Global Estimates Research Articles

Climate-Induced Saltwater Intrusion in 2100: Recharge-Driven Severity, Sea Level-Driven Prevalence.

Saltwater intrusion is a critical concern for coastal communities due to its impacts on fresh ecosystems and civil infrastructure. Declining recharge and rising sea level are the two dominant drivers of saltwater intrusion along the land-ocean continuum, but there are currently no global estimates of future saltwater intrusion that synthesize these two spatially variable processes. Here, for the first time, we provide a novel assessment of global saltwater intrusion risk by integrating future recharge and sea level rise while considering the unique geology and topography of coastal regions. We show that nearly 77% of global coastal areas below 60° north will undergo saltwater intrusion by 2100, with different dominant drivers. Climate-driven changes in subsurface water replenishment (recharge) is responsible for the high-magnitude cases of saltwater intrusion, whereas sea level rise and coastline migration are responsible for the global pervasiveness of saltwater intrusion and have a greater effect on low-lying areas.

A new global carbon flux estimation methodology by assimilation of both in situ and satellite CO2 observations

Accurate estimation of carbon removal by terrestrial ecosystems and oceans is crucial to the success of global carbon mitigation initiatives. The emergence of multi-source CO2 observations offers prospects for an improved assessment of carbon fluxes. However, the utility of these diverse observations has been limited by their heterogeneity, leading to much variation in estimated carbon fluxes. To harvest the diverse data types, this paper develops a multi-observation carbon assimilation system (MCAS), which simultaneously integrates both satellite and ground-based observations. MCAS modifies the ensemble Kalman filter to apply different inflation factors to different types of observation errors, addressing the heterogeneity between satellite and in situ data. In commonly used independent validation datasets, the carbon flux derived from MCAS outperformed those obtained from a single source, demonstrating a 20% reduction in error compared to existing carbon flux products. We use MCAS to conduct ecosystem and ocean carbon flux inversion for the period of 2016–2020, which reveals that the 5-year average global net terrestrial and ocean sink was 1.84 ± 0.60 and 2.74 ± 0.49 petagrams, absorbing approximately 47% of human-caused CO2 emissions together, which were consistent with the global carbon project estimates of 1.82 and 2.66 petagrams. All these facts suggest MCAS is a better methodology than those for assimilating single-source observation only.

Different and unusual presentation of Gaucher’s disease with the same mutation in the glucocerebrosidase enzyme (F266L) in two patients: a case report

BackgroundGaucher is an autosomal recessive inherited lysosomal storage disorder. The incidence of this disease is rare with a global estimate of around 1 in 57,000 to 1 in 75,000. Gaucher’s disease is caused by a mutation in the glucocerebrosidase gene. Common symptoms of this disease include hepatosplenomegaly, moderate neurological symptoms, and late‑onset skeletal alterations. However, Gaucher can sometimes have rare presentations that lead to a delayed diagnosis in patients. This report discusses two adult cases of Gaucher’s disease (type 1) with the same mutation but with unusual symptoms.Case presentationOne patient was a 44-year-old man who had been experiencing chronic cough since he was 10 years old, and the other patient was a 27-year-old woman with itching, both atypical symptoms of Gaucher. Bronchodilators and prednisolone were administered for chronic cough and antihistamines and prednisolone were given for the itching, but little to no improvement was seen. Sonography tests revealed that both cases had splenomegaly, hepatomegaly, and liver malfunction, characteristic of Gaucher’s disease. Bone marrow aspiration tests confirmed the presence of Gaucher’s cells in their bones. The level of glucocerebrosidase enzyme in both cases was less than 1.5 nmol/mL/hour. Whole exon sequencing confirmed a mutation on exon 8 of the GBA1 gene in a homozygous form in both cases, resulting in a transversion mutation (C > G) at position c.798, leading to the substitution of phenylalanine 266 with leucine. Both patients were of Bakhtiyari ethnicity and had parents who were in a consanguineous marriage. After receiving Cerezyme treatment, both cases experienced a disappearance of their cough and itching symptoms.ConclusionThis report highlights the importance of recognizing the unusual presentation of Gaucher’s disease especially in regions with high rates of consanguineous marriage and thalassemia. This knowledge can aid physicians in making accurate diagnoses and providing appropriate treatment.

