bluuebunny/crossref_metadata_2025 huggingface dataset:
Risks beyond the ditch: Copper Age tannery from the settlement of Kamianets-Podilskyi (Tatarysky), Ukraine
Authors: Sobkowiak-Tabaka Iwona , Gerasimenko Natalia , Kurzawska Aldona , Kufel-Diakowska Bernadeta , Moskal-del Hoyo Magdalena , Stróżyk Mateusz , Rohozin Yevhenii P. , Ridush Bogdan , Levinzon Yevhenii , Boltaniuk Petro , Nechytailo Pavlo , Diachenko Aleksandr
Published: March 2024

The evolution of Neolithic to Bronze Age settlement organization in Central Europe has revealed ditches as an important component of settlement structures. The various shapes and sizes of these features contribute to different understandings of their functions, mainly referring to ditches as elements of fortifications or ritual practices. Based on a newly discovered Copper Age feature at Kamianets-Podilskyi (Tatarysky), Ukraine, our paper contributes to the discussion on the function of ditches in their relation to prehistoric technologies. This study presents evidence on tanning techniques and technologies associated with a section of ditch belonging to the Western Trypillia culture. Due to the uniqueness of this discovery, we applied various analyses, including GIS spatial analyses, palynological, anthracological, archeozoological, malacological, and use-wear studies. The obtained results enable us to recognize the complex practices of Copper Age communities, skillfully combining technical knowledge with an understanding of environmental conditions.
Enhancing collagen based nanoemulgel for effective topical delivery of Aceclofenac and Citronellol oil: Formulation, optimization, in-vitro evaluation, and in-vivo osteoarthritis study with a focus on HMGB-1/RAGE/NF-κB pathway, Klotho, and miR-499a
Authors: Aldeeb Reem Abd Elhameed , Ibrahim Sherihan Salaheldin Abdelhamid , Khalil Islam Ahmed , Ragab Ghada Mohamed , El-Gazar Amira Ahmed , Taha Amal Anwar , Hassan Doaa Hussien , Gomaa Asmaa Ahmed , Younis Mona Kamal
Published: March 2024

The majority of conventional osteoarthritis (OA) treatments are based on molecular adjustment of certain signaling pathways associated with osteoarthritis (OA) pathogenesis, however there is a significant need to search for more effective and safe treatments. This study centers around formulating Aceclofenac (ACF) with high bioavailability in combination with Citronellol oil and collagen. The optimal concentrations of Citronellol oil/D-Limonene oil, Tween 80, and Transcutol HP were determined using a pseudoternary phase diagram. The formulated nanoemulsions were studied for thermophysical stability. Thermodynamically stable formula were analyzed for droplet size, zeta potential, and in-vitro permeation. Then, collagen based nanoemulsion were prepared to capitalize on its efficacy in reducing osteoarthritis side effects and characterized for nano size properties. Formulae F10 and F10C were chosen as optimum nanosize formula. Hense, they were prepared and characterized as nanoemulgel dosage form. The nanoemulgel formulae F10NEG1 and F10CNEG1 showed reasonable viscosity and spreadability, with complete drug release after 4 h. These formulae were chosen for further In vivo anti-OA study. Collagen based ACF/citronellol emugel were able to modulate HMGB-1/RAGE/NF-κB pathway, mitigating the production of inflammatory cytokine TNF-α. They were also able to modulate Klotho and miR-499, reducing serum CTXII and COMP, by reducing the cartilage destruction. Histological investigations validated the efficacy, safety, and superiority of Aceclofenac in combination with Citronellol oil and collagen (F10CNEG1) over solo the treated group (F10NEG1 and blank). Hence, the findings of the current work encourage the use of this promising combined formula in treatment of OA patients.

Graphical abstract
Progressive multifocal leukoencephalopathy associated with systemic lupus erythematosus: longitudinal observation of lymphocytes, JC virus in cerebrospinal fluid, and brain magnetic resonance imaging
Authors: Yamada Hidetada , Toko Megumi , Nakamori Masahiro , Ueno Hiroki , Aoki Shiro , Sugimoto Tomohiro , Yasutomi Hiroko , Nakamichi Kazuo , Maruyama Hirofumi
Published: March 2024

Progressive multifocal leukoencephalopathy (PML) rarely occurs in patients with systemic lupus erythematosus (SLE). This report presents the case of a patient who developed PML due to SLE-associated multiple factors. A 60-year-old woman diagnosed with SLE undergoing multiple immunosuppressive therapies, including azathioprine, presented with cerebral cortical symptoms, lymphocytopenia, and vitamin B12 deficiency and was subsequently diagnosed with SLE-associated PML. We evaluated the cause and disease activity of PML, focusing on the longitudinal assessment of lymphocytopenia, JC virus (JCV) DNA copy number in the cerebrospinal fluid, and magnetic resonance imaging (MRI) findings. Discontinuing azathioprine and initiating alternative immunosuppressive treatments with intramuscular vitamin B12 injections affected lymphocytopenia and disease management. However, despite recovery from lymphopenia and JCV DNA copy number being low, the large hyperintense and punctate lesions observed on the fluid-attenuated inversion recovery (FLAIR) images exhibited varying behaviors, indicating that the balance between contributing factors for PML may have fluctuated after the initial treatment. Clinicians should be meticulous when assessing the underlying pathology of the multifactorial causes of PML due to SLE. The difference in the transition pattern of these lesions on FLAIR images may be one of the characteristics of MRI findings in PML associated with SLE, reflecting fluctuations in disease activity and the progression stage of PML.
Excess mortality in patients with non-functioning pituitary adenoma: a systematic review and meta-analysis
Authors: Bioletto F. , Sibilla M. , Gasco V. , Ghigo E. , Grottoli S.
Published: March 2024

Background

Patients with non-functioning pituitary adenoma (NFPA) often present with a variety of clinical manifestations and comorbidities, mainly determined by the local mass effect of the tumor and by hypopituitarism. Whether this has an impact on overall mortality, however, is still unclear.

