bluuebunny/crossref_metadata_2025 huggingface dataset:
Orthopedic Telemedicine Outpatient Practice Diagnoses Set during the First COVID-19 Pandemic Lockdown—Individual Observation
Authors: Glinkowski Wojciech Michał
Published: April 2022

The COVID-19 pandemic has caused a substantial intensification of the telemedicine transformation process in orthopedics since 2020. In the light of the legal regulations introduced in Poland, from the beginning of the SARS-CoV-2 pandemic, physicians, including orthopedic surgeons, have had the opportunity to conduct specialist teleconsultations. Teleconsultations increase epidemiological safety and significantly reduce the exposure of patients and medical staff to direct transmission of the viral vector and the spread of infections. The study aimed to describe diagnoses and clinical aspects of consecutive orthopedic teleconsultations (TC) during the pandemic lockdown. The diagnoses were set according to the International Classification of Diseases (ICD-10). Hybrid teleconsultations used smartphones and obligatory Electronic Health Record (EHR) with supplemental voice, SMS, MMS, Medical images, documents, and video conferencing if necessary. One hundred ninety-eight consecutive orthopedic teleconsultations were served for 615 women and 683 men (mean age 41.82 years ± 11.47 years). The most frequently diagnosed diseases were non-acute orthopedic disorders “M” (65.3%) and injuries “S” (26.3%). Back pain (M54) was the most frequent diagnosis (25.5%). Although virtual orthopedic consultation cannot replace an entire personal visit to a specialist orthopedic surgeon, in many cases, teleconsultation enables medical staff to continue to participate in providing medical services at a sufficiently high medical level to ensure patient and physician. The unified approach to TC diagnoses using ICD-10 or ICD-11 may improve further research on telemedicine-related orthopedics repeatability. Future research directions should address orthopedic teleconsultations’ practical aspects and highlight legal, organizational, and technological issues with their implementations.
Food Education, Cookery Books and School Canteens in the Fight against Malnutrition: The Case of the Spanish Edalnu Programme (1961–1986)
Authors: Tormo-Santamaria Maria , Bernabeu-Mestre Josep
Published: April 2022

The Spanish population completed its nutritional transition in the 1960s and 1970s, when it overcame the problems of malnutrition. Among the initiatives that made this possible, the Food and Nutrition Education Programme (Edalnu) (1961–1986) stands out. In addition to correcting the negative influence exerted by ignorance to nourish oneself correctly, it was intended to prevent the problems of overfeeding that most developed countries showed. The objective of this research addresses, in this context and from the parameters of applied history, the condition of the complementary pedagogical instrument that the Edalnu awarded to the school canteen in the fight against malnutrition, as well as the nutritional, dietetic, culinary and gastronomic criteria used for its operation. The results show that the school canteens sought to reinforce the food knowledge acquired in the classroom. Based on the dialogue between chefs and experts in nutrition and dietetics, balanced meals adapted to regional gastronomic diversity were prepared, which helped to promote, in line with current criteria, healthy and sustainable eating habits through traditional plant-based recipes, with a predominance of seasonal and local products, and with a complementary contribution of ingredients of animal origin.
How Do Team Cooperative Goals Influence Thriving at Work: The Mediating Role of Team Time Consensus
Authors: Li Mingze , Peng Shuting , Liu Liwen
Published: April 2022

Thriving at work is beneficial to the physical and mental health of individuals, promotes the innovation and development of organizations, and is a shield against job burnout. However, the current research on the antecedents of thriving at work lacks the exploration of team characteristics. This study introduces team temporal leadership as a moderating variable and team time consensus as a mediating variable to explore the relationship between team cooperative goals and thriving at work. Based on the analysis of 326 data from 92 teams, the results showed that: (1) Team cooperative goals have a significant positive impact on team time consensus, and team time consensus has a significant positive impact on team thriving at work; (2) Team time consensus mediates the relationship between team cooperative goals and team thriving at work; and (3) Team temporal leadership not only moderated the relationship between team cooperative goals and team time consensus, but also moderated the indirect effect of team cooperative goals on team thriving at work through team time consensus. This study enriches the research on the triggering mechanism of thriving at work to some extent and provides enlightenment for organizations to stimulate the state of thriving at work.
Adaptation and Validation of the Individual Lifestyle Profile Scale of Portuguese Older Adults Living at Home
Authors: Alves Faria Ana da Conceição , Martins Maria Manuela , Ribeiro Olga Maria Pimenta Lopes , Ventura-Silva João Miguel Almeida , Teles Paulo João Figueiredo Cabral , Laredo-Aguilera José Alberto
Published: April 2022

(1) Background: Unadjusted lifestyles have been the main cause of risk for the loss of years of healthy life. However, currently valid and reliable instruments to assess the lifestyles of the elderly are quite long and difficult to interpret. For this reason, the objective of this study was to adapt and validate the ‘Individual Lifestyle Profile’ (ILP) scale in a sample of elderly people; (2) Methods: A methodological study was carried out and a sample of 300 older adults enrolled in a Health Unit located in the North of Portugal was used, who responded to the scale. We examined internal consistency, predictive validity, and discriminative ability; (3) Results: After the Exploratory Factorial analysis, a solution was found with four factors that explain a variance of 67.8%. The designation of the factors was changed from the original scale, with the exception of one dimension, and they were called Health Self-management, Social Participation and Group Interaction, Citizenship and Physical Activity. The total internal consistency (Cronbach’s alpha) was 0.858, ranging from 0.666 to 0.860 in the mentioned factors; (4) Conclusions: The ILP scale proved to be easy to apply and presented a good reliability and validity index, based on internal consistency, AFE and AFC. The scale allows evaluating the lifestyle of older adults, and its use will be aimed at modifying behaviors associated with negative lifestyles of older adults and their individual needs.
Fast, Ungapped Reads Mapping Using Squid
Authors: Riccardi Christopher , Innocenti Gabriel , Fondi Marco , Bacci Giovanni
Published: April 2022

