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NASA NTRS1998

Effects of 2-deoxy-D-glucose administration on immune parameters in mice

Physical exercise and diet alterations have been shown to affect immune parameters. Similar effects are also induced by the administration of the non-metabolizable glucose analog, 2-deoxy-D-glucose (2-DG). The current study was designed to characterize the effects of glucoprivation induced by 2-DG administration on leukocyte subset distribution and function. BDF1 mice (n = 8 per group) were injected intraperitoneally one or three times with 0, 500, 750, 1000 or 1500 mg/kg of 2-DG. Two hours after the last injection of 2-DG, immunological parameters were analyzed. A dose-dependent increase in plasma glucose concentrations of mice injected once with up to 1500 mg/kg of 2-DG was observed (p < 0.001). After either one or three injections of up to 1500 mg/kg of 2-DG, corticosterone levels, leukocyte counts in the spleen, and CD3+ cells in the thymus increased. In vitro proliferation of partially purified lymphocytes from the spleen in the presence of both concanavalin-A and lipopolysaccharide decreased in a dose dependent manner (p < 0.05). In addition, after three injections, the proportion of both thymocytes and splenocytes bearing alphabeta-TCR increased as the concentration of 2-DG increased (p < 0.01). These results demonstrate that 2-DG administration induced dose-dependent changes in both thymus and spleen cell distribution and function.

NASA Discipline Regulatory Physiology↗

NASA NTRS2008

Providing Internet Access to High-Resolution Lunar Images

The OnMoon server is a computer program that provides Internet access to high-resolution Lunar images, maps, and elevation data, all suitable for use in geographical information system (GIS) software for generating images, maps, and computational models of the Moon. The OnMoon server implements the Open Geospatial Consortium (OGC) Web Map Service (WMS) server protocol and supports Moon-specific extensions. Unlike other Internet map servers that provide Lunar data using an Earth coordinate system, the OnMoon server supports encoding of data in Moon-specific coordinate systems. The OnMoon server offers access to most of the available high-resolution Lunar image and elevation data. This server can generate image and map files in the tagged image file format (TIFF) or the Joint Photographic Experts Group (JPEG), 8- or 16-bit Portable Network Graphics (PNG), or Keyhole Markup Language (KML) format. Image control is provided by use of the OGC Style Layer Descriptor (SLD) protocol. Full-precision spectral arithmetic processing is also available, by use of a custom SLD extension. This server can dynamically add shaded relief based on the Lunar elevation to any image layer. This server also implements tiled WMS protocol and super-overlay KML for high-performance client application programs.

Plesea, Lucian↗

NASA NTRS2018

Challenges in Development of Online Visualization and Analysis Tools for Satellite Data

Over the years, various online visualization and analysis tools have been developed to facilitate satellite data access and help scientific users around the world to conduct research and develop applications (e.g., data product evaluation, what-if questions, etc.). For those who are new to satellite data products, using them can be a daunting task due to many obstacles in data processing such as data formats, complex data structures, special software packages, unfamiliar terminology, etc., especially when one is not sure whether a dataset is suitable for his/er research project. Even for experienced users, developing software for data processing and analysis can be a costly and time-consuming task. Online visualization tools can overcome many of these difficulties and allow users to focus on scientific questions. For example, Giovanni (the Geospatial Interactive Online Visualization and Analysis Infrastructure, https://giovanni.gsfc.nasa.gov), developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC), allows access over 1900 satellite and model variables in 82 measurement groups of 8 disciplines without downloading data and software. Main features include basic functions for data analysis and visualization, data provenance, output data in different formats (ASCII, NetCDF, GeoTIFF), and more. Over the years, ~1700 peer-reviewed publications in different disciplines have been benefited from Giovanni in research activities (e.g. initial investigation, what-if questions, product evaluation). Despite the success of online visualization and analysis tools, challenges and new opportunities still exist and more can be done with new requirements and technology. Examples are: a) how to increase the efficiency of dataset search by enhancing intuitive aspects; b) how to facilitate interdisciplinary research; c) how to provide data quality information; d) how to engage users to participate in data quality assessment; and more. NASA Earth Observing System Data and Information System (EOSDIS) satellite-based data products are processed at various levels ranging from Level 0 to Level 4. While most users use data products at higher levels (Level-3 and 4), products at lower levels are still important for case studies, algorithm development, ground validation, etc. In this presentation, we will use Giovanni as an example to present and discuss challenges and near-future opportunities for satellite data online visualization and analysis tools.

