bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dose Optimization for Computed Tomography Localizer Radiographs for Low-Dose Lung Computed Tomography Examinations
Authors: Schmidt Bernhard T. , Hupfer Martin , Saltybaeva Natalia , Kolditz Daniel , Kalender Willi A. 
Published: August 2016

Introduction
Recent studies have shown a substantial reduction of radiation dose from computed tomography (CT) scans down to 0.1 mSv for lung cancer screening and cardiac examinations, when applying optimization techniques. Hence, CT localizer radiographs (LRs) might now be considered a significant contributor to the total dose of the CT examination. We investigated in our study the potential for reducing dose of the LRs by adapting the patient-specific acquisition parameters of the LR.

Materials and Methods
Localizer radiographs covering the lungs were acquired on 2 clinical scanners (64 slices, conventional detector [CD]; 96 slices, fully integrated detector [ID]) for 3 semianthropomorphic phantoms, representing a slim, a normal, and an obese adult. Starting at 120-kV tube voltage and 250-mA current were reduced until the image quality of the LR, and thereby the accuracy of the automatic exposure control was compromised; this was defined as a deviation of measured attenuation values in the center of the LR of more than 5% from the reference values measured at the highest tube voltage and current. Subsequent Monte Carlo calculations on anthropomorphic phantoms were performed to calculate organ and effective dose values for the respective optimal settings. In addition, effective dose values normalized to CTDIvol for tube voltages ranging from 60 to 160 kV were determined for the different combinations of phantom sizes, sexes, and LR views to evaluate dose efficiency.

Results
For the CD scanner, the optimal LR settings depended strongly on phantom size. Higher tube voltage and current were necessary for the larger phantoms. The ID scanner showed uncompromised LR quality for all phantoms using the lowest possible tube voltage-tube current combination of 80 kV and 20 mA. Depending on patient size and LR direction, effective dose values for the optimal settings ranged from 6 to 53 μSv and 3 to 11 μSv for the CD and ID scanner, respectively. For the example of an anterior-posterior LR on a normal patient, using the optimal settings instead of the standard settings on the ID scanner reduced LR dose from 53 μSv (120 kV, 30 mA) to 10 μSv (80 kV, 20 mA). The simulations for the different tube voltages show that effective dose and CTDIvol behave similarly for different views and patient sizes. However, the tube voltage level itself impacts the relationship between CTDIvol and effective dose, by up to a factor of 2.

Discussion
Dose from LRs may contribute significantly to the total effective dose of low-dose CT examinations such as lung cancer screening. Optimal LR settings can reduce LR dose substantially, but adaptations have to consider scanner characteristics, detector technology, and patient size. Thus, for low-dose CT examinations, such as cardiac examinations and lung cancer screening, LR optimization may result in a significant dose reduction and thereby in a substantial reduction of total dose.
The Use of Acoustic Radiation Force Decorrelation-Weighted Pulse Inversion for Enhanced Ultrasound Contrast Imaging
Authors: Herbst Elizabeth B. , Unnikrishnan Sunil , Wang Shiying , Klibanov Alexander L. , Hossack John A. , Mauldin Frank William 
Published: August 2016

Objectives
The use of ultrasound imaging for cancer diagnosis and screening can be enhanced with the use of molecularly targeted microbubbles. Nonlinear imaging strategies such as pulse inversion (PI) and “contrast pulse sequences” (CPS) can be used to differentiate microbubble signal, but often fail to suppress highly echogenic tissue interfaces. This failure results in false-positive detection and potential misdiagnosis. In this study, a novel acoustic radiation force (ARF)–based approach was developed for superior microbubble signal detection. The feasibility of this technique, termed ARF decorrelation-weighted PI (ADW-PI), was demonstrated in vivo using a subcutaneous mouse tumor model.

Materials and Methods
Tumors were implanted in the hindlimb of C57BL/6 mice by subcutaneous injection of MC38 cells. Lipid-shelled microbubbles were conjugated to anti-VEGFR2 antibody and administered via bolus injection. An image sequence using ARF pulses to generate microbubble motion was combined with PI imaging on a Verasonics Vantage programmable scanner. ADW-PI images were generated by combining PI images with interframe signal decorrelation data. For comparison, CPS images of the same mouse tumor were acquired using a Siemens Sequoia clinical scanner.

Results
Microbubble-bound regions in the tumor interior exhibited significantly higher signal decorrelation than static tissue (n = 9, P < 0.001). The application of ARF significantly increased microbubble signal decorrelation (n = 9, P < 0.01). Using these decorrelation measurements, ADW-PI imaging demonstrated significantly improved microbubble contrast-to-tissue ratio when compared with corresponding CPS or PI images (n = 9, P < 0.001). Contrast-to-tissue ratio improved with ADW-PI by approximately 3 dB compared with PI images and 2 dB compared with CPS images.

