bluuebunny/crossref_metadata_2025 huggingface dataset:
Unveiling the persistence of meteorological drought in Iraq: a comprehensive spatiotemporal analysis
Authors: Hatem Israa , Alwan Imzahim A. , Ziboon Abdul Razzak T. , Kuriqi Alban
Published: August 2024

Droughts, stemming from prolonged periods of scarce precipitation, lead to significant economic and societal consequences. Iraq has recurrently experienced the impact of severe droughts. This study assessed meteorological drought over Iraq, employing the Standardized Precipitation Index (SPI) on 12-month time scales from 2000 to 2022. The SPI values were calculated for 27 meteorological stations over Iraq based on the monthly datasets. The analysis of the SPI highlighted that the years 2000, 2008, 2009, 2010, 2012, 2018, and 2022 stood out as the driest in Iraq from 2000 to 2022. Notably, 2022 emerged as a particularly severe drought year, with the Ramadi weather station recording the maximum SPI value at -3.48. Different time scales in the analysis provided a more precise depiction of drought severity and frequency in Iraq. Namely, the findings resulting from this study offer a nuanced understanding of the magnitude, intensity, frequency, and duration of drought events in Iraq. This nuanced approach equips stakeholders with valuable insights for implementing more cost-effective mitigation and adaptation measures. This study contributes crucial information for understanding and addressing droughts challenges in Iraq. The comprehensive analysis aids in formulating targeted strategies to alleviate the impact of droughts on people and ecosystems.
Mapping the composite nature of clay matrix in mudstones: integrated micromechanics profiling by high-throughput nanoindentation and data analysis
Authors: Shi Xiangyun , Misch David , Zak Stanislav , Cordill Megan , Kiener Daniel
Published: August 2024

Mudstones and shales serve as natural barrier rocks in various geoenergy applications. Although many studies have investigated their mechanical properties, characterizing these parameters at the microscale remains challenging due to their fine-grained nature and susceptibility to microstructural damage introduced during sample preparation. This study aims to investigate the micromechanical properties of clay matrix composite in mudstones by combining high-speed nanoindentation mapping and machine learning data analysis. The nanoindentation approach effectively captured the heterogeneity in high-resolution mechanical property maps. Utilizing machine learning-based k-means clustering, the mechanical characteristics of matrix clay, brittle minerals, as well as measurements on grain boundaries and structural discontinuities (e.g., cracks) were successfully distinguished. The classification results were validated through correlation with broad ion beam-scanning electron microscopy images. The resulting average reduced elastic modulus (Er) and hardness (H) values for the clay matrix were determined to be 16.2 ± 6.2 and 0.5 ± 0.5 GPa, respectively, showing consistency across different test settings and indenter tips. Furthermore, the sensitivity of indentation measurements to various factors was investigated, revealing limited sensitivity to indentation depth and tip geometry (when comparing Cube corner and Berkovich tip in a small range of indentation depth variations), but decreased stability at lower loading rates. Box counting and bootstrapping methods were applied to assess the representativeness of parameters determined for the clay matrix. A relatively small dataset (indentation number = 60) is needed to achieve representativeness, while the main challenges is to cover a representative mapping area for clay matrix characterization. Overall, this study demonstrates the feasibility of high-speed nanoindentation mapping combined with data analysis for micromechanical characterization of the clay matrix in mudstones, paving the way for efficient analysis of similar fine-grained sedimentary rocks.
The Association Between Vitamin D and Executive Functions in Healthy Young- and Middle-Aged Adults: A Scoping Review
Authors: Redlich Dennis , Schommer Leonard , Krüger Karsten , Raab Markus
Published: August 2024

Peak performances in different life domains are often achieved by healthy young- or middle-aged adults and are partly based on their executive functions. The extensive literature on older or non-healthy populations suggests an adequate availability of vitamin D as essential for good executive functioning. However, for healthy young- or middle-aged populations, the association between vitamin D levels and executive functions is not well understood. To test whether previous findings generalize to healthy young- or middle-aged participants, we conducted a scoping review to systematically map the existing literature on the association between vitamin D levels and executive functions. Literature searches of three databases were performed identifying seven studies that met the inclusion criteria. Results indicate mixed findings for the relationship between vitamin D and the three core executive functions cognitive flexibility, response inhibition, and working memory. Thus, this scoping review indicates a rather unsystematic impact of varying vitamin D levels or supplements on executive functions among healthy young- or middle-aged populations and we argue for more systematic investigations in the future.
Anticorrosive and Superhydrophobic Surface on Ti–6Al–4V Through One-Step Anodic Etching
Authors: Weng Zhankun , Niu Haobo , Wang Rui , Zhong Huazhen , Wang Shenzhi , Liu Ri , Zhu Xiaona , Wang Bowei , Li Tao , Wang Wei , Xu Hongmei , Wang Zuobin
Published: August 2024

