Search Our Scientific Publications & Authors

J Insect Sci 2021 Mar;21(2)

School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL, UK.

We describe the development, field testing, and results from an automated 3D insect flight detection and tracking system for honey bees (Apis mellifera L.) (Hymenoptera: Apidae) that is capable of providing remarkable insights into airborne behavior. It comprises two orthogonally mounted video cameras with an observing volume of over 200 m3 and an offline analysis software system that outputs 3D space trajectories and inflight statistics of the target honey bees. Read More

Phys Rev Lett 2021 Apr;126(13):135101

Harvard University, Cambridge, Massachusetts 02138, USA.

The first self-consistent simulations of electron acceleration during magnetic reconnection in a macroscale system are presented. Consistent with solar flare observations, the spectra of energetic electrons take the form of power laws that extend more than two decades in energy. The drive mechanism for these nonthermal electrons is Fermi reflection in growing and merging magnetic flux ropes. Read More

Phys Rev Lett 2021 Apr;126(13):131103

Institut für Geophysik, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland.

We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32. Read More

Nat Commun 2021 04 15;12(1):2262. Epub 2021 Apr 15.

Hydrological Sciences Laboratory, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD, USA.

El Nino is a critical part of global inter-annual climate variability, and the intensity of El Nino has major implications for rainfall-induced natural hazards in many vulnerable countries. The impact of landslides triggered by rainfall is likely to be modulated by the strength of El Nino, but the nature of this connection and the places where it is most relevant remains unconstrained. Here we combine new satellite rainfall data with a global landslide exposure model to show that El Nino has far-reaching effects on landslide impacts to people and infrastructure. Read More

Nat Commun 2021 04 15;12(1):2266. Epub 2021 Apr 15.

Department of Biology, San Diego State University, San Diego, CA, USA.

Wetland methane (CH) emissions ([Formula: see text]) are important in global carbon budgets and climate change assessments. Currently, [Formula: see text] projections rely on prescribed static temperature sensitivity that varies among biogeochemical models. Meta-analyses have proposed a consistent [Formula: see text] temperature dependence across spatial scales for use in models; however, site-level studies demonstrate that [Formula: see text] are often controlled by factors beyond temperature. Read More

Sci Rep 2021 Apr 14;11(1):8151. Epub 2021 Apr 14.

Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, Durban, 4041, South Africa.

Two Schiff bases, (E)-1-(4-methoxyphenyl)-N-((E)-3-(4-nitrophenyl)allylidene)methanamine (compound 1) and (E)-N-((E)-3-(4-nitrophenyl)allylidene)-2-phenylethanamine (compound 2) have been synthesized and characterized using spectroscopic methods; time of flight MS, H and C NMR, FT-IR, UV-VIS, photoluminescence and crystallographic methods. The structural and electronic properties of compounds 1 and 2 in the ground state were also examined using the DFT/B3LYP functional and 6-31 + G(d,p) basis set, while the electronic transitions for excited state calculations were carried out using the TD-DFT/6-31 + G(d,p) method. The Schiff base compounds, 1 and 2 crystallized in a monoclinic crystal system and the P2/c space group. Read More

PLoS One 2021 14;16(4):e0249680. Epub 2021 Apr 14.

Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.

With an increasing number of unmanned aerial vehicles (UAVs), the difficulty of UAV management becomes more challenging, especially for low-altitude airspace due to complicated issues of security, privacy and flexibility. Existing management approaches to UAV flights include implementing registration of flight activity for supervision purposes, limiting the maximum flight height, setting different zones for different flight activities and prohibiting flights. In this research, we proposed a new air traffic management method for UAVs based on global subdivision theory. Read More

NPJ Microgravity 2020 Oct 8;6(1):30. Epub 2020 Oct 8.

KBR, Houston, TX, USA.

A subset of long-duration spaceflight astronauts have experienced ophthalmic abnormalities, collectively termed spaceflight-associated neuro-ocular syndrome (SANS). Little is understood about the pathophysiology of SANS; however, microgravity-induced alterations in intracranial pressure (ICP) due to headward fluid shifts is the primary hypothesized contributor. In particular, potential changes in optic nerve (ON) tortuosity and ON sheath (ONS) distension may indicate altered cerebrospinal fluid dynamics during weightlessness. Read More

J Chromatogr A 2021 Mar 26;1645:462101. Epub 2021 Mar 26.

