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Sodium borate glasses doped with Nd3+ ions and having the molar formulations 75B 2 O 3 – 15Na 2 O – 9.5x – 0.5Nd 2 O 3 , where x = Bi 2 O 3 ; SrO and Li 2 O were prepared by employing the melt quenching technique. The glasses were coded as BiNd, SrNd, and LiNd for x = Bi 2 O 3 ; SrO and Li 2 O, respectively. The prepared glasses were characterized for their physical and optical attributes. The influence of the glass composition on the photoluminescence and fast neutron (FN) and charged radiation (CR) transmission efficiencies were also investigated. The density of BiNd, SrNd, and LiNd is 3.32, 2.43, and 3.32 g/cm3, respectively. Optical constants of the glasses showed variations with glass composition. The FTIR study of the glass also revealed the structure of the glasses. The BiNd glass has the most intense PL of all the samples, followed by SrNd glass, while LiNd had the weakest PL emission. The value of Σ R for BiNd, SiNd, and LiNd is 0.1029 cm−1, 0.1009 cm−1, and 0.0987 cm−1, respectively. The projected ranges of electrons, protons, helium ions, and carbon ions were generally lower for denser XNd glass. The XNd glasses are potentially useful of optical, shielding and dosimetry applications. [ABSTRACT FROM AUTHOR]

This article aims to use passive flow control to analyze the transportation of heat, mass, and charged particles toward a 3D plate. The current problem offers a novel exploration of the flexible domain of non-Newtonian materials, which are well known for their wide range of applications in the engineering and industrial domains. The current study explores the complex dynamics of heat and mass transfer in a fluid that flows over an elongating sheet. The motion of the nanofluid on the surface is caused by the stretching of the 3D plate. The suspension of mixtures of tetra-hybrid nanoparticles can enhance thermal performance and cooling mechanism. Moreover, the 3D model includes modeling of multiple important parameters, such as heat source, thermal radiation, and Hall and Ion slip effects, in Cartesian coordinates for a three-dimensional stretched plate. This comprehensive analysis of various effects offers a new perspective to the field. Partial differential equations represent the emergent phenomena in the problem formulation process. It was estimated that an enhancement of charged particles and motion regarding nanoparticles is enhanced versus an enhancement of charged particles. With the greater power law index, suction, and Weissenberg number, the acceleration of nanoparticles is enhanced.

In a recent study devoted to the influence of electromagnetic radiation reaction on the motion of radiating charged particles in magnetized black hole spacetimes the authors claim that the tail term cannot be neglected in the complete DeWitt–Brehme equation, putting into doubt the previous papers where such an approximation was used. Here, we demonstrate by using simple dimensional arguments that such a statement is misleading in many astrophysically relevant situations. In the case of relativistic electrons moving around a stellar-mass black hole, the tail term is ignorable if a magnetic field of at least a few Gauss is present.On the other hand, in different situations, the tail term can be relevant, as demonstrated in the case of orbital widening, where it can even amplify the effect. [ABSTRACT FROM AUTHOR]

Section of a NaCl-type lattice highlighting many-body interactions. [Display omitted] • Application of new theory to the treatment of many-body interactions between charged, dielectric particles. • Study of six particle lattice stoichiometries, AB, AB 2 , AB 3 , AB 4 , AB 5 and AB 6. • Calculations reveal the significance dielectric constant has for the stabilities of certain lattice types. • A new lattice isostructural with CFe 4 is found to be particularly stable due to many-body effects. Identifying the forces responsible for stabilising binary particle lattices is key to the controlled fabrication of many new materials. Experiments have shown that the presence of charge can be integral to the formation of ordered arrays; however, a complete analysis of the forces responsible has not included many of the significant lattice types that may form during fabrication. A theory of many-body electrostatic interactions has been applied to six lattice stoichiometries, AB, AB 2 , AB 3 , AB 4 , AB 5 and AB 6 , to show that induced multipole interactions can make a very significant (>80 %) contribution to the total lattice energy of arrays of charged particles. Particle radii ratios which favour global minima in electrostatic energy are found to be the same or a close match to those observed by experiment. Although certain lattice types exhibit local energy minima, the calculations show that many-body rather than two-body interactions are ultimately responsible for the structures observed by experiment. For a lattice isostructural with CFe 4 , a particle size ratio not previously observed is found to be particularly stable due to many-body effects. [ABSTRACT FROM AUTHOR]