Liu, Zhong↗

NASA NTRS2014

High Intensity Exercise Countermeasures does not Prevent Orthostatic Intolerance Following Prolonged Bed Rest

Approximately 20% of Space Shuttle astronauts became presyncopal during operational stand and 80deg head‐up tilt tests, and the prevalence of orthostatic intolerance increases after longer missions. Greater than 60% of the US astronauts participating in Mir and early International Space Station missions experienced presyncope during post‐flight tilt tests, perhaps related to limitations of the exercise hardware that prevented high intensity exercise training until later ISS missions. The objective of this study was to determine whether an intense resistive and aerobic exercise countermeasure program designed to prevent cardiovascular and musculoskeletal deconditioning during 70 d of bed rest (BR), a space flight analog, would protect against post‐BR orthostatic intolerance. METHODS Twenty‐six subjects were randomly assigned to one of three groups: non‐exercise controls (n=11) or one of two exercise groups (ExA, n=8; ExB, n=7). Both ExA and ExB groups performed the same resistive and aerobic exercise countermeasures during BR, but one exercise group received testosterone supplementation while the other received a placebo during BR in a double‐blinded fashion. On 3 d/wk, subjects performed lower body resistive exercise and 30 min of continuous aerobic exercise (≥75% max heart rate). On the other 3 d/wk, subjects performed only highintensity, interval‐style aerobic exercise. Orthostatic intolerance was assessed using a 15‐min 80 head‐up tilt test performed 2 d (BR‐2) before and on the last day of BR (BR70). Plasma volume was measured using carbon monoxide rebreathing on BR‐3 and before rising on the first recovery day (BR+0). The code for the exercise groups has not been broken, and results are reported here without group identification. RESULTS Only one subject became presyncopal during tilt testing on BR‐2, but 7 of 11 (63%) controls, 3 of 8 (38%) ExA, and 4 of 7 (57%) ExB subjects were presyncopal on BR70. Survival analysis of post‐BR tilt tests revealed no differences (p=0.77) between groups. Plasma volume (absolute or relative to body mass index) decreased (p<0.001) from pre to post‐BR, with no differences between groups. CONCLUSIONS These preliminary results corroborate previous reports that the performance of a vigorous exercise countermeasure protocol during BR, even with testosterone supplementation, does not protect against orthostatic intolerance or plasma volume loss. Preventing post‐BR orthostatic intolerance may require additional countermeasures, such as orthostatic stress during BR or end‐of‐BR fluid infusion.

Platts, Steven H.↗

NASA NTRS1985

Spontaneous running activity in male rats - Effect of age

Variations in the intensity and the patterns of spontaneous running activity in wheel cages were studied in male rats aged 7 weeks to one year. Daily running records were obtained for periods of 12 mo, and 24-hour recordings were made for selected runners in order to study variations in running activity during the day. The data indicate that for rats running over two miles/day, the maximum running intensity can be divided into two groups: a group of high achievers running 8 miles/day; and a group of moderate achievers running 4.8 miles/day. For both groups spontaneous activity reached a maximum after 4-5 weeks. An hourly pattern of running activity during the day was identified in rats of increasing age who averaged 9.0, 4.5, 2.6, and 1.2 miles/day, respectively. Progressive losses were observed in both the speed and the duration of spontaneous running as the rats increased in age, with the intensity of exercise falling below 2 miles/day after 7-8 months of age.

