cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamic network signal processing using latent threshold models

We discuss multivariate time series signal processing that exploits a recently introduced approach to dynamic sparsity modelling based on latent thresholding. This methodology induces time-varying patterns of zeros in state parameters that define both directed and undirected associations between individual time series, so generating statistical representations of the dynamic network relationships among the series. Following an overview of model contexts and Bayesian analysis for dynamic latent thresholding, we exemplify the approach in two studies: one of foreign currency exchange rate (FX) signal processing, and one in evaluating dynamics in multiple electroencephalography (EEG) signals. These studies exemplify the utility of dynamic latent threshold modelling in revealing interpretable, data-driven dynamics in patterns of network relationships in multivariate time series.
Electroreduction of Oxygen by Cytochrome c Oxidase Immobilized in Electrode-Supported Lipid Bilayer Membranes

Cytochrome c oxidase is the terminal enzyme in mammalian respiration, and one of its main functions is to catalyze the reduction of oxygen under physiological conditions. Direct reduction of oxygen at electrodes requires application of substantial overpotentials. In this work, bovine cytochrome c oxidase has been immobilized in electrode-supported lipid bilayer membranes to investigate the electroreduction of oxygen under flow conditions. The effect that temperature, solution pH, and solution composition have on the reduction of oxygen by this novel enzyme-modified electrode is reported. Results indicate that the electroreduction of oxygen is most pronounced at low pH (6.4) and elevated temperature (38 degrees). At an applied potential of -350 mV vs. Ag/AgCl (1M KCl), a current density of ca. 7 microA/cm2 was obtained. The current responses obtained at these electrodes are stable over a period of ca. 10-14 days (10-15% decrease in response). The cytochrome c oxidase-modified electrodes described here could potentially be used for the direct electroreduction of oxygen to water in a biofuel cell.
Neonatal Damage of the Ventral Hippocampus Impairs Working Memory in the Rat

We investigated if a developmental lesion of the ventral hippocampus, studied previously as an animal model of schizophrenia, impairs performance in working memory tests related to the prefrontal cortex. Adult rats with a neonatal or adult excitotoxic lesion of the ventral hippocampus were tested in a continuous delayed alternation and a discrete paired-trial variable-delay alternation task. Performance of rats with the neonatal lesion was impaired as compared with control rats on both tasks, whereas performance of rats with the adult lesion was not altered in either task. The pattern of impaired performance, that worsened with increasing delays in neonatally lesioned rats, resembled that reported previously in animals with adult lesions of the medial prefrontal cortex. These results indicate that an early developmental, but not adult hippocampal, insult impairs performance in tasks sensitive to the integrity of the prefrontal cortex, and suggest that working memory may be compromised by neonatal damage of the ventral hippocampus.
Adaptive control of flexible joint manipulators: comments on two papers

Abstract We discuss two papers [Spong, M. W. (1989) Syst. Control. Lett. , 13 , 15–21; Chang, Y.-Z. and R. W. Daniel (1992) Automatica , 28 , 969–974] on the adaptive control of flexible joint robot manipulators. Our goal is to clarify the contributions of the two papers by correcting some technical errors and to provide some additional insight into the application of singular perturbation methods for the control of flexible joint robots.
Evaluation of Porter's constant

Abstract A 40D value is computed for the constant which J. W. Porter has recently derived in connection with the analysis of Euclid's algorithm.
One-pot three-enzyme chemoenzymatic approach to the synthesis of sialosides containing natural and non-natural functionalities

Chemoenzymatic synthesis, which combines the flexibility of chemical synthesis and the high selectivity of enzymatic synthesis, is a powerful approach to obtain complex carbohydrates. It is a preferred method for synthesizing sialic acid-containing structures, including those with diverse naturally occurring and non-natural sialic acid forms, different sialyl linkages and different glycans that link to the sialic acid. Starting from N-acetylmannosamine, mannose or their chemically or enzymatically modified derivatives, sialic acid aldolase-catalyzed condensation reaction leads to the formation of sialic acids and their derivatives. These compounds are subsequently activated by a CMP-sialic acid synthetase and transferred to a wide range of suitable acceptors by a suitable sialyltransferase for the formation of sialosides containing natural and non-natural functionalities. The three-enzyme coupled synthesis of sialosides can be carried out in one pot without the isolation of intermediates. The time for synthesis is 4-18 h. Purification and characterization of the product can be completed within 2-3 d.
Electrical resistance change in compact tension specimens of carbon fiber cement composites

