bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ Synthesis of S‐scheme Polymer Heterojunction Poly(phenyl‐1,3,5‐yl)‐benzene)/g‐C3N4 Composites for Efficient Removal of Rhodamine B
Authors: Mao Na , Zhang Yu‐hang , Li Junyan , Gao Ying
Published: July 2023

Poly(phenyl‐1,3,5‐yl)‐benzene/g‐C3N4 (PPB/g‐C3N4) catalysts were prepared by in situ for the removal of Rhodamine B from polluted water under visible light irradiation. In addition, the catalytic behavior of PPB/g‐C3N4 composites has been studied by using XRD, TEM, UV‐vis DRS and PL. The results show that PPB has been successfully loaded on g‐C3N4, PPB/g‐C3N4‐0.4 composite have good photo‐Fenton‐like catalytic performance. In the case of PPB/g‐C3N4+H2O2 composite, the RhB photo‐ removal efficiency was ∼96 % in 50 min. The removal rate of PPB/g‐C3N4+H2O2 composite is 9.4 times higher than that of pure g‐C3N4. Owing to the higher surface area and polymer heterojunction (PHJ), PPB/g‐C3N4‐0.4 composite have the superior photo‐Fenton‐like catalytic activity. Moreover, PPB/g‐C3N4 composite rendered excellent stability. Therefore, S‐scheme polymer heterojunction PPB/g‐C3N4 composite was synthesised without metal in situ, which are potential photo‐Fenton‐like catalyst for wastewater treatment under visible‐light irradiation, in which provided a new integration strategy.
Formation of the Short‐Range Order in Liquid Al−Ni−Sn Alloys
Authors: Yakovenko Olexiy , Kazimirov Volodymyr , Kashirina Yaroslavna , Sokolskii Volodymyr , Golovataya Nataliya , Kotova Natalia , Roik Oleksandr
Published: July 2023

Short‐range order (SRO) in the liquid Al−Ni−Sn alloys has been investigated using the X‐ray diffraction method and Reverse Monte Carlo simulations. Obtained results point out a micro‐inhomogeneous structure of Al−Sn−Ni melts with Sn content between 10 and 65 at.% due to the presence of atomic clusters with the structure of liquid Sn and atomic clusters with Ni−Sn coordination. The influence of the atomic size ratio (size factor) and pair atomic interactions (energy factor) on the short‐range order of the investigated ternary melts are discussed. There is a competition between Al and Sn atoms in the formation of the SRO around Ni atoms due to the difference in bond energy in Ni−Al and Ni−Sn pairs. This competition, as well as a bigger radius of Sn atoms, results in the formation of atomic clusters with liquid Sn‐like local atomic structure.
Fabrication of Ternary Ag/g‐C3N4/BiVO4 Composites with Enhanced Visible‐Light‐Driven Photocatalytic Activity toward Rhodamine B Elimination
Authors: Hoang Lan‐Anh T. , Le‐Duy Nhat , Nguyen Trinh Duy , Lee Taeyoon
Published: July 2023

BiVO4 and g‐C3N4 have gain attention for their potential in sustainable energy and environmental applications due to their visible light absorption properties. However, their limitations in terms of visible light absorption and electron‐hole separation have prompted efforts to enhance their energy utilization and reduce electron‐hole recombination. In our study, we investigated the fabrication of a ternary Ag/g‐C3N4/BiVO4 composite for Rhodamine B (RhB) degradation under visible light irradiation using a combination of photo‐deposition and calcination methods. Our findings demonstrate that the Ag/g‐C3N4/BiVO4 outperforms g‐C3N4, BiVO4, and g‐C3N4/BiVO4 in terms of RhB degradation rate. This improvement can be attributed to the improved light absorption and synergetic effects on charge transfer and photoelectron‐hole recombination resulting from the incorporation of Ag into the ternary system. This ternary Ag/g‐C3N4/BiVO4 composite has potential as a photocatalyst for the removal of organic pollutants due to its reasonable design and superior effectiveness.
An Aggregation‐Induced Change in the Fluorescence of Carbon Dots: Naked Eye Water Detection in a Selective Organic Solvent
Authors: Hazra Niladri , Paul Subir , Hazra Soumyajit , Banerjee Arindam
Published: July 2023

In this study, newly synthesized crystalline carbon dots shows the concentration and solvent‐dependent multicolor emission. The carbon dots have been characterized by several techniques like Fourier transformed infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), UV‐visible and fluorescence spectroscopy, and field emission gun transmission electron microscopy (FEG‐TEM). The high polarity of the solvents and the high concentration of the carbon dots help it to aggregate which opens up a new red‐shifted emission band. It has been revealed that the Förster resonance energy transfer (FRET) between the dispersed and aggregated state of the carbon dots becomes the actual cause behind this change. These carbon dots selectively shows the white light emission in the dioxane. The particular polarity of the dioxane selectively helps for the coexistence of the blue and greenish‐yellow emission bands with the same intensity which eventually turns the emission very much near to white light. It has been found that the very minute amount of water present in dioxane (0.1 % V/V) can change the emission nature of the carbon dots. This observation has finally helped these carbon dots for highly selective and perceptible water detection in dioxane.
A Greener Synthesis of Silver Nanoparticles Using Tea Leaf and Aloe Vera Leaf Extract for Catalytic Organic Dye Degradation Application
Authors: Sarkar Pankaj , Paul Sandip Kumar , Sahu Kashinath , Mandal Surajit , Islam Quazi Arif , Chakrabarty Rinku
Published: July 2023

