Local Deposition Research Articles

Decoupling Distribution of n-Alkanes in Aeolian Sand and Vegetation of the Northern Ulan Buh Desert, China: Insight into Organic Matter Preservation in Arid Regions.

Fallen leaves and their decomposition directly deposit leaf wax n-alkanes into sediments, which can be used to identify local flora. These n-alkanes are important for studying past vegetation and climate, but their distribution in sediments must be known. Aeolian sand n-alkanes are particularly important for understanding paleoclimates in arid regions, despite the challenges of extraction due to their extremely low abundance. To investigate the preservation of plant leaf wax n-alkanes in deserts, we analyzed n-alkanes in aeolian sands from the Northern Ulan Buh Desert (UBD), China, and compared them to the surrounding vegetation. We calculated the total n-alkane concentration (ΣALK), average chain length (ACL21-35), and carbon preference index (CPI21-35). In the Northern UBD, aeolian sand n-alkanes have lower ΣALK, indicating microbial degradation. The eastern aeolian sand has lower CPI21-35 and ACL21-35 than the adjacent vegetation, whereas the western sand values are consistent with the plants, likely due to the transport of plant-derived materials by wind and water from the nearby mountains. Our study shows that sedimentary n-alkane signatures are not only determined by local vegetation but also influenced by environmental factors like temperature and precipitation. Additionally, local deposition processes play a significant role in determining the properties of these n-alkanes.

Evaluation of local erosion and deposition on the W-monoblock of JA-DEMO divertor

Evaluation of local erosion and deposition on the W-monoblock of JA-DEMO divertor

Atmospheric Mercury Concentrations and Isotopic Compositions Impacted by Typical Anthropogenic Mercury Emissions Sources.

Coal-fired power plants (CFPPs) and cement plants (CPs) are important anthropogenic mercury (Hg) emission sources. Mercury speciation profiles in flue gas are different among these sources, leading to significant variations in local atmospheric Hg deposition. To quantify the impacts of Hg emissions from CFPPs and CPs on local-scale atmospheric Hg deposition, this study determined concentrations and isotopes of ambient gaseous elemental mercury (GEM), particulate-bound mercury (PBM), and precipitation total Hg (THg) at multiple locations with different distances away from a CFPP and a CP. Higher concentrations of GEM and precipitation THg in the CFPP area in summer were caused by higher Hg emission from the CFPP, resulting from higher electricity demand. Higher concentrations of GEM, PBM, and precipitation THg in the CP area in winter compared to those in summer were related to the higher output of cement. Atmospheric Hg concentration peaked near the CFPP and CP and decreased with distance from the plants. Elevated GEM concentration in the CFPP area was due to flue gas Hg0 emissions, and high PBM and precipitation Hg concentrations in the CP area were attributed to divalent Hg emissions. It was estimated that Hg emissions from the CFPP contributed 58.3 ± 20.9 and 52.3 ± 25.9% to local GEM and PBM, respectively, and those from the CP contributed 47.0 ± 16.7 and 60.0 ± 25.9% to local GEM and PBM, respectively. This study demonstrates that speciated Hg from anthropogenic emissions posed distinct impacts on the local atmospheric Hg cycle, indicating that Hg speciation profiles from these sources should be considered for evaluating the effectiveness of emission reduction policies. This study also highlights the Hg isotope as a useful tool for monitoring environmental Hg emissions.

HYBRID METAL-SEMICONDUCTOR STRUCTURES BASED ON InP AND GaAs NANOTEMPLATES FOR ELECTRONIC AND PHOTONIC APPLICATIONS

In this scientific work are presented the results that contribute to solving an important scientific problem related to obtaining of porous templates with controlled morphology and design by replacing acidic and alkaline electrolytes, the use of which presents a danger for the environment, with neutral electrolyte (NaCl) as well as obtaining of the metal-semiconductor hybrid structures using pulsed electrodeposition that offers additional possibilities to control the localized deposition in certain portions of the porous template and allows the controlled fabrication of nanodots, nanowires, nanotubes and perforated metal nanomembranes. Mechanisms of pore propagation in InP and GaAs semiconductor substrates and electrochemical deposition of metals in the produced porous templates are identified and discussed, which allowed to control the direction of pore growth, including those parallel to the substrate surface as well as localized Au deposition.

