Recent publications
During the COVID-19 pandemic changes in human activity became widespread through official policies and organically in response to the virus’s transmission, which in turn, impacted the environment and the economy. The pandemic has been described as a natural experiment that tested how social and economic disruptions impacted different components of the global Earth System. To move this beyond hypotheses, locally-resolved, globally-available measures of how, where, and when human activity changed are critically needed. Here we use satellite-derived nighttime lights to quantify and map daily changes in human activity that are atypical for each urban area globally for two years after the onset of the pandemic using machine learning anomaly detectors. Metrics characterizing changes in lights from pre-COVID baseline in human settlements and quality assurance measures are reported. This dataset, TRacking Anomalous COVID-19 induced changEs in NTL (TRACE-NTL), is the first to resolve COVID-19 disruptions for all metropolitan regions globally, daily. It is suitable to support a variety of post-pandemic studies that assess how changes in human activity impact environmental systems.
In-space biomanufacturing provides a sustainable solution to facilitate long-term, self-sufficient human habitation in extraterrestrial environments. However, its dependence on Earth-supplied feedstocks renders in-space biomanufacturing economically nonviable. Here, we develop a process termed alternative feedstock-driven in-situ biomanufacturing (AF-ISM) to alleviate dependence on Earth-based resupply of feedstocks. Specifically, we investigate three alternative feedstocks (AF)—Martian and Lunar regolith, post-consumer polyethylene terephthalate, and fecal waste—to develop an alternative medium for lycopene production using Rhodococcus jostii PET strain S6 (RPET S6). Our results show that RPET S6 could directly utilize regolith simulant particles as mineral replacements, while the addition of anaerobically pretreated fecal waste synergistically supported its cell growth. Additionally, lycopene production using AF under microgravity conditions achieved levels comparable to those on Earth. Furthermore, an economic analysis shows significant lycopene production cost reductions using AF-ISM versus conventional methods. Overall, this work highlights the viability of AF-ISM for in-space biomanufacturing.
System Vicarious Calibration (SVC) enhances the accuracy of satellite ocean color radiometric data products by removing the bias due to the intrinsic inaccuracies affecting both the responsivity of the space sensor and the correction for the atmospheric and sea surface contributions to the measured signal. Various SVC procedures have been implemented and applied for regional studies, specific mission goals, and the most challenging quantification of global, long-term, climate-driven changes that require accurate and consistent data products across multiple missions. This paper summarizes the outcome of a workshop organized by the Ocean Color SVC Task Force of the International Ocean Color Coordinating Group (IOCCG) to review requirements for SVC supporting ocean color missions for climate and global long-term operational applications. The work emphasizes the essential need for long-term sustained SVC infrastructures and associated services, summarizes the primary requirements for establishing a comprehensive ocean color SVC framework, and provides directions for new investigations to tackle arising needs on SVC advancements and methods.
This paper proposes a new arc-search interior-point algorithm for the nonlinear constrained optimization problem. The proposed algorithm uses the second-order derivatives to construct a search arc that approaches the optimizer. Because the arc stays in the interior set longer than any straight line, it is expected that the scheme will generate a better new iterate than a line search method. The computation of the second-order derivatives requires to solve the second linear system of equations, but the coefficient matrix of the second linear system of equations is the same as the first linear system of equations. Therefore, the matrix decomposition obtained while solving the first linear system of equations can be reused. In addition, most elements of the right-hand side vector of the second linear system of equations are already computed when the coefficient matrix is assembled. Therefore, the computation cost for solving the second linear system of equations is insignificant and the benefit of having a better search scheme is well justified. The convergence of the proposed algorithm is established. Some preliminary test results are reported to demonstrate the merit of the proposed algorithm.
