bluuebunny/crossref_metadata_2025 huggingface dataset:
A probabilistic fatigue life assessment method for wind turbine blade based on Bayesian GPR with the effects of pitch angle
Authors: Zhang Xiaoling , Zhang Kejia , Chen Zhongzhe
Published: May 2024

The fatigue behavior of large wind turbine blades is complex and stochastic due to their complex structure and operating environment. This paper focuses on developing a probabilistic fatigue life assessment method for wind turbine blades considering the uncertainties from wind velocity, material mechanical properties, pitch angle, and layer thickness. To improve the efficiency of stochastic fatigue behavior analysis of wind turbine blade, unidirectional fluid‐structure coupling (UFSC) and bidirectional fluid‐structure coupling (BFSC) analysis are employed to analyze the stochastic response. Then, Gaussian process regression (GPR) and Bayesian updating are combined to establish the stochastic fatigue behavior prediction model for wind turbine blade. On this basis, a modified S‐N curve formulation is proposed, and the fatigue life of wind turbine blade is analyzed by the modified S‐N curve and compared with the three‐parameter Weibull model. The results indicate that the proposed method for fatigue life assessment has better accuracy. The proposed probabilistic fatigue life assessment method with high accuracy and high efficiency, which is beneficial for the fatigue reliability design of wind turbine blades.
Adaptive neural network‐based practical fixed‐time consensus tracking for second‐order nonlinear multi‐agent systems with switching topologies
Authors: Dong Yan , Lu Weihua , Chen Junwei , Cao Jinde , Xu Shunlin
Published: May 2024

The current study concerns the practical fixed‐time consensus tracking problem of second‐order nonlinear multi‐agent systems (MASs) with switching topologies. The neural network (NN) and adaptive technique are adopted to compensate the unknown nonlinearities of the followers. Then, an adaptive NN‐based fixed‐time controller is designed under switching interaction topologies. In order to give the rigorous proof of the practical fixed‐time consensus tracking, a novel lemma for analyzing the practical fixed‐time stability of the switched error system is firstly established, then by constructing appropriate topology‐dependent multiple Lyapunov functions, we theoretically show that the practical fixed‐time consensus tracking of the closed‐loop MASs can be ensured provided that the dwell time of the switching topologies is larger than a predefined threshold and further the involved control parameters are suitably selected. Moreover, the settling time estimation is explicitly given, which is regardless of the system's initial values. The theoretical results are finally verified via a numerical simulation.
Microwave Properties of Composite Films Based on Polyvinyl Chloride and Brominated Activated Carbon
Authors: Grishchenko Liudmyla M. , Zhytnyk Dmytro O. , Matushko Igor P. , Diyuk Vitaliy E. , Noskov Yuriy V. , Malyshev Volodymyr Yu. , Moiseienko Vladyslav A. , Boldyrieva Olga Yu. , Lisnyak Vladyslav V.
Published: May 2024

Brominated activated carbon (AC/Br2) powder was used as a filler in poly(vinyl chloride) (PVC) to prepare PVC‐based composite films by hot pressing. The AC/Br2 filler was obtained by liquid phase bromination and contained both oxygen and bromine. In comparison with the unmodified AC, the AC/Br2 was subjected to thermogravimetric analysis in air and argon and temperature‐programmed desorption mass spectrometry in vacuum, which identified carbon‐oxygen and bromine groups and showed the comparable thermal stability of AC/Br2 and AC. XPS shows the predominance of phenolic groups among the carbon‐oxygen groups. Scanning electron microscopy and transmission electron microscopy showed preserved morphology and microstructure, while N2 adsorption showed a microporosity decrease after bromination. FTIR analysis suggested non‐chemical interactions between PVC and AC/Br2. As the AC/Br2 content in the PVC‐based composite films increases from 0.2 to 30 wt %, the electromagnetic radiation (EMR) reflection at Ka‐band microwave frequencies increases. To reduce the EMR reflection, the proposed composite films should contain a maximum of 0.2 wt % AC/Br2. The results indicate that the microwave properties of PVC‐based composite films can be tuned by adjusting the AC/Br2 content.
Green Chemistry Approach for One‐Step Synthesis of Iodinated Graphene Material for Supercapacitor Applications
Authors: Kalicharan Alvin , Pitchaimani Jayaraman , Barath Kanna C. , Rajesh Vudata , Tamtam Mohan Rao , Koutavarapu Ravindranadh , Baby Shakila P. , Ramesh Pugalenthi
Published: May 2024

Iodinated graphene is a promising 2D material with unique physical and chemical characteristics. A new synthesis method that combines iodine intercalation and surface reduction of graphite sheets in a single step was developed. This method uses NaIO4 and m‐CPBA to efficiently incorporate iodine and selectively remove oxygen from the graphene network at room temperature. The presence of iodine moieties in the graphene network was confirmed using various techniques such as XPS photoelectron spectroscopy, HR‐TEM, XRD, FT‐IR, TGA, and Raman spectroscopy. The high iodine content of the material enhanced the d‐spacing and ion mobility of the electrolyte, thereby improving the storage capacity. In addition, the potential of iodinated graphene as an electrode material was investigated through EIS, CV, and GCD using 1 M H2SO4 solution as the electrolyte. The iodinated graphene material exhibited EDL capacitance and demonstrated an impressive specific capacitance of 535.4 F g−1 at a high rate, with a current density of 1 A g−1. Moreover, it exhibited exceptional stability over 5000 cycles. These halogenated graphene derivatives are attractive options for use in supercapacitors.
Controllable Design of Metal‐Organic Framework‐Derived Vanadium Oxynitride for High‐Capacity and Long‐Cycle Aqueous Zn‐Ion Batteries
Authors: Liu Yuexin , Zhang Jing , Liu Yuan , Zhang Mingcheng , Pan Zhenghui , Cai Kefeng
Published: May 2024

