cssi/SciSciGPT-SciSciNet huggingface dataset:
Aqueous phase reactions of mercury with free radicals and chlorine : Implications for atmospheric mercury chemistry

Abstract The role of aqueous phase hydroperoxyl radical (HO2.), hydroxyl radical (.OH) and chlorine (HOCl/OCl−) in the redox cycle of atmospheric mercury is investigated. The contributions of the above species to the aqueous phase Hg(II) concentration under various conditions are evaluated by a chemical kinetic model simulating the chemistry in atmospheric droplets. Based on the model results, .OH is an important daytime oxidant for Hg0 and can account for up to 25 % of the total oxidation rate in the aqueous phase under the model conditions in this study. In the nighttime marine atmosphere, aqueous chlorine can be the most predominant oxidant for Hg0, contributing up to 90 % of the total oxidation rate in the aqueous phase. Increasing pH from 4.0 to 4.3 and decreasing [Cl−] from 1.0 to 0.5 mM increase [Hg(II)] in the droplets by 50 % and 26 %, respectively. Compared to aqueous SO2, HO2. can reduce Hg(II) at a significant rate. In addition, HO2. is the only reductant balancing all the oxidation processes of Hg0 after SO2 is depleted.
A selfadjoint second order hyperbolic system

Abstract We consider a second order hyperbolic system of the type (1) L u = u t t − B u x x = f ( x , t ) , ( x , t ) ∈ T m , where matrix B is a nonsingular constant matrix with positive eigenvalues, ( x , t ) ∈ R 2 and u , f ∈ R n . The set T m is defined to be (2) T m = { ( x , t ) | 0 ⩽ t ⩽ 1 / m , | x | ⩽ 1 − m t } , where m = min { μ k } and μ k 2 is any eigenvalue of the matrix B. We will show that, under the condition u ( x , 0 ) = 0 , | x | ⩽ 1 , a symmetric Green's function G n × n can be constructed [K. Kreith, A selfadjoint problem for the wave equation in higher dimensions, Comput. Math. Appl. 21 (5) (1991) 12–132] so that (3) u ( x , t ) = ∫ ∫ T m G n × n ( x , t ; ξ , τ ) f ( ξ , τ ) d ξ d τ for any function f ∈ L 2 ( T m ) . This will imply that the operator L in (1) over the set L 2 ( T m ) of functions given by Eq. (3) and u ( x , 0 ) = 0 , | x | ⩽ 1 , is selfadjoint. We also note that the same result holds for u in (1) , under the condition that u t ( x , 0 ) = 0 , | x | ⩽ 1 . We further note that when B has only one eigenvalue μ 2 , the function u in Eq. (3) satisfies a boundary condition similar to that of Kalmenov [T. Kalmenov, On the spectrum of a selfadjoint problem for the wave equation, Akad. Nauk. Kazakh SSR Vestnik 1 (1983) 63–66] on the characteristic boundaries of T μ .
Father-Absence and Boys' School Performance in Barbados

In a study in rural Barbados that controls for race, social class, and cultural attitudes toward birth status, test and school data do not support the "classic" prediction of a direct, negative relationship between father-absence and boys' school performance. In this community, paternal absence during the first two years of life seems modestly beneficial to the boys' later performance, as does paternal presence during the third through fifth years. An interpretation of these findings is offered that contrasts the alternative predictions of the perspectives of economic determinism, stigma-trauma, sex-role identification, and interaction within the household. The interactionist interpretation, supplemented by ethnographic data on the community, best explains the empirical findings.
Surface characterization of the stannous fluoride-enamel interaction

Abstract Infrared internal reflection spectroscopy (IRS) has been employed to characterize the nature of faceted human enamel surfaces subsequent to in-vitro topical treatment with filtered, 10 per cent SnF 2 solution. IRS spectra of treated slabs were compared with reference tin-phosphates and similarly treated samples of enamel powder. It was found that the spectral features of enamel shifted with SnF 2 treatment such that infrared absorption peaks corresponded closely to those of pure Sn 3 F 3 PO 4 . Some interpretations of the experimental data are discussed relative to possible clinical implications.
Atomic beam magnetic resonance

Abstract The techniques of atomic beam research are reviewed with particular emphasis on most recent applications to low abundance isotopes and their nuclear properties. The well known space-quantization connection between the Zeeman and Paschen-Back conditions is rediscussed to show the effect on the observed transitions caused by anomalous hyperfine level ordering. In the second part the applications of the method to Am, Cm, Pu and Pa are discussed with respect to the elucidation of the ground state electronic wave functions. Current results are presented. The role of the hyperfine anomaly is discussed and the various atomic beam methods of measuring the nuclear magnetic moment directly are compared.
The Effects of Time-Out from Positive Reinforcement on the Operant Behavior of Preschool Children.

