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Accelerator-based ion-beam irradiation has been widely used to mimic the effects of neutron radiation damage in nuclear reactors. However, ion radiation is most often monodisperse in the incoming ions’ momentum direction, leading to excessive polarization in defect distribution, while the scattering under neutron irradiation is often more isotropic and has less radiation-induced polarization. Mitigation of the excess-polarization as well as the damage non-uniformity artifact might be crucial for making the simulation of neutron radiation by ion-beam radiation more realistic. In this work, a general radiation polarization theory in treating radiation as external polar stimuli is established to understand the natural material responses in different contexts, and the possibility to correct the defect polarization artifact in ion-beam irradiation. Inspired by Magic Angle Spinning in Nuclear Magnetic Resonance, we present a precise sample spinning strategy to reduce the point-defect imbalance effect in ion-beam irradiation. It can be seen that with optimized surface inclination angle and the axis of sample rotation, the vacancy-interstitial population imbalance, as well as the damage profile non-uniformity in a designated region in the target are both reduced. It is estimated that sample spinning frequency on the order of kHz should be sufficient to scramble the ion momentum monodispersity for commonly taken ion fluxes and dose rates, which is experimentally feasible.

Biological soil crusts (biocrusts) are crucial elements of desert ecosystems, exhibiting patchy distribution patterns across the soil surface and significantly impacting surface soil nutrient dynamics. However, the influence of biocrust patch units, serving as fundamental functional entities, on microbial nutrient restriction remains underexplored. This study conducted measurements on moss crust patches of varying sizes and subcrust soils. Stoichiometric analysis of extracellular enzyme activities (EEAs) related to carbon, nitrogen, and phosphorus was performed, along with vector and redundancy analyses to evaluate microbial nutrient limitation and key influencing factors. The findings reveal that both patch size and soil layer of biocrusts collectively influence soil nutrients and enzyme dynamics, with heightened enzyme activity observed in the crust layer. Vector analysis based on EEA stoichiometry indicates that moss crust patch size insignificantly impacts microbial nutrient restriction within the crust layer. However, microbial nitrogen restriction in the subcrust layer demonstrates a “single-peak” trend, initially increasing before gradually declining. This suggests that microorganisms in medium-sized crust patches exhibit peak activity, intensifying nutrient competition. This research underscores the pivotal role of biocrust patch units as fundamental functional entities, offering comprehensive insights into microbial metabolic constraints under crust cover. The findings underscore the significant implications of enzyme stoichiometric characteristics for desert land management and conservation. [ABSTRACT FROM AUTHOR]

SRIM-like codes have limitations in describing general 3D geometries, for modeling radiation displacements and damage in nanostructured materials. A universal, computationally efficient and massively parallel 3D Monte Carlo code, IM3D, has been developed with excellent parallel scaling performance. IM3D is based on fast indexing of scattering integrals and the SRIM stopping power database, and allows the user a choice of Constructive Solid Geometry (CSG) or Finite Element Triangle Mesh (FETM) method for constructing 3D shapes and microstructures. For 2D films and multilayers, IM3D perfectly reproduces SRIM results, and can be ∼10(2) times faster in serial execution and > 10(4) times faster using parallel computation. For 3D problems, it provides a fast approach for analyzing the spatial distributions of primary displacements and defect generation under ion irradiation. Herein we also provide a detailed discussion of our open-source collision cascade physics engine, revealing the true meaning and limitations of the "Quick Kinchin-Pease" and "Full Cascades" options. The issues of femtosecond to picosecond timescales in defining displacement versus damage, the limitation of the displacements per atom (DPA) unit in quantifying radiation damage (such as inadequacy in quantifying degree of chemical mixing), are discussed.

The shrub and patch size of moss crusts can significantly affect plant and soil nutrients. The effects and relationships of shrubs and moss crusts on soil multifunctionality are unclear. This study aimed to understand the spatial heterogeneity of soil multifunctionality in moss crust patches and shrubs. Soil organic carbon, nutrient, and enzyme activities under moss crust patches were measured. Interestingly, the soil polyphenol oxidase (PPO) and peroxidase (POD) activities, carbon‐related soil multifunctionality index (C‐SMF), nitrogen‐related soil multifunctionality index (N‐SMF), phosphorus‐related soil multifunctionality index (P‐SMF), and soil multifunctionality index (SMF) increased with increasing patch size in moss crusts. The patch size of moss crusts had no significant effect on the C‐SMF, N‐SMF, P‐SMF, and SMF under the shrub. The soil C‐SMF, N‐SMF, P‐SMF, and SMF under shrubs were significantly higher than that in exposed areas (EAs). The soil PPO, POD, N‐SMF, P‐SMF, and SMF under dead shrubs were significantly higher than those under living shrubs and in EAs. Evaluation and composition analysis of C‐SMF, N‐SMF, and P‐SMF indicated that moss crust promotes the increase of P‐SMF, and that shrub promotes the increase of C‐SMF and N‐SMF. Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling. Shrub promotes soil carbon and nitrogen functionality. This study elucidates the effect of moss crust patch size on soil multifunctionality influenced by shrub growth in desert ecosystems and provides further new insights into the soil processes and functions. Results are beneficial for the comprehensive utilization of fertile islands and its enhancement of beneficial ecological functions, such as maintaining soil nutrition, quality, health, and vegetation restoration, and lay a foundation for future research on nutrient absorption and utilization between mosses and shrubs. Core Ideas: The patch size effect of moss crusts is a positive in soil multifunctionality and is influenced by microhabitats.Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling.Shrub patches mainly affected soil carbon and nitrogen functionality. [ABSTRACT FROM AUTHOR]

