cssi/SciSciGPT-SciSciNet huggingface dataset:
Gaussian weighting of ocular wave-front measurements

The measurement of ocular wave-front error gives insight into the optical performance of the eye and possibly a means for assessing visual performance. The visual system responds not only to the quality of the optical image formed on the retina but also to the processing that occurs in the retina and the brain. To develop a metric of visual performance based on wave-front error measurements, these latter processes must somehow be incorporated. In representing the wave-front error in terms of Zernike polynomials, it appears that terms with lower angular frequency have a greater deleterious effect on visual performance than higher-angular-frequency terms. A technique for weighting the pupil function of the eye with a Gaussian filter is demonstrated. It is further demonstrated that the variance of the Gaussian-weighted wave-front error is well correlated with visual performance.
Cyclic fluctuations of water levels in Lake Ontario

Abstract Water levels along the southeastern shoreline of Lake Ontario have been recorded continuously for more than 110 yr. Interpretation of the Lake Ontario hydrograph reveals marked seasonal and long-term, water-level fluctuations. Fourier transforms permit decomposition of time functions into component frequencies that can be analyzed to determine periodicity within the data. Both long- and short-term periodicities can be isolated and described in terms of amplitude and phase. The most prominent period is the seasonally controlled 1-yr cycle; however, low-frequency cycles of 8, 11, 22 and 36 yr also exist. High-water levels occur if peaks of several periodicities coincide, and extreme levels occur if all peaks are in phase. Future water levels can be predicted from position and amplitude of component frequencies.
The K-shell Auger decay of atomic oxygen

Relative photoionization cross sections for and produced by the Auger decay of a 1s hole in atomic oxygen were measured by using synchrotron radiation between 525 and 553 eV. Energies and quantum defects of the members of the two Rydberg series converging to and ionization thresholds were determined. In addition, the and ionization thresholds were calculated from the two Rydberg series. The 182 meV resolution of the monochromator allowed a detailed study over both thresholds revealing evidence for post-collision interaction and allowing a comparison of the ionization continuum above both and thresholds with that of the ionization continuum above the Ar edges. This comparison indicates that the lifetimes of the Ar(2p) and O(1s) hole states are approximately the same.
Pressure Sensitive Nonassociative Plasticity Model for DRA Composites

Discontinuously reinforced aluminum (DRA) is currently used where design considerations include specific stiffness, tailorable coefficient of thermal expansion, or wear resistance. Plastic deformation plays a role in failures due to low cycle fatigue or simple ductile overload. DRA is known to exhibit pressure dependent yielding. Plastic deformation in metals is widely regarded to be incompressible, or very nearly so. A continuum plasticity model is developed that includes a Drucker–Prager pressure dependent yield function, plastic incompressibility via a nonassociative Prandtl–Reuss flow rule, and a generalized Armstrong–Frederick kinematic hardening law. The model is implemented using a return mapping algorithm with backward Euler integration for stability and the Newton method to determine the plastic multiplier. Material parameters are characterized from uniaxial tension and uniaxial compression experimental results. Model predictions are compared to experimental results for a nonproportional compression–shear load path. The tangent stiffness tensor is nonsymmetric because the flow rule is not associated with the yield function, which means that the commonly used algorithms that require symmetric matrices cannot be used with this material model. Model correlations with tension and compression loadings are excellent. Model predictions of shear and nonproportional compression–shear loadings are reasonably good. The nonassociative flow rule could not be validated by comparison of the plastic strain rate direction with the yield function and the flow potential due to scatter in the experimental results. The model is capable of predicting the material response obtained in the experiments, but additional validation is necessary for the condition of high hydrostatic pressure.
Performance-based functional assessment: an algorithm for measuring physical capabilities

The description of users with motor limitations is a significant dilemma for accessibility researchers and system designers alike. Current practice is to use descriptors such as medical diagnoses to represent a person's physical capabilities. This solution is not adequate due to similarities in functional capabilities between diagnoses as well as differences in capabilities within a diagnosis. An alternative is user self-reporting or observation by another person. These solutions are also problematic because they rely on individual interpretation of capabilities. The current research focuses on defining an objective, quantitative and repeatable methodology for assessing a person's physical capabilities in relation to use of computer technology. Results from this initial study are encouraging, including the development of a model which accounts for up to 85% of the variance in user capabilities.
Rapid detection of bacterial proliferation in food samples using microchannel impedance measurements at multiple frequencies