Herein, an anticorrosive and hydrophobic surface for Ti–6Al–4V was prepared through one-step anodic etching. The results showed that wettability was adjusted by current density and etching time. In particular, the maximum water contact angle (WCA) reached ~ 160.9° at a current density of 0.25 A cm−2 for 420 s. Energy dispersive spectroscopy and X-ray photoelectron spectroscopy showed the existence of spontaneous surface passivation, which was also verified by Tafel curves. In addition, Ecorr and icorr exhibited good anticorrosion properties on the surface of the Ti–6Al–4V after anodic etching. Furthermore, the change in surface adhesion was consistent with the change in the WCA after anodic etching. In conclusion, the one-step anodic etching can provide a convenient way to realize anticorrosion and superhydrophobic Ti–6Al–4V surface.
Diversity, stand and population structure of riparian woody species in two contrasting land use types in the distal Okavango Delta, Northwestern Botswana
Authors: Tsheboeng Gaolathe , Teketay Demel , Murray-Hudson Mike , Kashe Keotshephile , Mmusi Mmusi , Madome Joseph
Published: August 2024

Land use change threatens the integrity of riparian woodland vegetation. The aim of this study was to investigate the diversity and population structure of riparian plant species in protected and communal areas. A total of 71 transects were sampled from each of the protected and communal areas. Total species richness recorded was 36 and 38 in communal and protected areas, respectively. Species diversity was significantly (p < 0.05) higher in the protected than communal areas. Vachellia tortilis (communal areas) and Croton megalobotrys (both areas) showed a reverse J shaped pattern with more individuals in the lower diameter size classes than in the large ones. Dichrostachys cinerea (both areas), Ziziphus mucronata (communal areas), Combretum imberbe (protected areas), C. hereroense (protected areas), Berchemia discolor (protected areas) and Vachellia erioloba (communal areas) showed a reverse-J distribution pattern, but with missing size classes. Philenoptera violacea (protected areas) was characterized by a bell-shaped distribution with more individuals in the middle size classes than in the lower and upper ones while Combretum hereroense, C. imberbe and B. discolor were characterized by irregular population structure in communal areas. Croton megalobotrys, D. cinerea, C. imberbe, C. hereroense, Z. mucronata, B. discolor and S. erubescens had higher Important Value Indices (IVIs) in protected than communal areas. Comparatively, Vachellia tortilis, P. violacea and V. erioloba had higher IVIs in communal than protected areas. We recommended that species with J-shaped population structure and those with only one size class be protected to enable them to attain healthy population structures.
Don Quixote and the Green Army: Lessons from Australian Environmental Workfare
Authors: Cooper Jai
Published: August 2024

Australia’s unique history of national environmental youth workfare programs over three decades offers insight into youth work responses to climate change. Drawing upon Bourdieu’s use of ‘hysteresis’ and the ‘Don Quixote Effect’, this paper presents three key findings from research conducted in the wake of the most recent incarnation of these programs, the Australian Government’s Green Army. As the final Green Army projects were being delivered, interviews and focus groups were independently conducted with former team members and supervisors who had exited the program and its predecessors. The Green Army was presented for political purposes as action against climate change despite no specific climate mitigation outcomes being identified. Supervisors, predominantly trained in the environmental sciences, given charge of teams of young workers, reported the double binds from the competing fields of ecological work and social work. Team members, faced with resistance to their efforts, reconciled their situation with a ‘double language of disinterest’. The analysis of their accounts illuminates potential challenges facing the future for young people and for youth work.
Significance of millets for food and nutritional security—an overview
Authors: Sanjay Kumar Thillaigovindan , Nageswari Raman , Somasundaram Selvaraj , Anantharaju Pokkaru , Baskar Murugaiyan , Ramesh Thanakkan , Rathika Selvaraj , Vanniarajan Chockalingam , Subrahmaniyan Kasirajan
Published: August 2024

Millets are an important traditional food known for their dietary diversity. They play a key role in ensuring human health and well-being. Millets, which are small-seeded grains cultivated widely in various areas of the world, have emerged as significant contributors to this paradigm shift. They are nutrition powerhouses, that boast raised levels of dietary fibre, protein, vitamins, and minerals. Since they are gluten free, those with celiac disease may utilize them and serve as alternatives to wheat products. The promotion of these grains as a staple food holds significant promise for facing the global challenges of malnutrition, food insecurity, and environmental degradation. Moreover, millets contain bio-active compounds like flavonoids, lignin, phenolic acids reduce inflammation and serve as antioxidants. Millets have positive health benefits related to blood sugar, cardiovascular disease and obesity, and the gastrointestine. This article provides an overview of the functional role of millets as promising food for human health.
Tribute to Michel E. Safar (1937–2024): A Groundbreaker in the Concept of Hypertension
Authors: Lacolley Patrick , Struijker-Boudier Harry , Regnault Veronique , Barbier Moyra
Published: August 2024

The authors present a short review of the personality, clinical and scientific contributions of a distinguished member of our Academy, the Artery Society and so many others, where he contributed landmark advances in many fields of arterial function and cardiovascular risk. The Editorial Board of the Artery Research Journal and the Executive Committee of the Artery Society present their due respects to Prof. Michel Safar.
“Vivre en paix et en bonne intelligence avec les princes locaux” in Senegambia in the Age of Slave Economy: Diplomatic Treaties, Trade, Conflicts, and Peace in Interaction (1679–1815)
Authors: Sene Cheikh
Published: August 2024