Global patterns of leukemia by subtype, age, and sex in 185 countries in 2022.

In 2022, leukemia ranked as the second most common hematological malignancy after non-Hodgkin lymphoma worldwide. However, updated global estimates of leukemia incidence by subtype are unavailable. We estimated leukemia incidences for different leukemia subtypes by country, world region, and human developmental index using data from the Cancer Incidence in Five Continents databases combined with the GLOBOCAN 2022 estimates of leukemia in 185 countries. We estimated sex-specific age-standardized rates (ASRs) per 100 000 for children (0-19 years) and adults (20+ years). In adults, the most common leukemia worldwide was AML (males:38%, ASR = 3·1; females:43%, ASR = 2·4), followed by CLL (males:28%, ASR = 2·2; females:24%, ASR = 1·3). In very high HDI countries, the ASR of CLL was higher than the ASR of AML among males (5·2 versus 4·3, respectively) and similar among females (2·9 and 3·0, respectively). In children, the most common leukemia was ALL (boys:70%, ASR = 2·4; girls:68%, ASR = 1·8) followed by AML (boys:22%, ASR = 0·76; girls:25%, ASR = 0·65). ALL proportions varied across world sub-regions from 57to78% among boys, and from 49 to 80% among girls. Our findings suggest clear geographical patterns of leukemia subtypes in adults and children. Further research into underlying causes that explain these variations is needed to support cancer control strategies for prevention and plan national healthcare needs.

GANzzle[formula omitted]: Generative approaches for jigsaw puzzle solving as local to global assignment in latent spatial representations

Jigsaw puzzles are a popular and enjoyable pastime that humans can easily solve, even with many pieces. However, solving a jigsaw is a combinatorial problem, and the space of possible solutions is exponential in the number of pieces, intractable for pairwise solutions. In contrast to the classical pairwise local matching of pieces based on edge heuristics, we estimate an approximate solution image, i.e., a mental image, of the puzzle and exploit it to guide the placement of pieces as a piece-to-global assignment problem. Therefore, from unordered pieces, we consider conditioned generation approaches, including Generative Adversarial Networks (GAN) models, Slot Attention (SA) and Vision Transformers (ViT), to recover the solution image. Given the generated solution representation, we cast the jigsaw solving as a 1-to-1 assignment matching problem using Hungarian attention, which places pieces in corresponding positions in the global solution estimate. Results show that the newly proposed GANzzle-SA and GANzzle-VIT benefit from the early fusion strategy where pieces are jointly compressed and gathered for global structure recovery. A single deep learning model generalizes to puzzles of different sizes and improves the performances by a large margin. Evaluated on PuzzleCelebA and PuzzleWikiArts, our approaches bridge the gap of deep learning strategies with respect to optimization-based classic puzzle solvers.

X-BASE: the first terrestrial carbon and water flux products from an extended data-driven scaling framework, FLUXCOM-X