Comparative analysis of structural characteristics and thermal insulation properties of ZrO2 thin films deposited via chemical and physical vapor phase processes

ZrO2 is a flagship material for the development of efficient thermal barrier coatings not only for aerospace applications but also on steel molds for plastic injection, especially to produce high quality miniaturized parts of low environmental impacts. In the present study, ZrO2 thin films of thicknesses ranging between 4 and 40 μm were deposited on steel substrates by two key gas phase technologies, magnetron sputtering (PVD) and direct liquid injection metal organic CVD (DLI-MOCVD). The film morphology, structure and chemical composition were comparatively investigated and correlated to their heat transfer properties. All films were nearly stoichiometric and presented a columnar structure mainly formed of the monoclinic crystalline phase. The magnetron sputtering coatings were denser and smoother than the CVD ones, for which highly porous tree-like microstructures were observed without degradation of their mechanical properties. All films exhibited efficient thermal insulation properties, the thickest 40 µm magnetron sputtering coating displaying the most significant reduction in heat transfer. The CVD films provided the highest thermal gradient decrease across their thickness, probably thanks to their higher porosity associated to a multi-angle tree-like columnar structure, both acting as scattering zones of phonons involved in heat flow diffusion. By controlling the local deposition conditions influencing the nucleation and growth mechanisms, the film porous microstructure can thus be tuned to optimize the coating thermal properties.

Photocatalytic Edge Growth of Conductive Gold Lines On Microstructured TiO2-ITO Substrates.

Titanium dioxide is well-known for its excellent photocatalytic properties. UV-controlled photodeposition of gold on TiO2 is achieved by photocatalytic reduction of precursor ions from a tetrachloroauric solution. During the growth process on the surface, clusters grow from nucleation centers and coalescence is observed for sufficiently long UV illumination times, resulting in gold structures with complex shapes. Here, we hypothesize and demonstrate that the growth process is altered by employing an ITO sublayer below the TiO2 layer. Photocatalytic gold growth experiments on a microstructured thin film stack of 6 nm ITO and 70 nm TiO2 lead to strongly localized gold growth along the edge of the patterned area. A conductive gold line with a height of 3.8 μm is achieved along the edge of the TiO2-coated region, while gold growth on the surface of TiO2 is effectively suppressed. For substrates coated only with ITO or TiO2, no edge growth is observed. Furthermore, for an 845 nm thick TiO2 layer, either with or without ITO sublayer, gold growth on the TiO2 surface is dominant. Thus, for the effective steering of electrons to the edge, both the ITO sublayer and a sufficiently thin TiO2 layer are necessary. This modified method of photocatalytic deposition─electrons photogeneration in a thin layer, collection in a dedicated conductive sublayer, and growth by reduction at a different position─opens opportunities for localized material deposition. We are in particular aiming at extending the toolbox of neuromorphic engineering by providing a technical implementation of stimulus-controlled dynamic formation of directional conductive interlinks.

A finite volume approach to dosimetric calculations in diffusing alpha-emitters radiation therapy

