bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Decision Networks Applications in Active Learning Simulators
Authors: Noguez Julieta , Muñoz Karla , Neri Luis , Robledo-Rella Víctor , Aguilar Gerardo
Published: November 2011

Active learning simulators (ALSs) allow students to practice and carry out experiments in a safe environment – anytime, anywhere. Well-designed simulations may enhance learning, and provide the bridge from concept to practical understanding. Nevertheless, learning with ALS depends largely on the student’s ability to explore and interpret the performed experiments. By adding an Intelligent Tutoring System (ITS), it is possible to provide individualized personal guidance to students. The challenges are how an ITS properly assesses the cognitive state of the student based on the results of experiments and the student’s interaction, and how it provides adaptive feedback to the student. In this chapter we describe how an ITS based on Dynamic Decision Networks (DDNs) is applied in an undergraduate Physics scenario where the aim is to adapt the learning experience to suit the learners’ needs. We propose employing Probabilistic Relational Models (PRMs) to facilitate the construction of the model. These are frameworks that enable the definition of Probabilistic Graphical and Entity Relationship Models, starting from a domain, and in this case, environments of ALSs. With this representation, the tutor can be easily adapted to different experiments, domains, and student levels, thereby minimizing the development effort for building and integrating Intelligent Tutoring Systems (ITS) for ALSs. A discussion of the methodology is addressed, and preliminary results are presented.
POMDP Models for Assistive Technology
Authors: Hoey Jesse , Poupart Pascal , Boutilier Craig , Mihailidis Alex
Published: November 2011

This chapter presents a general decision theoretic model of interactions between users and cognitive assistive technologies for various tasks of importance to the elderly population. The model is a partially observable Markov decision process (POMDP) whose goal is to work in conjunction with a user towards the completion of a given activity or task. This requires the model to monitor and assist the user, to maintain indicators of overall user health, and to adapt to changes. The key strengths of the POMDP model are that it is able to deal with uncertainty, it is easy to specify, it can be applied to different tasks with little modification, and it is able to learn and adapt to changing tasks and situations. This chapter describes the model, gives a general learning method which enables the model to be learned from partially labeled data, and shows how the model can be applied within our research program on technologies for wellness. In particular, we show how the model is used in four tasks: assisted handwashing, stroke rehabilitation, health and safety monitoring, and wheelchair mobility. The first two have been fully implemented and tested, and results are summarized. The second two are meant to demonstrate how the POMDP can be applied across a wide variety of domains, but do not have specific implementations or results. The chapter gives an overview of ongoing work into each of these areas, and discusses future directions.
Applications of Computational and Model-Based Statistical Methodologies in Archaeology
Authors: Papageorgiou Ioulia
Published: November 2011

Quantitative Archaeology had a rapid development in the past few decades due to the parallel development of methodologies in Physics, Chemistry and Geology that can be implemented in archaeological findings and produce measurements on a number of variables. Those measurements form the data, the basis for a statistical analysis, which in turn can provide us with objective results and answers, within the prediction or estimation framework, about the archaeological findings. Exploratory statistical analysis was almost exclusively used initially for analyzing such data mainly because of their simplicity. The simplicity originates from the fact that exploratory techniques do not rely on any distribution assumption and conduct a non-parametric statistical analysis. However the recent development of the statistical methodology and the computing software allows us to make use of more sophisticated statistical techniques and obtain more informative results. We explore and present applications of three such techniques. The finite mixture approach for model based clustering, the latent class model and the Bayesian mixture of normal distributions with unknown number of components. All three methods can be used for identifying sub-groups in the sample and classify the items.
Writer Identification in Old Handwritten Music Scores
Authors: Fornés Alicia , Lladós Josep , Sánchez Gemma , Bunke Horst
Published: November 2011

Writer identification in handwritten text documents is an active area of study, whereas the identification of the writer of graphical documents is still a challenge. The main objective of this work is the identification of the writer in old music scores, as an example of graphic documents. The writer identification framework proposed combines three different writer identification approaches. The first one is based on the use of two symbol recognition methods, robust in front of hand-drawn distortions. The second one generates music lines and extracts information about the slant, width of the writing, connected components, contours and fractals. The third approach generates music texture images and computes textural features. The high identification rates obtained demonstrate the suitability of the proposed ensemble architecture. To the best of our knowledge, this work is the first contribution on writer identification from images containing graphical languages.
Automatic Classification of Decorative Patterns in the Minoan Pottery of Kamares Style
Authors: Stanco Filippo , Tanasi Davide , Guarnera Giuseppe Claudio , Gallo Giovanni
Published: November 2011