Abstract. Mapping in situ eddy covariance measurements of terrestrial land–atmosphere fluxes to the globe is a key method for diagnosing the Earth system from a data-driven perspective. We describe the first global products (called X-BASE) from a newly implemented upscaling framework, FLUXCOM-X, representing an advancement from the previous generation of FLUXCOM products in terms of flexibility and technical capabilities. The X-BASE products are comprised of estimates of CO2 net ecosystem exchange (NEE), gross primary productivity (GPP), evapotranspiration (ET), and for the first time a novel, fully data-driven global transpiration product (ETT), at high spatial (0.05°) and temporal (hourly) resolution. X-BASE estimates the global NEE at −5.75 ± 0.33 Pg C yr−1 for the period 2001–2020, showing a much higher consistency with independent atmospheric carbon cycle constraints compared to the previous versions of FLUXCOM. The improvement of global NEE was likely only possible thanks to the international effort to increase the precision and consistency of eddy covariance collection and processing pipelines, as well as to the extension of the measurements to more site years resulting in a wider coverage of bioclimatic conditions. However, X-BASE global net ecosystem exchange shows a very low interannual variability, which is common to state-of-the-art data-driven flux products and remains a scientific challenge. With 125 ± 2.1 Pg C yr−1 for the same period, X-BASE GPP is slightly higher than previous FLUXCOM estimates, mostly in temperate and boreal areas. X-BASE evapotranspiration amounts to 74.7×103 ± 0.9×103 km3 globally for the years 2001–2020 but exceeds precipitation in many dry areas, likely indicating overestimation in these regions. On average 57 % of evapotranspiration is estimated to be transpiration, in good agreement with isotope-based approaches, but higher than estimates from many land surface models. Despite considerable improvements to the previous upscaling products, many further opportunities for development exist. Pathways of exploration include methodological choices in the selection and processing of eddy covariance and satellite observations, their ingestion into the framework, and the configuration of machine learning methods. For this, the new FLUXCOM-X framework was specifically designed to have the necessary flexibility to experiment, diagnose, and converge to more accurate global flux estimates.

Superconvergence analysis and extrapolation of a BDF2 fully discrete scheme for nonlinear reaction–diffusion equations

The main aim of this paper is to propose a 2-step backward differential formula (BDF2) fully discrete scheme with the bilinear Q11 finite element method (FEM) for the nonlinear reaction–diffusion equation. By use of the combination technique of the element’s interpolation and Ritz projection, and through the interpolation post-processing approach, the superclose and global superconvergence estimates with order O(h2+τ2) in H1-norm are deduced rigorously. Furthermore, with the help of the asymptotic error expansion of the Q11 element, a new suitable fully discrete scheme is developed, and the extrapolation result of order O(h3+τ2) in H1-norm is derived, which is one order higher than that of the above traditional superconvergence estimate with respect to h. Here h is the mesh size and τ is the time step. Finally, some numerical results are provided to verify the theoretical analysis. It seems that the extrapolation of the fully discrete finite element scheme has never been seen in the previous studies.

Fractional pseudo-parabolic equation with memory term and logarithmic nonlinearity: Well-posedness, blow up and asymptotic stability

Considered herein is the initial–boundary value problem for a fractional pseudo-parabolic equation with memory term and logarithmic nonlinearity given by ut+(−Δ)su+(−Δ)sut=∫0tg(t−τ)(−Δ)su(τ)dτ+uln|u| under different initial energy levels. The local well-posedness of weak solution is firstly established by using Galerkin approximation and contraction mapping principle at arbitrary initial energy level. Secondly, the global well-posedness, polynomial and exponential energy decay estimates, finite time blow up are investigated at low initial energy level (u0∈Wδ,1) by utilizing modified potential well theory, Galerkin approximation, perturbed energy method, differential–integral inequality technique etc. Subsequently, based on the above conclusions of low initial energy, the global existence, polynomial and exponential energy decay estimates and finite time blow up are also derived at critical initial energy level (u0∈Wδ,2) by introducing some new approximation methods and techniques. Here, the sets Wδ,i(i=1,2) defined in Section 2.2 denote potential well families involving the parameter δ>0. Finally, we give a series of numerical examples used to illuminate above theoretical results.

Population size and structure of Grant's gazelle and lesser kudu in Geralle National Park, Southeastern Ethiopia.

