Proton Ion Research Articles

Simulated galactic cosmic ray exposure activates dose-dependent DNA repair response and down regulates glucosinolate pathways in arabidopsis seedlings.

Outside the protection of Earth's magnetic field, organisms are constantly exposed to space radiation consisting of energetic protons and other heavier charged particles. With the goal of crewed Mars exploration, the production of fresh food during long duration space missions is critical for meeting astronauts' nutritional and psychological needs. However, the biological effects of space radiation on plants have not been sufficiently investigated and characterized. To that end, 10-day-old Arabidopsis seedlings were exposed to simulated Galactic Cosmic Rays (GCR) and assessed for transcriptomic changes. The simulated GCR irradiation was carried out in the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Lab (BNL). The exposures were conducted acutely for two dose points at 40 cGy or 80 cGy, with sequential delivery of proton, helium, oxygen, silicon, and iron ions. Control and irradiated seedlings were then harvested and preserved in RNAlater at 3 hrs post irradiation. Total RNA was isolated for transcriptomic analyses using RNAseq. The data revealed that the transcriptomic responses were dose-dependent, with significant upregulation of DNA repair pathways and downregulation of glucosinolate biosynthetic pathways. Glucosinolates are important for plant pathogen defense and for the taste of a plant, which are both relevant to growing plants for spaceflight. These findings fill in knowledge gaps of how plants respond to radiation in beyond-Earth environments.

Structural and electrical study of novel Ba3SrNb2O9 triple perovskite based solid electrolyte for LT-SOFCs

Solid Electrolytes (SOE) with high ionic conductivity highly desirable in order to improve the efficiency of SOFCs at lower functioning temperature range) (350–500 °C). Triple perovskite Ba3SrNb2O9 based proton ion conductor have up-and-coming to enhance ionic conductivity at Low temperature range (LT) (350–500 °C). With this motivation we have successfully synthesized Ba3SrNb2O9 (BSNO) by solgel combustion method. Powder X-ray diffraction (XRD) confirms the formation of Triclinic crystal structure having space group P1, having lattice dimensions (a = 5.89340 Å, b = 5.88760 Å, c = 7.27360 Å). Rietveld Refinement of XRD data was carried out to get detail structural information by Full-Prof suite software. Electrical performance of the BSNO system were systematically studied by Electrochemical Impedance spectroscopy at functioning temperature 350–500 °C with interval of 50 °C. BSNO system exhibit conductivity of the order of 5.8 × 10−3 Scm−1 at 500 °C with the activation energy of the range of 0.48 eV. Charge Relaxations phenomenon very systematically explored by impedance loss spectra and it is very correlate with Modulus (M’’) as a function of frequency at several temperatures which used to clarify the charge relaxation dynamics in proton ion conducting BSNO material.

Development of PVA-ABO3 organic-inorganic nanocomposite proton exchange membrane for HT-PEMFCs

In this study for the first time, poly(vinyl alcohol) (PVA)-ABO3 (BaCeO3/SrCeO3/SrZrO3) nanocomposite membranes were prepared as proton exchange membrane for high-temperature proton exchange membranes fuel cell (HT-PEMFC). Proton ion-conducting material based on perovskite ceramic ABO3 were prepared by sol-gel combustion method. PVA-ceramic nanocomposite membrane containing BaCeO3, SrCeO3, SrZrO3, nanoparticles in various compositions were developed by solutions casting method. Structural features are confirmed by X-ray diffraction (XRD) and FTIR. Uniform dispersion of ceramic particles in polymer membrane is confirmed by scanning electron microscopy. Proton-conducting ability of the composite membranes was revealed by impedance spectroscopy. The ion-conducting ability of the membrane was studied under three conditions (1) by hydrating the membrane, (2) by phosphoric acid doping, and (3) by sulphuric acid doping. Proton conductivity of phosphoric acid doped nanocomposite membrane is found to be highest amongst the others. The dynamics of proton ion conduction were revealed by electric modulus spectrum. The composite membrane exhibited good mechanical strength and thermal stability up to 120 °C. The PVA-BaCeO3 (PVA-BCO) composite membrane demonstrates maximum proton ion conductivity 2.84 × 10−3 S/cm as compared to PVA and other PVA-based composites at 120 °C using phosphoric acid doping. For PEMFC applications, phosphoric acid-doped composite membranes made of PVA and barium cerate (BaCeO3) have a high potential of effectiveness.

