bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study of Edema Disease in Pigs in Vietnam with Particular Reference to the Use of Autovaccine for the Prevention of Disease
Authors: PHU CU HUU , NGUYEN N.N. , DO N.T. , NGUYEN X.H. , AU X.T. , VAN T.H. , VU N.Q. , DAO T.H.
Published: November 2006

Abstract:  Edema disease caused by Escherichia coli is one of the most common diseases in postweaning piglets throughout Vietnam. Verotoxigenic E. coli (VTEC) was isolated from 197 of 261 samples (75.5%). All isolates were confirmed by basic biochemical tests and carbohydrate fermentation characteristics. Of these, 70.1% of isolates are hemolytic, 45% isolates belonged to serotypes O149:K91, possessed the VT2e gene, and was the most predominant VTEC pathotype associated with edema disease in pigs. Serogroup O139 accounted for 30% of the isolates, followed by serogroup O138 and O141 (25%). In addition to VT2e gene, the ST (72.7%) and LT (52.7%) genes were also recognized. A total of 10 representative isolates were subjected to toxigenicity testing by intraperitoneal injection in mice and experimental infection in pigs. It was shown that 100% of the mice were killed 17–24 h post injection (p.i.). All pigs experimentally infected with challenge strains and developed typical symptoms of edema disease 36–72 h p.i. A multivalent killed whole‐cells vaccine containing aluminum hydroxide was prepared from 5 VTEC strains. The vaccine was 100% safe when administered by the intramuscular route into the pigs. A field trial for over 100,000 pigs (21–90 days old) showed that vaccinated pigs were protected against edema disease at a level of 90% compared to 100% of pigs from unvaccinated groups.
Preliminary Analysis of Tetracycline Residues in Marketed Pork in Hanoi, Vietnam
Authors: VAN NHIEM DUONG , PAULSEN PETER , SURIYASATHAPORN WITAYA , SMULDERS FRANS J.M. , KYULE MOSES N. , BAUMANN MAXIMILIAN P.O. , ZESSIN KARL H. , HONG NGAN PHAM
Published: November 2006

Abstract:  A cross‐sectional survey was designed to investigate the proportion of tetracycline residues in marketed pork in suburb and urban districts in Hanoi. A total of 290 raw muscle samples were randomly collected from open markets in these districts. The samples were qualitatively screened for tetracycline residues using the agar inhibition test, and Bacillus cereus (ATCC 11778) as the reference strain. The inconclusive samples were then analyzed using high‐performance liquid chromatography (HPLC). The positive samples from either test were defined as positive results. Overall, 5.5% of all collected samples were positive for tetracycline residues. The proportion of positive samples from shops in suburb districts was significantly (P < 0.05) different from those collected from shops in urban districts. So, the factor of region was identified as a risk factor of tetracycline residue proportion in raw pork with an odds ratio (OR) of 4.03 (95% CI = 1.12, 14.45). For the other factors, such as season, type of shop, type of abattoir, origin of meat, etc., the difference in proportion of positive samples within each factor was substantial but not statistically significant. These factors were identified as nonrisk factors. Such a high proportion may pose a potential hazard to public health, particularly since they might induce drug resistance of pathogenic micro‐organisms.
Antimicrobial Resistance Phenotypes of ETEC Isolates from Piglets with Diarrhea in North Vietnam
Authors: DO N.T. , CU H.P. , NGUYEN N.N. , NGUYEN X.H. , AU X.T. , VAN T.H. , VU N.Q. , TROTT D.J.
Published: November 2006

Abstract:  Both disk diffusion and broth micro‐dilution assays were employed to determine the level of resistance in Enterotoxigenic Escherichia coli (ETEC) isolates (n= 170) obtained from preweaning piglet colibacillosis from the two different pig production systems (commercial piggeries and small holder farmers) in Vietnam. Overall, tetracycline, streptomycin, amoxicillin, trimethoprim/sulfamethoxazole, and chloramphenicol showed markedly higher rates of resistance. Both apramycin and ceftiofur are active against all ETEC isolates. These antimicrobials could be recommended as the drugs of choice for the treatment of E. coli infections in young pigs in North Vietnam. Resistance to third‐generation cephalosporin (ceftiofur, ceftazidime, and cefoxitin) was not observed in Vietnamese ETEC isolates. Multiple resistances to greater than three antimicrobials were widely distributed (∼ 79.4%).
Quantification of Regulatory T Cells Enables the Identification of High-Risk Breast Cancer Patients and Those at Risk of Late Relapse
Authors: Bates Gaynor J. , Fox Stephen B. , Han Cheng , Leek Russell D. , Garcia José F. , Harris Adrian L. , Banham Alison H.
Published: November 2006

Purpose

To assess the clinical significance of tumor-infiltrating FOXP3-positive regulatory T cells (TR) in breast cancer patients with long-term follow-up.

Patients and Methods

FOXP3-positive TR were detected by immunohistochemistry with our new, extensively characterized FOXP3 monoclonal antibody, 236A/E7. Numbers of FOXP3-positive lymphocytes in tissue microarray cores from pure ductal carcinoma in situ (DCIS; n = 62), invasive breast cancer (n = 237) or from comparable areas of normal terminal duct lobular breast tissue (n = 10) were determined. A median cutoff of ≥ 15 defined patients with high numbers of TR.

