cssi/SciSciGPT-SciSciNet huggingface dataset:
Collaborative sparse priors for multi-view ATR

Recent work has seen a surge of sparse representation based classification (SRC) methods applied to automatic target recognition problems. While traditional SRC approaches used l0 or l1 norm to quantify sparsity, spike and slab priors have established themselves as the gold standard for providing general tunable sparse structures on vectors. In this work, we employ collaborative spike and slab priors that can be applied to matrices to encourage sparsity for the problem of multi-view ATR. That is, target images captured from multiple views are expanded in terms of a training dictionary multiplied with a coefficient matrix. Ideally, for a test image set comprising of multiple views of a target, coefficients corresponding to its identifying class are expected to be active, while others should be zero, i.e. the coefficient matrix is naturally sparse. We develop a new approach to solve the optimization problem that estimates the sparse coefficient matrix jointly with the sparsity inducing parameters in the collaborative prior. ATR problems are investigated on the mid-wave infrared (MWIR) database made available by the US Army Night Vision and Electronic Sensors Directorate, which has a rich collection of views. Experimental results show that the proposed joint prior and coefficient estimation method (JPCEM) can: 1.) enable improved accuracy when multiple views vs. a single one are invoked, and 2.) outperform state of the art alternatives particularly when training imagery is limited.
Effects of Bubbles on the Hydraulic Conductivity of Porous Materials – Theoretical Results

In a porous material, both the pressure drop across a bubble and its speed are nonlinear functions of the fluid velocity. Nonlinear dynamics of bubbles in turn affect the macroscopic hydraulic conductivity, and thus the fluid velocity. We treat a porous medium as a network of tubes and combine critical path analysis with pore-scale results to predict the effects of bubble dynamics on the macroscopic hydraulic conductivity and bubble density. Critical path analysis uses percolation theory to find the dominant (approximately) one-dimensional flow paths. We find that in steady state, along percolating pathways, bubble density decreases with increasing fluid velocity, and bubble density is thus smallest in the smallest (critical) tubes. We find that the hydraulic conductivity increases monotonically with increasing capillary number up to Ca ∼ 10−2, but may decrease for larger capillary numbers due to the relative decrease of bubble density in the critical pores. We also identify processes that can provide a positive feedback between bubble density and fluid flow along the critical paths. The feedback amplifies statistical fluctuations in the density of bubbles, producing fluctuations in the hydraulic conductivity.
Homology Bases Arising from Reductive Groups Over a Finite Field

Let G be a connected reductive algebraic group over k, an algebraic closure of a finite field F q with q elements. Assume that we are given an F q -rational structure on G with Frobenius map F: G → G. Let \(\bar{\mathbb{Q}}{{}_{l}}\) be an algebraic closure of the l-adic numbers (l is a fixed prime number, invertible in F q ).
Digital mapping of a soil profile

SUMMARY: Detailed information on soil profiles is required for site characterization, soil mapping, studies on pedogenesis, soil–landscape modelling and soil classification. In this study, we used digital soil mapping techniques to map the profile wall of an Alfisol (90‐cm depth × 100‐cm width). Geochemical data (sampled at 10 cm × 10 cm) and digital images (resolution 1 cm × 1 cm) were used as input data in models that predicted a range of properties across the soil profile. Fuzzy c‐means clustering was applied to the profile and colour maps, and a confusion index was calculated. The colour coordinates were strongly correlated with SOC (soil organic carbon), sand and silt contents, and weathering indices. Random forest using the RGB model (R² = 0.57, RMSE (root mean square error) = 2.41) showed less accurate prediction of SOC content than random forest using the CIE L*a*b* (R² = 0.84, RMSE = 1.57) and HSV, hue, saturation, chroma (R² = 0.85, RMSE = 1.46) models. Detailed profile maps showed considerable within‐horizon variation and identified animal holes, roots and limestone fragments. Colour and profile maps of soil properties and weathering indices matched field‐delineated soil horizons. Clusters obtained by soil properties and weathering indices represented the field‐delineated horizons and had the largest overall accuracy (P = 0.85 and 0.86, respectively). The confusion index showed that the horizons had wavy and somewhat irregular boundaries. We conclude that colour coordinates are useful for predicting and mapping soil properties in soil profiles. Random forest can be used to produce high‐resolution soil profile maps, and fuzzy c‐means clustering is useful for delineating soil horizons. HIGHLIGHTS: We investigated the use of digital images in soil horizon delineation and within soil horizon variation We used various colour models to map soil profile properties and define horizons Colour and profile maps of soil properties and weathering indices matched field delineated soil horizons. Random forest can produce high‐resolution soil profile maps, and fuzzy c‐means clustering can delineate soil horizons
Periodically Switched Communication Topology in Multi-agent Consensus Control: Stability and Floquet Theory

