velocity inverse kinematics of robotic manipulators. This is a local optimization method that can prevent infeasible joint velocities near singular configurations by using a damping factor to control the norm of the joint velocity vector. However, the exactness of the inverse kinematic solution has to be sacrificed in order to achieve feasibility. The damping factor is an important parameter in this technique since it determines the trade-off between the accuracy and feasibility of the inverse kinematic solution. Various methods that have been proposed to compute an appropriate damping factor are described. Redundant manipulators, possessing extra degrees of freedom, afford more choice of inverse kinematic solutions than do non-redundant ones. The damped least-squares method has been used in conjunction with redundancy resolution schemes to compute feasible joint velocities for redundant arms while performing an additional subtask. We outline the different techniques that have been proposed to achieve this objective. In addition, we introduce an iterative method to compute the optimal damping factor for one of the redundancy resolution techniques.
The indeterminacy of prices under interest rate pegging: The non-Ricardian case

Abstract This paper investigates the issue of price level indeterminacy under a pure interest rate peg in models that depart from standard Ricardian assumptions. Using a monetary version of Blanchard's finite horizons model, I find wealth effects operating on government bonds are not sufficient to determine a unique price level. Next, I consider price determination under a non-Ricardian fiscal authority. I show that, if agents rationally perceive the possibility of fiscal default, the price level is again indeterminate. I conclude that departures from Ricardian equivalence are not sufficient to ensure a unique price level under a monetary policy of pure interest rate pegging.
Antioxidant and Anti-Inflammatory Role of Paraoxonase 1: Implication in Arteriosclerosis Diseases

Paraoxonase 1 (PON1) is a hydrolytic enzyme with wide range of substrates, and capability to protect against lipid oxidation. Despite of the large number of compounds that can be hydrolyzed by paraoxonase, the biologically relevant substrates are still not clearly determined. There is a massive in vitro and in vivo data to demonstrate the beneficial effects of PON1 in several atherosclerosis-related processes. The enzyme is primarily expressed in liver; however, it is also localized in other tissues. PON1 attracted significant interest as a protein that is responsible for the most of antioxidant properties of high-density lipoprotein (HDL). Several bioactive molecules such as dietary polyphenols, aspirin and its hydrolysis product salicylate, are known to stimulate PON1 transcription activation in mouse liver and HepG2 cell line. Studies on the activity, function, and genetic makeup have revealed a protective role of PON1. Some striking data were obtained in PON1 gene knockout and PON1 transgenic mouse models and in human studies. The goal of this review is to assess the current understanding of PON1 expression, enzymatic and antioxidant activity, and its atheroprotective effects. Results from in vivo and in vitro basic studies; and from human studies on the association of PON1 with coronary artery disease (CAD) and ischemic stroke will be discussed.
Effects of an i.v. lethal dose of 3,4-methylenedioxyamphetamine (MDA) in the dog and antagonism by chlorpromazine.

Abstract 1. 1. A high intravenous (i.v.) dose of MDA (20 mg/kg) to mongrel dogs elevated body temperature, heart rate, mean arterial pressure and other cardiovascular parameters initially, but only the 1st two remained high. Other functions soon became quite depressed, and death shortly ensued. 2. 2. Arterial pO 2 decreased, but pH and pCO 2 showed a biphasic response after an initial decrease, 3. 3. Dogs that received chlorpromazine (10 mg/kg, i.v.) after MDA showed stabilization of physiological parameters, and survival through 48 hr.
Distribution of lysozyme and mucin (MUC2 and MUC3) mRNA in human bronchus.

Immunocytochemical studies have shown that gel-forming glycoproteins (mucins) and the bacteriolytic protein lysozyme are selectively expressed in airway mucous and serous cells, respectively. The mechanisms mediating this selectivity are unknown. In this study, we localized mucin and lysozyme mRNA by in situ hybridization to investigate the possibility that phenotype-specific expression of these proteins is controlled at the level of mRNA. Radiolabelled sense and antisense probes were constructed from the human tracheal mucin cDNA, HAM1 (MUC2 gene), the human small intestinal mucin cDNA, SIB139 (MUC3 gene), and the bovine tracheal lysozyme cDNA, Lys 7a. Frozen sections of human bronchus were hybridized with these probes and washed under routine conditions. Autoradiography showed that although lysozyme mRNA was strictly limited to cells expressing lysozyme, mucin mRNA was present both in mucin-expressing and mucin–non-expressing epithelial cells. This suggests that the restriction of lysozyme to serous cel...
Unusual long term follow-up of xanthogranulomatous pyelonephritis by computed tomography: Case report