Mondon, C. E.↗

NASA NTRSDate not supplied

Effects of Replacing Treadmill Running with Alternative Exercise Countermeasures During Long-Duration Spaceflight on Astronaut Health and Performance

INTRODUCTION Current exercise countermeasures on the International Space Station (ISS) include treadmill running, cycle ergometry, and resistive exercise, which are used to protect crewmember health and performance during long-duration spaceflight. However, exploration vehicles for Artemis missions to the Moon and beyond will have volume and power restrictions, requiring exercise hardware to have a smaller footprint and use fewer resources. Thus, recent efforts have focused on developing exercise devices that provide both aerobic and resistive capabilities on one platform without including a treadmill. The European Enhanced Exploration Exercise Device [E4D] is one such apparatus. It is critical to validate the efficacy of using exploration-focused exercise modalities to preserve muscle strength, aerobic fitness, bone density, and sensorimotor performance. Thus, the aim of this study is to determine the effectiveness of using nominal ISS exercise devices for an entire mission compared to exploration-forward exercise modalities to determine if a treadmill is required to maintain current levels of protection during long-duration missions. METHODS Crewmembers are assigned to one of three groups: 1) Controls (n ≥ 40), who partake in nominal exercise on the ISS, including running on the Treadmill with Vibration Isolation and Stabilization 2 (T2), cycling on the Cycle Ergometer with Vibration Isolation and Stabilization (CEVIS), and strength training on the Advanced Resistive Exercise Device (ARED); 2) Active Group 1, who exercise on the CEVIS and ARED only (n = 8); and 3) Active Group 2, who perform aerobic and resistive exercise on the E4D only (n = 8). For Active Group 1, nominal exercise on T2 will be replaced with corresponding exercise on CEVIS. For Active Group 2, a dedicated exercise prescription will be designed to maximize the capabilities of the E4D to include resistive exercise, cycle ergometry, rowing, and rope pulling. Crewmembers in both Active groups are not permitted to perform treadmill exercise for the entirety of their flight. Health and performance markers, including bone mineral density (dual-energy x-ray absorptiometry [DXA]), body composition (DXA), cardiovascular fitness (cycle VO2peak), muscle strength and endurance (isometric/isokinetic testing, power endurance testing), sensorimotor performance (sit-to-stand, obstacle course), postural control (computerized dynamic posturography), and blood and urine biochemical markers of bone metabolism will be assessed before, during, and after spaceflight. RESULTS Fifteen subjects (4 Active [CEVIS + ARED], 11 Control) have been recruited. Data collection is ongoing. CONCLUSIONS This study will assess the efficacy of using exploration exercise modalities, including removing the treadmill exercise capability or exclusively using the E4D, compared to the nominal ISS exercise regimen across an entire mission on bone, muscle, aerobic, and sensorimotor health and performance. Findings from this study will help provide a recommendation on whether these exploration exercise modalities can sufficiently protect against physiological deconditioning during spaceflight or whether a treadmill may be required to maintain current levels of protection during future exploration class spaceflight missions. Supported by the NASA Human Research Program and NASA Exploration Capabilities

A N Varanoske↗

NASA NTRSDate not supplied

Effects of Replacing Treadmill Running with Alternative Exercise Countermeasures During Long-Duration Spaceflight

