Differences in MEG and EEG power-law scaling explained by a coupling between spatial coherence and frequency: a simulation study

International audienceElectrophysiological signals (electroencephalography, EEG, and magnetoencephalography , MEG), as many natural processes, exhibit scale-invariance properties resulting in a power-law (1/f) spectrum. Interestingly, EEG and MEG differ in their slopes, which could be explained by several mechanisms, including non-resistive properties of tissues. Our goal in the present study is to estimate the impact of space/frequency structure of source signals as a putative mechanism to explain spectral scaling properties of neuroimaging signals. We performed simulations based on the summed contribution of cortical patches with different sizes (ranging from 0.4 to 104.2 cm 2). Small patches were attributed signals of high frequencies, whereas large patches were associated with signals of low frequencies, on a logarithmic scale. The tested parameters included i) the space/frequency structure (range of patch sizes and frequencies) and ii) the amplitude factor c parametrizing the spatial scale ratios. We found that the space/frequency structure may cause differences between EEG and MEG scale-free spectra that are compatible with real data findings reported in previous studies. We also found that below a certain spatial scale, there were no more differences between EEG and MEG, suggesting a limit for the resolution of both methods. Our work provides an explanation of experimental findings. This does not rule out other mechanisms for differences between EEG and MEG, but suggests an important role of spatio-temporal structure of neural dynamics. This can help the analysis and interpretation of power-law measures in EEG and MEG, and we believe our results can also impact computational modeling of brain dynamics, where different local connectivity structures could be used at different frequencies

Photo- and electroluminescence in a series of PPV type terpolymers containing fluorene, thiophene and phenylene units

The emissive properties of terpolymers with fluorene, thiophene and phenylene groups, forming alternating PPV type structures, are discussed in terms of their composition, photo- and electroluminescence properties. The fluorene groups were inserted in each phenylene-vinylene and thiophene-vinylene units, and their concentration did not vary, representing 50% of the molar composition. The ratio of thiophene-vinylene/phenylene-vinylene varied in the range 25,50 and 75%. Photo- and electroluminescence properties were strongly dependent on the thiophene-vinylene content and were compared with the fluorene-vinylene-thiophene and fluorene-vinylene-phenylene parent copolymers. (C) 2012 Elsevier B.V. All rights reserved

Review: Exploring the use of Precision Livestock Farming for small ruminant welfare management

Small ruminant (sheep and goat) production of meat and milk is undertaken in diverse topographical and climatic environments and the systems range from extensive to intensive. This could lead to different types of welfare compromise, which need to be managed. Implementing Precision Livestock Farming (PLF) and other new or innovative technologies could help to manage or monitor animal welfare. This paper explores such opportunities, seeking to identify promising aspects of PLF that may allow improved management of welfare for small ruminants using literature search (2 reviews), workshops in 9 countries (France, Greece, Ireland, Israel, Italy, Norway, Romania, Spain, and the United Kingdom) with 254 stakeholders, and panels with 52 experts. An investigation of the main welfare challenges that may affect sheep and goats across the different management systems in Europe was undertaken, followed by a prioritisation of animal welfare issues obtained in the 9 countries. This suggested that disease and health issues, feed access and undernutrition/malnutrition, maternal behaviour/offspring losses, environmental stressors and issues with agonistic behavioural interactions were important welfare concerns. These welfare issues and their indicators (37 for sheep, 25 for goats) were categorised into four broad welfare indicator categories: weight loss or change in body state (BWC), behavioural change (BC), milk yield and quality (MY), and environmental indicators (Evt). In parallel, 24 potential PLF and innovative technologies (8 for BWC; 10 for BC; 4 for MY; 6 for Evt) that could be relevant to monitor these broad welfare indicator categories and provide novel approaches to manage and monitor welfare have been identified. Some technologies had the capacity to monitor more than one broad indicator. Out of the 24 technologies, only 12 were animal-based sensors, or that could monitor the animal individually. One alternative could be to incorporate a risk management approach to welfare, using aspects of environmental stress. This could provide an early warning system for the potential risks of animal welfare compromise and alert farmers to the need to implement mitigation actions

Best practices for fNIRS publications

The application of functional near-infrared spectroscopy (fNIRS) in the neurosciences has been expanding over the last 40 years. Today, it is addressing a wide range of applications within different populations and utilizes a great variety of experimental paradigms. With the rapid growth and the diversification of research methods, some inconsistencies are appearing in the way in which methods are presented, which can make the interpretation and replication of studies unnecessarily challenging. The Society for Functional Near-Infrared Spectroscopy has thus been motivated to organize a representative (but not exhaustive) group of leaders in the field to build a consensus on the best practices for describing the methods utilized in fNIRS studies. Our paper has been designed to provide guidelines to help enhance the reliability, repeatability, and traceability of reported fNIRS studies and encourage best practices throughout the community. A checklist is provided to guide authors in the preparation of their manuscripts and to assist reviewers when evaluating fNIRS papers

