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Fluorine 18-deoxyglucose is often used in Positron Emission Tomography devices. Positron Emission Tomography imaging is one of the useful tools which is used for cancer detection and its management. Positron Emission Tomography growth is limited due to problems that depend on the production of Fluorine-18. Imaging results are strongly depending on the information of nuclear reaction cross-section data. This study is presented to calculate different quantities such as stopping power, CSDA range, and simulated and distributed absorbed dose of Fluorine-18 in water. In order to access these goals, we use Geant4/Gate7 simulation and the theoretical Bethe-Bloch model. The results of this simulation and the theoretical model presented are in good agreement with each other. The important point of this paper is the presentation of a theoretical approach in order to the production of Fluorine-18 using protons generated through the main D(d;p) Tand side 3He(d;p)4He nuclear fusion reaction in which uses Helium-3 is catalyzed.

The application of radiation therapy (RT) in lung cancer has shown some exciting and sometimes disappointing advances in recent years. Protons compared with photons interact differently with human tissues, and can be used to improve patient care for suffering from lung cancer. A new strategy is the simultaneous injection of nanoparticles with proton radiation into the tumor which has been given over a decade to improve conventional RT. In this work, proton beam therapy (PBT) with gold nanoparticles (GNPs) is used as a part of a combination program to treat advanced localized lung cancers. This paper aims to develop the complex Geant4 model on the human lung and predict the distribution of absorbed dose in lung tumors during proton therapy without and with a high-Z injection of GNPs. Thus, the absorbed dose distribution in lung tumors for four modes such as (i) Bethe-Bloch’s relativistic quantum theory, (ii) GEANT4/ GATE7 simulation model, (iii) Hartree-Fock-Roothaan(HFR) wave functions, and the(vi) Bortfeld theoretical model without and with the injection of GNPs in predicted lung phantom are compared.

BackgroundPostmastectomy radiation therapy (PMRT) decreases the risk of locoregional recurrence and increases overall survival rates in patients with high-risk node positive breast cancer. While the number of breast cancer patients treated with proton-based PMRT has increased in recent years, there is limited data on the use of proton therapy in the postmastectomy with reconstruction setting. In this study, we compared acute toxicities and reconstructive complications in patients treated with proton-based and photon-based PMRT.MethodsA retrospective review of our institutional database was performed to identify breast cancer patients treated with mastectomy with implant or autologous reconstruction followed by PMRT from 2015 to 2020. Baseline clinical, disease, and treatment related factors were compared between the photon-based and proton-based PMRT groups. Early toxicity outcomes and reconstructive complications following PMRT were graded by the treating physician.ResultsA total of 11 patients treated with proton-based PMRT and 26 patients treated with photon-based PMRT were included with a median follow-up of 7.4 months (range, 0.7-33 months). Six patients (55%) in the proton group had a history of breast cancer (3 ipsilateral and 3 contralateral) and received previous RT 38 months ago (median, range 7-85). There was no significant difference in mean PMRT (p = 0.064) and boost dose (p = 0.608) between the two groups. Grade 2 skin toxicity was the most common acute toxicity in both groups (55% and 73% in the proton and photon group, respectively) (p = 0.077). Three patients (27%) in the proton group developed grade 3 skin toxicity. No Grade 4 acute toxicity was reported in either group. Reconstructive complications occurred in 4 patients (36%) in the proton group and 8 patients (31%) in photon group (p = 0.946).ConclusionsAcute skin toxicity remains the most frequent adverse event in both proton- and photon-based PMRT. In our study, reconstructive complications were not significantly higher in patients treated with proton- versus photon-based PMRT. Longer follow-up is warranted to assess late toxicities.

The production of a Z boson, decaying to two charged leptons, in association with jets in proton-proton collisions at a centre-of-mass energy of 13 TeV is measured. Data recorded with the CMS detector at the LHC are used that correspond to an integrated luminosity of 2.19 fb-1 . The cross section is measured as a function of the jet multiplicity and its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, which quantifies the hadronic activity, and the balance in transverse momentum between the reconstructed jet recoil and the Z boson. The measurements are compared with predictions from four different calculations. The first two merge matrix elements with different parton multiplicities in the final state and parton showering, one of which includes one-loop corrections. The third is a fixed-order calculation with next-to-next-to-leading order accuracy for the process with a Z boson and one parton in the final state. The fourth combines the fully differential next-to-next-to-leading order calculation of the process with no parton in the final state with next-to-next-to-leading logarithm resummation and parton showering.

Biomembranes, important building blocks of living organisms, are often exposed to large local fluctuations of pH and ionic strength. To capture changes in the membrane organization under such harsh conditions, we investigated the mobility and hydration of zwitterionic and anionic lipid bilayers upon elevated H3O+ and Ca2+ content by the time-dependent fluorescence shift (TDFS) technique. While the zwitterionic bilayers remain inert to lower pH and increased calcium concentrations, anionic membranes are responsive. Specifically, both bilayers enriched in phosphatidylserine (PS) and phosphatidylglycerol (PG) become dehydrated and rigidified at pH 4.0 compared to at pH 7.0. However, their reaction to the gradual Ca2+ increase in the acidic environment differs. While the PG bilayers exhibit strong rehydration and mild loosening of the carbonyl region, restoring membrane properties to those observed at pH 7.0, the PS bilayers remain dehydrated with minor bilayer stiffening. Molecular dynamics (MD) simulations support the strong binding of H3O+ to both PS and PG. Compared to PS, PG exhibits a weaker binding of Ca2+ also at a low pH. [ABSTRACT FROM AUTHOR]

The transmembrane transport of weak acid and base metabolites depends on the local pH conditions that affect the protonation status of the substrates and the availability of co-substrates, typically protons. Different protein designs ensure the attraction of substrates and co-substrates to the transporter entry sites. These include electrostatic surface charges on the transport proteins and complexation with seemingly transport-unrelated proteins that provide substrate and/or proton antenna, or enzymatically generate substrates in place. Such protein assemblies affect transport rates and directionality. The lipid membrane surface also collects and transfers protons. The complexity in the various systems enables adjustability and regulation in a given physiological or pathophysiological situation. This review describes experimentally shown principles in the attraction and facilitation of weak acid and base transport substrates, including monocarboxylates, ammonium, bicarbonate, and arsenite, plus protons as a co-substrate. [ABSTRACT FROM AUTHOR]

