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Previous efforts to measure atmospheric iodine have focused on marine and coastal regions. We report the first ground‐based tropospheric iodine monoxide (IO) radical observations over the central continental United States. Throughout April 2022, IO columns above Storm Peak Laboratory, Colorado (3,220 m.a.s.l.) ranged from 0.7 ± 0.5 to 3.6 ± 0.5 × 1012 (average: 1.9 × 1012 molec cm−2). IO was consistently elevated in air masses transported from over the Pacific Ocean. The observed IO columns were up to three times higher and the range was larger than predicted by a global model, which warrants further investigation into iodine sources, sinks, ozone loss, and particle formation. IO mixing ratios increased with altitude. At the observed levels, iodine may be competitive with bromine as an oxidant of elemental mercury at cold temperatures typical of the free troposphere. Iodine‐induced mercury oxidation is missing in atmospheric models, understudied, and helps explain model underestimation of oxidized mercury measurements. Plain Language Summary: Halogens such as chlorine, bromine, and iodine are highly reactive gases that participate in atmospheric chemistry, including ozone destruction, particle formation, modification of greenhouse gas lifetime (i.e., methane, dimethylsulfide), and the oxidation of elemental mercury. Iodine mainly enters the atmosphere from oceans; therefore, past measurements of atmospheric iodine have focused on marine and polar regions. This study describes the first lower atmospheric measurements of iodine monoxide (IO) radicals at a remote mountaintop site in the central continental United States. These measurements indicate that the concentration of IO radicals showed a large range over the course of 1 month and reached levels up to three times higher than predicted by a global atmospheric chemistry model. These observations suggest that our understanding of the iodine sources and sinks to the free troposphere may be incomplete. Moreover, we suggest that iodine's contribution to ozone destruction and mercury chemistry may be underestimated; in particular, iodine may be competitive with bromine in the oxidation of elemental mercury in the free troposphere. Key Points: Measurements of iodine monoxide radicals at Storm Peak Laboratory are up to three times higher than predicted by GEOS‐ChemIO tropospheric column variability is significant and highlights a need to better understand sources and sinks of tropospheric iodineIodine may rival bromine as a tropospheric mercury oxidant; iodine‐mercury chemistry is understudied and missing in atmospheric models [ABSTRACT FROM AUTHOR] more...

New features in the dose estimation program RADDOSE‐3D are summarised. They include the facility to enter a diffraction intensity decay model which modifies the "Diffraction Weighted Dose" output from a "Fluence Weighted Dose" to a "Diffraction‐Decay Weighted Dose", a description of RADDOSE‐ED for use in electron diffraction experiments, where dose is historically quoted in electrons/Å2 rather than in gray (Gy), and finally the development of a RADDOSE‐3D GUI, enabling easy access to all the options available in the program. [ABSTRACT FROM AUTHOR] more...

Animal behavior is a useful way to evaluate the environment and can be a predictive tool to assess not only the effects of treatments in a laboratory setting, but also the status of ecological habitats. As invasive species of crayfish encroach on territories of native species, the social behaviors and interactions can be informative for ecological studies. For a wider and more impactful effect, training community scientists using a scoring system to record the social interactions of crayfish that includes both the level of aggression and intensity would provide useable data to monitor the environment. Amateur scientists with little training were fairly reliable in their average scoring of the crayfish and the maximum behavior score with an expert as well as among themselves. However, the number of interactions was not as a reliable metric to compare with the expert or just among the amateurs. [ABSTRACT FROM AUTHOR] more...

Understanding equitable practice is crucial for science education since science, technology, engineering, and mathematics (STEM) fields and STEM learning practices remain significantly marked by structural inequalities. In this paper, building on theories of discourse and situated meaning developed by Foucault, Gee, and Sedgewick, we explore how educators navigated discourses about social justice in informal science learning (ISL) across four UK sites. We draw on qualitative, multimodal data across 5 years of a research–practice partnership between a university, a zoo, a social enterprise working to support girls and nonbinary youth in STEM, a community digital arts center, and a science center. We identify three key discourses that shaped social justice practices across all four practice–partner sites: (1) "inclusion" for STEM, (2) "inclusion" for the institution, and (3) "inclusion" for minoritized youth. We discuss how educators (n = 17) enacted, negotiated, resisted, and reworked these discourses to create equitable practice. We argue that while the three key discourses shaped the possible meanings and practices of equitable ISL in different ways, educators used their agency and creativity to develop more expansive visions of social justice. We discuss how the affordances, pitfalls, and contradictions that emerged within and between the three discourses were strategically navigated and disrupted by educators to support the minoritized youth they worked with, as well as to protect and promote equity in ISL. This paper contributes to research on social justice in ISL by grounding sometimes abstract questions about power and discourse in ISL educators' everyday work. [ABSTRACT FROM AUTHOR] more...

Gas fermentation of CO2 and H2 is an attractive means to sustainably produce fuels and chemicals. Clostridium autoethanogenum is a model organism for industrial CO to ethanol and presents an opportunity for CO2‐to‐ethanol processes. As we have previously characterized its CO2/H2 chemostat growth, here we use adaptive laboratory evolution (ALE) with the aim of improving growth with CO2/H2. Seven ALE lineages were generated, all with improved specific growth rates. ALE conducted in the presence of 2% CO along with CO2/H2 generated Evolved lineage D, which showed the highest ethanol titres amongst all the ALE lineages during the fermentation of CO2/H2. Chemostat comparison against the parental strain shows no change in acetate or ethanol production, while Evolved D could achieve a higher maximum dilution rate. Multi‐omics analyses at steady state revealed that Evolved D has widespread proteome and intracellular metabolome changes. However, the uptake and production rates and titres remain unaltered until investigating their maximum dilution rate. Yet, we provide numerous insights into CO2/H2 metabolism via these multi‐omics data and link these results to mutations, suggesting novel targets for metabolic engineering in this bacterium. [ABSTRACT FROM AUTHOR] more...

We analyzed 12 Apollo 17 samples through the Apollo Next Generation Sample Analysis (ANGSA) program to determine the abundances of a variety of compound classes, including amino acids, aldehydes, ketones, amines, carboxylic acids, and cyanide‐releasing species. Analyzed samples included portions of double drive tube 73001/73002, the bottom half of which (73001) was hermetically sealed under lunar vacuum, as well as lunar regolith samples from three different illumination environments that had been curated frozen for ∼50 years. Consistent with previous results, we detected low levels of amino acids in the hot‐water extracts of most samples (0.55–12.03 nmol/g in unhydrolyzed samples; 0.53–72.38 nmol/g after acid hydrolysis of the extracts). We also detected one‐carbon and two‐carbon species of amines, aldehydes, and carboxylic acids (i.e., methylamine, ethylamine, formaldehyde, acetaldehyde, formic acid, acetic acid) not previously reported in lunar samples, as well as insoluble cyanide‐forming species. Although these compounds are potential precursor molecules for amino acids, no specific precursor relationships could be determined. Nylon contamination was the likely source of some amino acids. Abundances of some species (e.g., cyanide) decreased with increasing depth in the drive tube, suggesting that exogenous delivery and concentration mechanisms near the surface outweighed surface degradation processes. In addition, we observed the potential cold trapping of volatile amines in the persistently shadowed samples analyzed. Finally, we noted the effects of different curation conditions; hermetic sealing appeared to preserve higher amounts of volatile compounds, while frozen curation did not have a noticeable preservation effect on the organic volatiles analyzed here. Plain Language Summary: The Moon's surface may contain organic chemicals similar to those used by life on Earth, but previous studies have been limited. Some of the Moon rocks and dirt collected in 1973 by the Apollo 17 astronauts were set aside for future generations to study after new techniques could be developed. Recently, after nearly 50 years in curation, some of these samples were made available to researchers, including samples that had been sealed by astronauts on the lunar surface and not exposed to the Earth's atmosphere, as well as samples that were stored in a freezer after return to Earth. We examined these samples along with other Apollo 17 samples to search for small organic chemicals such as amino acids (like those in proteins in life on Earth) and related molecules. We found small amounts of volatile compounds such as formaldehyde, which had not previously been detected in Moon samples. We also found that storing the samples in special sealed containers may better preserve volatile chemicals, while freezing did not have a strong effect on the chemicals we examined. These results help us understand the chemical environment of the Moon and provide lessons for the storage of future returned samples. Key Points: Low (nmol/g) abundances of volatile organic compounds were detected in specially curated Apollo 17 samplesWe observed amino acids, cyanides, amines, aldehydes, ketones, and carboxylic acids, including some not previously known in lunar samplesHermetically sealed curation better preserved certain volatile compounds, while frozen curation may reduce organic contamination [ABSTRACT FROM AUTHOR] more...

