bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of evolutionary computation and guide curves to optimize the operating policies of a reservoir system established to supply drinking water
Authors: Carmona-Paredes Rafael Bernardo , Domínguez-Mora Ramón , Arganis-Juárez Maritza Liliana , Juan-Diego Eduardo , Mendoza-Ramírez Rosalva , Carrizosa-Elizondo Eliseo
Published: November 2022

The objective of the present study was to develop a genetic algorithm capable of establishing optimal operating policies for monthly extractions from the three main reservoirs of the Cutzamala System, which supply drinking water to the Mexico City metropolitan area. In previous studies, annual water extraction defined with an annual Z curve in terms of the total water storage in the reservoirs on November 1 was optimized using genetic algorithms. In this study, a percentage of total annual extraction for each reservoir was also optimized, but monthly water extractions were adjusted too, when the water level fell outside the upper or lower limits of guide curves stablished for each reservoir. The capabilities of the genetic algorithms combined with a detailed simulation of reservoirs operation were used to optimize the levels of the guide curves and also to optimize the adjusted monthly programed extractions as linear functions of the difference between the actual storage level at the beginning of each month and the corresponding level of the guide curves. Therefore, 90 parameters were established: four to define the Z curve, two to establish the percentage assigned to each reservoir, 72 to establish the monthly levels of the guide curves and 12 to define the parameters of the linear functions used to adjust the monthly programed extractions when the actual water level exceeds the limits of the guide curves. For each alternative of the 90 parameters, a detailed simulation is done using the last 20 years of hydrological data on the inflow of water to the three main reservoirs, including the net contributions of five diversion dams, and the objective function sought to maximize water delivery to the treatment plant, while penalizing possible spills and deficits in the system is evaluated. The optimal policies found in this research resulted in smaller spills than those that occurred during the historical operation of the reservoir system. Therefore, the optimal monthly operating decisions required for each reservoir are provided by the genetic algorithm.
Numerical model of seepage flows by reformulating finite element method based on new spherical Hankel shape functions
Authors: Farmani Sajedeh , Ghaeini-Hessaroeyeh Mahnaz , Hamzehei-Javaran Saleh
Published: November 2022

The water penetration in soil is investigated numerically using the finite element method (FEM) in a novel way. In the suggested method, new spherical Hankel shape functions are used and the finite element method is reformulated based on them. These new functions are obtained from the first and second kind of Bessel functions. The properties of Hankel shape functions lead to having more accuracy and robustness for the proposed method with low number of elements. To validate the suggested approach, at first, a boundary value problem is solved and the results are compared with the available analytical solution. Then, in order to prove the efficiency and applicability of the present model in the seepage problems, five examples including saturated and unsaturated flow in porous media are studied and the hydraulic head is calculated. Afterward, the results obtained from the classical and new method are compared together. The comparisons indicate that the suggested method with the low number of elements is more precise than the classic FEM with the same mesh.
Numerical solution of the three-dimensional Burger’s equation by using the DQ-FD combined method in the determination of the 3D velocity of the flow
Authors: Rezaei Iman , Vaghefi Mohammad
Published: November 2022

In this paper, the differential quadrature and the finite difference combined method (DQ-FDM) was applied to solve the three-dimensional Burger’s equation in the determination of the 3D velocity of the flow; so that spatial terms were discretized by the differential quadrature method, and the temporal term was discretized by the finite difference method, and the resulting nonlinear equations were solved using the Newton–Raphson method. All variables were considered as dimensionless in this equation. The solution results were compared with solution results of the two-dimensional equation in the two other numerical methods available in the literature which provided an acceptable accuracy. Also, the results of the mentioned numerical method were compared with those of the fully implicit finite difference method that was solved for larger than or equal viscosities of 0.1. The results showed that by increasing time and viscosity, the longitudinal, depth and transverse velocities were decreased. The occurrence of the upward flow was observed especially in the $$\upsilon$$
υ
 = 0.05 in the close of the bed, end of the length and width that in the presence of very fine particles of the clay and silt shows suspension of these particles in some spaces. The position of the longitudinal, depth and transverse velocities in the plan for the passing plates through the section depth for different viscosities and times showed that by increasing viscosity and time, the position of the maximum velocities became closer to the middle of the section width. Also, stream lines were plotted in all of sections and then analyzed.
Evaluation of the controllability of a remotely piloted high-altitude platform in atmospheric disturbances based on pilot-in-the-loop simulations
Authors: Hasan Yasim J. , Roeser Mathias S. , Voigt Andreas E.
Published: November 2022