Grant's gazelle and lesser kudu remain widespread within and outside protected areas. Current pressures on their populations, human encroachment and disturbance associated habitat modifications, and excessive grazing pose further threats to the species. The estimation of density and abundance of species has significant value for sustainable wildlife management in Geralle National Park (GNP) and also contributes towards a more accurate global population estimate. Using distance sampling methods, the lowest Akaike Information Criterion (AIC) (close to zero) and Chi-square tests (P value >0.05) showed that the hazard rate key function with an un-equal interval group model was selected for estimation of density and abundance. The density of species was 1.7±0.5, 2.07±0.7, gazelle/km2 and 1.39±0.3, 1.92±0.42, lesser kudu/km2 during the dry and wet seasons, respectively. Population density, abundance, and structure showed habitat and seasonal differences in observation. More individuals of both species were recorded during the wet season as compared to the dry season. Grassland was favored by Grant's gazelle, while lesser kudu preferred woodlands. Both species exhibited a female-biased sex ratio, indicating potential for future population growth prospects. It can be concluded that GNP is home to viable populations of Grant's gazelle and lesser kudu, and season has influenced population abundance and distribution due to resource availability variations among seasons. The female-biased sex ratio indicates the future population growth prospects for the two species.

Icelandic glacial dissolved organic carbon fluxes, composition and variability - relevance for the global glacial carbon budget

Despite their relatively large size, Icelandic glaciers, and their organic carbon (OC) fluxes, have not been explicitly considered in current global glacial OC flux calculations. Most global glacial OC estimates are based on limited individual flux estimates, often determined during the melt season, rarely accounting for the seasonal and diurnal variability of glacial dissolved organic matter (DOM). Using an annual dataset of 25 Icelandic glaciers (and their glacial streams) we investigate DOM concentration and composition, calculating an estimate for downstream OC fluxes from Icelandic glaciers, considering diurnal and seasonal variability. DOM source and composition distinctly changed from a terrestrial character toward a more proteinaceous character as melt increased, both on a seasonal and diurnal basis, likely reflecting the flow path of the meltwater. While DOC concentration did not change on a diurnal basis, DOM composition was more labile in the afternoons, possibly indicating photochemical or biological transformation processes. Overall, the glacial streams predominantly acted as CO2 sinks. However, higher DOC concentrations, along with contributions of more proteinaceous DOM in proglacial streams, led to a decrease in the uptake potential for CO2. Finally, we estimated an export flux of 0.0026 ± 0.0029 Gg C yr−1 km−2 of DOC, and 0.011 ± 0.007 Tg C yr−1 km−2 of POC, from Icelandic glaciers. We reveal larger than previously assumed DOC and POC fluxes from Icelandic glaciers, with higher-than-global-average areal fluxes (~3 % and 9 % of global glacial C flux respectively). Our findings underscore the importance of revising current global estimates to include the not-fully-accounted-for contribution of Icelandic, and other glaciers. This is particularly important considering ongoing climatic changes will likely affect glacial meltwater discharge and sources, leading to altered DOM composition and DOC concentration, having potentially considerable consequences for glacial OC export and CO2 uptake potentials of glacial streams.

Worldwide Burden of Retinoblastoma from 1990 to 2021

Introduction: The aim of the study was to report the global, regional, and national burden of retinoblastoma between 1990 and 2021, by age, sex, and sociodemographic index (SDI). Methods: We leveraged the Global Burden of Disease 2021 Study to elucidate the epidemiological landscape of retinoblastoma, encompassing prevalence, incidence, mortality, and disability-adjusted life years (DALYs) across 204 nations and territories spanning the period from 1990 to 2021. The SDI was employed to evaluate the interplay between socioeconomic development and the burden of retinoblastoma. Results: In 2021, global estimates unveiled 57,333 prevalent cases of retinoblastoma, yielding 6,274 incident cases, 2,762 deaths, and 243,204 DALYs. Globally, the age-standardized prevalence, incidence, mortality, and DALY rates for retinoblastoma in 2021 were 0.86, 0.09, 0.04, and 3.65 per 100,000 population, respectively. Tokelau, Kenya, and Portugal demonstrated the highest age-standardized prevalence and incidence rates of retinoblastoma in 2021. The global prevalence of retinoblastoma peaks among children aged 2–4 years and subsequently declines with increasing age. At the regional level, the correlation between SDI and age-standardized prevalence rates for retinoblastoma manifested a V-shaped pattern. Conclusions: This comprehensive examination of retinoblastoma epidemiological trends underscores the imperative for heightened vigilance and more efficacious therapeutic interventions, especially within resource-limited environments. The findings accentuate the need for targeted strategies to address the disparate burden of retinoblastoma across diverse socioeconomic landscapes.

