bluuebunny/crossref_metadata_2025 huggingface dataset:
Friction modelling in an engine valve train considering the sensitivity to lubricant formulation
Authors: Roshan R , Priest M , Neville A , Morina A , Xia X , Green J H , Warrens C P , Payne M J
Published: January 2009

In the automotive industry, within the last two decades, designers have noted widely adopted mathematical models to evaluate the tribological impact on the efficiency of the engine design and lubricant system. This study attempts to evaluate frictional losses in a Direct Acting Tappet (DAT)-type valve train through the use of tribofilm friction performance model in boundary and mixed lubrication conditions. A typical valve train friction model based on the elastohydrodynamic lubrication theory, mixed lubrication concept based on a transition model and tribofilm friction equation is described to evaluate the frictional and power losses in a cam cycle and to understand the sensitivity of the model to lubricant behaviour in boundary and mixed lubrication conditions. The chemical sensitivity of the additives used in automotive lubricants is characterized in terms of a typical friction modifier, molybdenum dithiocarbamate, in a model automotive engine lubricant also containing zinc dialkyldithiophosphate in synthetic polyalphaolefin base oil at a range of operating temperatures, sliding speeds, loads, initial surface roughness, and the initial lambda ratios. The mean friction torques predicted from the valve train friction model show good agreement with the experimental data from the motored cylinder head of a typical DAT design.
Impact corrosion wear properties and mechanism of lining board steels
Authors: Du X-D , Yang X-J , Wang Y-F , Wang L
Published: January 2009

By mechanical test, electrochemical test, and impact corrosion wear test, the combination properties, the impact corrosion and abrasion properties, and the mechanism of the low carbon CrNiMo steel and the high manganese steel used as lining board steel were investigated. The results show that the combination property of the low carbon CrNiMo steel is better than that of the high manganese steel. The impact corrosion and abrasion properties of the low carbon CrNiMo steel is also better than that of the high manganese steel at the same low impact energy.
Contrasting Measures of Adherence with Simple Drug Use, Medication Switching, and Therapeutic Duplication
Authors: Martin Bradley C , Wiley-Exley Elizabeth K , Richards Shirley , Domino Marisa E , Carey Timothy S , Sleath Betsy Lynn
Published: January 2009

BACKGROUND

Multiple measures of adherence have been reported in the research literature and it is difficult to determine which is best, as each is nuanced. Occurrences of medication switching and polypharmacy or therapeutic duplication can substantially complicate adherence calculations when adherence to a therapeutic class is sought.

OBJECTIVE

To contrast the Proportion of Days Covered (PDC) adherence metric with 2 variants of the Medication Possession Ratio (MPR, truncated MPR).

METHODS

This study was a retrospective analysis of the North Carolina Medicaid administrative claims data from July 1999 to June 2000. Data for patients with schizophrenia (ICD-9-CM code 295.xx) who were not part of a health maintenance organization, not hospitalized, and not pregnant, taking at least one antipsychotic, were aggregated for each person into person-quarters. The numerator for PDC was defined as the number of days one or more antipsychotics was available and the MPR numerator was defined as the total days’ supply of antipsychotics; both were divided by the total days in each person-quarter. Adherence rates were estimated for subjects who used only one antipsychotic, switched medications, or had therapeutic duplication in the quarter.

RESULTS

The final sample consisted of 25,200 person-quarters from 7069 individuals. For person-quarters with single antipsychotic use, adherence to antipsychotics as a class was: PDC 0.607, truncated MPR 0.640, and MPR 0.695 (p < 0.001). For person-quarters with switching, the average MPR was 0.690, truncated MPR was 0.624, and PDC was 0.562 (p < 0.001). In the presence of therapeutic duplication, the PDC was 0.669, truncated MPR was 0.774, and MPR was 1.238 (p < 0.001).

CONCLUSIONS

The PDC provides a more conservative estimate of adherence than the MPR across all types of users; however, the differences between the 2 methods are more substantial for persons switching therapy and prescribed therapeutic duplication, where MPR may overstate true adherence. The PDC should be considered when a measure of adherence to a class of medications is sought, particularly in clinical situations in which multiple medications within a class are often used concurrently.
Improving Swimming Pool Warning Signs
Authors: Loring Beth A. , Wiklund Michael E.
Published: January 2009

The U.S. Consumer Product Safety Commission sponsored us to perform a human factors evaluation of existing swimming pool warning signs. Our study covered warnings which convey the messages “NO DIVING” and “WATCH CHILDREN”. These warnings are particularly intended to reduce the incidence of diving accidents involving teenage boys and drowning accidents involving children under five; population groups that are over-represented in accident statistics. Our evaluation of twenty-two existing signs uncovered deviations from warning sign design principles and identified opportunities to improve each of the signs. Following the evaluation, we developed improved signs and tested them using teenage boys and mothers of young children as subjects. We then made final recommendations to the CPSC for improved signs.
Legibility and Comprehension of Traffic Sign Symbols
Authors: Paniati Jeffrey F.
Published: January 2009

