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Our understanding of the ion-sputtering contribution to the formation of exospheres on airless bodies has been hindered by the lack of accurate surface binding energies (SBEs) of the elements in the various mineral and amorphous compounds expected to be on the surfaces of these bodies. The SBE for a given element controls the predicted sputtering yield and energy distribution of the ejecta. Here, we use molecular dynamics computations to provide SBE data for the range of elements sputtered from plagioclase feldspar crystalline end members, albite and anorthite, which are expected to be important mineral components on the surfaces of the Moon and Mercury. Results show that the SBE is dependent on the crystal orientation and the element’s coordination, meaning multiple SBEs are possible for a given element. Variation in the SBEs among the different surface positions has a significant effect on the predicted yield and energy distribution of the ejecta. We then consider sputtering by H, He, and a solar wind mixture of 96% H and 4% He. For each of these cases, we derive best-fit elemental SBE values to predict the ejecta energy distribution from each of the (001), (010), and (011) cleavage planes. We demonstrate that the He contribution to the sputtering yield cannot be accounted for by multiplying the 100% H results by some factor. Lastly, we average our results over all three possible lattice orientations and provide best-fit elemental SBE values that can be easily incorporated into sputtering yield models.

We have measured the absolute doubly differential angular sputtering yield for 20 keV Kr+ impacting a polycrystalline Cu slab at an incidence angle of θi = 45° relative to the surface normal. Sputtered Cu atoms were captured using collectors mounted on a half dome above the sample, and the sputtering distribution was measured as a function of the sputtering polar, θs, and azimuthal, ϕs, angles. Absolute results of the sputtering yield were determined from the mass gain of each collector, the ion dose, and the solid angle subtended, after irradiation to a total fluence of ∼1 × 1018 ions/cm2. Our approach overcomes shortcomings of commonly used methods that only provide relative yields as a function of θs in the incidence plane (defined by the ion velocity and the surface normal). Our experimental results display an azimuthal variation that increases with increasing θs and is clearly discrepant with simulations using binary collision theory. We attribute the observed azimuthal anisotropy to ion-induced formation of micro- and nano-scale surface features that suppress the sputtering yield through shadowing and redeposition effects, neither of which are accounted for in the simulations. Our experimental results demonstrate the importance of doubly differential angular sputtering studies to probe ion sputtering processes at a fundamental level and to explore the effect of ion-beam-generated surface roughness. [ABSTRACT FROM AUTHOR]

The 2021 Leonard Medal was awarded to Dr. Katharina Lodders, in person, at the 2021 Annual Meeting of the Meteoritical Society in Chicago, IL, USA. This is the citation presented for Dr. Lodders. [ABSTRACT FROM AUTHOR]

Within this work, we present the first true three‐dimensional (3D) analysis of chondrule size. Knowledge about the physical properties of chondrules is important for validating astrophysical theories concerning chondrule formation and their aggregation into the chondritic meteorites (known as chondrites) that contain them. The classification of chondrites into chemical groups also relies on chondrule properties, including their dimensions. Within this work, we quantify the diameters of chondrules in five ordinary chondrites (OCs; comprised of the H, L, and LL chondrites) and one low‐iron enstatite (EL) chondrite. To extract the chondrule size data, we use x‐ray computed microtomography to image small (~1–2 cm3) chondrite samples followed by manual digital segmentation to isolate chondrules within the volumes or subvolumes. Our data yield true 3D results without stereographic corrections necessary for two‐dimensional (2D) or petrographic thin section‐based determinations of chondrule sizes. Our results are completely novel, but are consistent with previous surface analysis (2D) data for OCs. Within our OC chondrule diameter data, we find the trend of mean chondrule diameters increasing in the order H < L < LL. We also present the first detailed EL chondrite chondrule size‐frequency distribution. Finally, we examine the shapes and collective orientations of the chondrules within the chondrites and show that chondrite petrofabrics can be explored with our methodology. Chondrule shape‐preferred orientations are identical to the orientations of the metal and sulfide grains in the chondrites and this is likely due to impact‐related compaction. Highlights: We present a first true three‐dimensional analysis of chondrule size.Our ordinary chondrite chondrule diameter data demonstrate the trend of mean chondrule diameters increasing in the order H chondrites < L chondrites < LL chondrites.We also present the first detailed low‐iron enstatite chondrite chondrule size‐frequency distribution.We examine the shapes and collective orientations of the chondrules and show that chondrite petrofabrics can be explored with our methodology. [ABSTRACT FROM AUTHOR]

