ABSTRACT
BACKGROUND: Glioblastoma multiforme (GBM) is an aggressive type of brain tumor that is difficult to remove surgically. Research suggests that substances from saffron, namely crocetin and crocin, could be effective natural treatments, showing abilities to kill cancer cells. METHODS: Our study focused on evaluating the effects of crocetin on glioma using the U87 cell line. We specifically investigated how crocetin affects the survival, growth, and spread of glioma cells, exploring its impact at concentrations ranging from 75-150 µM. The study also included experiments combining crocetin with the chemotherapy drug Temozolomide (TMZ) to assess potential synergistic effects. RESULTS: Crocetin significantly reduced the viability, proliferation, and migration of glioma cells. It achieved these effects by decreasing the levels of Matrix Metallopeptidase 9 (MMP-9) and Ras homolog family member A (RhoA), proteins that are critical for cancer progression. Additionally, crocetin inhibited the formation of cellular structures necessary for tumor growth. It blocked multiple points of the Ak Strain Transforming (AKT) signaling pathway, which is vital for cancer cell survival. This treatment led to increased cell death and disrupted the cell cycle in the glioma cells. When used in combination with TMZ, crocetin not only enhanced the reduction of cancer cell growth but also promoted cell death and reduced cell replication. This combination therapy further decreased levels of high mobility group box 1 (HMGB1) and Receptor for Advanced Glycation End-products (RAGE), proteins linked to inflammation and tumor progression. It selectively inhibited certain pathways involved in the cellular stress response without affecting others. CONCLUSION: Our results underscore the potential of crocetin as a treatment for glioma. It targets various mechanisms involved in tumor growth and spread, offering multiple avenues for therapy. Further studies are essential to fully understand and utilize crocetin's benefits in treating glioma.
ABSTRACT
This study assessed the biocompatibility of two types of nanogold composites: fibronectin-gold (FN-Au) and collagen-gold (Col-Au). It consisted of three main parts: surface characterization, in vitro biocompatibility assessments, and animal models. To determine the structural and functional differences between the materials used in this study, atomic force microscopy, Fourier-transform infrared spectroscopy, and ultraviolet-visible spectrophotometry were used to investigate their surface topography and functional groups. The F-actin staining, proliferation, migration, reactive oxygen species generation, platelet activation, and monocyte activation of mesenchymal stem cells (MSCs) cultured on the FN-Au and Col-Au nanocomposites were investigated to determine their biological and cellular behaviors. Additionally, animal biocompatibility experiments measured capsule formation and collagen deposition in female Sprague-Dawley rats. The results showed that MSCs responded better on the FN-Au and Col-AU nanocomposites than on the control (tissue culture polystyrene) or pure substances, attributed to their incorporation of an optimal Au concentration (12.2 ppm), which induced significant surface morphological changes, nano topography cues, and better biocompatibility. Moreover, neuronal, endothelial, bone, and adipose tissues demonstrated better differentiation ability on the FN-Au and Col-Au nanocomposites. Nanocomposites have a crucial role in tissue engineering and even vascular grafts. Finally, MSCs were demonstrated to effectively enhance the stability of the endothelial structure, indicating that they can be applied as promising alternatives to clinics in the future.
Subject(s)
Biocompatible Materials , Cell Differentiation , Gold , Mesenchymal Stem Cells , Nanocomposites , Rats, Sprague-Dawley , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Gold/chemistry , Animals , Nanocomposites/chemistry , Cell Differentiation/drug effects , Rats , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Female , Cell Proliferation/drug effects , Collagen/chemistry , Biopolymers/chemistry , Fibronectins/metabolism , Cells, Cultured , Metal Nanoparticles/chemistry , Materials Testing , Tissue Engineering/methods , Reactive Oxygen Species/metabolism , Cell Movement/drug effectsABSTRACT
This study utilized Next-Generation Sequencing (NGS) to explore genetic determinants of survival duration in Glioblastoma Multiforme (GBM) patients. We categorized 30 primary GBM patients into two groups based on their survival periods: extended survival (over two years, N = 17) and abbreviated survival (under two years, N = 13). For identifying pathogenic or likely pathogenic variants, we leveraged the ClinVar database. The cohort, aged 23 to 66 (median: 53), included 17 patients in Group A (survival >2 years, 10 males, 7 females), and 13 patients in Group B (survival <2 years, 8 males, 5 females), with a 60% to 40% male-to-female ratio. Identified mutations included CHEK2 (c.1477 G > A, p.E493K), IDH1 (c.395 G > A, p.R132H), and TP53 mutations. Non-coding regions exhibited variants in the TERT promoter (c.-146C > T, c.-124C > T) and TP53 RNA splicing site (c.376-2 A > C, c.376-2 A > G). While Group A had more mutations, statistical significance wasn't reached, likely due to sample size. Notably, TP53, and ATR displayed a trend toward significance. Surprisingly, TP53 mutations were more prevalent in Group A, contradicting Western findings on poorer GBM prognosis. In Taiwanese GBM patients, bevacizumab usage is linked to improved survival rates, affirming its safety and effectiveness. EGFR mutations are infrequent, suggesting potential distinctions in carcinogenic pathways. Further research on EGFR mutations and amplifications is essential for refining therapeutic approaches. TP53 mutations are associated with enhanced survival, but their functional implications necessitate detailed exploration. This study pioneers genetic analysis in Taiwanese GBM patients using NGS, advancing our understanding of their genetic landscape.
