cssi/SciSciGPT-SciSciNet huggingface dataset:
Antinociceptive effect of systemic and intrathecal morphine in spinally transected rats

The antinociceptive effect of morphine on the tail withdrawal reflex was examined in spinally transected rats. The efficacy of systemically administered morphine was significantly reduced within 24 h after transection, and continued to decline during the first three posttransection weeks. In contrast to the diminished effect of systemic morphine, the efficacy of intrathecal morphine was not reduced during the first three weeks after a spinal transection. These data demonstrate a significant difference in the functional effect of systemic and spinal morphine in spinally transected rats. The results indicate that the direct antinociceptive effect of morphine on the spinal cord is not reduced after spinal transection.
Mechanics of Active Contraction in Cardiac Muscle: Part II—Cylindrical Models of the Systolic Left Ventricle

Models of contracting ventricular myocardium were used to study the effects of different assumptions concerning active tension development on the distributions of stress and strain in the equatorial region of the intact left ventricle during systole. Three models of cardiac muscle contraction were incorporated in a cylindrical model for passive left ventricular mechanics developed previously [Guccione et al. ASME Journal of Biomechanical Engineering, Vol. 113, pp. 42-55 (1991)]. Systolic sarcomere length and fiber stresses predicted by a general "deactivation" model of cardiac contraction [Guccione and McCulloch, ASME Journal of Biomechanical Engineering, Vol. 115, pp. 72-81 (1993)] were compared with those computed using two less complex models of active fiber stress: In a time-varying "elastance" model, isometric tension development was computed from a function of peak intracellular calcium concentration, time after contraction onset and sarcomere length; a "Hill" model was formulated by scaling this isometric tension using the force-velocity relation derived from the deactivation model. For the same calcium ion concentration, the sarcomeres in the deactivation model shortened approximately 0.1 microns less throughout the wall at end-systole than those in the other models. Thus, muscle fibers in the intact ventricle are subjected to rapid length changes that cause deactivation during the ejection phase of a normal cardiac cycle. The deactivation model predicted rather uniform transmural profiles of fiber stress and cross-fiber stress distributions that were almost identical to those of the radial component. These three components were indistinguishable from the principal stresses. Transmural strain distributions predicted at end-systole by the deactivation model agreed closely with experimental measurements from the anterior free wall of the canine left ventricle.
A Coupled FEM/BEM for Fluid-Structure Interaction Using Ritz Vectors and Eigenvectors

In this paper, the finite element (FEM) and the boundary element method (BEM) are combined together to solve a class of fluid-structure interaction problems. The FEM is used to model the elastic structure and the BEM is used to model the acoustic fluid. Quadratic isoparametric elements are used in both the FEM and BEM models. Continuity conditions of pressure and normal velocity are enforced at the fluid-structure interface on which the normal vector is not required to be uniquely defined. An enhanced CHIEF formulation is adopted to overcome the nonuniqueness difficulty at critical frequencies. To reduce the dimension of the coupled structural acoustic equations, the structural displacement is approximated by a linear combination of either Ritz vectors or eigenvectors. An error norm and a participation factor are defined so that it is possible to evaluate the accuracy of a solution and to omit vectors with small participation factors. Example problems are solved to examine the accuracy of the numerical solutions and to compare the efficiency of the Ritz vector and eigenvector syntheses.
Discovering the Targets of Drugs Via Computational Systems Biology

Computational systems biology is empowering the study of drug action. Studies on biological effects of chemical compounds have increased in scale and accessibility, allowing integration with other large-scale experimental data types. Here, we review computational approaches for elucidating the mechanisms of both intended and undesirable effects of drugs, with the collective potential to change the nature of drug discovery and pharmacological therapy.
Conceptual Stress and Conceptual Strength for Functional Design-for-Reliability

Stress and Strength Interference Theory (SSIT) is a fundamental theory for reliability assessment. It has been widely used as a foundation for design-for-reliability (DFR). However, SSIT and associated methodology and tools, that require detailed definitions of constructional and form structure, are only applicable to an embodiment design. As many researchers have attempted to push DFR upfront to a conceptual and functional design stage, SSIT loses its usefulness, while other equivalent theory and tools for conceptual and functional design-for-reliability do not exist. Therefore, DFR for conceptual and function design becomes ad-hoc that lacks a systematic approach and parametric reliability quantification. In this paper, we first review the literature on stress and strength interference, and then extend the concepts of stress and strength to conceptual stress and conceptual strength that are relevant to conceptual and functional designs. Based on the conceptual stress and conceptual strength, we introduce a Conceptual Stress and Conceptual Strength Interference Theory (CSCSIT) and discuss how it can be applied to support conceptual and function design-for-reliability. We illustrate our theoretical work with a conceptual and function design example. We conclude the paper with a discussion of the future research to further define and substantiate the CSCSIT work.Copyright © 2008 by ASME
Theory of the modified two-stream instability in a magnetoplasmadynamic thruster

