bluuebunny/crossref_metadata_2025 huggingface dataset:
A Dual Column pH Switchable Water Stationary Phase System for Separation Control in Supercritical Fluid Chromatography
Authors: Nai Emmanuel A. , Thurbide Kevin B.
Published: November 2024

A dual column system comprised of a pH switchable water stationary phase column and a conventional non‐polar capillary column is introduced for use in Supercritical Fluid Chromatography (SFC). By removing or adding NH4OH to the system hydration source, the water stationary phase pH can be rapidly switched between acidic (measured at pH∼3) and basic (measured at pH∼9) in seconds, while the operating character of the conventional column is unchanged. This switch modulates the velocity of ionizable analytes about 20‐fold in the system, whereas non‐ionizable analytes are not affected. In this way, the retention time of acids and/or bases can be reproducibly altered (<1% RSD; n = 3) in SFC separations. As a result, analyte selectivity and resolution can be readily controlled during analyses. For example, a selectivity reversal (alpha from 0.4 to 1.6) and a resolution increase (from 0 to 13) are demonstrated. Rapid stationary phase pH switching also allows multiple acids, bases, and/or neutral analytes to be determined simultaneously. Applications demonstrate that this method can greatly simplify complex mixture analysis in SFC by helping to separate target analytes from interfering matrix components.
Preparation and Application of Weak Cation Exchange Resin Based on Thiol Click Reaction
Authors: Huang Zhongping , Zhu Qingqing , Han Yu , Mo Ying , Zhang Junhao , Liu Huijun
Published: November 2024

Using poly(styrene‐divinylbenzene) microspheres as stationary phase matrix and mercaptosuccinic acid as a modifier, a new weak cation exchange resin was synthesized by thiol click reaction. The conditions for thiol‐chlorine click reaction and thiol‐alkene click reaction were optimized. The surface morphology and chemical composition of the modified microspheres were characterized by scanning electron microscopy, Fourier‐transform infrared spectroscopy, and an elemental analyzer. The stationary phase can achieve the separation of six common cations within 25 min. A homemade weak cation chromatographic column was used to determine the impurities of Na+ and K+ and the content of tetramethylammonium ions in tetramethylammonium hydroxide samples. The method showed a good linear correlation in the range of 0.1–500.0 mg/L with correlation coefficients of 0.9998–0.9999, and the limits of detection (signal‐to‐noise ratio ≥ 3) were 0.01–0.20 mg/L. The intra‐day relative standard deviations (RSDs) were in the range of 1.1%–4.4%, and the inter‐day RSDs were in the range of 0.8%–14.8%. The spiked recoveries were in the range of 91.92%–119.86%. The results showed that the prepared stationary phase exhibited effective separation ability and good reproducibility, which was suitable for the analysis of the impurities of Na+, K+, and the content of tetramethylammonium in the tetramethylammonium reagents.
Rapid Determination of Galantamine in Human Plasma by Microchip Electrophoresis With a Highly Integrated Contactless Conductivity Detector
Authors: Li Zhilei , Lin Gangyuan , Yang Xiujuan
Published: November 2024

A novel and rapid method was developed for the determination of galantamine in human plasma by microchip electrophoresis with a highly integrated contactless conductivity detector (CCD). The instrumental parameters affecting the response of the detector, such as excitation frequency and excitation voltage, were examined and optimized. The electrophoresis conditions that influenced the separation and detection of galantamine, including the composition of buffer solution, buffer pH, buffer concentration, additives, injection time, and separation voltage were systematically investigated. Under the optimal conditions, the peak height had a good linear relationship with the concentration of galantamine in human plasma from 10 to 160 µg/L, and the correlation coefficient was 0.9992, the limit of detection reached 1.1 µg/L. The recoveries were between 98.6% and 102.1%. This sensitive, rapid, and convenient method is a good alternative to existing methods for galantamine determination. Also, this highly integrated CCD holds great promise in clinical biochemical analysis.
Design of Functional Gyroid Minimal Surfaces Transporting Proton Based Solely on Surface Hopping Conduction Mechanism
Authors: Aoki Nanami , Tang Yumin , Zeng Xiangbing , Ichikawa Takahiro
Published: November 2024

Surface proton hopping conduction (SPHC) mechanisms is an important proton conduction mechanism in conventional polymer electrolytes, along with the Grotthuss and vehicle mechanisms. Due to the small diffusion coefficient of protons in the SPHC mechanism, few studies have focused on the SPHC mechanism. Recently, it has been found that a dense alignment of SO3− groups significantly lowers the activation energy in the SPHC mechanism, enabling fast proton conduction. In this study, a series of polymerizable amphiphilic‐zwitterions is prepared, forming bicontinuous cubic liquid‐crystalline assemblies with gyroid symmetry in the presence of suitable amounts of bis(trifluoromethanesulfonyl) imide (HTf2N) and water. In situ polymerization of these compounds yields gyroid‐nanostructured polymer films, as confirmed by synchrotron small‐angle X‐ray scattering experiments. The high proton conductivity of the films on the order of 10−2 S cm−1 at 40 °C and relative humidity of 90% is based solely on the SPHC mechanism.
Fundamental effects of array density and modulation frequency on image quality of diffuse optical tomography
Authors: Fan Weihao , Trobaugh Jason W. , Zhang Chengfeng , Yang Dalin , Culver Joseph P. , Eggebrecht Adam T.
Published: November 2024

Background

Diffuse optical tomography (DOT) provides three‐dimensional image reconstruction of chromophore perturbations within a turbid volume. Two leading strategies to optimize DOT image quality include, (i) arrays of regular, interlacing, high‐density (HD) grids of sources and detectors with closest spacing less than 15 mm, or (ii) source modulated light of order ∼100 MHz.