Methods

PubMed/Medline, EMBASE, and Cochrane Library databases were systematically searched until May 2023 for studies reporting data either about standardized mortality ratios (SMRs) or about predictors of mortality in patients with NFPA. Effect sizes were pooled through a random-effect model. This systematic review and meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO, #CRD42023417782).

Results

Eleven studies were eligible for inclusion in the systematic review; among these, five studies reported data on SMRs, with a total follow-up time of approximately 130,000 person-years. Patients with NFPA showed an increased mortality risk compared to the general population (SMR = 1.57 [95%CI: 1.20–1.99], p < 0.01). Age and sex appeared to act as effect modifiers, with a trend towards higher SMRs in females (SMR = 1.57 [95%CI: 0.91–2.41], p = 0.10) than in males (SMR = 1.00 [95%CI: 0.89–1.11], p = 0.97), and in patients diagnosed at age 40 years or younger (SMR = 3.19 [95%CI: 2.50–3.97], p < 0.01) compared to those with later onset of the disease (SMR = 1.26 [95%CI: 0.93–1.65], p = 0.13). The trend towards excess mortality was similar in patients with normal (SMR = 1.22 [95%CI: 0.94–1.53], p = 0.13) or deficient (SMR = 1.26 [95%CI: 0.82–1.79], p = 0.27) pituitary function.

Conclusions

Excess mortality is observed in patients with NFPA, regardless of pituitary function, especially in women and in patients with a younger age at diagnosis.
Education, educational mismatch and occupational status: an analysis using PIAAC data
Authors: Huertas Inés P. Murillo , Raymond José L.
Published: March 2024

The aim of this paper is to estimate the effect of longer schooling on the probability of entering a high-skill job and analyse whether the size of this effect depends on the (mis)match between the education attained by workers and the education required by the jobs. We use PIAAC data to estimate a multinomial logit model that predicts the odds of working in each occupational category and then simulate how these probabilities change for workers who have completed one more year of education, broken down by whether or not this additional year matches the educational requirements of the job. Our results suggest that, as observed from wages estimated according to an ORU equation, better education is positively associated with better jobs but the increased probability of getting a high-skill job as a result of completing one more year of education is greater for required than for mismatched education. The results differ notably by gender, with women being the ones who benefit most from an increase in education, especially in the absence of educational mismatch. These trends are observed whatever the institutional context, but we also found noteworthy differences by country.
Vom „rule of law revival“ zum „rule of law backsliding“: Ein Erklärungsversuch
Authors: von Steinsdorff Silvia
Published: March 2024

Gezielte Angriffe auf die rechtsstaatlichen Elemente konstitutioneller Demokratie sind ein zentraler Bestandteil des weltweit zu beobachtenden „democratic backsliding“. Teilweise lassen sie sich als Reaktion auf die mitunter unreflektierte, mechanistische Rechtsstaatsgläubigkeit der Demokratisierungsforschung und -politik der vergangenen 20 Jahre erklären. Allerdings missbrauchen autoritär-populistische Anti-Demokraten, die selbst in (noch) konsolidierten Demokratien gegenwärtig an Einfluss gewinnen, diese berechtigte Kritik, um ihre anti-pluralistischen Vorstellungen von einem angeblich homogenen Volkswillen und einer unumschränkten Mehrheitsherrschaft zu propagieren. Gegen diese Gefahren des „rule of law backsliding“ hilft nur eine klare Benennung des oft negierten Spannungsverhältnisses zwischen Rechtsstaat und Demokratie und die konstruktive Suche nach einer Balance zwischen beiden Prinzipien im Rahmen des demokratischen Verfassungsstaates.
The OPS-SAT case: A data-centric competition for onboard satellite image classification
Authors: Meoni Gabriele , Märtens Marcus , Derksen Dawa , See Kenneth , Lightheart Toby , Sécher Anthony , Martin Arnaud , Rijlaarsdam David , Fanizza Vincenzo , Izzo Dario
Published: March 2024

While novel artificial intelligence and machine learning techniques are evolving and disrupting established terrestrial technologies at an unprecedented speed, their adaptation onboard satellites is seemingly lagging. A major hindrance in this regard is the need for high-quality annotated data for training such systems, which makes the development process of machine learning solutions costly, time-consuming, and inefficient. This paper presents “the OPS-SAT case”, a novel data-centric competition that seeks to address these challenges. The powerful computational capabilities of the European Space Agency’s OPS-SAT satellite are utilized to showcase the design of machine learning systems for space by using only the small amount of available labeled data, relying on the widely adopted and freely available open-source software. The generation of a suitable dataset, design and evaluation of a public data-centric competition, and results of an onboard experimental campaign by using the competition winners’ machine learning model directly on OPS-SAT are detailed. The results indicate that adoption of open standards and deployment of advanced data augmentation techniques can retrieve meaningful onboard results comparatively quickly, simplifying and expediting an otherwise prolonged development period.
Application of deep learning in iron ore sintering process: a review
Authors: Gong Yu-han , Wang Chong-hao , Li Jie , Mahyuddin Muhammad Nasiruddin , Seman Mohamad Tarmizi Abu
Published: March 2024

