bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling marine protected areas for threatened eiders in a climatically changing Bering Sea
Authors: Lovvorn James R. , Grebmeier Jacqueline M. , Cooper Lee W. , Bump Joseph K. , Richman Samantha E.
Published: August 2009

Delineating protected areas for sensitive species is a growing challenge as changing climate alters the geographic pattern of habitats as well as human responses to those shifts. When human impacts are expected within projected ranges of threatened species, there is often demand to demarcate the minimum habitat required to ensure the species' persistence. Because diminished or wide‐ranging populations may not occupy all viable (and needed) habitat at once, one must identify thresholds of resources that will support the species even in unoccupied areas. Long‐term data on the shifting mosaic of critical resources may indicate ranges of future variability. We addressed these issues for the Spectacled Eider (Somateria fischeri), a federally threatened species that winters in pack ice of the Bering Sea. Changing climate has decreased ice cover and severely reduced the eiders' benthic prey and has increased prospects for expansion of bottom trawling that may further affect prey communities. To assess long‐term changes in habitats that will support eiders, we linked data on benthic prey, sea ice, and weather from 1970 to 2001 with a spatially explicit simulation model of eider energy balance that integrated field, laboratory, and remote‐sensing studies. Areas estimated to have prey densities adequate for eiders in 1970–1974 did not include most areas that were viable 20 years later (1993–1994). Unless the entire area with adequate prey in 1993–1994 had been protected, the much reduced viable area in 1999–2001 might well have been excluded. During long non‐foraging periods (as at night), eiders can save much energy by resting on ice vs. floating on water; thus, loss of ice cover in the future might substantially decrease the area in which prey densities are adequate to offset the eiders' energy needs. For wide‐ranging benthivores such as eiders, our results emphasize that fixed protected areas based on current conditions can be too small or inflexible to subsume long‐term shifts in habitat conditions. Better knowledge of patterns of natural disturbance experienced by prey communities, and appropriate allocation of human disturbance over seasons or years, may yield alternative strategies to large‐scale closures that may be politically and economically problematic.
Predicting declines in avian species richness under nonrandom patterns of habitat loss in a Neotropical landscape
Authors: Rompré Ghislain , Robinson W. Douglas , Desrochers André , Angehr George
Published: August 2009

One of the key concerns in conservation is to document and predict the effects of habitat loss on species richness. To do this, the species–area relationship (SAR) is frequently used. That relationship assumes random patterns of habitat loss and species distributions. In nature, however, species distribution patterns are usually nonrandom, influenced by biotic and abiotic factors. Likewise, socioeconomic and environmental factors influence habitat loss and are not randomly distributed across landscapes. We used a recently developed SAR model that accounts for nonrandomness to predict rates of bird species loss in fragmented forests of the Panama Canal region, an area that was historically covered in forest but now has 53% forest cover. Predicted species loss was higher than that predicted by the standard SAR. Furthermore, a species loss threshold was evident when remaining forest cover declined by 25%. This level of forest cover corresponds to 40% of the historical forest cover, and our model predicts rapid species loss past that threshold. This study illustrates the importance of considering patterns of species distributions and realistic habitat loss scenarios to develop better estimates of losses in species richness. Forecasts of tropical biodiversity loss generated from simple species–area relationships may underestimate actual losses because nonrandom patterns of species distributions and habitat loss are probably not unique to the Panama Canal region.
When can efforts to control nuisance and invasive species backfire?
Authors: Zipkin Elise F. , Kraft Clifford E. , Cooch Evan G. , Sullivan Patrick J.
Published: August 2009

Population control through harvest has the potential to reduce the abundance of nuisance and invasive species. However, demographic structure and density‐dependent processes can confound removal efforts and lead to undesirable consequences, such as overcompensation (an increase in abundance in response to harvest) and instability (population cycling or chaos). Recent empirical studies have demonstrated the potential for increased mortality (such as that caused by harvest) to lead to overcompensation and instability in plant, insect, and fish populations. We developed a general population model with juvenile and adult stages to help determine the conditions under which control harvest efforts can produce unintended outcomes. Analytical and simulation analyses of the model demonstrated that the potential for overcompensation as a result of harvest was significant for species with high fecundity, even when annual stage‐specific survivorship values were fairly low. Population instability as a result of harvest occurred less frequently and was only possible with harvest strategies that targeted adults when both fecundity and adult survivorship were high. We considered these results in conjunction with current literature on nuisance and invasive species to propose general guidelines for assessing the risks associated with control harvest based on life history characteristics of target populations. Our results suggest that species with high per capita fecundity (over discrete breeding periods), short juvenile stages, and fairly constant survivorship rates are most likely to respond undesirably to harvest. It is difficult to determine the extent to which overcompensation and instability could occur during real‐world removal efforts, and more empirical removal studies should be undertaken to evaluate population‐level responses to control harvests. Nevertheless, our results identify key issues that have been seldom acknowledged and are potentially generic across taxa.
Climate alters response of an endemic island plant to removal of invasive herbivores
Authors: McEachern A. Kathryn , Thomson Diane M. , Chess Katherine A.
Published: August 2009