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Hill fires, a sort of ultra-natural disaster that poses a severe threat to the safe and stable operation of transmission lines, have become more frequent in recent years. Currently, the modeling research on the transmission line gap electric field distortion under hill fire conditions does not consider the synergistic effect of charged particles and ash particles, which would lead to the imperfect gap electric field distortion mechanism. Herein, a coupled multi-physics field simulation model of electric, thermal, fluid, chemical field and particle motion was constructed to analyze the electric field distribution and particle motion. Compared to the related simulation models, this study improves the simulation accuracy by around 407% by optimizing the structure and parameters of the simulation model. The FEM software COMSOL Multiphysics simulation results show that the percentage of ash entering the examined region of the AC conductor was 34.1% higher, and the percentage of connected ash was 45% higher, increasing the likelihood of gap breakdown compared to the DC conductor; the charge of ash (10−14 to 10−11) is significantly less than the saturation charge of ash (⩾10−3). Therefore, the charged particles change the motion characteristics of the ash primarily through the electric field force and dielectrophoresis force, while the ash-induced distortion of the electric field affects the spatial distribution of the charged particles, eventually, the background electric field undergoes significant distortion by the synergistic effect of the two. The results examine the inherent mechanism of gap electric field distortion at the microscopic level, which can provide theoretical support for understanding the transition phase of transmission line gaps from insulation to break down under hill fire conditions. [ABSTRACT FROM AUTHOR]

Hybrid halide perovskites of the ABX3 composition are promising materials for use in optoelectronics and photovoltaics. To enhance the efficiency of structures based on perovskite, simulating the influence of the environment on the structures in laboratory conditions, irradiating them with various charged particles, has become a relevant task. This study explores possible irradiation methods for films with perovskite structures using various charged particles, such as alpha and gamma particles, protons, and electrons. Additionally, the impact of these processes on the properties and application domains of such structures is assessed. The research results showed that films based on perovskites (for example, CsPbBr3) have a very fast response (τ ∼5 ns) to irradiation with both alpha particles (with energy of ∼5 MeV) and protons. At the same time, they have the ability to fully restore to the initial conditions in a few hundred milliseconds after the cessation of irradiation. It has been shown that organic-inorganic hybrid perovskites are more sensitive to the action of an electron beam than inorganic onesAn increase in the dose of gamma irradiation leads to a decrease in the band gap (from 2,35 to 2,14 eV), a shift in the photoluminescence peak towards longer wavelengths and a decrease in the resistance of the grain boundaries. The effect of the gamma radiation dose on properties makes perovskite thin films very useful as sensor materials.

The detailed and comprehensive analysis of radiation processes in accretion disks consisting of electrically charged particles around black holes may provide powerful information about the spacetime geometry of the central black hole. We investigate the circular orbits of electrically charged particles around an electrically charged black-bounce Reissner–Nordström (RN) black hole, known as an RN Simpson–Visser (SV) black hole. We also study the profiles of the innermost stable circular orbits (ISCOs), energy, and angular momentum of the particles in their ISCOs, as well as the efficiency of energy release processes in the accretion disk in the Novikov–Thorne model. Finally, we calculate and study the effects of the black-bounce parameter as well as the black-hole charge on the intensity of the radiation of ultrarelativistic charged particles orbiting the charged RN SV black hole along circular orbits and falling into the black hole. It is observed that the black-bounce parameter essentially decreases the ISCO radius, and consequently the energy extraction and intensity of electromagnetic radiation. [ABSTRACT FROM AUTHOR]