Abstract Sixty preschool children participated in two experiments testing the suppressive effects of time-out from positive reinforcement (TO). In Experiment I a lever press was reinforced on a VI schedule with a 10-second TO administered after every seventh response (FR7). When the punished response was the only one available, TO depressed response rate by approximately 25%. However, this suppression was of relatively brief duration. With the introduction of an unpunished alternative, TO produced complete and lasting suppression. In Experiment II a response preference was established by reinforcing responses on one lever more frequently than those on another and then punishing responses on the preferred lever with a 10-second TO. Results showed that under punishment by TO the formerly unpreferred lever was chosen even though the frequency of reinforcement for the two levers was identical.
On two-level optimization

Decentralized planning has long been recognized as an important decision making problem. Many approaches based on the concepts of large scale system decomposition have generally lacked the ability to model the type of truly independent subsystems which have often existed in practice. Similarly, tractable game-theoretic approaches have not allowed for a continuous solution space in which one player's decision restricts the feasible choices of another. This correspondence offers a formulation to help model this type of decision making hierarchy. Characterizations and algorithmic approaches for a class of two-level problems are discussed.
Phase Stability of Cubic Pyrochlore Rare Earth Tantalate Pinning Additives in YBa2Cu3O7−δ Superconductor

Phase stability of cubic-pyrochlore-structured RE3TaO7 (RTO, where RE = rare earth elements) pinning additives in YBa2Cu3O7- (YBCO) superconductor and the pinning properties influenced by RTO addition into YBCO films were investigated. RTO completely reacts with YBCO and is converted to cubic-double-perovskite-structured Ba2RETaO6 (BRETO), a more thermodynamically stable tantalate phase within YBCO. In RTO-doped YBCO films, BRETO self-assembled nanocolumnns align along the c-axis of the film and play a major role in the improvement of flux pinning and Jc performance over wide magnetic field and angular ranges.
Quark mass renormalization of staggered fermions

Abstract The QCD light quark mass renormalized at a 1 GeV scale in the MS scheme is obtained from the numerical results of the lattice QCD simulation with staggered fermions. The primary emphasis is given to the connection between the lattice and continuum parameters. These results are compared with those from a QCD sum rule.
G1 Compartmentalization and Cell Fate Coordination

Pauklin and Vallier show that, whereas early G1 is permissive for TGF-β-dependent endoderm differentiation, cyclin D restricts the activity of Smad2/3 in late G1, resulting in a switch from endoderm to neuroectoderm potential in pluripotent stem cells. These findings provide insight into how signaling, the cell cycle, and lineage specification are coordinated.
Survival of Escherichia coli O157:H7 in soil and on carrots and onions grown in fields treated with contaminated manure composts or irrigation water

Abstract Many foodborne outbreaks of enterohemorrhagic Escherichia coli O157:H7 infection have been associated with the consumption of contaminated vegetables. On-farm contaminations through contaminated manure or irrigation water application were considered likely sources of the pathogen for several outbreaks. Field studies were done to determine the survival of E. coli O157:H7 on two subterranean crops (carrots and onions), and in soil fertilized with contaminated manure compost or irrigated with contaminated water. Three different types of composts, PM-5 (poultry manure compost), 338 (dairy manure compost) and NVIRO-4 (alkaline stabilized dairy manure compost), and irrigation water were inoculated with an avirulent strain of E. coli O157:H7 at 107 cfu g−1 and 105 cfu ml−1, respectively. A split-plot block design plan was used for each crop, with five treatments (one without compost, three with each of the three composts, and one without compost but with contaminated irrigation water applied) and five replicates for a total of 25 plots, each measuring 1.8×4.6 m2, for each crop. Composts were applied to soil as a strip at a rate of 4.5 metric tons ha−1 before carrots and onions were sown. Contaminated irrigation water was sprayed once on the vegetables at the rate of 2 l per plot for this treatment 3 weeks after carrots and onions were sown. E. coli O157:H7 survived in soil samples for 154–196 days, and was detected for 74 and 168 days on onions and carrots, respectively. E. coli O157:H7 survival was greatest in soil amended with poultry compost and least in soil containing alkaline-stabilized dairy manure compost. Survival profiles of E. coli O157:H7 on vegetables and soil samples, contaminated either by application of contaminated compost or irrigation water, were similar. Hence, preharvest contamination of carrots and onions with E. coli O157:H7 for several months can occur through both contaminated manure compost and irrigation water.
Crack bridging by uncracked ligaments during fatigue-crack growth in SiC-reinforced aluminum-alloy composites

Micro-mechanisms of crack-tip shielding associated with the growth of fatigue cracks in metalmatrix composites are examined with specific emphasis on the role of crack bridging by uncracked ligaments. Simple analytical models are developed for such bridging induced by both overlapping cracks and by coplanar ligaments in the wake of the crack tip; the models are based on respective notions of a critical tensile strain or critical crack-opening displacement in the ligament. The predicted degree of shielding derived from these mechanisms is not large, but is found to be consistent with experimental observations in high-strength P/M aluminum alloys reinforced with 15 to 20 vol pct of SiC particulate.
Distribution and Variability of Surface Soil Properties at a Regional Scale