Purpose: The combined use of Bragg peak (BP) and shoot‐through (ST) beams has previously been shown to increase the normal tissue volume receiving FLASH dose rates while maintaining dose conformality compared to conventional intensity‐modulated proton therapy (IMPT) methods. However, the fixed beam optimization method has not considered the effects of beam orientation on the dose and dose rates. To maximize the proton FLASH effect, here, we incorporate dose rate objectives into our beam orientation optimization framework. Methods: From our previously developed group‐sparsity dose objectives, we add upper and lower dose rate terms using a surrogate dose‐averaged dose rate definition and solve using the fast‐iterative shrinking threshold algorithm. We compare the dosimetry for three head‐and‐neck cases between four techniques: (1) spread‐out BP IMPT (BP), (2) dose rate optimization using BP beams only (BP‐DR), (3) dose rate optimization using ST beams only (ST‐DR), and (4) dose rate optimization using combined BP and ST (BPST‐DR), with the goal of sparing organs at risk without loss of tumor coverage and maintaining high dose rate within a 10 mm region of interest (ROI) surrounding the clinical target volume (CTV). Results: For BP, BP‐DR, ST‐DR, and BPST‐DR, CTV homogeneity index and Dmax were found to be on average 0.886, 0.867, 0.687, and 0.936 and 107%, 109%, 135%, and 101% of prescription, respectively. Although ST‐DR plans were not able to meet dosimetric standards, BPST‐DR was able to match or improve either maximum or mean dose in the right submandibular gland, left and right parotids, constrictors, larynx, and spinal cord compared to BP plans. Volume of ROIs receiving greater than 40 Gy/s (Vγ0)${V_{\gamma 0}})$ was 51.0%, 91.4%, 95.5%, and 92.1% on average. Conclusions: The dose rate techniques, particularly BPST‐DR, were able to significantly increase dose rate without compromising physical dose compared with BP. Our algorithm efficiently selects beams that are optimal for both dose and dose rate. [ABSTRACT FROM AUTHOR]

• A systemic review of mediastinal lymphoma studies with dosimetric comparisons involving proton therapy was conducted, with 139 patients. • Proton therapy (FB or DIBH) may improve heart dose, with possibly lower lung, breast, and integral dose as compared to IMRT-DIBH. • Optimal choice of radiation technique depends on mediastinal distribution of disease and clinic access to advanced technologies. To systematically review all dosimetric studies investigating the impact of deep inspiration breath hold (DIBH) compared with free breathing (FB) in mediastinal lymphoma patients treated with proton therapy as compared to IMRT (intensity-modulated radiation therapy)-DIBH. We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline using the PubMed database to identify studies of mediastinal lymphoma patients with dosimetric comparisons of proton-FB and/or proton-DIBH with IMRT-DIBH. Parameters included mean heart (MHD), lung (MLD), and breast (MBD) doses, among other parameters. Case reports were excluded. Absolute differences in mean doses > 1 Gy between comparators were considered to be clinically meaningful. As of April 2021, eight studies fit these criteria (n = 8), with the following comparisons: proton-FB vs IMRT-DIBH (n = 5), proton-DIBH vs proton-FB (n = 5), and proton-DIBH vs IMRT-DIBH (n = 8). When comparing proton-FB with IMRT-DIBH in 5 studies, MHD was reduced with proton-FB in 2 studies, was similar (<1 Gy difference) in 2 studies, and increased in 1 study. On the other hand, MLD and MBD were reduced with proton-FB in 3 and 4 studies, respectively. When comparing proton-DIBH with proton-FB, MHD and MLD were reduced with proton DIBH in 4 and 3 studies, respectively, while MBD remained similar. Compared with IMRT-DIBH in 8 studies, proton-DIBH reduced the MHD in 7 studies and was similar in 1 study. Furthermore, MLD and MBD were reduced with proton-DIBH in 8 and 6 studies respectively. Integral dose was similar between proton-FB and proton-DIBH, and both were substantially lower than IMRT-DIBH. Accounting for heart, lung, breast, and integral dose, proton therapy (FB or DIBH) was superior to IMRT-DIBH. Proton-DIBH can lower dose to the lungs and heart even further compared with proton-FB, depending on disease location in the mediastinum, and organ-sparing and target coverage priorities. [ABSTRACT FROM AUTHOR]

Radiation therapy is a treatment that uses particles to destroy cancer cells, stop their development and preserve the healthy organs around the tumour. A precise treatment requires the implementation of several processes, in particular, the determination of the correct ballistics, thus the effect of the particles on the deposited dose. Indeed, one of the most important steps in this evaluation is to calculate the deposited dose in a water phantom with resolution (20 × 20 × 30) cm3 using four therapeutic particles namely electromagnetic radiation "photons", negatively charged stable elementary particle "electrons", neutral particles "neutrons", and heavy elementary particle with a positive charge "protons" with nominal energies from 2 to 20 MeV with constant steps of 2 MeV were simulated in the first place. In the second place, we calculated the deposited dose of the protons beams for therapeutic energies ranging from 60 to 340 MeV with a beam of 100 000 particles produced by a primary radioactive source using the Monte Carlo simulation platform GEANT4. In our paper, we evaluate the effect of four therapeutic particles in the same environment assuring the accurate computation of delivered dose on the treatment plan and subtracting significant discrepancies in terms of deposited dose between particles. [ABSTRACT FROM AUTHOR]

Introduction: Radiation-induced oxygen depletion in tissue is assumed as a contributor to the FLASH sparing effects. In this study, we simulated the heterogeneous oxygen depletion in the tissue surrounding the vessels and calculated the proton FLASH effective-dose-modifying factor (FEDMF), which could be used for biology-based treatment planning. Methods: The dose and dose-weighted linear energy transfer (LET) of a small animal proton irradiator was simulated with Monte Carlo simulation. We deployed a parabolic partial differential equation to account for the generalized radiation oxygen depletion, tissue oxygen diffusion, and metabolic processes to investigate oxygen distribution in 1D, 2D, and 3D solution space. Dose and dose rates, particle LET, vasculature spacing, and blood oxygen supplies were considered. Using a similar framework for the hypoxic reduction factor (HRF) developed previously, the FEDMF was derived as the ratio of the cumulative normoxic-equivalent dose (CNED) between CONV and UHDR deliveries. Results: Dynamic equilibrium between oxygen diffusion and tissue metabolism can result in tissue hypoxia. The hypoxic region displayed enhanced radioresistance and resulted in lower CNED under UHDR deliveries. In 1D solution, comparing 15 Gy proton dose delivered at CONV 0.5 and UHDR 125 Gy/s, 61.5% of the tissue exhibited ≥20% FEDMF at 175 mm vasculature spacing and 18.9 mM boundary condition. This percentage reduced to 34.5% and 0% for 8 and 2 Gy deliveries, respectively. Similar trends were observed in the 3D solution space. The FLASH versus CONV differential effect remained at larger vasculature spacings. A higher FLASH dose rate showed an increased region with ≥20% FEDMF. A higher LET near the proton Bragg peak region did not appear to alter the FLASH effect. Conclusion: We developed 1D, 2D, and 3D oxygen depletion simulation process to obtain the dynamic HRF and derive the proton FEDMF related to the dose delivery parameters and the local tissue vasculature information. The phenomenological model can be used to simulate or predict FLASH effects based on tissue vasculature and oxygen concentration data obtained from other experiments. [ABSTRACT FROM AUTHOR]