In recent years, symbols have been used to improve the ability of traffic signs to communicate their messages. A study of traffic sign symbols was recently completed at the Federal Highway Administrations Turner-Fairbanks Highway Research Center in McLean, Virginia. In this study, a laboratory experiment was conducted to determine the relative legibility distance and driver comprehension for 22 symbol warning signs currently in use in the United States. The results showed that the legibility distance of symbols decreases with increasing driver age and that bold symbols of simple design provide the best legibility distance for all age groups. This study also showed that the legibility distance for symbolic signs can be equal to that of alphabetic signs or have as much as 4 times greater legibility distance depending on the message. The sign comprehension data indicated several symbols need redesign or increased driver education efforts.
Effects of Social Interaction on Performance and Mood State during Computer-Based Data Entry Work
Authors: Henning Robert A. , Krieg Edward F. , Sauter Steven L.
Published: January 2009

The effects of social interaction on performance and mood state were investigated for computer-based data entry work. A highly repetitive, screen-based, numeric data entry task was performed in a laboratory environment. Experienced data entry workers (N=16) performed the task under social and nonsocial conditions. Pairs of subjects worked at adjacent workstations in both conditions. During the nonsocial condition a room divider prevented visual contact and conversation was not permitted. During the social condition visual contact and conversation were permitted. Each condition consisted of three, 40-min work periods separated by 10-min rest breaks away from the workstation. The two subjects entered lines of data which had the same or an unequal number of characters so that interactions between task similarity and social/nonsocial conditions could be evaluated. Keystroke output, error rate, and the number of character corrections with the backspace key were scored for each work period. In addition, a survey of mood state was administered before and after each work period. Data analyses indicated that tension, irritation, perceived stress and error rate were less in the social condition. No effect on total keystroke output or backspace use was found in the social condition. No interaction between task similarity conditions and social/nonsocial conditions was found. These results suggest that social interaction during data entry work can benefit worker well-being and error rate performance without significantly affecting keystroke output. These results have implications for the design of work environments for data entry workers.
Naturalistic Observation of Adjustable VDT Stand Usage
Authors: Cornell Paul , Kokot Doug
Published: January 2009

Ergonomists have long recommended user adjustable furniture for office workers. A majority of the recommendations have been based upon anthropometric models of economically “correct” postures. Research validation of these proposals is sparse, and those that have been conducted are predominantly laboratory oriented. This research observed the use of adjustable furniture in a field setting. Three questions were addressed: 1) what are the preferred settings when the equipment has been used for a length of time?; 2) do people change the settings?; and 3) how do these measures relate to anthropometric data? The offices of 91 workers were measured covertly. Twenty one offices were measured once, 41 twice, and 29 three times. All the offices had an adjustable VDT stand with independent height and angle adjustments for both the keyboard and display. Seat height had a mean and standard deviation of 20.0 and 0.85 inches. The height of the home row of the keyboard had a mean of 29.1 and a standard deviation of 1.2 inches. For the display surface the mean and standard deviation were 29.7 and 1.3 inches. In terms of repeated measures, 62.9% of the chair heights, 57.1 % of the keyboard heights, and 91.4% of the display heights did not change. Of the observed changes, 90% were between 0.25 in and 0.75 inches. None of the observed heights correlated well with stature, seated eye height, or popliteal length. One correlation was 0.32, all others were less than 0.20. The results are similar to other published data in that the measured settings are much higher than anthropometric models would predict. More significantly, they do not match the new ANSI guideline nor the proposed CSA guideline for adjustable furniture. This suggests that the ergonomic theories behind these recommendations need to be modified to more closely reflect actual use products.
Team Process Measurement and Implications for Training
Authors: Prince Ashley , Brannick Michael T. , Prince Carolyn , Salas Eduardo
Published: January 2009

The purpose of this research was to establish the construct validity of a behaviorally anchored rating scale developed to measure team process behaviors. This scale contains six skills (i.e. leadership, assertiveness, decision making/mission analysis, situation awareness, communication, adaptability/flexibility) that were identified through a prior needs analysis with training specialists and subject matter experts. Student and instructor pilots (104 individuals, 51 teams) participated in two team tasks (simulated aviation tasks) which were designed to elicit the team process behaviors identified for the rating scale, and were rated on their behaviors. A multitrait-multimethod analysis on the resulting ratings (Campbell and Fiske, 1959) was conducted. Evidence of convergent and discriminant validity as well as some method bias were found when the method investigated was team task. Implications for the use of the team process scale in training are discussed.
Modeling Pilot Expertise in Air Combat
Authors: Thomas Gary S. , Obermayer Richard W. , Raspotnik William B. , Waag Wayne L.
Published: January 2009