In the context of the project HAP, the German Aerospace Center (DLR) is currently developing a solar-powered high-altitude platform that is supposed to be stationed in the stratosphere for 30 days. The development process includes the design of the aircraft, its manufacturing and a flight test campaign. Furthermore, a high-altitude demonstration flight is planned. While the high-altitude flight will be performed using a flight control and management system, during take-off and landing and at the beginning of the low-altitude flight test campaign, the aircraft will be remotely piloted. The aircraft has a wing span of 27 m and operates at extremely low airspeeds, being in the magnitude of around 10 m/s equivalent airspeed, and is therefore profoundly susceptible to atmospheric disturbances. This is particularly critical at low altitudes, where the airspeed is lowest. Hence, both time and location for take-off, landing or low-altitude flight test campaigns need to be selected thoroughly to reduce the risk of a loss of aircraft. In this regard, the knowledge about the operational limits of the aircraft with respect to atmospheric conditions is crucial. The less these limits are known, the more conservative the decision about whether to perform a flight on a certain day or not tends to be. On the contrary, if these limits have been adequately investigated, the amount of days and locations that are assessed as suitable for performing a flight might increase. This paper deals with a pilot-in-the-loop simulation campaign that is conducted to assess the controllability of the high-altitude platform in atmospheric disturbances. Within this campaign, the pilots are requested to perform practical tasks like maintaining track or altitude, flying a teardrop turn or performing a landing while the aircraft is subject to different atmospheric disturbances including constant wind, wind shear, continuous turbulence, and discrete gusts of different magnitudes. This paper describes the desktop simulator used for the campaign, outlines the entity of investigated test points and presents the assessment method used to evaluate the criticality of the respective disturbances. Finally, a set of restrictions on the acceptable wind conditions for the high-altitude platform are found. The underlying limits comprise a constant wind speed of 3.0 m/s in any direction, except during landing, maximum wind shear of 0.5 $$\text { m/s}^{2}$$

m/s
2

and gusts with peak speeds of 1.5 to 2.0 m/s, depending on the direction.
Robotic versus laparoscopic distal pancreatectomy on perioperative outcomes: a systematic review and meta-analysis
Authors: Li Pengyu , Zhang Hanyu , Chen Lixin , Liu Tiantong , Dai Menghua
Published: November 2022

Robotic surgery has become a promising surgical method in minimally invasive pancreatic surgery due to its three-dimensional visualization, tremor filtration, motion scaling, and better ergonomics. Numerous studies have explored the benefits of RDP over LDP in terms of perioperative safety and feasibility, but no consensus has been achieved yet. This article aimed to evaluate the benefits and drawbacks of RDP and LDP for perioperative outcomes. By June 2022, all studies comparing RDP to LDP in the PubMed, the Embase, and the Cochrane Library database were systematically reviewed. According to the heterogeneity, fix or random-effects models were used for the meta-analysis of perioperative outcomes. Odds ratio (OR), weighted mean differences (WMD), and 95% confidence intervals (CI) were calculated. A sensitivity analysis was performed to explore potential sources of high heterogeneity and a trim and fill analysis was used to evaluate the impact of publication bias on the pooled results. Thirty-four studies met the inclusion criteria. RDP provides greater benefit than LDP for higher spleen preservation (OR 3.52 95% CI 2.62–4.73, p < 0.0001) and Kimura method (OR 1.93, 95% CI 1.42–2.62, p < 0.0001) in benign and low-grade malignant tumors. RDP is associated with lower conversion to laparotomy (OR 0.41, 95% CI 0.33–0.52, p < 0.00001), and shorter postoperative hospital stay (WMD − 0.57, 95% CI − 0.92 to − 0.21, p = 0.002), but it is more costly. In terms of postoperative complications, there was no difference between RDP and LDP except for 30-day mortality (RDP versus LDP, 0.1% versus 1.0%, p = 0.03). With the exception of its high cost, RDP appears to outperform LDP on perioperative outcomes and is technologically feasible and safe. High-quality prospective randomized controlled trials are advised for further confirmation as the quality of the evidence now is not high.
Considerations on the Systematics of Neotropical Pierina, with the Description of Two New Species of Phulia Herrich-Schäffer from the Peruvian Andes (Lepidoptera: Pieridae, Pierinae, Pierini)
Authors: Pyrcz Tomasz W. , Willmott Keith R. , Lamas Gerardo , Boyer Pierre , Florczyk Klaudia , Fåhraeus Christer , Mahecha Oscar , Cerdeña José , Mrozek Artur , Farfán Jackie , Zubek Anna
Published: November 2022

A comparative analysis of high-Andean Pierina was carried out, including a total of 25 species. Based on morphological evidence, with an emphasis on venation and genitalia and molecular data, using three genetic markers, we confirm the recent subjective synonymy of the generic names Tatochila Butler, 1870, Piercolias, Staudinger, 1894, Hypsochila Ureta, 1955, Infraphulia Field, 1958, Pierphulia Field, 1958, and Theochila Field, 1958 with Phulia Herrich-Schäffer, 1867. Two new species are described, namely Phulia stoddardi Pyrcz & Cerdeña n. sp., from the Andes of Central Peru, which occurs at an unusually high altitude of close to 5000 m a.s.l. in dry puna habitat, and Phulia phantasma Lamas, Willmott & Boyer n. sp., from dry montane forests in northern Peru and southern Ecuador. An overview of high-elevation butterflies is presented, with some discussion on adaptations to this environment.
Biology of house dust mites and storage mites
Authors: Bergmann Karl-Christian
Published: November 2022

House dust mites and storage mites have a high allergenic potential and lead to sensitization through the formation of specific IgE antibodies. Due to their preferred residence in houses, they belong to the group of house mites, which are referred to as “domestic mites” in English. Their anatomy and biology account for their amazing adaptability to changing environmental situations (including temperature, humidity, food) and make it understandable that measures to reduce their abundance are usually difficult to implement in practice.
Wear-Induced Attenuation on Transmission Lines and Their Causes
Authors: Lenz Philipp , Baron Philipp , Wittmann Armin , Fischer Georg
Published: November 2022

