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In this work, the performance, electrochemical processes, and stability of GDC (Ce0.8Gd0.2O1.9) fuel electrode containing single cells (GDC/8YSZ/GDC/LSCF) were examined in CO2 electrolysis conditions. The current density and area specific resistance is determined for different operation conditions. The examined cells showed a higher performance compared to state‐of‐the‐art Ni−YSZ fuel electrode (Ni‐YSZ/8YSZ/GDC/LSCF) based single cells with a similar production route. Furthermore, the cells were examined by means of electrochemical impedance spectroscopy (EIS) and the recorded data were evaluated by the distribution of relaxation times (DRT) analysis. An equivalent circuit model (ECM) consisting of four time constants and a Gerischer impedance (LR−RQ1−RQ2−G−RQ4−RQ5) was established to gain further insight into the individual processes in the cells. For instance, the low–frequency process P5 referring to RQ5 is the rate‐determining step in CO2 electrolysis and is assigned to a surface reaction including the charge transfer and possibly the gas diffusion in the GDC fuel electrode. A long–term stability test was performed in CO2 electrolysis conditions at 900 °C with a constant current load of −0.5 A ⋅ cm−2 for up to 1200 h. A degradation rate of 62 mV ⋅ kh−1 was observed. By EIS analysis, a similar contribution of the ohmic and polarization resistances to the degradation was determined. The low–frequency process P5 and thus the surface reaction including the charge transfer in the GDC fuel electrode is contributing most to the increase in polarization resistance. After the long–term stability test, scanning electron microscopy (SEM) analysis was carried out and a coarsening of GDC particles in the fuel electrode was observed. [ABSTRACT FROM AUTHOR]

In our previous work, the effect of Gd alloying on the oxidation resistance of AZ80 alloy was revealed briefly. However, a comprehensive understanding of the oxidation and corrosion resistance of the oxide layer formed on the Gd alloying AZ80 alloy surface needs to be developed. Thus, in this research, the high-temperature oxidation behaviors, oxidation products, and oxide layer characteristics of AZ80, AZ80-0.47Gd, and AZ80-0.75Gd (wt%) alloys were investigated at 420 °C. The corrosion protection of the oxide layer formed on the alloy surface was evaluated. The results showed that Gd alloying eliminated the content of the low melting point phase of β-Mg17Al12 and promoted the generation of a high melting point phase of Al2Gd. Gd2O3 appeared in the oxide layer and facilitated the propagation of homogeneous oxidation as well as densification of the oxide layer. In addition, the firm oxide layer showed characteristics of a blurred boundary with the magnesium matrix. After immersion of the oxide layer containing gadolinium oxide, the products of corrosion were massively nodulated, leading to the passivation of corrosion. This research provides new ideas for magnesium alloy protective layer preparation via a high-temperature oxidation technique. [ABSTRACT FROM AUTHOR]

The acquisition of images minutes or even hours after intravenous extracellular gadolinium-based contrast agents (GBCA) administration ("Late/Delayed Gadolinium Enhancement" imaging; in this review, further termed LGE) has gained significant prominence in recent years in magnetic resonance imaging. The major limitation of LGE is the long examination time; thus, it becomes necessary to understand when it is worth waiting time after the intravenous injection of GBCA and which additional information comes from LGE. LGE can potentially be applied to various anatomical sites, such as heart, arterial vessels, lung, brain, abdomen, breast, and the musculoskeletal system, with different pathophysiological mechanisms. One of the most popular clinical applications of LGE regards the assessment of myocardial tissue thanks to its ability to highlight areas of acute myocardial damage and fibrotic tissues. Other frequently applied clinical contexts involve the study of the urinary tract with magnetic resonance urography and identifying pathological abdominal processes characterized by high fibrous stroma, such as biliary tract tumors, autoimmune pancreatitis, or intestinal fibrosis in Crohn's disease. One of the current areas of heightened research interest revolves around the possibility of non-invasively studying the dynamics of neurofluids in the brain (the glymphatic system), the disruption of which could underlie many neurological disorders. [ABSTRACT FROM AUTHOR]

Objective: MR fingerprinting (MRF) can enable preclinical studies of cell tracking by quantifying multiple contrast agents simultaneously, but faster scan times are required for in vivo applications. Sliding window (SW)-MRF is one option for accelerating MRF, but standard implementations are not sufficient to preserve the accuracy of T2*, which is critical for tracking iron-labelled cells in vivo. Purpose: To develop a SW approach to MRF which preserves the T2* accuracy required for accelerated concentration mapping of iron-labelled cells on single-channel preclinical systems. Methods: A nonuniform SW was applied to the MRF sequence and dictionary. Segments of the sequence most sensitive to T2* were subject to a shorter window length, preserving the T2* sensitivity. Phantoms containing iron-labelled CD8+ T cells and gadolinium were used to compare 24× undersampled uniform and nonuniform SW-MRF parameter maps. Dual concentration maps were generated for both uniform and nonuniform MRF and compared. Results: Lin's concordance correlation coefficient, compared to gold standard parameter values, was much greater for nonuniform SW-MRF than for uniform SW-MRF. A Wilcoxon signed-rank test showed no significant difference between nonuniform SW-MRF and gold standards. Nonuniform SW-MRF outperformed the uniform SW-MRF concentration maps for all parameters, providing a balance between T2* sensitivity of short window lengths, and SNR of longer window lengths. Conclusions: Nonuniform SW-MRF improves the accuracy of matching compared to uniform SW-MRF, allowing higher accelerated concentration mapping for preclinical systems. [ABSTRACT FROM AUTHOR]

Improving the delivery of biomolecules to DCs and lymph nodes is critical to increasing their anti-tumor efficacy, reducing their off-target side effects, and improving their safety. In this study, Gd2O3 nanotubes with lengths of 70–80 nm, diameters of 20–30 nm, and pore sizes of up to 18 nm were synthesized using a facile one-pot solvothermal method. The Gd2O3 nanotubes showed good adsorption capacity of OVA and TLR7a, with a loading efficiency of about 100%. The Gd2O3 nanotubes showed pH-sensitive degradation and biomolecule release properties; the release of gadolinium ions, OVA, and TLR7a was slow at pH 7.4 and fast at pH 5. The Gd2O3 nanotubes showed 2.6–6.0 times higher payload retention around the injection site, 3.1 times higher cellular uptake, 1.7 times higher IL1β secretion, 1.4 times higher TNFα secretion by BMDCs, and markedly enhanced draining lymph node delivery properties. The combination of OVA, TLR7a, and Gd2O3 nanotubes significantly inhibited tumor growth and increased survival rate compared with only OVA-TLR7a, only OVA, and saline. The Gd2O3 nanotubes are biocompatible and can also be used as radiation sensitizers. [ABSTRACT FROM AUTHOR]