Objective.In diffusing alpha-emitters radiation therapy ('Alpha DaRT'), the diffusion-leakage (DL) model is used to determine the spatial distributions of the emitters and the corresponding alpha dose, critical for a successful treatment. This work first introduces a finite volume (FV) approach to develop numerical schemes to simulate the DL model in one, two and three dimensions then presents how variations over realistic ranges of the DL model parameters related to desorption, diffusion and leakage processes affect the alpha dose distribution and the position of the clinically significant alpha particle10Gy isodose. This work also presents the effects of three modeling approximations: two source geometry approximations (solid cylinder instead of hollow, pixelized cross section instead of circular), and one dosimetric approximation (single-source dose superposition instead of multiple-sources direct dose calculation).Approach.The introduced FV approach was used to obtain spatial distributions of the emitters, from which the corresponding alpha dose distributions were calculated under the assumption of a local deposition of the alpha particles' energies. Variation ranges of the DL model parameters were based on previously published data. For each modeling approximation studied, the error and relative error on the alpha dose distribution were calculated and the displacement of the10Gy isodose was evaluated.Main results.Over realistic ranges, the desorption probabilities, diffusion lengths, and leakage probabilities affect the position of the alpha particle10Gy isodose by∼0.1mm,∼1.5mm and∼0.5mm, respectively. The three modeling approximations studied have a negligible effect on the alpha particle10Gy isodose position, with displacements⩽0.01mm.Significance.This work quantitatively evaluates the relative importance of different parameters and approximations in Alpha-DaRT alpha dose calculations based on their impact not only on the dose variation at a given distance from the source but also on the displacement of clinically significant isodoses.

A Critical Analysis of the CFD-DEM Simulation of Pharmaceutical Aerosols Deposition in Upper Intra-Thoracic Airways: Considerations on Aerosol Transport and Deposition.

The reliability and accuracy of numerical models and computer simulations to study aerosol deposition in the human respiratory system is investigated for a patient-specific tracheobronchial tree geometry. A computational fluid dynamics (CFD) model coupled with discrete elements methods (DEM) is used to predict the transport and deposition of the aerosol. The results are compared to experimental and numerical data available in the literature to study and quantify the impact of the modeling parameters and numerical assumptions. Even if the total deposition compares very well with the reference data, it is clear from the present work how local deposition results can depend significantly upon spatial discretization and boundary conditions adopted to represent the respiratory act. The modeling of turbulent fluctuations in the airflow is also found to impact the local deposition and, to a minor extent, the flow characteristics at the inlet of the computational domain. Using the CFD-DEM model, it was also possible to calculate the airflow and particles splitting at bifurcations, which were found to depart from the assumption of being equally distributed among branches adopted by some of the simplified deposition models. The results thus suggest the need for further studies towards improving the quantitative prediction of aerosol transport and deposition in the human airways.

3D fabrication of complex copper microstructures with path planning by localized electrochemical deposition

3D fabrication of complex copper microstructures with path planning by localized electrochemical deposition

Thin-film flow due to an asymmetric distribution of surface tension and applications to surfactant deposition

Thin-film equations are utilised in many different areas of fluid dynamics when there exists a direction in which the aspect ratio can be considered small. We consider thin free films with Marangoni effects in the extensional flow regime, where velocity gradients occur predominantly along the film. In practice, because of the local deposition of surfactants or input of energy, asymmetric distributions of surfactants or surface tension more generally, are possible. Such examples include the surface of bubbles and the rupture of thin films. In this study, we consider the asymmetric thin-film equations for extensional flow with Marangoni effects. Concentrating on the case of small Reynolds number $ Re $ , we study the deposition of insoluble surfactants on one side of a liquid sheet otherwise at rest and the resulting thinning and rupture of the sheet. The analogous problem with a uniformly thinning liquid sheet is also considered. In addition, the centreline deformation is discussed. In particular, we show analytically that if the surface tension isotherm $\sigma = \sigma (\varGamma )$ is nonlinear (surface tension $\sigma$ varies with surfactant concentration $\varGamma$ ), then accounting for top–bottom asymmetry leads to slower (faster) thinning and pinching if $\sigma = \sigma (\varGamma )$ is convex (concave). The analytical progress reported in this paper allows us to discuss the production of satellite drops from rupture via Marangoni effects, which, if relevant to surface bubbles, would be an aerosol production mechanism that is distinct from jet drops and film drops.