Results

TR numbers were significantly higher in in situ and invasive breast carcinomas than in normal breast; invasive tumors have significantly higher numbers than DCIS (P = .001). High numbers of FOXP3-positive TR identified patients with DCIS at increased risk of relapse (P = .04) and patients with invasive tumors with both shorter relapse-free (P = .004) and overall survival (P = .007). High TR numbers were present in high-grade tumors (P ≤ .001), in patients with lymph node involvement (P = .01), and in estrogen receptor (ER) –negative tumors (P = .001). Importantly, high numbers of TR within ER-positive tumors identified high-risk patients (P = .005). Unlike conventional clinicopathologic factors, high numbers of FOXP3-positive TR can identify patients at risk of relapse after 5 years.

Conclusion

These findings indicate that quantification of FOXP3-positive TR in breast tumors is valuable for assessing disease prognosis and progression, and that TR are an important therapeutic target for breast cancer. FOXP3-positive TR represent a novel marker for identifying late-relapse patients who may benefit from aromatase therapy after standard tamoxifen treatment.
Phase III Trial Comparing Supportive Care Alone With Supportive Care With Oral Topotecan in Patients With Relapsed Small-Cell Lung Cancer
Authors: O'Brien Mary E.R. , Ciuleanu Tudor-Eliade , Tsekov Hristo , Shparyk Yaroslav , Čučeviá Branka , Juhasz Gabor , Thatcher Nicholas , Ross Graham A. , Dane Graham C. , Crofts Theresa
Published: November 2006

Purpose

For patients with small-cell lung cancer (SCLC), further chemotherapy is routinely considered at relapse after first-line therapy. However, proof of clinical benefit has not been documented.

Patients and Methods

This study randomly assigned patients with relapsed SCLC not considered as candidates for standard intravenous therapy to best supportive care (BSC) alone (n = 70) or oral topotecan (2.3 mg/m2/d, days 1 through 5, every 21 days) plus BSC (topotecan; n = 71).

Results

In the intent-to-treat population, survival (primary end point) was prolonged in the topotecan group (log-rank P = .0104). Median survival with BSC was 13.9 weeks (95% CI, 11.1 to 18.6) and with topotecan, 25.9 weeks (95% CI, 18.3 to 31.6). Statistical significance for survival was maintained in a subgroup of patients with a short treatment-free interval (≤ 60 days). Response to topotecan was 7% partial and 44% stable disease. Patients on topotecan had slower quality of life deterioration and greater symptom control. Principal toxicities with topotecan were hematological: grade 4 neutropenia, 33%; grade 4 thrombocytopenia, 7%; and grade 3/4 anemia, 25%. Comparing topotecan with BSC, infection ≥ grade 2 was 14% versus 12% and sepsis 4% versus 1%; other grade 3/4 events included vomiting 3% versus 0, diarrhea 6% versus 0, dyspnea 3% versus 9%, and pain 3% versus 6%. Toxic deaths occurred in four patients (6%) in the topotecan arm. All cause mortality within 30 days of random assignment was 13% on BSC and 7% on topotecan.

Conclusion

Chemotherapy with oral topotecan is associated with prolongation of survival and quality of life benefit in patients with relapsed SCLC.
A Simple and Innovative Device to Measure Arm Volume at Home for Patients With Lymphedema After Breast Cancer
Authors: Lette Jean
Published: November 2006

Purpose

We designed an arm volumeter specifically for home use based on the water displacement method. The objective of this study was to determine its accuracy and precision, and compare it with a standard volumeter used in lymphedema clinics worldwide.

Patients and Methods

Using a standard model hospital volumeter and our own device, we took three consecutive measurements of 11 specially cast cylinders, which had known volumes ranging from 10mL to 4 L, and measurements of both arms of 15 volunteers.

Results

Measurements with both volumeters were highly accurate (R2 = 0.9999) when compared with the known volumes of the cast cylinders, and were strongly correlated (R2 = 0.9974) when each arm volume was compared between volumeters. Measurements with our volumeter were more precise both with the cylinders (average standard deviation [SD], 3.2 v 8 mL; P = .0553) and with the arms (average SD, 11.1 v 19 mL; P = .0034). Whereas the standard volumeter is expensive, fragile (acrylic), and prone to leaks, our volumeter is inexpensive, virtually indestructible, leak proof, and suitable for home use.

Conclusion

Arm volumes can be measured quickly and accurately at home using a simple, inexpensive, and robust device based on water displacement. Readily accessible arm volumetry at home may have widespread influence on the management of lymphedema after breast cancer.
Detrimental Effects of Tumor Progression on Cognitive Function of Patients With High-Grade Glioma
Authors: Brown Paul D. , Jensen Ashley W. , Felten Sara J. , Ballman Karla V. , Schaefer Paul L. , Jaeckle Kurt A. , Cerhan Jane H. , Buckner Jan C.
Published: November 2006

Purpose

There is growing recognition that the primary cause of cognitive deficits in adult patients with primary brain tumors is the tumor itself and more significantly, tumor progression. To assess the cognitive performance of high-grade glioma patients, prospectively collected cognitive performance data were analyzed.

