bluuebunny/crossref_metadata_2025_split huggingface dataset:
A more accurate account of the effect of k-space sampling and signal decay on the effective spatial resolution in functional MRI
Authors: Chaimow Denis , Shmuel Amir 
Published: December 2016

AbstractThe effects of k-space sampling and signal decay on the effective spatial resolution of MRI and functional MRI (fMRI) are commonly assessed by means of the magnitude point-spread function (PSF), defined as the absolute values (magnitudes) of the complex MR imaging PSF. It is commonly assumed that this magnitude PSF signifies blurring, which can be quantified by its full-width at half-maximum (FWHM). Here we show that the magnitude PSF fails to accurately represent the true effects of k-space sampling and signal decay.Firstly, a substantial part of the width of the magnitude PSF is due to MRI sampling per se. This part is independent of any signal decay and its effect depends on the spatial frequency composition of the imaged object. Therefore, it cannot always be expected to introduce blurring. Secondly, MRI reconstruction is typically followed by taking the absolute values (magnitude image) of the reconstructed complex image. This introduces a non-linear stage into the process of image formation. Thecompleximaging PSF does not fully describe this process, since it does not reflect the stage of taking the magnitude image. Its correspondingmagnitudePSF fails to correctly describe this process, since convolving the original pattern with the magnitude PSF is different from the true process of taking the absolute following a convolution with the complex imaging PSF. Lastly, signal decay can have not only a blurring, but also a high-pass filtering effect. This cannot be reflected by the strictly positive width of the magnitude PSF.As an alternative, we propose to first approximate the MRI process linearly. We then model the linear approximation by decomposing it into a signal decay-independent MR sampling part and an approximation of the signal decay effect. We approximate the latter as a convolution with a Gaussian PSF or, if the effect is that of high-pass filtering, as reversing the effect of a convolution with a Gaussian PSF. We show that for typical high-resolution fMRI at 7 Tesla, signal decay in Spin-Echo has a moderate blurring effect (FWHM = 0.89 voxels, corresponds to 0.44 mm for 0.5 mm wide voxels). In contrast, Gradient-Echo acts as a moderate high-pass filter that can be interpreted as reversing a Gaussian blurring with FWHM = 0.59 voxels (0.30 mm for 0.5 mm wide voxels). Our improved approximations and findings hold not only for Gradient-Echo and Spin-Echo fMRI but also for GRASE and VASO fMRI. Our findings support the correct planning, interpretation, and modeling of high-resolution fMRI.
An efficient targeted nuclease strategy for high-resolution mapping of DNA binding sites
Authors: Skene Peter J. , Henikoff Steven 
Published: December 2016

AbstractWe describe Cleavage Under Targets and Release Using Nuclease (CUT&RUN), a chromatin profiling strategy in which antibody-targeted controlled cleavage by micrococcal nuclease releases specific protein-DNA complexes into the supernatant for paired-end DNA sequencing. Unlike Chromatin Immunoprecipitation (ChIP), which fragments and solubilizes total chromatin, CUT&RUN is performed in situ, allowing for both quantitative high-resolution chromatin mapping and probing of the local chromatin environment. When applied to yeast and human nuclei, CUT&RUN yielded precise transcription factor profiles while avoiding cross-linking and solubilization issues. CUT&RUN is simple to perform and is inherently robust, with extremely low backgrounds requiring only ~1/10ththe sequencing depth as ChIP, making CUT&RUN especially cost-effective for transcription factor and chromatin profiling. When used in conjunction with native ChIP-seq and applied to human CTCF, CUT&RUN mapped directional long range contacts at high resolution. We conclude that in situ mapping of protein-DNA interactions by CUT&RUN is an attractive alternative to ChIP-seq.
Electro-diffusion modulation of synaptic input in dendritic spines using deconvolved voltage sensor time series
Authors: Cartailler J. , Kwon T. , Yuste R. , Holcman D. 
Published: December 2016