The article proposes to consider two fundamentally new ways of accelerating charged particles: linear acceleration (LA) of protons on a backward wave (Professor Bogomolov's Accelerator) and wake acceleration of electrons using a proton driver in the Large Hadron Collider (AWAKE project). [ABSTRACT FROM AUTHOR]

Proton transport is involved in many biological processes, such as viral replication and enzymatic catalysis. However, one-way transmission is the premise of the realization of the above functions. Actually, the unidirectional transport of protons is significant not only for biology but also for practical applications. Herein, inspired by the influenza A M2 channel, a sub-nanoporous proton transport membrane was constructed by layer-by-layer assembly of two oppositely charged pillar-[n]-arenes with sub-nanometer cavities. A good selectivity of the proton transport membranes to protons was achieved by exploiting the size effect of sub-nanometer pores. And the proton transport membrane has a transport capacity of 459 μM·m–2·h–1 for protons. For nanofluidic diodes, the construction of the sub-nanopore proton transport membrane was very meaningful. For energy conversion applications such as catalytic transformations, although the flux cannot meet the application in these fields, the development of this membrane provides an idea for it. What is more, it can help deepen the understanding of the relationship between sub-nanostructure and function. [ABSTRACT FROM AUTHOR]

Simple Summary: Clival chordoma is a rare malignant tumor that commonly arises near the center of the brain. In 2013, multidisciplinary team was introduced in our facility to manage clival chordoma effectively. We analyzed its effect by comparing the outcomes of patients from "before 2013" (19 patients) and "after 2013" (39 patients). After 2013, the endoscopic endonasal approach was more commonly used (90%; "before 2013", 32%) to achieve gross to near total resections (64%; "before 2013", 16%) with less post-operative new cranial nerve deficits (3%; "before 2013", 32%). Gross to near total resection was associated with less recurrence (hazard ratio, 0.31; 95% confidence interval, 0.11 to 0.91; p = 0.033). The multidisciplinary team led to improved tumor resection rate, less tumor recurrence rate, and less morbidity. The management of clival chordoma in our group shifted around 2013 to mostly endoscopic, and proton beam was introduced for our multidisciplinary team. Consecutive patients who had surgical resection from 1987 to 2021 were reviewed. A total of 58 patients (39 patients after 2013) were analyzed. The mean tumor size was 3.7 cm, and the most common location was the upper clivus (43%). Compared to before 2013, after 2013, the endoscopic endonasal approach was more common (90%, p < 0.001), and more gross or near total resections (64%, p = 0.002) were attained. Ten cases (17%) were revision surgeries referred from elsewhere, and three cases (5%) underwent additional surgery elsewhere before adjuvant radiation. The postoperative cerebrospinal fluid leak occurred in 7%. Post-operative new cranial nerve deficits occurred in 32% before 2013, compared to 2.6% after 2013 (p = 0.004). For cases before 2013, 10 patients (53%) recurred during the median follow-up of 144 months (mean, 142 months), whereas for cases after 2013, seven patients (18%) recurred with a median follow-up of 35 months (mean, 42 months). 5-year progression-free survival was 58%, and 5-year overall survival was 87%. A specialized multidisciplinary team improved the resection rate compared to a historical cohort with an excellent morbidity profile. [ABSTRACT FROM AUTHOR]

The III-V binary compound semiconductor is considered to be an appealing candidate for future complementary metal oxide semiconductor applications and the most promising silicon substitute in terms of high electron mobility. In this study, the authors used the Monte Carlo simulation software Geant4 and the data analysis tool Python to comprehensively examine the interaction between protons with a wide range of energy and III-V binary compound semiconductors. This work focus on the radiation responses of 11 kinds of III-V materials—AlAs, AlP, AlSb, GaAs, GaN, GaP, GaSb, InAs, InN, InP, and InSb—with silicon as a reference. Energy straggling, secondary ion generation, and energy distribution in the sensitive layer were represented in each simulation of the incident protons. Information about the distributions of the linear energy transfer of the secondary ions and energy deposition was acquired through data analysis. Finally, the impact of the material species on the single-event upset responses triggered by the direct ionization and the nuclear reaction mechanisms at different critical charges were investigated. [ABSTRACT FROM AUTHOR]

New series of YBCO ceramics samples doping with different oxides such as SiO2, WO3, Al2O3, and TiO2 were fabricated to study the ionizing radiation shielding properties. The structure and morphology were explored by X-ray diffraction (XRD) and scanning electron microscope (SEM). The shielding properties were investigated experimentally and theoretically to check the validity of the results. The investigated radiation shielding properties include the proton, neutron, and gamma-ray. The XRD results show the orthorhombic structure for all ceramics without any additional peaks related to WO3, SiO2, TiO2, and Al2O3. At the same time, the SEM results appear to have a significant differentiation in the granular behavior of all ceramics surfaces. The incorporation of WO3 to YBCO enhanced the ceramic density, whereas the addition of different oxides reduced the density for ceramic samples. This variation in density changed the radiation shielding results. The sample containing WO3 (YBCO-W) gives us better results in radiation shielding properties for gamma and neutron; the sample having Al2O3 (YBCO-Al) is superior in shielding results for charged particles. Finally, the possibility to use YBCO with various oxides in different ionizing radiation shielding fields can be concluded. [ABSTRACT FROM AUTHOR]

Mutations in the H+(OH-) conductor SLC4A11 result in corneal endothelial dystrophy. In previous studies using mouse Slc4a11, we showed that the pK value that governs the intracellular pH dependence of SLC4A11 (pKi) is influenced by extracellular pH (pHe). We also showed that some mutations result in acidic or alkaline shifts in pKi, indicating that the pH dependence of SLC4A11 is important for physiological function. An R125H mutant, located in the cytosolic amino terminus of SLC4A11, apparently causes a complete loss of function, yet the anion transport inhibitor 4,40-diisothiocyano-2,20-stilbenedisulfonic acid (DIDS) can partially rescue SLC4A11/R125H activity. In the present study we set out to determine whether the effect of R125H is explained by an extreme shift in pKi. In Xenopus oocytes, we measured SLC4A11-mediated H+(OH-) conductance while monitoring pHi. We find that 1) the human corneal variant SLC4A11-B has a more acidic pKi than mouse Slc4a11, likely due to the presence of an NH2-terminal appendage; 2) pKi for human SLC4A11 is acid-shifted by raising pHe to 10.00; and 3) R125H and R804H mutants mediate substantial H+(OH-) conductances at pHe = 10.00, with pKi shifted into the wild-type range. These data suggest that the defect in each is a shift in pKi at physiological pHe, brought about by a disconnection in the mechanisms by which pHe influences pKi. Using de novo modeling, we show that R125 is located at the cytosolic dimer interface and suggest that this interface is critical for relaying the influence of pHe on the external face of the transmembrane domain to the intracellular, pKi-determining regions. [ABSTRACT FROM AUTHOR]