The purpose of this effort was to model expert pilot performance and decision making in one-versus-one (1v1) air-to-air combat. Several knowledge-elicitation techniques were used to extract air combat expertise from a former fighter pilot, who served as the subject-matter-expert (SME). Unstructured and then structured interviews were used to elicit the goals and sub-goals of air-to-air combat, plus some of the pilot behaviors necessary to accomplish the goals. The SME also flew a number of combat sorties against another former fighter pilot in the Simulator for Air-to-Air Combat (SAAC) to demonstrate pilot performance required to accomplish the goals of air combat. Based on the SME's verbal protocols, a group of air combat rules were developed. A rule-based production system was then designed to incorporate the resulting knowledge base. The production system was also designed to be capable of analyzing an existing data base of air combat engagements. Expert system development required additional input from the SME to identify specific values of flight parameters required by the production system. Upon completion and SME verification of the expert model, it will be validated by comparing its performance to that of our SME in simulated air-to-air combat. If the model can successfully describe expert pilot performance, the model will be used to provide diagnostic performance feedback in conjunction with SAAC training.
Training and Evaluating Team Process Skills in the Commercial Aviation Environment
Authors: Law J. Randolph , McFadden Terry J.
Published: January 2009

The majority of aviation incidents and accidents are attributable to human error (Billings & Reynard, 1984). Most of these human errors involve the ineffective use of team process factors, which are often referred to as Crew Resource Management (CRM) skills in the commercial aviation literature (Helmreich & Foushee, in press). In addition to these applied concerns, a revised version of McGrath's (1964) theory of group performance (Foushee & Helmreich, 1988) suggests that one must analyze the process (i.e., team process) by which a group's inputs (e.g., personality, attitudes) are transformed into group outcomes (e.g., task performance, mission safety) in order to understand how a task-oriented group functions. Therefore, team process attracts theoretical as well as practical interest. The NASA/UT/FAA Line/LOS Checklist (LLC: Helmreich, Wilhelm, Kello, Taggart, & Butler 1991) is one measure of team process that has proven useful in assessing CRM skills in training and in actual Line operations. This paper briefly reviews concepts in team process and summarizes the LLC research findings pertaining to the use of CRM skills in commercial aviation.
Field Test of Video Game Trainer
Authors: Hart Sandra G. , Battiste Vernol
Published: January 2009

A field study was conducted at the US Army Aviation Center to determine whether workload-coping and attention-management skills developed through structured video game experience would generalize to flight training. Three groups of 24 trainees were compared: (1) One received 10 hours of training on an IBM-PC version of Space Fortress, replicating an earlier study; (2) The second played a commerical video game (Apache Strike) for 10 hours which also required tracking, monitoring, situation assessment, and memory; (3) The third matched group receive no game training. Flight school records were monitored during the next 18 mos to compare performance of the three groups during initial flight training. Check ride ratings began to show an advantage for the group trained with Space Fortress by the Instrument stage of training, as predicted. Furthermore, attrition rates were lower for this group, replicating the results of an earlier study conducted by Gopher (1990) in the Israeli Air Force Flight School.
Human Factors in Maritime Applications: A New Opportunity for Multi-Modal Transportation Research
Authors: Sanquist Thomas F.
Published: January 2009

Human error has been shown to cause 65 − 80% of maritime casualties; this figure is similar to that of other industries. However, there has been little systematic research and development work in the area of maritime human factors. This paper presents a model of five technical domains that comprise a useful framework for conceptualizing human factors in the maritime industries. The multi-modal research potential in the areas of fatigue and the cognitive impacts of automation are discussed.
Liveware Survey of Human Systems Integration (HSI) Technologies: Need for Comprehensive Survey and Available Database
Authors: Gentner Frank C. , Crissey Mona J.
Published: January 2009

Downsizing the Department of Defense (DoD) means accomplishing more with fewer people. Enlightened design that considers all requirement and interaction issues simultaneously is the key to productivity. In the past, human issues have been difficult to quantify or depict during the systems engineering process. Recently, there has been an explosion of affordable HSI technologies. Despite the new DoD directives that require HSI analyses throughout acquisition, it is difficult to identify the most appropriate technology for HSI analyses. Defense acquisition managers, contractors, and the HSI research and development (R&D) community need a database of information about HSI tools, databases, and test facilities. They need this database to identify technology available in each of the Liveware domains of Manpower, Personnel, Training, (MPT) Safety, Health Hazard Prevention, and Human Factors Engineering (HFE) and to fully integrate human consideration into the acquisition process. However, no comprehensive catalog of HSI technology exists. Under the sponsorship of the Office of the Assistant Secretary of Defense (Force Management and Personnel) HSI office and North Atlantic Treaty Organization (NATO) Research Study Group.21 (RSG.21), TPDC and CSERIAC are surveying the HSI community for a comprehensive database of HSI technologies, an ambitious effort requiring the help of all HSI technology developers, owners, and users.

