224 research outputs found
Deepfakes: trick or treat?
Although manipulations of visual and auditory media are as old as the media themselves, the recent entrance of deepfakes has marked a turning point in the creation of fake content. Powered by latest technological advances in AI and machine learning, they offer automated procedures to create fake content that is harder and harder to detect to human observers. The possibilities to deceive are endless, including manipulated pictures, videos and audio, that will have large societal impact. Because of this, organizations need to understand the inner workings of the underlying techniques, as well as their strengths and limitations. This article provides a working definition of deepfakes together with an overview of the underlying technology. We classify different deepfake types: photo (face- and body-swapping), audio (voice-swapping, text to speech), video (face-swapping, face-morphing, full body puppetry) and audio and video (lip-synching), and identify risks and opportunities to help organizations think about the future of deepfakes. Finally, we propose the R.E.A.L. framework to manage deepfake risks: Record original content to assure deniability, Expose deepfakes early, Advocate for legal protection and Leverage trust to counter credulity. Following these principles, we hope that our society can be more prepared to counter the deepfake tricks as we appreciate its treats
Making sense of text: artificial intelligence-enabled content analysis
Purpose: The purpose of this paper is to introduce, apply and compare how artificial intelligence (AI), and specifically the IBM Watson system, can be used for content analysis in marketing research relative to manual and computer-aided (non-AI) approaches to content analysis.
Design/methodology/approach: To illustrate the use of AI-enabled content analysis, this paper examines the text of leadership speeches, content related to organizational brand. The process and results of using AI are compared to manual and computer-aided approaches by using three performance factors for content analysis: reliability, validity and efficiency.
Findings: Relative to manual and computer-aided approaches, AI-enabled content analysis provides clear advantages with high reliability, high validity and moderate efficiency.
Research limitations/implications: This paper offers three contributions. First, it highlights the continued importance of the content analysis research method, particularly with the explosive growth of natural language-based user-generated content. Second, it provides a road map of how to use AI-enabled content analysis. Third, it applies and compares AI-enabled content analysis to manual and computer-aided, using leadership speeches.
Practical implications: For each of the three approaches, nine steps are outlined and described to allow for replicability of this study. The advantages and disadvantages of using AI for content analysis are discussed. Together these are intended to motivate and guide researchers to apply and develop AI-enabled content analysis for research in marketing and other disciplines.
Originality/value: To the best of the authors' knowledge, this paper is among the first to introduce, apply and compare how AI can be used for content analysis
Análisis de cadenas de Markov y series de Fourier en una secuencia hemipelágica del Jurásico Superior de la Península Antártica
La Formación Ameghino (Kimmeridgiano-Berriasiano), Cuenca Larsen, Península Antártica, está compuesta por una asociación de microfacies de pelitas con radiolarios (P1), pelitas negras (P2), pelitas bioturbadas y peloidales (P3), tobas (T) y areniscas (A) excelentemente preservadas. Este conjunto de microfacies revela sedimentación pelágica/ hemipelágica en un ambiente deficiente en oxígeno, periódicamente interrumpida por caídas de cenizas del arco volcánico antártico. Análisis basados en cadenas de Markov indican la recurrencia de las microfacies y sus relaciones cíclicas. Se interpreta que la alternancia de pelitas con radiolarios y pelitas negras (P1-P2) responde a variaciones en la productividad/dilución, mientras que las microfacies de tobas y areniscas corresponden a depósitos de evento que modificaron las condiciones ambientales y diagenéticas evitando la disolución de los esqueletos de radiolarios en la masa de agua y en el fondo, y generando de este modo una memoria markoviana con ciclos T-P1-P2. Por otra parte, el análisis por transformadas de Fourier indica para los ciclos P1-P2 una duración del orden de 1000 años, en el rango de variaciones sub-Milankovitch
Cold atmospheric pressure plasma for treatment of chronic wounds: drug or medical device?
