cssi/SciSciGPT-SciSciNet huggingface dataset:
Acute HCV Treatment: What Should We Do in the DAA Era?

Acute hepatitis C infection is a growing concern in the USA, especially in light of the opioid epidemic. Prior treatment data consisted of trials in patients receiving interferon-based regimens. There is now emerging evidence regarding the safety and efficacy of direct-acting antivirals for the treatment of acute hepatitis C. This review summarizes the current evidence on the treatment of acute HCV in the DAA era. Certain populations, such as people who inject drugs, or HIV-positive men who have sex with men, may benefit from early treatment of acute HCV. As compared with chronic hepatitis C, shorter durations of treatment appear highly effective in acute infection, resulting in reduced viral transmission, as well as potentially reduced overall costs of care related to this disease. Further studies are needed to clarify the optimal drug combinations and treatment durations to achieve sustained virologic response in these patients.
Celebrating Fifty Years of David M. Young’s Successive Overrelaxation Method

It has been over fifty years since David M. Young’s original work on the successive overrelaxation (SOR) methods. This fundamental method now appears in all textbooks containing an introductory discussion of iterative solution methods. (Most often the SOR method appears after a presentation of Jacobi iteration and Gauss-Seidel iteration and before the conjugate gradient iterative method.) We present a brief survey of some of the research of Professor David M. Young, together with his students and collaborators, on iterative methods for solving large sparse linear algebraic equations. This is not a complete survey but just a sampling of various papers with a focus on some of these publications.
The viscosity of dilute solutions of 3 He in 4 He at low temperatures

Measurements of the viscosity of dilute solutions of 3He in 4He made by different groups show little agreement. Viscosities measured by Black et al.1and later by Fisk and Hall2 are quite different from those of Webeler and Allen3 and Bertinat et al.4 Webeler and Allen and Bertinat et al. used the torsional crystal method to measure lower viscosities, those of Bertinat et al. being an order of magnitude lower at low temperatures. The reason for this discrepancy is not known.
Association of Antibiotic Treatment Duration With Recurrence of Uncomplicated Urinary Tract Infection in Pediatric Patients

Background: Gaps and inconsistencies in published information about optimal antibiotic treatment duration for uncomplicated urinary tract infection (UTI) in pediatric patients pose a dilemma for antibiotic stewardship. Objective: Evaluate the association of antibiotic treatment duration with recurrence rates in children with new-onset cystitis or pyelonephritis. Methods: Retrospective cohort analysis of patients aged 2 to 17 years with new-onset cystitis or pyelonephritis and without renal/anatomical abnormality was conducted using Truven Health MarketScan Database for 2013-2015. Results: Of 7698 patients, 85.5% had cystitis, 14.3% pyelonephritis. Duration of antibiotic treatment was as follows: 3 to 5 days for cystitis (20.4%) or 7 (33.6%), 10 (44.2%), or 14 (1.8%) days for any UTI. Recurrence occurred in 5.5% of patients. Covariates associated with increased recurrence risk included pretreatment antibiotic exposure (odds ratio [OR] = 1.29; 95% CI = 1.06-1.57), pyelonephritis on diagnosis date (OR = 1.44; 95% CI = 1.03-2.00), follow-up visit during antibiotic treatment (OR = 3.21; 95% CI = 2.20-4.68), parenteral antibiotic (OR = 1.89; 95% CI = 1.33-2.69), and interaction of pyelonephritis diagnosis with nitrofurantoin monotherapy (OR = 3.68; 95% CI = 1.20-11.29). After adjustment for covariates, the association between duration of antibiotic treatment and recurrence was not significant (compared with 7 days: 10 days: OR = 1.07, 95% CI = 0.85-1.33; 14 days: OR = 0.89, 95% CI = 0.45-1.78). Conclusions and Relevance: Antibiotic treatment duration was not significantly associated with recurrence of uncomplicated UTI in a national pediatric cohort. Results provide support for shorter-course treatment, consistent with antimicrobial stewardship efforts.
Atomistic Structures of Zeolite-Templated Carbon

Zeolite-templated carbons (ZTCs) are a distinct class of porous framework materials in which a three-dimensional network of pores is contained between atomically thin, polycyclic hydrocarbon walls,...
Mechanism Analysis of Uncovering Coal in Crosscut and Gas Outburst Based on Flac3D

Zhao, Z. and Lei, Y., 2020. Mechanism analysis of uncovering coal in crosscut and gas outburst based on Flac3D. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 333–338. Coconut Creek (Florida), ISSN 0749-0208.Gas outbursts occur frequently in the process of uncovering coal in crosscut, so it is of great significance to study the outburst conditions of coal and gas in the process of tunneling. By establishing the model of these gas outbursts, we can obtain the function of the thickness of stone gate, gas pressure and gas outburst. With or without high pressure gas, the impact of high pressure gas during gas bursts is analyzed through the numerical simulation method. Based on the velocity, displacement, maximum principal stress and time curve of coal and rock interface in the center of roadway under two kinds of working conditions, the main conditions of gas bursts have been successfully verified. According to the results, in coal and gas outbursts, necessary conditions include the plastic zone penetration caused by high pressure gas storage and excavation disturbance, while sufficient conditions include the mutation of velocity field, displacement field and stress field in plastic zones.
Dynamic Primitives Facilitate Manipulating a Whip

