cssi/SciSciGPT-SciSciNet huggingface dataset:
Durable and High-Power Iron-Based Cathodes in Competition with Platinum for Proton-Exchange Membrane Fuel Cells

Atomically dispersed and nitrogen-coordinated single iron sites (FeN4) embedded in carbon (Fe-N-C) catalysts are the most promising platinum group metal (PGM)-free catalysts. However, they have yet to match their Pt counterparts for oxygen reduction reaction (ORR) activity and stability in proton exchange membrane fuel cells (PEMFCs). Here, we developed viable Fe-N-C catalysts, which, for the first time, demonstrated competitive activity to that of Pt/C catalysts and dramatically enhanced stability and durability under practical PEMFC operating conditions. The most active Fe-N-C catalyst achieved a record half-wave potential (E1/2 = 0.915 V vs. RHE at 0.6 mgcatcm-2) and an ORR mass activity of 10.5 mA mgcat at 0.9 V in (RDE) tests, exceeding a Pt/C baseline catalyst (60 µgPt cm-2) by 40 mV in acidic electrolytes. This compelling activity of the Fe-N-C catalyst in aqueous acids on rotating disk electrode (RDE) was successfully transferred to a fuel cell membrane electrode assemblies (MEAs), generating an initial current density of 44.2 mA cm-2 exceeding the U.S. DOE 2025 target (i.e., 44 mA cm-2) at 0.9 VIR-free under O2. Under practical hydrogen-air conditions, record 151 mA cm-2 at 0.8 V and peak power density of 601 mW cm-2 were achieved. Importantly, we discovered that depositing nitrogen-carbon species on the catalyst surface via chemical vapor deposition (CVD) dramatically enhanced catalyst stability, evidenced by performance durability after accelerated stress tests (30 000 square-wave voltage cycles under H2/air) and long-term steady-state life tests (> 300 hours at 0.67 V). Innovative identical location-scanning transmission electron microscopy (IL-STEM) experiments confirmed that the CVD process leads to deposition of nitrogen-doped carbon onto the catalyst surfaces. Along with theoretical modeling, a reconstruction of the carbon structure adjacent to FeN4 sites leads to increased robustness against demetallation and carbon oxidation. This work opens new avenues for developing earth-abundant iron-based catalysts with extraordinary activity and stability, thus competing with Pt and addressing the cost barrier of current PEMFCs.
Understanding patient preference in prosthetic ankle stiffness.

Background User preference has the potential to facilitate the design, control, and prescription of prostheses, but we do not yet understand which physiological factors drive preference, or if preference is associated with clinical benefits. Methods Subjects with unilateral below-knee amputation walked on a custom variable-stiffness prosthetic ankle and manipulated a dial to determine their preferred prosthetic ankle stiffness at three walking speeds. We evaluated anthropomorphic, metabolic, biomechanical, and performance-based descriptors at stiffness levels surrounding each subject's preferred stiffness. Results Subjects preferred lower stiffness values at their self-selected treadmill walking speed, and elected to walk faster overground with ankle stiffness at or above their preferred stiffness. Preferred stiffness maximized the kinematic symmetry between prosthetic and unaffected joints, but was not significantly correlated with body mass or metabolic rate. Conclusion These results imply that some physiological factors are weighted more heavily when determining preferred stiffness, and that preference may be associated with clinically relevant improvements in gait.
A Model of the Flow of Goods through a Market Center

Several archaeologists (Binford 1977; Goodyear, Raab and Klinger 1978) have recently called for the creation of "middle range theory" in archaeology. By this term they mean the establishment of a body of theory which will help bridge the interpretive gap between static archaeological facts and the dynamic past phenomena responsible for them. This body of theory would encompass such considerations as natural and cultural formation processes (Schiffer 1976; Sullivan 1978). In response to this exhortation I offer the following discussion and model of the flow of goods through a market center.
Electron interaction effect on the spin diffusion and transport in half metallic magnets

Abstract For half metallic magnets, spin fluctuation is the same as charge fluctuation. The length scale is controlled by electron–electron interaction and is of the order of the screening length, typically of the order of an Angstrom whereas the ordinary spin diffusion length is of the order of 100 A or more. We examine the eigenstates for charge and spin transport for systems close to half-metallicity. Due to the electron–electron interaction, the decay length of the eigenstate that corresponds to the longitudinal spin diffusion length is much reduced, consistent with recent experimental results. We explore the consequence of this. We find that there are two parameters that characterize half-metallicity and illustrate our results numerically with a simple model.
Using Footwarmers in Offices for Thermal Comfort and Energy Savings