An important feature of the Minoan culture is the pottery of Kamares style, that documents the Cretan cultural production between the first half of the 2nd millennium BC. This high level painted production, characterized by the combination of several diverse motifs, presents an enormous decorative repertoire. The extraordinary variety of combinations between elementary motifs according to a complex visual syntax makes interesting the automatic identification of the motifs, particularly upon potsherds. A complete pipeline to accomplish this task is still a challenge to Computer Vision and Pattern Recognition. Starting from a digital image ROI identification, motif extraction, robust contour detection should be performed to obtain a bag of digital shapes. In a second phase each of the extracted shapes has to be classified according to prototypes in a database produced by an expert. The co-occurrence of the different shapes in a specimen will, in turn, be used to help the archaeologists in the cultural and even chronological setting.
Opportunities and Challenges in Porting a Parallel Code from a Tightly-Coupled System to the Distributed EU Grid, Enabling Grids for E-sciencE
Authors: Costen Fumie , Balasko Akos
Published: November 2011

The computational architecture of Enabling Grids for E-sciencE is introduced as it made our code porting very challenging, and the discussion presented is directly applicable to EGEE users. The final solution to the code poring problem is proposed, and its performance is examined. The solution to this problem be generally faced in the other large scale computation and so is applicable to users of other HPC facilities. This chapter gives a hint to those who have difficulties in applications with heavy data Input/Output (I/O) under the computational environment whose weak point is the data I/O.
Stochastic Simulations in Systems Biology
Authors: Hafner Marc , Koeppl Heinz
Published: November 2011

With the advances in measurement technology for molecular biology, predictive mathematical models of cellular processes come in reach. A large fraction of such models addresses the kinetics of interaction between biomolecules such as proteins, transcription factors, genes, and messenger RNA. In contrast to classical chemical kinetics – utilizing the reaction-rate equation – the small volume of cellular compartments requires accounting for the stochasticity of chemical kinetics. In this chapter, we discuss methods to generate sample paths of this underlying stochastic process for situations where the well-stirredness or fast-diffusion assumption holds true. We introduce various approximations to exact simulation algorithms that are more efficient in terms of computational complexity. Moreover, we discuss algorithms that account for the multi-scale nature of cellular reaction events.
Visualization
Authors: Leng Joanna , Rhyne Theresa-Marie , Sharrock Wes
Published: November 2011

This chapter focuses on state of the art at the intersection of visualization and CSE. From understanding current trends it looks to future applications for these technologies. Some background is provided into visualization and its relation with CSE as well as with software and hardware frameworks that visualization systems depend on. Important emerging research areas are identified, including: interactive simulation and computational steering; collaborative, remote visualization and visualization services; VR technologies for visualization; user experience and assessment; teaching and serious gaming; communicating science to the public; ultra-scale visualization; and computational aesthetics. This should present the readers with real possibilities for CSE no matter what their disciplinary background.
Integrating Data Management and Collaborative Sharing with Computational Science Research Processes
Authors: Kleese van Dam Kerstin , James Mark , Walker Andrew M.
Published: November 2011

This chapter describes the key principles and components of a good data management system, provides real world examples of how these can be successfully integrated with scientific research processes and enable successful data sharing, provides an outlook on future developments, and discusses lessons learned. We conclude with a short section on how to get started for those whose interest has been piqued.
Building for the Future
Authors: Salleh Hafez , Lou Eric
Published: November 2011

This chapter provides the IT readiness assessment for before and after scenarios of IT systems implementation in a construction consultancy company providing multi-disciplinary services for the construction industry throughout the United Kingdom. The services offered include building surveying, quantity surveying, project management, civil and structural engineering design, and mechanical and electrical engineering design, among others. On application of the maturity model it was found that the overall processes for managing information are improving since the introduction of the new IT system. Prior to the project, the development of IT/IS was driven to perform daily work tasks that required the company to run a business. The new systems has streamlined the organization-wide communication, which the previous system did not have the capability to do, and to reduce cost for document reproduction. The level of IT skills prior to the project was relatively low; the introduction of the new system has helped the company to increase their staff’s IT skills.
An E-Support Firm’s Response to Local E-Readiness and the Global E-Business Environment
Authors: Effah John , Light Ben
Published: November 2011

The purpose of this study is to understand a small e-support firm’s response to the local e-readiness and the global e-business environment in a developing context. E-Support firms provide Web development and consultancy services to user organizations, assisting them in their uptake and maintenance of their Internet applications. Within the e-readiness research area, little is known about e-support firms, particularly in connection with their interaction with their local and the global e-business environment. As yet the emphasis on e-readiness studies has been at the national level. Nevertheless, the e-support sector is very significant in the successful adoption and diffusion of the Internet and related applications in any economy. It is thus important to understand how such firms relate to their e-business environments. That said, this study draws on the interpretive case study of a small e-support firm in Ghana, a developing context, to investigate the firm’s response to the e-readiness level of the local and the global e-business environment. Findings show that the firm could employ resources from the global environment to address most of the infrastructural challenges posed by a relatively poor local e-readiness context. However, its attempt to transfer advanced e-business technologies from the global e-business environment to the local e-business context did not succeed. This chapter offers implications for practice and research concerning the notion of reconciling local and global e-business environments in the small e-support sector.
Technology and Social-Emotional Development in the Early Childhood Environments
Authors: Brown Judy , Winsor Denise L. , Blake Sally
Published: November 2011