The violent and competitive context in which trade relations between the states of Senegambia and Europeans evolved required moments of calm and stability, which were decisive and important factors in the cohabitation of trade actors. Diplomacy was a fundamental political lever for European trade in Senegambia. It had become a major stake in the daily lives of the actors. Diplomacy was generally reserved for field actors from different political cultures and with different political and economic ambitions. Diplomacy took the form of negotiations, and took the form of simple agreements of principle, notably in the context of palavers, or the conclusion of trade and peace treaties. The aim of diplomacy, for example, was to establish strong, peaceful commercial relations between trade players and to regularize the tax system, which was the fundamental basis of trade and the expression of the sovereignty of local chiefs towards the Europeans.
Shear-induced depinning of thin droplets on rough substrates
Authors: Mhatre Ninad V. , Kumar Satish
Published: August 2024

Depinning of liquid droplets on substrates by flow of a surrounding immiscible fluid is central to applications such as cross-flow microemulsification, oil recovery and waste cleanup. Surface roughness, either natural or engineered, can cause droplet pinning, so it is of both fundamental and practical interest to determine the flow strength of the surrounding fluid required for droplet depinning on rough substrates. Here, we develop a lubrication-theory-based model for droplet depinning on a substrate with topographical defects by flow of a surrounding immiscible fluid. The droplet and surrounding fluid are in a rectangular channel, a pressure gradient is imposed to drive flow and the defects are modelled as Gaussian-shaped bumps. Using a precursor-film/disjoining-pressure approach to capture contact-line motion, a nonlinear evolution equation is derived describing the droplet thickness as a function of distance along the channel and time. Numerical solutions of the evolution equation are used to investigate how the critical pressure gradient for droplet depinning depends on the viscosity ratio, surface wettability and droplet volume. Simple analytical models are able to account for many of the features observed in the numerical simulations. The influence of defect height is also investigated, and it is found that, when the maximum defect slope is larger than the receding contact angle of the droplet, smaller residual droplets are left behind at the defect after the original droplet depins and slides away. The model presented here yields considerably more information than commonly used models based on simple force balances, and provides a framework that can readily be extended to study more complicated situations involving chemical heterogeneity and three-dimensional effects.
Inertial particle focusing in fluid flow through spiral ducts: dynamics, tipping phenomena and particle separation
Authors: Valani Rahil N. , Harding Brendan , Stokes Yvonne M.
Published: August 2024

Small finite-size particles suspended in fluid flow through an enclosed curved duct can focus to points or periodic orbits in the two-dimensional duct cross-section. This particle focusing is due to a balance between inertial lift forces arising from axial flow and drag forces arising from cross-sectional vortices. The inertial particle focusing phenomenon has been exploited in various industrial and medical applications to passively separate particles by size using purely hydrodynamic effects. A fixed size particle in a circular duct with a uniform rectangular cross-section can have a variety of particle attractors, such as stable nodes/spirals or limit cycles, depending on the radius of curvature of the duct. Bifurcations occur at different radii of curvature, such as pitchfork, saddle-node and saddle-node infinite period (SNIPER), which result in variations in the location, number and nature of these particle attractors. By using a quasi-steady approximation, we extend the theoretical model of Harding et al. (J. Fluid Mech., vol. 875, 2019, pp. 1–43) developed for the particle dynamics in circular ducts to spiral duct geometries with slowly varying curvature, and numerically explore the particle dynamics within. Bifurcations of particle attractors with respect to radius of curvature can be traversed within spiral ducts and give rise to a rich nonlinear particle dynamics and various types of tipping phenomena, such as bifurcation-induced tipping (B-tipping), rate-induced tipping (R-tipping) and a combination of both, which we explore in detail. We discuss implications of these unsteady dynamical behaviours for particle separation and propose novel mechanisms to separate particles by size in a non-equilibrium manner.
Resonant standing surface waves excited by an oscillating cylinder in a narrow rectangular cavity
Authors: Mogilevskiy Evgeny , Kalenko S. , Zemach E. , Shemer L.
Published: August 2024

Resonant standing waves excited on the water surface in a deep narrow rectangular cavity by a fully immersed cylinder harmonically oscillating in the vertical direction are studied theoretically and experimentally. The effect of the finite wavemaker size is considered in the framework of the potential two-dimensional flow theory. Nonlinearities and weak dissipation at solid surfaces are accounted for. The spatio-temporal structure of the waves in the presence of detuning between the forcing and the natural frequency of the system is analysed. The variation of the surface shape in space and time studied in experiments supports the assumption of two-dimensional flow. The finite size of the wavemaker causes a downshift of the effective resonant frequency of the cavity; this effect is enhanced by the nonlinearity. For small amplitude waves, the surface elevation evolution in time is decomposed into the sum of the time-periodic function, corresponding to the forcing frequency, and its second harmonic; the shape of the wavenumber spectra of these components depends on the forcing frequency. For larger wave amplitudes, additional peaks in the frequency spectrum appear. The theoretical predictions are compared with the experimental results.
Dynamics of weighted flexible ribbons in a uniform flow
Authors: Liu Kui , Huang Haibo
Published: August 2024

This study explores the dynamics of flexible ribbons with an added weight

$G$

at the tail in uniform flow, considering key parameters like inflow Reynolds number (

$Re_u$

), mass ratio (

$M_t$

) and aspect ratio (

${A{\kern-4pt}R}$

). For two-dimensional ribbons, a simplified theoretical model accurately predicts equilibrium configurations and forces. Inspired by Barois & De Langre (J. Fluid Mech., vol. 735, 2013, R2), we introduce an important control parameter (