Free-running 5D whole-heart coronary MR angiography (MRA) is gaining in popularity because it reduces scanning complexity by removing the need for specific slice orientations, respiratory gating, or cardiac triggering. At 3T, a gradient echo (GRE) sequence is preferred in combination with contrast injection. However, neither the injection scheme of the gadolinium (Gd) contrast medium, the choice of the RF excitation angle, nor the dedicated image reconstruction parameters have been established for 3T GRE free-running 5D whole-heart coronary MRA. In this study, a Gd injection scheme, RF excitation angles of lipid-insensitive binominal off-resonance RF excitation (LIBRE) pulse for valid fat suppression and continuous data acquisition, and compressed-sensing reconstruction regularization parameters were optimized for contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence at 3T. Using this optimized protocol, contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence is feasible with good image quality at 3T. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to elucidate whether gadolinium contrast in clinically relevant doses can be used with photon‐counting computed tomography (PCCT) as an alternative contrast agent in clinical applications. Material/methods: A CTDI phantom with 3D printed rods filled with different concentrations of gadolinium and iodine contrast was scanned in a PCCT and an energy‐integrated computed tomography (EICT). Attenuation values at different monoenergetic steps were extracted for each contrast concentration. Results: For PCCT, gadolinium reached an attenuation >100 HU (103 HU) at 40 keV with a concentration 5 mmol/L whereas the same level was reached at 50 keV (118 HU) for 10 mmol/L and 90 keV (114 HU) for 25 mmol/L. For iodine, the same level of attenuation was reached at 100 keV (106 HU) with a concentration 8.75 mg I/mL. For EICT the lowest gadolinium contrast concentration needed to reach >100 HU (108 HU) was 10 mmol/L at 50 keV. For 25 mmol/L 100 HU was reached at 100 keV. For iodine contrast 108 HU was reached at 110 keV for 8.75 mg I/mL. Conclusion: No K‐edge potential or difference in attenuation curves between iodine and gadolinium contrast is detected on the first clinical available PCCT. Clinically relevant attenuation levels were barely achieved in this setting with gadolinium concentrations approved for human use. The results of this study suggest that, given current scanning technology, gadolinium is not a clinically useful contrast agent for computed tomography because no K‐edge was detected. [ABSTRACT FROM AUTHOR]

Introduction: Sites associated with gadolinium (Gd) deposition in the brain (e.g., the globus pallidus) are known to contain high concentrations of ferric iron. There is considerable debate over the mechanism of Gd deposition in the brain. The role of iron transport mechanisms in Gd deposition has not been determined. Thus, we seek to identify if Gd deposition can be controlled by modifying iron exposure.Methods: Female Sprague-Dawley rats were given diets with controlled iron levels at 2–6 ppm, 6 ppt (20 g/kg Fe carbonyl) or 48 ppm for 3 weeks to induce iron deficiency, overload or normalcy. They were kept on those diets while receiving a cumulative 10 mmol/kg dose of gadodiamide intravenously over 2 weeks, then left to washout gadodiamide for 3 days or 3 weeks before tissues were harvested. Gd concentrations in tissues were analyzed by ICP-MS.Results: There were no significant effect of dietary iron and total Gd concentrations in the organs, but there was a significant effect of iron status on Gd distribution in the brain. For the 3-week washout cohort, there was a non-significant trend of increasing total brain deposition and decreasing dietary iron, and about 4-fold more Gd in the olfactory bulbs of the low iron group compared to the other groups. Significant brain accumulation was observed in the low iron group total brain Gd in the 3-week washout group relative to the 3-day washout group and no accumulation was observed in other tissues. There was a strong negative correlation between femur Gd concentrations and concentrations in other organs when stratifying by dietary iron.Discussion: Gd brain deposition from linear Gd-based contrast agents (GBCAs) are dependent upon iron status, likely through variable transferrin saturation. This iron dependence appears to be associated with redistribution of peripheral deposited Gd (e.g., in the bone) into the brain.

Apart from the use of sun therapy for the cure of many skin diseases and disorders of bygone days, nowadays artificial light sources of a narrowband (NB) ultraviolet-B (UV–B) have effectively revolutionized the treatment of such skin diseases. The crucial role of gadolinium (Gd3+) ions in calcium-based hosts lies in their narrowband emission spectrum, specifically at 311–315 nm, attributed to the 6P7/2 to 8S7/2 transition. Calcium-based materials, known for their chemical stability, facilitate Gd3+ embedding, enabling UV activation and express emission in the narrowband range. This emission spectrum is well-suited for skin treatments, aligning with the action spectrum of various skin diseases. Gd3+ activated host materials in fluorescent lamps are considered prime sources of NB-UVB emissions. Calcium-based host materials are proving to be popular environments for embedding of dopants for such emissions. Calcium-based phosphor materials are leading the research in phototherapy applications due to their strong UV-B emissions, especially when activated by Gd3+ ions. Applications of phosphor host materials of this nature are generally chemically and thermally stable, have a low synthesis temperature and which produce enhanced NB-UVB emissions specifically suited for phototherapy lamps. This paper is a review of calcium -based phosphor host materials in Gd3+ activated materials or through energy transfers from sensitized dopant ions for enhanced NB-UVB emissions that is pertinent for treatments of many skin diseases such as psoriasis, vitiligo, eczema, and many other skin conditions.

Gadolinium-based contrast agents are increasingly used in clinical practice. While these pharmaceuticals are verified causal agents in nephrogenic systemic fibrosis, there is a growing body of literature supporting their role as causal agents in symptoms associated with gadolinium exposure after intravenous use and encephalopathy following intrathecal administration. Gadolinium-based contrast agents are multidentate organic ligands that strongly bind the metal ion to reduce the toxicity of the metal. The notion that cationic gadolinium dissociates from these chelates and causes the disease is prevalent among patients and providers. We hypothesize that non-ligand-bound (soluble) gadolinium will be exceedingly low in patients. Soluble, ionic gadolinium is not likely to be the initial step in mediating any disease. The Kidney Institute of New Mexico was the first to identify gadolinium-rich nanoparticles in skin and kidney tissues from magnetic resonance imaging contrast agents in rodents. In 2023, they found similar nanoparticles in the kidney cells of humans with normal renal function, likely from contrast agents. We suspect these nanoparticles are the mediators of chronic toxicity from magnetic resonance imaging contrast agents. This article explores associations between gadolinium contrast and adverse health outcomes supported by clinical reports and rodent models.

