bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of rainfall intensity and underground pore density on the soil erosion mechanism of sloping maize farmland in a typical karst area of SW China
Authors: Wang Yong , Dai Quanhou , Ding Pengwei , Yao Yiwen , Li Kuaifen , Yan Youjin , Yi Xingsong , He Jie
Published: December 2022

The rainfall intensity, slope, and underground pore density are major factors affecting the soil erosion of maize‐covered karst slopes. We studied the erosion process of maize‐covered karst slopes and the influencing mechanism of soil erosion on these slopes under different rainfall intensities, slopes, and underground pore density via simulated rainfall tests. The results are as follows: (1) No runoff was observed on the slope surface under light rainfall (30 mm hr−1); instead, subsurface flow was predominant. However, runoff from the surface and subsurface flows under moderate rainfall (60 mm hr−1) increased with the rainfall intensity. The average surface runoff under extreme rainfall (90 mm hr−1) was 2.3‐times that under moderate rainfall. In addition, the average subsurface runoff under extreme rainfall was 1.6‐ and 3.5‐times that under moderate rainfall and light rainfall, respectively. The total amounts of surface and subsurface soil losses increased as the rainfall intensity increased. The surface and subsurface soil losses from light to moderate and extreme rainfall events increased by 258% and 151%, respectively. The soil loss from the surface was 5.3‐times greater than that from the subsurface, indicating that the erosion of maize‐covered karst slopes mainly occurs on the surface and that the subsurface loss is relatively small. (2) As the slope angle increased, the runoff, sediment yield, and proportion of erosion on the surface increased, and vice versa. (3) The subsurface runoff and sediment yield increased as the underground pore density increased, while the opposite occurred on the surface. Multiple regression analysis showed that the rainfall intensity is the most critical factor affecting the soil erosion of maize ‐covered slopes in karst areas, followed by the slope, while the influence of the underground pore density is small.
Bacterial communities in proso millet root‐associated compartments are regulated by growth period and mulching regime
Authors: Tian Lixin , Cao Xinxin , Gao Xiaoli , Feng Baili
Published: December 2022

Mulching regimes have a promoted impact on the soil hydrothermal environments and crop productions. However, the time‐dependent variations in root‐associated microbial communities under distinct mulching regimes in the Loess Plateau have not been thoroughly explored. Here, we investigated the regulatory impacts of plastic film mulching (FM) and ridge‐furrow mulching system (RF) on the microbial community compositions, diversities, and ecological networks in the distinct compartments (e.g., root, rhizosphere, and bulk soil) at jointing and flowering periods of proso millet, and we compared these two regimes to no mulching (NM). Mulching regimes improved the bulk and rhizosphere soil quality at jointing period, whereas reduced them at flowering period. Bacterial structure and composition of the three compartments were significantly influenced by growth periods and mulching regimes. Furthermore, mulching regimes effectively increased the alpha diversities of rhizosphere and root communities at flowering period. Soil temperature and total N were the most essential variables affecting the bulk soil and rhizosphere community structure, respectively. With the growth and development of proso millet, the network complexity and stability increased, and the abundance of different modules in the three compartments were regulated by mulching regimes. Proteobacteria and Acidobacteriota were the keystone species at jointing period, whereas, at flowering period, only Proteobacteria were the keystone species. In addition, FM regime significantly increased the species interaction and abundance of keystone taxa than those of non‐mulching at both periods. These results highlighted that mulching regimes were observed to be a recommended selection for improving soil quality, regulating bacterial diversity and structure, and stabilizing the species interaction, thereby providing guidance for choosing the ideal cultivation techniques from the perspective of microbial ecology in the Loess Plateau.
Real‐Time On‐Demand Design of Circuit‐Analog Plasmonic Stack Metamaterials by Divide‐and‐Conquer Deep Learning
Authors: Xiong Jiankai , Shen Jiaqing , Gao Yuan , Chen Yingshi , Ou Jun‐Yu , Liu Qing Huo , Zhu Jinfeng
Published: December 2022

The design of plasmonic stack metamaterials (PSMs) is critical due to their promising potentials in the fields of optical absorbers, sensors, and thermal irradiation. Compared with the classical circuit‐based optimization, the design by deep learning (DL) has attracted greater attention, since it is not essential to obtain their equivalent circuit parameters. Currently, a DL model for their higher‐precision design, especially with complicated spectral features, is still quite in demand. Here, a divide‐and‐conquer DL model based on a bidirectional artificial neural network is proposed. As proof‐of‐concept examples, the PSMs consisting of two metal/dielectric/metal/dielectric subwavelength stacks are adopted to demonstrate the validity of the paradigm. It demonstrates a significant prediction error reduction of 37.5% with the 47.8% decrease of training parameters than the conventional method in the forward network, which supports a powerful inverse design from spectra to PSM structures. Furthermore, a flexible tool based on the free customer definition, which facilitates the real‐time design of PSMs with various circuit‐analog functions, is developed. The fabrication and measurement experiments verify the design performance of the method. The study enhances the precision and convenience of on‐demand circuit‐analog PSMs and will provide a guide for fast high‐performance inverse design of many other metamaterials.
Metallopolymers with Ferrocenyl and TEMPO Radical Units and Thermoelectric Properties of their Composites with Single‐Wall Carbon Nanotubes
Authors: Lau Mei‐Tung , Li Zikang , Wong Wai‐Yeung
Published: December 2022