Advances in Next Generation Sequencing technologies allow us to inspect and unlock the genome to a level of detail that was unimaginable only a few decades ago. Omics-based studies are casting a light on the patterns and determinants of disease conditions in populations, as well as on the influence of microbial communities on human health, just to name a few. Through increasing volumes of sequencing information, for example, it is possible to compare genomic features and analyze the modulation of the transcriptome under different environmental stimuli. Although protocols for NGS preparation are intended to leave little to no space for contamination of any kind, a noticeable fraction of sequencing reads still may not uniquely represent what was intended to be sequenced in the first place. If a natural consequence of a sequencing sample is to assess the presence of features of interest by mapping the obtained reads to a genome of reference, sometimes it is useful to determine the fraction of those that do not map, or that map discordantly, and store this information to a new file for subsequent analyses. Here we propose a new mapper, which we called Squid, that among other accessory functionalities finds and returns sequencing reads that match or do not match to a reference sequence database in any orientation. We encourage the use of Squid prior to any quantification pipeline to assess, for instance, the presence of contaminants, especially in RNA-Seq experiments.
Telemedicine and Haemodialysis Care during the COVID-19 Pandemic: An Integrative Review of Patient Safety, Healthcare Quality, Ethics and the Legal Considerations in Singapore Practice
Authors: Haroon Sabrina , Voo Teck Chuan , Chua Hillary , Tan Gan Liang , Lau Titus
Published: April 2022

The COVID-19 pandemic has been an unprecedented health crisis for the general population as well as for patients with chronic illnesses such as those requiring maintenance dialysis. Patients suffering from chronic kidney disease requiring dialysis are considered a high-risk population. Multiple reports have highlighted an increased need for intensive care and higher death rates among this group of patients. Most maintenance dialysis patients are in-centre haemodialysis patients who receive treatment in shared facilities (community dialysis centres). The inability to maintain social distancing in these facilities has led to case clustering among patients and staff. This poses a substantial risk to the patients, their household members, and the wider community. To mitigate the risks of COVID-19 transmission, telemedicine was rapidly adopted in the past year by nephrologists and other allied-health staff to provide care via remote consultations and reviews. Telemedicine poses unique challenges even in an era where so much is performed online with a high degree of success and satisfaction. In applying distant clinical care for maintenance haemodialysis patients via telemedicine, there is a need to ensure adequate protection for the health and safety of patients as well as understand the ethical and legal implications of telemedicine. We discussed, in this article, these three core aspects of patient safety and quality, ethics and legal implications in telemedicine, and how each of these is crucial to the safe and effective delivery of care in general as well as unique aspects of this in Singapore.
Burnout and Online Medical Education: Romanian Students in Lockdown and Their Residency Choices
Authors: Silistraru Ioana , Olariu Oana , Ciubara Anamaria , Roșca Ștefan , Roșca Ramona Oana , Stanciu Silviu , Condratovici Alina Plesea , Ciureanu Ioan-Adrian
Published: April 2022

The primary aim of the study was to investigate the prevalence of burnout in Romanian medical students during the COVID-19 pandemic using the Maslach Burnout Inventory-General Survey for Students (MBI-GS(S)). The presence of burnout was assessed based on Exhaustion (EX), Cynicism (CY) and Professional Efficacy (PE) subscales. The secondary aim of the study was to identify the presence of intentional shift in medical specialty compared to their initial pursued choice within the population investigated. Data was collected online at the end of 2020 and beginning of 2021 through a licensed, customized MBI-GS(S) questionnaire from a sample of 126 Romanian medical students at the two leading medical schools in the country, Iasi (N = 56) and Cluj Napoca (N = 70). Descriptive statistics and bivariate correlations were also applied to describe the data set (age and gender of participants) and the relationship between variables (EX, CY, PE). Subsequently, the MBI-GS(S) group report revealed that 36.5% of the medical students in the sample (46) experienced burnout, with problematic results both in Exhaustion and Cynicism. Exhaustion and Cynicism, which contribute to burnout, showed high scores compared to the average scale (EX = 3.5/2.4; CY = 2.8/1.8), while the Professional Efficacy score was relatively high (PE = 3.8/4.4), showing a protective effect and burnout reduction. One of the main conclusions is that the consequences of burnout in medical students plays a significant role in shaping the future healthcare practitioners’ perception of the medical profession and of patients’ wellbeing. Exhaustion and Cynicism are mainly associated with depersonalization and disconnection from the patient. Another conclusion of the study is that about one third of the respondents (30% Cluj students and 37.5% Iasi students) considered changing residency options. The pandemic has also revealed the limitations of and challenges facing current medical education, and that further research is required to assess the trends in prevalence of burnout in medical students.
Methodology and Tools to Integrate Industry 4.0 CPS into Process Design and Management: ISA-88 Use Case
Authors: Garcia Ander , Oregui Xabier , Arrieta Unai , Valverde Iñigo
Published: April 2022