The synthesis of inorganic nanoparticles via a green method has obtained a vast attention because of its simplicity, eco‐friendliness, less toxicity and cost‐effectiveness. In this present study, silver nanoparticle has been synthesized via the mixture of tea leaf and aloe vera leaf extract at room temperature. The synthesized silver nanoparticle was characterized in detail. Dynamic Light Scattering analysis shows an average particle size of 90 nm. The polyphenolic compounds present in the tea and aloe vera leaves act as the capping agent for the growth of synthesized nanoparticles. The isolated silver nanoparticles possess remarkable catalytic activity towards the degradation of organic dyes including methylene blue, methyl orange and rhodamine B. The catalyst also shows good cyclability for dye degradation along with chemical and structural stability. The present study suggests that silver nanoparticles synthesized by tea and aloe vera extract could be a potential stable catalyst for the degradation of various kinds of dyes and these types of plant extracts can be used to prepare efficient catalysts for various kinds of applications.
Insights into Reversible Sodium Intercalation in a Novel Sodium‐Deficient NASICON‐Type Structure:Na3.40□0.60Co0.5Fe0.5V(PO4)3
Authors: Hou Jingrong , Hadouchi Mohammed , Sui Lijun , Liu Jie , Tang Mingxue , Hu Zhiwei , Lin Hong‐Ji , Kuo Chang‐Yang , Chen Chien‐Te , Pao Chih‐Wen , Huang Yunhui , Ma Jiwei
Published: July 2023

The rational design of novel high‐performance cathode materials for sodium‐ion batteries is a challenge for the development of the renewable energy sector. Here, a new sodium‐deficient NASICON phosphate, namely Na3.40□0.60Co0.5Fe0.5V(PO4)3, demonstrating the excellent electrochemical performance is reported. The presence of Co allows a third Na+ to participate in the reaction thus exhibiting a high reversible capacity of ≈155 mAh g−1 in the voltage range of 2.0–4.0 V versus Na+/Na with a reversible single‐phase mechanism and a small volume shrinkage of ≈5.97% at 4.0 V. 23Na solid‐state nuclear magnetic resonance (NMR) combined with ex situ X‐ray diffraction (XRD) refinements provide evidence for a preferential Na+ insertion within the Na2 site. Furthermore, the enhanced sodium kinetics ascribed to Co‐substitution is also confirmed in combination with electrochemical impedance spectroscopy (EIS), galvanostatic intermittent titration technique (GITT), and theoretical calculation.
Stable and High‐Efficiency Perovskite Solar Cells Using Effective Additive Ytterbium Fluoride
Authors: Li Zhigang , Cao Yang , Feng Jiangshan , Lou Junjie , Liu Yucheng , Liu Shengzhong (Frank)
Published: July 2023

With better light utilization, larger tolerance factor, and higher power conversion efficiency (PCE), the HC(NH2)2+(FA)‐based perovskite is proven superior to the popular CH3NH3+ (MA)‐ and Cs‐based halide perovskites in solar cell applications. Unfortunately, limited by intrinsic defects within the FA‐based perovskite films, the perovskite films can be easily transformed into a yellow δ‐phase at room temperature in the fabrication process, a troublesome challenge for its further development. Here, ytterbium fluoride (YbF3) is introduced into the perovskite precursor for three objectives. First of all, the partial substitution of Yb3+ for Pb2+ in the perovskite lattice increases the tolerance factor of the perovskite lattice and facilitates the formation of the α phase. Second, YbF3 and DMSO in the solvent form a Lewis acid complex YbF3·DMSO, which can passivate the perovskite film, reduce defects, and improve device stability. Consequently, the YbF3 modified Perovskite solar cell exhibits a champion conversion efficiency of 24.53% and still maintains 90% of its initial efficiency after 60 days of air exposure under 30% relative humidity.
Insights on the Roles of Nitrogen Configuration in Enhancing the Performance of Electrocatalytic Methanol Oxidation over Pt Nanoparticles
Authors: Li Yanru , Li Hongwei , Zhao Yan , Ji Dong , Guo Peng , Li Guixian , Zhao Xinhong
Published: July 2023

Stabilization of the Pt in N‐doped carbon materials is an effective method to improve the performance of electrocatalytic methanol oxidation reaction (MOR). Nevertheless, the roles of different N configurations (pyridinic N, pyrrolic N, and graphitic N) toward the electrochemical performance of Pt‐based catalysts remain unclear. Herein, Density Functional Theory calculations are adopted to elucidate the synergistic promotion of MOR by different N‐configurations with Pt nanoparticles (NPs). Guided by the theoretical study, a series of MOR electrocatalysts with different ratios of pyridinic N and pyrrolic N (denoted as Pt/N‐CNT‐X (500, 600, 700, 800, and 900)) are designed and synthesized. Surprisingly, the electrocatalytic activity of Pt/N‐CNT‐600 with a suitable ratio of pyrrolic‐N and pyridinic‐N for MOR reaches 2394.7 mA mg−1Pt and 5515.8 mA mg−1Pt in acidic and alkaline media, respectively, which are superior to the Pt/CNTs, commercial Pt/C, and the ever‐reported Pt‐based electrocatalysts. The strong metal‐support interaction induced by the N‐doping is the crucial reason for the superior electrocatalytic performance. More importantly, the ability of pyrrolic‐N and pyridinic‐N in promoting the adsorption and oxidation of CH3OH and the oxidation of CO* is substantiated for the first time in methanol oxidation. This work provides new insights on the design of efficient electrocatalysts for MOR.
Freestanding, Freeform Metamolecule Fibers Tailoring Artificial Optical Magnetism
Authors: Kim Won‐Geun , Kim Hongyoon , Ko Byoungsu , Jeon Nara , Park Cherry , Oh Jin‐Woo , Rho Junsuk
Published: July 2023