It is shown that for plasma parameters characteristic of those found in magnetoplasmadynamic (MPD) thrusters the modified two-stream instability may exist in the plasma. The critical parameter for triggering this instability is the ratio of the crossfield current to the ion saturation current. Once triggered, this instability greatly increases the plasma resistivity to the flow of the current and heats both ions and electrons. The anomalous momentum-exchange frequency and heating rates are calculated for characteristic MPD thruster parameters. 17 refs.
Efficient pressure estimation in molecular simulations without evaluating the virial

A method for calculating the pressure in molecular simulations that does not require calculation of the virial is proposed, building on earlier work by [R. Eppenga and D. Frenkel, Mol. Phys. 52, 1303 (1984)]. The method requires ‘‘test’’ volume changes and it is particularly efficient for ensembles demanding volume fluctuations, such as the Gibbs ensemble. The method is validated by calculating the pressure in Gibbs ensemble simulations for monoatomic and polyatomic fluids.
One-step green route to narrowly dispersed copper nanocrystals

We report a total “green” chemical method in aqueous solution for synthesizing stable narrowly distributed copper nanoparticles with average diameter less than 5 nm in the presence of Polyvinylpyrrolidone (PVP) as a stabilizer and without any inert gas protection. In our synthesis route, ascorbic acid, natural vitamin C (VC), an excellent oxygen scavenger, acts as both reducing agent and antioxidant, to reduce the metallic ion precursor, and to effectively prevent the common oxidation process of the newborn pure copper nanoclusters.
STUDIES FOLLOWING INTRAMUSCULAR TRITIATED DIGOXIN IN HUMAN SUBJECTS.

Abstract Ten patients were digitalized by the intramuscular route with tritium-labeled digoxin. Radioactivity levels of the serum, urine and stools were studied for seven days. Serum digoxin radioactivity is present in 5 minutes, rises slowly to a peak at about 2 1 2 hours and then declines slowly to a plateau at 12 hours. Two exponential curves may be constructed from the serum turnover curve: (1) An early phase of tissue distribution and binding with a half-time of 100 minutes and (2) a late dominant curve of metabolism and excretion with a halftime of 38 hours. The dominant turnover time is similar to that observed with intravenous and intramuscular studies, but differences are noted in the early phase. The serum concentration was lower than that found after the intravenous route and greater than after the oral route. After seven days, 50 per cent of the administered dose appeared in the urine and 10 per cent in the stool. Minor local reaction at the injection sites was noted in each patient studied.
Frameworks, cases, and experiments : bridging theory with practice

A theory-oriented approach to teaching and training about negotiation is discussed in this article. Following the flow of a course taught on several continents, I emphasize the value of conceptualizing about the negotiating experience. This is done with concepts, metaphors, frameworks, and research findings summarized in the form of a set of narratives. A series of exercises bring the concepts to life. These include the difference between negotiating values and interests, designing scenarios, and enacting the negotiating functions of analyst, strategist, and designer. Students are also given an opportunity to perform as negotiators and observers in a complex multi-issue negotiation involving security issues similar to those discussed recently between the U.S. and Iraq. They are provided with a research experience that entails coding selected peace agreements for distributive and procedural justice as well as for the durability of those agreements. Lessons learned are generated in de-briefings of the exercises. They are also discussed in a final class where students’ insights, gained from comparative case analyses, are organized by the framework introduced during earlier classes.
On a differential operator containing large complex parameter

Consider a differential operator depending on the parameter . This operator arises in the process of constructing quasi-exponential solutions for the Schrodinger and conductivity equations. Since thesesolutions constitute a widely used and powerful tool for proving uniqueness in inverse problems, properties of the operator P are of interest. We obtain an explicit integral representation for a tempered fundamental solution E of P known in the literature as Faddeev Green function. Given a compactly supported distribution ƒ we investigate asymptotic behavior of the convolution E * ƒ for large |x||ζ|. An explicit asymptotic expansion obtained leads to construction of aparametrix for P which decays rapidly with respect to both |x|and|ζ|. We also consider the Dirichlet problem for the Schrodinger type operator P + q with a compactly supported potential. We obtain sufficient conditions for existence of asymptotic boundary layer type solutions which decay rapidly away from the boundary with respect to |ζ|.
Pulse-spray pharmacomechanical thrombolysis.

The synergistic potential of combining pharmacologic and mechanical methods of thrombolysis has recently been recognized. Pulse-spray pharmacomechanical thrombolysis is one such method, which in our experience has markedly increased the efficiency and acceptability of thrombolysis. With this technique, dialysis grafts usually require only 20–35 min for thrombolysis; bypass grafts or native arteries usually require 60–150 min. The entire procedure is accomplished in one session within the angiography suite, including the supplemental transluminal angioplasty, atherectomy, or stenting that is usually also necessary. Clear understanding of the principle of the method and meticulous attention to technical details is essential for maximal speed, safety, and efficacy.
Basic science of pain.