Abstract 4124675: Deep Learning Screening of Cardiac MRIs Uncovers Undiagnosed Hypertrophic Cardiomyopathy in the UK BioBank

Introduction: The prevalence of hypertrophic cardiomyopathy (HCM) in the UK Biobank based on ICD-10 codes (.07%) is lower than global estimates of disease prevalence (0.2 - 0.5%). Prior studies using this data have remarked on the limitations of findings given likely underdiagnosis. The availability of cardiac MRI scans on a fraction of the participants offers an opportunity to identify missed diagnoses. Aims: This study seeks to utilize a generalizable deep learning model to detect likely cases of undiagnosed hypertrophic cardiomyopathy from cardiac MRIs in the UK Biobank. Methods: The foundational model was trained on a multi-institutional dataset of 14,073 cardiac MRIs via a self-supervised contrastive learning approach that sought to minimize the divergence between scans and their associated radiology reports. The pre-trained model was fine-tuned to diagnose hypertrophic cardiomyopathy on a distinct cohort of 4,870 MRIs with 368 cases of HCM, achieving an AUC of 0.94. The fine-tuned model was applied to the UK Biobank cardiac MRI dataset to ascertain predicted probabilities of HCM. Cases exceeding a threshold of 95% – correlating to the top 0.5% of cases (expected specificity of 97% and sensitivity of 60%) – were screened in for manual reading. In a blinded fashion, a board-certified radiologist was tasked with diagnosing HCM on a sample of cases composed of high and low predicted probabilities. Results: Of the 43,017 patients with cardiac MRIs, only 9 (.02%) had an ICD diagnosis of HCM. 266 cardiac MRIs were manually reviewed: 216 had greater than 95% predicted probability of HCM; 50 negative controls were randomly selected amongst cases with predicted probability less than 10%. The radiologist concurred with an HCM diagnosis for 115 cases (sensitivity 53%, specificity 98%), 112 of which were previously undiagnosed. The prevalence of hypertension and aortic stenosis did not significantly differ between the cohort of true positives (69.2%) and false positives (76.6%). The corrected prevalence of HCM in the UK BioBank MRI cohort is estimated at 0.28%. Conclusions: The findings of this study illustrate the remarkable ability of a generalizable deep learning model to detect undiagnosed cases of a rare disease process from cardiac MRIs. This is an important milestone that may allow for widespread screening of hypertrophic cardiomyopathy while minimizing demand for radiologist labor, and thereby allow patients to reap the substantial benefits of earlier treatment.

Global well-posedness and exponential decay estimates for semilinear Newell–Whitehead–Segel equation

Abstract This article presents the application of the Faedo–Galerkin compactness method to establish the local well-posedness of the Newell–Whitehead–Segel equation. By analyzing a finite-dimensional approximate problem, the existence and uniqueness of a local solution were demonstrated. A priori estimates were derived, enabling the transition to the limit and the recovery of the original problem’s local solution. The study further proves the uniqueness and continuous dependence of the solution on initial data. Additionally, under certain conditions, it is shown that the energy norm of the solution decays exponentially over time, and the L 2 {L}^{2} -norm of the time derivative of the solution approaches zero asymptotically.