Once an industrial process is designed, the real implementation of the process control is programmed into Supervisory Control and Data Acquisition (SCADA) and Programmable Logic Controller (PLC) devices on the shop floor. These devices are programmed with their low-level coding languages. This presents several drawbacks, such as inconsistencies and naming errors between the design and the implementation steps, or difficulties in integrating new Industry 4.0 functionalities. This paper presents a design and management methodology, and a software architecture to overcome these drawbacks. The objective of the methodology is the interconnectivity of domain knowledge, software, and hardware components to automatically generate Industry 4.0 Cyber-Physical Systems (CPS) for industrial processes. The methodology is composed of five main steps: designing the process, programming the PLC, capturing data, managing the process and visualizing it. Based on the methodology and the architecture, a set of tools targeting ISA-88 processes has been implemented and validated. IEC-61512 (also known as ANSI/ISA-88) is a standard addressing batch process control. It follows a design philosophy for describing equipment and procedures, equally applicable to manual processes. The methodology has been validated on a process controlled by a Siemens 1200 PLC. The main advantages of this methodology identified during the validation are: (i) reduction in the time required to design the ISA-88 process, (ii) reduction in the PLC programming time and associated errors, (iii) automatic integration of a CPS with data capture and visualization functionalities, and (iv) remote management of the process.
Age Moderates the Effect of Injury Severity on Functional Trajectories in Traumatic Brain Injury: A Study Using the NIDILRR Traumatic Brain Injury Model Systems National Dataset
Authors: Winter Laraine , Mensinger Janell L. , Moriarty Helene J. , Robinson Keith M. , McKay Michelle , Leiby Benjamin E.
Published: April 2022

Age is a risk factor for a host of poor outcomes following traumatic brain injury (TBI), with some evidence suggesting that age is also a source of excess disability. We tested the extent to which age moderates the effect of injury severity on functional trajectories over 15 years post injury. Data from 11,442 participants from the 2020 National Institute of Disability and Independent Living Rehabiitation Research (NIDILRR) Traumatic Brain Injury Model Systems (TBIMS) National Dataset were analyzed using linear mixed effects models. Injury severity was operationally defined using a composite of Glasgow Coma Scale scores, structural imaging findings, and the number of days with post-trauma amnesia. Functioning was measured using the Glasgow Outcomes Scale-Extended. Age at injury was the hypothesized moderator. Race, ethnicity, sex, education, and marital status served as covariates. The results showed a significant confounder-adjusted effect of injury severity and age of injury on the linear slope in functioning. The age effect was strongest for those with mild TBI. Thus, the effects of injury severity on functional trajectory were found to be moderated by age. To optimize outcomes, TBI rehabilitation should be developed specifically for older patients. Age should also be a major focus in TBI research.
Void Content Reduction in 3D Printed Glass Fiber-Reinforced Polymer Composites through Temperature and Pressure Consolidation
Authors: Hetrick Dakota R. , Sanei Seyed Hamid Reza , Ashour Omar
Published: April 2022

To improve the properties of additively manufactured parts to be used in high-end applications, intrinsic defects occurring during the printing process need to be minimized. Defects such as void can significantly degrade the mechanical properties of the resulted parts. The presence of void is more evident in composite printed parts due to the inhomogeneity of the specimen. In this study, composite rectangular coupons printed with a Markforged Mark Two printer were manufactured with different fiber orientations and stacking sequences. A void content reduction/consolidation process, consisting of applying pressure at different temperature levels, was developed and implemented to remove the voids in form of air bubbles trapped in the specimen. A two-part mold with female and male components with the same dimensions as the rectangular specimen was designed and machined to be used in a hot press process. The success of the approach was evaluated by calculating the density of the specimen pre- and post-consolidation. The void content reduction results were highly dependent on fiber orientation; however, the density increased for all tested specimens, confirming the reduction in porosity.
Poly(methyl methacrylate) Nanocomposite Foams Reinforced with Carbon and Inorganic Nanoparticles—State-of-the-Art
Authors: Kausar Ayesha , Bocchetta Patrizia
Published: April 2022

Polymeric nanocomposite foams have attracted increasing research attention for technical reasons. Poly(methyl methacrylate) is a remarkable and viable thermoplastic polymer. This review highlights some indispensable aspects of poly(methyl methacrylate) nanocomposite foams with nanocarbon nanofillers (carbon nanotube, graphene, etc.) and inorganic nanoparticles (nanoclay, polyhedral oligomeric silsesquioxane, silica, etc.). The design and physical properties of poly(methyl methacrylate) nanocomposite foams have been deliberated. It has been observed that processing strategies, nanofiller dispersion, and interfacial interactions in poly(methyl methacrylate)–nanofiller have been found essential to produce high-performance nanocellular foams. The emergent application areas of the poly(methyl methacrylate) nanocomposite foams are electromagnetic interference shielding, sensors, and supercapacitors.
All-Cellulose Composites Properties from Pre- and Post-Consumer Denim Wastes: Comparative Study
Authors: Baghaei Behnaz , Johansson Belinda , Skrifvars Mikael , Kadi Nawar
Published: April 2022