Purpose

However, the general principles for how these crucial design parameters of array density and modulation frequency may interact to provide an optimal system design have yet to be elucidated.

Methods

Herein, we systematically evaluated how these design parameters effect image quality via multiple key metrics. Specifically, we simulated 32 system designs with realistic measurement noise and quantified localization error, spatial resolution, signal‐to‐noise, and localization depth of field for each of ∼85 000 point spread functions in each model.

Results

We found that array density had a far stronger effect on image quality metrics than modulation frequency. Additionally, model fits for image quality metrics revealed that potential improvements diminish with regular arrays denser than 9 mm closest spacing. Further, for a given array density, 300 MHz source modulation provided the deepest reliable imaging compared to other frequencies.

Conclusions

Our results indicate that both array density and modulation frequency affect the spatial sampling of tissue, which asymptotically saturates due to photon diffusivity within a turbid volume. In summary, our results provide comprehensive perspectives for optimizing future DOT system designs in applications from wearable functional brain imaging to breast tumor detection.
A New qNMR Compliant Savitzky–Golay Apodization Function for Resolution Enhancement
Authors: Cobas Carlos , García‐Pulido José Antonio , Mora Paula , Selva Giovanni , Sykora Stan
Published: November 2024

In this work, we introduce a novel NMR apodization function designed to enhance spectral resolution while maintaining compatibility with qNMR standards. This function is based on a modified Savitzky–Golay filter, adapted for time‐domain application. It effectively suppresses the negative components typically associated with derivative spectra, while also ensuring the preservation of quantitative integrity in NMR analyses.
The role of wild palms in agroforestry systems in the Neotropics: A review
Authors: Andrade Viviana , Casas Alejandro , Balslev Henrik , Mora Francisco
Published: November 2024

Wild palms are among the most important plants in the Neotropics due to their wide distribution, species richness and cultural relevance for humans. In addition to their presence in forests, these plants also occur in anthropogenic systems throughout their range of distribution, but their role in these systems is often overlooked.

We explored databases of scientific publications to attain a panorama about the presence of wild palm species in agroforestry systems (AFS), their management and their role in those systems. Our keywords in the search engines were names of palm genera that occur in the Americas and types of agroforestry practices. We gathered and analysed information from 154 studies.

For each record, we registered: study sites, management actions, agroforestry practices and uses. We identified 65 species belonging to 24 genera managed in AFS, mainly including agrisilvicultural and silvopastoral systems, homegardens and agroforests.

We identified traits phylogenetically determined such as stem height, number and length of leaves, and fruit size that influence the presence of wild palms in AFS. Furthermore, we point out three major ways that favour the presence and management of palms in AFS: (1) the management of the canopy and the raise of palms in the understorey, (2) intentional enhancement or cultivation and (3) tolerance of palms during deforestation/fragmentation.

We emphasize that a change in the vision of palms as key components of agroforestry would favour future research and plans to improve their performance in these systems while ensuring their conservation.

Read the free Plain Language Summary for this article on the Journal blog.
Integrating machine learning for predicting biomechanical properties of layered manufactured bone implants
Authors: Sharma Shrutika , Sidhu Manmeet Kaur , Bansal Prateek , Nauriyal Shivansh , Gupta Vishal , Mudgal Deepa , Kheifetz Mikhail L. , Gretskiy Nikolay L. , Gubkin Sergey V.
Published: November 2024

The layered manufacturing (LM) based locking bone plates (LBPs) are highly favored for biomedical applications due to its implant customization flexibility, control over porosity, and functional parameters. Design of experiments mainly relies on predefined experimental run orders; however, machine learning (ML) can handle complex and nonlinear relationships for predicting output responses. This research investigates the application of various ML models for predicting the impact strength, torque values, and punch shear strength of poly lactic acid (PLA) based LBPs. A dataset of 100 data points for each response variable was developed, analyzing the influence of printing parameters, like infill density (ID), layer height (LH), wall thickness (WT), and print speed (PS). The ID, LH, WT, and PS were varied within the ranges of 20%–100%, 0.1–0.5 mm, 0.4–1.2 mm, and 20–100 mm/s, respectively. Among the ML models evaluated, XGBoost and Adaboost exhibited strong alignment of the predicted values with actual values. The decision tree regression, showed the lowest predictive accuracy due to its tendency to overfit and lack of iterative refinement. The findings suggest that ML models can effectively predict the mechanical properties of PLA‐based LBPs, offering valuable insights for optimizing printing parameters to enhance the performance of orthopedic implants. The findings can guide biomedical engineers in making data‐driven decisions to enhance the strength of LBPs, thereby improving patient outcomes in orthopedic treatments.

Highlights

Predicted impact strength, torque, and shear strength of biomedical specimens.

Evaluated 100 data points per variable to assess printing parameters' influence.