This study explores the microstructural characteristics of gadolinium (Gd)-rich phases in titanium (Ti) alloys through comprehensive electron microscopy analysis. The Ti alloys were produced using plasma arc melting and subsequently hot-forged. Elaborate material characterization, including scanning electron microscopy, electron backscatter diffraction, and energy dispersive spectroscopy, revealed the formation of round or angular Gd oxides and elongated Gd-rich grains within the alloy. High-magnification transmission electron microscopy and X-ray diffraction confirmed the presence of the FCC-type γ-Gd phase, influenced by the oxygen intake during casting, coexisting with Gd2O3 due to their similar crystal structures. The study also observed internal twins in the Gd grains, potentially delaying the transformation to the stable α-Gd phase. The significant mechanical property differences between the Gd-rich phases and the Ti matrix caused defects at phase interfaces during hot processing, weakening the Gd phase. This work enhances the understanding of Gd phase formation and its implications on the mechanical properties of Ti–Gd alloys.

PurposeTo demonstrate and evaluate factors contributing to near-cures in patients with Gadolinium Deposition Disease (GDD) undergoing intravenous (IV) DTPA chelation.MethodsPatients who had undergone or are currently undergoing DTPA chelation for GDD were included in this report based on their medical records that showed their perceived improvement was at least 80% back to normal. A survey was developed that included factors commonly reported by patients treated in one clinic to determine if these ‘near-cured’ (pre-MRI baseline health) individuals possessed certain factors and lacked others. The anonymized survey was emailed to these individuals by the principal treating physician, the only investigator not blinded to the subjects. This report describes clinical documentation of patient status and their underlying factors in individuals treated by the primary author, and no research was performed. The survey was sent to sixteen individuals; Fourteen patients completed it (10 females; 41.1 ± 11.2 y/o).ResultsThe most common factor was the administration of ≤5 lifetime doses of a Gadolinium-Based Contrast Agents (GBCA) (12/14). Unconfounded agents triggering GDD were seen in nine subjects. Most subjects (12/14) initiated chelation in the first year after the causative GBCA, and most (11/14) underwent ≤10 chelations with DTPA. Good healthcare status prior to MRI was observed in 5 subjects. The majority (11/14) described their immune status as strong. Severe physical disability prior to chelation was seen in 1.ConclusionSubjects with GDD can experience near-cure with IV DTPA chelation. Factors surveyed that predict near-cure include the start of chelation in the first year, few GBCA administrations, and good health status before MRI with GBCA injection. Nonetheless, a few patients with predictors of less successful outcomes still experienced near-cure.

The microstructure of virgin and heavy ion-irradiated Ce1–xGdxO2–x/2 with a wide range of Gd dopant concentrations (0 ≤ xGd ≤ 0.5) was evaluated by x-ray diffraction (XRD), micro-Raman spectroscopy, and transmission electron microscopy (TEM) for selected area electron diffraction (SAED) analysis and plane-view bright-field (BF) imaging of ion tracks. The Ce1–xGdxO2–x/2 samples were irradiated with 200-MeV Xe14+ ions up to fluences from 3 × 1011 to 1 × 1013 cm−2 at ambient temperature. XRD patterns of the virgin Ce1–xGdxO2–x/2 samples showed saturation of lattice parameter and relaxation of microstrain in Ce1–xGdxO2–x/2 which are attributed to the increasing Gd concentration. Moreover, micro-Raman spectroscopy and SAED patterns revealed the bixbyite (C-type) structure formation and oxygen vacancy ordering for xGd > 0.2 that is induced by dispersed C-type domains in the fluorite-structured (F-type) matrix. In the irradiated samples, asymmetric XRD peaks induced by lattice distortion were observed together with ion tracks in BF-TEM images. The radiation damage was recovered with the increase of Gd concentration. There is a rapid reduction of radiation damage cross section for xGd > 0.2 with a reduction of the C-type structure reflections in XRD and SAED patterns. [ABSTRACT FROM AUTHOR]

The microstructure of virgin and heavy ion-irradiated Ce1–xGdxO2–x/2 with a wide range of Gd dopant concentrations (0 ≤ xGd ≤ 0.5) was evaluated by x-ray diffraction (XRD), micro-Raman spectroscopy, and transmission electron microscopy (TEM) for selected area electron diffraction (SAED) analysis and plane-view bright-field (BF) imaging of ion tracks. The Ce1–xGdxO2–x/2 samples were irradiated with 200-MeV Xe14+ ions up to fluences from 3 × 1011 to 1 × 1013 cm−2 at ambient temperature. XRD patterns of the virgin Ce1–xGdxO2–x/2 samples showed saturation of lattice parameter and relaxation of microstrain in Ce1–xGdxO2–x/2 which are attributed to the increasing Gd concentration. Moreover, micro-Raman spectroscopy and SAED patterns revealed the bixbyite (C-type) structure formation and oxygen vacancy ordering for xGd > 0.2 that is induced by dispersed C-type domains in the fluorite-structured (F-type) matrix. In the irradiated samples, asymmetric XRD peaks induced by lattice distortion were observed together with ion tracks in BF-TEM images. The radiation damage was recovered with the increase of Gd concentration. There is a rapid reduction of radiation damage cross section for xGd > 0.2 with a reduction of the C-type structure reflections in XRD and SAED patterns. [ABSTRACT FROM AUTHOR]

The impact of Gd addition on the structural and magnetic properties of L 1 0 -FePt alloy thin films, which were sputter-deposited on MgO(001) substrates at 800 ° C, was investigated. A rapid deterioration of L 1 0 chemical ordering along with a strong amorphization effect is observed with addition of Gd. At more than 20 at. % Gd, additional crystalline phases occur. Due to the diminishing L 1 0 chemical order, the perpendicular magnetic anisotropy (PMA) gets strongly reduced from about 3 down to 1 MJ/m 3 with addition of 14 at. % Gd. For higher Gd concentrations, the easy axis of magnetization turns fully in-plane due to dominating magnetic shape anisotropy. Furthermore, the saturation magnetization gets reduced with Gd addition due to the antiferromagnetic coupling between the Fe and Gd magnetic moments. Also, the Curie temperature can be lowered. Interestingly, with addition of Gd, a change in film morphology takes place, changing from an isolated island structure to a more continuous film morphology, which is of particular interest for samples with low Gd concentration as these films exhibit still strong PMA but rather low coercive fields. [ABSTRACT FROM AUTHOR]

Ceramics from cerium-doped quintuple garnet-type compounds (Gd,Y,Lu)3Al2Ga3O12:Ce with different contents of Y and Lu have been fabricated and studied as a prospective scintillating material enabling improvement of scintillation properties by tuning of the composition of the matrix-forming crystalline compound. The coprecipitation method was applied to produce powders of complex garnet compounds, which were subsequently compacted and sintered. The influence of the matrix composition on photoluminescence and scintillation of the ceramics is studied using luminescence spectroscopy at steady state and pulsed excitation. Partial substitution of Lu by Y ions was found to be an effective tool for tailoring of scintillation properties of the material. A light yield of the Gd2Y0.5Lu0.5Al2Ga3O12 composition was measured to be 41 000 ph/MeV, whereas a scintillation kinetics was measured to have dominant fast scintillation components: 14 ns (84%) and 78 ns (16%). [ABSTRACT FROM AUTHOR]