This study reports the recycling of discarded denim textiles by the production of all-cellulose composites (ACCs). Discarded denim fabrics were shredded into fibers and then made into nonwoven fabrics by carding and needle punching. The produced nonwoven fabrics were converted to ACCs by one-step and two-step methods using an ionic liquid (IL), 1-butyl-3-methyl imidazolium acetate ([BMIM][Ac]). In this study, the effect of different ACC manufacturing methods, denim fabrics with different contents (a 100% cotton denim (CO) and a blend material (cotton, poly-ester and elastane (BCO)) and reusing of IL as a recycled cellulose solvent on the mechanical pro-perties of the formed ACCs were investigated. The ACCs were characterized according to their tensile and impact properties, as well as their void content. Microscopic analysis was carried out to study the morphology of a cross-section of the formed composites. The choice of the one-step method with recycled IL, pure IL or with a blend material (BCO) had no influence on the tensile properties. Instead, the result showed that the two-step method, with and without DMSO, will influence the E-modulus but not the tensile strength. Regarding the impact properties of the samples, the only factor likely to influence the impact energy was the one-step method with CO and BCO.
Influence of Matrix Strength on Bridging Performance of Fiber-Reinforced Cementitious Composite with Bundled Aramid Fiber
Authors: Kanakubo Toshiyuki , Shi Haohui , Wang Jin
Published: April 2022

The bundled aramid fiber has good bond properties in the cementitious matrix, and is expected to have high bridging performance in the fiber-reinforced cementitious composite (FRCC). To investigate the influence of matrix strength on the bridging performance of FRCC with the bundled aramid fiber, the uniaxial tension test of FRCC, the pullout test for an individual fiber, and the calculation of bridging law are conducted with the main parameters of matrix strength and fiber volume fraction. From the test results, the maximum tensile load of FRCC and the maximum pullout load of an individual fiber increase as the matrix strength also increases. The calculation result of the bridging law considering the effect of matrix strength expresses the bridging performance of the bundled aramid fiber well. The calculation result also shows that the bridging strength has a linear relationship up to a compressive strength of around 50 MPa.
Coastal Vulnerability: A Brief Review on Integrated Assessment in Southeast Asia
Authors: Noor Noorashikin Md , Abdul Maulud Khairul Nizam
Published: April 2022

Coastal zones are an essential part of maintaining sustainability in the world. Coastal regions have gained importance due to various factors, including high ecological production, dense population, industry compatibility, waste disposal, leisure, transportation, and development of military strategies. Coasts are often on the move and must adapt while nature constantly works to maintain balance. Southeast Asia has gained prominence due to its rich ecosystem, high productivity, and densely populated coastal region. In light of this, the coastlines of Southeast Asia are threatened by various factors, including global climate change and human activities. These factors exacerbate the shoreline erosion, frequent catastrophic events, rising sea levels, and saltwater intrusion. Coastal management has become one of the most important challenges of the past decade. The coastal vulnerability index (CVI) was developed to identify and manage vulnerable locations along the coast. Thus, this review attempts to summarize coastal vulnerability in Southeast Asian based on journals and reports. Topics covered include: (1) introduction to coastal vulnerability, (2) methods for determining coastal vulnerability, (3) factors influencing coastal vulnerability (4) associated coastal vulnerability, (5) assessment gaps, and (6) further courses of action. Consequently, assessment of coastal vulnerability will support Southeast Asian coastal communities in guiding mitigation strategies to manage coastal threats in future climate change and urban development.
Removal of Petroleum Hydrocarbons from Brackish Water by Natural and Modified Sorbents
Authors: Paulauskiene Tatjana , Uebe Jochen , Kryzevicius Zilvinas , Kaskova Valeriia , Katarzyte Marija , Overlingė Donata
Published: April 2022

Crude oil and petroleum products made from it are increasingly being extracted and consumed worldwide as an important energy source. During necessary transportation, e.g., by tanker, an oil spill might occur, which leads to water pollution by oil. One of the methods of cleaning up oil spills is to use sorbents, preferably made from natural materials. This study evaluates the remediation efficiency of brackish water polluted with crude oil, marine diesel oil (MDO) and lubricating oil. The experiment was performed with three different sorbents (straw, straw modified with methoxytrimethylsilanes (MTMS) and wood chip shavings) and without them. The evaporation loss and the dissolved and sorbed fractions of oil were measured by gas chromatography (GC) to evaluate remediation efficiency. Hydrophobization made the natural sorbents buoyant for the duration of the experiment, with only a slight increase in the maximum sorption capacity. The sorbents increased the evaporation of the oils and also of the water, reduced the proportion of the oil dissolved in water and retained the sorbed proportion for the lubricating oil and partly for the MDO, to such an extent that it could not be extracted entirely even after a 60-min extraction time.
Identification and Phylogenetic Analysis of Chitin Synthase Genes from the Deep-Sea Polychaete Branchipolynoe onnuriensis Genome
Authors: Choi Hyeongwoo , Kim Sang Lyeol , Jeong Man-Ki , Yu Ok Hwan , Eyun Seongil
Published: April 2022

