bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction, structural modification, and bioactivity evaluation of pentacyclic triterpenoid privileged scaffolds in active natural products
Authors: Zeng Ling Rong , Pan Bo Wen , Cai Juan , Liu Li Juan , Dong Zhang Chao , Zhou Ying , Feng Ting Ting , Shi Yang
Published: December 2024

Pentacyclic triterpenoids, as important representatives of natural products, have garnered widespread attention due to their diverse biological activities, including anti-inflammatory, antiviral, and antitumor effects.
Redefining the roles of alkali activators for porous carbon
Authors: Zhang Yonghui , Xu Xin , Geng Qingxuan , Li Qingwei , Li Xiuli , Wang Yixuan , Tang Zihuan , Gao Biao , Zhang Xuming , Chu Paul K. , Huo Kaifu
Published: December 2024

The rough concept of alkaline strength dominating activation was furtherly clarified, and KOH and K2CO3 acted as an activation promoter and pathway modifier, respectively.
One-step synthesis of 2-cyclopentylcyclopentanone from cyclopentanone catalyzed by NiO-Co3O4/TiO2: reaction pathway
Authors: Zhang Rui , Li Danhui , Zhao Peng , Zhao Lili , An Hualiang
Published: December 2024

Reaction pathway for one-step synthesis of 2-cyclopentylcyclopentanone from cyclopentanone over NiO-Co3O4/TiO2 is first proposed. The sequence for appearance of active sites is first acid–base active sites, followed by hydrogenation active site.
Ubiquitin E3 ligases in the plant Arg/N-degron pathway
Authors: Oldham Keely E. A. , Mabbitt Peter D.
Published: December 2024

Regulation of protein longevity via the ubiquitin (Ub) — proteasome pathway is fundamental to eukaryotic biology. Ubiquitin E3 ligases (E3s) interact with substrate proteins and provide specificity to the pathway. A small subset of E3s bind to specific exposed N-termini (N-degrons) and promote the ubiquitination of the bound protein. Collectively these E3s, and other N-degron binding proteins, are known as N-recognins. There is considerable functional divergence between fungi, animal, and plant N-recognins. In plants, at least three proteins (PRT1, PRT6, and BIG) participate in the Arg/N-degron pathway. PRT1 has demonstrated E3 ligase activity, whereas PRT6 and BIG are candidate E3s. The Arg/N-degron pathway plays a central role in plant development, germination, and submersion tolerance. The pathway has been manipulated both to improve crop performance and for conditional protein degradation. A more detailed structural and biochemical understanding of the Arg/N-recognins and their substrates is required to fully realise the biotechnological potential of the pathway. This perspective focuses on the structural and molecular details of substrate recognition and ubiquitination in the plant Arg/N-degron pathway. While PRT1 appears to be plant specific, the PRT6 and BIG proteins are similar to UBR1 and UBR4, respectively. Analysis of the cryo-EM structures of Saccharomyces UBR1 suggests that the mode of ubiquitin conjugating enzyme (E2) and substrate recruitment is conserved in PRT6, but regulation of the two N-recognins may be significantly different. The structurally characterised domains from human UBR4 are also likely to be conserved in BIG, however, there are sizeable gaps in our understanding of both proteins.
Recycle, repair, recover: the role of autophagy in modulating skeletal muscle repair and post-exercise recovery
Authors: Acheson Jordan , Joanisse Sophie , Sale Craig , Hodson Nathan
Published: December 2024

Skeletal muscle is a highly plastic tissue that can adapt relatively rapidly to a range of stimuli. In response to novel mechanical loading, e.g. unaccustomed resistance exercise, myofibers are disrupted and undergo a period of ultrastructural remodeling to regain full physiological function, normally within 7 days. The mechanisms that underpin this remodeling are believed to be a combination of cellular processes including ubiquitin-proteasome/calpain-mediated degradation, immune cell infiltration, and satellite cell proliferation/differentiation. A relatively understudied system that has the potential to be a significant contributing mechanism to repair and recovery is the autophagolysosomal system, an intracellular process that degrades damaged and redundant cellular components to provide constituent metabolites for the resynthesis of new organelles and cellular structures. This review summarizes our current understanding of the autophagolysosomal system in the context of skeletal muscle repair and recovery. In addition, we also provide hypothetical models of how this system may interact with other processes involved in skeletal muscle remodeling and provide avenues for future research to improve our understanding of autophagy in human skeletal muscle.
Chromosome hitchhiking: a potential strategy adopted by the selfish yeast plasmids to ensure symmetric inheritance during cell division
Authors: Kumar Deepanshu , Ghosh Santanu Kumar
Published: December 2024