In 1972, Apollo 17 astronauts returned 170.4 kg of lunar material. Within 1 month of their return, a subset of those samples was specially curated with the forethought that future analytical techniques would offer new insight into the formation and evolution of the Moon. Of interest in this work is sample 71036, a basalt collected from the rim of Steno crater in the Taurus–Littrow Valley, which was stored frozen and was processed and released for study 50 years later. We report, for the first time, the detailed mineralogy and petrology of 71036 and its companion samples 71035, 71037, and 71055 using a novel combination of 2‐D and 3‐D methods. We investigate lunar volatiles through in situ measurements of apatite and 3‐D measurements of vesicles to understand the degassing histories of the Steno crater basalts. Our coupled 2‐D petrography and 3‐D tomography data sets support a model of the Steno crater basalts crystallizing in the upper crust of a mare lava flow. Apatite F and OH chemistry and the late‐stage deformation of voids and formation of smaller vesicles provide evidence supporting coeval degassing of volatiles and crystallization of mesostasis apatite in Apollo 17 basalts. This work helps to close knowledge gaps surrounding the origin, magmatic evolution, emplacement, and crystallization history of high‐titanium basalts. [ABSTRACT FROM AUTHOR] more...

SUMMARY: Although primary metabolism is well conserved across species, it is useful to explore the specificity of its network to assess the extent to which some pathways may contribute to particular outcomes. Constraint‐based metabolic modelling is an established framework for predicting metabolic fluxes and phenotypes and helps to explore how the plant metabolic network delivers specific outcomes from temporal series. After describing the main physiological traits during fruit development, we confirmed the correlations between fruit relative growth rate (RGR), protein content and time to maturity. Then a constraint‐based method is applied to a panel of eight fruit species with a knowledge‐based metabolic model of heterotrophic cells describing a generic metabolic network of primary metabolism. The metabolic fluxes are estimated by constraining the model using a large set of metabolites and compounds quantified throughout fruit development. Multivariate analyses showed a clear common pattern of flux distribution during fruit development with differences between fast‐ and slow‐growing fruits. Only the latter fruits mobilise the tricarboxylic acid cycle in addition to glycolysis, leading to a higher rate of respiration. More surprisingly, to balance nitrogen, the model suggests, on the one hand, nitrogen uptake by nitrate reductase to support a high RGR at early stages of cucumber and, on the other hand, the accumulation of alkaloids during ripening of pepper and eggplant. Finally, building virtual fruits by combining 12 biomass compounds shows that the growth‐defence trade‐off is supported mainly by cell wall synthesis for fast‐growing fruits and by total polyphenols accumulation for slow‐growing fruits. Significance Statement: This work shows how a panel of eight fruit species unravels specific metabolic flux patterns throughout fruit development. For this, a medium‐size metabolic model of primary metabolism is constrained by compositional time‐series data. The predicted metabolic fluxes highlight a growth‐defence trade‐off with high nitrogen uptake and carbon used in cell wall synthesis for fast‐growing fruits from herbaceous plants. Conversely, slow‐growing fruits, from trees, require the tricarboxylic acid cycle for early phenolic compounds synthesis. [ABSTRACT FROM AUTHOR] more...

Mercury, the innermost planet, formed under highly reduced conditions, based mainly on surface Fe, S, and Si abundances determined from MESSENGER mission data. The minor element Cr may serve as an independent oxybarometer but only very limited Cr data have been previously reported for Mercury. We report Cr/Si abundances across Mercury's surface based on MESSENGER X‐Ray Spectrometer data throughout the spacecraft's orbital mission. The heterogeneous Cr/Si ratio ranges from 3.6 × 10−5 in the Caloris Basin to 0.0012 within the high‐magnesium region, with an average southern hemisphere value of 0.0008 (corresponding to about 200 ppm Cr). Absolute Cr/Si values have systematic uncertainty of at least 30%, but relative variations are more robust. By combining experimental Cr partitioning data along with planetary differentiation modeling, we find that if Mercury formed with bulk chondritic Cr/Al, Cr must be present in the planet's core and differentiation must have occurred at log fO2 in the range of IW‐6.5 to IW‐2.5 in the absence of sulfides in its interior and a range of IW‐5.5 to IW‐2 with an FeS layer at the core‐mantle boundary. Models with large fractions of Mg‐Ca‐rich sulfides in Mercury's interior are more compatible with moderately reducing conditions (IW‐5.5 to IW‐4) owing to the instability of Mg‐Ca‐rich sulfides at elevated fO2. These results indicate that if Mercury differentiated at a log fO2 lower than IW‐5.5, the presence of sulfides whether in the form of a FeS layer at the top of the core or Mg‐Ca‐rich sulfides within the mantle would be unlikely. Plain Language Summary: Data returned by NASA's MESSENGER mission, which orbited Mercury from 2011 to 2015, have shown that the innermost planet formed under highly reducing (relatively low‐oxygen) conditions, compared to the other terrestrial planets, but estimates of Mercury's oxidation state are highly uncertain. Chromium, a minor element in planetary materials, can exist in a wide range of oxidation states and its abundance thus can provide information about the chemical conditions under which it was incorporated into rocks. We used data from MESSENGER's X‐ray Spectrometer instrument to map the Cr/Si ratio across much of Mercury and found that Cr is heterogeneously distributed. By comparing the average measured Cr abundance to the results of planetary differentiation models (informed by experimental data on how Cr partitions between different phases under different planetary differentiation conditions), we placed new constraints on Mercury's oxidation state and show that further refinement of this quantity could be used to place limits on the presence of sulfides in the planet's deep interior. Key Points: Chromium abundance is useful as a probe of redox conditions during planet formation and evolutionWe used MESSENGER x‐ray fluorescence data to determine whether surface Cr abundance is heterogeneous on Mercury with an average value of ∼200 ppmExperimental data and differentiation modeling put constraints on Mercury's oxidation state, depending on the presence of mantle sulfides [ABSTRACT FROM AUTHOR] more...