The incorporation of a small volume of carbon fibers into a cement matrix can lead to multiple benefits including improvements in durability and tensile strength. In this paper, the smart material property of the composite which is its ability to respond to electrical stimuli was exploited. It was found that electrical resistance techniques which had previously been only applicable as investigative tools in fracture mechanics studies of metals could now be extended to the field of carbon fiber-reinforced concrete fracture mechanics. Compact-tension specimens of carbon fiber-reinforced mortar with volume percentages between 0% and 0.6% were tested. Fixed frequency electrical resistance measurements of 20 Hz, 100 Hz, 10 kHz and 1 MHz were taken during the tests. Good correlations between the electrical resistance behavior and mechanical behavior were observed. In particular, the electrical resistance may be used to provide some insight on the development and the mechanisms of the fracture process zone, and to provide an estimate of the length of a propagating crack. In addition, the tensile strength of the carbon fiber-reinforced mortar with 0.6% by volume of fibers increased by approximately three times over that of the unreinforced matrix.
Dynamic analysis of a ten-story reinforced concrete building using a continuum model

During the 1989 Loma Prieta earthquake, accelerometers maintained by the California Division of Mines and Geology Strong Motion Instrumentation Program (CSMIP) recorded the response of a 10-story, reinforced-concrete building located in San Jose, California. In this paper, a computationally efficient, approximate, dynamic analysis of the building is conducted utilizing a reduced-order continuum model. Continuum methodology makes use of the repetitive nature of lattice framing systems to generate finite element models having significantly fewer degrees of freedom than models generated using classical discrete finite element techniques. The vibrational characteristics of the continuum model, as well as the results of dynamic analyses, are compared to information gained from the recorded response of the building. The continuum model proves to be quite accurate, both in capturing the dominant periods of vibration of the structure and in predicting the time-history response. As a result, the method shows promise as a tool for use in the analysis and design of large lattice structures subjected to earthquake loads.
Fabrication of low-noise carbon nanotube field-effect transistor biosensors

We report the fabrication of suspended carbon nanotube field effect transistors (CNT FETs) designed for biological sensing applications. We compare the electrical properties of our suspended CNT FET design to standard surface based CNT FETs. In particular, we show a reduction in environmental noise, suggesting that the new sensor design is a promising candidate for low-noise sensing applications.
Hydrogen-atom abstraction from alkanes by OH. I. Neopentane and neooctane

Absolute rate coefficients for reactions of the hydroxyl radical with neopentane, perdeuteroneopentane, and neooctane were measured with the laser photolysis/laser-induced fluorescence technique. Experiments were performed at 400 torr helium pressure over the temperature range 287–903 K. The data were fit to modified Arrhenius expressions of the form k(T)=ATn exp (−E/RT). From this study, it was found that common parameters could be used to characterize the kinetics of the three reactions. For the OH/neopentane system, an increase in the reaction activation barrier of ≈947 cal/mole resulted upon deuterium substitution in neopentane. Theoretical calculations of this energy shift were performed and excellent agreement with experiment was obtained.
Optimal tax treatment of private contributions for public goods with and without warm glow preferences

Abstract Tax-favored contributions for financing some public goods may be a useful part of optimal nonlinear income tax and expenditure policy. There are two sides to the potential gain from subsidized donations. First, for a given level of public good provision, higher private donations from high earners than low earners eases the incentive compatibility constraint for donors and so can raise social welfare. This follows since considering a lower-paid job includes a perception of a drop in public good provision. Second, private donation reduces consumption, easing the resource constraint. This paper explores optimal policy, using first a model with standard preferences and then a model with a warm glow of giving. In addition to showing the conditions for the level of public goods, the paper considers the pattern of optimal subsidization across earnings levels. Analysis of optimal taxation with warm glow preferences is sensitive to the choice of preferences that are relevant for a social welfare evaluation. After considering optimal rules with formulations of social welfare which do and do not include warm glow utility, the paper considers the choice of normative criterion. Like the earlier literature, this paper assumes that organizing private donations is costless while tax collection has a deadweight burden. Since private charitable fundraising is very far from costless, the paper is an exploration of economic mechanisms, not a direct guide to policy.
An interpolation based approach for lighting variation in image recognition

We present an interpolation based approach to model the variation of illumination in images. Our approach allows for both synthesis and analysis of images in different lighting conditions. Hence, our model is a compact representation of the set of all images with the lighting conditions defined within a parametric space. Based on this approach, we propose image recognition methods to consider varying illumination conditions. We evaluate our recognition methods with an object image dataset and with the Yale extended face database. With our object image dataset we obtained a 99.53% recognition rate. The face recognition method proved to be robust and performed on par with the current state of the art algorithms in terms of recognition rate. We recorded an overall 91.92% recognition rate by testing every single image (including the ones with extreme lighting conditions) against the rest of the dataset. Furthermore, our model is general and can be extended to handle geometry and any other imaging parameters.
When the Rivers Run Dry: Water—The Defining Crisis of the Twenty-First Century

Since the publication of Marc Reisner's Cadillac Desert in 1986, multiple books, documentaries, and popular magazine articles have warned of current and impending water problems in the United States and around the world. In the past year alone (since October 2007, as this review is being written), there have been cover stories or major articles on this topic in the New Yorker , Newsweek , Time , U.S. News and World Report , and Vanity Fair . As anyone who has paid attention will know, high-profile issues include access to potable water and sanitation in developing countries, overpumping of aquifers, effects of land use and river engineering on aquatic ecosystems, and impacts of climate change on water resources. One of the most recent book-length overviews is When the Rivers Run Dry by Fred Pearce, the environment and development consultant for the British magazine New Scientist . Pearce offers an engaging, wide-ranging collection of cautionary tales about the uses and limits …
The Silent Epidemic of Thiazide‐Induced Hyponatremia

