Article
Chemistry, Multidisciplinary
Rebekka Weber, Kerby Chok, Stephan Junek, Clemens Glaubitz, Alexander Heckel
Summary: This study presents the synthesis and photophysical characterization of a two-photon sensitive uncaging dyad based on rhodamine 101 as donor fluorophore and a redshifted BODIPY as acceptor photocage. The liberation of p-nitroaniline (PNA) upon one-photon photolysis was confirmed by HPLC analysis. The considerable change of the fluorescence properties of the chromophores indicated the occurrence of the photoreaction. The possibility of fluorescent read-out enabled the detection of two-photon induced uncaging by confocal fluorescence microscopy.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Physics, Multidisciplinary
Jakob Hinney, Adarsh S. Prasad, Sahand Mahmoodian, Klemens Hammerer, Arno Rauschenbeutel, Philipp Schneeweiss, Juergen Volz, Max Schemmer
Summary: The study explores quadrature squeezing observed in a weak guided light field transmitted through an ensemble of atoms coupled to an optical nanofiber. By measuring the squeezing spectrum, direct access to the phase and amplitude of the energy-time entangled part of the two-photon wave function is obtained. The research provides a diagnostic tool for quantum optics devices by characterizing the entangled two-photon component.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Yu Wang, Mengtao Sun, Lingyan Meng
Summary: The high-order nonlinearity enables larger signal enhancements in two-photon spectroscopy compared to one-photon spectroscopy, important for conducting photoluminescence measurements at the single molecule level. Theoretical investigation on two-photon-excited fluorescence (2pF) of monolayer MoS2 in various tip-enhanced spectroscopy configurations achieved large enhancement factor on the order of 10^5 by optimizing tip parameters. Calculations of radiative and nonradiative decay rates further elucidated the 2pF emission mechanism.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Yuta Fujihashi, Akihito Ishizaki
Summary: The study explores spectroscopic measurements using entangled three photons, combining time-resolved entangled photon spectroscopy with monochromatic pumping and frequency-dispersed two-photon counting technique. The method allows for enhanced sensitivity and selectivity in measurements by suppressing undesired accidental photon counts in the detector.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Ana-Maria Craciun, Laurentiu Susu, Monica Baia
Summary: The intrinsic photoluminescence properties of gold nanorods coated with gelatin were studied using innovative fluorescence spectroscopy combined with fluorescence lifetime imaging microscopy. The study revealed interesting aspect ratio-dependent two-photon excited photoluminescence emission, with a lifetime of around 100 ps. The effect of laser excitation power and wavelength on the photoluminescence performance was evaluated, highlighting the potential application of gelatin-coated gold nanorods as contrast agents for label-free two-photon fluorescence imaging.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Environmental Sciences
Christine Loughlin, Ana R. Marques Mendes, Liam Morrison, Audrey Morley
Summary: The study analyzed the distribution of microplastics collected from the Iceland continental shelf and surrounding areas, revealing a high abundance and wide distribution range of fiber microplastics. The results suggest that the feeding and breeding grounds of Atlantic Cod may serve as significant hotspots for the accumulation of marine debris.
MARINE POLLUTION BULLETIN
(2021)
Article
Chemistry, Physical
Yizhi Zhu, Jinping Chen, Qiannan Cui, Heng Guo, Zhuxin Li, Zengliang Shi, Chunxiang Xu
Summary: A new spatiotemporal sectioning technique utilizing luminescent nanosheets has been reported, allowing for visualization of the axial evolution of TPF ellipsoid and explaining the nonlinear expansion of its axial length. The observed phenomena are attributed to photocarrier trapping and TPF photon recycling processes within the luminescent nanosheets. This technique is expected to be widely applicable and will lead to numerous investigations and applications utilizing TPF ellipsoid.
Article
Materials Science, Multidisciplinary
Ryudo Tsukizaki, Yusuke Yamashita, Kiyoshi Kinefuchi, Kazutaka Nishiyama
Summary: This study reports measurements of the xenon ground state and excited state densities inside a mu 10 microwave ion thruster, and quantitatively evaluates the mechanism behind the 40% thrust enhancement upon changing propellant injection mode. The results show that propellant flow rate and ion acceleration directly impact neutral density, with collisions of neutrals generating excited states affecting ground state emissions. propellant injection mode from the discharge chamber effectively suppresses collisions with electrons and interference with microwave propagation.