Subject(s)
Glioblastoma , Mutation , Humans , Glioblastoma/genetics , Glioblastoma/mortality , Male , Female , Middle Aged , Adult , Taiwan/epidemiology , Aged , Retrospective Studies , Young Adult , Brain Neoplasms/genetics , Brain Neoplasms/mortality , High-Throughput Nucleotide Sequencing , PrognosisABSTRACT
In this study, we developed a cost-effective fluorescence visual sensor strategy based on gold and silver nanocluster (Au-AgNCs) for the rapid identification of the origins and growth years of Lilium bulbs (LB). Au-AgNCs combined with catechins in LB produce aggregation-induced emission (AIE). The catechin content in LB of different origins and growth years varied, resulting in different fluorescence color responses of the sensor system. Furthermore, the RGB values of the fluorescent color were extracted, and the discriminant effect of visual visualisation was verified using the data-driven soft independent modelling of class analogy (DD-SIMCA) and partial least squares discriminant analysis (PLSDA) models. The results showed that the accuracy of DD-SIMCA for identifying LB origins and PLSDA for growth year identification was 100%. These results indicated that the established strategy could accurately identify the quality of LB, which has great potential for application in the rapid and visual identification of other foods.
Subject(s)
Lilium , Metal Nanoparticles , Fluorescence , Silver , Coloring Agents , GoldABSTRACT
OBJECTIVE: Studies utilizing the discrepancy model of the Mayo-Portland Adaptability Inventory-4 (MPAI-4) have commonly used the cognitive and physical domains to estimate self-awareness. This study included other aspects of self-awareness such as awareness of one's social and emotional status and daily functioning to explore their effects on caregiver burden for ABI survivors. METHODS: We studied 64 patient-caregiver pairs up to 29 years post-discharge from a holistic, milieu-oriented outpatient neurorehabilitation program. Discrepancy scores between ABI survivors' and caregivers' reports on the MPAI-4 subscales (i.e. Abilities, Adjustment, and Participation) and Total Score were used to determine self-awareness. Caregiver burden was measured using the Zarit Burden Interview (ZBI). RESULTS: Exploratory linear regression analyses revealed that caregiver burden derived from the ZBI was predicted by the discrepancy scores generated from the Abilities (p < 0.0001), Adjustment (p < 0.01), Participation subscales (p = 0.01), and Total Score (p < 0.001), respectively. Among the exploratory models generated, the Total Score model had the highest predictive value (R2 = .33) for caregiver burden. CONCLUSIONS: Measures of self-awareness should be comprehensive by considering diverse components of self-awareness. Increasing ABI survivors' self-awareness in different domains has the potential to effectively alleviate caregiver burden.
Subject(s)
Aftercare , Caregiver Burden , Humans , Follow-Up Studies , Patient Discharge , Caregivers/psychology , Cost of IllnessABSTRACT
Messenger RNA (mRNA) vaccines emerge as promising vaccines to prevent infectious diseases. Compared with traditional vaccines, mRNA vaccines present numerous advantages, such as high potency, safe administration, rapid production potentials, and cost-effective manufacturing. In 2020, two COVID-19 vaccines (BNT162b2 and mRNA-1273) were approved by the Food and Drug Administration (FDA). The two vaccines showed high efficiency in combating COVID-19, which indicates the great advantages of mRNA technology in developing vaccines against emergent infectious diseases. Here, we summarize the type, immune mechanisms, modification methods of mRNA vaccines, and their applications in preventing infectious diseases. Current challenges and future perspectives in developing mRNA vaccines are also discussed.