Hyponatremia is a recognized complication of treatment with thiazide diuretics, particularly in patients older than 70 years. Severe and symptomatic hyponatremia requires urgent management, usually requiring infusion of normal or hypertonic saline. Milder, asymptomatic, thiazide-induced hyponatremia requires steps to manage the hyponatremia as well as to prevent its future recurrence. This is a particular problem in patients who despite a history of thiazide-induced hyponatremia might require a diuretic in the management of their hypertension. In this review, the acute management of symptomatic and asymptomatic thiazide-induced hyponatremia is reviewed. Emphasis is also placed on the chronic management of patients who have experienced mild hyponatremia, in whom decisions about treatment with diuretic and nondiuretic antihypertensive agents must be made to satisfy the twin goals of controlling hypertension and avoiding recurrent hyponatremia.
Duration of lactation and maternal metabolism at 3 years postpartum.

Abstract Objective: Lactation has been associated with reduced risk of type 2 diabetes and the metabolic syndrome in mothers. We examined the relation between breastfeeding duration and metabolic markers at 3 years postpartum. Methods: We used linear regression to relate duration of lactation to maternal glucose and lipid metabolism, inflammatory markers, and anthropometry at 3 years postpartum among 570 participants with 3-year blood samples (175 fasting) in Project Viva, a cohort study of mothers and children. Results: Among the participants, 88% had initiated breastfeeding, and 26% had breastfed ≥12 months. In multivariate analyses, we observed no consistent trends relating duration of lactation to maternal metabolism at 3 years postpartum. Women who exclusively breastfed for >6 months had lower postpartum weight retention at 3 years than women with shorter durations of exclusive breastfeeding (multivariate adjusted predicted mean −0.5, −3.6–2.6 kg vs. 4.8, 2.0–7.6 kg for those who never exclusively br...
Infant Vocal Development in a Dynamic Mother-Infant Communication System

This study is an investigation of the development of infant vocalization in a changing and dynamic mother-infant communication system. Thirteen infants and their mothers were observed weekly from 4 to 24 weeks of age in a face-to-face interaction situation. Three patterns of mother-infant communication dynamics were classified: symmetrical (mutual engagement by mother and infant), asymmetrical (mother active while infant inactive), and unilateral (mother active while infant disengaged). Two types of infant nondistress vocalizations were categorized: syllabic (speechlike) and vocalic (nonspeechlike) vocalizations. It was hypothesized that the quantity and quality of infant nondistress vocalizations are associated with the patterns of mother-infant communication and that these associations change developmentally. The results demonstrated that the rates of syllabic and vocalic vocalizations were positively associated with symmetrical communication but negatively associated with unilateral communication. Syll...
Mushahara: A Nubian Concept of Supernatural Danger and the Theory of Taboo

The religous system of the Egyptian Nubians is a syncretistic complex of orthodox and popular Islam and "pagan" elements. Mushahara is a "pagan" concept referring to supernatural harm caused to individuals in vulnerable states by other persons' violation of taboos. Analysis of mushahara behavior reveals that it is oriented around life-cycle crises and the fear of spirit-beings. Functional anthropological and Freudian approaches appear to have some applicability in explaining the customs and changes in customs, but they leave major theoretical and methodological problems unsolved. In conclusion, an attempt is made to describe the nature of taboo.
Meeting the needs of medical research with statistical methods

Submit your manuscript here: http://www.dovepress.com/open-access-medical-statistics-journal Open Access Medical Statistics is an international, peerreviewed, open access journal publishing original research, reports, reviews and commentaries on all areas of medical statistics. The manuscript management system is completely online and includes a very quick and fair peer-review system. Visit http://www.dovepress.com/testimonials.php to read real quotes from published authors.
On the extensions of Gauss-Markov theorem to subsets of the parameter space under complex multivariate linear models

In this paper we continue the study of the extension of the Gauss-Markov theorem to certain general kinds of multiresponse models. In particular we obtain necessary and sufficient conditions, for the general incomplete multiresponse (GIM) model and the multiple design multi-response (MDM) model, such that unique best linear unbiased estimates (BLUE's) exist for all elements in a subset of the set of all estimable linear functions of the location parameters. Also the theory is illustrated by a couple of nontrivial examples.
Abca7 Null Mice Retain Normal Macrophage Phosphatidylcholine and Cholesterol Efflux Activity despite Alterations in Adipose Mass and Serum Cholesterol Levels

