cssi/SciSciGPT-SciSciNet huggingface dataset:
Computational thinking and interdisciplinary encounters: keynote address

In an influential 2006 article, Jeanette Wing called for the elaboration of an approach to "computational thinking." Wing argued that computational thinking expresses the importance of computer science to general education, and provides a basis for interdisciplinary collaboration, by setting out the conceptual foundations of computational modeling and reasoning. In this talk, I want to reflect on alternative ways of approaching computational thinking as a site of disciplinary encounter, with a particular focus on the ways that interdisciplinary work might be generative of new forms of computational thinking. This work grows out of a collaboration with colleagues in Australia, whose research is focused on the use of information technology in the cultural practices of indigenous Australian groups, particularly the Yolngu of Northeast Arnhemland. Yolngu epistemology provides an interesting starting point for reconsidering aspects of computational practice, which suggests new perspectives on computational thinking and its practice, and on the possible relationship between computer science and other disciplines.
Sources of Response Bias in Cognitive Self-Report Items: "Which Memory Are You Talking About?"

Background and objectives Self-reported cognitive difficulties are common in the years before an Alzheimer's disease (AD) diagnosis. Understanding how older adults interpret and respond to questions about their cognition is critical to recognize response biases that may limit the accuracy of cognitive self-reports in identifying AD risk. Cognitive interviewing is a systematic approach for examining sources of response bias that influence individuals' answers to specific questions. The purpose of this study was to identify features of common cognitive self-report items that contribute to (a) differing interpretations among respondents and (b) older adults' decisional processes when responding. Research design and methods A convenience sample of community-dwelling older adults (n = 49; Mage = 74.5 years; 36.7% male) without dementia completed a demographic questionnaire, the Montreal Cognitive Assessment, and an audio-recorded cognitive interview. Twenty commonly used cognitive self-report items were evaluated using cognitive interviewing techniques. The Question Appraisal System was used to guide the analysis of interview data and identify sources of response bias within and across cognitive self-report items. Results The most common sources of inconsistency in item interpretation and decisional processes were vague item wording, incorrect assumptions regarding consistency of cognitive problems across situations, and provocation of an emotional reaction that influenced responses. Discussion and implications Assessment of self-reported cognition is critical to facilitate research on early AD symptoms. Findings from this study identify modifiable sources of response bias that may influence the measurement properties of currently used cognitive self-report items and can inform refinement of measures.
Parameter identifiability of a respiratory mechanics model in an idealized preterm infant

The complexity of mathematical models describing respiratory mechanics has grown in recent years to integrate with cardiovascular models and incorporate nonlinear dynamics. However, additional model complexity has rarely been studied in the context of patient-specific observable data. This study investigates parameter identification of a previously developed nonlinear respiratory mechanics model (Ellwein Fix, PLoS ONE 2018) tuned to the physiology of 1 kg preterm infant, using local deterministic sensitivity analysis, subset selection, and gradient-based optimization. The model consists of 4 differential state equations with 31 parameters to predict airflow and dynamic pulmonary volumes and pressures generated under six simulation conditions. The relative sensitivity solutions of the model state equations with respect to each of the parameters were calculated with finite differences and a sensitivity ranking was created for each parameter and simulation. Subset selection identified a set of independent parameters that could be estimated for all six simulations. The combination of these analyses produced a subset of 6 independent sensitive parameters that could be estimated given idealized clinical data. All optimizations performed using pseudo-data with perturbed nominal parameters converged within 40 iterations and estimated parameters within ~8% of nominal values on average. This analysis indicates the feasibility of performing parameter estimation on real patient-specific data set described by a nonlinear respiratory mechanics model for studying dynamics in preterm infants.
Patterns of Social-Emotional Needs and Trajectories of Aggression and Substance Use Among Middle School Boys:

Co-occurring social-emotional problems are associated with increased risk of aggression and substance use. However, few studies examine their configurational patterns. This study identifies pattern...
Face acquisition camera design using the NV-IPM image generation tool

In this paper, we demonstrate the utility of the Night Vision Integrated Performance Model (NV-IPM) image generation tool by using it to create a database of face images with controlled degradations. Available face recognition algorithms can then be used to directly evaluate camera designs using these degraded images. By controlling camera effects such as blur, noise, and sampling, we can analyze algorithm performance and establish a more complete performance standard for face acquisition cameras. The ability to accurately simulate imagery and directly test with algorithms not only improves the system design process but greatly reduces development cost.
Abstract 4488: Effector B cells and tertiary lymphoid structures predict response to immune checkpoint blockade in solid tumors