In the wake of the era of big data, the techniques of deep learning have become an essential research direction in the machine learning field and are beginning to be applied in the steel industry. The sintering process is an extremely complex industrial scene. As the main process of the blast furnace ironmaking industry, it has great economic value and environmental protection significance for iron and steel enterprises. It is also one of the fields where deep learning is still in the exploration stage. In order to explore the application prospects of deep learning techniques in iron ore sintering, a comprehensive summary and conclusion of deep learning models for intelligent sintering were presented after reviewing the sintering process and deep learning models in a large number of research literatures. Firstly, the mechanisms and characteristics of parameters in sintering processes were introduced and analysed in detail, and then, the development of iron ore sintering simulation techniques was introduced. Secondly, deep learning techniques were introduced, including commonly used models of deep learning and their applications. Thirdly, the current status of applications of various types of deep learning models in sintering processes was elaborated in detail from the aspects of prediction, controlling, and optimisation of key parameters. Generally speaking, deep learning models that could be more effectively implemented in more situations of the sintering and even steel industry chain will promote the intelligent development of the metallurgical industry.
Exploring Potential Referral Pathways for Renal Artery Denervation and Developing a Centre of Excellence in Ireland
Authors: Leahy Niall , Wagener Max , Shahzad Shirjeel , Murphy Darragh , McMorrow Amy , Coen Eileen , Sharif Ruth , Sharif Faisal
Published: March 2024

Arterial hypertension is one of the most significant and prevalent risk factors for cardiovascular disease. Despite widespread awareness of the condition, as well as a multitude of available antihypertensive drug classes, rates of uncontrolled hypertension remain high on a global scale. Frequently, poor compliance with anti-hypertensive medication plays a big role in patients’ inability to attain adequate blood pressure control. In individuals with resistant and/or uncontrolled hypertension, renal denervation is an emerging device-based therapy that has shown to be efficacious and safe in reducing blood pressure in several sham controlled trials. Additionally, it represents a treatment option for patients intolerant to oral pharmacotherapy.

University Hospital Galway has been performing renal denervation procedures over the past number of years within multicentre, international sham-controlled trials and registries. Representing a novel and emerging antihypertensive treatment option, sources of referral for renal denervation are diverse and multiple; thus, there is an unmet need for standardised referral structures in Ireland. Herein, we review current and developing referral pathways for renal denervation at our institution, and discuss streamlined patient management and requirements to establish a centre of excellence.
Utilizing ensemble learning in the classifications of ductile and brittle failure modes of UHPC strengthened RC members
Authors: Taffese Woubishet Zewdu , Zhu Yanping , Chen Genda
Published: March 2024

This study aims to achieve the swift and precise classification of ductile and brittle failure modes in flexural reinforced concrete (RC) members, specifically those with tension sides strengthened by ultrahigh performance concrete (UHPC). Employing six ensemble learning techniques—Bagging, Random Forest, AdaBoost, Gradient Boosting, XGBoost, and LightGBM—the authors utilize a comprehensive dataset comprising 14 features, which include manually labeled failure modes obtain from load–deflection curves. The model training spans four scenarios, varying in the inclusion or exclusion of features describing the cross-sectional area of RC members and moment resistance. XGBoost emerges as the most effective classifier, achieving an impressive 84% accuracy with high confidence. Additionally, the study employs the Shapley Additive Explanation (SHAP) technique on the best-performing model to illuminate the significance and impacts of various features in UHPC-strengthened flexural members’ failure modes. Notably, moment resistance and UHPC tensile strength surface as the most influential factors in predicting failure modes. Increased rebar yield strength, UHPC compressive strength, UHPC reinforcement ratio, and steel fiber volume in UHPC contribute to enhanced ductility in flexural members, while heightened moment resistance and UHPC layer thickness, along with a robust RC-UHPC interface, tend to induce brittleness. The introduction of such an effective failure modes classification model, coupled with the model’s explainability, instills trust in its predictions and facilitates seamless integration into real-world applications, particularly in seismic areas. The model’s ability to operate without the need for pre-experimental tests marks a significant advancement in the field.
Race, Taste and the Grape
Authors: Nugent Paul
Published: March 2024

With the introduction of wine to the Cape Colony, it became associated locally with social extremes: with the material trappings of privilege and taste, on the one side, and the stark realities of human bondage, on the other. By examining the history of Cape wine, Paul Nugent offers a detailed history of how, in South Africa, race has shaped patterns of consumption. The book takes us through the Liquor Act of 1928, which restricted access along racial lines, intervention to address overproduction from the 1960s, and then latterly, in the wake of the fall of the Apartheid regime, deregulation in the 1990s and South Africa's re-entry into global markets. We see how the industry struggled to embrace Black Economic Empowerment, environmental diversity and the consumer market. This book is an essential read for those interested in the history of wine, and how it intersects with both South African and global history.
Sixty Years of Visible Protest in the Disability Struggle for Equality, Justice, and Inclusion
Authors: Pettinicchio David
Published: March 2024