An unusual case of xanthogranulomatous pyelonephritis which had a 3 year follow-up is presented. Lack of perirenal extension probably accounted for its relatively asymptomatic course.
Optimization techniques for a high level synthesis implementation of the Sobel filter

For many application-specific computations, FPGA-based computing systems have been shown to provide superior performance per Watt than many general-purpose architectures. However, the benefits of FPGA-based computing are difficult to exploit since FPGAs are challenging to program and require advanced hardware design skills. Recent developments in High Level Synthesis (HLS) provide the ability to create FPGA compute accelerators entirely in `C' code. Because the circuits are described in `C', it may be possible for software programmers to “program” FPGA accelerator circuits. This paper explores the challenges faced by software programmers when using HLS to implement computing kernels within FPGAs and identifies the specific new knowledge and skills required by these programmers to succeed at the task. A high-performance Sobel edge-detection acceleration core is developed and used to demonstrate the use of the Vivado HLS tool. A variety of simple directives and code restructuring steps are applied to demonstrate a variety of Sobel edge-detection accelerators that vary in performance from 10.9 frames per second (fps) to 388 fps. The concepts outlined in this paper suggest that with proper training, software programmers are able to create a wide range of FPGA acceleration circuits.
Interpreting and conserving the openland habitats of coastal New England: insights from landscape history

Abstract Maintenance and restoration of grasslands, heathlands, and shrublands are high priorities for conservation due to their diversity of uncommon species and assemblages and their ongoing decline resulting from invasion by shrubs and trees. Much of the literature and management concerning openlands emphasizes burning to control woody growth, based on the interpretation that these habitats and their species assemblages were widespread during the pre-European period as a consequence of natural disturbance and Native American land use. By focusing on the coastal region of New England–New York, which harbors excellent examples of these habitats, is characterized by many natural disturbances (e.g. hurricanes, fire, salt spray), and supported relatively dense Native American populations, we assess the paleoecological, archaeological, historical, and modern ecological evidence supporting this perspective. We conclude that: (1) pre-European uplands, including coastal areas, were predominantly forested and that openland habitats were uncommon because natural and human disturbance was infrequent and local; (2) extensive openland vegetation developed only with widespread European forest clearance and land use; (3) assemblages occupying grasslands, shrublands, and heathlands apparently have no lengthy history and are comprised of species that combined opportunistically over recent centuries; (4) the decline of grasslands, heathlands, and shrublands is a century-old phenomena related to a decline in agricultural land use, especially grazing, mowing, plowing and burning; (5) effectively all conservation areas supporting these openland assemblages experienced intensive historical land use; and (6) the modern distribution, composition, and structure of these habitats are largely determined by European land use. Recognition that openland assemblages have cultural origins does not diminish the biological, cultural, or aesthetic value of these habitats. However, it does suggest that grasslands, heathlands and shrublands may be best managed using a combination of approaches that replicate the effects of historical land use. Conservationists should recognize that most of these landscapes have cultural origins and are inherently dynamic; that some vegetation structures and communities cannot be maintained continuously on a given site; and that management is most effective when based on historical and ecological studies leading to clearly defined objectives and rigorous long-term measurement and re-evaluation.
The application of X-ray diffraction measurements in the growth of LPE InGaAsP/InP

Abstract An important property of an InGaAsP epitaxial layer is the amount of lattice constant mismatch with respect to the InP substrate. X-ray diffraction is a powerful method of determining this parameter. The measuremnent of lattice mismatch has been used to understand and characterize the liquid phase epitaxial (LPE) growth of the InGaAsP quaternary alloy. The growth parameters — melt composition, growth temperature, temperature-time program, and intentional dopants — have all been found to influence the degree of mismatch. With this information the crystal growth conditions can be optimized to produce lattice matched layers of high quality.
Environmental advocacy in Washington: a comparison with other interest groups

Abstract Environmental organisations in Washington are one sector of a larger interest group community, but environmental advocacy is typically studied independently. Descriptive and comparative analysis of 92 Washington environmental organisations and more than 1,600 other advocacy organisations reveals that the structure and behaviour of environmental groups is typical of constituency interest organisations and differs in only a few systematic ways. On average, environmental organisations are better staffed than other groups and more likely to be actively involved in the courts. Yet in most respects, environmental representation matches the broader patterns of organised interest advocacy in Congress, the administration, and the media.
Melting of Poly(oxyethylene) Analyzed by Temperature-Modulated Calorimetry