$C_G$

) that effectively collapses normalized forces and angle data. Vortex-induced vibration is observed, and Strouhal number (

$St$

) scaling laws with

$C_G$

are identified. In three-dimensional scenarios, the model effectively predicts lift, but its accuracy in predicting drag is limited to situations with small

$Re_u$

values. The flow along the side edges mitigates pressure differences, thereby suppressing vibration and uplift, particularly noticeable in the case of narrow ribbons. This study offers new insights into the dynamics of flexible bodies in uniform flow.
Cracking of submerged beds
Authors: Bhadra Satyanu , Sane Anit , Ghosh Akash , Ghosh Shankar , Sahu Kirti Chandra
Published: August 2024

We investigate the phenomena of crater formation and gas release caused by projectile impact on underwater beds, which occurs in many natural, geophysical and industrial applications. The bed in our experiment is constructed of hydrophobic particles, which trap a substantial amount of air in the pores of the bed. In contrast to dry beds, the air–water interface in a submerged bed generates a granular skin that provides rigidity to the medium by producing skin over the bulk. The projectile's energy is used to reorganize the grains, which causes the skin to crack, allowing the trapped air to escape. The morphology of the craters as a function of impact energy in submerged beds exhibits different scaling laws than what is known for dry beds. This phenomenon is attributed to the contact line motion on the hydrophobic fractal-like surface of submerged grains. The volume of the gas released is a function of multiple factors, chiefly the velocity of the projectile, depth of the bed and depth of the water column.
Mechanism of vortex oscillation around a hemisphere–cylinder body
Authors: Wang Zhou-Yang , Ma Bao-Feng
Published: August 2024

Previous studies have shown that low-frequency vortex oscillations occur around a hemisphere–cylinder body at different angles of attack, but the underlying mechanism is still unclear. In this study, we examine the origin of the vortex oscillation using numerical simulations and global linear stability analysis. The vortex oscillation is reproduced using numerical simulations, and the oscillatory modes are computed through dynamic mode decomposition (DMD). We obtain the base flow through a selective frequency damping method, which exhibits a pair of steady leeward vortices over the body. The four unstable modes are computed using a modified Arnoldi iteration. The antisymmetric mode with a Strouhal number of 0.105 is discovered to be responsible for the alternate oscillation of the vortex pair, and the mode with a Strouhal number of 0.220 corresponds to the in-phase vortex oscillation. Their frequencies have good agreement with the modes of DMD. The other two unstable modes with higher frequencies, one antisymmetric and one symmetric, are harmonic frequencies of the above two modes. The study conclusively verifies that the vortex oscillation over a hemisphere–cylinder body originates from a global flow instability.
Instability and transition control by steady local blowing/suction in a hypersonic boundary layer
Authors: Zhuang Guo-Hui , Wan Zhen-Hua , Liu Nan-Sheng , Sun De-Jun , Lu Xi-Yun
Published: August 2024

The efficacy of steady large-amplitude blowing/suction on instability and transition control for a hypersonic flat plate boundary layer with Mach number 5.86 is investigated systematically. The influence of the blowing/suction flux and amplitude on instability is examined through direct numerical simulation and resolvent analysis. When a relatively small flux is used, the two-dimensional instability critical frequency that distinguishes the promotion/suppression mode effect closely aligns with the synchronisation frequency. For the oblique wave, as the spanwise wavenumber increases, the suppression effects would become weaker and the mode suppression bandwidth diminishes/increases in general in the blowing/suction control. Increasing the blowing/suction flux can effectively broaden the frequency bandwidth of disturbance suppression. The influence of amplitude on disturbance suppression is weak in a scenario of constant flux. To gain a deeper insight into disturbance suppression mechanism, momentum potential theory (MPT) and kinetic energy budget analysis are further employed in analysing disturbance evolution with and without control. When the disturbance is suppressed, the blowing induces the transport of certain acoustic components along the compression wave out of the boundary layer, whereas the suction does not. The velocity fluctuations are derived from the momentum fluctuations of the MPT. Compared with the momentum fluctuations, the evolutions indicated by each component's velocity fluctuations greatly facilitate the investigations of the acoustic nature of the second mode. The rapid variation of disturbance amplitude near the blowing is caused by the oscillations of the acoustic component and phase speed differences between vortical and thermal components. Kinetic energy budget analysis is performed to address the non-parallel effect of the boundary layer introduced by blowing/suction, which tends to suppress disturbances near the blowing. Moreover, viscous effects leading to energy dissipation are identified to be stronger in regions where the boundary layer is rapidly thickening. Finally, it is demonstrated that a flat plate boundary layer transition triggered by a random disturbance can be delayed by a blowing/suction combination control. The resolvent analysis further demonstrates that disturbances with frequencies that dominate the early transition stage are dampened in the controlled base flow.
“If your ox does not pull, what are you going to do?”: Persistent Violence in South Africa’s Deep-Level Gold Mines and Its Contribution to the 1922 Rand Rebellion
Authors: Higginson John Edward
Published: August 2024