The goal of this paper is to investigate stability of consensus control of linear multi-agent systems with periodically switched communication topologies. To this end, our contribution is to exploit Floquet theory as a main tool to investigate the stability of consensus problem for a switched system that consists of a set of linear time invariant subsystems and a periodic switching rule. The Lyapunov stability analysis for discrete-time systems is also discussed to confirm the results of utilizing Floquet theory. The simulation results are illustrated for the cases with single-integrator dynamics, double-integrator dynamics and leader-follower consensus problem.
Distributed Reduced Order Source Identification

In this paper we propose a distributed approach for model-based Source Identification (SI) that minimizes communication cost and allows for on demand balancing of computational resources, based on the specifications of the sensors. Specifically, we consider the steady-state Advection-Diffusion equation which we discretize using the Finite Element (FE) method, and then apply Proper Orthogonal Decomposition to reduce the order of the model. The concentration measurements that are needed to solve the SI problem are collected by a team of mobile sensors that move in pre-assigned subdomains in the environment. We formulate an $\ell_{2}$ -regularized least squares optimization problem that the sensors solve in a distributed way using the Accelerated Distributed Augmented Lagrangian method. Our formulation results in an algorithm whose communication cost is independent of the FE mesh size and its time complexity grows only linearly with it. We present simulation results that show that the proposed method can handle large-scale SI problems and compare our formulation to an alternative derivation using Alternating Direction Method of Multipliers.
Emerging Adulthood Measured at Multiple Institutions 2: The Data

Collaborators from 32 academic institutions primarily in the United States collected data from emerging adults (Nraw = 4220, Nprocessed = 3134). Participants completed self-report measures assessing markers of adulthood, IDEA inventory of dimensions of emerging adulthood, subjective well-being, mindfulness, belonging, self-efficacy, disability identity, somatic health, perceived stress, perceived social support, social media use, political affiliation, beliefs about the American dream, interpersonal transgressions, narcissism, interpersonal exploitativeness, beliefs about marriage, and demographics. The data are available at ( https://osf.io/qtqpb/ ) with details about the study and contributors at our main EAMMi2 page ( https://osf.io/te54b/ ). These data may be used to examine new research questions, provide authentic research experiences for students, and provide demonstrations for research and statistics courses.
David Oliver: Top healthcare words of 2018.

The Collins English Dictionary ’s top 10 words of 20181 included “plogging” (picking up litter while jogging), “VAR” (video assistant referee), and “floss” (a new dance craze). So, as The BMJ heads to the New Year, here’s my personal list of the top words of 2018 for UK health services. I’ve doubtless missed some, so please do post rapid responses or tweet your own suggestions. It’s been good to see, for the first time in the NHS’s history, a draft workforce plan (technically, a “strategy”)—from Health Education England.2 It has its imperfections, but at least it’s a plan. And we’re eagerly expecting the launch of NHS England’s 10 year plan for the health service.3 Again, not everyone will be happy with its details, but a shift towards medium term plans beats short term, politically driven cycles. It’s a start. To my mind,4 and …
Construction of optimal run order in design of experiments

It is sometimes favorable to conduct experiments in a systematic run order rather than the conventional random run order. In this article, we propose an algorithm to construct the optimal run order. The algorithm is very flexible: it is applicable to an..
Improving Human-Machine Collaboration Through Transparency-based Feedback – Part I: Human Trust and Workload Model

Abstract In this paper, we establish a partially observable Markov decision process (POMDP) model framework that captures dynamic changes in human trust and workload for contexts that involve interactions between humans and intelligent decision-aid systems. We use a reconnaissance mission study to elicit a dynamic change in human trust and workload with respect to the system’s reliability and user interface transparency as well as the presence or absence of danger. We use human subject data to estimate transition and observation probabilities of the POMDP model and analyze the trust-workload behavior of humans. Our results indicate that higher transparency is more likely to increase human trust when the existing trust is low but also is more likely to decrease trust when it is already high. Furthermore, we show that by using high transparency, the workload of the human is always likely to increase. In our companion paper, we use this estimated model to develop an optimal control policy that varies system transparency to affect human trust-workload behavior towards improving human-machine collaboration.
Shining the Light on Mental Health in a Population at Risk: Cerebral Palsy and Other Developmental Disabilities.

The editorialists discuss the importance of Whitney and colleagues' findings to patients, health professionals, policymakers, and researchers.
The use of poetry therapy in sex therapy

Poetry therapy has been shown to have benefits with many types of clients with many presenting issues. The goals and mechanics of poetry therapy lend well to the integration of poetry therapy into ...
Chromatic refraction in the lower atmosphere associated with refractive index gradient features

The performance of certain free space optical applications such as laser communication, LIDAR, target designation and astronomical observations may be improved by using beams of different wavelengths for the auxiliary actions of pointing/tracking or turbulence correction. Thus, wavelength dispersion in the atmosphere is a topic of concern for such applications. The chromatic effects of refraction in the atmosphere are generally well-understood and are a function of temperature, pressure, humidity and altitude, as well as the refractive index gradients. In applications such as astronomical observations, chromatic effects are typically predicted based on standard atmospheric models. However, for long horizontal or near-horizontal paths near the Earth’s surface, significant refractive index gradients can be encountered that are associated with features such as inverse temperature layers and ducts. In this study, we explore the wavelength dependence of optical propagation through these temporary and reoccurring refractive index profiles. A ray tracing approach is implemented and the chromatic divergence of the rays through an inverse temperature layer is studied and compared with the behavior expected for the standard atmosphere.
Quantitative Variable Autonomy Levels for Traded Control in a Pick-and-Place Task