Recently a small amount of locally reversible melting was observed in semicrystalline poly(ethylene terephthalate) during temperature-modulated differential scanning calorimetry (TMDSC). To further study the reversibility of melting, poly(oxyethylene) (POE) is analyzed. Low molar mass POE is known to be able to form extended-chain, equilibrium crystals, while at higher molar mass and less favorable crystallization conditions, nonequilibrium, folded-chain crystals grow. The TMDSC of POE reveals variable amounts of reversible melting depending on crystallization conditions and molar mass. The crystals closest to equilibrium show no reversible melting, proving the inherently irreversible nature of polymer melting. Crystals of high molar mass show a small amount of the prior discovered locally reversible melting. Poorly crystallized POE of low molar mass have, because of their lower zero-entropy-production melting temperature, a sufficiently smaller gap between crystallization and melting temperature to show ...
Social influences on estrogen excretion and ovarian cyclicity in saddle back tamarins (Saguinus fuscicollis)

The effects of different social living conditions on estrogen excretion and on the ovarian cycle of saddle back tamarins were investigated. Urinary estrogens were monitored as indices of ovarian cyclicity in groups of adult females living under the following experimental conditions: (1) five parous females, each living with an adult castrated male (in one of the females plasma estradiol and progesterone were also measured); (2) five adult daughters living with their families. Each daughter was then removed from her family and paired with a vasectomized male. After pairing, scent marks collected from the family were introduced daily to one of the daughters and her mate. Scent exposure was then discontinued and hormone excretion measured for several weeks. The remaining four daughters were not exposed to family scent. The females living with castrated males showed urinary estrogen cycles of an average length of 17.5 ± 1.0 days. The plasma estrogen cycle was of the same length. The females studied under condition 2 showed low, noncycling estrogen levels while living in their families. They responded to pairing with an increase in the level of urinary estrogens, and four out of five showed regular estrogen cyclicity. The fifth female exposed to family scent marks after pairing also showed an increase in urinary estrogens. However, as long as scent transfer was maintained, no cycle was observed. Estrogen excretion increased again, and cyclicity commenced when scent transfer was discontinued. It is concluded that ovarian estrogen production is suppressed and cyclicity does not occur as long as daughters live in their families. Release from suppression and perhaps stimulation by the male cause a rapid increase in estrogen levels and the onset of cyclicity. Chemical stimuli produced by the family, perhaps particularly by the mother, may be involved in reproductive suppression.
Surface Spectroscopic Examination of Diesel Particulates—A Preliminary Study

Abstract Preliminary studies on the use of combined surface analytical techniques such as X-ray Photoelectron Spectroscopy (XPS or ESCA). Auger Electron Spectroscopy (AES), Secondary Ion Mass Spectrometry (SIMS) and Ion Scattering Spectrometry (ISS) to probe the surfaces of diesel particulates are presented. Studies of two different particulate systems are reported. Results of the first study show common chemical forms associated with the surface of particulate emission. Oxygen, sulfur and nitrogen in various chemical states are seen on the surface of a carbonaceous-graphitic (pyrolytic) center. These elements are postulated as organically bound surface segregated species. Observation of particles extracted for routine adsorbed organic analysis by gas chromatography show that nitrogen and sulfur compounds are left behind, along with residual organics. Trace metals were not seen on any sample. The second study involves samples collected under different running speed conditions of a diesel engine. Typical a...
The Integrase of the Long Terminal Repeat-Retrotransposon Tf1 Has a Chromodomain That Modulates Integrase Activities

Chromodomains in a variety of proteins mediate the formation of heterochromatin by interacting directly with histone H3, DNA, or RNA. A diverse family of long terminal repeat (LTR)-retrotransposons possesses chromodomains in their integrases (IN), suggesting that the chromodomains may control integration. The LTR-retrotransposon Tf1 of Schizosaccharomyces pombe is highly active and possesses a chromodomain in the COOH terminus of its IN. To test this chromodomain for a role in integration, recombinant INs with and without the chromodomain were assayed for activity in in vitro reactions. The full-length IN had integration activity with oligonucleotide substrates that modeled both the insertion reaction and a reverse reaction known as disintegration. The INs of retroviruses possess an additional activity termed 3' processing that must remove 2-3 nucleotides from the 3' ends of the viral cDNA before insertion can occur. These additional nucleotides are added during reverse transcription because of the position of the minus strand primer downstream of the LTR. The position of the primer for Tf1 suggests no nucleotides are added 3' of the LTR. It was therefore surprising that Tf1 IN was capable of 3' cleavage. The most unexpected result reported here was that the IN lacking the chromodomain had significantly higher activity and substantially reduced substrate specificity. These results reveal that both the activity and specificity of enzymes can be modulated by their chromodomains.
Neuroimaging-Use Trends in Nonacute Pediatric Headache Before and After Clinical Practice Parameters