The 2-micron plasmid residing within the host budding yeast Saccharomyces cerevisiae nucleus serves as a model system for understanding the mechanism of segregation and stable maintenance of circular endogenously present extrachromosomal DNA in eukaryotic cells. The plasmid is maintained at a high average copy number (40–60 copies per yeast cell) through generations despite there is no apparent benefit to the host. Notably, the segregation mechanism of 2-micron plasmid shares significant similarities with those of bacterial low-copy-number plasmids and episomal forms of viral genomes in mammalian cells. These similarities include formation of a complex where the plasmid- or viral encoded proteins bind to a plasmid- or viral genome-borne locus, respectively and interaction of the complex with the host proteins. These together form a partitioning system that ensures stable symmetric inheritance of both these genomes from mother to daughter cells. Recent studies with substantial evidence showed that the 2-micron plasmid, like episomes of viruses such as Epstein–Barr virus, relies on tethering itself to the host chromosomes in a non-random fashion for equal segregation. This review delves into the probable chromosome hitchhiking mechanisms of 2-micron plasmid during its segregation, highlighting the roles of specific plasmid-encoded proteins and their interactions with host proteins and the chromosomes. Understanding these mechanisms provides broader insights into the genetic stability and inheritance of extrachromosomal genetic elements across diverse biological systems.
Research on a high‐performance signal distribution reconstruction algorithm for wireless communication networks
Authors: Li Zhimeng , Wang Hongjun , Shen Zhexian
Published: December 2024

With the rapid development of communication technology and the increasing demand for coverage refinement in wireless communication networks, the optimization of wireless communication networks is faced with unprecedented challenges. Obtaining the signal distribution map of wireless communication networks efficiently has become a popular area of study in this field. This paper considers a distributed sensing network architecture, a radial basis function neural network is used to process electromagnetic data and optimize the parameters of the random forest model. Then, interpolation processing of incomplete electromagnetic data is achieved by the improved random forest model, based on which a signal distribution map of the wireless communication network is reconstructed. The results indicate that the proposed algorithm yields high interpolation accuracy. The average error between the real signal distribution and the reconstructed signal distribution is 2.7973 dBm when the proportion of sampled nodes is 1%, and the similarity of the reconstructed signal distribution map to the original signal distribution map is good, demonstrating certain application prospects.
Experimental study on temperature control of cable tunnel fire under the combined effect of fine water mist and mechanical ventilation
Authors: Zhu Hui , Ji Jun , Nie Jingkai , Xia Yu
Published: December 2024

Electricity is an important energy supply for industry, and long‐distance transmission in China mainly relies on cable tunnels, while cable tunnel fires occur frequently. A 1:1 scale tunnel model with a length of 20 m, a width of 2.5 m, and a height of 2.5 m was used to conduct experimental research on the temperature field of the ceiling of a high‐voltage fine water mist suppression cable tunnel. The article conducted experimental research on parameters, such as nozzle pressure, nozzle position, and longitudinal ventilation speed in high‐pressure water mist systems using n‐hexane as the ignition source. The results indicate that the high‐pressure water mist system can effectively reduce the ceiling temperature during cable tunnel fires. When the mechanical smoke evacuation system is activated, it leads to a reduction in the overall temperature within the tunnel. When the mechanical smoke extraction system is integrated with the high‐pressure water mist system, therefore, it is feasible to integrate the high‐pressure water mist system with the mechanical smoke exhaust system in engineering applications.
PlutoNet: An efficient polyp segmentation network with modified partial decoder and decoder consistency training
Authors: Erol Tugberk , Sarikaya Duygu
Published: December 2024

Deep learning models are used to minimize the number of polyps that goes unnoticed by the experts and to accurately segment the detected polyps during interventions. Although state‐of‐the‐art models are proposed, it remains a challenge to define representations that are able to generalize well and that mediate between capturing low‐level features and higher‐level semantic details without being redundant. Another challenge with these models is that they are computation and memory intensive, which can pose a problem with real‐time applications. To address these problems, PlutoNet is proposed for polyp segmentation which requires only 9 FLOPs and 2,626,537 parameters, less than 10% of the parameters required by its counterparts. With PlutoNet, a novel decoder consistency training approach is proposed that consists of a shared encoder, the modified partial decoder, which is a combination of the partial decoder and full‐scale connections that capture salient features at different scales without redundancy, and the auxiliary decoder which focuses on higher‐level semantic features. The modified partial decoder and the auxiliary decoder are trained with a combined loss to enforce consistency, which helps strengthen learned representations. Ablation studies and experiments are performed which show that PlutoNet performs significantly better than the state‐of‐the‐art models, particularly on unseen datasets.
Large disturbance stability analysis method for DC microgrid with virtual DC motor control
Authors: Zhao Fengzhan , Liu Ting , Ju Yuntao , Li Hong
Published: December 2024

Mixed potential theory is frequently employed for analysing large‐disturbance stability. The precision of the current stability criterion for DC microgrids controlled by virtual DC motors (VDCM), which relies on mixed potential theory, is inadequate. This is primarily because the criterion does not account for the control parameters of the DC bus voltage control link and the virtual DC motor link. To address these issues, the paper initially formulates the control aspect of the VDCM using a controlled current source. Subsequently, it derives the system's mixed potential function from the model, enabling the development of a stability criterion that includes the control parameters of the DC bus voltage control link, the virtual DC motor link, and the current tracking link. It also clarifies how parameters not directly included in the criterion affect system stability. Through simulations and experimental validations, it is demonstrated that the proposed stability criterion effectively captures the impact of control parameters on system stability and precisely delineates the system's power stability boundary, offering insights for system parameter optimization.
Hydrodynamical simulations with strong indirect terms in FARGO-like codes
Authors: Jordan Lucas M. , Rometsch Thomas
Published: December 2024

Context. Binary star systems allow us to study the planet formation process under extreme conditions. In the early stages, these systems contain a circumbinary disk and a disk around each star. To model the interactions between these disks in the frame of one of the stars, strong fictitious forces must be included in the simulations. The original FARGO and the FARGO3D codes fail to correctly simulate such systems if the indirect term becomes too strong.

