Life Sciences in Space Research最新文献

{"title":"Charge-weighted quality factors based on LET for practical dose assessment of space radiation","authors":"Masayuki Naito,&nbsp;Satoshi Kodaira","doi":"10.1016/j.lssr.2025.10.002","DOIUrl":"10.1016/j.lssr.2025.10.002","url":null,"abstract":"<div><div>We demonstrate a new charge weighted quality factor, noted Q*, based on the practical application of particle linear energy transfer (LET) and charge (Z)-dependent quality factors for LET-based radiation dosimetry in space. Z contribution factors are defined according to the energy spectra of galactic cosmic rays (GCRs). The Z-weighted quality factor depending solely on the LET (Q*) under solar minimum conditions in free space differs by only a few percent from values obtained with spacecraft shielding or during the solar maximum spectrum. Q* values based on various biological endpoints exhibit peaks at higher LETs than those defined in ICRP-60. The reduced contribution of GCR heavy components under Q*, compared to Q_ICRP of ICRP-60, suggests that current dose assessments may be overestimated. The proposed Q* approach is applicable to different LET- and Z-dependent quality factors, and provides practical dose evaluation using LET measurements.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"51 ","pages":"Pages 25-32"},"PeriodicalIF":3.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148302407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DNA decompaction enhances the formation of radiation-induced DNA double strand breaks and chromosome aberrations","authors":"Floriane Poignant,&nbsp;Victor Levrague,&nbsp;Mathieu Roccia,&nbsp;Ngoc Hoang Tran,&nbsp;Sebastien Incerti,&nbsp;Michael Beuve,&nbsp;Etienne Testa,&nbsp;Ianik Plante,&nbsp;Shirin Rahmanian,&nbsp;Rachel Delorme","doi":"10.1016/j.lssr.2025.10.006","DOIUrl":"10.1016/j.lssr.2025.10.006","url":null,"abstract":"<div><div>Chromosome aberrations, a biomarker of space radiation-induced carcinogenesis, are a direct consequence of DNA double-strand break (DSB) misrepair and play an important role in the fate of irradiated cells. Their formation is a function of different physical and biological factors including the 3D DNA architecture. At the nanometric scale, the DNA is wrapped around histone proteins to form nucleosomes, which fold together to form the chromatin fiber. Different levels of DNA density exist, namely the less compact euchromatin (EC) and the denser heterochromatin (HC). Recent studies showed that EC is more prone to DNA damage than HC at the same dose, suggesting that DNA compaction might influence chromosome aberration formation.</div><div>In this work, we investigated how DNA compaction at the nucleosome level influences the formation of DSBs and total exchanges for exposure to high charge and energy ions (HZE) with linear energy transfer (LET) in the range 0.4 - 235 keV/μm. The radiation transport tool RITRACKS and DNA damage and chromosome aberration model RITCARD allow the transport of HZE ions in cell nuclei and evaluate the yield of DNA damage and chromosome aberrations but does not provide detailed geometries of the DNA with different compaction levels. In contrast, Geant4-DNA provide atomic scale models of HC or EC DNA and can be used to evaluate DNA damage. We combined Geant4-DNA and RITCARD to model radiation transport, DNA damage and DNA repair in fibroblast cell nuclei filled with EC or HC and compared the results to those obtained by RITRACKS/RITCARD. For all cell nuclei, the 3D distribution of the DNA was obtained with the tool G-NOME using experimental chromosome conformation capture (Hi-C) data.</div><div>Large differences were obtained for the yield of DSB between RITRACKS/RITCARD and Geant4 DNA (-25% - 125% for HC nuclei), reflecting major differences in how the two models score DNA damage, which were responsible for large differences (-50% - 150% for HC nuclei) in the yield of total exchanges. For Geant4-DNA, we found that DNA decompaction increased the yield of DNA DSB by 4–8%, depending on the ion LET. The effect was more pronounced for total exchanges, with an increased yield of 50–75% for EC nuclei compared to HC nuclei. This larger total exchange yield was attributed mainly to differences in DNA distribution across the cell nucleus and, to a lesser extent, the increased DSB yield. Euchromatin nuclei presented chromosome domains that were more spread out, likely favoring inter-chromosomal proximity at the periphery of chromosome territories and, therefore, chromosome rearrangements. These findings provide further evidence that DNA compaction could be a factor of cell radiosensitivity.