XGBoost and Adaboost showed superior accuracy, with R2 consistently above 0.9.

Decision Tree regression exhibited the lowest accuracy due to overfitting issues.

Aims to guide biomedical engineers in data‐driven decisions for better patient outcomes.
Glass machining technology with a nanosecond‐pulsed infrared laser
Authors: Zhang Mason , He Yaron , Huang Hanan
Published: November 2024

Traditional machining methods for glass drilling use contact‐based processes such as CNC, grinding wheels, or chemical etching, which easily cause surface microcracks, poor quality, or environmental pollution. Additionally, traditional glass sandblasting requires complex steps involving sandblasting and UV curing. Laser processing of glass instead is more efficient, environmentally friendly, and reliable.
Integration of sensors during laser powder bed fusion
Authors: Schönherr Andy , Voigt Sven , Schob Bernd , Bucksch Julia Ruiz , Kroll Lothar
Published: November 2024

Laser powder bed fusion (PBF‐LB/M) is an additive manufacturing (AM) process to produce high‐strength, functionally integrated, lightweight metal components which cannot be built conventionally. This article addresses the expansion of functionality by integrating sensors within closed cavities. For this reason, the building process was stopped just before the cavities were closed. After positioning the sensors, the building process was continued and a solid connection to the AM component was established.
Ultraviolet line structuring of large solar wafers
Authors: Schlutow Henrike , Fuchs Ulrike , Reinlein Claudia
Published: November 2024

Ultrashort‐pulsed lasers are ideal for material processing by welding, marking, and cutting. Scanning systems are crucial for large substrates. We introduce a novel UV line structuring method using deformable mirror technology and freeform optics. This approach aims to improve processing times on large substrates, especially for M12 solar wafer processing. By using a freeform lens and a Zwobbel deformable mirror, we achieve extended processing fields and high scan frequencies. The paper explores optical designs, their robust optomechanical implementation for prototyping, and setup characterization.
SiC high‐tech ceramics — a comparison of laser processes
Authors: Rochholz Christian , Meudtner Andreas
Published: November 2024

Extensive R&D applied various laser sources — from nanosecond VIS‐wavelength to femtosecond IR and water‐jet guided lasers — to enhance the quality and efficiency of laser structuring, fine cutting, and drilling of silicon carbide. Tests focused on surface roughness, cutting line precision, and high ablation rates. Challenges due to diverse material compositions, like diamond layers, required combined methods to develop viable approaches. To meet economic constraints, mechanical grinding was integrated with recurring laser processing.
Dielectric material processing with ultrashort pulses
Authors: Andriukaitis Deividas , Jašinskas Mantvydas , Gečys Paulius , Bischoff Christian
Published: November 2024

Femtosecond lasers have become essential tools in material processing. Thanks to their ultrashort pulse duration, these lasers can process a wide range of materials without causing significant thermal effects, leading to superior quality. Dielectric materials, especially glass and ceramics, are among those that benefit the most from femtosecond laser technology. Traditional processing methods often struggle with these materials, but femtosecond lasers provide a solution with high precision and quality.
The Rapid Decrease in the Biological Reactivity of Water Activated by Air Spark Discharge Plasma
Authors: Dou Di , Zhou Zhenyu , Chen Chao , Wang Qiang , Wang Zhishang , Liu Guoqiang , Feng Dongxue , Yang Jun , Wan Huihui , Zhang Tao , Liu Dongping
Published: November 2024

To investigate the biological reactivity of plasma‐activated water (PAW), we prepared PAW using atmospheric air spark discharge over water at 4°C and 25°C, with Escherichia Coli (E. coli) as the microbial model. The biological reactivity of PAW at 25°C decreased rapidly by 3.32 Logs within 20 s of storage. At 4°C, PAW showed high reactivity within 20–30 s of storage but decreased by 3.50 Logs between 30 and 60 s. Our analysis revealed that PAW reactivity is dependent on short‐lived peroxynitrite (ONOOH), formed through H2O2 and HNO2 under acidic conditions. ONOOH actively reacts with amino acid functional groups, as measured by high‐resolution LC‐MS, likely contributing to the rapid inactivation of E. coli.
Population pharmacokinetic modeling of zavegepant, a calcitonin gene‐related peptide receptor antagonist, in healthy adults and patients with migraine
Authors: Comisar Craig M. , Francis Jose , Hughes Jim H. , Bhardwaj Rajinder , Bertz Richard , Liu Jing
Published: November 2024