The 1922 Rand Rebellion was the only instance of worker protest in the twentieth century in which a modern state used tanks and military airplanes, as well as mounted infantry, to suppress striking workers. These circumstances were unprecedented in their own time and for most of the century. The compressed and intensely violent rebellion of twenty thousand white mineworkers in South Africa’s gold mines had several overlapping features. Within a matter of days—from 6 to 12 March—it went from a general strike to a racial pogrom and insurrection against the government of Prime Minister Jan Smuts. Throughout all these twists and turns, the battle standard remained, “Workers of the world unite and fight for a White South Africa!” Race and violence were integral features of South Africa’s industrial history, but they do not explain the moments when discrete groups of people chose to use them as weapons or bargaining tools. At the close of the First World War, for instance, South Africa’s white mine workers demanded a more comprehensive distribution of the privileges of white supremacy, but in a manner that was both violent and contentious. Consequently, South Africa’s immediate postwar period became one of the most violent moments in its history.
Structural Controls on Fault Slip Models of the 6 February 2023 Kahramanmaraş, Türkiye Earthquake Doublet With Finite Element Analyses
Authors: Tung Sui , Sippl Christian , Shirzaei Manoochehr , Taymaz Tuncay , Masterlark Timothy , Medved Irina
Published: August 2024

Two major earthquakes of Mw7.8 and Mw7.5 ruptured the Southern East Anatolian Fault (SEAF) and the Savrun‐Çardak‐Sürgü fault (SCSF), devastating southeast Türkiye and northwest Syria on 6 February 2023. We adopt innovative nonlinear and linear approaches to analyze the coseismic ground displacements and estimate the complex slip geometry. Unlike conventional analytical solutions that simplify crust heterogeneity, finite‐element fault models invert the displacement data and simulate the dual‐fault geometry with non‐uniformly distributed shallow crustal materials. Our results suggest the west‐dipping SEAF and north‐dipping SCSF accommodate earthquake slips of >10 m. Their respective slip distributions and proximal aftershocks correlate spatially with local seismic velocity anomalies (i.e., ΔVp and ΔVs), which implies differences in structural control along these two faults and provides insights into assessing the seismic hazard of mixed incipient‐mature fault systems.
Circulation and Hydrography in the Northwestern Barents Sea: Insights From Recent Observations and Historical Data (1950–2022)
Authors: Kolås Eivind H. , Baumann Till M. , Skogseth Ragnheid , Koenig Zoe , Fer Ilker
Published: August 2024

The Barents Sea is one of the main pathways for warm and saline Atlantic Water (AW) entering the Arctic Ocean. It is an important region where water mass transformation and dense‐water production contribute to the Atlantic meridional overturning circulation. Here, we present data from three cruises and nine glider missions conducted between 2019 and 2022 in the northwestern Barents Sea, and compare them with historical data collected between 1950 and 2009. We present circulation pathways, hydrography and volume transports of Atlantic‐ and Arctic‐origin waters. Our observations show that 0.9 ± 0.1 Sv (1 Sv = 106 m3 s−1) of Atlantic‐origin water reaches the Polar Front (PF) region before splitting into several branches and eventually subducting beneath Polar Water (PW). The amount of Atlantic‐origin water stored in the Olga Basin north of the PF is controlled by the density difference between AW and PW, and reached a maximum in the 90s when PW was particularly fresh. In the recent period from 2019 to 2022, the inflow of AW into the Barents Sea freshened by up to 0.1 g kg−1 compared to previous decades. This led to a reduction in the production of dense water, an increased temperature gradient across the PF, and a reduced poleward transport of warm water.
Multiple Slabs and Complex Mantle Flows in the Molucca Sea Subduction Zone
Authors: Yuan Tianmeng , Wang Zewei , Zhao Dapeng , Gao Rui , Chen Xiaofei
Published: August 2024

The Molucca Sea subduction zone is unique for its active divergent double‐subducted slab located in the north of the Java and Banda subduction zones. The spatial proximity of these subduction zones would cause a complex mantle flow field. To clarify the mantle dynamics, here we present P‐wave tilting‐axis anisotropic tomography obtained by inverting a large number of local and teleseismic travel‐time data recorded at 254 seismic stations in eastern Southeast Asia. Our results suggest that the mantle structure and dynamics of the western Molucca Sea subduction zone may be remotely controlled by the Java and Banda subduction zones. Mantle convection in the big mantle wedge west of the Molucca Sea subduction zone is possibly influenced by east‐west mantle flow associated with compression of the Indo‐Australian slab as well as north‐south mantle flow related to rollback of the Indo‐Australian slab. In contrast, the eastern Molucca Sea subduction zone is virtually unaffected by other subduction zones, probably due to the ongoing slab subduction there.
Assessing the Sources of the O+ in the Plasma Sheet
Authors: Liao J. , Kistler L. M. , Mouikis C. G. , Fuselier S. A. , Hedlund M.
Published: August 2024