This paper reviews previous HSI-related technology studies. It supports the thesis that a comprehensive survey and database are needed to improve prioritization of HSI technology R&D aid in HSI technology identification and use; and take full advantage of the new acquisition climate. It also describes the survey and database which is now being populated, and highlights the need for HSI community participation.
Human Engineering Requirements for Rapid Prototyping of Operator/Maintainer Interfaces: A Proposed Military Standard
Authors: Steiner Bruce A.
Published: January 2009

A proposed military standard was developed that establishes and defines the methodology to incorporate the use of rapid prototyping of operator/maintainer machine interface design into the system design process. The specification includes the work to be accomplished by the contractor or subcontractor in prototyping interfaces and evaluating those interfaces under operationally equivalent conditions. The tasks outlined provide the basis for defining, integrating and validating operator interface prototyping methodologies, as well as the software interface. Two data item descriptions were also developed; Rapid Prototyping Program Plan, and Rapid Prototyping Design Approach Document. The Rapid Prototyping Program Plan is the single document which describes the contractor's entire system prototype engineering program, identifies its elements, and explains how the elements will be managed. The Rapid Prototyping Design Approach Document provides a source of data with which to evaluate the extent to which the rapid prototyping design meets system engineering requirements and other human engineering criteria. This paper presents the main topics from the proposed standard.
Abilities and Individual Differences in Complex Skill Acquisition
Authors: Ackerman Phillip L.
Published: January 2009

A theoretically - driven, information processing based examination of ability - performance relations during the acquisition of a high - fidelity complex air traffic controller simulation task is described. Two laboratory experiments and one field experiment are reviewed that describe the results of extensive ability testing (including measures of general, reasoning, spatial, perceptual speed, and perceptual/psychomotor abilities) and individual differences in skill acquisition over protracted skill-learning sessions. Laboratory studies examine individual differences in the acquisition of skills on TRACON® - a Terminal Radar Approach Controller simulation. The field investigation examines acquisition of skills by FAA Air Traffic Controller Trainees. Results are reported from perspective of global/component abilities, and global/component criterion task performance measures. Results validate and further extend the Ackerman (1988) theory of the cognitive ability determinants of individual differences in skill acquisition. This research program demonstrates the benefits of ability component and task component levels of analysis over global analyses of ability - skill relations. Implications are discussed for developing refined selection instruments for the prediction of air traffic controller training success, and for other job tasks with demands for inconsistent information processing, as well as implications for design of tailored training procedures.
Acquisition and Transfer of Spatial Rotation and Assembly Skills: Two Speed-Accuracy Studies
Authors: Lohman David F.
Published: January 2009

Two studies of the effects of practice on the acquisition and transfer of spatial skills are reported. Both used the methodology of the speed-accuracy study to generate performance curves for each subject in each condition. Interpretation of the parameters of models fitted to these data was guided by McClelland's (1979) cascade model. In the first study, subjects practiced either rotating or assembling polygons. Later, they were administered a transfer rotation or assembly task that presented either practiced or nonpracticed stimuli. In the second study, subjects practiced assembling forms for three sessions and were later posttested on the same transfer task used in Study 1. Following McClelland (1979), differences in asymptotes, curvatures, and intercepts of speed-accuracy curves between conditions were interpreted as reflecting changes in stimulus familiarity, changes in a slow (or rate limiting) process, and changes in a fast (or task-specific) process, respectively. Implications of the research for training and assessment of spatial abilities are discussed.
Effects of an Aversive Vicarious Experience and Modelling on Perceived Risk and Self-Protective Behavior
Authors: Chy-Dejoras Evangeline A.
Published: January 2009

A 2 × 3 between-subjects design was used to determine the effects of modelling and aversiveness of a vicarious experience on perceived risk and self-protective behavior. Modelling and aversiveness of experience were manipulated using an instructional videotape. Unprotected model and protected model conditions were compared. Benign, slightly aversive, and highly aversive conditions were compared. The dependent variables were self-protective behavior and perceptions regarding the hazardousness of the product, severity of injury, likelihood of injury, likelihood of an accident, and familiarity with the product.

More subjects in the protected model group exhibited self-protective behavior compared to the control group. There was no difference in levels of perceived risk between the two groups. Aversiveness had an effect on self-protective behavior. The slightly aversive group showed an incidence of self-protective behavior significantly greater than that of the control group and the highly aversive group. Examination of the nature of manipulation used in the slightly aversive condition suggests that an ambiguous portrayal of the consequences of a hazard while implying its potential to inflict harm causes people to behave cautiously. The incidence of self-protective behavior in the highly aversive group did not differ significantly from that of the control group despite a significant difference in perceived levels of hazardousness. This is explained as a manifestation of the so-called “self-protective attribution of responsibility.” Perceived hazardousness was found to be the primary predictor of self-protective behavior. Perceived severity and likelihood of injury were found to be the primary predictors of perceived hazardousness. A strong association was found between self-protective behavior and perceived personal susceptibility to injury.
A Pilot Study on the Perceived Urgency of Multitone and Frequency-Modulated Warning Signals
Authors: Haas E. C.
Published: January 2009

In some environments, there is a serious mismatch between the perceived (psychoacoustic) urgency of a warning and its situational urgency. This pilot study investigated effect of pulse format, pulse duration, and time between pulses on the perceived urgency of warning signals. The intent was to determine the best combination of variables and levels of variables to use in a formal study on the perceived urgency of warning signals. The results indicated that only pulse format and time between pulses were significant. Subjects rated sequential pulses as being less urgent than any other format. Signals with shorter inter-pulse intervals were rated as significantly more urgent. Pulse format and time between pulses were determined to be variables which should be used in future research.
Cognitive Engineering in Radiation Screening for Homeland Security
Authors: Sanquist Thomas F. , Minsk Brian , Parasuraman Raja
Published: January 2009