As robotic agents become increasingly present in human environments, task completion rates during human-robot interaction is an important topic of research. Safe collaborative robots executing tasks under human supervision often augment their perception and planning capabilities through traded or shared control schemes. In this paper, we present a quantitatively defined model for sliding-scale autonomy, in which levels of autonomy are determined by the relative efficacy of autonomous subroutines. We experimentally test the resulting Variable Autonomy Planning (VAP) algorithm against a traditional traded control scheme in a pick-and-place task. Results show that prioritizing autonomy levels with higher success rates as encoded into VAP, allows users to effectively and intuitively select optimal autonomy levels for efficient task completion.
Statutory delegation, agency authority, and the asymmetry of impact analysis

Requirements for regulatory impact analysis in the United States vary greatly. Executive branch regulatory agencies in the United States are required to conduct regulatory impact analysis before is...
Construction of Acylindrical Hyperbolic 3-Manifolds with Quasifuchsian Boundary

We construct a one (real) dimensional deformation of an acylindrical hyperbolic 3-manifold, compute some associated arithmetic invariants and exhibit the skinning map along the deformation locus. T...
Poverty and the Savage Slot.

In today’s anthropology, the word “culture” is conspicuous by its absence from anthropological discourse. But the word is still alive outside anthropology, particularly in sociology and psychology,...
Complications following symptom-limited thoracentesis using suction

Background Thoracentesis using suction is perceived to have increased risk of complications including pneumothorax and re-expansion pulmonary edema (REPE). Current guidelines recommend limiting drainage to 1.5 L to avoid REPE. Our purpose was to examine the incidence of complications with symptom limited drainage of pleural fluid using suction and identify risk factors for REPE. Methods A retrospective cohort study of all adult patients who underwent symptom limited thoracentesis using suction at our institution between 1/1/2004 and 8/31/2018 was performed, and a total of 10 344 thoracenteses were included. Results Pleural fluid ≥1.5 L was removed in 19% of the procedures. Thoracentesis was stopped due to chest discomfort (39%), complete drainage of fluid (37%), and persistent cough (13%). Pneumothorax based on chest radiograph was detected in 3.98%, but only 0.28% required intervention. The incidence of REPE was 0.08%. The incidence of REPE increased with Eastern Cooperative Oncology Group performance status (ECOG) ≥3 compounded with ≥1.5 L (0.04 to 0.54%, 95% CI 0.13–2.06). Thoracentesis in those with ipsilateral mediastinal shift did not increase complications, but less fluid was removed (p Conclusions Symptom limited thoracentesis using suction is safe even with large volumes. Pneumothorax requiring intervention and REPE are both rare. There were no increased procedural complications in those with ipsilateral mediastinal shift. REPE increased with poor performance status and drainage ≥1.5 L. Symptom limited drainage using suction without pleural manometry is safe.
Tulsa 1921: Reporting a Massacre: Krehbiel, Randy. Norman, OK: University of Oklahoma Press, 2019, 309 pp., $29.95 (hardcover).

The racial violence that erupted in Tulsa, Oklahoma, on May 31, 1921, was a catastrophe for the city’s African American citizens. Armed whites invaded the city’s Greenwood District, a thriving area...
An experimental analysis of the extinction‐induced response burst

The occurrence, time course, and repeatability of response rate increases following the onset of extinction, the extinction burst, were studied in three experiments. Nine pigeons were exposed to at least 5 cycles of 5-session blocks of conditioning followed by 8-session blocks of extinction. In different experiments, conditioning sessions either were a fixed-ratio (FR) or variable-ratio (VR) schedule, and transitions from the last conditioning session in each cycle to the first extinction session were conducted between or within sessions. A single response rate increase occurred when overall response rates were considered. Restricting analyses to the first minute of extinction sessions sometimes revealed increases in response rates, although this finding was inconsistent. The frequency and magnitude of these increases differed across exposures to extinction both across and within pigeons. Additionally, how responding during extinction was measured (i.e., the level of analysis) influenced whether increases above baseline levels were observed. These results suggest that the extinction burst may be influenced by the manner of transition to extinction and the way in which early extinction responding is measured. Under the best conditions, the extinction burst does not appear to be a ubiquitous effect of extinction.
Executive Decision-Making: Linking Dynamic Managerial Capabilities to the Resource Portfolio and Strategic Outcomes

To more completely understand the basis for firm performance differences, we need greater clarity on the drivers of differentiation in managerial strategic decision-making, as well as on the impact these decisions have on the composition and configuration of the firm’s resource portfolio. In this paper, we provide an integrative framework that illustrates how strategic leaders influence firm strategy and performance. Our model clarifies the role that dynamic managerial capabilities play in fashioning a unique bundle of resources for the firm, thus leading to differences in firm strategies and performance outcomes. The process is illustrated by examples drawn from industry.
Plasma metabolomic profiling in patients with rheumatoid arthritis identifies biochemical features predictive of quantitative disease activity.