BACKGROUND: Gadolinium enhancement of spinal nerve roots on magnetic resonance imaging (MRI) has rarely been reported in spinal dural arteriovenous fistula (SDAVF). Nerve root enhancement and cerebrospinal fluid (CSF) pleocytosis can be deceptive and lead to a misdiagnosis of myeloradiculitis. We report a patient who was initially diagnosed with neurosarcoid myeloradiculitis due to spinal nerve root enhancement, mildly inflammatory cerebrospinal fluid, and pulmonary granulomas, who ultimately was found to have an extensive symptomatic SDAVF. CASE PRESENTATION: A 52-year-old woman presented with a longitudinally extensive spinal cord lesion with associated gadolinium enhancement of the cord and cauda equina nerve roots, and mild lymphocytic pleocytosis. Pulmonary lymph node biopsy revealed non-caseating granulomas and neurosarcoid myeloradiculitis was suspected. She had rapid and profound clinical deterioration after a single dose of steroids. Further work-up with spinal angiography revealed a thoracic SDAVF, which was surgically ligated leading to clinical improvement. CONCLUSIONS: This case highlights an unexpected presentation of SDAVF with nerve root enhancement and concurrent pulmonary non-caseating granulomas, leading to an initial misdiagnosis with neurosarcoidosis. Nerve root enhancement has only rarely been described in cases of SDAVF; however, as this case highlights, it is an important consideration in the differential diagnosis of non-inflammatory causes of longitudinally extensive myeloradiculopathy with nerve root enhancement. This point is highly salient due to the importance of avoiding misdiagnosis of SDAVF, as interventions such as steroids or epidural injections used to treat inflammatory or infiltrative mimics may worsen symptoms in SDAVF. We review the presentation, diagnosis, and management of SDAVF as well as a proposed diagnostic approach to differentiating SDAVF from inflammatory myeloradiculitis.

ObjectiveGadolinium-based contrast agents (GBCAs) have been widely used to better visualize disease in brain magnetic resonance imaging (MRI). However, gadolinium deposition within the brain and body has raised safety concerns about the use of GBCAs. Therefore, the development of novel approaches that can decrease or even eliminate GBCA exposure while providing similar contrast information would be of significant use clinically.MethodsIn this work, we present a deep learning based approach for contrast-enhanced T1 synthesis on brain tumor patients. A 3D high-resolution fully convolutional network (FCN), which maintains high resolution information through processing and aggregates multi-scale information in parallel, is designed to map pre-contrast MRI sequences to contrast-enhanced MRI sequences. Specifically, three pre-contrast MRI sequences, T1, T2 and apparent diffusion coefficient map (ADC), are utilized as inputs and the post-contrast T1 sequences are utilized as target output. To alleviate the data imbalance problem between normal tissues and the tumor regions, we introduce a local loss to improve the contribution of the tumor regions, which leads to better enhancement results on tumors.ResultsExtensive quantitative and visual assessments are performed, with our proposed model achieving a PSNR of 28.24 dB in the brain and 21.2 dB in tumor regions.Conclusion and significanceOur results suggest the potential of substituting GBCAs with synthetic contrast images generated via deep learning.

The amygdaloid complex, including the basolateral nucleus (BLA), contributes crucially to emotional and cognitive brain functions, and is a major target of research in both humans and rodents. However, delineating structural amygdala plasticity in both normal and disease-related contexts using neuroimaging has been hampered by the difficulty of unequivocally identifying the boundaries of the BLA. This challenge is a result of the poor contrast between BLA and the surrounding gray matter, including other amygdala nuclei. Here, we describe a novel diffusion tensor imaging (DTI) approach to enhance contrast, enabling the optimal identification of BLA in the rodent brain from magnetic resonance (MR) images. We employed this methodology together with a slice-shifting approach to accurately measure BLA volumes. We then validated the results by direct comparison to both histological and cellular-identity (parvalbumin)-based conventional techniques for defining BLA in the same brains used for MRI. We also confirmed BLA connectivity targets using DTI-based tractography. The novel approach enables the accurate and reliable delineation of BLA. Because this nucleus is involved in and changed by developmental, degenerative and adaptive processes, the instruments provided here should be highly useful to a broad range of neuroimaging studies. Finally, the principles used here are readily applicable to numerous brain regions and across species.

This article presents a novel simulation approach for solving the inverse problem of kinetic heterogeneity in polymerization processes, specifically focusing on the production of polyisoprene using a gadolinium chloride solvate-based catalytic system. The proposed method is based on the assumption that the distribution of active centers (ACs) can be described by model distributions. By utilizing primary physicochemical data, such as the polymerization rate and molecular weight distribution, the simulation approach automatically identifies the kinetic parameters, determining the Frenkel statistical parameter and solving the problem of kinetic heterogeneity. The experimental results revealed the presence of at least three distinct types of ACs, each contributing different proportions to the polymerization process. The simulation approach offers valuable insights into the complexities of catalytic systems and their role in polymerization, paving the way for optimizing reaction conditions and advancing industrial polymer synthesis processes. This study marks a significant step forward in understanding and controlling polymerization reactions, with potential implications for the development of innovative materials and industrial applications.

Thermal properties characterizations for 10% and 15% Gd doped multi wall carbon nanotubes (MWCNTs) were investigated. TGA/DSC and TEM techniques were used for characterization. The features of mass loss characteristics for synthesized nanocomposite carbon nanomaterials were investigated. The specific heat capacities of the samples at a constant pressure increased as the temperature increased.

The design and synthesis of a Gd(III) metal–organic framework with the formula [Gd4(BTDI)3(DMF)4]n (JXUST-40, H4BTDI = 5,5′-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid) are reported hererin. Interestingly, a reversible single-crystal-to-single-crystal transition between JXUST-40 and {[Gd4(BTDI)3(H2O)4]·6H2O}n (JXUST-40a) was achieved under the stimulation of heat and solvents. Both JXUST-40 and JXUST-40a exhibited good stability when soaked in common solvents and aqueous solutions with pH values of 1–12. Magnetic studies showed that JXUST-40a has a larger magnetocaloric effect with –ΔS maxm = 26.65 J kg−1 K−1 at 2 K and 7 T than JXUST-40 due to its larger magnetic density. Structural analyses indicated that the coordinated solvent molecules play a crucial role in the coordination environment around the Gd(III) ions and the change in the framework, ultimately leading to the changes in the pore size and magnetism between JXUST-40 and JXUST-40a. In addition, both isomorphic [Dy4(BTDI)3(DMF)4]n (JXUST-41) and {[Dy4(BTDI)3(H2O)4]·6H2O}n (JXUST-41a) displayed slow magnetic relaxation behaviour. [ABSTRACT FROM AUTHOR]