Cognitive engineering methods in a large-scale homeland security program are described. Screening cargo containers at seaports for illicit radioactive material involves substantial staff, technology, and human operator decision making. The systems engineering model used by the radiation portal monitor (RPM) program entails elements similar to the incremental commitment model, which provides a risk-based focus for applications of cognitive engineering. This model includes methods for defining opportunities and context of use, methods for requirements and design solutions, and methods for evaluation. The application examples illustrate each of these general areas through work domain analysis, signal detection modeling, design of displays for radiation threat likelihood, and evaluation of the design concepts with field test data. The signal detection analysis shows how system detection sensitivity requirements for design can be established for low-probability, high-consequence events such as threats. The threat display concept developed by cognitive engineers has been implemented in new fielded systems. The success of cognitive engineering in the RPM program is largely a result of working with an incremental approach to systems engineering. This perspective provides application focus to those areas most likely to benefit from cognitive engineering within the overall constraints of the work domain, program schedule, and budget.
Human-Automation Interaction
Authors: Sheridan Thomas B. , Parasuraman Raja
Published: January 2009

Automation does not mean humans are replaced; quite the opposite. Increasingly, humans are asked to interact with automation in complex and typically large-scale systems, including aircraft and air traffic control, nuclear power, manufacturing plants, military systems, homes, and hospitals. This is not an easy or error-free task for either the system designer or the human operator/automation supervisor, especially as computer technology becomes ever more sophisticated. This review outlines recent research and challenges in the area, including taxonomies and qualitative models of human-automation interaction; descriptions of automation-related accidents and studies of adaptive automation; and social, political, and ethical issues.
Digital Human Modeling for Workspace Design
Authors: Chaffin Don B.
Published: January 2009

Digital human modeling (DHM) technology offers human factors/ergonomics specialists the promise of an efficient means to simulate a large variety of ergonomics issues early in the design of products and manufacturing workstations. It rests on the premise that most products and manufacturing work settings are specified and designed by using sophisticated computer-aided design (CAD) systems. By integrating a computer-rendered avatar (or hominoid) and the CAD-rendered graphics of a prospective workspace, one can simulate issues regarding who can fit, reach, see, manipulate, and so on. In this chapter, I briefly describe the development of various DHM methods to improve CAD systems. Past concerns about early DHM methods are discussed, followed by a description of some of the recent major developments that represent attempts by various groups to address the early concerns. In this latter context, methods are described for using anthropometric databases to ensure that population shape and size are well modeled. Efforts to integrate various biomechanical models into DHM systems also are described, followed by a section that outlines how human motions are being modeled in different DHM systems. In a final section, I discuss recent work to merge cognitive models of human performance with DHM models of manual tasks. Much has been accomplished in recent years to make digital human models more useful and effective in resolving ergonomics issues during the design of products and manufacturing processes, but much remains to be learned and applied in this rapidly evolving aspect of ergonomics.
Distinct Memory Signatures in the Hippocampus: Intentional States Distinguish Match and Mismatch Enhancement Signals
Authors: Duncan Katherine , Curtis Clayton , Davachi Lila
Published: January 2009

Incoming events that match or mismatch stored representations are thought to influence the ability of the hippocampus to switch between memory encoding and retrieval modes. Electrophysiological work has dissociated match and mismatch signals in the monkey perirhinal cortex, where match signals were selective for matches to goal states, whereas mismatch signals were not modulated by intention (Miller and Desimone, 1994). To investigate whether the theoretically important relational match and mismatch signals in the hippocampus are modulated by goal states, we fully crossed whether a probe stimulus relationally matched or mismatched a previously perceived image or goal state. Subjects performed two working memory tasks in which they either responded “yes” to probes that were identical to the previous sample scene or, after performing a relational manipulation of the scene, responded “yes” only to a probe that was identical to this perceptually novel image. Using functional magnetic resonance imaging, we found evidence for relational match enhancements bilaterally in the hippocampus that were selective for matches between the probe stimulus and goal state, but were not modulated by whether that goal was perceptually novel. Moreover, we found evidence for a complementary hippocampal mismatch enhancement that was triggered by stimuli containing salient perceptual manipulations. Our results provided evidence for parallel memory signatures in the hippocampus: a controlled match signal that can detect matches to internally generated goal states and an automatic mismatch signal that can identify unpredicted perceptual novelty.
Persistent Pain Is Dependent on Spinal Mitochondrial Antioxidant Levels
Authors: Schwartz Erica S. , Kim Hee Young , Wang Jigong , Lee Inhyung , Klann Eric , Chung Jin Mo , Chung Kyungsoon
Published: January 2009