Mutations in the A class of ATP-binding cassette transporters (ABCA) are causally implicated in three human diseases: Tangier disease (ABCA1), Stargadt's macular degeneration (ABCA4), and neonatal respiratory failure (ABCA3). Both ABCA1 and ABCA4 have been shown to transport lipids across cellular membranes, and ABCA3 may play a similar role in transporting pulmonary surfactant. Although the functions of the other 10 ABCA class transporters identified in the human genome remain obscure, ABCA7-transfected cells have been shown to efflux lipids in response to stimulation by apolipoprotein A-I. In an effort to elucidate the physiologic role of ABCA7, we generated mice lacking this transporter (Abca7-/- mice). Homozygous null mice were produced from intercrosses of heterozygous null mice at the expected Mendelian frequency and developed normally without any obvious phenotypic abnormalities. Cholesterol and phospholipid efflux stimulated by apolipoprotein A-I from macrophages isolated from wild type and Abca7-/- mice did not differ, suggesting that these activities may not be central to the physiological role of the transporter in vivo. Abca7-/- females, but not males, had significantly less visceral fat and lower total serum and high density lipoprotein cholesterol levels than wild type, gender-matched littermates. ABCA7 expression was detected in hippocampal and cortical neurons by in situ hybridization and in brain and white adipose tissue by Western blotting. Induction of adipocyte differentiation from 3T3 fibroblasts in culture led to a marked increase in ABCA7 expression. These studies suggest that ABCA7 plays a novel role in lipid and fat metabolism that Abca7-/- mice can be used to elucidate.
Effectiveness of tobramycin conjugated to iron oxide nanoparticles in treating infection in cystic fibrosis

Cystic fibrosis (CF) is an inherited childhood-onset life-shortening disease. It is characterized by increased respiratory production, leading to airway obstruction, chronic lung infection and inflammatory reactions. The most common bacteria causing persisting infections in people with CF is Pseudomonas aeruginosa . Superparamagnetic Fe3O4 iron oxide nanoparticles (NPs) conjugated to the antibiotic (tobramycin), guided by a gradient of the magnetic field or subjected to an oscillating magnetic field, show promise in improving the drug delivery across the mucus and P. aeruginosa biofilm to the bacteria. The question remains whether tobramycin needs to be released from the NPs after the penetration of the mucus barrier in order to act upon the pathogenic bacteria. We used a zero-length 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) crosslinking agent to couple tobramycin, via its amine groups, to the carboxyl groups on Fe 3 O 4 NPs capped with citric acid. The therapeutic efficiency of Fe 3 O 4 NPs attached to the drug versus that of the free drug was investigated in P. aeruginosa culture.
Effects of ethanol and ipsapirone on the expression of genes encoding anti-apoptotic proteins and an antioxidant enzyme in ethanol-treated neurons.

Abstract Previously, this laboratory found that apoptosis was augmented significantly in fetal rhombencephalic neurons when they were treated with 50 mM ethanol for 24 h. These changes were associated temporally with a reduction in the phosphatidylinositol 3-kinase (PI3K) pro-survival pathway and in the downstream expression of several NF-κB dependent anti-apoptotic genes. The serotonin-1A agonist ipsapirone prevented ethanol-associated apoptosis; it also activated the PI3K → pAkt pro-survival pathway and the expression of specific NF-κB dependent anti-apoptotic genes in ethanol-treated neurons. The present study investigated the temporal effects of both ethanol and ipsapirone on the expression of three NF-κB dependent genes, XIAP , Bcl- xl and catalase ; these genes encode proteins that could potentially attenuate ethanol-induced apoptosis. Catalase activity was also measured. All three genes demonstrated an early activation by ethanol. After a brief treatment with 50 mM ethanol, i.e., 2 to 8 h depending on the gene, the expression of XIAP , Bcl- xl , and catalase was significantly increased, possibly as an initial attempt to survive. An ethanol-associated increase in catalase was followed by a rise in catalase activity. However, when ethanol treatment was continued for a longer time, there was a significant reduction in both XIAP and Bcl- xl . In addition, both catalase expression and activity returned to levels found in unstressed controls. Importantly, treatment with ipsapirone augmented the activity of catalase and the expression of Bcl- xl , XIAP , and catalase in ethanol-treated neurons at later time points. The latter effects are likely to contribute to the pro-survival effects of ipsapirone.
Managing complex data and geometry in parallel structured AMR applications

Adaptive mesh refinement (AMR) is an increasingly important simulation methodology for many science and engineering problems. AMR has the potential to generate highly resolved simulations efficiently by dynamically refining the computational mesh near key numerical solution features. AMR requires more complex numerical algorithms and programming than uniform fixed mesh approaches. Software libraries that provide general AMR functionality can ease these burdens significantly. A major challenge for library developers is to achieve adequate flexibility to meet diverse and evolving application requirements. In this paper, we describe the design of software abstractions for general AMR data management and parallel communication operations in SAMRAI, an object-oriented C++ structured AMR (SAMR) library developed at Lawrence Livermore National Laboratory (LLNL). The SAMRAI infrastructure provides the foundation for a variety of diverse application codes at LLNL and elsewhere. We illustrate SAMRAI functionality by describing how its unique features are used in these codes which employ complex data structures and geometry. We highlight capabilities for moving and deforming meshes, coupling multiple SAMR mesh hierarchies, and immersed and embedded boundary methods for modeling complex geometrical features. We also describe how irregular data structures, such as particles and internal mesh boundaries, may be implemented using SAMRAI tools without excessive application programmer effort.
Mechanical tension modulates local and global vesicle dynamics in neurons