In-cloud aerosol scavenging remains a large source of model uncertainty, affecting capabilities to capture the aerosol lifetime and impacts on air quality and climate. While past work quantified aerosol scavenging efficiencies (SEs) in midlatitude mixed-phase deep convection, SEs are less well-known for shallower convection. We used aircraft data over the tropical West Pacific to calculate SEs for three marine cumuli of different top heights (3 – 7 km above sea level) using a simple entrainment model and measurements of the cloud outflow and nearby clear air. Across cases, efficient scavenging was observed for sulfate (>86%) and black carbon (70 – 80%), while organic aerosols (53 – 60%) and nitrate (61.5%) were moderately scavenged. Ammonium had a wide SE range (53 – 87%). SEs of aerosol volume concentration showed near-total removal of aerosols with diameters greater than 100 nm (>92%) and inefficient removal for aerosols with diameters less than 100 nm (30 – 50%), associated with the preferential activation and removal of larger particles. Mass-based SEs did not differ substantially between tropical cumuli and midlatitude deep convection, attributed to the negligible mass activated at higher supersaturations. The efficient scavenging of BC can be explained by an enhanced hygroscopic fraction of BC based on model results from the CESMv2 Community Atmosphere Model with Chemistry, suggesting the internal mixing of BC with more soluble species during long-range transport through the marine atmosphere. The estimates of BC SEs provide direct evidence of substantial BC removal in convection as inferred by previous work and should motivate improvements in chemical transport models.
Improved thermal management solutions for electrical insulation systems are a priority for increasing efficiency. Although polymeric electrical insulations are ubiquitous, they generally exhibit low thermal conductivities (κ ; 0.1 – 0.3 W/mK). High κ electrical insulation systems are desirable for several reasons including improved heat wicking. Polymer-ceramic composites offer a viable path towards increasing κ of electrical insulation systems without detrimental impact to insulative performance. However, processing-induced anisotropic particle orientation can result in prohibitively high concentrations of ceramic particles required to achieve high κ. This work evaluates the effectiveness of a heterogenous network approach and its impacts on extruded polymer composite insulation κ using polyimide (PI), polyphenylsulfone (PPSU), and hexagonal boron nitride (hBN). Thermoplastic composite blends of PI/PPSU exhibited a 15% improvement in composite κ at comparable loading levels of hBN relative to homopolymer networks. On the other hand, PI/PPSU/hBN composites exhibited lower dielectric strengths than homopolymer/hBN composites. A trade-off between material κ and dielectric performance appears to exist when using a heterogenous network approach for thermoplastic composites.
The pristine Himalayas are sensitive to pollutants from different source regions, including its foothills that have adverse effects on air quality and climate. Despite this, there are no observations of aromatic hydrocarbons in the central Himalayas. Thus, online observations of aromatics (C6-C8, defined here as BTEX) were conducted for the first time at the mountain site (Nainital, 1958 m) in the central Himalayas during January 2017-December 2022 period. Additionally, observations were made at a foothill site in the Indo-Gangetic Plain (Haldwani, 554 m) to assess the source features. The diurnal variations at the mountain site were characterised by daytime higher BTEX (~ 6 ppbv), in-contrast the IGP foothill site exhibited nighttime elevated levels (~ 19 ppbv). Higher values were exhibited in spring and autumn at the mountain site, while values were higher in winter at the IGP foothill site. These variations were primarily influenced by the transport of diverse air masses to the mountain site, while the role of local emissions was found at the IGP foothill site. The boundary layer processes play a role at both sites, but differently. Xylene was the most abundant (60–65%) at both sites, suggesting the influence of emissions from the IGP region. This contrasts with the composition used in emission inventories for this region. The toluene to benzene ratio at mountain (4.5) and IGP foothill (5.3) sites and ternary plots indicated the dominance of industrial/vehicular sources, with some contributions from biomass burning. The estimated OH reactivity, ozone formation potential and secondary organic aerosol formation potential were found to be 4–6 times greater at the IGP foothill site than those at the mountain site. Xylene played a significant role in these processes at both sites. Furthermore, benzene played a dominant role in the hazard ratio and the lifetime cancer risk (LCR) at both sites. The LCR at both sites crossed the probable risk limit.