To study the average contributions of the cusp outflow through the lobes and of the nightside auroral outflow to the O+ in the plasma sheet (PS), we performed a statistical study of tailward streaming O+ in the lobes, plasma sheet boundary layer|the plasma sheet boundary layer (PSBL) and the PS, using MMS/Hot Plasma Composition Analyzer (HPCA) data from 2017 to 2020. Similar spatial patterns illustrate the entry of cusp‐origin O+ from the lobes to the PS through the PSBL. There is an YGSM‐dependent energy pattern for the lobe O+, with low‐energy O+ streaming closer to the tail center and high energy (1–3 keV) O+ streaming near the flanks. Low energy (1–100 eV) O+ from the nightside auroral oval is identified in the near‐Earth PSBL/PS with high‐density (>0.02 cm−3), and energetic (>3 keV) streaming O+ with similar density (∼0.013 cm−3) is observed further out on the duskside of the PSBL/PS. The rest of the nightside auroral O+ in the PSBL is mixed with O+ coming in from the lobe, making it difficult to distinguish the source. We estimated the contributions of the different sources of H+ and O+ ions through the PS between 7 and 17 RE, using estimates from this work and data extracted from previous studies. We conclude that, during quiet times, the majority of the near‐Earth PS H+ are from the cusps, the polar wind and Earthward convection from the distant tail. Similarly, while the O+ in the same region has a mixed source, cusp origin outflow provides the highest contribution.
Carbon Monoxide in the Marine Atmosphere and Seawater: Spatiotemporal Distribution and Photobiogeochemical Cycling
Authors: Yang Lin , Gong Chun‐Yan , Mo Xiang‐Jie , Zhang Jing , Yang Bin , Yang Gui‐Peng
Published: August 2024

Carbon monoxide (CO) plays a vital role in the biochemical processes of marine microorganisms, climate regulation, and global carbon cycle. In this study, seasonal and spatial variations of CO and oceanographic factors influencing these variations were investigated in the East China Sea (ECS) during two cruises from 16 to 30 May 2020 and from 8 to 30 October 2021. ECS was as a net source of atmospheric CO in both spring and autumn. The average values of seawater CO concentrations ([CO]surf), atmospheric CO mixing ratio ([CO]atm) and sea‐to‐air flux of CO were 2.22 ± 0.47 nmol L−1 and 0.97 ± 0.86 nmol L−1, 182.8 ± 71.8 ppbv and 102.7 ± 38.8 ppbv, 96.14 ± 25.82 nmol m−2 hr−1 and 31.96 ± 35.61 nmol m−2 hr−1 in spring and autumn, respectively. A steady‐state model was used to estimate the biogeochemical cycling rates of [CO]atm over the ECS. The effect of CO sea‐to‐air fluxes on atmospheric ·OH concentration was likely decreased from spring to autumn. Photoirradiation experiments further showed that the actual contributions of ultraviolet radiation and photosynthetically active radiation to CO photoproduction in the surface waters were 72.2% ± 13.8% and 27.8% ± 13.8%, respectively. The sea‐to‐air fluxes of CO in autumn were 5.15 μmol m−2 day−1 lower than in spring, which were due to larger bacterial consumption and lower [CO]surf in autumn in the ECS. Further, this study is expected to improve our understanding of the biogeochemical processes of CO in the eastern marginal seas of China.
Identification of interactions between genetic risk scores and dietary patterns for personalized prevention of kidney dysfunction in a population-based cohort
Authors: Jang Min-Jae , Tan Li-Juan , Park Min Young , Shin Sangah , Kim Jun-Mo
Published: August 2024

Background & Aim

Chronic kidney disease (CKD) is a heterogeneous disorder that affects the kidney structure and function. This study investigated the effect of the interaction between genetic factors and dietary pattern on kidney dysfunction in Korean adults.

Methods

Baseline data were obtained from the Ansan and Ansung Study of the Korean Genome and Epidemiology Study involving 8230 participants aged 40–69 years. Kidney dysfunction was defined as an estimated glomerular filtration rate < 90 mL/minute/1.73 m2. Genomic DNAs genotyped on the Affymetrix® Genome-Wide Human SNP array 5.0 were isolated from peripheral blood. A genome-wide association study using a generalized linear model was performed on 1,590,162 single-nucleotide polymorphisms (SNPs). To select significant SNPs, the threshold criterion was set at P-value < 5 × 10−8. Linkage disequilibrium clumping was performed based on the R2 value, and 94 SNPs had a significant effect. Participants were divided into two groups based on their generic risk score (GRS): the low-GR group had GRS > 0, while the high-GR group had GRS ≤ 0.

Results

Three distinct dietary patterns were extracted, namely, the “prudent pattern,” “flour-based and animal food pattern,” and “white rice pattern,” to analyze the effect of dietary pattern on kidney function. In the “flour-based and animal food pattern,” higher pattern scores were associated with a higher prevalence of kidney dysfunction in both the low and high GR groups (P for trend < 0.0001 in the low-, high-GR groups of model 1; 0.0050 and 0.0065 in the low-, high-GR groups of model 2, respectively).

Conclusions

The results highlight a significant association between the ‘flour-based and animal food pattern’ and higher kidney dysfunction prevalence in individuals with both low and high GR. These findings suggest that personalized nutritional interventions based on GR profiles may become the basis for presenting GR-based individual dietary patterns for kidney dysfunction.
Microbial cell-free DNA-sequencing as an addition to conventional diagnostics in neonatal sepsis
Authors: Balks Julian , Grumaz Silke , Mazzitelli Sonia , Neder Ulrike , Lemloh Lotte , Melaku Tamene , Glaser Kirsten , Mueller Andreas , Kipfmueller Florian
Published: August 2024

Background

Bloodstream infections remain a challenge for neonatologists, as traditional culture-based methods are time-consuming and rely on adequate blood volume. Next-generation sequencing (NGS) offers an alternative, as it can identify microbial cell-free DNA (mcfDNA) in a small blood sample, providing rapid pathogen detection. This study aimed to assess the diagnostic performance of DISQVER®-NGS compared to blood cultures in neonatal patients with suspected sepsis.

