bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing Methods for Estimating Habitat Suitability
Authors: Muhammed Khaleel , Anandhi Aavudai , Chen Gang
Published: October 2022

Habitat suitability (HS) describes the ability of the habitat to support living organisms. There are several approaches to estimate habitat suitability. These approaches are specific to a species or habitat or estimate general HS broadly across multiple species or habitats. The objectives of the study were to compare the approaches for estimating HS and to provide guidelines for choosing an appropriate HS method for conservation. Three HS estimation methods were used. Method 1 scores the suitability based on the naturality of the habitat. Method 2 uses the average of HS values found in the literature. Method 3 uses the species richness as an indicator for HS. The methods were applied to a case study in the Choctawhatchee River Watershed. GIS applications were used to model the suitability of the watershed. The advantages and disadvantages of the HS methods were then summarized. The multiple HS maps created using the three methods display the suitability of the watershed. The highest suitability occurred in the southern parts of the region. Finally, a decision support tool was developed to help determine which approach to select based on the available data and research goals.
Evaluation Method of Composite Development Bus Terminal Using Multi-Source Data Processing
Authors: Zhang Tao , Yan Yibo , Chen Qi , Liu Ze
Published: October 2022

Given the accelerating speed and scale of urbanization in China, a rational formulation of a composite development plan to increase the vitality and value of various areas is required. Thus, this study proposes a method for evaluating the spatial relationship among facilities around bus terminals by combining urban points-of-interest data and street view image data from two perspectives: the current level of development and potential of the terminals, and an evaluation of the surrounding pedestrian environment. This is in response to the lack of quantitative descriptions of the composite development of existing bus terminals. The validity and applicability of the methods are verified using the samples of five planned composite development bus terminals in the city of Zhengzhou. These results offer strategic suggestions for the composite development of the Zhengzhou bus terminals. This study demonstrates innovation in integrating geographic information data and street view image data. It reflects the spatial characteristics of the built environment using geographic information data and the visual characteristics of the built environment using street view images.
Mao Dun’s “Spring Silkworms”: Living Like Worms
Authors: Foley Todd
Published: October 2022

Mao Dun’s (茅盾) 1932 short story “Spring Silkworms” (春蚕), the first of a three-part series known as the Village Trilogy, is widely regarded as one of the author’s most representative works. Given Mao Dun’s leftist politics and commitment to critical realism, the story has generated debate over its depiction of the Chinese peasantry and the extent to which it condemns tradition in support of revolutionary progress. This article contends that the key to the ambiguity of the peasants’ depiction lies in the fundamental questioning of what is human, which underlies the story’s overall ideological framework. Through a close examination of the story and its 1933 film adaptation, the article aims to show how the silkworms act as a metaphor for the villagers themselves, who are dehumanized through their helplessness and alienated labor. By reading the human villagers as metaphorical worms, the article demonstrates how they are both exposed as a kind of valueless “bare life” and situated in a narrative pause in historical materialist time, which indicates a space for the potential fundamental reconceptualization of the human. Ultimately, the article hopes to push beyond didactic readings of the story’s politics to reveal an ontological anxiety at its core.
Risk Prevention and Health Promotion for Non-Alcoholic Fatty Liver Diseases (NAFLD)
Authors: Khan Adnan , Ross Heather M. , Parra Natalia Salinas , Chen Sarah L. , Chauhan Kashyap , Wang Makala , Yan Brian , Magagna John , Beiriger Jake , Shah Yash , Shahzad Taha , Halegoua-DeMarzio Dina
Published: October 2022

Non-alcoholic fatty liver disease (NAFLD) is a serious clinicopathological condition that is recognized as the most frequent chronic liver disease, affecting 14–30% of the world’s population. The prevalence of NAFLD has rapidly grown and is correlated with the growth in obesity and type 2 diabetes, among other factors. NAFLD often results in long-term complications including cardiovascular disease, liver cirrhosis, and liver fibrosis. This paper provides an updated overview of NAFLD with a focus on epidemiology, etiology, pathophysiology, screening, complications, and pharmacological therapies to identify effective risk prevention and health promotion.
Recent Developments in Cassava (Manihot esculenta) Based Biocomposites and Their Potential Industrial Applications: A Comprehensive Review
Authors: Abotbina Walid , Sapuan S. M. , Ilyas R. A. , Sultan M. T. H. , Alkbir M. F. M. , Sulaiman S. , Harussani M. M. , Bayraktar Emin
Published: October 2022

The rapid use of petroleum resources coupled with increased awareness of global environmental problems associated with the use of petroleum-based plastics is a major driving force in the acceptance of natural fibers and biopolymers as green materials. Because of their environmentally friendly and sustainable nature, natural fibers and biopolymers have gained significant attention from scientists and industries. Cassava (Manihot esculenta) is a plant that has various purposes for use. It is the primary source of food in many countries and is also used in the production of biocomposites, biopolymers, and biofibers. Starch from cassava can be plasticized, reinforced with fibers, or blended with other polymers to strengthen their properties. Besides that, it is currently used as a raw material for bioethanol and renewable energy production. This comprehensive review paper explains the latest developments in bioethanol compounds from cassava and gives a detailed report on macro and nano-sized cassava fibers and starch, and their fabrication as blend polymers, biocomposites, and hybrid composites. The review also highlights the potential utilization of cassava fibers and biopolymers for industrial applications such as food, bioenergy, packaging, automotive, and others.
Numerical Investigation of the Performance of Segmental CFST Piers with External Energy Dissipators under Lateral Cyclic Loadings
Authors: Wang Chengquan , Qu Zheng , Shen Yonggang , Jiang Jiqing , Yin Chongli , Zong Yanwei
Published: October 2022