Conclusions
Acoustic radiation force can be used to generate adherent microbubble signal decorrelation without microbubble bursting. When combined with PI, measurements of the resulting microbubble signal decorrelation can be used to reconstruct images that exhibit superior suppression of highly echogenic tissue interfaces when compared with PI or CPS alone.
Scale-Free Exponents of Resting State are Biomarkers of Neuro-Typical and Atypical Brain Activity
Authors: Hanson S.J. , Mastrovito D. , Hanson C. , Ramsey J. , Glymour C. 
Published: August 2016

AbstractScale-free networks (SFN) arise from simple growth processes, which can encourage efficient, centralized and fault tolerant communication (1). Recently its been shown that stable network hub structure is governed by a phase transition at exponents (>2.0)causing a dramatic change in network structure including a loss of global connectivity, an increasing minimum dominating node set, and a shift towards increasing connectivity growth compared to node growth. Is this SFN shift identifiable in atypical brain activity? The Pareto Distribution (P(D)∼D∧-β) on the hub Degree (D) is a signature of scale-free networks. During resting-state, we assess Degree exponents across a large range of neurotypical and atypical subjects. We use graph complexity theory to provide a predictive theory of the brain network structure.Results.We show that neurotypical resting-state fMRI brain activity possess scale-free Pareto exponents(1.8 se .01)in a single individual scanned over 66 days as well as in 60 different individuals (1.8 se .02). We also show that 60 individuals with Autistic Spectrum Disorder, and 60 individuals with Schizophrenia have significantly higher (>2.0) scale-free exponents(2.4 se .03, 2.3 se .04), indicating more fractionated and less controllable dynamics in the brain networks revealed in resting state. Finally we show that the exponent values vary with phenotypic measures of atypical disease severity indicating that the global topology of the network itself can provide specific diagnostic biomarkers for atypical brain activity.
Modeling the Multiple Facets of Speciation-with-Gene-Flow Towards Inferring the Divergence History of Lake Whitefish Species Pairs (Coregonus Clupeaformis)
Authors: Rougeux Clément , Bernatchez Louis , Gagnaire Pierre-Alexandre 
Published: August 2016

AbstractParallel divergence patterns across replicated species pairs occurring in similar environmental contrasts may arise through distinct evolutionary scenarios. Deciphering whether such parallelism actually reflects repeated parallel divergence driven by divergent selection or a single divergence event with subsequent gene flow needs to be ascertained. Reconstructing historical gene flow is therefore of fundamental interest to understand how demography and selection jointly shaped genomic divergence during speciation. Here, we use an extended modeling framework to explore the multiple facets of speciation-with-gene-flow with demo-genetic divergence models that capture both temporal and genomic variation in effective population size and migration rate. We investigate the divergence history of five sympatric Lake Whitefish limnetic (dwarf) and benthic (normal) species pairs characterized by variable degrees of ecological divergence and reproductive isolation. Genome-wide SNPs were used to document the extent of genetic differentiation in each species pair, and 26 divergence models were fitted and compared to the unfolded joint allele frequency spectrum of each pair. We found evidence that a recent (circa 3000-4000 generations) asymmetrical secondary contact between expanding post-glacial populations has accompanied Whitefish diversification. Our results suggest that heterogeneous genomic differentiation patterns have emerged through the combined effects of linked selection generating variable rates of lineage sorting across the genome during geographical isolation, and heterogeneous introgression eroding divergence at different rates across the genome upon secondary contact. This study thus provides a new retrospective insight into the historical demographic and selective processes that shaped a continuum of divergence associated with ecological speciation.
The use of social media for engaging stakeholders in sustainability reporting
Authors: Manetti Giacomo , Bellucci Marco 
Published: August 2016

Purpose– The purpose of this paper is to assess if online interaction through social media, particularly Facebook, Twitter, and YouTube, represents an effective stakeholder engagement mechanism in order to define the contents of social, environmental, or sustainability reporting (SESR).Design/methodology/approach– After examining 332 worldwide sustainability reports for the year 2013, drawn up according to the guidelines provided by the Global Reporting Initiative, the authors conducted a content analysis on the Twitter, Facebook, and YouTube pages of the organisations who rely on these types of social media. This was done in order to assess the scope of interaction between the organisation and its stakeholders.Findings– The authors found that a small number of organisations use social media to engage stakeholders as a means of defining the contents of SESR, and that the level of interaction is generally low. Rather than assuming a deliberative approach that is aimed at forging a democratic consensus on how to address specific corporate social responsibility or SESR issues, these types of interaction focus on gathering divergent socio-political views in an agonistic perspective.Research limitations/implications– Further research could complement this exploratory research with statistical analyses. It could focus on how comments/replies by users are used by organisations and examine the impacts of SESR on companies’ performances.Originality/value– The authors contribute to the literature on social accounting by understanding whether social media can be reliable instruments of stakeholder engagement and by examining the relevance of information that is voluntarily disclosed by corporations in SESR.
The role of identity and image in shaping management accounting change
Authors: Taylor Lynda C. , Scapens Robert W. 
Published: August 2016