The research about the importance of social and emotional roles in learning has increased the focus in many early childhood programs on the social-emotional domains of development. The perceptions of the effects computers and other technology tools have on social/emotional development of young children may influence the acceptance and use of technology in these classrooms. This chapter discusses the research related to technology and social-emotional development, parents’ perceptions of what social interactions are important in relation to child-to-child and child-to adult realm, theoretical influences on educational environments, and approaches to intentional use of tools to support these important domains. Technology has changed the socio-cultural environment globally and we, as educators of young children, need to change how we approach social and emotional support for our children.
A Parent’s Guide to Support Technologies for Preschool Students with Disabilities
Authors: Casey Laura Baylot , Williamson Robert L.
Published: November 2011

Parents encounter many challenges when facing the need to raise and support a child with a disability. Many find technology to be of assistance, first turning to the Internet as a source of information and later turning to assistive technologies to directly support the needs of their child. This chapter outlines the multiple uses of technology related to the raising and support of young children with disabilities. The information provided serves to give an overview perspective while simultaneously providing actual specifics related to technology that can be useful to parents throughout the journey of raising a child with special needs.
Approximate Matching Between XML Documents and Schemas with Applications in XML Classification and Clustering
Authors: Xing Guangming
Published: November 2011

Classification/clustering of XML documents based on their structural information is important for many tasks related with document management. In this chapter, we present a suite of algorithms to compute the cost for approximate matching between XML documents and schemas. A framework for classifying/clustering XML documents by structure is then presented based on the computation of distances between XML documents and schemas. The backbone of the framework is the feature representation using a vector of the distances. Experimental studies were conducted on various XML data sets, suggesting the efficiency and effectiveness of our approach as a solution for structural classification/clustering of XML documents.
XML Document Clustering
Authors: Antonellis Panagiotis
Published: November 2011

The wide use of XML as the de facto standard of storing and exchanging information through Internet has led a wide spectrum of heterogeneous applications to adopt XML as their information representation model. The heterogeneity of XML data sources has brought up the problem of efficiently clustering a set of XML documents. However, traditional clustering algorithms cannot be applied due to the semistructured nature of XML, which contains both structure and content features. Hence, special techniques should be used that would take into account the XML semantics in order to address the problem of XML clustering. The described approaches, based on either the structure or the content or both, manage to successfully address the problem and can be applied efficiently in real-world applications.
Fuzzy Approaches to Clustering XML Structures
Authors: Kozielski Michal
Published: November 2011

Information on the hierarchical nature of XML data is essential in tasks of learning from XML document structures. Within this view, XML documents can be regarded as multi-represented data, which is the case when multiple representations of the document correspond to the generation of features at each structure level of the document separately. This chapter raises the importance of using fuzzy approaches to clustering XML document structures, since these approaches are shown to be effective in combining the information coming from different document representations that correspond to different hierarchy levels. For this purpose, we overview fuzzy encoding and similarity methods and present fuzzy clustering approaches which are particularly suited for being extended to handle XML document structures. We propose two different scenarios of fuzzy clustering of XML structures, which aim to either encode the document structure hierarchy using a fuzzy bag model or to specifically handle the multi-representation of the documents.
XML Tree Classification on Evolving Data Streams
Authors: Bifet Albert , Gavaldà Ricard
Published: November 2011

Nowadays, advanced analysis of data streams is quickly becoming a key area of data mining research, as the number of applications demanding such processing increases. Online mining when such data streams evolve over time, that is, when concepts drift or change completely, is becoming one of the core issues. At the same time, closure-based mining on relational data has recently provided some interesting algorithmic developments as well as practical uses. In this chapter we show how to use closure-based mining to reduce drastically the number of attributes in XML tree classification tasks. Moreover, using maximal frequent trees, we reduce even more the number of attributes needed in tree classification, in many cases without losing accuracy. We show a general framework to classify XML trees using subtree occurrence, composing a Tree XML Closed Frequent Miner with a classifier algorithm. We present specific methods that can adaptively mining closed patterns from data streams that change over time.
Data Driven Encoding of Structures and Link Predictions in Large XML Document Collections
Authors: Hagenbuchner Markus , Tsoi Chung , Zhang Shu Jia , Kc Milly
Published: November 2011