Zavegepant (ZAVZPRET™) is a high‐affinity, selective, small‐molecule calcitonin gene‐related peptide receptor antagonist available for acute treatment of migraine in adults. A population pharmacokinetic analysis was performed to describe zavegepant plasma concentration–time course, characterize bioavailability, and identify covariates affecting zavegepant exposure. The model was developed and validated using data from 10 phase I clinical studies, wherein zavegepant was administered intravenously, intranasally, or orally to healthy adults and patients with migraine. Plasma concentration–time data were analyzed using nonlinear mixed‐effects modeling. A three‐compartment model with first‐order elimination from the central compartment, and sequential zero‐ and first‐order absorption best described the observed plasma concentration–time course of zavegepant. Bioavailability was 5.1% and 0.65% for intranasal and oral treatment, respectively; absorption rate constants were 5.8 and 0.8 h−1, respectively. Body weight‐based empirical allometric scaling was applied using standard exponents (0.75 for clearance and 1 for volume of distribution). Age (range 18–71 years), race, ethnicity, sex, renal function, and co‐administration of oral contraceptives or sumatriptan did not significantly change zavegepant pharmacokinetics. Moderate hepatic impairment (Child‐Pugh score 7–9) or co‐administration of rifampin decreased elimination clearance of oral zavegepant by ~40%. The zavegepant population pharmacokinetic model adequately characterized zavegepant concentration–time profiles, the bioavailability of intranasal and oral zavegepant, as well as the effect of intrinsic and extrinsic factors on zavegepant pharmacokinetics.
Disulfide‐Rich Self‐Assembling Peptides Based on Aromatic Amino Acid
Authors: Huang Wenjing , Dong Huilei , Yan Qipeng , Deng Tingfen , Li Xiaoxu , Zhao Zhe , Li Zenghui , Wang Mingshui , Zhang Chunhui , Kong Bo , Shi Junfeng , Yuan Dan
Published: November 2024

Aromatic residues in assembling peptides play a crucial role in driving peptide self‐assembly through π–π stacking and hydrophobic interactions. Although various aromatic capping groups have been extensively studied, systematic investigations into the effects of single aromatic amino acids in assembling peptides remain limited. In this study, the influence of aromatic‐aromatic interactions on disulfide‐rich assembling peptides is systematically investigated by incorporating three different aromatic amino acids. Their folding propensity, self‐assembling properties, and rheological behaviors are evaluated. These results indicate that different aromatic‐aromatic interactions have a significant effect on self‐assembly abilities, as determined by critical aggregation concentration (CAC) measurements. Furthermore, the biocompatibility of these hydrogels is assessed, and their potential for 3D cell culture is explored. The injectable F1‐ox hydrogel demonstrate excellent biocompatibility for SHED and NIH3T3 cells and exhibit a porous structure that facilitates nutrient and cellular metabolic waste exchange. This work provides new insights into the molecular design of peptide‐based biomaterials, with a focus on the impact of aromatic residues on disulfide‐rich assembling peptides.
Biomimetic Superhydrophobic Surfaces by Nanoarchitectonics with Natural Sunflower Pollen
Authors: Li Jian , Deng Jingyu , Zhou Chenchen , Yang Jueying , Shin Sungmin , Binks Bernard P. , Cho Nam‐Joon
Published: November 2024

Superhydrophobic surfaces, known for their water‐repellent, and self‐cleaning properties, are widely used in various applications. These advanced functional surfaces exhibit high contact angles (>150°), achieved through low surface energy chemistries and hierarchical roughness. Natural sunflower pollen is micron‐sized spherical particles with nano‐sized spikes on the surface. This study engineered superhydrophobic coatings using the unique hierarchical structure of sunflower pollen and low surface energy additives like polydimethylsiloxane (PDMS) and silane additives such as 1H,1H,2H,2H‐perfluorooctyltrichlorosilane (FTS), octadecyltrichlorosilane (OTS) and dichlorodimethylsilane (DCDMS). The pollen content significantly modulates surface structure, roughness, and water contact angle. Higher pollen content enhances roughness and water repellency by creating micro‐nano hierarchical structures. Pollen‐PDMS‐FTS and Pollen‐PDMS coatings demonstrated the highest water contact angles (165 ± 2° and 163 ± 3°, respectively) and lowest sliding angles (4.5 ± 1° and 7.6 ± 2.6°, respectively), achieving a “lotus effect.” Conversely, Pollen‐PDMS‐OTS or Pollen‐PDMS‐DCDMS coatings resulted in high sliding angles and water adhesion, producing a “rose petal effect.” These “lotus effect” coatings are effectively applied in self‐cleaning and water displacement in oil pipelines on hilly terrain. This study provides insights into the interplay between hierarchical structure and surface‐free energy for designing superhydrophobic surfaces tailored for specific applications.
Unveiling Relationships: Enhancing Sustainability of Golpata (Nipa Palm) Through Socio‐Ecological Systems Management in the Sundarbans Mangrove Forest
Authors: Ahasan S. M. Nayem , Ashik Ur Rahman Md
Published: November 2024

This study explores the social‐ecological dynamics of common pool resource (CPR) management in the Sundarbans mangrove forest in Bangladesh. We focus on golpata (Nypa fruticans), a vital CPR for local communities. A social‐ecological systems (SESs) framework was employed to assess the relationships between social (actors and governance) and ecological (resource system and resource unit) dimensions and their influence on the sustainability of golpata management. Data on 12 variables and 24 indicators were collected within the Chadpai range of the Sundarbans. Results revealed both positive and negative relationships between the SES dimensions. Positive correlations were found between the resource system and resource unit, and between governance and both resource system and unit (albeit weaker). Conversely, negative correlations emerged between actors and both resource systems and units, suggesting a potential disconnect between community user practices and resource sustainability. Based on these findings, the study recommends four distinct management scenarios tailored to specific SES regions within the Sundarbans. These scenarios emphasize strengthening governance frameworks, enhancing stakeholder engagement, and implementing targeted ecological interventions to improve the sustainability of golpata resources. This research contributes to a deeper understanding of the social‐ecological complexities of golpata management in the Sundarbans. The findings can inform policymakers in developing effective strategies for sustainable resource use and community livelihoods within this critical ecosystem.
Virulence and Antimicrobial Resistance Patterns of Salmonella spp. Recovered From Migratory and Captive Wild Birds
Authors: Begum Ruhena , Asha Nilima Akther , Dipu Diponkar Chandra Chanda , Roy Milton , Rahman Asikur , Chowdhury Md. Shahidur Rahman , Hossain Hemayet , Islam Md. Rafiqul , Uddin Md Bashir , Rahman Md. Mahfujur , Hossain Md. Mukter
Published: November 2024

Background

Salmonella spp., especially those are resistant to extended‐spectrum β‐lactamase (ESBL), are considered as major concern to global health due to their emergence and dissemination.

