A5054881446- Per- and polyfluoroalkyl substances research
- Toxic Organic Pollutants Impact
- Molecular Junctions and Nanostructures
- Air Quality and Health Impacts
- Effects and risks of endocrine disrupting chemicals
- Electrochemical Analysis and Applications
- Quantum and electron transport phenomena
- Atmospheric chemistry and aerosols
- Photochemistry and Electron Transfer Studies
- Organic Electronics and Photovoltaics
- Skin Protection and Aging
- Lysosomal Storage Disorders Research
- Environmental Justice and Health Disparities
- Spectroscopy and Quantum Chemical Studies
- Force Microscopy Techniques and Applications
- Nanowire Synthesis and Applications
- Indoor Air Quality and Microbial Exposure
- Quantum Electrodynamics and Casimir Effect
- Plasmonic and Surface Plasmon Research
- Bacterial Genetics and Biotechnology
- Occupational exposure and asthma
- Chemistry and Chemical Engineering
- Animal testing and alternatives
- Electrochemical sensors and biosensors
- Quantum-Dot Cellular Automata
Media Working Group
2011-2025
Historic England
2019
Northwestern University
2006-2009
University of East Anglia
2008
Dalhousie University
2007
Wesleyan University
2005
National Institute of Mental Health
2001-2002
National Institutes of Health
2001-2002
Drinking water contamination with poly- and perfluoroalkyl substances (PFASs) poses risks to the developmental, immune, metabolic, endocrine health of consumers. We present a spatial analysis 2013–2015 national drinking PFAS concentrations from U.S. Environmental Protection Agency's (US EPA) third Unregulated Contaminant Monitoring Rule (UCMR3) program. The number industrial sites that manufacture or use these compounds, military fire training areas, wastewater treatment plants are all...
Per- and polyfluoroalkyl substances (PFASs) are highly persistent synthetic chemicals, some of which have been associated with cancer, developmental toxicity, immunotoxicity, other health effects. PFASs in grease-resistant food packaging can leach into increase dietary exposure. We collected ∼400 samples contact papers, paperboard containers, beverage containers from fast restaurants throughout the United States measured total fluorine using particle-induced γ-ray emission (PIGE)...
This commentary presents a scientific basis for managing as one chemical class the thousands of chemicals known PFAS (per- and polyfluoroalkyl substances). The includes perfluoroalkyl acids, perfluoroalkylether their precursors; fluoropolymers perfluoropolyethers; other PFAS. approach is presented in relation to physicochemical, environmental, toxicological properties. Specifically, high persistence, accumulation potential, and/or hazards (known potential) studied date warrant treating all...
The Florence Statement on Triclosan and Triclocarban documents a consensus of more than 200 scientists medical professionals the hazards lack demonstrated benefit from common uses triclosan triclocarban. These chemicals may be used in thousands personal care consumer products as well building materials. Based extensive peer-reviewed research, this statement concludes that triclocarban are environmentally persistent endocrine disruptors bioaccumulate toxic to aquatic other organisms. Evidence...
The extent of ongoing exposure to the general public from per- and polyfluoroalkyl substances (PFAS) in drinking water United States worldwide remains uncertain. Here, we analyze publicly accessible data sets PFAS occurrence States. Testing with detection limits below 1 ng/L revealed that mixtures are nearly ubiquitous surface water, predominate source for U.S. population. We estimate 18–80 million people receive tap 10 or greater concentration perfluorooctanoic acid (PFOA)...
Per- and polyfluoroalkyl substances, or PFAS, gained significant public regulatory attention due to widespread contamination health harms associated with exposure. Ingestion of PFAS from contaminated food water results in the accumulation body is considered a key route human Here we calculate potential contribution PFOS consumption locally caught freshwater fish serum levels. We analyzed data for over 500 composite samples fillets collected across United States 2013 2015 under U.S. EPA's...
Environmental contamination by fluorinated chemicals, in particular chemicals from the per- and polyfluoroalkyl substances (PFAS) class, has raised concerns around globe because of documented adverse impacts on human health, wildlife, ecosystem quality. Recent studies have indicated that pesticide products may contain a variety meet PFAS definition, including active ingredients themselves. Given pesticides are some most widely distributed pollutants across world, legacy addition into could...
Theory and experiment examining electron transfer through molecules bound to electrodes are increasingly focused on quantities that conceptually far removed from current chemical understanding. This presents challenges both for the design of interesting these devices interpretation experimental data by traditional mechanisms. Here, concept electronic coupling theories intramolecular is extended applied in scattering theory (Landauer) formalism. yields a simple sum over independent channels,...