Background: The standard of care in tobacco treatment is to continue individuals who smoke on the same cessation medication, even when they do not stop smoking. An alternative strategy is to adapt pharmacotherapy based on non-response. A handful of studies have examined this approach, but they have adapted pharmacotherapy only once and/or focused on adaptation distal rather than proximal to a failed quit attempt. Few studies have included racial/ethnic minorities who have less success in quitting and bear a disproportionate share of tobacco-related morbidity and mortality. Methods: The current study is comparing the efficacy of optimized (OPT) versus enhanced usual care (UC) for smoking cessation in African Americans (AA) who smoke cigarettes. AAs who smoke (n = 392) are randomized 1:1 to OPT or UC. Participants in both groups receive 7 sessions of smoking cessation counseling and18-weeks of pharmacotherapy with long-term follow-up through Week 26. OPT participants receive nicotine patch and up to two pharmacotherapy adaptations to varenicline and bupropion plus patch based on carbon monoxide verified smoking status (≥6 ppm) at Weeks 2 and 6. UC participants receive patch throughout the duration of treatment. We hypothesize that OPT will be more effective than UC on the primary outcome of biochemically verified abstinence at Week 12. Discussion: If effective, findings could broaden the scope of tobacco dependence treatment and move the field toward optimization strategies that impro ve abstinence for AA who smoke. Trial registration: NCT03897439.

The enstatite chondrite class is known to have complex thermal histories, often interpreted to include impact melting and shock metamorphism. Highly equilibrated (type 6) EH group enstatite chondrites are rare and thought to have formed through collisional heating. We studied two EH6 chondrites, NWA 7976 and NWA 12945, for their textural, chemical, and mineralogical characteristics. The samples we studied contain subhedral to anhedral grains of enstatite and plagioclase, suggesting solid‐state recrystallization. They show low degrees of shock and no evidence of shock melting. Additionally, the ubiquitous occurrence of daubréelite exsolution lamellae in troilite and the Ni content of schreibersite suggest slow cooling at greater burial depths in the parent body, rather than rapid cooling as a result of an impact event. Based on the characteristics and scarcity of type 6 EH chondrites, and the ubiquitous shock effects and melt rocks in the enstatite chondrite class, we conclude that the unshocked NWA 7976 and NWA 12945 were formed by heat derived from impact melt sheets, analogous to contact metamorphism. [ABSTRACT FROM AUTHOR]

The geology of New York City (USA) consists primarily of metasedimentary rocks that were deformed during the series of orogenies between ca. 470 Ma and ca. 300 Ma that culminated in the amalgamation of Pangea. The rocks in New York City play a key role in understanding the tectonic history of these orogenies because they lie at a critical location at the boundary between the Northern and Southern Appalachian Mountains. The primary question addressed here is where these metasedimentary rocks originated prior to the assembly of Pangea. Through detrital zircon and whole-rock Nd isotope analyses, we show that all the metasedimentary rocks of New York City, mapped as the Manhattan Schist and the Hartland Group, are primarily derived from Laurentia as indicated by detrital zircon populations dominated by 1200-900 Ma grains and εNd values between -7 and -13. The results presented here do not necessitate an exclusively Laurentian source for the detrital material found in New York City, but the data strongly suggests protoliths represent sedimentary units that are primarily derived from the Laurentian margin. Another important result from this study is the limited contributions from any rift volcanics and/or Gondwanan material(s). There is some subtle variability across our zircon sample suite, but there is no convincing evidence for major changes in bulk provenance signal that would be consistent with derivation from vastly different continental sources for these rocks. The shared provenance signal observed here is counter to the previous suggestions that a major terrane boundary, often called Cameron's Line, exists in New York City, separating Laurentian rocks from those of a Gondwanan affinity. [ABSTRACT FROM AUTHOR]