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"51 ","pages":"Pages 45-55"},"PeriodicalIF":3.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148302371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing space radiation risk assessment for deep space missions","authors":"Satoshi Kodaira,&nbsp;Teruaki Konishi,&nbsp;Floriane Poignant","doi":"10.1016/j.lssr.2026.06.002","DOIUrl":"10.1016/j.lssr.2026.06.002","url":null,"abstract":"<div><div>To assess the risks posed by space radiation, the dose equivalent, defined as the integral of the measured absorbed dose and the radiation quality factor (Q), is currently employed. The Q is closely related to cancer risk estimation, as it reflects the relative biological effectiveness of radiation. These relationships have been investigated using several biological endpoints in anticipation of future space missions. The International Commission on Radiological Protection (ICRP) addressed radiation exposure in space using Q, as detailed in ICRP Publication 123. Currently, the Q–LET relationship established in ICRP Publication 60 for general dose assessment on the ground is applied in space dosimetry. However, a Q value that takes track structure into account has been developed to evaluate radiation risks associated with specific biological effects. For future deep space missions, a more practical Q value specifically adapted to the characteristics of space radiation may be required for accurate dose assessment. This special issue explores new frontiers in space radiation risk assessment by integrating recent advances in physical and biological research, including microdosimetry and studies of inter- and intra-cellular responses.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"51 ","pages":"Pages 1-2"},"PeriodicalIF":3.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148302350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Irradiation of condensed CO reveals a new pathway for the formation of aromatic molecules in astrochemical ices","authors":"Wafikul Khan ,&nbsp;R Ramachandran ,&nbsp;S Gupta ,&nbsp;J K Meka ,&nbsp;V Venkataraman ,&nbsp;B N Rajasekhar ,&nbsp;P Janardhan ,&nbsp;Anil Bhardwaj ,&nbsp;N J Mason ,&nbsp;B Sivaraman","doi":"10.1016/j.lssr.2025.09.007","DOIUrl":"10.1016/j.lssr.2025.09.007","url":null,"abstract":"<div><div>Given the importance of carbon monoxide in the interstellar medium (ISM) both in the gas and ice phase, the condensed phase CO has been studied by the irradiation of energetic particles, UV irradiation and the products formed from CO dissociation have been investigated for nearly four decades. However, our understanding on the physical nature of the residue made from CO ice irradiation is limited to-date. Hence we irradiated CO ice with 2 keV electrons and probed the ice using vacuum ultraviolet / ultraviolet (VUV/UV) spectroscopy techniques. The <em>in-situ</em> VUV/UV spectral analysis of irradiated product provided compelling evidence (peak at ∼ 240 nm) for the presence of a refractory residue made of carbon atoms. The ex-situ analysis carried out using high resolution transmission electron microscopy (HR-TEM) revealed the presence of ordered carbon atoms viz-a-viz graphene, graphitic carbon and graphitic quantum dots. The direct ring closure from carbon atoms released from CO reveal a new pathway to be considered in the bottom-up formation of polycyclic aromatic hydrocarbon (PAH) molecules, on cold dust in the ISM, via the hydrogenation of graphene / graphitic carbon.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 94-100"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deciphering chemical heritage: Isotopic study of methanol and other complex organic molecules in a solar-type protostar NGC 1333 IRAS 4A2","authors":"Dipen Sahu","doi":"10.1016/j.lssr.2025.11.003","DOIUrl":"10.1016/j.lssr.2025.11.003","url":null,"abstract":"<div><div>Hot corinos are early-stage low-mass protostars where many complex organic molecules (COMs) are detected. Understanding these organics is important to reveal their heritage in later evolutionary stages. Isotopic studies are an effective way to uncover the chemical heritage and gain insights into the astrophysical processes involved. In this study, we present a comprehensive analysis of COMs and their isotopologues in the NGC 1333 IRAS 4A2 hot corino, focusing on their excitation temperatures, column densities, and formation