Patients and Methods

We studied 1,244 high-grade brain tumor patients entered onto eight consecutive North Central Cancer Treatment Group treatment trials that used radiation and nitrosourea-based chemotherapy. Imaging studies and Folstein Mini-Mental State Examination (MMSE) scores recorded at baseline, 6, 12, 18, and 24 months were analyzed to assess tumor status and cognitive function over time.

Results

The proportion of patients without tumor progression who experienced clinically significant cognitive deterioration compared with baseline was stable at 6, 12, 18, and 24 months (18%, 16%, 14%, and 13%, respectively). In patients without radiographic evidence of progression, clinically significant deterioration in MMSE scores was a strong predictor of a more rapid time to tumor progression and death. At evaluations preceding interval radiographic evidence of progression, there was significant deterioration in MMSE scores for patients who were to experience progression, whereas the scores remained stable for the patients who did not have tumor progression.

Conclusion

The proportion of high-grade glioma patients with cognitive deterioration over time is stable, most consistent with the constant pressure of tumor progression over time. Although other factors may contribute to cognitive decline, the predominant cause of cognitive decline seems to be subclinical tumor progression that precedes radiographic changes.
Intelligent intraoral drug delivery microsystem
Authors: Velten T , Schuck H , Knoll T , Scholz O , Schumacher A , Göttsche T , Wolff A , Beiski B Z , Consortium IntelliDrug
Published: November 2006

The authors report on the concept and development of an intelligent intraoral drug delivery microsystem, that provides an alternative approach for the treatment of addiction and chronic diseases. The drug delivery system (DDS) comprises a medication replacement reservoir, a medication release mechanism, a built-in intelligence, a remote control, microsensors, and microactuators. It is thus able to release the medication in a controlled manner according to the patient needs.

The emphasis of this article is on the application of sensors and microfluidic components in a real microsystem and also showing some details of two system components, namely, the osmotic pump and the flow sensor. The motivation for the microfluidic approach, the concept of the DDS, the requirements for this specific application, and the arising problems will be presented and discussed. Regarding the sensors and actuators, the problems mainly concern size and power consumption. A major challenging aspect of microfluidic component development is to avoid clogging of small channels because of particles and recrystallization of saturated fluids.
Molecular mechanisms of synovial joint lubrication
Authors: Klein J
Published: November 2006

Current models for lubrication of synovial joints, and the nature of the cartilage surface, are briefly recalled. Direct friction studies between polymers attached to surfaces are then considered, particularly the very recent demonstration of extreme friction reduction enabled by hydrated ions and by charged polymers. It is proposed that the extremely efficient lubrication observed in living joints arises from the presence of a brush-like phase of charged macromolecules at the surface of the superficial zone. This phase forms when charged macromolecules, including lubricin, superficial-zone protein, and aggrecan, cross the interface between the superficial zone and the synovial cavity as they are secreted into the synovium from within the bulk of the cartilage, and, in particular, the feasibility of such brush-like surface-phases is examined in some detail. The molecular mechanisms for the reduction in friction are proposed to be similar to those recently revealed using surface force balance studies on lubrication by charged brushes.
The natural synovial joint: A finite element investigation of biphasic surface amorphous layer lubrication under dynamic loading conditions
Authors: Graindorge S , Ferrandez W , Jin Z-M , Ingham E , Fisher J
Published: November 2006

Despite much research, the lubrication mechanisms operating in healthy synovial joints, particularly in the boundary or mixed regimes, are still not clear. This work continued the previous research by the authors in using a finite element model to investigate the effect of a soft, biphasic, amorphous surface layer on the lubrication characteristics of articular cartilage. This model was extended and the ‘biphasic surface amorphous layer (SAL) effect’ was investigated under repetitive, dynamic loading conditions. The results of this model showed that the lubrication benefits and stress shielding conferred by the soft, biphasic SAL remained almost entirely effective, despite incomplete cartilage swelling during unloading. The reduction in friction and improved lubrication were shown to be more beneficial during rapid dynamic loading and adversely effected by slow, static loading. The very rapid recovery of the SAL was shown to play an essential role in the mechanism and was important in helping the tissue to sustain low friction under conditions of repeated dynamic loading.
Interactions between toothbrush and toothpaste particles during simulated abrasive cleaning
Authors: Lewis R , Dwyer-Joyce R. S.
Published: November 2006

Most people clean their teeth using toothpaste, consisting of abrasive particles in a carrier fluid, and a filament-based toothbrush to remove plaque and stain. In order to optimize cleaning efficiency, it is important to understand how toothbrush filaments, abrasive particles, and fluid interact in a tooth cleaning contact.

Work has been carried out to visualize, simulate, and model the processes in teeth cleaning. Laboratory cleaning contacts were created between a toothbrush and a transparent surface. Video and short-duration flash photography were used to study the processes by which a toothbrush traps abrasive particles, loads them against the counterface, and removes material. Small abrasive particles tend to be trapped at the contact between the filament tip and the counterface, while larger particles are trapped by clumps of filaments or at the contact with the side of a bent filament.

Measurements of brush friction force were recorded during cleaning for a range of operating conditions. The presence of abrasive particles in the cleaning mixture increased the coefficient of friction, but the absolute particle concentration showed a lesser effect. It is surmised that only a few particles carry any load and cause any abrasion; increasing the particle concentration does not directly increase the number of load bearing particles.

