bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating the Expression of Candidate Homeobox Genes and Their Role in Local-Site Inflammation in Mucosal Tissue Obtained from Children with Non-Syndromic Cleft Lip and Palate
Authors: Jain Nityanand , Pilmane Mara
Published: November 2021

Craniofacial development including palatogenesis is a complex process which requires an orchestrated and spatiotemporal expression of various genes and factors for proper embryogenesis and organogenesis. One such group of genes essential for craniofacial development is the homeobox genes, transcriptional factors that are commonly associated with congenital abnormalities. Amongst these genes, DLX4, HOXB3, and MSX2 have been recently shown to be involved in the etiology of non-syndromic cleft lip and palate. Hence, we investigated the gene and protein expression of these genes in normal and cleft affected mucosal tissue obtained from 22 children, along with analyzing their role in promoting local-site inflammation using NF-κB. Additionally, we investigated the role of PTX3, which plays a critical role in tissue remodeling and wound repair. We found a residual gene and protein expression of DLX4 in cleft mucosa, although no differences in gene expression levels of HOXB3 and MSX2 were noted. However, a significant increase in protein expression for these genes was noted in the cleft mucosa (p < 0.05), indicating increased cellular proliferation. This was coupled with a significant increase in NF-κB protein expression in cleft mucosa (p < 0.05), highlighting the role of these genes in promotion of pro-inflammatory environment. Finally, no differences in gene expression of PTX3 were noted.
Technology Adoption and Learning-by-Doing: The Case of Bt Cotton Adoption in China
Authors: Tian Guang , Du Xiaoxue , Qiao Fangbin , Trujillo-Barrera Andres
Published: November 2021

Although the benefits of genetically modified (GM) crops have been well documented, how do farmers manage the risk of new technology in the early stages of technology adoption has received less attention. We compare the total factor productivity (TFP) of cotton to other major crops (wheat, rice, and corn) in China between 1990 and 2015, showing that the TFP growth of cotton production is significantly different from all other crops. In particular, the TFP of cotton production increased rapidly in the early 1990s then declined slightly around 2000 and rose again. This pattern coincides with the adoption of Bt cotton process in China. To further investigate the decline of TFP in the early stages of Bt cotton adoption, using aggregate provincial-level data, we implement a TFP decomposition and show that the productivity of GM technology is higher, whereas the technical efficiency of GM technology is lower than that of traditional technologies. Especially, Bt cotton exhibited lower technical efficiency because farmers did not reduce the use of pesticide when they first started to adopt Bt cotton. In addition, we illustrate the occurrence of a learning process as GM technology diffuses throughout China: after farmers gain knowledge of Bt cotton, pesticide use declines and technical efficiency improves.
I Wish I Could Be Like Her/Him! How Self-Congruence Stimulates a Desire to Mimic
Authors: Xiao Li , Saleem Aysha , Tariq Sana Muhammad , Ul Haq Junaid , Guo Mengmeng
Published: November 2021

Influencer marketing acquires customers who follow their favorite celebrities, who have shared beliefs and opinions. This research explores the self-motives and influencer-related factors that lead to influencer congruence. Influenced customers subsequently recommend those influencers to others. No concrete scale of recommendation is available so far. This research also conceptualizes, develops, and validates a scale for recommendations. In this study, 451 respondents answered questions about the influencers they follow. Normality, reliability, and validity were used for hypothesis testing. Results show the positive and direct impacts of all proposed hypotheses. The findings contribute to the literature by presenting a balanced approach to studying two parallel yet integral aspects of influencer marketing: the influencer and the consumer.
The Influence of Natural and Anthropogenic Forcing on Water and Energy Balance and on Photosynthesis
Authors: Song Jaeyoung , Shim Sungbo , Kim Ji-Sun , Lee Jae-Hee , Byun Young-Hwa , Kim Yeon-Hee
Published: November 2021