Aims. We present a different way to compute the indirect term that, together with a tensor artificial viscosity prescription, allows the FARGO code to simulate the circumbinary disks in a non-inertial frame of reference. In this way, the FARGO code can be used to study interactions between circumstellar and circumbinary disks.

Methods. We first evaluated the accuracy of the standard implementation and our proposed indirect term prescription using a simple N-body test case. We then analytically estimated the effect of the default artificial viscosity used in the FARGO code in the limit of large distances to the N-body system. Finally, we evaluated the effects of the different prescriptions by performing hydrodynamical simulations in a non-inertial frame of reference.

Results. By updating the indirect term prescription and the artificial viscosity, we were able to successfully simulate a circumbinary disk in a frame that is centered on the less massive star. We find that updating the indirect term becomes relevant when the indirect term becomes stronger than the direct gravitational forces, which occurs for mass ratios of q ≳ 5%. The default artificial viscosity used in the FARGO code inherently produces artificial pressure in a non-inertial frame of reference even in the absence of shocks. This leads to artificial mass ejection from the Hill sphere, starting at brown dwarf masses (q ≳ 1%). These problems can be mitigated by using a tensor artificial viscosity formulation. For high mass ratios, q ≳ 1%, it is also becomes important to initialize the disk in the center-of-mass frame. We expect our proposed changes to be relevant for other grid-based hydrodynamic codes where strong indirect terms occur, or for codes that use artificial viscosity.
Confirmation of four hot Jupiters detected by TESS using follow-up spectroscopy from MaHPS at Wendelstein together with NEID and TRES
Authors: Ehrhardt Juliana , Thomas Luis , Kellermann Hanna , Freitag Christine , Grupp Frank , Yee Samuel W. , Winn Joshua N. , Hartman Joel D. , Collins Karen A. , Watkins Cristilyn N. , Stassun Keivan G. , Benni Paul , Bieryla Allyson , Carden Kylee , Checinski Jacek , Cheryasov Dmitry V. , Diamond Brendan , Dowling Nicholas , Dressing Courtney D. , Esparza-Borges Emma , Evans Phil , Forés-Toribio Raquel , Fukui Akihiko , Giacalone Steven , Girardin Eric , Goeke Robert F. , Goessl Claus , Hayashi Yuya , Hopp Ulrich , Jenkins Jon M. , Khan Isa , Laloum Didier , Lark Adam , Latham David W. , de Leon Jerome , Marchini Alessandro , Massey Bob , Muñoz Jose A. , Murgas Felipe , Narita Norio , Palle Enric , Papini Riccardo , Parviainen Hannu , Pippert Jan-Niklas , Popowicz Adam , Pritchard Tyler , Quinn Samuel N. , Raetz Manfred , Ries Christoph , Riffeser Arno , Savel Arjun B. , Seager Sara , Schmidt Michael , Striegel Stephanie , Srdoc Gregor , Stockdale Chris , Verna Gaia , Watanabe David , Ziegler Carl , Zöller Raphael
Published: December 2024

We report the confirmation and characterization of four hot Jupiter-type exoplanets initially detected by TESS: TOI-1295 b, TOI-2580 b, TOI-6016 b, and TOI-6130 b. Using observations with the high-resolution echelle spectrograph MaHPS on the 2.1 m telescope at Wendelstein Observatory, together with NEID at Kitt Peak National Observatory and TRES at the Fred Lawrence Whipple Observatory, we confirmed the planetary nature of these four planet candidates. We also performed precise mass measurements. All four planets are found to be hot Jupiters with orbital periods between 2.4 and 4.0 days. The sizes of these planets range from 1.29 to 1.64 Jupiter radii, while their masses range from 0.6 to 1.5 Jupiter masses. Additionally, we investigated whether there are signs of other planets in the systems but have found none. Lastly, we compared the radii of our four objects to the results of an empirical study of radius inflation and see that all four demonstrate a good fit with the current models. These four planets belong to the first array of planets confirmed with MaHPS data, supporting the ability of the spectrograph to detect planets around fainter stars as faint as V = 12.
Molecular gas budget of strongly magnified low-mass star-forming galaxies at cosmic noon
Authors: Catán V. , González-López J. , Solimano M. , Barrientos L. F. , Afruni A. , Aravena M. , Bayliss M. , Hernández J. A. , Ledoux C. , Mahler G. , Sharon K. , Tejos N.
Published: December 2024

Aims. The aim of this study is to investigate the molecular gas content of strongly magnified low-mass star-forming galaxies (SFGs) around the cosmic noon period (z ∼ 2) through observations of carbon monoxide (CO) emission lines and dust continuum emission, both of which serve as tracers of molecular gas (H2).

Methods. We observed 12 strongly lensed arcs with the Atacama Compact Array (ACA) to detect CO mid-J rotational transitions and dust continuum. Thanks to the strong lensing, we were able to probe the previously understudied low-mass regime. With a compiled set of observations, we recalibrated empirical relations between star formation rate density (ΣSFR) and the CO line ratios. We derived galaxy properties using spectral energy distribution fitting (SED). We also performed galaxy stacking to combine faint signals. In all cases, molecular gas masses were estimated using both tracers.