Islands experience higher rates of species extinction than mainland ecosystems, with biological invasions among the leading causes; they also serve as important model systems for testing ideas in basic and applied ecology. Invasive removal programs on islands are conservation efforts that can also be viewed as powerful manipulative experiments, but few data are available to evaluate their effects. We collected demographic and herbivore damage data for Castilleja mollis Pennell, an endangered plant endemic to Santa Rosa Island, California, over a 12‐year period before, during, and after the implementation of control for introduced cattle, deer, and elk. We used these long‐term data to explore mechanisms underlying herbivore effects, assess the results of herbivore reduction at the scales of both individual plants and populations, and determine how temporal variability in herbivory and plant demography influenced responses to herbivore removals. For individual plants, herbivore effects mediated by disturbance were greater than those of grazing. Deer and elk scraping of the ground substantially increased plant mortality and dormancy and reduced flowering and growth. Stem damage from browsing did not affect survivorship but significantly reduced plant growth and flower production. Herbivore control successfully lowered damage rates, which declined steeply between 1997 and 2000 and have remained relatively low. Castilleja mollis abundances rose sharply after 1997, suggesting a positive effect of herbivore control, but then began to decline steadily again after 2003. The recent decline appears to be driven by higher mean growing season temperatures; interestingly, not only reductions in scraping damage but a period of cooler conditions were significant in explaining increases in C. mollis populations between 1997 and 2002. Our results demonstrate strong effects of introduced herbivores on both plant demography and population dynamics and show that climate‐driven variation may counteract and mask positive responses to herbivore removal. Regional mean temperatures already have risen significantly over the last 50 years, suggesting that climate change could increasingly swamp the effects of management targeted at other environmental problems. Similar interactions between climate and invasive species will play an even greater role in future management, with long‐term data sets like this critical to quantifying such effects.
Assessing fuel treatment effectiveness using satellite imagery and spatial statistics
Authors: Wimberly Michael C. , Cochrane Mark A. , Baer Adam D. , Pabst Kari
Published: August 2009

Understanding the influences of forest management practices on wildfire severity is critical in fire‐prone ecosystems of the western United States. Newly available geospatial data sets characterizing vegetation, fuels, topography, and burn severity offer new opportunities for studying fuel treatment effectiveness at regional to national scales. In this study, we used ordinary least‐squares (OLS) regression and sequential autoregression (SAR) to analyze fuel treatment effects on burn severity for three recent wildfires: the Camp 32 fire in western Montana, the School fire in southeastern Washington, and the Warm fire in northern Arizona. Burn severity was measured using differenced normalized burn ratio (dNBR) maps developed by the Monitoring Trends in Burn Severity project. Geospatial data sets from the LANDFIRE project were used to control for prefire variability in canopy cover, fuels, and topography. Across all three fires, treatments that incorporated prescribed burning were more effective than thinning alone. Treatment effect sizes were lower, and standard errors were higher in the SAR models than in the OLS models. Spatial error terms in the SAR models indirectly controlled for confounding variables not captured in the LANDFIRE data, including spatiotemporal variability in fire weather and landscape‐level effects of reduced fire severity outside the treated areas. This research demonstrates the feasibility of carrying out assessments of fuel treatment effectiveness using geospatial data sets and highlights the potential for using spatial autoregression to control for unmeasured confounding factors.
Selective significance of genome size in a plant community with heavy metal pollution
Authors: Vidic T. , Greilhuber J. , Vilhar B. , Dermastia M.
Published: August 2009

In eukaryotes, nuclear genome sizes vary by more than five orders of magnitude. This variation is not related to organismal complexity, and its origin and biological significance are still disputed. One of the open questions is whether genome size has an adaptive role. We tested the hypothesis that genome size has selective significance, using five grassland communities occurring on a gradient of metal pollution of the soil as a model. We detected a negative correlation between the concentration of contaminating metals in the soil and the number of vascular plant species. Analysis of genome sizes of 70 herbaceous dicot perennial species occurring on the investigated plots revealed a negative correlation between the concentration of contaminating metals in the soil and the proportion of species with large genomes in plant communities. Consistent with the hypothesis, these results show that species with large genomes are at selective disadvantage in extreme environmental conditions.
Near‐surface remote sensing of spatial and temporal variation in canopy phenology
Authors: Richardson Andrew D. , Braswell Bobby H. , Hollinger David Y. , Jenkins Julian P. , Ollinger Scott V.
Published: August 2009