Computational approaches in the estimation of radiobiological damage for human-malignant cells irradiated with clinical proton and carbon beams

Purpose:The use of Monte Carlo (MC) simulations capable of reproducing radiobiological effects of ionising radiation on human cell lines is of great importance, especially for cases involving protons and heavier ion beams. In the latter, huge uncertainties can arise mainly related to the effects of the secondary particles produced in the beam-tissue interaction. This paper reports on a detailed MC study performed using Geant4-based approach on three cancer cell lines, the HTB-177, CRL-5876 and MCF-7, that were previously irradiated with therapeutic proton and carbon ion beams. Methods:A Geant4-based approach used jointly with analytical calculations has been developed to provide a more realistic estimation of the radiobiological damage produced by proton and carbon beams in tissues, reproducing available data obtained from in vitro cell irradiations. The MC “Hadrontherapy” Geant4 application and the Local Effect Model: LEM I, LEM II and LEM III coupled with the different numerical approaches: RapidRusso (RR) and RapidScholz (RS) were used in the study. Results:Experimental survival curves are compared with those evaluated using the highlighted Geant4 MC-based approach via chi-square statistical analysis, for the combinations of radiobiological models and numerical approaches, as outlined above. Conclusion:This study has presented a comparison of the survival data from MC simulations to experimental survival data for three cancer cell lines. An overall best level of agreement was obtained for the HTB-177 cells.

Visualizing the Promoting Role of Interfacial Water in the Deprotonation of Formic Acid on Cu(111).

Water plays a crucial role in various heterogeneous catalytic reactions, but the atomic-scale characterization of how water participates in these chemical processes remains a significant challenge. Here we directly visualize the promoting role of interfacial water in the deprotonation of formic acid (FA) on a metal surface, using combined scanning tunneling microscopy and qPlus-based noncontact atomic force microscopy. We find the dissociation of FA when coadsorbed with water on the Cu(111) surface, resulting in the formation of hydronium and formate ions. Interestingly, most of the hydrated proton and formate ions exhibit a phase-separated behavior on Cu(111), in which Eigen and Zundel cations assemble into a monolayer hexagonal hydrogen-bonding (H-bonding) network, and bidentate formate ions are solvated with water and aggregate into one-dimensional chains or two-dimensional H-bonding networks. This phase-separated behavior is essential for preventing the proton transfer back from hydronium to formate and the reformation of FA. Density functional theory calculations reveal that the participation of water significantly reduces the deprotonation barrier of FA on Cu(111), in which water catalyzes the decomposition of FA through the Grotthuss proton transfer mechanism. In addition, the separate solvation of hydronium and bidentate formate ions is energetically preferred due to the enhanced interaction with the copper substrate. The promoting role of water in the deprotonation of FA is further confirmed by the temperature-programmed desorption experiment, which shows that the intensity of the H2 desorption peak significantly increases and the desorption of FA declines when water and FA coadsorbed on the Cu(111) surface.

Proton and helium ions acceleration in near-critical density gas targets by short-pulse Ti:Sa PW-class laser

The ability to quickly refresh gas-jet targets without cycling the vacuum chamber makes them a promising candidate for laser-accelerated ion experiments at high repetition rate. Here we present results from the first high repetition rate ion acceleration experiment on the VEGA-3 PW-class laser at CLPU. A near-critical density gas-jet target was produced by forcing a 1000 bar H $_2$ and He gas mix through bespoke supersonic shock nozzles. Proton energies up to 2 MeV were measured in the laser forward direction and 2.2 MeV transversally. He $^{2+}$ ions up to 5.8 MeV were also measured in the transverse direction. To help maintain a consistent gas density profile over many shots, nozzles were designed to produce a high-density shock at distances larger than 1 mm from the nozzle exit. We outline a procedure for optimizing the laser–gas interaction by translating the nozzle along the laser axis and using different nozzle materials. Several tens of laser interactions were performed with the same nozzle which demonstrates the potential usefulness of gas-jet targets as high repetition rate particle source.