Evidence suggests the focus for sodium replacement during exercise should be maintenance of plasma sodium concentration ([Na+]plasma) for any given total body water (TBW) volume. The sodium intake to achieve stable [Na+]plasma given known fluid and electrolyte intakes and losses can be mathematically estimated. Therefore the aim of this investigation was to model sodium requirements of athletes during exercise, observing the influence of sweat rate, exercise duration, body mass, baseline [Na+]plasma and sweat potassium [K+]sweat, and relevance to competition (soccer, elite marathon, and 160 km ultramarathon running). Models were constructed across a range of sweat sodium concentrations ([Na+]sweat) (20–80 mmol·L−1), sweat rates (0.5–2.5 L·h−1) and fluid replacement (10–90% of losses). In the competition-specific scenarios, fluid replacement was calculated to achieve 2% TBW losses. Sodium requirements were driven by fluid replacement (% of losses) and [Na+]sweat, with minimal or no influence of other variables. Replacing sodium was unnecessary in all realistic scenarios modelled for a soccer match and elite marathon. In contrast, the 160 km ultramarathon required ≥47% sodium replacement when [Na+]sweat was ≥40 mmol·L−1 and >80% of fluid losses were replaced. In conclusion, sodium requirements to maintain stable [Na+]plasma during exercise depend on both the proportion of fluid losses replaced, and [Na+]sweat. Only when prolonged exercise is coupled with aggressive fluid replacement (>80%) and whole body [Na+]sweat ≥40 mmol·L−1 does sweat composition testing and significant, targeted sodium replacement appear necessary. Highlights Modelling sodium intake requirements with sodium and fluid intake expressed as a proportion of losses, allows robust models to be constructed that are not influenced by sweat rate, exercise duration, body mass, and only to a minor extent by baseline plasma sodium and sweat potassium. When applied to specific sporting scenarios, targeted sodium replacement, and therefore sweat composition testing, appears unnecessary in all realistic scenarios modelled for a soccer match or elite marathon race. Athletes can therefore choose sodium intake according to taste preferences rather than physiological need. During a 160 km ultramarathon, targeted sodium replacement may be necessary because fluid replacement needs are greater as a proportion of losses. However the required quantity remains <50% of losses unless sweat rate is ≥1.5 L·hr−1, sweat sodium is ≥40 mmol·L−1, and fluid replacement is ≥90% of losses. The modelling technique described could be utilised by researchers to personalise sodium replacement in intervention studies for each participant, or by practitioners to either estimate the likely sodium needs of athletes during exercise, or to decide when sweat composition testing is or is not likely to be useful. [ABSTRACT FROM AUTHOR] more...

Apatite can incorporate sulfur in its reduced form (S2−) when apatite equilibrates with a silicate melt under reducing conditions. Incorporation of sulfate (S6+) has been observed in terrestrial apatite under oxidizing conditions. Thus, it has been suggested that the proportions of S6+/S2− in apatite may record the oxygen fugacity (fO2) during the formation and/or equilibration of apatite grains with a silicate melt in a wide variety of igneous and metamorphic rocks, including from Earth, Mars, the Moon, and in materials from the asteroid belt. Martian rocks, which record fO2 values intermediate between those recorded by rocks from the Moon and Earth, may have apatite that contains only S2− or mixtures of S6+ and S2−. Here, we present new measurements of the oxidation state of sulfur in apatite grains in the basaltic shergottite, Shergotty, which exhibits spectral features consistent with the presence of sulfide (S2−) structurally bound in apatite, and no evidence for the presence of sulfite (S4+) or sulfate (S6+). The presence of sulfide‐only apatite in Shergotty is consistent with other mineralogical records of fO2 in this meteorite, which are calculated from other late‐stage crystallizing phases like Fe‐Ti oxides as well as from early crystallizing phases like clinopyroxene (DEuCpx/melt) of ΔIW + 1.9 to ΔIW + 3.5. At these fO2 values, S is present in silicate melts as only S2−, and this suggests that the oxidation state of sulfur records and preserves the fO2 during the igneous crystallization of apatite reinforcing the idea that sulfur in apatite can be used as an igneous oxybarometer. Plain Language Summary: Apatite is ubiquitous on Earth as well as in different planetary materials. Terrestrial apatite is predominantly sulfate‐rich as Earth is oxidizing. On the Moon, at relatively reducing conditions, apatite can incorporate only sulfide in its structure. Laboratory experiments show mixed species of both sulfide and sulfate in the apatite structure, which can be used as an indicator of oxygen conditions during apatite crystallization. Here, we look at a meteorite from third planetary body, Mars, and confirm the presence of sulfide‐only apatite. This observation strengthens the idea of using sulfur in apatite as a chemical and mineral proxy to determine whether planetary materials are reduced or oxidized. Comparing sulfur in apatite with other proxies can provide perspective on the change (or no change) in reduction and/or oxidation (redox) during later stages of the formation of the volcanic rock. Apatite can also form during metamorphic processes, such as during fluid infiltration into rocks after they are formed. Thus, detailed studies of sulfur in apatite from martian meteorites may place constraints on both the redox conditions during rock formation as well as during hydrothermal alteration on Mars at some time after the volcanic rock was formed. Key Points: We present the first reported data on sulfur speciation in apatite from martian shergottitesSulfur in apatite of Shergotty is present only as sulfide (S2−)The presence of only sulfide places a maximum possible oxygen fugacity of ∆IW = +2.5, consistent with values constrained from other igneous proxies in previous studiesPresence of sulfide needs to be considered while constraining the abundance and behavior of other volatile species using apatite [ABSTRACT FROM AUTHOR] more...

Acid‐sensing ion channels (ASICs) are members of the diverse family of degenerin/epithelial sodium channels (DEG/ENaCs). They perform a wide range of physiological roles in healthy organisms, including in gut function and synaptic transmission, but also play important roles in disease, as acidosis is a hallmark of painful inflammatory and ischaemic conditions. We performed a screen for acid sensitivity on all 30 subunits of the Caenorhabditis elegans DEG/ENaC family using two‐electrode voltage clamp in Xenopus oocytes. We found two groups of acid‐sensitive DEG/ENaCs characterised by being either inhibited or activated by increasing proton concentrations. Three of these acid‐sensitive C. elegans DEG/ENaCs were activated by acidic pH, making them functionally similar to the vertebrate ASICs. We also identified three new members of the acid‐inhibited DEG/ENaC group, giving a total of seven additional acid‐sensitive channels. We observed sensitivity to the anti‐hypertensive drug amiloride as well as modulation by the trace element zinc. Acid‐sensitive DEG/ENaCs were found to be expressed in both neurons and non‐neuronal tissue, highlighting the likely functional diversity of these channels. Our findings provide a framework to exploit the C. elegans channels as models to study the function of these acid‐sensing channels in vivo, as well as to study them as potential targets for anti‐helminthic drugs. Key points: Acidosis plays many roles in healthy physiology, including synaptic transmission and gut function, but is also a key feature of inflammatory pain, ischaemia and many other conditions. Cells monitor acidosis of their surroundings via pH‐sensing channels, including the acid‐sensing ion channels (ASICs). These are members of the degenerin/epithelial sodium channel (DEG/ENaC) family, along with, as the name suggests, vertebrate ENaCs and degenerins of the roundworm Caenorhabditis elegans.By screening all 30 C. elegans DEG/ENaCs for pH dependence, we describe, for the first time, three acid‐activated members, as well as three additional acid‐inhibited channels.We surveyed both groups for sensitivity to amiloride and zinc; like their mammalian counterparts, their currents can be blocked, enhanced or unaffected by these modulators. Likewise, they exhibit diverse ion selectivity.Our findings underline the diversity of acid‐sensitive DEG/ENaCs across species and provide a comparative resource for better understanding the molecular basis of their function. [ABSTRACT FROM AUTHOR] more...