Background
The rate of suicide attempts by patients with bipolar disorder is high. In addition to patient and country specific factors, environmental factors may contribute to suicidal behavior. Sunlight has multiple diverse impacts on human physiology and behavior. Solar insolation is defined as the electromagnetic energy from the sun striking a surface area on earth. We previously found that a large change in solar insolation between the minimum and maximum monthly values was associated with an increased risk of suicide attempts in patients with bipolar I disorder.
Methods
The association between solar insolation and a history of suicide attempts in bipolar disorder was again investigated using an international database with 15% more data and more sites at diverse locations and countries.
Results
Data were available from 5641 patients with bipolar I disorder living at a wide range of latitudes in 41 countries in both hemispheres. A large change in solar insolation between the minimum and maximum monthly values was associated with a history of suicide attempts in patients with bipolar I disorder, a replication of our prior analysis. The estimated model also associated state sponsored religion in the onset country, female gender, a history of alcohol or substance abuse, and being part of a younger birth cohort with a history of suicide attempts.
Conclusions
A large change between the minimum and maximum monthly values of solar insolation was associated with a history of suicide attempts in bipolar I disorder, replicating our prior research. Physicians should be aware that daylight has wide ranging physiological and psychiatric impacts, and that living with large changes in solar insolation may be associated with an increased suicide risk.
This work reports on an attempt toward improving the Relativistic Electron Alert System for Exploration (REleASE): the occurrence of a type‐III radio burst as a precondition for a REleASE forecast. REleASE forecasts are based on the detection of early arrival of near‐relativistic electrons ahead of more hazardous protons from Solar Energetic Particle (SEP) events. The goal is to allow astronauts on a Lunar or Mars mission sufficient advance warning to reach a radiation shelter to minimize radiation dose exposure. We test a new system that sets a condition of the occurrence of a type‐III radio burst, thus adding independent evidence of particle escape from the Sun, with the aim of reducing known sources of false‐alarms of the existing REleASE system. The High Energy Solar Particle Events foRecastIng and Analysis (HESPERIA) REleASE+ system, which takes advantage of availability of real‐time solar radio observations during the passage of STEREO‐A by Earth in 2023, has now been incorporated in the HESPERIA framework. We discuss the techniques used for automatic detection of type‐III radio bursts preparing for its real‐time implementation, the determination of selection criteria for type‐III bursts that are candidates for solar proton events in the Earth‐moon system, and first results of the combined system.
Objectives:
Hydrazine (HZ) and Hydrazine Derivative (HZ-D) exposures pose health risks to people in industrial and aerospace settings. Several recent systematic reviews and case series have highlighted common clinical presentations and management strategies. Given the low frequency at which HZ and HZ-D exposures occur, a strong evidence base on which to develop an evidence-based guideline does not exist at this time. Therefore, the aim of this project is to establish a consensus guideline for prehospital care of patients with exposures to HZ and HZ-Ds.
Methods:
A modified Delphi technique was used to develop clinical questions, obtain expert panel opinions, develop initial patient care recommendations, and revise the draft into a final consensus guideline. First, individuals (Emergency Medical Services (EMS) physicians and hazardous materials technicians) with experience in management of HZ and HZ-Ds identified relevant clinical questions. An expert panel was then convened to make clinical recommendations. In the first round, the panel voted on clinical care recommendations. These recommendations were drafted into a guideline that expert panel members reviewed. After review, additional unanswered questions were discussed electronically by expert panel members, and electronic votes were cast. Ultimately, patient care recommendations were condensed into a concise, consensus guideline.
Results:
Eight clinical questions regarding treatment of patients with HZ and HZ-D exposures were identified. These questions were reviewed by the expert panel which included 2 representatives from: aerospace medicine, military medicine, EMS medicine, paramedicine, pharmacy, and toxicology. Draft patient care recommendations generated three additional questions which were discussed electronically and voted on. These recommendations were then formatted into a guideline outlining recommendations for care prior to decontamination, during decontamination, and after decontamination.