OBJECTIVES. The objective of this study was to determine trends in diagnostic neuroimaging-use rates in nonacute pediatric headache before and after publication of clinical practice guidelines. METHODS. Retrospective, cross-sectional analysis was conducted of neuroimaging rates for 725 children and adolescents who were aged 3 to 18 years with nonacute headache and normal neurologic examination and were evaluated in a single pediatric neurology clinic during study years 1992, 1996, 2000, and 2004. Following recommendations of current practice parameters, patients with conditions that justify consideration for neuroimaging (eg, progressive headache, abnormal neurologic examination) were excluded from this analysis. We recorded the origin of any neuroimaging request at the time of the clinic visit and any abnormal neuroimaging findings that led to major clinical consequences. RESULTS. Overall, the mean rate of neuroimaging for patients with nonacute headache was 45%. Use rates remained steady during the 13-year study period (range: 41%–47%). The majority of neuroimaging studies were ordered originally by primary care providers. The proportion of neuroimaging studies that were ordered by primary care providers increased significantly from 1992 to 2004. CONCLUSIONS. In the evaluation of patients who had nonacute pediatric headache and were referred to a child neurology clinic, neuroimaging-use rates remained stable during the past decade. An increasing proportion of neuroimaging studies are ordered by primary care providers. The influence of evidence-based medicine on medical decision-making may be partly responsible for curbing increases in neuroimaging overuse. The perceived value of neuroimaging by physicians and consumers deserves ongoing study.
Management of rostral mandibular fractures in the young horse

Summary Rostral mandibular fractures in the young horse can, in the majority of cases, be managed satisfactorily in the field. A technique for the field assessment and repair of such injuries is described here.
Expression and role of the universal stress protein, UspA, of Escherichia coli during growth arrest

Summary The synthesis of the smail, cytopiasmic protein UspA universal stress protein A) of Escherichia coli is induced as soon as the ceii growth rate faiis beiow the maximai growth rate supported by the medium, regardless of the condition inhibiting growth. The increase in UspA synthesis appears to be the resuit of Induction of the monocistronic uspA gene. Induction of this gene during a heat-shock treatment is demonstrated to be the resuit of transcription ai activation of a o'°-dependent promoter which has previousiy been shown to be activated aiso during carbon starvation-induced growth arrest. iVIutant ceiis lacking UspA grow at rates indlstinguisibie from the isogenic parent at different temperatures and in the presence of different growth inhibitors but are impaired In their abiiity to survive proionged periods of compiete growth inhibition caused by a variety of diverse stresses, inciuding CdCi2, H2O2, DNP, CCCP exposure, and osmotic shock. Moreover, the uspA mutation resuits in an increased sensitivity of ceiis to carbon-source starvation (i.e. glucose, giyceroi or succinate depletion). Aiso, the mutation causes a marked aiteratlon in the timing of starvation protein expression but protein expression during steadystate growth appears to be normal. The results presented have prompted us to postulate that UspA may have a general protective function related to the growth arrest state.
Personality and EQ-5D scores among individuals with chronic conditions.

Background Personality is associated with self-rated health, but prior studies have not examined associations with preference-based measures. We hypothesized similar associations would exist with preference-based health.
Preoperative chemoradiation, pancreaticoduodenectomy, and intraoperative radiation therapy for adenocarcinoma of the pancreatic head*

Background Local recurrence in the bed of the resected pancreas is the most common site of tumor recurrence following a standard pancreaticoduodenectomy (PD) for adenocarcinoma of the pancreatic head. In an attempt to improve local and regional disease control and thereby enhance the quality and length of survival in patients undergoing potentially curative PD, we have used a protocol of preoperative multimodality therapy. Ptients and methods All patients were treated with external-beam radiation (30.0 or 50.4 Gy) and concomitant 5-fluorouracll (300 mg/m 2 per day) prior to PD. Electron-beam intraoperative radiation therapy was given to the bed of the resected pancreas before reconstruction. Patients were assessed for recurrence by physical examination, chest roentgenography, and computed tomography scan performed at 3-month Intervals following treatment. Results Thirty-nine patients completed all therapy; 1 perioperative death occurred. Thirty-eight tumor recurrences have been documented in 29 patients at a median of 11 months from the date of diagnosis; 23 patients died of disease. The liver was the most frequent site of recurrence, and liver metastases were a component of treatment failure in 53% of patients. Isolated local or peritoneal recurrences were documented in only 4 patients (11%). The only significant clinical or pathologic variable predictive of local-regional recurrence was a previous laparotomy and intraoperative biopsy. The median survival of all 39 patients was 19 months, and the 4-year actuarial survival rate was 19%. Conclusions Preoperative Chemoradiation, PD, and electron-beam intraoperative radiation therapy for adenocarcinoma of the pancreatic head have resulted in improved local-regional tumor control, with distant metastatic disease becoming the predominant site of tumor recurrence. Future treatment stategies should incorporate effective multimodality therapy for local-regional disease as demonstrated in this study. Major improvements in overall survival will likely await the development of systemic or regional therapy for liver metastases.
A role for ion channels in glioma cell invasion.