Chitin, one of the most abundant biopolymers in nature, is a crucial material that provides sufficient rigidity to the exoskeleton. In addition, chitin is a valuable substance in both the medical and industrial fields. The synthesis of chitin is catalyzed by chitin synthase (CHS) enzymes. Although the chitin synthesis pathway is highly conserved from fungi to invertebrates, CHSs have mostly only been investigated in insects and crustaceans. Especially, little is known about annelids from hydrothermal vents. To understand chitin synthesis from the evolutionary view in a deep-sea environment, we first generated the whole-genome sequencing of the parasitic polychaete Branchipolynoe onnuriensis. We identified seven putative CHS genes (BonCHS1-BonCHS7) by domain searches and phylogenetic analyses. This study showed that most crustaceans have only a single copy or two gene copies, whereas at least two independent gene duplication events occur in B. onnuriensis. This is the first study of CHS obtained from a parasitic species inhabiting a hydrothermal vent and will provide insight into various organisms’ adaptation to the deep-sea hosts.
Recent Developments in the Diagnosis of Mucormycosis
Authors: Dannaoui Eric
Published: April 2022

Mucormycosis is a potentially fatal infection that presents in different clinical forms and occurs in patients with various risk factors. Recently, the COVID-19 epidemic has been responsible for an increase in the incidence of mucormycosis, particularly in India. As with other invasive filamentous fungal infections, there are no specific clinical or radiological signs, and we have fewer diagnostic tools available than for other invasive fungal infections. Therefore, the diagnosis of Mucormycosis remains difficult. Nevertheless, for optimal management, early and accurate diagnosis is important. According to the latest recommendations, diagnosis is based on direct examination of clinical specimens, and/or histopathology, and culture. There are also molecular tools for direct detection from clinical specimens, but these techniques are moderately recommended. The main problems with these molecular techniques are that, until now, they were not very well standardized; there was a great heterogeneity of DNA targets and methods, which resulted in variable sensitivity. It is in this field that most advances have been made in the last two years. Indeed, recent studies have evaluated the performance and kinetics of Mucorales qPCR in serum and have shown good sensitivity and specificity. Large inter-laboratory evaluations of qPCR in serum have also been performed and have demonstrated good qualitative and quantitative reproducibility. These new results suggest the use of Mucorales qPCR as part of the diagnostic strategy for mucormycosis. One way to achieve better reproducibility could be to use commercial methods. Currently, there are at least three commercial qPCRs for Mucorales (MucorGenius from PathoNostics, MycoGenie from Ademtech, and Fungiplex from Bruker) that can be used to test serum, respiratory samples, or biopsies. However, to date, there has been little evaluation of these methods. Overall, Mucorales PCR in tissue samples, in respiratory samples, and in serum is promising and its addition as a diagnostic tool in the definitions of invasive mucormycosis should be discussed.
Characterization of Fusarium acuminatum: A Potential Enniatins Producer in Tunisian Wheat
Authors: Chakroun Yasmine , Oueslati Souheib , Pinson-Gadais Laetitia , Abderrabba Manef , Savoie Jean-Michel
Published: April 2022

Fusarium Head Blight (FHB), caused by multiple species of Fusarium in small grain cereals, is a significant and long-standing problem anywhere in the world. Knowing regional Fusarium spp. present on non-symptomatic grains and their potential for mycotoxin production is of concern for identifying novel actions for FHB and mycotoxin management, such as treatments with essential oils. Analyzing the mycotoxin content of grains from non-symptomatic ears of different wheat varieties cultivated in Tunisia, we isolated Fusaria specimens identified as F. culmorum and F. acuminatum using analysis of the partial DNA sequence of the β-tubulin gene and ITS region. Two isolates of the latter species, uncommon in cereal grains in this region until now, were shown to be effective producers of enniatins in vitro, with 1390 and 3089 µg g−1 mycelial biomass (dry) in 11-day-old cultures. The susceptibility of an isolate of F. acuminatum to the fungistatic and antimycotoxin effects of eight essential oils was measured. Essential oils from Ammoides pusilla and Thymus capitatus used at 0.1 µL mL−1 in an agar culture medium, affected the mycelial growth by 55% and 79%, respectively and reduced the accumulation of enniatins per unit of mycelial colony by 26% and 52%, respectively. Finally, F. acuminatum was shown to be a contaminant of wheat grains in Tunisia and it may contribute to the contamination in enniatins. Two essential oils of Tunisian plants could be used for developing a biofungicide limiting both its mycelial growth and its accumulation of mycotoxins in grains.
Forecasting Urban Land Use Change Based on Cellular Automata and the PLUS Model
Authors: Xu Linfeng , Liu Xuan , Tong De , Liu Zhixin , Yin Lirong , Zheng Wenfeng
Published: April 2022