In recent years there have been some significant research towards the ability of processing related data, particularly the relatedness among atomic elements in a structure with those in another structure. A number of approaches have been developed with various degrees of success. This chapter provides an overview of machine learning approaches for the encoding of related atomic elements in one structure with those in other structures. The chapter briefly reviews a number of unsupervised approaches for such data structures which can be used for solving generic classification, regression, and clustering problems. We will apply this approach to a particularly interesting and challenging problem: The prediction of both the number and their locations of the in-links and out-links of a set of XML documents. In this problem, we are given a set of XML pages, which may represent web pages on the Internet, with in-links and out-links. Based on this training dataset, we wish to predict the number and locations of in-links and out-links of a set of XML documents, which are as yet not linked to other existing XML documents. To the best of our knowledge, this is the only known data driven unsupervised machine learning approach for the prediction of in-links and out-links of XML documents.
Discovering Higher Level Correlations from XML Data
Authors: Cagliero Luca , Cerquitelli Tania , Garza Paolo
Published: November 2011

This chapter proposes the XML-GERMI framework to support XML data analysis by automatically extracting generalized association rules (i.e., higher level correlations) from XML data. The proposed approach, which extends the concept of multiple-level association rules, is focused on extracting generalized rules from XML data. To drive the generalization phase of the extraction process, a taxonomy is exploited to aggregate features at different granularity levels. Experiments performed on both real and synthetic datasets show the adaptability and the effectiveness of the proposed framework in discovering higher level correlations from XML data.
Organizing XML Documents on a Peer–to–Peer Network by Collaborative Clustering
Authors: Gullo Francesco , Ponti Giovanni , Greco Sergio
Published: November 2011

In this chapter we address the problem of clustering XML documents in a collaborative distributed environment. We developed a clustering framework for XML sources distributed on a P2P network. XML documents are modeled based on a transactional representation which uses both XML structure and content information. The clustering method employs a centroid-based partitional scheme suitably adapted to work on a P2P network. Each peer is enabled to compute a clustering solution over its local repository and to exchange the resulting cluster representatives with the other peers. The exchanged cluster representatives are hence used to compute the global clustering solution in a collaborative way. Effectiveness and efficiency of the framework were evaluated on real XML document collections varying the number of peers. Experimental results have shown significant improvements of our collaborative distributed algorithm with respect to the centralized clustering setting in terms of execution time, achieving clustering solutions that still remain accurate with a moderately low number of nodes in the network.
A Research Model for Open Innovation
Authors: Rahman Hakikur , Ramos Isabel
Published: November 2011

With the advent of innovative technologies and long the setting of entrepreneurship development philosophy, context and business handling have been transformed from being traditional to innovative. Depending on diversity and nature of the transformation, innovation has been shifted from closed peripheries to open dimension. Looking at the immense benefits, ranging from small entrepreneurs to corporate to multinational, business houses are adopting various innovation techniques. However, the road to innovation, despite being a paradigm shift is not smooth and ready for many, particularly the small and medium enterprises (SMEs) who mainly deal with the clients at the outer peripheries of the social circle. Moreover, there is a research gap within the context of SME development through open innovation strategies. This chapter intends to initiate a research model for carrying out research on the development of SMEs through utilization of open innovation strategies. Along these contexts it has tried to synthesize aspects of opportunities and challenges surrounding SMEs development utilizing open and collaborative approaches. To set the research model, the paper has developed an innovation opportunity framework, both at the policy level and at the entrepreneur level. To validate the research hypothesis, the chapter hints at carrying out a three phase survey comprising selected SMEs.
Theoretical Model for a Local Economy Open Innovation Program
Authors: Porath Amiram
Published: November 2011

This chapter presents a model of open innovation as a collaborative effort of firms, mostly SMEs that are managed under a government support with the assistive involvement of academia. While normally industry-academia cooperation is R&D focused, the model presented is a model of open innovation not involving dedicated R&D. It deals with the process of assimilating existing technologies and methodologies; the model focuses on search, identification, and implementation phases to improve competitiveness through open innovation strategies. The model claims that specifically for SMEs, innovation not related to R&D, and especially open innovation, is hard to deal with alone. Therefore the model presents a group of SMEs working together towards that end, and the role of the governing authority supporting them. The model is supported by a short case study of a national program of Israel, the Users Association for Advanced Technologies.
Breast Cancer Treatment Practices in Elderly Women in a Community Hospital
Authors: Wang Hua , Singh Awinder P. , Luce Serena A. St. , Go Alan R.
Published: November 2011