AbstractThe inward current flowing inside the post-synaptic terminal of a neuron modulates transiently the membrane voltage potential. Most of the excitatory connections are made on dendritic spines characterized by a large variability in their geometry.How the voltage in a spine is modulated by geometry remains elusive due in part to the absence of direct measurements. To understand the spine voltage-current relation, we develop here a model for the voltage and we use it to extract electrical properties from live cell imaging data. We first deconvolve the genetically encoded voltage sensor expressed in hippocampal neurons and then use electro-diffusion theory, to compute the electric field and the ionic flows induced in a dendritic spine.The ionic flow is driven by the electric field coupled to the charge densities that interact through the non-cylindrical spine geometry. We determine the I-V relation and conclude that the spine effective resistance is mostly determined by the neck geometry. This modulation of synaptic inputs by the spine neck is significantly larger than what was expected from traditional cable models. Thus modulating the postsynaptic current can be achieved by changing the number of receptors or by altering the spine geometry which independently affects the transformation of current into voltage.Significance statementDendritic spines are geometrical structures receiving most of the excitatory transmission, yet how they modulate voltage from the synaptic current is not clear due to their submicron small size and specific non-cylindrical geometry. We study here the conversion of the synaptic current into voltage modulated by the spine geometry. Our approach is based on the electro-diffusion theory and we show that the spine neck is the main resistance filter, while the voltage is maintained constant in the head. Finally, we extract the effective resistance using a deconvolution of the genetically encoded voltage indicators expressed in hippocampal neurons. The present approach allows studying the electrical properties of many other structures such as glial small protrusions, cilia, and many others.
Spatial specificity of the functional MRI blood oxygenation response relative to neuronal activity
Authors: Chaimow Denis , Yacoub Essa , Uğurbil Kâmil , Shmuel Amir 
Published: December 2016

AbstractPrevious attempts at characterizing the spatial specificity of the blood oxygenation level dependent functional MRI (BOLD fMRI) response by estimating its point-spread function (PSF) have conventionally relied on spatial representations of visual stimuli in area V1. Consequently, their estimates were confounded by the width and scatter of receptive fields of V1 neurons. Here, we circumvent these limits by instead using the inherent cortical spatial organization of ocular dominance columns (ODCs) to determine the PSF for both Gradient Echo (GE) and Spin Echo (SE) BOLD imaging at 7 Tesla. By applying Markov Chain Monte Carlo sampling on a probabilistic generative model of imaging ODCs, we quantified the PSFs that best predict the spatial structure and magnitude of differential ODCs’ responses. Prior distributions for the ODC model parameters were determined by analyzing published data of cytochrome oxidase patterns from post-mortem histology of human V1 and of neurophysio-logical ocular dominance indices. The most probable PSF full-widths at halfmaximum were 0.82 mm (SE) and 1.02 mm (GE). Our results provide a quantitative basis for the spatial specificity of BOLD fMRI at ultra-high fields, which can be used for planning and interpretation of high-resolution differential fMRI of fine-scale cortical organizations.
Tracking stem cell differentiation without biomarkers using pattern recognition and phase contrast imaging
Authors: Delaney John D. , Nakatake Yuhki , Eckley D. Mark , Orlov Nikita V. , Coletta Christopher E. , Chen Chris , Ko Minoru S. , Goldberg Ilya G. 
Published: December 2016

AbstractBio-image informatics is the systematic application of image analysis algorithms to large image datasets to provide an objective method for accurately and consistently scoring image data. Within this field, pattern recognition (PR) is a form of supervised machine learning where the computer identifies relevant patterns in groups (classes) of images after being trained on examples. Rather than segmentation, image-specific algorithms or adjustable parameter sets, PR relies on extracting a common set of image descriptors (features) from the entire image to determine similarities and differences between image classes.Gross morphology can be the only available description of biological systems prior to their molecular characterization, but these descriptions can be subjective and qualitative. In principle, generalized PR can provide an objective and quantitative characterization of gross morphology, thus providing a means of computationally defining morphological biomarkers. In this study, we investigated the potential of a pattern recognition approach to a problem traditionally addressed using genetic or biochemical biomarkers. Often these molecular biomarkers are unavailable for investigating biological processes that are not well characterized, such as the initial steps of stem cell differentiation.Here we use a general contrast technique combined with generalized PR software to detect subtle differences in cellular morphology present in early differentiation events in murine embryonic stem cells (mESC) induced to differentiate by the overexpression of selected transcription factors. Without the use of reporters, ora prioriknowledge of the relevant morphological characteristics, we identified the earliest differentiation event (3 days), reproducibly distinguished eight morphological trajectories, and correlated morphological trajectories of 40 mESC clones with previous micro-array data. Interestingly, the six transcription factors that caused the greatest morphological divergence from an ESC-like state were previously shown by expression profiling to have the greatest influence on the expression of downstream genes.
Schumpeter and economic man
Authors: O’Boyle Edward John 
Published: December 2016