Background: Proton therapy (PT) has potential advantages in pediatric Hodgkin lymphoma (pHL). However, there are limited data on PT, specifically to infradiaphragmatic targets. We report on PT planning details, doses achieved to organs at risk (OARs), and clinical and toxicity outcomes for patients with pHL who received PT to infradiaphragmatic regions., Methods: This is a retrospective study including patients treated between 2011 and 2022. Demographic and clinical factors were collected, and toxicity was reported using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Dosimetric and clinical factors associated with key outcomes were assessed via Cox regression. Photon plans were generated for all patients, and the paired t-tests or Wilcoxon signed rank sum tests were used for dosimetric comparisons., Results: Twenty-one patients comprising 22 PT courses were included. Median follow-up was 5.0 years, and mean age was 14.2 years. Median dose was 21 Gray equivalent (GyE) over 14 fractions. Top acute grade 1 (G1) toxicities included fatigue (59%) and anorexia (36%). Rates of acute G2 and G3+ toxicity were 18% and 0%, respectively. After PT, no local or marginal failures occurred. Five percent experienced disease progression, who were all successfully salvaged, and all patients were alive and disease-free at last follow-up. No secondary malignancies developed. Compared to photon radiotherapy, PT achieved significantly lower doses to the bowels, stomach, spleen, pancreatic tail, liver, kidneys, and pelvic bones., Conclusions: PT is well-tolerated and leads to excellent oncologic and toxicity outcomes with long-term follow-up. PT confers dosimetric advantages when compared to photons., (© 2024 The Author(s). Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Solar-energy-driven photocatalytic CO 2 reduction by H 2 O to high-valuable carbon-containing chemicals has become one of the greatest concerns in both scientific and industrial communities, due to its potential in solving energy and environmental problems. However, efficiency of photocatalytic CO 2 reduction by H 2 O is still far below the needs of large-scale applications. The reduction efficiency is closely related to ability of photocatalysts in absorbing visible light which is the main part of sunlight (44 %), separating photogenerated electron-hole pairs, adsorbing CO 2 and producing protons for reducing CO 2 . Thus, photocatalysts with enhanced visible light absorption, electron-hole separation, CO 2 adsorption and proton production are highly desired. Herein, we aim to provide a picture of recent progresses in improving ability of photocatalysts in visible light absorption, electron-hole separation, CO 2 adsorption and proton production, and give an outlook for future researches associated with photocatalytic CO 2 reduction by H 2 O., (© 2024 Wiley-VCH GmbH.)

Physical reservoirs are a promising approach for realizing high-performance artificial intelligence devices utilizing physical devices. Although nonlinear interfered spin-wave multi-detection exhibits high nonlinearity and the ability to map in high dimensional feature space, it does not have sufficient performance to process time-series data precisely. Herein, development of an iono-magnonic reservoir by combining such interfered spin wave multi-detection and ion-gating involving protonation-induced redox reaction triggered by the application of voltage is reported. This study is the first to report the manipulation of the propagating spin wave property by ion-gating and the application of the same to physical reservoir computing. The subject iono-magnonic reservoir can generate various reservoir states in a single homogenous medium by utilizing a spin wave property modulated by ion-gating. Utilizing the strong nonlinearity resulting from chaos, the reservoir shows good computational performance in completing the Mackey-Glass chaotic time-series prediction task, and the performance is comparable to that exhibited by simulated neural networks., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Introduction: Ion therapies have an increased relative biological effectiveness (RBE) compared to X-rays, but this remains poorly quantified across different radiation qualities. Mechanistic models that simulate DNA damage and repair after irradiation could be used to help better quantify RBE. However, there is large variation in model design with the simulation detail and number of parameters required to accurately predict key biological endpoints remaining unclear. This work investigated damage models with varying detail to determine how different model features impact the predicted DNA damage.&#xD;&#xD;Methods: Damage models of reducing detail were designed in TOPAS-nBio and Medras investigating the inclusion of chemistry, realistic nuclear geometries, single strand break damage, and track structure. The nucleus models were irradiated with 1 Gy of protons across a range of linear energy transfers (LETs). Damage parameters in the models with reduced levels of simulation detail were fit to proton double strand break (DSB) yield predicted by the most detailed model. Irradiation of the optimised models with a range of radiation qualities was then simulated, before undergoing repair in the Medras biological response model.&#xD;&#xD;Results: Simplified damage models optimised to proton exposures predicted similar trends in DNA damage across radiation qualities. On average across radiation qualities, the simplified models experienced an 8% variation in double strand break (DSB) yield but a larger 28% variation in chromosome aberrations. Aberration differences became more prominent at higher LETs, with model features having an increasing impact on the distribution and therefore misrepair of DSBs. However, overall trends remained similar with better agreement likely achievable through repair model optimisation. &#xD;&#xD;Conclusion: Several model simplifications could be made without compromising key damage yield predictions, although changes in damage complexity and distribution were observed. This suggests simpler, more efficient models may be sufficient for initial radiation damage comparisons, if validated against experimental data.&#xD., (Creative Commons Attribution license.)

