cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal Discrete Measures for Potentials: Polarization (Chebyshev) Constants

This chapter investigates optimal discrete measures from the perspective of a max-min problem for potentials on a given compact set A. More precisely, for a kernel \(K:A\times A \rightarrow \mathbb {R}\cup \{+\infty \}\), the so-called polarization (or Chebyshev) problem is the following: determine N-point configurations \(\{x_j\}_{j=1}^N\) on A so that the minimum of \(\sum _{j=1}^NK(x, x_j)\) for \(x\in A\) is as large as possible. Such optimization problems relate to the following practical question: if \(K(x, x_j)\) denotes the amount of a substance received at x due to an injector of the substance located at \(x_j\), what is the smallest number of like injectors and their optimal locations on A so that a prescribed minimal amount of the substance reaches every point of A?
31P NMR Spectroscopy of Brain and Heart

It was in 1974 when Hoult first applied NMR techinque to measure metabolites containing phosphorous in rat muscle. Moon and Richards demonstrated that 31P NMR can be used to measure intracellular Ph. They were great steps forward in understanding the fine regulation of cellular energy metabolism in comparison to the classical biochemical techniques, since the method is nondestructive and it gives a continuous monitoring of phosphate metabolites. Using this method, the concentrations of ATP, phosphocreatine, sugar phosphate, and inorganic phosphates were monitored on frog gastrocnemius (Burt, Dawson, Gadian), isolated hearts and recently on all the perfusable organs under different conditions (Gadian, Nunnally, Cohen). The first in vivo 31P NMR experiment was carried out by Chance et al, who demonstrated the possibility of monitoring the levels of phosphorous containing metabolites of brain tissue in vivo. All these studies were done with relatively small bore magnets (1–3cm) limiting the extent of these experiments.
A cognitive framework to plan for the future of transportation

Automated, connected, electrified, and shared mobility will be cornerstones of the transportation future. Research to quantify the potential benefits and drawbacks of practice, and to identify barr...
State of eHealth in Cancer Care: Review of the Benefits and Limitations of eHealth Tools.

Background eHealth has the potential to improve patient access to care through the use of various tools. Objectives This article provides a review of some eHealth technologies, including a discussion of their benefits and limitations. An overview of studies using eHealth technologies are summarized, and future directions are explored. Methods A review of the eHealth literature was conducted, with a focus on outcomes of telehealth interventions in cancer care. Findings eHealth can transform health care by expanding the reach of clinical cancer care. Examples of this expansion of care include patients who live in remote areas with limited access to oncology providers, patients who find travel challenging, and patients who prefer the convenience of communicating with their provider from their home. Such telehealth interventions can increase patient satisfaction, but additional research is needed to further evaluate patient outcomes.
Heterogeneity of Glucose Transport in Lung Cancer

Increased glucose uptake is a known hallmark of cancer. Cancer cells need glucose for energy production via glycolysis and the tricarboxylic acid cycle, and also to fuel the pentose phosphate pathway, the serine biosynthetic pathway, lipogenesis, and the hexosamine pathway. For this reason, glucose transport inhibition is an emerging new treatment for different malignancies, including lung cancer. However, studies both in animal models and in humans have shown high levels of heterogeneity in the utilization of glucose and other metabolites in cancer, unveiling a complexity that is difficult to target therapeutically. Here, we present an overview of different levels of heterogeneity in glucose uptake and utilization in lung cancer, with diagnostic and therapeutic implications.
Merging Metagenomics and Spatial Epidemiology To Understand the Distribution of Antimicrobial Resistance Genes from Enterobacteriaceae in Wild Owls.

ABSTRACT Antimicrobial resistance (AMR) is a well-documented phenomenon in bacteria from many natural ecosystems, including wild animals. However, the specific determinants and spatial distribution of resistant bacteria and antimicrobial resistance genes (ARGs) in the environment remain incompletely understood. In particular, information regarding the importance of anthropogenic sources of AMR relative to that of other biological and ecological influences is lacking. We conducted a cross-sectional study of AMR in great horned owls (Bubo virginianus) and barred owls (Strix varia) admitted to a rehabilitation center in the midwestern United States. A combination of selective culture enrichment and shotgun metagenomic sequencing was used to identify ARGs from Enterobacteriaceae. Overall, the prevalence of AMR was comparable to that in past studies of resistant Enterobacteriaceae in raptors, with acquired ARGs being identified in 23% of samples. Multimodel regression analyses identified seasonality and owl age to be important predictors of the likelihood of the presence of ARGs, with birds sampled during warmer months being more likely to harbor ARGs than those sampled during cooler months and with birds in their hatch year being more likely to harbor β-lactam ARGs than adults. Beyond host-specific determinants, ARG-positive owls were also more likely to be recovered from areas of high agricultural land cover. Spatial clustering analyses identified a significant high-risk cluster of tetracycline resistance gene-positive owls in the southern sampling range, but this could not be explained by any predictor variables. Taken together, these results highlight the complex distribution of AMR in natural environments and suggest that both biological and anthropogenic factors play important roles in determining the emergence and persistence of AMR in wildlife. IMPORTANCE Antimicrobial resistance (AMR) is a multifaceted problem that poses a worldwide threat to human and animal health. Recent reports suggest that wildlife may play an important role in the emergence, dissemination, and persistence of AMR. As such, there have been calls for better integration of wildlife into current research on AMR, including the use of wild animals as biosentinels of AMR contamination in the environment. A One Health approach can be used to gain a better understanding of all AMR sources and pathways, particularly those at the human-animal-environment interface. Our study focuses on this interface in order to assess the effect of human-impacted landscapes on AMR in a wild animal. This work highlights the value of wildlife rehabilitation centers for environmental AMR surveillance and demonstrates how metagenomic sequencing within a spatial epidemiology framework can be used to address questions surrounding AMR complexity in natural ecosystems.
Development of a fully connected residual neural network for directional gamma ray detection