Background: Cytotoxic T cell markers, PD-L1, and mutational burden have been identified as biomarkers of response to immune checkpoint blockade (ICB). However, there is a growing appreciation of B cells as biomarkers and mediators of response. We recently conducted a phase II trial of neoadjuvant ICB (NCT02519322) in patients with resectable melanoma, and found increased B cell infiltration in responders (R) versus non-responders (NR). Methods: We further investigated our B cell findings through whole transcriptomic profiling in samples with high tumor purity and also targeted immune profiling with deconvolution algorithm MCP counter. Spatial organization of the B cells was assessed with singlet and multiplex immunohistochemistry (IHC). Additionally, B cell phenotype was queried through mass cytometry. B cell gene expression signatures were validated in a cohort of renal cell carcinoma (RCC) patients (NCT02210117), and B cell phenotype in a metastatic melanoma cohort, both treated with ICB. Results: Whole transcriptomic analysis of the neoadjuvant melanoma ICB cohort identified that the most differentially expressed genes by response in baseline (b/l) samples were related to B cells and antibody production (MZB1, JCHAIN, IGLL5, FCRL5, p Conclusion: Together, these data suggest that B cells, more specifically those with activated effector phenotypes, and TLS predict response to ICB and may also be contributing mechanistically to response. Citation Format: Sangeetha M. Reddy, Beth Helmink, Jianjun Gao, Shaojun Zhang, Keren Yizhak, Moshe Sade-Feldman, Rafet Basar, Jorge Blando, Guangchun Han, Vancheswaran Gopalakrishnan, Hao Zhao, Wenbin Liu, Hussein Tawbi, Rodabe Amaria, Michael Davies, Jeffrey Gershenwald, Elizabeth M. Burton, James Allison, Michael Tetzlaff, Katy Rezvani, Nir Hacohen, Padmanee Sharma, Linghua Wang, Jennifer Wargo. Effector B cells and tertiary lymphoid structures predict response to immune checkpoint blockade in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4488.
New Embodiments of Static Field Micro-Particle Components for Reconfigurable RF Applications

Static Field Micro-Particle Components (SFM-PCs) have been developed and used in different applications such as transmission lines (TL), antennas, and filters. As this technique does not require a biasing circuitry, it is a promising switching methodology for future radio frequency (RF) systems. In this paper, we propose two new techniques, Asymmetric Copper and Double Switch, to improve the performance of the SFM-PC which allow the use of this particle-based component in high-frequency wireless applications that may not be possible with the traditional structure. Both HFSS simulation and measurement results of embedding a 3.0 × 3.0 × 1.524 mm3 Double Switch Asymmetric Copper made of Rogers TMM4 on a host microstrip TL show that its frequency bandwidth for both ON and OFF states can reach up to 7.0 GHz, several times of the previously reported values, indicating the efficacy of the presented new methodologies.
Go International Gradually: Advice to Small Businesses from Companies with Overseas Experience

The limited resources of small businesses often present unique challenges when the companies try to internationalize. This paper examines the decision to enter the global arena from the viewpoint of firms who already are there. The results of a survey of such companies indicate that changes in the external situation often overcome internal reservations firms might have about internationalizing. Survey participants identify issues related to risk management and the assignment of responsibility for international operations as key areas of concern, and they suggest "coping strategies" for small businesses thinking about doing business overseas.
MRI texture analysis in acromegaly and its role in predicting response to somatostatin receptor ligands

Given the paucity of reliable predictors of tumor recurrence, progression, or response to somatostatin receptor ligand (SRL) therapy in acromegaly, we attempted to determine whether preoperative MR image texture was predictive of these clinical outcomes. We also determined whether image texture could differentiate somatotroph adenomas from non-functioning pituitary adenomas (NFPAs). We performed a retrospective study of patients with acromegaly due to a macroadenoma who underwent transsphenoidal surgery at our institution between 2007 and 2015. Clinical data were extracted from electronic medical records. MRI texture analysis was performed on preoperative non-enhanced T1-weighted images using ImageJ (NIH). Logistic and Cox models were used to determine if image texture parameters predicted outcomes. Eighty-nine patients had texture parameters measured, which were compared to that of NFPAs, while 64 of these patients had follow-up and were included in the remainder of analyses. Minimum pixel intensity, skewness, and kurtosis were significantly different in somatotroph adenomas versus NFPAs (area under the receiver operating characteristic curve, 0.7771, for kurtosis). Furthermore, those with a maximum pixel intensity above the median had an increased odds of IGF-I normalization on SRL therapy (OR 5.96, 95% CI 1.33–26.66), which persisted after adjusting for several potential predictors of response. Image texture did not predict tumor recurrence or progression. Our data suggest that MRI texture analysis can distinguish NFPAs from somatotroph macroadenomas with good diagnostic accuracy and can predict normalization of IGF-I with SRL therapy.
Potassium isotopic composition of the Moon