Maiko Kadowaki,1,&ast; Koichi Sato,2,&ast; Hisashi Kamio,3 Makoto Kumagai,3 Rikishi Sato,3 Takafumi Nyui,3 Yukihiro Umeda,1 Yuko Waseda,1 Masaki Anzai,1 Haruka Aoki-Saito,4 Yasuhiko Koga,4 Takeshi Hisada,5 Hideaki Tomura,6 Fumikazu Okajima,3 Tamotsu Ishizuka1 1Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan; 2Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebeshi, 371-8512, Japan; 3Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan; 4Department of Respiratory Medicine, Gunma University Graduate School of Medicine, Maebeshi, 371-8511, Japan; 5Gunma University Graduate School of Health Sciences, Maebeshi, 371-8514, Japan; 6Laboratory of Cell Signaling Regulation, Division of Life Science, School of Agriculture, Meiji University, Kawasaki, 214-8571, Japan&ast;These authors contributed equally to this workCorrespondence: Tamotsu IshizukaThird Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuoka-Shimoaizuki, Eiheiji, Fukui, 910-1193, JapanTel +81-776-61-8355Fax +81-776-61-8111Email tamotsui@u-fukui.ac.jpPurpose: Human bronchial smooth muscle cells (BSMCs) contribute to airway obstruction and hyperresponsiveness in patients with bronchial asthma. BSMCs also generate cytokines and matricellular proteins in response to extracellular acidification through the ovarian cancer G protein-coupled receptor 1 (OGR1). Cobalt (Co) and nickel (Ni) are occupational agents, which cause occupational asthma. We examined the effects of Co and Ni on interleukin-6 (IL-6) secretion by human BSMCs because these metals may act as ligands of OGR1.Methods: Human BSMCs were incubated in Dulbecco’s Modified Eagle Medium (DMEM) containing 0.1% bovine serum albumin (BSA) (0.1% BSA-DMEM) for 16 hours and stimulated for the indicated time by exchanging the medium with 0.1% BSA-DMEM containing any of the metals or pH-adjusted 0.1% BSA-DMEM. IL-6 mRNA expression was quantified via reverse transcription polymerase chain reaction (RT-PCR) using the real-time TaqMan technology. IL-6 was measured using an enzyme-linked immunosorbent assay. Dexamethasone (DEX) was added 30 minutes before each stimulation. To knock down the expression of OGR1 in BSMCs, small interfering RNA (siRNA) targeting OGR1 (OGR1-siRNA) was transfected to the cells and non-targeting siRNA (NT-siRNA) was used as a control.Results: Co and Ni both significantly increased IL-6 secretion in human BSMCs at 300 μM. This significant increase in IL-6 mRNA expression was observed 5 hours after stimulation. BSMCs transfected with OGR1-siRNA produced less IL-6 than BSMCs transfected with NT-siRNA in response to either Co or Ni stimulation. DEX inhibited Co- and Ni-stimulated IL-6 secretion by human BSMCs as well as pH 6.3-stimulated IL-6 secretion in a dose-dependent manner. DEX did not decrease phosphorylation of ERK1/2, p38 MAP kinase, and NF-κB p65 induced by either Co or Ni stimulation.Conclusion: Co and Ni induce secretion of IL-6 in human BSMCs through activation of OGR1. Co- and Ni-stimulated IL-6 secretion is inhibited by DEX.Keywords: cobalt, nickel, proton, cytokine, glucocorticoid, asthma

Purpose: Optic nerves are part of the craniospinal irradiation (CSI) target volume. Modern radiotherapy techniques achieve highly conformal target doses while avoiding organs-at-risk such as the lens. The magnitude of eye movement and its influence on CSI target- and avoidance volumes are unclear. We aimed to evaluate the movement-range of lenses and optic nerves and its influence on dose distribution of several planning techniques. Methods: Ten volunteers underwent MRI scans in various gaze directions (neutral, left, right, cranial, caudal). Lenses, orbital optic nerves, optic discs and CSI target volumes were delineated. 36-Gy cranial irradiation plans were constructed on synthetic CT images in neutral gaze, with Volumetric Modulated Arc Therapy, pencil-beam scanning proton therapy, and 3D-conventional photons. Movement-amplitudes of lenses and optic discs were analyzed, and influence of gaze direction on lens and orbital optic nerve dose distribution. Results: Mean eye structures’ shift from neutral position was greatest in caudal gaze; −5.8±1.2 mm (±SD) for lenses and 7.0±2.0 mm for optic discs. In 3D-conventional plans, caudal gaze decreased Mean Lens Dose (MLD). In VMAT and proton plans, eye movements mainly increased MLD and diminished D98 orbital optic nerve (D98OON) coverage; mean MLD increased up to 5.5 Gy [total ΔMLD range −8.1 to 10.0 Gy], and mean D98OON decreased up to 3.3 Gy [total ΔD98OON range −13.6 to 1.2 Gy]. VMAT plans optimized for optic disc Internal Target Volume and lens Planning organ-at-Risk Volume resulted in higher MLD over gaze directions. D98OON became ≥95% of prescribed dose over 95/100 evaluated gaze directions, while all-gaze bilateral D98OON significantly changed in 1 of 10 volunteers. Conclusion: With modern CSI techniques, eye movements result in higher lens doses and a mean detriment for orbital optic nerve dose coverage of

Oxidative stress is a major risk factor that causes osteocyte cell death and bone loss. Prior studies primarily focus on the function of cell surface expressed Cx43 channels. Here, we reported a new role of mitochondrial Cx43 (mtCx43) and hemichannels (HCs) in modulating mitochondria homeostasis and function in bone osteocytes under oxidative stress. In murine long bone osteocyte-Y4 cells, the translocation of Cx43 to mitochondria was increased under H2O2-induced oxidative stress. H2O2 increased the mtCx43 level accompanied by elevated mtCx43 HC activity, determined by dye uptake assay. Cx43 knockdown (KD) by the CRISPR-Cas9 lentivirus system resulted in impairment of mitochondrial function, primarily manifested as decreased ATP production. Cx43 KD had reduced intracellular reactive oxidative species levels and mitochondrial membrane potential. Additionally, live-cell imaging results demonstrated that the proton flux was dependent on mtCx43 HCs because its activity was specifically inhibited by an antibody targeting Cx43 C-terminus. The co-localization and interaction of mtCx43 and ATP synthase subunit F (ATP5J2) were confirmed by Förster resonance energy transfer and a protein pull-down assay. Together, our study suggests that mtCx43 HCs regulate mitochondrial ATP generation by mediating K+, H+, and ATP transfer across the mitochondrial inner membrane and the interaction with mitochondrial ATP synthase, contributing to the maintenance of mitochondrial redox levels in response to oxidative stress.

We extend the two-centre wave-packet convergent close-coupling approach to doubly differential ionisation in proton collisions with H2 to intermediate projectile energies. The results for the doubly differential cross section at projectile energies from 48 to 200 keV are presented as a function of the energy and angle of emitted electrons. We consider a wide range of emission angles from 10 to 160∘, and compare our results to experimental data, where available. Excellent agreement between the presented results and the experimental data was found, especially for emission angles less than 130∘. For very large backward emission angles our calculations tended to slightly overestimate the experimental data when energetic electrons are ejected and the doubly differential cross section is very small. This discrepancy may be due to the large uncertainties in the experimental data in this region and the model target description. Overall, the present results show significant improvement upon currently available theoretical results and provide a consistently accurate description of this process across a wide range of incident energies.

Antioxidants in cancer therapy have been a hot topic in the medical field for 20 years. Antioxidants are able to reduce the risk of cancer formation by neutralizing free radicals. Protons (H+) and molecular hydrogen (H2) interact in the cell and are essential in a wide variety of processes. The antioxidant, anti-inflammatory, and antiapoptotic effects of H2 have been studied in numerous experimental and clinical studies. Experimental data indicate that H2 is an antitumor agent in the treatment of glioblastoma (GBM). In vivo H2 inhalation could suppress the growth of GBM tumors, thereby extending the survival of mice with GBM. The sphere-forming ability of glioma cells was suppressed by hydrogen treatment. In addition, H2 treatment also suppressed the migration, invasion, and colony-forming ability of glioma cells. Proton therapy and proton beam radiotherapy offer some advantages over other modern conformal photon-based therapies when used in the treatment of central nervous system malignancies.

