A5079181375- Photonic and Optical Devices
- Photonic Crystals and Applications
- Optical Coatings and Gratings
- Evolution and Genetic Dynamics
- Fern and Epiphyte Biology
- Evolutionary Game Theory and Cooperation
- Gut microbiota and health
- Plasmonic and Surface Plasmon Research
- Mycotoxins in Agriculture and Food
- Microbial Community Ecology and Physiology
- Mechanical and Optical Resonators
- Microbial Metabolic Engineering and Bioproduction
- Optical Network Technologies
- Enzyme-mediated dye degradation
- Plant and fungal interactions
- Plant and animal studies
- Advanced Fiber Laser Technologies
- Ecosystem dynamics and resilience
- Fungal and yeast genetics research
- Advanced Fiber Optic Sensors
- Gene Regulatory Network Analysis
- Insect and Arachnid Ecology and Behavior
- Plant-Microbe Interactions and Immunity
- Slime Mold and Myxomycetes Research
- SARS-CoV-2 and COVID-19 Research
Boston College
2016-2025
Boston University
2023
Chestnut Hill College
2021
Fred Hutch Cancer Center
2010-2017
Cancer Research Center
2012-2017
Cape Town HVTN Immunology Laboratory / Hutchinson Centre Research Institute of South Africa
2012-2017
Georgia Institute of Technology
2003-2011
Sharif University of Technology
2004
Pairwise models are commonly used to describe many-species communities. In these models, an individual receives additive fitness effects from pairwise interactions with each species in the community ('additivity assumption'). All typically represented by a single equation where parameters reflect signs and strengths of ('universality Here, we show that fails qualitatively capture diverse microbial interactions. We build mechanistic reference for two engaging commonly-found chemical-mediated...
Patterns of spatial positioning individuals within microbial communities are often critical to community function. However, understanding patterning in natural is hampered by the multitude cell–cell and cell–environment interactions as well environmental variability. Here, through simulations experiments on defined environments, we examined how ecological between two distinct partners impacted patterning. We found that strong cooperation with spatially localized large fitness benefits both...
Heterotypic cooperation—two populations exchanging distinct benefits that are costly to produce—is widespread. Cheaters, exploiting while evading contribution, can undermine cooperation. Two mechanisms stabilize heterotypic In ‘partner choice’, cooperators recognize and choose cooperating over cheating partners; in fidelity feedback’, fitness-feedback from repeated interactions ensures aiding your partner helps yourself. How might a spatial environment, which facilitates interactions,...
We experimentally demonstrate a high resolution integrated spectrometer on silicon insulator (SOI) substrate using large-scale array of microdonut resonators. Through top-view imaging and processing, the measured spectral response shows linewidth ~0.6 nm with an operating bandwidth ~50 nm. This is achieved in compact size miniaturized resonators (radius ~2 μm) quality factor, single-mode operation, large free range. The microspectrometer realized process compatible fabrication has great...
Many microbial functions happen within communities of interacting species. Explaining how species with disparate growth rates can coexist is important for applications such as manipulating host-associated microbiota or engineering industrial communities. Here, we ask microbes through their chemical environment achieve coexistence in a continuous setup (similar to an bioreactor gut microbiota) where external resources are being supplied. We formulate and experimentally constrain model which...
In human microbiota, the prevention or promotion of invasions can be crucial to health. Invasion outcomes, in turn, are impacted by composition resident communities and interactions members with invader. Here we study how influence invasion outcomes microbial communities, when primarily mediated chemicals that released into consumed from environment. We use a previously developed dynamic model which explicitly includes species abundances concentrations mediate interaction. Using this model,...
Here, we demonstrate a compact photonic crystal wavelength demultiplexing device based on diffraction compensation scheme with two orders of magnitude performance improvement over the conventional superprism structures reported to date.We show that main problems superprism-based devices can be overcome by combining effect other properties crystals, i.e., negative and refraction.Here, 4-channel optical demultiplexer channel spacing 8 nm cross-talk level better than -6.5 dB is experimentally...
Quantitative modeling is useful for predicting behaviors of a system and rationally constructing or modifying the system. The predictive power model relies on accurate quantification parameters. Here, we illustrate challenges in parameter offer means to overcome these challenges, using case example which quantitatively predict growth rate cooperative community. Specifically, community consists two Saccharomyces cerevisiae strains, each engineered release metabolite required consumed by its...
We investigate laccase-mediated detoxification of aflatoxins, fungal carcinogenic food contaminants. Our experimental comparison between two aflatoxins with similar structures (AFB1 and AFG2) shows significant differences in detoxification. A multi-scale modeling approach (Docking, Molecular Dynamics, Density Functional Theory) identifies the highly substrate-specific changes required to improve laccase detoxifying performance. employ a large-scale density functional theory-based approach,...
Aflatoxins (AFs) are fungal metabolites that ubiquitously contaminate many common food crops and contribute to major foodborne diseases in humans animals. Known chemical strategies have used strong acids bases remove contaminating AF, but these methods often lead undesired ecological waste issues downstream. In this study, the application of weaker acidic alkaline conditions removes two types AFs, AFB 1 AFG 2 , is investigated. The results showed an environment buffered at a pH 9 reduced by...
We demonstrate the feasibility of forming a compact integrated photonic spectrometer for operation in visible wavelength range using dispersive properties planar crystal structure fabricated silicon nitride.High resolution and device sizes these spectrometers are enabled by combining superprism effect, negative diffraction refraction effect 45° rotated square lattice crystal.Our experimental demonstration shows 1.2 nm 70 µm 130 with better performance than alternative structures on-chip...
Abstract The role of aflatoxins (AFs) in the biology producing strains, Aspergillus sect. Flavi, is still a matter debate. Over recent years, research has pointed to how environmental factors altering redox balance fungal cell can switch on synthesis AF. Notably, it been known for decades that oxidants promote AF synthesis. More evidence indicated controlled at transcriptional level: reactive species accumulate cells stationary growth phase modulate expression aflR, main regulator...
To alter microbial community composition for therapeutic purposes, an accurate and reliable modeling framework capable of predicting outcomes is required. Lotka-Volterra (LV) equations have been utilized to describe a breadth communities, yet, the conditions in which this successful remain unclear. Here, we propose that set simple vitro experiments-growing each member cell-free spent medium obtained from other members-can be used as test decide whether LV model appropriate describing...
A two-dimensional (2-D) finite-difference time-domain (FDTD) code for the study of nonlinear optical phenomena, in which both slowly varying and rapidly components electromagnetic fields are considered, has been developed. The algorithm solves vectorial Maxwell's equations all field uses constitutive relation matrix form as required to describe system. stability is discussed its effectiveness demonstrated through simulations self-phase modulation (SPM) second-harmonic generation (SHG)....
In this letter, we present a matching stage for reflection reduction based on the principle of gradual change to efficiently couple light propagating modes photonic crystals (PCs). Basic physical considerations in designing these stages are investigated and systematic yet simple design procedure is suggested. We show that obtained using method wideband frequency, have wide acceptance angle, robust against fabrication imperfections. Therefore, they preferred choice general-purpose be used...
We present a method for eliminating the temperature dependence of resonance wavelength in high-Q silicon-based microdisk resonators by using polymer cladding with negative thermo-optic coefficient. Design requirements athermal performance are derived based on theory and simulation, their validity is experimentally verified.