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Detection of antibiotic resistance gene mecA in foodborne Staphylococcus aureus with electrochemical biosensor
No full textInternational audienceThe increasing spread of antibiotic resistance and the transmission of antibiotic resistance genes require the urgent development of rapid and cost-effective detection methods. The food chain plays a significant role in the dissemination of resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). In this study, MRSA were isolated from milk and meat. A DNA MECA probe specific to the mecA gene was designed, evaluated in silico for specificity and experimentally through dot blot hybridization using DNA from S. aureus isolates confirmed by PCR. The probe was then integrated into an electrochemical biosensor based on Screen Printed gold Electrodes. In the absence of the target gene, the current signal stayed above baseline, whereas the presence of mecA gene resulted in a concentration-dependent decrease in signal, indicating effective hybridization within the range of 10 fg/mu L - 1 ng/mu L. Scanning electron microscopy analysis confirmed the presence of biological material exclusively on functionalized working electrode exposed to mecA-positive DNA. The system was further tested on S. aureus DNA extracted from 13 raw milk and meat matrices, demonstrating the biosensor's applicability for rapid (20-min), easy-to-perform, and low-cost detection of mecA gene. This work provides a promising basis for the development of on-site screening tools to monitor AR in the food production chain
Enhancing urban data exploration: Layer Toggling and Visibility-Preserving Lenses for multi-attribute spatial analysis
No full textInternational audienceThis manuscript proposes two novel interaction techniques for visualization-assisted exploration of urban data, namely, Layer Toggling and Visibility-Preserving Lenses. The former mitigates visual overload by organizing information into distinct layers while enabling multi-layer comparisons through controlled overlays. The technique supports focused analyses without sacrificing spatial context and enables users to quickly switch between layers through a dedicated physical button interface. Visibility-Preserving Lenses, on the other hand, dynamically adapt their size and transparency so that users can effectively examine dense spatial regions and temporal attributes in detail. Both techniques support urban data exploration and improve prediction.Exploring urban data is essential for understanding complex phenomena related to crime, mobility, and residents’ behavior and equally important is the ability to predict and explain how they evolve over time, supporting informed urban planning and policymaking. However, navigating urban data in all their complexity is challenging, often resulting in cognitive overload, loss of spatial context, and excessive visual clutter due to the many layers that must be examined simultaneously. Although layered visualizations aim to mitigate those challenges, they face limitations with occlusion and effortless comparisons across data layers. Additionally, interaction methods are typically confined to mouse-based controls, limiting the fluidity of dynamic exploration.The visualization tool was validated through a comprehensive user study that measured user performance, cognitive load, and interaction efficiency across multiple devices. Using real-world data from São Paulo, including mobility patterns, climate conditions, and crime statistics, the way the approach enhances both exploratory and analytical tasks is demonstrated. The results also show how users perform when playing with different interactive devices, providing guidelines for future developments and improvements
Community detection in a plant-based fermentation knowledge graph
No full textInternational audienceMicrobial data have rapidly expanded across diverse resources, including PubMed, omics datasets, and strain collections, creating a need for integration and standardization. To address this, Omnicrobe was developed, a relational database that regroups heterogeneous microbial information. From this resource, we extracted plant-based fermentationrelated data and represented them as a knowledge graph. This study investigates whether the structure of this graph contains sufficient signals to generate new biological hypotheses about fermentation processes. To evaluate this, we detect communities within the graph and perform a first evaluation of their characteristics
First Resolution of a Main-sequence G star’s Astrosphere Using Chandra
No full textInternational audienceWe report the resolution of a halo of X-ray line emission surrounding the zero-age main-sequence G8.5V star HD 61005 by Chandra/ACIS-S. Located only ∼36 pc distant, HD 61005 is young (100 ± 50 Myr) and X-ray bright (∼300 × solar), observed with a nearly edge-on geometry and surrounded by very local interstellar medium (VLISM) material denser than in the Sun's environs. HD 61005 is known to harbor large amounts of circumstellar dust in a dense ecliptic plane full of millimeter-sized particles plus attached, extended "Wing like structures" full of micron-sized particles, which are evidence for strong VLISM-dust disk interaction. These properties aided our ability to resolve the system's ∼220 au wide astrosphere, the first ever observed for a main-sequence G star. The observed X-ray emission morphology is roughly spherical, as expected for an astrospheric structure dominated by the host star. The Chandra spectrum of HD 61005 is a combination of a hard stellar coronal emission (T ∼ 8 MK) at L X ∼ 6 × 10 29 erg s -1 , plus an extended halo contribution at L X ∼ 1 × 10 29 erg s -1 dominated by charge exchange (CX) lines, such as those of O VIII and Ne IX. The Chandra CX X-ray morphology does not track the planar dust morphology but does extend out roughly to ∼110 au where the base of the dust wings begins. We present a toy model of the astrosphere emission produced by stellar wind-VLISM CX interactions, similar to the state of the young Sun when it was only ∼10 8 yr old and transiting through an ∼10 3 times denser part of the interstellar medium (such as a giant molecular cloud)
Is PI-RADS equally predictive across racial groups? A narrative review of mpMRI performance in Black versus White men