Methods

In neonates with suspected sepsis, blood cultures and samples for NGS were prospectively collected. Patients were divided into four categories: 1) sepsis, blood culture positive, 2) clinical sepsis, culture negative, 3) suspected sepsis, 4) validation cohort.

Results

NGS detected bacterial, viral or fungal mcfDNA in 24 of 82 samples. Blood cultures were collected in 46 of 84 patients (15/46 positive). DISQVER® correctly identified pathogens in 9/15 patients with a positive blood culture, two with intrinsic resistance to their antibiotic regimen. In seven samples NGS reported the mcfDNA of bacteria that could have theoretically grown in culture but did not.

Conclusions

NGS may enhance sensitivity in sepsis diagnostics by detecting mcfDNA in neonates with suspected sepsis. Interpreting NGS results requires correlation with clinical data, laboratory values, and routine microbiological tests for a comprehensive understanding of the patient’s condition.

Impact

Conventional blood culture methods have limitations in accuracy and turnaround time.

The study aimed to investigate the diagnostic performance of the Next-Generation Sequencing method DISQVER® compared to traditional blood cultures in neonatal patients with suspected sepsis.

Our findings suggest that NGS has the potential to augment the precision of conventional diagnostic techniques, can lead to improved detection of pathogens and targeted treatment approaches in neonatal sepsis.

It is emphasized that further validation and integration with clinical and microbiological data are required to ensure optimal clinical utility.
Drug tolerant persister cell plasticity in cancer: a revolutionary strategy for more effective anticancer therapies
Authors: He Jun , Qiu Zejing , Fan Jingjing , Xie Xiaohong , Sheng Qinsong , Sui Xinbing
Published: August 2024

Non-genetic mechanisms have recently emerged as important drivers of anticancer drug resistance. Among these, the drug tolerant persister (DTP) cell phenotype is attracting more and more attention and giving a predominant non-genetic role in cancer therapy resistance. The DTP phenotype is characterized by a quiescent or slow-cell-cycle reversible state of the cancer cell subpopulation and inert specialization to stimuli, which tolerates anticancer drug exposure to some extent through the interaction of multiple underlying mechanisms and recovering growth and proliferation after drug withdrawal, ultimately leading to treatment resistance and cancer recurrence. Therefore, targeting DTP cells is anticipated to provide new treatment opportunities for cancer patients, although our current knowledge of these DTP cells in treatment resistance remains limited. In this review, we provide a comprehensive overview of the formation characteristics and underlying drug tolerant mechanisms of DTP cells, investigate the potential drugs for DTP (including preclinical drugs, novel use for old drugs, and natural products) based on different medicine models, and discuss the necessity and feasibility of anti-DTP therapy, related application forms, and future issues that will need to be addressed to advance this emerging field towards clinical applications. Nonetheless, understanding the novel functions of DTP cells may enable us to develop new more effective anticancer therapy and improve clinical outcomes for cancer patients.
Therapeutic advances of targeting receptor tyrosine kinases in cancer
Authors: Tomuleasa Ciprian , Tigu Adrian-Bogdan , Munteanu Raluca , Moldovan Cristian-Silviu , Kegyes David , Onaciu Anca , Gulei Diana , Ghiaur Gabriel , Einsele Hermann , Croce Carlo M.
Published: August 2024

Receptor tyrosine kinases (RTKs), a category of transmembrane receptors, have gained significant clinical attention in oncology due to their central role in cancer pathogenesis. Genetic alterations, including mutations, amplifications, and overexpression of certain RTKs, are critical in creating environments conducive to tumor development. Following their discovery, extensive research has revealed how RTK dysregulation contributes to oncogenesis, with many cancer subtypes showing dependency on aberrant RTK signaling for their proliferation, survival and progression. These findings paved the way for targeted therapies that aim to inhibit crucial biological pathways in cancer. As a result, RTKs have emerged as primary targets in anticancer therapeutic development. Over the past two decades, this has led to the synthesis and clinical validation of numerous small molecule tyrosine kinase inhibitors (TKIs), now effectively utilized in treating various cancer types. In this manuscript we aim to provide a comprehensive understanding of the RTKs in the context of cancer. We explored the various alterations and overexpression of specific receptors across different malignancies, with special attention dedicated to the examination of current RTK inhibitors, highlighting their role as potential targeted therapies. By integrating the latest research findings and clinical evidence, we seek to elucidate the pivotal role of RTKs in cancer biology and the therapeutic efficacy of RTK inhibition with promising treatment outcomes.
Cost-effectiveness of point of care smoking cessation interventions in oncology clinics
Authors: Mullen Kerri A. , Hurley Kelly , Hewitson Shelley , Scoville Joshua , Grant Alyssa , Thavorn Kednapa , Kumar Eshwar , Warren Graham W.
Published: August 2024

Background

We examined the cost-effectiveness of providing systematic smoking cessation interventions to oncology patients at point-of-care.