The goals of NASA's Mars 2020 mission include searching for evidence of ancient life on Mars, studying the geology of Jezero crater, understanding Mars' current and past climate, and preparing for human exploration of Mars. During the mission's first science campaign, the Perseverance rover's SHERLOC deep UV Raman and fluorescence instrument collected microscale, two‐dimensional Raman and fluorescence images on 10 natural (unabraded) and abraded targets on two different Jezero crater floor units: Séítah and Máaz. We report SHERLOC Raman measurements collected during the Crater Floor Campaign and discuss their implications regarding the origin and history of Séítah and Máaz. The data support the conclusion that Séítah and Máaz are mineralogically distinct igneous units with complex aqueous alteration histories and suggest that the Jezero crater floor once hosted an environment capable of supporting microbial life and preserving evidence of that life, if it existed. Plain Language Summary: The goals of NASA's Mars 2020 mission include searching for evidence of ancient life on Mars, studying the geology of Jezero crater, understanding Mars' current and past climate, and preparing for human exploration of Mars. During the mission's first science campaign, SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals), one of Perseverance rover's spectroscopic instruments, collected microscale, two‐dimensional images that displayed mineral and organic molecule detections on 10 natural (unabraded) and abraded targets on two different Jezero crater floor geological units: Séítah and Máaz. We report SHERLOC mineral detections made during the Crater Floor Campaign and discuss their implications regarding the origin and history of Séítah and Máaz. The mineral detections support the conclusion that Séítah and Máaz are igneous units with different mineral compositions and distinct histories of alteration by fluids. The detections further suggest that the Jezero crater floor was once home to an environment capable of supporting microbial life and preserving evidence of that life, if it ever existed. Key Points: The floor of the Jezero crater hosts distinct igneous units with differing aqueous alteration historiesSHERLOC Raman mineral class detections indicate that the Jezero crater floor was once a habitable environmentSome Crater Floor Campaign samples may contain salts known to preserve biosignatures in terrestrial analog environments [ABSTRACT FROM AUTHOR] more...

Late maturity alpha-amylase (LMA) and preharvest sprouting (PHS) lead to elevated alpha-amylase in wheat (Triticum aestivum L.) grain. Risk of poor end-product quality due to elevated alpha-amylase is detected in the wheat industry using the Hagberg-Perten falling number (FN) method. In breeding programs, selection for PHS and LMA tolerance requires higher throughput methods requiring a smaller sample size than the 7 g required for the FN method. Specifically, LMA can only be screened only using detection of alpha-amylase activity or protein after cold treatment of individual wheat spikes at a specific stage of grain development resulting in very small samples (=1 g). This study developed and evaluated a high throughput 96-well method for the Phadebas alpha-amylase enzyme assay for small wheat grain samples and compared this method to FN and the Megazyme Alpha-Amylase SD (Sprout Damage) Assay Kit performed on the automated Awareness Technology ChemWell-T Analyzer. In parallel, the efficacy of low-cost small-scale milling methodswas evaluated relative to traditional larger scale mills. The Phadebas enzyme activity was highly reproducible and showed a strong correlation to the SD enzyme assay and FN method regardless of which mill was used to process the grain. The SD assay offers simpler standardization and calculation of enzyme activity, whereas the Phadebas assay offers higher sensitivity and lower expense. Both the 96-well Phadebas and automated Megazyme SD assays are suitable for alpha-amylase detection from small samples, and the use of low-cost coffee grinders to process small samples did not significantly impact assay performance. [ABSTRACT FROM AUTHOR] more...

Objectives: The purpose of this study was to describe the characteristics and age of initiation of nicotine and cannabis use, with a particular focus on the emerging adult period (ages 18–24 years) and concurrent use of nicotine with cannabis. Design: A secondary analysis of Population Assessment of Tobacco and Health (PATH). Sample: 32,078 participants from a nationally representative study of tobacco use and health outcomes. Measurement: Variables of interest included ever use, regular use and age of initiation (first-time use) of nicotine (including tobacco) and/or cannabis and selected demographic factors. Results: Ever-use of nicotine was associated with a 13-fold increase in the likelihood of having ever used cannabis. Among those who reported cannabis use, 96.4% had also used nicotine. While initiation in adolescence was most common, 27.1% of those who use nicotine and 34.9% of those who use cannabis initiated during emerging adulthood. Among regular users of nicotine, 41.5% began regular use in emerging adulthood. Conclusions: These findings underscore the continued susceptibility of emerging adults to initiation of these substances. Co-use of nicotine and cannabis is an understudied phenomenon in emerging adults with significant potential to cause harm and should be a public health priority. [ABSTRACT FROM AUTHOR] more...

Advances in next‐generation sequencing and other high‐throughput technologies have facilitated multiomics research, such as genomics, epigenomics, transcriptomics, proteomics, metabolomics, and phenomics. The resultant emerging multiomics data have brought new challenges as well as opportunities, as seen in the plant and agriculture science domains. We reviewed several bioinformatic and computational methods, models, and platforms, and we have highlighted some of our in‐house developed efforts aimed at multiomics data analysis, integration, and management issues faced by the research community. A case study using multiomics datasets generated from our studies of maize nodal root growth under water deficit stress demonstrates the power of these datasets and some other publicly available tools. This analysis also sheds light on the landscape of such applied bioinformatic tools currently available for plant and crop science studies and introduces emerging trends and how they may affect the future. [ABSTRACT FROM AUTHOR] more...

Meteoritical Bulletin 109 contains the 2790 meteorites approved by the Nomenclature Committee of the Meteoritical Society in 2020. It includes 17 falls (Al Farciya, Auckland, Cavezzo, Flensburg, Gatuto, Kolang, Mahadeva, Matarka, Narashino, Novo Mesto, Oslo, Saint‐Ouen‐en‐Champagne, Santa Filomena, Tarda, Tiros, Wad Lahteyba, Zhob), with 2336 ordinary chondrites, 131 carbonaceous chondrites (including 8 ungrouped ones), 123 HED achondrites, 41 Martian meteorites, 35 lunar meteorites, 23 iron meteorites, 21 ureilites, 17 primitive achondrites, 13 ungrouped achondrites, 12 mesosiderites, 12 Rumuruti chondrites, 9 enstatite chondrites, 8 pallasites, 4 unclassified meteorites (identified at the surface of Mars), 3 enstatite achondrites, 1 angrite, and 1 ungrouped chondrite. One thousand five hundred and forty‐one are from Antarctica, 763 from Africa, 297 from South America, 127 from Asia, 31 from North America, 11 from Europe, 10 from Oceania, 9 from Mars, and 1 from an unknown location. [ABSTRACT FROM AUTHOR] more...

We measured the multispectral images and a hyperspectral profile during the first dissection pass of core 73002, and here, we present preliminary results. Both multispectral images and hyperspectral data show systematic darkening and reddening from bottom to top of the core, indicating an increasing maturity from the subsurface to surface soils. Our estimated FeO and TiO2 abundances are 9 (±1) wt% and 1.8 (±0.5) wt%, and their homogeneous distributions imply no compositional stratigraphy was sampled by core 73002. The in situ regolith reworking depth is about 14 cm as inferred from the optical maturity (OMAT) profile, corresponding to a time range of about 61 million years. Mineralogy and Mg# (molar Mg/[Mg+Fe]) calculated using hyperspectral data and radiative transfer modeling show as expected the core is dominated by plagioclase and low‐Ca pyroxene, and the average Mg# is 61 (±10). Our work shows that spectroscopy has a great potential to be applied in the preliminary examination of future extraterrestrial samples from outside of the glovebox. [ABSTRACT FROM AUTHOR] more...