Computer simulations of the DNA damage are widely used due to their large application area. The computational methods to predict DNA breaks are based on molecular concepts about the formation of breaks, the geometric structure of DNA, and information about the distribution of absorbed energy in a DNA molecule. Intercomparison of the accuracy of calculations performed by different schemes is commonly difficult, since the calculations employ different prerequisites, postulates, and algorithms. The same applies to determination of the parameters of the DNA lesion models due to scatter of experimental data. A comparative analysis of predictions is performed based on two basic models of the DNA structure, that is, the molecular and volume, which use different assumptions with respect to the formation mechanism of single- and double-strand DNA breaks, in the case of irradiation of DNA molecules with protons and α-particles. Calculations of the efficiency of radiation-induced DNA damage, considering contribution of the direct effect, molecular structure of DNA, and stochastic structure of charged tracks show the dependence of the frequency of occurrence of DNA damage on the model parameters. The parameter domains were found, within which predictions generated by the models are either in agreement or differ from one another. [ABSTRACT FROM AUTHOR]

We show that relativistic rotation transformations represent transfer maps between the laboratory system and a local observer on an observer manifold, rather than an event manifold, in the spirit of C-equivalence. Rotation is, therefore, not a parameterised motion on a background space or spacetime, but is determined by a particular sequence of tetrads related by specific special Lorentz transformations or boosts. Because such Lorentz boosts do not form a group, these tetrads represent distinct observers that cannot put together their local descriptions into a manifold in the usual sense. The choice of observer manifold depends on the dynamical situation under consideration, and is not solely determined by the kinematics. Three examples are given: Franklin's rotation transformation for uniform plane rotation, the Thomas precession of a vector attached to an electron, and the motion of a charged particle in an electromagnetic field. In each case, at each point of its trajectory, there is a distinguished tetrad and a special Lorentz transformation that maps Minkowski space to the spacetime of the local observer on the curve. [ABSTRACT FROM AUTHOR]

Triboplasma should be one of the main causes of the tribochemical reactions. In this report the distributions and intensities of the neutral and charged radicals produced in the triboplasma generated in the rear gap of the sliding contact has been analyzed using the PIC/MCC simulation method for the tribosystem of a diamond pin with a tip radius of 300 μm sliding on a sapphire disk in ambient air. Side distribution images of three kinds of neutral radicals of N, O and O1D and an anion radical O− were analyzed. They coincided well the experimentally observed side image of the triboplasma. Further, the maximum densities and the total numbers of the intermediate particles were calculated for the neutral radicals of N, O and O1D and the charged particles of e−, O−, N2+ and O2+. They showed that both the maximum densities and the total numbers of the neutral particles of N, O and O1D are much higher than those of the charged particles of e−, N2+, O2+ and O−. The latter intensities of the charged particles were even negligibly small compared to those of neutral particles. This means that most of the particles exist in the triboplasma are neutral radicals such as N, O and O1D. This concludes that the tribochemical reactions due to triboplasma are caused mainly through the active intermediates of the neutral radicals. [ABSTRACT FROM AUTHOR]

The results of separation of a polydisperse mixture of charged dielectric microparticles using a linear electrodynamic quadrupole trap in air at atmospheric pressure are presented. It has been experimentally shown that the sizes of the microparticles held by the trap strongly depend on the voltage at the linear electrodes. [ABSTRACT FROM AUTHOR]

The proposed deep space exploration to the moon and later to Mars will result in astronauts receiving significant chronic exposures to space radiation (SR). SR exposure results in multiple neurocognitive impairments. Recently, our cross-species (mouse/rat) studies reported impaired associative memory formation in both species following a chronic 6-month low dose exposure to a mixed field of neutrons (1 mGy/day for a total dose pf 18 cGy). In the present study, we report neutron exposure induced synaptic plasticity in the medial prefrontal cortex, accompanied by microglial activation and significant synaptic loss in the hippocampus. In a parallel study, neutron exposure was also found to alter fluorescence assisted single synaptosome LTP (FASS-LTP) in the hippocampus of rats, that may be related to a reduced ability to insert AMPAR into the post-synaptic membrane, which may arise from increased phosphorylation of the serine 845 residue of the GluA1 subunit. Thus, we demonstrate for the first time, that low dose chronic neutron irradiation impacts homeostatic synaptic plasticity in the hippocampal-cortical circuit in two rodent species, and that the ability to successfully encode associative recognition memory is a dynamic, multicircuit process, possibly involving compensatory changes in AMPAR density on the synaptic surface.