Abstract An office equipped with personal footwarmers was maintained at cooler-than-normal indoor temperatures in the winter, producing great energy savings. The occupants’ thermal comfort was not affected. The footwarmers provide individual heating control over a segment of the body that most strongly influences comfort perception when one is cool overall. If cooler ambient indoor temperatures could be made comfortable, savings in central heating energy would be possible. During a six-month winter period in Berkeley California, knowledge workers with low-energy footwarmers experienced a lowering of room heating set point from 21.1 °C (70 °F) to 18.9 °C (66 °F). Surveys showed equal thermal comfort in the original ‘higher heating setpoint no-footwarmer’ condition and the ‘lower heating set point plus occupant-controllable footwarmer’ condition. Heating energy was closely monitored throughout. It dropped 38–75% depending on the setpoint reduction and outdoor conditions. The added plug load energy from the low-energy footwarmers was much less than the central heating energy saved by lowering the heating set point (3–21 W vs 500–700 W average power per occupant during occupied hours). A few subjects had ergonomic issues with the particular footwarmers used, so usage was not universal. Additional foot- and leg-warmer design options would help.
High prevalence of bilateral varicoceles confirmed with ultrasonography.

Objective: To determine the incidence ofbilateral varicoceles in men presenting to asingle infertility clinic.Subjects and methods: From March 1999 toMarch 2000, 60 men presenting with an inabilityto initiate pregnancy (consecutive andunselected), were determined by clinical examto have varicoceles. These men were sent forcolor Doppler ultrasound to evaluate theincidence of varicocele bilaterality. Two menwith a solitary testis were excluded from thestudy.Results: Of the 58 men, 45 (77.5%) hadultrasound verified bilateral varicoceles. Inthe 13 remaining patients, 8 (13.8%) had aunilateral left varicocele, 4 (6.9%) had novaricoceles demonstrated by ultrasound, and asingle patient (1.7%) was reported to have aunilateral right varicocele.Conclusions: Routine scrotal ultrasoundprovides valuable information in the diagnosticevaluation of infertile men. Based onadvancements in diagnostic techniques,investigators have recently observed that theincidence of bilateral varicoceles to besignificantly greater than the previouslyreported. Our study demonstrated theincidence of bilaterality in infertile men tobe a substantial 77.5%. An overlooked rightvaricocele (whether subclinical or not) may bedetrimental to future fertility and needsfurther investigation.
Development of the virtual-human Santos®

This paper presents the background and history of the virtual human Santos™ developed by the Virtual Soldier Research (VSR) Program at The University of Iowa. The early virtual human environment was called Mira™. This 15-degree-of-freedom (DOF) upper-body model with posture and motion prediction was funded by John Deere Inc. and US Army TACOM Automotive Research Center. In 2003 US Army TACOM began funding VSR to develop a new generation of virtual humans called Santos (109 DOFs), which was to be another generation of Mira. Later on, Caterpillar Inc., Honda R&D North Americas, Natick Soldier System Center, and USCAR (GM, Ford, and Chrysler) joined the VSR partnership. The objective is to develop a new generation of digital humans comprising realistic human models including anatomy, biomechanics, physiology, and intelligence in real time, and to test digital mockups of products and systems before they are built, thus reducing the significant costs and time associated with making prototypes. The philosophy is based on a novel optimization-based approach for empowering these digital humans to perform, un-aided, in a physics-based world. The research thrusts include the following areas: (1) predictive dynamics, (2) modeling of cloth, (3) hand model, (4) intuitive interface, (5) motion capture, (6) muscle and physiology modeling, (7) posture and motion prediction, (8) spine modeling, and (9) real-time simulation and virtual reality (VR). Currently, the capabilities of Santos include whole-body posture prediction, advanced inverse kinematics, reach envelope analysis, workspace zone differentiation, muscle force and stress analysis, muscle fatigue prediction, simulation of walking and running, dynamic motion prediction, physiologic assessment, a user-friendly interface, a hand model and grasping capability, clothing modeling, thermo discomfort assessment, muscle wrapping and sliding, whole-body vibration analysis, and collision avoidance.
Chitin, Cholera, and Competence

Vibrio cholerae , a human pathogen, inhabits aquatic environments and is often associated with chitin-containing organisms. In their Perspective, [Bartlett and Azam][1] discuss the findings of [ Meibom et al .][2] in the same issue of chitin-mediated natural DNA transformation in V. cholerae . This finding opens a new window for understanding conditions that influence the evolution of this bacterium in aquatic habitats. [1]: http://www.sciencemag.org/cgi/content/full/310/5755/1775 [2]: http://www.sciencemag.org/cgi/content/full/310/5755/1824
Chemiion evolution in motor vehicle exhaust: Further evidence of its role in nanoparticle formation

[1] The evolution of engine-generated chemiions in a vehicle tailpipe or in a sampling transfer line is studied and the key parameters controlling chemiion concentration at the exit plane are investigated. We find that the observed higher number concentration but smaller size of nuclei mode particles associated with shorter transfer line residence time, enhanced nanoparticle emission associated with reduced soot emission, and increase in the number concentration but decrease in the size of nuclei mode particles associated with increasing traffic speed, can all be consistently explained by the reduced loss of ions in the transfer line or tailpipe. This provides further evidence that engine-generated chemiions play a key role in the formation of the nanoparticles in motor vehicle exhaust.
Er-Doped GaN and InxGa1-xN for Optical Communications