Conclusions:
The consensus guideline for clinical care of patients with exposure to HZ/HZ-Ds is as follows: Prior to decontamination, use appropriate personal protective equipment, and when necessary, support ventilation using a bag-valve-mask and administer midazolam intramuscularly for seizures. After decontamination, provide supplemental oxygen; consider selective advanced airway management when indicated; administer inhaled beta-agonists for wheezing; and, for seizures unresponsive to multiple doses of benzodiazepines that occur during pre-planned, high-hazard activities, such as spacecraft recovery, consider intravenous or intraosseous pyridoxine.
The Arabian Gulf (AG) exports hypersaline, dense waters into the Sea of Oman (SOO), replaced by fresher inflowing surface waters from the Indian Ocean. We investigate the impact of recent AG warming on its exchange with the SOO and the implications this has on the AG biogeochemistry. Using an eddy‐resolving hindcast model simulation, we analyze the hydrography and biogeochemistry of the AG and the SOO from 1980 to 2018. Our study reveals that changes in summer surface winds have accelerated AG warming and weakened it in the SOO, reducing the density gradient and water exchange between the two seas during late summer. This has led to nutrient buildup, increased productivity, and heightened deoxygenation and acidification in the AG. These findings underscore how subtle wind changes can exacerbate the vulnerability of marginal seas to climate change and stress the need to properly represent regional winds in global climate models.
Precipitation into the atmosphere is one of the main processes by which high energy electrons trapped in Earth's inner magnetosphere are lost from the system. Precipitating electrons can affect the chemical composition of the atmosphere and provide insight into the complex dynamics of the Van Allen radiation belts. This study compares energetic electron precipitation measurements at low‐Earth‐orbit by the Focused Investigations of Relativistic Electron Burst Intensity, Range, and Dynamics (FIREBIRD‐II) CubeSats with NOAA Polar‐orbiting Operational Environmental Satellite (POES) and ESA Meteorological Operational satellite (MetOp) satellites, which are equipped with the Medium‐Energy Proton Electron Detector (MEPED). The analysis considers 51 high quality conjunction events at >300 keV during times of low to moderate geomagnetic activity. The spacecraft capture similar electron flux variability, and FIREBIRD‐II observations fall between POES/MetOp 0° and 90° telescopes, likely a result of FIREBIRD‐II sampling both precipitating and mirrored electrons due to uncertainties in pointing direction. Results demonstrate the value of high‐resolution differential energy observations of electron precipitation by low‐cost CubeSats such as FIREBIRD‐II, especially during periods of low flux.
Many biological markers of normal and disease states can be detected in saliva. The benefits of saliva collection for research include being non-invasive, ease of frequent sample collection, saving time, and being cost-effective. A small volume (≈1 mL) of saliva is enough for these analyses that can be collected in just a few minutes. For “dry” saliva paper matrices, additional drying times (about 30 min) may be needed, but this can be performed at room temperature without the need for freezers and specialized equipment. Together, these make saliva an ideal choice of body fluid for many clinical studies from diagnosis to monitoring measurable biological substances in hospital settings, remote, and other general locations including disaster areas. For these reasons, we have been using saliva (dry as well as wet) from astronauts participating in short- and long-duration space missions for over two decades to conduct viral, stress, and immunological studies. We have also extended the use of saliva to space analogs including bed rest, Antarctica, and closed-chamber studies. Saliva is a biomarker-rich and easily accessible body fluid that could enable larger and faster public health screenings, earlier disease detection, and improved patient outcomes. This review summarizes our lessons learned from utilizing saliva in spaceflight research and highlights the advantages and disadvantages of saliva in clinical diagnostics.
The Joint Polar Satellite System 3 (JPSS-3) and 4 (JPSS-4) Visible Infrared Imaging Radiometer Suite (VIIRS) are the fourth and fifth in its series of instruments designed to provide high-quality data products for environmental and climate data records. The VIIRS instrument must be calibrated and characterized prior to launch to meet the data product needs. A comprehensive test program was conducted at the Raytheon Technologies facility in 2020 (JPSS-3) and 2023 (JPSS-4) that included extensive functional and environmental testing. The thermal band radiometric pre-launch performance and stability are the focus of this article, which also compares several instrument performance metrics to the design requirements. Brief comparisons with the JPSS-1 and -2 VIIRS instrument performance will also be discussed.