Abstract The Moon is depleted in water and other volatiles compared to Earth and the bulk solar composition. Such depletion of volatile elements and the stable isotope fractionations of these elements can be used to better understand the origin and early differentiation history of the Moon. In this study, we focus on the moderately volatile element, potassium, and we report the K elemental abundances and isotopic compositions (δ41K relative to NIST SRM 3141a) for nineteen Apollo lunar rocks and lunar meteorites (twenty-two subsamples), spanning all major geochemical and petrologic types of lunar materials. The K isotopic compositions of low-Ti and high-Ti basalts are indistinguishable, providing a lunar basalt average δ41K of –0.07 ± 0.09‰ (2SD), which we also consider to be the best estimate of the lunar mantle and the bulk silicate Moon. The significant enrichment of K in its heavier isotopes in the bulk silicate Moon, compared with the bulk silicate Earth (δ41K = –0.48 ± 0.03‰), is consistent with previous analyses of K isotopes and other moderately volatile elements (e.g., Cl, Cu, Zn, Ga, and Rb). We also report analyses of K isotopes for lunar nonmare samples, which show large variations of K isotopic ratios compared to lunar basalts. We interpret this large K isotopic fractionation as the result of late-stage magma ocean degassing during urKREEP formation, which is also coupled with Cl isotope fractionation. Degassing of urKREEP likely triggered redistribution of K isotopes in the Moon, enriching the urKREEP reservoir in heavy K isotopes while implanting the light K isotopic signatures onto the lunar surface. This scenario suggests a heterogeneous distribution of K isotopes in the Moon as a consequence of its magmatic evolution.
Food Classification with Convolutional Neural Networks and Multi-Class Linear Discernment Analysis.

Convolutional neural networks (CNNs) have been successful in representing the fully-connected inferencing ability perceived to be seen in the human brain: they take full advantage of the hierarchy-style patterns commonly seen in complex data and develop more patterns using simple features. Countless implementations of CNNs have shown how strong their ability is to learn these complex patterns, particularly in the realm of image classification. However, the cost of getting a high performance CNN to a so-called "state of the art" level is computationally costly. Even when using transfer learning, which utilize the very deep layers from models such as MobileNetV2, CNNs still take a great amount of time and resources. Linear discriminant analysis (LDA), a generalization of Fisher's linear discriminant, can be implemented in a multi-class classification method to increase separability of class features while not needing a high performance system to do so for image classification. Similarly, we also believe LDA has great promise in performing well. In this paper, we discuss our process of developing a robust CNN for food classification as well as our effective implementation of multi-class LDA and prove that (1) CNN is superior to LDA for image classification and (2) why LDA should not be left out of the races for image classification, particularly for binary cases.
Commentary on Postmortem diagnosis of leukodystrophies Shields LBE, Corey Handy T, Parker JC, Burns C. Postmortem diagnosis of leukodystrophies. J Forensic Sci 1998;43:1068–1071.

Commentary on Postmortem Diagnosis of Leukodystrophies Shields LBE, Corey Handy T, Parker JC, Burns C. Postmortem Diagnosis of Leukodystrophies. J Forensic Sci 1998;43:1068–1071.
Regional-Scale Pollutant Transport Studies in the Northeastern United States

There has been an effort in recent years to assess the importance to local regulatory strategies of regional-scale pollutant transport, particularly for secondary pollutants such as oxidants, nitrate, and sulfate. The U.S. Environmental Protection Agency (EPA) has established modeling and field programs to address regional-scale transport of both ambient oxidant and acidic materials.
The Pathophysiologic Role of the Bone Marrow Environment and its Niches in Multiple Myeloma

Publisher Summary The development of multiple myeloma (MM) is a complex multi-step process involving both genetic changes in the tumor cell and selective supportive conditions in the bone marrow (BM). In MM, the balanced homeostasis between these BM compartments is disrupted and supports MM cell proliferation, survival, migration, and drug resistance via activation of various signaling pathways. Despite the presence of a variety of chromosomal aberrations, translocations, and mutations in essential growth and tumor suppressor genes in MM cells, oncogenomic studies have identified few differences distinguishing MGUS from MM. This finding highlights the essential role of the BM microenvironment in disease maintenance and progression. This chapter demonstrates that direct and indirect interactions with other cells within the niches of the BM environment are key requirements for MM pathogenesis. Recent advances in biochemistry, molecular biology, and cytogenetics have markedly enhanced the knowledge of tumor cell biology within the MM BM microenvironment. Specifically, the delineation of several signaling pathways that mediate tumor cell development, growth, survival, migration, and drug resistance in the BM milieu has helped to identify and validate new targeted therapies, including bortezomib and lenalidomide. These studies will not only define mechanisms of sensitivity versus resistance to these newer agents, but also inform the design of combined therapy protocols to enhance cytotoxicity, overcome drug resistance, and improve patient outcome in MM.
Thermodynamic properties of ternary non-electrolyte solutions: Part 2. Prediction of infinite dilution activity coefficients and solubilities based on the various nibs and microscopic partition models

Abstract The limitations and applications of the various nearly ideal binary solvent (NIBS) and microscopic partition (MP) models for predicting the thermochemical properties of solutes dissolved in binary solvent mixtures are re-examined using published solute solubility and infinite dilution activity coefficient data for 48 systems. Expressions derived from the basic NIBS and extended NIBS models provide very reasonable predictions for anthracene and carbazole solubilities in systems containing both non-specific and specific interactions. For many of the systems considered, deviations between experimental values and NIBS predictions are of the order of 6% or less. In comparison, the two expressions derived from the MP model grossly overpredict the observed solubilities, with the average absolute deviations for several of the carbazole systems being 30% or more.
Parallel gastric emptying of nonhydrolyzable fat and water after a solid-liquid meal in humans.