Visible protests reflect both continuity and change. This Element illustrates how protest around longstanding issues and grievances is punctuated by movement dynamics as well as broader cultural and institutional environments. The disability movement is an example of how activist networks and groups strategically adapt to opportunity and threat, linking protest waves to the development of issue politics. The Element examines sixty years of protest across numerous issue areas that matter for disability including social welfare, discrimination, transportation, healthcare, and media portrayals. Situating visible protest in this way provides a more nuanced picture of cycles of contention as they relate to political and organizational processes, strategies and tactics, and short-and-long-term outcomes. It also provides clues about why protest ebbs and flows, when and how protest matters, who it matters for, and for what.
Rethinking Church–State Relations in Seventeenth-Century Philippines: The Guerrero-Hurtado de Corcuera and Pardo-Audiencia Controversies
Authors: Coello de la Rosa Alexandre
Published: March 2024

The early modern Philippine archipelago is often described as being under the power of a frailocracy with a far-reaching impact. From a microhistorical approach of ecclesiastical contentiousness, I argue that the intermittent clashes between and inside the two pillars of colonial rule—the civil and ecclesiastical powers—belie the church's overarching control over state affairs. The church was not a monolithic unit in the Philippines, but was rather highly fragmented, especially in distant Asian enclaves, and it was not independent, but relied on royal patronage, diplomacy, and transnational networks. Using archival materials, official reports, religious manifestos, and royal appointments and decrees, I focus upon two significant case studies of the two exiled archbishops of Manila, Fray Hernando Guerrero, OSA, and Felipe Pardo, OP, to explore factionalism, negotiation, and microlevel political constellations as a way to approach conflicting church–state relations in seventeenth-century Philippines from a more nuanced perspective.
Potential contribution of agronomic practices and conservation agriculture towards narrowing smallholders’ yield gaps in Southern Africa: lessons from the field
Authors: Nyagumbo Isaiah , Nyamayevu Donald , Chipindu Lovemore , Siyeni Donald , Dias Domingos , Silva João Vasco
Published: March 2024

Smallholders in Southern Africa continue to grapple with low maize productivity despite this being the staple food crop. This study sought to analyze and isolate the relative contribution of agronomic practices to maize yields obtained by smallholders in Malawi and Mozambique using data generated from on-farm trials testing the performance of conservation agriculture cropping systems. The trials were implemented in two communities, namely Kasungu district in Malawi and Sussundenga district in Mozambique, and ran for seven consecutive growing seasons starting in 2010–2011. Maize yield was measured annually in the on-farm trials, which included a ‘control treatment’ representing an improved farm practice, and in neighboring fields managed by the same farmers on their own, hence representing a ‘true farm practice’. Results indicated that maize yield increased linearly with increasing plant population at harvest at both sites. On average, an increase in plant population at harvest by 1000 plants ha–1 resulted in an increase in maize yield of 90 and 63 kg ha–1 at Kasungu and Sussundenga, respectively. The greatest maize yields were obtained when plant population at harvest exceeded 40 000 plants ha–1. Yet, the plant population at harvest was below the generally recommended optimum for most of the cropping systems studied and in most growing seasons. Furthermore, the use of agronomic practices alone without conservation agriculture (i.e., improved varieties, fertilizer management, and timely weed control) resulted in maize yield gains of as much as 54% and 43% relative to the ‘true farm practice’ at Kasungu and Sussundenga, respectively. Overall, the proportion of these yield increases relative to the ‘true farm practice’ accounted for by agronomic practices amounted to 53–70% and 57–85% at Kasungu and Sussundenga for the highest to the lowest-yielding cropping system. Although conservation agriculture significantly improved maize yield at both sites, such increases were smaller in magnitude compared to the yield gains derived from improved agronomic practices. The study suggests that considerable strides toward narrowing maize yield gaps in Southern Africa can be achieved through improvement of current crop management practices, let alone adhering to the conservation agriculture principles of minimum tillage, residue retention, and crop diversification.
Collisional rate coefficients for astrophysics
Authors: Faure Alexandre
Published: March 2024

In the interstellar medium, inelastic collisions are so rare that they cannot maintain a local thermodynamical equilibrium (LTE). Atomic and molecular populations therefore do not follow a simple Boltzmann distribution and non-LTE spectra are the rule rather than the exception. In such conditions, accurate state-to-state collisional data are crucial for a quantitative interpretation of spectra. In recent years, considerable progress has been made in quantum calculations of inelastic cross sections for a variety of targets, types of transitions and projectiles. For a few benchmark species, detailed comparisons between theory and experiment were also carried out at the state-to-state level and in the quantum regime. In this article, we highlight such comparisons for three important molecules: CO, H2O and CH+. We also describe current computational efforts to extend these advances to ever larger targets, new transition types, and new environments (e.g. stellar envelopes or cometary atmospheres).
Contribution of small telescopes at the Oukaïmden observatory in Morocco to study atmospheric dynamics and shocks waves in variables stars RR Lyr and R Scuti
Authors: Benhida A. , Sefyani F. L. , Chafouai K. , El Jariri Y. , Chouqar J. , Benkhaldoun Z. , Kolenberg K. , Sylla S.
Published: March 2024