Introduction: Current exercise countermeasures on the International Space Station (ISS), including treadmill running, cycle ergometry, and resistive exercise, are used to protect crewmember health and performance during long-duration spaceflight. However, exploration vehicles for Artemis and beyond will have volume and power restrictions, requiring exercise hardware to have a smaller footprint and use fewer resources. Thus, recent efforts have focused on developing exercise devices that provide both aerobic and resistive training on one platform without including a treadmill, such as the European Enhanced Exploration Exercise Device (E4D). It is critical to validate the efficacy of exploration-focused exercise modalities to preserve muscle strength, aerobic fitness, bone density, and sensorimotor performance. Thus, the aim of this study is to determine the physiological effects of spaceflight that occur with nominal ISS exercise prescriptions compared to exploration-forward exercise modalities to determine if a treadmill is required to maintain current levels of protection during long-duration missions. Methods: Crewmembers will be assigned to one of three groups: 1) Control Group (n ≥ 40) who will partake in nominal exercise on the ISS, including running on the treadmill with vibration isolation system 2 (T2), ergometry on the cycle ergometer with vibration isolation and stabilization device (CEVIS), and strength training on the advanced resistive exercise device (ARED); 2) Active Group 1, who will partake in CEVIS and ARED exercise only (n = 8); and 3) Active Group 2, who will partake in aerobic and resistive exercise on the E4D only (n = 8). For Active Group 1, nominal aerobic exercise on T2 will be replaced with corresponding exercise on CEVIS. For Active Group 2, a dedicated exercise prescription will be designed to maximize the capabilities of the E4D to include resistive exercise, cycle ergometry, rowing, and rope pulling. Crewmembers in both active groups will not be permitted to perform treadmill exercise. Health and performance markers including bone mineral density (dual-energy x-ray absorptiometry [DXA]), body composition (DXA), cardiovascular fitness (cycle VO2peak), muscle strength and endurance (isometric/isokinetic testing, power endurance testing), sensorimotor performance (sit-to-stand, obstacle course), postural control (computerized dynamic posturography), and blood and urine biochemical markers of bone metabolism will be assessed before, during, and following spaceflight. Results: Data collection for this study is currently in progress. Conclusions: This study will assess the efficacy of exploration exercise modalities, including the effects of removing the treadmill exercise capability or of exclusively using the E4D, compared to nominal ISS exercise across an entire mission on bone, muscle, aerobic, and sensorimotor health and performance. Findings from this study will help provide a recommendation on whether these exploration exercise modalities can sufficiently protect against physiological deconditioning during spaceflight or whether a treadmill may be required to maintain current levels of protection during future exploration class spaceflight missions.

A.N. Varanoske↗

NASA NTRSDate not supplied

Effects of Replacing Treadmill Running with Alternative Exercise Countermeasures During Long-Duration Spaceflight

Introduction: Current exercise countermeasures on the International Space Station (ISS), including treadmill running, cycle ergometry, and resistive exercise, are used to protect crewmember health and performance during long-duration spaceflight. However, exploration vehicles for Artemis and beyond will have volume and power restrictions, requiring exercise hardware to have a smaller footprint and use fewer resources. Thus, recent efforts have focused on developing exercise devices (such as the European Enhanced Exploration Exercise Device [E4D]) that provide both aerobic and resistive training on one platform without including a treadmill. It is critical to validate the efficacy of exploration-focused exercise modalities to preserve muscle strength, aerobic fitness, bone density, and sensorimotor performance. Thus, the aim of this study is to determine the physiological effects of spaceflight that occur with nominal ISS exercise prescriptions compared to exploration-forward exercise modalities to determine if a treadmill is required to maintain current levels of protection during long-duration missions. Methods: Crewmembers will be assigned to one of three groups: 1) Control Group (n ≥ 40), who will partake in nominal exercise on the ISS, including running on the Treadmill with Vibration Isolation and Stabilization 2 (T2), ergometry on the Cycle Ergometer with Vibration Isolation and Stabilization (CEVIS) device, and strength training on the Advanced Resistive Exercise Device (ARED); 2) Active Group 1, who will partake in CEVIS and ARED exercise only (n = 8); and 3) Active Group 2, who will partake in aerobic and resistive exercise on the E4D only (n = 8). For Active Group 1, nominal aerobic exercise on T2 will be replaced with corresponding exercise on CEVIS. For Active Group 2, a dedicated exercise prescription will be designed to maximize the capabilities of the E4D to include resistive exercise, cycle ergometry, rowing, and rope pulling. Crewmembers in both active groups will not be permitted to perform treadmill exercise. Health and performance markers including bone mineral density (dual-energy x-ray absorptiometry [DXA]), body composition (DXA), cardiovascular fitness (cycle VO2peak), muscle strength and endurance (isometric/isokinetic testing, power endurance testing), sensorimotor performance (sit-to-stand, obstacle course), postural control (computerized dynamic posturography), Results: Eight subjects (2 Active [CEVIS + ARED], 6 Control) have been recruited for this study. Data collection is currently in progress. Conclusions: This study will assess the efficacy of exploration exercise modalities, including the effects of removing the treadmill exercise capability or of exclusively using the E4D, compared to nominal ISS exercise across an entire mission on bone, muscle, aerobic, and sensorimotor health and performance. Findings from this study will help provide a recommendation on whether these exploration exercise modalities can sufficiently protect against physiological deconditioning during spaceflight or whether a treadmill may be required to maintain current levels of protection during future exploration class spaceflight missions.