Land surface processes are rarely studied in Detection and Attribution Model Inter-comparison Project (DAMIP) experiments on climate change. We analyzed a CMIP6 DAMIP historical experiment by using multi-linear regression (MLRM) and analysis of variance methods. We focused on energy and water budgets, including gross primary productivity (GPP). In MLRM, we estimated each forcing’s contribution and identified the role of natural forcing, which is usually ignored. Contributions of the forcing factors varied by region, and high-ranked variables such as net radiation could receive multiple influences. Greenhouse gases (GHG) accelerated energy and water cycles over the global land surface, including evapotranspiration, runoff, GPP, and water-use efficiency. Aerosol (AER) forcing displayed the opposite characteristics, and natural forcing accounted for short-term changes. A long-term analysis of total soil moisture and water budget indicated that as the AER increases, the available water on the global land increases continuously. In the recent past, an increase in net radiation (i.e., a lowered AER) reduced surface moisture and hastened surface water cycle (GHG effect). The results imply that aerosol emission and its counterbalance to GHG are essential to most land surface processes. The exception to this is GPP, which was overdominated by GHG effects.
The Impact of the Construction of Large Reservoirs on the Cultural Landscape: A Case Study of the Shimen Reservoir, Taiwan
Authors: Chen Li-Yu , Hsieh Wen-Zhe , Chou Rung-Jiun
Published: November 2021

Reservoirs are large-scale water facilities with multiple functions, such as water supply, power generation, and tourism. This paper introduces the new community and cultural landscape formed by the indigenous people, engineers, workers who left their homes, and many migrating families at the Shimen Reservoir in Taoyuan, Taiwan, as an example. We analyzed how the community value of reservoir construction contributed to the development of the landscape through fieldwork, document review, and in-depth interviews. First, the new communities created to meet the needs of the immigrants influenced the surrounding environment and shaped a particular lifestyle. Secondly, new immigrants have formed a community consensus, and changes in the diet and natural landscape have promoted local tourism and affected the function of the reservoir. This study concludes that promoting local values through autonomous community action is a sustainable approach to community development. Tourism development with its symbiotic relationship with the reservoir can meet the needs of local socio-economic and cultural development. For sustainable development, a vulnerability study based on the Shimen Reservoir tourism is necessary.
The Content of Polyarenes in Soils of Antarctica: Variability across Landscapes
Authors: Lodygin Evgeny , Abakumov Evgeny , Nizamutdinov Timur
Published: November 2021

Soil cover of the Earth is faced with intensive polychemical contamination. The pathways of the key pollutants are not investigated enough. Thus, the occasional transportation of soils to remote regions could serve as an informative tool for the elaboration of threshold levels of hazardous materials concentration. One of the most striking examples of such transboundary impact was the transfer of soils and grounds to the Antarctic stations Russkaya and Leningradskaya (before the implementation of the Madrid Protocol in 1991). Thus, the complex investigation of qualitative and quantitative composition of polycyclic aromatic hydrocarbons (PAHs) in soils of various genesis (transported from Eurasia and pristine) of Antarctic have been conducted by the method of high-performance liquid chromatography (HPLC) in a gradient elution mode. The variability of PAHs content was evaluated across landscapes: pristine (the Hudson Mountains and the Haswell Archipelago), contaminated soils (stations Myrniy, Druzhnaya 4 and Bellinshausen) and unique samples of former agrosoils transported by fly in-fly of polar staff from St. Petersburg to Antarctic for local polar greenhouses in the Soviet times, when it was not strictly prohibited. The selected objects of study allow us to not only estimate the degree of contamination of Antarctic soils and grounds, but to also make it possible to assess the rate of PAH degradation in Antarctic conditions. Both high molecular and low molecular PAHs are accumulated following intense anthropogenic activity (fossil organic fuel combustion). The PAHs pool is dominated by low molecular weight representatives (naphthalene, phenanthrene, fluoranthene, pyrene). In most cases, the highest concentrations of benz(a)pyrene does not exceed the Russian Threshold Standard rate, which is the strictest one in the world. The statistical analysis of raw data allowed us to conclude that the contamination of pristine soils of Antarctica across variable landscapes is at the very initial stage. However, we recorded extremely high levels of PAHs in the transported former agrosoils. We can assume that our data could be used as background levels for the elaboration of threshold concentrations of the PAHs for such an internationally managed region as Antarctica.
The Expansion Dynamics and Modes of Impervious Surfaces in the Guangdong-Hong Kong-Macau Bay Area, China
Authors: Zhang Shaohua , Yang Kun , Ma Yuling , Li Mingchan
Published: November 2021