In this paper, the radio frequency (RF) behavior of mechanically stressed coaxial and for the first time also twisted-pair transmission lines is investigated over their service life. The main goal is to enable predictive maintenance for cables in moving applications and avoid preventive replacement. This also reduces the use of high-cost resources. For this purpose, stranded and solid-core variants of coaxial and twisted-pair type cables are mechanically loaded on the two-pulley apparatus according to EN 50396. Their RF transmission (S21) behavior is measured using a vector network analyzer and presented over bending cycles. For the first time, the phase response of mechanically loaded transmission lines is evaluated with respect to their service life. Two significant causes for the increasing attenuation and altered phase response are identified: breakage in foil screen and increasing surface roughness on the copper conductors. The identified causes are supported with literature evidence. Through measurements and theoretical calculations, it is proven that the phase is much more suitable for an assessment of the remaining service life than the amplitude. The findings can be used to implement a cable monitoring system in industrial environments which monitors the lines in-situ and reminds the user to replace them, whenever a certain wear-level is reached.
Deep learning prediction of amplitude death
Authors: Ji Pengcheng , Yu Tingyi , Zhang Yaxuan , Gong Wei , Yu Qingyun , Li Li
Published: November 2022

Affected by parameter drift and coupling organization, nonlinear dynamical systems exhibit suppressed oscillations. This phenomenon is called amplitude death. In various complex systems, amplitude death is a typical critical phenomenon, which may lead to the functional collapse of the system. Therefore, an important issue is how to effectively predict critical phenomena based on the data in the system oscillation state. This paper proposes an enhanced Informer model to predict amplitude death. The model employs an attention mechanism to capture the long-range associations of the system time series and tracks the effect of parameter drift on the system dynamics through an accompanying parameter input channel. The experimental results based on the coupled Rössler and Lorentz systems show that the enhanced informer has higher prediction accuracy and longer effective prediction distance than the original algorithm and can predict the amplitude death of a system.
Sediment erodibility in the Changjiang (Yangtze) subaqueous delta: spatial–temporal distribution and sedimentary significance
Authors: Xu Chaoran , Wei Dongyun , Chen Yining , Yang Yang , Zhang Fan , Wang Ya Ping , Jia Jianjun
Published: November 2022

Delta evolution in the context of no sediment discharge has become a global concern, and an accretion-to-erosion conversion is occurring in the Yangtze estuary. This conversion could threaten Changjiang subaqueous delta development. Sediment erodibility is an important indicator of subaqueous delta vulnerability. However, the present and future erodibility of the Changjiang subaqueous delta remains unclear. In this study, 37 short cores were collected from the Changjiang subaqueous delta, and the critical shear stress of the sediment was measured using a cohesive strength meter (CSM) and compared with estimates based on an empirical Shields diagram. The sediment erodibility was analyzed by comparing the sediment critical shear stress with the bed shear stress simulated using a numerical model (i.e., FVCOM), and sediment activity was introduced to discuss the geomorphological change in the subaqueous delta. The CSM-derived critical shear stress is significantly higher than that derived from the empirical Shields formula, but it better shows the erodibility of the sediment. The annual surface sediment activity ranges from 5% to 30% based on the CSM, indicating low surface erodibility. Moreover, the critical shear stress in this region increases as water depth increases, but the bed shear stress shows the opposite trend. Therefore, the erodibility of the Changjiang subaqueous delta is lower than that of the shallow area, indicating no accretion-erosion conversion or continued vertical erosion under sediment starvation in the coming decades. These findings can provide suggestions for erosion assessment and management in large river deltas under decreasing sediment discharge.
Characteristics of COVID-19 (Delta Variant)/HIV Co-infection: A Cross-sectional Study in Henan Province, China
Authors: Yang Rui , Cheng Jiuling , Song Xiangjin , Pan Yuanwei , Wang Huaqi , Li Jing , He Xudong , Gou Jianjun , Zhang Guojun
Published: November 2022

Background

Since the end of July 2021, SARS-CoV-2 (Delta variant) invaded Henan Province, China, causing a rapid COVID-19 spread in the province. Among them, the clinical features of COVID-19 (Delta Variant)/HIV co-infection have attracted our attention.

Methods

We included 12 COVID-19 patients living with HIV (human immunodeficiency virus) from July 30, 2021 to September 17, 2021 in Henan Province, China. Demographic, clinical, laboratory, and computed tomography (CT) imaging data were dynamically collected from first nucleic acid positive to hospital discharge. Laboratory findings included SARS-CoV-2 viral load, HIV viral load, IgM, IgG, cytokines, lymphocyte subpopulation, ferritin, etc. Statistical analyses were performed using IBM SPSS version 26·0 and GraphPad Prism version 9·0.

Results

It was founded that the low Ct value persisted for about 21 days, and the viral shedding time (turn negative time) of the patients was 32·36 ± 2·643 days. Furthermore, chest CT imaging revealed that lesions were obviously and rapidly absorbed. It was surprising that IgM levels were statistically higher in patients taking azvudine or convalescent plasma than in patients not taking these drugs (P < 0·001, P = 0·0002, respectively). IgG levels were significantly higher in patients treated with the combined medication of BRII/196 and BRII/198 than in those not treated with these drugs (P = 0·0029). IgM was significantly higher in those with low HIV viral load than those with high HIV viral load (P < 0·001). In addition, as treatment progressed and patients' condition improved, IL-17a showed a decreasing trend.