Phase-Field Modeling of Electrolyte Transport Properties and Elasticity Modulus in Suppression of Dendrite Growth in Solid-State-Lithium-Ion-Batteries

Dendrite formation in batteries is a critical issue that affects battery performance and lifespan. Solid-state electrolytes have gained attention due to their advantages such as compactness, higher energy density, and enhanced safety. This study investigates dendrite growth in batteries via phase field simulations utilizing a grand potential-based phase field model. The simulations are executed using the MOOSE (Multiphysics Object-Oriented Simulation Environment) framework, a Finite Element Method (FEM) based solver known for its modular approach and proficiency in handling complex multi-physics problems. Initially, the study considers a pure lithium anode and a 1M LiPF6 electrolyte for the liquid case. To explore the benefits of solid electrolytes, a fictitious solid electrolyte with transport properties similar to the liquid electrolyte but having different mechanical properties is considered. The mechanical impact resulting from the volume changes due to lithium deposition is not accounted for in the liquid electrolyte model. However, the solid electrolyte model addresses this by modifying the Butler-Volmer kinetics and incorporating the influence of stresses on the localized lithium deposition. Sensitivity analysis is performed for various parameters in both the liquid and solid electrolytes. The results indicate that dendrite growth is reduced with decreased applied over-potential and interfacial energies. For solid electrolytes, an additional parameter, increased Young’s modulus, contributes to reduced dendrite growth. The evaluation of dendrite growth involves quantifying surface roughness using the root mean square (RMS) approach. The elasticity modulus significantly influences dendrite formation, with higher values in materials like LLZO, and glass Li3PS4 exhibiting lower dendrite growth, while lower values in polymer-based materials like P(VDF-HFP) and PVDF/CAB/PE exhibit higher dendrite growth. The solid electrolyte acts as a crucial mechanical barrier, influencing the dendrite tip growth rate and ensuring uniform electrodeposition throughout the dendritic structure. Furthermore, the work investigates the impact of the cathode on dendrite growth. The contraction of the cathode provides additional space for dendrites to move, leading to reduced compressive stresses and increased dendrite growth. Conversely, higher compressive stresses suppress dendrite growth.

Dosimetric implications of kidney anatomical volume changes in 177Lu-DOTATATE therapy

IntroductionThis study aims to evaluate the use of CT-based whole kidney parenchyma (WKP) segmentation in 177Lu-DOTATATE dosimetry. Specifically, it investigates whether WKP volumes change during treatment and evaluates the accuracy of applying a single delineated WKP volume for dosimetry. Furthermore, it aims to determine the cause of WKP volume changes—whether caused by radiation or amino acid infusion—by comparing them with spleen volume changes as a marker for radiation-induced alterations.MethodsSPECT/CT images of 18 patients were acquired over the abdomen approximately 4 h (h) (D0), 24 h (D1), 48 h (D2) and 168 h (D7) post-administration of 177Lu-DOTATATE. CT guided WKP volumes were measured before (baseline) and during treatment. Kidney activity concentrations at each time point were derived from CT-segmented WKP overlaid on SPECT scans. The accuracy of using WKP segmentation from a single CT for all time points was assessed against the gold standard of segmenting each WKP individually. Time-integrated activity calculations were based on a tri-exponential curve fit of the kidney activity concentration over time. Kidney absorbed doses were estimated under the assumption of local energy deposition. Additionally, the impact of various partial volume correction methods on dosimetry was evaluated.ResultsWhole-kidney parenchyma (WKP) volumes, ranging from 31 to 243 mL, showed a gradual increase from baseline (mean ± SD = 130.6 ± 46.1 mL) at the initial time points D0 (138.5 ± 44.7 mL) and D1 (139.4 ± 41.6 mL), followed by a slight decrease at D2 (132.8 ± 44.5 mL) and a further decrease at D7 (129.2 ± 42.7 mL). The volume increase at D0 and D1 was statistically significant. Spleen volume did not change during treatment, suggesting that amino acid infusion rather than irradiation effects caused WKP volume changes. Bland-Altman analysis revealed WKP volume biases of 8.77% (D0 vs. BL), 10.77% (D1 vs. BL), 1.10% (D2 vs. BL), and 1.10% (D7 vs. BL), with corresponding uncertainties of 24.4%, 23.6%, 25.4%, and 25.4%, respectively. When WKP segmentation from a single CT is applied across all SPECTs, these WKP volume changes could overestimate the activity concentration and mean absorbed doses up to 4.3% and 2.5%, respectively. The absorbed dose uncertainties using a recovery coefficient (RC) of 0.85 for single-time-point WKP delineation increase the absorbed dose uncertainty by 4% compared to the use of patient-specific RCs and time specific segmentation of WKP volumes.ConclusionsKidney volume exhibited significant variation form D0 to D7, affecting the precision of dosimetry calculation, primarily due to errors in whole-kidney parenchyma (WKP) delineation. Notably, using WKP segmentation from a single CT scan applied to sequential SPECT images introduce further uncertainty and may lead to an overestimation of the absorbed dose. The fluctuations in kidney volume are most likely attributable to amino acid infusion.