Radical‐containing metallopolymers (RCMPs) represent a promising class of thermoelectric (TE) materials. Here, three RCMPs with the ferrocenyl moiety R1, R2, and R3 are synthesized. Single‐walled carbon nanotubes (SWCNTs) are used to form the composites with each of these RCMPs and the morphological, spectroscopic electrochemical, and thermoelectric properties of the three polymer composites are studied. Composite R3/SWCNT shows the highest electrical conductivity (675.7 ± 36.0 S cm−1) and power factor (174.3 ± 5.5 µW m−1 K−2) compared to R1 and R2. It is shown that when the ferrocenyl unit is incorporated into the main chain of the polymer backbone, it reveals a better TE performance than that with the ferrocenyl unit at the periphery.
Development of CO2‐Philic Blended Membranes Using PIM–PI and PIM–PEG/PPG
Authors: Jeong Insu , Hossain Iqubal , Husna Asmaul , Kim Tae‐Hyun
Published: December 2022

Blending is a simple method through which one can effectively tailor new polymers exhibiting the properties of their parent ones. Because the original properties of polymers are maintained after blending, various studies have used these films as gas separation membranes. In this study, a new CO2 separation membrane is developed by physically mixing a polymer of intrinsic microporosity (PIM) with high gas permeability, polyimide (PIM‐PI), as the hard segment and CO2‐philic PIM‐poly(ethylene glycol)/poly(propylene glycol), or PIM‐PEG/PPG, as the soft segment. Prepared by adding 5 mol.% of PIM‐PEG/PPG to PIM‐PI, the blended membrane PPB‐5, with a tensile strength of 54 MPa and 35.5% elongation at break, shows better mechanical properties than commercial high‐performance polymer membranes developed for gas separation, PEG‐based blended membranes, and corresponding copolymer membranes with similar compositions developed in a previous study. In addition, it shows high CO2 permeability (1552.6 Barrer) and CO2/N2 selectivity (29.3) due to the well‐developed microphase separation characteristics originating from the optimal two‐component composition, and the gas separation performance is close to the Robeson (2008) upper bound.
Unconditionally strong energy stable scheme for Cahn–Hilliard equation with second‐order temporal accuracy
Authors: Lee Seunggyu
Published: December 2022

We propose an unconditionally gradient stable scheme for solving the Cahn–Hilliard equation with second‐order accuracy in time using the effective time‐step analysis. The conventional convex splitting scheme is one of the most well‐known methods for solving gradient flows, and it guarantees both energy stability and first‐order accuracy in time. Recently, there are some researches, which are extended to the second‐order accuracy; however, most of results provide the proof of energy stability for a modified (pseudo) energy or in a weak sense. In this paper, we prove the energy stability of the proposed method with respect to the Ginzburg–Landau free energy functional. Moreover, the unique solvability, mass conservation, and accuracy of the proposed scheme are also proven based on the convex splitting approach. The numerical experiments are presented to show convergence rate, mass conservation, energy stability, and phase separation are in good agreement with the theory.
High‐performance binary blazed grating coupler with a mixed structure of germanium and zinc selenide
Authors: Li Junwei , Wei Kai , Zhang Yudong , Li Xiqi , Cui Hao
Published: December 2022

A high‐performance binary blazed grating coupler with a mixed germanium and zinc selenide structure on a Ge‐on‐Si platform is proposed for a perfectly vertical coupling. To obtain high coupling efficiency, grating parameters are repeatedly and carefully optimized. For the perfectly vertical coupler with transverse‐magnetic polarized incident light, the coupling efficiency is 49.5% at the wavelength of 8 μm with a 1‐dB bandwidth of 110 nm. Thus, the coupling efficiency‐bandwidth product is beyond 54.5 nm. Furthermore, the manufacturing route of the grating is discussed, which adopts the combination of electron‐beam lithography and three‐dimensional nanoprinting.
4 × 25 Gb/s PAM4 optical transmitter for micro‐ring modulator with thermal control
Authors: Chen Yinghao , Chen Yingmei , Guo Chao , Fan Wentian , Zhu En , Hu Zhengfei
Published: December 2022

The explosive growth of bandwidth demands of data center and super‐computing systems spur the appliance and development of optoelectronic‐based solutions such as micro‐ring modulator (MRM) transmitters, and advanced modulation schemes such as four‐level pulse‐amplitude modulation (PAM4). In this paper, a 4 × 25 Gb/s PAM4 MRM transmitter fabricated in 0.13 μm SiGe BiCMOS technology is presented. It consists of four‐channel MRM driver and thermal control loop. Capacitor and resistor degeneration techniques and inductor peaking techniques are adopted to expand channel bandwidth. Meanwhile, the predistortion technique is utilized to compensate for MRM nonlinearity, and auto gain control (AGC) circuits to enable the MRM driver to realize a fixed differential output swing of 3.5 Vpp. Furthermore, a thermal control method based on analog to digital converter, digital to analog converter, and logic control circuits is proposed to compensate for the temperature sensitivity of MRM. The measurement results show that the 25 Gb/s nonreturn‐to‐zero optical eye achieves an extinction ratio of 5.63 dB, and the PAM4 eye can be observed up to 40 Gb/s.
The Push for Racial Equity in Child Welfare: Can Blind Removals Reduce Disproportionality?
Authors: Jason Baron E. , Goldstein Ezra G. , Ryan Joseph
Published: December 2022