Meteoritical Bulletin 108 contains 2141 meteorites including 12 falls (Aguas Zarcas, Benenitra, Jalangi, Komaki, Ksar El Goraane, Mhabes el Hamra, Natun Balijan, Oued Sfayat, Shidian, Taqtaq‐e Rasoul, Tocache, Viñales), with 1640 ordinary chondrites, 149 carbonaceous chondrites, 134 HED achondrites, 45 lunar meteorites, 38 ureilites, 27 iron meteorites, 23 Martian meteorites, 22 primitive achondrites, 19 Rumuruti chondrites, 15 mesosiderites, 10 enstatite chondrites, 7 ungrouped achondrites, 4 pallasites, 4 ungrouped chondrites, and 4 angrites. Nine hundred and nine meteorites are from Africa, 747 from Antarctica, 279 from South America, 148 from Asia, 29 from North America, 18 from Oceania, 6 from Europe (including 2 from Russia), and 5 from unknown locations. [ABSTRACT FROM AUTHOR] more...

The composition of a planet's core has important implications for the thermal and magmatic evolution of that planet. Here, we conducted carbon (C) solubility experiments on iron‐silicon (Fe‐Si) metal mixtures (up to 35 wt% [~52 atom%] Si) at 1 GPa and 800–1800°C to determine the carbon concentration at graphite saturation (CCGS) in metallic melt and crystalline metal with varying proportions of Fe and Si to constrain the C content of Mercury's core. Our results, combined with those in the literature, show that composition is the major controlling factor for carbon solubility in Fe‐rich metal with minimal effects from temperature and pressure. Moreover, there is a strong anticorrelation between the abundances of carbon and silicon in iron‐rich metallic systems. Based on the previous estimates of <1–25 wt% Si in Mercury's core, our results indicate that a carbon‐saturated Mercurian core has 0.5–6.4 wt% C, with 6.4 wt% C corresponding to an Si‐free, Fe core and 0.5 wt% C corresponding to an Fe‐rich core with 25 wt% Si. The upper end of estimated FeO abundances in the mantle (up to 2.2 wt%) are consistent with a core that has <1 wt% Si and up to 6.4 wt% C, which would imply that bulk Mercury has a superchondritic Fe/Si ratio. However, the lower end of estimated FeO (≤0.05 wt%) supports CB chondrite‐like bulk compositions of Mercury with core Si abundances in the range of 5–18.5 wt% and C abundances in the range of 0.8–4.0 wt%. Plain Language Summary: The composition of a planet's core can provide clues as to how the planet has changed over time. In this study, we conducted experiments at high pressures and temperatures to investigate potential carbon and silicon abundances in the core of Mercury. We utilized a variety of iron‐silicon metal mixtures (up to 35 wt% silicon) and graphite capsules in order to examine the concentration of carbon in metallic melts and crystalline metals at graphite saturation with the intention of constraining the carbon and silicon content of Mercury's core. Combining the results of this study with those in the literature, we found that composition is the major controlling factor of carbon solubility in silicon‐bearing, iron‐rich metal, with minimal effects from temperature. More importantly, our results showed a strong anticorrelation between the abundances of carbon and silicon in iron‐rich metallic systems. Since Mercury may have formed in a region of the solar system with less oxygen available, it is likely that some silicon partitioned into Mercury's core as silicon becomes more siderophile under reducing conditions. These findings, when combined with other elemental data, can be used to place constraints on the bulk composition of Mercury, which could help to constrain its origin. Key Points: Composition is the main control of carbon concentration at graphite saturation in Fe‐rich metal, with minimal effects from temperature and pressureMercury requires ≥27 wt% Si and ≤0.5 wt% C in its core if it has a bulk EH chondritic compositionMercury requires 5–18.5 wt% Si and 0.8–4.0 wt% C in its core if it has a bulk CB chondritic composition [ABSTRACT FROM AUTHOR] more...

For macromolecular structure determination at synchrotron sources, radiation damage remains a major limiting factor. Estimation of the absorbed dose (J kg−1) during data collection at these sources by programs such as RADDOSE‐3D has allowed direct comparison of radiation damage between experiments carried out with different samples and beam parameters. This has enabled prediction of roughly when radiation damage will manifest so it can potentially be avoided. X‐ray free‐electron lasers (XFELs), which produce intense X‐ray pulses only a few femtoseconds in duration, can be used to generate diffraction patterns before most of the radiation damage processes have occurred and hence hypothetically they enable the determination of damage‐free atomic resolution structures. In spite of this, several experimental and theoretical studies have suggested that structures from XFELs are not always free of radiation damage. There are currently no freely available programs designed to calculate the dose absorbed during XFEL data collection. This article presents an extension to RADDOSE‐3D called RADDOSE‐XFEL, which calculates the time‐resolved dose during XFEL experiments. It is anticipated that RADDOSE‐XFEL could be used to facilitate the study of radiation damage at XFELs and ultimately be used prior to data collection so that experimenters can plan their experiments to avoid radiation damage manifesting in their structures. [ABSTRACT FROM AUTHOR] more...

Native to propionibacteria, the Wood–Werkman cycle enables propionate production via succinate decarboxylation. Current limitations in engineering propionibacteria strains have redirected attention toward the heterologous production in model organisms. Here, we report the functional expression of the Wood–Werkman cycle in Escherichia coli to enable propionate and 1‐propanol production. The initial proof‐of‐concept attempt showed that the cycle can be used for production. However, production levels were low (0.17 mM). In silico optimization of the expression system by operon rearrangement and ribosomal‐binding site tuning improved performance by fivefold. Adaptive laboratory evolution further improved performance redirecting almost 30% of total carbon through the Wood–Werkman cycle, achieving propionate and propanol titers of 9 and 5 mM, respectively. Rational engineering to reduce the generation of byproducts showed that lactate (∆ldhA) and formate (∆pflB) knockout strains exhibit an improved propionate and 1‐propanol production, while the ethanol (∆adhE) knockout strain only showed improved propionate production. [ABSTRACT FROM AUTHOR] more...

Summary: Distyly is an intriguing floral adaptation that increases pollen transfer precision and restricts inbreeding. It has been a model system in evolutionary biology since Darwin. Although the S‐locus determines the long‐ and short‐styled morphs, the genes were unknown in Turnera. We have now identified these genes.We used deletion mapping to identify, and then sequence, BAC clones and genome scaffolds to construct S/s haplotypes. We investigated candidate gene expression, hemizygosity, and used mutants, to explore gene function.The s‐haplotype possessed 21 genes collinear with a region of chromosome 7 of grape. The S‐haplotype possessed three additional genes and two inversions. TsSPH1 was expressed in filaments and anthers, TsYUC6 in anthers and TsBAHD in pistils. Long‐homostyle mutants did not possess TsBAHD and a short‐homostyle mutant did not express TsSPH1.Three hemizygous genes appear to determine S‐morph characteristics in T. subulata. Hemizygosity is common to all distylous species investigated, yet the genes differ. The pistil candidate gene, TsBAHD, differs from that of Primula, but both may inactivate brassinosteroids causing short styles. TsYUC6 is involved in auxin synthesis and likely determines pollen characteristics. TsSPH1 is likely involved in filament elongation. We propose an incompatibility mechanism involving TsYUC6 and TsBAHD. [ABSTRACT FROM AUTHOR] more...