Our aim was to examine the control of gastric emptying of the oil phase of a mixed solid and liquid meal. Previous studies had shown that liquid dietary fats normally leave the stomach at a slower rate than does water. We wished to determine whether the slower emptying of fats was due to the physical characteristics of food (lower density and greater viscosity than water), to retardation by duodenal feedback mechanisms, or whether both factors contributed. Thus, we quantified the emptying rates of water and sucrose polyester (a nonabsorbable analog of dietary fat) ingested by healthy volunteers as a mixed solid and liquid meal. Gastric emptying was quantified by an intubation-perjusion method incorporating an occlusive jejunal balloon to facilitate recovery. Four phase-specific, nonabsorbable markers were used. [14C]Sucrose octaoleate and polyethylene glycol were incorporated in the meal and traced the lipid and water phases, respectively; [3H]glycerol triether and phenolsulfonphthalein were used as duodenal recovery markers. Sucrose polyester (substituting for dietary fat) was emptied very rapidly, and at about the same rate as was water, in contrast to natural fat, which empties very slowly. Emptying of water was rapid and comparable to that observed after mixed meals containing natural fat. These results imply that gastric emptying of the oil phase is controlled by receptors sensitive to the hydrolytic products of fat digestion and that the slow emptying of dietary fat is not simply due to its lower density.
Local oestrogenic/androgenic balance in the cerebral vasculature

Reproductive effects of sex steroids are well-known; however it is increasingly apparent that these hormones have important actions on non-reproductive tissues such as the vasculature. The latter effects can be relevant throughout the lifespan, not just limited to reproductive years, and are not necessarily restricted to one gender or the other. Our work has established that cerebral blood vessels are a non-reproductive target tissue for sex steroids. We have found that oestrogen and androgens alter vascular tone, endothelial function, oxidative stress and inflammatory responses in cerebral vessels. Often the actions of oestrogen and androgens oppose each other. Moreover, it is clear that cerebral vessels are directly targeted by sex steroids, as they express specific receptors for these hormones. Interestingly, cerebral blood vessels also express enzymes that metabolize sex steroids. These findings suggest that local synthesis of 17s-estradiol and dihydrotestosterone can occur within the vessel wall. One of the enzymes present, aromatase, converts testosterone to 17s-estradiol, which would alter the local balance of androgenic and oestrogenic influences. Thus cerebral vessels are affected by circulating sex hormones as well as locally synthesized sex steroids. The presence of vascular endocrine effector mechanisms has important implications for male-female differences in cerebrovascular function and disease. Moreover, the cerebral circulation is a target for gonadal hormones as well as anabolic steroids and therapeutic drugs used to manipulate sex steroid actions. The long-term consequences of these influences are yet to be determined.
Are locus of control and depression related

39 inpatients at a private psychiatric hospital were administered the Rotter Locus of Control Scales and the MMPI. External locus of control was compared for groups using multiple definitions of depression. Generally, comparisons did not support the hypothesis that depressed individuals are more external and the direction of the scores suggests the results of any given study may depend on the type of depressed individuals in the samples. The above results, the correlations between locus of control and the MMPI scales, and a review of the literature suggest types or degree of depression may have different dynamics and some types may be related to locus of control while other types of depression are not related to locus of control.
On the equations of motion for rigid bodies with surface growth

Appropriate balance equations are formulated for a body whose geometry, mass and inertia vary due to surface growth. The distance between any two particles of the body is assumed to be fixed and hence several interesting simplifications of the balance laws occur. In particular, a set of ordinary differential equations for the attitude and position of the body are developed. The dynamics predicted by these equations for a body moving on an incline, and gathering mass as it does so, are discussed.
SU-GG-T-225: Correction for Directional Response of a 2D Ion Chamber Array for Quality Assurance of Arc Radiotherapy and IMRT