Considerable research effort has been devoted recently to the incorporation of RE ions, in particular Er3+, into wide bandgap III-nitride semiconductors. Significant progress has been achieved in terms of material growth and the understanding of fundamental optical properties of GaN:Er using photoluminescence (PL), photoluminescence excitation (PLE), and electroluminescence (EL) spectroscopies. Initially, poor crystalline quality of doped material resulted in very poor emission efficiency in the visible and infrared regions. Several growth techniques are now available to grow Er-doped GaN with reasonable crystalline quality and significantly improved optical emission at 1.54 4m has been demonstrated. In this chapter, we summarize major research on Er-doped GaN grown by different techniques. Very recent progress on Er-doped InGaN alloys, in particular those grown by metal organic chemical vapor deposition (MOCVD) in the authors’ laboratory, is reviewed. Electrical and optical properties are described as well as preliminary demonstrations of emitter and optical waveguide amplifiers operating in a 1.54 4m communication window. Perspectives and future challenges in material issues, design and fabrication of novel photonic devices of Erdoped nitride semiconductors for applications in optical communications are discussed.
A hybrid maximum likelihood-least squares reconstruction algorithm for emission computed tomography

A novel efficient hybrid maximum-likelihood/weighted least squares (ML/WLS) reconstruction algorithm for emission computed tomography is presented. The ML/WLS algorithm constructs optimized linear combinations of prior and current iterative image and projection estimates using a weighted least squares objective function. The optimized projections are backprojected with a maximum likelihood-expectation maximization (ML-EM) procedure. The ML/WLS method, including attenuation compensation, was used to reconstruct experimental single-photon emission computed tomography projection data obtained from a Hoffman brain phantom using the emission-transmission computed tomography system at the University of California, San Francisco. Results indicate that the ML/WLS procedure generates images qualitatively similar to those reconstructed with a conventional ML-EM algorithm, with significantly fewer iterations. >
User-aided reader revocation in PKI-based RFID systems

Recent emergence of RFID tags capable of performing public key operations motivates new RFID applications, including electronic travel documents, identification cards and payment instruments. In this context, public key certificates form the cornerstone of the overall system security. In this paper, we argue that one of the prominent challenges is how to handle revocation and expiration checking of RFID reader certificates. This is an important issue considering that these high-end RFID tags are geared for applications such as e-documents and contactless payment instruments. Furthermore, the problem is unique to public key-based RFID systems, since a passive RFID tag has no clock and thus cannot use time-based off-line methods.In this paper, we address the problem of reader certificate expiration and revocation in PKI-based RFID systems. We begin by observing an important distinguishing feature of personal RFID tags used in authentication, access control or payment applications --the involvement of a human user. We take advantage of the user's awareness and presence to construct a simple, efficient, secure and most importantly feasible solution. We evaluate the usability and practical security of our solution via user studies and discuss its feasibility.
Self-Correction Strategies for Frequency Domain Ringdown Analysis

This paper introduces a set of self-correction strategies for improved oscillation modal analysis of ring down responses from synchrophasors in frequency domain analysis. It is shown that the modal estimates of frequency, damping ratio and mode shape using the improved frequency domain algorithms of the paper match well with other time-domain algorithms while preserving their inherent advantages of superior noise performance and computational speed. The new algorithms of the paper are especially suited for simultaneous ring down oscillation analysis of large number of Phasor Measurement Unit (PMU) measurements efficiently.
Testing a Typology of Police Performance Measures: An Empirical Study of Police Services:

This research tests a typology used to classify performance measures used in local police departments. This typology classifies performance measures into three categories or domains: objective output measures, objective outcome measures, and subjective outcome measures. Using survey data, the authors test the hypothesis that public officials' preferences of police performance measures can be measured by this three-domain typology and that their preferences can be grouped as output oriented, objective outcome oriented, or subjective outcome oriented. The results indicate that local officials' preferences for police performance measures can be represented with this three-part typology.
Best viewpoints for active vision classification and pose estimation

We advance new active computer vision algorithms that classify objects and estimate their pose from intensity images. Our algorithms automatically reposition the sensor if the class or pose of an object is ambiguous in a given image and incorporate data from multiple object views in determining the final object classification. A feature space trajectory (FST) in a global eigenfeature space is used to represent 3-D distorted views of an object. Assuming that an observed feature vector consists of Gaussian noise added to a point on the FST, we derive a probability density function (PDF) for the observation conditioned on the class and pose of the object. Bayesian estimation and hypothesis testing theory are then used to derive approximations to the maximum a posteriori probability pose estimate and the minimum probability of error classifier. New confidence measures for the class and pose estimates, derived using Bayes theory, determine when additional observations are required as well as where the sensor should be positioned to provide the most useful information.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Glutamate affects dendritic morphology of neurons grown on compliant substrates.