Conclusions

Based on this study, we found that HIV infection might not exacerbate COVID-19 severity.
Measuring the risk of corruption in Latin American political parties. De jure analysis of institutions
Authors: Rodríguez-García Giovanna
Published: November 2022

Research that examines the impact of economic, social, and political factors on political corruption uses expert’ and citizen’ perceptions for measuring corruption and testing arguments. Scholars argue that the perception of corruption is a good proxy for actual corruption because data on actual corruption are limited and not entirely trustworthy. However, perception indexes do not allow for testing separate mechanisms driving citizen’ perceptions of corruption from actual levels of corruption in different government branches. To address this issue, I introduce a new index based on Latin American countries to measure the risk of corruption in political parties. Using a de jure analysis of laws and regulations, the Risk of Corruption (ROC) index evaluates the likelihood of political parties engaging in corrupt activities. Instead of measuring corrupt activities or perception directly, the ROC measures the risks of involving in corruption. The index has important implications for academics and practitioners in anti-corruption issues. First, it allows us to test arguments about the role of political parties and legislatures in reducing political corruption. Second, it helps to understand how political parties could improve their internal organization to decrease the risk of corrupt activities. Finally, it is a valuable instrument for cross-national studies in diverse fields that study political parties.
Anthropogenic Heathlands in Prehistoric Atlantic Europe: Review and Future Prospects
Authors: Ombashi Havananda , Løvschal Mette
Published: November 2022

Heathlands are unique cultural landscapes that once existed across vast stretches of northern Europe. Their deep-time persistence has formed an intrinsic part of economic and cultural practices. Such a complex interaction requires interdisciplinary approaches, including archaeology, across multiple regions to fully grasp all its aspects. The authors of this article review how research has been conducted in prehistoric heathlands across six nations in north-western Europe and outline the heaths’ general characteristics. They discuss the major issues in that research, namely recurring narratives derived from history, an overall absence of consideration of the cultural aspects of heathlands, and a paucity of cross-regional initiatives. They suggest a series of theoretical and methodological approaches to improve this situation across expanded geographical and temporal scales.
Distinction and Survival: Zoroastrians, Religious Nationalism, and Cultural Ownership in Shiʿi Iran
Authors: Fozi Navid
Published: November 2022

This article argues that the notion of Iranian culture employed in the public discourse of Zoroastrians allows them to tackle the dilemma of Shiʿi-dominated Iranianness without provoking Shiʿi authorities. The piece offers an analysis of ethnographic data, including detailed speech acts documented in Zoroastrians’ ritual spaces and cultural exhibitions. It explores the Zoroastrian configuration of an Iranian culture that summons and encodes pre-Islamic tropes and modern nationalist sentiments by constantly maneuvering around national, religious, and ethnic categories. This configuration's underpinning assumptions, narratives, and texts have powerful platforms in Iranian nationalist imagination. I propose that this arrangement attempts to carve out a space for Zoroastrians’ distinct identity by connecting the history of the Muslim Arab invasion of Persia to the Shiʿi hegemonic norms of Iranian culture today. It further invokes Zoroaster's indigeneity and teachings as the foundation of authentic Iranianness to establish Zoroastrians’ survival as a cultural system.
Curves on the torus intersecting at most k times
Authors: AOUGAB TARIK , GASTER JONAH
Published: November 2022

We show that any set of distinct homotopy classes of simple closed curves on the torus that pairwise intersect at most k times has size
$k+O(\sqrt k \log k)$
. Prior to this work, a lemma of Agol, together with the state of the art bounds for the size of prime gaps, implied the error term
$O(k^{21/40})$
, and in fact the assumption of the Riemann hypothesis improved this error term to the one we obtain
$O(\sqrt k\log k)$
. By contrast, our methods are elementary, combinatorial, and geometric.
PERMUTATION-BASED PRESENTATIONS FOR BRIN’S HIGHER-DIMENSIONAL THOMPSON GROUPS
Authors: QUICK MARTYN
Published: November 2022

The higher-dimensional Thompson groups
$nV$
, for
$n \geqslant 2$
, were introduced by Brin [‘Presentations of higher dimensional Thompson groups’, J. Algebra284 (2005), 520–558]. We provide new presentations for each of these infinite simple groups. The first is an infinite presentation, analogous to the Coxeter presentation for the finite symmetric group, with generating set equal to the set of transpositions in
$nV$
and reflecting the self-similar structure of n-dimensional Cantor space. We then exploit this infinite presentation to produce further finite presentations that are considerably smaller than those previously known.
Psychosocial palliative care: Patients’ preferred intervention medium, target domains, and well-being priorities
Authors: Pakenham Kenneth , Martin Christopher Lloyd
Published: November 2022

Objectives

Although psychological distress in palliative patients has at least an equal or greater impact on the quality of life compared to physical or spiritual distress, there is limited research on contextual factors associated with psychosocial intervention accessibility and relevance. This is the first published study to explore patients’ views on psychosocial intervention delivery medium preferences, key biopsychosocial target domains, and well-being priorities during the palliative and end-of-life (EOL) phases.

Methods

Eighty-one palliative patients from a Specialist Palliative Care Service completed a questionnaire, which collected quantitative and qualitative data on preferred mediums for receiving psychosocial interventions, priority biopsychosocial target domains, and well-being priorities during the palliative and EOL phases.

