bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving pedicle screw path planning by vertebral posture estimation
Authors: Zhang Yunxian , Liu Wenhai , Zhao Jingwei , Wang Dan , Peng Fan , Cui Shangqi , Wang Binbin , Shi Zhe , Liu Bo , He Da , Yang Zhi
Published: July 2023

Objective. Robot-assisted pedicle screw placement in spinal surgery can reduce the complications associated with the screw placement and reduce the hospital return counts due to malfunctions. However, it requires accurate planning for a high-quality procedure. The state-of-the-art technologies reported in the literature either ignore the anatomical variations across vertebrae or require substantial human interactions. We present an improved approach that achieves pedicle screw path planning through multiple projections of a numerically re-oriented vertebra with the estimated posture. Approach. We proposed an improved YOLO-type neural network model (YOLOPOSE3D) to estimate the posture of a vertebra before pedicle path planning. In YOLOPOSE3D, the vertebral posture is given as a rotation quaternion and 3D location coordinates by optimizing the intersection over union of the vertebra with the predicted posture and the actual posture. Then, a new local coordinate system is established for the vertebra based on the estimated posture. Finally, the optimal pedicle screw path trajectory is determined from the multiple projections of the vertebra in the local coordinates. Main results. The experimental results in difficult cases of scoliosis showed that the new YOLOPOSE3D network could accurately detect the location and posture of the vertebra with average translation and orientation errors as small as 1.55 mm and 2.55°. The screw path planning achieved 83.1% success rate without breaking the pedicle cortex for the lumbar vertebral L1–L5, which is better than that of a doctor’s manual planning, 82.4%. With the clinical class A requirement to allow less than 2 mm out of the pedicle cortex, the success rate achieved nearly 100%. Significance. The proposed YOLOPOSED3D method can accurately determine the vertebral postures. With the improved posture prior, better clinical outcomes can be achieved for pedicle screw placement in spine internal fixation procedures.
Remote infrared view of JET divertor compatible with D-T operations
Authors: Balboa I , Rose E , Matthews G F , Croft D , Stamp M F , Silburn S A , Williams J C , Hepple D , Huber A , Whetham S , Iglesias D , Kinna D J , Beldishevski M , Figueiredo J , Perez Von Thun C , Balshaw N , Horton L D , Lobel R C , Pearson I J , Pepperell K W , Fishpool G , Lane B , Zastrow K-D , Arnoux G , Bodnar G , Carman P , Carvalho P , Conway N J , Huber V , Karhunen J , Kocsis G , Manzanares A , Puglia P , Ruíz de Galarreta C , Marren C , Otín R , Naish J , Thompson V K
Published: July 2023

A remote viewing system located outside the biological shield wall to image the divertor region in JET is presented here. This paper focuses on the optical and mechanical designs of the installation of a line of sight which is capable of imaging the divertor over an optical distance of approximately 31 m. In addition, it includes the experience obtained during operations and it demonstrates its successful performance. This line of sight was the second viewing system used during the D-T campaign and it follows from the paper dedicated to the remote wide angle view line of sight which is also compatible with D-T operations and includes common elements to the construction of the two lines of sight. The main novel feature is the design in house of two glass reinforced plastic kinematic mounts standing vertically to each accommodate a mirror of 500 mm in diameter.
Simulation of shell pellet injection strategies for ITER-scale tokamaks
Authors: Izzo V A
Published: July 2023

Dispersive shell pellet (DSP) injection is considered as an alternative to shattered pellet injection as a disruption mitigation system for ITER, and strategies for penetration of a shell pellet into ITER are modeled with the 3D magneto-hydrodynamic (MHD) code NIMROD. Because the high plasma temperatures lead to rapid ablation of the shell, delivery of the dispersive payload to the core of ITER will be very challenging. Two strategies to increase payload delivery depth are modeled: first, multiple staggered pellets are simulated in DIII-D, to assess the ability for one DSP to ‘piggy-back’ on another to reach deeper into the core; second, DSP injection after pre-dilution-cooling with deuterium is simulated in ITER, in order to reduce the plasma temperature before shell pellet arrival. The DIII-D simulations show that a second, slower pellet can penetrate much deeper once the release of the first payload strongly cools the mid-radius region. When the pellets are staggered, deeper penetration of the second pellet leads to higher radiation fraction and larger runaway electron loss fraction, consistent with single pellet results. However, simultaneously released pellets at mid-radius that do not trigger a large n = 1 mode produce an even higher radiation fraction. The ITER simulations show that an inside-out TQ can be produced with a payload release just inside of the q = 2 surface, which is achieved at a speed of 800 m s−1 after pre-dilution cooling. Although stochastization of the core leads to a complete thermal quench, the edge flux surfaces are surprisingly robust in the ITER simulations, regardless of payload release location. As a result, runaway electron losses would not be expected.
Investigation of conditions necessary for inception of positive corona in air based on differential formulation of photoionization
Authors: Pasko Victor P , Janalizadeh Reza , Jansky Jaroslav
Published: July 2023