Information on the probability distribution and variability of soil properties at a regional scale could improve the ability of the USDA-Natural Resources Conservation Service (NRCS) to monitor soil condition using the National Resources Inventory (NRI). Our objective was to evaluate the hypothesis that the probability distribution of 17 physical, chemical, and biological soil properties are: (i) normally distributed, or (ii) log-normally distributed at a regional scale, and to estimate the magnitude of change that may be detected assuming either a normal or log-normal distribution. Samples were collected irrespective of soil series from two Major Land Resource Areas (MLRAs) (no. 9 and 105), and from the Ascalon (fine-loamy, mixed, superactive, mesic Aridic Argiustoll) and Amarillo (fine-loamy, mixed, superactive, thermie Aridic Paleustalf) soils in MLRA 67 and 77, using the NRI sampling design. Most soil properties were non-normally distributed, with the frequency of non-normality varying between MLRAs. Confining sampling to a single soil series did not consistently improve the precision with which soil properties were estimated. Log e transformation resulted in normal distributions for most soil properties and reduced variability two- to threefold. However, a few soil properties remained non-normally distributed. Soil pH may be monitored at the regional scale with a high degree of precision. Small changes in soil C content (3-8% of the regional mean) may be detected using log, transformed total organic C as the indicator. Sampling soil properties as part of the NRI should improve NRCS' ability to monitor soil condition on a regional scale.
Effect of Neutron- and Gamma-Radiation on Glass Optical Waveguides

Multimode glass optical waveguides with very low attenuation have been made by laboratory techniques. A desirable property of optical waveguides is the resistance to the environmental hazard of nuclear (neutron and gamma) radiation. Experiments were performed on the change in attenuation of the optical waveguides with cumulative 14 MeV neutron irradiation and with /sup 60/Co gamms irradiation. The results of these experiments are presented. (AlP)
Detritus utilization by Mytilus edulis

Feeding expriments showed that salt marsh vascular plant detritus is a poor food for Mytilus edulis . In laboratory experiment tissue weight of mussels increased slightly when Spartina foliosa and Salicornia virginica detritus was added to background seawater rich in organic matter. However, mussels lost weight when detritus was added to background seawater with a lower organic matter content. Aged and unaged plant material were equally poor in food value for M. edulis . Mussels in the Tijuana Estuary grew substantially during the period of the laboratory experiments.
Set theory with a filter quantifier

The incompleteness of ZF set theory leads one to look for natural extensions of ZF in which one can prove statements independent of ZF which appear to be “true”. One approach has been to add large cardinal axioms. Or, one can investigate second-order expansions like Kelley-Morse class theory, KM. In this paper we look at a set theory ZF(aa), with an added quantifier aa which ranges over ordinals. The “aa” stands for “almost all”, and although we will consider interpretations in terms of the closed unbounded filter on a regular cardinal κ, we will consider other interpretations also. We start in §1 by giving the axioms for the theory ZF(aa) and presenting a completeness theorem which gives a model-theoretic definition of ZF(aa). In §2 we investigate set theory with a satisfaction predicate and interpret it in a fragment of ZF(aa). In §3 we generalize the methods of §2 to obtain a hierarchy of satisfaction predicates. We use these predicates to prove reflection theorems, as well as to prove the consistency of certain fragments of ZF(aa). Next, in §4 we discuss expandability of models of ZF to models of fragments of ZF(aa) and of Kelley-Morse. We conclude in §5 with a discussion of an extension ZF(aa) + DET of ZF(aa) in which the quantifier aa is self-dual.
A general formula for the sensitivity of population growth rate to changes in life history parameters.

This paper considers the sensitivity of population growth to small changes in birth, growth, survival, and migration probabilities for an arbitrary population classification (i.e., age, instar, size, developmental stage, age, and spatial location, etc.). The stage-specific life history parameters are expressed in a discrete-time system of linear difference equations, the dominant eigenvalue of which defines the population growth rate. The sensitivity of this eigenvalue to production of class i by class j individuals is shown to be proportional to the product of the reproductive value of stage i and the abundance of stage j in the stable stage distribution. This formula is readily computable, and several examples are presented. For the special case of age-structured populations, this formula reduces to those derived by Hamilton, Emlen, and Goodman.
The effect of chronic administration of tryptophan to rats on liver tryptophan pyrrolase activity.

Abstract The relation of rat liver tryptophan pyrrolase activity to the number of daily injections of tryptophan has been examined. The level of this enzyme increased in response to a test injection of tryptophan throughout a 50-day period of chronic administration of tryptophan, although the magnitude of the response varied, being greater each day for the first 17 days, then decreasing to slightly less than that to a single injection by the 50th day. The same magnitude of responses of this enzyme to a single test tryptophan injection was obtained in rats injected daily with saline during the same period. However, in the reverse situation, the injection of a single dose of saline to rats chronically injected with tryptophan did not produce any greater response of pyrrolase activity than that after a single saline injection. When the activities of both apoenzyme and completely activated enzyme in the livers of rats injected with tryptophan for 19 days were compared with a similar group of rats receiving only one tryptophan injection, it was seen that the levels of both apoenzyme and activated enzyme were higher in the livers of the chronically injected rats.
Determination Of Inherent Contrast Resolution In X-Ray Imaging Using Electron Density And Effective Atomic Number Differences