In order to improve the construction efficiency of piers and reduce the local damage of piers, concrete-filled steel tubes (CFST) are used to precast pier segments. Aiming at the problems of the poor integrity and insufficient energy dissipation capacity of dry joint segmental assembled piers, segmental assembled concrete-filled steel tubular piers with external replaceable energy dissipators are being developed. Based on the low cyclic test of a segmental assembled CFST pier, the finite element numerical simulation model of a CFST pier is established based on ABAQUS software, and the validity of the numerical model is verified by the experimental results. The effects of the section ratio, axial compression ratio, and initial prestress on the seismic performance of piers are studied through a pseudostatic analysis. The results show that an increase in the section ratio can improve the lateral bearing capacity and energy dissipation capacity of the pier. When the section ratio is increased to 4%, the energy dissipation capacity of a CFST pier is increased by 77.8% and the lateral bearing capacity is increased by 33.9% compared with a section ratio of 2%, but the residual displacement of the pier top also increases. With an increase in the axial compression ratio, the energy dissipation capacity of the pier is significantly improved; when the axial compression ratio is increased to 0.30, the energy dissipation capacity of CFST piers is increased by 27.5% compared with a section ratio of 0.05, the residual displacement of the pier top is reduced, and the self-resetting effect of the pier is improved. A change in the initial prestress has no effect on the energy dissipation capacity of piers. Finally, based on an analysis of mechanical theory, a formula of bending capacity suitable for this type of pier is proposed, and the error is within 10%.
Research on Bending and Ballistic Performance of Three-Dimensional Ply-to-Ply Angle Interlock Kevlar/EP Armor Material
Authors: Wang Mengxiao , Zhong Lin , Cao Haijian , Chen Hongxia , Huang Xiaomei
Published: October 2022

The three-dimensional (3D) shallow cross-bending composite material has many advantages in thickness and in-plane direction, such as high strength, high modulus, inter-layer shear strength, as well as large-area area bearing, energy absorption, etc., which has great application potential in the field of bulletproof armor. To prepare a protective material with both excellent bending performance and good ballistic performance, the effects of weft density and layering method on the bending performance and ballistic performance of three-dimensional ply-to-ply angle interlock (3DPPAI) Kevlar/EP armor materials were studied. The results showed that when the weft density of the material was 33 pieces/cm, its bending performance and ballistic resistance were the best. The 3DPPAI Kevlar/EP armor material prepared by orthogonal layup had more advantages in bending performance, and the unidirectional layup had better anti-ballistic performance. The research results will lay the foundation for structural optimization and engineering applications of such materials.
Interlayer Shear Characteristics of Bridge Deck Pavement through Experimental and Numerical Analysis
Authors: Chen Weidong , Hui Bing , Rahman Ali
Published: October 2022

In order to study the interlayer shear behavior of bridge deck pavement, a numerical simulation was conducted to analyze the influence of varying interfacial conditions on shear stress at the bottom of pavement layers under the moving loading effect. Moreover, the shear strength of the different adhesive and waterproof adhesive materials was evaluated by conducting laboratory tests. The results showed that improving the bonding condition at the upper interlayer led to the reduction of the shear stress at the bottom of the pavement layers. With the increase of the friction coefficient of the upper interface to the full bonding state, the resulting shear stress at the bottom of the upper layer declined to the lowest value, which was about 35% of that of the full slip state. When the lower interlayer was in the full slip or partial bonding state, the resulting shear stress at the bottom of the lower layer decreased linearly with the increase of the friction coefficient of the upper interlayer. Moreover, once the contact state of the upper interlayer reached the full bonding state, the resulting shear stress at the bottom of the lower layer reached the minimum, which is about 88% of that of the full slip state. To improve the integrity and shear resistance of the bridge deck pavement structure, interlayer bonding should be strengthened. In this regard, the resin emulsified asphalt was determined as an appropriate adhesive material to be applied at the upper and lower interlayers. In addition, interlayer shear bond strength, regardless of the type of adhesive materials, was decreased with increasing temperature. Finally, statistical analysis results indicated that all factors of structure type, type of adhesive material, and temperature statistically have a significant effect on interlayer bond strength. The findings of this study could provide a theoretical basis and experimental support for improving the interlayer design and construction in the concrete bridge deck pavement structure.
Evaluation of the Properties and Microstructure of Thick-Walled Welded Joint of Wear Resistant Materials
Authors: Krawczyk Ryszard , Słania Jacek , Golański Grzegorz , Zieliński Adam
Published: October 2022