Characterization of Secondary Neutron Spectra from Therapeutic Proton and Carbon Ion Beams Using PHITS Simulation

Characterization of Secondary Neutron Spectra from Therapeutic Proton and Carbon Ion Beams Using PHITS Simulation

Design study of a novel geometrical arrangement for an in-beam small animal positron emission tomography scanner

Objective. We designed a geometrical solution for a small animal in-beam positron emission tomography (PET) scanner to be used in the project SIRMIO (Small animal proton irradiator for research in molecular image-guided radiation-oncology). The system is based on 56 scintillator blocks of pixelated LYSO crystals. The crystals are arranged providing a pyramidal-step shape to optimize the geometrical coverage in a spherical configuration. Approach. Different arrangements have been simulated and compared in terms of spatial resolution and sensitivity. The chosen setup enables us to reach a good trade-off between a solid angle coverage and sufficient available space for the integration of additional components of the first design prototype of the SIRMIO platform. The possibility of moving the mouse holder inside the PET scanner furthermore allows for achieving the optimum placement of the irradiation area for all the possible tumor positions in the body of the mouse. The work also includes a study of the scintillator material where LYSO and GAGG are compared with a focus on the random coincidence noise due to the natural radioactivity of Lutetium in LYSO, justifying the choice of LYSO for the development of the final system. Main results. The best imaging performance can be achieved with a sub-millimeter spatial resolution and sensitivity of 10% in the center of the scanner, as verified in thorough simulations of point sources. The simulation of realistic irradiation scenarios of proton beams in PMMA targets with/without air gaps indicates the ability of the proposed PET system to detect range shifts down to 0.2 mm. Significance. The presented results support the choice of the identified optimal design for a novel spherical in-beam PET scanner which is currently under commissioning for application to small animal proton and light ion irradiation, and which might find also application, e.g. for biological image-guidance in x-ray irradiation.

Mapping Capillary Infiltration-Induced Potential in Water-Triggered Electric Generator Using an Electrical Probe Integrated Microscope.

Power generation from water-triggered capillary action in porous structures has recently geared extensive attention, offering the potential for generating electricity from ubiquitous water evaporation. However, conclusively establishing the nature of electrical generation and charge transfer is extremely challenging arising from the complicated aqueous solid-liquid interfacial phenomenon. Here, an electric probe-integrated microscope is developed to on-line monitor the correlation between water capillary action and potential values at any desired position of an active layer. With a probe spatial resolution reaching up to fifty micrometers, the internal factors prevailing over the potential distribution across the whole wet and dry regions are comprehensively identified. Further, the self-powered sensing capabilities of this integrated system are also demonstrated, including real-time monitoring of wind speed, environmental humidity, ionic strength, and inclination angle of generators. The combination of electric potential and chemical color indicator suggests that charge generation is likely correlated with ion-selective transport in the nanoporous channel during the water infiltration process. And unipolar ions (for instance protons) should be the dominant charge-transfer species. The work reveals the fundamental principles regulating charge generation/transfer during the water-triggered electric generation process.

Ion-Type Dependence of DNA Electronic Excitation in Water under Proton, α-Particle, and Carbon Ion Irradiation: A First-Principles Simulation Study.