Subject(s)
Communicable Diseases , mRNA Vaccines , United States , Humans , BNT162 Vaccine , COVID-19 Vaccines/genetics , RNA, Messenger/geneticsABSTRACT
The excessive presence of phosphate can cause eutrophication in water bodies. Yttrium has an extremely high affinity for phosphorus and is capable of forming stable complexes at low concentrations. Moreover, limitations in the resourcefulness of drinking water treatment residues were observed. In this study, a highly efficient phosphorus removal adsorbent (RJDWTR@Y) was prepared by calcination-alkali leaching-yttrium-loaded composite modification employing domestic drinking water treatment residue as raw material. And the effects of multiple factors on phosphate adsorption by RJDWTR@Y were examined. The results illustrated that the maximum adsorption capacity of the RJDWTR@Y for phosphate was 319.76 mg/g, with the chemical reaction of the multilayer as the predominant adsorption process. The adsorption mechanism is electrostatic gravitational force and the inner sphere complexation effect. RJDWTR@Y was effective against interference even at high concentrations of the coexisting anion. After five cycles, the desorption efficiency of phosphate was 75.11%. Filling the fixed bed with the material can efficiently remove phosphorus from the flowing liquid. The synthesis of RJDWTR@Y and the results of the study indicated that it has good application prospects. In addition to efficiently removing phosphorus, it can also recycle waste and achieve sustainability.
Subject(s)
Drinking Water , Water Pollutants, Chemical , Phosphorus/chemistry , Yttrium , Reproducibility of Results , Wastewater , Kinetics , Phosphates/chemistry , Adsorption , Water Pollutants, Chemical/chemistry , Hydrogen-Ion ConcentrationABSTRACT
Glioblastoma (GBM), a prevalent and malignant brain tumor, poses a challenge in surgical resection due to its invasive nature within the brain parenchyma. CDKN1A (p21, Waf-1), a cyclin-dependent kinase inhibitor, plays a pivotal role in regulating cell growth arrest, terminal differentiation, and apoptosis. The existence of natural variants of CDKN1A has been associated with specific cancer types. In this retrospective study, our objective was to identify polymorphic variants of CDKN1A, specifically c.93C > A (codon 31 Ser31Arg), and investigate its potential impact within the scope of bevacizumab therapy for glioblastoma multiforme. This study involved a cohort of 139 unrelated adult Chinese GBM patients in Taiwan. Genomic DNA extracted from tumor samples was utilized for genotyping using the polymerase chain reaction (PCR) restriction fragment length polymorphism method (PCR-RFLP analysis). Through unconditional logistic regression analysis, odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Our findings unveiled that among these GBM patients, the distribution of codon 31 polymorphisms was as follows: 23.02% were Serine homozygotes (Ser/Ser), 27.34% were Arginine homozygotes (Arg/Arg), and 49.64% were Serine/Arginine heterozygotes (Ser/Arg). While CDKN1A c.93C > A polymorphisms did not exhibit a direct association with overall survival in GBM patients, noteworthy survival benefits emerged among individuals with Arg/Arg and Arg/Ser genotypes who received combined concurrent chemoradiotherapy (CCRT) and bevacizumab treatment compared to those who underwent CCRT alone. Our findings indicate a significant involvement of the CDKN1A c.93C > A polymorphism in the development and onset of GBM, offering potential implications for the early prognostication of bevacizumab therapy outcomes.
Subject(s)
Glioblastoma , Adult , Humans , Glioblastoma/drug therapy , Glioblastoma/genetics , Bevacizumab/therapeutic use , Retrospective Studies , Arginine , Codon , Cyclin-Dependent Kinase Inhibitor p21/geneticsABSTRACT
BACKGROUND: Intraventricular hemorrhage (IVH) is a type of ventricular bleeding that results in significant morbidity and mortality. Multiple studies have investigated the use of urokinase in IVH treatment. The use of urokinase may lead to higher rates of hematoma resolution and lower mortality rates. However, further studies are required to determine efficacy of urokinase administration. This study examined the association between urokinase use, IVH volume reduction, and clinical outcomes. METHODS: In total, 94 adult patients with hypertensive intracerebral hemorrhage with ventricular extension or primary IVH were enrolled between 2015 and 2021. Participants were categorized into two groups: "EVD combined with fibrinolysis" and "EVD only." The primary objective was to assess the reduction of IVH severity. Additionally, the study evaluated the functional outcomes and shunt dependency rate as secondary outcomes. Non-contrast computed tomography scans were obtained to measure the severity of IVH using the mGRAEB score. The main outcomes were the association among urokinase administration, reduced IVH severity, and functional outcomes. RESULTS: There were no significant differences in the reduction rate of mGRAEB scores within a 7-day period (-50.0 [-64.4 to -32.5] % vs -44.2 [-59.3 to -7.9] %; p = 0.489). In addition, investigation of the third and fourth ventricles showed similar findings between the two groups. Urokinase treatment was not associated with significant differences in the modified Rankin Scale (5.0 (4.0-5.0) vs. 4.5 (4.0-5.0), p = 0.674) or shunt dependency rate (33.3% vs 39.3%, p = 0.58). CONCLUSION: This study found that intraventricular urokinase use in patients with IVH was not associated with reduced IVH severity. In addition, urokinase use was not associated with better functional outcomes or minor shunt dependency rates.