Brain stiffness changes in response to injury or disease. Similarly, as a secondary consequence, glutamate is released from neurons and astroglia. Two types of glutamate receptors, N-methyl-D-aspartate (NMDA) and α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, sense mechanotransduction, leading to downstream signaling in neurons. Recently, our group reported that these two receptors affect dendrite morphology in hippocampal neurons grown on compliant substrates. Blocking receptor activity has distinct effects on dendrites, depending on whether neurons are grown on soft or stiff gels. In the current study, we examine whether exposure to glutamate itself alters stiffness-mediated changes to dendrites in hippocampal neurons. We find that glutamate augments changes seen when neurons are grown on soft gels of 300 or 600 Pa, but in contrast, glutamate attenuates changes seen when neurons are grown on stiff gels of 3000 Pa. These results suggest that there is interplay between mechanosensing and glutamate receptor activation in determining dendrite morphology in neurons.
Phase I/II trial of intravesical methotrexate for superficial bladder tumors

Twenty-one patients with superficial transitional cell carcinoma of the bladder received a total of 121 doses of intravesical methotrexate (MTX) at 11 different concentrations of drug, ranging from 40 mg/m2 (mean concentration of 2.9×10-3 M) to 500 mg/m2 (4.9×10-2 M). Biochemical evidence of absorption was minimal in all cases. The maximum serum level was observed within 0.5–2 h in all patients and ranged from 1.8×10-8 M to 5.0×10-7 M. By 24 h the serum levels were negligible and ranged from 5.5×10-9 M (the lowest limit detectable by the assay) to 4.4×10-8 M in the patient who received the highest dosage of 500 mg/m2. Biologic evidence of absorption was minimal. Myelosuppression, mucositis, and nausea were not observed. Eighteen patients received six consecutive weekly doses ranging from 40 to 500 mg/m2. All patients had repeat cytoscopy performed within 2–4 weeks after six consecutive doses to evaluate local toxicity and efficacy. Flow cytometry was performed on the bladder washings of 22 patients, illustrating the use of flow cytometry, in conjunction with conventional cytology, as an additional means of objectively quantifying results. Despite MTX's established activity in systemic treatment of advanced bladder carcinoma, this study failed to demonstrate any clinical response to intravesically administered MTX, in doses of up to 500 mg/m2, and in concentrations of up to 4.9×10-2 M.
Persons with traumatic brain injuries and their families: living arrangements and well-being post injury

This article discusses an empirical study of 66 single, adult survivors of moderate to severe traumatic brain injury (TBI) who were either living alone or living with their parents. The researchers determined perceived levels of stress, life satisfaction, family satisfaction, and community integration within the two groups. Survivors, who were typically ten years or more post injury, and selected family members, responded to structured telephone interviews and standardized questionnaires. The findings of the study and their implications point to a need for practice interventions that will reestablish life cycle trajectories and meet developmental needs, as well as reintegrate affected individuals and their families into larger social systems.
The precautionary principle and democratizing expertise: A US perspective

Democratizing expertise carries many implications for application of the precautionary principle. It can extend the amount and types of information incorporated into decisions, empower citizens, and ensure that experts alone are not charged with making value-laden decisions. It can also expose uncertainties in science and decision-making, and bring forth unrecognized alternative solutions to problems. In this article, we outline the implications of democratizing expertise on implementation of the precautionary principle in a US context, as well as barriers and opportunities. We argue that initiatives to democratize expertise and implement precaution in the United States will occur first at the local and regional level as a result of grassroots momentum for change. Copyright , Beech Tree Publishing.
Shape optimization analysis: first- and second-order necessary conditions

In this paper, first- and second-order necessary conditions for optimality are studied for a domain optimization problem. The optimization problem considered is the minimization of an objective function defined on the domain boundary through the solution of a boundary value problem. In order to derive the first and second variations of the objective function due to boundary variation, the first and second variations of the solution of the boundary value problem are calculated using a perturbation technique. An iterative shape optimization algorithm for potential flow problems in R2 with Dirichlet boundary conditions is presented. In the algorithm a boundary element method (BEM) is employed to solve the Laplace equation numerically. The validity and accuracy of the algorithm have been verified on a problem where the final solution is known. Finally, the problem of designing a 90° bend for two-dimensional potential flow is solved.
Isolation of an egg-laying hormone-binding protein from the gonad of Aplysia californica and its localization in oocytes.