Ehrlichia chaffeensis is an obligatory intracellular bacterium that infects monocytes and macrophages and causes human monocytic ehrlichiosis. Ehrlichia translocated factor-3 (Etf-3) is a type IV secretion system effector that binds host-cell ferritin light chain and induces ferritinophagy, thus increasing cellular labile iron pool for Ehrlichia proliferation. To further characterize roles of Etf-3 in Ehrlichia infection, we produced immune libraries of Etf-3-specific nanobodies (Nbs). Based on distinct complementarity-determining region 3 sequences, we identified 16 and 15 families of anti-Etf-3 Nbs that could specifically bind the N- and C-terminal halves of Etf-3, respectively. Transfection with plasmids encoding the anti-Etf-3 Nbs N48 and N51, but not N59, significantly inhibited E. chaffeensis infection in HEK293 cells. All three Nbs colocalized with Etf-3-GFP in co-transfected RF/6A cells, but N48 and N51 had significantly higher binding affinities for recombinant Etf-3. Etf-3-GFP transfection-induced ferritinophagy and endogenous ferritin degradation was abrogated in HEK293 cells co-transfected with N48 or N51, but not with N59. To efficiently express Nbs in the infected host-cell cytoplasm, lipid nanoparticles-encapsulated mRNAs (LNP-mRNAs) encoding N48, N51, or N59 were created for delivery into cells or mice. Incubation of HEK293 cells or inoculation of mice with LNP-mRNA-N48 or LNP-mRNA-N51 significantly inhibited E. chaffeensis infection compared to those with LNP-mRNA-N59 or without LNP-mRNA. Our results demonstrate that Etf-3-specific Nbs delivered via LNP-mRNAs can inhibit Etf-3 functions and Ehrlichia infection., (Copyright © 2024. Published by Elsevier GmbH.)

Ehrlichiosis is a potentially life-threatening disease caused by infection with the obligatory intracellular bacteria Ehrlichia species. Ehrlichia japonica infection of mice provides an animal model of ehrlichiosis as it recapitulates full-spectrum and lethal ehrlichiosis in humans. The E. japonica transposon mutant of EHF0962 , which encodes a previously uncharacterized hypothetical protein, is attenuated in both infection and virulence in mice. EHF0962 was hence named here as resistance-inducing protein of Ehrlichia (RipE). Using this Δ ripE mutant, we studied how RipE protein contributes to Ehrlichia pathogenesis. Ehrlichia species have an intracellular developmental cycle and a brief extracellular stage to initiate a new cycle of infection. Majority of RipE proteins were expressed on the surface of the smaller infectious dense-core stage of bacteria. Extracellular Δ ripE E. japonica contained significantly less adenosine triphosphate (ATP) and lost infectivity more rapidly in culture compared with wild-type (WT) E. japonica . Genetic complementation in the Δ ripE mutant or overexpression of ripE in WT E. japonica significantly increased bacterial ATP levels, and RipE-overexpressing E. japonica was more virulent in mice than WT E. japonica . RipE is conserved among Ehrlichia species. Immunization of mice with recombinant RipE induced an in vitro infection-neutralizing antibody, significantly prolonged survival time after a lethal dose of E. japonica challenge, and cross-protected mice from infection by Ehrlichia chaffeensis , the agent of human monocytic ehrlichiosis. Our findings shed light on the extracellular stage of Ehrlichia , highlighting the importance of RipE and ATP levels in Ehrlichia for extracellular resistance and the next cycle of infection. Thus, RipE is a critical Ehrlichia protein for infection as such can be a potential vaccine target for ehrlichiosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Chien, Lin, Duan, Denton, Kawahara and Rikihisa.)