Results

Results showed that an individual in-person was the most preferred medium for receiving psychosocial interventions. Improving quality of life, distressing emotions, and adjusting to the palliative care context were the 3 most frequently endorsed biopsychosocial target domains. Valued living and comfortable living were the key priority well-being themes for the palliative phase, whereas being surrounded by loved ones and comfortable and dignified dying were the priority well-being themes for the EOL phase.

Significance of results

Findings highlight psychosocial interventions as an essential part of a holistic approach to patient-centered care throughout both the palliative and the EOL phases. Results can inform the refinement of existing and the development of new psychosocial interventions, particularly those that target emotional distress, adjustment, and quality of life. Furthermore, in-person treatment delivery remains essential in an evolving digital world.
Hydrodynamic Modeling of Inundation Patterns of a Large African Floodplain Indicates Sensitivity to Waterway Restoration
Authors: Willis T. D. M. , Smith M. W. , Cross D. E. , Hardy A. J. , Ettrich G. E. , Malawo H. , Chalo C. , Sinkombo M. , Thomas C. J.
Published: November 2022

Large‐scale floodplains are important features of the African continent. Regular inundation provides the means to support large populations but can also present problems such as access to health facilities and water body formation that sustain malaria vectors. Modeling of these floodplains is therefore important, but complex. In this research, we develop, calibrate, and validate a hydrodynamic model of the Barotse Floodplain, of the Upper Zambezi, Zambia. The floodplain has seen recent infrastructure developments including the restoration of the canal network and construction of a cross floodplain causeway. In order to create a robust model, a multiobjective calibration uses a time slice approach based on available Landsat satellite image overpasses. An emulator‐based sensitivity analysis indicates the significance of hydrological processes in the model. Model evaluation is undertaken for two events in the gauge record (2009 and 2018), of similar magnitude that occur before and after modifications to the floodplain. Results indicate a complex impact of infrastructure development on the hydrodynamics of the floodplain, with a higher peak flow, but with a redistribution of water throughout the floodplain. Deeper flooding is observed in some areas while others experience lower water levels. The sensitivity results also reflect a change in processes, where floodplain flows dominate the 2009 event, whilst channel process dominate the 2018 event. Overall, we show that relatively modest modifications to the floodplain have impacted flood water levels, which in turn will influence access route availability and alter malaria transmission rates.
The Bottom of the Arctic Is Blooming
Authors: Szakal Fanni
Published: November 2022

Researchers found phytoplankton hidden on the Arctic seafloor, hinting at a cascade of effects on the local ecology and carbon cycle.
Development and Emplacement of Ana Slide, Eivissa Channel, Western Mediterranean Sea
Authors: Sager Thore F. , Urlaub Morelia , Kaminski Pauline , Papenberg Cord , Lastras Galderic , Canals Miquel , Berndt Christian
Published: November 2022

Submarine landslides can destroy seafloor infrastructures and generate devastating tsunamis. In spite of decades of research into the functioning of submarine landslides there are still numerous open questions, in particular how different phases of sliding influence each other. Here, we re‐analyze Ana Slide—a relatively small (<1 km3) landslide offshore the Balearic Islands, which is unique in the published literature because it is completely imaged by high‐resolution 3D reflection seismic data. Ana Slide comprises three domains: (a) a source area that is almost completely evacuated with evidence of headscarp retrogression, (b) an adjacent downslope translational domain representing a by‐pass zone for the material that was mobilized in the source area, and (c) the deposit formed by the mobilized material, which accumulated downslope in a sink area and deformed slope sediment. Isochron maps show deep chaotic seismic units underneath the thickest deposits. We infer that the rapid deposition of the landslide material deformed the underlying sediments. A thin stratified sediment unit between three lobes suggests that Ana Slide evolved in two failure stages separated by several tens of thousands of years. This illustrates the problem of over‐estimating the volume of mobilized material and under‐estimating the complexity even of relatively simple slope failures without high‐quality 3D reflection seismic data.
The Fate of Sedimentary Reactive Iron at the Land‐Ocean Interface: A Case Study From the Amazon Shelf
Authors: Vosteen Paul , Spiegel Timo , Gledhill Martha , Frank Martin , Zabel Matthias , Scholz Florian
Published: November 2022

Reactive iron (Fe) oxides in marine sediments may represent a source of bioavailable Fe to the ocean via reductive dissolution and sedimentary Fe release or can promote organic carbon preservation and long‐term burial. Furthermore, enrichments of reactive Fe (sum of Fe oxides, carbonates and sulfides normalized to total Fe) in ancient sediments are utilized as a paleo‐proxy for anoxic conditions. Considering the general importance of reactive Fe oxides in marine biogeochemistry, it is important to quantify their terrestrial sources and fate at the land‐ocean interface. We applied sequential Fe extractions to sediments from the Amazon shelf to investigate the transformation of river‐derived Fe oxides during early diagenesis. We found that ∼22% of the Amazon River‐derived Fe oxides are converted to Fe‐containing clay minerals in Amazon shelf sediments. The incorporation of reactive Fe into authigenic clay minerals (commonly referred to as reverse weathering) is substantiated by the relationship between Fe oxide loss and potassium (K) uptake from sedimentary pore waters, which is in agreement with the previously reported Fe/K stoichiometry of authigenic clay minerals. Mass balance calculations suggest that widely applied sequential extractions do not separate Fe‐rich authigenic clay minerals from reactive Fe oxides and carbonates. We conclude that the balance between terrestrial supply of reactive Fe and reverse weathering in continental margin sediments has to be taken into account in the interpretation of sedimentary Fe speciation data.
Why Is Seasonal Density Stratification in Shelf Seas Expected to Increase Under Future Climate Change?
Authors: Holt Jason , Harle James , Wakelin Sarah , Jardine Jenny , Hopkins Joanne
Published: November 2022