BACKGROUND Rheumatoid arthritis (RA) is a chronic, autoimmune disorder characterized by joint inflammation and pain. In patients with RA, metabolomic approaches, i.e., high-throughput profiling of small-molecule metabolites, on plasma or serum has thus far enabled the discovery of biomarkers for clinical subgroups, risk factors, and predictors of treatment response. Despite these recent advancements, the identification of blood metabolites that reflect quantitative disease activity remains an important challenge in precision medicine for RA. Herein, we use global plasma metabolomic profiling analyses to detect metabolites associated with, and predictive of, quantitative disease activity in patients with RA. METHODS Ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was performed on a discovery cohort consisting of 128 plasma samples from 64 RA patients and on a validation cohort of 12 samples from 12 patients. The resulting metabolomic profiles were analyzed with two different strategies to find metabolites associated with RA disease activity defined by the Disease Activity Score-28 using C-reactive protein (DAS28-CRP). More specifically, mixed-effects regression models were used to identify metabolites differentially abundant between two disease activity groups ("lower", DAS28-CRP ≤ 3.2; and "higher", DAS28-CRP > 3.2) and to identify metabolites significantly associated with DAS28-CRP scores. A generalized linear model (GLM) was then constructed for estimating DAS28-CRP using plasma metabolite abundances. Finally, for associating metabolites with CRP (an indicator of inflammation), metabolites differentially abundant between two patient groups ("low-CRP", CRP ≤ 3.0 mg/L; "high-CRP", CRP > 3.0 mg/L) were investigated. RESULTS We identified 33 metabolites differentially abundant between the lower and higher disease activity groups (P < 0.05). Additionally, we identified 51 metabolites associated with DAS28-CRP (P < 0.05). A GLM based upon these 51 metabolites resulted in higher prediction accuracy (mean absolute error [MAE] ± SD: 1.51 ± 1.77) compared to a GLM without feature selection (MAE ± SD: 2.02 ± 2.21). The predictive value of this feature set was further demonstrated on a validation cohort of twelve plasma samples, wherein we observed a stronger correlation between predicted and actual DAS28-CRP (with feature selection: Spearman's ρ = 0.69, 95% CI: [0.18, 0.90]; without feature selection: Spearman's ρ = 0.18, 95% CI: [-0.44, 0.68]). Lastly, among all identified metabolites, the abundances of eight were significantly associated with the CRP patient groups while controlling for potential confounders (P < 0.05). CONCLUSIONS We demonstrate for the first time the prediction of quantitative disease activity in RA using plasma metabolomes. The metabolites identified herein provide insight into circulating pro-/anti-inflammatory metabolic signatures that reflect disease activity and inflammatory status in RA patients.
Application and Development of Carbon Nanotubes in Manufacturing

Decades after the concept of carbon nanotubes was proposed and became a hot topic of research, there is a new focus on the application of such materials with excellent chemical and physical properties in manufacturing. After investigating academic reports on nanoscale manufacturing in the past few years, this paper discusses and summarizes various potential applications of carbon nanotubes, both electrical and non-electrical. Moreover, with the increasing computer computing power and the improvement of machine learning algorithms, study of CNT based on AI becomes a new and effective way to learn more about this material. However, there are still some unknown properties of carbon nanotubes, which may influence the quality control of products in the process of manufacturing, and the harm to human body and the natural environment is also an obstacle to its practical application and manufacturing.
An Appreciation – John Corboy, MD, FAAN

I offer my warmest congratulations to John Corboy, who is soon to end his tenure as editor of Neurology: Clinical Practice (NCP). The job of creating and nurturing a new journal is not trivial, and it takes considerable skill and sound insight. John stepped up and brilliantly succeeded. To appreciate this substantial accomplishment, I offer some background – a bit of an origin story.
High-voltage GaN HEMT evaluation in micro-inverter applications

The purpose of this work is to identify potential problems through an initial implementation and testing of an in-house designed GaN device based micro-inverter. The switching performance of high-voltage gallium nitride devices was first characterized to ensure successful implementation of a full-bridge micro-inverter. The inverter phase-leg output voltage before filter was evaluated with two different pulse-width-modulation schemes: dual modulation and discontinuous modulation. A 500-W full-bridge micro-inverter prototype was designed and tested to verify the performance of the two modulation schemes. With 100-kHz effective switching frequency, harmonic spectra and power stage efficiency were evaluated. Although the device operating condition is different, these two schemes show identical switching loss and harmonic performance when their effective switching frequency is the same. Experimental results in this implementation indicate that the circuit design and layout are critical as the parasitic inductance and capacitance coupling may cause shot-through fault and impact the switching efficiency. More efforts are needed in circuit design and layout to fully exploit the advantage of the ultrafast switching GaN devices.
Private and public ownership in outpatient substance abuse treatment: Do we have a two-tiered system?