Metamolecule clusters support various unique types of artificial electromagnetism at optical frequencies. However, the technological challenges regarding the freeform fabrication of freestanding metamolecule clusters with programmed geometries and multiple compositions remain unresolved. Here, the freeform, freestanding raspberry‐like metamolecule (RMM) fibers based on the directional guidance of a femtoliter meniscus are presented, resulting in the evaporative co‐assembly of silica nanoparticles and gold nanoparticles with the aid of 3D nanoprinting. This method offers a facile and universal pathway to shape RMM fibers in 3D, enabling versatile manipulation of near‐ and far‐field characteristics. In particular, the authors demonstrate the ability to decrease the scattering of the millimeter‐scale RMM fiber in visible spectrum. In addition, the influence of electric and magnetic dipole modes on the directional scattering of RMM fibers is investigated. These experiments show that the magnetic response of an individual RMM can be controlled by adjusting the filling factor of gold nanoparticles. The authors anticipate that this method will allow for unrestricted design and realization of nanophotonic structures, surpassing the limitations of conventional fabrication processes.
Grain Boundary Effects of Hierarchical Ni‐Fe (Oxy)hydroxide Nanosheets in Water Oxidation
Authors: Du Jing , Zhang Hong , Hu Wei , Li Zelong , Gao Wensheng , Wang Xiaomei , Li Can
Published: July 2023

The robust and scalable oxygen evolution electrocatalysts that can deliver high current densities at low applied potential is a great challenge for the large‐scale industrial application in hydrogen production. Here, the preparation of a grain‐boundary‐rich Ni‐Fe (oxy)hydroxide catalyst on Ni foam is reported using a scalable coating approach followed by a chemical precipitating treatment. This facile method effectively assembles the hierarchical Ni‐Fe (oxy)hydroxide nanosheet in the ultrasmall crystalline domains (<4 nm) with rich grain boundaries. The hierarchical nanosheet structure with the grain boundaries provides more accessible catalytic sites, facile charge, and mass transfer. Benefiting from the abundant grain boundaries in the hierarchical nanosheets, the as‐prepared Ni‐Fe (oxy)hydroxide electrodes deliver current densities of 500 and 1000 mA cm−2 at overpotentials of only 278 and 296 mV for the oxygen evolution reaction. The prepared electrode also exhibits long‐term durability at a high current density in alkaline conditions.
Stable Lithium–Sulfur Batteries Ensured by GeS2 and α‐S8 Lattice Matching During the Charge Process
Authors: Jiao Xun , Tang Xiaoxia , Li Jinrui , Li Cunpu , Liu Qingfei , Wei Zidong
Published: July 2023

The charge process of lithium–sulfur batteries (LSBs) is a process in which molecular polarity decreases and the volume shrinks gradually, which is the process most likely to cause lithium polysulfides (LiPSs) loss and interfacial collapse. In this work, GeS2 is utilized, whose (111) lattice plane exactly matches with the (113) lattice of α‐S8, to solve these problems. GeS2 can regulate the interconversion‐deposition behavior of S‐species during the charge process. Soluble LiPSs can be spontaneously adsorbed on the GeS2 surface, then obtain electrons and eventually convert to α‐S8 molecules. More importantly, the α‐S8 molecules will crystallize uniformly along the (111) lattice plane of GeS2 to maintain a stable cathode‐electrolyte interface. Therefore, outstanding charge/discharge LSBs are successfully accomplished.
Water‐Soluble Aggregation‐Induced Emission Luminogens with Near‐Infrared Emission for Advanced Phototheranostics
Authors: Shen Hanchen , Xu Changhuo , Ye Ruquan , Liu Tzu-Ming , Zhang Jianyu , Kwok Ryan T. K. , Lam Jacky W. Y. , Guo Zhihong , Sun Jianwei , Tang Ben Zhong
Published: July 2023

The development of water‐soluble aggregation‐induced emission luminogens (AIEgens) emitting in the near‐infrared (NIR) window holds promise for efficient biomedical applications. Nevertheless, synthesizing water‐soluble counterparts of NIR AIEgens presents difficulties due to their intrinsic hydrophobic properties. To address this issue, researchers have developed various molecular design strategies to improve the water solubility of NIR AIEgens. The integration of hydrophilic groups and targeting moieties is a crucial aspect of achieving precise phototheranostics. Here, diverse approaches to attain water‐soluble NIR AIEgens for biomedical applications are presented, and three commonly used strategies that involve decorating NIR AIEgens with positively or negatively charged groups, hydrophilic chains, and bioactive moieties are elaborated. These rational design strategies are believed to provide solutions for enhancing the water solubility and biological performance of NIR AIEgens in a single action. The remaining challenges and opportunities in this field are also discussed. The aim is to provide new insights into the design of water‐soluble NIR AIEgens and inspire more researchers to make significant contributions to this promising research area.
Multicompartment Nanostructures as Templates for Multimetallic Hybrid Materials
Authors: Tjaberings Stefanie , Heidelmann Markus , Franzka Steffen , Gröschel André H.
Published: July 2023

ABC triblock terpolymers are promising soft templates for organic/inorganic hybrids because of their ability to form nanostructures with complex shapes, multiple compartments, and precisely localized chemistry. Exemplified on multicompartment nanofibers (MCNFs) of triblock terpolymers, it is demonstrated that microdomains can be selectively loaded, thereby giving access to nanoscale multimetallic hybrid materials. MCNFs with micrometer length, homogenous diameter (90 nm), and a helix‐on‐cylinder morphology are formed from polystyrene‐block‐polybutadiene‐block‐poly(tert‐butyl methacrylate) (PS‐b‐PB‐b‐PT). After postmodification (cross‐linking/hydrolysis), selective loading with FeCl3, PdCl2, H2PtCl6, AgNO3, CuCl2, or ZnCl2 leads to a variety of hybrid MCNFs analyzed by transmission electron microscopy, scanning transmission electron microscopy, electron tomography, energy‐dispersive X‐ray spectroscopy, and atomic force microscopy. Mild sulfonation of the PS shell to polystyrene sulfonate renders the MNCFs water‐dispersible and allows the formation of mixed‐bimetallic Pt/Pd/Pt@MCNFs and trimetallic Pt/Pd/Ag@MCNFs. It is demonstrated that the order of loading is key to successfully create multimetallic nanostructures. These and other structures can become useful for energy applications as well as in photo‐ and electrocatalysis.
SnF2‐Doped Cs2SnI6 Ordered Vacancy Double Perovskite for Photovoltaic Applications
Authors: Murshed Rubaiya , Thornton Sarah , Walkons Curtis , Koh Jung Jae , Bansal Shubhra
Published: July 2023