In a recent study devoted to the influence of electromagnetic radiation reaction on the motion of radiating charged particles in magnetized black hole spacetimes the authors claim that the tail term cannot be neglected in the complete DeWitt–Brehme equation, putting into doubt the previous papers where such an approximation was used. Here, we demonstrate by using simple dimensional arguments that such a statement is misleading in many astrophysically relevant situations. In the case of relativistic electrons moving around a stellar-mass black hole, the tail term is ignorable if a magnetic field of at least a few Gauss is present.On the other hand, in different situations, the tail term can be relevant, as demonstrated in the case of orbital widening, where it can even amplify the effect.

Nanoparticles are used in many industrial processes due to their wider applications. The current inspection deals the utilization of nanoparticles to boost thermal efficiency. This research reports the inclusion of nanoparticles and dust particles for the flow of tri-hybridized nanofluid with thermal transport in a stretchable porous sheet with Hall and Ion slip contribution. The mechanism of thermal transport is carried out by engaging the radiation and Joule heating effects and the flow-presenting equations are derived from the principle of boundary layer theory in Cartesian coordinates. The principle of boundary layer theory was engaged to derive momentum transport for tri-hybridized nanoparticles, dust particles and thermal transport in the presence of Joule heating and external heat sources. The derived equations are in the form of coupled PDEs (partial differential equations) for three-dimensional model which are converted into coupled ODEs (ordinary differential equations) and the simplified expressions are handled numerically via finite element procedure. The results are prepared for the solution in the form of tables and graphs against different involved parameters. The results reveal that thermal enhancement and motion of the particles for the case of the fluid phase are higher than the thermal enhancement and motion for the case of the dusty phase and additionally, thermal performance for the case of tri-hybrid nano-structures (SiO2-TiO2-Al2O3/engine oil) is higher than thermal performance for the cases of hybrid nano-fluid.

In this work, we consider the dynamics of ion fluxes and magnetic field changes in turbulent regions of magnetotail dipolarizations. The data from the Cluster-II mission (magnetic field measurements from fluxgate magnetometers and energetic charged particle observations from RAPID spectrometers) were used for the analysis. We study individual events and investigate statistically the changes of charged particle fluxes during magnetic field dipolarizations observed during 2001–2015. Received changes in the spectral index indicate that CNO+ ions undergo stronger acceleration during dipolarization than protons and helium ions. Before dipolarization front monotonic growth the ions flux is observed (the maximum of flux is observed at 1–1,5 min after the start of dipolarization) in the range of ∼ 92–374 keV for proton; in the energy range ∼ 138–235 keV for He+ and in the energy range of 414–638 keV for CNO+ ions. Flux increase before arriving dipolarization front may result from the reflection of plasma sheet ions at the dipolarization front and the result of the resonant interactions of ions with low-frequency electromagnetic waves.

Radiological properties of some chemotherapy drugs such as Doxorubicin, Vincristine, Teniposide, Azathioprine, Etoposide, Cyclophosphamide, Vinblastine and Bleomycin were investigated according to total electron interaction and some heavy charged particle interactions on behalf of effective atomic numbers (Zeff) and electron densities (Neff) for the first time. Calculations were performed for total electron, proton and C ion interactions, commonly used in therapy, in the energy region 10 keV-400 MeV. Variation of Zeffs and Neffs of given drugs was studied according to the energy of electron or heavy charged particles and significant variations were observed for all types of interaction in the given energy region. The highest values of Zeff were found in the different regions of energy for different particle interactions remarkably and variation in Neff seems approximately to be same with alteration in Zeff for the investigated drugs. Also, Zeff values of all drugs were plotted together and compared with each other for electron, proton and C ion interactions in the continuous energy region. Maximum and minimum values of Zeff were observed in Azathioprine (6.14) and Vinblastine (2.25) for electron interaction and proton interaction in the continuous energy region, respectively. The obtained results were compared with the Phy-X/ZeXTRa program between 10 keV-15 MeV energy region. [ABSTRACT FROM AUTHOR]