Reactive oxygen species (ROS) scavengers have been shown to relieve persistent pain; however, the mechanism is not clearly understood. Superoxide produced from mitochondrial oxidative phosphorylation is considered the major source of ROS in neurons during excitation where mitochondrial superoxide levels are normally controlled by superoxide dismutase (SOD-2). The present study hypothesizes that capsaicin-induced secondary hyperalgesia is a consequence of superoxide build-up in spinal dorsal horn neurons and SOD-2 is a major determinant. To test this hypothesis, the spinal levels of SOD-2 activity, inactivated SOD-2 proteins, and mitochondrial superoxide were measured and correlated to the levels of capsaicin-induced secondary hyperalgesia in mice with and without SOD-2 manipulations. The data suggest that superoxide accumulation is a culprit in the abnormal sensory processing in the spinal cord in capsaicin-induced secondary hyperalgesia. Our studies also support the notion that SOD-2 nitration is a critical mechanism that maintains elevated superoxide levels in the spinal cord after capsaicin treatment. Finally, our findings suggest a therapeutic potential for the manipulation of spinal SOD-2 activity in pain conditions.
Neurokinin 1 Receptors Regulate Morphine-Induced Endocytosis and Desensitization of μ-Opioid Receptors in CNS Neurons
Authors: Yu Y. Joy , Arttamangkul Seksiri , Evans Christopher J. , Williams John T. , von Zastrow Mark
Published: January 2009

μ-Opioid receptors (MORs) are G-protein-coupled receptors (GPCRs) that mediate the physiological effects of endogenous opioid neuropeptides and opiate drugs such as morphine. MORs are coexpressed with neurokinin 1 receptors (NK1Rs) in several regions of the CNS that control opioid dependence and reward. NK1R activation affects opioid reward specifically, however, and the cellular basis for this specificity is unknown. We found that ligand-induced activation of NK1Rs produces a cell-autonomous and nonreciprocal inhibition of MOR endocytosis induced by diverse opioids. Studies using epitope-tagged receptors expressed in cultured striatal neurons and a neuroblastoma cell model indicated that this heterologous regulation is mediated by NK1R-dependent sequestration of arrestins on endosome membranes. First, endocytic inhibition mediated by wild-type NK1Rs was overcome in cells overexpressing β-arrestin2, a major arrestin isoform expressed in striatum. Second, NK1R activation promoted sequestration of β-arrestin2 on endosomes, whereas MOR activation did not. Third, heterologous inhibition of MOR endocytosis was prevented by mutational disruption of β-arrestin2 sequestration by NK1Rs. NK1R-mediated regulation of MOR trafficking was associated with reduced opioid-induced desensitization of adenylyl cyclase signaling in striatal neurons. Furthermore, heterologous regulation of MOR trafficking was observed in both amygdala and locus ceruleus neurons that naturally coexpress these receptors. These results identify a cell-autonomous mechanism that may underlie the highly specific effects of NK1R on opioid signaling and suggest, more generally, that receptor-specific trafficking of arrestins may represent a fundamental mechanism for coordinating distinct GPCR-mediated signals at the level of individual CNS neurons.
Low-temperature instability of Ti2SnC: A combined transmission electron microscopy, differential scanning calorimetry, and x-ray diffraction investigations
Authors: Zhang J. , Liu B. , Wang J.Y. , Zhou Y.C.
Published: January 2009

Transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and x-ray diffraction (XRD) investigations were conducted on the hot-pressed Ti2SnC bulk ceramic. Microstructure features of bulk Ti2SnC ceramic were characterized by using TEM, and a needle-shaped β-Sn precipitation was observed inside Ti2SnC grains with the orientation relationship: (0001) Ti2SnC // (200) Sn and Ti2SnC // [001] Sn. With the combination of DSC and XRD analyses, the precipitation of metallic Sn was demonstrated to be a thermal stress-induced process during the cooling procedure. The reheating temperature, even as low as 400 °C, could trigger the precipitation of Sn from Ti2SnC, which indicated the low-temperature instability of Ti2SnC. A substoichiometry Ti2SnxC formed after depletion of Sn from ternary Ti2SnC phase. Under electron beam irradiation, metallic Sn was observed diffusing back into Ti2SnxC. Furthermore, a new Ti7SnC6 phase with the lattice constants of a = 0.32 and c = 4.1 nm was identified and added in the Ti-Sn-C ternary system.
Effects of iron-phosphate coating on Ru dissolution in the PtRu thin-film electrodes
Authors: Park Yejun , Lee Byungjoo , Kim Chunjoong , Kim Jongmin , Park Byungwoo
Published: January 2009

The effects of FePO4 nanoscale coating on PtRu thin films were investigated on the block of Ru crossover. Ru dissolution was examined by the accelerated-potential cycles between 0.4 and 1.05 V. The results showed that Ru dissolution from FePO4-coated PtRu surface was inevitable due to the direct contact between the PtRu surface and aqueous electrolyte. However, the FePO4 coating layer on PtRu thin-film electrodes effectively retained the dissolved Ru species, thus preventing the dissolved Ru species from diffusing into the electrolyte. Moreover, the retained Ru species within the FePO4-coating layer were redeposited onto the PtRu surface during the cycling in the fresh electrolyte.
Comparison of bulk metallic glass formation between Cu-Hf binary and Cu-Hf-Al ternary alloys
Authors: Jia Peng , Xu Jian
Published: January 2009