We conduct the first quantitative analysis of “blind removals,” an increasingly popular reform that seeks to reduce the over‐representation of Black children in foster care by eliminating biases in the removal decisions of investigators. We first show that over‐representation in most foster care systems is driven by Black children being substantially more likely than White children to be investigated for maltreatment to begin with. Conditional on initial rates of investigation, investigators remove White and Black children similarly. Second, we find no evidence that blind removals impacted the already small racial disparities in the removal decision, but they substantially increased time to removal.
Dual‐Layer Semi‐Insulating GaN Substrates Doped with Fe, C, or Mn
Authors: Iso Kenji , Ikeda Hirotaka , Mochizuki Tae , Odani Takafumi , Izumisawa Satoru
Published: December 2022

The compatibility of impurity doping and the suppression of residual stress are crucial for fabricating a semi‐insulating GaN (SI‐GaN) substrate. Herein, a new method to fabricate several SI‐GaN substrates, including a dual‐layer SI‐GaN substrate comprising upper ≈100 μm‐thick GaN doped with Fe, C, or Mn and a lower ≈300 μm‐thick unintentionally doped GaN, using hydride vapor‐phase epitaxy is proposed. As a result, substrates doped with Fe, C, or Mn are successfully produced without cracks and pits. Resistivities around a doping concentration of ≈1018 cm−3 are up to 6.6 × 108, >1012, and >1012 Ω cm at room temperature, respectively. The residual stress of the dual‐layer SI‐GaN film is also evaluated.
Disturbance rejection control of multiple integrators system by bounded linear extended observer based output feedback
Authors: Zhang Kai , Zhou Bin , Yang Xuefei
Published: December 2022

This paper is concerned with the disturbance rejection control problem of multiple integrators systems subject to actuator saturation and external disturbance. By using the solutions to a class of parametric Lyapunov equations (PLEs), extended observer based bounded linear output feedback controller is designed to solve the considered problem. By constructing a novel Lyapunov function and using the properties of the PLE, the stability of the closed‐loop system is proved and the domain of attraction is estimated. In order to improve control performance, bounded linear time‐varying output feedback controller is also proposed such that the state of the closed‐loop system tends to zero as the time approaches to the prescribed setting time which is independent of the initial conditions and can be assigned in advance. In addition, some comparisons of the proposed methods to existing results are given. Finally, numerical examples verify the effectiveness of the proposed methods.
Influence of the filling ratio of vial in chemical surface and physicochemical properties of ZnO nanoparticles obtained by planetary ball milling process
Authors: Gonzalez E. David , Ospina Rogelio , Gonzalez‐Estrada Octavio Andres , Botero Julian , Botero Monica Andrea
Published: December 2022

The production of nanoparticles (Np) is an important sector in current technological development. Processes such as high‐energy grinding are among the most promising because of their high efficiency and low energy cost. In this sense, the filling ratio of vial (FRV) is one of the most interesting and poorly studied process variables that can optimize the production of Np on a large scale. In the present work, dry ZnO Np are produced, with different FRV values (40%, 38%, 23%, and 10%), as well as wet samples. The results show that the variation of the FRV allows to generate an energetic increase of the grinding, modifying the morphology, the particle size, and the surface area of the ZnO powders, without generating structural or chemical changes. The X‐ray diffraction (XRD) results show the presence of the zincite phase (hexagonal) with a variation in crystallinity depending on the FRV, which is due to the deformation of the Np during the process. The XPS results showed a slight chemical shift (variation in binding energy) as a function of grinding because of the activation shown by deformation. UV–VIS analyses showed a marked increase in the magnitude of absorbed intensity for all analyzed samples compared with the commercial powder. These results confirm that FRV is a sensitive parameter in the process of obtaining ZnO Np by the planetary mill technique, which allows efficient control of its characteristics for a given application.
An Extreme‐Environment‐Resistant Self‐Healing Anti‐Icing Coating
Authors: Li Ruiqi , Tian Shu , Tian Yunqing , Wang Jiancheng , Xu Sijia , Yang Kai , Yang Jing , Zhang Lei
Published: December 2022

Anti‐icing coatings on outdoor infrastructures and transportations inevitably suffer from surface injuries, especially in extreme weather events (e.g., freezing weather or acid rain). The coating surface damage can result in anti‐icing performance loss or even icing promotion. The development of anti‐icing coatings that enables self‐healing in extreme conditions is highly desired but still challenging. Herein, an extreme‐environment‐resistant self‐healing anti‐icing coating is developed by integrating fluorinated graphene (FG) into a supramolecular polymeric matrix. The coating exhibits both anti‐icing and deicing performance (ice nucleation temperature is ≈−30.3 °C; ice shear strength is ≈48.7 kPa), mainly attributable to the hydrophobic FG and silicone‐based supramolecular material. Notably, owing to the crosslinking polymeric network with various dynamic bonds, this coating can sustain anti‐icing/deicing performance after autonomous self‐healing under harsh conditions including low temperature (−20 °C), strong acid (pH = 0), and strong alkali (pH = 14) environments. This coating paves the way to meet the anti‐icing demand in open air, especially for the infrastructures in polar regions or acid/alkali environments.
Research Advances in Amorphous‐Crystalline Heterostructures Toward Efficient Electrochemical Applications
Authors: Jin Yachao , Zhang Mengxian , Song Li , Zhang Mingdao
Published: December 2022