Electronic nicotine delivery systems (ENDS), which includes e‐cigarettes (ECIGs), are a rapidly‐expanding class of products that heat a liquid (which may or may not contain nicotine) to produce an aerosol. The variation of ECIG components is extensive as are their effects on users. Epidemiological data show that while both adults and youth use ECIGs, use among youth has increased dramatically in recent years. Other epidemiological data show that women of reproductive age and some pregnant women are also using ECIGs. The goal of this article is to provide readers with background information about ECIGs, with a focus on recent findings about ECIG use in pregnancy and potential implications. Among pregnant women, correlates of ECIG use include current cigarette smoking, among other factors. Regarding pregnant women's perceptions of ECIG use in pregnancy, two themes emerge from the literature: many pregnant women perceive ECIGs to be safer than conventional cigarettes, and that ECIGs can aid with smoking cessation. In contrast to these perceptions, there is little concrete evidence that ECIGs help smokers quit. In addition, there are concerns about ECIG nicotine and other toxicant delivery. Nicotine is a toxicant of particular concern for pregnant women, as nicotine is known to harm a developing fetus. There are many limitations to existing research, and the literature is scant in this area. Further, new "pod mod"‐style ECIGs such as JUUL present new challenges. Overall, with limited evidence of their effectiveness, and concerns about developmental toxicology, the authors do not recommend that pregnant women use ECIGs. [ABSTRACT FROM AUTHOR] more...

This document contains suggestions for best practices by authors who refer to meteorites in publications. It can also be taken as a guide for publishers in establishing guidelines for authors. The following best practices are recommended in addition to acknowledging the loaning institution or loaning individual (unless required otherwise). The main motivations are to: help ensure that research on meteorites is reproducible, prevent confusion in the literature, and enhance tracking of specimens and related data. [ABSTRACT FROM AUTHOR] more...

We present petrologic and isotopic data on Northwest Africa (NWA) 4799, NWA 7809, NWA 7214, and NWA 11071 meteorites, which were previously classified as aubrites. These four meteorites contain between 31 and 56 vol% of equigranular, nearly endmember enstatite, Fe,Ni metal, plagioclase, terrestrial alteration products, and sulfides, such as troilite, niningerite, daubréelite, oldhamite, and caswellsilverite. The equigranular texture of the enstatite and the presence of the metal surrounding enstatite indicate that these rocks were not formed through igneous processes like the aubrites, but rather by impact processes. In addition, the presence of pre‐terrestrially weathered metal (7.1–14 vol%), undifferentiated modal abundances compared to enstatite chondrites, presence of graphite, absence of diopside and forsterite, low Ti in troilite, and high Si in Fe,Ni metals suggest that these rocks formed through impact melting on chondritic and not aubritic parent bodies. Formation of these meteorites on a parent body with similar properties to the EHa enstatite chondrite parent body is suggested by their mineralogy. These parent bodies have undergone impact events from at least 4.5 Ga (NWA 11071) until at least 4.2 Ga (NWA 4799) according to 39Ar‐40Ar ages, indicating that this region of the solar system was heavily bombarded early in its history. By comparing NWA enstatite chondrite impact melts to Mercury, we infer that they represent imperfect petrological analogs to this planet given their high metal abundances, but they could represent important geochemical analogs for the behavior and geochemical affinities of elements on Mercury. Furthermore, the enstatite chondrite impact melts represent an important petrological analog for understanding high‐temperature processes and impact processes on Mercury, due to their similar mineralogies, Fe‐metal‐rich and FeO‐poor silicate abundances, and low oxygen fugacity. [ABSTRACT FROM AUTHOR] more...

Abstract: Dietary changes linked to the availability of anthropogenic food resources can have complex implications for species and ecosystems, especially when species are in decline. Here, we use recently developed primers targeting the ITS2 region of plants to characterize diet from faecal samples of four UK columbids, with particular focus on the European turtle dove (Streptopelia turtur), a rapidly declining obligate granivore. We examine dietary overlap between species (potential competition), associations with body condition in turtle doves and spatiotemporal variation in diet. We identified 143 taxonomic units, of which we classified 55% to species, another 34% to genus and the remaining 11% to family. We found significant dietary overlap between all columbid species, with the highest between turtle doves and stock doves (Columba oenas), then between turtle doves and woodpigeons (Columba palumbus). The lowest overlap was between woodpigeons and collared doves (Streptopelia decaocto). We show considerable change in columbid diets compared to previous studies, probably reflecting opportunistic foraging behaviour by columbids within a highly anthropogenically modified landscape, although our data for nonturtle doves should be considered preliminary. Nestling turtle doves in better condition had a higher dietary proportion of taxonomic units from natural arable plant species and a lower proportion of taxonomic units from anthropogenic food resources such as garden bird seed mixes and brassicas. This suggests that breeding ground conservation strategies for turtle doves should include provision of anthropogenic seeds for adults early in the breeding season, coupled with habitat rich in accessible seeds from arable plants once chicks have hatched. [ABSTRACT FROM AUTHOR] more...

Abstract: Curation and preparation of samples for chemical analysis can occasionally lead to significant contamination. This issue is of concern in the study of lunar samples, especially those from the Apollo sample collection, where available masses are finite. Here we present compositional data for stainless steels that have commonly been used in the processing of Apollo lunar samples at NASA Johnson Space Center, including a chisel and a vessel typically used to transfer Apollo samples to principal investigators. The Type 304 stainless steels are Cr‐rich, with high concentrations of Mn (4000–18,000 μg g−1), Cu (1000–22,900 μg g−1), Mo (1030–1120 μg g−1), and W (72–193 μg g−1). They have elevated highly siderophile element (HSE) concentrations (up to 92 ng g−1 Os), 187Os/188Os ranging from 0.1310 to 0.1336, and negligible lithophile element abundances. We find that, while metal contamination is possible, significant (≫0.01% by mass) addition of stainless steel is required to strongly affect the composition of the HSE, W, Mo, Cr, or Cu for most Apollo lunar samples. Nonetheless, careful appraisal on a case‐by‐case basis should take place to ensure contamination introduced through sample processing during curation is at acceptably low levels. A survey of lunar mare basalts and crustal rocks indicates that metal contamination plays a negligible role in the compositional variability of the HSE and W compositions preserved in these samples. Further work to constrain contamination for other properties of Apollo samples is required (e.g., organics, microbes, water, noble gases, and magnetics), but the effect of metal contamination can be well‐constrained for the Apollo lunar collection. [ABSTRACT FROM AUTHOR] more...

Background: When developing walking programmes for improving health in adults with Down syndrome (DS), physical activity professionals are in need of an equation for predicting energy expenditure. We therefore developed and cross‐validated an equation for predicting the rate of oxygen uptake (VO2; an index of energy expenditure) for adults with and without DS. Method: A total of 469 VO2 observations during walking across different speeds were available from 54 adults with DS and 61 adults without DS. Results: Significant predictors of VO2 were speed, speed square, group and group‐by‐speed interaction. Separate models for each group showed that speed and its square significantly predicted VO2. Absolute per cent error was small and did not differ between groups. Conclusion: Adults with DS have different VO2 response to walking speed from persons without DS. VO2 is predicted from speed with acceptable accuracy for persons with DS. [ABSTRACT FROM AUTHOR] more...