Many cells, including neuronal and glial progenitor cells, stem cells and microglial cells, have the capacity to move through the extracellular spaces of the developing and mature brain. This is particularly pronounced in astrocyte-derived tumors, gliomas, which diffusely infiltrate the normal brain. Although a significant body of literature exists regarding signals that are involved in the guidance of cells and their processes, little attention has been paid to cell-shape and cell-volume changes of migratory cells. However, extracellular spaces in the brain are very narrow and represent a major obstacle that requires cells to dynamically regulate their volume. Recent studies in glioma cells show that this involves the secretion of Cl− and K+ with water. Pharmacological inhibition of Cl− channels impairs their ability to migrate and limits tumor progression in experimental tumor models. One Cl−-channel inhibitor, chlorotoxin, is currently in Phase II clinical trials to treat malignant glioma. This article reviews our current knowledge of cell-volume changes and the role of ion channels during the migration of glioma cells. It also discusses evidence that supports the importance of channel-mediated cell-volume changes in the migration of immature neurons and progenitor cells during development. New unpublished data is presented, which demonstrates that Cl− and K+ channels involved in cell shrinkage localize to lipid-raft domains on the invadipodia of glioma cells and that their presence might be regulated by trafficking of these proteins in and out of lipid rafts.
A simulation study of schemes for block loss reduction in ATM networks using FEC and buffer management

Traditional approaches to guaranteeing quality-of-service (QoS) in ATM networks have focused on performance metrics such as cell loss probability, end-to-end cell delay and delay jitter. However, the block loss rate is a more meaningful metric for applications such as medical imaging and real-time video, and for high-level protocols such as IP which will use ATM as the transport mechanism. A block is defined as a group of consecutive ATM cells. A block loss occurs when a single cell from a block is lost. We propose and evaluate, via extensive simulation, a technique for reducing block loss in ATM networks. Our method combines two well-studied approaches for minimizing the impact of information loss during transport over ATM networks which have been considered independently of each other in the past: priority-based cell discarding and forward error correction (FEC). We also study an enhanced buffer management algorithm which we call adaptive pushout (ADP) that accounts for correlations between cell losses. The ADP algorithm reduces block loss rates to near-optimal levels. We consider further performance enhancements to the ADP policy that deliver excellent performance even under very heavy load.
SCUBA: focus and context for real-time mesh network health diagnosis

Large-scale wireless metro-mesh networks consisting of hundreds of routers and thousands of clients suffer from a plethora of performance problems. The sheer scale of such networks, the abundance of performance metrics, and the absence of effective tools can quickly overwhelm a network operators' ability to diagnose these problems. As a solution, we present SCUBA, an interactive focus and context visualization framework for metro-mesh health diagnosis. SCUBA places performance metrics into multiple tiers or contexts, and displays only the topmost context by default to reduce screen clutter and to provide a broad contextual overview of network performance. A network operator can interactively focus on problem regions and zoom to progressively reveal more detailed contexts only in the focal region. We describe SCUBA's contexts and its planar and hyperbolic views of a nearly 500 node mesh to demonstrate how it eases and expedites health diagnosis. Further, we implement SCUBA on a 15-node testbed, demonstrate its ability to diagnose a problem within a sample scenario, and discuss its deployment challenges in a larger mesh. Our work leads to several future research directions on focus and context visualization and efficient metrics collection for fast and efficient mesh network health diagnosis.
Materials research and applications at NASA Lewis Research Center

The facilities and instruments of the Lewis Research Center specialized for materials research are discussed. The main objectives of the Center are to provide R & D relevant to main propulsion plants and auxiliary power systems for aeronautics, space, and energy conversion applications. The Center is concerned with microstructure-property relations and their effect on processing; intermetallic compounds and high temperature metal matrix composites; ceramics with improved reliability for use in heat engines; polymer matrix composites for aerospace applcations; understanding the high temperature corrosive attack in the hostile environments of aircraft, rockets, and other heat engines; high temperature lubrication and wear; and microgravity materials research. The various types of schemes and techniques, provided by the Center, for analyzing data are described.