Interface engineering of heterostructures has proven a promising strategy to effectively modulate their physicochemical properties and further improve the electrochemical performance for various applications. In this context related research of the newly proposed amorphous‐crystalline heterostructures have lately surged since they combine the superior advantages of amorphous‐ and crystalline‐phase structures, showing unusual atomic arrangements in heterointerfaces. Nonetheless, there has been much less efforts in systematic analysis and summary of the amorphous‐crystalline heterostructures to examine their complicated interfacial interactions and elusory active sites. The critical structure‐activity correlation and electrocatalytic mechanism remain rather elusive. In this review, the recent advances of amorphous‐crystalline heterostructures in electrochemical energy conversion and storage fields are amply discussed and presented, along with remarks on the challenges and perspectives. Initially, the fundamental characteristics of amorphous‐crystalline heterostructures are introduced to provide scientific viewpoints for structural understanding. Subsequently, the superiorities and current achievements of amorphous‐crystalline heterostructures as highly efficient electrocatalysts/electrodes for hydrogen evolution reaction, oxygen evolution reaction, supercapacitor, lithium‐ion battery, and lithium‐sulfur battery applications are elaborated. At the end of this review, future outlooks and opportunities on amorphous‐crystalline heterostructures are also put forward to promote their further development and application in the field of clean energy.
Remarkably Selective Propylene–Propane Separation Using a Copper Scorpionate
Authors: Noonikara‐Poyil Anurag , Cui Hui , Wang Bin , Shi Yanshu , Chen Banglin , Dias H. V. Rasika
Published: December 2022

Propylene is a crucial building block to produce many industrial‐scale chemicals including polypropylene. The separation of propylene from propane to reach the high‐purity levels needed for downstream applications is a difficult task due to the close similarities in their physical properties. The olefin/paraffin separation including that involving propylene mainly relies on highly energy‐intensive distillation processes and accounts for nearly 0.3% of the global energy consumption. The utility of a copper complex supported by a fluorinated bis(pyrazolyl)borate is demonstrated to accomplish the separation of propylene from propane repeatedly, under mild conditions with high selectivity. Complete characterization of a rare, copper(I) propylene complex is also reported including the molecular structure.
Universal Capacitance Boost—Smart Surface Nanoengineering by Zwitterionic Molecules for 2D MXene Supercapacitor
Authors: Děkanovský Lukáš , Azadmanjiri Jalal , Havlík Martin , Bhupender Pal , Šturala Jiří , Mazánek Vlastimil , Michalcová Alena , Zeng Lunjie , Olsson Eva , Khezri Bahareh , Sofer Zdeněk
Published: December 2022

Two‐dimensional nanomaterials, as one of the most widely used substrates for energy storage devices, have achieved great success in terms of the overall capacity. Despite the extensive research effort dedicated to this field, there are still major challenges concerning capacitance modulation and stability of the 2D materials that need to be overcome. Doping of the crystal structures, pillaring methods and 3D structuring of electrodes have been proposed to improve the material properties. However, these strategies are usually accompanied by a significant increase in the cost of the entire material preparation process and also a lack of the versatility for modification of the various types of the chemical structures. Hence in this work, versatile, cheap, and environmentally friendly method for the enhancement of the electrochemical parameter of various MXene‐based supercapacitors (Ti3C2, Nb2C, and V2C), coated with functional and charged organic molecules (zwitterions—ZW) is introduced. The MXene‐organic hybrid strategy significantly increases the ionic absorption (capacitance boost) and also forms a passivation layer on the oxidation‐prone surface of the MXene through the covalent bonds. Therefore, this work demonstrates a new, cost‐effective, and versatile approach (MXene‐organic hybrid strategy) for the design and fabrication of hybrid MXene‐base electrode materials for energy storage/conversion systems.
Assessing the Effects of Steel Composition on Surface Cracks in Continuous Casting with Solidification Simulations and Phenomenological Quality Criteria for Quality Prediction Applications
Authors: Norrena Julius , Louhenkilpi Seppo , Visuri Ville-Valtteri , Alatarvas Tuomas , Bogdanoff Agne , Fabritius Timo
Published: December 2022