Sharp point electrodes generate significant electric field enhancements where electron impact ionization leads to the formation of electron avalanches that are seeded by photoionization. Photoionization of molecular oxygen due to extreme ultraviolet emissions from molecular nitrogen is a fundamental process in the inception of a positive corona in air. In a positive corona system, the avalanche of electrons in the bulk of the discharge volume is initiated by a specific distribution of photoionization far away from the region of maximum electron density near the electrode where these photons are emitted. Here, we present a new approach to finding the inception conditions for a positive corona, which is based on a differential formulation of the photoionization problem. The proposed iterative solution considers the same inception problem that has been solved in the existing literature by using either an integral approach to photoionization or a differential formulation of photoionization and considering the inception problem as a boundary-value eigenvalue problem. The results are validated by comparisons with previous integral formulations and time dynamic plasma fluid solutions in planar and spherical geometries. The results illustrate ideas advanced in Kaptzov (1950 Elektricheskiye Yavleniya v Gazakh i Vacuume p 610) providing a physically transparent connection between an effective secondary electron emission coefficient due to volume photoionization in a positive corona system and the secondary electron emission in conventional Townsend discharge theory. The results also demonstrate the significance of boundary conditions for accurate corona solutions that are based on a differential formulation of photoionization.
An analytical study of the primordial gravitational-wave-induced contribution to the large-scale structure of the Universe
Authors: Bari Pritha , Bertacca Daniele , Bartolo Nicola , Ricciardone Angelo , Giardiello Serena , Matarrese Sabino
Published: July 2023

The imprint of gravitational waves (GWs) on large-scale structures (LSS) is a useful and promising way to detect or to constrain them. Tensor fossils have been largely studied in the literature as an indirect way to detect primordial GWs. In this paper we analyze a new effect induced by primordial GWs: a correction to the density contrast of the underlying matter distribution of LSS, as well as its radiation counterpart, induced by the energy density fluctuation of the gravitational radiation. We perform our derivation of the full analytical solution of the density contrast for waves entering the horizon during radiation dominance. We account for two phases in the radiation era, depending on the main contributor to the perturbed energy density of the Universe. By comparing the density contrast of cold dark matter and radiation — sourced by linear gravitational waves only — we conclude that the former overcomes the latter at some time in the radiation era, a behaviour analogous to their linear counterpart. Then we conclude by discussing the case of density perturbations produced by GWs entering the Hubble radius during the matter era as well as their evolution in the late dark-energy dominated phase.
Blazar boosted dark matter — direct detection constraints on σeχ
: role of energy dependent cross sections
Authors: Bhowmick Supritha , Ghosh Diptimoy , Sachdeva Divya
Published: July 2023

Elastic collisions with relativistic electrons from the blazar's jet can accelerate dark matter (DM) particles in the DM spike surrounding the supermassive black hole at its center. This can allow one to set stringent limits on the DM-electron scattering cross section (σ̅eχ
) for DM masses less than 100 MeV. We consider DM particles boosted by energetic electrons in the jets of the blazars TXS 0506+056 and BL Lacertae. Both vector and scalar mediators for the scattering of electron and electrophilic fermionic DM are studied. We highlight that the ensuing energy dependence of the S-matrix for the corresponding Lorentz structure of the vertex significantly modifies the constraints. We find that the revised exclusion limits are orders of magnitude stronger than the equivalent results for the simple constant cross section assumption. Our limits are also assessed for the less cuspy spike.
Enhanced germination and electrotactic behaviour of Phytophthora palmivora zoospores in weak electric fields
Authors: Moratto Eleonora , Rothery Stephen , Bozkurt Tolga O , Sena Giovanni
Published: July 2023

Soil-dwelling microorganisms use a variety of chemical and physical signals to navigate their environment. Plant roots produce endogenous electric fields which result in characteristic current profiles. Such electrical signatures are hypothesised to be used by pathogens and symbionts to track and colonise plant roots. The oomycete pathogen Phytophthora palmivora generates motile zoospores which swim towards the positive pole when exposed to an external electric field in vitro. Here, we provide a quantitative characterization of their electrotactic behaviour in 3D. We found that a weak electric field (0.7–1.0 V cm−1) is sufficient to induce an accumulation of zoospore at the positive pole, without affecting their encystment rate. We also show that the same external electric field increases the zoospore germination rate and orients the germ tube’s growth. We conclude that several early stages of the P. palmivora infection cycle are affected by external electric fields. Taken together, our results are compatible with the hypothesis that pathogens use plant endogenous electric fields for host targeting.
Protected simultaneous quantum remote state preparation scheme by weak and reversal measurements in noisy environments
Authors: Manoj Kumar Mandal , S. Choudhury Binayak , Soumen Samanta
Published: July 2023

We discuss a quantum remote state preparation protocol by which two parties, Alice and Candy, prepare a single-qubit and a two-qubit state, respectively, at the site of the receiver Bob. The single-qubit state is known to Alice while the two-qubit state which is a non-maximally entangled Bell state is known to Candy. The three parties are connected through a single entangled state which acts as a quantum channel. We first describe the protocol in the ideal case when the entangled channel under use is in a pure state. After that, we consider the effect of amplitude damping (AD) noise on the quantum channel and describe the protocol executed through the noisy channel. The decrement of the fidelity is shown to occur with the increment in the noise parameter. This is shown by numerical computation in specific examples of the states to be created. Finally, we show that it is possible to maintain the label of fidelity to some extent and hence to decrease the effect of noise by the application of weak and reversal measurements. We also present a scheme for the generation of the five-qubit entangled resource which we require as a quantum channel. The generation scheme is run on the IBMQ platform.
Structure, magnetism and magnetocaloric effects in Er5Si3B
x
(x = 0.3,0.6) compounds
Authors: Hao 郝 Zhihong 志红 , Liu 刘 Hui 辉 , Zhang 张 Juguo 聚国
Published: July 2023