Through Spectroscopy, we aim to develop the field of pulsating stars, especially the atmospheric dynamics of high amplitude pulsators such as RR Lyr and R Scuti, in order to establish new models of the mechanical and thermal behavior of their atmospheres (shock waves, relaxation time, energy loss…). We used high-resolution spectra over a total of 81 nights from made with the spectrograph Eshell during years 2013 and 2015 runs from Oukaïmeden observatory in the High Atlas mountains (Morocco) completed with made with the spectrograph ELODIE (Haute Provence observatory, France) during years 1994–1997. A detailed analysis of line profile variations over the whole pulsation cycle is performed. Shock wave velocity and lines intensity were used as indicators of atmospheric dynamics activities. We have obtained and compared our results with those obtained by the large telescopes, we have obtained thanks to our site very satisfactory results, Indeed : For RR lyr: For the first time the second apparition of Helium (D3) was detected using our Telescope (0.35m) at Oukaïmeden Observatory.

For the first time, during the phase of expansion of the star, the emission of the line D3 is visible on various phases Blazhko, including during the minimum of the cycle Blazhko.

Also, we presented the results of a long- term, high-resolution spectroscopic study of the variable star R Sct. We analyzed the features of the optical spectra of this object and found RSct shows irregular behavior in its slight variations for much of the time that it was observed. Its average period is close to 142 d, but some- times the irregularities are so strong that it is not possible to define a periodic variation.
Charlotte Emma Moore Sitterly: She “turned chaos into order”
Authors: DeVorkin David H.
Published: March 2024

At the 1988 IAU General Assembly in Baltimore, among many who offered reminiscences of earlier meetings was Charlotte Moore Sitterly. She first attended the 1932 GA meeting, in Cambridge, Mass., though she already “helped to assemble material for delegates” since the 1920s, for astronomers at Princeton, Mount Wilson and Lick Observatory. She was an ardent member of the new Commission 14 (then called “Fundamental Spectroscopic Data”), eventually becoming its president. In her 1988 reminiscence, she recalled that the Commission meeting was sparsely attended and very informal, but astronomers’ “never-ending demand for tables and data analysis” soon changed all that (Sitterly 1988). Here we provide a brief overview of how Charlotte Moore Sitterly came to be at the very center of that change, which Donald Menzel early on described as having “turned chaos into order” and just a “little short of miraculous” (Menzel 1928) We will recount highlights of her early life, aspirations, training, and contributions during her years at Princeton, Berkeley, Mount Wilson, and the National Bureau of Standards.
Deep Fault‐Controlled Fluid Flow Driving Shallow Stratigraphically Constrained Gas Hydrate Formation: Urutī Basin, Hikurangi Margin, New Zealand
Authors: Gorman Andrew R. , Crutchley Gareth J. , Baker Dylan R. , Fraser Douglas R. A. , Henrys Stuart A. , Tréhu Anne M. , Harris Robert N. , Phrampus Benjamin J. , Pecher Ingo A.
Published: March 2024

The Hikurangi Margin east of New Zealand's North Island hosts an extensive gas hydrate province with numerous gas hydrate accumulations related to the faulted structure of the accretionary wedge. One such hydrate feature occurs in a small perched upper‐slope basin known as Urutī Basin. We investigated this hydrate accumulation by combining a long‐offset seismic line (10‐km‐long receiver array) with a grid of high‐resolution seismic lines acquired with a 600‐m‐long hydrophone streamer. The long‐offset data enable quantitative velocity analysis, while the high‐resolution data constrain the three‐dimensional geometry of the hydrate accumulation. The sediments in Urutī Basin dip landward due to ongoing deformation of the accretionary wedge. These strata are clearly imaged in seismic data where they cross a distinct bottom simulating reflection (BSR) that dips counterintuitively in the opposite direction to the regional dip of the seafloor. BSR‐derived heat flow estimates reveal a distinct heat flow anomaly that coincides spatially with the upper extent of a landward‐verging thrust fault. We present a conceptual model of this gas hydrate system that highlights the roles of fault‐controlled fluid flow at depth merging into strata‐controlled fluid flow into the hydrate stability zone. The result is a layer‐constrained accumulation of concentrated gas hydrate in the dipping strata. Our study provides new insight into the interplay between deep faulting, fluid flow and gas hydrate formation within an active accretionary margin.
A Simple, Low‐Blank Batch Purification Method for High‐Precision Boron Isotope Analysis
Authors: Trudgill M. , Nuber S. , Block H. E. , Crumpton‐Banks J. , Jurikova H. , Littley E. , Shankle M. , Xu C. , Steele R. C. J. , Rae J. W. B.
Published: March 2024