As investor-owned organizations increase their presence in the mental health care sector, questions emerge regarding the effects of ownership type on service delivery. One important question is whether ownership is related to patient access to care for persons requiring treatment for substance abuse problems. Using data from a 1995 national survey of outpatient substance abuse treatment units, the authors investigate whether there are differences in measures of patient access to care among investor-owned, not-for-profit, and public provider organizations. Results indicate investor-owned units cater to and serve a clientele that differs from that of not-for-profit and public units, suggesting the presence of a two-tiered system of substance abuse treatment.
Chapter 71 Procurement Contracting

Publisher Summary Purchases by government agencies from private sector firms are often initiated by solicitation of bids to supply the desired items. Payment to the firm that is awarded the supply contract may be determined by (a) the bid price or (b) bid price plus a share of the difference between observable production cost and the bid price or (c) observable production cost plus an additional fee that may be a function of costs. Interest in the theory and behavior of procurement contracting stems mainly from two features of the political economy: (a) government may have multiple, possibility-conﬂicting objectives in procurement; and (b) there may be an asymmetry in knowledge of some components of firms' production costs. One objective that government is likely to have in procurement contracting is minimization of the budgetary cost of making the purchases. Another objective that the government may have in conducting its economic activities, including procurement, may be the promotion of allocative efficiency. As we shall see, budgetary cost minimization and economic efficiency maximization can be conﬂicting objectives when there is a cost information asymmetry.
Tenure and Turnover: Re-Creating Markets for Tenured Faculty

We argue that tenure leads to a virtual closure of active markets for tenured faculty; if tenured professors cannot be fired, this generally means that they cannot also move to another academic position. This market closure creates institutional rigidity and reduces faculty incentives. As a solution to these problems, we propose re-creating markets for tenured faculty by opening up a 'trade' in professors across departments within the same college, and across colleges.
Adult Attachment and Well-Being: Dimensions of Differentiation of Self as Mediators

This study investigated adult attachment dimensions as predictors of interpersonal forgiveness, positive emotionality, and social justice commitment through dimensions of differentiation of self. The sample consisted of 209 master’s level graduate students at a Protestant-affiliated university in the United States. Results revealed that higher attachment anxiety was associated with decreased differentiation of self and that decreased differentiation of self was then associated with lower levels of interpersonal forgiveness, positive emotionality and social justice commitment. Increased attachment avoidance was similarly associated with decreased differentiation of self, which then corresponded to lower levels of interpersonal forgiveness, positive emotionality and social justice commitment. Findings are discussed in the context of existing theory and research, and attention is given to the implications for clinical training and practice and future research.
The Effects of a High Fat Diet on Leptin mRNA, Serum Leptin and the Response to Leptin Are Not Altered in a Rat Strain Susceptible to High Fat Diet-Induced Obesity

Osborne-Mendel (OM) and S5B/Pl rats differ in their sensitivity to develop obesity when fed a high fat (HF) diet; OM rats become obese, whereas S5B/Pl rats remain thin. We have investigated the possibilities that either an impaired leptin response or resistance to leptin action underlies the sensitivity to this form of obesity in OM rats. In Experiment 1, OM and S5B/Pl rats fed a nonpurified diet were killed at d 0 or were fed either a HF (56% fat energy) or a low fat (LF, 10% fat energy) diet for 2 or 7 d. The HF diet increased serum leptin significantly by d 2 to levels that were similar in both rat strains. At 7 d, leptin levels were lower than at d 2 but remained higher than levels in the d 0 control groups. The leptin mRNA:18S RNA ratio in epididymal adipose tissue increased to higher levels in HF-fed OM rats than in S5B/Pl rats fed that diet. However, although the LF diet had no effect in S5B/Pl rats, it increased leptin mRNA levels in epididymal adipose tissue of OM rats compared with the controls fed the nonpurified diet. In Experiment 2, OM and S5B/Pl rats were fed HF or LF diets for 5 wk. At that time, their feeding response to a range of leptin doses (0, 1, 5 or 10 microgram) given intracerebroventricularly was tested after overnight food deprivation. There was a similar dose-dependent reduction in energy intake in response to leptin in both OM and S5B/Pl rats. These responses were independent of the diet. The data suggest that the susceptibility of OM rats to HF diet-induced obesity is not related to either a loss of central sensitivity to leptin or a failure to enhance leptin production acutely, although the failure to maintain chronically increased levels of serum leptin could contribute to the obesity.
Sensitivity of surface plasmon dispersion and damping to alkali adsorption

Abstract I have studied the sensitivity to alkali adsorption of the linear coefficients of surface plasmon dispersion and damping, through the use of self-consistent surface potential barriers which have been shown by Lang to give a good account of the work function changes due to such adsorption. The coefficient of dispersion increases strongly with alkali adsorption on an r S = 2 substrate, while the coefficient of damping changes less.
Iowa radon leukaemia study: a hierarchical population risk model for spatially correlated exposure measured with error