Growing experimental evidence suggests that mechanical tension plays a significant role in determining the growth, guidance, and function of neurons. Mechanical tension in axons contributes to neurotransmitter clustering at the Drosophila neuromuscular junction (NMJ) and is actively regulated by neurons both in vitro and in vivo. In this work, we applied mechanical strain on in vivo Drosophila neurons and in vitro Aplysia neurons and studied their vesicle dynamics by live-imaging. Our experiments show that mechanical stretch modulates the dynamics of vesicles in two different model systems: (1) The global accumulation of synaptic vesicles (SV) at the Drosophila NMJ and (2) the local motion of individual large dense core vesicles (LDCV) in Aplysia neurites. Specifically, a sustained stretch results in enhanced SV accumulation in the Drosophila NMJ. This increased SV accumulation occurs in the absence of extracellular Ca2+, plateaus after approximately 50 min, and persists for at least 30 min after stretch is reduced. On the other hand, mechanical compression in Aplysia neurites immediately disrupts LDCV motion, leading to decreased range and processivity. This impairment of LDCV motion persists for at least 15 min after tension is restored. These results show that mechanical stretch modulates both local and global vesicle dynamics and strengthens the notion that tension serves a role in regulating neuronal function.
Trends in wireless sensor networks for manufacturing

Wireless communications in general, Wireless Sensor Networks and Radio-Frequency Identification (RFID) constitute a family of technologies for delivering an increased spatial density of sensors, local computation at the sensor-node and the potential for distributed and fault-tolerant monitoring. This paper focuses on wireless sensor nodes and networking. Nodes can be mounted on various parts of machinery and plant to promote early fault detection and analysis. Their small size and autonomy enables their placement in locations that are usually difficult to access. In addition, it is also possible, with minimal changes to the machine configuration, to deploy sensors on the machinery after it has been installed. The sensor nodes not only monitor their own output but also collaborate with neighbouring nodes to determine the health of the overall machines and provide early warnings of potential failure. The paper discusses the uses of these networks and the issues that must be addressed for successful implementations.
Expert and novice differences in strategies to problem solve an environmental issue

Abstract Differences between environmental experts and four environmental novice groups (three academic and one student), N = 85, in use of problem solving strategies of reasoning, subproblem breakdown, problem development, solution development, and exploring solution implications when verbally responding to an energy environmental issue were investigated. The results showed that environmental experts scored significantly higher than environmental novices in use of all problem solving strategies except subproblem development. These results imply that strategies to problem solve multidisciplinary issues are domain-specific skills; skills not acquired by generalizing skills from related domains. Therefore they require special development.
Short term changes in sex ratio and density alter coercive male mating tactics

Short term fluctuations in operational sex ratio (OSR) and density can strongly influence male mating, often exacerbating conflict between males and females. Livebearing fishes of the genus Gambusia are ideal for investigating sexual conflict because males of all sizes mate coercively. In this study, we tested how short-term fluctuations in OSR and density influence coercive male mating behaviours. Specifically, we tested the prediction that as OSR becomes more female biased, males will mate with all available females. In contrast, as OSR becomes more male biased, male aggression will inhibit mating frequency. As predicted, males mated with more females as the number of available females increased. Moreover, males were less aggressive as the proportion of females increased and more aggressive as the number of males increased. This resulted in an inverse relationship between mating and aggression with OSR and density. Coercive males attempt to maximize their reproductive success by mating with all available females, which supports classic theory on the impact of OSR and density on reproductive activity.
The gestalt of scientific programming: problem, model, method, implementation, assessment

The process of solving a problem in computational science neither begins nor ends with designing and writing a computer program. The process entails isolating the problem, devising a mathematical model, identifying a computational method, producing an implementation, and assessing the solution. Unfortunately, the introductory programming courses taken by science and engineering students frequently focus only on implementation issues. As a result, such students are often ill-equipped to solve computational problems.We have created a course and written an accompanying textbook that present an introduction to scientific programming. Both are organized around the process for solving computational science problems sketched above. In this paper we illustrate this approach by describing two representative problems from the course and textbook. Along the way, we present Java applets that were designed to illustrate some of the ideas that underlie the two problems.
Low-latitude thermal structure of Jupiter in the region 0.1-5 bars

Abstract The radiative heat flux from 0.1 to 10 bars is estimated on the basis of a “two-cloud” scattering model that fits available spectral data and Pioneer photometry. Deeper than a few bars, the flux is 4.5 W m −2 , compared with the 18.8 W m −2 used in an earlier study by Trafton and Stone. A temperature profile is computed, with the H 2 pressure-induced opacity; the temperature at 1 bar is found to be 156°K, rather than the commonly accepted 170°K. An additional optical depth of unity at the 0.67-bar level could restore the conventional value; otherwise a considerably cooler atmosphere is a serious possibility.
Characterization of Young’s Modulus of Nanowires on Microcantilever Beams