Crack formation is an issue that significantly undermines the quality and productivity of steel production. In previous studies, a solidification and microstructure model known as InterDendritic Solidification (IDS) has been developed and implemented in various slab casters in Finland. Numerous quality criteria have been derived from the model outputs to identify the general phenomena which increase the risks of defect formation in different steel grades. The aim of this study is to study the feasibility of these criteria in providing input data for predicting quality in a group of defect‐prone steel grades with rule‐based decision‐making and machine learning algorithms. To this end, three steel grades are studied by utilizing measured compositions and comparing the quality criteria with plant data regarding reported defects. The computations are carried out by coupling IDS with a fundamental model for simulating heat transfer (Tempsimu) in continuous casting. The results indicate that for the studied steel grades, phenomenological quality criteria can be applied to predict the formation of cracks and other defects. Trends contributing to increased risks of defect formation are identified for all the studied steel grades, and possibilities for avoiding defects by changes in the compositions of these steel grades are also proposed.
Experimental study on seismic behavior of circular steel tube confined reinforced self‐stressing steel slag concrete columns
Authors: Bu Shuangshuang , Yu Feng , Chen Taiyao , Fang Yuan , Qin Yin
Published: December 2022

Low‐cycle reversed loading test were conducted on 10 circular steel tube confined reinforced self‐stressing steel slag concrete columns and four circular steel tube confined reinforced steel slag concrete (SSC) columns, to investigate the influence of the shear span ratio, axial compression ratio, diameter‐thickness ratio and expansion ratio of SSC on the seismic performance of the specimens. The results indicated that the crushing of core SSC at the bottom of columns and yielding of longitudinal reinforcement dominated the specimens damage. Fine circumferential tensile cracks without development trend along the height direction appeared at the non‐shear plane of the columns. The hysteretic curves were generally full, which denoted that the specimens had good seismic behavior. With the increase of the axial compression ratio, diameter‐thickness ratio, or decrease of the shear span ratio, the strength degradation was more severe and the ductility reduced. The stiffness degradation rate was accelerated with the increase of the axial compression ratio, or reduction of the expansion ratio of SSC or shear span ratio. In addition, as the axial compression ratio or expansion ratio of SSC raised, or the shear span ratio reduced, the ductility of the specimens decreased and the growth of the energy dissipation coefficient was accelerated.
Impact behavior of low strength concrete slab strengthened with fan type anchored carbon fiber‐reinforced polymer strips
Authors: Çalışkan Özlem , Aras Murat , Yılmaz Tolga , Anıl Özgür , Erdem R. Tuğrul
Published: December 2022

This study investigated the behavior of slabs produced with low compressive strength concrete without reinforcements under the effect of sudden dynamic impact loading. In addition, an experimental study was conducted by proposing a strengthening method with anchored carbon fiber‐reinforced polymer (CFRP) strips to strengthen the nonreinforced slabs with low‐strength concrete against sudden dynamic impact loads to improve their performance. The variables examined in the experimental study were the placement of the CFRP strips adhered to the concrete slabs for strengthening purposes and anchors in the strips. A constant energy level of impact loading was applied to the concrete slab test specimens with the authors' free weight drop test setup. The acceleration‐time, displacement‐time, strain‐time, and applied impact loading‐time measurements on the concrete slabs were examined, and comments were made about the strengthening method applied to the slab test specimens. In addition, numerical analysis of the tested concrete slabs with ABAQUS finite element software was performed, and the results were compared with the experimental results. In the comparison, it was investigated to what extent numerical analysis and this type of impact analysis can be done realistically and compatible with the experimental results. Within the scope of the study, the strengthening method applied with fan‐type anchored CFRP strips significantly improved and increased the impact performance of concrete slabs produced with low‐strength concrete.
Assessment and strengthening of reinforced concrete bridges with half‐joint deterioration
Authors: Granata Michele Fabio , La Mendola Lidia , Messina Davide , Recupero Antonino
Published: December 2022

Existing Niagara‐type concrete cantilever bridges, which in Italy are called Gerber bridges, suffer from degradation due to reinforcement corrosion and a consequent reduced load‐bearing capacity. The assessment of these structures is therefore an important part of the procedures for analyzing the state of existing bridges and any interventions required for their retrofitting. In particular, safety against failure of the half‐joint must be evaluated with respect to the behavior of the entire bridge and its state of conservation, determining what the conditions are that lead to failure, in terms of loads, state of stress, and possibly cracking state. This evaluation has to be carried out considering the configuration of the bridge through local and global models, in the presence of the crossbeam between the main girders or the prestressing tendons that can modify the behavior of the Gerber saddle, compared to that expected for a simple dapped‐end beam. To do this, it is necessary to combine the in situ investigations with reliable analytical and numerical models, which can correctly interpret the structural behavior of the bridge, determining the critical aspects for safety. The approach followed in this study was to combine the strut‐and‐tie models with nonlinear finite element models that can provide reliable information to the engineer who deals with the assessment and subsequently the conception of rehabilitation, in combination with in situ investigations and material tests. This was carried out through two different case studies in which the shape of the Gerber saddle, the presence of the crossbeam, and the presence of prestressing characterize the behavior and highlight the degree of safety and that of structural robustness. The results of the analyses carried out show that the presence of prestressing and a careful design with the use of large amounts of reinforcement can lead in some cases to high safety factors and consequently to a good level of robustness. They also show that the structural behavior can vary significantly according to the level of reinforcement corrosion: this is an aspect that can only be correctly assessed with the use of different models with different degrees of refinement. Finally, a proposal for global structural rehabilitation is presented by closing saddles, changing the static scheme to the continuous beam, and supplying external prestressing to strengthen the deck.
Cadmium induces mitochondrial dysfunction via SIRT1 suppression‐mediated oxidative stress in neuronal cells
Authors: Wen Shuangquan , Xu Mingchang , Zhang Wenhua , Song Ruilong , Zou Hui , Gu Jianhong , Liu Xuezhong , Bian Jianchun , Liu Zongping , Yuan Yan
Published: December 2022