Background. Elderly women with breast cancer are considered underdiagnosed and undertreated, and this adversely affects their overall survival.Methods. A total of 393 female breast cancer patients aged 70 years and older, diagnosed within the years 1989–1999, were identified from the tumor registry of The Brooklyn Hospital Center. Comparisons between the 3 different subgroups 70–74, 75–79, and 80 years and older were made using the Pearson Chi Square test.Results. Lumpectomy was performed in 42% of all patients, while mastectomy was done in 46% of patients. Adjuvant therapy such as chemotherapy, radiation therapy, and hormonal therapy were done in 12%, 25%, and 38%, respectively. Forty-seven percent of patients with positive lymph nodes received chemotherapy. Eighty-six percent of patients who were estrogen receptor-positive received adjuvant hormonal therapy. Overall five-year survival was only 14% for the ≥80 age group, compared to that of 32% and 35% for the 70–74 and the 75–79 age groups, respectively.Conclusions. Surgery was performed in majority of these patients, about half received lumpectomy, the other half mastectomy. Adjuvant therapies were frequently excluded, with only hormonal therapy being the most commonly used. Overall five-year survival is significantly worse in patients ≥80 years with breast cancer.
Anatomical Correlates of Age-Related Working Memory Declines
Authors: Schulze Evan T. , Geary Elizabeth K. , Susmaras Teresa M. , Paliga James T. , Maki Pauline M. , Little Deborah M.
Published: November 2011

Aging studies consistently show a relationship between decreased gray matter volume and decreased performance on working memory tasks. Few aging studies have investigated white matter changes in relation to functional brain changes during working memory tasks. Twenty-five younger and 25 older adults underwent anatomical magnetic resonance imaging (MRI) scans to measure gray matter volume, diffusion tensor imaging (DTI) to measure fractional anisotropy (FA) as a measure of white matter integrity, and functional magnetic resonance imaging (fMRI) while performing a working memory task. Significant increases in activation (fMRI) were seen in the left dorsal and ventral lateral prefrontal cortex with increased working memory load and with increased age (older showing greater bilateral activation). Partial correlational analyses revealed that even after controlling for age, frontal FA correlated significantly with fMRI activation during performance on the working memory task. These findings highlight the importance of white matter integrity in working memory performance associated with normal aging.
Identifying Factors Associated with Regular Physical Activity in Leisure Time among Canadian Adolescents
Authors: Godin Gaston , Anderson Donna , Lambert Léo-Daniel , Desharnais Raymond
Published: November 2011

Purpose.

The purpose of this study was to identify the factors explaining regular physical activity among Canadian adolescents.

Design.

A cohort study conducted over a period of 2 years.

Setting.

A French-language high school located near Québec City.

Subjects.

A cohort of 740 students (352 girls; 388 boys) aged 13.3 ± 1.0 years at baseline.

Measures.

Psychosocial, life context, profile, and sociodemographic variables were assessed at baseline and 1 and 2 years after baseline. Exercising almost every day during leisure time at each measurement time was the dependent variable.

Results.

The Generalized Estimating Equations (GEE) analysis indicated that exercising almost every day was significantly associated with a high intention to exercise (odds ratio [OR]: 8.33, confidence interval [CI]95%: 5.26, 13.18), being satisfied with the activity practiced (OR: 2.07, CI95%: 1.27, 3.38), perceived descriptive norm (OR: 1.82, CI95%: 1.41, 2.35), being a boy (OR:1.83, CI95%: 1.37, 2.46), practicing “competitive” activities (OR: 1.80, CI95%: 1.37, 2.36), eating a healthy breakfast (OR: 1.68, CI95%: 1.09, 2.60), and normative beliefs (OR: 1.48, CI95%: 1.14, 1.90). Specific GEE analysis for gender indicated slight but significant differences.

Conclusions.

This study provides evidence for the need to design interventions that are gender specific and that focus on increasing intention to exercise regularly.
Evaluating a Yogic Breathing and Meditation Intervention for Individuals Living with HIV/AIDS
Authors: Brazier Alison , Mulkins Andrea , Verhoef Marja
Published: November 2011

Purpose.

To assess the effectiveness of a group program aimed at improving well-being among individuals living with HIV/AIDS.

Methods.

A randomized controlled trial was used to evaluate a residential program designed to teach breathing, movement, and meditation techniques. Sixty-two participants were recruited from community HIV/AIDS organizations. Fifteen withdrawals from the study left 47 study participants. Standardized measures used were the Mental Health Index (MHI), the MOS-HIV Health Survey (MOS), and the Daily Stress Inventory (DSI), along with qualitative interviews.

Results.

A repeated-measures analysis of variance indicated positive changes in well-being on the MHI and the MOS, where the effect was primarily seen immediately following the program and disappeared at later data points. The DSI indicated an increase in experience and impact of stress over time for the intervention group postprogram. Alternatively, the qualitative interviews described positive changes in how participants were living their day-to-day lives.

Conclusion.

In order to capture the outcomes of this program properly, both qualitative and quantitative measures are needed.
Promoting Stair Use by Modeling: An Experimental Application of the Behavioral Ecological Model
Authors: Adams Marc A. , Hovell Melbourne F. , Irvin Veronica , Sallis James F. , Coleman Karen J. , Liles Sandy
Published: November 2011

Purpose.