Aim

The aim of this study was to investigate the virulence and antimicrobial resistance (AMR) profile of Salmonella spp. from migratory and captive wild birds.

Method

A total 262 faecal samples were collected, and the identification of Salmonella spp. was carried out using a standard culture and PCR as well as molecular detection of virulence and AMR genes.

Results

The overall prevalence of Salmonella was determined to be 30.92% (95% CI = 25.63–36.75). Migratory birds exhibited highest prevalence (38.10%), whereas wild birds in captivity showed a lower prevalence (23.40%). The agfA gene was detected at a higher rate at 24.69%. Salmonella spp. exhibited 100% resistance to tetracycline, followed by 58% ampicillin and 46% streptomycin. In addition, there was a resistance rate to ceftriaxone of 17% and to colistin sulphate of 25%. Interestingly, levofloxacin alone displayed 100% sensitivity across all isolates, while ciprofloxacin and azithromycin showed 73% and 64% sensitivity, respectively. The MAR index was 0.25 and 0.42, and 74.07% of all isolates showed multidrug resistance (MDR). It was shown that migratory and captive wild birds contained ESBL genes blaTEM (94.34% and 49.06%) and blaSHV (13.33% and 10%), respectively. Genes responsible for sulphonamide (sul1) resistance were detected in 13.33% and 79% of wild and migratory birds, respectively.

Conclusion

Salmonella has been found in captive wild and migratory birds and could act as reservoirs for the transmission of MDR and ESBL bacteria.
Urbanisation increases cloudiness over Greater Kuala Lumpur during southwest and northeast monsoons
Authors: Syed Mahbar Sharifah Faridah , Kusaka Hiroyuki
Published: November 2024

Understanding urban cloud dynamics is vital, as changes in local cloud patterns impact energy and water cycles, posing risks to cities. This study examined urban cloudiness using Himawari‐8 satellite data from 2016 to 2021 during the southwest and northeast monsoons in Greater Kuala Lumpur. Urban areas exhibited higher daytime cloud cover than rural areas, with peak cloudiness at 1500 local time being 1.22 times greater during southwest monsoon and 1.24 times greater during the northeast monsoon. Increased solar radiation and the urban heat island effect drive these variations, offering insights for weather forecasting and climate studies in rapidly urbanising regions.
Imagining a New Gender Contract for SRHR
Authors: Dzwonkowska-Godula Krystyna
Published: November 2024

This chapter focuses on the importance of sexual and reproductive health and rights (SRHR) for gender equality. SRHR studies are crucial for human beings’ health and well-being, individual dignity and autonomy, and in the context of human and women’s rights. In our considerations, we explore selected aspects of SRHR, such as sex education, and access to modern contraception and abortion, all conditioning people’s reproductive choices and, thus, life choices and chances. The following issues are discussed in the chapter: the differences within the EU in realising SRHR with respect to the above-mentioned aspects; and the significance of including reproductive justice in building a new gender contract and an inclusive Europe. In the final section, we identify selected courses of action and solutions that can contribute to this goal. Adopting the perspective of reproductive justice, which combines reproductive rights with social justice and the intersectionality approach, is useful in the critical analysis of reproductive politics in European countries and formulating recommendations to create a new gender contract as a basis for a more inclusive, fairer and feminist Europe. However, it also includes intra- and transnational cooperation in supporting women’s access to abortion and contraception.
Conformal bootstrap equations from the embedding space operator product expansion
Authors: Fortin Jean-François , Ma Wen-Jie , Prilepina Valentina , Skiba Witold
Published: November 2024

Abstract

We describe how to implement the conformal bootstrap program in the context of the embedding space OPE formalism introduced in previous work. To take maximal advantage of the known properties of the scalar conformal blocks for symmetric-traceless exchange, we construct tensorial generalizations of the three-point and four-point scalar conformal blocks that have many nice properties. Further, we present a special basis of tensor structures for three-point correlation functions endowed with the remarkable simplifying property that it does not mix under permutations of the external quasi-primary operators. We find that in this approach, we can write the M-point conformal bootstrap equations explicitly in terms of the standard position space cross-ratios without the need to project back to position space, thus effectively deriving all conformal bootstrap equations directly from the embedding space. Finally, we lay out an algorithm for generating the conformal bootstrap equations in this formalism. Collectively, the tensorial generalizations, the new basis of tensor structures, as well as the procedure for deriving the conformal bootstrap equations lead to four-point bootstrap equations for quasi-primary operators in arbitrary Lorentz representations expressed as linear combinations of the standard scalar conformal blocks for spin-ℓ exchange, with finite ℓ-independent terms. Moreover, the OPE coefficients in these equations conveniently feature trivial symmetry properties. The only inputs necessary are the relevant projection operators and tensor structures, which are all fixed by group theory. To illustrate the procedure, we present one nontrivial example involving scalars S and vectors V, namely ⟨SSSV⟩.
Celestial Lw1+∞ charges from a twistor action
Authors: Kmec Adam , Mason Lionel , Ruzziconi Romain , Srikant Akshay Yelleshpur
Published: November 2024