We present a novel method for detecting viable bacteria in suspensions such as milk and apple juice. Underlying the technique is the fact that bacteria in aqueous suspensions can store a large amount of charge, and thus act like (non-ideal) capacitors. Thus increased numbers of bacteria due to proliferation increases the capacitance of the bulk of the suspension. However, this increase cannot be directly measured since the capacitance of the solid–liquid interface (“double layer”) in effect “screens” the latter. We present a method (derived from an earlier one) that is able to discern such changes with high sensitivity and robustness. We also demonstrate its ability to monitor food quality/safety by detecting bacterial proliferation in “real world” liquid food samples like milk and apple juice. We are able to detect ~ 1, 10, 100, and 1000 CFU/mL of E. coli in milk in about 4.5, 3, 2, and 0.5 h, respectively. For the same initial loads, the corresponding times to detection (TTDs) for Lactobacillus in apple juice are approximately 8, 6, 4, and 1 h. These represent a greater than 4-fold reduction in TTD when compared to automated systems on the market such as RABIT, Bactometer etc. We can achieve such low TTDs for low initial loads since, due to the much greater effective charge holding capacity of bacterial cells (compared to surrounding media), we are able to detect a change in the overall bulk capacitance of the suspension as the bacterial numbers cross a threshold of around 500 CFU/mL.
Computers: Projecting VLSI's impact on microprocessors: Single-chip microcomputers with 1 million bits of information, English-language programming, and canned software are seen ahead

The paper gives a general discussion about the silicon chip industry, of both its present situation and its possible situation in the future. The possible impact of the microprocessor is discussed in great detail and the author comes to the conclusion that the large scale use of this unit will greatly enhance the electronics industry in terms of speed, packing and efficiency and so ultimately decrease costs.
Properties of heterozygous diploids between strains ofPenicillium chrysogenum selected for high penicillin yield

Three strains ofPenicillium chrysogenum selected for high penicillin yield and of independent lineage were marked with suitable genetical characters prior to the synthesis of several heterozygous diploids. These parental strains had domestic codes, C, D and Y. Two diploids, between differently labelled mutants of strain C and Y, produced similar amounts of penicillin to strain C, which was less than that produced by strain Y. Previous work had indicated that genes responsible for increased penicillin yield were recessive and the present results suggested that such genes in strains C and Y were allelic, apart from the presence of one or more additional recessive mutations leading to greater penicillin production in the higher yielding parent. Three diploids made between mutants of strains D and Y were lower in penicillin yield than either original parent and only in the case of one diploid compared with one of the parental strains was this difference not significant. In strains D and Y, therefore, there may have been some recessive genes concerned with increasing penicillin yield which were non-allelic. However, no first order segregants arising spontaneously or subsequent to X-ray treatment produced higher levels of penicillin than the better yielding original parent in any cross.
A stop-restart solid propellant study with salt quench

Experiments were conducted to gain insight into the unsatisfactory performance of the salt quench system of solid propellants in earlier studies. Nine open-air salt spray tests were conducted and high-speed cinematographic coverage was obtained of the events. It is shown that the salt spray by the detonator is generally a two-step process yielding two different fractions. The first fraction consists of finely powdered salt and moves practically unidirectionally at a high velocity (thousand of feet per second) while the second fraction consists of coarse particles and moves randomly at a low velocity (a few feet per second). Further investigation is required to verify the speculation that a lower quench charge ratio (weight of salt/propellant burning area) than previously employed may lead to an efficient quench
Bladder and External Urethral Sphincter Function After Prenatal Closure of Myelomeningocele

Purpose: We compared urodynamic findings in patients who underwent prenatal closure of myelomeningocele with those of patients who underwent postnatal closure, and equivalent lower urinary tract evaluations.Materials and Methods: Urodynamic studies of 5 patients (2 boys, 3 girls) who underwent prenatal closure of myelomeningocele were compared to those of 88 patients with similar level lesions who underwent repair postnatally between 1979 and 2002.Results: All 5 patients in the prenatally treated cohort had lower lumbosacral lesions on neurological examination. These patients displayed no evidence of electromyographic activity, indicating complete denervation of the external sphincter. In comparison 34 of the 88 patients in the postnatal cohort (39%) lacked sphincter activity at newborn examination, with similar findings noted at 1-year evaluation. In terms of bladder function all 5 patients in the prenatal cohort exhibited detrusor overactivity, compared to 33 of the 88 patients (38%) in the postnatal co...
Use of the 82Sr/82Rb generator in clinical PET studies

The use of the 82Sr/82Rb generator in clinical positron emission tomography (PET) studies of myocardial perfusion has been described. An infusion pump is used to deliver the short-lived 82Rb from the generator to the patient. Various characteristics of the generator and the infusion system are described. The 82Rb yield was 69.8 +/- 13.3% and the 82Sr breakthrough was always less than the limit of 0.02 microCi/mCi 82Rb. The yield of 82Rb increased with the flow rate and the potency of the generator. Patients with coronary artery disease were studied for myocardial perfusion abnormalities by the 82Rb PET technique and images of excellent diagnostic quality were obtained.
Evolutionary framework for test of autonomous systems

A DoD mission and challenge is to enable a high percentage of autonomous vehicles in the warfighter fleet by 2015. These systems will need to display a high degree of autonomous capabilities. The capabilities of these autonomous systems must be acceptable to the warfighter and his/her logistical support structure. Autonomous systems of the future will need to be tested so their mission capabilities and robustness are predictable to the warfighter. The principal challenge therefore is the set of test strategies for these future autonomous systems. The goal of the test community is that these autonomous systems be broadly accepted to seamlessly operate either independently or as part of a human-in-the-loop system. Our goal is to develop an efficient intelligent test process that will enable the rapid introduction of autonomous systems on the battlefield. We propose a novel war game simulation-based multi-objective evolutionary test framework that combines the elements of testing an autonomous system's mission execution capabilities as a function of its innate capabilities and evolutionary computation.
Neither ore, nor coal, nor markets: A policy-oriented view of steel sites in the USA