A.N. Varanoske↗

NASA NTRSDate not supplied

Effects of Replacing Treadmill Running with Alternative Exercise Countermeasures During Long-Duration Spaceflight

INTRODUCTION: Current exercise countermeasures on the International Space Station (ISS) include treadmill running, cycle ergometry, and resistive exercise, which are used to protect crewmember health and performance during long-duration spaceflight. However, exploration vehicles for Artemis and beyond will have volume and power restrictions, requiring exercise hardware to have a smaller footprint and use fewer resources. Thus, recent efforts have focused on developing exercise devices (such as the European Enhanced Exploration Exercise Device [E4D]) that provide both aerobic and resistive training on one platform without including a treadmill. It is critical to validate the efficacy of exploration-focused exercise modalities to preserve muscle strength, aerobic fitness, bone density, and sensorimotor performance. Thus, the aim of this study is to determine the physiological effects of spaceflight that occur with nominal ISS exercise prescriptions compared to exploration-forward exercise modalities to determine if a treadmill is required to maintain current levels of protection during long-duration missions. METHODS: Crewmembers will be assigned to one of three groups: 1) Control Group (n ≥ 40), who will partake in nominal exercise on the ISS, including running on the Treadmill with Vibration Isolation and Stabilization 2 (T2), ergometry on the Cycle Ergometer with Vibration Isolation and Stabilization (CEVIS) device, and strength training on the Advanced Resistive Exercise Device (ARED); 2) Active Group 1, who will partake in CEVIS and ARED exercise only (n = 8); and 3) Active Group 2, who will partake in aerobic and resistive exercise on the E4D only (n = 8). For Active Group 1, nominal aerobic exercise on T2 will be replaced with corresponding exercise on CEVIS. For Active Group 2, a dedicated exercise prescription will be designed to maximize the capabilities of the E4D to include resistive exercise, cycle ergometry, rowing, and rope pulling. Crewmembers in both active groups will not be permitted to perform treadmill exercise. Health and performance markers including bone mineral density (dual-energy x-ray absorptiometry [DXA]), body composition (DXA), cardiovascular fitness (cycle VO2peak), muscle strength and endurance (isometric/isokinetic testing, power endurance testing), sensorimotor performance (sit-to-stand, obstacle course), postural control (computerized dynamic posturography), and blood and urine biochemical markers of bone metabolism will be assessed before, during, and following spaceflight. RESULTS: Thirteen subjects (3 Active [CEVIS + ARED], 10 Control) have been recruited for this study. Data collection is currently in progress. CONCLUSIONS: This study will assess the efficacy of exploration exercise modalities, including the effects of removing the treadmill exercise capability or of exclusively using the E4D, compared to nominal ISS exercise across an entire mission on bone, muscle, aerobic, and sensorimotor health and performance. Findings from this study will help provide a recommendation on whether these exploration exercise modalities can sufficiently protect against physiological deconditioning during spaceflight or whether a treadmill may be required to maintain current levels of protection during future exploration class spaceflight missions.

A.N. Varanoske↗

NASA NTRSDate not supplied

Effects of Replacing Treadmill Running with Alternative Exercise Countermeasures During Long-Duration Spaceflight