No full textInternational audienceBackgroundMultiparametric MRI (mpMRI) has become integral to prostate cancer (PCa) screening, improving detection and reducing unnecessary biopsies. This study investigated radiological disparities in mpMRI between Black and White PCa patients to improve diagnostic equity.MethodsA PubMed literature search was conducted using keywords related to prostate cancer, MRI, and racial disparities. Articles discussing mpMRI outcomes in White and Black PCa patients were selected.ResultsFrom 13 studies, two reported higher PI-RADS 4 and 5 scores among Black patients, while three showed higher proportions in White patients without increased clinically significant prostate cancer (csPCa). Clinically significant prostate cancer (csPCa) defined as ISUP Grade Group ≥ 2. The csPCa detection rate in Black patients was equal to or higher than in White patients, with some studies showing more PI-RADS 3 lesions among Black patients with csPCa. Key findings include: 1. Development bias: PI-RADS may not account for racial variations. 2. Inconsistent lesion detection across racial groups. 3. Lower PI-RADS scores may mask clinically relevant cancer in Black patients. 4. Inadequate representation of the disease in Black men. Anatomical variations may affect lesion visibility, requiring dedicated imaging-pathology studies.ConclusionWhile valuable for PCa detection, current mpMRI applications may contribute to racial disparities and biopsies should not be omitted in black patients with negative mpMRI or PIRADS 3 lesions. Addressing these disparities requires inclusive research and consideration of racial variations in diagnostic pathways
When liquids move on solids: unexpected deep liquid-solid THz coupling
No full textInternational audienc
Approaches to Exceptional Points in the Framework of Non-Hermitian Random Matrices
No full textInternational audienceWe explore how easy it is to enforce the advent of exceptional points starting from random matrices of non-Hermitian nature. We use the Petermann factor, whose mathematical version is called “overlap”, for guidance, as well as simple pseudo-spectral tools. We attempt to proceed in the most agnostic way, by adding random perturbation and checking basic metrics such as the sum of all vectors’ Petermann factors, equivalently the sum of diagonal overlaps. Issues such as the location of high Petermann factors vs. the modulus of eigenvalue are addressed. We contrast the fate of exploratory approaches in the Ginibre set (real matrices) and complex matrices, noting the special role of exceptional points on the real axis for the Ginibre matrices, completely absent in complex matrices
The multiloop sunset to all orders
No full text28 pages. Implementation code available at https://github.com/pierrevanhove/AllLoopSunset?tab=readme-ov-fil
Protocol for a cohort comparison treatment study evaluating the efficacy of a dimensional adaptation of GPM (GPM-extended) compared to a classic outpatient GPM treatment for patient fulfilling criteria for BPD: the EPSYLIA project
No full textInternational audiencePersonality disorders (PD) are common and debilitating psychiatric conditions, often characterized by severe interpersonal and self-dysfunction. Borderline personality disorder (BPD) is the most studied PD, with treatments like Good Psychiatric Management (GPM) demonstrating effectiveness. To address the current state of the personality disorder field, where most evidence-based treatments have been developed using a categorical approach, while the most empirically supported approach is the dimensional one, we developed an adaptation of GPM (GPM-extended) integrating concepts of dimensional personality dysfunction into an established therapeutic framework. This prospective “here-there” study will compare GPM-extended with standard GPM in two outpatient facilities. This methodological choice is due to organizational and institutional limitations. Participants (≥18 years) meeting BPD criteria per the SCID-II will be included. The GPM-extended group incorporates a dimensional diagnostic framework focusing on three personality dilemmas (rejection/abandonment fears, self-esteem dysregulation, and perfection/control issues), with tailored psychoeducation and treatment priorities. The standard GPM group will follow the validated GPM protocol, emphasizing interpersonal hypersensitivity and standard psychoeducation. Both groups will receive weekly individual therapy and group interventions for one year. Between-group differences at 1-year follow-up will be assessed using multiple regression models adjusted for baseline scores. The primary outcome is the change in BPD symptom severity (ZAN-BPD). Secondary outcomes include personality functioning, traits, and various clinical dimensions such as impulsivity, emotional regulation, and social functioning. All patients having initiated the program and having initial data will be included in the analysis, with multiple imputations for missing data and sensitivity analyses planned. Altogether, this study seeks to evaluate the feasibility and efficacy of integrating dimensionality into GPM, offering a pragmatic pathway to improve PD treatment and bridging gaps between evidence-based conceptualizations and treatments of PD
Defining Alzheimer's disease: stipulations and the ethics of diagnostic change
No full textInternational audienceRecent revisions of Alzheimer’s Disease (AD) definitions by two leading research groups—the Alzheimer’s Association and the International Working Group—reflect divergent approaches: the former promotes a strictly biological definition, while the latter promotes a clinicalbiological construct. We contend that this emerging controversy is not merely semantic, but scientifically, clinically, and politically significant. Drawing on philosophical tools and situating the current debate within a broader historical context from the reconceptualization of AD in the 1970s onwards, we explore how definitions can serve as transformative instruments, acting as strategic bets that reshape scientific fields and clinical practices. Ultimately, we draw from the AD case study to argue for a critical reflection on the risks and promises of such definitional acts. We also propose a renewed attention to the 'ethics of stipulating' in the field of contemporary biomedical sciences