Abrasive scratch tests were also carried out, using polymethyl methacrylate (PMMA) as a wearing substrate. The scratches produced during these tests were studied. The microscopy images were used to deduce how the filaments deflect and drag, and how particles are trapped by filaments and scratch the surface. Again, it was observed that few of the brush filaments loaded particles to produce scratches, and that when a filament changes direction of travel the trapped particle is lost. Results of these studies were used to develop both qualitative and quantitative models of the process by which material is removed in teeth cleaning. The quantitative model contains, by necessity, several empirical factors, but nonetheless predictions compare well with in vitro wear results from the literature. The results were also used to draw some broad conclusions on appropriate brushing techniques for optimum tooth cleaning.
Regio- and Stereoselective Ring Opening of Epoxides and Aziridines Using Zirconyl Chloride: An Efficient Approach for the Synthesis of β-Chlorohydrins and β-Chloroamines
Authors: Das Biswanath , Krishnaiah Maddeboina , Venkateswarlu Katta
Published: November 2006

Zirconyl chloride mediated regio- and stereoselective ring opening of epoxides and aziridines at room temperature affords the corresponding β-chlorohydrins and β-chloroamines, respectively in high yields.
Preparation of a Carboxylate-binding Mononuclear Iron(II) (−)-Sparteine Complex with Structural Distortion and Its Reaction with Oxidants
Authors: Okumura Takeshi , Hayami Shinya , Ozawa Tomohiro , Funahashi Yasuhiro , Maeda Yonezo , Masuda Hideki
Published: November 2006

A novel iron complex with a distorted coordination geometry, [FeII((−)-sp)(OBz)2] (1) ((−)-sp = (−)-sparteine, OBz = benzoate anion), was prepared and structurally characterized by X-ray analysis. The stoichiometric reaction of 1 and mCPBA (m-chloroperbenzoic acid) degraded EtCN to CN− and CH3CHO. In CH2Cl2, a very short-lived intermediate species was generated, exhibiting an intense absorption band at 420 nm (ε ≈ 2000 M−1·cm−1) and a weak absorption band at 870 nm (ε ≈ 100 M−1·cm−1).
The position of yeast snoRNA-coding regions within host introns is essential for their biosynthesis and for efficient splicing of the host pre-mRNA
Authors: Vincenti Sara , De Chiara Valentina , Bozzoni Irene , Presutti Carlo
Published: November 2006

Genomic location of sequences encoding small nucleolar RNAs (snoRNAs) is peculiar in all eukaryotes from yeast to mammals: most of them are encoded within the introns of host genes. In Saccharomyces cerevisiae, seven snoRNAs show this location. In this work we demonstrate that the position of snoRNA-coding regions with respect to splicing consensus sequences is critical: yeast strains expressing mutant constructs containing shorter or longer spacers (the regions between snoRNA ends and intron splice sites) show a drop in accumulation of U24 and U18 snoRNAs. Further mutational analysis demonstrates that altering the distance between the 3′ end of the snoRNA and the branch point is the most important constraint for snoRNA biosynthesis, and that stable external stems, which are sometimes present in introns containing snoRNAs, can overcome the positional effect. Surprisingly enough, splicing of the host introns is clearly affected in most of these constructs indicating that, at least in S. cerevisiae, an incorrect location of snoRNA-coding sequences within the host intron is detrimental to the splicing process. This is different with respect to what was demonstrated in mammals, where the activity of the splicing machinery seems to be dominant with respect to the assembly of snoRNPs, and it is not affected by the location of snoRNA sequences. We also show that intronic box C/D snoRNA recognition and assembly of snoRNPs occur during transcription when splicing sequences are recognized.
Level of Operator Control and Changes in Heart Rate Variability during Simulated Flight Maintenance
Authors: Tattersall Andrew J. , Hockey G. Robert J.
Published: November 2006

The demands of dynamic monitoring and fault diagnosis for flight engineer trainees were examined in relation to changes in heart rate (HR) and two spectral analysis measures (midfrequency: 0.07-0.14 Hz; high frequency: 0.15-0.40 Hz) of heart rate variability (HRV). Eleven trainee flight engineers were studied, as part of their training and assessment, over three 3-h sessions in a cockpit simulator. During each session, faults and incidents programmed into the system had to be detected, diagnosed, and corrected. Electrocardiograms were taken, and each session was recorded on videotape. Work phases were classified from video analysis of flight maintenance activities, using Rasmussen's cognitive control taxonomy, into monitoring, routine (rule-based), and problem-solving (knowledge-based) phases. HR and HRV were found to be sensitive to different phases of the work environment. HRV was suppressed during the mentally demanding problemsolving mode of the level flight phase, but only for the midfrequency component. Elevated heart rate, in contrast, was associated with the more generally stressful takeoff and landing phases. The findings support both the use of HRV as a physiological index of mental effort and its value in operational contexts, and the value of ecologically derived methods of evaluating differences in work demands in complex systems.
Symmetric and Asymmetric Two-Handed Pull-Push Strength of Young Adults
Authors: Kumar Shrawan , Narayan Yogesh , Bacchus Chris
Published: November 2006