Directional detection plays an important role in the search for rogue or illicit radioactive sources but is often complicated by Poisson statistics, large distances, and various sources of noise. A...
A General Framework for Compositional Network Modeling

We advocate for an approach to network modeling and analysis based on a common intermediate language. Unlike today, where each tool builds a custom model and analysis engine for its target network functionality, we argue that network functionality should be expressed in a common language. This approach makes it easier to expand formal analysis to new functionality and analyze interactions between dependent functionalities (e.g., routing and packet filtering). We demonstrate the feasibility of this approach by developing an intermediate language called Zen and three different analyses for programs in that language. For representative data plane and control plane functionalities, we find that Zen reduces the modeling effort by an order of magnitude, while providing analysis performance that matches custom tools.
Defining the clinician’s role in mitigating financial toxicity: an exploratory study

Financial toxicity describes the financial burden imposed onto patients by a cancer diagnosis and is a growing concern. Many clinicians do not currently address financial toxicity despite patients’ desire for them to do so. Current literature explores physicians’ perspectives but does not clearly define an actionable role clinicians can take to address financial toxicity. We sought to fill this gap by first assessing clinicians’ perspective on their role in alleviating financial toxicity at our institution. We subsequently aimed to identify current barriers to mitigating financial toxicity and to garner feedback on clinician-oriented interventions to address this growing problem. We developed an 18-item electronic, anonymous survey through Redcap. We invited all oncology clinicians including attending physicians, advance practice providers, and trainees at our institution to participate. A total of 72 clinicians (30%) completed the survey. The majority agreed that clinicians have a role in addressing cost. The top three barriers to discussing cost with patients were knowledge of out of pocket costs, time, and awareness of resources. Less than half of respondents used an existing comparative cost tool to incorporate cost consciousness into treatment decisions. The most desired intervention was an institutional resource guide. In open-ended comments, the most common barrier described was transparency of out of pocket costs, and the most common solution proposed was a multi-disciplinary approach to addressing financial concerns patient face. Improving price transparency, incorporating existing resources into clinical practice, and streamlining multi-disciplinary support may help overcome barriers to addressing financial toxicity.
Applications of the J-integral to dynamical problems in geotechnical engineering

Abstract We formulate a path-independent J -integral for the elastodynamic problem expressed in the frequency domain. We show that the path-independence of the integral can be exploited in order to derive ansatz-free identities and rigorous inequalities in certain problems arising in geotechnical engineering. By way of illustration, we specifically consider the problem of assessing seismic pressures on retaining walls. We show that the bounds for the earth thrust derived from the frequency-domain dynamic J -integral improve upon previous heuristic and conjectured bounds.
Convex Duality for Finite-Fuel Problems in Singular Stochastic Control

Upon introducing a finite-fuel constraint in a stochastic control system, the convex duality formulation can be set up to represent the original singular control problem as a minimization problem over the space of vector measures at each level of available fuel. This minimization problem is embedded tightly into a related weak problem, which is actually a mathematical programming problem over a convex,w*-compact space of vector-valued Radon measures. Then, through the Fenchel duality principle, the dual for the finite-fuel control problems is to seek the maximum of smooth subsolutions to a dynamic programming variational inequality. The approach is basically in the spirit of Fleming and Vermes, and the results of this paper extend those of Vinter and Lewis in deterministic control problems to the finite-fuel problems in singular stochastic control. Meanwhile, we also obtain the characterization of the value function as a solution to the dynamic programming variational inequality in the sense of the Schwartz distribution.
High-speed lava flow infrasound from Kīlauea’s fissure 8 and its utility in monitoring effusion rate