Purpose: To characterize the directional response of a 2D ion chamber array (PTW Seven29) and implement techniques for its use in dose verification of arc and IMRTradiotherapy.Method and Materials: The directional response of the 27×27 ion chamber array was measured for 10cm, 7cm and 4cm square fields irradiated at a range of gantry angles from 0° to 180° relative to the vertical. For verification of IMRT or arc plans, two methods are proposed for using the Seven29 in combination with rectangular slabs of solid water. The first method requires adding an attenuation shell to the solid water in the treatment planning system (TPS) to compensate for the Seven29 directional response. The second method employs two Seven29 measurements with opposing orientations of the measuring device. The measured dose is estimated to be 0.53*[ Dose up (i,j)+ Dose down (j,i)] where the subscripts indicate the orientation of the Seven29 and i, j are indices of the ion chamber array. These methods were tested on an arc plan with a 5×5 cm2field size.Results: Measurements of the Seven29 indicate a relatively flat response for gantry angles from 180° to 150° decreasing to about 97% at 135°. Posterior beams show a uniformly flat response of 89% across a range of beam angles. The directional response was found to be independent of the field size. Measured dose profiles of the arc plan were found to be 3.8% lower than the calculated dose without correction. Using method one, the agreement was within 1.4%. For method two, corrected chamber readings were within 1% of the TPS values. Conclusion: The Seven29 is a valuable tool for verification of arc and IMRTtreatments. Through the characterization of its directional response, accurate 2D maps can be generated for quality assurance of the radiation delivery of complex IMRT or arc plans.
Innovative sharing: Shared accounting information as a facilitator of trust and performance ☆

Abstract Creating and maintaining competitive advantage requires firms to foster strategies that encourage and support employees’ efforts. In this paper, I report on a large U.S. firm's innovation to share accounting information with employees. Based on data from 258 employees, I report that shared accounting information impacts workers’ trust in management and performance.
A new statistical approach for the analysis of uncertain systems

This paper addresses the issues of conservativeness and computational complexity of probabilistic robustness analysis. The authors solve both issues by defining a new sampling strategy and robustness measure. The new measure is shown to be much less conservative than the existing one. The new sampling strategy enables the definition of efficient hierarchical sample reuse algorithms that reduce significantly the computational complexity and make it independent of the dimension of the uncertainty space. Moreover, the authors show that there exists a one to one correspondence between the new and the existing robustness measures and provide a computationally simple algorithm to derive one from the other.
Terrestrial ecosystems and the carbon cycle

The terrestrial biosphere plays an important role in the global carbon cycle. In the 1994 Intergovernmental Panel Assessment on Climate Change (IPCC), an effort was made to improve the quantification of terrestrial exchanges and potential feedbacks from climate, changing CO2, and other factors; this paper presents the key results from that assessment, together with expanded discussion. The carbon cycle is the fluxes of carbon among four main reservoirs: fossil carbon, the atmosphere, the oceans, and the terrestrial biosphere. Emissions of fossil carbon during the 1980s averaged 5.5 Gt y−1. During the same period, the atmosphere gained 3.2 Gt C y−1 and the oceans are believed to have absorbed 2.0 Gt C y−1. The regrowing forests of the Northern Hemisphere may have absorbed 0.5 Gt C y−1 during this period. Meanwhile, tropical deforestation is thought to have released an average 1.6 Gt C y−1 over the 1980s. While the fluxes among the four pools should balance, the average 198Ds values lead to a ‘missing sink’ of 1.4 Gt C y−1 Several processes, including forest regrowth, CO2 fertilization of plant growth (c. 1.0 Gt C y−1), N deposition (c. 0.6 Gt C y−1), and their interactions, may account for the budget imbalance. However, it remains difficult to quantify the influences of these separate but interactive processes. Uncertainties in the individual numbers are large, and are themselves poorly quantified. This paper presents detail beyond the IPCC assessment on procedures used to approximate the flux uncertainties. Lack of knowledge about positive and negative feedbacks from the biosphere is a major limiting factor to credible simulations of future atmospheric CO2 concentrations. Analyses of the atmospheric gradients of CO2 and 13 CO2 concentrations provide increasingly strong evidence for terrestrial sinks, potentially distributed between Northern Hemisphere and tropical regions, but conclusive detection in direct biomass and soil measurements remains elusive. Current regional-to-global terrestrial ecosystem models with coupled carbon and nitrogen cycles represent the effects of CO2 fertilization differently, but all suggest longterm responses to CO2 that are substantially smaller than potential leaf- or laboratory whole plant-level responses. Analyses of emissions and biogeochemical fluxes consistent with eventual stabilization of atmospheric CO2 concentrations are sensitive to the way in which biospheric feedbacks are modeled by c. 15%. Decisions about land use can have effects of 100s of Gt C over the next few centuries, with similarly significant effects on the atmosphere. Critical areas for future research are continued measurements and analyses of atmospheric data (CO2 and 13CO2) to serve as large-scale constraints, process studies of the scaling from the photosynthetic response to CO2 to whole-ecosystem carbon storage, and rigorous quantification of the effects of changing land use on carbon storage.
A variational free‐Lagrange method for shallow water