Contraceptive Change and Fertility Transition

AbstractOver the past half‐century, most countries have made progress through their demographic transitions with continuing declines in mortality and fertility. The major driver of fertility decline has been the adoption of contraception by women of reproductive age who increasingly desire smaller families. This paper documents the massive changes in contraceptive behavior that have occurred since 1970 at the global and regional levels and examines contraceptive use differentials by marital status and method. To understand the proximate causes of the rise in contraceptive use, we document the changes in the potential demand for contraception (among women who want to space or limit their childbearing) and the degree to which this potential demand is satisfied by the actual practice of contraception. The paper concludes with a confirmation of the strong inverse relationship between contraceptive use and fertility. The main sources of data for these analyses are comprehensive datasets with country, regional, and global estimates of historical trends in fertility and contraceptive behavior maintained by the Population Division of the United Nations.

CARBON CAPTURE, USAGE AND STORAGE

Carbon Capture, Usage and Storage – in short CCUS, is not a new term in the current industrial environment. It is being discussed widely at all industrial forums, across all countries, big or small, to control pollution to ensure a healthy and happy life for all. There have been attempts and studies over last 50 years to capture carbon dioxide from the environment to avoid pollution and control global warming scenario. Many technologies have been in use for carbon capture, across the globe, some in large scale and others confined to local areas. It is expensive but very much essential – it is a goal set by WHO/UNO/European Commission – to clean the environment off CO2 gases, use it for alternative purposes or store it for future action. According to International Energy Agency (IEA), we must capture around 100 billion tons of CO2 by 2060 to meet International Global Warming and Energy goals. It is a huge goal and is a very expensive goal to achieve. All big countries who impact the environment in a huge way through their industries shall come forward for a collaboration to prepare a robust plan, pump-in money, monitor and control the processes, to achieve the goal. There is an estimate that US emitted around 5,1 mln t of CO2 in 2019 whereas Global estimate emitted around 33 mln t. These are very huge numbers and hence Global monitoring is very essential to control emission and safe storage and disposal. It is important to understand that Carbon Capture (CC), Carbon Capture and Use (CCU) and Carbon Capture and Storage (CCS) are three different terms. CC, CCU and CCS are combinedly termed as CCUS. CC is to capture carbon from various sources – fuel gas, fossil fuels, petroleum products, flares from refineries and power plants etc. Usage of the captured carbon in the form of carbon dioxide (CO2) is CCU and this is an important long-term vision by any government to ensure it is being used meaningful to avoid negative impact on climate. CCS is storage of the captured carbon quickly so that it does not impact the environment as a greenhouse gas and at the same time, it can be used later. Another term which is frequently used is Net Zero CO2. It is defined as follows: Any CO2 released into the atmosphere from a human activity shall be balanced by an equivalent amount being removed, either by nature-based solutions (including afforestation, reforestation or other changes in land use) or technological solutions that stores CO2 captured directly or indirectly, permanently. Net Zero CO2 is very important, unless this is achieved, CCUS goal cannot be achieved to control climate change. This write-up provides an insight into the following topics:  What is CCUS?  Why is it important?  Steps to CCUS;  CAPEX and OPEX involved.

Recuperation mechanism of direct taxation to control post covid economic contraction: India’s new tax reform with crypto tax

This study explores the impact of the progressive tax structure on income equality, emphasizing the significance of direct taxes in promoting economic and social equality. It also examines the challenges faced by the Indian government in meeting its revenue targets due to the decline in corporation tax and personal income tax revenues. The present study assesses the role of the newly implemented tax by the Indian Finance Ministry on capital gains from the sale or purchase of cryptocurrencies and its impact on economic growth. A qualitative approach has been adopted, utilizing secondary information sources for characterization and analysis. The study relies on Time Series Data from the Income Tax Department for the financial years 2000-01 to 2018-19 and global estimates of total tax revenues published by the International Centre for Tax and Development (ICTD). The findings indicate that the substantial decline in direct tax revenues necessitated a search for alternative sources of income. The separate taxation system for cryptocurrencies has legitimized digital assets and enabled the government to monitor transactions and capital gains. The introduction of the "Digital Rupee" aims to enhance the digital economy through efficient currency management. This research highlights the need for policymakers to develop a well-defined regulatory framework for cryptocurrency taxation. Clear regulations on cryptocurrency taxation and the "Digital Rupee" could help India boost its digital economy while ensuring better monitoring of crypto transactions and revenues.