Forty normal young adults volunteered for an experiment in which they were required to perform two-handed maximal pull-push in isometric and isokinetic modes (50 cm/s linear velocity of the handle) at 50-, 100-, and 150-cm heights of handle in sagittal, 30-deg lateral, and 60-deg lateral planes. Subjects were stabilized on a circular platform that rotated on its axis and allowed fixation in any position to achieve asymmetric settings. The pull-push strengths were applied to a 53-cm wide handle and were measured through the load cell assembly of the Static Dynamic Strength Tester. The peak and average strengths were compared statistically, and an ANOVA and multiple regression were performed. The main effects of gender, activity (pull or push), mode (isometric or isokinetic), plane (sagittal, 30 deg lateral, or 60 deg lateral), and height (low, medium, or high) of activity for both peak and average strengths were highly significant ( p < 0.01). All subjects were strongest in pulling activity in the isometric mode in the sagittal plane at medium height. Males were significantly stronger than females for most activities. However, with increased postural asymmetry, the difference between genders declined.
Measuring Knowledge Organization as a Method for Assessing Learning during Training
Authors: Kraiger Kurt , Salas Eduardo , Cannon-Bowers Janis A.
Published: November 2006

This paper applies the conceptual work of K. Kraiger, J. K. Ford, and E. Salas (1993) to the evaluation of two training programs. A method known as structural assessment (SA) was described and adapted for use in the evaluation of a training program for computer programming and a PC-based simulation of a naval decision-making task. SA represents and evaluates pairwise judgments of relatedness of concepts drawn from the training content domain. In the first study, SA scores of students (determined by similarity to an expert solution) were significantly higher after training than before but did not predict performance on a take-home exam 12 weeks later. In the second study, we manipulated training content by providing half the students with the goals and objectives of the transfer task (an advance organizer) before training and providing the other half with the same information after training. As hypothesized, SA scores were higher for those receiving the organizers before training; SA scores were also more strongly related to performance on the criterion task for this group. Implications of the results for training evaluation are discussed.
Oculomotor Responses with Aviator Helmet-Mounted Displays and Their Relation to In-Flight Symptoms
Authors: Kotulak John C. , Morse Stephen E.
Published: November 2006

Previous experiments have raised the possibility that abnormal oculomotor functioning could be the substrate for visual problems among aviators who use helmetmounted displays. However, until the present investigation. no direct evidence linked the two. In our experiments, experienced Apache helicopter pilots. using the same helmet-mounted display that they use in flight. viewed Apache symbology and sensor imagery while we measured their accommodation and vergence eye movements in the laboratory. We found three circumstances that frequently occur in flight in which aviators with visual symptoms had different oculomotor responses than did asymptomatic aviators. Further work needs to be done to determine why symptomatic aviators respond differently from asymptomatic ones.
Practice Effects on Skill Acquisition, Learning Outcome, Retention, and Sensitivity to Relearning
Authors: Shute Valerie J. , Gawlick Lisa A.
Published: November 2006

This paper presents the results from two experiments that examined practice effects on skill acquisition, learning outcome, retention, and sensitivity to relearning. In Experiment 1, our learning criterion task was an intelligent tutoring system teaching flight engineering knowledge and skills. The system was divided into two main curriculum sections, with two practice conditions per section: abbreviated and extended. Thus there were a total of four practice conditions differing only in the number of practice problems requiring solution across problem sets. Experiment 1 showed that subjects in the more abbreviated conditions completed the curriculum significantly faster than did subjects in more extended conditions, but at the expense of greater errors and latencies during problem solution within the tutor. Despite these acquisition differences, groups performed the same across all learning outcome measures. Experiment 2 examined the effects of practice condition on retention and sensitivity to relearning after two years. Although the sample size was fairly small (34 returning subjects), we found evidence for practice effects on long-term retention but not in the predicted direction. In terms of our sensitivity to relearning measure, the groups did not differ. Implications of these findings for optimizing training are discussed.
Effect of Lifting Belts, Foot Movement, and Lift Asymmetry on Trunk Motions
Authors: Lavender Steven A. , Thomas James S. , Chang Dennis , Andersson Gunnar B. J.
Published: November 2006

Whether or not lifting belts protect workers from injury is a topic of considerable interest in industry. Not only is the protective effect uncertain, but the biomechanical basis for belt function is unclear. The objective of this study was to determine if lifting belts provide a means for controlling trunk motions during asymmetric material-handling tasks. We recruited 16 nursing personnel as experienced lifters to participate in two lifting sessions. A lifting belt was worn in one session and for a week prior to this session during the subjects' routine work activities. Each session required 42 lifts, distributed across three asymmetry conditions (0, 45, and 90 deg) and temporally spaced 30 s apart. Foot motion was not permitted in half the lifts. Results indicated that during lifting, lateral bending and twisting motions were reduced by both the lifting belt and foot motion; the most pronounced effect was observed at 90 deg of asymmetry. Trunk motions in the sagittal plane during lifting were not affected by the lifting belt. These results appear to support the use of lifting belts in asymmetric lifting conditions, but more research is needed to determine whether the muscles in the torso benefit from the reduced motion or are working harder to overcome this resistance to motion, causing increased internal loads on the spine during asymmetric material-handling tasks.
Visual Arithmetic, Computational Graphics, and the Spatial Metaphor
Authors: Gillan Douglas J.
Published: November 2006