Introducing N atoms in vanadium oxides (VOx) of aqueous Zn‐ion batteries (ZIBs) can reduce their bandgap energy and enhance their electronic conductivity, thereby promoting the diffusion of Zn2+. The close‐packed vanadium oxynitride (VON) generated often necessitates the intercalation of water molecules for restructuring, rendering it more conducive for zinc ion intercalation. However, its dense structure often causes structural strain and the formation of by‐products during this process, resulting in decreased electrochemical performance. Herein, carbon‐coated porous V2O3/VN nanosheets (p‐VON@C) are constructed by annealing vanadium metal‐organic framework in an ammonia‐contained environment. The designed p‐VON@C nanosheets are efficiently converted to low‐crystalline hydrated N‐doped VOx during subsequent activation while maintaining structural stability. This is because the V2O3/VN heterojunction and abundant oxygen vacancies in p‐VON@C alleviate the structural strain during water molecule intercalation, and accelerate the intercalation rate. Carbon coating is beneficial to prevent p‐VON@C from sliding or falling off during the activation and cycling process. Profiting from these advantages, the activated p‐VON@C cathode delivers a high specific capacity of 518 mAh g−1 at 0.2 A g−1 and maintains a capacity retention rate of 80.9% after 2000 cycles at 10 A g−1. This work provides a pathway to designing high‐quality aqueous ZIB cathodes.
Magnetic soft centirobot to mitigate biological threats
Authors: Vaghasiya Jayraj V. , Mayorga‐Martinez Carmen C. , Zelenka Jaroslav , Sharma Shelja , Ruml Tomas , Pumera Martin
Published: May 2024

Soft robots have drawn a lot of interest in the field of human–robot interfaces because they can mimic the propulsion of soft bodies and archive complex tasks that cannot be made by rigid robots such as performing the complex motion, avoiding collisions by absorbing impacts, and shape adaptation by elastic deformation. Herein, drawing inspiration from creatures in the Cambrian period, such as Hallucigenia, we develop a centimeter‐sized soft robot with multiple magnetic legs (referred to as a soft centirobot). This robot is equipped with graphitic carbon nitride (g‐C3N4) nanosheets to kill biological threats by photogenerated reactive oxygen species under black light illumination. The motion of g‐C3N4 soft centirobot is controlled by magnetic actuation even in complex wastewater samples (with a relative speed of 0.12 body lengths per second). The magnetic multilegs work as a propeller to walk across and cover large regions, and water disinfection is more efficient than what could be achieved by nano/micrometer scale sheets of g‐C3N4. Finally, factors affecting the accelerated propulsion of g‐C3N4 soft centirobot such as design principle, structure geometry, body mass, driving mechanism, and magnetic sensitivity, have been investigated. We envision that such a photoactive 2D material‐based integrated centimeter‐sized robot shall find application in many areas where pathogen removal is required.
Nanogold Foundry Involving High‐Shear‐Mediated Photocontact Electrification in Water
Authors: Alotaibi Badriah M. , Gardner Zoe , Vimalanathan Kasturi , Chen Xianjue , Alharbi Thaar M. D. , Raston Colin L.
Published: May 2024

Controlling the size and morphology of gold nanoparticles occurs in the absence of added reducing agents or other excipients such as surfactants, on UV irradiation (λ 254 nm) of aqueous auric acid (H[AuCl4]) in a thin film of liquid in a vortex fluidic device (VFD) within a rapidly rotating tilted quartz tube. This involves contact electrification (CE), which occurs at the solid−liquid interface with the oxidation of water photoinduced, forming the hydroxyl radical, OH•. In air, the redox couple is reduction of 3O2 to the superoxide radical anion, O2−•, which then reduces Au3+ to elemental gold, as does other reactive oxygen species present, competing with CE reduction of Au3+. The resulting nanogold structures effectively mold the different high‐shear topological fluid flows in the VFD, being isolated as ultrathin 2D sheets, prisms, hierarchical structures comprising nanoparticles embedded within these sheets, and rosette and tubular structures, depending on the VFD processing parameters and the concentration of auric acid. Processing under a nitrogen atmosphere while UV irradiated affords mainly 2D gold through the above reduction of Au3+. The findings establish a paradigm for VFD processing in water involving photo‐CE, generating hydrogen peroxide and hydrogen gas with the surfaces of the gold nanoparticles pristine.
Starch and Shellac Polymer Blends: A Promising Material for Extending Postharvest Fruit Shelf Life
Authors: Krongrawa Wantanwa , Piyawatakarn Piyapoom , Piriyaprasarth Suchada , Patomchaiviwat Vipaluk , Sriamornsak Pornsak , Chansatidkosol Siraprapa , Limmatvapirat Chutima , Limmatvapirat Sontaya
Published: May 2024