The origin of the theory that the transmission of pain is through a single channel from the skin to the brain can be traced to the philosopher and scientist Rene Descartes. This simplified scheme of the reflex was the beginning of the development of the modern doctrine of reflexes. Unfortunately, Descartes' reflex theory directed both the study and treatment of pain for more than 330 years. It is still described in physiology and neuroscience textbooks as fact rather than theory. The gate control theory proposed by Melzack and Wall in 1965 rejuvenated the field of pain study and led to further investigation into the phenomena of spinal sensitization and central nervous system plasticity, which are the potential pathophysiologic correlates of chronic pain. The processing of pain takes place in an integrated matrix throughout the neuroaxis and occurs on at least three levels-at peripheral, spinal, and supraspinal sites. Basic strategies of pain control monopolize on this concept of integration by attenuation or blockade of pain through intervention at the periphery, by activation of inhibitory processes that gate pain at the spinal cord and brain, and by interference with the perception of pain. This article discusses each level of pain modulation and reviews the mechanisms of action of opioids and potential new analgesics. A brief description of animal models frames a discussion about recent advances regarding the role of glial cells and central nervous system neuroimmune activation and innate immunity in the etiology of chronic pain states. Future investigation into the discovery and development of novel, nonopioid drug therapy may provide needed options for the millions of patients who suffer from chronic pain syndromes, including syndromes in which the pain originates from peripheral nerve, nerve root, spinal cord, bone, muscle, and disc.
Computational analysis of relative stabilities of polyazine N-oxides

There is considerable interest in polyazine N-oxides as potential frameworks for energetic compounds with relatively high enthalpies of formation and crystal densities. The N+→O− linkages, if appropriately located, may diminish the destabilization associated with nitrogen catenation. We have computationally characterized 40 N-oxides of the isomeric diazines, triazines, and tetrazines in terms of their geometries, relative energies, and (for a representative selection) electrostatic potentials. The presence of N+→O− linkages does partially counteract the destabilizing effects of nitrogen catenation, although the isomers with complete catenation remain the least stable. The stabilizing influence of N+→O− groups, and the accompanying changes in bond lengths, can be understood in terms of resonance charge delocalization to the polyazine rings. The N(O)–N(O) bonds between nitrogens that both bear oxygens tend to be relatively weak. The electrostatic potentials above the polyazine rings become increasingly positive as there are more nitrogens and oxygens; eventually they are positive above all of the carbons and nitrogens and possibly even the oxygens, with negative regions only on the peripheries of the molecules. However, the nitrogens that bear oxygens always have more positive potentials than those that do not.
The effect of in vivo progesterone administration on relaxin-inhibited rat uterine contractions

Progesterone pretreatment in vitro was previously shown to sensitize myometrium to the inhibiting effect of relaxin. The following experiments were performed to control for possible artifacts of the in vitro system and to place these studies on a more physiologic basis. Immature rats were treated with estrogen and either progesterone or vehicle only. Uterine horn segments were isolated and mounted in a muscle bath. After a baseline contraction pattern was established by means of electrical stimulation, porcine relaxin was added to the bath. At all dose levels of relaxin, greater inhibition of contraction amplitude occurred in uterine segments of progesterone-treated animals. Since both progesterone and relaxin are present in the circulation from the time of the missed menses in human pregnancy, this interaction suggests a physiologic synergism in the maintenance of early human pregnancy.
Middle atmosphere slant-path optical turbulence conditions derived from very high-frequency radar observations

Slant path calculations are shown of the transverse coher- ence length (r 0), the isoplanatic angle (u 0), and the Rytov variance (s R ), using a 6-yr data set of refractive index structure parameter (C n ) from 49.25-MHz radar observations at White Sands Missile Range, New Mexico. The calculations are for a spherical wave condition; a wave- length (l) of electromagnetic radiation of 1 mm; four different elevation angles (3, 10, 30, and 60 deg), two path lengths (50 and 150 km); and a platform, such as an aircraft, at 12.5 km MSL (mean sea level). Over 281,000 radar-derived Cn profiles sampled at 3 min intervals with 150-m height resolution are used for the calculations. The approach, an ''onion skin'' model, assumes horizontal stationarity over each entire propaga- tion path and is consistent with Taylor's hypothesis. The results show that refractivity turbulence effects are greatly reduced for the three propagation parameters (r 0 , u 0 , and s R ) as the elevation angle in- creases from 3 to 60 deg. A pronounced seasonal effect is seen on the same parameters, which is consistent with climatological variables and gravity wave activity. Interactions with the enhanced turbulence in the vicinity of the tropopause with the range weighting functions of each propagation parameter is evaluated. Results of a two region model re- lating r 0 , u 0 , and s R to wind speed at 5.6 km MSL are shown. This statistical model can be understood in terms of upward propagating grav- ity waves that are launched by strong winds over complex terrain.
Preliminary quantitative proteomic characterization of glaucomatous rat retinal ganglion cells