The 2018 eruption of Kīlauea Volcano produced large and destructive lava flows from the fissure 8 (Ahu ‘aila ‘au) vent with flow velocities up to 17 m s−1, highly variable effusion rates over both short (minutes) and long (hours) time scales, and a proximal channel or spillway that displayed flow features similar to open channel flow in river systems. Monitoring such dynamic vent and lava flow systems is a challenge. Our results demonstrate that infrasound, combined with ground-based observations and imagery from unoccupied aircraft systems (UAS), can be used to distinguish vent degassing activity from high-speed lava flow activity. We use spectral characteristics and the infrasound frequency index (FI) to distinguish spillway infrasound from vent infrasound. Comparing FI with flow speeds derived from UAS videos reveals that spillway infrasound only occurs when flow speeds were sufficiently high to cause a supercritical flow state and breaking waves (Froude values > 1.7), and we propose that the spillway signals are produced primarily through the interaction of the turbulent lava-free surface with the atmosphere. We show that FI can also provide a means to track bulk effusion rate. Our results indicate that infrasound offers a new way to characterize lava flow channel hydraulics and is a powerful tool for monitoring effusive eruptions when high-speed flows are possible.
Using Transportation Accident Databases in Human Factors Research

Accident databases commonly contain factual information about the time and date of each accident, vehicle characteristics, number of persons killed and injured, and other kinds of factual data. These attributes of the environment and equipment are usually directly represented in databases. In contrast, detailed analysis of accident causes, including human factors information, are frequently not represented because they are much more difficult to obtain and code.This paper explores the suitability of transportation accident databases for use in human factors research. Given the goal of reducing the number and severity of transportation accidents, it is useful to use accident data as a tool to understand the common causes of accidents. Problems arise, however, because existing databases were typically not created explicitly for research purposes, and coding systems and file structures often omit or obscure useful information. Improved coding schemes and file structures that promote the use of databases for ...
The extremal properties of spatial stiffness matrices

In this paper, the structure and extremal properties of spatial stiffness matrices are investigated. From this work a better understanding of the spatial compliant behavior important in robot interaction tasks is attained. We develop a rank-1 decomposition of a spatial stiffness matrix which is independent of the coordinate frame used to describe the elastic behavior. We also identify the extremal properties associated with this decomposition. To attain better physical insight, analogies are drawn between this unique spatial stiffness matrix decomposition and the conventional eigenvalues decomposition of a translational stiffness matrix.
Improving wireless LAN performance via adaptive local error control

Wireless links can exhibit high error rates due to attenuation, fading, or interfering active radiation sources. To make matters worse, error rates can be highly variable due to changes in the wireless environment. Researchers and developers have explored a wide range of solutions to optimize communication in this difficult error environment, including traditional end-to-end solutions, link-layer solutions, and solutions involving layer four processing inside the network. A significant challenge is ensuring that systems with multiple layers of error control avoid compromising performance by duplication of effort. We argue and demonstrate that protocol-independent link-level local error control can achieve high communication efficiency even in a highly variable error environment, that adaptation is important to achieve this efficiency, and that inter-layer coexistence is achievable. The logical link control layer of our WaveLAN-based experimental LAN includes three error control mechanisms: local retransmission, adaptive packet shrinking, and adaptive error coding. Measurements generated on a variety of network topologies and trace-based error environments demonstrate the TCP performance improvements and good coexistence with TCP's end-to-end retransmission strategy.
Reprint of: Primary care physicians’ knowledge of the ophthalmic effects of diabetes

Abstract Objective Previous studies suggest that many patients with diabetes do not receive an annual dilated eye examination because of a lack of referrals from primary care physicians (PCPs). This study aims to determine the depth of knowledge of PCPs regarding diabetic eye disease. Design Cross-sectional assessment. Participants Ninety-seven PCPs. Methods An 8-question, multiple-choice assessment was administered over a 3-month period to 208 PCPs in attendance at continuing medical education conferences. Results Ninety-seven PCPs completed the assessment. Participants had a mean total score of 5.9 of 8 possible (73.8%). Questions regarding screening, clinical findings, and prevention were answered correctly by ≥81% of the respondents. However, questions regarding risk factors and complications were answered correctly by less than 35% of the respondents. No difference in scores was found based on the type of residency training received or the number of years in practice. Conclusions Although PCPs may require greater education in the complications and risk factors of diabetic eye disease, study participants demonstrated a good overall depth of knowledge regarding diabetic eye disease. Thus, previous reports of only 35% to 55% of patients with diabetes receiving an annual dilated fundus examination are likely not due to a lack of physician education.
Transdermal Rotigotine: A Clinically Innovative Dopamine-Receptor Agonist for the Management of Parkinson's Disease