We investigate the structure, magnetic properties, magnetic phase transitions and magnetocaloric effects (MCEs) of Er5Si3B
x
(x = 0.3, 0.6) compounds. The Er5Si3B
x
(x = 0.3, 0.6) compounds crystalize in a Mn5Si3 type hexagonal structure (space group: P63/cm) and exhibit a successive complicated magnetic phase transition. The extensive magnetic phase transitions contribute to the broad temperature range of MCEs exhibiting in Er5Si3B
x
(x = 0.3, 0.6) compounds, with maximum magnetic entropy change (

−
Δ

S
M

max

) and refrigeration capacity of 10.2 J⋅kg−1⋅K−1, 356.3 J/kg and 11.5 J⋅kg−1⋅K−1, 393.3 J/kg under varying magnetic fields 0–5 T, respectively. Remarkably, the δT
FWHM values (the temperature range corresponding to

1
2

×
|
−
Δ

S
M

max

|

) of Er5Si3B
x
(x = 0.3, 0.6) compounds were up to 41.8 K and 39.6 K, respectively. Thus, the present work provides a potential magnetic refrigeration material with a broad temperature range MCEs for applications in cryogenic magnetic refrigerators.
Relating EEG to continuous speech using deep neural networks: a review
Authors: Puffay Corentin , Accou Bernd , Bollens Lies , Monesi Mohammad Jalilpour , Vanthornhout Jonas , Van hamme Hugo , Francart Tom
Published: July 2023

Objective.When a person listens to continuous speech, a corresponding response is elicited in the brain and can be recorded using electroencephalography (EEG). Linear models are presently used to relate the EEG recording to the corresponding speech signal. The ability of linear models to find a mapping between these two signals is used as a measure of neural tracking of speech. Such models are limited as they assume linearity in the EEG-speech relationship, which omits the nonlinear dynamics of the brain. As an alternative, deep learning models have recently been used to relate EEG to continuous speech.Approach.This paper reviews and comments on deep-learning-based studies that relate EEG to continuous speech in single- or multiple-speakers paradigms. We point out recurrent methodological pitfalls and the need for a standard benchmark of model analysis.Main results.We gathered 29 studies. The main methodological issues we found are biased cross-validations, data leakage leading to over-fitted models, or disproportionate data size compared to the model’s complexity. In addition, we address requirements for a standard benchmark model analysis, such as public datasets, common evaluation metrics, and good practices for the match-mismatch task.Significance.We present a review paper summarizing the main deep-learning-based studies that relate EEG to speech while addressing methodological pitfalls and important considerations for this newly expanding field. Our study is particularly relevant given the growing application of deep learning in EEG-speech decoding.
Electrostatic spraying preparation of Si/NiF2/PVDF energetic composites and their reaction characteristics
Authors: Mao Huiqing , Cui Rui , Zhang Xiandie , Ji Jie , Zhou Xiang
Published: July 2023

Metastable intermolecular composites are widely used in energy-demanding fields, where metal fluorides/fluoropolymers as oxidants have been a hot research topic in recent years. In this study, Si/NiF2/PVDF ternary energetic composites were prepared by the electrostatic spraying method for the first time, where NiF2 functions as the oxidant. At the same time, PVDF serves as both the oxidant and the binder. The energetic characteristics of the samples were studied through thermal analysis and preliminary ignition and combustion tests. It is found that the prepared samples are generally in the form of microspheres, in which PVDF binds Si and NiF2 particles together. The addition of Si nanopowder can promote the early decomposition of NiF2, which can improve reactivity. Compared with a physically mixed counterpart, the exothermic reaction between Si and PVDF in microspheres starts at lower temperatures and proceeds to more completion. The electrostatically sprayed sample also shows a shorter combustion time and a more intense luminescence phenomenon.
Study on the influence of mildew on the structure and composition of polycarboxylic acid superplasticizer
Authors: Lin Zhiqun
Published: July 2023

In hot weather, the compounded polycarboxylic acid water reducer often appears mildew and corrupt. This paper will discuss the influence of microorganisms on the structure, composition, and performance of polycarboxylic acid water reducer and its possible reasons through the infrared spectrum, gel chromatography, cement paste fluidity and other experimental tests. The research shows that mildew has no obvious effect on the structure of polycarboxylic acid water reducer, but it will consume the retarder components and produce acids and other metabolites. The initial cement paste fluidity decreases, and the maximum is 10.8%.
Research and application of fast-curing anticorrosion inner coatings for vessels in an acid environment
Authors: Ding Chao , Lin Zhu , Li Yajun , Fang Yan , Tan Chuanjiang , Wang Chiyu , Lou Liangjie , Liu Nan , Mao Zhongqiang , Feng Jinsong
Published: July 2023