pathways. Using high-resolution ALMA observations and LTE spectral modeling, we identified deuterated isotopologues of several COMs, and for methanol and some other species we also detected ¹³C- and ¹⁸O-substituted forms. The derived excitation temperatures (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mtext>ex</mtext></mrow></msub></math></span>) range from 80 to 200 K, indicating diverse thermal conditions within the hot corino. Although the limited spatial resolution and spectral width prevented resolving individual emission regions, our findings suggest a chemical stratification consistent with steep temperature gradients observed in similar environments. Our analysis reveals that molecular binding energies of the species are primarily responsible for this chemical stratification and align well with the temperature gradient observed in similar regions. Additionally, the isotopic and deuterium fractionation observed in IRAS 4A2 is lower than that reported for IRAS 16293-2422B, possibly reflecting hotter inner regions or faster formation timescales. These results provide new insights into the physical and chemical processes governing hot corinos during star formation.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 35-47"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Astrochemistry: The building blocks of life in the universe","authors":"Ankan Das ,&nbsp;Robin T. Garrod","doi":"10.1016/j.lssr.2026.01.007","DOIUrl":"10.1016/j.lssr.2026.01.007","url":null,"abstract":"<div><div>This Special Issue brings together eleven articles that collectively advance our understanding of molecular formation, transformation, and survival across a broad range of astrophysical environments. The contributions investigate radiation-driven chemistry, ice-mediated processes, the evolution of complex organic molecules, and the coupled physical–chemical structure of protostellar and hot-core regions through a combination of laboratory experiments, theoretical modeling, and astronomical observations. Together, the studies demonstrate how key factors-including irradiation, temperature, elemental abundance ratios, ice composition, and dynamical structure—govern the chemistry of both simple and complex species. As a whole, this collection provides an integrated perspective on the processes that build, preserve, and observationally reveal molecular complexity throughout the interstellar medium.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 1-3"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cosmic fertilization? Implantation of astrobiologically relevant cosmic rays in molecular clouds","authors":"Sergio Pilling ,&nbsp;Maurício T. Pazianotto","doi":"10.1016/j.lssr.2025.06.003","DOIUrl":"10.1016/j.lssr.2025.06.003","url":null,"abstract":"<div><div><span>This study investigates the implantation of astrobiologically relevant elements (e.g., carbon (C), oxygen (O), nitrogen (N), sulfur (S) and phosphorus (P)) into molecular clouds<span> induced by cosmic rays. Using the Monte Carlo toolkit Geant4, we simulated the interaction of incoming high-energy protons and alpha particles with a molecular clump characterized by a centrally concentrated density profile and a mass of approximately 30 M</span></span>_⊙<span>. The results reveal a spatial gradient in implantation rates, with the highest rates occurring in the central regions due to increased target densities and reduced projectile energy. Protons (p) dominate the implantation process across all regions, followed by O, C, N, S, and P, with element-specific implantation efficiencies varying with distance from the clump center. This research identified regions inside the molecular cloud with distinct domains of atomic implantation enrichment with implications for astrobiology. The region at </span><span><math><mo>∼</mo></math></span><span>1 AU exhibits the interesting atom implantation enrichment of the studied atoms, making it particularly significant for the formation of complex organic molecules. The findings highlight the importance of cosmic ray interactions in selectively enriching specific regions of molecular clouds with astrobiologically essential elements.