Markusen A. (1986) Neither ore, nor coal nor markets: a policy-oriented view of steel sites in the USA, Reg. Studies 20, 449–462. Locational work on steel stresses the growing role of consuming markets over resources in shaping the evolution of mill sites. Here it is argued that four additional factors have governed steel siting in the USA: agglomeration economies, oligopolistic behaviour, the role of the state, and conflict between capital and labour. The relative strength of each factor varies by era and region. As a result, the economic development prospects for places like Pittsburgh and Chicago are quite different.
Using High-Throughput Screening Data To Discriminate Compounds with Single-Target Effects from Those with Side Effects

The most desirable compound leads from high-throughput assays are those with novel biological activities resulting from their action on a single biological target. Valuable resources can be wasted on compound leads with significant 'side effects' on additional biological targets; therefore, technical refinements to identify compounds that primarily have effects resulting from a single target are needed. This study explores the use of multiple assays of a chemical library and a statistic based on entropy to identify lead compound classes that have patterns of assay activity resulting primarily from small molecule action on a single target. This statistic, called the coincidence score, discriminates with 88% accuracy compound classes known to act primarily on a single target from compound classes with significant side effects on nonhomologous targets. Furthermore, a significant number of the compound classes predicted to have primarily single-target effects contain known bioactive compounds. We also show that a compound's known biological target or mechanism of action can often be suggested by its pattern of activities in multiple assays.
Darwin: a ground truth agnostic CAPTCHA generator using evolutionary algorithm

We designed and implemented Darwin, the first CAPTCHA generator using evolutionary algorithm. We evaluated the effectiveness of our proposed CAPTCHAs with MTurk users (non-attackers) and Antigate workers (attackers). Due to our ground-truth agnostic fitness function, we are able to discover a new category of CAPTCHAs in which attackers answer correctly but non-attackers answer incorrectly.
A study of a multistage column for fine coal beneficiation

A novel multistage column has been successfully developed for fine coal beneficiation. This new column uses vortex-inducing contactors as stages to enhance the separation process. This paper presents an experimental study of the beneficiation characteristics or such a multistage column in terms of recovery rate, heating value recovery and impurity rejection. The paper also discusses the effects of dosage on the column performance. The results are compared with those obtained from the conventional column (without vortex-inducing contactors).
Effects of irradiation on nucleic acid formation.

SummaryMice of the A strain bearing bilateral transplants of mammary carcinoma were used to demonstrate an indirect effect of irradiation on the desoxypentose nucleic acid turnover rate. In 2 experiments the animals were irradiated by means of radioyttrium colloids which localize in the liver when injected intravenously and remain at the site of injection when given intramuscularly. The nucleic acid turnover rate was measured by giving a tracer dose of radioactive sodium phosphate, sacrificing the animals after 2 hours, and isolating the desoxypentose nucleic acid from their tumors and livers. The specific activity of the nucleic acid phosphorus was measured and considered to be an index of the turnover rate. It was found necessary to purify the nucleic acid much more carefully than is done in standard methods in order to obtain a constant specific activity upon successive reprecipitations.The animals whose livers were irradiated with 4.25 × 105 ergs showed only 66% of the tumor nucleic acid specific acti...
Efficient social contracts and group selection

We consider the Stag Hunt in terms of Maynard Smith’s famous Haystack model. In the Stag Hunt, contrary to the Prisoner’s Dilemma, there is a cooperative equilibrium besides the equilibrium where every player defects. This implies that in the Haystack model, where a population is partitioned into groups, groups playing the cooperative equilibrium tend to grow faster than those at the non-cooperative equilibrium. We determine under what conditions this leads to the takeover of the population by cooperators. Moreover, we compare our results to the case of an unstructured population and to the case of the Prisoner’s Dilemma. Finally, we point to some implications our findings have for three distinct ideas: Ken Binmore’s group selection argument in favor of the evolution of efficient social contracts, Sewall Wright’s Shifting Balance theory, and the equilibrium selection problem of game theory.
Differential response of cysteine residues in pig muscle phosphoglucose isomerase to seven sulfhydryl-modifying reagents.