Economic Valuation of Ecosystem Services of Coastal Area of Kinondoni District, Tanzania

This study investigates the often overlooked economic values of ecosystem services in the coastal area of Kinondoni District, Tanzania, in the context of spatial and temporal changes in land use and land cover (LULC). The primary objectives were to assess how ecosystem services and functions have been affected by LULC changes over a 30-year period, from 1993 to 2023. The study employs a benefit transfer method, integrating local and global estimations of ecosystem service value (ESV) with field survey, remote sensing and GIS techniques. The findings reveal that the annual changes in ESV during the study period are estimated at US$ 0.024 million and US$ 0.034 million using local and global coefficients, respectively. Over the three decades, there has been a significant annual loss of US$ 0.72 million locally and US$ 2.11 million globally, primarily due to the degradation of mangrove forests and bushland. The decline in ecosystem functions is largely driven by reductions in regulating services, which account for 54.1% of the total decrease in local valuations and 31.6% in global valuations. Supporting services also experienced substantial declines, with reductions of 39.7% in local valuations and 55.8% in global valuations. The study underscores the urgent need to review and enhance management and conservation strategies to ensure the sustainability of the coastal ecosystems in Kinondoni District, Tanzania.

Evaluation of ComBat Harmonization for Reducing Across-Tracer Differences in Regional Amyloid PET Analyses.

Differences in amyloid positron emission tomography (PET) radiotracer pharmacokinetics and binding properties lead to discrepancies in amyloid-β uptake estimates. Harmonization of tracer-specific biases is crucial for optimal performance of downstream tasks. Here, we investigated the efficacy of ComBat, a data-driven harmonization model, for reducing tracer-specific biases in regional amyloid PET measurements from [18F]-florbetapir (FBP) and [11C]-Pittsburgh compound-B (PiB). One hundred thirteen head-to-head FBP-PiB scan pairs, scanned from the same subject within 90 days, were selected from the Open Access Series of Imaging Studies 3 (OASIS-3) dataset. The Centiloid scale, ComBat with no covariates, ComBat with biological covariates, and GAM-ComBat with biological covariates were used to harmonize both global and regional amyloid standardized uptake value ratios (SUVR). Variants of ComBat, including longitudinal ComBat and PEACE, were also tested. Intraclass correlation coefficient (ICC) and mean absolute error (MAE) were computed to measure the absolute agreement between tracers. Additionally, longitudinal amyloid SUVRs from an anti-amyloid drug trial were simulated using linear mixed effects modeling. Differences in rates-of-change between simulated treatment and placebo groups were tested, and change in statistical power/Type-I error after harmonization was quantified. In the head-to-head tracer comparison, ComBat with no covariates was the best at increasing ICC and decreasing MAE of both global summary and regional amyloid PET SUVRs between scan pairs of the same group of subjects. In the clinical trial simulation, harmonization with both Centiloid and ComBat increased statistical power of detecting true rate-of-change differences between groups and decreased false discovery rate in the absence of a treatment effect. The greatest benefit of harmonization was observed when groups exhibited differing FBP-to-PiB proportions. ComBat outperformed the Centiloid scale in harmonizing both global and regional amyloid estimates. Additionally, ComBat improved the detection of rate-of-change differences between clinical trial groups. Our findings suggest that ComBat is a viable alternative to Centiloid for harmonizing regional amyloid PET analyses.