There is a need to document how plant phenology is responding to global change factors, particularly warming trends. “Near‐surface” remote sensing, using radiometric instruments or imaging sensors, has great potential to improve phenological monitoring because automated observations can be made at high temporal frequency. Here we build on previous work and show how inexpensive, networked digital cameras (“webcams”) can be used to document spatial and temporal variation in the spring and autumn phenology of forest canopies. We use two years of imagery from a deciduous, northern hardwood site, and one year of imagery from a coniferous, boreal transition site. A quantitative signal is obtained by splitting images into separate red, green, and blue color channels and calculating the relative brightness of each channel for “regions of interest” within each image. We put the observed phenological signal in context by relating it to seasonal patterns of gross primary productivity, inferred from eddy covariance measurements of surface–atmosphere CO2 exchange. We show that spring increases, and autumn decreases, in canopy greenness can be detected in both deciduous and coniferous stands. In deciduous stands, an autumn red peak is also observed. The timing and rate of spring development and autumn senescence varies across the canopy, with greater variability in autumn than spring. Interannual variation in phenology can be detected both visually and quantitatively; delayed spring onset in 2007 compared to 2006 is related to a prolonged cold spell from day 85 to day 110. This work lays the foundation for regional‐ to continental‐scale camera‐based monitoring of phenology at network observatory sites, e.g., National Ecological Observatory Network (NEON) or AmeriFlux.
Improving the Sequential Time Perception of Teenagers with Mild to Moderate Mental Retardation with 3D Immersive Virtual Reality (IVR)
Authors: Passig David
Published: August 2009

Children with mental retardation have pronounced difficulties in using cognitive strategies and comprehending abstract concepts—among them, the concept of sequential time (Van-Handel, Swaab, De-Vries, & Jongmans, 2007). The perception of sequential time is generally tested by using scenarios presenting a continuum of actions. The goal of this study was to test whether the perception of sequential time among teenagers with mental retardation would improve, by using an intervention program employing 3D Immersive Virtual Reality (IVR). Eighty-seven teenagers with mild to moderate mental retardation, between the ages of 9 to 21, participated in the study. They were divided into three groups: a) an experimental group, who experienced sequential time scenarios in 3D IVR; b) one control group, who experienced the same scenarios via a series of two-dimensional (2D) pictorial episodes; and c) a second control group, who underwent no program of intervention. Our findings indicate that the participants who used the IVR program improved their time perception more than did the other members of the two control groups. In addition, the results reveal that the achievement required less moderation than executed with the control groups. Similarly, the results indicate that teens with mild retardation achieved a higher degree of sequential time perception than did those with moderate retardation.
The Effects of Lesson Screen Background Color on Declarative and Structural Knowledge
Authors: Clariana Roy B. , Prestera Gustavo E.
Published: August 2009

This experimental investigation replicates previous investigations of the effects of left margin screen background color hue to signal lesson sections on declarative knowledge and extends those investigations by adding a measure of structural knowledge. Participants ( N = 80) were randomly assigned to receive 1 of 4 computer-based lesson treatments that consisted of color or no color lessons crossed with color or no color structural knowledge and declarative knowledge posttests. A disordinal interaction was observed, lesson color had a significant positive effect on the structural knowledge posttest (effect size d = 0.41) but had a non-significant effect on the declarative knowledge posttest ( d = –0.17). A memory context effect was not observed. Designers of screen-based instructional materials should consider the commonsense notion that screen background color hues that signal lesson sections will tend to more strongly overlay the lesson organization onto the learner's memory organization.
A Look Inside a Muve Design Process: Blending Instructional Design and Game Principles To Target Writing Skills
Authors: Warren Scott J. , Stein Richard A. , Dondlinger Mary Jo , Barab Sasha A.
Published: August 2009

The number of games, simulations, and multi-user virtual environments designed to promote learning, engagement with subject matter, or intended to contextualize learning has been steadily increasing over the past decade. While the use of these digital designs in educational settings has begun to show promise for improving learning, motivation, and engagement as noted in studies of MIT Media Lab's Supercharged, Harvard University's River City, and Indiana University's Quest Atlantis, research reports have been unable to capture the design processes required to develop these complex instructional spaces. With the intention of illuminating one particular design process that met with some success, this article details the process of design and development that supported the creation of the language arts-focused Anytown multi-user virtual environment. The objective is to illustrate the complexity of taking an interactive digital learning environment from the planning phases through to the 3-D development of the environmental interactions and provide an example of how designers may match the media affordances present in games with instructional goals and principles that are intended to guide learning.
Development of an Electronic Version of the Homework Performance Questionnaire for Parents
Authors: Pendergast Laura L. , Watkins Marley W.
Published: August 2009

Homework is a standard, yet controversial, component of the American educational system. Unfortunately, research on parent perceptions of the efficacy of homework has been limited by a lack of reliable, valid measurement. The present study assessed the structural validity of an electronic version of a newly developed homework performance scale. Participants were 126 parents of students in a rural Illinois school district. A common factor analysis with principal axis extraction and promax rotation was employed. Three salient factors resulted: Student Task Engagement/Efficiency; Student Competence; and Teacher Support. These results indicate that scores on the electronic Homework Performance Questionnaire–Parent Scale (HPQ-PE) have a factor structure similar to the factor structure found previously with the paper-and-pencil version. Given these results, the HPQ-PE has the potential to become a useful tool for improving research on homework and informing the development of homework policies.
Learning to Teach Online: What Works for Pre-Service Teachers
Authors: Duncan Heather E. , Barnett John
Published: August 2009