People who interact with graphs to perform arithmetic tasks typically employ quantitative features. However, they may employ the spatial metaphor under two alternative conditions: if they have been trained to apply visual arithmetic methods to traditional line and bar graphs, or if they interact with specially constructed and special-purpose computational graphics. Two experiments explored a visual arithmetic method used to train subjects to determine a mean by locating the spatial midpoint of a set of indicators (bars in a bar graph or points in a line graph). In Experiment 1 visual arithmetic subjects determined the mean of five indicators as quickly as they did the mean of two indicators; control subjects performed slower with five indicators. Both groups took more time to add the values of five indicators than to add two indicators. In Experiment 2, unlike control subjects, visual arithmetic subjects' response times in mean trials were unaffected by changes in the y-axis scale. However, both groups were affected by the y-axis scale on addition trials. Neither group was influenced by changes in the distance between indicators. The discussion addresses the transfer of visual arithmetic training to tasks that differ from the one used during training, uses for visual arithmetic and computational graphics, and the role of parallel processing and task restructuring in visual arithmetic.
Effects of Frequency on Free-Field Masking
Authors: Gilkey Robert H. , Good Michael D.
Published: November 2006

As three-dimensional auditory displays become more prevalent, there will be an increasing need to understand the interactions that can be expected among spatially separated sounds. A two-alternative, forced-choice, adaptive staircase procedure was used to measure the detectability of a 165-ms click-train signal masked by a continuous Gaussian noise, as a function of the spatial separation between the signal and the masker in the free field. Horizontal separations within the horizontal plane and vertical separations within the median plane were examined for low-, mid-, and high-frequency stimuli. Masking was reduced by as much as 18 dB when the signal and masker were separated horizontally. Sizable reductions in masking (6-9 dB) were also observed for vertical separation. The largest reductions in masking were observed for the high-frequency stimuli. The data are compared with the results of headphone-based studies of binaural masking. Implications for the design of auditory displays are considered.
Dual-Task Performance in Space: Results from a Single-Case Study during a Short-Term Space Mission
Authors: Manzey Dietrich , Lorenz Bernd , Schiewe Albrecht , Finell Georg , Thiele Gerhard
Published: November 2006

During spaceflights, astronauts are exposed to many stressors (e.g., microgravity, confinement) that may impair human information-processing capabilities. In order to analyze the possible effects of the space environment on human timesharing efficiency, a single-case experiment was conducted in which the time course of dual-task performance (unstable tracking with concurrent memory search) of one space crew member was monitored repeatedly (13 times) throughout an 8-day space mission. Tasks were taken from the Advisory Group for Aerospace Research and Development battery of Standardized Tests for Research with Environmental Stressors. Comparisons of in-flight, preflight, and postflight performance revealed no decrements in single-task memory search performance but did reveal clear impairments in single-task tracking and dual-task performance. From these results we conclude that psychomotor processes and higher attentional functions are particularly prone to disturbance effects in space.
Visual Scene Properties Relevant for Simulating Low-Altitude Flight: A Multidimensional Scaling Approach
Authors: Kleiss James A.
Published: November 2006

In the present experiments I sought to identify the properties of visual scenes relevant for simulating low-altitude flight. The approach was first to identify the relevant properties of real-world scenes. The stimuli were videotape segments or still photographs of real-world scenes exhibiting a variety of scene properties. Ratings of similarity between stimulus pairs were submitted to multidimensional scaling analyses. Results using videotape segments provided consistent evidence for two relevant scene properties: variation in terrain shape and variation in object size or spacing. Results using still photographs were less interpretable, supporting the argument that motion information is important. Results suggest that designers of flight simulator visual scenes should focus specifically on rendering elements of terrain shape and objects in scenes.
Effects of Instruction Type and Boredom Proneness in Vigilance: Implications for Boredom and Workload
Authors: Sawin David A. , Scerbo Mark W.
Published: November 2006

The present study examined the effects of instruction type and boredom proneness (BP) on vigilance performance, workload, and boredom. Subjects completed the Boredom Proneness Scale and were assigned to high and low groups based on their scores. They then monitored a VDT for critical signals. Half the subjects were instructed to detect “critical” flickers (detection emphasis), and the remaining subjects were instructed to relax but to respond to any flickers observed (relaxation emphasis). Subjects also provided pre- and postvigil ratings of workload, stress, and boredom. A performance decrement was observed for all conditions. Low-BP subjects outperformed high-BP subjects and reported less boredom. Thus the results from the present study provide evidence for the long-sought, elusive link between trait boredom and performance in vigilance. In addition, subjects who received relaxation-emphasis instructions reported lower workload, frustration, and stress for the vigil than did those receiving detection-emphasis instructions. These results are discussed in terms of a recent dynamic model of stress as it relates to sustained attention.
Effect of Background Scene Complexity and Field Dependence on the Legibility of Head-Up Displays for Automotive Applications
Authors: Ward Nicholas J. , Parkes Andrew , Crone Peter R.
Published: November 2006