A new approach to measure the elastic modulus of nanowires is presented in this paper using a nanowire and a microcantilever beam composite system. The mechanical behavior of a nanowire-microcantilever beam structure under electrostatic actuation was studied using the finite element method, and a comparison of the resonance frequencies for a nanowire-microcantilever composite beam structure and a microcantilever beam only is presented. The test system can be optimized by introducing arrays of nanowires to increase the resonance frequency difference between the microcantilever beams and the nanowire array microbeam structures.
NGC 6543: The Rings Around the Cat's Eye

Hubble archival images of NGC 6543 reveal a series of at least nine regularly spaced concentric circular rings that surround the famous nebular core, known as the Cat's Eye Nebula. The rings are almost certainly spherical bubbles of periodic isotropic nuclear mass pulsations that preceded the formation of the core. The bubbles are detected solely in the lines of Hα, [O III], and [N II]. The core and the bubbles around it appear to have very similar temperature, ionization, and chemical properties. Assuming a distance of 1 kpc and an outflow velocity of 10 km s-1, a good fit to the Hα surface brightness distribution suggests that the bubbles were ejected with constant mass (~0.01 M⊙) and thickness (~1000 AU) approximately every 1500 years. The combined mass of the visible bubbles, ~0.1 M⊙, is comparable to that of the present mass of the core (~0.05 M⊙). Since the bubbles are evenly spaced and there is no sign of bubble-bubble collisions, the bubble ejection mechanism regulates the outflow speed to better than 10%. The line widths of the bubbles, ~30 km s-1, argue that the bubbles are in the process of thickening and merging on timescales 103 yr. Their ejection period is consistent with a suggestion that quasi-periodic shells are launched every few hundred years in dust-forming asymptotic giant branch (AGB) winds but not consonant with the predictions of extant models of core thermal pulses (~105 yr) and surface pulsations (~10 yr). It appears that regular isotropic AGB mass pulses can precede the formation of brighter, denser, and more complex planetary nebula cores that are formed when an abrupt change of mode of mass loss occurs. Disruptive binary companion mergers or the sudden emergence of a magnetic field might account for the mode change.
Speeder Reader: An experiment in the future of reading

Abstract Speeder Reader is an interactive reading station built around two primary ideas: dynamic text (especially RSVP, that is, rapid serial visual presentation), and the interface metaphor of driving. As words flash one at a time on a screen in front of the reader, he or she controls the rate of speed of the words with a gas pedal (up to 1850 words per minute in the current instance). Text stream selection is performed with a steering wheel. Thus, one can “drive through a book”. We leverage people's knowledge of the familiar activity of driving an automobile (or, in the case of children, operating a speed-racing video game) to allow comfortable and intuitive access to a possibly less familiar world of interactive text. We emphasize the power and ease of the familiar driving metaphor as a navigation device. Speeder Reader was first installed at the Tech Museum of Innovation in San Jose, CA, as part of a larger exhibit on the impact of digital technologies on reading.
SU-GG-T-90: Performance of Dual Layer Micro MLC Versus Standard Single Layer MLC for IMRT Delivery

Purpose: To evaluate the performance characteristics of a first‐of‐its‐kind dual layer micro multi‐leaf collimator (DmMLC) and compare it dosimetrically with standard, single layer MLCs for use in intensity modulated radiation therapy(IMRT).Method and Materials: The DmMLC performance was studied using a cross shaped field generated by both a single layer MLC and the DmMLC. The DmMLC by Initia Medical Technologies was mounted on a Varian 600C linac unit. Film measurements were obtained using a 6 MV x‐ray beam and EDR2 film at a depth of 5 cm in solid water at 100 cm source to film distance. Film analysis was performed using the RIT V5 software. The leaf‐end transmission of the single bank and dual bank of mMLC was measured. The maximum and average leaf‐end transmissions for the cross pattern were compared for both modes of operation of the mMLC and for the standard Varian MLC.Results: The leaf‐end transmission for the single layer of the DmMLC was at its maximum 22.4% with an average value of 15.4% The transmission was reduced to a maximum of 2.4% and an average of 2.1% when both layers of the DmMLC leaves were used. Dual layer MLC provided more conformal field edge as compared to the standard single layer MLC with approximately ten fold less transmission at the leaf end. Conclusion: The results of this study indicate that the DmMLC provides more precise field shaping at field edges than the standard MLC. The DmMLC reduces the leaf‐end transmission to about 2.1%. The dual layer MLC offers more accurate IMRTdelivery to the planned target volume and spares the underlined surrounding health tissue from increased transmission and leakage dose.Conflict of Interest: The work was partially supported by a research grant from Initia RT.
Preparation, culture, and analysis of amniotic fluid samples.