Rotigotine is a highly lipophilic dopamine-receptor agonist and the first transdermally delivered agent to demonstrate efficacy and safety as monotherapy in early Parkinson's disease and to reduce "off" hours in levodopa-treated patients with advanced Parkinson's disease. The rotigotine pharmacophore is nonergolinic and demonstrates high affinity for dopamine D 2 and D 3 receptors. With once-daily application, the patch matrix provides continuous, nonfluctuating plasma drug levels at steady state, resulting in continuous and steady plasma and brain levels and striatal dopamine-receptor stimulation. In early Parkinson's disease, doses of rotigotine up to 8 mg/24 hours demonstrate comparable efficacy to ropinirole (at doses up to 12 mg/day); in advanced Parkinson's disease, doses of rotigotine up to 16 mg/24 hours demonstrate comparable efficacy and tolerability to pramipexole (at doses up to 4.5 mg/day). In the registration trials for early and advanced Parkinson's disease, the adverse effects most commonly observed with rotigotine were minor application site reactions, dizziness, nausea, and somnolence. Doses of transdermal rotigotine can be titrated to a maintenance dose within 2-3 weeks, and the once-daily regimen minimizes complexity of therapy. The transdermal delivery system is also an advantage when nonoral administration is desired, and the 24-hour, continuous, nonfluctuating drug levels can improve early morning and nocturnal symptoms of Parkinson's disease. Thus, transdermally delivered rotigotine is a clinically innovative and useful addition to the dopamine-receptor agonist class. This review summarizes the key pharmacologic and clinical data for rotigotine and provides a focused clinical context for its use in early-to-advanced Parkinson's disease, as well as a brief summary for its role in restless legs syndrome.
Cladograms with Path to Event (ClaPTE): A novel algorithm to detect associations between genotypes or phenotypes using phylogenies

Abstract Background Associations between genotype and phenotype provide insight into the evolution of pathogenesis, drug resistance, and the spread of pathogens between hosts. However, common ancestry can lead to apparent associations between biologically unrelated features. The novel method Cladograms with Path to Event (ClaPTE) detects associations between character-pairs (either a pair of mutations or a mutation paired with a phenotype) while adjusting for common ancestry, using phylogenetic trees. Methods ClaPTE tests for character-pairs changing close together on the phylogenetic tree, consistent with an associated character-pair. ClaPTE is compared to three existing methods (independent contrasts, mixed model, and likelihood ratio) to detect character-pair associations adjusted for common ancestry. Comparisons utilize simulations on gene trees for: HIV Env, HIV promoter, and bacterial DnaJ and GuaB; and case studies for Oseltamavir resistance in Influenza, and for DnaJ and GuaB. Simulated data include both true-positive/associated character-pairs, and true-negative/not-associated character-pairs, used to assess type I (frequency of p-values in true-negatives) and type II (sensitivity to true-positives) error control. Results and conclusions ClaPTE has competitive sensitivity and better type I error control than existing methods. In the Influenza/Oseltamavir case study, ClaPTE reports no new permissive mutations but detects associations between adjacent (in primary sequence) amino acid positions which other methods miss. In the DnaJ and GuaB case study, ClaPTE reports more frequent associations between positions both from the same protein family than between positions from different families, in contrast to other methods. In both case studies, the results from ClaPTE are biologically plausible.
A search for airborne particles of meteoritic origin

Abstract A year-long programme involving daily collections of atmospheric dust at several widely separated, isolated sites has been undertaken with the object of identifying particles that may be of extraterrestrial origin. The particles in question are opaque, shiny spherules with diameters less than 15 μ. They appear to be of a nature entirely different from that of the larger spheres abounding in densely populated areas. Their meteoritic origin is suggested by recent evidence regarding ablation of meteorites and by the fact that the rate of fall and the frequency distribution with size of these particles have been found to be the same at the various stations. The average rate of fall for each station was 1·1 spherules greater than 3 μ in diameter/cm 2 /day. Assuming that the density of the counted particles is that of magnetite, this rate corresponds to an annual accretion for the entire earth of about 5 × 10 8 kg of these particles.
Online but Off-Topic: Negotiating Common Ground in Small Learning Groups

There is not yet a great deal of research in formal online learning environments focusing on the seemingly “off-topic” conversations that small groups engage in as they complete learning tasks together. This study uses the theory of common ground as a framework to explore what participants are talking about when not discussing the concepts to be learned and how participants negotiate common ground in distance learning environments, including their use of computer-mediated communication (CMC) tools. The e-mail, discussion forum, and chat transcripts of 10 small groups comprised of experienced distance learners were investigated using computer-mediated discourse analysis (CMDA), particularly attending to functional moves exchanged while completing tasks. Findings were as follows. First, groups talked more about off-topic issues such as logistics, social and technology concerns than they did the concepts to be learned. Second, they used the discussion forum more than chat or e-mail, but they did not vary much in their choice of mode for talking about particular topics. Finally, the groups established common ground through being explicitly responsive, responsible, and relational. Implications are that highly structured learning tasks should be balanced with more open-ended discussions that require less attention to logistic detail, students should be encouraged to attend to grounding strategies, and students should remain in the same groups long enough to develop such strategies.
Modelling the growth and harvest yield of the giant kelp Macrocystis pyrifera