Human dexterity far exceeds that of modern robots, despite a much slower neuromuscular system. Understanding how this is accomplished may lead to improved robot control. The slow neuromuscular system of humans implies that prediction based on some form of internal model plays a prominent role. However, the nature of the model itself remains unclear. To address this problem, we focused on one of the most complex and exotic tools humans can manipulate-a whip. We tested (in simulation) whether a distant target could be reached with a whip using a (small) number of dynamic primitives whose parameters could be learned through optimization. This approach was able to manage the complexity of an (extremely) high degree-of-freedom system and discovered five optimal parameters of a single movement that achieved the task. An internal model of the whip dynamics was not needed for this approach, thereby significantly relieving the computational burden of task representation and performance optimization. These results support our hypothesis that composing control using dynamic motor primitives may be a strategy which humans use to enable their remarkable dexterity. A similar approach may contribute to improved robot control.
Special Considerations for Secondary Surgery After Upper Extremity Transplantation.

BackgroundUpper extremity (UE) transplantation is a complex undertaking that may require emergent or elective secondary surgery (SS) days to years following transplant. Various patient and transpla...
Reducing Information Overload in Situated Visualization for Firefighting: A Human Factors Evaluation of User Interface Prototypes for Displaying Pre-Incident Planning Information

High profile structure fires, like the Grenfell Tower tragedy, have demonstrated that the quality of the information provided to firefighters arriving on the scene of an emergency is a matter of life or death. It has been suggested that access to structural information such as electronic building plans or unmanned aerial vehicle footage may bridge the information gap to help first responders build situation awareness at the incident scene. However, these technologies have not been fully evaluated from a human performance perspective. The use of pre-incident plans (PIPs), information captured systematically about a facility prior to an emergency, provides a way for firefighters to leverage data about a structure, increasing their efficiency and effectiveness in managing a fire and ultimately reducing fatalities and property damage. However, no standard interface configuration currently exists for presenting and displaying PIP information to firefighters digitally. This dissertation investigates the human factors implications associated with leveraging emerging technology in the form of 3D models and situated visualization techniques for displaying PIP information to fireground incident commanders. Through a series of mixed-method (qualitative and quantitative) studies, this dissertation directly captures user requirements and human performance data from firefighters in the form of focus groups, field data, surveys, and user study data. Based upon qualitative participant feedback and objective user study data, this series of studies evaluates the usability (efficiency, effectiveness, satisfaction) of three different user interface configurations. This data serves as a foundation for standardizing the way PIP information is presented to first responders. Further recommendations are suggested for how to effectively present and display PIP information to better support fireground incident commanders operating in dangerous and unpredictable environments.
A Multi-Pronged Evaluation For Image Normalization Techniques

While quantitative image features (radiomic) can be employed as informative indicators of disease progression, they are sensitive to variations in acquisition and reconstruction. Prior studies have demonstrated the ability to normalize heterogeneous scans using per-pixel metrics (e.g., mean squared error) and qualitative reader studies. However, the generalizability of these techniques and the impact of normalization on downstream tasks (e.g., classification) have been understudied. We present a multi-pronged evaluation by assessing image normalization techniques using 1) per-pixel image quality and perceptual metrics, 2) variability in radiomic features, and 3) task performance differences using a machine learning (ML) model. We evaluated a previously reported 3D generative adversarial network-based (GAN) approach, investigating its performance on low-dose computed tomography (CT) scans acquired at a different institution with varying dose levels and reconstruction kernels. While the 3D GAN achieved superior metric results, its impact on quantitative image features and downstream task performance did not result in universal improvement. These results suggest a more complicated relationship between CT acquisition and reconstruction parameters and their effect on radiomic features and ML model performance, which are not fully captured using per-pixel metrics alone. Our approach provides a more comprehensive picture of the effect of normalization.
Skull Segmentation from CBCT Images via Voxel-Based Rendering.

Skull segmentation from three-dimensional (3D) cone-beam computed tomography (CBCT) images is critical for the diagnosis and treatment planning of the patients with craniomaxillofacial (CMF) deformities. Convolutional neural network (CNN)-based methods are currently dominating volumetric image segmentation, but these methods suffer from the limited GPU memory and the large image size (e.g., 512 \(\times \) 512 \(\times \) 448). Typical ad-hoc strategies, such as down-sampling or patch cropping, will degrade segmentation accuracy due to insufficient capturing of local fine details or global contextual information. Other methods such as Global-Local Networks (GLNet) are focusing on the improvement of neural networks, aiming to combine the local details and the global contextual information in a GPU memory-efficient manner. However, all these methods are operating on regular grids, which are computationally inefficient for volumetric image segmentation. In this work, we propose a novel VoxelRend-based network (VR-U-Net) by combining a memory-efficient variant of 3D U-Net with a voxel-based rendering (VoxelRend) module that refines local details via voxel-based predictions on non-regular grids. Establishing on relatively coarse feature maps, the VoxelRend module achieves significant improvement of segmentation accuracy with a fraction of GPU memory consumption. We evaluate our proposed VR-U-Net in the skull segmentation task on a high-resolution CBCT dataset collected from local hospitals. Experimental results show that the proposed VR-U-Net yields high-quality segmentation results in a memory-efficient manner, highlighting the practical value of our method.
The Veterinary Antimicrobial Decision Support (VADS) System