Data from the Gamma-Ray Spectrometer (GRS) that flew on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft indicate that the O/Si weight ratio of Mercury's surface is 1.2 ± 0.1. This value is lower than any other celestial surface that has been measured by GRS and suggests that 12-20% of the surface materials on Mercury are composed of Si-rich, Si-Fe alloys. The origin of the metal is best explained by a combination of space weathering and graphite-induced smelting. The smelting process would have been facilitated by interaction of graphite with boninitic and komatiitic parental liquids. Graphite entrained at depth would have reacted with FeO components dissolved in silicate melt, resulting in the production of up to 0.4-0.9 wt % CO from the reduction of FeO to Fe0-CO production that could have facilitated explosive volcanic processes on Mercury. Once the graphite-entrained magmas erupted, the tenuous atmosphere on Mercury prevented the buildup of CO over the lavas. The partial pressure of CO would have been sufficiently low to facilitate reaction between graphite and SiO2 components in silicate melts to produce CO and metallic Si. Although exotic, Si-rich metal as a primary smelting product is hypothesized on Mercury for three primary reasons: (1) low FeO abundances of parental magmas, (2) elevated abundances of graphite in the crust and regolith, and (3) the presence of only a tenuous atmosphere at the surface of the planet within the 3.5-4.1 Ga timespan over which the planet was resurfaced through volcanic processes. [ABSTRACT FROM AUTHOR] more...

Extant measures of well-being, guided by western European values and beliefs, reveal a scientific commitment to develop and test indices to monitor the social, psychological, familial, and economic status of populations. The limitations of these measures to ethnic populations are addressed in this study. Relational Well-being ( RWB II), an indigenous, culture-based 14-item measure rooted in beliefs and values emphasizing family, ancestors, culture, and harmony with nature, was developed and tested with a sample (N = 810) of indigenous Hawaiians in Hawaii. Exploratory factor analysis (n = 408), confirmatory factor analysis (n = 402), test of invariance, and tests of reliability and validity confirmed the psychometric quality of RWB II. The applicability of the composite index of Relational Well-being II as well as its six underlying factors (Resilience, Community Involvement, Financial Stability, Cultural Practice, Family Commitment, and Health Care) to family theory of resilience, research, and education are discussed. [ABSTRACT FROM AUTHOR] more...

An introduction is presented in which the editors discuss several topics appearing elsewhere in the issue, including information on multiethnic families in the U.S., racial socialization and multiracial adolescents, and research on the well-being of monoracial kindergarten children. more...

This review is intended to summarize the current observations of reduced carbon in Martian meteorites, differentiating between terrestrial contamination and carbon that is indigenous to Mars. Indeed, the identification of Martian organic matter is among the highest priority targets for robotic spacecraft missions in the next decade, including the Mars Science Laboratory and Mars 2020. Organic carbon compounds are essential building blocks of terrestrial life, so the occurrence and origin (biotic or abiotic) of organic compounds on Mars is of great significance; however, not all forms of reduced carbon are conducive to biological systems. This paper discusses the significance of reduced organic carbon (including methane) in Martian geological and astrobiological systems. Specifically, it summarizes current thinking on the nature, sources, and sinks of Martian organic carbon, a key component to Martian habitability. Based on this compilation, reduced organic carbon on Mars, including detections of methane in the Martian atmosphere, is best described through a combination of abiotic organic synthesis on Mars and infall of extraterrestrial carbonaceous material. Although conclusive signs of Martian life have yet to be revealed, we have developed a strategy for life detection on Mars that can be utilized in future life-detection studies. [ABSTRACT FROM AUTHOR] more...

We conducted a petrologic study of apatite within 12 Martian meteorites, including 11 shergottites and one basaltic regolith breccia. These data were combined with previously published data to gain a better understanding of the abundance and distribution of volatiles in the Martian interior. Apatites in individual Martian meteorites span a wide range of compositions, indicating they did not form by equilibrium crystallization. In fact, the intrasample variation in apatite is best described by either fractional crystallization or crustal contamination with a Cl-rich crustal component. We determined that most Martian meteorites investigated here have been affected by crustal contamination and hence cannot be used to estimate volatile abundances of the Martian mantle. Using the subset of samples that did not exhibit crustal contamination, we determined that the enriched shergottite source has 36-73 ppm H2O and the depleted source has 14-23 ppm H2O. This result is consistent with other observed geochemical differences between enriched and depleted shergottites and supports the idea that there are at least two geochemically distinct reservoirs in the Martian mantle. We also estimated the H2O, Cl, and F content of the Martian crust using known crust-mantle distributions for incompatible lithophile elements. We determined that the bulk Martian crust has ~1410 ppm H2O, 450 ppm Cl, and 106 ppm F, and Cl and H2O are preferentially distributed toward the Martian surface. The estimate of crustal H2O results in a global equivalent surface layer ( GEL) of ~229 m, which can account for at least some of the surface features on Mars attributed to flowing water and may be sufficient to support the past presence of a shallow sea on Mars' surface. [ABSTRACT FROM AUTHOR] more...

Previous estimates of the volatile contents of Martian basalts, and hence their source regions, ranged from nearly volatile-free through estimates similar to those found in terrestrial subduction zones. Here, we use the bulk chemistry of Martian meteorites, along with Martian apatite and amphibole chemistry, to constrain the volatile contents of the Martian interior. Our estimates show that the volatile content of the source region for the Martian meteorites is similar to the terrestrial Mid-Ocean-Ridge Mantle source. Chlorine is enriched compared with the depleted terrestrial mantle but is similar to the terrestrial enriched source region; fluorine is similar to the terrestrial primitive mantle; and water is consistent with the terrestrial mantle. Our results show that Martian magmas were not volatile saturated; had water/chlorine and water/fluorine ratios ~0.4-18; and are most similar, in terms of volatiles, to terrestrial MORBs. Presumably, there are variations in volatile content in the Martian interior as suggested by apatite compositions, but more bulk chemical data, especially for fluorine and water, are required to investigate these variations. Finally, the Noachian Martian interior, as exemplified by surface basalts and NWA 7034, may have had higher volatile contents. [ABSTRACT FROM AUTHOR] more...

The Martian meteorites record a wide diversity of environments, processes, and ages. Much work has been done to decipher potential mantle sources for Martian magmas and their interactions with crustal and surface environments. Chlorine isotopes provide a unique opportunity to assess interactions between Martian mantle-derived magmas and the crust. We have measured the Cl-isotopic composition of 17 samples that span the range of known ages, Martian environments, and mantle reservoirs. The 37Cl of the Martian mantle, as represented by the olivine-phyric shergottites, NWA 2737 (chassignite), and Shergotty (basaltic shergottite), has a low value of approximately −3.8‰. This value is lower than that of all other planetary bodies measured thus far. The Martian crust, as represented by regolith breccia NWA 7034, is variably enriched in the heavy isotope of Cl. This enrichment is reflective of preferential loss of 35Cl to space. Most basaltic shergottites (less Shergotty), nakhlites, Chassigny, and Allan Hills 84001 lie on a continuum between the Martian mantle and crust. This intermediate range is explained by mechanical mixing through impact, fluid interaction, and assimilation-fractional crystallization. [ABSTRACT FROM AUTHOR] more...

Multiple observations from missions to Mars have revealed compelling evidence for a volatile-rich Martian crust. A leading theory contends that eruption of basaltic magmas was the ultimate mechanism of transfer of volatiles from the mantle toward the surface after an initial outgassing related to the crystallization of a magma ocean. However, the concentrations of volatile species in ascending magmas and in their mantle source regions are highly uncertain. This work and this special issue of Meteoritics & Planetary Science summarize the key findings of the workshop on Volatiles in the Martian Interior (Nov. 3-4, 2014), the primary open questions related to volatiles in Martian magmas and their source regions, and the suggestions of the community at the workshop to address these open questions. [ABSTRACT FROM AUTHOR] more...