A.N. Varanoske↗

NASA NTRS1996

Cytoplasm-to-myonucleus ratios following microgravity

The cytoplasmic volume-to-myonucleus ratio in the tibialis anterior and gastrocnemius muscles of juvenile rats after 5.4 days of microgravity was studied. Three groups of rats (n = 8 each) were used. The experimental group (space rats) was flown aboard the space shuttle Discovery (NASA, STS-48), while two ground-based groups, one hindlimb suspended (suspended rats), one non-suspended (control), served as controls. Single fibre analysis revealed a significant decrease in cross-sectional area (microns2) in the gastrocnemius for both the space and the suspended rats; in the tibialis anterior only the suspended rats showed a significant decrease. Myonuclei counts (myonuclei per mm) in both the tibialis anterior and gastrocnemius were significantly increased in the space rats but not in the suspended rats. The mean myonuclear volume (individual nuclei: microns3) in tibialis anterior fibres from the space rats, and in gastrocnemius fibres from both the space and the suspended rats, was significantly lower than that in the respective control group. Estimation of the total myonuclear volume (microns3 per.mm), however, revealed no significant differences between the three groups in either the tibialis anterior or gastrocnemius. The described changes in the cross-sectional area and myonuclei numbers resulted in significant decreases in the cytoplasmic volume-to-myonucleus ratio (microns3 x 10(3)) in both muscles and for both space and suspended rats (tibialis anterior; 15.6 +/- 0.6 (space), 17.2 +/- 1.0 (suspended), 20.8 +/- 0.9 (control): gastrocnemius; 13.4 +/- 0.4 (space) and 14.9 +/- 1.1 (suspended) versus 18.1 +/- 1.1 (control)). These results indicate that even short periods of unweighting due to microgravity or limb suspension result in changes in skeletal muscle fibres which lead to significant decreases in the cytoplasmic volume-to-myonucleus ratio.

NASA Discipline Cell Biology↗

DOE OSTI2023

Group additivity values for entropy and heat capacities of C 2 –C 8 alkanes, alkyl hydroperoxides, and their radicals

Group additivity values for the thermodynamic properties of oxygenated radicals are poorly determined due to the absence of high quality reference data. Here, a set of 58 group additive values (GAV) for the standard entropy and heat capacity of relevance to alkane oxidation is derived from fits to an extensive and accurate database of standard entropies (298.15 K) and heat capacities (300–3000 K) recently calculated with the “STAR-1D” formalism. The 192 species in this database represent the alkanes (RH), alkyl radicals ($\dot{R}$), alkyl hydroperoxides (RO 2 H), alkyl-peroxy (R$\dot{O}$ 2 ) and hydroperoxy-alkyl ($\dot{Q}$OOH) radicals for all of the isomers of C 2 –C 5 alkane fuels and a select number of isomers of C 6 –C 9 species. The STAR-1D thermochemical data for this set of species was previously obtained from a coupling of scaled B2PLYPD3/cc-pVTZ vibrational analyses with scaled ωB97X-D/cc-pVTZ one-dimensional hindered rotor corrections. The 2σ uncertainties in the GAV results relative to the STAR-1D data set are 2.4 cal K –1 mol –1 for the entropies and at most 2.0 cal K –1 mol –1 for the heat capacities in the temperature range 500–800 K. The 2σ fitting uncertainties in the heat capacity gradually reduce at higher temperatures reaching a value of 0.8 cal K –1 mol –1 at 2000 K decreasing to only 0.5 cal K –1 mol –1 at 3000 K. The high degree of accuracy for the GAV representations is obtained through the introduction of various new group terms, together with the re-optimization of existing group terms. Among the full set of 58 GAV terms, 25 include non-next-nearest neighbor interactions (NNI) and β-corrections. The updated GAVs can be applied in the prediction of entropies and heat capacities for a wide range of hydrocarbons and hydroperoxide species and their radicals, which is important to the accurate prediction of fuel reactivity at low-temperatures in the range 600–1000 K.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Non-invertible symmetries in finite-group gauge theory

We investigate the invertible and non-invertible symmetries of topological finite-group gauge theories in general spacetime dimensions, where the gauge group can be abelian or non-abelian. We focus in particular on the 0-form symmetry. The gapped domain walls that generate these symmetries are specified by boundary conditions for the gauge fields on either side of the wall. We investigate the fusion rules of these symmetries and their action on other topological defects including the Wilson lines, magnetic fluxes, and gapped boundaries. We illustrate these constructions with various novel examples, including non-invertible electric-magnetic duality symmetry in 3+1d \mathbb{Z}_2 ℤ 2 gauge theory, and non-invertible analogs of electric-magnetic duality symmetry in non-abelian finite-group gauge theories. In particular, we discover topological domain walls that obey Fibonacci fusion rules in 2+1d gauge theory with dihedral gauge group of order 8. We also generalize the Cheshire string defect to analogous defects of general codimensions and gauge groups and show that they form a closed fusion algebra.