This update summarizes progress specifically related to pharmacokinetic dataset categorization and clinical trial literature evaluation as well as challenges encountered in content development. The number of reference datasets available for regimen construction are constantly changing due to new data additions, but currently approximately 164 cattle datasets and 47 swine datasets are the basis for pharmacokinetic projections. Additional datasets are undergoing analysis for small ruminants and poultry. Pharmacokinetic datasets are categorized by animal species, age and health status as well as drug, drug form and injection site. Clinical trial literature is also being accumulated, evaluated and prepared for presentation on the VADS System website. As of the writing of this proceedings article, the VADS System development group is focusing on completing modeling of pharmacokinetic data and entering output on the website in the form of antimicrobial drug regimens combined with pathogen susceptibility profiles. The site is being constructed for ease of long-term maintenance in the form of modification of analysis techniques, addition of new data, and quality assurance of both data entry and data analysis. Data sources and analytical protocols are presented so as to be completely transparent to the user.
Knowledge, Time, and Logical Omniscience

Knowledge's acquisition happens in time. However, this feature is not reflected in the standard epistemic logics, e.g. S4 with its possible world semantics suggested by Hintikka in [1], and hence their applications are limited. In this paper we adapt these normal modal logics to increase their expressive power such that not only is what is known modeled but also when it is known is recorded. We supplement each world with an awareness function which is an augmentation of Fagin-Halpern's to keep track of the time when each formula is to be derived. This provides a new response to the logical omniscience problem. Our work originates from the tradition of study of Justification Logic , also known as Logic of Proofs , LP , introduced by Artemov ([2],[3],[4]). We will give the axiom systems of the models built here, accompanied with soundness and completeness results.
New half-range differential approximation for spherically-symmetric radiative transfer.

A new half-range differential approximation for radiative transfer with spherical symmetry is presented. The development is motivated by the various failures of existing differential approximations in determining emissive-power distributions and heat transfer for concentric-spheres problems. The new approach represents a modification of the four-moment double spherical-harmonics method, to which it reduces in the planar limit. The difference is effected by relocating the discontinuity of the assumed directional distribution of radiation intensity. The shift takes the discontinuity from precisely on the division between radially inward and radially outward, to just within the radially-outward directional half range. The method is tested on a variety of concentric spheres problems with and without internal heat sources, reproducing all the important features of the exact results.
Deconstructing Multiple Oppressions Among LGBT Older Adults

The purpose of this chapter is to interrogate oppression through an analysis of discourses related to lesbian, gay, bisexual, and transgender (LGBT) older adults. As part of our reflexive posture, we attend to the social constructions of meaning about age, ability, gender, race, and sex and their colossal impacts on LGBT older adults. We are mindful of the weight of oppression for LGBT older adults in general but in particular overlooked subgroups of this diverse population (e.g., people who are with low income, people of color, and people who are transgender and do not fit into the binary of woman or man, gay or straight). We confront multiple layers of discrimination by deconstructing cultural assumptions of normalcy (e.g., heteronormativity within the LGBT community) presented in visual form, verbal text, and within discourses.
Cluster Ion Reactions: Insights into Processes of Atmospheric Significance

Experimental results of ion cluster reactions withatmospherically relevant species are considered hereinto provide a unified overview of the current state ofunderstanding brought about through experimentalstudies of cluster ion reactions. This isaccomplished by first outlining the atmospheric issuesaddressed by cluster ion studies and then, summarizingthe results of numerous studies. The recent, as wellas previously published studies of cluster ionreactions, are considered in the context of gainingnew insights into the molecular details ofheterogeneous processes involving the interactions ofelectrolytes with cloud droplets, ice crystals andaerosol particles. In addition to elucidating themechanisms of these and other selected reactions andtransformations of atmospheric significance, thefindings of the uptake of acid molecules in waterclusters are shown to lead to the suggestion of a newmodel that accounts for the formation of reactioncenters involving charged sites at aqueous surfaces.
Coated bifunctional catalysts for NOx SCR with C3H6: Part II. In situ spectroscopic characterization