Results. We detected CO emission in 3 of the 12 arcs and dust continuum emission in another 3. The obtained H2 masses indicate that most of these galaxies (M* < 1010.7 M⊙) have lower molecular gas fractions and shorter depletion times compared to expectations from established scaling relations at these redshifts. We explored several possible explanations for this gas deficit, including uncertainties in mass estimates, effects of low-metallicity environments, larger atomic gas reservoirs in low-mass systems, and the possibility that these represent low-mass analogs of main sequence starburst (MS SBs) galaxies that are undergoing sustained star formation due to gas compaction despite low overall gas fractions.

Conclusions. We conclude that these mass and metallicity regimes present a molecular gas deficit. Our results suggest that this deficit is likely due to a significant amount of atomic gas, which our stacking indicates is about 91% of the total gas. However, this estimation might be an upper limit, as the possibility remains that our galaxies contain CO-dark gas.
Photometric analysis of 40 low mass-ratio contact binary systems in the Catalina Sky Survey
Authors: Wang JinLiang , Ding Xu , Liu Wei , Yu LiHuan , Xu Chong , Ji KaiFan
Published: December 2024

Low mass-ratio contact binary systems are a fascinating class of eclipsing binaries; they are widely regarded as the potential progenitors of stellar mergers. For this study we analyzed 40 newly discovered low mass-ratio totally eclipsing contact binary systems identified from the Catalina Sky Survey data. The relative parameters for these systems were inferred using a neural network model combined with a Bayesian inference-based Hamiltonian Monte Carlo (HMC) algorithm, with uncertainties estimated from the posterior distributions generated by the HMC algorithm. The absolute parameters were then calculated using these relative parameters, along with distances and temperatures provided by Gaia Data Release 3. Among the 40 systems, 24 are deep low mass-ratio overcontact binaries, characterized by fill-out factors of 0.5 or higher and mass ratios of 0.25 or lower. Notably, two systems, CSS_J071952.5+243224 and CSS_J155519.0+135855, have mass ratios below 0.1, specifically 0.094 ± 0.006 and 0.086 ± 0.004, respectively. Furthermore, we compared the parameters obtained in this study with those from 39 low mass-ratio contact binary systems identified in previous research, finding that the estimated parameters are largely consistent. Finally, to evaluate the evolutionary status of the 40 systems, we calculated the ratio of spin angular momentum to orbital angular momentum for each and found that all are currently in a relatively stable evolutionary phase.
The inner logic and integration path of new quality productivity and vocational education counselor construction
Authors: Yan Tang
Published: December 2024

This paper explores the intrinsic connection and integration path between new quality productivity and the construction of vocational education counselors. As the driving force of modern industry, new quality productivity puts forward new requirements for vocational education. As a key role, counselors need to adapt to the development of new quality productivity and improve their professional quality. The article analyzes the logic of mutual promotion between the two, extracts successful experiences through case studies, studies the links that need to be improved, and proposes integration paths such as building professional standards, strengthening the understanding of new quality productivity, innovating education models, deepening school-enterprise cooperation, and strengthening innovation and entrepreneurship capabilities. In summary, the construction of vocational education counselors under the background of new quality productivity will continue to move towards new heights and contribute greater strength to vocational education and economic and social development.
Physiotherapiewissenschaft umfassend verstehen: Ein angewandter Überblick über verschiedene Forschungsparadigmen (Teil 2)
Authors: Haase Laura A. , Bopp Katharina , Maric Filip
Published: December 2024

Die internationale Gesundheits- und Physiotherapieforschung hat sich in den letzten Jahrzehnten durch den Gebrauch und die Weiterentwicklung verschiedenster wissenschaftstheoretischer Grundlagen vielfältig entwickelt. Dadurch wird aktuellen Fragen und Problemstellungen auf unterschiedliche Weise begegnet und aktiv zur Veränderung beigetragen. Im deutschsprachigen Raum ist diese Vielfalt der wissenschaftstheoretischen Arbeit noch nicht im selben Grade zu verzeichnen. Die übliche Unterscheidung in quantitative und qualitative Forschung trägt zu Missverständnissen bei, wodurch die in diesen Begriffen implizierte Vielfalt sowohl für die Theorieentwicklung als auch für die angewandte Forschung verloren geht.

In einem zweiteiligen Artikel wird ein Überblick über die in der internationalen Gesundheits- und Physiotherapieforschung gängigsten Forschungsparadigmen gegeben, um deren grundlegendes Verständnis und zukünftige Anwendung in der deutschsprachigen Physiotherapiewissenschaft zu fördern.

Im ersten Teil wurden zunächst wichtige begriffliche Grundlagen geklärt. Darauf aufbauend wurde der Positivismus und Interpretativismus vorgestellt, darunter insbesondere deren ontologische, epistemologische und methodologische Grundannahmen und die sich aus diesen ergebenden praktischen Möglichkeiten. Diese Möglichkeiten wurden anhand plakativer Forschungsfragen zum Thema der Akademisierung veranschaulicht, und es wurde damit begonnen, die Notwendigkeit paradigmatischer Vielfalt in der Physiotherapieforschung zu verdeutlichen.

