bluuebunny/crossref_metadata_2025 huggingface dataset:
Impeller optimization using a machine learning-based algorithm with dynamic sampling method and flow analysis for an axial flow pump
Authors: Song Xueyi , Li Ying , Huang Renfang , Luo Xianwu
Published: March 2024

Design optimization for widely used axial flow pumps presents a formidable challenge due to the significant impact of numerous parameters associated with impeller geometry on hydraulic performance. The expansive design space raises concerns about the cost and time implications of the optimization process. This paper introduces a machine learning-based algorithm with a dynamic sampling approach to enhance the hydraulic performance of axial flow pumps. The focus is on an axial flow pump designed for China’s South-to-North Water Diversion Project. Optimization involves selecting 15 design variables governing impeller geometry, considering meridional shape and mean blade profiles. The optimization process predicts hydraulic performance using CFD methods, with a primary objective of maximizing efficiency at the axial flow pump’s design point while maintaining pump head around the design value. The results indicate that the proposed machine learning-based algorithm exhibits commendable convergence, delivering a notable improvement in performance. For instance, the optimized axial flow pump displays 2% efficiency increase compared to the initial design. Further analysis employing concepts like entropy generation rate and boundary vorticity flux reveals that the optimized pump has more uniform flow near the pressure side of the impeller blade. Additionally, design optimization effectively suppresses flow separation at the blade trailing edge near the impeller hub. This study offers valuable insights and a practical tool for the design optimization of axial flow pumps.
Monitoring and Early Warning for Hydroelectric Generating Sets based on Hotelling’s T2 and LSTM Model
Authors: Sun Yuxin , Xu Zhuofei , Sun Longgang , Wang Tong , Li Dian
Published: March 2024

A method of monitoring and early warning for hydroelectric generating sets based on Hotelling’s T-squared statistics(T2) and Long Short-Term Memory(LSTM) network is proposed. Multi-channel vibration and swing signals can be fused and predicted based on the given model. The monitoring and alerting function can also be implemented according to a threshold value of T2. First, the vibration and swing signals of multi-channels hydroelectric generating sets are obtained and fused based on Principal Component Analysis(PCA) to reduce the amount of data. Second, Hotelling’s T2 statistics under normal running state is calculated and taken as a warning threshold. Third, a LSTM model is established to predict future values of T2, and early warning for a hydroelectric generating set can be realized by use of the obtained warning threshold. The vibration and swing signals from 16 channels in a set are used to validate the effectiveness of the method. Finally, there is a more than 90% reduction in the amount of data and the efficiency is significantly improved. LSTM has a high accuracy in T2 prediction and realize the early warning for abnormal status.
Study on the permeability behaviour of hydrogen doped natural gas in polyethylene pipeline
Authors: Li Xiang , Shao Puzhen , Wang Jun , Huang Liuyi , Dong Zhi , Zhong Fengping
Published: March 2024

The use of non-metallic PE pipes to transport hydrogen energy can avoid the problem of hydrogen embrittlement in metal pipes, but due to material characteristics, PE pipes exhibit gas leakage behavior. Therefore, this article conducted a study on the permeability of polyethylene (PE100) as a gas pipeline material for hydrogen-doped gas, mainly analyzing the effects of hydrogen content and gas pressure on the permeability of PE100 gas. We ensure that the raw materials are uniform and free from pore defects through microstructure observation and industrial CT characterization. The experimental results show that with the increase of hydrogen content in the hydrogen-doped gas, the gas permeability coefficient of the sample significantly increases. When the hydrogen content is 60%, the gas permeability coefficient increases by 83% compared to when no hydrogen is added. Further increase in hydrogen content results in no significant change in the gas permeability coefficient; As the gas pressure increases, the gas permeability coefficient of the s ample gradually decreases. This study will provide data support for the safe transportation of hydrogen energy and promote the development of the hydrogen energy industry.
Optimization of the active element and reinforcement proportion for improving joint strength of brazed Si3N4/42CrMo
Authors: Wang Tianpeng , Sun Mingcheng , Wang Yunan , Wang Zhongyu , Xia Yongfeng , Zhang Jie
Published: March 2024

Micron-TiN particles and Ti powder were introduced into the AgCu powder filler to design a particle-reinforced composite filler. This TiN particle (TiNp) modified brazing material was adopted to reliably braze Si3N4 ceramics onto 42CrMo steel, and the ratio of active element Ti to TiNp reinforcement was optimized for joint strength improvement. The reaction layer’s thickness (TiN+Ti5Si3) adjacent to the ceramic decreased by introducing TiNp. Nevertheless, the reaction layer’s thickness (TiC) at the 42CrMo side did not vary too much. TiNp showed excellent wettability with Ag-Cu-Ti braze, and there was no obvious reaction at the interface. Cu-Ti intermetallic compounds were formed and randomly distributed in the brazing seam. When the TiNp content did not exceed 8 vol.%, the joints’ mechanical properties first sharply decreased and then remained basically unchanged when Ti increased. Raising the TiNp content to 10 vol.%, the joint strength showed the changing trends of first increasing and then dropping by increasing Ti content. The bending strength reached the maximum value of 396 MPa when 8 vol.% TiNp and 4 wt.% Ti were adopted.
Preparation and performance study of anti mud polycarboxylic acid slump retaining agent
Authors: Xiong Qiumin , Chen Xiaobin , Qiu Nianli , Xu Meizhou , Yang Xianxian
Published: March 2024