According to the anticorrosion demand of petrochemical pressure vessel storing acid medium, phenolic epoxy resin and modified amine curing agent was used, and a tertiary amine curing accelerator was added, a fast-curing acid-resistant anticorrosive coating with excellent acid-resistance was developed by adding the appropriate amount of flake pigments and fillers such as graphene and chemical additives. Through Performance Tests and field application, the coating has high adhesion, good resistance to acid media such as CO2 and H2S, fast curing speed, and the curing time can be shortened from 7 days to 4 days at room temperature, the number of construction tracks is reduced from 4 to 2, which is suitable for on-site anticorrosion maintenance of oil field and chemical pressure vessel and storage tank. It can shorten the construction period and improve the construction efficiency and the anticorrosion quality; extending the service life of the anticorrosive coating has a good prospect of popularization and application.
Hydrothermal preparation of cubic sodium zirconium phosphate crystals
Authors: Wang Yubo , Bai Jiajia , Zuo Juan , Peng Hailong , Hou Haotian , Wang Haoyue , Lan Ning
Published: July 2023

NASICON type material NaZr2(PO4)3 is considered to be the ideal solid electrolyte choice for solid-state Na batteries due to its excellent low thermal expansion and Na ion conductivity. However, the often-prepared solid-state reaction method requires a high reaction temperature and produces other polymerized phosphates and environmentally unfriendly substances. This paper’s hydrothermal method quickly prepared NaZr2(PO4)3 crystals with cubic morphologies at a low temperature. The effects of different concentrations of NaH2PO4 solution and different hydrothermal times on the preparation of the powders were explored. XRD, SEM, TEM and IR tests characterized the as-prepared samples. The results show that the NaZr2(PO4)3 crystals synthesized by the hydrothermal method have good crystallinity and a clean surface, with a standard cubic morphology and a size distribution between 400 nm and 750 nm. This indicates that the hydrothermal method is an effective synthesis one.
Study on Preparation and Properties of Bisphenol S Polycarbonate
Authors: Liu Bin , E Yongsheng
Published: July 2023

Bisphenol S replaces bisphenol A to synthesize bisphenol S polycarbonate, which introduces the sulfone group in polycarbonate, improves the heat resistance and flame resistance of polycarbonate, and expands its application field. In this experiment, bisphenol S reacts with triphosgene to synthesize bisphenol S polycarbonate by interface polycondensation method. The effects of various factors on the product’s molecular weight are investigated and the optimal conditions of reaction are obtained. Through the infrared absorption spectrum, we verify the product structure. Through the Ubbelohde viscometer, the maximum viscosimeter molecular weight is measured and calculated to be 18500. Through the dilatometer, we detect the product’s temperature of glass transition at 166.5°C, which indicates that bisphenol S polycarbonate has good heat resistance. The limiting oxygen index of the product is 33.5%, and the combustion performance level reaches V-0, which indicates that bisphenol S polycarbonate has good flame retardancy.
Effect of Laser Surface Texturing on the Service Performance of Polyetheretherketone
Authors: Sang Shunheng , Wei Wei , Wang Xiaohui , Qiao Yang
Published: July 2023

Polyetheretherketone (PEEK) is an aromatic, semi-crystalline thermoplastic polymer with good wear resistance, corrosion resistance, superior mechanical properties, chemical stability and biocompatibility. While the elastic modulus of PEEK is highly similar to that of cortical bone, based on the many such excellent material properties of PEEK, it is determined that it is often used in intervertebral fusion, artificial joint replacement and trauma implants, etc. Biomedical fields. However, the biological inertness and hydrophobicity of PEEK make it difficult to form osseointegration with human bone, thus limiting its use as a bone repair material. In order to make PEEK better used in the human bone implant field, obtaining PEEK bone implants with excellent biological properties has become the focus of many scholars’ research. In this study, the PEEK surface was laser textured to produce a regular shape, which resulted in a laser-modified PEEK material with better properties. The purpose of this study is to improve the micro-abrasion and wetting properties of PEEK and to enhance the service performance of PEEK materials.
The Research on Characteristics of SAC305/Sn-37Pb/ENIG Solder Joint
Authors: Wang Yanqing , Jiang Qinglei , Feng Mingxiang , Li Xinxin
Published: July 2023

The reliability of the mix alloy of lead and lead-free components with SnPb paste is an important issue for military electronics. With the increase of density in PCB assembly, the traditional HASL pad has been gradually replaced by the ENIG pad for its better flatness and solderability. But the relationship between the interfacial morphology, microstructure and reliability of the alloy of lead and lead-free components still needs to be further studied. In this paper, the microstructure on the interface of SAC305/ Sn-37Pb/ ENIG solder joint is compared with that of typical SAC305/ Sn-37Pb3/ Cu solder joint, Sn63Pb37 / ENIG solder joint. It is found that the IMC layer on the interface of SAC305/Sn-37Pb/ENIG solder joint is more closer to compound (Cu, Ni) 6Sn5, and limited reflow soldering times has little effect on the strength of SAC305/Sn-37Pb/ENIG solder joint. Based on the case study, the thickness of gold layers has a significant effect on black pad problem in ENIG pad.
Research on Sensitive Fluorescence Detection of Fe3+ and Cr2O7
2- in River Based on Ln-MOF Materials
Authors: Wang Runnan , Zhang Hao , Wang Sibo , Meng Fanxu , Sun Jing , Lou Dawei , Su Zhongmin
Published: July 2023