The variational approach The derivation and analysis of conservative numerical methods for global climate modeling is a challenging and active area of research. The traditional ap proach to deriving such methods requires the numerical analyst to exercise some level of their own bias. To remedy this and systematically derive the numerical method from a conferred mathematical understanding, Salmon (1) pursues the variational approachfor geophysical modeling. The power of the variational approach rests upon Noether’s theorem which states that eac h continuous symmetry of Hamilton’s action principle exhib its a corresponding conservation law. Consequently, the numerical analyst need only choose a suitable discretisation of Hamilton’s action principle, with the confidence that not only will the r esulting semi-discrete equations of motion preserve geometric structure, manifesting in energy conservation, but that th ese equations will conserve additional quantities corresp onding to the symmetries of the discrete action principle. Voronoi diagram Following (2), we firstly outline a variational free-Lagran ge (VFL) method for rotating shallow water. A distinguishing feature of the free-Lagrange method is the use of a Voronoi diagram to represent the layer thickness. The Voronoi diagram is attractive from both a practical and theoretical perspective. Firstly the approach is completely fr ee from mesh-tangling problems (see 3) which compromise the performance of many of the mesh-based Lagrangian methods. Additionally, (4) shows that the corresponding discrete Hamilton’s action principle permits translational and rotationa l symmetries and hence respective linear and angular momentum conservation laws. Symplectic integrator Our contribution is to exploit the symplectic structure pre served by the VFL method by using a symplectic time-stepper (see 5, for a review of symplectic methods for particle methods). We demonstrate by numerical experiment that the combination of the VFL method with an explicit symplectic time-stepper exhibits no secular drift in the energy error. This property together with the computational tractability renders this approach suitable for long- time geophysical simulations.
Development of softcopy environment for primary color banding visibility assessment

Fine-pitch banding is one of the most unwanted artifacts in laser electrophotographic (EP) printers. It is perceived as a quasiperiodic fluctuation in the process direction. Therefore, it is essential for printer vendors to know how banding is perceived by humans in order to improve print quality. Monochrome banding has been analyzed and assessed by many researchers; but there is no literature that deals with the banding of color laser printers as measured from actual prints. The study of color banding is complicated by the fact that the color banding signal is physically defined in a three-dimensional color space, while banding perception is described in a one-dimensional sense such as more banding or less banding. In addition, the color banding signal arises from the independent contributions of the four primary colorant banding signals. It is not known how these four distinct signals combine to give rise to the perception of color banding. In this paper, we develop a methodology to assess the banding visibility of the primary colorant cyan based on human visual perception. This is our first step toward studying the more general problem of color banding in combinations of two or more colorants. According to our method, we print and scan the cyan test patch, and extract the banding profile as a one dimensional signal so that we can freely adjust the intensity of banding. Thereafter, by exploiting the pulse width modulation capability of the laser printer, the extracted banding profile is used to modulate a pattern consisting of periodic lines oriented in the process direction, to generate extrinsic banding. This avoids the effect of the halftoning algorithm on the banding. Furthermore, to conduct various banding assessments more efficiently, we also develop a softcopy environment that emulates a hardcopy image on a calibrated monitor, which requires highly accurate device calibration throughout the whole system. To achieve the same color appearance as the hardcopy, we perform haploscopic matching experiments that allow each eye to independently adapt to different viewing conditions; and we find an appearance mapping function in the adapted XYZ space. Finally, to validate the accuracy of the softcopy environment, we conduct a banding matching experiment at three different banding levels by the memory matching method, and confirm that our softcopy environment produces the same banding perception as the hardcopy. In addition, we perform two more separate psychophysical experiments to measure the differential threshold of the intrinsic banding in both the hardcopy and softcopy environments, and confirm that the two thresholds are statistically identical. The results show that with our target printer, human subjects can see a just noticeable difference with a 9% reduction in the banding magnitude for the cyan colorant.
Update on Uranium Availability; Current and Forecast Mine Production and the Resources Issue

During the past three years, uranium price followed a very fast rise, and this trend is continuing. What does it mean? Short term or long term tension, speculation, resources depletion signal?Because for many, “what is expensive is necessarily scarce”, updating our knowledge on the uranium market situation, likely future trend and prospects is essential.Fast economic growth in Asia, population increase, global warming issues are the main drivers of an already perceivable nuclear renaissance. The uranium resources availability is a key factor to define the future share of nuclear power, the reactor technology and the related fuel cycle.Three periods of time are identified and are requesting specific answers:- Near term; a period when nuclear power must show its ability to reliably address global power needs and global warming concerns- Long term; a period when nuclear power will ramp-up well beyond current capacity using mainly proven advanced LWR technology (Gen 3+)- Very long term; a period yet to be defined when nuclear power will ramp-up to very high capacity using a mix including a significant share of advanced Gen 4 reactors.After a detailed analysis of current supplies and today’s price signal interpretation, the content of this paper is aimed at addressing the following basic questions:- Near term uranium supply issues?- Uranium production ramp-up capability?- Long term Uranium Resources availability?To conclude, a discussion about future Nuclear Fuel security of supply according to various scenarios for the global nuclear power plant fleet will tentatively describe the uranium supply scene for the long run and show its adequacy.
A distribution-free approach to estimating best response values with application to mutual fund performance modeling

Frontier regression models seek to model and estimate best rather than average values of a response variable. Our proposed frontier model has similar intent, but also allows for an additional error term. The composed error approach uses the sum of two error terms, one an inefficiency error and the other as white noise. Previous research proposed assumptions on the distributions of the error components so that the distribution of this total error can be specified. Here we propose a distribution free approach to specifying these errors. In addition, our approach is completely data driven, rendering model specification an unnecessary step. We also outline, step-by-step, an approach to implementing this procedure. Our entire approach is illustrated with a mutual fund data set from the Morning Star database.
Mechanical and morphological variation of the human lumbar vertebral cortical and trabecular bone.