Nowadays, cities meet numerous sustainable development challenges in facing growing urban populations and expanding urban areas. The monitoring and simulation of land use and land-cover change have become essential tools for understanding and managing urbanization. This paper interprets and predicts the expansion of seven different land use types in the study area, using the PLUS model, which combines the Land use Expansion Analysis Strategy (LEAS) and the CA model, based on the multi-class random patch seed (CARS) model. By choosing a variety of driving factors, the PLUS model simulates urban expansion in the metropolitan area of Hangzhou. The accuracy of the simulation, manifested as the kappa coefficient of urban land, increased to more than 84%, and the kappa coefficient of other land use types was more than 90%. To a certain extent, the PLUS model used in this study solves the CA model’s deficiencies in conversion rule mining strategy and landscape dynamic change simulation strategy. The results show that various types of land use changes obtained using this method have a high degree of accuracy and can be used to simulate urban expansion, especially over short periods.
Properties and Microstructures of Crushed Rock Based-Alkaline Activated Material for Roadway Applications
Authors: Suwan Teewara , Jitsangiam Peerapong , Thongchua Hemwadee , Rattanasak Ubolluk , Bualuang Thanon , Maichin Phattharachai
Published: April 2022

The worldwide demand for roads to serve global economic growth has led to the increasing popularity of road improvement using cement. This, in turn, has led to increased demand for cement and the associated problem of CO2 emissions. Alkaline-activated materials (AAMs) could be an alternative binder for relatively low strength construction and rehabilitation as a cement replacement material. Compared to other applications, the lower strength requirements of road construction materials could ease any difficulties with AAM production. In this study, crushed rock (CR) was used as a prime raw material. The mechanisms and microstructures of the hardened AAM were investigated along with its mechanical properties. The results showed that CR-based AAM with an optimum mixture of 5 M of NaOH concentration, an SS/SH ratio of 1.00, and a liquid alkaline-to-binder (L/B) ratio of 0.5 could be used for roadway applications. At this ratio, the paste samples cured at room temperature (26 ± 3 °C) had an early compressive strength (3 days-age) of 3.82 MPa, while the paste samples cured at 60 °C had an early compressive strength of 6.45 MPa. The targeted strength results were able to be applied to a cement-treated base (CTB) for pavement and roadway applications (2.1 to 5.5 MPa).
A New BCN Compound with Monoclinic Symmetry: First-Principle Calculations
Authors: Ma Zhenyang , Tang Chunzhi , Shi Chunlei
Published: April 2022

In this study, we predicted and investigated a new light-element compound B-C-N in Pm phase, denoted as Pm-BCN, using density functional theory. Pm-BCN is mechanically, dynamically, and thermodynamically stable. The elastic moduli of Pm-BCN are larger than those of other B-C-N and light-element compounds, such as P213 BN, B2C3, P4/m BN, Pnc2 BN, and dz4 BN. By studying the mechanical anisotropy of elastic moduli, we proved that Pm-BCN is a mechanically anisotropic material. In addition, the shear anisotropy factors A2 and ABa of Pm-BCN are smaller than those of the seven B-C-N compounds mentioned in this paper. Pm-BCN is a semiconductor material with an indirect and wide band gap, suggesting that Pm-BCN can be applied in microelectronic devices.
Experimental Study on the Salt Freezing Durability of Multi-Walled Carbon Nanotube Ultra-High-Performance Concrete
Authors: Liu Guifeng , Zhang Huadi , Liu Jianpeng , Xu Shuqi , Chen Zhengfa
Published: April 2022

Ultra-high-performance concrete (UHPC) is a new type of high-performance cement-based composite. It is widely used in important buildings, bridges, national defense construction, etc. because of its excellent mechanical properties and durability. Freeze thaw and salt erosion damage are one of the main causes of concrete structure failure. The use of UHPC prepared with multi-walled carbon nanotubes (MWCNTs) is an effective method to enhance the durability of concrete structures in complex environments. In this work, the optimal mix proportion based on mechanical properties was obtained by changing the content of MWCNTs and water binder ratio to prepare MWCNTs UHPC. Then, based on the changes in the compressive strength, mass loss rate, and relative dynamic modulus of elasticity (RDME), the damage degree of concrete under different salt erosion during 1500 freeze-thaw (FT) cycles was analyzed. The changes in the micro pore structure were characterized by scanning electron microscope (SEM) and nuclear magnetic resonance (NMR). The test results showed that the optimum mix proportion at the water binder ratio was 0.19 and 0.1% MWCNTs. At this time, the compressive strength was 34.1% higher and the flexural strength was 13.6% higher than when the MWCNTs content was 0. After 1500 salt freezing cycles, the appearance and mass loss of MWCNTs-UHPC prepared according to the best ratio changed little, and the maximum mass loss was 3.18%. The higher the mass fraction of the erosion solution is, the lower the compressive strength and RDME of concrete after FT cycles. The SEM test showed that cracks appeared in the internal structure and gradually increased due to salt freezing damage. However, the microstructure of the concrete was still relatively dense after 1500 salt freezing cycles. The NMR test showed that the salt freezing cycle has a significant influence on the change in the small pores, and the larger the mass fraction of the erosion solution, the smaller the change in the proportion of pores. After 1500 salt freezing cycles, the samples did not fail, which shows that MWCNTs UHPC with a design service life of 150 years has good salt freezing resistance under the coupling effect of salt corrosion and the FT cycle.
Effects of Tung Oil Composite Regenerating Agent on Rheological Properties and Microstructures of Reclaimed Asphalt Binder
Authors: Wang Qimin , Ye Qunshan , Luo Junhui , Xie Cheng , Liu Haobin , Liu Jianhua , Qin Mengnan
Published: April 2022