This study examined the legibility of information presented on head-up displays (HUDs) for automotive application as a function of background scene complexity, the position of the HUD within field of view relative to the background scene, and the perceptual capacity of the perceiver. Groups of field-dependent and fieldindependent subjects viewed video footage from the perspective of following a lead caron an open road with low, moderate, and high scene complexity. Subjects were required to track the lead vehicle and identify HUD-presented targets of a specified orientation and specified changes in a HUD-presented speedometer. The results indicate that (a) HUD legibility deteriorated with increased visual complexity of the background scene; (b) positioning the HUD on the roadway reduced the effect of background scene complexity on HUD legibility; and (c) field-dependent subjects made fewer correct and more false positive target identifications than did field-independent subjects.
Selecting System Functionalities for Interface Evaluation
Authors: Mitta Deborah A. , Delk Catherine M. , Lively William M.
Published: November 2006

Software developers are frequently required to evaluate the usability of produces they design. Limited resources often prevent them from performing a complete interface evaluation prior to product release. In these instances a relatively standard approach is to identify a few functionalities on which to focus evaluation efforts. This paper proposes a three-phased methodology for selecting this “short list” of functionalities. In Phase 1 a functional-level goals, operator., methods, selection rules (GOMS) model representing required user-system interaction tasks is developed. In Phase 2 functionalities are identified, which serve as candidates for evaluation. Task descriptions developed during the initial phase facilitate completion of Phase 2. In Phase 3 the functionality short list is derived. The methodology is applied to the Information Engineering FacilityTM, a computer-aided software engineering tool developed by Texas Instruments. Implications of implementing the methodology are discussed.
SHORT NOTE: Field Evaluation of an Advance Brake Warning System
Authors: Shinar David
Published: November 2006

A field study was conducted to evaluate an advance brake warning (ABW) light activation system. The ABW system detects very rapid accelerator pedal releases (assumed to characterize contingent braking responses) and activates the brake light. If the driver brakes within 1.0 s, then continuation of the brake light is governed by the brake pedal. Otherwise the light goes off. The ABW system was installed on six vehicles driven by their regular users, who were unaware of the system or the study. A total of 61 668 km were driven, in which the drivers braked 95394 times. The ABW system was activated on 820 of those occasions, providing the following driver a 0.22 s warning. It was determined that the emergency braking activating the ABW system is relatively rare, occurring on average 13.3 times per 1000 km and less than 1% of all brake actions. False alarms (ABW activation without braking) occurred in 23% of all ABW activations but were insignificant (1 in 50) relative to the total number of brief braking actions lasting less than 1.0 s. It therefore appears that the advance brake warning light can provide the intended information without being a safety hazard to following drivers.
Criterion Test for Method Selection in Determining the Bulk Specific Gravity of Hot-Mix Asphalt
Authors: Williams BA , Bausano JP , Williams RC
Published: November 2006

A number of test methods are available to measure the bulk specific gravity of compacted hot-mix asphalt (HMA). The most commonly used test method, ASTM D 2726 [1], was designed for use with specimens that do not contain open or interconnected air voids such as dense-graded HMA mixtures. Coarse and open-graded HMA mixes are known for their open or interconnected void space. The current method for addressing coarse and open-graded mixes, ASTM D 1188 [2], can lead to erroneous bulk specific gravity measurements. Thus a nondestructive vacuum sealing method (ASTM D 6752) [3] was developed to address HMA mixtures that contain open or interconnected air voids. The objective of this research is to define the point at which the vacuum sealing method (ASTM D 6752) [3] more accurately measures the bulk specific gravity of an HMA specimen as compared to the conventional test (ASTM D 2726) [1] utilizing the saturated surface dry (SSD) method. Permeability (ASTM PS 129-01) [4] measures an HMA mixture's ability to allow moisture to pass through it, which in turn is related to the mixture's connectivity of void space. For this reason permeability was chosen as the fundamental property to investigate. ASTM PS 129-01 [4] is hypothesized as a criterion test for method selection in determining the appropriate bulk specific gravity test for coarse-graded HMA mixtures. One hundred and thirty-four field compacted roadway cores from 28 paving projects throughout the State of Michigan were evaluated using the vacuum sealing method and conventional SSD method of determining the bulk specific gravity of compacted HMA. These cores were then tested using a falling head permeability apparatus. It was determined that the bulk specific gravity of compacted HMA fine-graded mixes using the vacuum sealing method and conventional method are statistically the same. There is a difference in bulk specific gravity measurements when using the two bulk specific gravity tests on coarse-graded mixtures for roadway cores when the air void level is above 5.1 %. Thus the air void/permeability relationship was used to determine the coefficient of permeability at which the vacuum sealing method provides a more accurate measurement of the bulk specific gravity. This value was found to be 3.7×10-6 cm/s.
Hippocampal Sharp Waves and Reactivation during Awake States Depend on Repeated Sequential Experience
Authors: Jackson Jadin C. , Johnson Adam , Redish A. David
Published: November 2006