Objective. Making up one of the largest shares of diagnosed cancers worldwide, skin cancer is also one of the most treatable. However, this is contingent upon early diagnosis and correct skin cancer-type differentiation. Currently, methods for early detection that are accurate, rapid, and non-invasive are limited. However, literature demonstrating the impedance differences between benign and malignant skin cancers, as well as between different types of skin cancer, show that methods based on impedance differentiation may be promising. Approach. In this work, we propose a novel approach to rapid and non-invasive skin cancer diagnosis that leverages the technologies of difference-based electrical impedance tomography (EIT) and graphene electronic tattoos (GETs). Main results. We demonstrate the feasibility of this first-of-its-kind system using both computational numerical and experimental skin phantom models. We considered variations in skin cancer lesion impedance, size, shape, and position relative to the electrodes and evaluated the impact of using individual and multi-electrode GET (mGET) arrays. The results demonstrate that this approach has the potential to differentiate based on lesion impedance, size, and position, but additional techniques are needed to determine shape. Significance. In this way, the system proposed in this work, which combines both EIT and GET technology, exhibits potential as an entirely non-invasive and rapid approach to skin cancer diagnosis., (© 2024 Institute of Physics and Engineering in Medicine.)

Background & Aims: The Remote Malnutrition Application (R-MAPP) was developed during the COVID-19 pandemic to provide support for health care professionals (HCPs) working in the community to complete remote nutritional assessments and provide practical guidance for nutritional care. R-MAPP was adapted into Pediatric Remote Malnutrition Application (Pedi-R-MAPP) using a modified Delphi consensus, with the goal of providing a structured approach to completing a nutrition focused assessment as part of a technology enabled care service (TECS) consultation. The aim of this study was to develop and validate a digital version of Pedi-R-MAPP using the IDEAS framework (Integrate, Design, Assess and Share)., Methods: A ten-step process was completed using the IDEAS framework. This involved the four concept processes; Stage-1, Integrate (Step 1-3) identify the problem, specify the goal, and use an evidence-based approach. Stage-2, (Step 4-7) design iteratively and rapidly with user feedback. Stage 3, (Step 8-9) Assess rigorously, and Stage 4 (Step 9-10) publish and launch of the tool., Results: Stage 1:Evidence-based development, Pedi-R-MAPP was developed using Delphi consensus methodology. Stage 2:Iteration & design, HCPs (n = 22) from UK, Europe, South Africa, and North America were involved four workshops to further develop a paper prototype of the tool and complete small-scale testing of a beta version of the tool which resulted in eight iterations. Stage 3:Assess rigorously, Small scale retrospective testing of the tool on children with congenital heart disease (n = 80) was completed by a single researcher, with iterative changes made to improve agreement with summary advice. Large scale testing amongst (n = 745) children in different settings was completed by specialist paediatric dietitians (n = 15) advice who recorded agreement with the summary advice compared with their own clinical assessment. Paediatric dietitians were in overall agreement with the summary advice in the tool 86% (n = 640), compared to their own clinical practice. The main reasons for disagreement were i) frequency of planned review 57.1% (n = 60/105), ii) need for ongoing dietetic review due to chronic condition 20.0% (n = 21/105), iii) disagreement with recommendation for discharge 16.2% (n = 17/105) and iv) concerns with faltering growth and/or need for condition specific growth charts 6.7% (7/105). Iterative changes were made to the algorithm, leading to an improvement in agreement of the summary advice on re-evaluation to 98% (p=<0.0001)., Conclusion: A digital version of the Pedi-R-MAPP nutrition awareness tool was developed using the IDEAS framework. The summary advice provided by the tool achieved a high level of agreement when compared to paediatric dietetic assessment, by providing a structured approach to completing a remote nutrition focused assessment, along with identifying the frequency of follow-up or an in-person assessment., Competing Interests: Conflict of interest Dr Marino reports an unrestricted grant from Abbott Laboratories, during the conduct of the study. Dr Marino reports honoraria from ABBOTT Laboratories and Danone-Nutricia outside the submitted work. No other conflicts of interest from other authors in relation to this study were reported., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Hallucinations can occur in single or multiple sensory modalities. Greater attention has been paid to single sensory experiences with a comparative neglect of hallucinations that occur across two or more sensory modalities (multisensory hallucinations). This study explored how common these experiences were in people at risk of transition to psychosis (n=105) and considered whether a greater number of hallucinatory experiences increased delusional ideation and reduced functioning, both of which are associated with a greater risk of transition to psychosis. Participants reported a range of unusual sensory experiences, with two or three being common. However, when a strict definition of hallucinations was applied, in which the experience has the quality of a real perception and in which the person believes them to be real experiences, then multisensory experiences were rare and when reported, single sensory hallucinations in the auditory domain were most common. The number of unusual sensory experiences or hallucinations was not significantly associated with greater delusional ideation or poorer functioning. Theoretical and clinical implications are discussed., Competing Interests: Declaration of Competing Interest RD receives payment for workshops in treating hallucinations and GD, CA and RD declare they are involved in running treatment studies investigating psychological therapies for psychosis. All other authors declare no competing interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Fall risk assessment is a complex phenomenon involving several risk factors, including an individual's balance and mobility status, chronic health conditions, visual impairment, hearing deficits, environmental hazards (e.g., loose rugs, clutter), and being homebound or semi-homebound. Comprehensive fall risk assessment is the cornerstone of fall prevention in older adults throughout the community. The current study was based on secondary data and sought to examine variables associated with death due to accidental fall in a rural, midwestern county in Illinois, and to heighten awareness for consistent screening and risk assessment in older adults residing in the community. Results illustrated that among community-dwelling older adults with accidental falls, blunt injury or subdural hematoma had significantly fewer days until death than a fracture. [ Journal of Gerontological Nursing, 48 (6), 26-32.].