Im vorliegenden zweiten Teil werden auf dieselbe Weise das kritische Paradigma und der Poststrukturalismus erläutert. Das führt zu einer abschließenden Diskussion der Limitationen des Artikels sowie der Bedeutung von verschiedenen Forschungsparadigmen für den wissenschaftlichen Diskurs in der Physiotherapie. Dabei wird deutlich, dass die Akademisierung eine Voraussetzung dafür ist, dass die Physiotherapie überhaupt einen aktiven Bezug zur Wissenschaft haben kann. Dieser zweiteilige Beitrag liefert einen ersten Einstieg in die weitere Auseinandersetzung mit wissenschaftstheoretischen Grundlagen und der Anwendung und Weiterentwicklung verschiedenster Forschungsparadigmen, die es braucht, um den komplexen sozialen, ökologischen und gesundheitsrelevanten Problemen der aktuellen Zeit gerecht zu werden.
The Association between Perinatal Complications and Adverse Childhood Experiences: Findings from a Nationwide Online Survey
Authors: Imanishi Yousuke , Wada Ichiro , Tabuchi Takahiro
Published: December 2024

Objective This study aimed to evaluate the association between maternal adverse childhood experiences (ACEs) levels and the risk of perinatal complications.

Study Design This is a retrospective cohort study of 5,693 mother–child pairs born between 2019 and 2021, who completed questionnaires on maternal ACE scores and perinatal complications such as preterm birth, low birth weight infants, pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), and premature rupture of membrane (PROM). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression according to the three ACE score groups after adjusting for confounding factors such as maternal age, child's sex, household income, and maternal education.

Results Maternal ACEs have a significant positive correlation with preterm birth (OR: 1.42, 95% CI: 1.09–1.86, p for trend = 0.009), PIH (OR: 1.55, 95% CI: 1.17–2.07, p for trend = 0.002), and PROM (OR: 1.42, 95% CI: 1.09–1.84, p for trend = 0.01). These associations remained unchanged when stratified according to smoking, alcohol consumption, and obesity.

Conclusion Maternal ACEs were associated with the risk of perinatal complications such as preterm birth, PIH, and PROM.

Key Points
Development of a Triethylborane-Mediated Giese Cyclization/Aldol Reaction Cascade for the Total Synthesis of Ganoapplanin
Authors: Müller Nicolas , Kováč Ondřej , Magauer Thomas , Rode Alexander , Atzl Daniel
Published: December 2024

We present our synthetic endeavors towards the Ganoderma meroterpenoid ganoapplanin. This natural product was isolated from a Ganoderma fungus in 2016 and was found to be an inhibitor for T-type voltage-gated calcium channels. Our synthetic approach is based on a powerful intramolecular Giese cyclization/intermolecular aldol cascade to link the northern aromatic to the southern terpenoid fragment. This article highlights the synthetic studies that ultimately led to the successful development of the key cascade reaction, culminating in the first total synthesis of ganoapplanin.

1 Introduction

2 Synthesis of the Southern Terpenoid Fragment

3 Synthesis of the Northern Terpenoid Fragment

4 Triethylborane-Mediated Giese Cyclization/Aldol Reaction Cascades

5 Completion of the Total Synthesis of Ganoapplanin

6 Conclusion
Transition-Metal-Catalyzed Asymmetric Reduction of 2-Pyridine Ketones
Authors: Ollevier Thierry , Vasudevan Vidhul , Harishankar M S
Published: December 2024

This graphical review provides a concise overview of transition-metal-catalyzed asymmetric reduction of 2-pyridine ketones to produce enantiopure chiral 2-pyridine aryl/alkyl alcohols, which are present in many chiral ligands and pharmaceuticals. Key methods include metal-catalyzed hydrogenation, transfer hydrogenation, and hydrosilylation, with a focus on sustainable catalysts like iron and manganese. This review serves as a foundation for future advancements in sustainable and enantioselective keto group reductions.
A Revised Protecting Group Strategy Enables a Divergent Synthesis of Prenylated Isoflavones from Psoralea corylifolia
Authors: Kwesiga George , Schmidt Bernd , von Chamier Gliszczinski Sarah , Sperlich Eric , Kelling Alexandra
Published: December 2024

Three bioactive prenylated isoflavone natural products were synthesized for the first time, using a combination of Pd-catalyzed Suzuki–Miyaura coupling for installing the B-ring, microwave-promoted Claisen rearrangement of allyl ethers, and Ru-catalyzed olefin cross metathesis for obtaining the prenyl substituents. Careful consideration of the protecting group strategy turned out to be vital for the success of these total syntheses.
Normative Ranges for Oculomotor and Reaction Time Tests in U.S. Military Service Members and Veterans
Authors: Talian Daniel S. , Eitel Megan M. , Zion Danielle J. , Kuchinsky Stefanie E. , French Louis M. , Brickell Tracey A. , Lippa Sara M. , Lange Rael T. , Brungart Douglas S.
Published: December 2024

Background Oculomotor and reaction time tests are frequently used assessments of vestibular symptoms, traumatic brain injury (TBI), or other neurological disorders in both clinical and research contexts. When interpreting these tests it is important to have a reference interval (RI) as a comparison for what constitutes a typical/expected response; however, the current body of research has only limited information regarding normative ranges calculated according to established standards or for a military-specific sample.