Abstract

The celestial Lw1+∞ symmetries in asymptotically flat spacetimes have a natural geometric interpretation on twistor space in terms of Poisson diffeomorphisms. Using this framework, we provide a first-principle derivation of the canonical generators associated with these symmetries starting from the Poisson BF twistor action for self-dual gravity. We express these charges as surface integrals over the celestial sphere in terms of spacetime data at null infinity. The connection between twistor space and spacetime expressions at $$ \mathcal{I} $$
I
is achieved via an integral formula for the asymptotic Bianchi identities due to Bramson and Tod. Finally, we clarify how Lw1+∞ transformations are symmetries of gravity from a phase space perspective by showing the invariance of the asymptotic Bianchi identities.
Laser power modulation between disturbed and undisturbed material removal regime in laser chemical processing
Authors: Lu Yang , Bouraoui Yasmine , Niehaves Claudia , Fischer Andreas , Radel Tim
Published: November 2024

Laser chemical machining (LCM) is a method for removing material by thermally induced chemical dissolution of self-passivating metals. However, the process window is limited by disrupted material removal due to gas bubble formation and metallic salts and oxides deposition at higher energy input. Since the temperature increases, and therefore gas bubble growth takes time, it is hypothesized that the temporal modulation of laser power can remove the metal homogeneously, i.e., without disrupted material removal, while achieving a higher removal rate. Based on this, the dynamic process behavior of material removal is investigated for the LCM of titanium in phosphoric acid, using a rectangular modulation of the laser power with varying irradiation durations. As a result, however, high-speed videos show that gas bubbles are consistently generated, regardless of the applied laser power and power modulation, although the quantity of bubbles varies with different parameters. Even with short power durations (10 ms), the material deposition occurs after multiple irradiations. When the duration is longer, the material deposition increases in height along the laser scan direction. For the studied process parameters, a Fourier analysis in the spatial domain further indicates the correlation between the material removal frequencies and the modulation frequencies. In conclusion, the laser power modulation cannot prevent the disturbed material removal at high laser powers. Nevertheless, the material deposition can be utilized to generate periodic surface structures with a depth below and above the initial surface.
A data-driven approach for analyzing contributions of individual loading factors to GNSS-measured bridge displacements
Authors: Qu Xuanyu , Ding Xiaoli , Xia Yong , Yu Wenkun
Published: November 2024

A bridge may displace due to various loadings (e.g., thermal (Xia et al. in Struct Control Health Monit 28(7):e2738, 2013), winds (Owen et al. in J Wind Eng Ind Aerodyn 206:104389, 2020), and vehicles (Xu et al. in J Struct Eng 133(1):3–11, 2007)) acting upon the bridge. Identifying the contributions of individual loading factors to the measured bridge displacements is important for understanding the structural health conditions of the bridge. There is however no effective method to quantify the contributions when multiple loadings act simultaneously on a bridge. We propose a new data-driven method, termed random forest (RF)-assisted variational mode decomposition (RF-AVMD), for more effective identification of dominant loading factors and for quantifying the contributions of individual loading factors to the measured bridge displacements. The proposed method is applicable to studying the displacements of any bridge structures and allows for the first time to separate the contributions of individual loadings. The effectiveness of the proposed method is validated using data from Tsing Ma Bridge (TMB), a large suspension bridge in Hong Kong recorded during two consecutive strong typhoons. The results reveal that the transverse displacements of TMB mid-span were controlled by the crosswinds, the longitudinal displacements were dominated by the temperature and winds along the bridge centerline, and the vertical displacements were mainly due to the winds along the bridge centerline, temperature, and traffic flows. Displacement time series that responded to each loading factor was derived. The proposed method provides important new insights into the impacts of individual loadings on the displacements of long-span bridges.
Vulnerability of kelp, Ecklonia radiata, to persistent nitrogen pollution and coastal darkening
Authors: Mason Josie M. , Blain Caitlin O.
Published: November 2024