Abstract The three cysteine residues per subunit of pig muscle phosphoglucose isomerase show different reactivities toward various sulfhydryl reagents. The organomercurial, p -mercuribenzoate, can titrate two of the sulfhydryl groups under nondenaturing conditions. 2,2′-Dithiodipyridine, 5,5′-dithiobis(2-nitrobenzoic acid), iodoacetamide, methyl 2-pyridyl disulfide, and 2-(2′-pyridylmercapto)mercuri-4-nitrophenol all label only one sulfhydryl group under the same conditions, whereas iodoacetic acid does not react with any of the sulfhydryl groups except when the enzyme is fully denatured. It is concluded, therefore, that charge, rather than steric restraint, is the determining factor for the differences seen in the modification patterns of the enzyme by these reagents. When enzyme was first labeled with 2,2′-dithiodipyridine and subsequently with p -mercuribenzoate, it was found that the latter, in a secondary process, will stoichiometrically react with the anion released by the former after the initial reaction with cysteine. The differences in reactivity of the cysteine residues toward the referred-to reagents have been exploited to specifically modify each of the three individual cysteine residues of pig muscle phosphoglucose isomerase.
Corticosterone, novelty-induced hyperglycemia, and chlordiazepoxide

Abstract Rats moved to novel environments for a 20 minute period showed increased plasma corticosterone levels—the greater the difference between the housing context and the novel environment, the greater the increase in corticosterone. Plasma glucose levels (PGL) also increased with increasing environmental novelty and these PGL changes were moderated by pretreatment with chlordiazepoxide (10 mg/kg). The increases in corticosterone and PGL were greater in a context previously shown to lead to hyperglycemic conditioning following insulin administration than in a context previously shown to lead to hypoglycemic conditioning. These results imply that the directionality of glycemic conditioning may be related to the initial stressfulness of the conditioning environment.
Parametric Experimental Study of Viscosity of Nanofluids

There is a lot of interest in the research community about nanofluids due to their high thermal conductivity and potential applications as heat transfer fluids, however a systematic investigation on the viscosity of the nanofluids is still lacking from the literature. Any heat transfer enhancement due to force convention, also leads to increase in the pressure drop. Knowledge of the pressure drop is very important to understand the pumping requirements. Pressure drop is directly proportional to the viscosity of the liquid. Addition of nanoparticles will enhance the viscosity of the nanofluids. In this paper experimental results on the viscosity of propylene glycol based nanofluids are reported for various parameters such as nanoparticle size, temperature and volume fraction. Effect of Brownian motion on the viscosity of nanofluids is also explored.© 2006 ASME
A chiral molecular square with metallo-corners for enantioselective sensing.

A family of chiral molecular squares based on fac-Re(CO)3Cl metallocorners and enantiopure atropisomeric bipyridine bridging ligands (L1-4) have been synthesized in high yields by refluxing ClRe(CO...
Equivoluminal, lamé-type waves in composite hollow cylinders☆

Abstract A description is given of axially symmetric, equivoluminal waves propagating along the axis of a composite cylinder made up of concentric hollow cylinders. The waves can be viewed as a superposition of SV-type waves reflected at the free boundaries, and involve motion in planes through the cylinder axis. Waves of this type can exist only if the shear wave velocity is the same in the various media of the composite cylinder and, in addition, the thicknesses of the different media are proportional to the zeros of a simple transcendental equation.
China's provincial diplomacy to Africa: applications to health cooperation

There is a prevailing view of China as a unitary actor in its relationships with African countries. This view is incomplete: on the contrary, China is a collection of provinces, autonomous regions and municipalities with myriad strategic ties to African countries, with decentralization shaping the current form of Chinese government and its level of efficiency. In this paper, factors have been explored for why Chinese provinces have played a role in foreign cooperation in health of African countries, in addition to trade and foreign direct investment. Incentives and disincentives for Chinese provinces to engage internationally in foreign cooperation and health assistance have been identified. The concept of paradiplomacy for health has been presented and this typology has been applied to the example of Chinese medical teams. Finally, we draw linkages between China and other members of Brazil, Russia, India, China, and South Africa.
Water softening using polyelectrolyte-enhanced ultrafiltration

Abstract The use of polyelectrolyte-enhanced ultrafiltration (PEUF) for water softening has been studied at several temperatures in the presence and absence of added salt. It is shown that in the absence of added salt. PEUF is highly effective in the rejection of up to 99.7% of hardness ions from an aqueous stream. At a low concentration of added salt. PEUF is effective in the removal of hardness. As salt concentration increases, however, hardness rejection decreases dramatically. The experimental results have been effectively modeled using an ion-binding model based on Oosawa's two-phase approximation theory.
Mechanism of Inhibition of Site-specific Recombination by the Holliday Junction-trapping Peptide WKHYNY: Insights into Phage λ Integrase-mediated Strand Exchange

Abstract Holliday junctions are central intermediates in site-specific recombination reactions mediated by tyrosine recombinases. Because these intermediates are extremely transient, only artificially assembled Holliday junctions have been available for study. We have recently identified hexapeptides that cause the accumulation of natural Holliday junctions of bacteriophage λ Integrase (Int)-mediated reactions. We now show that one of these peptides acts after the first DNA cleavage event to stabilize protein-bound junctions and to prevent their resolution. The peptide acts before the step affected by site affinity ( saf ) mutations in the core region, in agreement with a model that the peptide stabilizes the products of strand exchange (i.e. Holliday junctions) while saf mutations reduce ligation of exchanged strands. Strand exchange events leading to Holliday junctions in phage λ integration and excision are asymmetric, presumably because interactions between Int and some of its core-binding sites determine the order of strand cleavage. We have compared the structure of Holliday junctions in one unidirectional and in two bidirectional Int-mediated pathways and show that the strand cleavage steps are much more symmetric in the bidirectional pathways. Thus Int–DNA interactions which determine the order of top and bottom strand cleavage and exchange are unique in each recombination pathway.
Intestinal Epithelial Serum Amyloid A Modulates Bacterial Growth In Vitro and Pro-Inflammatory Responses in Mouse Experimental Colitis