Different urban growth patterns have various impact degrees on the urban ecosystem and environment. Impervious surface, a typical artificial construction can be used to reflect urban development. Therefore, this study estimated the spatiotemporal dynamics and expansion patterns of impervious surface area (ISA) in the Guangdong-Hong Kong-Macau (GHM) Bay Area since the establishment of the “Pearl River Delta economic zone” in 1994. Landsat time-series images were used to map the distribution of the ISA based on the combinational biophysical composition index (CBCI) and the bidirectional temporal filtering method (BTFM). The results indicated that the ISA in the GHM Bay Area drastically expanded from 569.23 km2 in 1994 to 10,200.53 km2 in 2016. In addition, the aggregation index (AI) value of the high-density area showed a decreasing trend from 1994 to 2004. However, the value of each landscape metric rapidly increased after 2004. Moreover, the mean ratio of the major axis to the minor axis of standard deviational ellipses from 1994 to 2004 was higher than that from 2005 to 2016. The results of landscape metrics and standard deviational ellipses indicated that the ISA growth pattern changed from edge expanding and leapfrogging to infilling and consolidation, with a turning point in 2004. Moreover, the principal sprawl orientation of the ISA was northwest to southeast before 2004. After 2004, the expansion direction of the ISA was less obvious due to the development pattern of infilling and consolidation. The rapid increase of GDP and population are the driving forces of urban expansion. However, topography and ecological protection policies as the limiting factors, which caused the infilling of the inner city and redevelopment of old urban areas.
Identification and Optimization of the Spatial Structure of Urban and Rural Settlements from a Hierarchical Network Perspective
Authors: Ye Qingqing , Li Jiwei , Kong Xuesong , Zhang Shaokai
Published: November 2021

China has entered a new era of comprehensive promotion of rural revitalization and integrated urban–rural development. The identification and optimization of the spatial structure of urban and rural settlements are of great significance to the realization of rural revitalization and integrated urban–rural development. This study proposes a method framework for identifying and optimizing the spatial structure of urban and rural settlements from a hierarchical network perspective. This framework includes three parts—namely, the identification, analysis, and optimization of the hierarchical network structure of these settlements. The identification of this structure is the foundation of this study. To realize the identification, for each settlement, this study finds and retains its strongest interaction with other settlements which have a stronger capacity for development. This study used Hua County in Henan, China, as an example to verify the method framework. Results showed that the spatial structure of the urban and rural settlements in Hua County identified in this study was complete and continuous, with significant hierarchical and community characteristics. Based on this, a five-level optimization system of these settlements was constructed. This study expands the method used to study the spatial structure of urban and rural settlements from the network perspective and has a theoretical and practical significance for the optimization of the spatial structure of these settlements.
Predictive Factors of Ventilatory Support in Chest Trauma
Authors: Fattori Silvia , Reitano Elisa , Chiara Osvaldo , Cimbanassi Stefania
Published: November 2021