Air‐stable p‐type SnF2:Cs2SnI6 with a bandgap of 1.6 eV has been demonstrated as a promising material for Pb‐free halide perovskite solar cells. Crystalline Cs2SnI6 phase is obtained with CsI, SnI2, and SnF2 salts in gamma‐butyrolactone solvent, but not with dimethyl sulfoxide and N,N‐dimethylformamide solvents. Cs2SnI6 is found to be stable for at least 1000 h at 100 °C when dark annealed in nitrogen atmosphere. In this study, Cs2SnI6 has been used in a superstrate n–i–p planar device structure enabled by a spin‐coated absorber thickness of ≈2 μm on a chemical bath deposited Zn(O,S) electron transport layer. The best device power conversion efficiency reported here is 5.18% with VOC of 0.81 V, 9.28 mA cm−2 JSC, and 68% fill factor. The dark saturation current and diode ideality factor are estimated as 1.5 × 10−3 mA cm−2 and 2.18, respectively. The devices exhibit a high VOC deficit and low short‐circuit current density due to high bulk and interface recombination. Device efficiency can be expected to increase with improvement in material and interface quality, charge transport, and device engineering.
Solubility of MoS2 and Graphite in Molten Salt: Flowers, Faceted Crystals, or Exfoliation?
Authors: Ohayon–Lavi Avia , John Subish , Lavi Adi , Leibovitch Yelena , Vradman Leonid , Ruse Efrat , Regev Oren
Published: July 2023

2D materials are of interest in various applications such as energy conversion, storage, and sensing. These materials are prepared by bottom‐up or top‐down methods that are difficult to control and suffer from low yield. Synthesis in molten salt is suggested as an alternative in which the balance between exfoliation and solubility is explored. It is demonstrated that when a pellet of 2D material is insoluble in molten salt (graphite in any salt), it is exfoliated. For low solubility (MoS2 in NaCl/KCl), the 2D material nucleates and grows into a small flowerlike structure composed of thin MoS2 sheets through Ostwald ripening. For high solubility in the molten salt (MoS2 in CsCl), it forms larger flowers. Herein, the molten salt treatment of high and low surface area MoS2 (micron‐size particles and a single large pellet, respectively) is compared. The particles yielded facet MoS2 crystals through dissolution–nucleation–recrystallization process and the pellet yielded flowers. Herein, methods for synthesizing 2D materials with controllable size and shape are promoted by simple molten salt treatment that opens an avenue to the development of soluble (MoS2) and non‐soluble (graphite) materials with different morphologies in a simple and affordable way.
Using state-space models to estimate recreational angling effort and infer processes that regulate angler dynamics
Authors: McCormick Joshua L. , Heckel John W.
Published: July 2023

Objective

State-space models are a flexible modeling approach and are often fit to ecological time series data exhibiting temporal autocorrelation. Traditionally, angler effort data collected using on-site creel surveys are analyzed using design-based methods. With some exceptions, state-space models are rarely used to model creel survey data that are also generally a time series of temporally autocorrelated counts.

Methods

In this study, we demonstrated how to fit state-space models to a time series of angler counts in 11 sections of three trout fisheries in Idaho. The basic model was extended to make inference about processes that may regulate angling dynamics, such as “population growth rate” of angling effort and recreational carrying capacity.

Result

Estimated angling effort varied from 21,179 h in the lowermost section of the Henrys Fork Snake River to 199,457 h in the uppermost section of the South Fork Snake River. The finite population growth rate of angling effort was 1.82 when transitioning from a weekday to a weekend, suggesting that angling effort was 1.82 times greater, on average, on Saturdays than on Fridays, and the population growth rate was 0.38 (i.e., 0.38 times smaller) when transitioning from a Sunday to a Monday. Estimated carrying capacity among fishery sections varied from 129 daily hours of angling effort on the Big Lost River to 693 h on the middle section of the South Fork Snake River. Carrying capacity was 1.88 times higher on fishery sections that had ≥0.5 access points/km than on sections with <0.5 access points/km.

Conclusion

The state-space models used in this study can be modified or extended to fit a variety of data types or can be used to evaluate additional hypotheses regarding the angling process.
The effect of green synthesis of TiO2 nanoparticles/collagen/HA scaffold in bone regeneration: As an animal study
Authors: Yazdanian Alireza , Jahandideh Alireza , Hesaraki Saeed
Published: July 2023

Background

The bone defects cannot heal by themselves when their range exceeds the critical size defect (CSD). In clinical treatment, significant bone defects are often caused by trauma, developmental deformity, tumour resection and infection.

Objectives

The purpose of this study was to investigate the effect of green synthesis of TiO2 from propolis extract/collagen/HA (Hydroxyapatite) scaffolds on bone regeneration in rats.

Methods

Water uptake, biodegradability, porosity and biodegradation of the scaffolds were evaluated after they were synthesised using freeze‐dry method. Cell viability by MTT assay was then evaluated. During the 4, 8 and 12 weeks following the scaffold implantation, the bone regeneration was evaluated using macroscopic and microscopic tests to determine the effectiveness of green synthesis of TiO2 from propolis extract/collagen/HA scaffolds.