Quantitative proteomic analysis was pursued of retinal ganglion cells (RGCs) from rats with unilateral experimental glaucoma. RGCs were isolated from 22 animals by immunopanning after 8 weeks of sustained elevated intraocular pressure. Proteins were quantified by LC MS/MS iTRAQ technology. Of the 268 proteins quantified, ∼8% appeared elevated and ∼13% decreased in glaucomatous RGCs. Voltage-dependent anion channel protein 2, aldose reductase, and ubiquitin were among the significantly elevated proteins while prothymosin was among the significantly decreased. The results demonstrate the feasibility of identifying global proteomic differences in protein expression between purified glaucomatous and control in vivo RGCs.
Effects of Progesterone and Estrogen on Blood Levels of Oxytocin During Vaginal Distention

Normally cycling ewes were treated with intramuscular injections of either progesterone or estradiol dipropionate. Daily injections of progesterone (50 mg in oil) diminished the amount of oxytocin that appeared in jugular vein blood when the vagina was distended with an air-filled balloon. Before treatment, distention increased plasma oxytocin from a prestimulated level of 7 + 1 (mean ±se) to 24 ± 6 μU/ml. After 1 week, the plasma oxytocin level increased from 6 ± 1 to 15 ± 8 μU/ml when the vagina was distended. After 2 weeks of progesterone treatment, no significant increase in plasma oxytocin occurred during the vaginal distention. On the other hand, twice weekly injections of estradiol dipropionate led to marked elevations in the amount of oxytocin appearing in the blood during vaginal distention. From a resting level of 5 ± 1 μU/ml, stimulation increased plasma oxytocin concentration to 87 ± 16 μU/ml in animals treated for 1 week and to 138 ± 53 μU/ml in animals treated for 2 weeks. Several interpreta...
A Mathematical Treatment of Rate Data Obtained in Biological Flow Systems under Nonsteady State Conditions

The problem of determining gas exchange rates from flow system data under nonsteady state conditions is analyzed. A correction factor is presented for obtaining constant rates under nonsteady state conditions. A general formula for obtaining any rate under nonsteady state conditions is also given. Turnover time is defined and discussed in terms of the mathematics presented. The origins of nonsteady states and steady states in flow systems are discussed, as are some of the experimental advantages of working under nonsteady state conditions.
Remote Observing Experiments At Kitt Peak National Observatory

For the past year Kitt Peak National Observatory has been conducting a pilot program of remote observing experiments. Observers who would ordinarily have travelled to Kitt Peak have instead observed from their home institutions. Three voice grade telephone lines are used. One line is used for voice communications with the telescope operator, another line is used to interface with the telescope computer which controls the telescope and instrument, and the third line is used to transmit a slow scan (34 second update time) television picture from the telescope field acquisition camera. Observers have found this system to be quite effective. Problems with telephone line noise have been encountered and several schemes for alleviating these problems are presently being implemented. Plans for more rapid video refresh rates over voice grade lines, the use of greater bandwidth communication links and the multiplexing of voice, data and video over single channel are presently being considered. The goal of the experiments is to investigate the effectiveness of this technique with respect to observing efficiency and cost savings.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Comparative topical absorption and antioxidant effectiveness of two forms of coenzyme q10 after a single dose and after long‐term supplementation in the skin of young and middle‐aged subjects

Coenzyme Q 10 is an endogenous antioxidant found in the skin along with vitamins A, C and E. Coenzyme Q 10 is used increasingly in cosmetic products and is advertised as a skin energizer, protector against skin aging, skin repairer, and an anti-wrinkling agent. As the outermost layer of skin, the stratum corneum is the interface between the body and the environment and requires antioxidants to protect it and the epidermis and dermis below it. Nutrient levels in the stratum corneum correlate with those in the skin. Two forms of coenzyme Q 10 (pure coenzyme Q 10 and a yeast-based coenzyme Q 10 ) were investigated in a commercial vehicle. Two groups of subjects were tested aged 21-29 and 51-70, respectively. Coenzyme Q 10 absorption in the stratum corneum was determined after a 1-hour application and ethanol extraction. Significantly more yeast coenzyme Q 10 was absorbed than the pure coenzyme Q 10 and the middle-aged subjects absorbed about twice as much coenzyme Q 10 as did the younger subjects. Skin antioxidants were significantly increased by yeast coenzyme Q 10 but not by pure coenzyme Q 10 . Peroxides declined in the stratum corneum after twice daily application of coenzyme Q 10 with both forms but the decrease was greater with the yeast form. The older subjects had significantly higher baseline levels of lipid peroxides than did the younger group, indicating an increase in skin oxidative damage with age. The yeast coenzyme Q 10 is the superior form of coenzyme Q 10 for human skin application.
NASA's needs for damage-resistant optics

NASA has plans to monitor the health of Planet Earth using remote sensing techniques from polar orbiting satellites. By using active remote sensors, such as lasers, global, height- resolved, data can be obtained on essential earth variables. Performance specifications and first order designs for current and proposed remote sensing instruments have been developed. Optical damage impacts the performance of these sensors in the attainment of efficiency and reliability.
Isherwood joins Senate staff

Dana J. Isherwood, the 1985–1986 AGU Congressional Science Fellow, has joined the staff of Sen. Albert Gore, Jr. (D-Tenn.), as a legislative assistant on energy issues. After 6 weeks as a Fellow, Isherwood called her role “exciting, demanding, and challenging.” In Gore's office, Isherwood concentrates on nuclear waste issues and groundwater pollution. As legislative assistant, she must present the opposing viewpoints on an issue, she explained. “It's essentially a fact-gathering procedure, to get the information together so that the senator can make up his mind.” Isherwood has met with program managers of nuclear waste projects sponsored by the Department of Energy (DOE) and Nuclear Regulatory Commission (NRC) and with Tennessee state officials.
Complex pleiotropy characterizes the pollen hoarding syndrome in honey bees (Apis mellifera L.)