Understanding how the electronic excitation of DNA changes in response to different high-energy particles is central to advancing ion beam cancer therapy and other related approaches, such as boron neutron capture therapy. While protons have been the predominant ions of choice in ion beam cancer therapy, heavier ions, particularly carbon ions, have drawn significant attention over the past decade. Carbon ions are expected to transfer larger amounts of energy according to linear response theory. However, molecular-level details of the electronic excitation under heavier ion irradiation remain unknown. In this work, we use real-time time-dependent density functional theory simulations to examine the quantum-mechanical details of DNA electronic excitations in water under proton, α-particle, and carbon ion irradiation. Our results show that the energy transfer does indeed increase for the heavier ions, while the excitation remains highly conformal. However, the increase in the energy transfer rate, measured by electronic stopping power, does not match the prediction by the linear response model, even when accounting for the velocity dependence of the irradiating ion's charge. The simulations also reveal that while the number of holes generated on DNA increases for heavier ions, the increase is only partially responsible for the larger stopping power. Larger numbers of highly energetic holes formed from the heavier ions also contribute significantly to the increased electronic stopping power.

Particle beam radiotherapy in the treatment of WHO grade 2 and 3 meningiomas: an early experience from Shanghai Proton and Heavy Ion Center.

To investigate the efficacy and safety of particle beam radiotherapy (PBRT) in the management of patients with WHO grade 2 and 3 meningiomas. Thirty-six consecutive and non-selected patients with WHO grade 2 (n = 28) and grade 3 (n = 8) meningiomas were treated at the Shanghai Proton and Heavy Ion Center, from May 2015 to March 2022. The median age of the cohort at PBRT was 48 years. There were 25 and 11 patients treated with PBRT in the setting of newly diagnosed diseases and progressive/recurrent diseases, respectively. PBRT was utilized as re-irradiation in 5 patients. Proton radiotherapy (PRT) and carbon-ion radiotherapy (CIRT), with a median dose of 60Gy-Equivalent (GyE), were provided to 30 and 6 patients, respectively. With a median follow-up of 23.3 months, the local control rates were 92.0%, 82.0%, and 82.0% at 1, 2, and 3 years for the entire cohort, respectively. Patients with WHO grade 2 meningiomas (100%, 94.1%, 94,1% at 1,2,3 years) had a much better local control than those with WHO grade 3 meningiomas (50%, 25%, 25% at 1,2,3 years; P < 0.001). Three patients, all with WHO grade 3 meningiomas, had deceased at the time of this analysis. Multivariate analyses revealed that WHO grade (grade 2 vs. 3) (p = 0.016) was a significant prognosticator for local control. No severe toxicities (G3 or above) were observed. Treatment-induced efficacy and toxicities to PBRT in WHO grade 2 and 3 meningiomas were both highly acceptable. Longer follow-up is needed to evaluate the long-term outcome in terms of disease control, survival, as well as potential late effects.

Potential impacts of hydrogen band EMIC waves on the ion velocity distributions: MMS observations

In this paper, the influence of the hydrogen (H+) band electromagnetic ion cyclotron (EMIC) waves on the hydrogen and helium velocity distributions has been studied. The hydrogen band EMIC waves have been investigated in the inner magnetosphere using the magnetospheric multiscale mission. The EMIC waves for the frequency range typical frequency have been frequently observed in the Earth's magnetosphere and have received considerable attention for energy transport across the magnetosphere. In this manuscript, we studied the velocity distribution of cold/hot proton and helium ions at different times of the event under consideration. For cold (1–600 eV) hydrogen ions, the velocity distribution is directly proportional to the growth rate of the EMIC wave, whereas the hot (1–40 keV) hydrogen ions have a ring distribution, which are not strongly influenced by the growth of EMIC waves like cold hydrogen ions, but the helium (1 eV–40 keV) ions are rarely influenced by EMIC waves.