The problem of determining the inherent contrast resolution of an x-ray imaging device (CT or projection x-ray) has not thus far been satisfactorily solved. The contrast signal-to-noise ratio depends on the geometry and composition of the object being imaged, the x-ray beam spectrum and the detector spectral efficiency (signal) as well as a host of factors which contribute to the quantum and non-quantum statistical fluctuation in the image (noise). Because contrast depends on machine spectral factors as well as phantom atomic number differences, measurements made using any single low contrast phantom cannot yield the inherent contrast resolution but only the contrast resolution of the system for phantoms of that geometry and composition. We have overcome this problem by developing and using two phantoms to measure inherent contrast resolution: in one phantom the contrast-generating structures differ from the background material only in electron density, while in the second phantom the contrast is generated purely by a difference in effective atomic number of the materials. Measurements made using these phantoms allow the determination of the inherent contrast resolution of the device for objects of any composition. In this paper, descriptions of the construction and composition of the electron density and atomic number phantoms are given. Computer simulations and preliminary measurements of the inherent contrast resolution of clinical x-ray imaging systems are presented. From these, one can develop optimum methods of operating x-ray imaging devices.
Continuous flow intersections: A safety and environmental perspective

Continuous flow intersections (CFIs) were invented to improve traffic operations of conventional intersections that suffer severe congestion caused by heavy left-turn movements by eliminating the protected left-turn phase and thus increasing the intersection capacity and reducing the number of conflict points. However, since drivers in the USA are not familiar with the operations of CFIs, there is a need to evaluate CFIs in terms of driver behavior, safety, and operational efficiency. In addition, there is a need to quantify the environmental impacts associated with CFI operations. The research presented in this paper assesses the operation of CFIs by conducting before and after field and simulation evaluations. The study concludes that drivers are initially unfamiliar with the operational characteristics of CFIs. These problems are found to be temporary and are resolved once drivers become acquainted with the operation of CFIs. The simulation analysis demonstrates how the introduction of a CFI results in operational improvements, fuel savings, and vehicle emissions reductions at different total traffic demand levels and for varying left turn volumes. The study demonstrates that CFIs are more robust to fluctuations in overall intersection demand levels and the left turning volumes compared to conventional signalized intersection control.
Recurrent Selection for Extended Plant Height and Herbage Yield in Cicer Milkvetch

Cicer milkvetch (Astragalus cicer L.) produces about 50% of its total herbage in the first harvest and only about 12% in the third harvest under a three-harvest regime. The photoperiod-induced-dormancy response offers an opportunity to improve herbage yield during the third growth period (1 August-10 September). Therefore, the objective of this study was to improve herbage yield during the third growth period without sacrificing yield in the other two growth periods. This study was conducted with spaced-plants under irrigation near Fort Collins, CO, from 1984 through 1990. Extended plant height (length of longest stem) relative to the cultivar Monarch was increased 105, 108, and 114% in the first, second, and third harvests, respectively, by two cycles of recurrent selection. Mean plant herbage yield relative to Monarch was increased 113, 107, 116, and 111% for the first, second, and third harvests and for total yield, respectively, by two cycles of recurrent selection. Although herbage yield was increased substantially in the third harvest, simultaneus increases in the first and second harvests resulted in no difference for seasonal distribution of total yield. The 15 clones with the best performing polycross progenies for extended plant height and herbage yield were used as parents for the cultivar Windsor. Recurrent selection for lack of the photoperiod-induced-dormancy trait was an effective procedure for unproving extended plant height and herbage yield of cicer milkvetch during the third growth period of a three-harvest system
Loopless generation of k -ary tree sequences

Abstract Roelants van Baronaigien (1991) gave an algorithm to generate all n -node binary tree representations with constant time between them. He used the well-known rotation operation on nodes for balancing binary search trees and represented binary trees by binary tree sequences. This paper generalizes the rotation to k -ary trees and uses it to generate k -ary tree representations with constant time between them.
Recent results of fracture experiments on carbon steel welded pipes

Abstract Several pipe fracture experiments were conducted with circumferential cracks in the center of ferritic nuclear pipe welds. These experiments involved either submerged arc or shielded metal arc welds with either through-wall cracks or internal surface cracks. The pipe diameters varied from 940 mm (37 inches) to 152 mm (6 inches), and thickness from 10·9 mm (0·43 inches) to 86·6 mm (3·41 inches). Some of the through-wall and surface-cracked pipe experiments were conducted under constant internal pressure and four-point bending. The test temperature was 288°C (550°F). The results of these experiments are compared with limit-load analyses, the ASME, Section XI, article IWB-3650 criterion, and more elaborate elastic-plastic fracture mechanical analysis.
Computational studies of adsorption in metal organic frameworks and interaction of nanoparticles in condensed phases

In this review, we describe recent efforts to systematically study nano-structured metal organic frameworks (MOFs), also known as metal organic heat carriers, with particular emphasis on their appl...
Psychometric properties of the Wolpe-Lazarus assertiveness scale