This study optimizes edible coatings made from starch and shellac (SHL) polymer blends to enhance postharvest preservation of fruits. Various starch:SHL ratios are explored for the following four different starch sources: rice (RIC), corn (COR), glutinous rice (GLU), and tapioca (TAP). The resulting polymer blend films are comprehensively analyzed via X‐ray diffraction, Fourier‐transform infrared spectroscopy, contact angle measurements, and studies of swelling behavior, water solubility, water vapor permeability, and mechanical properties. Phase separation is noted in the RIC:SHL and COR:SHL polymer blend films, while the TAP:SHL and GLU:SHL polymer blend films exhibit homogeneity without discernible interactions between starch and SHL. However, the TAP:SHL blend films exhibit superior mechanical properties compared with the GLU:SHL polymer blend films. Furthermore, the wettability, swelling, and water vapor permeability decrease upon increasing the SHL content in the polymer blend films. Noteworthily, the TAP:SHL polymer blend demonstrates favorable properties for use in fruit coatings. In contrast to the 100% SHL film, the TAP:SHL coatings do not exacerbate anaerobic respiration‐related browning during storage assessment. The findings highlight TAP:SHL polymer blend as a promising renewable material for extending fruit shelf life postharvest.
Gaze of Kampo specialists during simulated dynamic abdominal examinations: A cross‐sectional study using a wearable eye tracker
Authors: Yamada Rie , Xu Kuangzhe , Fujimoto Makoto , Kido Toshiki
Published: May 2024

Aim

We aimed to clarify the characteristics of the Kampo specialists' gaze during Kampo abdominal examinations on simulated patients and obtain suggestions for improving medical students' gaze during Kampo medicine abdominal examinations.

Methods

We recorded and quantitatively evaluated the gazes of eight Kampo specialists and six medical students using a wearable eye tracker during abdominal examinations of simulated patients.

Results

When specific sites were observed during abdominal examinations, the Kampo specialists' gaze toward the simulated patient's face was significantly higher than that of the medical students (mean = 1.019, 95% highest density interval: 0.159–2.050). A significant difference was also observed between the two populations regarding the specific sites observed. The medical students' gaze durations toward the simulated patient's eyes (mean = −2.696; 95% highest density interval: −4.961 to −0.744), face (mean = −1.881; 95% highest density interval: −3.353 to −0.691), upper limbs (mean = −1.707; 95% highest density interval: −2.932 to −0.500), and lower limbs (mean = −2.555; 95% highest density interval: −4.730 to −0.654) were significantly longer than those of Kampo specialists.

Conclusions

The medical students' gazes were dispersed; those of Kampo specialists were focused and of short durations. These findings suggest that Kampo specialists quickly collect essential diagnostic information and look away from the patient's face to concentrate on considering the Kampo medicine diagnosis. Teaching Kampo specialists' gaze techniques in Kampo medicine education could lead to improvements in the gaze of medical students during abdominal examinations.
A rapid monitoring protocol to estimate unharvested corn biomass in waterfowl impoundments
Authors: Highway Cory J. , Masto Nicholas M. , Blake‐Bradshaw Abigail G. , Keever Allison C. , Feddersen Jamie C. , Hagy Heath M. , Combs Daniel L. , Cohen Bradley S.
Published: May 2024

Conservation planners use bioenergetic models to develop habitat objectives that satisfy energetic demands of waterfowl during nonbreeding periods. In turn, natural resource managers should estimate yield and availability of natural and cultivated waterfowl forage to monitor contributions to objectives and support adaptive resource management. Because bioenergetic models are particularly sensitive to unharvested flooded croplands, we developed a rapid methodology to estimate biomass of unharvested flooded corn (Zea mays) and tested our methodology in impounded corn fields planted and flooded in western Tennessee during autumn and winter of 2019–2021. We evaluated accuracy of our rapid assessment method and conducted simulations to assess variance‐bias trade‐offs relative to sample size. Rapid assessments lasted 20 min ± 10 minutes per field. Our rapid assessment method underestimated number of kernels per ear by 2.6% ± 0.5%. After adjusting for underestimation bias, corn biomass across all surveys was 5,500 kg/ha ± 250 kg/ha, which is similar yield to previous literature from waterfowl impoundment fields. Sampling 15 ears per field allowed field biomass to be estimated within acceptable accuracy (i.e., variance [SE] of mean percent error <1.8%). We recommend our rapid yield assessment method be incorporated into habitat monitoring protocols to efficiently and precisely estimate corn biomass for improved conservation planning initiatives. Additionally, our rapid assessment method allows managers to monitor field yield rapidly, enabling estimates of corn depletion and availability throughout the nonbreeding season for waterfowl to support management decisions.
Complexes of Alkali Metal and the Ammonium Ion with the Cyclodimethylsiloxane Ligands D7 and D8 (D=Me2SiO)
Authors: Richter Roman‐Malte , von Hänisch Carsten
Published: May 2024

We present complexes of alkali metal ions and the ammonium ion with the large cyclodimethylsiloxanes D7 and D8 (D=Me2SiO). The formation of such complexes is accompanied by rearrangements of the ligands to form complexes with a suitable ring size for the metal used. These rearrangements could be suppressed by suitable reaction conditions and rapid work‐up of the reaction mixtures. This enabled the isolation of [Li(D7)][GaI4] (1), [Li(D8)][GaI4] (2), [Na(D8)][GaI4] (3), [K(D8)][GaI4] (4) and [NH4(D8)][GaI4] (5). All of the prepared compounds were analysed using single‐crystal X‐ray diffraction as well as multinuclear NMR spectroscopy. This reveals very different coordination modes in the compounds obtained.
Comparative Experimental Study on Improving Structural Performance of the Base Upright Profiles of Steel Storage Pallet Racks Under Operational Conditions
Authors: Taranu George , Ungureanu Viorel , Nagy Zsolt , Luca Septimiu-George , Alexa-Stratulat Mihai-Sergiu , Toma Ionut-Ovidiu
Published: May 2024