This study aims to define possible predictors of the need of invasive and non-invasive ventilatory support, in addition to predictors of mortality in patients with severe thoracic trauma. Data from 832 patients admitted to our trauma center were collected from 2010 to 2017 and retrospectively analyzed. Demographic data, type of respiratory assistance, chest injuries, trauma scores and outcome were considered. Univariate analysis was performed, and binary logistic regression was applied to significant data. The injury severity score (ISS) and the revised trauma score (RTS) were both found to be predictive factors for invasive ventilation. Multivariate analysis of the anatomical injuries revealed that the association of high-severity thoracic injuries with trauma in other districts is an indicator of the need for orotracheal intubation. From the analysis of physiological parameters, values of systolic blood pressure, lactate, and Glasgow coma scale (GCS) score indicate the need for invasive ventilatory support. Predictive factors for non-invasive ventilation include: RTS, ISS, number of rib fractures and presence of hemothorax. Risk factors for death were: age over 65, the presence of bilateral rib fractures, pulmonary contusion, hemothorax and associated head trauma. In conclusion, the need for invasive ventilatory support in thoracic trauma is associated to the patient’s systemic severity. Non-invasive ventilation is a supportive treatment indicated in physiologically stable patients regardless of the severity of thoracic injury.
Genetic Landscape of Myeloproliferative Neoplasms with an Emphasis on Molecular Diagnostic Laboratory Testing
Authors: Easwar Arti , Siddon Alexa J.
Published: November 2021

Chronic myeloproliferative neoplasms (MPNs) are hematopoietic stem cell neoplasms with driver events including the BCR-ABL1 translocation leading to a diagnosis of chronic myeloid leukemia (CML), or somatic mutations in JAK2, CALR, or MPL resulting in Philadelphia-chromosome-negative MPNs with constitutive activation of the JAK-STAT signaling pathway. In the Philadelphia-chromosome-negative MPNs, modern sequencing panels have identified a vast molecular landscape including additional mutations in genes involved in splicing, signal transduction, DNA methylation, and chromatin modification such as ASXL1, SF3B1, SRSF2, and U2AF1. These additional mutations often influence prognosis in MPNs and therefore are increasingly important for risk stratification. This review focuses on the molecular alterations within the WHO classification of MPNs and laboratory testing used for diagnosis.
Planar EPID-Based Dosimetry for SRS and SRT Patient-Specific QA
Authors: Thongsawad Sangutid , Chanton Tadchapong , Saiyo Nipon , Udee Nuntawat
Published: November 2021

The study’s purpose was to develop and validate Electronic Portal Imaging Device (EPID)-based dosimetry for Stereotactic Radiosurgery (SRS) and Stereotactic Radiation Therapy (SRT) patient-specific Quality Assurance (QA). The co-operation between extended Source-to-Imager Distance (SID) to reduce the saturation effect and simplify the EPID-based dosimetry model was used to perform patient-specific QA in SRS and SRT plans. The four parameters were included for converting the image to dose at depth 10 cm; dose-response linearity with MU, beam profile correction, collimator scatter and water kernel. The model accuracy was validated with 10 SRS/SRT plans. The traditional diode arrays with MapCHECK were also used to perform patient-specific QA for assuring model accuracy. The 150 cm-SID was found a possibility to reduce the saturation effect. The result of model accuracy was found good agreement between our EPID-based dosimetry and TPS calculation with GPR more than 98% for gamma criteria of 3%/3 mm, more than 95% for gamma criteria of 2%/2 mm, and the results related to the measurement with MapCHECK. This study demonstrated the method to perform SRT and SRT patient-specific QA using EPID-based dosimetry in the FFF beam by co-operating between the extended SID that can reduce the saturation effect and estimate the planar dose distribution with the in-house model.
Prochlorperazine Withdraws the Delayed Onset Tonic Activity of Unloaded Rat Soleus Muscle: A Pilot Study
Authors: Kalashnikov Vitaliy E. , Tyganov Sergey A. , Turtikova Olga V. , Kalashnikova Ekaterina P. , Glazova Margarita V. , Mirzoev Timur M. , Shenkman Boris S.
Published: November 2021