The nanoindentation technique was used to characterize the variation in the elastic modulus and hardness of human lumbar vertebral cortical and trabecular bone. The elastic modulus (and in most cases, the hardness as well) of axially aligned trabeculae cut in the transverse direction was significantly greater than in other orientations of vertebral cortical and trabecular bone. In all cases, the elastic modulus and hardness of bone in the load-bearing direction was greater than in corresponding bone types cut in the other directions. Scanning electron micrographs of cortical shell revealed the Haversian-like canal systems expected in secondary cortical bone, but it was difficult to differentiate by morphology cortical from trabecular bone in the human lumbar vertebrae.
SU-GG-J-193: Using Small-Deformation Linear-Elastic Registration to Quantifying Ventilation-Competent Lung Imaging From Clinical 4DCT Datasets: Toward Selective Avoidance IMRT for Locally Advanced Non-Small-Cell Lung Cancer

Purpose: To verify the feasibility of a small‐deformation inverse‐consistent linear‐elastic (SICLE) registration algorithm in quantifying ventilation‐competent sublung images from 4D CT datasets. Materials/Method: SICLE, a deformable image registration algorithm developed at the University of Iowa, was utilized to register the 100% inhalation and 100% exhalation phases of the lung which were extracted from clinical 4D CT datasets. The SICLE method performs inverse consistent image registration in which the forward and reverse transformations are estimated jointly while minimizing the inverse consistency error. After deformable registration, ventilation was calculated using the equation Δ V/Vex = 1000 ( HUin − HUex )/( HUex (1000 + HUin )) on voxels of the inhalation and exhalation images, where HU is in Hounsfield Units and ΔV/Vex is the change in regional volume divided by the local volume. Results: SICLE was found to be efficient and consistent in deformable image registering lungCTimage datasets with different phases. 3D ventilation images were quantified and given in coronal, transverse, and sagittal view. Quantitative ventilation in a given region of interest was also determined. Ventilation‐competent sublung regions were constructed with different functionality levels of 90, 70, 50, and 30%. Conclusion: Utilizing a small‐deformation inverse‐consistent linear‐elastic registration algorithm, it was feasible to quantify ventilation competent subregions from clinical 4D CT datasets. Given the availability of 4D CT technology, this study opens a pathway to integrate functional lunginformation into radiotherapy for locally advanced non‐small‐cell lungcancer.
On the Definition and Approximation of Feynman's Path Integrals

A general and compact expression for Feynman's path integral has been obtained. A classical method is given for the computation of such expressions. The example of a Dirac particle in a constant external electromagnetic field is treated by this method.
New bulk sulfur measurements of Martian meteorites and modeling the fate of sulfur during melting and crystallization – Implications for sulfur transfer from Martian mantle to crust–atmosphere system

Abstract Sulfur storage and transport between different reservoirs such as core, mantle, crust and atmosphere of Mars are tied to igneous processes. Martian meteorites carry a record of mantle melting and subsequent differentiation history of Martian magmas. Investigation of S geochemistry of Martian meteorites can thus provide an understanding of how S is transferred from the Martian interior to the exosphere. In this study we measured bulk S concentration of 7 Martian meteorites and modeled the behavior of S during both isobaric crystallization of primary Martian magmas and isentropic partial melting of Martian mantle. Comparisons between measured data and modeled results suggest that (1) sulfides may become exhausted at the source during decompression melting of the mantle and mantle-derived basalts may only become sulfide-saturated after cooling and crystallization at shallow depths and (2) in addition to degassing induced S loss, mixing between these differentiated sulfide-saturated basaltic melts and cumulus minerals with/without cumulate sulfides could also be responsible for the bulk sulfur contents in some Martian meteorites. In this case, a significant quantity of S could remain in Martian crust as cumulate sulfides or in trapped interstitial liquid varying from 2 to 95 percent by weight. Our modeling also suggests that generation of sulfide-undersaturated parental magmas requires that the mantle source of Martian meteorites contain
On the effect of an applied magnetic field on sound adsorption in oxygen

Abstract The adsorption of sound in oxygen in a magnetic field up to 11.6 kgauss and at pressures down to 0.1 atmosphere was measured using an acoustic interferometer. No anomalous effects were observed, in contradiction to previous observations.
Elastic Stability of an Externally Pressurized Ring with Two Hinges