Córdova, Clay↗

DOE OSTI2021

The Story of 5d Metallocorroles: From Metal–Ligand Misfits to New Building Blocks for Cancer Phototherapeutics

Porphyrin chemistry is Shakespearean: over a century of study has not withered the field’s apparently infinite variety. Heme proteins continually astonish us with novel molecular mechanisms, while new porphyrin analogues bowl us over with unprecedented optical, electronic, and metal-binding properties. Within the latter domain, corroles occupy a special place, exhibiting a unique and rich coordination chemistry. The 5d metallocorroles are arguably the icing on that cake. New Zealand chemist Penny Brothers has used the word “misfit” to describe the interactions of boron, a small atom with a predilection for tetrahedral coordination, and porphyrins, classic square-planar ligands. Steve Jobs lionized misfits as those who see things differently and push humanity forward. Both perspectives have inspired us. The 5d metallocorroles are misfits in that they encapsulate a large 5d transition metal ion within the tight cavity of a contracted porphyrin ligand. Given the steric mismatch inherent in their structures, the syntheses of some 5d metallocorroles are understandably capricious, proceeding under highly specific conditions and affording poor yields. Three broad approaches may be distinguished. (a) In the metal–alkyl approach, a free-base corrole is exposed to an alkyllithium and the resulting lithio-corrole is treated with an early transition metal chloride; a variant of the method eschews alkyllithium and deploys a transition metal–alkyl instead, resulting in elimination of the alkyl group as an alkane and insertion of the metal into the corrole. This approach is useful for inserting transition metals from groups 4, 5, and, to some extent, 6, as well as lanthanides and actinides. (b) In our laboratory, we have often deployed a low-valent organometallic approach for the middle transition elements (groups 6, 7, 8, and 9). The reagents are low-valent metal–carbonyl or −olefin complexes, which lose one or more carbon ligands at high temperature, affording coordinatively unsaturated, sticky metal fragments that are trapped by the corrole nitrogens. (c) Finally, a metal acetate approach provides the method of choice for gold and platinum insertion (groups 10 and 11). This Account provides a first-hand perspective of the three approaches, focusing on the last two, which were largely developed in our laboratory. In general, the products were characterized with X-ray crystallography, electrochemistry, and a variety of spectroscopic methods. The physicochemical data, supplemented by relativistic DFT calculations, have provided fascinating insights into periodic trends and relativistic effects. An unexpected feature of many 5d metallocorroles, given their misfit character, is their remarkable stability under thermal, chemical, and photochemical stimulation. Many of them also exhibit long triplet lifetimes on the order of 100 μs and effectively sensitize singlet oxygen formation. Many exhibit phosphorescence in the near-infrared under ambient conditions. Furthermore, water-soluble ReO and Au corroles exhibit impressive photocytotoxicity against multiple cancer cell lines, promising potential applications as cancer phototherapeutics. We thus envision a bright future for the compounds as rugged building blocks for new generations of therapeutic and diagnostic (theranostic) agents.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1992

Spectral synthesis in the ultraviolet. IV - A library of mean stellar groups

A library of mean UV stellar energy distributions is derived from IUE spectrophotometry of 218 stars. The spectra cover 1230-3200 A with a spectral resolution of about 6 A. They have been corrected for interstellar extinction and converted to a common flux and wavelength scale. Individual stars were combined into standard groups according to their continuum colors, observed UV spectral morphology, MK luminosity class, and metal abundance. The library consists of 56 groups: 21 dwarf(V), 8 subgiant(IV), 16 giant(III), and supergiant(I + II) groups, covering O3-M4 spectral types. A metal-poor sequence is included, containing four dwarf and two giant groups, as is a metal-enhanced sequence with a single dwarf, subgiant, and giant group. Spectral indices characterizing the continuum and several strong absorption features are examined as temperature, luminosity, and abundance diagnostics. The library is intended to serve as a basis for interpreting the composite UV spectra of a wide variety of stellar systems, e.g., elliptical galaxies, starburst systems, and high-redshift galaxies.