Abstract The effect of finely coating Cu-ZSM-5 with nanoparticles of ceria has been studied in situ by XANES, DRIFTS and TPR. The combination of these techniques reveals a lower temperature of reduction for both metals (Cu and Ce) in the bifunctional catalyst. Copper interacts with ceria nanocrystals at the oxide–zeolite interface and forms a localized phase comparable to doped ceria solid solutions commonly used as oxidation catalysts. As a result the catalyst is able to activate C 3 H 6 and form NO 2 at low temperatures. Analysis of the stability of adsorbed CO by DRIFTS suggests that the addition of water promotes the oxidation of Cu 1+ on the coated catalyst. In addition, TPD and TGA results, in combination with supplementary DRIFTS experiments, indicate that the ceria coating retains water at the interface during reaction conditions. The combination of these events yields relatively high C 3 H 6 -SCR activity at temperatures as low as 250 °C. It is believed that the affinity towards water and extended coverage of the coating also protects the zeolite against degradation by restricting the diffusion of water molecules into the zeolite pores.
Response of two species of cassia and Gliricidia sepium to vesicular‐arbuscular mycorrhizal infection

Abstract A pot experiment was conducted to evaluate the response to vesicular‐arbuscular mycorrhizal (VAM) infection of two species of Cassia and Gliricidia sepium in an oxisol with two levels of soil P. At P level optimum for VAM activity, comparable levels of VAM infection were observed on the roots of the test species. However, the species reacted differently to VAM infection. Hence, VAM inoculation significantly stimulated dry matter accumulation in C. spectabilis and G. sepium, but had no positive influence on this variable in C. reticulata. These differences were not explainable in terms of tissue P status, because P uptake was significantly enhanced by inoculation in all the species tested. At the higher soil P level, roots of all species were colonized by the inoculum, but colonization level in C. reticulata and G. sepium was reduced. Nevertheless, only C. spectabilis benefitted from the presence VAM endophytes at this level of soil P. The results underline the significance of ascertaining the myc...
The effects of emotional ambivalence on creativity

Emotional ambivalence, or the simultaneous experience of positive and negative emotions, is an underexplored emotional state in organizations. The results from two laboratory experiments demonstrat...
Protein crystallization by rational mutagenesis of surface residues: Lys to Ala mutations promote crystallization of RhoGDI.

Crystallization is a unique process that occurs at the expense of entropy, including the conformational entropy of surface residues, which become ordered in crystal lattices during formation of crystal contacts. It could therefore be argued that epitopes free of amino acids with high conformational entropy are more thermodynamically favorable for crystal formation. For a protein recalcitrant to crystallization, mutation of such surface amino acids to residues with no conformational entropy might lead to enhancement of crystallization. This paper reports the results of experiments with an important cytosolic regulator of GTPases, human RhoGDI, in which lysine residues were systematically mutated to alanines. Single and multiple mutations were introduced into two different variants of RhoGDI, NΔ23 and NΔ66, in which the first 23 and 66 residues, respectively, were removed by recombinant methods. In total, 13 single and multiple mutants were prepared and assessed for crystallization and all were shown to crystallize using the Hampton Research Crystal Screens I and II, in contrast to wild-type NΔ23 and NΔ66 RhoGDI which did not crystallize. Four crystal structures were solved (the triple mutants NΔ23:K135,138,141A and NΔ66:K135,138,141A, and two single mutants NΔ66:K113A and NΔ66:K141A) and in three cases the crystal contacts of the new lattices were found precisely at the sites of mutations. These results support the notion that it is, in principle, possible to rationally design mutations which systematically enhance proteins' ability to crystallize.
The influence of aging on androgen dynamics in the male rat

Abstract Androgen assimilation was investigated in a variety of accessory sex organs (seminal vesicles and anterior, dorsal, lateral, and ventral prostates) and in several nonaccessory sex organs in male Wistar rats. After administration of a pulse dose of [3H]testosterone in vivo to intact young (3–4 months old) rats, [3H]testosterone was the primary radioactive steroid recovered from most organs examined, except for the secondary sex glands where the reduced metabolites, [3H]5α-dihydrotestosterone (DHT) and [3H]5α-androstanediol(s), predominated. At longer postinjection times, [3H]DHT was preferentially retained in the accessory sex glands, presumably reflecting intracellular metabolism of [3H]testosterone to this compound and subsequent specific binding of [3H]DHT to receptor proteins. At the longest postinjection interval investigated, the ventral prostate retained greater concentrations of [3H]DHT than the lateral prostate which in turn had a higher [3H]DHT concentration than the seminal vesicles or anterior or dorsal prostates. The latter three glands retained approximately equal concentrations of [3H]DHT. Scatchard plot analyses of cytosol binding in 24-h castrates indicated that with one exception, the level of high affinity DHT binding sites was generally correlated with the retention of [3H]DHT in vivo in intact rats. Specifically, while the affinity for DHT binding in all accessory sex organs was the same, the number of high affinity binding sites per mg wet tissue weight was on the order of ventral prostate > anterior prostate ≥ seminal vesicles ≥ dorsal prostate > lateral prostate. Studies of the influence of aging to 22–26 months revealed no apparent differences in the affinity of the DHT receptor for its ligand in any of the accessory sex glands from 24-h castrates when the receptors were present in levels sufficiently high to quantify. The concentration of available DHT receptors with advancing age remained constant in the anterior and dorsal prostates, increased in the seminal vesicles, and declined in the ventral and lateral prostates. The decreases observed in the ventral prostate were only partial, but the receptors of the lateral prostate declined to nondetectable levels.
Weight gain from novel antipsychotic drugs: need for action.