The amount of and changes in a country’s natural assets are crucial for developing national strategic plans and policies due to their foundational role in determining the resilience of social-environmental systems (SES), especially under a changing climate. Many integrated metrics on natural assets have been proposed based on individual measures to provide insights into the state of national natural resources. This is particularly true for countries experiencing extreme environmental stresses. Drawing on longitudinal data spanning from 1980 to 2020, the objective of this study is to analyze nuanced distinctions across 23 political entities (PEs) in the dryland regions of mid-latitudinal Asia, investigating their interannual variabilities over the four-decade study period and discerning potential driving forces. We examined three key integrated measures of the SES: ecosystem water use efficiency, human appropriation of net primary production, and human appropriation of water resources. We found increased variability as well as spikes in extreme values in each of these three measures of SES function among the 23 PEs over the study period. Water stress played an increasing and more important role than temperature in influencing the magnitude and variations of the three measures. Our results also indicate that human interventions may help increase the efficiency of water use in this dryland region of the world.
Astronomers have found more than a dozen planets transiting stars that are 10–40 million years old¹, but younger transiting planets have remained elusive. The lack of such discoveries may be because planets have not fully formed at this age or because our view is blocked by the protoplanetary disk. However, we now know that many outer disks are warped or broken²; provided the inner disk is depleted, transiting planets may thus be visible. Here we report observations of the transiting planet IRAS 04125+2902 b orbiting a 3-million-year-old, 0.7-solar-mass, pre-main-sequence star in the Taurus Molecular Cloud. The host star harbours a nearly face-on (30 degrees inclination) transitional disk³ and a wide binary companion. The planet has a period of 8.83 days, a radius of 10.7 Earth radii (0.96 Jupiter radii) and a 95%-confidence upper limit on its mass of 90 Earth masses (0.3 Jupiter masses) from radial-velocity measurements, making it a possible precursor of the super-Earths and sub-Neptunes frequently found around main-sequence stars. The rotational broadening of the star and the orbit of the wide (4 arcseconds, 635 astronomical units) companion are both consistent with edge-on orientations. Thus, all components of the system are consistent with alignment except the outer disk; the origin of this misalignment is unclear.
The term “nanotechnology,” or “nanoscience,” refers to the science carried out on a nanometer scale and alludes to structures having a dimension between 1 and 100 nm. In the last 20 years alone, the nanoneuroscience and nanoneurosurgery fields have emerged as new frontiers of science, leading to astonishing advancements in biomedical science and clinical practice. Nanotechnology emerged as a field of study in the twentieth century with Richard Feynman, Norio Taniguchi, Eric Drexler, and Robert A. Freitas Jr as some of the original visionaries who set a course that would lead to the application of nanomechanical concepts in neurosurgery and nanoneurosurgery. After the discovery of carbon nanoparticles and nanotubes in the late twentieth century, there was a major growth of interest in the application of nanotechnology in material, electrical, and optical engineering. Not long after, a search for applications in biomedical science began, finding uses in drug delivery, nucleic acid/macromolecule delivery, imaging, and as an interface to treat disorders and injuries. Nanomedicine for a neurological or neurosurgical application has not yet been approved by the Food and Drug Administration (FDA); however, a variety of nanoplatforms for biomedical applications are available for research and clinical trials. The continuation of nanotechnology and neuroscience research relies in part on the collaborative efforts of the US Congress. The National Nanotechnology Initiative (NNI) was launched in 2000 by President Clinton to help fund the development of nanotechnologies applicable to neurosurgical uses. The United States Congressional Neuroscience Caucus has a mission to raise awareness of the importance of neuroscience research in the hope of spurring support from society and federal policy.
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