Quinone compounds, which are capable of accommodating proton (H+), are emerging electrodes in aqueous batteries. However, the storage mechanism of proton in quinone compounds is less known and the energy/power density of quinone‐based proton battery is still limited. Here we design a series of quinone anodes and study their electrochemical properties in acidic electrolyte, in which tetramethylquinone (TMBQ) delivers a high capacity of 300 mAh g−1 with an extremely low polarization of 20 mV at 1 C, and maintains over 50 % theoretical capacity in less than 16 seconds. The fast kinetics of TMBQ is attributed to the continuous H+ migration channel, high H+ diffusion coefficient (10−6 cm2 s−1), and low H+ migration energy barrier (0.26 eV). When coupling with MnO2 cathode, the battery shows a long lifespan of 4000 cycles with a capacity retention of 77 % at 5 C. This study reveals the proton transport in quinone‐electrodes and offers new insights to design advanced aqueous batteries. [ABSTRACT FROM AUTHOR]

Objective. This study aims at comparing dosimetric parameters of 126 MeV antiprotons and protons using microdosimetric approach. Approach. Microdosimetric distributions of 126 MeV proton and antiproton beams at 1 ÎĽ m site size are calculated using the Monte Carlo-based FLUKA code. The distributions are calculated at various depths along the central axis in water phantom as well as at different off-axis locations. The study also includes calculations of secondary radiations produced by antiprotons and protons. Mean quality factor, Q ÂŻ is calculated using the ICRP 60 and ICRU 40 recommendations. The Relative Biological Effectiveness (RBE) of HSG tumour cell at 10% survival level is calculated based on Microdosimetric Kinetic Model. Main results. Q ÂŻ I C R P , Q ÂŻ ICRU and RBE for antiprotons are higher by a factor of about 3.60, 3.41 and 1.24, respectively, at Bragg-peak and higher by a factor of about 1.41, 1.76 and 1.05, respectively, at plateau region of depth-dose profile when compared to protons. At 15 cm depth along the central axis, Q ÂŻ ICRP , Q ÂŻ ICRU and RBE for protons are higher by a factor of about 1.42, 1.66 and 1.26, respectively, when compared to antiprotons. At the off-axis distance (Ld) of 6 cm (at 11.5 cm depth in water), Q ÂŻ ICRP and Q ÂŻ ICRU of protons are higher than that of antiproton whereas the trend is opposite at off-axis distance of 4 cm. At Ld= 4 cm (at 11.5 cm depth in water), RBE of antiprotons is higher by about 4% than protons whereas at Ld = 6 cm, RBE of protons is higher by about 13% than antiprotons. Significance. The study shows that antiproton radiotherapy is advantageous as compared to protons considering enhancements in the absorbed dose and RBE-weighed dose values at the Bragg-peak. [ABSTRACT FROM AUTHOR]

The transport behaviors of proton into nanoporous materials were investigated using different Monte Carlo simulation codes such as GEANT4, Deeper and SRIM. The results indicated that porous structure could enhance the proton scattering effects due to a higher specific surface area and more boundaries. The existence of voids can deepen and widen the proton distribution in the targets due to relatively lower apparent density. Thus, the incident protons would transport deeper and form a wider Bragg peak in the end of the range, as the target materials are in a higher porosity state and/or have a larger pore size. The existence of voids also causes the local inhomogeneity of proton/energy distribution in micro/nano scales. As compared, the commonly used SRIM code can only be used to estimate roughly the incident proton range in nanoporous materials, based on a homogeneous apparent density equivalence rule. Moreover, the estimated errors of the proton range tend to increase with the porosity. The Deeper code (designed for evaluation of radiation effects of nuclear materials) can be used to simulate the transport behaviors of protons or heavy ions in a real porous material with porosity smaller than 52.3% due to its modeling difficulty, while the GEANT4 code has shown advantages in that it is suitable and has been proven to simulate proton transportation in nanoporous materials with porosity in its full range of 0~100%. The GEANT4 simulation results are proved consistent with the experimental data, implying compatibility to deal with ion transportation into homogeneously nanoporous materials. [ABSTRACT FROM AUTHOR]

Jupiter is known to have a complex magnetosphere containing energetic (above 10s of keV) electrons, protons, and heavy ions. However, a global distribution of these energetic particles is not fully understood before the era of the polar‐orbiting Juno mission. In this study, we focus on the energetic proton distribution at M < 50 by taking advantage of Juno's measurement covering various magnetic latitudes and M‐shells, and find that energetic proton fluxes are higher off‐equator than that near the equator at M > ∼20, and become comparable or lower at high latitudes than those near the equator at low M‐shells. Pitch angle distributions of energetic protons are field‐aligned, isotropic, and weak pancake‐like from high to low M‐shells. Proton phase space density shows a weak M‐shell dependence at M > 30 and a large positive slope at M < 30, suggesting their potential source and loss processes. Plain Language Summary: Jupiter has a strongly magnetized magnetosphere, which traps electrons and ions with a broad energy range. Before the arrival of Juno at Jupiter, there were limited observations of particles at high latitudes. By taking advantage of high‐quality energetic proton observations from Juno, we evaluate the global distribution of energetic protons at Jupiter. The statistical results suggest that energetic proton flux is mostly comparable or even higher at high latitudes compared to that near the equator, which is consistent with their equatorial pitch angle distributions showing mostly field‐aligned and isotropic, except for a weak pancake feature at low M‐shells. Furthermore, the radial proton phase space density profile shows a weak M‐shell dependence at M > 30 and a large positive slope at M < 30. The underlying mechanisms related to the observed statistical pattern of proton distributions are discussed. Key Points: A statistical survey of energetic proton flux at various M‐shells (M < 50) and magnetic latitudes is performed using Juno observationsPitch angle distribution of energetic protons is mostly field aligned at M > 25 and tends to become pancake‐shaped at smaller M‐shellsPhase space density of equatorial protons increases with increasing M‐shell at M ∼7–30 and keeps almost the same beyond M ∼ 30 [ABSTRACT FROM AUTHOR]