This paper presents a Bayesian model that allows for the joint prediction of county-average radon levels and estimation of the associated leukaemia risk. The methods are motivated by radon data from an epidemiologic study of residential radon in Iowa that include 2726 outdoor and indoor measurements. Prediction of county-average radon is based on a geostatistical model for the radon data which assumes an underlying continuous spatial process. In the radon model, we account for uncertainties due to incomplete spatial coverage, spatial variability, characteristic differences between homes, and detector measurement error. The predicted radon averages are, in turn, included as a covariate in Poisson models for incident cases of acute lymphocytic (ALL), acute myelogenous (AML), chronic lymphocytic (CLL), and chronic myelogenous (CML) leukaemias reported to the Iowa cancer registry from 1973 to 2002. Since radon and leukaemia risk are modelled simultaneously in our approach, the resulting risk estimates accurately reflect uncertainties in the predicted radon exposure covariate. Posterior mean (95 per cent Bayesian credible interval) estimates of the relative risk associated with a 1 pCi/L increase in radon for ALL, AML, CLL, and CML are 0.91 (0.78-1.03), 1.01 (0.92-1.12), 1.06 (0.96-1.16), and 1.12 (0.98-1.27), respectively.
Decentralized stabilization of nonlinear continuous time delay systems

Abstract The stabilization of a nonlinear, large scale, multivariable, decentralized system with delays in the interconnections is considered. The sufficient stabilization condition is established whereby the system under consideration is always stabilizable, provided the nonlinear parts of the subsystems satisfy the so-called “sector condition”, while the time delays only appear in interconnection terms.
The role of endoscopy in bariatrics: past, present, and future.

Abstract The exponential increase in the rate of obesity and its associated co-morbidities has increased the demand for bariatric surgery. Over the past few decades, surgical weight reduction by gastric restriction, malabsorption, or a combination of both has been the preferred approach to achieve sustained weight loss in the morbidly obese. Although extremely effective, surgical procedures carry significant complications and risk with mortality rates of 1%. Because of the cost, surgical risk, and complications, there is a demand for less invasive procedures. Endoscopic approaches include placement of endoluminal space-occupying devices, stapling devices to reduce gastric volume, barrier devices to reduce small bowel absorptive area, and methods to regulate gastric emptying. Current and ongoing studies have delivered promising results across many aspects of endoscopic approaches. However, many technical obstacles still exist that have to be resolved with further research before endoscopic bariatrics can b...
Microstructure and interface properties of laterally oxidized Al x Ga 1- x As

The microstructure and interface properties of AlxGa1- xAs materials that have been laterally oxidized in wet N2 for several compositions (x equals 0.80, 0.82 . . . 1.00) and temperatures (360 degrees Celsius to 450 degrees Celsius) have been studied. The micro-structure is found to be relatively insensitive to composition and oxidation temperature. The oxidation forms an amorphous solid solution (AlxGa1-x)2O3 that transforms to polycrystalline, (gamma) -(AlxGa1-x)2O3 under electron beam exposure in the electron microscope. Evidence suggests a small fraction of crystalline (AlxGa1- x)2O3 is formed via post oxidation annealing of the oxide. The level of hydrogen present in the oxidized layers is 1.1 multiplied by 1021 cm-3, which is too low for the amorphous phase observed to be a hydroxide rather than an oxide. The amount of As in the layer is reduced to less than 2 atm%, and no As precipitates are observed. The (AlxGa1-x)2O3/GaAs interface is abrupt, but prolonged oxidation will cause the GaAs to oxidize at the internal interfaces. The reaction front between the oxidized and the unoxidized AlxGa1-xAs has a 10 to 20 nm-wide amorphous zone that shows a different contrast than the remainder of the amorphous oxide and is stable under electron irradiation.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Case Study on Collective Cognition and Operation in Team-Based Computer Game Design by Middle-School Children.

This case study examined team-based computer-game design efforts by children with diverse abilities to explore the nature of their collective design actions and cognitive processes. Ten teams of middle-school children, with a high percentage of minority students, participated in a 6-weeks, computer-assisted math-game-design program. Essential processes of collective design cognition and operation emerged from the data: (a) collective exploration of design constraints during problem framing, (b) aggregation of identity, experience, and memory for collective solution generation, and (c) development of coalition and task interdependence during design execution. Salient contexts supporting collective design included team-role fulfillment with presence of leadership and scaffolding for mutuality in design talk. The study findings also indicated perceived learning of school children during collaborative math-game design.
Protein and Metabolizable Energy Requirements of Hand-Fed Squabs from Hatching to 28 Days of Age

Abstract Incubator-hatched squabs were hand fed slurries containing 14% diet and 86% water by weight for the 1st 4 days, followed by 20% diet and 80% water for the next 2 to 3 days. From Days 7 to 28, the slurry contained 25% diet and 75% water. A diet containing about 61% isolated soybean protein, 8.9% soybean oil, 21.5% glucose, 4% CaHPO4·2H2 O, and 1.3% CaCO3 supplemented with vitamins and trace elements supported the optimum growth of squabs for the first 7 days. It contained 3,675 kcal metabolizable energy (ME)/kg and 53.3% crude protein (CP). The composition of the optimum diet for feeding from Days 7 to 289 was as follows: corn starch, 58.37%; isolated soybean protein, 23.1%; cellulose, 8.0%; soybean oil, 3.0%; CaHPO4·2H2 O, 3.0; methionine, .3%; CaCO3, 1.0; plus vitamins and trace minerals. This diet provided 3,200 kcal ME/kg and 20% CP.
Assemblies of Titanium Dioxide-Polystyrene Hybrid Nanoparticles for Dielectric Applications

