915 research outputs found
All-for-One and One-For-All: Deep learning-based feature fusion for Synthetic Speech Detection
Recent advances in deep learning and computer vision have made the synthesis
and counterfeiting of multimedia content more accessible than ever, leading to
possible threats and dangers from malicious users. In the audio field, we are
witnessing the growth of speech deepfake generation techniques, which solicit
the development of synthetic speech detection algorithms to counter possible
mischievous uses such as frauds or identity thefts. In this paper, we consider
three different feature sets proposed in the literature for the synthetic
speech detection task and present a model that fuses them, achieving overall
better performances with respect to the state-of-the-art solutions. The system
was tested on different scenarios and datasets to prove its robustness to
anti-forensic attacks and its generalization capabilities.Comment: Accepted at ECML-PKDD 2023 Workshop "Deep Learning and Multimedia
Forensics. Combating fake media and misinformation
A Data-Driven Approach to Violin Making
Of all the characteristics of a violin, those that concern its shape are
probably the most important ones, as the violin maker has complete control over
them. Contemporary violin making, however, is still based more on tradition
than understanding, and a definitive scientific study of the specific relations
that exist between shape and vibrational properties is yet to come and sorely
missed. In this article, using standard statistical learning tools, we show
that the modal frequencies of violin tops can, in fact, be predicted from
geometric parameters, and that artificial intelligence can be successfully
applied to traditional violin making. We also study how modal frequencies vary
with the thicknesses of the plate (a process often referred to as {\em plate
tuning}) and discuss the complexity of this dependency. Finally, we propose a
predictive tool for plate tuning, which takes into account material and
geometric parameters
TIMIT-TTS: a Text-to-Speech Dataset for Multimodal Synthetic Media Detection
With the rapid development of deep learning techniques, the generation and
counterfeiting of multimedia material are becoming increasingly straightforward
to perform. At the same time, sharing fake content on the web has become so
simple that malicious users can create unpleasant situations with minimal
effort. Also, forged media are getting more and more complex, with manipulated
videos that are taking the scene over still images. The multimedia forensic
community has addressed the possible threats that this situation could imply by
developing detectors that verify the authenticity of multimedia objects.
However, the vast majority of these tools only analyze one modality at a time.
This was not a problem as long as still images were considered the most widely
edited media, but now, since manipulated videos are becoming customary,
performing monomodal analyses could be reductive. Nonetheless, there is a lack
in the literature regarding multimodal detectors, mainly due to the scarsity of
datasets containing forged multimodal data to train and test the designed
algorithms. In this paper we focus on the generation of an audio-visual
deepfake dataset. First, we present a general pipeline for synthesizing speech
deepfake content from a given real or fake video, facilitating the creation of
counterfeit multimodal material. The proposed method uses Text-to-Speech (TTS)
and Dynamic Time Warping techniques to achieve realistic speech tracks. Then,
we use the pipeline to generate and release TIMIT-TTS, a synthetic speech
dataset containing the most cutting-edge methods in the TTS field. This can be
used as a standalone audio dataset, or combined with other state-of-the-art
sets to perform multimodal research. Finally, we present numerous experiments
to benchmark the proposed dataset in both mono and multimodal conditions,
showing the need for multimodal forensic detectors and more suitable data
Arrhythmic risk in elderly patients candidates to transcatheter aortic valve replacement. predicative role of repolarization temporal dispersion
Degenerative aortic valve stenosis (AS) is associated to ventricular arrhythmias and sudden cardiac death, as well as mental stress in specific patients. In such a context, substrate, autonomic imbalance as well as repolarization dispersion abnormalities play an undoubted role. Aim of the study was to evaluate the increase of premature ventricular contractions (PVC) and complex ventricular arrhythmias during mental stress in elderly patients candidate to the transcatheter aortic valve replacement (TAVR). In eighty-one elderly patients with AS we calculated several short-period RRand QT-derived variables at rest, during controlled breathing and during mild mental stress, the latter being represented by a mini-mental state evaluation (MMSE). All the myocardial repolarization dispersion markers worsened during mental stress (p < 0.05). Furthermore, during MMSE, low frequency component of the RR variability increased significantly both as absolute power (LFRR) and normalized units (LFRRNU) (p < 0.05) as well as the low-high frequency ratio (LFRR/HFRR) (p < 0.05). Eventually, twenty-four (30%) and twelve (15%) patients increased significantly PVC and, respectively, complex ventricular