Cadmium is a widespread environmental contaminant and its neurotoxicity has raised serious concerns. Mitochondrial dysfunction is a key event in Cd‐induced nervous system disease; however, the exact molecular mechanism involved has not been fully elucidated. Increasing evidences have shown that Sirtuin 1 (SIRT1) is the key target protein impaired in Cd‐induced mitochondrial dysfunction. In this study, the role of SIRT1 in Cd‐induced mitochondrial dysfunction and cell death and the underlying mechanisms were evaluated in vitro using PC12 cells and primary rat cerebral cortical neurons. The results showed that Cd exposure caused cell death by inhibiting SIRT1 expression, thus inducing oxidative stress and mitochondrial dysfunction in vitro. However, inhibition of oxidative stress by the antioxidant puerarin alleviated Cd‐induced mitochondrial dysfunction. Furthermore, activation of SIRT1 using the agonist Srt1720 significantly abolished Cd‐induced oxidative stress and mitochondrial dysfunction and ultimately alleviated Cd‐induced neuronal cell death. Collectively, our data indicate that Cd induced mitochondrial dysfunction via SIRT1 suppression‐mediated oxidative stress, leading to the death of PC12 cells and primary rat cerebral cortical neurons. These findings suggest a novel mechanism for Cd‐induced neurotoxicity.
Delta shock wave as limits of vanishing viscosity for zero‐pressure gas dynamics with energy conservation law
Authors: Li Shiwei
Published: December 2022

This paper studies the system of conservation laws of mass, momentum, and energy in zero‐pressure gas dynamics. By the vanishing viscosity method, the stability of the solutions involving delta shock wave with Dirac delta functions developing in both state variables is established.
Level set‐based shape optimization approach for the inverse optical tomography problem
Authors: Belhachmi Zakaria , Dhif Rabeb , Meftahi Houcine
Published: December 2022

We consider the inverse problem of recovering piecewise scattering and piecewise absorption jump sets from boundary measurements and from a single measurement of the absorbed energy. We propose a reconstruction method based on a shape optimization approach combined with the level set techniques. Our main result includes the partial shape derivatives of two different shape functionals, using differentiability properties of the min‐sup combined with a function space parameterization technique. In particular, it reveals the expression of the distributed partial shape derivative in tensor form. Based on the computed distributed partial shape derivatives, we introduce and implement a numerical approach based on the gradient approach and level set method. We present several numerical experiments to show the efficiency of the method both for exact reconstruction data and for realistic data with noise.
Transforming Navier‐stokes equation to a fourth order nonlinear differential equation for the study of electrolyte flow in a circular microchannel
Authors: Layeghi Mohammad , Gorji Mohammad
Published: December 2022

In this paper, analytical solutions are derived for the study of steady‐state electrolyte flow in a circular microchannel under the simultaneous effects of an external electric field and uniform wall injection. The Navier‐Stokes equations containing an axial linear electric body force are transformed to a fourth‐order nonlinear differential equation and solved analytically using a series solution method. The most important results are presented and discussed in terms of radial Reynolds number and a fundamental non‐dimensional electric field parameter. The Electrical Double Layer theory is employed to model the effects of external electric field. Analytical relations are given for velocity profiles, exit flow rate, and total pressure drop in the microchannel. The results show that a high‐intensity electric field can completely reverse the velocity profile or make it more flat in the presence of wall injection. This electric effect can be used in practical applications to control the shear stress, heat, or mass transfer in microchannels or microelectromechanical systems. In addition, various graphs are presented showing simultaneous effects of electric field and wall injection of the same fluid on the flow physics.
Quadratic regression analysis of the unsteady Ag+TiO2/H2O, Ag+TiO2/CH3OH and Ag+TiO2/H2O‐C2H6O2 hybrid nano‐fluids flow along a deformable cylinder with oblique Lorentz force: A comparative approach
Authors: Nandi Susmay , Nadeem Sohail
Published: December 2022

Quadratic regression analysis on the stagnation point flow of Ag+TiO2/H2O, Ag+TiO2/CH3OH and Ag+TiO2/H2O‐C2H6O2 hybrid nano‐fluids past a stretching cylinder placed in a porous medium with multiple slips has been explored numerically. The flow regulating boundary layer equations consider the inclined Lorentz force, viscous‐Ohmic dissipation, heat source, nonlinear way varying thermal radiation, and first‐order chemical reaction. The continuity, energy, and concentration governing equations of tiny‐particles are transformed into a set of ordinary differential equations using the appropriate transformations. The Runge‐Kutta‐Fehlberg method and the well‐known shooting methodology were used to illuminate the numerical for the nonlinear differential equations with the associated boundary conditions. The impact of various controlling factors on velocity, temperature, tiny‐particle concentration, surface drag coefficient, heat transfer rate, and mass transfer rate is then illustrated using numerical analysis. In the absence of a velocity ratio parameter, the hybrid nano‐fluid moves more quickly than when it is present. The temperature and concentration fields, however, show the opposite pattern. Additionally, the temperature profile is highlighted, while the velocity profile fell as the magnetic parameter increased. Moreover, velocity slip reduces the fluid velocity profile, whereas the temperature profile declines for growing values of the temperature jump parameter. The proposed model is useful because it may be used in a variety of fields, such as biomedical sciences, glassblowing, cancer therapies, metal spinning, microelectronics, filament cooling, industrial production processes, biology, etc. Quadratic regression has been statistically used to analyze the effects of pertinent parameters on the drag coefficient and heat and mass transfer rates.
Positivity bounds in vector theories
Authors: de Rham Claudia , Engelbrecht Laura , Heisenberg Lavinia , Lüscher Alice
Published: December 2022