Excessive release of Fe3+ and Cr2O7
2- would threaten public health and environmental safety. Seeking an effective probe for Fe3+ and Cr2O7
2- sensing by a simple and rapid approach in real water samples is significantly desirable. Herein, Eu-MOF for monitoring Fe3+ and Cr2O7
2- were obtained and characterized by PXRD, FT-IR spectroscopy and luminescence spectroscopy. The study showed that Eu-TDA exhibited high sensitivity, special selectivity, and strong stability for Fe3+ and Cr2O7
2- detection. The limit of detection for Fe3+ and Cr2O7
2- were as low as 2.43×10-6 and 3.26×10-6 M, respectively. The fluorescent detection method was used for actual water samples from Songhua River, which obtained satisfied recovery from 98.84% to 106.22%.
Simulation Research on Variable Parameter Drilling of Glass Fiber Reinforced Composite / Copper Foil Laminates
Authors: Shi Hongyan , Zhou Qian , Wang Zhaoguo , Chen Zhuangpei , Zhu Tao
Published: July 2023

Micro-holes play an important role in interconnecting different signal layers of printed circuit boards(PCBs), and their surface quality is critical to signal transmission performance. As an important parameter, drilling force affecting the quality of micro-holes, but its distribution is difficult to obtain because the size of micro-holes is tiny and the drilling process is usually in a semi-closed state. Therefore, simulation of the micro-hole drilling process is studied by Abaqus in this paper. The material of printed circuit board can be regarded as laminated material composed of glass fiber composite and copper foil. The whole simulation process is the simulation of alternating drilling of the two materials. Via simulation, the influence of different drill parameters and processing parameters on the output drilling stress, axial force and drilling quality is obtained, and the results are consistent with the experimental results in the literature. This simulation method can be used as a supplement to the experiment and can provide guidance for the drilling process of printed circuit boards.
Fiber optic detection method for intrinsic defects in carbon fiber composite core overhead conductors considering bending performance
Authors: Wang Yixin , Jia Boyan , Wu Guoqiang , Liu Hongliang , Yi Xiaoyu , Liu Jie
Published: July 2023

Carbon fiber composite core wire in the carbon fiber core rod bending strength is low, easy to break, and thus affects the detection effect. In this regard, it is proposed to consider the bending performance of carbon fiber composite core overhead wire intrinsic defects fiber detection method. The overhead wire is X-ray scanned, and the image is bent compensated by the filtering algorithm. The image is reconstructed using an iterative reconstruction algorithm, and the Tamura texture feature operator is used to extract the roughness feature parameters in the texture feature enhancement map of each conductor to achieve the identification of defects. In the experiments, the proposed method is verified for detection accuracy. The analysis of the experimental results shows that the proposed method has a high correct defect recognition rate and has a more excellent detection accuracy when the proposed method is used to detect the inherent defects of overhead conductors.
The development and application of Silicone-based heat transfer fluids
Authors: Si Rong , Jing Dong , Liu Feng , Kong Dexin , Liu Xiaodi , Lu Jialin
Published: July 2023

The main component of Silicone-based heat transfer fluids is modified silicone oil. The high and low using temperature of silicone-based heat transfer fluids is better than hydrocarbon organic heat transfer fluids. The raising of the maximum using temperature means that it can obtain higher temperature steam in the heat transfer process of the system, and the power generation efficiency of the turbine will be improved remarkably if the silicone-based heat transfer fluids are used in parabolic through the solar power system. It can also increase the efficiency of a solar thermal power plant, so silicone-based heat transfer fluids will be the new type of heat transfer medium. The paper compares these two mediums in terms of structure, composition, and deterioration and introduces the using performance and synthesis method of Silicone. The status of Silicone and problems of application are also presented.
Mineralogical Characteristics and Refractory Properties of Arsenic-bearing Gold Concentrate
Authors: Li Jiafeng , Yang Hongying , Tong Linlin , Chen Qiao
Published: July 2023

The arsenic-bearing gold ore in Anhui, China is an extremely refractory gold ore, and the cyanide leaching rate of gold concentrate is only 30%. The mineralogical factors of the low leaching rate were discussed by process mineralogical analysis. The results demonstrate that the gold concentrate contains 20.30 g/t gold, 3.39% arsenic, 29.80% sulfur, and 4.10% iron. Gold exists in the occurrence states of metallic mineral-wrapped gold, gangue mineral-wrapped gold, and fissure gold, which account for 64.90%, 8.31%, and 26.79% respectively. Pyrite, arsenopyrite, realgar, sphalerite, and pyrrhotite are the main metallic minerals in the gold concentrate. Among them, pyrite accounts for 51.20%, and arsenopyrite accounts for 24.30%. Gangue minerals include feldspar, sericite, quartz, calcite, and chlorite. Among them, feldspar, sericite, and quartz account for 30.30%, 22.70%, and 22.10% respectively. In addition, the grain size distribution and distribution characteristics of various minerals are obtained, and the texture and structure of the gold ore are analyzed. Pyrite and arsenic phase are the main factors causing the low gold leaching rate. The presence of carbonate minerals and clay minerals also has an effect on the rate of gold leaching. The oxidation pretreatment can increase the gold leaching rate to about 94%. The findings provide a theoretical foundation for the selection of manufacturing techniques in businesses and play an important guiding role in the development of similar ores.
Tribological Behaviour of 3D printed Polylactic Acid (PLA) Sliding Against Steel at Different Sliding Speed
Authors: Palaniandy L , Ismail K I , Yap T C
Published: July 2023