A protein solubilized from a membrane preparation of the gonad of Aplysia californica has been isolated by affinity chromatography, using bag cell egg-laying hormone (ELH) as the bound ligand, and partially purified and characterized by gel electrophoresis. The protein has an apparent molecular weight of 52 kDa and consists of two disulfide-linked subunits of about 30 kDa each. The protein is glycosylated and has an acidic pI. Approximately 10–15 μg of this protein can be isolated from a single ovotestis, representing less than 1% of the total protein in the gonad; but the protein could not be detected in buccal mass or body wall, tissues which do not have apparent response to ELH. Antibodies generated against this ELH-binding protein (ELHBP) were used to localize sites in the ovotestis which might contain this molecule and thus represent targets for egg-laying hormone. Immunocytochemical results indicate that the oocytes are a rich source of this protein, since their cytoplasm was the only detectable site of immunoreactivity. Whether this binding protein represents an egg-laying hormone receptor is uncertain, but its prevalence in oocytes suggests that ELH plays a signaling role on these gametes.
Flow structure on diamond and lambda planforms : Trailing-edge region

The instantaneous and averaged flow structure on diamond and lambda planforms is characterized by using a technique of high-image-density particle image velocimetry. Emphasis is on the structure in the trailing-edge region, over a range of angle of attack. Elongated layers of vorticity in the crossflow plane exhibit well-defined mean (time-averaged) and instantaneous concentrations of vorticity. These features are interpreted in conjunction with patterns of streamline topology, as well as images of rms velocity fluctuation and velocity spectra obtained from space-time imaging.
Brief paper: Sliding mode control of a class of underactuated systems

A sliding mode control approach is proposed to stabilize a class of underactuated systems which are in cascaded form. This class of underactuated systems can represent many real applications after transformations. In the controller design, the sliding surface is designed to stabilize the indirectly controlled modes. Its insensitivity to the model errors, parametric uncertainties and other disturbances and its ability to globally stabilize the system are two advantages of the sliding mode controller.
Infant feeding responsiveness: a conceptual analysis.

Infant feeding responsiveness: a conceptual analysis Background. The phenomenon of infant responsiveness to the caregiver during feeding interactions has been of interest to researchers for many years, because of its associated implications for child growth and development. Although many studies have examined feeding responsiveness in caregiver–infant dyads, it is infrequently and inconsistently defined in the literature. Specific Aims. The purpose of this paper is to clarify the concept of infant feeding responsiveness through the provision of a working definition of the concept for further study and usage. Methods. Medline, CINAHL, and PschInfo databases from the year 1970 to the present were searched for English articles containing the keywords ‘infant’, ‘feeding’, ‘responsiveness’, ‘synchrony’, and/or ‘interaction’. Articles were selected for inclusion according to whether or not the phenomenon of infant feeding responsiveness was defined or assessed. Walker and Avant’s (1995) method for concept analysis was employed for the development of defining attributes, case examples, antecedents, and consequences for further clarification of the concept of infant feeding responsiveness. Findings. Infant feeding responsiveness was defined as the manifestation of physiologically influenced visual, expressive, vocal and motor reactive behaviours expressed by an infant in reaction to a caregiver’s feeding attempts, indicating a readiness to feed. Conclusions. Implications for nursing are explored as well as the need for refinement of measures of this concept.
Design and performance evaluation of a near-infrared Fourier transform spectrometer

A modular Fourier transform spectrometer for the near infrared (NIR) wavelength region was designed and built. The work was motivated by the need for a versatile, economical and a dedicated instrument for research in the area of noninvasive diagnostics. The spectrometer uses a thermo- electrically cooled InGaAs detector for maximum sensitivity and CaF2 lenses for maximum transmission in the NIR region. Great attention was put to ensure that each element was designed and/or chosen to provide maximum sensitivity in the NIR region. The first part of the paper discusses the spectrometer design procedures, which include the design of detector optics, collimating optics, interferometer optics as well as the signal processing electronics and motion control. The second part focuses on performance evaluation and quantification of errors including detector noise, digitization noise and sampling errors. For measurements of water absorption, spectral signal-to-noise ration of ~ 50000 was demonstrated over 150cm-1 wavenumber range. Instrumentation sensitivity was found to be limited by interferogram data sampling noise.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Wavefront Transfer for On-Shot Focal Spot Characterization at the 400 TW SCARLET Laser

Ohio State’s 400 TW SCARLET laser can deliver intensities of 1021 W/cm2. We present work to establish a phase relationship between wavefronts far from target and those near target. The calculated wavefront predicts the on-target focal spot on each shot.
Apolipoprotein A-I Is Necessary for thein Vivo Formation of High Density Lipoprotein Competent for Scavenger Receptor BI-mediated Cholesteryl Ester-selective Uptake