Abstract The psychometric properties of the Wolpe-Lazarus Assertiveness Scale (WLAS) were evaluated with a sample of 100 male and 157 female psychiatric patients. There were no significant differences with regard to males and females for total WLAS scores. The WLAS seems to be internally consistent and has acceptable split-half and test-retest reliabilities. A factor analysis performed separately for males and females indicates that the 10 most prominent factors account for about 60% of the accumulated variance. The primary factor, shared by males and females, was labeled General Expressiveness . There was little evidence for the external validity of the WLAS when total scores were correlated with performance on a role play test. However, when WLAS factor scores were evaluated in light of role played performance, somewhat better evidence of the external validity of the WLAS was found in two of the factors for the females.
Genetics and Epigenetics of Eating Disorders

Eating disorders (EDs) are serious psychiatric conditions influenced by biological, psychological, and sociocultural factors. A better understanding of the genetics of these complex traits and the development of more sophisticated molecular biology tools have advanced our understanding of the etiology of EDs. The aim of this review is to critically evaluate the literature on the genetic research conducted on three major EDs: anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED). We will first review the diagnostic criteria, clinical features, prevalence, and prognosis of AN, BN, and BED, followed by a review of family, twin, and adoption studies. We then review the history of genetic studies of EDs covering linkage analysis, candidate gene association studies, genome-wide association studies, and the study of rare variants in EDs. Our review also incorporates a translational perspective by covering animal models of ED-related phenotypes. Finally, we review the nascent field of epigenetics of EDs and a look forward to future directions for ED genetic research.
Analysis of decision boundaries in linearly combined neural classifiers

Combining or integrating the outputs of several pattern classifiers has led to improved performance in a multitude of applications. This paper provides an analytical framework to quantify the improvements in classification results due to combining. We show that combining networks linearly in output space reduces the variance of the actual decision region boundaries around the optimum boundary. This result is valid under the assumption that the a posteriori probability distributions for each class are locally monotonic around the Bayes optimum boundary. In the absence of classifier bias, the error is shown to be proportional to the boundary variance, resulting in a simple expression for error rate improvements. In the presence of bias, the error reduction, expressed in terms of a bias reduction factor, is shown to be less than or equal to the reduction obtained in the absence of bias. The analysis presented here facilitates the understanding of the relationships among error rates, classifier boundary distributions and combining in output space.
Effect of heta-starch colloidal solutions on reticuloendothelial phagocytic system (RES) function in burned and infected rats.

Abstract The biodistribution of the plasma expander colloidal solution, heta-starch (HES), has been examined in rats, subjected to thermal injury or sepsis. The ability of these solutions to alter RES phagocytic function of [ 99m Tc]-sulphur colloid ([ 99m tc]SC) uptake in vivo has been examined. The biodistribution of radiolabelled HES has been determined in normal rats. The HES colloidal solution has no deleterious effect upon RES function in vivo in the thermally injured animals or the septic animals as compared to sham controls. In addition, the HES colloidal solution seemed to be distributed primarily within the liver, spleen and kidney, with a small amount residing in the lung. Thermal injury did not increase the uptake of this material by the lung. These results suggest that the use of HES in thermally injured and septic individuals has no deleterious effects on RES function, nor does it accumulate in the lungs, and, hence, should be advocated for use in these situations.
358 EFFECT OF GENTAMICIN ON NEUROMUSCULAR FUNCTION (NMF) OF A HYPERMAGNESEMIC NEONATE

Treatment of maternal pre-eclampsia with MgSO4 is reported to produce flaccidity, lethargy and hyporeflexia in their infants. Aminoglycosides can also affect NMF. Both agents interfere with release of acetylcholine, producing a defect in neuromuscular transmission. A term infant was born to a pre-eclamptic mother treated with 28 gm MgSO4. The baby had cord blood Mg++ of 3.9 mg/d1 and demonstrated neuromuscular compromise as measured by ulnar nerve stimulation studies and neurologic examination. Improvement occurred as serum Mg++ level approached normal (1.5 ± 0.2 mg/d1). At 48 hrs. of age, septicemia was suspected and antibiotics (ampicillin 50 mg/kg IV q 12 hrs. and gentamicin 2.5 mg/kg IV q 12 hrs.) begun. Two hours after receiving the second dose of gentamicin, the infant had respiratory, followed by cardiac arrest. Resuscitation was successful and 24 hrs. later NMF was studied before and after a gentamicin dose. Increasing fatigability of NMF occurred at 1 and 2 hrs. after gentamicin. This case suggests that depressed NMF in a hypermagnesemic infant may be further compromised by aminoglycoside therapy.
Predicting CMOS Inverter Response in Nuclear and Space Environments

Linear system theory techniques were used to predict threshold-voltage shifts for 4007 inverters at dose rates of 270, 49.7, and 0.19 rad(Si)/s, from a transient annealing curve determined following a 5-rad(Si)/s 60Co irradiation. These predictions were compared with threshold-voltage shifts obtained following 60Co irradiations actually performed at these dose rates, and the agreement is excellent. We observed a wide range of annealing rates for commercial and military 4007 inverters--some Al-gate inverters exhibited very little annealing following irradiation, while an Si-gate inverter completely annealed back to its preirradiation threshold voltage in ~5 × 105 s. The radiation responses of 4007's from a specific manufacturer with different packaging (i.e., plastic or ceramic) and/or electrical characterization (i.e., high-reliability or JAN) were found to vary significantly. Maintaining bias following irradiation was determined to be important in characterizing the anneal of both Al-and Si-gate inverters. Finally, dose-enhancement effects on the threshold-voltage shift were observed for 60Co inpool irradiations where the source and sample were separated by 20 in. of water.
The effect of voids on the sliding friction of polyimide film