In this study, the tribological properties of fused deposition modelling (FDM) 3D printed Polylactic Acid (PLA) is studied when it slides against a steel disk at various speeds. 3D printed pins were printed using PRUSA MINI+ 3D Printer according to recommended printing parameters. Pin on disc tribological tests were conducted at normal load of 20 N, sliding time of 20 minutes, and linear sliding speeds of 0.46, 0.58, 0.7 and 0.81 m/s. Experiment results showed that wear rate increases with the increase of sliding speed, and coefficient of friction decreases with the increase in sliding speed. Observation of worn surfaces suggested the major wear mechanisms are abrasion, adhesion, and delamination. The difference in tribological behaviour was mainly caused by hardness-temperature relationship. The main anomaly that occurred in the observed trends are that the pin melted at highest sliding speed, resulting in opposite trends. The increase in temperature at the contact point of the pin and sliding disk weakens PLA pins. Therefore, 3D printed PLA can be used in a temperature-controlled low speed sliding application such as a lubricated gear and not for applications that subjected to high sliding speeds and temperature.
Numerical Simulation of a Prefabricated Stair Mold Under Fluid Pressure
Authors: Meng Ling-hui
Published: July 2023

In order to realize the large-scale and factory production and transportation of stairs in prefabricated buildings, this paper proposes a prefabricated stair mold, and uses midas Gen to conduct finite element analysis on the stair mold, and obtains the force size of concrete in the form of fluid on the stair mold after pouring. Thus, the displacement contour, stress and local and global deformation rules of each plate of the stair mold are obtained.
Optimization of the Extraction System of Total Phenolic from Garcia mangostana using Response Surface Methodology
Authors: Chung Tsair-Wang , Kurniawan Irwan Saleh
Published: July 2023

Mangosteen (Garcia mangostana) consist of 40% flesh and 60% pericarp. Mangosteen pericarp has unpleasant taste of bitterness and usually disposed as waste. However, mangosteen pericarp contains xanthones which are polyphenolic compound that proven has high antioxidant activity were found abundantly in mangosteen pericarp. This study aims to investigate water extraction optimum operating conditions to be applied in industry by using RAM (response surface methodology) for the recovery of total phenolic extract from the pericarp of mangosteen. Box-Behnken experimental design used 3 factors. Solid-to-liquid ratio (g/ml), temperature (°C) and extraction time (hour) were analysed to compare the response of total phenolic content (TPC). Under the operating conditions, the highest TPC is 0.906 (g/l) at the factors of 1:10 (g/ml), 65 °C, and 3-hour. The optimum parameters determined by using RSM are at 1:10 (g/ml), 59.74 °C, and 2.87-hour with TPC 0.835 (g/l).
Research on Virtual Reality Head-Mounted Displays based on MEMS Technology
Authors: Ren Zhongju , Dong Keyan , Fu Xiuhua , lai Ying , Zhang Jingjing
Published: July 2023

In order to render the gaze area and increase the pixels per degree of the area, this virtual reality head-mounted display device adds two MEMS 2D miniature scanning mirrors to the main display imaging, with a laser diode as the projection light source and the main display as the projection receiving screen. The light emitted by the laser lamp is projected onto the main display through multiple reflections. Through pre-processing of the image of the main display and the projected display, the image of the main display is combined with the projected image to achieve the rendering effect. It is integrated with an eye tracking system that allows the projected image to be consistently projected on the human eye area. The projection image is projected over the entire imaging area of the main display by resonant rotation of two MEMS 2D microscope mirrors.
Source or sink? Meta-analysis reveals diverging controls of phosphorus retention and release in restored and constructed wetlands
Authors: Ury Emily A , Arrumugam Puvaanah , Herbert Ellen R , Badiou Pascal , Page Bryan , Basu Nandita B
Published: July 2023

Wetland restoration is a popular nutrient management strategy for improving water quality in agricultural catchments. However, a wetland’s ability to retain phosphorus is highly variable and wetlands can sometimes be a source of phosphorus to downstream ecosystems. Here, we used a meta-analysis approach to explore the source and sink capacity of 139 wetlands for both total phosphorus (TP) and the more bioavailable form, phosphate (PO4
3−), at seasonal and annual timescales. Median retention efficiency across all studies is 32% for TP and 28% for PO4
3−, however the range is extremely broad. We found that wetlands are often sinks for TP (84% of site-years) and PO4
3− (75% of site years). The median TP retention within wetlands that are sinks (2.0 g·m−2·yr−1) is greater than release by wetlands that are sources (−0.5 g·m−2·yr−1). In contrast, for PO4
3−, median retention within wetlands that are phosphorus sinks (0.8 g·m−2·yr−1) is of similar magnitude to that released by wetlands that are phosphorus sources (−0.7 g·m−2·yr−1). We found that phosphorus release from wetlands coincides with higher hydraulic loading rates, lower influent phosphorus concentration, and legacy soil/sediment phosphorus. Phosphate releases were especially common in wetlands used for treating municipal wastewater, as well as restored and constructed wetlands with flashy, precipitation-driven flow. We found that experimental design may inherently bias our understanding of wetland performance for phosphorus retention as studies conducted in mesocosms outperform other wetland types. Analysis of monthly data demonstrated significant temporal variability in wetland phosphorus dynamics, often switching from retention to release many times within a year, but with no generalizable seasonal trends. Our results highlight the value of restoring wetlands for phosphorus retention and point to ways of furthering their utility towards improving water quality by simultaneously targeting retention enhancing measures and release avoidance.
On the role of climate change in the 2018 flooding event in Kerala
Authors: Dhasmana Manish Kumar , Mondal Arpita , Zachariah Mariam
Published: July 2023