The giant kelp Macrocystis pyrifera is one of the largest and fastest growing seaweeds and is dominant over large areas of the west coast of North America. A model of its growth has been developed which describes plant biomass and production over the course of a year as a function of environmental parameters which affect the light flux. Such parameters include water clarity, spacing between plants, bottom depth, latitude, harvesting activity, and photosynthetic response (P max and I k ). Model results for a standard set of conditions (latitude 33°N, 3 m plant spacing, water absorbance of 0.115 m-1 and 12 m depth) yield a peak daily gross production of almost 6 g C m-2 d-1, peak daily net production of almost 3 g C m-2 d-1, and a peak specific growth rate of about 0.022 d-1. Annual gross production for this case is 1 567 g C m-2 yr-1; annual net production is 537 g C m-2 yr-1. These values are comparable to those from field measurements. Size and timing of biomass and production peaks are affected by changes in the parameters describing the light field, with peaks usually occurring later in the year for more adverse circumstances. Inhigher latitudes, the seasonal variation is so extreme that the plant could not last the year at 53° N in 12 m of water, although it is able to survive the year in shallower water. Harvesting has severe effects on biomass and production. Model results suggest that light limitation is a very important constraint on kelp growth that should not be overlooked. This implies that differences in parameters describing two environments must be considered when comparing results obtained at different locales.
Allostery in Hsp70 Chaperones Is Transduced by Subdomain Rotations

Hsp70s (heat shock protein 70 kDa) are central to protein folding, refolding, and trafficking in organisms ranging from archaea to Homo sapiens under both normal and stressed cellular conditions. Hsp70s are comprised of a nucleotide-binding domain (NBD) and a substrate-binding domain (SBD). The nucleotide binding site in the NBD and the substrate binding site in the SBD are allosterically linked: ADP binding promotes substrate binding, while ATP binding promotes substrate release. Hsp70s have been linked to inhibition of apoptosis (i.e., cancer) and diseases associated with protein misfolding such as Alzheimer's, Parkinson's, and Huntington's. It has long been a goal to characterize the nature of allosteric coupling in these proteins. However, earlier studies of the isolated NBD could not show any difference in overall conformation between the ATP state and the ADP state. Hence the question: How is the state of the nucleotide communicated between NBD and SBD? Here we report a solution NMR study of the 44-kDa NBD of Hsp70 from Thermus thermophilus in the ADP and AMPPNP states. Using the solution NMR methods of residual dipolar coupling analysis, we determine that significant rotations occur for different subdomains of the NBD upon exchange of nucleotide. These rotations modulate access to the nucleotide binding cleft in the absence of a nucleotide exchange factor. Moreover, the rotations cause a change in the accessibility of a hydrophobic surface cleft remote from the nucleotide binding site, which previously has been identified as essential to allosteric communication between NBD and SBD. We propose that it is this change in the NBD surface cleft that constitutes the allosteric signal that can be recognized by the SBD.
In Vivo Three-Dimensional Morphometric Analysis of the Lumbar Spinal Bony Canal in Healthy and Low Back Pain Patients

To accurately quantify the anatomic parameters of the lumbar spinal bony canal using a novel three-dimensional imaging technique based on in vivo CT three-dimensional models.Copyright © 2011 by ASME
The effect of receptor phase composition on the permeability of hairless mouse skin in diffusion cell experiments

Abstract The effect of different antimicrobial agents (0.1% and 0.04% formaldehyde and 0.002% NaN 3 ) in the receptor phase of diffusion cells and the influence of the length of time of exposure of hairless mouse skins in the diffusion cells to the receptor phases have been evaluated by determining their effect on the flux of theophylline in diffusion cell experiments. If the length of exposure to the receptor phase was 4 h before application of theophylline, the flux of theophylline was essentially the same regardless of the antimicrobial agent used. If 0.1% formaldehyde was the agent used, the flux of theophylline remained relatively constant regardless of the time of exposure to the receptor phase. For the other two agents (0.04% formaldehyde and 0.002% NaN 3 ) the flux of theophylline increased sharply with increased time of exposure. This result is apparently due to microorganism growth in the receptor phases containing 0.04% formaldehyde and 0.002% NaN 3 .
Caylor Receives 2009 Early Career Hydrologic Sciences Award

Kelly K. Caylor received the 2009 Early Career Hydrologic Sciences Award at the 2009 AGU Fall Meeting, held 14–18 December in San Francisco, Calif. The award is for significant early contributions to hydrologic science.
Controlled curing of adhesive complex coacervates with reversible periodate carbohydrate complexes

Periodate oxidation of carbohydrates with vicinal hydroxyl groups and aromatic ortho-dihydroxyphenyl groups has been employed extensively to initiate crosslinking or conjugation reactions in adhesive biomaterials. Periodate forms stable tridentate complexes with carbohydrates containing three appropriately configured hydroxyls, such as 1,2-O-isopropylidene-a-D-glucofuranose, that are not appreciably oxidized relative to carbohydrates with vicinal hydroxyls and ortho-dihydroxyphenyl groups. In the presence of 1,2-O-Isopropylidene-a-D-glucofuranose the rate of periodate oxidation of dihydroxy containing compounds is controlled by the rates of association and dissociation of the periodate-carbohydrate complex. By varying the ratio of 1,2-O-isopropylidene-a-D-glucofuranose to periodate the curing rate of adhesive complex coacervates was varied over a wide range. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
The effects of prototype medium on usability testing