PurposeThe purpose of this paper is to examine the writings of Joseph Schumpeter on economic man to demonstrate that Schumpeter is a precursor of personalist economics.Design/methodology/approachThis paper addresses two intertwined questions. What evidence supports the claim that Schumpeter rejectedhomo economicus? What evidence indicates that Schumpeter actually embraced the human person – the acting person – as a replacement forhomo economicus? The evidence is presented in four sections: Schumpeter’s rejection ofhomo economicus; Schumpeter on economic agency; Schumpeter, a precursor of personalist economics; and final remarks.FindingsAs to the first question, there is no doubt that Schumpeter rejectedhomo economicus. Regarding the second, the evidence does not indicate that Schumpeter proposed replacinghomo economicuswith what today we refer to as the acting person. This paper concludes that by insisting on the critical role of the active, spontaneous, and eager-to-initiate change entrepreneur in economic affairs and our understanding of those affairs Schumpeter was a precursor of personalist economics.Originality/valueTo a large extent Schumpeter’s insights regarding economic agency and William Waters role in interpreting those insights have been buried in the economics literature. It was Waters in 1952 who stated that Schumpeter identified the inadequacy of economic man as the efficient cause of economic activity and re-established the human person as the true efficient cause, principally in terms of entrepreneurship.
Yoga and mindfulness for anxiety and depression and the role of mental health professionals: a literature review
Authors: Butterfield Nicole , Schultz Tim , Rasmussen Philippa , Proeve Michael 
Published: December 2016

Purpose
The purpose of this paper is to examine the role of yoga in the management of anxiety and depression, development of mindfulness and self-compassion and implications for mental health care delivery and mental health professionals, with a specific focus on nursing practice.

Design/methodology/approach
A search of electronic databases Scopus, CINAHL, EMBASE, Medline and Cochrane Library was undertaken.

Findings
There is growing research evidence supporting the use of yoga as an adjunct or combination therapy for the management of stress, anxiety and depression. Mindfulness has been indicated as a potential mechanism of change but needs further research. Health care professionals may play an important role in supporting consumers to engage in yoga as part of their mental health care.

Research limitations/implications
Yoga research to date has been limited by methodological weaknesses including wide variation of yoga practices, styles and teaching methods; difficulties in double-blinding, suitable placebo-control; lack of randomised controlled trials and small sample sizes. The literature highlights that more high-quality yoga and mental health research is needed.

Practical implications
The paper introduces the potential role of yoga for anxiety and depression in the health care system and the role of mental health professionals in implementing and promoting holistic yoga-based therapies.

Originality/value
This paper proposes a yoga model for mental health and provides insight into a proposed new direction for future mental health care and the role of nursing practice and other mental health professionals.
Mental health workers’ values and their congruency with recovery principles
Authors: Glajz Bianca A. , Deane Frank P. , Williams Virginia 
Published: December 2016

PurposeRecovery in mental health emphasises the empowerment of clients to discover and develop hope and a more satisfying life often in the presence of ongoing symptoms of mental illness. Work values that are incompatible with values that underpin the recovery philosophy may be contributing to the challenges in implementing recovery values in practice. The purpose of this paper is to explore the types of work values espoused by Australian mental health workers and their degree of congruence with recovery values.Design/methodology/approachIn total, 65 Australian mental health workers completed an open-ended work values question. Leximancer content analysis was used to generate a thematic work values profile followed by a theory-led thematic analysis of the responses to assess congruence with recovery values.FindingsThis sample valued client-centred practice that supports recovery, making a difference in others’ lives, work competence, being caring and empathic, and meaningful work. Overall, there was substantial congruence between work and recovery values, with less evidence of endorsement of values relating to strengths-based approaches, personal responsibility, and positive self-identity. These values should be targeted in future training initiatives.Originality/valueThe current study is the first study to identify the types of work values espoused by Australian mental health workers and to examine the degree to which they are recovery-consistent. This is an important research agenda given the high national and international priority to adopt a recovery orientation, and the need to identify and modify potential barriers to the implementation of recovery-oriented services.
Biogas production with co-digestion of sugarcane straw
Authors: De Rossi Eduardo , Lindino Cleber Antonio , Cremonez Paulo André , Dos Santos Kenia Gabriela , Bariccatti Reinaldo Aparecido , Antonelli Jhonatas , Teleken Joel Gustavo 
Published: December 2016

Purpose
The purpose of this paper is to investigate straw modification by chemical degradation generated by two forms of pretreatment, using citric acid in an autoclave and urea solution with sodium hydroxide at low temperature.

Design/methodology/approach
The material was digested and compared in biodigester reactors lined with natural straw, straw pretreated with citric acid, straw pretreated with urea and NaOH, and straw subjected to both the pretreatments. The amount of straw has been delimited to 0, 2.5, 5, 7.5 and 10 percent v/v, and used 20 percent v/v inoculum in all reactors, consisting of 30 percent v/v poultry litter and 70 percent swine wastewater (SW). The experiment was conducted in an incubator kept in mesophilic conditions (35°C).