The extreme precipitation during August 2018 in Kerala, India was catastrophic, triggering one of the worst floods in history. There is growing evidence of human-induced climate change in driving hydroclimatic extremes across the globe. However, whether and to what degree the 2018 flooding event in Kerala was influenced by climate change has yet to be fully understood. To this end, we present the first formal attribution analysis of the event, using the probabilistic event attribution (PEA) framework. Three methods using (i) Historical and HistoricalNat runs from CMIP6 (general circulation models-based method), (ii) observed records from 1901–2018 for two periods, split at 1950 (time-slice method) and (iii) observations that are scaled to 1901 and 2018 climates (scaling method), are considered for quantifying the risk ratio (RR) of the event. Using an objective approach, the 2018 precipitation event is defined by the return period of the 4 day cumulative precipitation over the Periyar River Basin (PRB), during 15–18 August, 2018. The subsequent flood event is characterized by the return period of the 1 day maximum streamflow at one of the outlets of the PRB, where maximum impact during the event was reported. The results from multiple methods are consistent, suggesting that the event is exceptionally less likely to have been caused by anthropogenic climate change, with RR for the precipitation and flood events ranging from 0.31 to 0.82 and 0.55 to 0.8, respectively. The role of wet antecedent soil moisture conditions, which is found to be the primary driving factor of floods in the PRB, is also found to be unchanged between simulations with and without climate change. Our results highlight the challenges in unequivocal discerning of the climate change signal on regional hydrological events and emphasize the importance of better consideration of local confounding interventions in PEA studies.
Complete and orthonormal sets of exponential-type orbitals with non-integer quantum numbers
Authors: Bağcı A , Hoggan P E
Published: July 2023

Atomic and molecular orbitals show exponential decrease at long range. Complete orthonormal basis sets for atoms should satisfy this criterion. A number of such bases have been used in physics (e.g. Coulomb Sturmians). The challenge of this work is first adapting Slater type Orbitals for this role, as they are not radially orthogonal. Even more important is their generalization to non-integer quantum numbers that have applications for configuration interaction. This generalization requires the whole apparatus of non-integer calculus that is presented using the Riemann–Liouville approach.
Physics design of 14 MeV neutron generator facility at the Institute for Plasma Research
Authors: SWAMI H L , VALA S , RAJPUT M , ABHANGI M , KUMAR Ratnesh , SAXENA A , KUMAR Rajesh
Published: July 2023

A high energy and high yield neutron source is a prime requirement for technological studies related to fusion reactor development. It provides a high-energy neutron environment for small-scale fusion reactor components research and testing such as tritium breeding, shielding, plasma-facing materials, reaction cross-section data study for fusion materials, etc. Along with ITER participation, the Institute of Plasma Research, India is developing an accelerator-based 14 MeV neutron source with a yield of 1012 n s−1. The design of the source is based on the deuterium–tritium fusion reaction. The deuterium beam is accelerated and delivered to the tritium target to generate 14 MeV neutrons. The deuterium beam energy and tritium availability in the tritium target are the base parameters of the accelerator-based neutron source design. The paper gives the physics design of the neutron generator facility of the Institute for Plasma Research. It covers the requirements, design basis, and physics parameters of the neutron generator. As per the analytical results generator can produce more than 1 × 1012 n s−1 with a 110 keV D+ ion beam of 10 mA and a minimum 5 Ci tritium target. However, the detailed simulation with the more realistic conditions of deuteron ion interaction with the tritium titanium target shows that the desired results cannot be achieved with 110 keV. The safe limit of the ion energy should be 300 keV as per the simulation. At 300 keV ion energy and 20 mA current, it reaches 1.6 × 1012 n s−1. Moreover, it was found that to ensure sufficiently long operation time a tritium target of more than 20 Ci should be used. The scope of the neutron source is not limited to the fusion reactor research studies, it is extended to other areas such as medical radioisotopes research, semiconductor devices irradiations, and many more.
On the seeds and the great-grandchildren of a numerical semigroup
Authors: Bras-Amorós Maria
Published: July 2023

We present a revisit of the seeds algorithm to explore the semigroup tree. First, an equivalent definition of seed is presented, which seems easier to manage. Second, we determine the seeds of semigroups with at most three left elements. And third, we find the great-grandchildren of any numerical semigroup in terms of its seeds.

The the right-generators descendant (RGD) algorithm is the fastest known algorithm at the moment. But if one compares the originary seeds algorithm with the RGD algorithm, one observes that the seeds algorithm uses more elaborated mathematical tools while the RGD algorithm uses data structures that are better adapted to the final C implementations. For genera up to around one half of the maximum size of native integers, the newly defined seeds algorithm performs significantly better than the RGD algorithm. For future compilators allowing larger native sized integers this may constitute a powerful tool to explore the semigroup tree up to genera never explored before. The new seeds algorithm uses bitwise integer operations, the knowledge of the seeds of semigroups with at most three left elements and of the great-grandchildren of any numerical semigroup, apart from techniques such as parallelization and depth first search as wisely introduced in this context by Fromentin and Hivert [Math. Comp. 85 (2016) pp. 2553–2568].