Translating contrast enhanced computed tomography images to liver radioembolization dose distribution for more comprehensively indicating patients

Objective. Contrast-enhanced computed tomography (CECT) is commonly used in the pre-treatment evaluation of liver Y-90 radioembolization feasibility. CECT provides detailed imaging of the liver and surrounding structures, allowing healthcare providers to assess the size, location, and characteristics of liver tumors prior to the treatment. Here we propose a method for translating CECT images to an expected dose distribution for tumor(s) and normal liver tissue. Approach. A pre-procedure CECT is used to obtain an iodine arterial-phase distribution by subtracting the non-contrast CT from the late arterial phase. The liver segments surrounding the targeted tumor are selected using Couinaud’s method. The resolution of the resulting images is then degraded to match the resolution of the positron emission tomography (PET) images, which can image the Y-90 activity distribution post-treatment. The resulting images are then used in the same way as PET images to compute doses using the local deposition method. CECT images from three patients were used to test this method retrospectively and were compared with Y-90 PET-based dose distributions through dose volume histograms. Main results. Results show a concordance between predicted and delivered Y-90 dose distributions with less than 10% difference in terms of mean dose, for doses greater than 10% of the 98th percentile (D2%). Significance. CECT-derived predictions of Y-90 radioembolization dose distributions seem promising as a supplementary tool for physicians when assessing treatment feasibility. This dosimetry prediction method could provide a more comprehensive pre-treatment evaluation—offering greater insights than a basic assessment of tumor opacification on CT images.

Improving rate performance of FeC2O4/rGO composites on lithium storage via single-polymerization‐induced electrostatic self‐assembly

Based on the wide interlayer distance for ions diffusion, iron (II) oxalate exhibits excellent lithium storage ability. However, the local deposition of metallic nanoparticles of Fe0 leads to low electrochemical reactivity, which hinders the actual application of FeC2O4 in large current regions (>5C). To solve this problem, a strong cationic polymeric electrolyte, polyelectrolyte diallyl dimethyl ammonium (PDDA), was introduced to construct a [FeC2O4(PDDA)]+ ligand. By single-polymerization‐induced electrostatic self-assembly, the [FeC2O4(PDDA)]+ ligand was combined with the surface-charged rGO to produce a FeC2O4/rGO material. It is proved that the rGO carrier improves the interparticle conductivity, electrochemical activity and structure stability of the iron (II) oxalate particles, ensuring the stability of Li || FeC2O4/rGO battery at a rapid charging rate of 20C (8 A g−1) for more than 500 cycles (with the special capacity of 713 mAh g−1). Compared with FeC2O4 electrode, owning to high reactivity of rGO and continuously activating on the nanoscale Fe metal generated at ∼0.75 V, FeC2O4/rGO shows higher electrochemical activity of conversion reaction in the first 50 cycles and better reversibility in the rate charge–discharge test (the capacity rapidly increased to 1158.8 mAh g−1 after 20C cycles). This work reveals how the structural design of conducting and supporting the carrier can achieve fast charging for iron (II) oxalate lithium-ion batteries.

Desmoid tumors of rectus abdominis: A case report and literature review.