Soremartec Italia srl, Alba, Cuneo Italy.

Accurate, reliable, and informative mapping of untargeted and targeted components across many samples is here performed by combining off-line GC-Olfactometry (GC-O) and comprehensive two-dimensional gas chromatography (GC×GC) coupled to time-of-flight mass spectrometry with variable ionization energy (TOF MS featuring Tandem Ionization™). In particular, untargeted and targeted (UT) features patterns are processed by chromatographic fingerprinting, giving differential priority to potent odorants' retention-times regions. Distinguishing peppermint essential oil (EO) from Piedmont (Italy - Mentha × piperita L. Read More

Sci Rep 2021 Apr 12;11(1):7919. Epub 2021 Apr 12.

Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA.

Trees outside forests (TOF) are an underrepresented resource in forest poor nations. As a result of their frequent omission from national forest resource assessments and a lack of readily available very-high-resolution remotely sensed imagery, TOF status and characterization has until now, been unknown. Here, we assess the capacity of openly available 10 m ESA Sentinel constellation satellite imagery for mapping TOF extent at the national level in Bangladesh. Read More

Nat Commun 2021 04 12;12(1):2179. Epub 2021 Apr 12.

Department of Bioengineering, University of California, Los Angeles, CA, USA.

Cameras with extreme speeds are enabling technologies in both fundamental and applied sciences. However, existing ultrafast cameras are incapable of coping with extended three-dimensional scenes and fall short for non-line-of-sight imaging, which requires a long sequence of time-resolved two-dimensional data. Current non-line-of-sight imagers, therefore, need to perform extensive scanning in the spatial and/or temporal dimension, restricting their use in imaging only static or slowly moving objects. Read More

ACS Earth Space Chem 2021 Mar 24;5(3):436-448. Epub 2021 Feb 24.

Department of Chemistry, University of Helsinki, P.O. Box 55, A. I. Virtasen aukio 1, FI-00014 Helsinki, Finland.

X-ray astronomy lacks high resolution spectra of interstellar dust analogues and molecules, severely hampering interstellar medium studies based on upcoming X-ray missions. Various theoretical approaches may be used to address this problem, but they must first be shown to reproduce reliable spectra compared to the experiment. In this work, we calculate the sulfur K edge X-ray absorption spectra of HS, SO, and OCS, whose spectra are already known from X-ray experiments and predict the X-ray spectrum of CS, which as far as we are aware has not been measured, thereby hampering its detection by X-ray telescopes. Read More

Front Neurol 2021 26;12:648958. Epub 2021 Mar 26.

Departments of Ophthalmology, Stanford University, Palo Alto, CA, United States.

Astronauts who undergo prolonged periods of spaceflight may develop a unique constellation of neuro-ocular findings termed Spaceflight Associated Neuro-Ocular Syndrome (SANS). SANS is a disorder that is unique to spaceflight and has no terrestrial equivalent. The prevalence of SANS increases with increasing spaceflight duration and although there have been residual, structural, ocular changes noted, no irreversible or permanent visual loss has occurred after SANS, with the longest spaceflight to date being 14 months. Read More

Science 2021 04;372(6538):187-190

Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara 252-5258, Japan.

Giant radio pulses (GRPs) are sporadic bursts emitted by some pulsars that last a few microseconds and are hundreds to thousands of times brighter than regular pulses from these sources. The only GRP-associated emission outside of radio wavelengths is from the Crab Pulsar, where optical emission is enhanced by a few percentage points during GRPs. We observed the Crab Pulsar simultaneously at x-ray and radio wavelengths, finding enhancement of the x-ray emission by 3. Read More

Rev Sci Instrum 2021 Mar;92(3):033001

Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany.

The combination of circular dichroism with laser mass spectrometry via the measurement of ion yields is a powerful tool in chiral recognition, but the measured anisotropies are generally weak. The method presented in this contribution reduces the measurement error significantly. A common path optical setup generates a pair of counter-rotating laser foci in the interaction region of a time-of-flight spectrometer. Read More

Rev Sci Instrum 2021 Mar;92(3):033101

Natural History Museum, Burgring 7, 1010 Vienna, Austria.