Experiments on the synthesis of superheavy elements (SHE) performed at the Flerov Nuclear Reactions Laboratory (FLNR) have shown that the probability of a single SHE event occurrence range from one event per month to one event per week. Currently, the heaviest element synthesized in reactions with Ca is an element with (Oganesson). To synthesize new SHEs, it is necessary to use heavier bombarding particles such as Ti, Cr, Fe, etc. In experiments with heavier particles, the cross-section for SHE isotope production is expected to be lower than that in the case of using Ca. This implies that an increase in the intensity of the bombarding ion beams is necessary to collect experimental statistics within a reasonable time frame. Thus, for the synthesis of superheavy elements at the FLNR of the Joint Institute for Nuclear Research (JINR), the Superheavy Element Factory was created. The basic setup of the Factory is the cyclotron complex DC-280, which allows for the production of high-intensity beams of accelerated ions. As the beam intensity increases, the energy spread also increases. To minimize this process, the DC-280 cyclotron is equipped with an additional flat-top accelerating system. [ABSTRACT FROM AUTHOR]

We study the dynamics and oscillations of electrically charged particles along stable circular orbits around a nonrotating electrically charged spacetime. In this work, we consider a regularized Reissner–Nordström (RN) spacetime under the transformation r 2 → r 2 + l 2 , known as the black-bounce-RN (or Simpson–Visser RN) spacetime, which can represent both a black hole and a wormhole depending on the values of l , in the presence of braneworld effects. In our analyses, we introduce a new parameter that shows a similar gravitational effect, which includes electric (Q) and tidal charges (B) of the spacetime as b = Q 2 + B. We investigate the horizon properties of the spacetime and estimate the parametric distributions that describe a black hole and a wormhole. Furthermore, we analyze the effective potential of the particles and the critical angular momentum for the cases dominated by the tidal charge b < 0 and the electric charge b > 0 , respectively. Moreover, we apply the epicyclic frequencies in the relativistic precession model to fit twin high-frequency (HF) quasiperiodic oscillations (QPOs) observed in microquasars and active galactic nuclei. Finally, we apply a Monte Carlo Markov Chain (MCMC) simulation to constrain the multidimensional parameter space for the microquasars GRO J1655-40 & GRS 1915-105 and the galactic center, for being a black hole and wormhole candidate using observational data from QPOs. Our findings suggest that the central object of the Milky Way and the microquasars GRS 1915-105 may be a black hole and a wormhole with certain parameters. However, there are no constraints for the microquasar GRO J1655-40 obtained regarding the wormhole case. It implies that the central object fails to be a candidate for being a wormhole in the black-bounce charged spacetimes in the braneworlds model. [ABSTRACT FROM AUTHOR]

The detailed and comprehensive analysis of radiation processes in accretion disks consisting of electrically charged particles around black holes may provide powerful information about the spacetime geometry of the central black hole. We investigate the circular orbits of electrically charged particles around an electrically charged black-bounce Reissner–Nordström (RN) black hole, known as an RN Simpson–Visser (SV) black hole. We also study the profiles of the innermost stable circular orbits (ISCOs), energy, and angular momentum of the particles in their ISCOs, as well as the efficiency of energy release processes in the accretion disk in the Novikov–Thorne model. Finally, we calculate and study the effects of the black-bounce parameter as well as the black-hole charge on the intensity of the radiation of ultrarelativistic charged particles orbiting the charged RN SV black hole along circular orbits and falling into the black hole. It is observed that the black-bounce parameter essentially decreases the ISCO radius, and consequently the energy extraction and intensity of electromagnetic radiation.