Superinertial Internal Tides Propagating along the Coast: Dynamics and Energetics Revealed through Topographic Modes

Abstract Internal tides are an important energy source for diapycnal mixing in the ocean interior. Subinertial internal tides are known to have a cross-sectional structure that is baroclinic in deep areas but more barotropic in shallower areas, making the conventional barotropic–baroclinic decomposition ineffective to separate internal tides from surface tides. To address this issue, Tanaka introduced a “topographic mode” which represents internal motions with a barotropic vertical structure and proposed a new energy diagram enabling us to quantify the generation of subinertial internal tides. Here, the applicability of this new energy diagram to superinertial internal tides at various latitudes is investigated by idealized numerical experiments with uniform surface tides passing over a continental slope with a bump in the coastline. The calculated results show that both the topographic and baroclinic modes are generated over the bump and propagate downstream along the coast, inseparably forming a topographically modified internal Kelvin wave whose cross-sectional structure closely resembles that obtained by solving a two-dimensional eigenvalue problem for a superinertial frequency. The energy conversion rate from the surface mode to the topographic mode is about half of the energy conversion rate from the surface mode to the baroclinic mode when the tidal frequency is slightly superinertial and maintains a nonnegligible contribution even when the tidal frequency is substantially superinertial. The findings of this study indicate that the new energy diagram can be applied seamlessly across the critical latitudes and possibly provides a global distribution of the internal tide generation significantly larger than the previous estimates. Significance Statement Quantifying the generation of internal tides is essential for accurate climate modeling, since they are a major energy source of vertical mixing in the ocean. It is known that diurnal internal tides change their characteristics poleward of 30° latitude, where their motion is dominated by horizontal rotation rather than vertical oscillation. This study demonstrates that a recently proposed energy diagram for quantifying the generation of diurnal internal tides poleward of 30° latitude is also effective equatorward of 30° latitude. This is because the rotational motion remains significant even equatorward of 30° latitude, being a fundamental component of the internal tides over a sloping seafloor. The application of this energy diagram will improve the global estimate of internal tide generation.

The ALMA-CRISTAL survey: Dust temperature and physical conditions of the interstellar medium in a typical galaxy at z = 5.66

We present new λrest = 77 μm dust continuum observations from the Atacama Large Millimeter/submillimeter Array of HZ10 (CRISTAL-22). This dusty main sequence galaxy at z = 5.66 was observed as part of the [CII] Resolved Ism in STar-forming Alma Large program (CRISTAL). The high angular resolution of the ALMA Band 7 and new Band 9 data (∼0′′​​.4) reveals the complex structure of HZ10, which comprises two main components (HZ10-C and HZ10-W), along with a bridge-like dusty emission between them (i.e., “the bridge”). Using a modified blackbody function to model the dust spectral energy distribution (SED), we constrained the physical conditions of the interstellar medium (ISM) and its variations among the different components identified in HZ10. We find that HZ10-W (the more UV-obscured component) has an SED dust temperature of TSED ∼ 51.2 ± 13.1 K; this was found to be ∼5 K higher (which is statistically insignificant; i.e., less than 1σ) than that of the central component and previous global estimations for HZ10. Our new ALMA data allow us to reduce the uncertainties of global TSED measurements by a factor of ∼2.3, compared to previous studies. The HZ10 components have [CII]-to-far-infrared (FIR) luminosity ratios and FIR surface densities values that are consistent with local starburst galaxies. However, HZ10-W shows a lower [CII]/FIR ratio compared to the other two components (albeit still within the uncertainties), which may suggest a harder radiation field destroying polycyclic aromatic hydrocarbon associated with [CII] emission (e.g., active galactic nuclei or young stellar populations). While HZ10-C appears to follow the tight IRX-βUV relation seen in local UV-selected starburst galaxies and high-z star-forming galaxies, we find that both HZ10-W and the bridge depart from this relation and are well described by dust-screen models with holes in front of a hard UV radiation field. This suggests that the UV emission, which is likely coming from young stellar populations, is strongly attenuated in the “dustier” components of the HZ10 system.