Inconsistencies among testing methods and results in previous research prompted this study that builds upon a systematic usability testing research framework to better understand how interface medium influences users' abilities to detect usability flaws in applications. Interface medium was tested to identify its effects on users' perceptions of usability and abilities to detect usability problems and severe usability problems. Results indicated that medium has no effect on users' abilities to detect usability problems or perceptions of usability. However, results did indicate an interaction between the medium and the tested application in which users were able to identify significantly more usability problems on a higher fidelity medium using a particular application. Results also indicated that as users' perceptions of an application's usability increases, the users are less able to detect usability problems in that application. Usability testing should begin early in the design process, even if low fidelity mediums will be used.
Smad4 overexpression in hepatocellular carcinoma is strongly associated with transforming growth factor beta II receptor immunolabeling.

Abstract In the normal liver, the transforming growth factor beta (TGF-β) signaling pathway plays an important role in inhibiting hepatocyte growth. This effect is mediated through Smad4 (or Dpc4), a tumor-suppressor gene that affects gene transcription and controls cell growth. A loss of Smad4 is associated with carcinoma in a number of other organs, including the pancreas and colon. Despite these facts, several recent studies using cDNA microarrays have surprisingly shown overexpression of Smad4 in hepatocellular carcinoma (HCC). Because Smad4 plays a central role in the TGF-β signaling pathway, we hypothesized that activation of the TGF-β signaling pathway may explain Smad4 overexpression. To investigate this, 21 surgically resected HCCs were immunostained with antibodies to Smad4 and TGF-β receptor II. Tumor and normal liver tissues were stained in all cases, and expression in the tumor was scored in comparison to the nonneoplastic liver. Thirteen hepatic adenomas were also immunostained as a control group. The average age at resection was 58 ± 16 years for the 17 men and 4 women with HCC. TGF-β receptor II was weakly expressed in the hepatocyte cytoplasm of all normal livers and was overexpressed in 10 of 21 HCCs. Of these 10 HCCs increased Smad4 immunolabeling was also present in 10 of 10 cases. In contrast, of the 11 of HCCs that did not show TGF-β overexpression, only 1 showed increased Smad4 immunolabeling. Increased TGF-β receptor II and Smad4 labeling was associated with a worse nuclear grade and increased mitotic activity. For the hepatic adenomas, the 13 women had an average age at resection of 36 ± 10 years. Whereas 2 adenomas showed over expression of TGF-β receptor II, there was no Smad4 overexpression in any case. In conclusion, increased Smad4 protein expression in HCC is tightly linked to overexpression of TGF-β II receptors and is associated with increased mitoses and a worse nuclear grade. Hepatic adenomas only rarely show overexpression of TGF-β II receptors and did not show increased Smad4 labeling. The results from this study indicate that Smad4 protein overexpression is present in a subset of HCCs and is strongly correlated with immunostaining for TGF-β II receptor, findings that may represent activation or dysregulation of the TGF-beta signaling pathway. H UM P ATHOL 33:871-876. Copyright 2002, Elsevier Science (USA). All rights reserved.
A cooperative care model: Cardiologists and hospitalists reduce length of stay in a chest pain observation unit

Chest pain observation units are increasingly used to evaluate patients at low risk for cardiovascular events and are commonly staffed by cardiologists. The role of hospitalists in this setting has not been described. We assessed emergency department (ED) length of stay before and after adding hospitalists to the care team among 493 patients. Prior to intervention, median ED length of stay was 19.3 hours, which decreased to 11.0 hours with the addition of hospitalists (43% decrease, P <0.0001). No significant difference in 30-day cardiac event rate was observed (5% versus 6%, P = 0.68).
No evidence for interstellar proteins

The existence of a broad interstellar feature near 280 nm, previously announced in these Letters, is not contested. From astronomical and biochemical arguments it is shown that no quantitative measures of optical depth can be derived from the published data and that there is a great wealth of organic molecules which have absorptions at or near this wavelength interval. The amino acid tryptophan is one such molecule but the deduced spectrum does not satisfy two other properties of its spectrum.
Experiments on subcooled flow boiling heat transfer in a vertical annular channel

Abstract Experiments on subcooled flow boiling heat transfer are carried out in a vertical annular channel the inner wall of which is heated and the outer wall insulated. Refrigerant-113 is the working fluid. Flow boiling heat transfer data are reported at three mass velocities (579, 801, and 1102 kg m −2 s −1 ), three pressures (312, 277, and 243 kPa), and three inlet subcoolings (20.0, 30.0, and 36.5°C). A multiple-hysteresis phenomenon is identified. The measured wall heat transfer coefficients are compared with predictions by various correlations and an improvement of the Shah correlation for annuli is suggested.
Transient fuel-cladding deformation analysis of the in-pile H3 'TREAT' test with the 'SAS2A/DEFORM-II' code