In recent decades, economic growth and globalization have spurred increased demand for efficient storage systems, leading to the extensive production of industrial racks from cold-formed steel profiles. Technological advances and research have significantly enhanced the optimization and mechanical efficiency of these profiles. However, older structures often require reassessment and strengthening to meet current and future load-bearing requirements, especially when systems are continuously in use and interventions must be minimized in terms of time and complexity. This paper investigates two strengthening solutions designed to improve the structural performance under various loading conditions, using experimental research to assess and understand the behavior of reinforced profiles. It presents a comparative analysis of the axial compression behavior of the base upright profiles of steel storage racks, each 1 m in length. A specific open cross-section with perforations was utilized, and a total of 13 specimens were tested: 5 unreinforced, 3 with ‘2L-shaped profiles’ for method 1, and 5 with ‘1C-shaped profile’ for method 2. For the strengthened profiles, both methods were secured inside the original profile using M8 bolts. The results demonstrate a 25% improvement in compression resistance capacity for method 2 and 4% for method 1, underscoring the effectiveness of these interventions.
Wind Aerodynamics and Related Energy Potential of Urban High-Rise Vertical Farms
Authors: Xie Simeng , Martinez-Vazquez Pedro , Baniotopoulos Charalampos
Published: May 2024

This paper presents the development of a benchmark vertical farm that could potentially enable the sustainable development of urban and rural areas. The investigation seeks to tackle global issues linked to sustainability development goals such as zero hunger, affordable clean energy, industry innovation and infrastructure, amongst others. Vertical farms enable plant-friendly environments in urban skyscrapers through agricultural techniques, often identified as consuming large amounts of energy. These facilities could be fully embedded into urban planning as clean energy sources such as solar and wind are fully utilised. This paper scrutinises the potential for wind energy utilisation in a vertical farm with different planting corridor widths. The study also seeks to clarify the potential for energy harvesting by identifying suitable micro wind turbines installed in the façade and roof. The vertical farm prototype is elliptical and has a total height of 108 m, 80 m width, and 60 m chord. This paper studied the prototype with corridor widths of 3 m, 4 m, 5 m, and 6 m, respectively. The maximum inlet wind speed was defined as 20 m/s, and the atmospheric boundary layer condition was applied to simulate an urban wind environment and observe the aerodynamics of the farm. The results showed that the benchmark building with a corridor of 5m-width has the best potential for wind energy harvesting, particularly when the wind turbines are located on the roof.
Disassembly and Structural Reuse Potential of Steel-Timber Shear Connections with Screws
Authors: Bompa Dan V. , Ungureanu Viorel , Elghazouli Ahmed Y. , Afsal Ahamed
Published: May 2024

The paper evaluates the disassembly capability and reuse potential of steel-timber shear connections. Experiments involving double shear configurations with coach screws of three diameters are detailed. Monotonic tests were first performed for each configuration to evaluate the stiffness, strength, and ductility. Counterparts were then tested under ten loading-unloading cycles, to 40% of the capacity obtained from the monotonic tests, to evaluate stiffness degradation characteristics, screw deformations, and cross-laminated timber (CLT) panel damage. After disassembly and measurements, the specimens were reassembled and tested up to failure. The measurements indicated that the secant stiffness enhances after the first loading cycle and is then largely constant to the tenth cycle. After disassembly, the screws had permanent deformations, and the timber panels indicated limited damage during the cyclic loading. The reassembled specimens had similar stiffness, strength, ductility, and failure modes as the monotonic test specimens. Based on test measurements, both the steel profile and the CLT panels have full structural reusability. The test results can be used as a measure for quantification of the structural reuse potential through an index that can be incorporated into established building circularity indicators.
Use of Textile Fiber Waste to Improve the Thermal and Mechanical Performance of Cement-Based Mortar
Authors: Ayed Rabeb , Borri Emiliano , Zsembinszki Gabriel , Bouadila Salwa , Cabeza Luisa F. , Lazaar Mariem
Published: May 2024

Improving the thermal properties of materials used in buildings is crucial to reducing energy demand and consumption. This study investigated the use of textile fiber waste in cement-based composites for construction applications. Mechanical and thermal characterizations were carried out to assess the behavior of cement mortars with different percentages of two types of textile fibers after 7 and 28 days of water hardening. The results show that the incorporation of fibers can significantly improve the thermal insulation capacity of buildings by reducing the thermal conductivity of cement mortar by up to 52%. In addition, the use of textile fibers can improve the mechanical strength of the cement mortar, especially with a high fiber content and a longer curing time.
Regenerative Approach in Sustainable Composite Structure Design for Building
Authors: Fakhfakh Mariem , Taieb Amin Hadj
Published: May 2024