Article
Optics
Sandro Heuke, Carla Silva Martins, Remi Andre, Loic Legoff, Herve Rigneault
Summary: Two-photon excited fluorescence (2PEF) microscopy is a popular nonlinear imaging method for biomedical samples. It uses multiple detectors and spectral filter sets to discriminate different fluorophores based on their emission behavior. However, 2PEF suffers from the loss of fluorescence photons outside the filter transmission range and may fail to discriminate fluorophores with similar emission profiles. Here, we propose an alternative 2PEF method that discriminates fluorophores based on their excitation spectra.
Article
Chemistry, Multidisciplinary
Rebekka Weber, Stephan Junek, Alexander Heckel
Summary: In this study, a blue light and NIR light activatable rhodamine fluorophore was developed for biological imaging. By immobilizing the fluorophore in a hydrogel, spatially resolved illumination patterns with excellent contrast could be written and read after both one-photon and two-photon excitation.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Physics, Multidisciplinary
Eduardo Zubizarreta Casalengua, Elena del Valle, Fabrice P. Laussy
Summary: In this paper, we discuss the two-photon correlations from side peaks formed when a two-level system emitter is coherently driven with a detuning between the driving source and the emitter. We combine the theories of frequency-resolved photon correlations and homodyning to provide a neat picture compatible with perturbative two-photon scattering. This has implications for controlling, enhancing, and exploring new regimes of multiphoton emission. We also propose a way to demonstrate the quantum coherent nature of the process solely through photoluminescence observations.
Article
Chemistry, Physical
Michael G. Raymer, Tiemo Landes, Andrew H. Marcus
Summary: This article explores the theoretical and experimental studies of two-photon absorption of molecules with time-frequency-entangled photon pairs and other nonlinear interactions, focused on handling the quantum nature of light. It combines basic quantum optics theory with density matrix derivation, emphasizing the use of entangled states and the enhancement of TPA. The article also compares TPA processes occurring via different intermediate states and discusses the challenges faced in experimental studies.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Minghao Ni, Ming Gong, Xiang Li, Jinlou Gu, Bo Li, Ye Chen
Summary: Metal-organic frameworks (MOFs) are widely recognized for their excellent physical and chemical properties, with applications in optics such as fluorescent probes and solid-state light-emitting devices. This study doped TCPP into UiO-66 MOF to achieve intriguing optical performance, demonstrating good fluorescence properties and meeting expectations for nonlinear optical properties and two-photon absorption. The research opens up new possibilities for constructing MOF-based solid-state devices with diverse optical applications.
APPLIED MATERIALS TODAY
(2021)
Article
Optics
Aulide Martinez-Tapia, Samuel Corona-Aquino, Freiman Triana-Arango, Chenglong You, Rui-Bo Jin, Omar S. Magana-Loaiza, Shi-Hai Dong, Alfred B. U'Ren, Roberto de J. Leon-Montiel
Summary: Recent investigations have shown the potential of using non-classical states of light in experimental two-photon absorption spectroscopy. However, there is still a debate on whether entangled two-photon absorption has truly been observed, as single-photon-loss mechanisms may mimic this behavior. In this study, transmission measurements of entangled two-photon absorption were conducted, and it was found that the N00N-state configuration is insensitive to linear (single-photon) losses, making it a strong candidate for the certification of this phenomenon in any sample.
Article
Chemistry, Analytical
Jiangyan Wang, Jiangfeng Li, Lizhen Xu, Dan Tan, Rui Guo, Weiying Lin
Summary: Diabetes mellitus and its complications pose a significant healthcare burden worldwide, but the lack of effective biomarkers and non-invasive real-time monitoring tools remains a challenge for early diagnosis. This study introduces a two-photon probe DM-FA for selective monitoring of endogenous formaldehyde (FA) levels during diabetes mellitus. The probe exhibits excellent selectivity, high growth factor, and good photostability, and has been successfully used for visualizing FA in cells and mice. The findings provide a novel strategy for diagnosing and evaluating the efficacy of drug therapy for diabetes mellitus, with potential impact on clinical medicine.