Abstract Obesity is common in schizophrenia, and people with schizophrenia appear to be at increased risk for certain obesity-related conditions, such as type 2 diabetes and cardiovascular disease. Antipsychotic drugs, used chronically to control symptoms of schizophrenia, are associated with often-substantial weight gain, a side effect that is a special concern with the latest generation of highly effective “novel” agents. That the most effective (e.g., novel) antipsychotic medications lead to substantial weight gain presents the field with a critical public health problem. Although preliminary data have been reported regarding the beneficial use of behavior therapy programs for short-term weight control in patients with schizophrenia, the available data are quite limited, and there are no data regarding the long-term beneficial effects of these programs in this population. The obesity field recently has developed programs emphasizing “lifestyle changes” (e.g., diet, exercise, and problem-solving skills) to successfully manage weight in patients without schizophrenia. Such programs can be adapted for patients with schizophrenia through the use of highly structured and operationalized modules emphasizing medication compliance, social skills development, and participation in outpatient programs. Moreover, these programs can potentially be combined with the use of adjunctive pharmacotherapy to maximize and maintain weight loss. The field must solve the paradox that some of our most effective medications for schizophrenia produce substantial weight gain and its associated troubling health risks.
Controlling backward inference

Abstract Effective control of inference is a critical problem in artificial intelligence. Expert systems make use of powerful domain-dependent control information to beat the combinatorics of inference. However, it is not always feasible or convenient to provide all of the domain-dependent control that may be needed, especially for systems that must handle a wide variety of inference problems, or must function in a changing environment. In this paper, a domain-independent means of controlling inference is developed. The basic approach is to compute expected cost and probability of success for different backward inference strategies. This information is used to select between inference steps, and to compute the best order for processing conjunctions. The necessary expected cost and probability calculations rely on simple information about the contents of the problem solver's database, such as the number of facts of a given form, and the domain sizes for the predicates and relations involved.
Media coverage of environmental pollution in the People’s Republic of China: responsibility, cover-up and state control:

On 13 November 2005, an explosion rocked the Jilin Petrochemical Company, a subsidiary of the state-owned China National Petroleum Corporation (CNPC), spilling nearly 100 tons of benzene into the Songhua River. Six people were killed in the blast, and thousands of residents were forced to evacuate their homes. The explosion also resulted in an 80-kilometer slick of toxic benzene in the Songhua, which supplies the municipal water system of Harbin, a city of more than 5 million people in China’s northeastern region of Manchuria. Benzene is a clear, colorless liquid that is used in industrial solvents and for making plastics, rubber, resins, nylon and polyester. Acute exposure to high levels of benzene causes dizziness, headaches, elevated heart rate, and possibly death. Long-term exposure to benzene, a known carcinogen, has been linked with immunological defects, cancers such as leukemia, and toxic effects on the blood, liver, kidney, lungs, heart and brain (ATSDR [Agency for Toxic Substances and Disease Registry], 2007). The Chinese Ministry of Environmental Protection (MEP), which conducts airand waterquality monitoring, and sets national emissions standards, established a safety threshold of 5 micrograms of benzene per liter of drinking water (MEP, 1996); following the chemical plant explosion, benzene levels in the Songhua River exceeded that level by more than 100 times. Government authorities avoided notifying the public for more than a week, shutting down the entire municipal water system of Harbin for several days under the guise of conducting ‘routine repairs’. However, China Central Television (CCTV), which operates under state control but exercises some editorial autonomy, reported on the story immediately. Panicked residents,
Mapping Aβ amyloid fibril secondary structure using scanning proline mutagenesis

Although the amyloid fibrils formed from the Alzheimer's disease amyloid peptide Abeta are rich in cross-beta sheet, the peptide likely also exhibits turn and unstructured regions when it becomes incorporated into amyloid. We generated a series of single-proline replacement mutants of Abeta(1-40) and determined the thermodynamic stabilities of amyloid fibrils formed from these mutants to characterize the susceptibility of different residue positions of the Abeta sequence to proline substitution. The results suggest that the Abeta peptide, when engaged in the amyloid fibril, folds into a conformation containing three highly structured segments, consisting of contiguous sequence elements 15-21, 24-28, and 31-36, that are sensitive to proline replacement and likely to include the beta-sheet portions of the fibrils. Residues relatively insensitive to proline replacement fall into two groups: (a) residues 1-14 and 37-40 are likely to exist in relatively unstructured, flexible elements extruded from the beta-sheet-rich amyloid core; (b) residues 22, 23, 29 and 30 are likely to occupy turn positions between these three structured elements. Although destabilized, fibrils formed from Abeta(1-40) proline mutants are very similar in structure to wild-type fibrils, as indicated by hydrogen-deuterium exchange and other analysis. Interestingly, however, some proline mutations destabilize fibrils while at the same time increasing the number of amide protons protected from hydrogen exchange. This suggests that the stability of amyloid fibrils, rather than being driven exclusively by the formation of H-bonded beta-sheet, is achieved, as in globular proteins, through a balance of stabilizing and destabilizing forces. The proline scanning data are most compatible with a model for amyloid protofilament structure loosely resembling the parallel beta-helix folding motif, such that each Abeta(15-36) core region occupies a single layer of a prismatic, H-bonded stack of peptides.
Knowledge laundering: testimony and sensitive invariantism