Objective:
The use of cold atmospheric pressure plasma (CAPP) as a new therapeutic option to aid the healing of chronic wounds appears promising. Currently, uncertainty exists regarding their classification as medical device or medical drug. Because the classification of CAPP has medical, legal, and economic consequences as well as implications for the level of preclinical and clinical testing, the correct classification is not an academic exercise, but an ethical need.
Method:
A multidisciplinary team of physicians, surgeons, pharmacists, physicists and lawyers has analysed the physical and technical characteristics as well as legal conditions of the biological action of CAPP.
Results:
It was concluded that the mode of action of the locally generated CAPP, with its main active components being different radicals, is pharmacological and not physical in nature.
Conclusion:
Depending on the intended use, CAPP should be classified as a drug, which is generated by use of a medical device directly at the point of therapeutic application
Building Online Platforms for Peer Support Groups as a Persuasive Behavioural Change Technique
Online peer group approach is inherently a persuasive technique as it is centered on peer pressure and surveillance. They are persuasive social net- works equipped with tools and facilities that enable behaviour change. This paper presents the case for domain-specific persuasive social networks and provides insights on problematic and addictive behaviour change. A 4-month study was conducted in an addiction rehab centre in the UK, followed by 2-month study in an online peer group system. The study adopted qualitative methods to under- stand the broad parameters of peer groups including the sessions' environment, norms, interaction styles occurring between groups' members and how such in- teractions are governed. The qualitative techniques used were (1) observations, (2) form and document analysis, and (3) semi-structured interviews. The findings concern governing such groups in addition to the roles to be enabled and tasks to be performed. The Honeycomb framework was revisited to comment on its build- ing blocks with the purpose of highlighting points to consider when building do- main-specific social networks for such domain, i.e. online peer groups to combat addictive behaviour
Collection of Aerosolized Human Cytokines Using Teflon® Filters
Background: Collection of exhaled breath samples for the analysis of inflammatory biomarkers is an important area of research aimed at improving our ability to diagnose, treat and understand the mechanisms of chronic pulmonary disease. Current collection methods based on condensation of water vapor from exhaled breath yield biomarker levels at or near the detection limits of immunoassays contributing to problems with reproducibility and validity of biomarker measurements. In this study, we compare the collection efficiency of two aerosol-to-liquid sampling devices to a filter-based collection method for recovery of dilute laboratory generated aerosols of human cytokines so as to identify potential alternatives to exhaled breath condensate collection. Methodology/Principal Findings: Two aerosol-to-liquid sampling devices, the SKC® Biosampler and Omni 3000™, as well as Teflon® filters were used to collect aerosols of human cytokines generated using a HEART nebulizer and single-pass aerosol chamber setup in order to compare the collection efficiencies of these sampling methods. Additionally, methods for the use of Teflon® filters to collect and measure cytokines recovered from aerosols were developed and evaluated through use of a high-sensitivity multiplex immunoassay. Our results show successful collection of cytokines from pg/m3 aerosol concentrations using Teflon® filters and measurement of cytokine levels in the sub-picogram/mL concentration range using a multiplex immunoassay with sampling times less than 30 minutes. Significant degradation of cytokines was observed due to storage of cytokines in concentrated filter extract solutions as compared to storage of dry filters. Conclusions: Use of filter collection methods resulted in significantly higher efficiency of collection than the two aerosol-to-liquid samplers evaluated in our study. The results of this study provide the foundation for a potential new technique to evaluate biomarkers of inflammation in exhaled breath samples
The Circadian Clock Protein CRY1 Is a Negative Regulator of HIF-1 alpha
The circadian clock and the hypoxia-signaling pathway are regulated by an integrated interplay of positive and negative feedback limbs that incorporate energy homeostasis and carcinogenesis. We show
that the negative circadian regulator CRY1 is also a negative regulator of hypoxia-inducible factor
(HIF). Mechanistically, CRY1 interacts with the basic-helix-loop-helix domain of HIF-1a via its tail region. Subsequently, CRY1 reduces HIF-1a half-life and binding of HIFs to target gene promoters.