Purpose: To investigate DNA double strand breaks (DSBs) induced by therapeutic proton beams in plateau and Bragg peak to demonstrate DSB induction due to the higher LET in the Bragg peak. Materials and Methods: pUC19 plasmid DNA samples were irradiated to doses of 1000 and 3000 Gy on a Mevion S250i proton system with a monoenergetic, 110 MeV, proton beam at depths of 2 and 9.4 cm, corresponding to a position on the plateau and distal Bragg peak of the beam, respectively. The irradiated DNA samples were imaged by atomic force microscopy for visualization of individual DNA molecules, either broken or intact, and quantification of the DNA fragment length distributions for each of the irradiated samples. Percentage of the broken DNA and average number of DSBs per DNA molecule were obtained. Results: Compared to irradiation effects in the plateau region, DNA irradiated at the Bragg peak sustained more breakage at the same dose, yielding more short DNA fragments and higher numbers of DSB per DNA molecule. Conclusion: The higher LET of proton beams at the Bragg peak results in more densely distributed DNA DSBs, which supports an underlying mechanism for the increased cell killing by protons at the Bragg peak. [ABSTRACT FROM AUTHOR]

Local acidification is a common feature of many disease processes such as inflammation, infarction, or solid tumor growth. Acidic pH is not merely a sequela of disease but contributes to recruitment and regulation of immune cells, modifies metabolism of parenchymal, immune and tumor cells, modulates fibrosis, vascular permeability, oxygen availability, and consumption, invasiveness of tumor cells, and impacts on cell survival. Thus, multiple pH-sensing mechanisms must exist in cells involved in these processes. These pH sensors play important roles in normal physiology and pathophysiology, and hence might be attractive targets for pharmacological interventions. Among the pH-sensing mechanisms, OGR1 (GPR68), GPR4 (GPR4), and TDAG8 (GPR65) have emerged as important molecules. These G protein-coupled receptors are widely expressed, upregulated in inflammation and tumors, sense changes in extracellular pH in the range between pH 8 and 6, and are involved in modulating key processes in inflammation, tumor biology, and fibrosis. This review discusses key features of these receptors and highlights important disease states and pathways affected by their activity. [ABSTRACT FROM AUTHOR]

Background: The present study aimed to investigate the dosimetric impact of metal stent for photon and proton treatment plans in hepatocellular carcinoma.Methods: With computed tomography data of a water-equivalent solid phantom, dose perturbation caused by a metal stent included in the photon and proton treatment of hepatocellular carcinoma was evaluated by comparing Eclipse and RayStation treatment planning system (TPS) to a Monte Carlo (MC) based dose calculator. Photon and proton plans were created with anterior-posterior/posterior-anterior (AP/PA) fields using a 6 MV beam and AP/PA fields of a wobbling beam using 150 MeV and a 10 cm ridge filter. The difference in dose distributions and dosimetric parameters were compared depending on the stent's positions (the bile duct (GB) and intestinal tract (GI)) and angles (0°, 45°, and 90°). Additionally, the dose variation in the target volume including the stent was comparatively evaluated through dose volume histogram (DVH) analysis. And the comparison of clinical cases was carried out in the same way.Results: Percentage differences in the dosimetric parameters calculated by MC ranged from - 7.0 to 3.9% for the photon plan and - 33.7 to 4.3% for the proton plan, depending on the angle at which the GB and GI stents were placed, compared to those without the stent. The maximum difference was observed at the minimum dose (Dmin), which was observed in both photon and proton plans in the GB and GI stents deployed at a 90° incidence angle. The parameter differences were greater in the proton plan than in photon plan. The target volume showed various dose variations depending on positions and angles of stent for both beams. Compared with no-stent, the doses within the target volume containing the GI and GB stents for the photon beam were overestimated in the high-dose area at 0°, nearly equal within 1% at 45°, and underestimated at 90°. These doses to the proton beam were underestimated at all angles, and the amount of underdose to the target volume increased with an increase in the stent angle. However, the difference was significantly greater with the proton plan than the photon plan.Conclusions: Dose perturbations within the target volume due to the presence of the metal stent were not observed in the TPS calculations for photon and proton beams, but MC was used to confirm that there are dose variations within the target volume. The MC results found that delivery of the treatment beam avoiding the stent was the best method to prevent target volume underdose. [ABSTRACT FROM AUTHOR]

Introduction: Aggressive cancers commonly ferment glucose to lactic acid at high rates, even in the presence of oxygen. This is known as aerobic glycolysis, or the "Warburg Effect." It is widely assumed that this is a consequence of the upregulation of glycolytic enzymes. Oncogenic drivers can increase the expression of most proteins in the glycolytic pathway, including the terminal step of exporting H+ equivalents from the cytoplasm. Proton exporters maintain an alkaline cytoplasmic pH, which can enhance all glycolytic enzyme activities, even in the absence of oncogene-related expression changes. Based on this observation, we hypothesized that increased uptake and fermentative metabolism of glucose could be driven by the expulsion of H+ equivalents from the cell. Results: To test this hypothesis, we stably transfected lowly glycolytic MCF-7, U2-OS, and glycolytic HEK293 cells to express proton-exporting systems: either PMA1 (plasma membrane ATPase 1, a yeast H+-ATPase) or CA-IX (carbonic anhydrase 9). The expression of either exporter in vitro enhanced aerobic glycolysis as measured by glucose consumption, lactate production, and extracellular acidification rate. This resulted in an increased intracellular pH, and metabolomic analyses indicated that this was associated with an increased flux of all glycolytic enzymes upstream of pyruvate kinase. These cells also demonstrated increased migratory and invasive phenotypes in vitro, and these were recapitulated in vivo by more aggressive behavior, whereby the acid-producing cells formed higher-grade tumors with higher rates of metastases. Neutralizing tumor acidity with oral buffers reduced the metastatic burden. Conclusions: Therefore, cancer cells which increase export of H+ equivalents subsequently increase intracellular alkalization, even without oncogenic driver mutations, and this is sufficient to alter cancer metabolism towards an upregulation of aerobic glycolysis, a Warburg phenotype. Overall, we have shown that the traditional understanding of cancer cells favoring glycolysis and the subsequent extracellular acidification is not always linear. Cells which can, independent of metabolism, acidify through proton exporter activity can sufficiently drive their metabolism towards glycolysis providing an important fitness advantage for survival. [ABSTRACT FROM AUTHOR]

Higher dose rates, a trend for radiotherapy machines, can be beneficial in shortening treatment times for radiosurgery and mitigating the effects of motion. Recently, even higher doses (e.g., 100 times greater) have become targeted because of their potential to generate the FLASH effect (FE). We refer to these physical dose rates as ultra‐high (UHDR). The complete relationship between UHDR and the FE is unknown. But UHDR systems are needed to explore the relationship further and to deliver clinical UHDR treatments, where indicated. Despite the challenging set of unknowns, the authors seek to make reasonable assumptions to probe how existing and developing technology can address the UHDR conditions needed to provide beam generation capable of producing the FE in preclinical and clinical applications. As a preface, this paper discusses the known and unknown relationships between UHDR and the FE. Based on these, different accelerator and ionizing radiation types are then discussed regarding the relevant UHDR needs. The details of UHDR beam production are discussed for existing and potential future systems such as linacs, cyclotrons, synchrotrons, synchrocyclotrons, and laser accelerators. In addition, various UHDR delivery mechanisms are discussed, along with required developments in beam diagnostics and dose control systems. [ABSTRACT FROM AUTHOR]

