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Purpose This research paper aims to provide conceptual clarity for marketplaces within the lateral exchange market framework. The advances in digital technologies have been critical to the growth of new marketplaces and forms of exchange. While there are many different names and manifestations of these marketplaces, the common thread is they all require digital platform intermediation. These marketplaces are referred to by a variety of names and characteristics, and a clear consensus has yet to be achieved. Design/methodology/approach This research uses a conceptual approach rooted in the marketing literature. Findings This study differentiates and defines the sharing economy, collaborative consumption and access-based consumption, as well as introduces the concept of liquid ownership – all under the LEM framework. Defining characteristics for each marketplace are noted to present a consistent classification of the focal concepts for the advancement of research and theory. Research limitations/implications As the number and types of lateral exchange marketplaces continue to grow, researchers need to have a clear delineation of the concepts. This research seeks to provide clarity on the disparate literature streams and introduces the concept of liquid ownership to allow for the advancement of research and theory surrounding these forms of consumption. Practical implications Understanding existing marketplaces is vital for online platforms as they develop new offerings and differentiate themselves in the marketplace. Additionally, opportunities for traditional businesses abound as they pursue new market opportunities and adapt to changing technologies. Thus, research questions concerning consumers and platform managers are presented. Originality/value This research contributes conceptual clarity on elements commonly associated with the sharing economy while expanding it to include elements found in LEMs. The concept of liquid ownership is also presented to reflect the evolving consumption landscape. Research opportunities and questions are provided to guide future scholarly work.

To identify plasma proteins that mirror current and predict future remodeling after myocardial infarction (MI), we retrospectively interrogated plasma proteomes of day (D)0 control (n = 16) and D3 MI (n = 15) from C57BL/6 J mice (20 ± 1 months). A total of 165 unique proteins were correlated with cardiac physiology variables. We prospectively tested the hypothesis that candidates identified retrospectively would predict cardiac physiology at an extended timepoint (D7 MI) in a second cohort of mice (n = 4 ± 1 months). We also examined human plasma from healthy controls (n = 18) and patients 48 h after presentation for MI (n = 41). Retrospectively, we identified 5 strong reflectors of remodeling (all r ≥ 0.60 and p Graphical Abstract

High systolic blood pressure (SBP) is a major risk factor for ischemic heart disease (IHD), the leading cause of death worldwide. Using data from published observational studies and controlled trials, we estimated the mean SBP–IHD dose–response function and burden of proof risk function (BPRF), and we calculated a risk outcome score (ROS) and corresponding star rating (one to five). We found a very strong, significant harmful effect of SBP on IHD, with a mean risk—relative to that at 100 mm Hg SBP—of 1.39 (95% uncertainty interval including between-study heterogeneity 1.34–1.44) at 120 mm Hg, 1.81 (1.70–1.93) at 130 mm Hg and 4.48 (3.81–5.26) at 165 mm Hg. The conservative BPRF measure indicated that SBP exposure between 107.5 and 165.0 mm Hg raised risk by 101.36% on average, yielding a ROS of 0.70 and star rating of five. Our analysis shows that IHD risk was already increasing at 120 mm Hg SBP, rising steadily up to 165 mm Hg and increasing less steeply above that point. Our study endorses the need to prioritize and strengthen strategies for screening, to raise awareness of the need for timely diagnosis and treatment of hypertension and to increase the resources allocated for understanding primordial prevention of elevated blood pressure.