The research was conducted on a thick-walled welded joint between the HTK 900H wear-resistant steel plates and the A6 cast profile. The aim of the experiment was to produce a joint with the relevant performance requirements, i.e., a good abrasion resistance joint in the weld face area while ensuring its proper plasticity. The welded joint was made using the MAG PULSE and the high-performance MAG TANDEM methods under automated conditions using the linear welding energy ranging from 1.2 to 2.2 kJ/mm for the different joint regions. The scope of the research included both non-destructive and destructive testing. The non-destructive visual (VT), magnetic-particle (MT), and ultrasonic (UT) tests revealed a good quality of the welded joint with no significant welding imperfections. The microstructure of the welded joint in the weld zone was characterized by a dominant volume fraction of martensite/bainite. The measurement of hardness near the face of the weld confirmed obtaining similar values for this parameter. The HTK 900H steel was characterized by hardness at the level of 383 HV10, whereas the A6 cast-328 HV10, and the weld-276 HV10. At the same time, the analyzed joint showed high ductility in the range of 86 to 159 J. The tests carried out showed that the linear energy control allowed a welded joint with the required performance characteristics to be obtained.
Incorporation of Silica Particles Attached to Nylon 66 Electrospun Nanofibers with Cement
Authors: Nguyen Tri N. M. , Lee Do Hyung , Kim Jung J.
Published: October 2022

In this study, a modified version of electrospun nylon 66 nanofibers by silica particles were blended into ordinary Portland cement to investigate the microstructure and some mechanical properties of cementitious material. The addition of silica into the nanofibers improved the tensile and compressive properties of the hardened cement pastes. The observations from the mechanical strength tests showed an increase of 41%, 33% and 65% in tensile strength, compressive strength, and toughness, respectively, when modifying the cement pastes with the proposed nanofibers. The observations from scanning electron microscopy and transmission electron microscopy showed the morphology and microstructure of the fibers as well as their behaviors inside the cement matrix. Additionally, X-ray diffraction and thermal gravimetric analysis clarified the occurrence of the extra pozzolanic reaction, as well as the calcium hydroxide consumption by the attached silica inside the cement matrix. Finally, the observations from this study showed the successful fabrication of the modified nanofibers and the feasibility of improving the tensile and compressive behaviors of cement pastes using the proposed electrospun nanofibers.
Modeling, Identification, and Compensation Control of Friction for a Novel Dual-Drive Hydrostatic Lead Screw Micro-Feed System
Authors: Liu Yandong , Feng Xianying , Li Peigang , Li Yanfei , Su Zhe , Liu Haiyang , Lu Ziteng , Yao Ming
Published: October 2022

This paper investigates the transmission performance of a novel dual-drive hydrostatic lead screw micro-nano feed system (DDHLS) that can obtain extremely low speed. Firstly, the oil film liquid friction of hydrostatic transmission is modelled, and the calculation model of oil film dynamic friction is proposed based on the variable viscosity theory. Secondly, on this basis, combined with the LuGre friction model, a novel all-components refinement friction identification method (ACRFIM) for DDHLS was developed. The friction parameters of the feed drive components such as LM guide and hydrostatic lead screw can be identified independently using the proposed method, ensuring precise friction force modelling in all components. Then, an all-component adaptive friction compensation control algorithm (AACA) was designed by introducing the temperature and disturbance influence factors into the friction model and considering the influence of the dynamic friction of liquid. The experiments illustrate that the calculation accuracy of the oil film friction model based on the variable viscosity theory is substantially improved. DDHLS can effectively suppress the adverse effects of nonlinear friction, and the proposed AACA has an obvious compensation effect for the friction of the time-varying system.
A Lower Limb Rehabilitation Robot with Rigid-Flexible Characteristics and Multi-Mode Exercises
Authors: Dong Mingjie , Yuan Jianping , Li Jianfeng
Published: October 2022

Lower limb rehabilitation robot (LLRR) can effectively help restore the lower limb’s motor function of patients with hemiplegia caused by stroke through a large number of targeted and repetitive rehabilitation training. To improve the safety and comfort of robot-assisted lower limb rehabilitation, we developed an LLRR with rigid-flexible characteristics; the design of passive joints is used to improve human-machine compatibility; the design of flexible unit makes the mechanism have certain rigid-flexible characteristics. Three different rehabilitation training methods have been developed to adapt to the patients at different stages of rehabilitation, namely, passive exercise, active exercise and resistance exercise, respectively. Experiments with healthy subjects have been conducted to verify the effectiveness of the development of the different training modes of the LLRR, showing good compatibility of the mechanism and good trajectory tracking performance of the developed training methods.
Efficiency and Core Loss Map Estimation with Machine Learning Based Multivariate Polynomial Regression Model
Authors: Mısır Oğuz , Akar Mehmet
Published: October 2022

Efficiency mapping has an important place in examining the maximum efficiency distribution as well as the energy consumption of designed electric motors at maximum torque and speed. Performing analysis at all operating points with FEM analysis in the motor design process requires high processing costs and time. In this article, a machine learning-based multivariate polynomial regression estimation model was developed to overcome these costly processes from FEM analysis. With the proposed method, the operating points of the motors in different conditions during the design process can be predicted in advance with high accuracy. In the study, two different models are developed for efficiency map and core loss estimation of interior permanent magnet synchronous motor design. The developed models use few parameters and predict with high accuracy. Estimation models shorten the design process and offer a less complex model. Obtained results are validated by comparison with FEM analysis.
An Efficient Third-Derivative Hybrid Block Method for the Solution of Second-Order BVPs
Authors: Rufai Mufutau Ajani
Published: October 2022