Anti-mud polycarboxylic acid slump retaining agent was prepared by copolymerization of ethylene glycol monovinyl polyethylene glycol ether, diethyl 4-vinylphenyl phosphate, 2-methyl-2-(4-vinylphenyl) propionic acid, unsaturated carboxylic acid (or unsaturated carboxylic anhydride) and unsaturated carboxylic ester under the action of initiator and molecular weight regulator. The effect of the slump retaining agent on the workability of fine aggregate concrete with different mud contents was tested, and the sensitivity of the slump retaining agent to the mud content of machine-made sand was evaluated. At the same time, the viscosity reduction performance of the slump retaining agent was evaluated by using the emptying time of the inverted slump cone and the flow time of V-funnel and L-box. The experimental results show that the synthesized anti-mud polycarboxylic acid slump retaining agent has favourable effects of anti-mud and viscosity reduction.
Effect of V-N alloying on mechanical properties of HRB400E
Authors: Pang Zhuochun , Zhu Fei , Li Huicheng , Yuan Jing , Wang Haixin
Published: March 2024

V-N alloying is used to improve the mechanical properties of HRB400E steel for construction. The research shows that the adding number of 0.025% V and 0.0080% N can achieve the solidification micro-structure of rolled steel, significantly improve the strength of steel, but also bring the toughening effect, which can reach this yield strength of 430 MPa and its tensile strength of 650 Pa.
Highly Trans-1,4-selective Coordination Polymerization of Polar 2-(2-Fluorophenyl)-1,3-butadiene Catalyzed by Monofluorene Rare-Earth Metal Complexes
Authors: Wang Mingqi , Lu Yongqiu , Ye Yanchun
Published: March 2024

The preparation of high trans-1,4-structure functionalized polyconjugated dienes by high-position/stereoregularity coordination polymerization of polar conjugated dienes can effectively introduce some heteroatom groups into synthetic rubbers. It can not only effectively improve the performance of synthetic rubber but also develop new functional polyconjugated diene materials to broaden its application range. The coordination polymerization reaction of the polar diene 2-(2-fluorophenyl)-1,3-butadiene (o-FBD) with high trans-1,4-structure (95%) has been achieved firstly by using monofluorene scandium rare-earth metal complexes (1-6) activated by co-catalyst system [B(C6F5)4][Ph3C] and Al
i
Bu3, and a plastic polymer P(o-FBD) is obtained, which has a high molecular weight (up to 10.6 × 104g·mol−1) and glass transition temperature from 16.8°C to 22.6°C.
NC/Co@NC catalyst with hollow structure accelerates lithium-sulfur battery reaction kinetics
Authors: Wei Hualiang , Chen Zexiang , Lv Huifang , Zhao Yang , Bao Mengyao , Yu Ke , Guo Xiaowei , Wang Yan
Published: March 2024

Lithium-sulfur (Li-S) batteries have gained significant interest due to their impressive energy density. Nonetheless, poor conductivity and shuttle effect hamper their further development. Here, we prepared NC/Co@NC catalyst materials by a self-templating method to improve the battery performance. The ZIF-8@ZIF-67@PDA was initially prepared by utilizing the favorable compatibility between ZIF and dopamine, and subsequently annealed to form NC/Co@NC materials. The NC/Co@NC catalyst can effectively adsorb lithium polysulfides (LiPSs), lower the reaction barrier and accelerate its conversion to lithium sulfide (Li2S). Moreover, the configuration of the hollow structure enhances the catalyst-electrolyte interface, which can maximize the catalytic ability of NC/Co@NC. The improved ion diffusion rates benefiting from the hollow structure can also be realized. With these combined effects, Li-S cells incorporating the NC/Co@NC hollow catalysts achieved a high sulfur utilization and superior rate behaviour, that is 1176 and 470 mAh g−1 at 0.2 and 4C, respectively. Furthermore, the cells achieved an ultralow capacity degradation of merely 0.08% per cycle after 300 cycles at 1C, further confirming their potential.
High cis-1,4-selectivity and activity coordination (co) polymerization of (polar) dienes by PNP-ligated rare-earth metal bis (aminobenzyl) complexes
Authors: Pei Jingting , Fu Zhijie , Li Xiaofang
Published: March 2024

The research on the synthesis of cis-1,4-selective poly (conjugated diene)s catalyzed by the transition metal complexes has been actively pursued in both industrial and academic laboratories until today. However, there has not been any reported rare-earth catalytic system that can achieve the cis-1,4-selective polymerization of multiple conjugated dienes. Polar and non-polar conjugated dienes, as well as copolymerization of different kinds of conjugated dienes affording novel copoly (diene)s, are included. Herein, the highly cis-1,4-selective homopolymerization of a series of (polar)dienes (such as IP, MY, OC, 2-MOPB, 2-FPB) was achieved by using PNP ligated rare-earth metal bis (aminobenzyl) complexes PNP-Ln (Ln = Ln = Sc, Lu, Y, Gd, Sm, 1-5)/[Ph3C][B(C6F5)4]/Al
i
Bu3 ternary catalyst systems. Moreover, the highly cis-1,4-selective copolymerization of (polar)dienes (such as 2-MOPB and IP, 2-FPB and IP, MEPB and IP, OC and IP as well as 2-FPB and MY) with a board range of comonomers contenting and random or block sequence distribution was also achieved.
A Density Functional Theory Investigation of Cleavage Mechanism of Dimethylsulphoniopropionate by Lyase DddQ
Authors: Wu Hanxiao , Zhang Xuewei
Published: March 2024

