Biology subjects

Meghdadi, A.

Publications and source records attributed to Meghdadi, A..

3 recordsLinked to original sources

bioRxiv2025

A High-Dimensional Interfacial Wave Assay for Early Biophysical Profiling of Therapeutic Antibodies

Therapeutic antibody performance depends not only on sequence and structure, but also on how the molecule responds to physico-chemical perturbations encountered in its environment. Whereas sequence and static structure can be inferred under controlled conditions, behaviour is a conditional, multidimensional response to environment, most directly characterised by applying defined perturbations and quantifying the resulting dynamics. Conventional early-stage developability methods capture isolated dimensions of this response under near-equilibrium conditions, deferring integrated behavioural assessment to late-stage characterisation, when the cost of correction is highest. We introduce Variations in Interfacial Behaviour under Excitation (VIBE), an interfacial wave method implemented via Liquid State Intelligence (LSI), a sensing architecture that transduces molecular perturbations at the air-liquid interface into high-dimensional wave patterns. A colloidal liquid substrate operated near a thermodynamic transition couples small molecular perturbations to large dynamical responses, integrating structural flexibility, charge distribution, and surface hydrophobicity into a single behavioural readout from microgram-scale samples. Applied to antibodies previously characterised by industrial benchmarks, the primary behavioural descriptor, VIBE1, functioned as a high-precision triage tool, flagging candidates carrying multiple biophysical liabilities. In a clinical-stage cohort, the proportion of high-VIBE1 antibodies declined progressively from early trials through approval, and high-VIBE1 candidates showed an elevated clinical failure rate. Concordance analysis against estab-lished methods confirmed that VIBE1 captures a composite signal spanning hydrophobicity, polyreactivity, self-interaction, and thermal stability rather than recapitulating any single conventional readout. These findings establish interfacial wave sensing as a low-material modality for early-stage developability assessment, repositioning molecular behaviour from late-stage validation to discovery-phase characterisation.

biophysics↗

bioRxiv2021

Intermittent brain network reconfigurations and the resistance to social media influence

Since their development, social media has grown as a source of information and has a significant impact on opinion formation. Individuals interact with others and content via social media platforms in a variety of ways but it remains unclear how decision making and associated neural processes are impacted by the online sharing of informational content, from factual to fabricated. Here, we use EEG to estimate dynamic reconfigurations of brain networks and probe the neural changes underlying opinion change (or formation) within individuals interacting with a simulated social media platform. Our findings indicate that the individuals who changed their opinions are characterized by less frequent network reconfigurations while those who did not change their opinions tend to have more flexible brain networks with frequent reconfigurations. The nature of these frequent network configurations suggests a fundamentally different thought process between intervals in which individuals are easily influenced by social media and those in which they are not. We also show that these reconfigurations are distinct to the brain dynamics during an in-person discussion with strangers on the same content. Together, these findings suggest that brain network reconfigurations may not only be diagnostic to the informational context but also the underlying opinion formation. Author SummaryDistinctive neural underpinnings of opinion formation and change during in-person and online social interactions are not well understood. Here, we analyze EEG recordings of the participants interacting with a simulated social media platform and during an in-person discussion using a network-based analysis approach. We show that the structure of network reconfigurations during these interactions is diagnostic of the opinion change and the context in which information was received.

neuroscience↗

bioRxiv2020

EEG signatures of contextual influences on visual search with real scenes

The use of scene context is a powerful way by which biological organisms guide and facilitate visual search. Although many studies have shown enhancements of target-related electroencephalographic activity (EEG) with synthetic cues, there have been fewer studies demonstrating such enhancements during search with scene context and objects in real world scenes. Here, observers covertly searched for a target in images of real scenes while we used EEG to measure the steady state visual evoked response to objects flickering at different frequencies. The target appeared in its typical contextual location or out of context while we controlled for low-level properties of the image including target saliency against the background and retinal eccentricity. A pattern classifier using EEG activity at the relevant modulated frequencies showed target detection accuracy increased when the target was in a contextually appropriate location. A control condition for which observers searched the same images for a different target orthogonal to the contextual manipulation, resulted in no effects of scene context on classifier performance, confirming that image properties cannot explain the contextual modulations of neural activity. Pattern classifier decisions for individual images was also related to the aggregated observer behavioral decisions for individual images. Together, these findings demonstrate target-related neural responses are modulated by scene context during visual search with real world scenes and can be related to behavioral search decisions. Significance StatementContextual relationships among objects are fundamental for humans to find objects in real world scenes. Although there is a larger literature understanding the brain mechanisms when a target appears at a location indicated by a synthetic cue such as an arrow or box, less is known about how the scene context modulates target-related neural activity. Here we show how neural activity predictive of the presence of a searched object in cluttered real scenes increases when the target object appears at a contextual location and diminishes when it appears at a place that is out of context. The results increase our understanding of how the brain processes real scenes and how context modulates object processing.

neuroscience↗