We calculate that significant quantum interference effects can be observed in elastic electron transport through acyclic molecules. Interference features are evident the transmission characteristics calculated for cross-conjugated molecules; significantly, these dominate experimentally observable conduction range. The unusual of molecules highlighted comparison with linearly conjugated and nonconjugated systems. presented here show a large dynamic range conductance. These findings represent...
Schnyder crystalline corneal dystrophy (SCCD, MIM 121800) is a rare autosomal dominant disease characterized by progressive opacification of the cornea resulting from local accumulation lipids, and associated in some cases with systemic dyslipidemia. Although previous studies genetics SCCD have localized defective gene to 1.58 Mbp interval on chromosome 1p, exhaustive sequencing positional candidate genes has thus far failed reveal causal mutations. We ascertained large multigenerational...
Molecular electronics is partly driven by the goal of producing active electronic elements that rival performance their solid-state counterparts, but on a much smaller size scale. We investigate what constitutes an ideal switch or molecular device, and how it can be designed, analyzing transmission plots. The interference features in cross-conjugated molecules provide large dynamic range electron probability, opening new area for addressing functionality molecules. This accessible through...
The mechanism for off-resonant electron transport through small organic molecules in metallic junctions is predominantly coherent tunneling. Thus, new device functionalities based on quantum interference could be developed the field of molecular electronics. We invoke a partitioning technique to give an analytical treatment benzene ring. interpret antiresonances transmission as either multipath zeroes resulting from interfering spatial pathways or resonance analogous induced by sidechains.
We present an interesting consequence of the differences between cross-conjugated and linearly conjugated molecules: breakdown conventional understanding trends in molecular electron transfer. Interference effects are dominant molecules with unusual results: long may have faster rates transfer than short molecules, saturated same length, rate cannot be correlated energy gaps donor acceptor states levels bridging molecule.
In molecular transport junctions, current is monitored as a function of the applied voltage for single molecule assembled between two leads. The modulated by electronic states molecule. For prototypical delocalized systems, namely, pi-conjugated aromatics, pi system usually dominates transport. Herein, we investigate situations where model calculations including only do not capture all subtleties properties. Including both sigma and contributions to charge allows us demonstrate that while...
A wide-field localized surface plasmon resonance (LSPR) imaging method using a liquid crystal tunable filter (LCTF) is used to measure the scattering spectra of multiple Ag nanoparticles in parallel. This provides ability characterize moving by measuring particles while simultaneously tracking their motion. Consequently, single particle diffusion coefficients can be determined. As an example, several nanoprisms are tracked, LSPR spectrum each obtained, and coefficient determined from its...
The experimental variation in conductance that can be expected through dynamically evolving Au−molecule−Au junctions is approximated using molecular dynamics to model thermal fluctuations and a nonequilibrium Green's function code (Hückel-IV 2.0) calculate the charge transport. This generates statistical set of data used compare directly with results. Experimental measurements on Au−single molecule show large values between different identically prepared junctions. Our computational results...
We report on a class of molecules that exhibit nonlinear current/voltage behavior in the low bias tunneling regime. This interesting is attributed to quantum interference. Using site models, we show interference features, while common, do not necessarily occur at experimentally relevant energies, hindering realization transport measurements. Calculations made using nonequilibrium Green's function code can be cross-conjugated molecules. A detailed bond length analysis gives insight into why...
Abstract Drinking water contamination with per‐ and polyfluoroalkyl substances (PFAS) poses a health risk for communities across the country. The vast majority of systems United States lack both technology funds to filter out PFAS. Release PFAS industrial wastewater from variety facilities is significant contributor drinking water. Here, we provide screening‐level analysis potential environmental releases contaminated sites, active treatment plants, waste disposal sites (including inactive...
A p-benzenedithiolate (BDT) molecule covalently bonded between two gold electrodes has become one of the model systems utilized for investigating molecular transport junctions. The plethora papers published on BDT system led to varying conclusions with respect both mechanism and magnitude transport. Conductance variations have been attributed difficulty in calculating charge transfer molecule, inability locate Fermi energy accurately, geometric dispersion, stochastic switching. Here we...
The development of high-throughput screening methodologies may decrease the need for laboratory animals toxicity testing. Here, we investigate potential assessing immunotoxicity with data from U.S. Environmental Protection Agency ToxCast program. As case studies, analyzed most common chemicals added to food as well per- and polyfluoroalkyl substances (PFAS) shown migrate packaging materials or processing equipment. antioxidant preservative tert-butylhydroquinone (TBHQ) showed activity both...
Exposure to cleaning products has been associated with harm the respiratory system, neurotoxicity, reproductive and elevated risk of cancer, greatest adverse impacts for workers exposed in an occupational setting. Social consumer interest that are safer health created a market category "green" defined here as advertised healthier, non-toxic, or free from harmful chemicals well third-party certification safety environmental features. In present study we examined air quality fresheners,...