A thin ring or cylinder with two hinges is buckled by external pressure. The buckling pressure is determined as a function or spacing between the hinges. In certain instances two hinges may be more stable than a single hinge. Optimum spacing is one quarter of the perimeter where the buckling pressure is as high as the ring without hinges. Ein dunner Ring oder Zylinder wird durch auseren Druck geknickt. Der Knickdruck wird als eine Funktion oder in Abhangigkeit vom Abstand zwischen den Gelenken bestimmt. In bestimmten Beispielen sind zwei Gelenke stabiler als ein einziges. Der optimale Abstand ist ein Viertel des Umfangs, bei dem der Knickdruck so hoch ist wie beim Ring ohne Gelenke.
Stimulus intensity, catch trial effects, and the speed-accuracy tradeoff in reaction time: A variable criterion theory interptation

Ss responded to a 1,000-Hz tone of 50, 80, or 100 dB. Catch trial conditions were none, blank trials, a red light, a noise, and an 1,800-Hz tone. Auditory catch signals were of the same intensities. RT distributions in the first three conditions were well described by a family of exponential growth functions dependent upon stimulus intensity and by the parameters of normal criterion distributions dependent upon catch trial conditions and between-session variability. Performance in the auditory catch trial conditions was not dependent upon the same set of sensory growth functions. Performance in these conditions was described by a two-dimensional analysis of information transmitted as a function of time and interpreted in terms of variable criterion theory. The speed-accuracy tradeoff in this situation appears to depend upon differential rates of growth of intensity and associative information and the criterion used in responding to this information.
Skeletal Unloading Causes Resistance of Osteoprogenitor Cells to Parathyroid Hormone and to Insulin-like Growth Factor-I

Skeletal unloading decreases bone formation and osteoblast number in vivo and decreases the number and proliferation of bone marrow osteoprogenitor (BMOp) cells in vitro. We tested the ability of parathyroid hormone (PTH) to stimulate BMOp cells in vivo by treating Sprague Dawley rats (n = 32) with intermittent PTH(1-34) (1 h/day at 8 microg/100 g of body weight), or with vehicle via osmotic minipumps during 7 days of normal weight bearing or hind limb unloading. Marrow cells were flushed from the femur and cultured at the same initial density for up to 21 days. PTH treatment of normally loaded rats caused a 2.5-fold increase in the number of BMOp cells, with similar increases in alkaline phosphatase (ALP) activity and mineralization, compared with cultures from vehicle-treated rats. PTH treatment of hind limb unloaded rats failed to stimulate BMOp cell number, ALP activity, or mineralization. Hind limb unloading had no significant effect on PTH receptor mRNA or protein levels in the tibia. Direct in vitro PTH challenge of BMOp cells isolated from normally loaded bone failed to stimulate their proliferation and inhibited their differentiation, suggesting that the in vivo anabolic effect of intermittent PTH on BMOp cells was mediated indirectly by a PTH-induced factor. We hypothesize that this factor is insulin-like growth factor-I (IGF-I), which stimulated the in vitro proliferation and differentiation of BMOp cells isolated from normally loaded bone, but not from unloaded bone. These results suggest that IGF-I mediates the ability of PTH to stimulate BMOp cell proliferation in normally loaded bone, and that BMOp cells in unloaded bone are resistant to the anabolic effect of intermittent PTH therapy due to their resistance to IGF-I.
Ultrastructural analysis of somatostatin-immunoreactive neurons and synapses in the temporal and occipital cortex of the macaque monkey.

Somatostatin-containing neurons and terminals have been analyzed in monkey temporal and occipital cortex by using light and electron microscopic immunohistochemistry. An antibody against Somatostatin-28(1–12), that was shown previously preferentially to label fibers (Morrison et al.: Brain Research 262:344–351, 1983), was utilized. As expected, few cell bodies were labeled. At the electron microscopic level, labeled cells presented a characteristic asymmetric position of the nucleus and very few symmetric or asymmetric synapses on the somatic surface. In all areas examined, somatostatin fibers formed a dense plexus in the most superficial layers (I-upper III). The density of labeled fibers in intermediate (deep III–IV) and deep layers (V–VI) varied considerably among areas. The synaptic relationships of the immunoreactive fibers were analyzed and postsynaptic targets quantified in V1, V2, and the superior and inferior temporal gyrus (STG and ITG, respectively). The synapses formed by somatostatin-labeled boutons were of the symmetric type (type II) and the primary postsynaptic targets were dendritic shafts. No regional differences were found in the distribution of the postsynaptic targets in layers I-upper III. The pattern of synapses in the deep layers was examined in STG. The frequency and distribution of postsynaptic targets was similar to the superficial layers of STG and the other temporal and occipital regions. In intermediate layers of the temporal cortex areas there was an increase in the proportion of synapses on dendritic spines. In a correlated light and electron microscopic analysis we examined synapses made by radial fibers in these regions and found that although the main targets are distal dendritic shafts, almost 40% of synapses were on dendritic spines. We suggest that the radial fibers may originate from a specialized interneuron, previously described as the double bouquet cell, and that this particular subset of somatostatin-containing double bouquet cells is likely to exhibit a very high degree of regional heterogeneity with a preference for association cortices with extensive cortico-cortical convergence.