Macroscopic assemblies of hybrid nanoparticles composed of titanium dioxide core surrounded by covalently grafted polystyrene corona have been prepared by a combination of phosphonate coupling and “click” chemistry. The attached polymer chains existed in the brush regime, with grafting density inversely proportional to the degree of polymerization. Solution casting afforded preparation of robust films of the composite material where all the polymer chains were covalently bound to the uniformly distributed inorganic particles. Inorganic content from 60 to 80 wt % (27 to 50 vol %) was obtained by varying the molecular weight of polystyrene as well as by using the mixture of high and low molecular weight polymer for grafting. The TiO2 grafted with 105 g/mol polystyrene had a volume fraction of nanoparticles of 27% and exhibited glass transition at 110 °C and ∼100% extensibility above Tg. Thin films of this material had a dielectric constant of 6.4 and a dielectric loss of 0.04 at 1 kHz.
Microfracture patterns of abrasive wear striations on teeth indicate directionality.

A method is described that will indicate the direction that an abrasive particle was traveling as it scored the surface of a brittle material. Light and scanning electron micrographs of glass, dentine, and enamel abraded by loose sand, steel carbide, and diamond indicate that partial Hertzian fracture cones are formed at the margins of wear striations during abrasion. The bases of these fracture cones face in the direction of travel of the abrasive particle and, therefore, indicate directionality. Because this method is based only on the consistent geometry of fracturing of brittle materials, it is independent of the loading of the abrasive particle. The only other method available to determine directionality of striations is unreliable since it uses the width of striations, and, hence, is dependent upon a consistent loading regime of the abrasive particle. This new method has direct application for determining the direction of movement of the jaws during mastication in living or fossil animals.
Topographic stress perturbations in southern Davis Mountains, west Texas 2. Hydrogeologic implications

[1] As part of a regional groundwater investigation, geophysical logs were obtained in two municipal water wells located near the west Texas city of Alpine. These boreholes are 252 and 285 m deep and penetrate extrusive rocks of Tertiary age. The deeper well was drilled in the central valley and the other along the northern flank of an east-west trending valley-ridge setting. Analysis and interpretation of the logs reveal that the two wells are subjected to significantly different stress environments because of topographic effects and exhibit significantly different hydrogeologic properties. Water production is associated with two specific types of features common to both wells: (1) the upper and lower contacts of a dense trachyte unit located in the shallow part of the wells and (2) deeper zones of highly fractured rocks within the interior of a basalt formation. The transmissivity of the trachyte boundaries is twice as large in the central valley well as it is in the ridge flank well, whereas the transmissivity of the deeper basalts is an order of magnitude greater in the flank well than it is in the central well. This discrepancy is examined from the perspective of rock failure, fracture opening, and flow enhancement by computing values for a Drucker-Prager stability factor that is based on the magnitudes of the normal and deviatoric stress invariants as a function of depth. Thus the field measurements and subsequent stress analysis offer evidence of a coupled tectonic-hydrologic interaction at this site.
Selective increase in pericentral oxygen gradient in perfused rat liver following ethanol treatment

The oxygen gradient across the liver lobule was measured in isolated, hemoglobin-free perfused livers from control and ethanol-treated rats using micro-light guides and miniature oxygen electrodes. Both techniques yielded similar values for the lobular, periportal and pericentral oxygen gradients. Oxygen uptake increased 33% in livers from rats treated with ethanol for 4 to 6 weeks. In addition, the pericentral oxygen gradient increased by 100%, but the periportal gradient was unchanged. These observations suggest that chronic ethanol treatment may increase the rate of cellular respiration in pericentral regions of the liver lobule selectively. One possible explanation for a region-specific effect of ethanol may be ethanol-induced inhibition of glycolysis which predominates in pericentral hepatocytes.
Human health and chemical mixtures: an overview

Unlike laboratory animals, people are rarely exposed to a single hazardous chemical. However, most of the information documenting adverse human health effects from environmental and occupational contaminants has come from studies focused on exposure to single chemicals, and there is little information available on how two or more contaminants affect humans. Most information on the effects of mixtures comes from animal systems and limited investigations of isolated human cells in culture, even though the study of mixtures in such systems has also been neglected. Two or more compounds may show additive, antagonistic, or synergistic interactions or may act on totally different systems and thus not interact. Furthermore, even a single chemical may have multiple effects and affect more than one organ system. Effects may vary with age, and metabolites may have totally different actions from the parent compound. This paper will review the variety of health effects in humans that may result from environmental contaminants and discuss how such contaminants may interact with each other. We will also present examples on how different contaminants interact from toxicologic studies of polychlorinated biphenyls performed as part of our Albany, New York, Superfund Basic Research Program project.
Second- and higher-order waveguide grating filters. 1: Theory.