The words 'taller than the average American male' express the same property at every context of use, but how tall something must be in order to have this property varies with the time and world of evaluation. In 1974, my father had this property, but now he does not, even though his own height has not changed. In the same way, sensitive invariantists claim, the word 'know' expresses the same relation at every context of use, but how good an epistemic position an agent must occupy in order to stand in this relation to a proposition depends on the agent's practical situation at the circumstances of evaluation. Thus it can be true that yesterday Sally knew that Sacramento is the capital of California, but today she does not, though her epistemic position has not changed. In this way sensitive invariantists can acknowledge a kind of variability in the epistemic standards required for knowing, without denying (as contextualists do) that 'know' expresses the same relation at every context of use.1 In this note, I will show that sensitive invariantism is incompatible with a widely held view about how knowledge is transmitted through testimony. I will not take a stand here on which of these views should be rejected.
Domain wall model for SMA characterization

We develop a model that quantifies constitutive nonlinearities and hysteresis inherent to ferroelastic compounds, with emphasis placed on shape memory alloys. We formulate the model in two steps. First, we use the Landau theory of phase transitions to characterize the effective Gibbs free energy for both single-crystal and polycrystalline ferroelastics. The resulting nonlinear equations model ideal material behavior in the absence of impurities. Second, we incorporate pinning losses to account for the energy required to move domain walls across material inclusions. We illustrate aspects of the model through comparison with experimental stress-strain data.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
First Wall Qualification Testing at SNL

The first wall of ITER will be a replaceable sandwich of beryllium tiles, water-cooled copper alloy, and a water-cooled stainless steel backing. The first wall will be subject to approximately 30,000 pulses of surface heating at levels of 0.2 - 0.5 MW/m2 and 5 - 10 W/cm3 of volumetric nuclear heating. At these low heating levels, the main failure mechanism is predicted to be fatigue, particularly at the interface between the copper alloy and beryllium tile. Six different party teams are proposing to produce the first wall for ITER To qualify the processes and materials for producing the first wall, small mock-ups will be subject to fatigue testing at Sandia National Laboratories' (SNL) Plasma Materials Test Facility and at a European Union test facility. We propose that the failure of a joining process is determined by an increase of surface temperature over nominal temperatures for a given surface heat flux. If the joint between a Be tile and Cu alloy degrades, the path from the heated surface to the coolant in the copper alloy increases, which should result in a higher surface temperature. This paper will document the test setup and preliminary analysis of the fatigue testing and failure criteria at SNL.
Lubricity of zinc oxide thin films: Study of deposition parameters and Si as an additive

Zinc oxide preferentially crystallizes into a wurzite structure and has a unique set of properties. There have been numerous studies on doped zinc oxide thin films as an optical coating or as a semiconductor material. However, very little work has been reported on its tribological properties. Recent reports from this laboratory revealed that ZnO has good potential for controlling friction and wear. ZnO has an open structure and favorable coordination number, which permits zinc to freely move to different positions in the crystal lattice and to accommodate external atoms as substitutes. The nature of the substitution and the concentration of Zn interstitials may be used to control tribological performance. In this work, thin films of zinc oxide were deposited by pulsed laser ablation while silicon was added simultaneously by magnetron sputtering. The effects of deposition geometry and oxygen partial pressure on stoichiometry and microstructure were evaluated. It was found that the angle of deposition and oxygen partial pressure control coating texture. Depositions normal to the sample surface, along with 10 mtorr of oxygen, produced strong (002) texture. These conditions were selected for Si-doping studies. The tribological characteristics of Si-doped coatings were evaluated at both room and high temperature. Addition of Si around 7–8% gave a coefficient of friction of about 0.2 at 300 °C, decreasing to 0.13 around 500 °C.
Methods for detecting barbiturate poisoning in a clinical laboratory

The detection limits for 23 barbiturates and the main metabolite of phenobarbital were determined in urine, using six different tests: a colorimetric test, TLC and four immunological tests. The precision, duration and costs of the tests were examined, in order to determine their suitability for a clinical laboratory.
Isolation, cell culture, and characterization of oviduct epithelial cells of the cow