A new one-step hybrid block method with two-point third derivatives is developed to solve the second-order boundary value problems (BVPs). The mathematical derivation of the proposed method is based on the interpolation and collocation methods. The theoretical properties of the proposed method, such as consistency and convergence, are well analysed. Some BVPs with different boundary conditions are solved to demonstrate the efficiency and feasibility of the suggested method. The numerical results of the proposed method are much closer to the exact solutions and more competitive than other numerical methods in the available literature.
Application of an Adaptive Adjacency Matrix-Based Graph Convolutional Neural Network in Taxi Demand Forecasting
Authors: Xu Jian-You , Zhang Shuo , Wu Chin-Chia , Lin Win-Chin , Yuan Qing-Li
Published: October 2022

Accurate forecasting of taxi demand has facilitated the rational allocation of urban public transport resources, reduced congestion in urban transport networks, and shortened passenger waiting time. However, virtual station discovery and modelling of the demand when forecasting through graph convolutional neural networks remains challenging. In this study, the virtual station discovery problem was addressed by using a two-stage clustering approach, which considers the geographical and load characteristics of taxi demand. Furthermore, a fusion model combining non-negative matrix decomposition and a graph convolutional neural network was proposed in order to extract the features of the nodes for dimension reduction and adaptive adjacency matrix computation. By the construction of a local processing structure, further extraction of the local characteristics of the demand was achieved. The experimental results show that the method in this study outperforms state-of-the-art methods in terms of the root mean square error and average absolute value error. Therefore, the model proposed in this study is able to achieve accurate forecasting of taxi demand.
Optimization Methods for Redundancy Allocation in Hybrid Structure Large Binary Systems
Authors: Cașcaval Petru , Leon Florin
Published: October 2022

This paper addresses the issue of optimal redundancy allocation in hybrid structure large binary systems. Two aspects of optimization are considered: (1) maximizing the reliability of the system under the cost constraint, and (2) obtaining the necessary reliability at a minimum cost. The complex binary system considered in this work is composed of many subsystems with redundant structure. To cover most of the cases encountered in practice, the following kinds of redundancy are considered: active redundancy, passive redundancy, hybrid standby redundancy with a hot or warm reserve and possibly other cold ones, triple modular redundancy (TMR) structure with control facilities and cold spare components, static redundancy: triple modular redundancy or 5-modular redundancy (5MR), TMR/Simplex with cold standby redundancy, and TMR/Duplex with cold standby redundancy. A classic evolutionary algorithm highlights the complexity of this optimization problem. To master the complexity of this problem, two fundamentally different optimization methods are proposed: an improved evolutionary algorithm and a zero-one integer programming formulation. To speed up the search process, a lower bound is determined first. The paper highlights the difficulty of these optimization problems for large systems and, based on numerical results, shows the effectiveness of zero-one integer programming.
Bipartite Synchronization of Fractional-Order Memristor-Based Coupled Delayed Neural Networks with Pinning Control
Authors: Dhivakaran P. Babu , Vinodkumar A. , Vijay S. , Lakshmanan S. , Alzabut J. , El-Nabulsi R. A. , Anukool W.
Published: October 2022

This paper investigates the bipartite synchronization of memristor-based fractional-order coupled delayed neural networks with structurally balanced and unbalanced concepts. The main result is established for the proposed model using pinning control, fractional-order Jensen’s inequality, and the linear matrix inequality. Further, new sufficient conditions are derived using the Lyapunov–Krasovskii functional with delay-dependent criteria. Finally, numerical simulations are provided including two numerical examples to show the effectiveness of the theoretical results.
Printed Texture Guided Color Feature Fusion for Impressionism Style Rendering of Oil Paintings
Authors: Geng Jing , Ma Li’e , Li Xiaoquan , Zhang Xin , Yan Yijun
Published: October 2022

As a major branch of Non-Photorealistic Rendering (NPR), image stylization mainly uses computer algorithms to render a photo into an artistic painting. Recent work has shown that the ex-traction of style information such as stroke texture and color of the target style image is the key to image stylization. Given its stroke texture and color characteristics, a new stroke rendering method is proposed. By fully considering the tonal characteristics and the representative color of the original oil painting, it can fit the tone of the original oil painting image into a stylized image whilst keeping the artist’s creative effect. The experiments have validated the efficacy of the proposed model in comparison to three state-of-the-arts. This method would be more suitable for the works of pointillism painters with a relatively uniform style, especially for natural scenes, otherwise, the results can be less satisfactory.
An MM Algorithm for the Frailty-Based Illness Death Model with Semi-Competing Risks Data
Authors: Huang Xifen , Xu Jinfeng , Guo Hao , Shi Jianhua , Zhao Wenjie
Published: October 2022