Methods

A decision analytic model was completed from the healthcare payer’s perspective and included all incident cancer cases involving patients who smoke in New Brunswick, Canada (n = 1040), cancer site stratifications, and risks of mortality, continued smoking, and cancer treatment failure over one year. Usual care (no cessation support) was compared to the standard Ottawa Model for Smoking Cessation (OMSC) intervention, and to OMSC plus unlimited cost-free stop smoking medication (OMSC + SSM), including nicotine replacement therapy, varenicline, or bupropion. Primary outcomes were incremental cost per quit (ICQ) and incremental cost per cancer treatment failure avoided (ICTFA).

Results

The ICQ was $C143 and ICTFA $C1193 for standard OMSC. The ICQ was $C503 and ICTFA was $C5952 for OMSC + SSM. The number needed to treat (NNT) to produce one quit was 9 for standard OMSC and 4 for OMSC + SSM, and the NNT to avoid one first-line treatment failure was 78 for OMSC and 45 for OMSC + SSM. Both were cost-effective in 100% of 1000 simulations.

Conclusions

Given the high clinical benefits and low incremental costs, systematic smoking cessation interventions should be a standard component of first-line cancer treatment.
LIM domain only 7: a novel driver of immune evasion through regulatory T cell differentiation and chemotaxis in pancreatic ductal adenocarcinoma
Authors: Dai Shangnan , Peng Yunpeng , Wang Guangfu , Chen Chongfa , Chen Qiuyang , Yin Lingdi , Yan Han , Zhang Kai , Tu Min , Lu Zipeng , Wei Jishu , Li Qiang , Wu Junli , Jiang Kuirong , Zhu Yi , Miao Yi
Published: August 2024

With advancements in genomics and immunology, immunotherapy has emerged as a revolutionary strategy for tumor treatment. However, pancreatic ductal adenocarcinoma (PDAC), an immunologically “cold” tumor, exhibits limited responsiveness to immunotherapy. This study aimed to address the urgent need to uncover PDAC’s immune microenvironment heterogeneity and identify the molecular mechanisms driving immune evasion. Using single-cell RNA sequencing datasets and spatial proteomics, we discovered LIM domain only 7 (LMO7) in PDAC cells as a previously unrecognized driver of immune evasion through Treg cell enrichment. LMO7 was positively correlated with infiltrating regulatory T cells (Tregs) and dysfunctional CD8+ T cells. A series of in vitro and in vivo experiments demonstrated LMO7’s significant role in promoting Treg cell differentiation and chemotaxis while inhibiting CD8+ T cells and natural killer cell cytotoxicity. Mechanistically, LMO7, through its LIM domain, directly bound and promoted the ubiquitination and degradation of Foxp1. Foxp1 negatively regulated transforming growth factor-beta (TGF-β) and C-C motif chemokine ligand 5 (CCL5) expression by binding to sites 2 and I/III, respectively. Elevated TGF-β and CCL5 levels contribute to Treg cell enrichment, inducing immune evasion in PDAC. Combined treatment with TGF-β/CCL5 antibodies, along with LMO7 inhibition, effectively reversed immune evasion in PDAC, activated the immune response, and prolonged mouse survival. Therefore, this study identified LMO7 as a novel facilitator in driving immune evasion by promoting Treg cell enrichment and inhibiting cytotoxic effector functions. Targeting the LMO7-Foxp1-TGF-β/CCL5 axis holds promise as a therapeutic strategy for PDAC.
Generation of a conditional cellular senescence model using proximal tubule cells and fibroblasts from human kidneys
Authors: Shao Xiaohang , Xu Huaming , Kim Hyojin , ljaz Sadaf , Beier Fabian , Jankowski Vera , Lellig Michaela , Vankann Lucia , Werner Jan Niklas , Chen Lu , Ziegler Susanne , Kuppe Christoph , Zenke Martin , Schneider Rebekka K. , Hayat Sikander , Saritas Turgay , Kramann Rafael
Published: August 2024

Emerging evidence highlights cellular senescence’s pivotal role in chronic kidney disease (CKD). Proximal tubule epithelial cells (PTECs) and fibroblasts are major players in CKD and serve as cellular sources of senescence. The generation of a conditionally immortalized human kidney cell model would allow to better understand the specific mechanisms and factors associated with cellular senescence in a controlled setting, devoid of potential confounding factors such as age and comorbidities. In addition, the availability of human kidney cell lines for preclinical research is sparse and most cell lines do not reflect their in vivo counterparts due to their altered behavior as immortalized cancer-like cells. In this study, PTECs and fibroblasts from human kidneys were isolated and transduced with doxycycline-inducible simian virus 40 large T antigen (SV40LT) vector. By comparing their gene expression with single-cell RNA sequencing data from human kidneys, the newly produced human kidney cell lines demonstrated significant resemblances to their in vivo counterparts. As predicted, PTECs showed functional activity and fibroblasts responded to injury with fibrosis. Withdrawal of the immortalizing factor doxycycline led to p21+ cell-cycle arrest and the key hallmarks of senescence. The obtained senescence gene set largely overlapped between both cell lines and with the previously published SenMayo set of senescence-associated genes. Furthermore, crosstalk experiments showed that senescent PTECs can cause a profibrotic response in fibroblasts by paracrine actions. In 76 human kidney sections, the number of p21+ cells correlated with the degree of fibrosis, age and reduced glomerular filtration, validating the role of senescence in CKD. In conclusion, we provide a novel cellular ex vivo model to study kidney senescence which can serve as a platform for large scale compounds testing.