Coastal and shelf seas provide a diverse range of ecosystem services, which are often mediated by seasonal density stratification through its control on biogeochemical cycles. These seas are highly vulnerable to climate change and downscaling studies consistently project an increase in seasonal stratification over the next century, but without a clear explanation. Here we revisit a well‐established theory of coastal ocean mixing and demonstrate with a new ensemble of downscaled simulations for the Northwest European continental shelf seas to 2100 that the increase of expansivity with temperature is sufficient to consistently increase the seasonal stratification. Where there is a closed balance between buoyancy input and mixing, small changes in expansivity are amplified to a large relative change in stratification. This simple link between global heating and stratification substantially reduces uncertainty in projections of this key parameter in seas around the world.
1,100‐Year Reconstruction of Baseflow for the Santee River, South Carolina, USA Reveals Connection to the North Atlantic Subtropical High
Authors: Maxwell Justin T. , Harley Grant L. , Tucker Clay S. , Galuska Toudora , Ficklin Darren L. , Bregy Joshua C. , Heeter Karen J. , Au Tsun Fung , Lockwood Benjamin R. , King Daniel J. , Maxwell R. Stockton , Smith Laura G. , Elliott Emily A. , Therrell Matthew D.
Published: November 2022

Since 2013, extreme floods within the Santee River basin (North/South Carolina, USA) caused $1.5B in damage. The instrumental period, however, is too short to determine if recent extreme events are anomalous within a long‐term context. Here, we present reconstructions of storm‐, base‐, and total streamflow for the Santee River using a multi‐species tree‐ring network calibrated to flow data during the period 1923–2018. Tree‐ring data explained higher variance (r = 0.59; p < 0.01; 900–2018) of instrumental baseflow than total streamflow (r = 0.41; p < 0.01; 1500–2018) or stormflow (r = 0.26; p < 0.05; 1690–2018). Our reconstruction reveals a long‐term increase in baseflow over the past millennium. The North Atlantic subtropical high regulates baseflow in the Santee River (r = 0.45; p < 0.01). Recent high levels of baseflow may be connected to the position of the subtropical high, increasing the likelihood of flooding.
Marine Ooid Sizes Record Phanerozoic Seawater Carbonate Chemistry
Authors: Trower Elizabeth J. , Smith Benjamin P. , Koeshidayatullah Ardiansyah I. , Payne Jonathan L.
Published: November 2022

Seawater carbonate chemistry links Earth's climate and carbon cycle through the production and preservation of carbonate sediments. Models and carbonate facies abundance records have generated hypotheses about trajectories of seawater carbonate chemistry, including responses to key events in the evolutionary history of carbonate biomineralizers. However, tests of these hypotheses have remained elusive. We applied a novel proxy for the carbonate mineral saturation state (Ω) of seawater based on the diameters of ooids—concentrically‐coated carbonate sand grains—to estimate Ω, dissolved inorganic carbon, alkalinity, and pH of seawater spanning Phanerozoic time. Reconstructed Ω values decreased sharply around ∼120 Ma, which we interpret as the fingerprint of the Mid‐Mesozoic Revolution of planktic calcifiers. Shifts in Ω across Ordovician time also suggest a possible causal relationship with the Great Ordovician Biodiversification Event. Our results demonstrate that ooid sizes are a useful tool for reconstructing Earth's ancient carbon cycle.
Upward Bipolar Lightning Flashes Originated From the Connection of Recoil Leaders With Intracloud Lightning
Authors: Cruz Ivan T. , Saba Marcelo M. F. , Schumann Carina , Warner Tom A.
Published: November 2022

The present work shows high‐speed videos of two upward flashes that started with positive upward leaders and, instead of being followed by negative subsequent return strokes, they were followed by positive subsequent return strokes. In both cases, after the positive leaders developed, recoil leaders (RL) appeared in their decayed branches as would be usual in negative upward lightning flashes. However, in these flashes the negative end of a recoil leader connected to a positive leader of an intracloud (IC) flash nearby. The connection initiated a downward positive leader that re‐ionized the decayed channel of the upward flash all the way to the tower giving origin to a positive subsequent return stroke. This work shows that RL do play an important role in the occurrence of bipolar upward flashes and their interaction with IC flashes can provide explanations for all types of bipolar upward flashes initiated by upward positive leaders.
Receiver Function Mapping of the Mantle Transition Zone Beneath the Tian Shan Orogenic Belt
Authors: Liu Dongyang , Zhao Liang , Yuan Huaiyu , Sun Weijia , Xiao Wenjiao
Published: November 2022