This report describes an easy method of isolation and cell culture of the epithelial cells of cow oviduct. Incubation of cow oviduct with 0.1 mg/ml collagenase in the lumen for 90 minutes helped to dislodge large numbers of ciliated and secretory epithelial cells. The isolated cells, when seeded on plastic, proliferated very quickly and became confluent in 8–10 days in 35 mm Petri dishes. The isolated ciliated cells which attached to the plastic dish lost their cilia after 4–5 days in culture. The cultured epithelial cells were keretin positive. The isolated bovine oviduct epithelial cells, when cultured on plastic precoated with 10 mg/ml matrigel, organized themselves into hollow tubes or spheres with microvilli directed towards the lumen. The epithelial cells seeded on 2 mg/ml matrigel became subconfluent in 15–20 days after seeding. The histoarchitecture of the secretory cells growing in vitro on matrigel resembled that of intact oviduct secretory epithelial cells. Occasional ciliated cells containing large number of mitochondria were observed in the monolayer cultured on 2 mg/ml matrigel substratum but possessed few cilia. The oviduct epithelial cells cultured on 2 mg/ml matrigel incorporated 35S-methionine linearily into protein up to 8 hours in the presence of estradiol or progesterone. The fluorograph of the newly synthesized proteins indicated the presence of an additional 60 kd protein in the cell extract of epithelial cells incubated with estradiol. © 1995 Wiley-Liss, Inc.
Quantitative High - Resolution Gas Chromatography and High - Resolution Gas Chromatography/Mass Spectrometry Analyses of Carbonaceous Fine Aerosol Particles

Methods have been developed for the quantification of low-microgram levels of the extractable organic matter contained in the atmospheric fine aerosol fraction. Extract quantification is accomplished by computer-assisted high-resolution gas chromatography (HRGC) used in conjunction with a procedural recovery mixture containing perdeuterated compounds of differing polarity and molecular weight. Recovery data for these species indicate that relative volatility rather than functional group classification is the primary factor affecting overall recovery. Routine quality control analysis is performed on a per-sample basis by high-resolution gas chromatography/mass spectrometry (HRGC/MS) for confirmation of the standard components and for identification of procedural contaminants. By the way of illustration, fine aerosol samples have been analyzed from Anaheim. California. The absolute solvent extract yields range from 49 to 346μg of organic carbon, and demonstrate a seasonal variation with winter maximum and summer minimum concentrations.
Rad54 protein possesses chromatin-remodeling activity stimulated by the Rad51–ssDNA nucleoprotein filament

In Saccharomyces cerevisiae, the Rad54 protein participates in the recombinational repair of double-strand DNA breaks together with the Rad51, Rad52, Rad55 and Rad57 proteins. In vitro, Rad54 interacts with Rad51 and stimulates DNA strand exchange promoted by Rad51 protein. Rad54 is a SWI2/SNF2-related protein that possesses double-stranded DNA-dependent ATPase activity and changes DNA topology in an ATP hydrolysis-dependent manner. Here we show that Rad54 catalyzes bidirectional nucleosome redistribution by sliding nucleosomes along DNA. Nucleosome redistribution is greatly stimulated by the Rad51 nucleoprotein filament but does not require the presence of homologous single-stranded DNA within the filament. On the basis of these data, we propose that Rad54 facilitates chromatin remodeling and, perhaps more generally, protein clearing at the homology search step of genetic recombination.
Improving the continuous execution of reactive LTL-based controllers

Recently, formal methods have been used to transform high-level robot tasks into correct-by-construction controllers. While correctness is guaranteed, these inherently discrete methods often lead to behaviors that are not optimal in the continuous sense, i.e. they induce robot paths that are significantly suboptimal. This paper proposes an algorithm for dynamically reordering the robot goals and connecting them via the shortest path with respect to a given continuous metric. The generated robot trajectories are close-to-optimal while satisfying the task specification in a dynamic environment. This method is implemented and simulation results are shown.
The Structure of Attitudes Toward Groups: A Comparison of Experts and Novices

The study of mass opinion has recently focused increased attention on political sophistication and attitudes toward groups. Although the two topics are not directly related, they share a common concern: how does the mass public manage to form opinions about political issues given its well-established lack of a coherent political ideology. Groups are important symbols that structure political reasoning; but, it is not clear that this structure is the same for people with different levels of political awareness. On the one hand, the sophistication hypothesis has found low levels of political sophistication associated with poorly organized issue attitudes and ideological naivete. On the other hand, research supporting the group hypothesis suggests that groups may provide even the least politically sophisticated with a coherent view of the political world. To test these ideas we draw upon data from the 1980 and 1984 studies of delegates to the Democratic and Republican national conventions and the National Election Studies of the same year. We find, in agreement with the preponderance of evidence in the literature on political sophistication, that the structure of attitudes toward groups becomes more ideological as the level of political sophistication increases. Furthermore, we argue that with decreasing levels of political sophistication comes a greater reliance on emotion as a guide to the political world.
The Australian Childhood Dementia Study