Desmoid tumor (DT) is a rare soft tissue tumor that can occur anywhere in the body. Abdominal wall DT presents unique clinical challenges due to its distinctive manifestations, treatment modalities, and the lack of biomarkers for diagnosis and recurrence prediction, making clinical decisions exceedingly complex. A 32-year-old female who underwent radical resection combined with patch reinforcement for rectus abdominis DT, successfully alleviating abdominal discomfort, with no recurrence during the 6-month follow-up after surgery. Based on the imaging studies and medical history, the patient underwent radical surgical resection. Histopathology reveals that the tumor cells predominantly composed of proliferative fibroblasts with local collagen deposition. The lesional cells show positive staining for β-catenin, indicating a diagnosis of DT. The patient underwent radical surgical resection with patch reinforcement to repair the abdominal wall defect. Pathology confirmed negative margins, achieving an R0 resection, and genetic testing identified a T41A mutation in CTNNB1. Consequently, no additional adjuvant therapy was administered postoperatively. The patient was discharged with the incision healing well after 3 days postoperation. Upon reexamination 6 months later, no recurrence or adverse complications were observed. Abdominal wall DT treatment requires personalized plans from multidisciplinary team discussions. Genetic testing plays a crucial role in identifying novel biomarkers for abdominal wall DT. We have once again demonstrated the significant clinical significance of CTNNB1 mutations in the diagnosis and progression of abdominal wall DT. Additionally, genes such as CCND1, CYP3A4, SLIT1, RRM1, STIM1, ESR2, UGT1A1, among others, may also be closely associated with the progression of abdominal wall DT. Future research should delve deeper into and systematically evaluate the precise impact of these genetic mutations on treatment selection and prognosis for abdominal wall DT, in order to better guide patient management and treatment decisions.

Nitric oxide-based treatments improve wound healing associated with diabetes mellitus.

Non-healing wounds are long-term complications of diabetes mellitus (DM) that increase mortality risk and amputation-related disability and decrease the quality of life. Nitric oxide (NO·)-based treatments (i.e., use of both systemic and topical NO· donors, NO· precursors, and NO· inducers) have received more attention as complementary approaches in treatments of DM wounds. Here, we aimed to highlight the potential benefits of NO·-based treatments on DM wounds through a literature review of experimental and clinical evidence. Various topical NO·-based treatments have been used. In rodents, topical NO·-based therapy facilitates wound healing, manifested as an increased healing rate and a decreased half-closure time. The wound healing effect of NO·-based treatments is attributed to increasing local blood flow, angiogenesis induction, collagen synthesis and deposition, re-epithelization, anti-inflammatory and anti-oxidative properties, and potent broad-spectrum antibacterial effects. The existing literature lacks human clinical evidence on the safety and efficacy of NO·-based treatments for DM wounds. Translating experimental favors of NO·-based treatments of DM wounds into human clinical practice needs conducting clinical trials with well-predefined effect sizes, i.e., wound reduction area, rate of wound healing, and hospital length of stay.

Strain in Hybrid Organic-Inorganic Metal Halide Perovskites Microstructures by Numerical Simulations.

Hybrid organic-inorganic metal halide perovskites (HOIPs) are promising materials for optoelectronics applications. Their optical and electrical properties can be controlled by strain engineering, that results from application of local elastic deformation or deposition on pre-patterned substrates acquiring a conformal 3D shape. Most interesting, their mechanical properties depend on their crystal structure, composition and dimensionality. We explore by numerical simulations the deformation of a selection of HOIPs comprising a broad range of elastic properties. We consider an axial symmetry with the formation of microdomes on flakes. Radial and vertical forces are considered, finding that the radial force is more effective to obtain large deformation. Large vertical displacement and strain is obtained for HOIPs with low stiffness. The layered nature of HOIPs, that are formed by inorganic layers of different thickness and organic spacers, is also investigated, revealing a non-monotonous trend with the proportion of inorganic to organic part.

Bone density in postmenopausal women with scoliosis is associated with markers of degenerative joint disease.