Results

Compared to the HA/Coll scaffold, ProTiO2/HA/Coll scaffold was reduced porosity, water absorption and degradability porosity. Based on in vitro tests, both synthetic scaffolds induced cell growth and were less toxic and stimulated cell growth. Based on histopathological testing, the ProTiO2/HA/Coll scaffolds formed high levels of bone during 12 weeks in comparison with HA/Coll and control group.

Conclusions

ProTiO2/HA/Coll composite can be used in regenerative medicine, bone fillers and scaffolds. As a result, this research suggests that ProTiO2/HA/Coll composites could be promising candidates for bone regeneration.
Small x physics beyond eikonal approximation: an effective Hamiltonian approach
Authors: Li Ming
Published: July 2023

Abstract

Understanding the spin structure of hadrons in the small x regime is an important direction to unravel the spin puzzle in hadronic physics. To include spin degrees of freedom in the small x regime requires going beyond the usual eikonal approximation in high energy QCD. We developed an effective Hamiltonian approach to study spin related observables in the small x regime using the shockwave formalism. The small-x effective Hamiltonian incorporates both quark and gluon propagators in the background fields and the background field induced interaction vertices up to next-to-eikonal order. A novel feature of sub-eikonal interactions is the background gluon field induced gluon radiation inside the shockwave. Its relation to chromo-electrically polarized Wilson line correlator is established both in small x helicity evolution and in longitudinal double-spin asymmetry for gluon production.
Boundary and domain wall theories of 2d generalized quantum double model
Authors: Jia Zhian , Kaszlikowski Dagomir , Tan Sheng
Published: July 2023

Abstract

The generalized quantum double lattice realization of 2d topological orders based on Hopf algebras is discussed in this work. Both left-module and right-module constructions are investigated. The ribbon operators and the classification of topological excitations based on the representations of the quantum double of Hopf algebras are discussed. To generalize the model to a 2d surface with boundaries and surface defects, we present a systematic construction of the boundary Hamiltonian and domain wall Hamiltonian. The algebraic data behind the gapped boundary and domain wall are comodule algebras and bicomodule algebras. The topological excitations in the boundary and domain wall are classified by bimodules over these algebras. The ribbon operator realization of boundary-bulk duality is also discussed. Finally, via the Hopf tensor network representation of the quantum many-body states, we solve the ground state of the model in the presence of the boundary and domain wall.
The cosmological switchback effect
Authors: Baiguera Stefano , Berman Rotem , Chapman Shira , Myers Robert C.
Published: July 2023

Abstract

The volume behind the black hole horizon was suggested as a holographic dual for the quantum computational complexity of the boundary state in AdS/CFT. This identification is strongly motivated by the switchback effect: a characteristic delay of complexity growth in reaction to an inserted perturbation, modelled as a shockwave in the bulk. Recent proposals of de Sitter (dS) holography suggest that a dual theory could be living on a stretched horizon near the cosmological horizon. We study how the spacetime volume behind the cosmological horizon in Schwarzschild-dS space reacts to the insertion of shockwaves in an attempt to characterize the properties of this dual theory. We demonstrate that a switchback effect can be observed in dS space. That is, the growth of complexity is delayed in reaction to a perturbation. This delay is longer for earlier shocks and depends on a scrambling time which is logarithmic in the strength of the shockwave and proportional to the inverse temperature of the cosmological dS horizon. This behavior is very similar to what happens for AdS black holes, albeit the geometric origin of the effect is somewhat different.
Bootstrapping string dynamics in the 6d 𝒩 = (2, 0) theories
Authors: Meneghelli Carlo , Trépanier Maxime
Published: July 2023

Abstract

We present two complementary approaches to calculating the 2-point function of stress tensors in the presence of a 1/2 BPS surface defect of the 6d 𝒩 = (2, 0) theories. First, we use analytical bootstrap techniques at large N to obtain the first nontrivial correction to this correlator, from which we extract the defect CFT (dCFT) data characterising the 2d dCFT of the 1/2 BPS plane. Along the way we derive a supersymmetric inversion formula, obtain the relevant superconformal blocks and check that crossing symmetry is satisfied. Notably our result features a holomorphic function whose appearance is related to the chiral algebra construction of Beem, Rastelli and van Rees. Second, we use that chiral algebra description to obtain exact results for the BPS sector of the dCFT, valid at any N and for any choice of surface operator. These results provide a window into the dynamics of strings of the mysterious 6d theories.
Large N analytical functional bootstrap. Part I. 1D CFTs and total positivity
Authors: Li Zhijin
Published: July 2023

Abstract

We initiate the analytical functional bootstrap study of conformal field theories with large N limits. In this first paper we particularly focus on the 1D O(N) vector bootstrap. We obtain a remarkably simple bootstrap equation from the O(N) vector crossing equations in the large N limit. The numerical conformal bootstrap bound is saturated by the generalized free field theories, while its extremal functional actions do not converge to any non-vanishing limit. We study the analytical extremal functionals of this crossing equation, for which the total positivity of the SL(2, ℝ) conformal block plays a critical role. We prove the SL(2, ℝ) conformal block is totally positive in the limits with large ∆ or small 1 − z and show that the total positivity is violated below a critical value $$ {\Delta }_{\textrm{TP}}^{\ast } $$

∆
TP
∗

≈ 0.32315626. The SL(2, ℝ) conformal block forms a surprisingly sophisticated mathematical structure, which for instance can violate total positivity at the order 10−5654 for a normal value ∆ = 0.1627! We construct a series of analytical functionals {αM} which satisfy the bootstrap positive conditions up to a range ∆ ⩽ ΛM. The functionals {αM} have a trivial large M limit. However, due to total positivity, they can approach the large M limit in a way consistent with the bootstrap positive conditions for arbitrarily high ΛM. Moreover, in the region ∆ ⩽ ΛM, the analytical functional actions are consistent with the numerical bootstrap results, therefore it clarifies the positive structure in the crossing equation analytically. Our result provides a concrete example to illustrate how the analytical properties of the conformal block lead to nontrivial bootstrap bounds. We expect this work paves the way for large N analytical functional bootstrap in higher dimensions.
Pion screening mass at finite chemical potential
Authors: Thakkar Rishabh , Hegde Prasad
Published: July 2023