Abstract

Assuming unitarity, locality, causality, and Lorentz invariance of the, otherwise unknown, UV completion, we derive a new set of constraints on the effective field theory coefficients for the most general, ghost-free Generalized Proca and Proca Nuevo massive vector models. For the Generalized Proca model, we include new interactions that had not been previously considered in the context of positivity bounds and find these additional terms lead to a widened parameter space for the previously considered interactions. Although, the Generalized Proca and Proca Nuevo models are inequivalent, we find interesting analogues between the coefficients parameterizing the two models and the roles they play in the positivity bounds.
Determining the spin of light primordial black holes with Hawking radiation
Authors: Calzà Marco , Rosa João G.
Published: December 2022

Abstract

We propose a method to determine the mass and spin of primordial black holes (PBHs) in the mass range 5 × 107–1012 kg (Hawking temperatures ~ 10 MeV–200 GeV), based on measuring the energy of specific features in the photon Hawking emission spectrum, including both primary and secondary components. This is motivated by scenarios where PBHs in this mass range spin up as they evaporate, namely the string axiverse, where dimensionless spin parameters $$ \overset{\sim }{a} $$

a
~

~ 0.1–0.5 can be achieved through the Hawking emission of hundreds or even thousands of light axion-like particles. Measuring the present PBH mass-spin distribution may thus be an important probe of physics beyond the Standard Model. Since the proposed method relies on the energy of the photons emitted by a given PBH, rather than on the associated flux, it is independent of the PBH-Earth distance and, as a byproduct, can also be used to infer the latter.
An Index Theorem for Quarter-Plane Toeplitz Operators via Extended Symbols and Gapped Invariants Related to Corner States
Authors: Hayashi Shin
Published: December 2022

In this paper, we discuss index theory for Toeplitz operators on a discrete quarter-plane of two-variable rational matrix function symbols. By using Gohberg–Kreĭn theory for matrix factorizations, we extend the symbols defined originally on a two-dimensional torus to some three-dimensional sphere and derive a formula to express their Fredholm indices through extended symbols. Variants for families of (self-adjoint) Fredholm quarter-plane Toeplitz operators and those preserving real structures are also included. For some bulk-edge gapped single-particle Hamiltonians of finite hopping range on a discrete lattice with a codimension-two right angle corner, topological invariants related to corner states are provided through extensions of bulk Hamiltonians.
Long-range seed dispersal enables almost stationary patterns in a model for dryland vegetation
Authors: Eigentler L. , Sherratt J. A.
Published: December 2022

Spatiotemporal patterns of vegetation are a ubiquitous feature of semi-arid ecosystems. On sloped terrain, vegetation patterns occur as stripes perpendicular to the contours. Field studies report contrasting long-term dynamics between different observation sites; some observe slow uphill migration of vegetation bands while some report stationary patterns. In this paper, we show that long-range seed dispersal provides a mechanism that enables the occurrence of both migrating and stationary patterns. We utilise a nonlocal PDE model in which seed dispersal is accounted for by a convolution term. The model represents vegetation patterns as periodic travelling waves and numerical continuation shows that both migrating and almost stationary patterns are stable if seed dispersal distances are sufficiently large. We use a perturbation theory approach to obtain analytical confirmation of the existence of almost stationary patterned solutions and provide a biological interpretation of the phenomenon.
Preparation, characterization and magnetic properties of Sm0.95Ho0.05FeO3 nanoparticles and their application in the purification of water
Authors: Arman M. M.
Published: December 2022

Sm0.95Ho0.05FeO3 was successfully prepared in a single phase using the citrate combustion method. The investigated sample was characterized using X-ray diffraction (XRD), a high-resolution transmission electron microscope (HRTEM) and X-ray photoemission spectroscopy (XPS). XRD confirmed that the sample was synthesized in an orthorhombic phase with an average crystallite size of 12 nm. HRTEM indicated that the sample was prepared in the nanoscale with an average particle size of 18 nm. XPS was used to identify the chemical bonds, binding energies and core levels of Sm0.95Ho0.05FeO3. The magnetic properties were studied using a vibrating sample magnetometer and DC magnetic susceptibility using Faraday’s method. The sample has an antiferromagnetic behavior with weak ferromagnetic components. The presence of magnetic Ho3+ ions in the SmFeO3 sample causes the magnetic exchange interaction between the 2p orbital of Fe3+ and the 4d sub-shell of Ho3+ ions. The dependence of pH value on the removal efficiency of Pb2+ from water was studied. The maximum Pb2+ removal efficiency of the Ho-doped SmFeO3 nano perovskite is 26% at pH = 5 and 99% at pH = 8. The Freundlich, Langmuir and Temkin isotherms were studied to understand the adsorption mechanism. The Temkin adsorption isotherm best fitted with the experimental data.
Nozzle geometry effects on supersonic wind tunnel studies of shock–boundary-layer interactions
Authors: Sabnis Kshitij , Galbraith Daniel S. , Babinsky Holger , Benek John A.
Published: December 2022