Recently, there have been many researchers who discussed screen printing techniques (SPT) as a good approach to fabricate the thick films for gas sensor applications. In this work, the SPTs were conducted to fabricate the thick films based on gadolinium oxide-doped Fe2O3-LaFeO3-La2O3 that were applied as ethanol gas sensors. The crystal and morphological structures were investigated using x-ray diffraction and scanning electron microscopy, respectively. It shows that there are three phases of the crystal structure of gadolinium oxide-doped Fe2O3-LaFeO3-La2O3 i.e., rhombohedral, orthorhombic, and hexagonal. The morphological structure shows an average particle size of about 0.61 pm. Furthermore, the electrical properties measurements were explored to ensure the performance of thick films in detecting the ethanol gases. Th measurements were conducted in the range of temperature of about 310 °C to 325 °C and in the various ethanol gas containing, it is 0 ppm, 100 ppm, 200 ppm, and 300 ppm. This result showed that the highest response of thick films in the existence of ethanol gases (300 ppm) is 427 with an optimum temperature of 319 °C. It is also confirmed that SPT has an excellent approach in thick film fabrication to produce gas sensor devices with good performance. [ABSTRACT FROM AUTHOR]

Bi0.5Na0.5TiO3 (BNT) is a lead-free ferroelectric ceramic that has received much attention in recent years. However, the pure BNT presents a tetragonal structure with considerable remanent polarization at room temperature, which lead to its low energy storage efficiency thus limiting its application in energy storage. In this paper, on the basis of the introduction of Ba0.3Sr0.7TiO3 (BST), NaNbO3 (NN) into BNT to form a relaxor ferroelectric, Gd2O3 is further doped to refine grain and reduce oxygen vacancy concentration thereby improving the breakdown strength, which is beneficial to improve its energy storage performance. A series of ceramic samples of 0.9 (0.5BNT-0.5BST)-0.1NN + xwt%Gd (x = 0, 0.5, 1, 2.5, 3) were prepared by the solid-state reaction method. The effect of Gd2O3 on the microstructure and electrical properties of the systems was investigated. The results show that a suitable doping level of Gd2O3 can significantly refine the grains and improve the breakdown strength of the system. For x = 2.5 ceramic sample obtained a high energy storage density of Wrec = 4.86 J/cm3 and an energy storage efficiency of η = 86% at 250 kV/cm. Furthermore, this sample exhibited a stable discharge density (Wd ≥ 1.44 J/cm3) and an ultra-fast discharge rate (t0.9 ≤ 0.056 µs) in the temperature range of 140 kV/cm, 40∼140 °C. [ABSTRACT FROM AUTHOR]

Inflammation plays a key role in pathogenesis and rupture of aneurysms. Non-invasively and dynamically monitoring aneurysm inflammation is critical. This study evaluated myeloperoxidase (MPO) as an imaging biomarker and therapeutic target for aneurysm inflammation using an elastase-induced rabbit model treated with or without 4-aminobenzoic acid hydrazide (ABAH), an irreversible inhibitor of MPO. Myeloperoxidase-sensitive magnetic resonance imaging (MRI) using Mn-TyrEDTA, a peroxidase activity-dependent contrast agent, revealed weak contrast enhancement in contralateral arteries and decreased contrast enhancement in aneurysm walls with ABAH treatment, indicating MPO activity decreased and inflammation mitigated. This was supported by reduced immune cell infiltration, matrix metalloproteinases (MMP-2 and − 9) activity, ROS production and arterial wall destruction on histology. Finally, the aneurysm expansion rate remained < 50% throughout the study in the ABAH(+) group, but increased gradually in the ABAH(-) group. Our results suggest that inhibition of MPO attenuated inflammation and expansion of experimental aneurysm and MPO-sensitive MRI showed promise as a noninvasive tool for monitoring aneurysm inflammation. [ABSTRACT FROM AUTHOR]

Ce-doped gadolinium gallium aluminum oxide (Ce: GGAG) precursors were first prepared by the microwave-assisted homogeneous precipitation method (MAHP). Thermal gravity-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), specific surface area analysis (BET) and field emission scanning electron microscopy (FE-SEM) were employed to investigate the crystal structure, phase evolution and morphologies of the Ce: GGAG precursors and powders. The influence of Ga ion concentration in the salt solution on the properties of Ce: GGAG powders was investigated. All the precursors were transformed into single-phase GGAG after being calcined at 950 °C in a furnace for 3 h. Monodispersed Ce: GGAG powders were obtained as the Ga ion concentration was lower than 0.06 mol/L. Single-phase and dense Ce: GGAG ceramics were obtained after sintering at 1600 °C in a flowing oxygen atmosphere for 10 h. Specifically, the Ce: GGAG ceramic reached its maximum density of ~6.68 g/cm3, which was close to its theoretical density of 6.70 g/cm3, and exhibited the highest optical transmittance of 65.2% at 800 nm after hot isostatic pressing sintering (HIP) as the Ga ion concentration was 0.02 mol/L. The decay time and light yield of the GGAG ceramic were 35 ns and 35,000 ± 1250 ph/MeV, respectively, suggesting that Ce: GGAG ceramics prepared using MAHP-synthesized nanopowders are promising for scintillation applications. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rice, a pivotal global food staple, annually accumulates vast amounts of rice husks, resulting in substantial environmental impact. Exploiting the high silica content in rice husk, our research aimed to recycle this agricultural byproduct to synthesize mesoporous silica nanoparticles (rMSNs). These nanoparticles were further modified to evaluate their potential as effective carriers for cancer drug delivery. RESULTS: rMSNs showed high biocompatibility, large surface area and porous structure as MSNs, making them excellent drug carriers. Further modifications were applied to rMSNs, such as the incorporation of the lanthanides europium and gadolinium into rMSNs, making them fluorescent and magnetic for detection and tracking using confocal fluorescence microscopy and magnetic resonance imaging. Additionally, folic acid and aptamer AS1411 were conjugated with rMSNs to enhance the targeting of cancer cells. HeLa cells exhibited higher uptake of camptothecin (CPT)‐loaded rMSNs compared to normal fibroblast cells (L929). The linkage of disulfide bonds to rMSNs also allowed CPT to be carried by rMSNs and released intracellularly in the presence of the abundant reducing agent glutathione. The validation of rMSNs in vitro and in vivo proved their practical feasibility. CONCLUSION: Our findings indicate that low‐cost rMSNs, derived from recycled agricultural waste, can replace highly valuable MSNs. Functionalized rMSNs exhibit promising capabilities in transporting clinical drugs to specific aberrant tissues and offering dual‐targeting and dual‐imaging functionalities for enhanced cancer therapy. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A new ibuprofen derivative, (E)-2-(4-isobutylphenyl)-N′-(4-oxopentan-2-ylidene) propane hydrazide (IA), was synthesized, along with its metal complexes with Co, Cu, Ni, Gd, and Sm, to investigate their anti-inflammatory efficacy and COX-2 inhibition potential. Comprehensive characterization, including 1H NMR, MS, FTIR, UV–vis spectroscopy, and DFT analysis, were employed to determine the structural configurations, revealing unique motifs for Gd/Sm (capped square antiprismatic/tricapped trigonal prismatic) and Cu/Ni/Co (octahedral) complexes. Molecular docking with the COX-2 enzyme (PDB code: 5IKT) and pharmacokinetic assessments through SwissADME indicated that these compounds have superior binding energies and pharmacokinetic profiles, including BBB permeability and gastrointestinal absorption, compared to the traditional ibuprofen standalone. Their significantly lower IC50 values further suggest a higher efficacy as anti-inflammatory agents and COX-2 inhibitors. These research findings not only introduce promising ibuprofen derivatives for therapeutic applications but also set the stage for future validation and exploration of this new generation of ibuprofen compounds. [ABSTRACT FROM AUTHOR]