For analyzing multiple events data, the illness death model is often used to investigate the covariate–response association for its easy and direct interpretation as well as the flexibility to accommodate the within-subject dependence. The resulting estimation and inferential procedures often depend on the subjective specification of the parametric frailty distribution. For certain frailty distributions, the computation can be challenging as the estimation involves both the nonparametric component and the parametric component. In this paper, we develop efficient computational methods for analyzing semi-competing risks data in the illness death model with the general frailty, where the Minorization–Maximization (MM) principle is employed for yielding accurate estimation and inferential procedures. Simulation studies are conducted to assess the finite-sample performance of the proposed method. An application to a real data is also provided for illustration.
Treatment of Complex Two-Vessel Coronary Heart Disease with Single Left Internal Mammary Artery as T-Graft with Itself—A Retrospective Double Center Analysis of Short-Term Outcomes
Authors: Rustenbach Christian Jörg , Djordjevic Ilija , Eghbalzadeh Kaveh , Baumbach Hardy , Wendt Stefanie , Radwan Medhat , Marinos Spiro Lukas , Mustafi Migdat , Lescan Mario , Berger Rafal , Salewski Christoph , Sandoval Boburg Rodrigo , Steger Volker , Nemeth Attila , Reichert Stefan , Wahlers Thorsten , Schlensak Christian
Published: October 2022

Background and Objectives: The strategy of revascularization may be constrained in patients with insufficient bypass grafts and with increased risk of wound healing disorders. Among those with complex left-sided double-vessel disease in whom a percutaneous coronary intervention (PCI), as well as the surgical procedure of minimally invasive coronary artery bypass grafting via left minithoracotomy (MICS CABG), is not a treatment option, CABG using the left internal mammary artery as a T-graft with itself may be an effective treatment strategy. Materials and Methods: We reviewed the data from patients treated in Cologne and Tuebingen from 2019 to 2022. We included 40 patients who received left internal mammary artery (LIMA) grafting, and additional T-graft with the LIMA itself. The objective was focused on intraoperative and short-term outcomes. Results: A total of 40 patients were treated with the LIMA-LIMA T-graft procedure with a Fowler score calculated at 20.1 ± 3.0. A total of 37.5% of all patients had lacking venous graft material due to prior vein stripping, and 21 patients presented severe vein varicosis. An overall of 2.6 ± 0.5 distal anastomoses (target vessels were left anterior descending, diagonal, intermediate branch, and/or left marginal ramus) were performed, partly sequentially. Mean flow of LIMA-Left anterior descending (LAD) anastomosis was 59.31 ± 11.04 mL/min with a mean PI of 1.21 ± 0.18. Mean flow of subsequent T-Graft accounted for 51.31 ± 3.81 mL/min with a mean PI of 1.39 ± 0.47. Median hospital stay was 6.2 (5.0; 7.5) days. No incidence of postoperative wound healing disorders was observed, and all patients were discharged. There was one 30-day readmission with a diagnosis of pericardial effusion (2.5%). There was no 30-day mortality within the cohort. Conclusions: Patients requiring surgical myocardial revascularization due to complex two-vessel coronary artery disease (CAD) can be easily managed with LIMA alone, despite an elevated Fowler score and a promising outcome. A prospective study needs to be conducted, as well as longer term surveillance, to substantiate and benchmark the long-term results, as well as the patency rates.
Impact of Capsulotomy on Hip Biomechanics during Arthroscopy
Authors: Lee Hyeonjoon , Lim Wonbong , Lee Seunghyun , Jo Sungmin , Jo Suenghwan
Published: October 2022

Background and Objectives: Anterior capsulotomy is routinely performed in hip arthroscopy to improve joint visualization; however, this can partly or completely disrupt the stabilizing ligaments of the hip. This study aimed to report the effects of conventional and extensive arthroscopic capsulotomies on hip stability. Materials and Methods: Eight freshly frozen cadaveric pelvises were used in this study. The range of motion and translation were measured and compared among different capsular conditions utilized in hip arthroscopy, with a special interest in the iliofemoral ligament (IFL) and zona orbicularis (ZO). The conditions included intact capsule, interportal capsulotomy, T-capsulotomy, complete IFL disruption, and complete IFL and ZO disruption. Internal rotation at three flexion planes (−10°, 0°, and 30°) and external rotation at six flexion planes (−10°, 0°, 30°, 60°, 90°, and 110°) were measured with corresponding femoral head translation distance at the application of 2.5 Nm torque. Results: As compared to an intact capsule, a significant increase in external rotation was observed after interportal capsulotomy from −10° to 60° and after T-capsulotomy from −10° to 110° flexion. A significant translation was observed only with a T-capsulotomy, which ranged from 1.9 to 2.3 mm across the flexion angles. Compared with conventional interportal capsulotomy, disruption of the entire IFL resulted in a significant increase in external rotation in all flexion planes, and significant translation was accompanied by disruption of the ZO. Conclusions: Interportal capsulotomy can result in an increase in range of motion, and T-capsulotomy can lead to significant translation. Partial or complete tears of the IFL and ZO can result in further external rotation and translation.
Metallographic Study of Overlapped Laser Welds of Dissimilar Materials
Authors: Guzanová Anna , Janoško Erik , Draganovská Dagmar , Viňáš Ján , Tomáš Miroslav , Brezinová Janette , Maláková Silvia , Džupon Miroslav , Vojtko Marek
Published: October 2022