Dimethylsulfide (DMS) is released from the dimethylmercaptopropionate (DMSP) lyase decomposition reaction, which is of great significance for the global sulfur cycle. Among the various DMSP lyases, DddQ is one of the most prevalent and effective enzymes, catalyzing the conversion of DMSP into DMS. Using density functional calculations, we performed a detailed investigation of the DddQ reaction employing a concerted β-elimination mechanism via Tyr131 or Tyr120 as a general base. The reaction involves several key processes, including the deprotonation of nucleophile base, hydrogen proton transfer on Cα, and Cβ-S bond cleavage. Notably, the Hα proton transfer step is a critical step in determining the reaction rate in both mechanisms.
Kinetic analysis of pyrolysis of nitrocellulose and 5,5’-bistetrazole-1,1’-diolate (TKX-50)
Authors: Zhang Zilu , Xu Bin
Published: March 2024

For the sake of exploring the decomposition characteristics and kinetic of nitrocellulose and TKX-50 mixtures, Friedman, KAS, and OFW kinetic analysis methods were used to investigate the mixture of nitrocellulose and TKX-50 mixtures. It shows that nitrocellulose and TKX-50 promote each other during the thermal decomposition process. Therefore, this study provides a reference for NC-A and TKX-50 in the application field of explosives.
Quantum chemical study on non-thermal plasma degradation tar in gasification syngas
Authors: Liang Hanzhao , Li Zhigang , Kuang YunKun , Nong Jinlong , Wei Yuwei , Li Yongjun , Lin Qingyu , Pan Zhi , Zhang Zanzan , Huang Qinghua , Lu Jie
Published: March 2024

The bond dissociation energies (BDEs) of benzene, toluene, and naphthalene which are the main components of tar in fluidized bed gasification syngas have been investigated by B3LYP method at 6-31G (d, p), 6-31G+ (d, p), 6-31G++ (d, p) and 6-311G++ (d, p) basis setsof density functional theory (DFT).The structures of benzene, toluene, naphthalene, and corresponding radicals were optimized, and their total energiesand zero-point energies (ZPE) were calculated.The frequency analysis was carried out, then, the transition state and the high order saddle were excluded, and the influence of zero point energy scaling factors was neglected.The results showed thatthe BDEs decreased with increasing computational basis sets. The calculated results obtained by B3LYP/6-31G (d, p) are much closer to the results of the documents than the other three basis sets. This indicates that the basis set of B3LYP/6-31G (d, p) is much more credible in reproducing the BDEs. The lowest electron energy values for the ring opening of benzene, toluene and naphthalene are 8.05 eV, 7.45 eV, and 7.35 eV, respectively, indicating that when the energy of high-energy electrons reaches 8.05 eV, the ring of aromatic hydrocarbon can be broken.
A novel molecular imprinted electrochemical biosensor for sensitive determination of Ganoderic acid A
Authors: Li Wenwei , Xie Yao , Liang Axin
Published: March 2024

Analytical approaches with the features of easy manipulation, cost-effectiveness, and miniature are needed for practice-oriented point-of-care diagnostics. This work prepared the molecularly imprinted polymers (MIPs) to selectively detect Ganoderic acid A (GAA). To determine the optimum composition, we examined diverse functional monomers through batch rebinding experiments. The new method uses nanomaterials-functionalized screen-printed carbon electrode (SPCE) to selectively measure GAA, the critical ingredient in Ganoderma lucidum (G. lucidum). Reduced graphene oxide (RGO) chitosan attached to SPCEs has offered the electrochemical sensor core to detect GAA. Cyclic voltammetry (CV) was performed on the SPCE to electropolymerize MIP using a solution containing GAA with o-phenylenediamine being the template. Thereafter, this sensor was characterized by scanning electron microscopy (SEM), and CV together with electrochemical impedance spectroscopy (EIS). GAA was analyzed through differential pulse voltammetry (DPV) within the 0.1-100 ng/mL linear range, and the limit of detection (LOD) was 0.03 ng/mL. The sensor’s simplicity, selectivity, and environmental friendliness make it ideal to detect GAA.
Time error accumulation in a hierarchical time and clock distribution network with deterministic optical links
Authors: Sidorenko V. , Müller W.F.J. , Emschermann D. , Zabolotny W. , Fröhlich I. , Becker J. ,   the CBM collaboration
Published: March 2024

Accurate clock and time distribution is a key requirement for self-triggered streaming data acquisition in the CBM experiment. This distribution is handled by the Timing and Fast Control (TFC) system by clock forwarding and broadcasting the common time over latency-deterministic optical links in a hierarchical FPGA network. The point-to-point optical connections are served by the latency-optimized GBT-FPGA core, which has been developed at CERN. In the presented work, the performance of GBT-FPGA links for time and clock distribution in a scaled TFC system with multiple hops and endpoints has been investigated.
The quality control programme for ITk strip tracker module assembly
Authors: Tishelman-Charny A. ,   the ATLAS ITk collaboration
Published: March 2024