ANALYTICA CHIMICA ACTA
(2023)
Editorial Material
Biochemistry & Molecular Biology
P. W. Barnes, T. M. Robson, P. J. Neale, C. E. Williamson, R. G. Zepp, S. Madronich, S. R. Wilson, A. L. Andrady, A. M. Heikkila, G. H. Bernhard, A. F. Bais, R. E. Neale, J. F. Bornman, M. A. K. Jansen, A. R. Klekociuk, J. Martinez-Abaigar, S. A. Robinson, Q-W Wang, A. T. Banaszak, D-P Haeder, S. Hylander, K. C. Rose, S-A Wangberg, B. Foereid, W-C Hou, R. Ossola, N. D. Paul, J. E. Ukpebor, M. P. S. Andersen, J. Longstreth, T. Schikowski, K. R. Solomon, B. Sulzberger, L. S. Bruckman, K. K. Pandey, C. C. White, L. Zhu, M. Zhu, P. J. Aucamp, J. B. Liley, R. L. McKenzie, M. Berwick, S. N. Byrne, L. M. Hollestein, R. M. Lucas, C. M. Olsen, L. E. Rhodes, S. Yazar, A. R. Young
Summary: The Environmental Effects Assessment Panel under the Montreal Protocol evaluates the environmental and health impacts of changes in the stratospheric ozone layer and UV radiation. The panel also discusses the interlinking effects between climate change and ozone depletion, and how they affect air quality, ecosystems, human health, and materials. The assessment highlights the potential impacts of extreme climate events on the biosphere and emphasizes the benefits of controlling the production of substances contributing to ozone depletion and climate change.
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
(2022)
Article
Instruments & Instrumentation
Caitlyn M. English, Zechariah B. Kitzhaber, Kazi Ragib I. Sanim, Michail Kalaitzakis, Bhanuprakash Kosaraju, James L. Pinckney, Michael E. Hodgson, Nikolaos I. Vitzilaios, Tammi L. Richardson, Michael L. Myrick
Summary: We introduce a waterproof, lightweight, low-power fluorometer that operates on a small unmanned aircraft system (sUAS) to measure chlorophyll and trigger water sampling. The fluorometer utilizes a 450 nm laser for excitation and a standard photodiode for fluorescence detection. Control and communication are achieved through an Arduino microcontroller and the robot operating system (ROS). Calibrations based on dissolved chlorophyll standards yield a detection limit of 0.2 μg per liter for a single 0.1 s measurement, decreasing with integration time. Mounting the fluorometer on the sUAS increases detection limits due to electrical noise.
APPLIED SPECTROSCOPY
(2023)
Article
Instruments & Instrumentation
Zechariah B. Kitzhaber, Caitlyn M. English, Kazi Ragib Sanim, Michail Kalaitzakis, Bhanuprakash Kosaraju, Michael E. Hodgson, Nikolaos Vitzilaios, Tammi L. Richardson, Michael L. Myrick
Summary: We describe the control and interfacing of a fluorometer designed for aerial drone-based measurements of chlorophyll-a using an Arduino Nano 33 BLE Sense board. The fluorometer was integrated into a small Uncrewed Aircraft System (sUAS) for automated water sampling through a Raspberry Pi master computer using the ROS.
APPLIED SPECTROSCOPY
(2023)
Article
Environmental Sciences
Nicholas J. Hawco, Alessandro Tagliabue, Benjamin S. Twining
Summary: A new global biogeochemical model has revealed that manganese deficiency limits the maximal growth rates of over half of the phytoplankton in the Southern Ocean. Manganese limitation is most extensive during the austral spring and is influenced by phytoplankton traits and the inhibition of manganese uptake by high zinc concentrations in the Antarctic waters. The expanded range of manganese limitation under increased iron supply during past glacial periods reduces the response of the biological carbon pump.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Marine & Freshwater Biology
Tammi L. Richardson
Summary: This review provides an overview of the origin, structure and function of cryptophyte PBPs and highlights their remarkable phenotypic plasticity, which allows cryptophytes to adapt to environmental changes.
JOURNAL OF PLANKTON RESEARCH
(2022)
Article
Nanoscience & Nanotechnology
Peyman Babakhani, Tanapon Phenrat, Mohammed Baalousha, Kullapa Soratana, Caroline L. Peacock, Benjamin S. Twining, Michael F. Hochella
Summary: This analysis examines the potential benefits and challenges of using engineered nanoparticles for carbon sequestration through artificial ocean fertilization. The study shows that some nanoparticles can enhance phytoplankton growth, increase carbon export, and address limitations in artificial ocean fertilization. Although it comes with higher costs, this technology could be an important component in mitigating global warming.