This article describes a novel high frame rate emission spectroscopy setup developed for measurements in high enthalpy flow fields. The optical setup and the associated hardware arrangements are described in detail followed by test case data to demonstrate the capability of recording spectral images at 1 kHz frame rate. The new system is based on a classical Czerny-Turner spectrograph but with a particular setup for high frame rate detection using a Generation II intensifier coupled with a high-speed camera. Read More

Rev Sci Instrum 2021 Mar;92(3):035111

NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, Maryland 20771, USA.

Measuring the faint polarization signal of the cosmic microwave background (CMB) not only requires high optical throughput and instrument sensitivity but also control over systematic effects. Polarimetric cameras or receivers used in this setting often employ dielectric vacuum windows, filters, or lenses to appropriately prepare light for detection by cooled sensor arrays. These elements in the optical chain are typically designed to minimize reflective losses and hence improve sensitivity while minimizing potential imaging artifacts such as glint and ghosting. Read More

Biochem Biophys Res Commun 2021 Apr 2;555:175-181. Epub 2021 Apr 2.

The Key Laboratory of Aerospace Medicine, Ministry of Education, Air Force Medical University, 710032, Xi'an, Shaanxi, China. Electronic address:

Microgravity and radiation exposure-induced bone damage is one of the most significant alterations in astronauts after long-term spaceflight. However, the underlying mechanism is still largely unknown. Recent ground-based simulation studies have suggested that this impairment is likely mediated by increased production of reactive oxygen species (ROS) during spaceflight. Read More

Ann Glob Health 2021 Mar 26;87(1):30. Epub 2021 Mar 26.

Albert Einstein College of Medicine, Bronx, NY, USA.

Background: Multidisciplinary and multisectoral approaches such as One Health and related concepts (e.g., Planetary Health, EcoHealth) offer opportunities for synergistic expertise to address complex health threats. Read More

J Geophys Res Atmos 2021 Feb 17;126(4):e2020JD033586. Epub 2021 Feb 17.

Joint Institute for Regional Earth System Science and Engineering and Department of Atmospheric and Oceanic Sciences University of California Los Angeles CA USA.

This study examines the modifications of air-sea coupling processes by dust-radiation-cloud interactions over the North Atlantic Ocean using a high-resolution coupled atmosphere-wave-ocean-dust (AWOD) regional model. The dust-induced mechanisms that are responsible for changes of sea surface temperature (SST) and latent and sensible heat fluxes (LHF/SHF) are also examined. Two 3-month numerical experiments are conducted, and they differ only in the activation and deactivation of dust-radiation-cloud interactions. Read More

Remote Sens Environ 2020 Dec 8;251:112055. Epub 2020 Sep 8.

Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20742, USA.

Land surface temperature (LST) is a key diagnostic indicator of agricultural water use and crop stress. LST data retrieved from thermal infrared (TIR) band imagery, however, tend to have a coarser spatial resolution (e.g. Read More

Sci Total Environ 2021 Mar 22;781:146644. Epub 2021 Mar 22.

Space Enabled Research Group, Massachusetts Institute of Technology, Cambridge, MA, United States.

Gold mining has played a significant role in Ghana's economy for centuries. Regulation of this industry has varied over time and while industrial mining is prevalent in the country, the expansion of artisanal mining, or Galamsey has escalated in recent years. Many of these artisanal mines are not only harmful to human health due to the use of Mercury (Hg) in the amalgamation process, but also leave a significant footprint on terrestrial ecosystems, degrading and destroying forested ecosystems in the region. Read More

Life (Basel) 2021 Mar 27;11(4). Epub 2021 Mar 27.

Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA.