The assembly of the ATLAS Inner Tracker requires the construction of 19,000 silicon strip sensor detector modules in eight different geometries. Modules will be assembled and tested at 31 institutes on four continents from sensors, readout chips, and flexes. In order to adhere to the module specifications defined for sufficient tracking performance, a rigorous programme of quality control (QC) was established to cover components at every stage of assembly. This contribution presents an overview of the QC programme for ITk strip tracker modules, issues encountered during the pre-production phase (5% of the production volume), and their solutions.
First results on MPGD prototypes in test beam for MPGD-based HCAL at a future Muon Collider experiment
Authors: Colaleo A. , Buonsante M. , Longo L. , Maggi M. , Pellecchia A. , Radogna R. , Simone F.M. , Stamerra A. , Venditti R. , Verwilligen P.J. , Zaza A. ,   the International Muon Collider collaboration
Published: March 2024

The Multi-TeV Muon Collider will allow significant advancement in particle physics and in the understanding of its Standard Model for the era after the High-Luminosity LHC. The Muon Collider physics program involves precise Higgs boson sector measurements and TeV-scale new physics exploration. These goals demand accurate full-event reconstruction. The Particle Flow algorithm, which utilizes tracking, calorimeter, and muon detectors, is ideal for identifying and precisely estimating particle momenta/energies and can accomplish this task. Tracking detectors measure charged particle momenta, while calorimeters provide energy measurements for photons and neutral hadrons. Therefore, combining an exceptional tracking system with high-granularity calorimeters is essential. A major challenge is discerning μμ collision products from beam-induced-background, due to muon decay. To address this, an innovative hadronic calorimeter (HCAL) using Micro Pattern Gas Detectors (MPGDs) is proposed. MPGDs provide robust technology for high radiation and ensure precise spatial measurements. Dedicated studies are needed to assess and optimize the performance of an MPGD-based HCAL, including the development of medium-scale prototypes for performance measurements.
This article describes the studies for a hadronic calorimeter based on MPGDs, relying on advanced technologies such as μ-rwell, resistive MicroMegas, and RPWELL. To assess the performance of MPGD detectors, a test beam was conducted in July 2023 at the Super Proton Synchrotron at CERN. This test beam aimed to evaluate the performance of MPGD detectors with 1×1 cm2 pad readout under beam irradiation. Preliminary results from this test are presented.
The BMS group in D = 6 spacetime dimensions
Authors: Fuentealba Oscar , Henneaux Marc
Published: March 2024

The asymptotic structure of gravity inD = 6 spacetime dimensions is described at spatial infinity in the asymptotically flat context through Hamiltonian (ADM) methods. Special focus is given on the Bondi–Metzner–Sachs (BMS) supertranslation subgroup. It is known from previous studies that the BMS group contains more supertranslations as one goes fromD = 4 toD = 5. Indeed, while the supertranslations are described by one single function of the angles inD = 4, four such functions are neeeded inD = 5. We consider the caseD = 6 with the aim of determining whether the number of supertranslations keeps increasing with the dimension or remains equal to the number found inD = 5. We show that even though there is apparent room for more supertranslations, their number remains equal to theD = 5 value (four): the potentially new supertranslations turn out to define proper gauge transformations corresponding to a redundancy in the description of the system. Critical in the analysis are the boundary conditions chosen to yield a well-defined canonical formalism. Given the computational (but not conceptual) complexity as one increases the dimension, we explicitly discuss the linearized theory and argue that asymptotically, this analysis provides the correct picture. We conclude by considering higher spacetime dimensions where we indicate that the number of physically relevant supertranslations remains equal to four independently of the dimension⩾5.

Contribution to Stanley Deser memorial volume ‘Gravity, Strings and Beyond’
Assessment of machinability behaviour of LM24 – nano Al2O3 – gr hybrid composites through stir casting technique
Authors: Surendran R , Kumaravel A
Published: March 2024

This study is focused on developing a novel combination of a hybrid MMC made of LM24 aluminium alloy, nano Al2O3 and Graphite for enhanced machinability. The study conducts a series of experimental runs and evaluates surface roughness and material removal rate. The process parameters of spindle speed, feed, and depth of cut have been varied, while different weight percentages of nano Al2O3 (1%, 3%, and 5%) were incorporated into the LM24 metal matrix alloy along with 1 wt% of Gr. Response Surface Methodology (RSM) is used to optimize the turning parameters and enhance the machining performance for better quality and productivity. The derived optimal machining parameters have been verified through confirmatory tests. An analysis of variance (ANOVA) was used to determine the individual contributions of each parameter to the machinability characteristics. Surface morphology analysis revealed the uniform distribution of nanoparticle reinforcements in the metal matrix. The surface roughness and material removal rate of the machined nanocomposites were studied. The optimized outputs are a minimum surface roughness Ra 0.522 μm and maximum material removal rate MRR 110.2 mm3s–1 The maximum hardness of the MMC composites has been 60.5 HRB.
Electronic structure control of IrO2 via conjugated polymer support for highly efficient oxygen evolution reaction
Authors: Asai Yusaku , Higashimine Koichi , Nishimura Shun , Badam Rajashekar , Matsumi Noriyoshi
Published: March 2024