Coastal darkening is expected to have pervasive impacts on benthic primary producers. However, the effects of nitrogen enrichment, an often-co-occurring stressor, on benthic primary producers and their functions is less clear. This study investigates the interactive effects of coastal darkening and nitrogenous eutrophication, including nitrogen source (NH4+ vs. NO3−), on the function of the kelp Ecklonia radiata. First, an in-situ experiment was used to assess the differential impacts of NH4+ and NO3− pulse enrichment on the photosynthetic performance and pH modulation capacity of E. radiata. Second, a laboratory experiment was used to assess the longer-term impacts of nitrogen enrichment under low-light conditions mimicking coastal darkening on service provisioning, including photosynthetic performance, pH modulation, nutrient uptake and growth. While pulse nitrogen enrichment had no impacts on the photosynthetic performance of E. radiata in-situ, persistent exposure to either NH4+ or NO3− acted as a stressor to sporophytes as indicated by elevated rates of dark respiration and lamina erosion and reduced photosynthetic efficiency and growth rates. Furthermore, low-light conditions elicited reduced photosynthetic capacity at saturating irradiance, which extended to a reduction in the extent of pH modulation, and significantly increased lamina erosion. While the two stressors appeared to act on distinct parameters, ultimately, both darkening and eutrophication directly reduced net primary production, especially when in combination. These results demonstrate the negative interactive effects of coastal darkening and eutrophication on E. radiata function, while suggesting a vulnerability of E. radiata to even moderate levels of persistent nitrogen enrichment. This vulnerability highlights the need to consider environmental conditions during kelp conservation and restoration, and when attempting to valorise kelp ecophysiology for nature-based solutions.
Altruistic giving and risk taking in human affairs
Authors: Stark Oded , Balbus Lukasz
Published: November 2024

The purpose of this paper is to provide a general proposition of the relationship between altruism and risk taking. As explained in the body of the paper, we diverge from a result reported in Stark et al. (2022) and provide an expansion and a generalization of a preliminary result reported in Stark (2024). In a broad utility framework, we study the risk aversion of an altruistic person who is an active donor (benefactor) and the risk aversion of a beneficiary of an altruistic transfer. In both cases, we find that altruism lowers risk aversion. The specific case in which the utility functions of the benefactor and of the beneficiary are constant relative risk aversion (CRRA) functions constitutes a vivid example of lesser risk aversion characterization. We conclude that in terms of risk-taking behavior, a “population” endowed with altruism is uniformly more willing to take risks than a comparable “population” devoid of altruism.
Improving subseasonal forecast skill in the Norwegian Climate Prediction Model using soil moisture data assimilation
Authors: Nair Akhilesh S. , Counillon François , Keenlyside Noel
Published: November 2024

This study shows the importance of soil moisture (SM) in subseasonal-to-seasonal (S2S) predictions at mid-latitudes. We do this through introducing the Norwegian Climate Prediction Model Land (NorCPM-Land), a land reanalysis framework tailored for integration with the Norwegian Climate Prediction Model (NorCPM). NorCPM-Land assimilates blended SM data from the European Space Agency’s Climate Change Initiative into a 30-member offline simulation of the Community Land Model with fluxes from the coupled model. The assimilation of SM data reduces error in SM by 10.5 % when validated against independent SM observations. It also improves latent heat flux estimates, illustrating that the adjustment of underlying SM significantly augments the capacity to model land surface dynamics. We evaluate the added value of land initialisation for subseasonal predictions, by comparing the performance of hindcasts (retrospective prediction) using the standard NorCPM with a version where the land initial condition is taken from NorCPM-Land reanalysis. The hindcast covers the period 2000 to 2019 with four start dates per year. Land initialisation enhances SM predictions, reducing error by up to 2.5-month lead time. Likewise, the error for precipitation and temperature shows improvement up to a lead time of 1.5-month. The largest improvements are observed in regions with significant land-atmospheric coupling, such as the Central United States, the Sahel, and Central India. This method further enhances the prediction of extreme temperature variations, both high and low, with the most notable improvements seen in regions at mid and high latitudes, including parts of Europe, the United States, and Asia. Overall, our study provides further evidence for the significant role of SM content in enhancing the accuracy of subseasonal predictions. This study introduces a technique for improved land initialisation, utilising the same model employed in climate predictions.
Birthing positions and mother`s satisfaction with childbirth: a cross-sectional study on the relevance of self determination
Authors: Scholten Nadine , Strizek Brigitte , Okumu Mi-Ran , Demirer Ibrahim , Kössendrup Jan , Haid-Schmallenberg Lissa , Bäckmann Malte , Stöcker Arno , Stevens Natalie , Volkert Anna
Published: November 2024

Introduction

Considering the inconclusive evidence regarding the clinical benefits of specific birthing positions, emphasis has been placed on adhering to women’s preferences during the second stage of labour. Therefore, the present study aimed to assess the association between birthing position, the freedom to choose a birth position during the second stage of labour, and women’s subjective satisfaction with childbirth.

Methods

We performed a cross-sectional survey of women 8 or 12 months after a vaginal birth in a hospital. The women were recruited via two cooperating health insurance companies. Multivariate analyses were conducted to assess the strength of the association between birthing position and maternal satisfaction with childbirth, with a particular focus on interactions with self-determination.

Results

In total, the data from 761 women were analysed. The supine position was the most frequently reported birthing position in the second stage of labour at 77.5%. Notably, 39.0% and 30.5% of the women who gave birth in the dorsal and lateral supine positions, respectively, stated that the birth position was not chosen voluntarily. The regression models show a significant negative association between supine birthing position and satisfaction with childbirth, which is significantly related to self-determination. The most common reason for the adoption of a specific birthing position was instructions from medical staff.