Subject(s)
Cerebral Hemorrhage , Urokinase-Type Plasminogen Activator , Adult , Humans , Cerebral Hemorrhage/drug therapy , Cerebral Ventricles , Retrospective Studies , Treatment Outcome , Urokinase-Type Plasminogen Activator/therapeutic useABSTRACT
BACKGROUND: Dendritic Cell Cytokine-induced killer cell (DC-CIK) coculture treatment in cancer immunotherapy has been shown to be effective. However, the cost of DC- CIK therapy is prohibitive for many patients, and the lack of standard manufacturing processes and treatment strategies are major limitations. Our study used tumor lysate as a tumor-associated antigen source and DCs and CIK cells in coculture. We developed an efficient method to obtain autologous DCs- and CIK cells from peripheral blood. We used flow cytometry to assess DC activation and the cytometric bead array assay to quantify cytokines secreted by CIK cells. RESULTS: We evaluated the antitumor activity of DC- CIK coculture in vitro with the K562 cell line. We demonstrated that a manufacturing process employing frozen immature DCs can yield the lowest loss with the highest economic benefits. DC-CIK coculture can effectively upgrade CIK cells' immunological specificity to tumors in the presence of tumor-associated antigens. CONCLUSION: In vitro experiments revealed that when the DC- CIK cell ratio was 1: 20 in the coculture, CIK cells secreted the highest number of cytokines on the 14th day and the antitumor immune effect showed the highest potency. CIK cells' cytotoxicity to K562 cells was highest when the CIK: K562 cell ratio was 25: 1. We developed an efficient manufacturing process for DC- CIK coculture, while also establishing the optimal DC- CIK cell ratio for immunological activity and the best cytotoxic CIK: K562 cell ratio.
Subject(s)
Cytokine-Induced Killer Cells , Neoplasms , Humans , Coculture Techniques , Immunotherapy , Cytokines , Dendritic CellsABSTRACT
Rational treatment of drinking water treatment residues (WTR) has become an environmental and social issue due to the risk of secondary contamination. WTR has been commonly used to prepare adsorbents because of its clay-like pore structure, but then requires further treatment. In this study, a Fenton-like system of H-WTR/HA/H2O2 was constructed to degrade organic pollutants in water. Specifically, WTR was modified by heat treatment to increase its adsorption active site, and to accelerate Fe(III)/Fe(II) cycling on the catalyst surface by the addition of hydroxylamine (HA). Moreover, the effects of pH, HA and H2O2 dosage on the degradation were discussed with methylene blue (MB) as the target pollutant. The mechanism of the action of HA was analyzed and the reactive oxygen species in the reaction system were determined. Combined with the reusability and stability experiments, the removal efficiency of MB remained 65.36% after 5 cycles. Consequently, this study may provide new insights into the resource utilization of WTR.