In this paper, the influence of pump radiation parameters and laser resonator configurations on the characteristics of high-energy 589 nm KGW Raman lasers is investigated and explained. The best energy efficiency is obtained in lasers with a flat resonator, while the best angular characteristics are obtained in lasers with an unstable resonator. The use of stable spherical resonators results in the worst energy and angular characteristics. The angular divergence in lasers with flat cavities increases with pump intensity because of wing growth, whereas the core width remains unchanged. The structure of the wings is recorded and analyzed. [ABSTRACT FROM AUTHOR]

Novel nanogels, characterized by high stability and incorporating macrocyclic chelates of Gd(III) and Dy(III), were synthesized and assessed for their effectiveness as T1 and T2 relaxation agents, respectively. In this specific design, we employed octacoordinated bifunctional Gd‐1,7‐DOTAGA2 chelate to cross‐link chitosan chains. The results revealed that the sample exhibited a relaxivity value at clinical magnetic field strengths (1.5 T), approximately seven times higher than that of currently available clinical contrast agents and good MRI contrast efficacy at both 7.1 and 1 T. Furthermore, the nanogel displayed excellent stability in biological fluids, with no discernible interactions with serum biomolecules and no release of metal. In addition to Gd(III)‐based probes commonly used as T1 positive contrast agents, the nanogel with the corresponding Dy‐1,7‐DOTAGA2 chelate was prepared to explore its potential as a T2 MRI probe. Dy‐based nanogel demonstrated notably elevated transverse relaxivity values compared to the free chelate at high magnetic fields (>3 T) and significant T2 MRI contrast at 7.1 T, a capability often lacking when employing an equivalent concentration of a low‐molecular‐weight Dy(III) complex. The characterization of paramagnetic complexes was completed through the measurement of 1H NMRD profiles and 17O NMR data. [ABSTRACT FROM AUTHOR]

Gadolinium‐based complex contrast agents (GBCAs), frequently applied in magnetic resonance imaging (MRI), are associated with severe acute anaphylactic shock and incurable nephrogenic systemic fibrosis. Besides, the repeated use of GBCAs may result in the accumulation in various tissues. Given these potential adverse effects, GBCAs have not been well used during pregnancy. Herein, a novel metal‐free T2‐weighted MRI nanoprobe, designated fluorinated small‐sized graphene oxide with optimized fluorine content (LF‐sGO), is developed via graphene oxide materials. By introducing specific polar C─F bonds onto the small‐sized graphene oxide (sGO) skeleton, the prepared nanoprobe exhibits excellent water solubility, as well as superior MRI capabilities, thereby furnishing high‐resolution MRI anatomical information. Furthermore, the free radicals on LF‐sGO stabilized by C─F bonds confer LF‐sGO enrichment in the tumor region, enabling comprehensive imaging capability. The cytotoxicity study in vitro indicates that LF‐sGO has the potential to serve as a biocompatible imaging probe. Moreover, detailed in vivo studies on pregnant mice and zebrafish adequately demonstrate that microinjection of LF‐sGO does not induce dysontogensis and teratogenesis. This study successfully showcases a metal‐free nanoprobe that exhibits exceptional MRI capabilities for the purpose of tumor diagnosis. Notably, this nanoprobe holds promise for safe and effective tumor diagnosis during pregnancy. [ABSTRACT FROM AUTHOR]

Studying the effect of morphology on the circularly polarized luminescence (CPL) of chiral molecular materials is important for the development of CPL-active materials for applications. Herein, we report that the morphology of Gd(NO3)3/R-,S-AnempH2 [AnempH2 = (1-anthrylethylamino)methylphosphonic acid] assemblies can be controlled by solvent modulation to form spiral bundles Gd(R-,S-AnempH)3·2H2O (R-,S-1), crystals Gd(R-,S-AnempH)3·2H2O (R-,S-2) and spindle-shaped particles Gd(R-,S-AnempH)3·3H2O·0.5DMF (R-,S-3) with similar chain structures. Interestingly, R-,S-1 are CPL active and show the highest value of dissymmetric factor among the three pairs of enantiomers (‖glum‖ = 2.1 × 10–3), which is 2.8 times larger than that of R-,S-2 , while R-,S-3 are CPL inactive with ‖glum‖ ≈ 0. This work provides a new route to control the morphology of chiral coordination polymers and improve their CPL performance. [ABSTRACT FROM AUTHOR]

Dark-blood late gadolinium enhancement (LGE) has been shown to improve the visualization and quantification of areas of ischemic scar compared to standard bright-blood LGE. Recently, the performance of various semi-automated quantification methods has been evaluated for the assessment of infarct size using both dark-blood LGE and conventional bright-blood LGE with histopathology as a reference standard. However, the impact of this sequence on different quantification strategies in vivo remains uncertain. In this study, various semi-automated scar quantification methods were evaluated for a range of different ischemic and non-ischemic pathologies encountered in clinical practice. A total of 62 patients referred for clinical cardiovascular magnetic resonance (CMR) were retrospectively included. All patients had a confirmed diagnosis of either ischemic heart disease (IHD; n = 21), dilated/non-ischemic cardiomyopathy (NICM; n = 21), or hypertrophic cardiomyopathy (HCM; n = 20) and underwent CMR on a 1.5 T scanner including both bright- and dark-blood LGE using a standard PSIR sequence. Both methods used identical sequence settings as per clinical protocol, apart from the inversion time parameter, which was set differently. All short-axis LGE images with scar were manually segmented for epicardial and endocardial borders. The extent of LGE was then measured visually by manual signal thresholding, and semi-automatically by signal thresholding using the standard deviation (SD) and the full width at half maximum (FWHM) methods. For all quantification methods in the IHD group, except the 6 SD method, dark-blood LGE detected significantly more enhancement compared to bright-blood LGE (p < 0.05 for all methods). For both bright-blood and dark-blood LGE, the 6 SD method correlated best with manual thresholding (16.9% vs. 17.1% and 20.1% vs. 20.4%, respectively). For the NICM group, no significant differences between LGE methods were found. For bright-blood LGE, the 5 SD method agreed best with manual thresholding (9.3% vs. 11.0%), while for dark-blood LGE the 4 SD method agreed best (12.6% vs. 11.5%). Similarly, for the HCM group no significant differences between LGE methods were found. For bright-blood LGE, the 6 SD method agreed best with manual thresholding (10.9% vs. 12.2%), while for dark-blood LGE the 5 SD method agreed best (13.2% vs. 11.5%). Semi-automated LGE quantification using dark-blood LGE images is feasible in both patients with ischemic and non-ischemic scar patterns. Given the advantage in detecting scar in patients with ischemic heart disease and no disadvantage in patients with non-ischemic scar, dark-blood LGE can be readily and widely adopted into clinical practice without compromising on quantification. [ABSTRACT FROM AUTHOR]