Abstract

We present a method to compute the responses of meson screening masses to the chemical potential by Taylor expanding the correlator using lattice QCD simulation. We start by comparing the free theory lattice results with the analytical expression. Then, using symmetry arguments, we obtain an expression for the correlator in a series of the chemical potential at finite temperature. Using this, we obtain the lowest order correction to the screening mass at a finite chemical potential for temperatures around 2.5 GeV. Our lattice analysis is limited to isoscalar chemical potential for the pseudoscalar channel. The calculations were performed using (2+1)-flavors of the Highly Improved Staggered Quark (HISQ/tree) action, with the ratio of the strange quark mass to the light quark mass ms/mℓ = 20 corresponding to pion masses of 160 MeV.
Interpolations of monoidal categories and algebraic structures by invariant theory
Authors: Meir Ehud
Published: July 2023

In this paper we give a general construction of symmetric monoidal categories that generalizes Deligne’s interpolated categories, the categories introduced by Knop, and the recent TQFT construction of Khovanov, Ostrik, and Kononov. The categories we will consider are generated by an algebraic structure. In a previous work by the author a universal ring of invariants $$\mathfrak {U}$$
U
for algebraic structures of a specific type was constructed. It was shown that any algebraic structure of this type in $${\text {Vec}}_K$$

Vec
K

gives rise to a character $$\chi :\mathfrak {U}\rightarrow K$$

χ
:
U
→
K

. In this paper we consider algebraic structure in general symmetric monoidal categories, not only in $${\text {Vec}}_K$$

Vec
K

, and general characters on $$\mathfrak {U}$$
U
. From any character $$\chi :\mathfrak {U}\rightarrow K$$

χ
:
U
→
K

we construct a symmetric monoidal category $${\mathcal {C}}_{\chi }$$

C
χ

, analogous to the universal construction from TQFT. We then give necessary and sufficient conditions for a given character to arise from a structure in an abelian category with finite dimensional hom-spaces. We call such characters good characters. We show that if $$\chi $$
χ
is good then $${\mathcal {C}}_{\chi }$$

C
χ

is abelian and semisimple, and that the set of good characters forms a K-algebra. We also show that the categories $${\mathcal {C}}_{\chi }$$

C
χ

contain all categories of the form $${\text {Rep}}(G)$$

Rep
(
G
)

, where G is reductive. The construction of $${\mathcal {C}}_{\chi }$$

C
χ

gives a way to interpolate algebraic structures, and also symmetric monoidal categories, in a way that generalizes Deligne’s categories $${\text {Rep}}(S_t)$$

Rep
(

S
t

)

, $${\text {Rep}}({\text {GL}}_t(K))$$

Rep
(

GL
t

(
K
)

)

, and $${\text {Rep}}(\text {O}_t)$$

Rep
(

O
t

)

. We also explain how one can recover the recent construction of 2 dimensional TQFT of Khovanov, Ostrik, and Kononov, by the methods presented here. We give new examples, of interpolations of the categories $${\text {Rep}}({\text {Aut}}_{{\mathcal {O}}}(M))$$

Rep
(

Aut
O

(
M
)

)

where $${\mathcal {O}}$$
O
is a discrete valuation ring with a finite residue field, and M is a finite module over it. We also generalize the construction of wreath products with $$S_t$$

S
t

, which was introduced by Knop.
Associations of Alzheimer's-related plasma biomarkers with cognitive decline in Parkinson's disease
Authors: Mizutani Yasuaki , Ohdake Reiko , Tatebe Harutsugu , Higashi Atsuhiro , Shima Sayuri , Ueda Akihiro , Ito Mizuki , Tokuda Takahiko , Watanabe Hirohisa
Published: July 2023

Background

Parkinson’s disease (PD) is associated with cognitive decline through multiple mechanisms, including Alzheimer’s disease (AD) pathology and cortical Lewy body involvement. However, its underlying mechanisms remain unclear. Recently, AD-related plasma biomarkers have emerged as potential tools for predicting abnormal pathological protein accumulation. We aimed to investigate the association between AD-related plasma biomarkers and cognitive decline in PD patients.

Methods

Plasma biomarkers were measured in 70 PD patients (49 with nondemented Parkinson’s disease (PDND) and 21 with Parkinson’s disease dementia (PDD)) and 38 healthy controls (HCs) using a single-molecule array. The study evaluated (1) the correlation between plasma biomarkers and clinical parameters, (2) receiver operating characteristic curves and areas under the curve to evaluate the discrimination capacity of plasma biomarkers among groups, and (3) a generalized linear model to analyze associations with Addenbrooke’s Cognitive Examination-Revised and Montreal Cognitive Assessment-Japanese version scores.

Results

Plasma glial fibrillary acidic protein significantly correlated with cognitive function tests, including all subdomains, with a notable increase in the PDD group compared with the HC and PDND groups, while plasma neurofilament light chain captured both cognitive decline and disease severity in the PDND and PDD groups. Plasma beta-amyloid 42/40 and pholphorylated-tau181 indicated AD pathology in the PDD group, but plasma beta-amyloid 42/40 was increased in the PDND group compared with HCs and decreased in the PDD group compared with the PDND group.