This study provides new constraints on the mantle transition zone (MTZ) structure under the Tian Shan orogenic belt in the context of the double‐sided subduction of the Junggar lithosphere and the Tarim lithosphere. The 410‐ and 660‐km discontinuities bordering the MTZ under the Tian Shan and its adjacent areas are mapped by stacking 68,361 receiver functions from 4,122 events recorded by 100 broadband seismic stations. Regional and large‐scale 3‐D velocity models are used to explain the effect of the laterally heterogeneous velocity anomalies. We identify a thickened MTZ of about 9.3 km under the eastern Tian Shan and the Darbut belt. This thickening indicates a lower temperature, which is correlated with the broken‐off subducted lithosphere or the delamination of the eastern Tian Shan lithosphere. We document the thinning of the MTZ caused by the depressed 410‐km discontinuity and the uplifted 660‐km discontinuity across the Tian Shan orogenic belt, Junggar Basin and Tarim Basin. This thinning corresponds to a + 100 K thermal anomaly in the MTZ, and we suggest that it may have been produced by thermal upwelling originating from the lower mantle. The slightly thinned MTZ beneath the Altai Mountains was caused by the uplift of these two discontinuities, which is related to the high‐velocity anomalies in the upper mantle and MTZ. In contrast, the thinned MTZ below the easternmost segment of the Tian Shan orogenic belt, formed by the depression of 6.5 km for the 410‐km discontinuity may indicate the presence of small‐scale mantle upwelling.
Predicting Hydrological Drought With Bayesian Model Averaging Ensemble Vine Copula (BMAViC) Model
Authors: Wu Haijiang , Su Xiaoling , Singh Vijay P. , Zhang Te
Published: November 2022

Streamflow deficit (hydrological drought) poses a large risk to water resources management, agricultural production, water supply, hydropower generation, and ecosystem services. Reliable and robust hydrological drought predictions are critical for water and food security and ecosystem health under anthropogenic warming. However, the prevalent statistical prediction methods, for example, the meta‐Gaussian (MG) model, usually do not lead to accurate drought predictions. We therefore developed a new drought prediction model utilizing the Bayesian Model Averaging coupled with Vine Copula, called Bayesian Model Averaging Ensemble Vine Copula (BMAViC) model, in which previous meteorological drought, antecedent evaporative drought, and preceding hydrological drought were selected as three predictors. The BMAViC model was applied to the Upper Yellow River basin and showed robust skills during calibration and validation periods for 1‐ to 3‐month lead hydrological drought predictions. In comparison with the MG model (reference model), the skills of the proposed model were relatively stable and superior under diverse lead times. Good performances under the 1‐ to 3‐month lead times strongly implied that the BMAViC model yielded robust and accurate hydrological drought predictions. The study results enhance our confidence in seasonal drought prediction and help us understand drought dynamics in future months.
Protein phosphatases regulate the liver microenvironment in the development of hepatocellular carcinoma
Authors: Yoon Joon-Sup , Lee Chang-Woo
Published: November 2022

The liver is a complicated heterogeneous organ composed of different cells. Parenchymal cells called hepatocytes and various nonparenchymal cells, including immune cells and stromal cells, are distributed in liver lobules with hepatic architecture. They interact with each other to compose the liver microenvironment and determine its characteristics. Although the liver microenvironment maintains liver homeostasis and function under healthy conditions, it also shows proinflammatory and profibrogenic characteristics that can induce the progression of hepatitis and hepatic fibrosis, eventually changing to a protumoral microenvironment that contributes to the development of hepatocellular carcinoma (HCC). According to recent studies, phosphatases are involved in liver diseases and HCC development by regulating protein phosphorylation in intracellular signaling pathways and changing the activities and characteristics of liver cells. Therefore, this review aims to highlight the importance of protein phosphatases in HCC development and in the regulation of the cellular components in the liver microenvironment and to show their significance as therapeutic targets.
Single-cell analysis of multiple myelomas refines the molecular features of bortezomib treatment responsiveness
Authors: Jung Seung-Hyun , Park Sung-Soo , Lim Ji-Young , Sohn Seon Yong , Kim Na Yung , Kim Dokyeong , Lee Sug Hyung , Chung Yeun-Jun , Min Chang-Ki
Published: November 2022

Both the tumor and tumor microenvironment (TME) are crucial for pathogenesis and chemotherapy resistance in multiple myeloma (MM). Bortezomib, commonly used for MM treatment, works on both MM and TME cells, but innate and acquired resistance easily develop. By single-cell RNA sequencing (scRNA-seq), we investigated bone marrow aspirates of 18 treatment-naïve MM patients who later received bortezomib-based treatments. Twelve plasma and TME cell types and their subsets were identified. Suboptimal responders (SORs) to bortezomib exhibited higher copy number alteration burdens than optimal responders (ORs). Forty-four differentially expressed genes for SORs based on scRNA-seq data were further analyzed in an independent cohort of 90 treatment-naïve MMs, where 24 genes were validated. A combined model of three clinical variables (older age, low absolute lymphocyte count, and no autologous stem cell transplantation) and 24 genes was associated with bortezomib responsiveness and poor prognosis. In T cells, cytotoxic memory, proliferating, and dysfunctional subsets were significantly enriched in SORs. Moreover, we identified three monocyte subsets associated with bortezomib responsiveness and an MM-specific NK cell trajectory that ended with an MM-specific subset. scRNA-seq predicted the interaction of the GAS6-MERTK, ALCAM-CD6, and BAG6-NCR gene networks. Of note, tumor cells from ORs and SORs were the most prominent sources of ALCAM on effector T cells and BAG6 on NK cells, respectively. Our results indicate that the complicated compositional and molecular changes of both tumor and immune cells in the bone marrow (BM) milieu are important in the development and acquisition of resistance to bortezomib-based treatment of MM.
Noncoding RNA PVT1 in osteosarcoma: The roles of lncRNA PVT1 and circPVT1
Authors: Wu Tingrui , Ji Ziyu , Lin Hao , Wei Bo , Xie Guohao , Ji Guangju , Fu Shijie , Huang Wenhua , Liu Huan
Published: November 2022