The pollen hoarding syndrome consists of a large suite of correlated traits in honey bees that may have played an important role in colony organization and consequently the social evolution of honey bees. The syndrome was first discovered in two strains that have been artificially selected for high and low pollen hoarding. These selected strains are used here to further investigate the phenotypic and genetic links between two central aspects of the pollen hoarding syndrome: sucrose responsiveness and pollen hoarding. Sons of hybrid queen offspring of these two strains were tested for sucrose responsiveness and used to produce colonies with either a highly responsive or an unresponsive father. These two colony groups differed significantly in the amount of pollen stored on brood combs and with regard to their relationship between brood and pollen amounts. Additionally, four quantitative trait loci (QTL) for pollen hoarding behavior were assessed for their effect on sucrose responsiveness. Drone offspring of two hybrid queens were phenotyped for responsiveness and genotyped at marker loci for these QTL, identifying some pleiotropic effects of the QTL with significant QTL interactions. Both experiments thus provided corroborating evidence that the distinct traits of the pollen hoarding syndrome are mechanistically and genetically linked and that these links are complex and dependent on background genotype. The study demonstrates genetic worker–drone correlations within the context of the pollen hoarding syndrome and establishes that an indirect selection response connects pollen hoarding and sucrose responsiveness, regardless of which trait is directly selected.
When Counterinsurgency Wins: Sri Lanka’s Defeat of the Tamil Tigers, by Ahmed S. Hashim

For those seeking to understand how the Liberation Tigers of Tamil Eelam (LTTE) – the ‘A-team of terrorist groups’ – was dealt a catastrophic death, Ahmed S. Hashim’s work provides an excellent sta...
Facilitating the development of a global mindset through a cultural experience

The current article describes an assignment utilized in an undergraduate course “Leadership in a Global Society.” The assignment requires students to participate in a cultural experience and interview the leader of the event. Student feedback collected over several semesters indicates that the assignment was invaluable in helping students understand people from cultures different than the ones with which they normally identify. Furthermore, students reported gaining a better understanding of themselves and a willingness to seek out other cultural learning opportunities.
Biological projectiles (phage, yeast, bacteria) for genetic transformation of plants

Bacteriophage lambda particles, yeast cells, and bacterial cells were tested as projectiles to deliver marker/reporter genes into plant cells via the biolistic process. When phage particles were complexed to tungsten or gold particles and used to bombard tobacco cells, fewer than 15 cell clusters per plate transiently expressed β-glucuronidase (GUS). Cells of wildtype Saccharomyces cerevisiae were too large to be effective projectiles, but use of a reduced-size mutant resulted in a small number of transformants. Escherichia coli cells complexed with tungsten were the most effective projectile for plant transformation. Various methods to prepare E. coli were tested to reduce particle size, improve binding of bacteria to metal particles, and/or minimize particle clumping. In maize, the number of transformants was highest when bacteria/tungsten particles were air-dried onto macrocarriers from an aqueous solution. When maize cells were bombarded with bacteria/tungsten projectiles, rates of transient gene expression (2000 per plate) and stable transformation (50 per plate) were only two- to threefold lower than when purified DNA was used. Transformation of tobacco with E. coli projectiles was improved when the bacteria were treated with a series of ethanol and ether washes, then dried into a powder. Nevertheless, tobacco transformation was still 24- (transient) and 200-fold (stable) less than when purified DNA was used. Biological projectiles can be effective for plant transformation and are advantageous because once a DNA construct is made and put into the appropriate microorganism, the need to isolate and purify DNA for the biolistic process is eliminated, which saves time and lessens DNA shear. Such projectiles may be especially well suited where high molecular weight DNA constructs are needed.
Reduced complexity compression algorithms for direct-write maskless lithography systems

Achieving the throughput of one wafer layer per minute with a direct-write maskless lithography system, using 22-nm pixels for 45-nm feature sizes, requires data rates of about 12 Tb/s. In our previous work, we developed a novel lossless compression technique specifically tailored to flattened, rasterized, layout data called context copy combinatorial code (C4), which exceeds the compression efficiency of all other existing techniques including BZIP2, 2D-LZ, and LZ77, especially under a limited decoder buffer size, as required for hardware implementation. In this work, we present two variations of the C4 algorithm. The first variation, block C4, lowers the encoding time of C4 by several orders of magnitude, concurrently with lowering the decoder complexity. The second variation, which involves replacing the hierarchical combinatorial coding part of C4 with Golomb run-length coding, significantly reduces the decoder power and area as compared to block C4. We refer to this algorithm as block Golomb context copy code (block GC3). We present the detailed functional block diagrams of block C4 and block GC3 decoders, along with their hardware performance estimates as the first step of implementing the writer chip for maskless lithography.
Optimized pre-copy calibration of hard drives