This appeared to be CRY1 specific because genetic disruption of CRY1, but not CRY2, affected the
hypoxia response. Furthermore, CRY1 deficiency could induce cellular HIF levels, proliferation, and
migration, which could be reversed by CRISPR/Cas9- or short hairpin RNA-mediated HIF knockout.
Altogether, our study provides a mechanistic explanation for genetic association studies linking a
disruption of the circadian clock with hypoxia-associated processes such as carcinogenesis
Expression pattern of the urokinase-plasminogen activator system in rat DS-sarcoma: Role of oxygenation status and tumour size
The urokinase plasminogen activator system plays a central role in malignant tumour progression. Both tumour hypoxia and enhancement of urokinase plasminogen activator, urokinase plasminogen activator-receptor and plasminogen activator inhibitor type 1 have been identified as adverse prognostic factors. Upregulation of urokinase plasminogen activator or plasminogen activator inhibitor type 1 could present means by which hypoxia influences malignant progression. Therefore, the impact of hypoxia on the expression pattern of the urokinase plasminogen activator system in rat DS-sarcoma in vivo and in vitro was examined. In the in vivo setting, tumour cells were implanted subcutaneously into rats, which were housed under either hypoxia, atmospheric air or hyperoxia. For in vitro studies, DS-sarcoma cells were incubated for 24 h under hypoxia. Urokinase plasminogen activator and urokinase plasminogen activator-receptor expression were analysed by flow cytometry. Urokinase plasminogen activator activity was measured using zymography. Plasminogen activator inhibitor type 1 protein levels in vitro and in vivo were examined with ELISA. PAI-1 mRNA levels were determined by RT–PCR. DS-sarcoma cells express urokinase plasminogen activator, urokinase plasminogen activator-receptor, and plasminogen activator inhibitor type 1 in vitro and in vivo. The urokinase plasminogen activator activity is enhanced in DS-sarcomas compared to normal tissues and rises with increasing tumour volume. The oxygenation level has no impact on the urokinase plasminogen activator activity in cultured DS-sarcoma cells or in solid tumours, although in vitro an increase in plasminogen activator inhibitor type 1 protein and mRNA expression after hypoxic challenge is detectable. The latter plasminogen activator inhibitor type 1 changes were not detectable in vivo. Hypoxia has been demonstrated to contribute to the upregulation of some components of the system in vitro, although this effect was not reproducible in vivo. This may indicate that the serum level of plasminogen activator inhibitor type 1 is not a reliable surrogate marker of tumour hypoxia
Measures and Limits of Models of Fixation Selection
Models of fixation selection are a central tool in the quest to understand how the human mind selects relevant information. Using this tool in the evaluation of competing claims often requires comparing different models' relative performance in predicting eye movements. However, studies use a wide variety of performance measures with markedly different properties, which makes a comparison difficult. We make three main contributions to this line of research: First we argue for a set of desirable properties, review commonly used measures, and conclude that no single measure unites all desirable properties. However the area under the ROC curve (a classification measure) and the KL-divergence (a distance measure of probability distributions) combine many desirable properties and allow a meaningful comparison of critical model performance. We give an analytical proof of the linearity of the ROC measure with respect to averaging over subjects and demonstrate an appropriate correction of entropy-based measures like KL-divergence for small sample sizes in the context of eye-tracking data. Second, we provide a lower bound and an upper bound of these measures, based on image-independent properties of fixation data and between subject consistency respectively. Based on these bounds it is possible to give a reference frame to judge the predictive power of a model of fixation selection . We provide open-source python code to compute the reference frame. Third, we show that the upper, between subject consistency bound holds only for models that predict averages of subject populations. Departing from this we show that incorporating subject-specific viewing behavior can generate predictions which surpass that upper bound. Taken together, these findings lay out the required information that allow a well-founded judgment of the quality of any model of fixation selection and should therefore be reported when a new model is introduced
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