The paper deals with the metallographic analysis of overlapped laser welds of dissimilar materials based on galvanized and ungalvanized steels in various combinations. In addition to a gallery of metallographic sections, the paper presents the monitoring of weld defects, the measurement of selected weld geometrical characteristics and changes in weld microstructure by measuring the microhardness profile across the joint. The mixing of materials was monitored by area and line EDX analysis in the melting zone. Subsequently, the load carrying capacity of the formed joints was determined and compared with FEM simulation. Finally, the dependences of hardness and strength of welds on carbon content and carbon equivalent were determined.
Effects of Thermal Shock on the Microstructures and Mechanical Properties Evolution of 310S Welded Joints at 1100 °C
Authors: Jiang Yunlu , Kan Ying , Wu Changzhong , Chen Huaining
Published: October 2022

In order to reveal the effects of the glass solidification bottling process of high-level liquid radioactive wastes on the welded joints of containers, the microstructure evolution and mechanical properties of 310S stainless steel welded joints were investigated. For this purpose, samples were heat-treated in a resistance furnace at 1100 °C, with two groups of samples being thermally shocked and heat-treated in the furnace. The results indicated that the grain-size distribution changed from unimodal to bimodal for the thermally shocked samples, which was caused by abnormal growth due to the grain growth driving force during recrystallization. Spinel oxide ((Fe, Cr, Ni)3O4) and Cr2O3 were the main oxides at 1100 °C. The dislocations almost disappeared and needle-like structures that were rich in N and Cr formed in the welded joints after being thermally shocked. The tensile properties of the thermally shocked welded joints showed decreases in yield strength and plasticity. The fracture morphologies of the samples heated in the furnace and the as-welded samples presented with dimples. However, the morphologies of the fracture surfaces of the thermally shocked samples presented large numbers of secondary cracks and smooth characteristics.
Weather Prediction for Singapore—Progress, Challenges, and Opportunities
Authors: Lee Joshua Chun Kwang , Zhang Huqiang , Barker Dale Melvyn , Chen Song , Kumar Rajesh , An Byoung Woong , Sharma Kuldeep , Chandramouli Krishnamoorthy
Published: October 2022

Singapore is a tiny city-state located in maritime Southeast Asia. Weather systems such as localized thunderstorms, squalls, and monsoon surges bring extreme rainfall to Singapore, influencing the day-to-day conduct of stakeholders in many sectors. Numerical weather prediction models can provide forecast guidance, but existing global models struggle to capture the development and evolution of the small-scale and transient weather systems impacting the region. To address this, Singapore has collaborated with international partners and developed regional numerical weather prediction systems. Steady progress has been made, bringing added value to stakeholders. In recent years, complex earth system and ultra high-resolution urban models have also been developed to meet increasingly diverse stakeholder needs. However, further advancement of weather prediction for Singapore is often hindered by existing challenges, such as the lack of data, limited understanding of underlying processes, and geographical complexities. These may be viewed as opportunities, but are not trivial to address. There are also other opportunities that have remained relatively unexplored over Singapore and the region, such as the integration of earth system models, uncertainty estimation and machine learning methods. These are perhaps key research directions that Singapore should embark on to continue ensuring value for stakeholders.
Nanoindentation and Atomic Force Microscopy Derived Mechanical and Microgeometrical Properties of Tooth Root Cementum
Authors: Sadyrin Evgeniy , Lapitskaya Vasilina , Kuznetsova Tatyana , Yogina Diana , Maksyukov Stanislav , Aizikovich Sergei
Published: October 2022

In the present research, nanoindentation, atomic-force microscopy and optical microscopy were used to study the mechanical and microgeometrical parameters of tooth tissues. A nanoindentation test unit equipped with Berkovich indenter was used to determine the values of the reduced Young’s modulus and indentation hardness and both nanoindentation and atomic force microscopy using a diamond probe on a silicon cantilever were used to study microgeometrical parameters of human tooth root cementum. Three areas of cementum were studied: the cervical region near the dentine–enamel junction, the second third of the tooth root, and the apex of the tooth root. The interpretation of the results was carried out using the Oliver–Pharr method. It was established, that the mechanical properties of cementum increase from the cervical region to the central part of the root, then decrease again towards the apex of the tooth root. On the contrary, the microgeometrical characteristics of cementum practically do not demonstrate any change in the same direction. A decrease in the roughness parameters in the direction from cellular cementum to dentine was observed. Additionally, a decrease in the reduced Young’s modulus and indentation hardness of dentine in the cervical area compared to dentine in the crown part of the tooth was found using nanoindentation. The investigation of the dentine–cementum junction with high resolution revealed the interspaced collagen fiber bridges and epithelial rests of Malassez, whose sizes were studied. The parameters of the topographic features of the cementum in the vicinity of the lacunae of cementocytes were also established.
Magmatic Garnet and Magma Evolution in Cuonadong Leucogranites: Constraints from Petrology and Mineral Geochemistry
Authors: Yan Haibo , Yu Deshui , Wang Shoujing , Ma Chi
Published: October 2022