</span></div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 61-70"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiative transfer modeling of the low-mass proto-binary system, IRAS 4A1 and 4A2","authors":"Bratati Bhat ,&nbsp;Ankan Das ,&nbsp;Prasanta Gorai ,&nbsp;Dipen Sahu","doi":"10.1016/j.lssr.2025.11.002","DOIUrl":"10.1016/j.lssr.2025.11.002","url":null,"abstract":"<div><div>NGC 1333 IRAS4A is a well-studied low-mass sun-like proto-binary system. It has two components, A1 and A2, which are diverse according to their physical and chemical properties. We modeled this hot corino using the RATRAN radiative transfer code and explained different spectral signatures observed towards A1 and A2, specifically for CH<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>OH and H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>CO. Our main goal is to understand the kinematical and chemical differences between A1 and A2 and to classify their dust emission and absorption properties. We considered a simple 1D spherical infalling envelope consisting of collimated outflow in the source. Recent high-resolution interferometric observations of ALMA shed new light on why the same molecular transitions towards A1 and A2 show different spectral profiles. The significant difference between spectral profiles observed towards A1 and A2 is mainly due to the dust opacity effect. Dust continuum emission towards A1 is optically thick, causing the transitions observed in absorption. Meanwhile, A2 is optically thin, leading to the observed emission profiles, and an inverse P-Cygni profile suggests the presence of an infalling envelope. Using high-resolution observations from ALMA and VLA, we expanded our model from the millimeter wavelength range to the centimeter wavelength range. This expansion demonstrates the opacity effect, which is reduced in the centimeter wavelength range, causing us to observe the lines in emission. Using our model, we reproduced the population inversion causing maser emission of methanol 44 GHz and 95 GHz transitions.</div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 48-60"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent observational studies on carbon-chain species with current facilities and future prospects with ALMA & JWST","authors":"Kotomi Taniguchi ,&nbsp;Ryan M. Lau ,&nbsp;Masao Saito","doi":"10.1016/j.lssr.2025.05.002","DOIUrl":"10.1016/j.lssr.2025.05.002","url":null,"abstract":"<div><div>Carbon-chain species have been widely found in star-forming regions and are considered to form via a bottom-up mechanism in which ionic and atomic carbon (C<span><math><msup><mrow></mrow><mrow><mo>+</mo></mrow></msup></math></span> and C) play essential roles. Recent deep line survey observations toward the Cyanpolyyne Peak in Taurus Molecular Cloud-1 (hereafter TMC-1 CP) have achieved the discovery of new carbon-bearing species; <span><math><mrow><mi>e</mi><mo>.</mo><mi>g</mi><mo>.</mo><mo>,</mo></mrow></math></span><span> large hydrocarbon rings and species including benzene rings such as cyanobenzene, cyanonaphthalene, and cyanopyrene. The bottom-up mechanism cannot explain their presence and now we need to revisit the carbon chemistry in the interstellar medium<span> (ISM). One possible approach is to explore the carbon chemistry from evolved stars<span> where carbon is ejected into the ISM through the diffuse ISM to the next-generation star-forming regions, or molecular clouds. Combining ALMA and JWST, we will be able to explore carbon chemistry including top-down mechanisms.</span></span></span></div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 29-34"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability of ice-embedded glycine under space ionizing radiations: a RT-TD-DFT and DFT study","authors":"Dahbia Talbi ,&nbsp;Stella Christodoulou ,&nbsp;Maysa Yusef Buey ,&nbsp;Mathias Rapacioli ,&nbsp;Tzonka Mineva","doi":"10.1016/j.lssr.2025.06.009","DOIUrl":"10.1016/j.lssr.2025.06.009","url":null,"abstract":"<div><div><span>The energy depositions and charge variations induced by the collision of a glycine molecule embedded in an amorphous ice with a 46 MeV Ni¹¹</span>⁺<span> ionizing radiation were investigated using RT-TD-DFT theory. The resulting fragmentation from this interaction was analyzed using DFT theory. Our study shows that the impact of the projectile on the surrounding water-ice molecules has a negligible effect on the charge exchange between the glycine and water subsystems while a direct collision of the projectile with the glycine molecule results in its significant ionization despite the water environment.</span></div></div>","PeriodicalId":18029,"journal":{"name":"Life Sciences in Space Research","volume":"49 ","pages":"Pages 88-93"},"PeriodicalIF":2.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147307353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}