Abstract A new model for the transient fuel-pin deformation analysis has been developed for oxide-fueled fast breeder reactors. The model, designated as DEFORM-II, is a module of the SAS2A fast-reactor accident analysis code, and is currently used for calculations of fuel behavior in unprotected overpower transients in FFTF and in support of the TREAT program at Argonne National Laboratory. DEFORM II has a new rheological model which allows a more general description of inelastic behavior in both fuel and cladding material with arbitrary yield surfaces, which can be specified temperature, strain, and strain rate dependent. The new model also recognizes some of the most important changes in both fuel and cladding behavior due to steady-state irradiation. This SAS2A/DEFORM-II code system has been used to analyze the transient fuel-cladding deformation for the H3 in-pile TREAT test, during which a pre-irradiated fuel pin was subjected to an overpower transient corresponding to a $0.5–1/sec power ramp in FFTF. The EBR-II irradiated pin was surrounded by a hexagonal array of six fresh FTR type pins in flowing sodium and placed in a mark-II loop. Of particular importance for the transient deformation results were the gap size and fuel porosity, which were taken from the destructive examination of a sibling pin. The measured transient power variations and coolant inlet conditions from the experiment were used for the deformation analysis. The code predictions agreed reasonably well with the observations for this test. A complete documentation of all material data used for the analysis of this test is given in the appendices.
Current controlled LPE growth of InP

Abstract Direct electric current was used in several experiments to successfully grow epitaxial layers of InP from a saturated melt of In at a constant furnace temperature of 650°C. The thickness of the grown layers ranged from 15 to 85 μm, for a growth period of 2 h and current densities of 4 to 20 A/cm 2 . The measured grown layer thicknesses were compared with calculated layer thicknesses based on the observed Peltier cooling. The results strongly suggest that the growth is mainly due to the electrotransport of phosphorus atoms to the interface and that the contribution of Peltier induced growth is negligible. The above studies have shown that excellent control of layer thickness and uniformity can be achieved by controlling the dc current flow across the interface between the substrate and the melt.
Two Phase Electrohydrodynamic Instability Micromixing

This work characterizes two phase electrohydrodynamic (EHD) instability micromixing of two immiscible organic and aqueous fluid phases. EHD mixing of the two phase microflow is promoted by creating an unstable flow profile by electrically inducing motion of the phase boundary. The aqueous phase is assumed to be infinitely conducting due to dissolved salt ions, while the organic phase is assumed to be non-conducting. As electrodes are biased, charges accumulate at the aqueous/organic interface. At a critical voltage the interface becomes unstable so that the aqueous and organic layers will mix. This is modeled for both inviscid and viscous flows using linear stability analysis considering the interfacial kinematic and stress conditions which predicts the stability criteria with a range of unstable wavenumbers which may be excited The mixing of an unstable “sausaging” and “kink” modes are visualized using epifluorescent microscopy of the dyed organic phase. The characteristic unstable wavenumbers predicted using linear stability theory are determined from the power spectrum of the captured images and compared to the analytical model. Onset of instability is seen at 40 volts RMS at a frequency of 250 kHz. This voltage corresponds to an electric field of Eo = 8 × 105 V/m across the organic phase. The instability becomes progressively more dynamic as the field strength is increased. The system recovers after the field is removed. At low field strengths the theoretical field and fastest growth wavenumbers for mixing compares favorably with the initially applied field whereas at higher field strengths the theoretical field is much larger than the initially applied field. This is attributed to the larger level of mixing and the ability of the instability to grow beyond the linear range while the electric field increases as the mixing process occurs due to entrainment of highly conductive fluid decreasing the effective dielectric spacing.Copyright © 2005 by ASME
Ex ante incentive efficient trading mechanisms without the private valuation restriction

Abstract The private valuation assumption found in most trading mechanism design papers rules out markets whose valuation structure generates externalities between traders. This paper characterizes the set of ex ante incentive efficient trading mechanisms for a large class of markets that do admit such externalities, and for bilateral trade markets establishes the impossibility of a first-best solution. Across a class of trading problems employing uniform priors and linear valuation structures, this paper also compares levels of market efficiency for varying numbers of traders.
The Possibilities of Using CdTe as a Gamma Spectrometer

Photopeaks have been resolved from monoenergetic gammas within the 122 to 840 keV range using 40 mm3 surface barrier CdTe detectors operated at room temperature and under less than full collection conditions. Presently available CdTe exhibits heavy charge trapping and the gamma spectra reflect the effect of trapping and detrapping under changes of temperature, bias, and clipping time.
The differentiation of escape and avoidance behavior in two thalamic areas in the cat.