This study evaluated the effect of behavioral modeling and social factors promoting stair use.

Design.

Alternating baseline and intervention phase experimental design.

Setting.

San Diego International Airport, San Diego, California.

Subjects.

Stair use was coded for 15,574 filmed participants.

Intervention.

This study compared the effects of three types of behavioral modeling: natural models (i.e., passersby), single experimental model (i.e., confederate), and confederate model pairs providing verbal prompts.

Measures.

Variables were coded based on systematic observation of videotapes, including demographics, day and time, and the following indicators of physical and social reinforcement contingencies: dress, luggage, children, social group, and speed. Reliability ranged from .64 to .88.

Analysis.

Bivariate and logistic regression models stratified by gender.

Results.

Stair use increased over baseline by 102.6% with no model present and by 61.8% in the presence of natural models for men and women (p < .001). Controlling for multiple covariates, the odds ratios for stair use ranged from 1.76 to 2.93 for men and from 1.82 to 2.54 for women across the levels with natural and confederate models present (all p < .001).

Conclusion.

Modeling can prompt stair use, and findings for social and environmental reinforcement contingencies support the Behavioral Ecological Model. Modeling may explain partial maintenance of stair use in public areas after removal of prompts (e.g., signs, banners). Results inform interventions for increasing physical activity as part of daily routines.
A Perceived Benefits and Barriers Scale for Strenuous Physical Activity in College Students
Authors: Brown Seth A. , Huber Daniel , Bergman Amber
Published: November 2011

Purpose.

Due to relatively low physical activity among college students, a standardized, reliable, and valid scale of perceived benefits and barriers for this population is critical. The purpose of this study was to develop a new scale, the Physical Activity Benefits and Barriers Scale, and determine whether the scale was appropriate for college students.

Methods.

An exploratory factor analysis of 26 benefit and 24 barrier items of physical activity was administered to 493 college students, followed by an examination of the relationship between the newly derived factors and physical activity, as well as test-retest reliability.

Results.

Twenty-eight items loaded on 10 factors that accounted for 60% of the variance, and 9 of the 10 factors were moderately associated with strenuous physical activity.

Discussion.

Psychometric properties were acceptable on this new scale, with the low motivation factor accounting for the highest amount of the variance in strenuous physical activity.
Work-to-Family Spillover and Fruit and Vegetable Consumption among Construction Laborers
Authors: Devine Carol M. , Stoddard Anne M. , Barbeau Elizabeth M. , Naishadham Deepa , Sorensen Glorian
Published: November 2011

Purpose.

Spillover is the effect of one role on another as working adults attempt to integrate demands from work and family. We conducted a survey to understand how worker, job, and family characteristics were related to negative work-to-family spillover and how spillover was related to fruit and vegetable consumption to inform intervention design.

Design.

A combined mail and telephone survey.

Setting.

A national random sample in the United States.

Subjects.

1108 (44% response) unionized construction laborers.

Measures.

Personal characteristics, job factors, family factors, work-to-family spillover, and fruit and vegetable consumption.

Analysis.

Multivariable logistic and least-squares regression.

Results.

A range of 20% to 50% of respondents reported negative work-to-family spillover, agreeing that work demands, time, fatigue, and stress interfered with family meals or food choices. Higher spillover was associated with job factors, being of white race/ethnicity, and having children at home. Lower fruit and vegetable consumption was associated with higher work-to-family spillover (p = .002), being of white race or ethnicity (p < .0001), and working the graveyard or day shift (p = .02).

Conclusion.

Negative experience of work-to-family spillover may link employment to fruit and vegetable consumption and thus to worker health. Understanding the contribution of spillover to fruit and vegetable consumption aids understanding of how work experience affects health.
Composition of wax esters is linked to diapause behavior of Calanus finmarchicus in a sea loch environment
Authors: Clark K. A. J. , Brierley A. S. , Pond D. W.
Published: November 2011

We studied the seasonal lipid dynamics of Calanus finmarchicus from Loch Etive, a semi‐enclosed fjordic environment on the west coast of Scotland, in relation to the diapause behavior of this species. Levels of total lipid and triacylglycerol in individual copepodid stage V (CVs) exhibited clear seasonal trends, with highest levels in June and progressively decreasing through late summer to winter. Wax esters in CVs were more variable, but followed a similar pattern. An index of the level of unsaturation of wax esters, effectively an indicator of the levels of polyunsaturated fatty acids in the wax ester reserves, were highest in midsummer and declined progressively through autumn and winter. Fatty acid analysis of total lipid in the CVs confirmed that the amounts of polyunsaturated fatty acids in the wax esters decreased, while amounts of saturated and monounsaturated fatty acids remained comparatively stable. Polyunsaturated wax esters are selectively catabolized by C. finmarchicus during diapause. Previous studies have linked unsaturation of wax esters in calanoid copepods to the initiation of diapause and buoyancy control, and we hypothesize that selective catabolism of polyunsaturated wax esters is linked to the processes of diapause termination and ascent to surface waters.
Mass-spectrometric identification of primary biological particle markers and application to pristine submicron aerosol measurements in Amazonia
Authors: Schneider J. , Freutel F. , Zorn S. R. , Chen Q. , Farmer D. K. , Jimenez J. L. , Martin S. T. , Artaxo P. , Wiedensohler A. , Borrmann S.
Published: November 2011