Landscape of alcohol-related hepatocellular carcinoma in the last 15 years highlights the need to expand surveillance programs

Background & Aims: Alcohol abuse and metabolic disorders are leading causes of hepatocellular carcinoma (HCC) worldwide. Alcohol-related aetiology is associated with a worse prognosis compared with viral agents, because of the lower percentage of patients diagnosed with HCC under routine surveillance and a higher burden of comorbidity in alcohol abusers. This study aimed to describe the evolving clinical scenario of alcohol-related HCC over 15 years (2006–2020) in Italy. Methods: Data from the Italian Liver Cancer (ITA.LI.CA) registry were used: 1,391 patients were allocated to three groups based on the year of HCC diagnosis (2006–2010; 2011–2015; 2016–2020). Patient characteristics, HCC treatment, and overall survival were compared among groups. Survival predictors were also investigated. Results: Approximately 80% of alcohol-related HCCs were classified as cases of metabolic dysfunction-associated fatty liver disease. Throughout the quinquennia, <50% of HCCs were detected by surveillance programmes. The tumour burden at diagnosis was slightly reduced but not enough to change the distribution of the ITA.LI.CA cancer stages. Intra-arterial and targeted systemic therapies increased across quinquennia. A modest improvement in survival was observed in the last quinquennia, particularly after 12 months of patient observation. Cancer stage, HCC treatment, and presence of oesophageal varices were independent predictors of survival. Conclusions: In the past 15 years, modest improvements have been obtained in outcomes of alcohol-related HCC, attributed mainly to underuse of surveillance programmes and the consequent low amenability to curative treatments. Metabolic dysfunction-associated fatty liver disease is a widespread condition in alcohol abusers, but its presence did not show a pivotal prognostic role once HCC had developed. Instead, the presence of oesophageal varices, an independent poor prognosticator, should be considered in patient management and refining of prognostic systems. Impact and Implications: Alcohol abuse is a leading and growing cause of hepatocellular carcinoma (HCC) worldwide and is associated with a worse prognosis compared with other aetiologies. We assessed the evolutionary landscape of alcohol-related HCC over 15 years in Italy. A high cumulative prevalence (78%) of metabolic dysfunction-associated fatty liver disease, with signs of metabolic dysfunction, was observed in HCC patients with unhealthy excessive alcohol consumption. The alcohol + metabolic dysfunction-associated fatty liver disease condition tended to progressively increase over time. A modest improvement in survival occurred over the study period, likely because of the persistent underuse of surveillance programmes and, consequently, the lack of improvement in the cancer stage at diagnosis and the patients’ eligibility for curative treatments. Alongside the known prognostic factors for HCC (cancer stage and treatment), the presence of oesophageal varices was an independent predictor of poor survival, suggesting that this clinical feature should be carefully considered in patient management and should be included in prognostic systems/scores for HCC to improve their performance

New approach methodologies to enhance human health risk assessment of immunotoxic properties of chemicals: a PARC (Partnership for the Assessment of Risk from Chemicals) project

As a complex system governing and interconnecting numerous functions within the human body, the immune system is unsurprisingly susceptible to the impact of toxic chemicals. Toxicants can influence the immune system through a multitude of mechanisms, resulting in immunosuppression, hypersensitivity, increased risk of autoimmune diseases and cancer development. At present, the regulatory assessment of the immunotoxicity of chemicals relies heavily on rodent models and a limited number of Organisation for Economic Co-operation and Development (OECD) test guidelines, which only capture a fraction of potential toxic properties. Due to this limitation, various authorities, including the World Health Organization and the European Food Safety Authority have highlighted the need for the development of novel approaches without the use of animals for immunotoxicity testing of chemicals. In this paper, we present a concise overview of ongoing efforts dedicated to developing and standardizing methodologies for a comprehensive characterization of the immunotoxic effects of chemicals, which are performed under the EU-funded Partnership for the Assessment of Risk from Chemicals (PARC)

New approach methodologies to enhance human health risk assessment of immunotoxic properties of chemicals — a PARC (Partnership for the Assessment of Risk from Chemicals) project

As a complex system governing and interconnecting numerous functions within the human body, the immune system is unsurprisingly susceptible to the impact of toxic chemicals. Toxicants can influence the immune system through a multitude of mechanisms, resulting in immunosuppression, hypersensitivity, increased risk of autoimmune diseases and cancer development. At present, the regulatory assessment of the immunotoxicity of chemicals relies heavily on rodent models and a limited number of Organisation for Economic Co-operation and Development (OECD) test guidelines, which only capture a fraction of potential toxic properties. Due to this limitation, various authorities, including the World Health Organization and the European Food Safety Authority have highlighted the need for the development of novel approaches without the use of animals for immunotoxicity testing of chemicals. In this paper, we present a concise overview of ongoing efforts dedicated to developing and standardizing methodologies for a comprehensive characterization of the immunotoxic effects of chemicals, which are performed under the EU-funded Partnership for the Assessment of Risk from Chemicals (PARC)