Purpose– The purpose of this paper is to analyse the implementation of a new accounting system in the accounting department of a large retail company. The paper seeks to understand and explain how management accounting change can be shaped by the identity and image of particular groups in an organisation.Design/methodology/approach– This paper reports the findings of a longitudinal explanatory case study. An institutional framework was initially used to inform the research, but was subsequently extended using the concepts of identity and image.Findings– By changing existing accounting systems, the accountants “inside” the accounting department sought to challenge their current “negative” identity and image. However, the case shows that the new accounting system was not well received by accountants “outside” the accounting department. The case illustrates that the differing identity and image of the two groups of accountants were crucial factors underlying the different perceptions of the accounting change.Originality/value– The conceptual framework developed in this paper highlights the role which identity and image can play in shaping processes of change, and it enriches the understanding of the reasons for change, stability and resistance to change.
The influence of USD/CNY foreign exchange rate, RMB NEER and spatial effects on China’s foreign trade
Authors: Wang Hua , Zhu Junjun 
Published: August 2016

Purpose– The purpose of this paper is to analyze the influence of different forms of RMB foreign exchange rates on Chinese foreign trade.Design/methodology/approach– This paper constructed spatial panel model and Markov Chain Monte Carlo estimation method and collected the data of 25 countries’ (including China) quarterly macroeconomic data from first quarter of 1993 until third quarter of 2013 to conduct the data analysis.Findings– This paper finds that USD/CNY, which is widely used in trade settlement, is more significant in effecting Chinese export. Totally, 1 percent appreciation of CNY against USD will lead to 1.532 percent decline of Chinese export, while 1 percent appreciation of CNY NEER only 0.42 percent. What is more, 1 percent increases of the volatility of USD/CNY results in 0.579 percent decline of Chinese export. As policy suggestions, we should further reform the foreign exchange derivative market in China, and provide more currency derivatives, so that the ability of Chinese economy to deal with foreign exchange risk could be improved.Research limitations/implications– Effect of exchange rate on imports and exports relates to the future direction of China’s exchange rate policy. This paper claims that China should accelerate the construction of foreign exchange derivatives market, improving the ability to respond quickly to foreign currency risk.Practical implications– First, denominated exchange rate has more significant impact on the Chinese export trade to other countries than effective exchange rate. Second, the RMB exchange rate fluctuations also significantly affect the export trade. Third, China’s import and export trade have significant spatial effect.Social implications– This paper recommends the construction of the RMB currency futures market as soon as possible, providing a richer foreign exchange derivatives and other risk hedging instruments, thus to enhance the ability to respond to exchange rate risks.Originality/value– This paper uses spatial panel model with the refined data to study various factors on the import and export trade, and thus more comprehensive analysis on the impact of the exchange rate on the import and export trade with other major countries.
The dependence structure in volatility between Shanghai and Shenzhen stock market in China
Authors: Guo Mingyuan , Wang Xu 
Published: August 2016

Purpose
– The purpose of this paper is to analyse the dependence structure in volatility between Shanghai and Shenzhen stock market in China based on high-frequency data.

Design/methodology/approach
– Using a multiplicative error model (hereinafter MEM) to describe the margins in volatility of China’s Shanghai and Shenzhen stock market, this study adopts static and time-varying copulas, respectively, estimated by maximum likelihood estimation method to describe the dependence structure in volatility between Shanghai and Shenzhen stock market in China.

Findings
– This paper has identified the asymmetrical dependence structure in financial market volatility more precisely. Gumbel copula could best fit the empirical distribution as it can capture the relatively high dependence degree in the upper tail part corresponding to the period of volatile price fluctuation in both static and dynamic view.

Originality/value
– Previous scholars mostly use GARCH model to describe the margins for price volatility. As MEM can efficiently characterize the volatility estimators, this paper uses MEM to model the margins for the market volatility directly based on high-frequency data, and proposes a proper distribution for the innovation in the marginal models. Then we could use copula-MEM other than copula-GARCH model to study on the dependence structure in volatility between Shanghai and Shenzhen stock market in China from a microstructural perspective.
Creation of cultural heritage inventories: case of the historic city of Ahmadabad
Authors: Shah Khushi 
Published: August 2016

Purpose
– The purpose of this paper is to illustrate the relevance of cultural heritage inventories and documentation as critical tools for heritage conservation and management in historic cities, through the case study of the historic city of Ahmadabad, India.