By integrating living organisms and their intelligent capabilities at the heart of the design process, design evolves towards a creation in harmony with the surrounding nature. Therefore, the designer is led to reconsider the way they design sustainable solutions, capable not only of integrating but also of acting as living entities within their ecosystem. This approach promotes continuous interaction with the environment, fostering mutual enrichment where design and nature mutually enhance each other. Designers have the ability to reintegrate nature into the creation of materials and collaborate with natural resources. This reintegration fosters mutual positive impacts between natural and human systems. Such interactions lead designers to envision proactive scenarios for future habitats, merging scientific knowledge to co-evolve with nature. The design thus becomes a catalyst for transforming the design paradigm towards interconnectedness harmonious with the environment. In this context, it involves co-creation with living organisms from a perspective of bio-integrity rather than anthropocentrism, contributing to the regeneration of natural systems, restoration of human health, and preservation of biodiversity. While this approach presents a forward-thinking perspective, our empirical study seeks to demonstrate its potential implications in our daily lives and the real world. We have attempted to explore various methods and tests to incorporate the microorganism Ulva algae into the process of developing a living construction material, with the aim of promoting a locally regenerative approach.
Assessing the Impacts of Urban Circular Economy Practices on Economic Growth, Environmental Sustainability, and Social Benefits: A Case Study Analysis
Authors: Salles Adriana , Cervantes Camila , Bragança Luís
Published: May 2024

The urban circular economy is a highly effective approach to both waste management and the utilization of resources. Many cities have already adopted best practices based on circular economy principles. However, implementing such practices requires multi-stakeholder engagement, new business models, and collaboration between cities. Some successful strategies exist, ranging from urban agriculture and waste-to-energy to sharing economies, industrial symbiosis, and sustainable mobility, as well as eco-design, waste prevention, and the extension of product life. By adopting circular economy practices, cities can support economic growth, reduce environmental impact, and create social benefits, thereby moving towards a more sustainable future. In this regard, this study aims to analyze circular economy practices at the urban circularity level, by assessing their impacts on economic growth, environmental sustainability, and social benefits. To achieve this goal, a literature review is conducted to identify the most widely adopted circular strategies in cities. Comprehensive data collection, encompassing quantitative and qualitative measures, including economic indicators, environmental metrics, social assessments, and stakeholder feedback on the implementation process. Then the case study of Amsterdam is selected to demonstrate how urban circularity can be effective in achieving a balance between economic growth, environmental sustainability, and social benefits. Finally, this study also provides insights into the potential of urban circularity as an effective tool for sustainable urban development.
The Effect of Standardization on the Future of Sustainable Refurbishment of Existing Buildings
Authors: Leindecker Gerald
Published: May 2024

There is a vast building stock of existing buildings and the exchange rate is low (up to 0.2% per year). Therefore, there is a very strong need to deal with the existing building stock in respect to circularity. The effect of (new) regulations and standards on this volume for refurbishment and recycling of building materials is therefore crucial to meet the targets of CO2 reduction by increasing aspects of circularity overall to support environmental sustainability. The influence of standards towards the harmonization of technical requirements for refurbishment of existing buildings is therefore essential for wider implementation and acceptance in the market. There is, however, a gap identified between existing relevant standardization efforts and research in the field of refurbishment in the context of circularity. The effect of newly released standards and regulation will be analysed and identified barriers are discussed such as the generation and dissemination process of these standards.
Musical Meter as Shape: An Embodied Perspective on Metrical Trajectories and Curves
Authors: Haugen Mari Romarheim
Published: May 2024

The perception of musical rhythm includes not only thesonic rhythmbut also theendogenous reference structures,such asmeter. Musical meter is often described and understood as points in time or durations between such points. In this chapter, I argue that musical meter also has ashape. I propose that we perceive and make sense of musical meter based on our previous musical experiences involving meter-related bodily motion. In other words, the meter-related motion is integral to the perceived meter—they are the same. Meter thus has ashapethat relates to the embodied sensations of these movements. Also crucial is the notion that musical meter is conditioned by musical culture. This perspective on meter as shape is highly influenced by Godøy’smotor-mimetic perspective on music perceptionandmusical shape cognitionand concurs with the multimodal approach to sonic design that acknowledges motion as intrinsic to music performance and perception.
Unmixing the Wilson line defect CFT. Part I. Spectrum and kinematics
Authors: Ferrero Pietro , Meneghelli Carlo
Published: May 2024

Abstract

This is the first of a series of two papers in which we study the one-dimensional defect CFT defined by insertions of local operators along a $$\frac{1}{2}$$-BPS Wilson line in $$\mathcal{N}$$ = 4 super Yang-Mills. In this first paper we focus on the kinematical implications of invariance under the $$\mathfrak{o}\mathfrak{s}\mathfrak{p}\left({4}^{*}|4\right)$$ superconformal algebra preserved by the line. We study correlation functions involving both protected and unprotected supermultiplets and derive the associated superconformal blocks, using two types of superspace for short and long representations. We also discuss the spectrum of defect theories defined by the Wilson line, focusing in particular on fundamental lines in the planar limit: in this case we provide a detailed analysis of the type and number of states both at weak ’t Hooft coupling, via the free gauge theory description of the defect CFT, and at strong coupling, where there is a dual description via AdS/CFT. Focusing on the strongly-coupled regime, which will be subject to a detailed analysis using analytic bootstrap techniques in [1], we also develop a strategy that allows to explicitly build superconformal primary operators and their superconformal descendants in terms of the elementary fields in the AdS Lagrangian description. The explicit results will be used in [1] to address the problem of operators mixing at strong coupling. This paper and the companion [1] provide an extended version of the results presented in [2].
New non-supersymmetric flux vacua from generalised calibrations
Authors: Menet Vincent
Published: May 2024