While opportunities for online learning are increasing in K-12 education, few teacher education programs include courses on online teaching and learning. Using Garrison and Anderson's (2003) Community of Inquiry framework, this qualitative study explored the educational experiences of pre-service teachers in an experiential online course designed to teach about online teaching. Students explored aspects of online education and created a multi-media teaching module. The study highlighted the need for pre-service teacher education programs to design learning experiences that equip the next generation of teachers with the skills required to teach 21st century students in a variety of media that accommodate a diversity of learning styles.
Automated Modelling of Evolving Discontinuities
Authors: Nikbakht Mehdi , Wells Garth N.
Published: August 2009

The automated approximation of solutions to differential equations which involve discontinuities across evolving surfaces is addressed. Finite element technology has developed to the point where it is now possible to model evolving discontinuities independently of the underlying mesh, which is particularly useful in simulating failure of solids. However, the approach remains tedious to program, particularly in the case of coupled problems where a variety of finite element bases are employed and where a mixture of continuous and discontinuous fields may be used. We tackle this point by exploring the scope for employing automated code generation techniques for modelling discontinuities. Function spaces and variational forms are defined in a language that resembles mathematical notation, and computer code for modelling discontinuities is automatically generated. Principles underlying the approach are elucidated and a number of two- and three-dimensional examples for different equations are presented.
Biodegradability Evaluation of Polymers by ISO 14855-2
Authors: Funabashi Masahiro , Ninomiya Fumi , Kunioka Masao
Published: August 2009

Biodegradabilities of polymers and their composites in a controlled compost were described. Polycaprolactone (PCL) and poly(lactic acid) (PLA) were employed as biodegradable polymers. Biodegradabilities of PCL and PLA samples in a controlled compost were measured using a Microbial Oxidative Degradation Analyzer (MODA) according to ISO 14855-2. Sample preparation method for biodegradation test according to ISO/DIS 10210 was also described. Effects of sizes and shapes of samples on biodegradability were studied. Reproducibility of biodegradation test of ISO 14855-2 by MODA was confirmed. Validity of sample preparation method for polymer pellets, polymer film, and polymer products of ISO/DIS 10210 for ISO 14855-2 was confirmed.
Biocompatibility of Collagen Membranes Assessed by Culturing Human J111 Macrophage Cells
Authors: Aruta Claudia  Gaetana , Croce Maria  Antonietta , Quaglino Daniela , Guerra Deanna , Tiozzo Roberta
Published: August 2009

We have carried out an in vitro study on the interactions of human macrophages (J111 cell line) with different scaffolds made of type I and II collagen, isolated from horse tendon and from horse articular and trachea cartilage, in order to assess growth properties and biocompatibility of these membranes. We have therefore evaluated cell adhesion and proliferation as well as cytokine production considered an indicator of macrophage activation. The inflammatory response is in fact one of the major causes of collagen destruction thus interfering with cell and tissue behaviour. Moreover, the morphology of cells, seeded on membranes selected for the best characteristics, was described. Results might be relevant for in vivo application such ad “tissue engineering” and/or specialized cells implants.
ROV (Suijin)
Authors: Morrison Brody , Maillet Andrew , Brown Mac , Holloway Leslie , Moss Jade , Holloway Lindsay , Howse Danielle , White Michelle , Oldford Suyen , Young Jonathan , Chaffey Mark , Collins Shawn , Coles Michael , Penney Benji , Diamond Gavin
Published: August 2009

AbstractThe 2009 Marine Advanced Technology Education (MATE) remotely operated vehicle (ROV) competition focuses on a submarine rescue training exercise. There are four tasks outlined for the Ranger class, each providing
its own challenge. Our ROV was designed to carry out these tasks with precision and agility.The team spent numerous hours planning, building, and field testing our ROV. We had to be prepared to combat technical problems and overcome the challenge of differing opinions. Because of the diversity
of the tasks, Suijin had to be very well designed. This required the creation of a rigid frame, useful end effectors, and a versatile propulsion system; a form of buoyancy, effective sensors, and proper wiring were also necessary. There were many ideas to consider and obstacles to overcome,
but finally, we completed our masterpiece.Heritage Robotics is very pleased to present the following technical report, which communicates the details of Suijin, an ROV created by students from Heritage Collegiate, Lethbridge, Newfoundland, Canada. This document includes detailed
descriptions and diagrams of Suijin’s components, possible future improvements, trouble shooting techniques, the lessons we learned, the challenges we faced, information on the Submersible LR5, reflections, a thorough budget, and acknowledgments of all those who helped along the
way.
Joint Description Methods of Wind and Waves for the Design of Offshore Wind Turbines
Authors: Mittendorf Kim E.
Published: August 2009