The severe depletion of cholesteryl ester (CE) in steroidogenic cells of apoA-I−/− mice suggests that apolipoprotein (apo) A-I plays a specific role in the high density lipoprotein (HDL) CE-selective uptake process mediated by scavenger receptor BI (SR-BI) in vivo. The nature of this role, however, is unclear because a variety of apolipoproteins bind to SR-BI expressed in transfected cells. In this study the role of apoA-I in SR-BI-mediated HDL CE-selective uptake was tested via analyses of the biochemical properties ofapoA-I−/− HDL and its interaction with SR-BI on adrenocortical cells, hepatoma cells, and cells expressing a transfected SR-BI. apoA-I−/− HDL are large heterogeneous particles with a core consisting predominantly of CE and a surface enriched in phospholipid, free cholesterol, apoA-II, and apoE. Functional analysis showed apoA-I−/− HDL to bind to SR-BI with the same or higher affinity as compared withapoA-I+/+ HDL, butapoA-I−/− HDL showed a 2–3-fold decrease in the V max for CE transfer from the HDL particle to adrenal cells. These results indicate that the absence of apoA-I results in HDL particles with a reduced capacity for SR-BI-mediated CE-selective uptake. The reduced V maxillustrates that HDL properties necessary for binding to SR-BI are distinct from those properties necessary for the transfer of HDL CE from the core of the HDL particle to the plasma membrane. The reduced V max for HDL CE-selective uptake likely contributes to the severe reduction in CE accumulation in steroidogenic cells of apoA-I−/− mice.
Development of Laser Beam Transmission Strategies for Future Ground-to-Space Optical Communications

Optical communications is a key technology to meet the bandwidth expansion required in the global information grid. High bandwidth bi-directional links between sub-orbital platforms and ground and space terminals can provide a seamless interconnectivity for rapid return of critical data to analysts. The JPL Optical Communications Telescope Laboratory (OCTL) is located in Wrightwood California at an altitude of 2.2.km. This 200 sq-m facility houses a state-of- the-art 1-m telescope and is used to develop operational strategies for ground-to-space laser beam propagation that include safe beam transmission through navigable air space, adaptive optics correction and multi-beam scintillation mitigation, and line of sight optical attenuation monitoring. JPL has received authorization from international satellite owners to transmit laser beams to more than twenty retro-reflecting satellites. This paper presents recent progress in the development of these operational strategies tested by narrow laser beam transmissions from the OCTL to retro-reflecting satellites. We present experimental results and compare our measurements with predicted performance for a variety of atmospheric conditions.
Guest Editorial: Optical Computing

John Caulfield as editor of this journal has made a commitment to devote each January's special issue of Optical Engineering to the topic of optical computing. I belieive that this annual issue can become a significant factor in the advancement of the field.
The Effects of Aging and Hearing Loss on Distortion Product Otoacoustic Emissions

Abstract Objective We sought to demonstrate the rate of change in distortion product otoacoustic emission (DPOE) amplitude with age in relation to hearing loss in an unselected adult population. Study design and setting We conducted a cross-sectional observation study involving the Framingham Offspring Cohort. Age changes in DPOE amplitude for frequencies of f2 from 1 to 8 kHz adjusted for pure-tone threshold level were assessed by multivariate linear regression. Results The women showed a mean hearing threshold-adjusted loss in high-frequency DPOE amplitude of 0.6, 2.1, 2.6, and 1.1 dB/per decade at the f2 frequencies of 1, 2, 4, and 8 kHz, respectively. In contrast, the men showed no effect of age on the DPOE amplitude independent of hearing loss. Emissions were reduced or absent in the noise notch frequencies. The rate of change with age in DPOE amplitude was significantly less than the rate of change in pure-tone thresholds in both the men and the women. Conclusion Women lose DPOE amplitude from both age and hearing threshold loss. Men lose more DPOE amplitude than do women, and the loss is proportional to the degree of loss of hearing threshold sensitivity. The differential effect whereby age-related hearing loss affects thresholds more than emissions suggests that strial atrophy may be a pathophysiologic factor. Significance The use of DPOE measures for screening and monitoring cochlear status of adult women should take into account the age, pure-tone thresholds, and noise exposure status of the subjects.
Stabilization of the wave equation with finite range Dirichlet boundary feedback

Abstract We consider the wave equation defined on a smooth bounded domain, Ω, with a one-dimensional range, non-local feedback operator applied to the Dirichlet boundary conditions, and acting on the velocity. The analysis is carried out on the space of optimal regularity of the problem, which is L 2 (Ω) × H −1 (Ω) . Under suitable assumptions, it is shown that the feedback system is strongly stable for dim Ω ⩾ 1, but cannot be uniformly stable unless dim Ω = 1.
Effects of agitation during VCM suspension polymerization

Experimental work is presented showing the effect of reactor agitation on final resin properties during vinyl chloride suspension polymerization. Experiments were carried out in a large pilot plant facility using a stirred batch reactor of over 5 cubic meters equipped with a turbine impeller and internal baffles. The effects of important agitation parameters such as impeller diameter, width, and speed are correlated with resin particle size distribution using the Weber number. The relationship of resin internal morphology with agitation is also presented using resin plasticizer absorption time and bulk density.
Observations on high-performance machines