Boron (B) isotopes are widely used in the Earth sciences to trace processes ranging from slab recycling in the mantle to changes in ocean pH and atmospheric CO2. Boron isotope analysis is increasingly achieved by multi‐collector inductively coupled plasma mass spectrometry, which requires separation of B from the sample matrix. Traditional column chromatography methods for this separation have a well‐established track record but are time consuming and prone to contamination from airborne blank. Here, we present an extensive array of tests that establish a novel method for B purification using a batch method. We discuss the key controls and limitations on sample loading, matrix removal and B elution including sample volume, ionic strength, buffer to acid ratio and elution volume, all of which may also help optimize column‐based methods. We find consistent, low procedural blanks of 10 ± 16 pg and excellent reproducibility: 10 ng NIST RM 8301 foram [8301f] yields 14.58 ± 0.11‰ 2SD n = 15; 2.5 ng 8301f yields 14.60 ± 0.19‰ 2SD, n = 31; and overall long term 2SD on n = 218 samples pooling different sample sizes yields 14.62 ± 0.21‰ 2SD. This method also offers significant advantages in throughput, allowing the processing of 24 samples in ∼5 hr. This boron batch method thus provides a fast, reproducible, low‐blank method for purification of boron for high precision isotopic analyses.
Long‐Term Variability of Mars' Exosphere Density Based on Precise Orbital Analysis of Mars Reconnaissance Orbiter and Mars Odyssey
Authors: Forbes J. M. , Bruinsma S. L. , Zhang X. , Marty J.‐C. , Laurens S.
Published: March 2024

The variability of Mars exosphere over monthly to solar‐cycle scales at 251 and 412 km altitude is quantified by analysis of 41‐Ls mean densities derived from precise orbit determination of the Mars Reconnaissance Orbiter (MRO) and Mars Odyssey (MO) satellites, respectively. The data encompass 2006–2020 (MRO) and 2002–2020 (MO). At both altitudes, most of the variance is captured by cos(Ls–ϕ), where ϕ ≈ 258°. This term represents the effects of solar heating changes due to the eccentricity of Mars orbit around the Sun, and climatological changes in heating due to lower‐atmosphere dust loading, which does not play a significant role. The remaining variability is connected with the “irregular” variability of solar flux over monthly time scales. For MO, the presence of Helium disrupts a clean correlation with these sources.
Moisture Sources and Pathways of Annual Maximum Precipitation in the Lancang‐Mekong River Basin
Authors: Zhang Shuyu , Zhang Gengxi , Gong Guoqing , Gan Thian Yew , Chen Deliang , Liu Junguo
Published: March 2024

Recent extremely heavy precipitation has led to substantial economic losses and affected millions of residences in the Lancang‐Mekong River Basin (LMRB). This study analyzed the spatial‐temporal characteristics of the annual maximum precipitation (R1X) of the LMRB and identified the moisture sources and pathways conducive to R1Xs using a Lagrangian back trajectory model. Results show that India Ocean and Bay of Bengal (IO/BOB), local evapotranspiration, and West Pacific Ocean and East China (WP/EC) are the three main moisture transport pathways of the R1Xs in LMRB, contributing 68.3%, 20.4% and 11.3% of the trajectories, respectively. R1Xs in the downstream eastern area are affected by tropical cyclones bringing large amounts of moisture from the WP/EC. As tropical cyclones shifted northward under climate change impact, more extreme precipitation occurred over the LMRB due to moisture coming from WP/EC, but those from the IO/BOB had decreased because of the slowdown of flows across the Equator.
Inferring Global Ocean Mass Increase From Tide Gauges Network With Climate Models
Authors: Mu Dapeng , Huang Ruhui , Xu Tianhe , Yan Haoming
Published: March 2024

Ocean mass increase contributes to global sea level rise, and plays an important role in understanding climate change. Here, we develop a data assimilation approach that enables the inference of ocean mass increase from global tide gauge network. This approach incorporates outputs from climate models and sea level fingerprints caused by water mass changes over land areas. The results suggest a trend of 2.15 ± 0.72 mm/yr for ocean mass increase over the period 1993–2022, which closes the global sea level budget with estimates of thermosteric sea level rise. Furthermore, the inferred ocean mass increase offers an insight into the causes of sea level rise since 1950. These findings emphasize the significance of climate models, in addition to simulating sea level changes, they contribute to understanding causes of sea level rise over the past decades.
Determining the Influence of the IMF and Planetary Magnetic Field Models on Mercury's Magnetosphere Along Spacecraft Trajectories of MESSENGER, BepiColombo and MPO
Authors: Exner Willi , Griton Léa S. , Heyner Daniel
Published: March 2024

Mercury's planetary magnetic field models (PMFMs) agree on a majorly dipolar field structure with a northward shift of the magnetic equator. However, due to the northerly biased orbit coverage of past spacecraft missions and different data analyzing methods, the available PMFMs differ in the determined multipole magnitudes for the dipole, quadrupole and octupole moments. While the PMFMs agree well with northern observations, we find that the predicted magnetic field values differ in the unexplored equatorial and southern regions. In the forward modeling approach of this study, we apply three different PMFM representatives, differing in their values of the dipole, quadrupole and octupole moments, and model the resulting solar wind interaction via a global hybrid model with sets of the 4 most common interplanetary magnetic field (IMF) directions under otherwise average solar wind conditions. Extracting our modeled fields along the flybys of MESSENGER and BepiColombo, as well as along four representative orbits of the Mercury Planetary Orbiter (MPO), allows us to estimate local field variations due to IMF and PMFM influence. Our modeled magnetic field components separate significantly by up to 60 nT between the PMFMs in low‐altitude southern regions, leading to displacements of magnetopause, cusps and current sheet locations. We find that MESSENGER flyby observations agree best with modeled field ranges resulting from a quadrupolar PMFM and that certain nightside regions are useful to estimate upstream IMF polarity. We also demonstrate how comparing BepiColombo swingby and MPO orbit phase observations with modeled results can help determine the correct PMFM for Mercury.
Spatial Scales of Kinetic Energy in the Arctic Ocean
Authors: Liu Caili , Wang Qiang , Danilov Sergey , Koldunov Nikolay , Müller Vasco , Li Xinyue , Sidorenko Dmitry , Zhang Shaoqing
Published: March 2024