Located at the eastern segment of the Tethyan Himalayan tectonic unit, the Cuonadong leucogranites (muscovite granite and pegmatite) have a mineral assemblage of quartz, plagioclase, and alkali feldspar, as well as muscovite and garnet. Garnets in both muscovite granite and pegmatite belong to the almandine–spessartine solid solution, with minor andradite, grossular, and pyrope, and show a specific Mn zoning of a relatively rim-ward Mn depletion trend. However, a few garnets in pegmatite show grossular enrichment towards the rim. All the analyzed garnets are characterized by HREE enrichment and LREE depletion with obvious Eu anomalies. The difference is that garnets from the muscovite granite show distinct left-declined or flat HREE patterns, while those from the pegmatite are featured by flat or right-declined HREE patterns. Moreover, garnets from the pegmatite show relatively more distinct HREE- and Y-rich cores compared with those from the muscovite granite. The MnO concentration, spessartine content, and MnO/(MnO + FeO) ratio of the garnets from the Cuonadong dome increase from the muscovite granite to the pegmatite, suggesting that the pegmatite likely formed from a more evolved environment. Elevated grossular and CaO contents of the garnet rim in the pegmatite may reflect an influence of fluids in their composition. The major and trace element compositions and zoning textures of garnets from the Cuonadong leucogranites suggest a magmatic origin and a formation at moderately low temperatures and relatively low-pressure conditions. From the muscovite granite to the pegmatite, the system entered a fluid-rich environment and the garnets from the pegmatite likely crystallized from a lower-temperature fluid.
C. spinosa L. subsp. rupestris Phytochemical Profile and Effect on Oxidative Stress in Normal and Cancer Cells
Authors: Bacchetti Tiziana , Campagna Roberto , Sartini Davide , Cecati Monia , Morresi Camilla , Bellachioma Luisa , Martinelli Erika , Rocchetti Gabriele , Lucini Luigi , Ferretti Gianna , Emanuelli Monica
Published: October 2022

Spices, widely used to improve the sensory characteristics of food, contain several bioactive compounds as well, including polyphenols, carotenoids, and glucosynolates. Acting through multiple pathways, these bioactive molecules affect a wide variety of cellular processes involved in molecular mechanisms important in the onset and progress of human diseases. Capparis spinosa L. is an aromatic plant characteristic of the Mediterranean diet. Previous studies have reported that different parts (aerial parts, roots, and seeds) of C. spinosa exert various pharmacological activities. Flower buds of C. spinosa contain several bioactive compounds, including polyphenols and glucosinolates. Two different subspecies of C. spinosa L., namely, C. spinosa L. subsp. spinosa, and C. spinosa L. subsp. rupestris, have been reported. Few studies have been carried out in C. spinosa L. subsp. rupestris. The aim of our study was to investigate the phytochemical profile of floral buds of the less investigated species C. spinosa subsp. rupestris. Moreover, we investigated the effect of the extract from buds of C. spinosa subsp. rupestris (CSE) on cell proliferation, intracellular ROS levels, and expression of the antioxidant and anti-apoptotic enzyme paraoxonase-2 (PON2) in normal and cancer cells. T24 cells and Caco-2 cells were selected as models of advanced-stage human bladder cancer and human colorectal adenocarcinoma, respectively. The immortalized human urothelial cell line (UROtsa) and human dermal fibroblast (HuDe) were chosen as normal cell models. Through an untargeted metabolomic approach based on ultra-high-performance liquid chromatography quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS), our results demonstrate that C. spinosa subsp. rupestris flower buds contain polyphenols and glucosinolates able to exert a higher cytotoxic effect and higher intracellular reactive oxygen species (ROS) production in cancer cells compared to normal cells. Moreover, upregulation of the expression of the enzyme PON2 was observed in cancer cells. In conclusion, our data demonstrate that normal and cancer cells are differentially sensitive to CSE, which has different effects on PON2 gene expression as well. The overexpression of PON2 in T24 cells treated with CSE could represent a mechanism by which tumor cells protect themselves from the apoptotic process induced by glucosinolates and polyphenols.
Redox-Triggered Switching of Conformational State in Triple-Decker Lanthanide Phthalocyaninates
Authors: Martynov Alexander G. , Polovkova Marina A. , Gorbunova Yulia G. , Tsivadze Aslan Yu.
Published: October 2022

Double- and triple-decker lanthanide phthalocyaninates exhibit unique physical-chemical properties, particularly single-molecule magnetism. Among other factors, the magnetic properties of these sandwiches depend on their conformational state, which is determined via the skew angle of the phthalocyanine ligands. Thus, in the present work we report the comprehensive conformational study of substituted terbium(III) and yttrium(III) trisphthalocyaninates in solution depending on the substituents at the periphery of molecules, redox-states and nature of solvents. Conjunction of UV-vis-NIR spectroscopy and quantum-chemical calculations within simplified time-dependent DFT in Tamm–Dancoff approximation provided the spectroscopic signatures of staggered and gauche conformations of trisphthalocyaninates. Altogether, it allowed us to demonstrate that the butoxy-substituted complex behaves as a molecular switcher with controllable conformational state, while the crown-substituted triple-decker complex maintains a staggered conformation regardless of external factors. The analysis of noncovalent interactions within the reduced density gradient approach allowed to shed light on the nature of factors stabilizing certain conformers.
Detection of Hydrogen Sulfide in Sewer Using an Erbium-Doped Fiber Amplified Diode Laser and a Gold-Plated Photoacoustic Cell
Authors: Feng Chaofan , Giglio Marilena , Li Biao , Sampaolo Angelo , Patimisco Pietro , Spagnolo Vincenzo , Dong Lei , Wu Hongpeng
Published: October 2022