In certain contexts a small window of time exists during which law enforcement has access to a hard-drive suspected of containing important information. Given legal authority to copy or seize this disk, a decision must be made whether to use that access time to make a copy of the disk (which may take more than an hour, depending on the size of the disk) and leave its owner unaware that it has been copied. The copying operation uses especially fast drivers that bypass normal error correction mechanisms. Therefore, for the copy to be successful it is necessary that the disk onto which the copy is placed yield exactly the same bits on subsequent reads as would the original disk. To gain confidence that the copy will be successful the copying software typically chooses some sectors at random, copies them, and determines whether their copies are identical to the original. We address the problem of quantifying the conditional probability that the disk will copy correctly given that some samples have copied correctly, as a function of the, number and placement of those samples. Our framework allows us then to choose the placement of those samples in such a way that this conditional probability is maximized.
Self-shunted Nb/AlO/sub x//Nb Josephson junctions

We describe the fabrication and properties of high critical current density (J/sub c/) Nb/AlO/sub x//Nb Josephson junctions with deep-submicron dimensions. The junctions are fabricated using a planarized process in which all levels are patterned using a combination of optical and electron-beam lithography. The base and counter electrodes are defined by reactive ion etching using quartz etch masks to give a minimum feature size of 0.2 microns. For J/sub c/=2.1 mA//spl mu/m/sup 2/ and junction area less than 0.1 /spl mu/m/sup 2/ the devices are self-shunted and exhibit nonhysteretic I-V characteristics. A small hysteresis in the larger junctions is caused by heating in the electrodes.
The daily mean zero‐flux plane during soil‐controlled evaporation: A Green's function approach

A solution is presented of the linearized Richards equation with inclusion of gravity and with appropriate boundary conditions describing the combined soil-controlled surface evaporation and the downward infiltration, following the application of a given amount of precipitation or irrigation. This solution is shown to agree with available field measurements, namely the evolution with time of the zero-flux plane depth and of the rate of soil-controlled evaporation from the bare soil surface. The problem is solved by means of the Green's function method; the result is general enough to be also applicable to flow problems in linear soils with boundary conditions substantially different from the ones considered herein.
Can Britain Defend the Falklands

Thirty years after the 1982 Falklands war, Britain’s capacity to defend the Falkland Islands from Argentina has been repeatedly challenged by former military leaders and analysts. Concern has been ...
Effects of Potassium Oxalate on Dentin Hypersensitivity in Vivo

This study compared 30% dipotassium oxalate (DO) and 3% monohydrogen-monopotassium oxalate (MO) on the reduction of dentin hypersensitivity in vivo. Four treatments were utilized: (1) distilled water followed by 30% DO; (2) distilled water followed by 3% MO; (3) 30% DO followed by 3% MO and (4) distilled water only. Treatments were randomly assigned so that each of the 17 participants received all four treatments, one per tooth tested. Response to cold at baseline and immediately, 1 week, 2 weeks, and 4 weeks posttreatment was measured. Testing began with water at 20 degrees C and decreased at 5 degrees C intervals until a positive response was obtained or until 0 degrees C was reached. No differences were found for time when compared across treatments. When treatments were compared across time, significant reductions occurred in immediate and 4 week posttreatment measurements for treatment 2. In addition, highly significant reductions occurred in 1 week and 2 week posttreatment measurements for treatment 3. Results suggest a decrease in dentin hypersensitivity following the application of 3% MO alone, and 30% DO followed by 3% MO.
A Distributed Reactivity Model for Sorption by Soils and Sediments. 9. General Isotherm Nonlinearity and Applicability of the Dual Reactive Domain Model

Sorption isotherms for a hydrophobic solute probe, phenanthrene, were measured experimentally for 27 different soils and sediments. The linear and Freundlich isotherm models and the Dual Reactive Domain Model (DRDM) were used to fit the resulting data. The results reveal for all soils and sediments studied that (i) the Freundlich model and the DRDM fit the data well, whereas a linear model fails to do so; (ii) values of the organic carbon-normalized distribution coefficient, KOC, calculated from individual isotherm points for a specific sorbent−solute system vary significantly with the aqueous-phase solute concentration, Ce; and (iii) all commonly used correlations of KOC with octanol−water partitioning coefficients and solute solubility limits significantly underestimate KOC for Ce values smaller than approximately one-tenth of aqueous-phase solute solubility, CS. The sorption behaviors of all of the soils and sediments studied are thus inconsistent with the simple concept of linear phase partitioning. T...
Dealing With Short-term Fluctuation in Longitudinal Research

Conclusions. The results revealed that more sensitive assessments of change can be obtained by taking short-term fluctuation into account with measurement-burst designs. In particular, capitalizing on the availability of multiple measures at each occasion to form latent constructs representing the level and change in cognitive performance may provide the most sensitive assessment of cognitive change.
Response to high dietary copper and duration of feeding time on tissue copper concentration of sheep