Abstract

We construct a new class of non-supersymmetric ten-dimensional type II flux vacua, by studying first order differential equations which are deformations of the $$\mathcal{N}$$ = 1 supersymmetry conditions. We do so within the context of Generalised Complex Geometry, where there is a natural interpretation of the $$\mathcal{N}$$ = 1 supersymmetry conditions in terms of calibration conditions for probe D-branes, called D-string, domain-wall or space-filling branes, depending on them wrapping two, three or four non-compact dimensions. We focus on the class of non-supersymmetric vacua violating the D-string calibration condition, and write down their general equations of motion in the language of pure spinors. We solve them for a subclass of vacua, where the deformation of the calibration condition is dictated by the foliated geometry of the internal space. We also construct backgrounds violating both the domain-wall and D-string calibration conditions, generalising the one-parameter DWSB class of backgrounds introduced in Lüst et al. We present several explicit solutions with SU(2) and SU(3) structures, and we investigate briefly their associated low energy effective theories.
Asymptotic symmetries of SU(2) Yang-Mills-Higgs theory in Hamiltonian formulation
Authors: Janshen Lena , Giulini Domenico
Published: May 2024

Abstract

We investigate the asymptotic symmetry group of a SU(2)-Yang-Mills theory coupled to a Higgs field in the Hamiltonian formulation. This extends previous work on the asymptotic structure of pure electromagnetism by Henneaux and Troessaert, and on electromagnetism coupled to scalar fields and pure Yang-Mills fields by Tanzi and Giulini. We find that there are no obstructions to global electric and magnetic charges, though that is rather subtle in the magnetic case. Again it is the Hamiltionian implementation of boost symmetries that need a careful and technically subtle discussion of fall-off and parity conditions of all fields involved.
Temporal approximation of stochastic evolution equations with irregular nonlinearities
Authors: Klioba Katharina , Veraar Mark
Published: May 2024

In this paper, we prove convergence for contractive time discretisation schemes for semi-linear stochastic evolution equations with irregular Lipschitz nonlinearities, initial values, and additive or multiplicative Gaussian noise on 2-smooth Banach spaces X. The leading operator A is assumed to generate a strongly continuous semigroup S on X, and the focus is on non-parabolic problems. The main result concerns convergence of the uniform strong error$$\begin{aligned} \textrm{E}_{k}^{\infty } {:}{=}\Big (\mathbb {E}\sup _{j\in \{0, \ldots , N_k\}} \Vert U(t_j) - U^j\Vert _X^p\Big )^{1/p} \rightarrow 0\quad (k \rightarrow 0), \end{aligned}$$

E

k

∞

:
=

(

E

sup

j
∈
{
0
,
…
,

N
k

}

‖
U

(

t
j

)

-

U
j

‖

X
p

)

1
/
p

→
0

(
k
→
0
)

,

where $$p \in [2,\infty )$$

p
∈
[
2
,
∞
)

, U is the mild solution, $$U^j$$

U
j

is obtained from a time discretisation scheme, k is the step size, and $$N_k = T/k$$

N
k

=
T
/
k

for final time $$T>0$$

T
>
0

. This generalises previous results to a larger class of admissible nonlinearities and noise, as well as rough initial data from the Hilbert space case to more general spaces. We present a proof based on a regularisation argument. Within this scope, we extend previous quantified convergence results for more regular nonlinearity and noise from Hilbert to 2-smooth Banach spaces. The uniform strong error cannot be estimated in terms of the simpler pointwise strong error$$\begin{aligned} \textrm{E}_k {:}{=}\bigg (\sup _{j\in \{0,\ldots ,N_k\}}\mathbb {E}\Vert U(t_j) - U^{j}\Vert _X^p\bigg )^{1/p}, \end{aligned}$$

E
k

:
=

(

sup

j
∈
{
0
,
…
,

N
k

}

E

‖
U

(

t
j

)

-

U
j

‖

X
p

)

1
/
p

,

which most of the existing literature is concerned with. Our results are illustrated for a variant of the Schrödinger equation, for which previous convergence results were not applicable.
Multiresolution kernel matrix algebra
Authors: Harbrecht H. , Multerer M. , Schenk O. , Schwab Ch.
Published: May 2024

We propose a sparse algebra for samplet compressed kernel matrices to enable efficient scattered data analysis. We show that the compression of kernel matrices by means of samplets produces optimally sparse matrices in a certain S-format. The compression can be performed in cost and memory that scale essentially linearly with the number of data points for kernels of finite differentiability. The same holds true for the addition and multiplication of S-formatted matrices. We prove that the inverse of a kernel matrix, given that it exists, is compressible in the S-format as well. The use of selected inversion allows to directly compute the entries in the corresponding sparsity pattern. Moreover, S-formatted matrix operations enable the efficient, approximate computation of more complicated matrix functions such as $${\varvec{A}}^\alpha $$

A

α

or $$\exp ({\varvec{A}})$$

exp
(

A

)

of a matrix $${\varvec{A}}$$

A

. The matrix algebra is justified mathematically by pseudo differential calculus. As an application, we consider Gaussian process learning algorithms for implicit surfaces. Numerical results are presented to illustrate and quantify our findings.
Assessment of body mass-related covariates for rifampicin pharmacokinetics in healthy Caucasian volunteers
Authors: Bilal Muhammad , Ullah Sami , Jaehde Ulrich , Trueck Christina , Zaremba Dario , Wachall Bertil , Wargenau Manfred , Scheidel Bernhard , Wiesen Martin H. J. , Gazzaz Malaz , Chen Chunli , Büsker Sören , Fuhr Uwe , Taubert Max , Dokos Charalambos
Published: May 2024

Purpose

Currently, body weight-based dosing of rifampicin is recommended. But lately, fat-free mass (FFM) was reported to be superior to body weight (BW). The present evaluation aimed to assess the influence of body mass-related covariates on rifampicin’s pharmacokinetics (PK) parameters in more detail using non-linear mixed effects modeling (NLMEM).