High-energy charged particles are considered particularly hazardous components of the space radiation environment. Such particles include fully ionized energetic nuclei of helium, silicon, and oxygen, among others. Exposure to charged particles causes reactive oxygen species production, which has been shown to result in neuronal dysfunction and myelin degeneration. Here we demonstrate that mice exposed to high-energy charged particles exhibited alterations in dendritic spine density in the hippocampus, with a significant decrease of thin spines in mice exposed to helium, oxygen, and silicon, compared to sham-irradiated controls. Electron microscopy confirmed these findings and revealed a significant decrease in overall synapse density and in nonperforated synapse density, with helium and silicon exhibiting more detrimental effects than oxygen. Degeneration of myelin was also evident in exposed mice with significant changes in the percentage of myelinated axons and g-ratios. Our data demonstrate that exposure to all types of high-energy charged particles have a detrimental effect, with helium and silicon having more synaptotoxic effects than oxygen. These results have important implications for the integrity of the central nervous system and the cognitive health of astronauts after prolonged periods of space exploration.

The paper presents the study of the spectral densities of random processes in a underdamped system of particles in a trap with effective violation of the symmetry of the interparticle interaction. Such stationary systems can be realized, e.g., for dust microparticles in gas discharges. Analytical relations are proposed for the spectral density of oscillations of both identical and different-sort particles in such systems. The relations obtained are verified by numerical simulation of particle dynamics. [ABSTRACT FROM AUTHOR]

A detector of the proton telescope type utilized at the RFNC-VNIIEF for detection of DT neutrons and the principle of its operation are described. The main goal of the study was to simulate the spectra of recoil protons in the detector, which includes taking into account the kinematics of elastic H(n, n) scattering, proton energy losses in hydrogen-containing radiator and scintillator, and nonlinearity of the light yield of inorganic scintillators. The spectra of recoil protons for several neutron energies have been simulated and compared with data of experiments on DT neutrons. [ABSTRACT FROM AUTHOR]

The oxidation of carbon monoxide on the surface of the Au/Al2O3/Mo(110) structure was studied using modern methods of surface diagnostics. It is shown that at a high degree of identity of the structural, electronic, and adsorption properties of the Au/Al2O3/Mo(110) system with various aluminum oxide film thicknesses (2, 4, 6, and 8 monolayers), the oxidation efficiency of CO molecules desorbed into the gas phase decreases exponentially with increasing oxide film thickness. Taking into account the well-known fact that the efficiency of CO oxidation depends on the amount of the excess charge acquired by the gold nanoparticle, it is concluded that charge tunneling through the oxide layer increases the efficiency of the reaction on the surface of the studied metal oxide system. [ABSTRACT FROM AUTHOR]

The increased demand for ionizing radiation in various fields led to the search for new shielding substances. In this study, five samples of perovskite oxides (BaTiO 3 , SrTiO 3 , BaTiO 3 –SrTiO 3 , and PbZr 0.2 Ti 0.8 O 3) doped YBa 2 Cu 3 O y ceramics were prepared to explore their structure and ability for exploitation in the radiation shielding field. The structural properties were explored by using the XRD technique. The XRD results showed an orthorhombic structure for all prepared ceramics. The crystallite size reduces gradually from 96.19 to 66.63 nm with adding different perovskite oxides into the composites. The density shows a variation from about 5.89 to 6.23 g/cm3. The mass attenuation coefficient (MAC) was defined experimentally (MAC) exp and theoretically (MAC) the to check its validity. The maximum relative difference between (MAC) exp and (MAC) the is 7.83%. YBa 2 Cu 3 O 7 /(PbZr 0.2 Ti 0.8 O 3) 2% and YBa 2 Cu 3 O 7 /(BaTiO 3 –SrTiO 3) 2% samples showed superior gamma shielding properties and mass stopping power (MSP) for charged particles, respectively, while the pristine YBa 2 Cu 3 O 7 sample has a better fast neutron removal cross-section (Σ R). From the obtained results, it can be seen a slight variation in shielding properties, indicating the ability to use the different ceramic samples as radiation shielding materials. [ABSTRACT FROM AUTHOR]