This report was designed to compare spaceflight-induced cellular and physiological adaptations of cultured in microgravity on the International Space Station across several payloads. is a common opportunistic fungal pathogen responsible for a variety of superficial infections as well as systemic and more severe infections in humans. Cumulatively, the propensity of this organism to be widespread through the population, the ability to produce disease in immunocompromised individuals, and the tendency to respond to environmental stress with characteristics associated with increased virulence, require a better understanding of the yeast response to microgravity for spaceflight crew safety. Read More

Entropy (Basel) 2021 Mar 7;23(3). Epub 2021 Mar 7.

Department of Applied Science and Technology, Politecnico di Torino, 10129 Torino, Italy.

In this paper, we consider the space-time of a charged mass endowed with an angular momentum. The geometry is described by the exact Kerr-Newman solution of the Einstein equations. The peculiar symmetry, though exact, is usually described in terms of the gravito-magnetic field originated by the angular momentum of the source. Read More

Earth Space Sci 2020 Aug 2;7(8):e2020EA001238. Epub 2020 Aug 2.

Integrated Spaceflight Services, Boulder, CO, USA.

The Polar Mesospheric Cloud Turbulence (PMC Turbo) instrument consists of a balloon-borne platform which hosts seven cameras and a Rayleigh lidar. During a 6-day flight in July 2018, the cameras captured images of Polar Mesospheric Clouds (PMCs) with a sensitivity to spatial scales from ~20 m to 100 km at a ~2-s cadence and a full field of view (FOV) of hundreds of kilometers. We developed software optimized for imaging of PMCs, controlling multiple independent cameras, compressing and storing images, and for choosing telemetry communication channels. Read More

J Geophys Res Space Phys 2020 Dec 1;126(2). Epub 2021 Feb 1.

Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA.

Longitudinal structures in the Martian thermosphere and topside ionosphere between 150 and 200 km altitudes are studied using in situ electron and neutral measurements from the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Four time intervals are selected for comparison, during which MAVEN sampled similar local time (9.3-10. Read More

J Geophys Res Atmos 2021 Feb 19;126(4):e2020JD033923. Epub 2021 Feb 19.

NASA Goddard Space Flight Center Greenbelt MD USA.

The radiative effect on microphysics (REM) plays an important role in the dew/frost formation near the surface. How REM impacts cirrus clouds is investigated in this study, using bin microphysical model simulations and coincident data of the CloudSat and Global Precipitation Measurement (GPM) satellites. REM affects ice crystal spectrum with two types: radiative cooling and warming. Read More

Geophys Res Lett 2021 Mar 26;48(5):e2020GL091987. Epub 2021 Feb 26.

Cooperative Institute for Research in Environmental Sciences (CIRES) University of Colorado Boulder CO USA.

Throughout spring and summer 2020, ozone stations in the northern extratropics recorded unusually low ozone in the free troposphere. From April to August, and from 1 to 8 kilometers altitude, ozone was on average 7% (≈4 nmol/mol) below the 2000-2020 climatological mean. Such low ozone, over several months, and at so many stations, has not been observed in any previous year since at least 2000. Read More

J Geophys Res Space Phys 2021 Mar 9;126(3):e2020JA028816. Epub 2021 Mar 9.

Astrophysics Department Argelander Institut für Astronomie University of Bonn Bonn Germany.

The LEXI and SMILE missions will provide soft X-ray images of the Earth's magnetosheath and cusps after their anticipated launch in 2023 and 2024, respectively. The IBEX mission showed the potential of an Energetic Neutral Atom (ENA) instrument to image dayside magnetosheath and cusps, albeit over the long hours required to raster an image with a single pixel imager. Thus, it is timely to discuss the two imaging techniques and relevant science topics. Read More

Geophys Res Lett 2021 Feb 23;48(4):e2020GL091125. Epub 2021 Feb 23.

Department of Atmospheric Chemistry and Climate Institute of Physical Chemistry Rocasolano CSIC Madrid Spain.

Many Chemistry-Climate Models (CCMs) include a simplified treatment of brominated very short-lived (VSL) species by assuming CHBr as a surrogate for VSL. However, neglecting a comprehensive treatment of VSL in CCMs may yield an unrealistic representation of the associated impacts. Here, we use the Community Atmospheric Model with Chemistry (CAM-Chem) CCM to quantify the tropospheric and stratospheric changes between various VSL chemical approaches with increasing degrees of complexity (i. Read More