In this paper, we report synthesis of novel nanoparticle catalyst of iridium oxide supported on conjugated polymer along with evaluation of activity and durability for oxygen evolution reaction. The IrO2/poly(BIAN-thiophene)/TNT catalyst was prepared from iridium complex and poly(BIAN-thiophene)/TNT by hydrothermal method. The synthesized IrO2/poly(BIAN-thiophene)/TNT catalysts was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transfer-infrared spectroscopy, x-ray photoelectron spectroscopy and electrochemical methods. The average particle size of the IrO2 particles on poly(BIAN-thiophene)/TNT was 2.5 nm. The XPS measurement revealed that Ir complex was completely converted to iridium oxide through hydrothermal treatment. The IrO2/poly(BIAN-thiophene)/TNT catalyst showed sufficient performance for OER activity and durability in acidic condition. Our results indicate that IrO2/poly(BIAN-thiophene)/TNT is one of the prospective candidate catalysts for water splitting.
Exploring nonlinear and linear optical properties of N, N’-bis(salicylidene)-o-phenylenediamine (salophen) through Z-scan technique and TD-DFT computational analysis
Authors: Abed Yasaman , Mostaghni Fatemeh , Abed Niloofar
Published: March 2024

This investigation delves into the comprehensive analysis of the linear and nonlinear optical characteristics exhibited by N, N’-bis(salicylidene)-o-phenylenediamine (salophen) using a combination of Z-scan methodology and quantum chemistry calculations. The Z-scan technique facilitated meticulous computations of the third-order susceptibility, nonlinear absorption coefficient, and nonlinear refractive index of the specimen. Specifically, in the solvent DMSO, the assessed values for the nonlinear refractive index, nonlinear absorption coefficient, and third-order susceptibility were determined to be 0.035 × 10–10 cm2
W

−1
, −0.024 × 10–5 cm W

−1
, and 0.596 × 10–5 esu, respectively. Furthermore, quantum mechanical analyses were employed to meticulously calculate the molecular hyperpolarizabilities (β and γ), dipole moment (μ), and dipole polarizability (α) of salophen. This thorough exploration highlighted a notable congruence between the outcomes derived from experimental observations and those obtained through quantum mechanical simulations. The collective findings from both theoretical computations and experimental assessments distinctly showcase the robust nonlinear potential inherent in salophen. These insights suggest its promising suitability and potential as a viable candidate for applications in optical devices. The alignment between theoretical predictions and experimental results underlines the reliability and potential practicality of salophen in the realm of optical technology, emphasizing its significance as a potential material for advancing optical device functionalities.
Mathematical modeling in assessing the risk of restenosis after carotid endarterectomy
Authors: Borisov V G , Zakharov Yu N , Vinogradov R A , Derbilova V P , Ivanova N V
Published: March 2024

Carotid endarterectomy is the main way to combat atherosclerosis of the carotid arteries, which disrupts cerebral circulation. The generally accepted marker of atherogenesis risk are hemodynamic indices associated with near-wall shear stress. The purpose of the work is to conduct a comparative analysis of hemodynamic indices in various carotid bifurcation models. The influence of a virtual change in the geometric shape of the model in order to optimize hemodynamic indices is also being studied. On the basis of computed angiography data, carotid bifurcation models are constructed, in which critical zones of hemodynamic indices are built using computational fluid dynamics. A comparative analysis of the critical zones for different classes of models is carried out. Comparison of averaged indices for critical zones between ‘normal’ and post-operative groups gave more than 5-x worse results for the latter. The same results for the near-bifurcation parts of the zones give a 25% better result for postoperative models. Virtual ‘removal’ of insignificant plaques leads to a deterioration of the indices of up to 40% in the places of the plaque’s former location. The described method makes it possible to build the indices critical zones and compare them for various types of models. A technique for virtual changing the shape of a vessel (virtual surgery) is proposed. The novelty of the approach lies in the use for comparative analysis both real vessel models and hypothetical ‘improved’ virtual ones, as well in the proposed division of post-operative model’s critical zones into subzones of different genesis.
Viruses change structure at human body temperatures to infect us better
Authors: Dumé Isabelle
Published: March 2024

The structure of viral DNA has been uncovered in unprecedented detail, shedding new light on changes that make the macromolecule more fluid-like at temperatures close to that of the human body.
Panel calls for muon collider
Authors: Allen Michael
Published: March 2024

The “P5” panel of US particle physicists say that work on developing a future muon collider could allow the US regain the “energy frontier”, as Michael Allen reveals.
Ukraine invasion forced a fifth of scientists to flee
Authors: van Woerkom Ethan
Published: March 2024

An investigation by Swiss and Ukrainian researchers has found that almost 20% of scientists in Ukraine fled the country by the end of 2022 as a result of the Russian invasion.
Polarized transport requires AP-1-mediated recruitment of KIF13A and KIF13B at the trans-Golgi
Authors: Montgomery Andrew C. , Mendoza Christina S. , Garbouchian Alex , Quinones Geraldine B. , Bentley Marvin
Published: March 2024