Measurements of particle fluxes (protons and electrons) obtained with the Influence sur les Composants Avancées des Radiations de l’Espace for New Generation (ICARE_NG) monitor on the Eutelsat 7C orbit [Electric Orbit Raising to Geostationary Orbit (GEO)] are presented. Several comparisons are proposed with other instruments [magnetic electron ion spectrometer (MagEIS), relativistic proton spectrometer (RPS), and magnetospheric particle sensors high (MPSH)] and radiation models (AEP8, International Radiation Environment Near Earth (IRENE), and Global Radiation Earth ENvironment (GREEN)). Significant discrepancies have been found, especially with AEP8 model. The measurements when the satellite is in its operational orbit (GEO) have also been compared with the International Geostationary Electron (IGE) model and an excellent agreement is observed. For calculating fluxes from ICARE_NG outputs, two methods have been developed and their results are compared to consolidate our interpretations. [ABSTRACT FROM AUTHOR]

Acidosis and its associated pathologies predispose patients to develop cardiac arrhythmias and even cardiac arrest. These arrhythmias are assumed to be the result of membrane depolarization, however, the exact mechanism of depolarization during acidosis is not well defined. In our study, the model of quantum tunneling of protons is used to explain the membrane depolarization that occurs during acidosis. It is found that protons can tunnel through closed activation and inactivation gates of voltage-gated sodium channels Nav1.5 that are present in the membrane of cardiac cells. The quantum tunneling of protons results in quantum conductance, which is evaluated to assess its effect on membrane potential. The quantum conductance of extracellular protons is higher than that of intracellular protons. This predicts an inward quantum current of protons through the closed sodium channels. Additionally, the values of quantum conductance are influential and can depolarize the membrane potential according to the quantum version of the GHK equation. The quantum mechanism of depolarization is distinct from other mechanisms because the quantum model suggests that protons can directly depolarize the membrane potential, and not only through indirect effects as proposed by other mechanisms in the literature. Understanding the pathophysiology of arrhythmias mediated by depolarization during acidosis is crucial to treat and control them and to improve the overall clinical outcomes of patients.

Multi-analyte detection and imaging of extracellular chemical signaling molecules are crucial for understanding brain function and molecular pathology. In this work, we present a 6-μm-pitch, CMOS-based multichemical image sensor that enables the simultaneous visualization and spatiotemporal multimodal analysis of the lactate and proton (H+) dynamics without any labeling. Using semiconductor lithography, gold electrode patterns functioning as lactate-sensing regions were formed on a potentiometric sensor array. Lactate is detected potentiometrically because of redox reactions using lactate oxidase and horseradish peroxidase. The resulting multichemical image sensor exhibited a pH sensitivity of 65 mV and a superior detection limit of 1 μM for lactate with a reasonable selectivity. Furthermore, diffusion images of lactate and H+ distributions were obtained concurrently, allowing for simultaneous real-time imaging of the two chemicals with subcellular resolution. We believe that our novel imaging device can be successfully applied to extracellular microenvironments in tissue or cell samples as an effective bioimaging tool. [ABSTRACT FROM AUTHOR]

This study explores the radiation shielding potential of Na 2 O–SiO 2 glass matrices doped with BaO, ZnO, CdO, and SrO, analysed across a broad energy spectrum. The research employed various computational tools such as Phy-X/PSD and PAGEX codes to calculate various shielding parameters, including Kinetic Energy Released in Material (KERMA), mass stopping power, fast neutron, and gamma-ray attenuation properties. Among the glass samples, S3, with its BaO content, exhibited the most advantageous properties in terms of radiation attenuation. The results showed that S3 has the lowest Half Value Layer (HVL) of 0.032 cm at 0.015 MeV and the highest KERMA value, peaking at 0.3 MeV with 0.18 MeV/g. The mass stopping power values for alpha particles in the S3 sample showed a pronounced peak at 0.7 MeV, reaching 150 MeV cm2/g, indicating superior energy absorption. The S3 sample, composed of 20% Na 2 O, 20% BaO, and 60% SiO 2 , demonstrated the highest density (i.e., 3.225 g/cm³) and effective atomic number (i.e., 17.5), which contributed to its superior shielding performance. The study's findings show that the careful manipulation of glass composition, particularly through the incorporation of high-atomic-number oxides, can significantly enhance shielding effectiveness. It can be concluded that the S3 glass sample would be an optimal configuration for practical applications in radiation protection, where the Na 2 O–SiO 2 glass matrices doped with BaO in terms of optimal material properties. • BaO-doped Na 2 O–SiO 2 glasses superior in gamma radiation shielding than ZnO, CdO, SrO. • S3 sample with 20% BaO exhibits best shielding, demonstrating high KERMA, mass stopping power. • Incorporating high-atomic-number oxides enhances glass shielding effectiveness significantly. • S3 glass composition is optimal shielding purposes. [ABSTRACT FROM AUTHOR]

A precise relative stopping power map of the patient is crucial for accurate particle therapy. Charged particle imaging determines the stopping power either tomographically - particle computed tomography (pCT) - or by combining prior knowledge from particle radiography (pRad) and x-ray CT. Generally, multiple Coulomb scattering limits the spatial resolution. Compared to protons, heavier particles scatter less due to their lower charge/mass ratio. A theoretical framework to predict the most likely trajectory of particles in matter was developed for light ions up to carbon and was found to be the most accurate for helium comparing for fixed initial velocity. To further investigate the potential of helium in particle imaging, helium computed tomography (HeCT) and radiography (HeRad) were studied at the Heidelberg Ion-Beam Therapy Centre (HIT) using a prototype pCT detector system registering individual particles, originally developed by the U.S. pCT collaboration. Several phantoms were investigated: modules of the Catphan QA phantom for analysis of spatial resolution and achievable stopping power accuracy, a paediatric head phantom (CIRS) and a custommade phantom comprised of animal meat enclosed in a 2 % agarose mixture representing human tissue. The pCT images were reconstructed applying the CARP iterative reconstruction algorithm. The MTF10% was investigated using a sharp edge gradient technique. HeRad provides a spatial resolution above that of protons (MTF1010%=6.07 lp/cm for HeRad versus MTF10%=3.35 lp/cm for proton radiography). For HeCT, the spatial resolution was limited by the number of projections acquired (90 projections for a full scan). The RSP accuracy for all inserts of the Catphan CTP404 module was found to be 2.5% or better and is subject to further optimisation. In conclusion, helium imaging appears to offer higher spatial resolution compared to proton imaging. In future studies, the advantage of helium imaging compared to other imaging modalities in clinical applications will be further explored.