Background Serum Amyloid A (SAA) is a major acute phase protein of unknown function. SAA is mostly expressed in the liver, but also in other tissues including the intestinal epithelium. SAA reportedly has anti-bacterial effects, and because inflammatory bowel diseases (IBD) result from a breakdown in homeostatic interactions between intestinal epithelia and bacteria, we hypothesized that SAA is protective during experimental colitis.
Diffraction isosbestic points and longer-range ordering in the SixSe1−x glass system

Abstract The systematics of structural trends in the SixSe1−x 0.0⩽x≲0.40 glass system have been summarized for r ⩽ 9 A . Changes in structure for 0.0⩽x≲0.23 are characterized by a linear dependence upon x. This linear dependence leads to the novel observation of Diffraction Isosbestic Points. Abrupt changes in the nature of the structure of these glasses occur at x ∼ 0.23 and x = 0.33. The structures of glasses in the composition range 0.0⩽x≲.23 may be understood in terms of a clustered unit model. Changes in both nearest neighbor and molecular ordering underlie the dramatic structural rearrangements which occur about the x = 0.33 composition.
Cell partitioning in two-polymer aqueous phase systems and cell electrophoresis in aqueous polymer solutions. Red blood cells from different species.

Abstract A correlation, with some exceptions, between the partitioning behavior of red blood cells (RBCs) from different species in charge-sensitive dextran-poly(ethylene glycol) (PEG) aqueous phase systems and their relative electrophoretic mobilities (EPMs) in phosphate-buffered saline (PBS) has previously been reported. This relationship has now been further probed by carrying out RBC electrophoresis in media ( i.e. , dextran-rich bottom or PEG-rich top phases) more closely approximating the environment in which RBC partitioning takes place to see whether a better correlation would ensue. The ratios of viscosity-corrected EPMs of different species' RBCs in (diluted) dextran-rich or PEG-rich phases/EPMs of the respective species' RBCs in PBS differ for a number of species, and from each other, reflecting thereby differences in kind ( i.e. , dextran or PEG) and nature of polymer interaction with these RBCs. There is a general tendency for EPMs in any of the tested media to correlate with both the cells' relative partition ratios as well as with their relative EPMs in one of the other media. However, examination of the behavior of different species' RBCs taken two species at a time indicates that their relative EPMs in any two suspending media or in one suspending medium and partitioning often differ. Thus, both the cell partition ratio and the cell EPMs obtained in polymer media must, at least in some cases, reflect surface properties other than or in addition to the charge reflected by EPM measurements in PBS or saline. Cell electrophoresis in polymer solutions thereby provides an additional parameter for discriminating between surface properties of certain closely related cell populations.
Type-I GaSb based single lateral mode diode ridge lasers operating at room temperature in 3.1-3.2 μm spectral region

Broad area type-I GaSb based diode lasers have recently exceeded 100 mW continuous wave room temperature powers in 3.1-3.2 μm spectral region. Certain applications such as single frequency sources for spectroscopy and efficient coupling to single mode fiber require single lateral mode laser operation. We characterize and compare two types of lasers with similar structures and various ridge widths emitting at 3.1 and 3.2 μm. We obtain 35 and 25 mW of continuous wave single lateral mode power from 8 and 13 μm wide ridge lasers emitting at 3.1 and 3.2 μm respectively. This constitutes a threefold improvement compared to the previous result. Both devices had ridges etched to the depth leaving approximately 300 nm of the top p-cladding in the areas outside the ridges. For 3.2 μm emitting lasers the dielectric thickness was 220 nm while it was 510 nm for 3.1 μm emitting lasers. Gain spectra were measured by Hakki- Paoli technique for various ridge widths. From gain spectra we extract differential gain and internal loss. We find that the internal loss in thin dielectric, 3.2 μm emitting laser is about 14 cm-1 while it is 7 cm-1 in thick dielectric, 3.1 μm emitting laser for the ridge widths of 13 and 8 μm exhibiting single lateral mode operation respectively. Internal losses measured on broad area, 100 μm wide lasers processed from the same materials are similar and around 6-7 cm-1. We discuss reasons for the internal loss increase with the aid of simulation of optical mode field and loss in our waveguide structures.
Influencing local computer technology policy via a K-12/University Collaboration

Abstract This article discusses a district-wide study conducted in collaboration with local officials and researchers from a nearby university. The goals of the study were collaboratively derived by university and representatives of K-12 education (i.e. from kindergarten to completing compulsory education) and included: (1) determining how teachers in the district were using computers in instruction, (2) determining factors that influenced these uses and (3) developing a local policy agenda from the results of the study. Survey methodology was implemented using Dillman's (1978) Total Design Method and a 92% response rate was obtained. The study suggests that teachers are primarily using computers for drill and practice or as rewards for completing work, that teachers lack confidence in meeting many of the state technology standards and that teachers are not satisfied with the support they receive. The study also suggests that systemic teacher preparation efforts focused on developing teachers' instruction...
Effort and contrafreeloading