Despite the importance of the Arctic Ocean for the large‐scale circulation and climate, there is still a knowledge gap in our understanding of the spatial characteristics of the Arctic Ocean circulation, especially for the mesoscale. This paper investigates the spatial characteristics of the Arctic Ocean circulation using a simulation with 1 km horizontal resolution. We revealed that there are two peaks in the kinetic energy (KE) spectral density at the 400 m depth, one at the gyre scale of the Arctic Circumpolar Boundary Current (centered at 1,700–2,000 km), and the other associated with the mesoscale (at about 60 km). However, at the 70 m depth, the boundary currents tend to mask the spectrum peak associated with the mesoscale. The KE spectrum exhibits a power‐law scaling typical for ocean eddies. We found that about 80% (50%) of the KE is on scales smaller than 100 km (30 km). The maximum KE content is in the 10–20 km scale band in most of the eddy‐rich regions of the abyssal ocean. The seasonality of the KE spectrum and KE content inside the Arctic Ocean follow the seasonality of eddy activity and baroclinicity, with low values in spring and maxima in late summer to autumn, and the seasonal variation is stronger at the 70 m depth than the 400 m depth. The strong concentration of KE on the very small spatial scales warrants future studies on energy transfer between scales in the Arctic Ocean.
Coarse‐Grained Ripples Investigated by the Opportunity Rover on Meridiani Planum, Mars
Authors: Kozakiewicz J. , Dluzewski M. , Rotnicka J. , Sobucki M. , Michaels T. , Pilarska‐Mazurek M. , Krzemien K. , Nowak L. , Olszewski R. , Frodyma N. , Podbielska A. , Choromanski K.
Published: March 2024

Aeolian coarse‐grained ripples have been found in all regions investigated by Mars rovers: Meridiani Planum, Gusev crater, Gale crater, and Jezero crater. Therefore, it can be assumed that coarse‐grained ripples are one of the most common landforms on Mars. Studying their formation and evolution gives us the opportunity to determine past and current wind patterns. They are also crucial for understanding the formation and evolution of larger aeolian bedforms. Of all locations studied in situ on Mars, coarse‐grained ripples in extensive (∼100 km2) ripple fields were found only on Meridiani Planum. As coarse‐grained ripples on Mars are not well characterized in the literature, in this work, the morphometry, morphology, spatial distribution, and orientation of coarse‐grained ripples investigated along the 45 km long traverse of the Opportunity rover were analyzed. The obtained results allowed for a more precise definition of coarse‐grained ripples and for distinguishing three classes of coarse‐grained ripples on Meridiani Planum: small, medium, and large. The coarse‐grained ripple activity on Meridiani Planum is now limited due to low material supply, and the relatively strong induration of the ripple surfaces. Even though most of the coarse‐grained ripples on Meridiani Planum were formed thousands of years ago, some smaller coarse‐grained ripples were formed by modern winds.
A Tale of Two Catchments: Causality Analysis and Isotope Systematics Reveal Mountainous Watershed Traits That Regulate the Retention and Release of Nitrogen
Authors: Bouskill N. J. , Newcomer M. , Carroll R. W. H. , Beutler C. , Bill M. , Brown W. S. , Conrad M. , Dong W. S. , Falco N. , Maavara T. , Newman A. , Sorensen P. O. , Tokunaga T. K. , Wan J. , Wainwright H. , Zhu Q. , Brodie E. L. , Williams K. H.
Published: March 2024

Mountainous watersheds are characterized by variability in functional traits, including vegetation, topography, geology, and geomorphology, which determine nitrogen (N) retention, and release. Coal Creek and East River are two contrasting catchments within the Upper Colorado River Basin that differ markedly in total nitrate (NO3−) export. The East River has a diverse vegetation cover, and sinuous floodplains, and is underlain by N‐rich marine shale. At 0.21 ± 0.14 kg ha−1 yr−1, the East River exports ∼3.5 times more NO3− relative to the conifer‐dominated Coal Creek (0.06 ± 0.02 kg ha−1 yr−1). While this can partly be explained by the larger size of the East River, the distinct watershed traits of these two catchments imply different mechanisms controlling the aggregate N‐export signal. A causality analysis shows physical and biogenic processes were critical in determining NO3− export from the East River catchment. Stable isotope ratios of NO3− (δ15NNO3 and δ18ONO3) show the East River catchment is a strong hotspot for biogeochemical processing of NO3− at the hillslope soil‐saprolite. By contrast, the conifer‐dominated Coal Creek retained nearly all atmospherically deposited NO3−, and its export was controlled by catchment hydrological traits (i.e., snowmelt periods and water table depth). The conservative N‐cycle within Coal Creek is likely due to the abundance of conifer trees, and smaller riparian regions, retaining more NO3− overall and reduced processing prior to export. This study highlights the value of integrating isotope systematics to link watershed functional traits to mechanisms of watershed element retention and release.
Experimental Whole‐Ecosystem Warming Enables Novel Estimation of Snow Cover and Depth Sensitivities to Temperature, and Quantification of the Snow‐Albedo Feedback Effect
Authors: Richardson Andrew D. , Schädel Christina , Westergaard‐Nielsen Andreas , Novick Kimberly A. , Basler David , Phillips Jana R. , Krassovski Misha B. , Warren Jeffrey M. , Sebestyen Stephen D. , Hanson Paul J.
Published: March 2024