Abstract Voids 1.5–2 μm in diameter have been found randomly distributed just under one surface of commercial polyimide film. Their presence leads to a significant reduction in friction and wear. The data do not suggest the source of the reduced friction.
On the Tuning of Predictive Controllers: Inverse Optimality and the Minimum Variance Covariance Constrained Control Problem

This paper presents a systematic tuning approach for linear model predictive controllers based on the computationally attractive minimum variance covariance constrained control (MVC3) problem. Unfortunately, the linear feedback policy generated by the MVC3 problem is incompatible with the algorithmic framework of predictive control, in which the primary tuning vehicle is the selection of objective function weights. The main result of this paper is to show that all linear feedbacks generated by the MVC3 problem exhibit the property of inverse optimality with respect to an appropriately defined linear quadratic regulator (LQR) problem. Thus, the proposed tuning scheme is a two-step procedure: application of the MVC3 problem to achieve tuning objectives, followed by application of inverse optimality to determine the predictive control weights from the MVC3-generated linear feedback.
The chemokine system and CCR5 antagonists: potential in HIV treatment and other novel therapies.

SUMMARY Since the recognition of human acquired immune deficiency syndrome, numerous classes of pharmacologic therapeutics have been developed to manage the disease. Current therapy includes co-administration of combinations of drugs classified by their mechanism of action as ‘transcriptase inhibitors’, ‘protease inhibitors’, ‘integrase inhibitors’ and the more recent ‘fusion inhibitors’. This review focuses on the chemokine system and the recognition of chemokine receptors as targets for anti-human immunodeficiency virus (HIV) therapy. The FDA-approved chemokine (C‐C motif) receptor 5 (CCR5) antagonist maraviroc (Selzentry )i s discussed in detail, along with another compound vicriviroc, currently in clinical trials. The mechanism of action, pharmacokinetics, toxicity and current status of research on CCR5 antagonists is described. Further, potential therapeutic uses of these agents other than anti-HIV therapy are discussed.
Efficient and Responsive Stochastic Optimization

Abstract This paper is devoted to the problem of behavior design, which generalizes the standard global optimization problem of finding an optimizer by producing, on the search space, a probability density function referred to as the behavior. The generalization depends on a parameter, the level of selectivity, such that as this parameter tends to infinity, the behavior becomes a delta function at the location of the global optimizer. The motivation for this generalization is that traditional off-line global optimization is unresponsive to perturbations of the objective function. A novel approach to inexpensive responsiveness is to utilize the theory of Selective Evolutionary Generation Systems (SEGS), which sequentially and probabilistically selects a candidate optimizer based on the ratio of the fitness values of two candidates and the level of selectivity. Using time-homogeneous, irreducible, ergodic Markov chains to model a sequence of local, and hence inexpensive, dynamic transitions, this paper shows that such transitions result in “rational” behavior, and the efficient and responsive search for an optimizer.
Pharmacodynamic and toxicokinetic evaluation of the novel MEK inhibitor, PD0325901, in the rat following oral and intravenous administration

The MEK–mitogen-activated protein kinase (MAPK) signal transduction pathway is involved with numerous cellular processes including cell growth and differentiation. Phosphorylation of MAPK (pMAPK) by MEK results in activation of this pathway. In various solid tumors, the MEK–MAPK pathway is constitutively active; therefore inhibition of this pathway may provide a therapeutic strategy for treating cancer. The objective of this study was to determine the extent and duration of inhibition of pMAPK in selected normal tissues in rats following single oral or intravenous (IV) doses of the novel MEK inhibitor, PD0325901. Male Sprague–Dawley rats (9/group) received either single oral (PO) or IV doses of PD0325901 at 10, 30, or 100 mg/kg (60, 180, and 600 mg/m2, respectively). Controls received vehicle alone which was aqueous 0.5% hydroxypropylmethyl-cellulose/0.2% Tween 80 for PO dosing and 20% beta-cyclodextran sulfobutyl ether in water (w:v) for IV dosing. Animals (3/group/day) were euthanized on Days 2, 3, and 4, at approximately 24, 48, and 72 h after dosing, respectively. The effects on pMAPK in liver and lung were determined by Western blot analysis and compared with plasma PD0325901 levels. Satellite animals (6/dose/route) received single PO or IV doses and serial blood samples were collected for determination of toxicokinetic parameters of PD0325901 and its major metabolite. In general, systemic exposure to PD0325901 was comparable between routes of administration due to high PO bioavailability (56–109%). Plasma area under the concentration–time curve values of the pharmacologically inactive carboxylic acid metabolite ranged from 18 to 40% of PD0325901. Clinical signs of toxicity occurred at 100 mg/kg PO or IV, indicating the maximum-tolerated dose had been achieved. On Day 2, pMAPK was inhibited 57–95% in liver and 86–99% in lung at all doses, irrespective of route of administration. On Day 3, lung pMAPK remained inhibited 75–91% at all IV doses and by 88% after the 100-mg/kg PO dose. Liver pMAPK remained inhibited 79 and 91% on Day 3 after 100 mg/kg by IV and PO doses, respectively. On Day 4, liver pMAPK was still inhibited 66% after the 100-mg/kg PO dose. The EC50 and EC90 plasma drug levels for inhibition of lung pMAPK were calculated to be 20 and 99 ng/ml, respectively. Liver pMAPK levels were inhibited at least 50% at plasma PD0325901 concentrations ≥50 ng/ml. In conclusion, single PO or IV doses of PD0325901 resulted in dose-dependent inhibition of pMAPK in liver and lung. Inhibition of pMAPK in liver was comparable between routes of administration at ≤30 mg/kg, whereas inhibition of pMAPK in lung occurred for a longer duration following IV administration. Measurement of pMAPK in normal tissues served as a means for assessing the pharmacologic activity of PD0325901 and should be included in toxicity studies to evaluate toxicity–pharmacology relationships.
The high temperature hollow cathode ion source