AbstractWind and wave loads are equally important for the design of offshore wind energy structures. For the design against an ultimate limit state or fatigue, the engineer has to estimate the combination of loads that are likely to occur simultaneously during the design
life of the wind turbine. This is quite a complex task, involving different wind/wave models, load-calculation methods and statistical analysis of simultaneous extreme wind and wave conditions. Moreover, reliable and realistic methods for the assessment of the service life of an offshore wind
energy converter under combined wind and wave loads are necessary. However, the current design guidelines (Det Norske Veritas or German Lloyd) provide hardly any information on how to model the wind and wave correlation. In this article, several approaches for obtaining the required wind-wave
correlation for the design have been investigated. Manual wave forecasting methods, spectral sea state descriptions and numerical wave model data have been compared to simultaneously measured wind and wave data from the FINO research platform in the German Bight of the North Sea. The used
approaches are general and can be easily applied to different data sets from different regions.
Application of Multiple Attribute Decision-Making (MADM) and Analytical Hierarchy Process (AHP) Methods in the Selection Decisions for a Container Yard Operating System
Authors: Moghadam Mansoor Kiani , Bonsall Stephen , Wang Jin , Wall Alan
Published: August 2009

AbstractThis study examines and evaluates important parameters in container yard operating systems. The objective of this study is to set up a basis for decision-making to select the best scenario among other options. It examines the important attributes determined using
a multiple attribute decision-making (MADM) method. The MADM method is suited to the study of complex problems and allows the consideration of qualitative attributes expressed in linguistics terms and quantitative attributes illustrated in financial and throughput measures in container terminals.
An analytical hierarchy process (AHP) technique is employed for solving the MADM problems. The AHP and principal eigenvector weighting techniques have been proposed in this study as weighting tools because they allow decomposition of a decision problem into a hierarchical order and enable
a pair-wise comparison of the attributes with an acceptable level of consistency. The analysis assures that both qualitative and quantitative aspects of the decision are incorporated into the process. The results obtained from this study may be used to develop a basis for pair-wise comparison,
judgment and selection of the best container yard operation option for the purpose of this study. For the first time, this study proposes the application of MADM and AHP for selection decisions in container terminals.
The Detection of Annual Hypoxia in a Low Latitude Freshwater Reservoir in Kerala, India, Using the Small AUV Maya
Authors: Desa Elgar , Madhan R. , Maurya P. , Navelkar G. , Mascarenhas A. , Prabhudesai S. , Afzulpurkar S. , Desa Ehrlich , Pascoal A. , Nambiar M.
Published: August 2009

AbstractThe Idukki Reservoir at an altitude of 748 m covering an area of 53 km2 is surrounded by tropical forests in the Western Ghats in the southwestern Indian state of Kerala. We used the small autonomous underwater vehicle (AUV) Maya with onboard sensors
of dissolved oxygen, chlorophyll, turbidity, temperature, and depth to monitor the water quality environment of the Idukki Reservoir in May 2006. The use of AUVs in confined spaces like small lakes and reservoirs is new and uncommon, requiring extra safety to be implemented. As this is a prototype
AUV, we shall describe in brief key aspects of the vehicle attributes, namely, its novel mechanical design, the autopilots that control the heading and cruising depth, and the safety and endurance of the platform. The data acquired by Maya revealed an acute oxygen deficiency at 21 m,
a mid-water low turbidity layer between 10 m and 15 m, and a prominent chlorophyll maximum in the thermocline region of Idukki waters at 6 m. These experiments were repeated a year later in May 2007 and were in unambiguous agreement with the 2006 findings of hypoxia. These are the first observations
of hypoxic processes using a small AUV in any Indian lake. The relevance of these results in freshwater systems shows similarities to hypoxia in saline coastal waters of the west coast of India and is discussed briefly.
An Empirical Study on Port Choice Behaviors of Shippers in a Multiple-Port Region
Authors: Chou Chien-Chang
Published: August 2009

AbstractIn the international trade cargo logistics system, the port choice of the shipper is seen to depend not only on transportation costs, but also on the value of the cargoes being shipped. In many previous studies, researchers have assumed that the ultimate aim of shippers
when making port choices was to minimize inland freight costs. They then used that assumption to develop mathematical programming models for port choices. In practice, however, when making decisions about port choices, shippers always focus on total logistics costs. In other words, shippers
not only aim to minimize the inland freight costs but also consider the frequency of ship callings. Thus, in this paper, a mathematical programming model for port choice of shippers, which not only considers inland freight costs but also takes into account the frequency of ship callings, is
proposed and tested using a Taiwanese port case. The results show that the model proposed in this paper can be used to explain the actual port choice behaviors of Taiwanese shippers accurately.
Critical Care Clinicians’ Knowledge of Evidence-Based Guidelines for Preventing Ventilator-Associated Pneumonia
Authors: El-Khatib Mohamad F. , Zeineldine Salah , Ayoub Chakib , Husari Ahmad , Bou-Khalil Pierre K.
Published: August 2009

Background Ventilator-associated pneumonia is the most common hospital-acquired infection among patients receiving mechanical ventilation in an intensive care unit. Different initiatives for the prevention of ventilator-associated pneumonia have been developed and recommended.

Objective To evaluate knowledge of critical care providers (physicians, nurses, and respiratory therapists in the intensive care unit) about evidence-based guidelines for preventing ventilator-associated pneumonia.

Methods Ten physicians, 41 nurses, and 18 respiratory therapists working in the intensive care unit of a major tertiary care university hospital center completed an anonymous questionnaire on 9 nonpharmacological guidelines for prevention of ventilator-associated pneumonia.