Low vitamin A (VA) status is common among lactating women in low-income countries. Lactation has substantial effects on mother's metabolism and VA is required in multiple biological processes, including growth, vision, immunity, and reproduction. The objective of this pilot study was to use metabolomics profiling to conduct a broad, exploratory assessment of differences in plasma metabolites associated with low VA status versus VA adequacy in lactating women. Plasma samples from lactating women who participated in a survey in Samar, Philippines, were selected from a cross-sectional study based on plasma retinol concentrations indicating low (VA-; n = 5) or adequate (VA+; n = 5) VA status (plasma retinol0.8 or1.05 µmol/L). The plasma results collected from 6 metabolomics assays (oxylipins, endocannabinoids, bile acids, primary metabolomics, biogenic amines, and lipidomics) were compared by group using liquid chromatography mass spectrometry. Twenty-eight metabolites were altered in the VA- versus VA+ status groups, with 24 being lipid mediators (P.05). These lipid mediators included lower concentrations of arachidonic acid- and eicosapentaenoic acid-derived oxylipins, as well as lysophospholipids and sphingolipids, in the VA- group (P.05). Chemical similarity enrichment analysis identified hydroxy-eicosatetraenoic acids, hydroxy-eicosapentaenoic acids, and dihydroxy-eicosatetraenoic acids as significantly altered oxylipin clusters (P.0001, false discovery rate [FDR] P.0001), as well as sphingomyelins, saturated lysophosphatidylcholines, phosphatidylcholines, and phosphatidylethanolamines (P.001, FDR P.01). The multiassay nutritional metabolomics profiling of low VA status compared with adequacy in lactating women was characterized by reduced lipid mediator concentrations. Future studies with stronger study designs and larger sample size are needed to confirm and validate these preliminary results.

Life expectancy (LE) differences within and between states by race/ethnicity have not been examined.To estimate LE for selected race/ethnicity groups in states from 1990 to 2019.Cross-sectional time-series analysis.United States.Deidentified death records and Census data were used to construct regression models with smoothed time series of mortality from 1990 to 2019.LE at birth, by sex and year, for subgroups of people reporting Hispanic, non-Hispanic Black, or non-Hispanic White race/ethnicity.Disparities in LE across states were 8.0 years for females and 12.2 years for males in 1990 and 7.9 years for females and 7.8 years for males in 2019. When race/ethnicity groups were accounted for, disparities across states were 20.7 years for females and 24.5 years for males in 1990, decreasing to 18.5 years for females and 23.7 years for males in 2019. Disparities across states increased within each race/ethnicity group between 1990 and 2019, with the largest increase for non-Hispanic White males and the smallest for Hispanic females. The disparity between race/ethnicity groups within states decreased for most of the 23 states with estimates for all 3 groups but increased for females in 7 states and males in 5 states.Because of small sample size, LE was not estimated for 37 of 153 state-race/ethnicity groups.Disparity in LE across states was greater when race/ethnicity groups were considered. Disparities across all state-race/ethnicity groups in general have decreased over the past 3 decades. Within each race/ethnicity group, disparities across states have increased. Although racial/ethnic disparities decreased in most of the 23 states for which LE was estimated for all 3 groups, they increased for females in 7 states and males in 5 states.National Heart, Lung, and Blood Institute.

The recent successful flight demonstration of the Mars 2020 helicopter, Ingenuity, has opened doors for future Mars mission concepts that exploit modern technology, and promising investigations include low altitude magnetic field surveys. The martian crustal magnetic field has been studied extensively from orbit and those data sets have allowed global studies of the magnetic field and resulted in a range of models for the crustal magnetic field which however lack short wavelength information that is not resolvable from orbital altitudes. The InSight lander and the Chinese Zhurong missions have recently acquired magnetic measurements of the local field at their respective landing sites. However, to-date no measurements at scales in between those of local surface and global orbital data have been collected. Such measurements are key to understanding near-surface magnetizations, the processes by which they were acquired, and their interaction with magnetic fields generated above the planet’s surface. Here, we investigate data sets that a future helicopter-based magnetometer might be able to provide.We construct forward models that resemble a range of plausible subsurface geological structures that allow us to experiment with survey design, e.g., the value of multiple measurement tracks horizontally and/or vertically and their trade-offs with regional data coverage. We simulate vector magnetic field data collected by a helicopter for different geological scenarios and aim to recover our model via an inverse problem. Because such inverse problems are inherently non-unique, we investigate several approaches to find solutions, including different types of regularization, as well as modification of the model parameterization. As one example, we investigate recovery of a magnetization signature associated with a small (~200 m diameter) crater, from a few (e.g., 3) helicopter tracks over the crater. We show that smooth and sparse inversion solutions result in detection of the signal, with improved localization of the structure in the latter case. Parameterized solutions improve upon sparse solutions, but require some prior knowledge, or assumption, of the geometry (in this case a magnetized half sphere) of the source.Our investigation allows us to assess the capabilities of helicopter-based magnetic field studies in addressing some of the fundamental open questions in the field. These kinds of considerations will greatly aid in preparing for and designing future missions, optimizing their science return and demonstrating their scientific value.