Purpose The purpose of the present study was to describe RIs for oculomotor and reaction time tests in a cohort of service members and veterans (SMVs) for use as comparators by clinicians and scientists.

Research Design Descriptive.

Study Sample Participants were prospectively enrolled in the Defense and Veterans Brain Injury Center-Traumatic Brain Injury Center of Excellence 15-year Longitudinal Traumatic Brain Injury Study. Only SMVs without a history of TBI or blast exposure were included in the RI calculations.

Data Collection and Analysis The test paradigms included in this analysis were: smooth pursuit, prosaccades, antisaccades, saccades and reaction time, predictive saccades, optokinetic nystagmus, auditory reaction time, and visual reaction time. Nonparametric methods, based on the U.S. Food and Drug Administration's recognized consensus standards, were used to calculate 95% RIs. A comparison between the calculated RIs and those available from previously published research is provided.

Results Summary statistics and RIs were calculated for 47 outcome parameters from 13 oculomotor and reaction time tests. Sample sizes and age ranges varied across outcome parameters depending on the availability of reference values for RI calculations. The sample sizes used to calculate RIs ranged from 51 to 69. The age of SMVs included in each RI ranged from 19 to 61 years with mean ages ranging from 37 to 39 years. Similarities/differences between the RIs in the present study and those in previously published research are highly dependent on the outcome parameter; however, in general, the RIs in the present study tended to be somewhat wider.

Conclusion The RIs provided in this paper can serve as comparisons for clinicians and scientists who are utilizing these oculomotor and reaction time testing paradigms in similar cohorts of patients or research participants.
The European Diploma in Musculoskeletal Radiology: Webinar Program of the ESSR
Authors: Rupreht Mitja , Weber Marc-André , Drakonaki Elena , Martinoli Carlo , Vanhoenacker Filip , Robinson Philip , Adriaensen Miraude
Published: December 2024

The European Diploma in Musculoskeletal Radiology (EDiMSK) is a recognized European qualification of excellence for musculoskeletal (MSK) radiologists. Webinars have become a vital component of electronic learning. This article introduces European Society of Musculoskeletal Radiology members to its webinar program that offers an additional source of direct interactive learning from renowned MSK radiologists. These webinars contribute to Continuing Medical Education and assist in preparing for the EDiMSK exam. We discuss the concept, history, and organization of the webinars.
Trends of Mortality due to Traumatic Brain Injury in the USA: A Comprehensive Analysis of CDC WONDER Data from 1999 to 2020
Authors: Shafique Muhammad Ashir , Mustafa Muhammad Saqlain , Kumar Aashish , Iqbal Javed , Haseeb Abdul , Rahman Hafsah Alim Ur , Mussarat Abdullah , Rangwala Burhanuddin Sohail , Rangwala Hussain Sohail , Ali Syed Muhammad Sinaan , Ashraf Mohammad
Published: December 2024

Traumatic brain injury (TBI) poses a significant public health challenge in the United States, with diverse causes and outcomes. Understanding the trends in TBI-related mortality is crucial for effective prevention and intervention strategies. This comprehensive analysis utilized data from the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research (CDC WONDER) database, covering the period from 1999 to 2020. Cause-of-death records were examined using the 10th Edition of the International Classification of Diseases and Related Health Problems diagnostic code S06 for TBI-related fatalities. Mortality rates were calculated per 100,000 individuals, adjusted for age and urban/rural status. Joinpoint Regression analysis was employed to identify significant trends over time. Between 1999 and 2020, 1,218,667 TBI-related deaths occurred, with varying mortality rates across demographic groups and geographic regions. Within the overall population, the highest annual average mortality rates were observed in the non-Hispanic (NH) American Indian or Alaska Native cohort, followed by NH white, NH black or African American, Hispanic or Latino, and NH Asian or Pacific Islander groups. Overall, there was an initial decrease in mortality rate from 1999 to 2012, followed by a subsequent significant increase. Males consistently exhibited higher mortality rates than females across all age groups. Disparities were also observed based on race/ethnicity, with NH American Indian or Alaska Native populations showing the highest mortality rates. Regional variations were evident, with the southern region consistently exhibiting the highest mortality rates. Evolving trends in TBI-related mortality in the United States highlight the need for targeted interventions, particularly in high-risk demographic groups and regions.
8.1.35 Use of Organolithiums in Flow Chemistry
Authors: Miyagishi H. V. , Nagaki A.
Published: December 2024

Organolithium reagents are essential compounds for organic synthesis. Their potent reactivity, as both strong bases and nucleophiles, allows them to react with various organic compounds, facilitating the synthesis of desired organic molecules. However, their extremely high reactivity often results in low stability, restricting the variety of organolithium reagents that are suitable for organic synthesis. The high reactivity also impairs their chemical compatibility and selectivity, limiting the utility of organolithium reagents in the synthesis of functionalized molecules. Therefore, methodology for taming the excessive reactivity of organolithium reagents is in high demand. In this review, we discuss the use of flow microreactors as a tool to address these problems. Organolithium species, excluding heterocycles, are classified into five categories, and their generation and application using flow microreactors is comprehensively discussed. In particular, the section on aryllithium compounds provides a detailed discussion of the exploitation of unstable organolithiums and the effect of the use of flow technology on chemical compatibility and selectivity. The flow microreactors discussed herein have significantly expanded the scope of application of organolithium species.
8.1.33.4 Transition-Metal-Catalyzed C—C Bond Formation with Organolithium Reagents (Update 2025)
Authors: Mateos-Gil J. , Fañanás-Mastral M.
Published: December 2024