Results The mean (SD) total scores of physicians, nurses, and respiratory therapists were 80.2% (11.4%), 78.1% (10.6%), and 80.5% (6%), respectively, with no significant differences between them. Furthermore, within each category of health care professionals, the scores of professionals with less than 5 years of intensive care experience did not differ significantly from the scores of professionals with more than 5 years of intensive care experience.

Conclusions A health care delivery model that includes physicians, nurses, and respiratory therapists in the intensive care unit can result in an adequate level of knowledge on evidence-based nonpharmacological guidelines for the prevention of ventilator-associated pneumonia.
Iced vs Room-Temperature Injectates for Cardiac Index Measurement During Hypothermia and Normothermia
Authors: Walsh Elissa , Adams Sheila , Chernipeski Janine , Cloud Jenny , Gillies Elizabeth , Fox Robert , Luckeroth Patti , Rice Marsha , Salamanca Cora , Sherman Betty , Nezworski Andrea , Ash Tracey
Published: August 2009

Background Few data are available on the accuracy of thermodilution measurements of cardiac index with room-temperature injectates and a closed delivery system in patients with low cardiac indexes and/or hypothermic body temperatures.

Objective To compare iced and room-temperature injectates for thermodilution measurement of cardiac index in postoperative cardiac surgical patients during hypothermia and normothermia.

Methods In a convenience sample of cardiac surgical patients in a cardiac recovery unit, cardiac index was measured with both room-temperature and iced injectates during hypothermia (≤36.0°C) and normothermia (≥36.1°C and ≤38.0°C). Device bias and precision were calculated and graphed by using the Bland-Altman method. A Student t test was used to determine differences between cardiac indexes by injectate temperature.

Results A total of 38 patients were studied. Mean bias and precision for room-temperature and iced injectates in all patients were 0.11 (SD, 0.27) during hypothermia and −0.03 (SD, 0.21) during normothermia. In hypothermic patients, cardiac index differed significantly between room-temperature and iced injectates (t1,37 = 2.41, P = .02). Cardiac index measurements did not differ between room-temperature and iced injectates in normothermic patients (P = .33).

Conclusions Although significant differences in thermodilution cardiac index were found between room-temperature and iced injectates during hypothermic body temperatures, these differences were small (mean, <0.11). These findings add to the results of the few studies on accuracy of room-temperature injectates for thermodilution measurement of cardiac index.
Age-Dependent B Cell Autoimmunity to a Myelin Surface Antigen in Pediatric Multiple Sclerosis
Authors: McLaughlin Katherine A. , Chitnis Tanuja , Newcombe Jia , Franz Bettina , Kennedy Julia , McArdel Shannon , Kuhle Jens , Kappos Ludwig , Rostasy Kevin , Pohl Daniela , Gagne Donald , Ness Jayne M. , Tenembaum Silvia , O'Connor Kevin C. , Viglietta Vissia , Wong Susan J. , Tavakoli Norma P. , de Seze Jerome , Idrissova Zhannat , Khoury Samia J. , Bar-Or Amit , Hafler David A. , Banwell Brenda , Wucherpfennig Kai W.
Published: August 2009

Multiple sclerosis (MS) typically manifests in early to mid adulthood, but there is increasing recognition of pediatric-onset MS, aided by improvements in imaging techniques. The immunological mechanisms of disease are largely unexplored in pediatric-onset MS, in part because studies have historically focused on adult-onset disease. We investigated autoantibodies to myelin surface Ags in a large cohort of pediatric MS cases by flow cytometric labeling of transfectants that expressed different myelin proteins. Although Abs to native myelin oligodendrocyte glycoprotein (MOG) were uncommon among adult-onset patients, a subset of pediatric patients had serum Abs that brightly labeled the MOG transfectant. Abs to two other myelin surface Ags were largely absent. Affinity purification of MOG Abs as well as competition of binding with soluble MOG documented their binding specificity. Such affinity purified Abs labeled myelin and glial cells in human CNS white matter as well as myelinated axons in gray matter. The prevalence of such autoantibodies was highest among patients with a very early onset of MS: 38.7% of patients less than 10 years of age at disease onset had MOG Abs, compared with 14.7% of patients in the 10- to 18-year age group. B cell autoimmunity to this myelin surface Ag is therefore most common in patients with a very early onset of MS.
Trends in fatalities due to poisoning at Umtata General Hospital, Mthatha (1993–2005)
Authors: Meel Banwari L.
Published: August 2009

Poisoning is a common method of committing suicide in this region of South Africa. Females generally ingest poisons but it is increasingly becoming common in males too. This is a record review of autopsies carried out at the Umtata (Mthatha) General Hospital mortuary, which forms part of the teaching hospital of the Walter Sisulu University Medical School. There were 10 230 unnatural deaths between 1993 and 2005. Of these deaths, 161 (1.6%) were deaths due to poisoning. There was a marked increase in death by poisoning from 2.5% in 1993 to 13.7% in 2004. The highest percentage (17.4%) of poison-related deaths was in 2001, and the lowest (2.5%) was in 1993 and 1994. About two-thirds of victims (66%) were males, and more than half of the victims (51.5%) were in the 11 to 30 age group. There is an increasing trend in fatalities due to poisoning at Umtata General Hospital, Mthatha.
N‐Terminal Sequence Analysis of Proteins and Peptides
Authors: Speicher Kaye D. , Gorman Nicole , Speicher David W.
Published: August 2009