The high speed computer area seems to be dominated by a continued reduction in the price of computer switching circuits and the approach of these circuits to speeds at which the velocity of light becomes an important factor. Barring some unforeseen dramatic change in technology, the outlook for increased computational speed in the classical sequential machine organization becomes increasingly grim. Simultaneity, or parallelism, therefore, becomes more and more essential if computer performance is to continue to increase.
Part III. Curriculum project reports: The science curriculum improvement study-report to the Piaget conference

The question of spontaneous development from preoperational to formal thinking as opposed to deliberate instruction to insure and accelerate this development is Karplus' topic. The aim of the Science Curriculum Improvement Study is described as that of fostering development of thinking to the formal operational level from natural philosophy to scientific literacy. Karplus, a physicist at the University of California, discusses the program of the Science Curriculum Improvement Study for grades K-2 in Piagelian terms.
Understanding Separation Anxiety Disorder

BACKGROUND. When children are acutely ill and life is threatened, separation anxiety can develop in parents and children. Separation anxiety has been studied through two traditions—as a normative phenomenon and as a disorder. SOURCE. A comprehensive review of the literature. OBJECTIVE. To analyze and evaluate the literature to derive clinical and research implications. CONCLUSIONS. Support was found for the development of interventions beyond the developmental stage of early childhood. The need for a family approach was evident.
Estimation of in-situ hydraulic diffusivity of rock masses

A method of estimating in-situ hydraulic diffusivity of rock masses by means of well-injection history and frequency of induced seismicity is presented. The method is based on the diffusion of injected fluid from a spherical cavity in a poroelastic half-space and the effective stress theory, as proposed byTerzaghi (1925, 1936) andHubbert andRubey (1959). Application of the method to two different regions, one in western New York and the other in Japan, resulted in estimated diffusivities of the order 103 and 104 cm2/sec, respectively. These values lie within the range of published estimates of in-situ diffusivity by other means, a summary of which is presented in tabular form. The calculated diffusivities suggest that the characteristic time of fluid diffusion is close to 0.1, rather than unity, as is sometimes assumed in the literature.
The orphan receptor TAK1 acts as a repressor of RAR-, RXR- and T3R-mediated signaling pathways.

Abstract Recently, we reported the cloning and characterization of the novel orphan receptor TAK1. In this study, we analyze the interaction of TAK1 with a variety of response elements (RE′s) and demonstrate that TAK1 binds effectively to RE′s composed of the core motif PuGGTCA configured in direct repeats spaced by one or more nucleotides. TAK1 bound poorly to palindromic or inverted palindromic motifs and was unable to bind to a single core motif, suggesting that a dimeric site is required for binding. Transfection experiments with CV-1 cells revealed that TAK1 is able to repress retinoid- and thyroid- hormone-induced transactivation through a subset of retinoid and thyroid hormone RE′s. Our studies indicate that the antagonism of RAR-mediated transactivation does not involve the formation of heterodimers between TAK1 and RAR or RXR but is due to the competition of TAK1 homodimers with RAR-RXR heterodimers and RXR homodimers for binding to RARE and RXRE, respectively. Our results suggest that the orphan receptor TAK1 can be a negative modulator of the regulation of gene expression mediated by retinoid and thyroid hormone signaling pathways.
Constraints to advanced psychiatric-mental health nursing practice

Constraints and barriers to advanced practice psychiatric nursing were reported by respondents of the Primary Mental Health and Advanced Practice Psychiatric Nursing survey of certified psychiatric clinical nurse specialists. Primary data (N = 507) were the qualitative responses to a survey item about constraints and secondary data were the literature and theoretical memos. Methodology was based on principles of qualitative data analysis and procedures for manifest and latent content analysis. Findings resulted in eight themes that explained both constraints and barriers to advanced practice: (1) reimbursement, (2) prescriptive authority, (3) admitting privileges, (4) bureaucracy, (5) practice environment, (6) colleagues, (7) image, and (8) personal. Themes were interpreted within the context of regulatory, market-based, and inter/intraprofessional constraints and barriers that led to suggestions for organizational and individual strategies for action. The survey was funded by the Society for Education and Research in Psychiatric-Mental Health Nursing with technical support from the Center for Mental Health Services.
Does the infective agent of scrapie replicate without nucleic acid? An assessment.

Abstract The dogma of a unique status for the scrapie agent falling outside the virological spectrum is critically examined in the light of the circumstances which gave rise to it, and it is concluded that such an extreme view cannot be justified. The dogma arose in the first place by a combination of inadequate methodology and the lack of comparable data from other systems. It has been sustained partly by the same factors, and partly by a general failure to understand the impact on all relevant investigations of the exceptionally tenacious binding of infective agent to host-cell (membrane) components. This has not only greatly distorted the experimental findings, but as a consequence has resulted in extensive data misinterpretation. It is concluded that there is no hard evidence for the absence of a nucleic acid core in the scrapie agent so long as it is accepted that this is very small — i.e., of the order of 30 KDa (kilodaltons) — and is embedded within a cell membrane component matrix which protects it by forming a sequestered microenvironment: further that this is by far the simplest hypothesis.
Modeling array of eccentric core-shell plasmonic spheres