Purpose This study aims to identify the impact that Machiavellianism, narcissism and psychopathy tendencies have on avoidance and revenge-seeking after a service failure. The research examines the role that negative affect and desire for revenge play in aggressive behaviors by consumers. Design/methodology/approach The study uses a survey research methodology. The measurement model is validated using CFA, and hypotheses are tested using structural equation modeling. The mediated and serially mediated relationships are calculated using the bootstrap method by creating estimands to test the effects. Findings Machiavellianism is less likely to drive avoidance and negative affect, reducing desire for revenge, negative word of mouth and vindictive complaining. Those with narcissism tendencies are likely to develop a negative affect and a corresponding desire for revenge after the failure only if negative affect is developed. Consumers who exhibit psychopathy tendencies are likely to seek out revenge directly. Practical implications Each Dark Triad tendency influences consumer avoidance and revenge-seeking in different ways when a consumer’s goals are impeded. Companies can focus on service recoveries differently based on the types of tendencies of consumers engaging in avoidance and revenge-seeking. Originality/value The individual paths from Machiavellianism, narcissism and psychopathy tendencies to avoidance and revenge-seeking are developed and analyzed. Further distinctions between each Dark Triad tendency aids service providers in addressing and preparing for these consumer behaviors.

Direct reaction of precursors with the products of detonation remains an underexplored area in the ever-growing body of detonation synthesis literature. This study demonstrated the synthesis of silicon carbide during detonation by reaction of elemental silicon with carbon products formed from detonation of RDX/TNT mixtures. Continuum scale simulation of the detonation showed that energy transfer by the detonation wave was completed within 2–9 μs depending on location of measurement within the detonating explosive charge. The simulated environment in the detonation product flow beyond the Chapman-Jouguet condition where pressure approaches 27 GPa and temperatures reach 3300 K was thermodynamically suitable for cubic silicon carbide formation. Carbon and added elemental silicon in the detonation products remained chemically reactive up to 500 ns after the detonation wave passage, which indicated that the carbon-containing products of detonation could participate in silicon carbide synthesis provided sufficient carbon-silicon interaction. Controlled detonation of an RDX/TNT charge loaded with 3.2 wt% elemental silicon conducted in argon environment lead to formation of ∼3.1 wt% β-SiC in the condensed detonation products. Other condensed detonation products included primarily amorphous silica and carbon in addition to residual silicon. These results show that the energized detonation products of conventional high explosives can be used as precursors in detonation synthesis of ceramic nanomaterials.

High yielding dairy cattle are typically fed a total mixed ration (TMR) to meet their energy requirements. However, inadequate mixing can lead to feed selection and dietary imbalance, negatively affecting rumen metabolism and the microbiome. To investigate the effect of TMR mixing, four dairy cows were fed a partial mixed ration with dietary concentrates (4 kg/cow/day) added separately in even and uneven patterns of allocation (CA) with a Saccharomyces cerevisiae yeast supplement (YS) (1 g/cow/day). Rumen digesta samples were taken to measure microbial metabolism and microbiome using16S rRNA amplicon sequencing. No effect of CA on rumen metabolism was detected. YS inclusion tended to increase rumen pH (P= 0.088) reduce total VFA concentration (P= 0.033) and propionate concentration (P= 0.016). Clustering of the rumen microbiome was observed with YS supplementation, driven by a decrease in abundance of Gammaproteobacteria and Prevotellaceae OTUs respectively and an increase of a Christensenellaceae OTU. Pattern of concentrate allocation had no detectable effect on alpha diversity or Bray Curtis dissimilarity. However, reduction in relative abundance of a Prevotellaceae OTU biomarker was associated with uneven pattern of concentrate allocation. Pattern of concentrate allocation and YS supplementation did not adversely affect milk yield or composition.