The algorithm has been used to prove that there are no Eliahou semigroups of genus

66
66

, hence proving the Wilf conjecture for genus up to

66
66

. We also found three Eliahou semigroups of genus

67
67

. One of these semigroups is neither of Eliahou-Fromentin type, nor of Delgado’s type. However, it is a member of a new family suggested by Shalom Eliahou.
𝐿^{∞} estimates for Kähler-Ricci flow on Kähler-Einstein Fano manifolds: A new derivation
Authors: Jian Wangjian , Shi Yalong
Published: July 2023

Assuming Perelman’s estimates, we give a new proof of uniform

L
∞

L^\infty

estimate along normalized Kähler-Ricci flow on Fano manifolds with Kähler-Einstein metrics, using Chen-Cheng’s auxiliary Monge-Ampère equation and the Alexandrov-Bakelman-Pucci maximum principle. This proof does not use pluripotential theory.
Algebraic de Rham theory for the relative completion of 𝑆𝐿₂(ℤ)
Authors: Luo Ma
Published: July 2023

We develop an explicit algebraic de Rham theory for the relative completion of

S
L

2

(

Z

)

{\mathrm {SL}}_2(\mathbb {Z})

. This allows the construction of iterated integrals involving modular forms of the second kind, generalizing iterated integrals of holomorphic modular forms that were previously studied by Brown and Manin. These newly constructed iterated integrals provide all ‘multiple modular values’ defined by Brown.
Complex Systems of Property: Change and Resilience After a Catastrophic Disaster
Authors: Fitzpatrick Daniel
Published: July 2023

This Article applies emerging literature on resilience in complex systems to institutional change in property rights systems. Complex systems theory provides an alternative to economic models that adopt assumptions of linearity in property rights transitions—where inputs such as rising resource values induce proportionate outputs in the formation of private property rights. Based on a case study of catastrophic disaster, the Article concludes that institutional change in a complex property system does not involve proportionate or predictable responses to sudden shocks in the external environment. The stochasticity of institutional change arises from acts of adaptive self-organization across multiple scales of proprietary governance. The “added value” of systems theory is a set of conceptual tools—such as scale, stochasticity, and self-organization—which help to explain resilience and change in property systems affected by sudden environmental shocks.
A scalable approach for continuous time Markov models with covariates
Authors: Hatami Farhad , Ocampo Alex , Graham Gordon , Nichols Thomas E , Ganjgahi Habib
Published: July 2023

Existing methods for fitting continuous time Markov models (CTMM) in the presence of covariates suffer from scalability issues due to high computational cost of matrix exponentials calculated for each observation. In this article, we propose an optimization technique for CTMM which uses a stochastic gradient descent algorithm combined with differentiation of the matrix exponential using a Padé approximation. This approach makes fitting large scale data feasible. We present two methods for computing standard errors, one novel approach using the Padé expansion and the other using power series expansion of the matrix exponential. Through simulations, we find improved performance relative to existing CTMM methods, and we demonstrate the method on the large-scale multiple sclerosis NO.MS data set.
Tildrakizumab for the treatment of hidradenitis suppurativa in patients previously treated with adalimumab: a 30-month experience
Authors: Koszegi Ben , Wilson Anna , Stone Corey , Satgé Fanny , Cowan Timothy L , Murrell Dédée F
Published: July 2023

Our case series findings indicate that tildrakizumab treatment in patients with hidradenitis suppurativa who previously received adalimumab demonstrated an initial improvement in disease activity within the first 6 months. However, this overall trend was not sustained beyond the 6-month mark. Nevertheless, it is noteworthy that patients who underwent long-term follow-up on tildrakizumab experienced ongoing disease activity but showed a reduction in Dermatology Life Quality Index scores.
Temporal fingerprints of cortical gyrification in marmosets and humans
Authors: Wang Qiyu , Zhao Shijie , Liu Tianming , Han Junwei , Liu Cirong
Published: July 2023

Recent neuroimaging studies in humans have reported distinct temporal dynamics of gyri and sulci, which may be associated with putative functions of cortical gyrification. However, the complex folding patterns of the human cortex make it difficult to explain temporal patterns of gyrification. In this study, we used the common marmoset as a simplified model to examine the temporal characteristics and compare them with the complex gyrification of humans. Using a brain-inspired deep neural network, we obtained reliable temporal-frequency fingerprints of gyri and sulci from the awake rs-fMRI data of marmosets and humans. Notably, the temporal fingerprints of one region successfully classified the gyrus/sulcus of another region in both marmosets and humans. Additionally, the temporal-frequency fingerprints were remarkably similar in both species. We then analyzed the resulting fingerprints in several domains and adopted the Wavelet Transform Coherence approach to characterize the gyro-sulcal coupling patterns. In both humans and marmosets, sulci exhibited higher frequency bands than gyri, and the two were temporally coupled within the same range of phase angles. This study supports the notion that gyri and sulci possess unique and evolutionarily conserved features that are consistent across functional areas, and advances our understanding of the functional role of cortical gyrification.