Neurons are polarized cells that require accurate membrane trafficking to maintain distinct protein complements at dendritic and axonal membranes. The Kinesin-3 family members KIF13A and KIF13B are thought to mediate dendrite-selective transport, but the mechanism by which they are recruited to polarized vesicles and the differences in the specific trafficking role of each KIF13 have not been defined. We performed live-cell imaging in cultured hippocampal neurons and found that KIF13A is a dedicated dendrite-selective kinesin. KIF13B confers two different transport modes, dendrite- and axon-selective transport. Both KIF13s are maintained at the trans-Golgi network by interactions with the heterotetrameric adaptor protein complex AP-1. Interference with KIF13 binding to AP-1 resulted in disruptions to both dendrite- and axon-selective trafficking. We propose that AP-1 is the molecular link between the sorting of polarized cargoes into vesicles and the recruitment of kinesins that confer polarized transport.
Federalism in Drag
Authors: Bascom Ben
Published: March 2024

This chapter turns to a forgotten figure of eighteenth-century market capitalism who amassed wealth through a chance speculation. To do so, it draws upon drag’s insights on performance and campiness—its aesthetics of imitation and parody—to consider how this self-declared aristocrat, “Lord” Timothy Dexter, seeks inclusion within a Federalist New England as he negotiates his relation to early U.S. market capitalism soon after the Constitution. Dexter commissioned life-size wooden statues of various new republic figures, including himself, and decorated his front lawn with them, thus trying to insert himself into the emerging pantheon of the new nation’s figures of cultural significance.
The Queer Hermit
Authors: Bascom Ben
Published: March 2024

The final chapter examines how the story of an alleged eighteenth-century infanticide by Elizabeth Wilson and her public execution became transformed into a narrative, and a religious tract, about the executed woman’s brother. William “Amos” Wilson became “a recluse from the jars of a contending world” after failing to save his sister from a public execution in 1786. He left behind a life narrative, entitled The Sweets of Solitude (1821), that demonstrates changing notions regarding masculinity in the public sphere. The text of the hermit’s narrative quotes from eighteenth-century translations of Seneca, representing the modern, public world as corrupt and degraded. Because these quotes are not acknowledged in the text, I argue that the narrative resembles a commonplace book with unattributed aphorisms that suggest the depersonalization of republican masculinity.
Preparation Sessions
Authors: Brennan Bill , Belser Alex
Published: March 2024

Chapter 5 outlines a preparation phase consisting of three 90-minute nondrug sessions. Preparation lays the groundwork for potential benefits across the six EMBARK domains. The therapist’s aims in this phase include building trust, understanding the participant’s experience of depression, identifying participant intentions, and providing psychoeducation about psychedelic therapy. The chapter provides concrete instructions for the preparation sessions in each of the six EMBARK clinical domains. For example, the therapist: (E) aims to create an environment that encourages profound spiritual experiences; (M) teaches techniques for compassionate internal focus and self-soothing; (B) fosters an appreciation for somatic practices; (A) encourages the participant to openly receive their emotions and beliefs; (R) strives to cultivate a therapeutic relationship characterized by safety, acceptance, and empowerment while considering the participant’s trauma history and cultural context; and (K) codevelops strategies to promote continuity of therapeutic gains. Three session agendas are provided.
Secret origins: the disavowal of the comics medium within the promotional rhetoric of film trailers
Authors: Grosvenor Chris
Published: March 2024

Predicated upon a corpus of 4,200 films, this article documents, analyses, and interprets the international film industry’s rhetorical disavowal of the comic book medium as a source for adaptation within advertising and promotional rhetoric for the cinematic adaptation of comic book texts. By analysing the statistical trends and patterns for comic book adaptations between 2000 and 2020, examining the language used within promotional trailers to conceptualise or promote the feature adaptation in relation to their comic book source material, and by comparing the type and scope of this rhetoric with other adapted texts of the same period, this article evidences and interrogates the overwhelming disavowal of the comic book medium despite the persistent and widely perceived ubiquity of comic book adaptation franchises. Above all, this article utilises statistical evidence and analysis to evidence clear patterns and trends within the perceived hierarchies of cultural taste or artistic value.
Cracking the black box of deep sequence-based protein–protein interaction prediction
Authors: Bernett Judith , Blumenthal David B , List Markus
Published: March 2024

Identifying protein–protein interactions (PPIs) is crucial for deciphering biological pathways. Numerous prediction methods have been developed as cheap alternatives to biological experiments, reporting surprisingly high accuracy estimates. We systematically investigated how much reproducible deep learning models depend on data leakage, sequence similarities and node degree information, and compared them with basic machine learning models. We found that overlaps between training and test sets resulting from random splitting lead to strongly overestimated performances. In this setting, models learn solely from sequence similarities and node degrees. When data leakage is avoided by minimizing sequence similarities between training and test set, performances become random. Moreover, baseline models directly leveraging sequence similarity and network topology show good performances at a fraction of the computational cost. Thus, we advocate that any improvements should be reported relative to baseline methods in the future. Our findings suggest that predicting PPIs remains an unsolved task for proteins showing little sequence similarity to previously studied proteins, highlighting that further experimental research into the ‘dark’ protein interactome and better computational methods are needed.
The role of the indoleamine 2,3-dioxygenase gene in preventing ovarian transplant rejection in rats
Authors: Long Aizhuan , Zhao Shuyun , Huang Guanyou , Li Xiaoying , Cheng Hui , Chen Zengchunxiao , Hu Zhu , Zhu Leilei , Zhao Danqing , Hu Xiaoyan , Wang Jun
Published: March 2024