The single light oil regenerating agent has certain limitations on the performance recovery of aged asphalt. In this study, tung oil, dioctyl phthalate (DOP), C9 petroleum resin, and organic montmorillonite (OMMT) were used to prepare the composite regenerating agent, and its optimal mix proportion was determined by the orthogonal experimental design. The rheological properties and anti-aging performance of reclaimed asphalt were studied by the dynamic shear rheometer (DSR) and bending beam rheometer (BBR); and the Fourier transform infrared (FTIR) spectrometer, gel permeation chromatography (GPC), and scanning electron microscope (SEM) were adopted to explore its microstructure, morphology, and mechanism of action. The results show that with the addition of tung oil composite regenerating agent, the rheological properties of aged asphalt can be effectively recovered, even better than that of base asphalt. By using the complex modulus aging index (CMAI) and phase angle aging index (PMAI) it is found that the anti-aging performance of reclaimed asphalt is better than that of base asphalt. With the optimal content of the tung oil composite regenerating agent, the contents of characteristic functional groups and macromolecular asphaltenes in the aged asphalt can be reduced, indicating that the composite regenerating agent is beneficial to the dispersion and dissolution of polar substances in the aged asphalt. After aging, a large number of wrinkles appear on the surface of the asphalt. However, the addition of the tung oil composite regenerating agent can make the asphalt surface smooth, which indicates that the tung oil composite regenerating agent can restore the microstructure and morphology of aged asphalt to a certain extent.
Method for Manufacturing Corn Straw Cement-Based Composite and Its Physical Properties
Authors: Niu Boyu , Kim Byeong Hwa
Published: April 2022

This paper introduces an innovative method for making cement-based composites from corn straw plants, and investigates the strength, thermal conductivity, and hydration characteristics of the composites. Corn straw is a natural, renewable, and breathable thermal insulation composite that contains cellular sealed pores. Corn straw contains a large amount of soluble cellulosic sugar, which hinders the hydration reaction of Portland cement and affects the use of corn straw as a building material. In this study, a 3 wt.% siliceous solution was used for surface treatment of corn straw particles to prevent cellulosic sugar from affecting the hydration performance of Portland cement. The composition of added cement-based composite materials with treated corn straw at the dosage of 11–20 wt.% was investigated. The test results showed that the corn straw cement-based composite (CSCC) had an optimal thermal conductivity of 0.102–0.112 (W/(m·K)) and a minimum compressive strength of above 1 MPa. The hydration performance of four typical CSCCs was examined using XRD, SEM, and EDS. The experimental results of this study may help to increase the comprehensive utilization of corn straw. The manufacturing method of the composite materials is simple, effective, and convenient for popularization and application, and it provides a new important technical measure to solve the problem of high energy consumption in rural houses.
Electrochemical Evaluation of Stress Corrosion Cracking Susceptibility of Ti-6Al-3Nb-2Zr-1Mo Alloy Welded Joint in Simulated Deep-Sea Environment
Authors: Liu Haochen , Bai Xuehan , Li Zhen , Fan Lin , Tang Junlei , Lin Bing , Wang Yingying , Sun Mingxian
Published: April 2022

Titanium alloys have high specific strength and excellent corrosion resistance and have been applied in deep-sea engineering fields. However, stress corrosion cracking may become one of the biggest threats to the service safety of a high-strength titanium alloy, as well as its weldment. In this work, stress corrosion cracking of a gas-tungsten-arc-welded Ti-6Al-3Nb-2Zr-1Mo (Ti6321) alloy influenced by the applied potentials in simulated deep-sea and shallow-sea environments was investigated by combining slow strain rate testing with electrochemical measurements. The results showed that the service environment and applied potential have a substantial effect on the stress corrosion cracking behavior of the Ti6321 welded joint. The Ti6321 welded joint exhibited higher stress corrosion susceptibility in a simulated deep-sea environment and at a strong polarization level owing to the diminishing protection of the passive film under passivation inhibition and the enhancement of the hydrogen effect. The fracture of a Ti6321 welded joint in the weld material could be attributed to the softening effect of the thick secondary α within the coarse-grained martensite. The electrochemical evaluation model of stress corrosion cracking susceptibility of a Ti6321 welded joint in a simulated marine environment was established by adding the criterion in the passivation region based on the literature model, and four potential regions corresponding to different stress corrosion cracking mechanisms were classified and discussed. Our study provides useful guidance for the deep-sea engineering applications of Ti6321 alloys and a rapid assessment method of stress corrosion risk.
Rapid Test Method for Evaluating Inhibiting Effectiveness of Supplementary Cementitious Materials on Alkali–Silica Reaction Expansion of Concrete
Authors: Yi Lei , Mao Zhongyang , Deng Min , Liu Xiang , Fan Zhiyuan , Huang Xiaojun , Zhang Tao , Tang Mingshu
Published: April 2022