Burnable absorbers play an important role in nuclear reactor safety and exploring their effect on the reactor core behavior is an important issue in the design and operation of the reactor core. The aim of the present work was to discover the effect of burnable absorbers on criticality and reactivity coefficient of VVER-1000 assembly. The calculations were conducted with a 3-D Monte Carlo transport code MCNP6 and ENDF/B-VII.1 nuclear library. The Gd2O3 content varying from 0 wt.% to 8 wt.% was considered to complete the inter-comparison analysis between the criticality and the reactivity coefficients for three UO2+Gd2O3 fuel configurations. At the beginning of the cycle, there is a significant difference between the criticality (kinf) of assembly with and without Gd2O3, however, at the middle of the cycle those differences become very small and almost the same at the end of the cycle. The Dopp ler temperature coefficient values are always sufficiently negative and demonstrate a more negative trend with increasing gadolinium concentrations and fuel burnup. At beginning of the cycle, the moderator temperature coefficient value increases negatively as gadolinium concentration increases but, at middle of the cycle this trend does not occur. The fuel composition is predicted to be the reason behind this situation. At the end of cycle, there is no clear trend in the moderator temperature coefficient values with respect to Gd2O3 concentration. The absorbing effect of Gd2O3 appears to have diminished significantly. Overall, this research provides insights into the influence of the burnable absorbers on the neutronic parameters of the VVER-1000 assembly and its contribution to reactor safety. [ABSTRACT FROM AUTHOR]

We synthesized pure and doped gadolinium, samarium, and chromium LaFeO3 denoted as LFO, LFCO, LGFCO, and LSFCO, respectively, employing a straightforward, cost-effective, and environmentally friendly solid-state method. The resulting samples were characterized through powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), and UV–Visible absorption measurements. The PXRD findings affirmed that the phase structures corresponding to LFO, LFCO, LGFCO, and LSFCO manifested at an identical calcination temperature of 1200 °C, adopting orthorhombic systems. The calculated crystallite size for each sample, employing Debye-Scherrer's equation, ranged from 25 to 37 nm, with LGFCO and LSFCO exhibiting an augmented crystallite size. This enhancement can be attributed to the integration of dopants into the LaFeO3 lattice, facilitating crystallite growth. SEM images portrayed microstructure composed of fine particle sizes and pseudo-spherical morphology, and the stoichiometry of La, Fe, and O in LFO was confirmed by energy dispersive spectroscopy (EDS). Reduction in the band gap was ascribed to the doping effect, with LGFCO exhibiting the lowest band gap value. Notably, this ceramic material demonstrated the highest photocatalytic activity for methylene blue degradation under sunlight radiation, surpassing the performance of the other examined samples. [ABSTRACT FROM AUTHOR]

This work reports an optimized method to experimentally quantify the Gd-nanoparticle dose enhancement generated by electronic brachytherapy. The dose enhancement was evaluated considering energy beams of 50 kVp and 70 kVp, determining the Gd-nanoparticle concentration ranges that would optimize the process for each energy. The evaluation was performed using delaminated radiochromic films and a Poly(methyl methacrylate) (PMMA) phantom covered on one side by a thin 2.5 μ m Mylar filter acting as an interface between the region with Gd suspension and the radiosensitive film substrate. The results for the 70 kVp beam quality showed dose increments of 6 ± 6 % , 22 ± 7 % , and 9 ± 7 % at different concentrations of 10, 20, and 30 mg/mL, respectively, verifying the competitive mechanisms of enhancement and attenuation. For the 50 kVp beam quality, no increase in dose was recorded for the concentrations studied, indicating that the major contribution to enhancement is from the K-edge interaction. In order to separate the contributions of attenuation and enhancement to the total dose, measurements were replicated with a 12 μ m Mylar filter, obtaining a dose enhancement attributable to the K-edge of 29 ± 7 % and 34 ± 7 % at 20 and 30 mg/mL, respectively, evidencing a significant additional dose proportional to the Gd concentration. [ABSTRACT FROM AUTHOR]

Objectives: Heart failure with preserved ejection fraction (HFpEF) is a syndrome with significant clinical heterogeneity. Myocardial fibrosis has been considered a common pathological process in the development and progress of HFpEF. This study aimed to consolidate data on the prognostic effect of myocardial fibrosis, evaluated by cardiovascular magnetic resonance (CMR) imaging in patients with HFpEF. Methods: Three medical databases were searched for potentially related articles up to February 28, 2023. Cohort studies reporting associations between myocardial fibrosis and risk of all-cause mortality or composite major adverse cardiac outcomes (MACE) were included. Cardiac fibrosis was evaluated by CMR metrics, including late gadolinium enhancement (LGE) or myocardial extracellular volume (ECV). The hazard ratios (HRs) and 95% confidence intervals (CI) of the outcomes for higher myocardial fibrosis were calculated. Results: Twelve studies with 2787 patients with HFpEF were included for analysis. After a median follow-up duration of 31.2 months, a higher level of cardiac fibrosis was associated with a significant increase in the risk of MACE (HR = 1.34, 95% CI = 1.14–1.57) and all-cause mortality (HR = 1.74, 95% CI = 1.27–2.39), respectively. Furthermore, the increased risk of outcomes was both observed when cardiac fibrosis was defined according to LGE or ECV, respectively. Conclusions: Higher burden of myocardial fibrosis evaluated by CMR can predict a poor prognosis in patients with HFpEF. Evaluation of LGE or ECV based on CMR could be recommended in these patients for risk stratification and guiding further treatment. Clinical relevance statement: Inclusion of cardiovascular magnetic resonance examination in the diagnostic and risk-evaluation algorithms in patients with heart failure with preserved ejection fraction should be considered in clinical practice and future studies. Key Points: • Myocardial fibrosis is a common pathological process in heart failure with preserved ejection fraction. • A higher myocardial fibrosis burden on cardiac magnetic resonance predicts a poor prognosis in patients with heart failure with preserved ejection fraction. • Evaluation of myocardial fibrosis may be useful in patients with heart failure with preserved ejection fraction for risk stratification and treatment guidance. [ABSTRACT FROM AUTHOR]