Methods

Twenty-four healthy Caucasian volunteers were enrolled in a bioequivalence study, each receiving a test and a reference tablet of 600 mg of rifampicin separated by a wash-out period of at least 9 days. Monolix version 2023R1 was used for NLMEM. Monte Carlo simulations (MCS) were performed to visualize the relationship of body size descriptors to the exposure to rifampicin.

Results

A one-compartment model with nonlinear (Michaelis–Menten) elimination and zero-order absorption kinetics with a lag time best described the data. The covariate model including fat-free mass (FFM) on volume of distribution (V/F) and on maximum elimination rate (Vmax/F) lowered the objective function value (OFV) by 56.4. The second-best covariate model of sex on V/F and Vmax/F and BW on V/F reduced the OFV by 51.2. The decrease in unexplained inter-individual variability on Vmax/F in both covariate models was similar. For a given dose, MCS showed lower exposure to rifampicin with higher FFM and accordingly in males compared to females with the same BW and body height.

Conclusion

Our results indicate that beyond BW, body composition as reflected by FFM could also be relevant for optimized dosing of rifampicin. This assumption needs to be studied further in patients treated with rifampicin.
Aquablation versus HoLEP in patients with benign prostatic hyperplasia: a comparative prospective non-randomized study
Authors: Michaelis Jakob , Träger Max , Astheimer Sophie , von Büren Moritz , Gabele Elfi , Grabbert Markus , Halbich Jan , Kamps Marius , Klockenbusch Jonas , Noll Theresa , Pohlmann Phillippe , Schlager Daniel , Sigle August , Schönthaler Martin , Wilhelm Konrad , Gratzke Christian , Miernik Arkadiusz , Schöb Dominik Stefan
Published: May 2024

Purpose

The question of best surgical treatment for lower urinary tract symptoms (LUTS) due to benign prostate hyperplasia (BPH) remains controversial. We compared the outcomes of aquablation and holmium laser enucleation of the prostate ("HoLEP") in a prospective cohort.

Methods

Patients with BPH underwent aquablation or HoLEP according to their preference between June 2020 and April 2022. Prostate volume (“PV”), laboratory results, postvoid residual volume, uroflowmetry, IPSS, ICIQ-SF, MSHQ-EjD, EES and IIEF were evaluated preoperatively and at three, six and 12 months postoperatively. We also analyzed perioperative characteristics and complications via the Clavien Dindo („CD“) classification.

Results

We included 40 patients, 16 of whom underwent aquablation and 24 HoLEP. Mean age was 67 years (SD 7.4). Baseline characteristics were balanced across groups, except the HoLEP patients’ larger PV. IPSS fell from 20.3 (SD 7.1) at baseline to 6.3 (SD 4.2) at 12 months (p < 0.001) without differences between aquablation and HoLEP. HoLEP was associated with shorter operation time (59.5 (SD 18.6) vs. 87.2 (SD 14.8) minutes, p < 0.001) and led to better PV reduction over all timepoints. At three months, aquablation’s results were better regarding ejaculatory (p = 0.02, MSHQ-EjD) and continence function (p < 0.001, ICIQ-SF). Beyond three months, erectile, ejaculatory, continence function and LUTS reduction did not differ significantly between aquablation and HoLEP. CD ≥ grade 3b complications were noted in six patients in aquablation group while only one in HoLEP group (p =  < 0.01).

Conclusions

While aquablation revealed temporary benefits regarding ejaculation and continence at three months, HoLEP was superior concerning operation time, the safety profile and volumetric results.
The relationship between stone-free and patient position in retrograde intrarenal surgery: a randomized prospective study
Authors: Çanakcı Cengiz , Dinçer Erdinç , Can Utku , Coşkun Alper , Otbasan Bilal Kaan , Özkaptan Orkunt
Published: May 2024

Purpose

Residual fragments not removed with urinary stone surgery may become symptomatic. In this context, this study was carried out to investigate the effect of performing retrograde intrarenal surgery, which is conventionally performed in the lithotomy position, in the modified lithotomy position (Trend-side) on stone-free rates following the surgery.

Methods

This prospective study consisted of 100 patients with a single kidney stone smaller than 2 cm between 2021 and 2023. These patients were randomized into two groups of 50 patients each to be operated on in the conventional lithotomy and Trend-side positions. Variables were compared using independent t test for continuous variables and chi-square test for categorical variables.

Results

There was no significant difference between the lithotomy and Trend-side position groups in terms of preoperative size, density, location of the stone, and hydronephrosis degree. Stone-free rate was 72% (n = 36) in the lithotomy group and 92% (n = 46) in the Trend-side group. Hence, there was a significant difference between the groups in the stone-free rate in favor of the Trend-side group (p = 0.009). Fragmentation time was statistically significantly shorter in the Trend-side group than in the lithotomy group (34 ± 17 min vs. 43 ± 14 min; p = 0.006). There was no significant difference between the groups in postoperative complication rates.