Comparative analysis of the effectiveness of natural polymers and conventional space radiation shielding polymers in spacecraft for prolonged space expeditions

This paper investigates the shielding effectiveness of natural polymers, such as natural rubber and cotton, against space radiation. The results are compared with those of conventional shielding materials, such as polyethylene, Kevlar, and polycarbonate. Monte Carlo simulations were performed using a Geant4-based tool, Multi-layered shielding simulation software (MULASSIS). The shielding properties were studied using proton, alpha, and iron ions with energies of 1 GeV n−1. Online Tool for the Assessment of Radiation in Space (OLTARIS) is used for calculating the effective dose equivalent for the GCR spectra. Both studies showed that the natural polymers are just as effective as conventional space radiation shielding materials in terms of dose reduction. Natural rubber is found to be the most effective among the natural polymers. For 50 g cm−2 aluminum with 20 g cm−2 layer of chosen materials configuration, the effective dose equivalent values (mSv/day) for Polyethylene, Kevlar, Polycarbonate, Kapton, Epoxy, Dacron, and Vectran were 0.93, 1.08, 0.995, 1.056, 1.007, 1.031, and 1.042, respectively. The effective dose equivalent values (mSv/day) for natural polymers (natural rubber, cotton, jute, and silk) under the same conditions were 0.95, 1.004, 1.036, and 1.004, respectively. The challenges of utilizing radiation shields made of natural polymers are also briefly covered.

Biological Response of Chinese Hamster B14-150 Cells to Sequential Combined Exposure to Protons and 12C Ions.

Proton and ion radiation therapy, when used both as single radiation and in mixed radiation mode, have a number of advantages over the conventional γ-therapy that are determined by physical characteristics of accelerated particles. The paper presents the results of an in vitro study of the effectiveness of sequential exposures of Chinese hamster tumor cells B14-150 to proton (p) and 12C ion beams. We used 4 irradiation schemes differing by the sequence of exposure and the contribution of each radiation to the total dose. Synergism was shown for 12C ions dose contribution of 45% (taking into account the coefficient of relative biological efficiency) and the sequence 12C→p.

Physical, microstructural, and radiation energy absorption properties of recycled CRT-screen glass doped with Bi2O3

In this study, pristine TV-CRT screen glass (TVS) and those doped with 10% (TVS-Bi10) and 20% (TVS-Bi20) by weight of Bi2O3 were prepared and analyzed for their physical, microstructural, radiation dosimetry quantities, and shielding features. The glass samples were fabricated using the cold isostatic press method. The surface microstructure and the chemical composition of the glass ceramics were probed with the aid of the scanning electron microscopy-energy dispersive X-ray (SEM-EDX) system. Photon absorption and scattering quantities were estimated using standard procedures. The mean density values determined by Archimedes principle were calculated as 2.614, 2.788, and 3.056 gr/cm3 for the TVS, TVS-Bi10, and TVS-Bi20 samples, respectively. SEM images of samples showed that the increase in bismuth content increased sample crystallization and surface pores. The estimated mass energy absorption coefficients of the samples varied from 0.0177 to 11.7578 cm2/g for TVS, 0.0182–14.5218 cm2/g for TVS-Bi10, and 0.0187–17.7615 cm2/g for TVS-Bi20 for photon energies between 15 keV and 15 MeV. At 1 mm glass thickness and for 100 keV gamma rays, the dose rate was 13 MR/h, 17 MR/h, and 22 MR/h for TVS, TVS-Bi10, and TVS-Bi20, respectively. The mass stopping powers of electrons at 15 keV have values of 12.37 MeV cm2/g 12.21 MeV cm2/g, and 12.03 MeV cm2/g for TVS, TVS-Bi10, and TVS-Bi20, respectively. Generally, the ranges of the CPs were such that those of TVS > TVS-Bi10>TVS-Bi20. Bi2O3 increases the electron, proton, alpha particle, and carbon ion absorbing features of the TVS-BiX samples. Bi2O3 suppresses photon scattering, makes the TVS glass more sensitive to photon and charged particle interaction and absorption. The investigated glasses are useful for gamma-radiation, light, and heavy ion absorption and protection technology.