Many supersonic wind tunnel experiments investigate shock–boundary-layer interactions by measuring the response of tunnel wall boundary layers to an incident shock wave. To generate the supersonic flow, these facilities typically use two-dimensional contoured converging–diverging nozzles which can be arranged in two different ways. One configuration is symmetric about the centre height, whereas this symmetry plane defines the tunnel floor in the other asymmetric arrangement. In order to determine whether these nozzle configurations, which are widely thought to be equivalent, can influence experiments on shock–boundary-layer interactions, two different nozzle geometries are compared with one another in a single facility with rectangular cross section. For each setup, a full-span 8-degree wedge introduces an oblique shock to a Mach 2.5 flow. The two setups exhibit quite dissimilar behaviour, both in the corner regions and on the tunnel’s centre span, with a difference in central separation length of as much as 35% suggesting that nozzle geometry can have a profound impact on these interactions. The observed behaviour is caused by known secondary flows in the sidewall boundary layers which are driven by vertical pressure gradients in the nozzle region. The subsequent impact on the response of the floor boundary layer is consistent with expectations based on local flow momentum affecting corner separation size and on the displacement effect of this corner separation influencing the wider flow.

Graphical abstract
Delayed occurrence of traumatic aortic dissection? Biomechanical considerations and literature
Authors: Muggenthaler H. , Bismann D. , Eckardt N. , Gassler N. , Hubig M. , Subramaniam J. Shanmugam , Mall G.
Published: December 2022

Chronic aortic dissections and pseudoaneurysms caused by chest trauma are rare and generally have to be critically distinguished from non-traumatic dissections and aneurysms. We present a well-documented case of a post-traumatic aortic dissection that ruptured about 9 months after chest trauma. A motorcyclist sustained fractures of the forearm and chest trauma with paravertebral rib serial fractures and hemopneumothorax. Nine months after the accident, echocardiography revealed a pseudoaneurysm that ruptured 3 months later and 1 month prior to the planned surgery. An autopsy showed pericardial tamponade following a rupture of the dissected aorta. Accident scene documentation was consistent with a head-on collision of the motorcycle against the left front side of the car. The relative speed was about 55 km/h. Aggravation of unspecific symptoms after discharge, initial CT imaging, and the absence of atherosclerosis or medial necrosis hold for a post-traumatic genesis of the dissection in our case. Initially, the accident insurance company rejected the regulation. In the second instance, they revised rejection based on our interdisciplinary expert opinion.
Identification and validation of a novel four-gene diagnostic model for neonatal early-onset sepsis with bacterial infection
Authors: Bai Yong , Zhao Na , Zhang Zhenhua , Jia Yangjie , Zhang Genhao , Dong Geng
Published: December 2022

Neonatal early-onset sepsis (EOS) has unfortunately been the third leading cause of neonatal death worldwide. The current study is aimed at discovering reliable biomarkers for the diagnosis of neonatal EOS through transcriptomic analysis of publicly available datasets. Whole blood mRNA expression profiling of neonatal EOS patients in the GSE25504 dataset was downloaded and analyzed. The binomial LASSO model was constructed to select genes that most accurately predicted neonatal EOS. Then, ROC curves were generated to assess the performance of the predictive features in differentiating between neonatal EOS and normal infants. Finally, the miRNA-mRNA network was established to explore the potential biological mechanisms of genes within the model. Four genes (CST7, CD3G, CD247, and ANKRD22) were identified that most accurately predicted neonatal EOS and were subsequently used to construct a diagnostic model. ROC analysis revealed that this diagnostic model performed well in differentiating between neonatal EOS and normal infants in both the GSE25504 dataset and our clinical cohort. Finally, the miRNA-mRNA network consisting of the four genes and potential target miRNAs was constructed. Through bioinformatics analysis, a diagnostic four-gene model that can accurately distinguish neonatal EOS in newborns with bacterial infection was constructed, which can be used as an auxiliary test for diagnosing neonatal EOS with bacterial infection in the future.

Conclusion: In the current study, we analyzed gene expression profiles of neonatal EOS patients from public databases to develop a genetic model for predicting sepsis, which could provide insight into early molecular changes and biological mechanisms of neonatal EOS.

What is Known:• Infants with suspected EOS usually receive empiric antibiotic therapy directly after birth.• When blood cultures are negative after 48 to 72 hours, empirical antibiotic treatment is often halted. Needless to say, this is not a short time. Additionally, because of the concern for inadequate clinical sepsis production and the limited sensitivity of blood cultures, the duration of antibiotic therapy for the kid is typically extended.

What is New:• We established a 4-gene diagnostic model of neonatal EOS with bacterial infection by bioinformatics analysis method. The model has better diagnostic performance compared with conventional inflammatory indicators such as CRP, Hb, NEU%, and PCT.