At present, there are many problems in various tests when judging the alkali activity of aggregates. The most practical engineering concrete prism test (CPT) takes one year, and the concrete suppression method needs two years. The aim of this paper is to discuss inhibiting effectiveness of supplementary cementitious materials (SCMs) on alkali–silica reaction (ASR) expansion of concrete and evaluate this rapid test method. Three kinds of aggregates were selected by chemical analysis, XRD and petrographic analysis. The high alkali–silicic acid activity of three aggregates was determined by accelerated mortar bars, concrete microbars and CPT. The expansion of concrete specimens made of three kinds of aggregates was measured and analyzed by using the method of length measurement. By changing the curing temperature to 40 °C, 60 °C and 80 °C, the test period of CPT is accelerated. It proved that the expansion of CPT is larger at 60 °C and smaller at 40 °C. The inhibition test was also accelerated by adding different proportion of SCMs (fly ash or blast furnace slag) and adjusting the curing temperature to 60 °C and 80 °C. On this basis, the inhibition test was accelerated by changing NaOH solution instead of moist air curing. The test period of the accelerated inhibition test can be effectively shortened from two years to 4 months, The expansion trend of each parameter and specimen is evaluated, the evaluation cycle can be adjusted to 5–6 months. The microscopic reaction characteristics of concrete specimens were investigated by means of SEM. According to each parameter and criterion, the judging standard of concrete rapid test and rapid restraint test is given in this paper.
SiC/MoSi2-SiC-Si Oxidation Protective Coatings for HTR Graphite Spheres with Residual Si Optimized
Authors: Wei Xiaoyu , Yang Hui , Zhao Hongsheng , Liu Xiaoxue , Zhang Kaihong , Li Ziqiang , Gao Yuan , Liu Bing
Published: April 2022

SiC/MoSi2-SiC-Si coatings for nuclear graphite spheres with different Si-Mo ratios were prepared through two-step pack cementation. XRD, SEM and EDS techniques were used to analyze the composition and microstructure of the coatings. The oxidation resistance performance of the composites at 1773 K, in static air, was investigated. The results showed that the SiC-MoSi2-Si coating could be divided into a denser inner layer and a loose outer layer, as free Si would infiltrate into the inner micropores of the coating under capillary force. When the Si/Mo ratio of the second pack cementation was 7:1, the thickness of the denser inner layer basically reached the maximum and exhibited excellent oxidation resistance ability, with a weight gain of 0.19% after 200 h oxidation. The performance improvement was analyzed as a result of the addition of SiC and C powder in the pack cementation process, effectively increasing the phase interfaces to relax the thermal stress in the coating. With different Si-Mo ratios, the content of residual Si and the formation rate of SiO2 glass layer on the coating surface were also different, thus affecting the anti-oxidation performance. The main reactions occurring at different stages of the oxidation curve were also discussed.
Active Assistive Design and Multiaxis Self-Tuning Control of a Novel Lower Limb Rehabilitation Exoskeleton
Authors: Pan Cheng-Tang , Lee Ming-Chan , Huang Jhih-Syuan , Chang Chun-Chieh , Hoe Zheng-Yu , Li Kuan-Ming
Published: April 2022

This paper presented the mechanical design and control of a lower limb rehabilitation exoskeleton named “the second lower limb rehabilitation exoskeleton (LLRE-II)”. The exoskeleton with a lightweight mechanism comprises a 16-cm stepless adjustable thigh and calf rod. The LLRE-II weighs less than 16 kg and has four degrees of freedom on each leg, including the waist, hip, knee, and ankle, which ensures fitted wear and comfort. Motors and harmonic drives were installed on the joints of the hip and knee to operate the exoskeleton. Meanwhile, master and slave motor controllers were programmed using a Texas Instruments microcontroller (TMS320F28069) for the walking gait commands and evaluation boards (TMS320F28069/DRV8301) of the joints. A self-tuning multiaxis control system was developed, and the performance of the controller was investigated through experiments. The experimental results showed that the mechanical design and control system exhibit adequate performance. Trajectory tracking errors were eliminated, and the root mean square errors reduced from 6.45 to 1.22 and from 4.15 to 3.09 for the hip and knee, respectively.
Feature-Based and Process-Based Manufacturing Cost Estimation
Authors: Ning Fangwei , Qu Hongquan , Shi Yan , Cai Maolin , Xu Weiqing
Published: April 2022

The demand for mass custom parts is increasing, estimating the cost of parts to a high degree of efficiency is a matter of great concern to most manufacturing companies. Under the premise of machining operations, cost estimation based on features and processes yields high estimation accuracy, but it necessitates accurately identifying a part’s machining features and establishing the relationship between the feature and the cost. Accordingly, a feature recognition method based on syntactic pattern recognition is proposed herein. The proposed method provides a more precise feature definition and easily describes complex features using constraints. To establish the relationships between geometric features, processing modes, and cost, this study proposes a method of describing the features and the processing mode using feature quantities and adopts deep learning technology to establish the relationship between feature quantities and cost. By comparing a back propagation (BP) network and a convolutional neural network (CNN) it can be concluded that a CNN using the “RMSProp” optimizer exhibits higher accuracy.
Vector-Based Magnetic Circuit Modelling of Induction Motors
Authors: Kidd Braden
Published: April 2022

Electro-mechanical devices incorporating rotating magnetic fields can be modelled using a wide range of analytical techniques. Choosing a modelling technique usually requires a trade off between computational efficiency and accuracy. Magnetic flux-based models aim to achieve an optimum balance between computational intensity and accuracy, as required for real time control applications. This paper demonstrates how vector-based magnetic circuit equations can be used to describe the operational characteristics of an induction motor at a more fundamental level than commonly used magnetic flux models. Doing so allows for closed form equations to be derived directly from device-specific geometry. The resultant model has advantages of numerical method-based analytical techniques while retaining the computational efficiency of closed form equations.