Subject(s)
Drinking Water , Water Pollutants, Chemical , Hydroxylamine/chemistry , Hydrogen Peroxide/chemistry , Iron/chemistry , Methylene Blue , Hot Temperature , Water Pollutants, Chemical/analysis , Hydroxylamines , Oxidation-ReductionABSTRACT
In the present study, the various concentrations of AuNP (1.25, 2.5, 5, 10 ppm) were prepared to investigate the biocompatibility, biological performances and cell uptake efficiency via Wharton's jelly mesenchymal stem cells and rat model. The pure AuNP, AuNP combined with Col (AuNP-Col) and FITC conjugated AuNP-Col (AuNP-Col-FITC) were characterized by Ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR) and Dynamic Light Scattering (DLS) assays. For in vitro examinations, we explored whether the Wharton's jelly MSCs had better viability, higher CXCR4 expression, greater migration distance and lower apoptotic-related proteins expression with AuNP 1.25 and 2.5 ppm treatments. Furthermore, we considered whether the treatments of 1.25 and 2.5 ppm AuNP could induce the CXCR4 knocked down Wharton's jelly MSCs to express CXCR4 and reduce the expression level of apoptotic proteins. We also treated the Wharton's jelly MSCs with AuNP-Col to investigate the intracellular uptake mechanisms. The evidence demonstrated the cells uptake AuNP-Col through clathrin-mediated endocytosis and the vacuolar-type H+-ATPase pathway with good stability inside the cells to avoid lysosomal degradation as well as better uptake efficiency. Additionally, the results from in vivo examinations elucidated the 2.5 ppm of AuNP attenuated foreign body responses and had better retention efficacy with tissue integrity in animal model. In conclusion, the evidence demonstrates that AuNP shows promise as a biosafe nanodrug delivery system for development of regenerative medicine coupled with Wharton's jelly MSCs.
ABSTRACT
When a different types of reactor are operating at the same area and the same period of time, released radionuclides are hard to follow in the environment. In general, isotopic techniques can be used for source localization. To obtain the distribution of hydrogen isotope in soil, eight sampling points were selected along the local dominant wind direction with different distances away from Qinshan Nuclear Power Plant, and soil samples at different depths (0-2, 2-5, 5-10, 10-20, 20-30 cm) were collected in December 2019 and December 2020, respectively. The concentrations of hydrogen isotopes were measured in the soil samples at different depth. The spatial distribution of tritium and deuterium in the surface soil was related to soil properties and the distance from the nuclear power plant. It was found that tritium and deuterium are generally enriched in the upper layer. Determination of the deuterium concentration in the environment may be a new way to trace the released tritium from the reactors.
Subject(s)
Radiation Monitoring , Soil , Nuclear Power Plants , Hydrogen , Tritium/analysis , Deuterium , Radiation Monitoring/methodsABSTRACT
The coexistence of glioblastoma multiforme (GBM) and arteriovenous malformation (AVM) is rarely reported in the literature. According to the present literature, these GBM or glioma-related vascular malformations may present simultaneously in distinct regions of the brain or occur in the same area but at different times. So far, these distinct hypervascular glioblastomas have been described but are not classified as a separate pathological entities. Considering their heterogeneity and complexity, all the above mentioned cases remain challenging in diagnosis and therapeutic modality. Likewise, there is a paucity of data surrounding the simultaneous presentation of GBM with intracranial aneurysms. In the literature, the independent concurrence of these three intracranial lesions has never been reported. In this article, we present a case who suffered from intermittent headaches and dizziness initially and further radiographic examination revealed an internal carotid artery (ICA) aneurysm that occurred in the patient with coexisting GBM and AVM. Surgical intervention for tumor and AVM removal was performed smoothly. This patient underwent endovascular coiling for the ICA aneurysm 4 months postoperatively. In addition, we also review the current literature relating to this rare combination of medical conditions.
Subject(s)
Glioblastoma , Intracranial Aneurysm , Intracranial Arteriovenous Malformations , Humans , Intracranial Arteriovenous Malformations/complications , Intracranial Arteriovenous Malformations/diagnosis , Intracranial Arteriovenous Malformations/surgery , Triploidy , BrainABSTRACT
BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) is a rare but potentially devastating cause of severe spinal cord compression and degenerative cervical myelopathy. Because OPLL is rarely accompanied by prominent syringomyelia, when both are observed, other causes of syringomyelia should be considered. Simultaneous presentation of OPLL and hemangioblastoma of the cervical spine is a rare encounter and has never been reported in the English-language literature. OBSERVATIONS: The authors present a case of a 64-year-old man with muscle weakness of the right upper limb and worsening dysesthesia of the right thumb and index finger. Noncontrast magnetic resonance imaging (MRI) of the cervical spine from another institution revealed OPLL from the C2 to C6 levels with severe spinal cord compression and prominent syringomyelia. Repeated MRI with contrast showed an intramedullary tumor, about 11 mm in diameter, at the right posterior aspect of the C4 level. The authors performed laminectomies from C1 to C6 with posterolateral fusion and removed the C4 tumor. Pathohistological examination of the tumor demonstrated hemangioblastoma. LESSONS: Careful evaluation of the preoperative imaging study is extremely important in surgical decision making. Although rare, concomitant cervical hemangioblastoma should be listed in the differential diagnosis when OPLL is accompanied with prominent syringomyelia.