Discussion

The data provide insight into the perceived satisfaction with childbirth depending on the birthing position, whereby the relevance of self-determination is particularly evident. At the same time, self-determination is often not given, which is associated with reduced birth satisfaction.
XNLP-Completeness for Parameterized Problems on Graphs with a Linear Structure
Authors: Bodlaender Hans L. , Groenland Carla , Jacob Hugo , Jaffke Lars , Lima Paloma T.
Published: November 2024

In this paper, we showcase the class XNLP as a natural place for many hard problems parameterized by linear width measures. This strengthens existing W[1]-hardness proofs for these problems, since XNLP-hardness implies W[t]-hardness for all t. It also indicates, via a conjecture by Pilipczuk and Wrochna (ACM Trans Comput Theory 9:1–36, 2018), that any XP algorithm for such problems is likely to require XP space. In particular, we show XNLP-completeness for natural problems parameterized by pathwidth, linear clique-width, and linear mim-width. The problems we consider are Independent Set, Dominating Set, Odd Cycle Transversal, (
q
-)Coloring, Max Cut, Maximum Regular Induced Subgraph, Feedback Vertex Set, Capacitated (Red-Blue) Dominating Set, Capacitated Vertex Cover and Bipartite Bandwidth.
A meningoencephalitis outbreak associated with echovirus type 18 (E18) in south-western Hungary in mid-2023
Authors: Takáts Károly , Balázs Benigna , Boros Ákos , Sipos Dávid , Péterfi Zoltán , Harmat Márk , Varga Dávid , Zengő-Bedő Zita , Pankovics Péter , Reuter Gábor
Published: November 2024

Echovirus type 18 (E18) is a member of the genus Enterovirus of the family Picornaviridae. In this study, we investigated the characteristics of E18 infections in hospitalized adults with meningoencephalitis that occurred during an unusual epidemic in south-western Hungary in mid-2023. Five (6.1%) out of 82 cerebrospinal fluid specimens that were tested were positive for an enterovirus, four of which were E18 (OR372160 and PP861087-PP861090). Headache (100%), fever (75%), retrobulbar pain (50%), nausea (50%), joint/limb pain (50%), exanthema, photophobia, and vomiting were the most common symptoms. Sequence analysis showed that these viruses were related to unpublished emerging E18 strains from France (2022/2023) and China (2019/2020). Further study is necessary to monitor the circulation of epidemic/pandemic E18 variants over time.
Training transfer validity of virtual reality simulator assessment
Authors: Hjellvik Simen , Mallam Steven
Published: November 2024

This study utilises computer-based simulations to explore the transfer effects of competency training in maritime education, addressing the current lack of research on their transferability to real-world scenarios.

The research explores the accuracy of procedural knowledge assessment using virtual reality (VR), positing that head-mounted display (HMD) VR offers stronger concurrent validity through training transfer measures than 3D desktop VR. This is evaluated by regression on a training transfer condition. It also investigates motivation’s influence on training transfer and the regression model of this relationship.

Fifteen marine engineering students were divided into two experimental groups using 3D desktop VR and HMD VR systems, with eight experts in the control group. The students had previously received traditional lecture-based instruction and were given practical training using a 2D desktop simulator in the same scenario as in the VR treatment and in the training transfer condition.

The ANCOVA design experiment involved two levels of technical immersion before the operation of real-life equipment. Neither technical immersion nor expertise level as independent variables were found to have a significant effect in the relationship of the assessment predicting the training transfer. The direct relationship was significant (R2adj = 0.436) and further analysed with the influence of motivation, resulting in a moderation model with a decent effect size (R2 = 0.740). Based on these findings, we can infer that both types of VR simulations used for assessment demonstrate concurrent validity in predicting real-life performance before we discuss and define the characteristics of the observed transfer according to theory.
The impact of SARS-CoV-2 (COVID-19) pandemic on educational and professional growth of young Italian epileptologists: a survey of the Young Epilepsy Section-Italian chapter
Authors: Masnada Silvia , Spagnoli Carlotta , Duca Maddalena , Chiarello Daniela , Lo Barco Tommaso , Nucera Bruna ,   On Behalf of Young Epilepsy Section—Italian chapter, Balestrini Simona , De Palma Luca , Battaglia Giulia , Ferri Lorenzo , Dono Fedele
Published: November 2024

Objectives

In March 2020, the World Health Organization declared the coronavirus-related disease SARS-CoV-2 infection pandemic. Italy was one of the most affected countries and managed the emergency also by a health care reorganization.

Methods

The Education and Career Development Task Force of the Young Epilepsy Section-Italy (YES-I) designed a survey to assess the impact of the pandemic on the training and work of young epileptologists (< 40 years).

Results

Fifty-three responses were collected: 45.3% were resident, 9.4% PhD students and the remainder specialists. Clinical activity changed for most (83%) during the pandemic. Educational activity at epilepsy centers was reduced for 35.8% of the survey participants, while 30.2% of research projects involving patients participation were stopped to switch mainly to COVID-19-related research. For 73.6% of survey participants, attending online courses and congresses was easier in terms of cost and organization, although for 50.9% the level of training was lower in quality. In contrast, 58.5% rated the webinars organized by YES-I very educational. Less than 50% of the clinicians used telemedicine in the pandemic period and continue to use it. Despite several positive aspects of virtual medicine, a small number (32.1%) of our interviewees were satisfied from telemedicine and few of them (30.2%) reported that it led to improvement of clinical practice.

Conclusions

Our survey showed that the pandemic has had a negative impact on training, research and clinical activity in the epilepsy field; moreover, it underlined the critical aspects of virtual communication methods in order to improve its use for the future.