Indoleamine 2,3-dioxygenase (IDO) plays important roles in maternal immune tolerance. Female Sprague Dawley rats (9–11 weeks old) were randomly divided into an autoplastic transplantation group (n = 75) and an allograft transplantation group (n = 300) was further divided into subgroups of ovarian transplantation, allograft ovarian transplantation, allograft ovarian transplantation with cyclosporine A treatment, allograft ovarian transplantation and transfection with IDO-expressing lentiviruses, and allograft ovarian transplantation and transfection with control lentiviruses. IDO was successfully transfected into the transplanted ovarian tissue. The survival rate, success rate of ovarian transplantation, period until estrous cycle restoration, and estrogen levels of rats that received IDO-expressing lentiviruses were significantly different from those of rats that underwent allograft transplantation and with control transfection (all P < 0.05), but not significantly different from those rats that received autoplastic transplantation (all P > 0.05). The number of ovarian follicles in the transplanted ovarian tissue of rats that received IDO-expressing lentiviruses was also significantly higher. The expression level of IDO protein detected by immunohistochemistry and western blotting was especially high in ovaries that had received IDO-containing lentiviruses. Naturally pregnant rats were found in each group postoperatively. These results indicated that IDO-expressing lentiviruses were successfully transfected into transplanted ovarian tissues of rats and that IDO was stably expressed within a certain time. These findings suggest that the expression level of IDO protein is associated with an enhanced success rate of ovarian tissue transplantation and a short restoration period of endocrine function.
The role of remnant cholesterol in patients with ST-segment elevation myocardial infarction
Authors: Zhou Yan , Madsen Jasmine Melissa , Özbek Burcu Tas , Køber Lars , Bang Lia Evi , Lønborg Jacob Thomsen , Engstrøm Thomas
Published: March 2024

Aims

Remnant cholesterol (RC) is the cholesterol content within triglyceride-rich lipoproteins. It promotes atherosclerotic cardiovascular disease beyond LDL cholesterol (LDL-C). The prognostic role of RC in patients with ST-segment elevation myocardial infarction (STEMI) is unknown. We aimed to estimate RC-related risk beyond LDL-C in patients with STEMI.

Methods and results

A total of 6602 consecutive patients with STEMI treated with primary percutaneous coronary intervention (PCI) from 1999 to 2016 were included. Remnant cholesterol was calculated as total cholesterol minus LDL-C minus HDL cholesterol. Adjusted Cox models were used to estimate the association between continuous RC levels and all-cause mortality, cardiovascular death, ischaemic stroke, and recurrent myocardial infarction (MI) at long-term (median follow-up of 6.0 years). Besides, discordance analyses were applied to examine the risk of the discordantly high RC (RC percentile rank minus LDL-C percentile rank > 10 units) compared with the discordantly low RC (LDL-C percentile rank minus RC percentile rank > 10 units). The concordance was defined as the percentile rank difference between RC and LDL-C ≤ 10 units. The median age of patients was 63 years [interquartile range (IQR) 54–72] and 74.8% were men. There were 2441, 1651, and 2510 patients in the discordantly low RC group, concordant group, and discordantly high RC group, respectively. All outcomes in the discordantly high RC group were higher than the other groups, and the event rate of all-cause mortality in this group was 31.87%. In the unadjusted analysis, the discordantly high RC was associated with increased all-cause mortality [hazard ratio (HR) 1.82, 95% confidence interval (CI) 1.63–2.04] and increased cardiovascular death (HR 1.79, 95% CI 1.55–2.06) compared with the discordantly low RC. In an adjusted model, RC was associated with higher all-cause mortality (HR 1.14, 95% CI 1.07–1.22). The discordantly high RC was associated with increased all-cause mortality (adjusted HR 1.55, 95% CI 1.37–1.75) and increased cardiovascular death (adjusted HR 1.47, 95% CI 1.25–1.72) compared with the discordantly low RC. There were no associations between RC and ischaemic stroke or recurrent MI.

Conclusion

In patients with STEMI treated with primary PCI, elevated RC levels beyond LDL-C and discordantly high RC were independently associated with increased all-cause mortality.
Fas2EB112: a tale of two chromosomes
Authors: Finegan Tara M , Cammarota Christian , Mendoza Andrade Oscar , Garoutte Audrey M , Bergstralh Dan T
Published: March 2024

The cell–cell adhesion molecule Fasciclin II (Fas2) has long been studied for its evolutionarily conserved role in axon guidance. It is also expressed in the follicular epithelium, where together with a similar protein, Neuroglian (Nrg), it helps to drive the reintegration of cells born out of the tissue plane. Remarkably, one Fas2 protein null allele, Fas2G0336, demonstrates a mild reintegration phenotype, whereas work with the classic null allele Fas2EB112 showed more severe epithelial disorganization. These observations raise the question of which allele (if either) causes a bona fide loss of Fas2 protein function. The problem is not only relevant to reintegration but fundamentally important to understanding what this protein does and how it works: Fas2EB112 has been used in at least 37 research articles, and Fas2G0336 in at least three. An obvious solution is that one of the two chromosomes carries a modifier that either suppresses (Fas2G0336) or enhances (Fas2EB112) phenotypic severity. We find not only the latter to be the case, but identify the enhancing mutation as Nrg14, also a classic null allele.
Repeated Hyposalinity Pulses Immediately and Persistently Impair the Sea Urchin Adhesive System
Authors: Garner Austin M , Moura Andrew J , Narvaez Carla A , Stark Alyssa Y , Russell Michael P
Published: March 2024