Design/methodology/approach
– The paper discusses the creation of inventories as part of the comprehensive documentation undertaken for preparation of the World Heritage nomination dossier. In this context, the goal of preserving the outstanding universal value of the historic city formed the basis for selection and assessment of the assets to be included in the inventory. Standard processes and methodology employed for creation of the database involved archival research and planning; field surveys for mapping, photo documentation and data collection; data registration and processing using CAD, Ms Office and geographic information system (GIS)-based digital platform. Optimal data acquisition while maintaining cost and time efficiency was an important consideration for the fieldwork.

Findings
– While an inventory remains a critical conservation tool, the heritage assets are integrally linked to and influenced by their surroundings in an urban context. A comprehensive documentation approach that provides a broader understanding of the city’s natural features, built environment, heritage resources, cultural practices and socio-economic networks is therefore necessary for creation of a suitable management plan for historic cities. Traditional field surveys based on external visual observation are time and cost effective, and can generate adequate information on identification and assessment of built heritage assets for creation of inventory along with documentation of their context. However, the scale of investigation and the intended role of an inventory as an urban management tool calls for creation of integrated, accessible and updatable data management systems.

Research limitations/implications
– At the moment, the database created is only used for the limited purpose of monitoring and managing the conservation of listed properties. The importance of the inventory as a critical conservation and urban management tool can be further validated once the GIS database of the historic city is integrated within the urban management and planning system for the city.

Originality/value
– The inventory created for the historic city of Ahmadabad offers one of the few examples of heritage documentation at such a large scale. It covers an area of 543 ha with a detailed inventory of more than 6,000 properties. The description of, and the reflections on the process employed provide an overview of usual challenges encountered in creation, presentation and management of heritage inventories for historic cities which may offer useful guidelines to practitioners planning similar exercises and help them establish efficient work processes.
Impulse buying tendencies among Indian consumers: scale development and validation
Authors: Mittal Sheetal , Chawla Deepak , Sondhi Neena 
Published: August 2016

Purpose
The purpose of this paper is to conceptualize, develop and validate the measurement of impulse buying tendency India, an emerging market in Asia.

Design/methodology/approach
The conceptualization of India’s impulse buying tendency (IBT) has been based on a review of academic literature and an analysis of qualitative data from 30 observations at retail stores and 25 in-depth consumer interviews. The scale’s reliability and validity were assessed by content, convergent, discriminant, nomological and predictive validity using statistical techniques such as exploratory factor analysis and confirmatory factor analysis.

Findings
A two-dimensional measure for IBT was developed for the Indian market, and then tested and validated using appropriate statistical measures.

Research limitations/implications
The study was skewed towards offline retail with both observations and interviews focusing on the bricks-and-mortar model. With e-retailing in India growing at a rapid rate, future research should extend the study and verify the IBT instrument’s validity specifically for impulse buying behaviour online.

Originality/value
To the best of authors’ knowledge, the present study is the first to bridge the gap in the existing research of impulse buying in context of emerging markets like India that are culturally, unlike both the western/developed and other Asian/emerging markets; and socio-economically, facing an interplay of variety of factors that are in a state of flux. The developed IBT scale would help by providing academics and practitioners with means of broadening their perspectives and understanding of retail behaviours in a context that is characterized by unprecedented consumer spending, increasing proliferation of modern retail and influence of a culture traditionally been given to simplicity and frugality.
Team mental model characteristics and performance in a simulation experiment
Authors: Yang Yi , Narayanan V.K. , Baburaj Yamuna , Swaminathan Srinivasan 
Published: August 2016

PurposeThis paper aims to examine the relationship between the characteristics of strategic decision-making team’s mental model and its performance. The authors propose that the relationship between mental models and performance is two-way, rather than one-way. Thus, performance feedback should, in turn, influence strategic behavior and future performance by either triggering or hindering the learning process.Design/methodology/approachThe authors conduct the research in the setting of a simulation experiment. A longitudinal data set was collected from 36 teams functioning as strategic decision makers over three periods.FindingsThis study provides support for the positive impacts of both the complexity and centrality of a team’s mental model on its performance. The authors also find that positive performance feedback reduces changes in complexity and centrality of team mental models due to cognitive inertia.Originality/valueThe study contributes to the literature by investigating the specific mechanisms that underlie mental model evolution. Different from the existing studies on team mental models that mainly focus on similarity of these shared cognitive structures, this study examines another two characteristics of team mental model, complexity and centrality, that are more relevant to the strategic decision-making process but has not been extensively studied in the team literature. In addition, this study reveals that performance feedback has different effects on team mental models depending on the referents – past performance or social comparison – which advances the understanding of the learning effects of performance feedback.