Organolithium compounds are among the most versatile and widely used reagents in organic synthesis. However, their high reactivity and basicity have historically limited their use as direct coupling partners in metal-catalyzed carbon—carbon bond forming methods. This review provides an update to the advances in this area, with a focus on highlighting reports during the period 2011–2023, that have revolutionized the field, propelling organolithium reagents to the forefront of strategies for constructing new C—C bonds using transition-metal catalysts.
9.8.17 Four-Membered Rings with One or More Heteroatoms (Update 2025)
Authors: Didier D. , Trauner F. , Jiang D.
Published: December 2024

Fully unsaturated four-membered heterocycles, like their carbocyclic analogues, are classes of compounds that remain scarce in the literature when compared to other cyclic molecular motifs. This is mainly due to their antiaromatic properties, which make them unstable unless stabilized through coordination. Rare examples have, however, been characterized as intermediates in synthesis or even isolated as pure compounds. The first part of this review discloses recent advances in the synthesis of monoheteroatomic compounds such as azetes, thietes, siletes, and λ3- or λ5-phosphetes (depending on the oxidation state of the phosphorus atom), and is an update to the previous Science of Synthesis contribution on this topic (Section 9.8). The second part of this review describes the synthesis of structures containing more than one heteroatom in the core ring and is organized following the atomic number of the heaviest heteroatom.
Analog model for scalar dynamics in a Kerr–Sen background
Authors: Schmidt Alexandre G. M. , Pereira Matheus E.
Published: December 2024

Black holes (BH) are challenging as objects of study and measurement. The extreme conditions they produce make direct observation a formidable task. Here we provide an analog model to the dynamics of a charged scalar particle in the background of a Kerr–Sen BH, which comes from a string theory metric. This model consists in a particle constrained to move on a spherical surface that may rotate and may be in the presence of an electromagnetic field. We show that a charged scalar particle in our analog model produces the exact same dynamics of a dilaton in the Kerr–Sen space. The functions that describe the dynamics are written as confluent Heun’s functions, also match the original system.
Flow-induced frequency shifts in suspended microchannel resonators with ultra-thin walls and large hydraulic diameter
Authors: Sharma Samridh , Arun Chandorkar Saurabh
Published: December 2024

A suspended microchannel resonator (SMR) is an unconventionally designed microelectromechanical system mass sensor that allows internal fluid flow in its suspended structure. This device is operated at its resonance conditions and registers a frequency shift corresponding to the mass flowing through the channel. Presented here is a dynamic SMR fluid–structure phenomenon that has not been reported to date. SMR devices were fabricated with ultra-thin walls and large hydraulic diameter using thermo-compression wafer bonding, and optical characterization of these SMRs with internal fluid flow using a laser Doppler vibrometer revealed frequency shifts of various vibration modes with variation in fluid flow rate, gas species, and device geometry. The underlying physics is modeled semi-analytically and is found to match some of the experimental observations, while others are unanticipated. This study shows that SMRs can be used to sense flow rate by measuring the change in resonant frequency resulting from the flow, aside from standard Coriolis-based measurement. Furthermore, it is shown that fluctuations in fluid flow due to inlet pressure noise create noise in the frequency measurement, which, in turn, sets the resolution that can be achieved in mass sensing.
Phase transitions in anisotropic turbulence
Authors: van Kan Adrian
Published: December 2024

Turbulence is a widely observed state of fluid flows, characterized by complex, nonlinear interactions between motions across a broad spectrum of length and time scales. While turbulence is ubiquitous, from teacups to planetary atmospheres, oceans, and stars, its manifestations can vary considerably between different physical systems. For instance, three-dimensional turbulent flows display a forward energy cascade from large to small scales, while in two-dimensional turbulence, energy cascades from small to large scales. In a given physical system, a transition between such disparate regimes of turbulence can occur when a control parameter reaches a critical value. The behavior of flows close to such transition points, which separate qualitatively distinct phases of turbulence, has been found to be unexpectedly rich. Here, we survey recent findings on such transitions in highly anisotropic turbulent fluid flows, including turbulence in thin layers and under the influence of rapid rotation. We also review recent work on transitions induced by turbulent fluctuations, such as random reversals and transitions between large-scale vortices and jets, among others. The relevance of these results and their ramifications for future investigations are discussed.
Response of ferroelectric nanodomain to alternative-current electric fields in morphotropic-phase boundary Pb(Mg1/3Nb2/3)O3−PbTiO3
Authors: Sato Yukio
Published: December 2024