Synopsis

Climate change will increase the frequency and intensity of extreme climatic events (e.g., storms) that result in repeated pulses of hyposalinity in nearshore ecosystems. Sea urchins inhabit these ecosystems and are stenohaline (restricted to salinity levels ∼32‰), thus are particularly susceptible to hyposalinity events. As key benthic omnivores, sea urchins use hydrostatic adhesive tube feet for numerous functions, including attachment to and locomotion on the substratum as they graze for food. Hyposalinity severely impacts sea urchin locomotor and adhesive performance but several ecologically relevant and climate change-related questions remain. First, do sea urchin locomotion and adhesion acclimate to repeated pulses of hyposalinity? Second, how do tube feet respond to tensile forces during single and repeated hyposalinity events? Third, do the negative effects of hyposalinity exposure persist following a return to normal salinity levels? To answer these questions, we repeatedly exposed green sea urchins (Strongylocentrotus droebachiensis) to pulses of three different salinities (control: 32‰, moderate hyposalinity: 22‰, severe hyposalinity: 16‰) over the course of two months and measured locomotor performance, adhesive performance, and tube foot tensile behavior. We also measured these parameters 20 h after sea urchins returned to normal salinity levels. We found no evidence that tube feet performance and properties acclimate to repeated pulses of hyposalinity, at least over the timescale examined in this study. In contrast, hyposalinity has severe consequences on locomotion, adhesion, and tube foot tensile behavior, and these impacts are not limited to the hyposalinity exposure. Our results suggest both moderate and severe hyposalinity events have the potential to increase sea urchin dislodgment and reduce movement, which may impact sea urchin distribution and their role in marine communities.
Seasonal Variations in the Toughness of Leaves: A Case Study Using Griselinia littoralis
Authors: Taylor David
Published: March 2024

Synopsis

Potential effects of climate change include greater extremes of temperature and increased severity of storms. Many plants have evolved to resist the challenges of winter (freezing, dehydration, and wind) in a process known as cold hardening. Sensing reducing temperatures, they make structural changes at the cellular level to increase their mechanical resistance and prevent damage. Previous work on this topic, though extensive, has been conducted under laboratory conditions rather than in the field, and while many workers have observed changes to cell wall thickness and composition, which imply increased mechanical strength, few have actually measured strength or any other parameter describing structural integrity. This paper describes experiments on a model system designed to measure the structural integrity of leaf laminae from plants growing naturally in the field over extended periods, allowing seasonal variations to be captured. Standard engineering properties—tensile strength and fracture toughness—were measured for leaves of Griselinia littoralis on 19 separate occasions over a 12-month period. Toughness (rather than strength) was found to be the controlling mechanical property. Toughness values were found to change significantly during the year, by more than a factor of 2. Toughness correlated strongly with average daily soil temperature, but with a lag of about 1–2 weeks, suggesting that this is the time needed for structural adjustments to take place. Highest toughness values occurred in winter, confirming cold hardening. Increasing temperature in the spring was associated with decreasing toughness, but in the summer, when highest temperatures occurred, toughness increased again. This apparent “hot hardening” may be a response to dehydration. Results imply that a given leaf is able to both increase and decrease its toughness in response to temperature changes, demonstrating excellent plasticity of response. This case study of a single species establishes a method of reliably measuring changes in a plant’s structural integrity due to cold hardening and other seasonal variations, which may be used to investigate the effects of climate change and other variables.
High niche specificity and host genetic diversity of groundwater viruses
Authors: Gios Emilie , Mosley Olivia E , Hoggard Michael , Handley Kim M
Published: March 2024

Viruses are key members of microbial communities that exert control over host abundance and metabolism, thereby influencing ecosystem processes and biogeochemical cycles. Aquifers are known to host taxonomically diverse microbial life, yet little is known about viruses infecting groundwater microbial communities. Here, we analysed 16 metagenomes from a broad range of groundwater physicochemistries. We recovered 1571 viral genomes that clustered into 468 high-quality viral operational taxonomic units. At least 15% were observed to be transcriptionally active, although lysis was likely constrained by the resource-limited groundwater environment. Most were unclassified (95%), and the remaining 5% were Caudoviricetes. Comparisons with viruses inhabiting other aquifers revealed no shared species, indicating substantial unexplored viral diversity. In silico predictions linked 22.4% of the viruses to microbial host populations, including to ultra-small prokaryotes, such as Patescibacteria and Nanoarchaeota. Many predicted hosts were associated with the biogeochemical cycling of carbon, nitrogen, and sulfur. Metabolic predictions revealed the presence of 205 putative auxiliary metabolic genes, involved in diverse processes associated with the utilization of the host’s intracellular resources for biosynthesis and transformation reactions, including those involved in nucleotide sugar, glycan, cofactor, and vitamin metabolism. Viruses, prokaryotes overall, and predicted prokaryotic hosts exhibited narrow spatial distributions, and relative abundance correlations with the same groundwater parameters (e.g. dissolved oxygen, nitrate, and iron), consistent with host control over viral distributions. Results provide insights into underexplored groundwater viruses, and indicate the large extent to which viruses may manipulate microbial communities and biogeochemistry in the terrestrial subsurface.