Conclusion

Performing retrograde intrarenal surgery in the Trend-side position shortened the duration of fragmentation compared to the lithotomy position and was associated with higher stone-free rates. In conclusion, the Trend-side position can be safely preferred in patients undergoing retrograde intrarenal surgery due to kidney stones.
Soil contribution to the cobalamin (vitamin B12) supply of terrestrial organisms
Authors: Jörgensen Arne Matteo , Joergensen Rainer Georg
Published: May 2024

Cobalamin (Vitamin B12) is a cofactor for many enzymes, including those in bacteria, archaea, algae, and mammals. In humans, cobalamin deficiency can lead to pernicious anaemia as well as gastrointestinal and neurological disorders. In contrast to marine ecosystems, there is a great paucity of information on the role of soils and terrestrial plants in the supply of cobalt and cobalamin to microorganisms and animals. The content of cobalt cations in most soils is usually sufficient to maintain growth, and the density of cobalamin-producing soil prokaryotes is high in comparison to water bodies. The cobalt content of most soils is usually sufficient in comparison with water, and the density of cobalamin-producing soil prokaryotes is high. Therefore, terrestrial plants are an important cobalt source for cobalamin-producing rumen and gut prokaryotes. The major source of cobalamin for most other animals is the meat of ruminants as well as other animal-derived products, bacteria in insects, and coprophagy, e.g., by rodents. In addition, faecal deposits, and fertilizers as well as soil bacteria add to the cobalamin supply. However, those archaea and bacteria that do not produce cobalamin obtain this coenzyme or its analogues from the environment. Therefore, presence or absence of cobalamin-producing species in soil affects the whole soil microbiome. However, our knowledge concerning microbial producers and consumers of cobalamin in soils is still limited, despite some recent advances. The main reasons are a low cobalamin content in soils and challenging methods of determination. In this regard, advanced analytical knowledge and technical equipment are required, which are usually unavailable in soil laboratories. This review provides relevant methodological information on sample homogenization, extraction, concentration, and purification as well as analysis of cobalamin.
Real-world insights and outcomes related to ciclosporin A 0.1% cationic emulsion for the long-term treatment of dry eye disease in Germany: Country-level sub-analysis of the PERSPECTIVE study
Authors: Lanzl Ines , Deuter Christoph M E , Lorenz Katrin , Geerling Gerd ,   on behalf of the PERSPECTIVE German study group
Published: May 2024

Purpose

The PERSPECTIVE study was a real-world European, non-interventional, multicenter, observational study that evaluated the effectiveness, tolerability, and safety of ciclosporin A (CsA) 0.1% cationic emulsion (CE) in routine clinical practice as a treatment for adults with severe keratitis and dry eye disease (DED) that remained insufficiently controlled with artificial tears. This sub-analysis examined data from ophthalmology clinics in Germany to provide more precise insights into treatment patterns, outcomes, and clinical decision-making related to CsA 0.1% CE.

Methods

Study data were collected from adults starting CsA 0.1% CE (one drop in both eyes at bedtime) and followed up at Week 4, 12, and 24, and Month 12. The primary endpoint was mean change from baseline in corneal fluorescein staining (CFS) score (Oxford Grade Scale) at Month 12. Secondary endpoints examined the severity of ocular signs and symptoms, and adverse events (AEs).

Results

A total of 236 patients from 20 ophthalmology clinics in Germany participated in the PERSPECTIVE study (69.9% female; mean age 60.8 years). Following treatment with CsA 0.1% CE, patients experienced significant reductions in CFS score from Week 4, which were maintained through to Month 12 (P < 0.0001). From baseline, 81.6% of patients experienced an improvement in CFS score at Month 12. CsA 0.1% CE provided significant reductions in the severity of eyelid and conjunctival erythema at Month 12 compared with baseline (P < 0.001), as well as significant reductions in the severity of subjective ocular symptoms (all P ≤ 0.015). Safety data were consistent with the known safety profile of CsA 0.1% CE. Tolerability was rated as “satisfactory,” “good,” or “very good” by 97.2% of physicians and 95.7% of patients.

Conclusion

Outcomes in Germany were similar to those reported for the overall European study population and are indicative of the treatment results that ophthalmologists may expect to see with CsA 0.1% CE treatment in real-life clinical practice. Treatment with CsA 0.1% CE provided long-term improvements over 12 months and was generally well tolerated.
Allele-level visualization of transcription and chromatin by high-throughput imaging
Authors: Almansour Faisal , Keikhosravi Adib , Pegoraro Gianluca , Misteli Tom
Published: May 2024

The spatial arrangement of the genome within the nucleus is a pivotal aspect of cellular organization and function with implications for gene expression and regulation. While all genome organization features, such as loops, domains, and radial positioning, are nonrandom, they are characterized by a high degree of single-cell variability. Imaging approaches are ideally suited to visualize, measure, and study single-cell heterogeneity in genome organization. Here, we describe two methods for the detection of DNA and RNA of individual gene alleles by fluorescence in situ hybridization (FISH) in a high-throughput format. We have optimized combined DNA/RNA FISH approaches either using simultaneous or sequential detection of DNA and nascent RNA. These optimized DNA and RNA FISH protocols were implemented in a 384-well plate format alongside automated image and data analysis and enable accurate detection of individual gene alleles and their gene expression status across a large cell population. We successfully visualized MYC and EGFR DNA and nascent RNA with allele-level resolution in multiple cell types, and we determined the radial position of active and inactive MYC and EGFR alleles. These optimized DNA/RNA detection approaches are versatile and sensitive tools for mapping of chromatin features and gene activity at the single-allele level and at high throughput.