A gradual increase in rat soleus muscle electromyographic (EMG) activity is known to occur after 3–4 days of hindlimb suspension/unloading (HS). The physiological significance and mechanisms of such activity of motoneurons under unloading conditions are currently unclear. Since hyperactivity of motoneurons and muscle spasticity after spinal cord injury are associated with KCC2 downregulation, we hypothesized that a decrease in potassium (K+)/chloride (Cl−) co-transporter 2 (KCC2) in motoneurons would be responsible for an increase in soleus muscle EMG activity during HS. We aimed to investigate the effect of prochlorperazine (KCC2 activator) on the electrical activity of rat soleus muscle under HS. Wistar rats were divided into the following groups: (1) vivarium control (C), (2) 7-day HS group (7HS) and (3) 7-day HS group plus intraperitoneal injections of prochlorperazine (10 mg/kg, daily) (7HS + P). Expression of proteins in the motoneurons of the lumbar spinal cord was determined by Western blotting. An electromyogram of the rat soleus muscle was recorded using intramuscular electrodes. KCC2 content after 7-day HS significantly decreased by 34% relative to the control group. HS-induced decrease in KCC2 protein content was prevented by prochlorperazine administration. HS also induced a significant 80% decrease in KCC2 Ser940 phosphorylation; however prochlorperazine did not affect KCC2 phosphorylation. The treatment of the rats with prochlorperazine prevented a HS-induced increase in Na(+)/K(+)/(Cl−) co-transporter 1 (KCC2 antagonist) protein content. In parallel with the restoration of KCC2 content, prochlorperazine administration during HS partially prevented an increase in the soleus muscle tonic EMG activity. Thus, prochlorperazine administration during 7-day HS prevents a decrease in KCC2 protein expression in motoneurons and significantly reduces the level of HS-induced soleus muscle electrical activity.
Vitamin C Intervention for Critical COVID-19: A Pragmatic Review of the Current Level of Evidence
Authors: Holford Patrick , Carr Anitra C. , Zawari Masuma , Vizcaychipi Marcela P.
Published: November 2021

Severe respiratory infections are characterized by elevated inflammation and generation of reactive oxygen species (ROS) which may lead to a decrease in antioxidants such as vitamin C and a higher requirement for the vitamin. Administration of intravenous vitamin C to patients with pneumonia and sepsis appears to decrease the severity of the disease and potentially improve survival rate. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes pneumonia, sepsis and acute respiratory distress syndrome (ARDS) in severe cases, and is referred to as coronavirus disease 2019 (COVID-19). Patients with COVID-19 infection also appear to have depleted vitamin C status and require additional supplementation of vitamin C during the acute phase of the disease. To date there have been 12 vitamin C and COVID-19 trials published, including five randomised controlled trials (RCTs) and seven retrospective cohort studies. The current level of evidence from the RCTs suggests that intravenous vitamin C intervention may improve oxygenation parameters, reduce inflammatory markers, decrease days in hospital and reduce mortality, particularly in the more severely ill patients. High doses of oral vitamin C supplementation may also improve the rate of recovery in less severe cases. No adverse events have been reported in published vitamin C clinical trials in COVID-19 patients. Upcoming findings from larger RCTs will provide additional evidence on vitamin supplementation in COVID-19 patients.
Extracellular ATP Induced S-Phase Cell Cycle Arrest via P2Y Receptor-Activated ERK Signaling in Poorly Differentiated Oral Squamous Cell Carcinoma SAS Cells
Authors: Lau Chia Chih , Aminuddin Amnani , Chan Kok Meng , Paterson Ian C. , Law Lok Mun , Ng Pei Yuen
Published: November 2021

Extracellular ATP in the tumor microenvironment exhibits either pro- or antitumor effect via interaction with P2Y receptors, but the intracellular signaling and functional roles of P2Y receptors in oral squamous cell carcinoma (OSCC) are unclear. We aimed to study the effect of ATP on OSCC cell lines and the potential mechanisms involved. Through GEPIA dataset analysis, high expression levels of mRNA encoding P2Y receptors, the ATP-induced G protein-coupled receptors, were associated with better overall patient survival in head and neck squamous cell carcinoma. qPCR analysis showed that the poorly differentiated OSCC SAS cell line, had higher P2RY1 expression level compared to the well-differentiated H103 and H376 cell lines. Western blotting and flow cytometry analyses revealed that ATP phosphorylated ERK and elevated intracellular calcium signaling in all tested cell lines. A significant S-phase cell cycle arrest was observed in SAS, and preincubation with the MEK inhibitor PD0325901 reversed the ATP-induced S-phase arrest. We further demonstrated that ATP induced a slight reduction in cell count and colony formation yet significant apoptosis in SAS. Overall, we postulate that the ATP-induced S-phase arrest effect in SAS cells may be regulated through P2Y receptor-mediated ERK signaling, thus suggesting a potential antitumor effect of ATP via interaction with its distinct profile of P2Y receptors.
Tribological Behavior of Novel CNTs-Based Lubricant Grease in Steady-State and Fretting Sliding Conditions
Authors: Senatore Adolfo , Hong Haiping , D’Urso Veronica , Younes Hammad
Published: November 2021