A study of second- and higher-order waveguide grating filters is considerably complicated by the fact that the coupling between the guided waves and the radiated waves has to be taken into account. In this paper, we review the theoretical calculations of the spectral response of these grating filters that have been reported by several authors and present a new approach based on the use of the Green’s functions of the waveguide structure. Excellent agreement is found between the results of our method of calculation and the results of other, more rigorous but much more complicated, methods. The Green’s function method is thus a reasonably simple but fairly accurate method for calculating the spectral response of grating filters.
Fluorogenic probes for monitoring peptide binding to class II MHC proteins in living cells

A crucial step in the immune response is the binding of antigenic peptides to major histocompatibility complex (MHC) proteins. Class II MHC proteins present their bound peptides to CD4+ T cells, thereby helping to activate both the humoral and the cellular arms of the adaptive immune response. Peptide loading onto class II MHC proteins is regulated temporally, spatially and developmentally in antigen-presenting cells1. To help visualize these processes, we have developed a series of novel fluorogenic probes that incorporate the environment-sensitive amino acid analogs 6-N,N-dimethylamino-2-3-naphthalimidoalanine and 4-N,N-dimethylaminophthalimidoalanine. Upon binding to class II MHC proteins these fluorophores show large changes in emission spectra, quantum yield and fluorescence lifetime. Peptides incorporating these fluorophores bind specifically to class II MHC proteins on antigen-presenting cells and can be used to follow peptide binding in vivo. Using these probes we have tracked a developmentally regulated cell-surface peptide-binding activity in primary human monocyte-derived dendritic cells.
Characterization of filled elastomers by dynamic strain amplification at high frequencies

Abstract A high-frequency dynamic mechanical tester was used to characterize gum elastomers and their carbon black-filled counterparts. The objectives were to test a model for strain amplification in tensile deformation dynamically at high frequencies, to test further a previously proposed mechanism for elastomer reinforcement in shear and tensile deformation at high frequencies, and to evaluate the overall performance of a high-frequency dynamic mechanical analyzer. Differences in tensile and shear behavior of the compounds were found to be consistent with previous results, as were the effects of strain amplification, which were greater at higher frequencies and lower strains.
Current status of aquatic species biologics.

SummaryNo vaccine is a substitute for good managementand diligent biosecurity in an aquaculture facility. It isalways important to ensure the best water quality pos-sible, provide quality nutrition, avoid overcrowding oftanks and raceways, remove dead fish to preventpathogen buildup and spread, and reduce or eliminateunnecessary stress on fish. Use of a preventive medi-cine vaccine program and improved management canhelp ensure good health in a fish population andreduce the industries’ use of therapeutic agents. a K-Dtect, DiagXotics Inc, Wilton, Conn. b Kwik-Dtect, DiagXotics Inc, Wilton, Conn. References 1. Sustainable agriculture. The World Bank Group. Availableat: lnweb18.worldbank.org/ESSD/ardext.nsf/26ByDocName/Fisher-iesAquacultureAquaculture. Accessed Aug 9, 2004.2. USDA, Animal and Plant Health Inspection Service,Veterinary Services. National Aquaculture Program. Available at:www.aphis.usda.gov/vs/aqua/. Accessed Aug 9, 2004.3. Lightner DV. The penaeid shrimp viruses IHHNV and TSV:epizootiology, production impacts and role of international trade intheir distribution in the Americas.
Efficient parallel algorithms for breadth first spanning forests of general graphs

Ghosh and Bhattacharjee propose [2] (Intern. J. Computer Math., 1984, Vol. 15, pp. 255-268) an algorithm of determining breadth first spanning trees for graphs, which requires that the input graphs contain some vertices, from which every other vertex in the input graph can be reached. These vertices are called starting vertices. The complexity of the GB algorithm is O(log2 n) using O{n 3) processors. In this paper an algorithm, named BREADTH, also computing breadth first spanning trees, is proposed. The complexity is O(log2 n) using O{n 3/logn) processors. Then an efficient parallel algorithm, named- BREADTHFOREST, is proposed, which generalizes algorithm BREADTH. The output of applying BREADTHFOREST to a general graph, which may not contain any starting vertices, is a breadth first spanning forest of the input graph. The complexity of BREADTHFOREST is the same as BREADTH.
Technics and Architecture: The Development of Materials and Systems for Buildings

This illustrated history focuses on a neglected aspect of architecture, the technics of building form. Concentrating on developments in Europe and North America from the Industrial Revolution to the present, the author surveys the ways in which new materials, methods, and systems were discovered and tested, and the ways in which they succeeded or failed. Elliott tells the story in two parts, first covering materials - such as wood, masonry, terracotta, iron and steel, glass, cement, and reinforced concrete - and then systems - including lighting protection, sanitation, lighting, heating, air conditioning, elevators and escalators, fire protection, structural engineering and acoustics.