Abstract A description is given of a novel ion source for an electro-magnetic isotope separator, which makes use of the hollow cathode effect. The new ion source has a very small plasma volume and a very high temperature. Over-all efficiencies as high as 40% for argon and 60% for xenon have been measured.
An application of optimal control theory to equation solving

A rapidly convergent search technique for finding the root of a scalar equation is proposed. At each step the method requires the construction of the envelope of a certain class of functions. Constructing this envelope is equivalent to solving an optimal control problem with state space constraints. The major portion of the paper deals with this control problem.
Impaction from rectangular jets

Abstract The efficiency with which particles are collected by impaction on a plate at a distance S from a rectangular jet of width W and length L has been studied as a function of the particle Stokes number P at several values of S W between 0.35 and 5.0. The value of P for which the efficiency was 0.5 varied with solS W in the manner predieted by theory, but was consistently higher than predicted. The length of the jet throat affected collection efficiency and significant end effects were observed, despite the large value of L W (= 16).
Using Citation Analysis to Assess Scholarly Productivity

In recent years, interest in rating the quality of schools of education has increased. When budgets are tight, administrators must make choices that affect many faculty and students, sometimes with the help of only fragmentary information. Although program review can be a complex process involving numerous issues such as scholarly productivity, professional and community service, instruction, and funding, questions of scholarly accomplishment are often pivotal. Research and publication are the driving forces in the modern university, and evaluators of schools of education must be attuned to this fact.
A Critical Approach to Critical Thinking in TESOL

This article presents four more-or-less independent reasons why TESOL educators should be cautious about adopting critical thinking pedagogies in their classrooms: (a) Critical thinking may be more on the order of a non-overt social practice than a well-defined and teachable pedagogical set of behaviors; (b) critical thinking can be and has been criticized for its exclusive and reductive character; (c) teaching thinking to nonnative speakers may be fraught with cultural problems; and, (d) once having been taught, thinking skills do not appear to transfer effectively beyond their narrow contexts of instruction. A more recently developed model of cognitive instruction, cognitive apprenticeship, is then briefly discussed as a possible alternative to more traditional thinking skills pedagogies. This thing we call “critical thinking” or “analysis” has strong cultural components. It is more than just a set of writing and thinking techniques—it is a voice, a stance, a relationship with texts and family members, friends, teachers, the media, even the history of one's country. This is why “critical analysis” is so hard for faculty members to talk about; because it is learned intuitively it is easy to recognize, like a face or a personality, but it is not so easily defined and is not at all simple to explain to someone who has been brought up differently. (Fox, 1994, p. 125)
Structured Maintenance Policies on Interior Sample Paths

We examine the problem of adaptively scheduling perfect observations and preventive replacements for a multi-state, Markovian deterioration system with silent failures such that total expected discounted cost is minimized. We model this problem as a partially observed Markov decision process and show that the structural properties of the optimal policy hold for certain non-extreme sample paths. © 2007 Wiley Periodicals, Inc. Naval Research Logistics 54: 645-655, 2007 Consider a production system that degrades over time due to usage and age. Because the operating and replacement costs for such systems tend to increase in the deteriora- tion level, properly timed preventive maintenance actions can reduce total cost. Furthermore, a priori statements about the structure of such preventive maintenance policies can both accelerate their computation and ease their implementation. In this spirit, we establish structural properties of the opti- mal policy that minimizes the total expected discounted cost over the infinite horizon for a system that undergoes discrete- time, finite-state Markovian deterioration with three actions available in each decision epoch: replace, produce without inspection (i.e., "no action"), and produce with a costly, per- fect inspection. As a result of the replace action, the system returns to an "as good as new" state. The other two actions do not alter the deterioration state; however, the inspections reveal the current deterioration state with certainty. Other authors who consider this problem (6-9) differ in their choice of state definition, but establish the same struc- tural properties of the optimal policy along ordered subsets of their respective state spaces. We extend these results by intro- ducing a new state definition and establishing the same struc- tural properties for ordered subsets of states not previously considered.
Inequality and the Territorial Fragmentation of Solidarity