Abstract. The detection of primary biological material in submicron aerosol by means of thermal desorption/electron impact ionization aerosol mass spectrometry was investigated. Mass spectra of amino acids, carbohydrates, small peptides, and proteins, all of which are key building blocks of biological particles, were recorded in laboratory experiments. Several characteristic marker fragments were identified. The intensity of the marker signals relative to the total organic mass spectrum allows for an estimation of the content of primary biological material in ambient organic aerosol. The developed method was applied to mass spectra recorded during AMAZE-08, a field campaign conducted in the pristine rainforest of the central Amazon Basin, Brazil, during the wet season of February and March 2008. The low abundance of identified marker fragments places upper limits of 7.5% for amino acids and 5.6% for carbohydrates on the contribution of primary biological aerosol particles (PBAP) to the submicron organic aerosol mass concentration during this time period. Upper limits for the absolute submicron concentrations for both compound classes range from 0.01 to 0.1 μg m−3. Carbohydrates and proteins (composed of amino acids) make up for about two thirds of the dry mass of a biological cell. Thus, our findings suggest an upper limit for the PBAP mass fraction of about 20% to the submicron organic aerosol measured in Amazonia during AMAZE-08.
Changes in monoterpene mixing ratios during summer storms in rural New Hampshire (USA)
Authors: Haase K. B. , Jordan C. , Mentis E. , Cottrell L. , Mayne H. R. , Talbot R. , Sive B. C.
Published: November 2011

Abstract. Monoterpenes are an important class of biogenic hydrocarbons that influence ambient air quality and are a principle source of secondary organic aerosol (SOA). Emitted from vegetation, monoterpenes are a product of photosynthesis and act as a response to a variety of environmental factors. Most parameterizations of monoterpene emissions are based on clear weather models that do not take into account episodic conditions that can drastically change production and release rates into the atmosphere. Here, the monoterpene dataset from the rural Thompson Farm measurement site in Durham, New Hampshire is examined in the context of a set of known severe storm events. While some storm systems had a negligible influence on ambient monoterpene mixing ratios, the average storm event increased mixing ratios by 0.59 ± 0.21 ppbv, a factor of 93% above pre-storm levels. In some events, mixing ratios reached the 10's of ppbv range and persisted overnight. These mixing ratios correspond to increases in the monoterpene emission rate, ranging from 120 to 1240 g km−2 h−1 compared to an estimated clear weather rate of 116 to 193 g km−2 h−1. Considering the regularity of storm events over most forested areas, this could be an important factor to consider when modeling global monoterpene emissions and their resulting influence on the formation of organic aerosols.
Renewed methane increase for five years (2007–2011) observed by solar FTIR spectrometry
Authors: Sussmann R. , Forster F. , Rettinger M. , Bousquet P.
Published: November 2011

Abstract. Trends of column-averaged methane for the time period [1996, September 2011] are derived from the mid-infrared (mid-IR) solar FTIR time series at the Zugspitze (47.42° N, 10.98° E, 2964 m a.s.l.) and Garmisch (47.48° N, 11.06° E, 743 m a.s.l.). Trend analysis comprises a fit to the de-seasonalized time series along with bootstrap resampling for quantifying trend uncertainties. We find a positive trend during [1996, 1998] (9.0 [3.2, 14.7] ppb yr−1, Zugspitze, 95 % confidence interval), a non-significant growth during [1999, mid 2006] (0.8 [−0.1, 1.7] ppb yr−1, Zugspitze), and a significant renewed increase during [mid 2006, September 2011] of 5.1 [4.2, 6.0] ppb yr−1 for Garmisch, which is in agreement with 4.8 [3.8, 5.9] ppb yr−1 for Zugspitze. The agreement of methane trends at the two closely neighboring FTIR sites with strongly differing levels of integrated water vapor (min/max = 0.2 mm/12.7 mm for Zugspitze, 1.9 mm/34.9 mm for Garmisch) proves that potentially significant water-vapor-methane interference errors do not affect the trend results, if the updated mid-IR retrieval strategy MIR-GBM v1.0 is used. Furthermore, agreement of the trend of 6.6 ppb yr−1 derived from SCIAMACHY (WFMD v2.0) data for the time period [mid 2006, mid 2009] is found within the 95 % confidence interval of the ground-based FTIR result. While earlier studies using surface network data revealed changes of 8.0±0.6 ppb in 2007 and 6.4±0.6 ppb in 2008 (update from Dlugokencky et al., 2009), our updated result proves that meanwhile, the renewed methane increase has been persisting for >5 yr [mid 2006, September 2011]. This is either the longest and largest positive trend anomaly since >25 yr when systematic observations began or the onset of a new period of strongly increasing CH4 levels in the atmosphere. The 2007–2008 part of the anomaly was previously attributed to increased natural wetland emissions. For the full period from 2007 to 2011, our analysis of ECMWF ERA-INTERIM precipitations and 2-m temperatures shows that precipitations above tropical wetland areas increased in 2007–2008, decreased in 2009, and have been increasing again since 2010, while tropical land temperatures increased only slightly. As recent estimates of anthropogenic emissions are not yet available, it is not possible to finally conclude that the 2009–2011 period of methane increase was dominated by natural wetland emissions, although they probably play a significant role.
Seasonal variations of stable carbon isotopic ratios and biogenic tracer compounds of water-soluble organic aerosols in a deciduous forest
Authors: Miyazaki Y. , Fu P. , Kawamura K. , Mizoguchi Y. , Yamanoi K.
Published: November 2011