Three groups of rats were trained to barpress for food pellets on the left side of an operant chamber and subsequently were offered a choice between this familiar food source and a novel food source on the right side for 10 consecutive daily sessions. One group was offered a choice between barpressing for “earned” pellets from the familiar source or obtaining identical “free” pellets from the novel source. A second group was offered a choice between two earned food sources, and a third group was offered a choice between two free food sources. The results were in agreement with a neophobia-optimality model. The latter groups, which were given a choice between two equally effortful food sources, overwhelmingly preferred the familiar source. The former group, which was given a choice between the familiar earned food source and a novel free food source, preferred the novel source.
Homoleptic 2,2'-bipyridine metalates(-I) of iron and cobalt, one cocrystallized with an anthracene radical anion and the other with neutral anthracene.

Homoleptic 2,2′-bi­pyridine (bipy) metalates of iron and cobalt have been synthesized directly from the corresponding homo­leptic anthracene metalates. In the iron structure, bis­[([2.2.2]cryptand)potassium(I)] tris­(2,2′-bi­pyridine)­fer­rate(–I) anthracene(–I), [K(C18H36N2O6)]2[Fe(C10H8N2)3](C14H10), the asymmetric unit contains one potassium complex cation in a general position, the Fe center and one and a half bipy ligands of the ferrate complex on a crystallographic twofold axis that includes the Fe atom, and one half of an anthracene radical anion whose other half is generated by a crystallographic inversion center. The cations and anions are well separated and the geometry about the Fe center is essentially octa­hedral. In the cobalt structure, ([2.2.2]cryptand)potassium(I) bis­(2,2′-bi­pyridine)­cobaltate(–I) anthracene hemisolvate tetra­hydro­furan (THF) disolvate, [K(C18H36N2O6)][Co(C10H8N2)2]·0.5C14H10·2C4H8O, the asymmetric unit contains the cation, anion, and both cocrystallized THF solvent mol­ecules in general positions, and one half of a cocrystallized anthracene mol­ecule whose other half is generated by a crystallographic inversion center. The cation and anion are well separated and the ligand planes in the cobaltate anion are periplanar. Each anthracene mol­ecule is midway between and is oriented perpendicular to a pair of symmetry-related bipy ligands such that aromatic donor–acceptor inter­actions may play a role in the packing arrangement. The lengths of the bonds that connect the bipy rings support the assertion that the ligands are bipy radical anions in the iron structure. However, in the case of cobalt, these lengths are between the known ranges for a bipy radical anion and a bipy dianion, and therefore no conclusion can be made from the crystallography alone. One cocrystallized THF solvent mol­ecule in the cobalt structure was modeled as disordered over three positions with appropriate geometric and thermal restraints, which resulted in a refined component mass ratio of 0.412 (4):0.387 (3):0.201 (3).
Efficient modeling of impulsive ELF antipodal propagation about the Earth sphere using an optimized two-dimensional geodesic FDTD grid

The letter reports the initial application of a geodesic finite-difference time-domain (FDTD) grid to model impulsive extremely low frequency electromagnetic wave propagation about the Earth sphere. The two-dimensional transverse-magnetic grid is comprised entirely of hexagonal cells, except for a small fixed number of pentagonal cells needed for grid completion. Grid-cell areas and locations are optimized to yield a smoothly varying area difference between adjacent cells, thereby maximizing numerical convergence. The new FDTD grid model is considerably superior to our previously reported latitude-longitude grid because it is simpler to construct, avoids geometrical singularities at the poles, executes about 14 times faster, provides much more isotropic wave propagation, and permits an easier interchange of data with state-of-the-art Earth-simulation codes used by the geophysics community. We verify our new model by conducting numerical studies of impulsive antipodal propagation and the Schumann resonance.
Reconfigurable DNA origami to generate quasifractal patterns.

The specificity of Watson–Crick base pairing, unique mechanical properties of DNA, and intrinsic stability of DNA double helices makes DNA an ideal material for the construction of dynamic nanodevices. Rationally designed strand displacement reactions can be used to produce dynamic reconfiguration of DNA nanostructures postassembly. Here we describe a ‘fold–release–fold’ strategy of multiple strand displacement and hybridization reactions to reconfigure a simple DNA origami structure into a complex, quasifractal pattern, demonstrating a complex transformation of DNA nanoarchitectures.
SLS: An Advanced Symbolic Layout System for Bipolar and FET Design