The labyrinth of the vertebrate inner ear is a sensory system that governs the perception of head rotations. Central hypotheses predict that labyrinth shape and size are related to ecological adaptations, but this is under debate and has rarely been tested outside of mammals. We analyze the evolution of labyrinth morphology and its ecological drivers in living and fossil turtles, an understudied group that underwent multiple locomotory transitions during 230 million years of evolution. We show that turtles have unexpectedly large labyrinths that evolved during the origin of aquatic habits. Turtle labyrinths are relatively larger than those of mammals, and comparable to many birds, undermining the hypothesis that labyrinth size correlates directly with agility across vertebrates. We also find that labyrinth shape variation does not correlate with ecology in turtles, undermining the widespread expectation that reptilian labyrinth shapes convey behavioral signal, and demonstrating the importance of understudied groups, like turtles.

White‐nose syndrome (WNS) is a disease caused by the fungus Pseudogymnoascus destructans which has resulted in the deaths of millions of bats across eastern North America. To date, hibernacula counts have been the predominant means of tracking the spread and impact of this disease on bat populations. However, an understanding of the impacts of WNS on demographic parameters outside the winter season is critical to conservation and recovery of bat populations impacted by this disease. We used long‐term monitoring data to examine WNS‐related impacts to summer populations in West Virginia, where WNS has been documented since 2009. Using capture data from 290 mist‐net sites surveyed from 2003 to 2019 on the Monongahela National Forest, we estimated temporal patterns in presence and relative abundance for each bat species. For species that exhibited a population‐level response to WNS, we investigated post‐WNS changes in adult female reproductive state and body mass. Myotis lucifugus (little brown bat), M. septentrionalis (northern long‐eared bat), and Perimyotis subflavus (tri‐colored bat) all showed significant decreases in presence and relative abundance during and following the introduction of WNS, while Eptesicus fuscus (big brown bat) and Lasiurus borealis (eastern red bat) responded positively during the WNS invasion. Probability of being reproductively active was not significantly different for any species, though a shift to earlier reproduction was estimated for E. fuscus and M. septentrionalis. For some species, body mass appeared to be influenced by the WNS invasion, but the response differed by species and reproductive state. Results suggest that continued long‐term monitoring studies, additional research into impacts of this disease on the fitness of WNS survivors, and a focus on providing optimal nonwintering habitat may be valuable strategies for assessing and promoting recovery of WNS‐affected bat populations., We used long‐term monitoring data to examine impacts from white‐nose syndrome on summer bat populations in West Virginia. The little brown bat, northern long‐eared bat, and tri‐colored bat all showed significant decreases in survey presence and relative abundance during and following the introduction of WNS, while the big brown bat and eastern red bat responded positively to the WNS invasion. We also investigate post‐WNS changes in adult female reproduction and body mass for those species in the study area.