A TOPAS model for lens-based proton radiography

Objective. Proton Radiography can be used in conjunction with proton therapy for patient positioning, real-time estimates of stopping power, and adaptive therapy in regions with motion. The modeling capability shown here can be used to evaluate lens-based radiography as an instantaneous proton-based radiographic technique. The utilization of user-friendly Monte Carlo program TOPAS enables collaborators and other users to easily conduct medical- and therapy- based simulations of the Los Alamos Neutron Science Center (LANSCE). The resulting transport model is an open-source Monte Carlo package for simulations of proton and heavy ion therapy treatments and concurrent particle imaging. Approach. The four-quadrupole, magnetic lens system of the 800-MeV proton beamline at LANSCE is modeled in TOPAS. Several imaging and contrast objects were modelled to assess transmission at energies from 230–930 MeV and different levels of particle collimation. At different proton energies, the strength of the magnetic field was scaled according to βγ, the inverse product of particle relativistic velocity and particle momentum. Main results. Materials with high atomic number, Z, (gold, gallium, bone-equivalent) generated more contrast than materials with low-Z (water, lung-equivalent, adipose-equivalent). A 5-mrad collimator was beneficial for tissue-to-contrast agent contrast, while a 10-mrad collimator was best to distinguish between different high-Z materials. Assessment with a step-wedge phantom showed water-equivalent path length did not scale directly according to predicted values but could be mapped more accurately with calibration. Poor image quality was observed at low energies (230 MeV), but improved as proton energy increased, with sub-mm resolution at 630 MeV. Significance. Proton radiography becomes viable for shallow bone structures at 330 MeV, and for deeper structures at 630 MeV. Visibility improves with use of high-Z contrast agents. This modality may be particularly viable at carbon therapy centers with accelerators capable of delivering high energy protons and could be performed with carbon therapy.

Synergistic, extractive, and selective separation of light, medium, and heavy rare earth elements using Cyanex 572 and Alamine 336 from a chloride medium

In this study, the solvent extraction of rare earth elements (REEs) of different groups of light (LREE), medium (MREE), and heavy (HREE) from a chloride medium using the mixture of Cyanex 572 (cationic extractant, organophosphorus-based) and Alamine 336 (anionic extractant, amine-based) was studied. The results showed higher extraction efficiency for HREEs when sole Cyanex 572 was used. However, the addition of Alamine 336 to Cyanex 572 increased the extraction efficiency of LREEs and MREEs. The optimal volumetric ratio of Alamine 336 to Cyanex 572 for maximum extraction efficiency, under the studied conditions, was concluded to be 1:1 at a total extractant concentration of 30 % v/v. The synergistic enhancement factor when using this system for the extraction of LREEs and MREEs varied from 2 to 76 at different pH values and Alamine 336 ratios. To analyze the synergistic effect of the addition of Alamine 336 to Cyanex 572 on REE extraction, slope analysis and Fourier transform infrared spectroscopy measurement were performed. It was concluded that the role of Alamine 336 could be that of a proton ion extractor (released from the Cyanex 572 structure during REEs extraction) for REECl2+ complexes and that of a phase modifier for Cyanex 572 for REECl2+ complexes.

Trajectories of fear of progression in nasopharyngeal carcinoma patients receiving proton and heavy ion therapy.