ABSTRACT
Excessive fluoride ions (F-) in drinking water are harmful to the environment and human health. However, most reported probes of F- can only detect fluorocarbons rather than aqueous F-. Herein, a colorimetric and fluorescent probe (PMI-OH) based on perylenemonoimide is designed and synthesized for the detection of aqueous F-, with high sensitivity, good selectivity, and reversibility. The F- causes deprotonation of PMI-OH, leading to a significant red shift of 222 nm (from 520 to 742 nm) of the absorption band. Upon the addition of fluorocarbons, the fluorescence intensities of PMI-OH show good linearity against the concentrations of F-, realizing the quantitative detection of fluorocarbons with a limit of detection as low as 0.495 µM. Finally, PMI-OH is applied to detect F- in drinking water. The color of PMI-OH solution shows remarkable response from pink to green when the concentrations of F- exceed the upper limit set by the World Health Organization (WHO), realizing rapid and naked-eye detection of aqueous F-.
Subject(s)
Drinking Water , Fluorocarbons , Colorimetry , Fluorescent Dyes , Fluorides , Fluorine , Humans , Imides , Ions , Perylene/analogs & derivativesABSTRACT
BACKGROUND: Flow diverter stenting is an effective treatment for large proximal internal carotid artery (ICA) aneurysms. Cranial neuropathy caused by the mass effect of the aneurysm usually subsides over time. However, a new onset of compressive optic neuropathy after successful flow diverter stenting of a large proximal ICA aneurysm is seldom reported. OBSERVATIONS: A 57-year-old woman had a right supraclinoid ICA aneurysm (approximately 17 mm) on magnetic resonance angiography (MRA) in a health checkup. She received intervention with the Pipeline embolization device. Six months later, she started to experience progressive hemianopia in the left half of the visual field. Nine months after stenting, MRA showed that the aneurysm was growing and causing mass effect, but digital subtraction angiography confirmed that the aneurysm was completely excluded from the circulation. She received a craniotomy for microsurgical decompression of the optic nerve and coagulation shrinkage of the aneurysm. Clipping and thrombectomy were not attempted. Her visual fields recovered gradually. Follow-up MRA showed that the aneurysm also diminished in size. LESSONS: Whether the coagulation technique of the flow-diverter-occluded aneurysm alone is enough to cause satisfactory shrinkage and interaction between the flow diverter and the aneurysmal vasa vasorum/neointima formation should be further examined.
ABSTRACT
Tritium deposited in soil forms HTO and OBT. To further understand the changes of HTO and OBT in different years, HTO and OBT in the soil around Qinshan Nuclear Power Base in different sampling years were measured. According to the annual distribution of HTO and OBT in the surface soil, it could be inferred whether there was a long-term release of tritium in the observed year. From the depth distribution of different years, OBT tends to migrate to the deep. From 2015 to 2020, the correlation analysis between OBT and HTO/soil organic matter showed that HTO contributed more to OBT in surface soil at 250-2000 µm and 53-250 µm particle sizes, but this conclusion did not apply to deep soil. However, there was no significant relationship between OBT activity and soil organic matter content.
Subject(s)
Nuclear Power Plants , Radiation Monitoring , Particle Size , Soil , Tritium/analysisABSTRACT
Single-layer graphene has been demonstrated to be a high-efficiency hydrogen isotope sieving membrane in the electrochemical hydrogen pumping system. In this work, we transferred this membrane to proton exchange membrane water electrolysis (PEMWE), which has wide industrial applications. Two membrane electrode assemblies with decorated Pt and ink-coated Pt were investigated. The graphene with the decorated Pt scheme acquired the reported highest proton-to-tritium separation factor of 19.50 in PEMWE. However, rather than graphene, the decorated catalyst was demonstrated to be responsible for this remarkable separation efficiency. Previous studies from Geim's group underestimated the enhanced separation efficiency of decorated Pt over ink-coated Pt, resulting in an exaggerated separation efficiency for graphene. The behavior of proton transfer with hydrogen isotope separation through graphene was interpreted by a serial-parallel circuit model, which suggested that hydrogen isotope separation occurs at defect sites. The limited separation efficiency for graphene was also well understood by a density functional theory (DFT) calculation using an SW 55-77 model and the transition state theory for the kinetic isotope effect. This research provides a thorough understanding of proton transfer with hydrogen isotope separation through graphene.