Findings
The results indicate significant change in the studied material, with degradation of lignin as well as hemicellulose and cellulose exposed to further hydrolysis. Spectrophotometric methods were used for monitoring degradation. These methods were efficient in monitoring changes caused by the treatments. When the proposed pretreatments are applied to sugarcane straw, there is a significant gain in biogas production (L g VSR−1). The most appropriate rates for higher methane production in the pretreatments are 2.5 and 5 percent straw-SW. The best results for the anaerobic digestion of sugarcane straw were obtained by pretreating it with citric acid.

Originality/value
This paper shows a new use for the sugarcane straw waste after being pretreated with acid or base for the coproduction of biogas.
When one business model is not enough for a social business
Authors: Gebauer Heiko , Saul Caroline , Halidmann Mirella , Kramer Sasha 
Published: December 2016

Purpose
This paper aims to illustrate how managing multiple business models can become a key factor for succeeding in base-of-the-pyramid markets.

Design/methodology/approach
Case study was conducted through an engaged scholarship approach.

Findings
The authors highlight that companies can manage multiple business models, if they are following these three steps: recognition of costs-and-benefits, improvement and growth and creation of synergies.

Practical implications
The study provides guidance on how to manage multiple business models.

Social implications
This paper discusses Sustainable Organic Integrated Livelihoods, a social enterprise, which provides basic sanitation in bade-of-the-pyramid markets.

Originality/value
Operating more than one business model could cause often strategic failures. Sustainable Organic Integrated Livelihoods explored the advantages of having multiple business models in following three steps: recognition of costs-and-benefits, improvement and growth and creation of synergies.
Managing uncertainty: harnessing the power of scenario planning
Authors: Oliver John J. , Parrett Emma 
Published: December 2016

Purpose
This paper aims to provide an overview of the role that scenario planning can play in managing the uncertainty caused by changing and unpredictable competitive dynamics.

Design/methodology/approach
This viewpoint reflects both the practical experience of strategic planners, combined with an academic insight into the advantages of using scenario planning as a management tool.

Findings
Firms can develop corporate level strategy and gain long-term certainty in their strategic approach by using scenario planning to strategize in a way that allows them to prepare for multiple futures, with multiple strategies.

Practical implications
Firms can manage environmental uncertainty and turbulence by being “mentally prepared” to address the future by evaluating the critical uncertainties driving turbulence and the strategic options relevant to a number of possible future outcomes.

Originality/value
A unique combination of practical experience fused with academic knowledge on harnessing the power of scenario planning to manage uncertainty and develop organizational strategy.
Why leadership styles matter
Authors: Mauri Terence 
Published: December 2016

Purpose
This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies.

Design/methodology/approach
This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.

Findings
Leadership is undergoing a seismic and long overdue shift. In many companies, there is a chronic leadership gap: teams are being overmanaged and underled. To progress, leadership styles need to be updated; this means, we must be willing to change and become an avid learner of leadership.

Practical Implications
The paper provides strategic insights and practical thinking that have influenced some of the world’s leading organizations.

Originality/value
The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.
Political competition and de facto judicial independence in non‐democracies
Authors: EPPERLY BRAD 
Published: December 2016

AbstractThis article investigates the role of political competition in explaining de facto judicial independence in non‐democratic regimes. It argues that the electoral, political insurance explanation popular in the study of courts in democracies also offers explanatory power in the autocratic context, despite popular wisdom otherwise: due to the relatively greater risks of losing power in non‐democracies, electoral competition is highly salient when present. This is examined via hierarchical and fixed effects models that show competition strongly associated with increased levels of independence. This relationship is robust to alternative model and data specification, and has strong out‐of‐sample predictive accuracy.
Democracy without choice: Citizens’ perceptions of government autonomy during the Eurozone crisis
Authors: RUIZ‐RUFINO RUBÉN , ALONSO SONIA 
Published: December 2016

AbstractIn this article it is argued that citizens take into account the degree of a government's political autonomy to implement particular policies when expressing their views on satisfaction with democracy (SWD) but, in order to do so, they need to perceive it. When citizens directly observe the external constraints that reduce their government's autonomy, then variations in levels of regime satisfaction may no longer be exclusively about government performance – as widely argued by political economists – but also about democratic choice. The argument develops after comparing the existing scenarios in the Eurozone before and after the Great Recession. Citizens only began to perceive their own lack of choice to decide between policy alternatives when the sovereign debt crisis broke out in May 2010, the date of the first Greek bail‐out. It is then when citizens started to update their beliefs about the functioning of democracy as a system in which alternative policies can be adopted as bail‐out deals were signed between national governments from the Euro periphery and the Troika. This updating process towards the way democracy works explains the increasing gap in the levels of SWD between bailed‐out economies and the rest of the countries in the Eurozone. Empirical confirmation for this claim is found after analysing Eurobarometer surveys from 2002 to 2014 and using a two‐step difference‐in‐difference analysis that combines individual and aggregate data.