This paper describes features of the Symbolic Layout System (SLS), an advanced layout system for VLSI designs. Symbolic layout is a method by which point objects, wires, and regions are sketched on a virtual grid, converted to shapes, and then spaced according to a set of minimum ground rules using a compactor. Point objects are defined as terminals, FET transistors, contacts, or vias. These objects are connected using wires or "sticks." Flexible regions (orthogonal polygons) are provided for building wells, bipolar transistors, or complex devices. Network extraction is performed on the wires and point objects to check connectivity and provide net information to the compactor. The compaction process is interactively controlled, allowing the user to override design rules, insert jogs, build compaction fences, and specify the compaction center. SLS is technology independent, making it useful for bipolar and FET technologies.
Energetics of domain formation in thermomagnetic recording

A new model for the distribution of perpendicular magnetization in thin magnetic films supporting a circular domain is proposed. The contributions of various sources to the magnetic energy are determined and the demagnetizing effect in particular is discussed at length. It is shown that a demagnetizing energy density per unit area of the domain wall can be defined which, unlike the domain wall energy density arising from exchange and anisotropy contributions, is a function of film thickness h. For domains of large radius and small wall thickness (compared with h), the demagnetizing energy density is found to be linearly increasing with h. A typical cycle of thermomagnetic recording on a thin ferrimagnetic film with room temperature compensation point is then studied, and the effect of various parameters on the formation process and stability of reverse magnetized domains is discussed.
Inhibitors for the hepatitis C virus RNA polymerase explored by SAR with advanced machine learning methods.

Abstract Hepatitis C virus (HCV) is a global health challenge, affecting approximately 200 million people worldwide. In this study we developed SAR models with advanced machine learning classifiers Random Forest and k Nearest Neighbor Simulated Annealing for 679 small molecules with measured inhibition activity for NS5B genotype 1b. The activity was expressed as a binary value (active/inactive), where actives were considered molecules with IC50 ⩽0.95 μM. We applied our SAR models to various drug-like databases and identified novel chemical scaffolds for NS5B inhibitors. Subsequent in vitro antiviral assays suggested a new activity for an existing prodrug, Candesartan cilexetil, which is currently used to treat hypertension and heart failure but has not been previously tested for anti-HCV activity. We also identified NS5B inhibitors with two novel non-nucleoside chemical motifs.
Searching for silenced voices in Appalachian music

Music is extremely important in representations of place in the Appalachian Region of the United States, where ballads and banjo tunes become musical signposts in popular and academic culture to mark the region’s Otherness. Embedded in the discourse about the region and its music are silences about groups of people that do not fit dominant expectations of authenticity or belonging, the Others within. This essay serves to highlight some historical contributions of these groups, the social processes that have silenced them, and directions for future research to amplify those voices.
Dislocation Relaxation Spectra of Cold-Worked Body-Centered Cubic Transition Metals

Results are presented concenning the defect structure introduced into bcc transition metals by cold work. Peaks were found in the internal frictlon vs temperature curves of Nb, Ta, Mo, and W. Data are shown on specimens of these metals which were given a 3% tensile prestrain at 300 deg K (~ 600 deg K for W). Other data are included on fine-grained Mo prestrained 1%. (J.R.D.)
Can Germany Survive Without Nuclear Power

Confronted with stringent goals for greenhouse gas emissions reductions, germany is trying to find the right balance of energy sources and efficiency measures to meet electricity demand. Nuclear may or may not be part of the mix.
Role of imipenem/cilastatin in the treatment of soft tissue infections.

Abstract Imipenem/cilastatin was given to 243 evaluable patients with moderately severe to severe soft tissue infections. Cultures prior to therapy yielded Staphylococcus aureus (108 isolates), group D and non-group D enterococci (49), group A streptococci (42), other aerobic gram-positive cocci (72), Pseudomonas aeruginosa (54), Escherichia coil (32), Proteus mirabilis (31), Enterobacter (21), Klebsiella (20), other aerobic gram-negative rods (58), Bacteroides fragilis group (16), and other anaerobes (65). Overall, 95 percent (230 of 243) of the patients treated had clinical cure (137 of 243) or improvement (93 of 243). Of the 506 strains of etiologic bacterial pathogens isolated from these patients and tested against imipenem, 498 (98 percent) were susceptible to the antibiotic. Many were resistant to both older and newer penicillins and cephalosporins. Serial cultures of infection sites revealed that 426 of 498 (86 percent) of pre-therapy bacterial isolates were eradicated by imipenem/cilastatin therapy. Eight of 498 etiologic pathogens (1.6 percent) acquired resistance to imipenem (seven P. aeruginosa and one enterococcus). Such resistance acquisition was associated with clinical failure in two patients. Imipenem/cilastatin appears to be a highly effective, relatively safe therapy of soft tissue infections caused by a wide variety of gram-positive and gram-negative aerobes and anaerobes, both polymicrobial and monomicrobial in nature. Imipenem/cilastatin should be considered particularly when infection by the more antibiotic-resistant of these bacteria is suspected or proved.
Recent advances in modeling of traveling wave tubes

Traveling wave tubes (TWTs) remain the amplifiers of choice in many ground and space-based applications requiring the production of broadband high frequency microwave and millimeter wave power with high efficiency. All modern TWTs are designed using sophisticated computer-based design tools that are based on the fundamental physical laws governing the emission, transport, interaction, and collection of electron beams. This paper provides an overview of a state-of-the-art suite of modeling and design tools for the end-to-end simulation of coupled-cavity and helix traveling wave tubes.
A C-terminal Mutant of the G Protein β Subunit Deficient in the Activation of Phospholipase C-β