Fanelli, Michael N.↗

DOE OSTI2020

Tuning Zr 12 O 22 Node Defects as Catalytic Sites in the Metal–Organic Framework hcp UiO-66

Defects in metal–organic frameworks (MOFs) play important roles in MOF reactivity and catalysis. Now, we report evidence of the reactivity and the quantitative characterization of the missing linker defects on the Zr 12 O 22 nodes in the MOF hcp UiO-66 (these are paired Zr 6 O 8 nodes bridged by OH groups) and those on the Zr 6 O 8 nodes of the MOF UiO-66. The defect sites catalyze the ring-opening reactions of epoxides with alcohols, and new sites formed by removal of bridging OH groups on the Zr 12 O 22 nodes also participate in the catalysis. The hcp UiO-66 was synthesized from UiO-66 and from molecular precursors, and, under various synthesis conditions, the nodes incorporated acetate ligands, where linkers were missing, and the number of these ligands was controlled by the synthesis conditions. These ligands are inhibitors of the catalytic reactions, and their removal by reaction with, for example, methanol (to form, for example, methyl acetate) preceded catalysis on the defect sites. The former MOF incorporated more defect sites than the latter, correspondingly being a more active catalyst. The defect sites on the Zr 12 O 22 nodes are 2–6 times more active per site than those on the isolated Zr 6 O 8 nodes, with the node-bridging OH groups increasing the catalytic activity of the neighboring node defect sites because new sites are formed by their removal. In conclusion, the results help point the way to the design and control of catalytic sites on metal oxide-like MOF nodes by tuning of the number and reactivity of the defect sites.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2022

Group additivity values for the heat of formation of C 2 –C 8 alkanes, alkyl hydroperoxides, and their radicals

A set of 58 group additivity values (GAV) for the calculation of the heat of formation is derived from an extensive and accurate database of 192 ab initio heats of formation. The ab initio values are from companion calculations at the CCSD(T)–F12/cc-pVTZ-F12//B2PLYPD3/cc-pVTZ level of theory employing second order connectivity based hierarchy reference reactions with ANL energies for the reference species. This database of 192 species consists of alkanes (RH), alkyl radicals ($\dot{\text {R}}$), alkyl hydroperoxides (RO 2 H), alkyl-peroxy (R$\dot{\text {O}}$ 2 ) radicals, and hydroperoxy-alkyl ($\dot{\text {Q}}$OOH) radicals of all of the isomers of C 2 –C 5 alkane fuels and a select set of C 6 –C 8 isomers. The GAV and ab initio based enthalpies for this dataset show excellent agreement, with an estimated 2σ uncertainty of 0.9 kcal mol –1 . Among the 58 GAV terms, 40 are refinements of previously reported terms, while 18 are newly developed. These new GAV terms are mainly non-next-nearest neighbor interactions (NNI) and β-corrections. The inclusion of these new groups significantly improves the accuracy of the GAV estimates of the heats of formation. Finally, the updated GAVs can be used with increased confidence to estimate the heats of formation of combustion relevant hydrocarbons and oxygenated hydrocarbons and their corresponding radicals, which are important in predicting low-temperature chemistry and are critical in the development of accurate chemical kinetic models.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2022

Linking emergent phenomena and broken symmetries through one-dimensional objects and their dot/cross products

Abstract The symmetry of the whole experimental setups, including specific sample environments and measurables, can be compared with that of specimens for observable physical phenomena. We, first, focus on one-dimensional (1D) experimental setups, independent from any spatial rotation around one direction, and show that eight kinds of 1D objects (four; vector-like, the other four; director-like), defined in terms of symmetry, and their dot and cross products are an effective way for the symmetry consideration. The dot products form a Z 2 × Z 2 × Z 2 group with Abelian additive operation, and the cross products form a Z 2 × Z 2 group with Abelian additive operation or Q 8 , a non-Abelian group of order eight, depending on their signs. Those 1D objects are associated with characteristic physical phenomena. When a 3D specimen has symmetry operational similarity (SOS) with (identical or lower, but not higher, symmetries than) an 1D object with a particular phenomenon, the 3D specimen can exhibit the phenomenon. This SOS approach can be a transformative and unconventional avenue for symmetry-guided materials designs and discoveries.

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