Core-shell spheres have attracted significant interests in metamaterial community. Basically combination of a positive permittivity dielectric and a negative permittivity plasmonic material not only can control the resonances but also the effective material permittivity locally. This means one can use an array of coreshell spheres where, for instance, each has a different core size and as such tailor a desired material property across the array. Basically, any material can be engineered with core-shell spheres made from only two materials (the main concept of digital metamaterial).
Limited Transferrin Receptor Clustering Allows Rapid Diffusion of Canine Parvovirus into Clathrin Endocytic Structures

Viral pathogens usurp cell surface receptors to access clathrin endocytic structures, yet the mechanisms of virus incorporation into these structures remain incompletely understood. Here we used fluorescence microscopy to directly visualize the association of single canine parvovirus (CPV) capsids with cellular transferrin receptors (TfR) on the surfaces of live feline cells and to monitor how these CPV-TfR complexes access endocytic structures. We found that most capsids associated with fewer than five TfRs and that ∼25% of TfR-bound capsids laterally diffused into assembling clathrin-coated pits less than 30 s after attachment. Capsids that did not encounter a coated pit dissociated from the cell surface with a half-life of ∼30 s. Together, our results show how CPV exploits the natural mechanism of TfR endocytosis to engage the clathrin endocytic pathway and reveal that the low affinity of capsids for feline TfRs limits the residence time of capsids on the cell surface and thus the efficiency of virus internalization.
Predictors of Parenting Stress for Abusive and Nonabusive Mothers

We examined a model of parenting stress for abusive mothers (n = 80) and nonabusive mothers (n = 86) using linear regression analyses. Predictors in the model included (a) the degree to which mothers were bothered by child misbehavior, (b) mothers’ general psychological functioning, and (c) observed child behavior during parent–child interactions. Whether abuse status moderated the relations between each predictor and parenting stress was also explored. Results indicated that mothers’ psychological functioning significantly predicted parenting stress; however, neither mothers’ intolerance for their children’s misbehavior nor observed child behavior were significant predictors of parenting stress in the regression model. A test of moderation revealed a significant interaction between parental intolerance and abuse status such that intolerance predicted parenting stress level only for abusive mothers. A comparison of correlations indicated that abusive mothers’ level of parenting stress was more closely related to their intolerance for child conduct problems than to the child’s behavior during play with their mothers. Findings are discussed in terms of implications for interventions to reduce parenting stress experienced by nonabusive and abusive mothers.
Integrating palliative care in severe chronic obstructive lung disease

Palliative care services for patients with chronic obstructive pulmonary disease (COPD) have been limited in most health care schemes despite the significant impact its symptoms can have on quality of life (QOL). Palliative care must be integrated to address physical and emotional distress and QOL deterioration more effectively. Multi-factorial barriers in current health care systems impede the provision of palliative care, including the lack of familiarity among health care professionals. There are sparse evidence-based studies and guidelines for clinicians to better recognize the need for palliative care in COPD patients compared to the large experience and resources available to cancer patients and hospice care. The multidisciplinary approach of palliative care should help COPD patients navigate through the continuum of chronic disease management. Highest QOL, not necessarily the highest physiologic goals, with relief of physical and emotional suffering, are most important to patients. Hospice care, the last phase of palliative care, can be offered to COPD patients when their goal of care has changed from life-prolonging therapies to comfort treatment. We suggest a scheme for identifying COPD patients for palliative care and for delivering simultaneous disease-directed care to help patients live life to the fullest. Pulmonary rehabilitation offers the best venue for incorporating palliative care. We review the need for, barriers to, and key activities for integrating palliative care into the current health care management of patients living with COPD.
Ultrasonography Under Direct Visualization

A new device permits ultrasonic scanning of the posterior fundus under direct visualization by means of a modified fundus contact lens. An ultrasound profile of a specific fundus area is recorded. Scanning the same area during follow-up examinations provides an accurate assessment of the growth of fundus lesions.
Precast Prestressed Concrete Pavement Pilot Project near Georgetown, Texas

The use of precast concrete is rapidly becoming a viable method for repair and rehabilitation of portland cement concrete pavements, with several projects under construction or in development throughout the United States. Construction with precast concrete offers numerous benefits over conventional cast-in-place pavement construction. Most notable is how quickly a precast pavement can be opened to traffic. Precast panels can be placed during overnight or weekend operations and opened to traffic almost immediately. In addition, because precast panels are cast in a controlled environment, the durability of a precast pavement is also improved. In March 2002, the Texas Department of Transportation completed construction of a precast pavement pilot project aimed at testing and further developing a precast pavement concept developed by the Center for Transportation Research at The University of Texas at Austin. This project was constructed on a section of frontage road along Interstate 35 near Georgetown, Texas...