Resting blood pressure (BP) shows a negative relationship with pain sensitivity (BP-related hypoalgesia). In chronic pain conditions, this relationship is inverted. The precise mechanisms responsible for the inversion are unknown. Using a tonic pain protocol, we report findings closely resembling this inversion in healthy participants. Resting BP and state measures of anxiety and mood were assessed from 33 participants (21 female). Participants then immersed their dominant hand in painfully hot water (47 °C) for five trials of 1-min duration, with 30-s intertrial intervals. Throughout the trials, participants continually registered their pain. After a 35-min intermission, the trial sequence was repeated. A disassociation of the negative relationship of resting systolic BP (as per Trial 1) was found using hierarchical linear modeling ( p < .001, R2 = .07). The disassociation unfolds over each consecutive trial, with an increasingly positive relationship. In Sequence 2, the initially negative relationship is almost completely absent. Furthermore, the association of BP and pain was found to be moderated by anxiety, such that only persons with low anxiety exhibited BP hypoalgesia. Our findings expand the existing literature by incorporating anxiety as a moderator of BP hypoalgesia. Furthermore, the protocol emulates the changing relationship between BP and pain observed in chronic pain patients. The protocol has potential as a model for chronic pain; however, future research should determine if similar physiological systems are involved. The finding holds potential diagnostic or prognostic relevance for certain clinical pain conditions, especially those involving dysfunction of the descending modulation of pain. [ABSTRACT FROM AUTHOR] more...

The purpose of this study was to examine the relationships among subclinical PTSD symptoms, blood pressure, and several variables linked to both frank PTSD and the basic psychobiological adaptation to stress. The authors recruited a sample of 91 healthy, young men and women between 18 and 35 years. We examined links among subclinical posttraumatic stress disorder symptoms, blood pressure, sleep quality, and hostility. Posttraumatic stress disorder symptoms were associated with poorer sleep quality and higher hostility scores in both women and men. In men, PTSD symptoms were also associated with elevated resting diastolic blood pressure, and sex was an important moderator of that relationship. Moreover, sleep quality and hostility are substantive mediators of the relationship between diastolic blood pressure and PTSD. Behavioral interventions designed to increase sleep quality and restructure hostile attitudes could potentially serve as preventive interventions for PTSD and the underlying cardiovascular comorbidities in young adults. [ABSTRACT FROM AUTHOR] more...

The bulk matrix domain of the Martian breccia NWA 7034 was examined petrographically and isotopically to better understand the provenance and age of the source material that make up the breccia. Both 147Sm-143Nd and 146Sm-142Nd age results for mineral separates from the bulk matrix portion of breccia NWA 7034 suggest that various lithological components in the breccia probably formed contemporaneously ~4.44 Ga ago. This old age is in excellent agreement with the upper intersection ages (4.35-4.45 Ga) for U-Pb discordia and also concordia defined by zircon and baddeleyite grains in matrix and igneous-textured clasts. Consequently, we confirm an ancient age for the igneous components that make up the NWA 7034 breccia. Substantial disturbance in the Rb-Sr system was detected, and no age significance could be gleaned from our Rb-Sr data. The disturbance to the Rb-Sr system may be due to a thermal event recorded by bulk-rock K-Ar ages of 1.56 Ga and U-Pb ages of phosphates at about 1.35-1.5 Ga, which suggest partial resetting from an unknown thermal event(s), possibly accompanying breccia formation. The NWA 7034 bulk rock is LREE enriched and similar to KREEP-rich lunar rocks, which indicates that the earliest Martian crust was geochemically enriched. This enrichment supports the idea that the crust is one of the enriched geochemical reservoirs on Mars that have been detected in studies of other Martian meteorites. [ABSTRACT FROM AUTHOR] more...

Merrillite is a ubiquitous accessory phase in a variety of Martian meteorite lithologies. The Martian merrillites exhibit a positive correlation between Mg# and Na and a negative correlation between Mg# and both Mn and vacancies in the octahedral Na-site. Their REE patterns are varied and range from LREE-depleted to LREE-enriched. The dominant cation substitutions in the Martian merrillites are Fe2+ VI Mg-site⇔Mg2+ VI Mg-site and Ca2+ VI Na-site + □VI Na-site⇔2Na+ VI Na-site. The REE substitution into the 8-fold coordinated Ca-site is accommodated by the coupled substitution Ca VIII Ca-site + (Na) VI Na-site ⇔(Y3+ + REE3+) VIII Ca-site + □ VI Na-site. The REE substitution is significantly more prevalent in lunar merrillite and can be used as a 'fingerprint' to distinguish lunar from Martian meteorites. The substitution of OH− (whitlockite) and/or F− (bobdownsite) for O2− on one of the phosphate tetrahedrons appears to be rather insignificant. The correlations among Na, Mg#, Mn, and Na-site vacancies are linked to the premerrillite crystallization history of the melt and the crystal chemical behavior of the Mg- and Na-sites. The former reflects the sequence and extent of plagioclase and pyroxene crystallization. The differences in REE pattern shapes among the merrillites reflect source regions for the Martian basalts and the shapes are not greatly perturbed by the crystallization history. The occurrence of merrillite does not imply low-volatile component in the Martian magmas. However, the low whitlockite and bobdownsite contents suggest that these samples were not altered by hydrothermal fluids and therefore not reset owing to aqueous fluid interactions. Consequently, the young ages of the shergottites are probably true igneous crystallization ages. [ABSTRACT FROM AUTHOR] more...

The study of resilient families, or the search for characteristics, dimensions, and properties of families which help families to be resistant to disruption in the face of change and adaptive in the face of crisis situations, is a natural and predictable development in the evolution of family science. Current findings from the studies conducted on resilient families are reviewed and summarized with an emphasis on three emerging issues. The importance of social class and ethnicity is accentuated in a review of current studies conducted on military families. Deterrents to and the need for more research on resilient families are discussed in relationship to the value of prevention oriented family programs. [ABSTRACT FROM AUTHOR] more...

Are there coping patterns parents use to manage family life and health successfully when a child member has a chronic illness? In the present study, data were collected on 100 families who have a child with cystic fibrosis. By factor analyzing scaled responses to behavior items on the Coping Health Inventory for Parents (CHIP), three parental coping patterns emerged: (a) maintaining family integration, cooperation, and an optimistic definition of the situation; (b) maintaining social support, self-esteem, and psychological stability; and (c) understanding the medical situation through communication with other parents and consultation with the medical staff. These patterns were validated against criterion measures of improvements in the child's health and adaptive family-life dimensions of cohesiveness, expressiveness, conflict reduction, organization, and control. The findings have implications for present strategies of health-care delivery and for health-care professionals seeking to facilitate family adaptation to the stresses of chronic illness. [ABSTRACT FROM AUTHOR] more...

An unusual behavioral and cardiovascular reaction was observed during opioid blockade with naltrexone in a 32-year-old male who met DSM III-R criteria for post-traumatic stress disorder (PTSD). As part of an ongoing placebo-controlled investigation of the effects of naltrexone on laboratory and ambulatory blood pressure reactivity, this participant reported experiencing feelings of rage, explosive behavior, and other unpleasant symptoms. When compared to all other subjects (N = 24), this individual showed significantly greater effects of naltrexone on blood pressure reactivity during the laboratory stressor. His ambulatory blood pressures, when compared to placebo, were significantly increased during the 24-hr period following naltrexone. The unusual behavioral and cardiovascular responses following ingestion of naltrexone suggest an important role for endogenous opioids in adjustment to stress in this case of PTSD. [ABSTRACT FROM AUTHOR] more...