Two experiments were conducted to study the effect of high dietary Cu and duration of feeding time on tissue mineral composition of sheep to establish a standard curve for future bioassay of supplemental Cu sources. In Experiment 1, 24 crossbred wethers were fed a basal diet (9.24 mg/kg Cu) supplemented with 15, 30 or 45 mg/kg added Cu as cupric acetate for 15 or 30 days. An additional four sheep were killed at day 0 to serve as controls. In Experiment 2, 30 crossbred wethers were injected i.v. with 50 mg ammonium tetrathiomolybdate (ATM) twice weekly for 3 weeks to reduce body Cu stores, then fed the basal diet (7.29 mg/kg Cu) or the basal plus 20, 40, 60 or 80 mg/kg added Cu as cupric acetate for 10 or 20 days. Treatment with ATM reduced liver Cu stores by 52%. In Experiment 1, liver and bone Cu concentrations were greater in sheep supplemented with Cu compared with controls, but there was no difference among sheep fed various added Cu concentrations. In Experiment 2, liver Cu concentration increased linearly in sheep fed 10 days and quadratically in sheep fed 20 days, but serum, spleen and kidney Cu concentrations were not affected by treatment. A bioassay for Cu bioavailability based on liver Cu uptake with a 10-day supplementation period appeared feasable.
Minimally invasive aortic valve surgery: technical considerations and results with the parasternal approach.

Background:The history of surgery over the last 30 years has moved steadily toward minimally invasive surgery; more recent experience with the gall bladder, arthroscopy, and video-assisted thoracic surgery has confirmed this trend. Methods: Our experience in minimally invasive valve surgery between July 1996 and October 1997 included 180 patients, 80 with aortic valve replacement and 100 with mitral valve replacement. The 80 aortic valve replacement patients consisted of 46 males and 34 females, with a mean age of 63 years (range 32 to 90 years) and mean New York Heart Association Functional Class 2.5. The etiology of disease was varied: degenerative in 41 patients, congenital in 17, rheumatic in 8, subacute bacterial endocarditis in 6, myxomatous in 4, and structural valve degeneration in 4. Results: There were two (2.5%) operative deaths, both from multisystem organ failure. Only 16 (20%) of the 80 patients experienced new postoperative atrial fibrillation. The mean length of stay in the hospital was 5 days (range 3 to 24 days). Only 18 (2390) of the 78 surviving patients required posthospital rehabilitation, and there were no late deaths. Morbidity included cerebrovascular accident in 1 patient (1.2%), sternal infection in 1 (1.2%), groin infection in 1 (1.25%), and bleeding requiring reoperation in 1 (1.29%). Conclusions: Minimally invasive cardiac valve surgery is extremely effective and has become our current technique of choice in every mitral and aortic valve patient who does not have coronary artery disease because it reduces the length of hospital stay and cost, requires fewer blood transfusions, and stimulates less atrial fibrillation. (J Card Surg 1998;13:302–305)
Mexico's Tariff Policy

Abstract. While there is common agreement that Mexico's Industrialization period was helped by a protective commercial policy, there has been little testing of this hypothesis. This paper investigates the possibility that Mexico may have used her changing tariff postures not to provide aid for her growing industries but rather to improve either her terms of trade, her revenues or her balance of payments during the 1930–1965 period. The research shows that except for isolated instances none of the individual arguments examined, nor their combination, could explain Mexico's tariff policy. It is therefore concluded that tariffs for protection were employed to achieve industrial development.
Memory Parallelism Using Custom Array Mapping to Heterogeneous Storage Structures

Configurable architectures offer the unique opportunity of customizing the storage allocation to meet specific applications? needs. In this paper we describe a compiler approach to map the arrays of a loop-based computation to internal memories of a configurable architecture with the objective of minimizing the overall execution time. We present an algorithm that considers the data access patterns of the arrays along the critical path of the computation as well as the available storage and memory bandwidth. We demonstrate experimental results of the application of this approach for a set of kernel codes when targeting a Field-Programmable Gate-Array (FPGA). The results reveal that our algorithm outperforms naive and custom data layouts for these kernels by an average of 33% and 15% in terms of execution time, while taking into account the available hardware resources.
Effects of Manipulating Apoptosis on Sindbis Virus Infection of Aedes aegypti Mosquitoes