Amniotic fluid obtained via amniocentesis provides a source of fetal material used in prenatal diagnosis. The fluid may be used directly for biochemical analyses, fluorescence in situ hybridization (FISH), and isolation of DNA for molecular studies, including chromosomal microarray analysis (CMA). The fluid is typically cultured as a source of metaphase cells for chromosome analysis and to provide additional material for biochemical and DNA-based testing. This unit describes an in situ method for the preparation, culture, and harvest of amniotic fluid samples for metaphase chromosome analysis. Cells are grown, harvested for metaphase spreads, and analyzed on glass coverslips. The unit also describes methods to obtain cells for additional studies (such as molecular genetic analyses) by growing cells in flasks either following passaging of cells from a glass coverslip culture or by directly establishing a flask culture from the amniotic fluid specimen. When cells are grown in flasks, they must be removed from the flask with trypsin before they can be used in studies. Lastly, this unit describes a method for isolating DNA for CMA from uncultured amniotic fluid and cultured cells. © 2018 by John Wiley & Sons, Inc.
What Directions for Race/Ethnic Relations? Kaleidoscope of Options

American Minorities and Economic Opportunity. H. Roy Kaplan. Uncertain Americans: Readings in Ethnic History. 2nd ed. Leonard Dinnerstein and rederic Cople Jaher, eds. Ethnicity in the Americas. Frances Henry, ed. World Anthropology Series. Sol Tax, gen. ed. Ethnic Families in America: Patterns and Variations. Charles H. Mindel and Robert W. Habenstein, eds. Issues in Race and Ethnic Relations: Theory, Research and Action. Jack Rothman, ed. The Minority Report: An Introduction to Racial, Ethnic, and Gender Relations. Anthony G. Dworkin and Rosalind J. Dworkin. American Ethnic Revival: Group Pluralism Entering America's Third Century. Jack F. Kinton, ed.
Modeling End‐Use Quality in U.S. Soft Wheat Germplasm

ABSTRACT End-use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four U.S. regional nurseries. Selected parameters included test weight, kernel hardness, kernel size, kernel diameter, wheat protein, polyphenol oxidase activity, flour yield, break flour yield, flour ash content, milling score, flour protein content, flour SDS sedimentation volume, flour swelling volume, Rapid Visco Analyzer peak paste viscosity, solvent retention capacity (SRC) parameters, total and water-extractable arabinoxylan (TAX and WEAX, respectively), and cookie diameter. The objectives were to model cookie diameter and lactic acid SRC as well as to compare exceptionally performing varieties for each quality parameter. Cookie diameter and lactic acid SRC were modeled by using multiple regression analyses and all of the aforementioned quality parameters. Cookie diameter was positively associ...
Risks to forest carbon offset projects in a changing climate

When included as part of a larger greenhouse gas (GHG) emissions reduction program, forest offsets may provide low-cost opportunities for GHG mitigation. One barrier to including forest offsets in climate policy is the risk of reversal, the intentional or unintentional release of carbon back to the atmosphere due to storms, fire, pests, land use decisions, and many other factors. To address this shortcoming, a variety of different strategies have emerged to minimize either the risk or the financial and environmental implications of reversal. These strategies range from management decisions made at the individual stand level to buffers and set-asides that function across entire trading programs. For such strategies to work, the actual risk and magnitude of potential reversals need to be clearly understood. In this paper we examine three factors that are likely to influence reversal risk: natural disturbances (such as storms, fire, and insect outbreaks), climate change, and landowner behavior. Although increases in atmospheric CO 2 and to a lesser extent warming will likely bring benefits to some forest ecosystems, temperature stress may result in others. Furthermore, optimism based on experimental results of physiology and growth must be tempered with knowledge that future large-scale disturbances and extreme weather events are also likely to increase. At the individual project level, management strategies such as manipulation of forest structure, age, and composition can be used to influence carbon sequestration and reversal risk. Because some management strategies have the potential to maximize risk or carbon objectives at the expense of the other, policymakers should ensure that forest offset policies and programs do not provide the singular incentive to maximize carbon storage. Given the scale and magnitude of potential disturbance events in the future, however, management decisions at the individual project level may be insufficient to adequately address reversal risk; other, non-silvicultural strategies and policy mechanisms may be necessary. We conclude with a brief review of policy mechanisms that have been developed or proposed to help manage or mitigate reversal risk at both individual project and policy-wide scales.
Do preferences for charitable giving help auctioneers

Preferences for charitable giving in auctions can be modeled by assuming that bidders receive additional utility proportional to the revenue raised by an auctioneer. The theory of bidding in the presence of such preferences results in a very counterintuitive prediction which is that, in many cases, bidders having preferences for charitable giving does not lead to a substantial revenue advantage for an auctioneer. We test this theory and this prediction with a series of experiments. In one experiment we induce charitable preferences exactly as specified in the model to see if bidders respond to them as predicted. We find that they do. We then conduct a second experiment in which the revenue from the auctions is donated to actual charities to verify the robustness of the prediction when charitable preferences are generated by a more natural source and find again that the theoretical prediction holds: even strong charitable preferences do not result in substantial revenue increases to the auctioneer.
Improving Instructional Leadership Through the Development of Leadership Content Knowledge: The Case of Principal Learning in Algebra