Automated N‐terminal sequence analysis involves a series of chemical reactions that derivatize and remove one amino acid at a time from the N‐terminus of purified peptides or intact proteins. At least several picomoles of a purified protein or 10 to 20 pmol of a purified peptide with an unmodified N‐terminus is required to obtain useful sequence information. In recent years, the demand for N‐terminal sequencing has decreased substantially as some applications for protein identification and characterization can now be more effectively performed using mass spectrometry. However, N‐terminal sequencing remains the method of choice for verifying the N‐terminal boundary of recombinant proteins, determining the N‐terminus of protease‐resistant domains, identifying proteins isolated from species where most of the genome has not yet been sequenced, and mapping modified or crosslinked sites in proteins that prove to be refractory to analysis by mass spectrometry. Curr. Protoc. Protein Sci. 57:11.10.1‐11.10.31. © 2009 by John Wiley & Sons, Inc.
Overview of Glycoconjugate Analysis
Authors: Varki Ajit , Freeze Hudson H. , Manzi Adriana E.
Published: August 2009

Whereas DNA, RNA, and proteins are linear polymers that can usually be directly sequenced, glycans show substantially more complexity, having branching and anomeric configurations (α and β linkages). The biosynthesis of glycans, termed glycosylation, is extremely complex, is not template‐driven, varies among different cell types, and cannot be easily predicted from simple rules. This overview discusses the stereochemistry of monosaccharides and glycans and provides diagrammatic representations of monosaccharides (Fisher projections and Haworth representations) and formulas for representation of glycan chains. A glossary of terms used in glycobiology is also provided. Curr. Protoc. Protein Sci. 57:12.1.1‐12.1.10. © 2009 by John Wiley & Sons, Inc.
Metabolic Radiolabeling of Animal Cell Glycoconjugates
Authors: Diaz Sandra , Varki Ajit
Published: August 2009

Useful information about glycoconjugates can be obtained by labeling their aglycone (noncarbohydrate) portions—e.g., labeling proteins with radioactive amino acids—and then using techniques described elsewhere in this chapter to infer the presence, type, and nature of glycan chains. This unit describes metabolic labeling techniques that provide more specific information about the structure, sequence, and distribution of the sugar chains of glycoconjugates. Following metabolic labeling, the radioactive glycoconjugate of interest is isolated, individual glycosylation sites are identified and separated if necessary, and the labeled glycans are subjected to structural analysis. Curr. Protoc. Protein Sci. 57:12.2.1‐12.2.15. © 2009 by John Wiley & Sons, Inc.
Combinatorial Peptide Synthesis on a Microchip
Authors: Schirwitz Christopher , Block Ines , König Kai , Nesterov Alexander , Fernandez Simon , Felgenhauer Thomas , Leibe Klaus , Torralba Gloria , Hausmann Michael , Lindenstruth Volker , Stadler Volker , Breitling Frank , Bischoff F. Ralf
Published: August 2009

Microchips are used in the combinatorial synthesis of peptide arrays by means of amino acid microparticle deposition. The surface of custom‐built microchips can be equipped with an amino‐modified poly(ethylene glycol)methacrylate (PEGMA) graft polymer coating, which permits high loading of functional groups and resists nonspecific protein adsorption. Specific microparticles that are addressed to the polymer‐coated microchip surface in a well defined pattern release preactivated amino acids upon melting, and thus allow combinatorial synthesis of high‐complexity peptide arrays directly on the chip surface. Currently, arrays with densities of up to 40,000 peptide spots/cm2 can be generated in this way, with a minimum of coupling cycles required for full combinatorial synthesis. Without using any additional blocking agent, specific peptide recognition has been verified by background‐free immunostaining on the chip‐based array. This unit describes microchip surface modification, combinatorial peptide array synthesis on the chip, and a typical immunoassay employing the resulting high‐density peptide arrays. Curr. Protoc. Protein Sci. 57:18.2.1‐18.2.13. © 2009 by John Wiley & Sons, Inc.
Delay‐dependent robust L2–L∞ filtering of T‐S fuzzy systems with time‐varying delays
Authors: Li Ze , Xu Shengyuan , Zou Yun , Chu Yuming
Published: August 2009

This paper considers the problem of robust delay‐dependent L2–L∞ filtering for a class of Takagi–Sugeno fuzzy systems with time‐varying delays. The purpose is to design a fuzzy filter such that both the robust stability and a prescribed L2–L∞ performance level of the filtering error system are guaranteed. A delay‐dependent sufficient condition for the solvability of the problem is obtained and a linear matrix inequality (LMI) approach is developed. A desired filter can be constructed by solving a set of LMIs. Copyright © 2009 John Wiley & Sons, Ltd.
Electrospinning of Manmade and Biopolymer Nanofibers—Progress in Techniques, Materials, and Applications
Authors: Agarwal Seema , Greiner Andreas , Wendorff Joachin H.
Published: August 2009