Climate change is reducing the amount, duration, and extent of snow across high‐latitude ecosystems. But, in landscapes where persistent winter snow cover develops, experimental platforms to specifically investigate interactions between warming and changes in snowpack, and impacts on ecosystem processes, have been lacking. We leveraged a whole‐ecosystem warming experiment in a boreal peatland forest to quantify how snow duration, depth, and fractional cover vary with warming of up to +9°C. We found that every snow‐related quantity we examined declined precipitously as the amount of warming increased. The importance of deep, continuous snow cover for moderating shallow soil temperature is highlighted by an increase in soil temperature variance and the frequency of short‐duration freeze‐thaw cycles in the warmer plots. We used a paired‐plot approach to estimate the magnitude of the snow‐albedo feedback effect, and demonstrate that albedo‐driven warming linked to reduced snow cover varies between December (+0.4°C increase in maximum air temperature) and March (+1.2°C increase) because of differences in insolation. Overall, results show that even modest future warming will have profound impacts on northern winters and cold‐season ecosystem processes. Plot‐level data from this warming experiment, and emergent relationships between warming and quantities related to snow cover and duration, could be of enormous value for testing and improving the representation of snow processes in simulation models, especially under future climate scenarios that are outside of the range of historically observed variability.
The Impact of the Bohemian Spur on the Cooling and Exhumation Pattern of the Eastern Alpine Wedge of the European Alps
Authors: Heberer Bianca , Salcher Bernhard C. , Tari Gabor , Wessely Godfrid , Dunkl István , Sachsenhofer Reinhard F. , Wagreich Michael , von Hagke Christoph
Published: March 2024

Fold and thrust belt architecture may be influenced by basement geometry of the downgoing plate. This influence is notoriously difficult to assess due to a common lack of subsurface constraints and low resolution of exhumation estimates in space and time. The Bohemian Spur is a basement high at the transition from the Alps to the Carpathians. It coincides with narrowing of the foreland basin and an orogen‐scale change of strike. Its location in one of the best‐studied orogens in the world makes it an ideal case for understanding how basement topography influences fold and thrust belt tectonics. However, since thermochronological studies were mainly focused on the core of the Alps, timing and amount of exhumation remain poorly constrained in these peripheral parts of the orogen. We present new apatite (U‐Th)/He and fission track data from the wedge above the Bohemian Spur. Thermally reset ages monitor a so far un(der)appreciated phase of prominent Late Oligocene to Miocene cooling, associated with crustal thickening, uplift and erosion during wedge propagation. Pronounced exhumation on the order of 3–4.5 km can be related to basement steps beneath the advancing wedge. The spur acted as a buttress for foreland‐propagating thrusting, pinning deformation and nucleating antiformal stacking and duplexing and thus exhumation above it. We illustrate how along‐ and across‐strike changes of sub‐detachment topography impact wedge propagation and control fold and thrust belt geometries. The buttressing effect accounts for most of the exhumation, while deep‐seated slab dynamics are of subordinate importance for wedge uplift.
Role of Lakes, Flood, and Low Flow Events in Modifying Catchment‐Scale DOC:TN:TP Stoichiometry and Export
Authors: Fasching Christina , Boodoo Kyle S. , Yao Huaxia , Rusak James A. , Xenopoulos Marguerite A.
Published: March 2024

The balance of organic carbon (OC), nitrogen (N) and phosphorus (P) plays a crucial role in determining the processing, retention, and movement of these solutes across the aquatic continuum. Floods and droughts can significantly alter the quantity and ratios of OC:N:P export within inland waters, but how these ratios change, and are coupled within watersheds that integrate rivers and lakes, is not well known. We investigated the stoichiometry and export of dissolved organic carbon (DOC), total N (TN) and total P (TP) in two lake watersheds (10 inflows, 2 outflows) in the southern Boreal Shield over a 37‐year period. Although DOC, TN, and TP concentration behaved similarly, DOC:TN:TP ratios varied seasonally, strongly modulated by stream discharge. DOC:TN, DOC:TP and TN:TP export initially increased rapidly with increasing discharge, peaking at 10%–20% exceedance of the annual discharge for DOC:TP and TN:TP ratios, indicating a rapid depletion of catchment OC sources. Both flood and low flow events resulted in lower DOC:TN and lower DOC:TP export—thereby increasing the relative contributions of stream TN and TP. Consequently, elevated annual discharge coupled with infrequent but high floods and periods of low flow events increased the contributions of TN and TP relative to DOC. Overall, the lakes retained DOC, while increasing TN relative to TP. Nonetheless, the flow regime played a role in modulating nutrient retention in the lakes, likely due to changes in residence time, and the interplay of physical, photochemical, and biological degradation processes.