Objectives To estimate the prevalence of childhood dementia, identify aetiological factors, and provide a brief survey of the psychosocial impact of childhood dementia. Method The Australian Paediatric Surveillance Unit (APSU) was used to identify children with dementia. A total of 224 cases were notified about the dementia study and 141 (63 %) questionnaires were completed and returned. Ascertainment was restricted to those most likely to have progressive neurocognitive decline because of practitioner bias against reporting non-progressive cases as dementia. Results Eighty children with dementia were identified. The estimated prevalence for dementia in childhood in Australian was 5.6/100,000. Thirteen cases (16 %) were notified before the age of two years. Seventeen (21 %) children were reported to have uncertain or unknown aetiology. Impact upon day to day family functioning was reported by clinicians to be ‘marked’ or ‘extreme’ in 50 (63 %) families. Only four (6 %) clinicians judged present services to be ‘very adequate’, while 16 (20 %) clinicians judged current psychological support for the needs of the family to be ‘very’ or ‘moderately inadequate’. Dementia as an overarching diagnostic concept offers integrative possibilities for research, management and service planning and provision. Childhood disintegrative disorder [1] as a concept is criticised.
Sexually transmitted infection control with sex workers: regular screening and presumptive treatment augment efforts to reduce risk and vulnerability.

Abstract Sex workers have high rates of sexually transmitted infections (STIs), many of them easily curable with antibiotics. STIs as co-factors and frequent unprotected exposure put sex workers at high risk of acquiring HIV and transmitting STIs and HIV to clients and other partners. Eliminating STIs reduces the efficiency of HIV transmission in the highest-risk commercial sex contacts—those where condoms are not used. This paper reviews two STI treatment strategies that have proven effective with female sex workers and their clients. 1) Clinical services with regular screening have reported increases in condom use and reductions in STI and HIV prevalence. Such services include a strong peer education and empowerment component, emphasize consistent condom use, provide effective treatment for both symptomatic and asymptomatic STIs, and begin to address larger social, economic and human rights issues that increase vulnerability and risk. 2) Presumptive treatment of sex workers, a form of epidemiologic treatment, can be an effective short-term measure to rapidly reduce STI rates. Once prevalence rates are brought down, however, other longer-term strategies are required. Effective preventive and curative STI services for sex workers are key to the control of sexually transmitted infections, including HIV, and are highly synergistic with other HIV prevention efforts.
Vertical winds in the midlatitude thermosphere from Fabry-Perot Interferometer measurements

Abstract Monostatic and bistatic measurements of thermospheric winds have been made with Fabry-Perot Interferometers at the Millstone Hill and Laurel Ridge Observatories. Synchronized observing sequences have been chosen to enable the determination of vertical winds from the measurements. The vertical winds are found to be significant on some nights with velocities of tens of m/s. For geomagnetically quiet nights, the averaged values for eight samples in the July–October 1992 period show little variation during the night, averaging ∼10 m/s downward. The average for three geomagnetically disturbed nights oscillates from a downward maximum of ∼50 m/s at ∼02 UT to an upward maximum of ∼20 m/s at ∼07 UT. Temporal variations in the vertical motions suggest oscillatory behavior with periods of ∼0.7, ∼1.8 and ∼3.4 h, respectively, on three quiet nights, possibly associated with gravity wave or tidal-harmonic effects.
Ligation of EcoRI endonuclease-generated DNA fragments into linear and circular structures.

Abstract Double-stranded DNA fragments terminated at their 5′-ends by the singlestranded sequence pA-A-T-T-, generated by digestion of DNA with Eco RI restriction endonuclease, were ligated with Escherichia coli polynucleotide ligase under various conditions of temperature, concentration and time. The linear and circular products of ligation were separated by electrophoresis in agarose gel and quantitated by densitometry. The rate of ligation of ( Eco RI-cleaved) simian virus (SV40) DNA at a concentration of 100 μg/ml increased from 0 °C to 5 °C to 10 °C (6-fold increase overall); raising the temperature to 15 °C did not further increase the rate of ligation. At the appropriate DNA concentrations, the predominant products of ligation are either linear concatemers that are integral multimers of the starting DNA fragment, or covalently closed circular structures of the monomeric DNA fragment. Ligating a mixture of two different length DNA fragments gives rise to all of the possible expected recombinant molecules. Linear or circular products of ligation were predicted by consideration of the total concentration of DNA termini, i , and the local concentration of one terminus in the neighborhood of the other on the same DNA molecule, j . The parameter j is a function of the length of a DNA molecule, providing this length is greater than the random coil segment of DNA. Experimentally it was found that circular structures are formed in significant amounts only under conditions when the value of j is several times greater than that of i . When j = i , equal amounts of linear and circular products would be expected, but most of the molecules were ligated into linear concatemers. No circular structure of a DNA fragment whose contour length l (6 × 10 −2 μm) is smaller than the random coil segment value b (7·17 × 10 −2 μm) was observed, while circular structures of the dimer of the same molecule (12 × 10 −2 μm) were detected.