Unmanned aerial vehicles (UAVs) are being explored by researchers to measure concentrations of gas emissions in situations where such measurements are otherwise extremely difficult to obtain, such as NO and NO2 (NOx) emissions from surface mine blasting. Recently, countries have imposed or are planning to impose surface blasting gas pollution regulations, which creates a need for an improved understanding of UAV-based gas measuring systems. The experiments detailed in this paper were performed to determine if airflow generated by the rotors, also known as downwash, unnaturally alters concentration measurements. Downwash turbulence could create locations of varying pressure, which could affect concentration. A UAV fitted with gas sensors was attached to a stand in a controlled environment containing a mixture of NOx. The gas sensor measuring points were placed at various distances on and from the UAV body to evaluate downwash effects on gas concentration. Results show that the presence of downwash turbulence causes no statistically significant changes to concentration measurements at any distance or direction from the UAV. Based on these results, it is possible to use a UAV-mounted gas monitor to measure concentrations without concern for downwash interference, provided the UAV and measuring point are entirely contained within the gas cloud.

InSight landed on Mars in November 20181 and carries the InSight FluxGate Magnetometer, IFG2 which has provided the first surface magnetic field measurements on Mars1,3. Previous magnetic field measurements taken at orbital altitudes have provided global coverage, with limited spatial resolution. Laboratory analyses of meteorites provide information on magnetic properties of martian rocks, but without detailed local context for their provenances4. Advances from the IFG are thus unique and complementary science, specifically characterizing the crustal ambient static and external time-varying fields at a single location on Mars. External fields provide information on the planet’s interaction with the interplanetary magnetic field and the ionosphere. Crustal magnetic fields carry information about the ancient dynamo and crustal conditions at the time at which magnetization was acquired, and on how the crust has been modified by subsequent exogenic and endogenic processes4. IFG data for sols 14-736 were collected almost continuously, with some data gaps from electronics anomalies. After sol 736, the magnetometer was operational for shorter periods due to power constraints (Fig. 1) 5. A range of studies have been enabled by IFG data, supported by results from other instruments such as the seismometer, and we summarize those.Strong crustal fields provide evidence for an ancient dynamo. The IFG measured a surface magnetic field strength of ~2000 nT, ~10x stronger than predicted from satellite data3,6 and consistent with an ancient Earth-like dynamo3. The strong surface field indicates that magnetization at wavelengths shorter than those resolvable from current satellite data (~150 km) contribute substantially to the overall magnetic field. Characterization of the crust through seismic measurements7 and geologic inferences3 of subsurface layering allow assessment of magnetization of the crust (Fig. 2). Depending on the depth at which the magnetization is carried, specifically whether it is in the seismically-determined deep layer of Noachian origin or also in the shallow Hesperian-aged crust, the minimum magnetization required to explain the surface field is ~2 A/m or ~0.4 A/m. Seismic characterization of crustal structure8 indicates a deep subsurface layer (> 20 km, Fig. 2) of no porosity, while the upper crust (8. Magnetization of these layers require an early active dynamo (>~4 Ga). Fractured, less porous material could have provided pathways for hydrothermal circulation and chemical remanent magnetization4,8,10. Magnetization of the most surficial layer of Hesperian age would be consistent with a long-lasting (up to ~3.7 Ga) dynamo9. IFG data also reveal time-varying fields at the planetary surface that include contributions with different periods and origins. External fields have been observed and characterized from orbit11–13. However, the degree to which external fields penetrate to and interact with the surface could not be studied prior to the InSight landing. Static and long-duration observations from a surface magnetometer are advantageous because, unlike satellite measurements, temporal variability in the field is not mixed with spatial variability. Here, we summarize different external magnetic field phenomena, transient and periodic that have been observed in IFG data (Fig. 3). Periodic variations include short period waves (100s-1000s3,14), diurnal variations15, the ~26 sol Carrington period associated with solar rotation16, and seasonal15,17 fluctuations. Transient events are observed in response to space weather18 and dust movement19,20.The inclusion of the magnetometer on InSight has provided unique and substantial scientific contributions to the overall mission results, as well as a starting point for future planetary surface magnetic field investigations. To overcome limitations of current data sets, we look forward to Mars sample return, as well as possible near-surface investigations. Including magnetometers on future missions at a variety of surface locations for long duration observations will be of great value in understanding a range of external field phenomena, including the influence of crustal magnetic fields on ionospheric currents and the effects of space weather during different phases of a solar cycle. We further advocate for regional investigations for example via a helicopter20 that can provide local magnetic field measurements at a spatial scale commensurate with detailed geological knowledge, to further constrain evolution of Mars’ ancient dynamo and explore the magnetic properties of the crust. Figure 1: a) Martian years 1 (blue) and 2 (red) of the magnetic field amplitude, B, versus solar longitude (ls). All data up to sol 1106 of InSight operations are included (PDS release 13). The blue vertical dashed line marks the beginning of the mission. (b) Corresponding sol numbers. Figure 2: The minimum magnetization required by B=2013 nT (within its 99% confidence intervals)21 for the crust below InSight8. Burial depth describes the depth extent of the unmagnetized layers above the top of the magnetized layer. A burial depth of 200 m (blue), corresponds to burial beneath the young (H: Hesperian, HNt: Hesperian-Noachian transition) near-surface lava flow3 and magnetizations are at least ~0.4 A/m if the entire underlying crust is magnetized. A burial depth of 10 km (blue) requires magnetizations >1 A/m, hosted by Noachian units. The velocity profiles show the seismically-determined interface depths7. Figure 3: A composite power spectral density (PSD) plot for the surface magnetic field strength at the InSight landing site. Estimates for longer periods are derived using a Lomb-Scargle algorithm (black), shorter periods (purple) show a Welch spectrum.[1] Banerdt, W. et al. Nat. Geosci. (2020).[2] Banfield, D. et al. SSR (2019). [3] Johnson, C. L. et al. Nat. Geosci.(2020). [4]Mitteholz, A. & Johnson, C. L. Frontiers (2022). [5] Joy, S. et. al. (2019). [6] Smrekar, S. et al. SSR (2018). [7] Knapmeyer-Endrun, B. et al. Science (2021). [8] Wieczorek, M. et al. JGR (2022). [9] Mittelholz, A. et al. Sci. Adv. (2020). [10] Gyalay, S. et al. GRL (2020). [11] Mittelholz, A. et al. JGR (2017). [12] Ramstad, R. et al. Nat. Astron. (2020). [13] Brain, D. et al. JGR (2003). [14] Chi, P. et al. LPSC (2019). [15] Mittelholz, A. et al. JGR (2020). [16] Luo, H. et al. JGR (2022). [17] Mittelholz, A. et al. LPSC (2021). [18] Mittelholz, A. et al. GRL (2021). [19] Thorne, S. et al. PSS (2022). [20] Bapst, J. et al. AAS (2021). [21] Parker, R. JGR (2003).