Electrospinning of nanofibers has developed quickly from a laboratory curiosity to a highly versatile method for the preparation of a wide variety of nanofibers, which are of interest from a fundamental as well as a technical point of view. A wide variety of materials has been processed into individual nanofibers or nanofiber mats with very different morphologies. The diverse properties of these nanofibers, based on different physical, chemical, or biological behavior, mean they are of interest for different applications ranging from filtration, antibacterial coatings, drug release formulations, tissue engineering, living membranes, sensors, and so on. A particular advantage of electrospinning is that numerous non‐fiber forming materials can be immobilized by electrospinning in nanofiber nonwovens, even very sensitive biological objects such as virus, bacteria, and cells. The progress made during the last few years in the field of electrospinning is fascinating and is highlighted in this Feature Article, with particular emphasis on results obtained in the authors' research units. Specific areas of importance for the future of electrospinning, and which may open up novel applications, are also highlighted.
Synthesis and characterization of poly(dimethylsiloxane‐urethane) nanocomposites: Effect of (in)completely condensed silsesquioxanes on thermal, morphological, and mechanical properties
Authors: Madhavan K. , Gnanasekaran D. , Reddy B. S. R.
Published: August 2009

The structural properties of completely condensed and incompletely condensed silsesquioxane in the polyurethane nanocomposites containing 17.5 wt % of silsesquioxane was investigated by FTIR, TGA, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and DMA techniques. FTIR spectra shows the existence of hydrogen bonding in the PU‐POSS system. The intensity of hydrogen bonding decreases with the increase in POSS‐H loading suggesting the prevention of the formation of hydrogen bonding by the addition of POSS‐H molecule. SEM analysis reveals the incompatibility of POSS‐H molecule in the PU matrices exhibiting greater extent of phase separation and a large number of POSS aggregates on the addition of POSS‐H molecule in the PU‐POSS matrices. The TGA thermograms show that the POSS‐PU hybrids possess excellent thermal stabilities. However, the incorporation of POSS‐H molecule leads to a decrease in the thermal properties and only the char yield values increase with the increase in the POSS‐H content in the PU‐POSS hybrids. The XRD pattern reveals that the crystalline structure of POSS molecules are destroyed by the polymer matrices in the PU‐POSS hybrid films. The decrease in the bending storage modulus E′ values with the increase in the POSS‐H content proves the retardation of hydrogen bonding formation by the POSS‐H molecule in the PU‐POSS hybrid. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Microspheres of calcium carbonate composite regulated by sodium polyacrylates with various ways
Authors: Jiang Fuguang , Yang Yuhong , Huang Lei , Chen Xin , Shao Zhengzhong
Published: August 2009

Microspheres of calcium carbonate (CaCO3)/sodium polyacrylate (PAAs)/H2O composite were synthesized by adding PAAs to the supersaturated solution of CaCO3. It was found that the sizes of microsphere were influenced by the concentration and average molecular weight (Mw) of PAAs. Particularly, the polymorph of CaCO3in the microspheres could be regulated byMwof PAAs, that is, the formation of aragonite was induced by PAAs with lowerMw, while the amorphous calcium carbonate (ACC) was facilitated by PAAs with a higher one. Both polymorphs in produced microspheres were stable in air for longer than 3 months. In addition, it was revealed that the formation of calcite crystals was suppressed by a highly concentrated solution of PAAs. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermal‐shrinkage investigation of the chemical reaction during the stabilization of polyacrylonitrile fibers
Authors: Hou Yongping , Sun Tongqing , Wang Haojing , Wu Dong
Published: August 2009

It has been proposed that during the stabilization of polyacrylonitrile fibers, the reaction is initiated in the amorphous region and then propagates to the ordered region. However, the evidence is unsatisfactory, and some is quite controversial. It has been confirmed in this study through an examination of the shrinkage behavior and properties of stabilized polyacrylonitrile fibers that the cyclization reaction is initiated at 160°C in the amorphous region and that it propagates to the ordered region at about 200°C. Most of the nitriles can be transferred to a ladder polymer structure when the stabilization temperature is beyond 240°C, and the key temperature during stabilization is 240°C. For a higher degree of cyclization, the stabilization temperature should not be below 240°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Impact resistant polymeric glasses using compressive pre‐stress
Authors: Archer Jared S. , Lesser Alan J.
Published: August 2009

The application of an externally applied pre‐stress on impact properties is studied on polymethyl methacrylate (PMMA) organic glass. Samples are tested under equi‐biaxial compression, simple shear and a combination of biaxial compression and shear. Equi‐biaxial compression is shown to increase the threshold stress level for projectile penetration whereas shear pre‐stress has a large effect on the overall energy absorbed during an impact. There is also an apparent interaction observed between compression and shear to dramatically increase the threshold stress. Pre‐stressed laminates show an increase in damage area because of the unique formation of a secondary cone. Higher levels of compressive equi‐biaxial pre‐stress significantly increase the stress relaxation time because of the corresponding increase in hydrostatic stress. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009