Optimized compositions for bulk metallic glass (BMG) formation have been determined for the Cu−Hf binary and Cu−Hf−Al ternary systems. The Cu−Hf−Al BMG-forming composition region is identified to correlate with the (L → Cu10Hf7 + CuHf2 + CuHfAl) eutectic reaction. The eutectic temperature is reduced by nearly 50 K relative to that of the binary eutectic, demonstrating the significant role of the third element Al in stabilizing the liquid. The fragility parameter D* of the Cu55Hf45 binary and Cu49Hf42Al9 ternary supercooled liquid was determined from relaxation time measurements, indicating that Al incorporation also leads to a “stronger” liquid. The combination of these thermodynamic and kinetic effects is responsible for the dramatic enhancement of glass-forming ability from the Cu−Hf binary to the Cu−Hf−Al ternary.
Correlation between Barkhausen noise and mechanical sensitivity in FINEMET-type materials
Authors: Eszenyi G. , Szabó S. , Harasztosi L. , Zámborszky F. , Nyéki J. , Erdélyi Z. , Beke D.L.
Published: January 2009

FINEMET-type (Fe75Si15NbBCu) ribbons were heat treated, and their magnetic properties were analyzed. Permeability, thermal, and mechanical sensitivities were measured by commonly used industrial methods, and these properties were correlated with measured magnetic Barkhausen noise parameters. Distributions of peak area, A, and peak noise energy, E, were evaluated. Distribution functions of noise parameters, P(x), were in good agreement with the theory of self-organized criticality (SOC), satisfying power laws in the form P(x)∼x−α. It is found that the noise did not considerably depend on the temperature sensitivity parameter and on the permeability of ribbons. However, a useful correlation between the noise parameters and mechanical sensitivity has been observed. Minimal noise was detected for samples with negligible mechanical sensitivity in an amorphous-nanocrystalline composite state obtained by a heat treatment at 853 K.
Low-temperature sintering of dense lanthanum silicate electrolytes with apatite-type structure using an organic precipitant synthesized nanopowder
Authors: Hwan Jo Seung , Muralidharan P. , Kim Do Kyung
Published: January 2009

Highly sinterable La10Si6O27 and La10Si5.5M0.5O27 (M = Mg, and Al) nanopowders with apatite-type structure have been synthesized via a homogeneous precipitation method using diethylamine (DEA) as a precipitant. The synthetic approach using an organic precipitant with dispersant characteristics is advantageous in configuring weakly agglomerated nanopowders, leading to desirable sintering activity. X-ray diffraction powder patterns confirmed the single-phase crystalline lanthanum silicate of hexagonal apatite structure at 800 °C, which is a relatively lower calcination temperature compared to conventionally prepared samples. Transmission electron microscopy images revealed particles ∼30 nm in size with a high degree of crystallinity. A dense grain morphology was recognized from the scanning electron microscopy images of the polished surface of the pellets that were sintered at 1400 and 1500 °C for 10 h. This low-temperature sintering is significant because conventional powder processing requires a temperature above 1700 °C to obtain the same dense electrolyte. The doped-lanthanum silicate electrolyte prepared by the DEA process and sintered at 1500 °C for 10 h exhibited electrical conductivity comparable with samples prepared at much higher sintering temperature (>1700 °C).
Microstructure evolution of Ca0.33CoO2 thin films investigated by high-angle annular dark-field scanning transmissionelectron microscopy
Authors: Huang Rong , Mizoguchi Teruyasu , Sugiura Kenji , Nakagawa Shin-ichi , Ohta Hiromichi , Saito Tomohiro , Koumoto Kunihito , Hirayama Tsukasa , Ikuhara Yuichi
Published: January 2009

Microstructures of epitaxial Ca0.33CoO2 thin films, which were grown on m plane and c(0001) plane of α–Al2O3 by the reactive solid-phase epitaxy (R-SPE) method and the subsequent ion-exchange treatment, were investigated in detail by using selected-area electron diffraction, high-resolution transmission electron microcopy, spherical-aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (Cs-corrected HAADF-STEM), and electron energy-loss spectroscopy (EELS). Detailed electron diffraction analyses reveal that the orientation relationships between Ca0.33CoO2 thin film and substrate are and , having an angle of about 43° with for the film deposited on m plane, and and for the film deposited on c(0001) plane though a Ca–Al–O amorphous layer formed between them. CoO seed layer near the interface and residual Co3O4 phase inside the films were observed and identified by HAADF-STEM and EELS in both samples. Such microstructural configuration indicates that the processes of film growth during R-SPE are (i) oxidation of CoO into Co3O4 with residual CoO layer near the interface and (ii) intercalation of Na+ layer into Co3O4 to achieve the layered NaxCoO2 film while forming Na–Al–O amorphous layer at the interface.
Preparation of crystallized glass for application in fiber-type devices
Authors: Masai Hirokazu , Iwafuchi Naoki , Takahashi Yoshihiro , Fujiwara Takumi , Ohara Seiki , Kondo Yuki , Sugimoto Naoki
Published: January 2009