Auditory verbal hallucinations (AVHs)-or hearing voices-occur in clinical and non-clinical populations, but their mechanisms remain unclear. Predictive processing models of psychosis have proposed that hallucinations arise from an over-weighting of prior expectations in perception. It is unknown, however, whether this reflects (i) a sensitivity to explicit modulation of prior knowledge or (ii) a pre-existing tendency to spontaneously use such knowledge in ambiguous contexts. Four experiments were conducted to examine this question in healthy participants listening to ambiguous speech stimuli. In experiments 1a ( n  = 60) and 1b ( n  = 60), participants discriminated intelligible and unintelligible sine-wave speech before and after exposure to the original language templates (i.e. a modulation of expectation). No relationship was observed between top-down modulation and two common measures of hallucination-proneness. Experiment 2 ( n  = 99) confirmed this pattern with a different stimulus-sine-vocoded speech (SVS)-that was designed to minimize ceiling effects in discrimination and more closely model previous top-down effects reported in psychosis. In Experiment 3 ( n  = 134), participants were exposed to SVS without prior knowledge that it contained speech (i.e. naïve listening). AVH-proneness significantly predicted both pre-exposure identification of speech and successful recall for words hidden in SVS, indicating that participants could actually decode the hidden signal spontaneously. Altogether, these findings support a pre-existing tendency to spontaneously draw upon prior knowledge in healthy people prone to AVH, rather than a sensitivity to temporary modulations of expectation. We propose a model of clinical and non-clinical hallucinations, across auditory and visual modalities, with testable predictions for future research., (© The Author(s) 2022. Published by Oxford University Press.)