NATURE NANOTECHNOLOGY
(2022)
Article
Instruments & Instrumentation
Caitlyn M. English, Zechariah B. Kitzhaber, Kazi Ragib I. Sanim, Nikolaos Vitzilaios, Michael E. Hodgson, Tammi L. Richardson, Michael L. Myrick
Summary: We have developed a lightweight, low-power, waterproof filter fluorometer for chlorophyll-a detection. Through modeling and calibration, we determined the calibration slope and detection limit for dissolved chl-a in water. The experimental results validate our model, showing good agreement with the estimated values. The achieved detection limit is suitable for practical applications.
APPLIED SPECTROSCOPY
(2023)
Article
Geosciences, Multidisciplinary
P. N. Sedwick, B. M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, T. E. Williams
Summary: Constraining the role of dust deposition in regulating the concentration of iron in surface ocean waters requires understanding the flux of seawater-soluble iron in aerosols and the replacement time of dissolved iron in the euphotic zone. This study estimates these quantities using DFe data from the Bermuda Atlantic Time-series Study region and measurements of iron in aerosols and rain from Bermuda in 2019. The results suggest a seasonal variation in surface DFe concentrations and a mean euphotic-zone residence time of 0.8-1.9 years for DFe with respect to aeolian input.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
N. A. Wiseman, J. K. Moore, B. S. Twining, D. S. Hamilton, N. M. Mahowald
Summary: Dissolved iron (dFe) is crucial for regulating marine productivity. Its availability affects carbon export and nitrogen fixation, and is dependent on phytoplankton iron quotas. Adding dynamic, group-specific, phytoplankton Fe:C ratios to ocean models improves representation of observed trends and helps understand biogeochemical responses to varying iron cycling and atmospheric deposition.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Computer Science, Artificial Intelligence
Kazi Ragib Ishraq Sanim, Caitlyn English, Zechariah B. Kitzhaber, Michail Kalaitzakis, Nikolaos Vitzilaios, Michael L. Myrick, Michael E. Hodgson, Tammi L. Richardson
Summary: This paper introduces a novel autonomous UAS capable of sensing water properties and collecting water samples. The system features a customized UAS with a fluorescence sensor and pumping mechanism. The system does in situ fluorescence measurements to determine the best sampling spot. To ensure safe operation, sensor fusion with an Extended Kalman Filter has been implemented. Experimental results from two different water ecosystems are presented to validate the system's performance.
JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS
(2023)
Article
Biochemistry & Molecular Biology
A. L. Andrady, A. M. Heikkilae, K. K. Pandey, L. S. Bruckman, C. C. White, M. Zhu, L. Zhu
Summary: The harmful effects of solar UV radiation on construction materials and the resulting impact on their lifetimes are well documented. Climate change will further shorten the lifetimes of materials, requiring higher levels of stabilisation. The Montreal Protocol controls the solar UV-B radiation received on Earth. This assessment provides an update on the effects of UV radiation on materials and discusses emerging technologies for better stabilising them.
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
(2023)
Article
Remote Sensing
Michael E. Hodgson, Nikolaos Vitzilaios, Michael L. Myrick, Tammi L. Richardson, Matt Duggan, Kazi Ragib Sanim, Michail Kalaitzakis, Bhanuprakash Kosaraju, Caitlyn English, Zechariah Kitzhaber
Summary: Mission planning for small uncrewed aerial systems as a platform for remote sensors is more complex than traditional issues, considering various environmental changes and regulatory requirements. This research designed a visibility model for low-altitude aerial drone operations using a GIS-based framework and high spatial resolution LiDAR data, demonstrating its utility and challenges through a water sampling case study in South Carolina.
Article
Biochemistry & Molecular Biology
Benjamin S. Twining, Stephen B. Baines
Summary: This study quantified the cellular trafficking of iron in a globally relevant phytoplankton group and found that iron was stored in storage bodies adjacent to chloroplasts in iron-limited areas. The stored iron was then distributed to the rest of the cell through subsequent growth and division.
Review
Energy & Fuels
G. Oreski, J. S. Stein, G. C. Eder, K. Berger, L. Bruckman, R. French, J. Vedde, K. A. Weiss
Summary: Photovoltaic module manufacturers have faced cost pressures, leading to the development of new module designs and material innovations. However, the lack of long-term understanding of the performance and reliability of these new materials has resulted in unexpected failure modes. Therefore, new accelerated test approaches are needed to assess the performance and reliability of these new materials and designs.
PROGRESS IN ENERGY
(2022)