We have demonstrated that 30BaO–15TiO2–30GeO2–25SiO2 (BTGS25) glass is a candidate for fiber-type nonlinear optical devices using crystallization of glass matrix. We determined the glass composition is suitable for crystallized fiber using partial substitution of Ge in 30BaO–15TiO2–55GeO2 (BTG55) by Si. The BTGS25 satisfied both thermal stability for fiber drawing and electronic polarizability for nonlinear optical property. After crystallization, the BTGS25 bulk crystallized glass showed surface crystallization behavior with the polar c-orientation of fresnoite phase, which was favorable for large second-order optical susceptibility. Following the results of the bulk glass, we prepared the BTGS25 glass fiber without precipitation of fresnoite crystallites. The BTGS25 crystallized fiber also showed c-oriented surface crystallization of fresnoite and second harmonic generation, which shows that the crystallized fiber is a promising material for fiber-type optical active devices.
Thermotropic behavior of sodium cholesteryl carbonate
Authors: Chuealee Rabkwan , Wiedmann Timothy S. , Srichana Teerapol
Published: January 2009

Sodium cholesteryl carbonate ester (SCC) was synthesized, and its phase behavior was studied. The chemical structure was assessed by solid-state infrared spectroscopy based on vibration analysis. The wave number at 1705 and 1276 cm−1corresponds to a carbonyl carbonate and O–C–O stretching of SCC, respectively. Molecular structure of SCC was further investigated with1H and13C NMR spectroscopy. The chemical shift, for the carbonyl carbonate resonance appeared at 155.5 ppm. A molecular mass of SCC was atm/zof 452. Differential scanning calorimetry (DSC), video-enhanced microscopy (VEM) together with polarized light microscopy, and small-angle x-ray scattering (SAXS) were used to characterize the phase behavior as a function of temperature of SCC. Liquid crystalline phase was formed with SCC. Based on the thermal properties and x-ray diffraction, it appears that SCC forms a structure analogous to the type II monolayer structure observed with cholesterol esters.
The effect of very high barium content in the precursor on the properties of GdBCO single grain bulk superconductors
Authors: Shi Yunhua , Babu N. Hari , Iida Kazumasa , Cardwell David A.
Published: January 2009

A new melt processing route for the fabrication of large grain Gd-Ba-Cu-O (GdBCO) bulk superconductors has been developed based on the use of novel GdBa4Cu3O8−δ (Gd-143) and GdBa6Cu3O10−δ (Gd-163) precursor compositions. The new processing route enables the fabrication of large single grains from precursor powders that contain high concentrations of Ba. The superconducting properties and microstructures of GdBCO single grains with extra Ba fabricated via this new processing route are reported. Most importantly, the possible formation of a new form of Gd1+xBa2−xCu3O7−δ solid solution (Gd-123ss) with x < 0 in single grains fabricated from the Ba-rich precursor are discussed for the first time based on the superconducting, chemical, and structural properties of the large GdBCO grains.
Effect of heat treatment on the reflective spectrum of zinc oxide powders
Authors: Mikhailov M.M. , Neshchimenko V.V. , Li Chundong , He Shiyu , Yang Dezhuang
Published: January 2009

To determine the optimum baking temperatures for nanopowder introduction, the variation of reflective spectrum of baked zinc oxide powders, which are used as pigments for thermal control coatings of spacecraft, has been investigated over the wavelength range of 0.225–2.5 μm after being baked at temperatures between 400 °C and 850 °C. It has been established that baking temperatures over 750 °C result in a reduction of spectral reflectance in the visible light spectrum region. This is due to the formation of absorption bands of intrinsic point defects and thus increasing the spectral reflectance in the near-infrared region. The optimum temperature is 650 °C at which the bleaching effect was observed long after heat treatment. Moreover, an increase in the reflection coefficient occurs in the regions of 380–450 nm and 1100–2500 nm in this case.
Social Justice and Human Caring: A Model of Caring Science as a Hopeful Paradigm for Moral Justice for Humanity
Authors: Watson Jean
Published: January 2009

The only true standard of greatness of any civilization is our sense of social and moral responsibility in translating material wealth to human values and achieving our full potential as a caring society.

— The Right Honorable Norman Kirk, Former Prime Minister of New Zealand
Assessing and Addressing Domestic Violence Experienced by Incarcerated Women
Authors: Zust Barbara L.
Published: January 2009

A significant percentage of incarcerated women are victims of domestic violence, forced to be involved in illegal activity orchestrated by their abusive partners. Because intimate partner violence is not routinely assessed in prisons, the impact of partner violence is not always recognized or addressed.
Stereotypes and Social Injustice
Authors: Steffen Lori
Published: January 2009

A group presentation by nursing students created an opportunity for their classmates to experience firsth and the effects of stereotyping and its impact on the delivery of health care and social services.
Telephone Coaching for Clinical Nurse Managers
Authors: Koloroutis Mary
Published: January 2009

The coaching process enabled me to take time away from my reactive day to think and plan and imagine.

—Clinical Nurse Manager
Defining Nursing: A Linguistic View
Authors: de Ruiter Hans-Peter
Published: January 2009

A nurse who has practiced in different countries reflects on the words used in various languages to name our profession, and what those words have to say about the deeper meaning of nursing.