OBJECTIVES The Haller index (HI) is widely utilized as a quantitative indicator to assess the extent of the pectus excavatum (PE) deformity, which is the most common chest wall abnormality in children. Both preoperative correction planning and postoperative follow-up need to be based on the standard of normal thoracic growth and development. However, there is currently no established reference range for the HI in children. Consequently, the goal of this study was to conduct a preliminary investigation of normal HI values among children to understand thoracic developmental characteristics. METHODS Chest computed tomography images obtained from January 2012 to March 2022 were randomly selected from the imaging system of the Children's Hospital of Chongqing Medical University. We divided the images of children into a total of 19 groups: aged 0–3 months (1 group), 4–12 months (1 group) and 1 year to 17 years (17 groups), with 50 males and 50 females, totaling 100 children in each group. HI was measured in the plane where the lowest point of the anterior thoracic wall was located and statistically analysed using SPSS 26.0 software. RESULTS A total of 1900 patients were included in the study. Our results showed that HI, transverse diameter and anterior-posterior diameter were positively correlated with age (P  <   0.05). Using age as the independent variable and HI as the dependent variable, the best-fit regression equations were HI-male = 2.047 * Age0.054(R2 = 0.276, P<0.0001) and HI-female = 2.045 * Age0.067(R2 = 0.398, P<0.0001). Males had significantly larger thoracic diameters than females, and there was little difference in the HI between the 2 sexes. CONCLUSIONS The HI rapidly increases during the neonatal period, slowly increases during infancy and stops increasing during puberty, with no significant differences between the sexes. [ABSTRACT FROM AUTHOR]

Aim: To explore the effects of HSP90 on rotavirus (RV) replication. Materials & methods: The interaction between NSP2 and HSP90 was analyzed by immunoprecipitation assay, and co-localization confirmed by an immunofluorescence assay. The viral titer was measured by immunofluorescence assay and viral protein expression investigated by western blotting. Results: The interaction between NSP2 and HSP90 was confirmed. Knockdown of HSP90 using siRNA resulted in a decrease in NSP2 expression and virus titer. HSP90 inhibitor 17-AAG significantly decreased NSP2 and NSP5 expression, as well as the virus titer, while proteasome inhibitor MG132 restored the protein amount and the viral titer. Conclusion: HSP90 is involved in rotavirus replication, and inhibition of HSP90 promotes the degradation of NSP2 through the proteasome pathway. Rotavirus is a type of virus that causes severe diarrhea, especially in children. The virus infects the cell in our bodies. These cells have proteins which carry out important functions and can help the growth of the virus. One of these proteins, called HSP90, interacts with a protein of the virus, called NSP2. After infection, these proteins move to the same place within the cell. Decreasing the level of HSP90 also decreases the level of NSP2, slowing the growth of the virus. Understanding how HSP90 and NSP2 work will help to develop new drugs to treat rotavirus infection. Article highlights Background Heat shock protein 90 (HSP90) appears to play an essential role in viral replication, but little is known regarding the role of HSP90 in rotavirus (RV) infection. Methods RV laboratory strain SA11 was used in this study. Virus titers were measured by Fluorescent formation units assay and viral protein expression checked by WB. The interaction of HSP90 and NSP2 was confirmed by immunoprecipitation (IP) and confocal laser microscope. siRNA used to knockdown the expression of HSP90 and HSP90 activity was inhibited. Results The HSP90 inhibition resulted in decreased RV replication. Knockdown of HSP90 by siRNA decreased RV protein levels and virus replication. HSP90 interacted with virus protein NSP2. Inhibition of the proteasome pathway decreased viral protein degradation. Conclusion HSP90 was used by RV to facilitate virus replication by chaperoning viral proteins and preventing their degradation via the proteasome. [ABSTRACT FROM AUTHOR]