Abstract Four cats were trained to hurdle a barrier to avoid a grid shock. When either electrode of a pair, one positioned in the nucleus centralis medialis (NCM) and the other in a lateral (VPL) nucleus of the thalamus, were used to stimulate these nuclei for the first time after the grid training all cats responded with avoidance. Repeated stimulation of the NCM led to increases in the rate of avoidance, but the converse happened with the VPL nucleus. Extinction and retraining first with one, then the other of the electrodes in all cats established that this effect was general. The results demonstrate that specific sensory nuclei (represented by the VPL nucleus) provide only cue function while nonspecific nuclei (i.e., the NCM) provide both cue and response maintenance functions.
Large Area High Density Sub-20 nm SiO2 Nanostructures Fabricated by Block Copolymer Template for Nanoimprint Lithography

We developed simple fabrication methods to effectively transfer the block copolymer nanopatterns to a substrate material. High aspect ratio, sub-20 nm nanopillar and nanohole structures are successfully fabricated in a SiO2 layer in large area format, and the versatile utilities of these nanostructures as nanoimprint molds are studied. Nanoimprint lithography using these molds makes it possible to easily replicate densely packed block copolymer nanotemplate patterns on arbitrary substrates in a short processing time by using a large variety of polymer materials, including functional materials such as conjugated polymers. In addition, the PDMS soft stamps with both nanohole and nanopillar pattern polarities, which are useful tools for soft lithography and transparent template applications, are also successfully fabricated using the pillar- and hole-type SiO2 molds. These soft stamps provide an effective way to fabricate controllable as well as reproducible plasmonic metal nanostructures with tunable surfac...
Optimized inversion-prepared gradient echo imaging.

Purpose: To implement a method using an extended phase graph (EPG)-based simulation to optimize inversion-prepared gradient echo sequences with respect to signal and contrast within the shortest acquisition time. Materials and Methods: A critical issue in rapid gradient-echo imaging is the effect of residual transverse magnetization between consecutive data acquisition windows. Various spoiling schemes have been proposed to mitigate this problem, and while spoiling is often considered to be perfect, imaging can be more truthfully described using the EPG. An EPG-based simulation is used to analyze and predict the image signal and contrast to serve as a basis for sequence optimization. Results: Fourteen biological phantom experiments and five brain imaging experiments on each of five healthy volunteers was performed to validate and verify the accuracy of the EPG-based simulation. In addition, two experiments on an in-cranial cadaver brain were performed to show the ability of the proposed method for improving overall image quality. Conclusion: From the experiment results, it is demonstrated that optimization of 3D magnetization-prepared rapid gradient-echo imaging sequences can be performed with an EPG-based simulation to manipulate the sequence parameters for generating images with highly specific signal and contrast characteristics for quantitative T1-weighted human brain imaging. J. Magn. Reson. Imaging 2012;36:748–755. © 2012 Wiley Periodicals, Inc.
Potential of Nurr1 interactions to disclose new Parkinson’s therapeutics

Nurr1 is an orphan nuclear receptor required for the postspecification differentiation and maintenance of the ventral midbrain dopaminergic neurons that are lost in Parkinson’s disease. In an effort to understand how the action of Nurr1 is regulated, we screened for and identified a new Nurr1-interacting protein, NuIP, that potentiates the transcriptional activity of Nurr1 and contains several protein motifs, suggesting a role in mediating signaling transduction. Herein, we review NuIP’s discovery and functions and propose a strategy to identify small molecules to augment Nurr1 activity through its interaction with NuIP. We speculate that drugs developed to modulate this pathway may have relevance for the treatment of Parkinson’s disease.
Tree recruitment in an empty forest.

To assess how the decimation of large vertebrates by hunting alters recruitment processes in a tropical forest, we compared the sapling cohorts of two structurally and compositionally similar forests in the Rio Manu floodplain in southeastern Peru. Large vertebrates were severely depleted at one site, Boca Manu (BM), whereas the other, Cocha Cashu Biological Station (CC), supported an intact fauna. At both sites we sampled small (� 1 m tall, ,1 cm dbh) and large (� 1 cm and ,10 cm dbh) saplings in the central portion of 4-ha plots within which all trees � 10 cm dbh were mapped and identified. This design ensured that all conspecific adults within at least 50 m (BM) or 55 m (CC) of any sapling would have known locations. We used the Janzen-Connell model to make five predictions about the sapling cohorts at BM with respect to CC: (1) reduced overall sapling recruitment, (2) increased recruitment of species dispersed by abiotic means, (3) altered relative abundances of species, (4) prominence of large-seeded species among those showing depressed recruitment, and (5) little or no tendency for saplings to cluster closer to adults at BM. Our results affirmed each of these predictions. Interpreted at face value, the evidence suggests that few species are demographically stable at BM and that up to 28% are increasing and 72% decreasing. Loss of dispersal function allows species dispersed abiotically and by small birds and mammals to substitute for those dispersed by large birds and mammals. Although we regard these conclusions as preliminary, over the long run, the observed type of directional change in tree composition is likely to result in biodiversity loss and negative feedbacks on both the animal and plant communities. Our results suggest that the best, and perhaps only, way to prevent compositional change and probable loss of diversity in tropical tree communities is to prohibit hunting.