A long tradition of research has shown decentralized political structures as an important cause behind lower levels of redistribution and higher levels of inequality. This article offers an alternative interpretation of the association between fragmented fiscal structures and higher levels of inequality. I argue that the distributive effects of decentralization depend on the preexisting territorial patterns of inequality. Therefore, the political choice between alternative fiscal structures is largely driven by their expected distributive consequences. As a result, the territorial structure of inequality becomes an important factor to explain why some fiscal structures are more integrated than others. Two mechanisms link regional income distributions and preferences about the decentralization of redistributive policy: differences in the demand for redistribution associated with interregional income differences, and differences in the demand for social insurance associated with the incidence of labor market risks. I test the argument using a data set of fourteen countries in the Organization for Economic Cooperation and Development (OECD) over the period 1980–2000. In addition, I illustrate the potential of the approach by analyzing why social solidarity remains territorially fragmented in the European Union despite the fact that it has a common currency and a common market.Previous versions of this article were presented in seminars at Cornell University, Syracuse University, Duke University, and the 2005 APSA meetings. I benefited from comments in all these events. In addition, I thank Christopher Anderson, Tony Atkinson, Neal Beck, Carles Boix, Matt Cleary, Thomas R. Cusack, Alberto Diaz-Cayeros, Gosta Esping-Andersen, Kai Konrad, Mitchell Orenstein, Jonas Pontusson, Adam Przeworski, Jonathan Rodden, David Rueda, David Soskice, Ernesto Stein, Duane Swank, Daniel Treisman, Brian Taylor, Michael Wallerstein, and Erik Wibbels for their very helpful comments on earlier versions. Krishna Ayyangar provided excellent research assistance. Finally, I want to thank Lisa Martin and two anonymous reviewers for their very helpful suggestions. Financial support from the Juan March Institute, Nuffield College (Oxford), the Wissenschaftszentrum Berlin and the Center for Policy Research (Syracuse University) is gratefully acknowledged. The usual disclaimer applies.
Relative Navigation of Air Vehicles

This paper derives the full equations of motion for relative navigation of air vehicles. An extended Kalman filter is used for estimating the relative position and attitude of two air vehicles designated leader and follower. All leader states are assumed known, whereas the relative states are estimated using line-of-sight measurements between the vehicles along with acceleration and angular rate measurements of the follower. Noise is present on all measurements, whereas biases are present only on the latter two. The global attitude is parameterized using a quaternion, whereas the local attitude error is given by a three-dimensional attitude representation. An application of the new theoretical developments is also given, which involves determining an optimal trajectory to improve the estimation accuracy of the system. A cost function is derived based upon the relative position elements of the estimator covariance. State constraints are appended to the cost function using an exponential term. Results show that minimization of this cost function yields a trajectory that improves accuracy of both the position and attitude state estimates.
Mechanically tunable photonic crystal

Many technologies have been developed to actively change the band gap of a photonic crystal. While reasonable tuning speeds have been achieved, large simultaneous changes in band gap have not. This is suitable for optical switching and routing, however, a much larger tuning range is required for optical switching of multiple wavelength signals. In this paper, we show the design and analysis of a MEMS device which allows for higher tuning capabilities by leveraging the high strain achievable within a polydimethylsiloxane (PDMS) polymer attached to silicon comb drives. This novel design can lead to photonic crystals with more tunability than other state-or-the-art designs while maintaining acceptable speeds over 1 kHz.
Spanning subgraphs of a hypercube II: Double starlike trees

A double star is a tree with exactly two nodes which are not endnodes. A double starlike tree T is a subdivision of a double star S in which the edge joining the two central nodes of S is not subdivided. We characterize the double starlike trees with maximum degree three that span a hypercube.
Molecular Dynamics Characterization of the Response of Ni/Al Nanolaminates Under Dynamic Loading

We use a recently developed molecular dynamics method with an accurate, first-principles-based force field to study shock propagation in Ni/Al nanolaminates and the induced (highly exothermic) chemical reactions. We characterize both perfect nanolaminates and specimens containing small (4-nm diameter) voids. The new method enables the accurate description of both the nonequilibrium shock-loading process and the long time evolution of the shocked material, providing an atomic-level picture of the complex interplay between the mechanical, thermal, and chemical processes that govern the behavior of the metastable composites. We shock the nanolaminates in the direction normal to the Ni/Al interfaces, leading to multiple wave reflections, due to the elastic mismatch between Ni and Al; this leads to the Al layers having a higher temperature during the early stages of the process. In the perfect nanolaminates, the chemical reactions start at the interfaces closest to the impact plane and then propagate through the material. A rapid increase in the rate of chemical reactions (3Ni + Al → Ni 3 Al) is observed following the melting of the Ni and Al layers. We estimate the propagation velocity of the chemical front to be about 200 m/s. The porous samples exhibit much faster energy-release rates, due to the mechanical intermixing of Al and Ni caused by shock-induced pore collapse and the higher shock temperatures.