arrhythmias during the MMSE administration. At multivariate logistic regression analysis, the standard deviation of QTend (QTesd), obtained at rest, was predictive of increased PVC (odd ratio: 1.54, 95% CI 1.14–2.08; p = 0.005) and complex ventricular arrhythmias (odd ratio: 2.31, 95% CI 1.40–3.83; p = 0.001) during MMSE. The QTesd showed the widest sensitive-specificity area under the curve for the increase of PVC (AUC: 0.699, 95% CI: 0.576–0.822, p < 0.05) and complex ventricular arrhythmias (AUC: 0.801, 95% CI: 0.648–0.954, p < 0.05). In elderly with AS ventricular arrhythmias worsened during a simple cognitive assessment, this events being a possible further burden on the outcome of TAVR. QTesd might be useful to identify those patients with the highest risk of ventricular arrhythmias. Whether the TAVR could led to a QTesd reduction and, hence, to a reductionof thearrhythmicburdenin thissettingofpatients isworthytobe investigated
Impact of Stain Normalization on Pathologist Assessment of Prostate Cancer: A Comparative Study
In clinical routine, the quality of whole-slide images plays a key role in the pathologist’s diagnosis, and suboptimal staining may be a limiting factor. The stain normalization process helps to solve this problem through the standardization of color appearance of a source image with respect to a target image with optimal chromatic features. The analysis is focused on the evaluation of the following parameters assessed by two experts on original and normalized slides: (i) perceived color quality, (ii) diagnosis for the patient, (iii) diagnostic confidence and (iv) time required for diagnosis. Results show a statistically significant increase in color quality in the normalized images for both experts (p < 0.0001). Regarding prostate cancer assessment, the average times for diagnosis are significantly lower for normalized images than original ones (first expert: 69.9 s vs. 77.9 s with p < 0.0001; second expert: 37.4 s vs. 52.7 s with p < 0.0001), and at the same time, a statistically significant increase in diagnostic confidence is proven. The improvement of poor-quality images and greater clarity of diagnostically important details in normalized slides demonstrate the potential of stain normalization in the routine practice of prostate cancer assessment
Evaluation of DNA methylation levels of SEPT9 and SHOX2 in plasma of patients with head and neck squamous cell carcinoma using droplet digital PCR
Head and neck squamous cell carcinoma (HNSCC) is the seventh most commonly diagnosed cancer globally. HNSCC develops from the mucosa of the oral cavity, pharynx and larynx. Methylation levels of septin 9 (SEPT9) and short stature homeobox 2 (SHOX2) genes in circulating cell‐free DNA (ccfDNA) are considered epigenetic biomarkers and have shown predictive value in preliminary reports in HNSCC. Liquid biopsy is a non‐invasive procedure that collects tumor‐derived molecules, including ccfDNA. In the present study, a droplet digital PCR (ddPCR)‐based assay was developed to detect DNA methylation levels of circulating SEPT9 and SHOX2 in the plasma of patients with HNSCC. The assay was first set up using commercial methylated and unmethylated DNA. The dynamic changes in the methylation levels of SEPT9 and SHOX2 were then quantified in 20 patients with HNSCC during follow‐up. The results highlighted: i) The ability of the ddPCR‐based assay to detect very low copies of methylated molecules; ii) the significant decrease in SEPT9 and SHOX2 methylation levels in the plasma of patients with HNSCC at the first time points of follow‐up with respect to T0; iii) a different trend of longitudinally DNA methylation variations in small groups of stratified patients. The absolute and precise quantification of SEPT9 and SHOX2 methylation levels in HNSCC may be useful for studies with translational potential
SARS-CoV-2-Associated ssRNAs Activate Human Neutrophils in a TLR8-Dependent Fashion
COVID-19 disease is characterized by a dysregulation of the innate arm of the immune system. However, the mechanisms whereby innate immune cells, including neutrophils, become activated in patients are not completely understood. Recently, we showed that GU-rich RNA sequences from the SARS-CoV-2 genome (i.e., SCV2-RNA1 and SCV2-RNA2) activate dendritic cells. To clarify whether human neutrophils may also represent targets of SCV2-RNAs, neutrophils were treated with either SCV2-RNAs or, as a control, R848 (a TLR7/8 ligand), and were then analyzed for several functional assays and also subjected to RNA-seq experiments. Results highlight a remarkable response of neutrophils to SCV2-RNAs in terms of TNFα, IL-1ra, CXCL8 production, apoptosis delay, modulation of CD11b and CD62L expression, and release of neutrophil extracellular traps. By RNA-seq experiments, we observed that SCV2-RNA2 promotes a transcriptional reprogramming of neutrophils, characterized by the induction of thousands of proinflammatory genes, similar to that promoted by R848. Furthermore, by using CU-CPT9a, a TLR8-specific inhibitor, we found that SCV2-RNA2 stimulates neutrophils exclusively via TLR8-dependent pathways. In sum, our study proves that single-strand RNAs from the SARS-CoV-2 genome potently activate human neutrophils via TLR8, thus uncovering a potential mechanism whereby neutrophils may contribute to the pathogenesis of severe COVID-19 disease
- …