The study examined the growth trajectory of fear of progression(FOP) in nasopharyngeal carcinoma (NPC) patients. In addition, sociodemographic and clinical variables of each trajectory class were analyzed. Two hundred sixteen NPC patients undergoing proton and heavy ion therapy were measured beginning (T0) and end of a 4-week proton and heavy ion therapy (T1), 3months (T2) and 6months (T3) after discharge. And data from the final 197 NPC patients were analyzed. NPC patients' FOP was investigated by the Fear of Progression Questionnaire-Short Form (FOP-Q-SF) form T0 to T3. SPSS and Mplus were used for statistical analysis. The LGMM was used to analyze the trajectory of FOP followed up over 6months after proton and heavy ion therapy. The logistic regression was utilized to compare the differences in sociodemographic and clinical characteristics of patients in different trajectory groups of FOP. One hundred ninety-seven NPC patients were analyzed. LGMM analysis showed that three-group trajectory solution was the best fitting (low-fear decline FOP (14.21%), the moderate-fear stable FOP(43.15%), and high-fear rising FOP (42.64%). Significant positive associations were found between age < 30years (β = 3.399, p = 0.023), with or without children (β = 3.1, p = 0.002), primary/recurrence (β = -6.196, p < 0.001), diagnosis < 3months (β = 4.435, p = 0.031), high school education (β = 2.98, p = 0.048), and high fear rising FOP. Patients who had moderate financial stress (β = 2.51, p = 0.041), with or without children (β = 1.564, p = 0.003), primary/recurrence (β = -2.578, p = 0.005), less than 30 radiotherapy times (β = 0.979, p = 0.046) tended to report significant moderate-fear stable FOP over time. 42.64% of the NPC patients showed high-fear rising FOP over the 6months after treatment. Age 18-30years, with or without children, relapsed, diagnosis < 3months, and high school education and reporting being a pessimist predicts higher FOP scores. Early identification of age 18-30years, with or without children, relapsed, diagnosis < 3months, and high school education might help to identify populations experiencing long-term FOP. Clinical teams responsible to develop the target interventions for management of FCR in clinical practice.

A qualitative exploration of fear of progression in patients with nasopharyngeal carcinoma treated with proton and heavy ion therapy.

To investigate fear of progression (FOP) in nasopharyngeal carcinoma (NPC) patients treated with proton and heavy ion therapy. Thirty NPC patients were selected for face-to-face semistructured interviews through purposive sampling while using the phenomenological approach in qualitative research. The interviews were transcribed, organized, and analyzed by applying Colaizzi's seven-step analysis. Seven themes were summarized, namely, illness uncertainty, trapped into insecurity (including four categories: insecurity about the possibility of discrimination, insecurity about the possibility of the inability to tolerate the pain of retreatment, insecurity about the difficulty of retreatment after recurrence, and insecurity of waiting for test results), hopelessness, loss, guilt toward children, enhancing tolerance toward family, and self-emotional comfort. We found that women with children and patients who experienced their first episode underwent significant FOP. Patients at the postgraduate level and above were more inclined to feel loss. The finding that respondents expressed is intense FOP while waiting for test results, which provides a reference for the analysis of the trajectory of FOP. Health care professions should be cognitively aware the importance of eliminating patients' uncertainty and insecurity about disease to enhance their positive experience in coping with cancer.

Interaction of Inner Heliosheath Ions with Electromagnetic Ion Cyclotron Waves

Inner heliosheath (IHS) ions are expected to be exposed to various waves, shocks, and turbulence, which can affect ion distributions and thus their charge-exchange rates with interstellar neutral atoms. This work addresses the potential significance of electromagnetic ion cyclotron (EMIC) waves under expected IHS conditions. From a kinetic dispersion relation, we find the possibility of frequent triggering of EMIC instability in the IHS. The threshold anisotropy of proton temperatures required for the instability is small, (T ⊥–T ∣∣)/T ∣∣ ≈ 0.1 or less, mainly due to high plasma β (ratio of the plasma to magnetic pressures). Numerical calculations on the scattering of ions (protons, He+, and He2+ with energy of 0.01–50 keV) based on two models for EMIC waves with a moderate intensity indicate significant scattering in the pitch angle (mostly a few tens of degrees) and energy (mostly a few tens of percent) although details depend on the energy and pitch angle of each species and adopted EMIC wave models. This occurs on a short timescale (<100 times the gyro-period of each ion species). Resonant scattering in a few to a few tens of keV (corresponding to the expected pickup ion energy in the IHS) is easily expected unless the wavenumber is too large. The scattering effect is distinguished among different species such that for lower gyrofrequency ions (He+ versus He2+and He2+ versus protons), the main scattering effect moves toward a lower energy domain. All these results imply continuous disturbance of ion distributions by possibly prevailing EMIC waves in the IHS.