The single crystal of morphotropic-phase-boundary (MPB) Pb(Mg1/3Nb2/3)O3−PbTiO3 (PMN-PT) is widely utilized in ultrasonic medical imaging devices due to its excellent piezoelectric properties. In recent years, alternating-current (AC) poling has proven effective in enhancing these properties, though AC poling beyond optimal cycles can lead to deterioration. In this study, to gain deeper insights into the mechanisms driving the change of piezoelectricity, the response of ferroelectric domains in an MPB PMN–PT single crystal was examined using in situ AC field electrical biasing transmission electron microscopy. The ferroelectric domain structure was significantly altered by applying a single cycle of an AC electric field at 12 kV/cm peak-to-peak and 20 Hz. Subsequently, with increased AC field duration, both a reduction in domain wall density and the generation of vertical microdomain bands were observed. These phenomena could, respectively, enhance and degrade the piezoelectricity of the material.
Removability of the fundamental singularity for the heat equation and its consequences
Authors: Abdulla Ugur G.
Published: December 2024

We prove the necessary and sufficient condition for the removability of the fundamental singularity, and equivalently for the unique solvability of the singular Dirichlet problem for the heat equation. In the measure-theoretical context the criterion determines whether the h-parabolic measure of the singularity point is null or positive. From the probabilistic point of view, the criterion presents an asymptotic law for conditional Brownian motion.
Quasiperiodic shrimp-shaped domains in intrinsically coupled oscillators
Authors: de Souza Silvio L. T. , Batista Antonio M. , Medrano-T Rene O. , Caldas Iberê L.
Published: December 2024

We report remarkable pattern formation of quasiperiodic domains in the two-dimensional parameter space of an intrinsically coupled system, comprising a rotor and a Duffing oscillator. In our analysis, we characterize the system using Lyapunov exponents, identifying self-similar islands composed of intricate regions of chaotic, quasiperiodic, and periodic behaviors. These islands form structures with an accumulation arrangement, denominated here as metamorphic tongues. Inside the islands, we observe Arnold tongues corresponding to periodic solutions. In addition, we surprisingly identify quasiperiodic shrimp-shaped domains that have been typically observed for periodic solutions. Similar features to the periodic case, such as period-doubling and secondary-near shrimp with three times the period, are observed in quasiperiodic shrimp as torus-doubling and torus-tripling.
Influence of debris-flow property on the uplift pressure of closed check dam
Authors: Sun Hao , Zhang Li , You Yong , Liu Jinfeng , Shang Yuqi , Wang Dongwei
Published: December 2024

Uplift pressure is a critical vertical load on check dam foundations, playing a pivotal role in dam structural design and stability. However, the characteristic of uplift pressure remains a complex and not fully understood. In this study, a specialized test device was designed; 36 tests were conducted to simulate the uplift pressure of closed check dams under varying debris flow conditions. The formation and evolution of uplift pressure were analyzed, along with the influences of debris flow bulk density and fine particle contents. Results indicate peak uplift pressure head decreases with increasing bulk density and fine particle content, initially at rapid rate then stabilizes gradually. The peak uplift pressure decreases rapidly with increasing density at low densities (1.1–1.3 g/cm3) and then slows at higher densities (1.4–1.6 g/cm3), forming a “flat.” However, the peak uplift pressure curve for P0.1 = 10% does not show this pattern, and the changing trend of density does not form a flat. Peak uplift pressure of dilute debris flow mainly results from permeability produced by hydraulic diffusion, while for viscous debris flow, it arises from excess pore water pressure. A calculation method for the peak uplift pressure reduction coefficient was proposed. The findings comprehensively improve the understanding of the action mechanism and evolution process of uplift pressure, enhancing the performance of check dams for disaster prevention and mitigation.
Wake-induced response of vibro-impacting systems
Authors: Chawla Rohit , Rounak Aasifa , Bose Chandan , Pakrashi Vikram
Published: December 2024

The effects of a rigid barrier on the stability of the structure while it is undergoing phase-locked motions due to the surrounding fluid–structure interactions, are studied. The primary structure and the near wake dynamics are modeled as a harmonic oscillator and a Van der Pol oscillator, respectively, and are weakly coupled via acceleration coupling. Qualitative changes in the dynamical behavior of this system are investigated in the context of discontinuity-induced bifurcations that result from the interaction of fluid flow and nonsmoothness from the impact of the primary structure. Phenomenological behaviors like the co-existence of attractors and period-adding cascades of limit cycles separated by chaotic orbits are observed. The behavior of orbits in the local neighborhood of the discontinuity boundary is defined using a higher-order transverse discontinuity map, and the corresponding stability analysis is carried out using Floquet theory. The derived mapping is implemented to obtain the respective Lyapunov exponents. Results obtained using the mapping are demonstrated to accurately predict both the stable and chaotic regimes, as observed from the corresponding numerical bifurcation diagrams.
Skeletal structure in domain of periodicity of the forced Brusselator
Authors: Maranhão Dariel M. , Medrano-T Rene O.
Published: December 2024

We report the peculiar organization of oscillations in the forced Brusselator system, found in the parameter space as a nested structure of regular and chaotic phases. To this end, we apply the winding number concept, conceived for nonlinear driven oscillators, to expose all oscillatory phases in the nested structure. First, we use the period and torsion of orbits to describe every periodic oscillation in the parameter spaces, describing the nested structure in high-resolution phase diagrams. Next, we propose a basic structure organizing the periodicity, a “skeletal set” whose properties elucidate the genealogy and composition of oscillations in the nested structure. Finally, we discuss the application of the skeletal structure in a diversity of Brusselator’s oscillatory regimes.