Hippocampal firing patterns during behavior are reactivated during rest and subsequent slow-wave sleep. These reactivations occur during transient local field potential (LFP) events, termed sharp waves. Theories of hippocampal processing suggest that sharp waves arise from strengthened plasticity, and that the strengthened plasticity depends on repeated cofiring of pyramidal cells. We tested these predictions by recording neural ensembles and LFPs from rats running tasks requiring different levels of behavioral repetition. The number of sharp waves emitted increased during sessions with more regular behaviors. Reactivation became more similar to behavioral firing patterns across the session. This enhanced reactivation also depended on the regularity of the behavior. Additional studies in CA3 and CA1 found that the number of sharp waves emitted also increased in CA3 recordings as well as CA1, but that the time courses were different between the two structures.
Net topologies, space groups, and crystal phases
Authors: Thimm Georg , Winkler Björn
Published: November 2006

Quotient graphs and nets — the graph theore tical correspondences of cells and crystal structures — are reintroduced independent from crystal structures. Based on this, the issue of iso- and automorphism of nets, the graph theoretical equivalent of symmetry operations, is closely examined. A result, it is shown that the topology of a net (that is the bonds in a crystal) constrains severely the symmetry of the embedding (that is the crystal), and in the case of connected nets the space group except for the setting. Several examples are studied and conclusions on phases are drawn (pseudo-cubic FeS2
versus pyrite; α-versus
β-quartz; marcasite-versus rutile-like phases).
Posttournament Survival and Dispersal of Adult Striped Bass
Authors: Young Shawn P. , Isely J. Jeffery
Published: November 2006

We conducted a telemetry study from November 2004 to June 2005 at J. Strom Thurmond Reservoir in South Carolina and Georgia to quantify posttournament survival of striped bass and their dispersal from tournament weigh-in sites. During November–December 2004, 30 adult striped bass weighing 1.0–10.0 kg were angled, held in “striped bass tube” live-holding systems for 2–5 h, transported to a predetermined weigh-in and release site, and surgically implanted with telemetry transmitters. All striped bass survived transport, recovered from the surgical procedure, and were immediately released. The postrelease survival rate after 120 d was 87%. Surviving striped bass dispersed from the release site within 2–9 d. Fifty-four percent returned to their capture sites. Capture, holding, displacement, and weigh-in appeared to have no long-term adverse affects on behavior. Live release of striped bass may now be a viable option after tournaments during periods of cool water temperatures.
Effects of Wildfire and Subsequent Hydrologic Events on Fish Distribution and Abundance in Tributaries of North Fork John Day River
Authors: Howell Philip J.
Published: November 2006

Recent large wildfires in western states have fueled increasing concerns of resource managers and the public about the effects of fire, including risks to fish, particularly endangered species. However, there are few empirical studies on the response of fish to fire and none that include anadromous species. The Tower Fire was one of four large fires in the upper John Day River basin in Oregon in 1996. Much of the area burned at moderate to high severity, consistent with the pattern of increasing fire severity and size projected for the region. Intense spring storms in 1997 and 1998 triggered large floods, landslides, and debris torrents that affected streams within and downstream of the fire. We investigated the effects of the fire and ensuing floods on fish distribution and abundance in three streams immediately after the fire through 2003. Immediately after the fire, no fish were found in moderate- and high-intensity burn areas. Fish began to repopulate defaunated reaches the year after the fire, and within 4 years distribution of juvenile steelhead (anadromous rainbow trout Oncorhynchus mykiss) and resident rainbow trout was similar to that before the fire. Juvenile spring Chinook salmon O. tshawytscha also began to use lower reaches of one of the streams after the flood, which had eliminated a culvert near the mouth of the stream suspected to be a barrier. Densities in most burned reaches and in unburned reaches downstream of the fire have rebounded to levels similar to or greater than densities in reference streams outside of the fire. An isolated introduced population of brook trout Salvelinus fontinalis also recovered. Thus, despite the size and severity of the fire, postfire hydrologic events, and human-induced changes to watersheds, fish populations were highly resilient.
Random versus Fixed-Site Sampling When Monitoring Relative Abundance of Fishes in Headwater Streams of the Upper Colorado River Basin
Authors: Quist Michael C. , Gerow Kenneth G. , Bower Michael R. , Hubert Wayne A.
Published: November 2006

Native fishes of the upper Colorado River basin (UCRB) have declined in distribution and abundance due to habitat degradation and interactions with nonnative fishes. Consequently, monitoring populations of both native and nonnative fishes is important for conservation of native species. We used data collected from Muddy Creek, Wyoming (2003–2004), to compare sample size estimates using a random and a fixed-site sampling design to monitor changes in catch per unit effort (CPUE) of native bluehead suckers Catostomus discobolus, flannelmouth suckers C. latipinnis, roundtail chub Gila robusta, and speckled dace Rhinichthys osculus, as well as nonnative creek chub Semotilus atromaculatus and white suckers C. commersonii. When one-pass backpack electrofishing was used, detection of 10% or 25% changes in CPUE (fish/100 m) at 60% statistical power required 50–1,000 randomly sampled reaches among species regardless of sampling design. However, use of a fixed-site sampling design with 25–50 reaches greatly enhanced the ability to detect changes in CPUE. The addition of seining did not appreciably reduce required effort. When detection of 25–50% changes in CPUE of native and nonnative fishes is acceptable, we recommend establishment of 25–50 fixed reaches sampled by one-pass electrofishing in Muddy Creek. Because Muddy Creek has habitat and fish assemblages characteristic of other headwater streams in the UCRB, our results are likely to apply to many other streams in the basin.