Instructional leadership is integral to improving mathematics teaching in secondary schools. However, administrators often lack sufficient content knowledge in mathematics to be effective in this role. This study examined the impact of professional development focused on developing leadership content knowledge in algebra. Data included written assessments, case discussions, and interviews from 10 principals. Analysis identified shifts in principals’ algebra content knowledge and their frames for interpreting algebra instruction. Principles improved their connections between mathematical representations and shifted from using frames highlighting teacher characteristics toward using frames highlighting teacher and student thinking. Implications for leadership professional development design are discussed.
Second-Order Optimality Conditions in Nonlinear Programming Obtained by Way of Epi-Derivatives

Dedicated to the memory of Robin W. Chaney Second-order optimality conditions for finite-dimensional smooth and nonsmooth nonlinear programming are obtained by a new method that emphasizes a close connection with geometrical approximation of the essential objective function. The approximation is secured by the use of certain epi-derivatives defined by epiconvergence. The optimality conditions are expressed in a form that covers general interval constraints and their possible representation through penalties or an augmented Lagrangian. An abstract constraint involving restriction to a convex polyhedron is incorporated.
The Divergent AmoC3 Subunit of Ammonia Monooxygenase Functions as Part of a Stress Response System in Nitrosomonas europaea

The ammonia monooxygenase of chemolithotrophic ammonia-oxidizing bacteria (AOB) catalyzes the first step in ammonia oxidation by converting ammonia to hydroxylamine. The monooxygenase of Nitrosomonas europaea is encoded by two nearly identical operon copies (amoCAB1,2). Several AOB, including N. europaea, also possess a divergent monocistronic copy of amoC (amoC3) of unknown function. Previous work suggested a possible functional role for amoC3 as part of the σE stress response regulon during the recovery of N. europaea from extended ammonia starvation, thus indicating its importance during the exit of cells from starvation. We here used global transcription analysis to show that expression of amoC3 is part of a general poststarvation cellular response system in N. europaea. We also found that amoC3 is required for an efficient response to some stress conditions, as deleting this gene impaired growth at elevated temperatures and recovery following starvation under high oxygen tensions. Deletion of the σ32 global stress response regulator demonstrated that the heat shock regulon plays a significant role in mediating the recovery of N. europaea from starvation. These findings provide the first described phenotype associated with the divergent AmoC3 subunit which appears to function as a stress-responsive subunit capable of maintaining ammonia oxidation activity under stress conditions. While this study was limited to starvation and heat shock, it is possible that the AmoC3 subunit may be responsive to other membrane stressors (e.g., solvent or osmotic shocks) that are prevalent in the environments of AOB.
The Stanford University VLF Wave Injection Experiment on the ISEE-A Spacecraft

A Stanford University VLF wave injection experiment will be carried out as part of the ISEE mission. This experiment consists essentially of three basic components; a broad-band VLF receiver on ISEE-A, a broad-band VLF transmitter located at Siple Station in the Antarctic, and a number of ground stations in the Antarctic and Canada. This experiment is an outgrowth of VLF wave injection experiments carried out over the past four years using the Stanford University transmitter at Siple Station, Antarctica. The purpose of this experiment is to study VLF-wave-particle interactions in the magnetosphere, with the goal of achieving a better understanding of this important portion of the earth's environment. In the present paper we sketch briefly the scientific background of the experiment and describe the functions of the ISEE-A instrument.
High resolution three-dimensional reconstruction of photonic crystal structure found in beetle scales

In this paper we demonstrate how sequential FIB milling combined with scanning electron microscopy imaging can be used to achieve a previously unprecedented high-resolution 3D reconstruction of the photonic crystal structure found in beetle scales.
Driving energy efficiency with design optimization of a centrifugal fan housing system for variable frequency drives

Increasing demands for electrical equipment efficiency has renewed interest in improving the electrical and thermal efficiency of industrial equipment. Variable speed drives are typically air-cooled and fall under recent international standards for improved fan efficiency. This paper details the modeling, design optimization, and experimental verification approaches used to optimize blower housing designs for variable speed drives.
Receptor-mediated angiotensin II transcytosis by brain microvessel endothelial cells

Abstract Angiotensin II (Ang II) uptake and transport across monolayers of bovine brain microvessel endothelial cells (BMECs) was demonstrated. Ang II transport was linear up to 2 h, saturable with a K m of 1.7 nM, and tended to be polarized with the apical-to-basolateral transport being greater. [ 3 H]Ang II transport was found to be inhibited by excess unlabeled Ang II, by the Ang II analog sarathrin, and by the endocytic inhibitor phenylarsine oxide. Ang II-(2–8) and-(3–8) were shown to significantly increase the transport of Ang II. These results demonstrate for the first time the receptor-mediated transcytosis of Ang II across brain microvessel endothelium.