Osteosarcoma (OS) is the most common primary malignant bone tumor in children and teenagers and is characterized by high malignant potential, rapid disease progression and high disability and mortality rates. Recently, noncoding RNAs (ncRNAs) have attracted the attention of many scholars due to their major regulatory roles in gene expression. Among them, lncRNA PVT1 and circPVT1 encoded by the PVT1 gene have been the focus of many studies; they are upregulated in OS, and abundant evidence indicates that lncRNA PVT1 and circPVT1 play key roles in the occurrence and development of OS. This review summarizes the mechanisms of action of lncRNA PVT1 and circPVT1 in regulating apoptosis, proliferation, glycolysis, invasion, migration and epithelial–mesenchymal transition (EMT) in OS and discusses their clinical applications in diagnosis, prognosis determination and drug resistance treatment, with the aim of helping researchers better understand the regulatory roles of lncRNA PVT1 and circPVT1 in OS progression and providing a theoretical basis for the development of early screening and accurate targeted treatment strategies and prognostic biomarkers for OS based on lncRNA PVT1 and circPVT1.
BH3 mimetics in combination with nilotinib or ponatinib represent a promising therapeutic strategy in blast phase chronic myeloid leukemia
Authors: Parry Narissa , Busch Caroline , Aßmann Victoria , Cassels Jennifer , Hair Alan , Helgason G. Vignir , Wheadon Helen , Copland Mhairi
Published: November 2022

Dysregulation of the BCL-2 family is implicated in protecting chronic myeloid leukemia (CML) cells from intracellular damage and BCR::ABL1-inhibition with tyrosine kinase inhibitors (TKIs) and may be a viable therapeutic target in blast phase (BP-)CML, for which treatment options are limited. BH3 mimetics, a class of small molecule inhibitors with high-specificity against the prosurvival members of the BCL-2 family, have displayed clinical promise in the treatment of chronic lymphocytic and acute myeloid leukemia as single agents and in combination with standard-of-care therapies. Here we present the first comparison of inhibition of BCL-2 prosurvival proteins BCL-2, BCL-xL and MCL-1 in combination with a second or third generation TKI, crucially with comparisons drawn between myeloid and lymphoid BP-CML samples. Co-treatment of four BP-CML cell lines with the TKIs nilotinib or ponatinib and either BCL-2 (venetoclax), MCL-1 (S63845) or BCL-xL (A-1331852) inhibitors resulted in a synergistic reduction in cell viability and increase in phosphatidylserine (PS) presentation. Nilotinib with BH3 mimetic combinations in myeloid BP-CML patient samples triggered increased induction of apoptosis over nilotinib alone, and a reduction in colony-forming capacity and CD34+ fraction, while this was not the case for lymphoid BP-CML samples tested. While some heterogeneity in apoptotic response was observed between cell lines and BP-CML patient samples, the combination of BCL-xL and BCR::ABL1 inhibition was consistently effective in inducing substantial apoptosis. Further, while BH3 mimetics showed little efficacy as single agents, dual-inhibition of BCL-2 prosurvival proteins dramatically induced apoptosis in all cell lines tested and in myeloid BP-CML patient samples compared to healthy donor samples. Gene expression and protein level analysis suggests a protective upregulation of alternative BCL-2 prosurvival proteins in response to BH3 mimetic single-treatment in BP-CML. Our results suggest that BH3 mimetics represent an interesting avenue for further exploration in myeloid BP-CML, for which alternative treatment options are desperately sought.
Single-cell sequencing unveils key contributions of immune cell populations in cancer-associated adipose wasting
Authors: Han Jun , Wang Yuchen , Qiu Yan , Sun Diya , Liu Yan , Li Zhigang , Zhou Ben , Zhang Haibing , Xiao Yichuan , Wu Guohao , Ding Qiurong
Published: November 2022

Adipose tissue loss seen with cancer-associated cachexia (CAC) may functionally drive cachexia development. Using single-cell transcriptomics, we unveil a large-scale comprehensive cellular census of the stromal vascular fraction of white adipose tissues from patients with or without CAC. We report depot- and disease-specific clusters and developmental trajectories of adipose progenitors and immune cells. In adipose tissues with CAC, clear pro-inflammatory transitions were discovered in adipose progenitors, macrophages and CD8+ T cells, with dramatically remodeled cell interactome among these cells, implicating a synergistic effect in promoting tissue inflammation. Remarkably, activated CD8+ T cells contributed specifically to increased IFNG expression in adipose tissues from cachexia patients, and displayed a significant pro-catabolic effect on adipocytes in vitro; whereas macrophage depletion resulted in significantly rescued adipose catabolism and alleviated cachexia in a CAC animal model. Taken together, these results unveil causative mechanisms underlying the chronical inflammation and adipose wasting in CAC.