Conclusions

AD-related plasma biomarkers may predict cognitive decline in PD and uncover underlying mechanisms suggesting astrocytic pathologies related to cognitive decline in PD.
Exercise-induced myocardial T1 increase and right ventricular dysfunction in recreational cyclists: a CMR study
Authors: Ghekiere Olivier , Herbots Lieven , Peters Benjamin , Berg Baptiste Vande , Dresselaers Tom , Franssen Wouter , Padovani Bernard , Ducreux Dorothee , Ferrari Emile , Nchimi Alain , Demanez Sophie , De Bosscher Ruben , Willems Rik , Heidbuchel Hein , La Gerche Andre , Claessen Guido , Bogaert Jan , Eijnde Bert O.
Published: July 2023

Purpose

Although cardiac troponin I (cTnI) increase following strenuous exercise has been observed, the development of exercise-induced myocardial edema remains unclear. Cardiac magnetic resonance (CMR) native T1/T2 mapping is sensitive to the pathological increase of myocardial water content. Therefore, we evaluated exercise-induced acute myocardial changes in recreational cyclists by incorporating biomarkers, echocardiography and CMR.

Methods

Nineteen male recreational participants (age: 48 ± 5 years) cycled the ‘L’étape du tour de France” (EDT) 2021’ (175 km, 3600 altimeters). One week before the race, a maximal graded cycling test was conducted to determine individual heart rate (HR) training zones. One day before and 3–6 h post-exercise 3 T CMR and echocardiography were performed to assess myocardial native T1/T2 relaxation times and cardiac function, and blood samples were collected. All participants were asked to cycle 2 h around their anaerobic gas exchange threshold (HR zone 4).

Results

Eighteen participants completed the EDT stage in 537 ± 58 min, including 154 ± 61 min of cycling time in HR zone 4. Post-race right ventricular (RV) dysfunction with reduced strain and increased volumes (p < 0.05) and borderline significant left ventricular global longitudinal strain reduction (p = 0.05) were observed. Post-exercise cTnI (0.75 ± 5.1 ng/l to 69.9 ± 41.6 ng/l; p < 0.001) and T1 relaxation times (1133 ± 48 ms to 1182 ± 46 ms, p < 0.001) increased significantly with no significant change in T2 (p = 0.474). cTnI release correlated with increase in T1 relaxation time (p = 0.002; r = 0.703), post-race RV dysfunction (p < 0.05; r = 0.562) and longer cycling in HR zone 4 (p < 0.05; r = 0.607).

Conclusion

Strenuous exercise causes early post-race cTnI increase, increased T1 relaxation time and RV dysfunction in recreational cyclists, which showed interdependent correlation. The long-term clinical significance of these changes needs further investigation.

Trial registration numbers and date

NCT 04940650 06/18/2021. NCT 05138003 06/18/2021.
Simulated Annealing is a Polynomial-Time Approximation Scheme for the Minimum Spanning Tree Problem
Authors: Doerr Benjamin , Rajabi Amirhossein , Witt Carsten
Published: July 2023

We prove that Simulated Annealing with an appropriate cooling schedule computes arbitrarily tight constant-factor approximations to the minimum spanning tree problem in polynomial time. This result was conjectured by Wegener (Automata, Languages and Programming, ICALP, Berlin, 2005). More precisely, denoting by $$n, m, w_{\max }$$

n
,
m
,

w
max

, and $$w_{\min }$$

w
min

the number of vertices and edges as well as the maximum and minimum edge weight of the MST instance, we prove that simulated annealing with initial temperature $$T_0 \ge w_{\max }$$

T
0

≥

w
max

and multiplicative cooling schedule with factor $$1-1/\ell $$

1
-
1
/
ℓ

, where $$\ell = \omega (mn\ln (m))$$

ℓ
=
ω
(
m
n
ln
(
m
)
)

, with probability at least $$1-1/m$$

1
-
1
/
m

computes in time $$O(\ell (\ln \ln (\ell ) + \ln (T_0/w_{\min }) ))$$

O
(
ℓ

(
ln
ln

(
ℓ
)

+
ln

(

T
0

/

w
min

)

)

)

a spanning tree with weight at most $$1+\kappa $$

1
+
κ

times the optimum weight, where $$1+\kappa = \frac{(1+o(1))\ln (\ell m)}{\ln (\ell ) -\ln (mn\ln (m))}$$

1
+
κ
=

(
1
+
o
(
1
)
)
ln
(
ℓ
m
)

ln
(
ℓ
)
-
ln
(
m
n
ln
(
m
)
)

. Consequently, for any $$\epsilon >0$$

ϵ
>
0

, we can choose $$\ell $$
ℓ
in such a way that a $$(1+\epsilon )$$

(
1
+
ϵ
)

-approximation is found in time $$O((mn\ln (n))^{1+1/\epsilon +o(1)}(\ln \ln n + \ln (T_0/w_{\min })))$$

O
(

(
m
n
ln

(
n
)

)

1
+
1
/
ϵ
+
o
(
1
)

(
ln
ln
n
+
ln

(

T
0

/

w
min

)

)

)

with probability at least $$1-1/m$$

1
-
1
/
m

. In the special case of so-called $$(1+\epsilon )$$

(
1
+
ϵ
)

-separated weights, this algorithm computes an optimal solution (again in time $$O( (mn\ln (n))^{1+1/\epsilon +o(1)}(\ln \ln n + \ln (T_0/w_{\min })))$$

O
(

(
m
n
ln

(
n
)

)

1
+
1
/
ϵ
+
o
(
1
)

(
ln
ln
n
+
ln

(

T
0

/

w
min

)

)

)

), which is a significant speed-up over Wegener’s runtime guarantee of $$O(m^{8 + 8/\epsilon })$$

O
(

m

8
+
8
/
ϵ

)

. Our tighter upper bound also admits the result that in some situations a hybridization of simulated annealing and the $${(1 + 1)}$$

(
1
+
1
)

 EA can lead to stronger runtime guarantees than either algorithm alone.
The use of generative adversarial networks for multi-site one-class follicular lymphoma classification
Authors: Somaratne Upeka Vianthi , Wong Kok Wai , Parry Jeremy , Laga Hamid
Published: July 2023