ABSTRACT Improved control of vector-borne diseases requires an understanding of the molecular factors that determine vector competence. Apoptosis has been shown to play a role in defense against viruses in insects and mammals. Although some observations suggest a correlation between apoptosis and resistance to arboviruses in mosquitoes, there is no direct evidence tying apoptosis to arbovirus vector competence. To determine whether apoptosis can influence arbovirus replication in mosquitoes, we manipulated apoptosis in Aedes aegypti mosquitoes by silencing the expression of genes that either positively or negatively regulate apoptosis. Silencing of the A. aegypti anti-apoptotic gene iap1 ( Aeiap1 ) caused apoptosis in midgut epithelium, alterations in midgut morphology, and 60 to 70% mosquito mortality. Mortality induced by Aeiap1 silencing was rescued by cosilencing the initiator caspase gene Aedronc, indicating that the mortality was due to apoptosis. When mosquitoes which had been injected with Aeiap1 double-stranded RNA (dsRNA) were orally infected with Sindbis virus (SINV), increased midgut infection and virus dissemination to other organs were observed. This increase in virus infection may have been due to the effects of widespread apoptosis on infection barriers or innate immunity. In contrast, silencing the expression of Aedronc, which would be expected to inhibit apoptosis, reduced SINV midgut infection and virus dissemination. Thus, our data suggest that some level of caspase activity and/or apoptosis may be necessary for efficient virus replication and dissemination in mosquitoes. This is the first study to directly test the roles of apoptosis and caspases in determining mosquito vector competence for arboviruses.
Inversion-Recovery of Nitroxide Spin Labels in Solution and Microheterogeneous Environments

Two modifications of a conventional inversion-recovery experiment which exclude the effect of spectral diffusion on the measured spin-lattice relaxation times of rapidly tumbling nitroxide spin labels are described. In the first approach an almost uniform inversion is achieved by means of specially designed pulse trains with excitation patterns which match the three-line nitroxide ESR spectrum. In the second approach we essentially combine an inversion-recovery for the MI ) 0 line with an analog of a pulsed ELDOR technique for MI )( 1 lines in a single experiment. This allows us to reconstruct the recovery of the total magnetization of the ensemble of radicals which is not affected by spectral diffusion. The spin-lattice relaxation times of several nitroxide spin labels in different homogeneous and microheterogeneous environments are measured and compared. The temperature dependence of T1 times is compared for two solvents, methylcyclohexane and carbon disulfide, which differ in nuclear spin concentration by almost a factor of 1000. The reported experimental evidence suggests that interactions with the nuclear spins of a solvent do not significantly contribute to the spin -lattice relaxation of nitroxide spin labels.
The Personal Is Scientific, the Scientific Is Political: The Public Paradigm of the Environmental Breast Cancer Movement

This paper introduces the concept of “boundary movements” to characterize the distinctive growth and strategies of movements involving citizen/science alliances to contend with environmentally related illnesses. This concept is applied to a case study of the environmental breast cancer movement, which has induced changes in treatment options and public perception of breast cancer. Since the early 1990s, a segment of this movement has consistently criticized the traditional paradigms governing research, the epistemology of breast cancer, and popular understandings. Against the traditional focus on genetics, lifestyles, and personal responsibility, this segment's broader messages stress environmental causation and women's participation in science and politics.
Notched and unnotched fatigue behavior of angle-ply graphite/epoxy composites

The axial fatigue behavior of both notched and unnotched graphite/epoxy composites was studied. In unnotched studies, conducted on a 0/+ or - 30 3S AS/3501 laminate, S-N curves were determined for various stress ratios R using simply supported test specimens. Apparent fatigue limits in tension-tension (T-T) and compression-compression (C-C) cycling occurred at about 60% of the respective static strengths. The overall results were expressed in the form of a constant life diagram showing the relationship between mean stress and stress amplitude. The diagram illustrates a skew-symmetry in fatigue life caused by the relatively low compressive strength of the unrestrained test specimens used. In effect, a maximum in fatigue properties occurs at a positive value of mean stress. Results are of significance in situations where structural members are buckling or crippling critical in design.
Analysis of rice Act1 5' region activity in transgenic rice plants.

The 59 region of the rice actin 1 gene (Act1) has been developed as an efficient regulator of foreign gene expression in transgenic rice plants. To determine the pattern and level of rice Act1 59 region activity, transgenic rice plants containing the Act1 59 region fused to a bacterial beta-glucuronidase (Gus) coding sequence were generated. Two independent clonal lines of transgenic rice plants were analyzed in detail. Quantitative analysis showed that tissue from these transgenic rice plants have a level of GUS protein that represents as much as 3% of total soluble protein. We were able to demonstrate that Act1-Gus gene expression is constitutive throughout the sporophytic and gametophytic tissues of these transgenic rice plants. Plants from one transgenic line were analyzed for the segregation of GUS activity in pollen by in situ histochemical staining, and the inheritance and stability of Act1-Gus expression were assayed in subsequently derived progeny plants.
Food Addiction in Humans

Most of the evidence for or against food addiction in humans focuses on similarities between food craving and drug craving. There are numerous parallels in neuroanatomy, neurochemistry, and learning. Indeed, brain mechanisms for craving probably evolved to promote seeking of natural rewards and are taken over by drugs of abuse. Healthy, normal weight individuals, by definition, do not suffer from food addiction; however, overweight and obese individuals could meet clinical criteria. Palatable foods are not responsible for the obesity problem, because even nonpalatable foods can come to be desired and potentially overconsumed. It may be the way in which foods are consumed (e.g. alternating access and restriction) rather than their sensory properties that leads to an addictive eating pattern.