Objective: The aims of our study were to investigate the effect of the extent and location of late gadolinium enhancement (LGE) on the left atrium (LA) function in patients with acute myocarditis (AM) using cardiovascular magnetic resonance (CMR). Method: This retrospective study performed CMR scans in 113 consecutive patients (89 males, 24 females; mean age 45.8 ± 17.3 years) with AM that met the updated Lake Louise criteria. Reservoir, conduit, and booster LA functions were analyzed by CMR feature tracking using dedicated software. Besides LA strain measurements, myocardial scar location and extent were assigned and quantified by LGE imaging. Results: AM patients with septal LGE had impaired reservoir, conduit, and conduit strain rate function in comparison with AM patients with non-septal LGE (p = 0.001, for all). In fully adjusted multivariable linear regression, reservoir and conduit were significantly associated with left ventricle (LV) LGE location (β coefficient = 8.205, p = 0.007; β coefficient = 5.185, p = 0.026; respectively). In addition, LA parameters decreased according to the increase in the extent of LV fibrosis (LGE ≤ 10%; LGE 11–19%; LGE ≥ 20%). After adjustment in multivariable linear regression, the association with LV LGE extent was no longer statistically significant. Conclusion: In patients with acute myocarditis, LA function abnormalities are significantly associated with LV LGE location, but not with LGE extent. Septal LGE is paralleled by a deterioration of LA reservoir and conduit function. Clinical relevance statement: Left atrium dysfunction is associated with the presence of late gadolinium enhancement in the left ventricle septum and can be useful in the clinical prognostication of patients with acute myocarditis, allowing individually tailored treatment. Key Points: • Myocardial fibrosis is related to atrial impairment. • The location of myocardial fibrosis is the main determinant of atrial dysfunction in myocarditis patients. • The quantification of atrial mechanisms may provide more in-depth insight into myocarditis pathophysiology. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is the most sensitive technique for detecting inflammatory demyelinating lesions in multiple sclerosis (MS) and plays a crucial role in diagnosis and monitoring treatment effectiveness, and for predicting the disease course. In clinical practice, detection of MS lesions is mainly based on T2-weighted and contrast-enhanced T1-weighted sequences. Contrast-enhancing lesions (CEL) on T1-weighted sequences are related to (sub)acute inflammation, while new or enlarging T2 lesions reflect the permanent footprint from a previous acute inflammatory demyelinating event. These two types of MRI features provide redundant information, at least in regular monitoring of the disease. Due to the concern of gadolinium deposition after repetitive injections of gadolinium-based contrast agents (GBCAs), scientific organizations and regulatory agencies in Europe and North America have proposed that these contrast agents should be administered only if clinically necessary. In this article, we provide data on the mode of action of GBCAs in MS, the indications of the use of these agents in clinical practice, their value in MS for diagnostic, prognostic, and monitoring purposes, and their use in specific populations (children, pregnant women, and breast-feeders). We discuss imaging strategies that achieve the highest sensitivity for detecting CELs in compliance with the safety regulations established by different regulatory agencies. Finally, we will briefly discuss some alternatives to the use of GBCA for detecting blood–brain barrier disruption in MS lesions. Clinical relevance statement: Although use of GBCA at diagnostic workup of suspected MS is highly valuable for diagnostic and prognostic purposes, their use in routine monitoring is not mandatory and must be reduced, as detection of disease activity can be based on the identification of new or enlarging lesions on T2-weighted images. Key Points: • Both the EMA and the FDA state that the use of GBCA in medicine should be restricted to clinical scenarios in which the additional information offered by the contrast agent is required. • The use of GBCA is generally recommended in the diagnostic workup in subjects with suspected MS and is generally not necessary for routine monitoring in clinical practice. • Alternative MRI-based approaches for detecting acute focal inflammatory MS lesions are not yet ready to be used in clinical practice. [ABSTRACT FROM AUTHOR]

Thermal conductivity switching in Pd-catalyzed Gd hydride films was investigated using in situ analyses of electrical, optical, structural, and thermophysical properties upon gasochromic hydrogenation/dehydrogenation at room temperature. These reactions allow the films to reversibly switch between the metallic (GdH2) phase in the hydrogenated state and the semiconductor (GdH3) phase in the dehydrogenated state. We fabricated three-layered films comprising Pd (5 nm)/Gd or GdH2 (300 nm)/Mo (100 nm) using DC magnetron sputtering using Pd, Gd, and Mo targets, respectively, on unheated synthetic quartz substrates. Ar or mixture of Ar + H2 (H2: 5 % to 50 %) gases were used for the deposition of the Gd or GdH2 films, respectively. The thermal conductivities of the Gd or GdH2 films were analyzed using in situ rear-heating/rear-detection type time-domain picosecond pulsed light heating thermoreflectance measurements by employing a gas mixture of N2/Ar and H2 (H2: 3 %) at 1 atm, which is below the explosive limit for hydrogen. The thermal conductivities of Gd and GdH2 films were measured for one and two hydro-/dehydrogenation cycles, respectively. The thermal switching ratios of the ON state thermal conductivity to the OFF state thermal conductivity were 6.4 and 2.9–5.4 for the Gd film and the GdH2 (H2: 5 %–50 %) films, respectively. The thermal conductivity of the Gd hydrides films changed along with those estimated from the Wiedemann–Franz Law and electrical conductivities. [ABSTRACT FROM AUTHOR]

A simple and feasible method is proposed in this study for the infiltration of gadolinium doped ceria (GDC) into both anode and cathode electrodes of microtubular solid oxide fuel cells (SOFCs) to improve the cell performance. Some crucial infiltration parameters are also systematically optimized according to electrochemical and microstructural investigations along with short-term lifetime tests. The results reveal that the cell performance can be significantly enhanced with nanoparticle GDC decoration. While the reference cell provides only 252.7 mW/cm2 peak power density under hydrogen fuel at 800 °C, the infiltrated cell with the optimized parameters shows 523.0 mW/cm2 maximum power density under the same testing conditions. The noteworthy improvement in the cell performance is found to be as a result of reduced electrode resistances due to increased number of active electrochemical reaction sites resulting from high surface area of nano GDC particles infiltrated as well as GDC being mixed conductor with high ionic conductivity. [ABSTRACT FROM AUTHOR]