The experimental studies results of Coulomb structures in a vertically oriented linear electrodynamic Paul trap at atmospheric air pressure are presented. Stable cone-shaped Coulomb structures are obtained. It is found that the particles in such structures move along closed trajectories with small amplitudes with the frequency of the alternating field of the trap. [ABSTRACT FROM AUTHOR]

Study questionDo charged iron particles, components of space radiation, cause premature ovarian failure?Summary answerExposure to charged iron particles causes ovarian DNA damage, oxidative damage and apoptosis, resulting in premature ovarian failure.What is known alreadyThe ovary is very sensitive to follicle destruction by low linear energy transfer (LET) radiation, such as X-rays and γ-rays. However, it is completely unknown whether high-LET radiation, such as charged iron particles, also destroys ovarian follicles.Study design, size, durationTwelve week old C57BL/6J female mice were exposed to single doses of 0, 5, 30 or 50 cGy (n = 8/group) charged iron particles (LET = 179 keV/µm) at energy of 600 MeV/u. Two groups were irradiated at the highest dose, one fed AIN-93M chow and the other fed AIN-93M chow supplemented with 150 mg/kg diet alpha lipoic acid (ALA).Participants/materials, setting, methodsWe quantified the numbers of ovarian follicles, measured serum follicle stimulating hormone (FSH) and luteinizing hormone (LH) concentrations, and analyzed histone H2AX phosphorylation, oxidative damage and apoptosis markers in the ovarian follicles.Main results and the role of chanceH2AX phosphorylation, lipid peroxidation, protein nitration and apoptosis were highly induced in ovarian follicles at 6 h and remained increased 1 week after irradiation. As a result, numbers of healthy ovarian follicles were significantly and dose-dependently depleted at 1 and 8 weeks post-irradiation, with 57, 84 and 99% decreases in primordial follicles at 8 weeks at the 5, 30 and 50 cGy doses, respectively (P < 0.05 versus 0 cGy). Consistent with near-total depletion of ovarian follicles in the 50 cGy group, serum concentrations of FSH and LH were significantly elevated at 8 weeks. Dietary supplementation with ALA partially prevented the adverse ovarian effects of 50 cGy iron particles.Limitations, reasons for cautionAbout 21% of the estimated radiation dose from exposure to galactic cosmic rays during a multi-year Mars mission will be due to high-LET particles, of which iron is only one. The effects of galactic cosmic rays, which contain a mixture of multiple charged particles, as well as protons, neutrons, and helium ions, may differ from the effects of iron alone.Wider implications of the findingsWe show for the first time that charged high-LET ions are highly damaging to the ovary even at low doses, causing premature ovarian failure. In addition to raising concerns for female astronauts, these findings raise concerns for ovarian damage due to clinical uses of high-LET particles for cancer treatment. In addition to causing infertility, premature ovarian failure has adverse implications for the functions of heart, brain, bone and muscle later in life.Study funding/competing interestsThis work was supported by a National Aeronautics and Space Administration grant NNX14AC50G to U.L. B.M. was partially supported by a National Space Biomedical Research Institute First Award, PF04302. Additional support was received from the University of California Irvine Center for Occupational and Environmental Health. The authors have no conflicts of interests.

Electromagnetic response of clustered charged particles is the foundation of electromagnetic wave interaction with various natural phenomena, such as sandstorm, cloud, and volcano eruption. Previous studies usually employed assumption of independent charged particles, without considering the coupling between them. Here, we build up a general numerical model considering the multiple scattering effect, and test it with a charged two- and four-particle system. The numerical results show that independence assumption fails, while the number density of clustered charged particles is getting larger. This work may pave the way for deeper understanding on the electromagnetic interaction of clustered charged particles.