Abstract. To investigate the seasonal changes in biogenic water-soluble organic carbon (WSOC) aerosols in a boreal forest, aerosol samples were collected continuously in the canopy of a~deciduous forest in Northern Japan during 2009–2010. Stable carbon isotopic ratios of WSOC (δ13CWSOC) in aerosols exhibited a distinct seasonal cycle, with lower values from June through September (−25.5 ± 0.5‰). This cycle follows the net CO2 exchange between the forest ecosystem and the atmosphere, indicating that δ13CWSOC likely reflects the biological activity at the forest site. WSOC concentrations showed the highest values in early summer and autumn. Positive matrix factorization (PMF) analysis indicated that the factor in which biogenic secondary organic aerosols (BSOAs) dominated accounted for ~ 40% of the highest concentrations of WSOC, where BSOAs mostly consisted of α-/β-pinene SOA. In addition, primary biological aerosol particles (PBAPs) made similar contributions (~ 57%) to the WSOC near the canopy floor in early summer. This finding indicates that the production of both primary and secondary WSOC aerosols is important during the growing season in a deciduous forest. The methanesulfonic acid (MSA) maximum was also found in early summer and had a distinct vertical gradient with larger concentrations near the canopy floor. Together with the similar vertical gradients found for WSOC and δ13CWSOCas well as the α-/β-pinene SOA tracers, our results indicate that the forest floor, including ground vegetation and soil, acts as a significant source of the WSOC within a~forest canopy at the study site.
Factors influencing the stable carbon isotopic composition of suspended and sinking organic matter in the coastal Antarctic sea ice environment
Authors: Henley S. F. , Annett A. L. , Ganeshram R. S. , Carson D. S. , Weston K. , Crosta X. , Tait A. , Dougans J. , Fallick A. E. , Clarke A.
Published: November 2011

Abstract. A high resolution time-series analysis of stable carbon isotopic signatures in particulate organic carbon (δ13CPOC) and associated biogeochemical parameters in sea ice and surface waters provides an insight into the factors affecting δ13CPOC in the coastal western Antarctic Peninsula (WAP) sea ice environment. The study covers two austral summer seasons in Ryder Bay, northern Marguerite Bay between 2004 and 2006. A shift in diatom species composition during the 2005/2006 summer bloom to near-complete biomass dominance of Proboscia inermis is strongly correlated with a large ~10‰ negative isotopic shift in δ13CPOC that cannot be explained by a concurrent change in concentration or isotopic signature of CO2. We hypothesise that the δ13CPOC shift may be driven by the contrasting biochemical mechanisms and utilisation of carbon-concentrating mechanisms in different diatom species. These short-lived yet pronounced negative δ13CPOC excursions drive a 4‰ decrease in the seasonal average δ13CPOC signal, which is transferred to sediment traps and core-top sediments and consequently has the potential for preservation in the sedimentary record. This 4‰ difference between seasons of contrasting sea ice conditions and upper water column stratification matches the full amplitude of glacial-interglacial Southern Ocean δ13CPOC variability and, as such, we invoke phytoplankton species changes as a potentially important factor influencing sedimentary δ13CPOC. We also find significantly higher δ13CPOC in sea ice than surface waters, consistent with autotrophic carbon fixation in a semi-closed environment and possible contributions from post-production degradation, biological utilisation of HCO3- and production of exopolymeric substances (EPS). This study demonstrates the importance of surface water diatom speciation effects and isotopically heavy sea ice-derived material for δ13CPOC in Antarctic coastal environments and underlying sediments, with consequences for the utility of diatom-based δ13CPOC in the sedimentary record.