Well known as an expert on avian medicine, his patients benefited from his interest and ingenuity, supported by meticulous recording of what worked and what didn't.

EXECUTIVE SUMMARY Medical assistants-key professionals supporting physician practices-have not been studied with regard to burnout and professional fulfillment, which may affect other healthcare professionals. This study examined the factors associated with burnout among medical assistants in an academic healthcare organization while validating the use of a tool previously used to assess burnout in physicians. Using portions of the Professional Fulfillment Index (PFI) and questions designed for this mixed methods study, medical assistants employed across Stanford Health Care were surveyed. The authors assessed demographic characteristics and the impact of control, organizational culture, team knowledge, self-efficacy, and professional fulfillment/meaningfulness on burnout. Of the 505 eligible participants, 261 (52%) completed the survey; 76% were women. The study validated the PFI for use with this population and validated three additional scales. Burnout was found to be low among medical assistants (M = 2.32); professional fulfillment/meaningfulness of work was found to be high (M = 4.08). Organizational culture, professional fulfillment, and self-efficacy were found to be predictors of burnout (R2 = 0.438), with negative perceptions of organizational culture as the strongest predictor of burnout among medical assistants (β = -0.34). These results indicate that a survey tool is useful in understanding components of burnout and professional fulfillment in this population. Although limited to one site, this study could be replicated in other organizations.