Bone mineral density (BMD) measured with dual x-ray absorptiometry (DXA) is the clinical standard for the diagnosis of osteoporosis and prediction of bone fracture risk. In the aging skeleton, osteoporosis is often concomitantly present with degenerative joint disease (DJD). In this study, we evaluated tissue-level changes in the differentially loaded concave (CC) and convex (CV) sides of the lumbar spine in a sample of postmenopausal women with scoliosis. We used a cumulative degeneration score to assess osteophyte formation, the severity of sclerotic morphology, and marrow changes as markers of DJD in the lumbar spine and examined the correlation between markers of DJD and BMD. More severe osteophyte growth and sclerosis were present on the CC side of the spine. The degenerative score (DS) was higher on the CC side of the lumbar spine compared with the CV side. While CC BMD was positively correlated with CC DS and marrow, CV DS was not correlated with CV BMD. Marrow changes were correlated with DS on the CC lumbar spine. These results highlight the importance of mechanoadaptive as well as broader inflammatory processes in the manifestation of degenerative changes and local mineral deposition at the lumbar spine. DXA-based BMD measurement of osteoporosis need to be contextualized within the biomechanical and degenerative conditions of a joint rather than using a strict threshold cutoff.

Effect of dynamic exclusion and the use of FAIMS, DIA and MALDI-mass spectrometry imaging with ion mobility on amyloid protein identification

Amyloidosis is a disease characterized by local and systemic extracellular deposition of amyloid protein fibrils where its excessive accumulation in tissues and resistance to degradation can lead to organ failure. Diagnosis is challenging because of approximately 36 different amyloid protein subtypes. Imaging methods like immunohistochemistry and the use of Congo red staining of amyloid proteins for laser capture microdissection combined with liquid chromatography tandem mass spectrometry (LMD/LC–MS/MS) are two diagnostic methods currently used depending on the expertise of the pathology laboratory. Here, we demonstrate a streamlined in situ amyloid peptide spatial mapping by Matrix Assisted Laser Desorption Ionization–Mass Spectrometry Imaging (MALDI-MSI) combined with Trapped Ion Mobility Spectrometry for potential transthyretin (ATTR) amyloidosis subtyping. While we utilized the standard LMD/LC–MS/MS workflow for amyloid subtyping of 31 specimens from different organs, we also evaluated the potential introduction in the MS workflow variations in data acquisition parameters like dynamic exclusion, or testing Data Dependent Acquisition combined with High-Field Asymmetric Waveform Ion Mobility Spectrometry (DDA FAIMS) versus Data Independent Acquisition (DIA) for enhanced amyloid protein identification at shorter acquisition times. We also demonstrate the use of Mascot’s Error Tolerant Search and PEAKS de novo sequencing for the sequence variant analysis of amyloidosis specimens.

An International Study of Factors Affecting Variability of Dosimetry Calculations, Part 3: Contribution from Calculating Absorbed Dose from Time-Integrated Activity.

Image-based dosimetry-guided radiopharmaceutical therapy has the potential to personalize treatment by limiting toxicity to organs at risk and maximizing the therapeutic effect. The 177Lu dosimetry challenge of the Society of Nuclear Medicine and Molecular Imaging consisted of 5 tasks assessing the variability in the dosimetry workflow. The fifth task investigated the variability associated with the last step, dose conversion, of the dosimetry workflow on which this study is based. Methods: Reference variability was assessed by 2 medical physicists using different software, methods, and all possible combinations of input segmentation formats and time points as provided in the challenge. General descriptive statistics for absorbed dose values from the global submissions from participants were calculated, and variability was measured using the quartile coefficient of dispersion. Results: For the liver, which included lesions with high uptake, variabilities of up to 36% were found. The baseline analysis showed a variability of 29% in absorbed dose results for the liver from datasets where lesions included and excluded were grouped, indicating that variation in how lesions in normal liver were treated was a significant source of variability. For other organs and lesions, variability was within 7%, independently of software used except for the local deposition method. Conclusion: The choice of dosimetry method or software had a small contribution to the overall variability of dose estimates.