Abstract The molecular mechanism by which the G protein βγ complex modulates multiple mammalian effector pathways is unknown. Homolog-scanning mutagenesis of the G protein β subunit was employed to identify residues critical for the activation of phospholipase C-β2 (PLC-β2). A series of chimeras was made by introducing small segments of the Dictyostelium β subunit into a background of mammalian β1 and tested in COS cell cotransfection assays for their ability to activate PLC-β2 and assemble with mammalian γ2. A chimera that contained four Dictyostelium β substitutions within the C-terminal 14 residues was unable to activate PLC-β2 when cotransfected with γ, despite its demonstrable expression in a γ-dependent manner. Cotransfection of the mutant blocked m2 muscarinic receptor activation of PLC by a pertussis toxin-sensitive pathway. This C-terminal mutant retained the ability, however, to stimulate the mitogen-activated protein kinase pathway. These results imply that activation of different βγ-responsive effectors is mediated by distinct domains.
Mouse submandibular gland morphogenesis: a paradigm for embryonic signal processing.

Signal processing is the sine qua non of embryogenesis. At its core, any single signal transduction pathway may be understood as classic Information Theory, adapted as an open system such that, because of networking, the "receiver" is presented with more information than was initially signaled by the "source". Over 40 years ago, Waddington presented his "Epigenetic Landscape" as a metaphor for the hierarchical nature of embryogenesis. Mathematically, Waddington's landscape may be modeled as a neural net. The "black box" of the neural net is an interacting network of signal transduction pathways (using hormones, growth factors, cytokines, neurotransmitters, and others) which inform the Boolean logic gates. An emerging theme in developmental biology is that defined sets of epigenetic circuits are used in multiple places, at multiple times, for similar and sometimes different purposes during organogenesis. As we show here, submandibular gland embryonic and fetal development is a splendid paradigm of these ep...
Electrophoretic heterogeneity and relationships of pepsinogens in human urine, serum, and gastric mucosa.

The molecular forms of pepsinogen in urine and their relationship to six of the seven pepsinogens in gastric mucosa have been examined by an electrophoretic method. Pepsinogen (Pg) 1 is present in low concentration in mucosa and urine and was not considered in this study. Of 180 individuals without known renal or peptic ulcer disease, 152 were found to excrete Pg 2, Pg 3, Pg 4, and Pg 5 and 28 were found to excrete only Pg 2, Pg 3, and Pg 4. These two patterns, which have been designated A and B, respectively, have been shown to be absolutely constant for the individual. Of 23 subjects from whom gastric mucosa was available, 19 had Pg 2, Pg 3, Pg 4, and Pg 5 in both their mucosa and urine, while 3 had only Pg 2, Pg 3, and Pg 4 in their mucosa and urine. Only Pg 2 and Pg 3 were found in the mucosa of 1 subject who had Pg 2, Pg 3, and Pg 4 in his urine; biopsies from this individual revealed moderately severe atrophic gastritis. Pg 6, Pg 7, or both were found in the urine of only 8 of the 180 control subjects, 5 of whom had proteinuria. These pepsinogens were found in 13 of 15 patients with renal disease and proteinuria. The demonstration of Pg 6 and Pg 7 in serum and the failure to find an inhibitor of these zymogens in urine suggests that the usual absence of these zymogens in normal urine is due neither to their failure to enter the circulation nor to their inhibition by urine.
A low-power high performance polygon renderer for computer graphics

Polygon rasterization is one of the most computational and memory intensive operations in computer graphics. In this paper, we present a low-power, real-time hardware design for this task. The system is resolution-independent by configuring different numbers of render engines in a 2-dimensional array. Using an array configuration of 16 render engines for a 512×512-pixel display, a peak performance of up to 3.4 million Gouraud-shaded polygons/sec is achievable. Total power consumption, depending on the polygon throughput, ranges between 17 mW to 133 mW at 1.5 V operation. A format for transmitting polygon information is proposed at a typical bandwidth of 4 Mbps, suitable for wireless transmission. This screen and format configurable design has potential application in portable, wireless head-mounted displays for virtual reality systems.
Understanding the Role of Planners in Wildfire Preparedness and Mitigation

As wildfires affect more residential areas across the United States, the need for collaboration between land managers, federal agencies, neighbours, and local governments has become more pressing especially in the context of the wildland-urban interface. Previous research has not focused much on land-use planners’ role in wildfire mitigation. This paper provides information on how land-use planners can assist communities in learning to live with wildfire risk through planning, preparedness, and mitigation efforts in the wildland-urban interface (WUI). Based on interviews with land-use planners, forest planners, and local emergency management officials, we identified a range of tools that could be used for improving wildfire preparedness and mitigation initiatives in the WUI, but also found that planners felt that they lacked the regulatory authority to use these tenaciously. The paper also identifies a range of possible actions that would contribute towards safer building practices in the interface communities.