A photoacoustic detection module based on a gold-plated photoacoustic cell was reported in this manuscript to measure hydrogen sulfide (H2S) gas in sewers. A 1582 nm distributed feedback (DFB) diode laser was employed as the excitation light source of the photoacoustic sensor. Operating pressure within the photoacoustic cell and laser modulation depth were optimized at room temperature, and the long-term stability of the photoacoustic sensor system was analyzed by an Allan-Werle deviation analysis. Experimental results showed that under atmospheric pressure and room temperature conditions, the photoacoustic detection module exhibits a sensitivity of 11.39 μV/ppm of H2S and can reach a minimum detection limit (1σ) of 140 ppb of H2S with an integration time of 1 s. The sensor was tested for in-field measurements by sampling gas in the sewer near the Shanxi University canteen: levels of H2S of 81.5 ppm were measured, below the 100 ppm limit reported by the Chinese sewer bidding document.
Green Preparation of Durian Rind-Based Cellulose Nanofiber and Its Application in Aerogel
Authors: Xing Huwei , Fei Yongsheng , Cheng Jingru , Wang Congcong , Zhang Jingjing , Niu Chenxi , Fu Qian , Cheng Jiali , Lu Lingbin
Published: October 2022

In this study, a green, highly efficient and low energy consumption preparation method of cellulose nanofiber (CNF) was developed by using agricultural and forestry waste durian rinds as raw materials. The power of ultrasonic treatment was successfully reduced to only 360 W with low molecular weight liquid DMSO. The obtained durian rind-based CNF had a diameter of 8–20 nm and a length of several micrometers. It had good dispersion and stability in water, and could spontaneously cross-link to form hydrogel at room temperature when the concentration was more than 0.5%. The microscopic morphology and compressive properties of CNF aerogels and composite cellulose aerogels prepared from durian rind-based CNF were evaluated. It was found that CNF could effectively prevent the volume shrinkage of aerogel, and the concentration of CNF had a significant effect on the microstructure and mechanical properties of aerogel. The CNF aerogel with 1% CNF exhibited a sheet structure braced by fibers, which had the strongest compression performance. The porosity of CNF aerogels was high to 99%. The compressive strength of the composite cellulose aerogel with durian rind-based CNF was effectively enhanced.
Methane Production Characteristics of an Anaerobic Co-Digestion of Pig Manure and Fermented Liquid Feed
Authors: Hanum Farida , Atsuta Yoichi , Daimon Hiroyuki
Published: October 2022

Methane production characteristics of anaerobic co-digestion of pig manure (PM) and fermented liquid feed (FLF) were investigated in a continuous digester under mesophilic conditions. The experiment followed three phases. PM alone was digested in phase I. In phases II and III, PM and FLF were mixed in a ratio of 95:5 and 90:10 (% v/v), respectively. The specific methane yields (SMYs) during phases I, II, and III were 238, 278, and 326.8 mLCH4·gVS−1-added, respectively. It was due to the effect of balancing the feedstock carbon-to-nitrogen ratio by adding FLF. This improvement can also be attributed to the readily biodegradable compounds in the FLF. The higher SMY obtained in this study showed a positive synergistic effect in the anaerobic co-digestion of PM and FLF. The results also indicate that adding the FLF positively affected and maintained a constant pH level, avoiding volatile fatty acid accumulation and ammonia inhibition in the anaerobic digestion (AD). Thus, this study provides valuable information regarding the usage of unused or wasted FLF as a co-substrate for the practical AD of PM. The production of fermented liquid additives such as FLF to improve the methane production from the AD of PM is a potential novel alternative to food waste recycling in Japan, besides compost and animal feeding.
Microstructure, Mechanical and Electrical Properties of Hybrid Copper Matrix Composites with Fe Microspheres and rGO Nanosheets
Authors: Zhang Xinjiang , He Meng , Zhan Yongzhong , Yang Wenchao , Wu Kaifeng
Published: October 2022

Copper matrix composites have a wide application as magnetic conductive materials, electromagnetic materials, electrical discharge machining materials, etc. Such materials are expected to have a good combination of excellent electrical conductivity and good mechanical strength. In this work, micro/nano hybrid reinforcements with Fe microspheres and reduced graphene oxide (rGO) nanosheets were developed for copper matrix composites. The rGO/Fe/Cu powders were firstly wet-mixed and then densified by the vacuum hot-pressing sintering to obtain the bulk compacts. Microstructure, electrical conductivity and mechanical properties of such compacts were investigated. Microstructural result of as-sintered compacts shows that the Fe microspheres could distribute in the matrix uniformly, and rGO nanosheets exhibit both agglomerated and dispersed states. The grain size of Cu matrix decreased with the increase of the rGO content. Hardness, compression and tensile 0.2% yield strength of the as-sintered compacts were improved evidently by the addition of the hybrid Fe/rGO, comparing with pure Cu and single Fe-added composites. However, a lower electrical conductivity appeared in the more rGO-added composites, but still reached more than 33.0% international annealing copper standard (IACS). These performance change could be sought in the spatially geometrical distribution and characteristics of such micro/nano Fe/rGO hybrid addition, and the relevant mechanisms were discussed.