Recent advances in digital technologies have lowered the costs and improved the quality of digital pathology Whole Slide Images (WSI), opening the door to apply Machine Learning (ML) techniques to assist in cancer diagnosis. ML, including Deep Learning (DL), has produced impressive results in diverse image classification tasks in pathology, such as predicting clinical outcomes in lung cancer and inferring regional gene expression signatures. Despite these promising results, the uptake of ML as a common diagnostic tool in pathology remains limited. A major obstacle is the insufficient labelled data for training neural networks and other classifiers, especially for new sites where models have not been established yet. Recently, image synthesis from small, labelled datasets using Generative Adversarial Networks (GAN) has been used successfully to create high-performing classification models. Considering the domain shift and complexity in annotating data, we investigated an approach based on GAN that minimized the differences in WSI between large public data archive sites and a much smaller data archives at the new sites. The proposed approach allows the tuning of a deep learning classification model for the class of interest to be improved using a small training set available at the new sites. This paper utilizes GAN with the one-class classification concept to model the class of interest data. This approach minimizes the need for large amounts of labelled data from the new site to train the network. The GAN generates synthesized one-class WSI images to jointly train the classifier with WSIs available from the new sites. We tested the proposed approach for follicular lymphoma data of a new site by utilizing the data archives from different sites. The synthetic images for the one-class data generated from the data obtained from different sites with minimum amount of data from the new site have resulted in a significant improvement of 15% for the Area Under the curve (AUC) for the new site that we want to establish a new follicular lymphoma classifier. The test results have shown that the classifier can perform well without the need to obtain more training data from the test site, by utilizing GAN to generate the synthetic data from all existing data in the archives from all the sites.
Rising incidence of acute total hip arthroplasty for primary and adjunctive treatment of acetabular fracture in older and middle-aged adults
Authors: Patterson Joseph T. , Wier Julian , Kumaran Pranit , Adamczyk Andrew
Published: July 2023

Background

Acute total hip arthroplasty (THA) may be an alternative or an adjuvant to internal fixation for surgical treatment of acetabular fractures. We investigate recent trends in the operative management of acetabular fractures. We hypothesize that the incidence of acute THA for acetabular fractures has increased over time.

Methods

4569 middle-aged (45–64 years) and older adults (≥ 65 years) who received acute operative management of an acetabular fracture within 3 weeks of admission between 2010 and 2020 were identified from the United States Nationwide Inpatient Sample database. Treatment was classified as open reduction internal fixation (ORIF), THA, or combined ORIF and THA (ORIF + THA). Patients were stratified by age ≥ 65 years old. Associations between demographic factors and the incidence of each procedure over the study period were modeled using linear regression.

Results

The relative incidence of treatments was 80.9% ORIF, 12.1% THA, and 7.0% ORIF + THA. Among patients aged 45–64 years old, THA increased 4.8% [R2 = 0.62; β1 = 0.6% (95% Confidence Interval (CI) 0.2–0.9%)] and ORIF + THA increased 2.6% [R2 = 0.73; β1 = 0.3% (95% CI 0.2–0.4%)], while the use of ORIF decreased 7.4% [R2 = 0.75; β1 = −0.9% (95% CI −1.2 to −0.5%)]. Among patients ≥ 65 years old, THA increased 16.5% [R2 = 0.87; β1 = 1.7% (95% CI 1.2–2.2%)] and ORIF + THA increased 5.0% [R2 = 0.38, β1 = 0.6% (95% CI 0.0–1.3%)], while ORIF decreased 21.5% [R2 = 0.75; β1 = −2.4% (95% CI −3.45 to −1.3%)].

Conclusion

The treatment of acetabular fractures with acute THA has increased in the last decade, particularly among older adults.
Assessment of selected muscle damage markers and zonulin concentration after maximum-intensity exercise in men with type 1 diabetes treated with a personal insulin pump
Authors: Matejko Bartłomiej , Tota Łukasz , Morawska-Tota Małgorzata , Pałka Tomasz , Malecki Maciej T. , Klupa Tomasz
Published: July 2023

Aim

Exercise-induced muscle damage depends on exercise intensity and duration and on individual susceptibility. Mechanical and metabolic stress may disturb the intestinal microflora. The study evaluated selected muscle damage markers and zonulin concentration after maximum-intensity exercise in type 1 diabetes (T1D) men compared with healthy controls.

Methods

The study involved 16 T1D participants and 28 controls matched by age (22.7 [21.3–25.1] vs. 22.6 [20.9–26.3] years), body mass index (24.2 ± 1.6 vs. 24.2 ± 1.9 kg/m2), and body fat percentage (16.1 ± 5.2 vs. 14.9 ± 4.6%). The T1D group had 11.3 ± 5.1 years of diabetes duration and a suboptimal mean glycated haemoglobin level of 7.2 ± 1.1%. The subjects underwent a graded running treadmill test until exhaustion. Lactate concentration was assessed in arterialized blood at baseline and 3 and 20 min after the test. Cortisol, testosterone, tumour necrosis factor α, myoglobin, lactate dehydrogenase, zonulin, and vitamin D levels were evaluated in cubital fossa vein blood before and 60 min after the test.

Results

T1D patients presented higher baseline zonulin, myoglobin concentration, testosterone/cortisol ratio, and lower maximal oxygen uptake. On adjusting for the baseline values, the groups differed in zonulin, lactate dehydrogenase, and myoglobin levels, testosterone/cortisol ratio, and lactate concentration determined 20 min after exercise (P < 0.05).

Conclusion

Maximum-intensity exercise increased muscle and intestinal damage in T1D participants. In patients with lower physical activity, very-high-intensity exercise should be recommended with caution. Observing the anabolic-catabolic index may help individualize effort intensity in T1D individuals.