The tribological behavior of novel 7.5 wt% carbon nanotube-based lubricant greases in PAO (polyalphaolefin) oil with and without 1.0 wt% MoS2, together with several other commercial greases such as calcium, lithium, were studied. The test results showed a marked reduction of frictional coefficient achieved by the CNTs based grease samples with an average benefit of around 30% compared to conventional greases. The steady state test under 1.00 GPa average contact pressure in a mixed lubrication regime and the fretting test showed the best results in terms of friction reduction obtained by CNTs greases. Steady state tests at higher average contact pressure of 1.67 GPa proved to have a lower friction coefficient for CNTs grease containing MoS2; otherwise CNTs grease without MoS2 showed an average value of CoF comparable to calcium and lithium greases, both in a boundary and a mixed regime. The protection against wear, a considerable decrease (−60%) of reference parameter was measured with CNTs grease with MoS2 (NLGI 2) in comparison with the worst conventional grease and −22% in comparison with the best conventional grease. The data indicated that our novel carbon nanotube greases show superior tribological properties and will have promising applications in the corresponding industry.
Accuracy of the Intra- and Extra-Oral Scanning Technique for Transferring the Intaglio Surface of a Pontic of Provisional Restorations to Definitive Restorations
Authors: Sanda Koma , Yasunami Noriyuki , Okada Maki , Furuhashi Akihiro , Ayukawa Yasunori
Published: November 2021

When taking the final impression for a three-unit fixed partial denture (FPD), the intaglio surface of the pontic of provisional restoration cannot be transferred accurately to that of definitive restoration. The intra- and extra-oral scanning (IEOS) technique, a method for accurately reproducing the submucosal morphology of the superstructure of an implant, has been reported using an intraoral scanner. In the present study, we evaluated the difference between the conventional impression method using impression material and the IEOS technique in reproducing the morphology of the surface of the pontic of a definitive FPD. There was a significant difference in the trueness of the intaglio surface morphology of the pontic between the conventional method and the IEOS technique; however, no significant difference in precision was observed. As a result, the intaglio surface of the pontic of the three-unit FPD could be transferred to definitive restorations more accurately with the IEOS technique than with the conventional method. These results suggest that the IEOS technique can duplicate the intaglio surface of the pontic more reproducibly to the definitive restorations compared with the conventional method.
Modified Mesoporous Carbon Material (Pb-N-CMK-3) Obtained by a Hard-Templating Route, Dicyandiamide Impregnation and Electrochemical Lead Particles Deposition as an Electrode Material for the U(VI) Ultratrace Determination
Authors: Tyszczuk-Rotko Katarzyna , Olchowski Rafał , Kozak Jędrzej , Sekerzh-Zenkovich Olga , Dobrowolski Ryszard
Published: November 2021

In this paper, a dicyandiamide-impregnated mesoporous carbon (N-CMK-3), electrochemically modified in situ with lead film (Pb-N-CMK-3), was tested as an electrode material for U(VI) ultratrace determination. The prepared carbon material was characterized by XRD, SEM-EDX, Raman, FT-IR, XPS analysis and nitrogen sorption measurements. The changes of electrochemical properties of glassy carbon electrodes (GCE) after the N-CMK-3 and Pb-N-CMK-3 modification were studied using CV and EIS methods. The modification of the GCE surface by the N-CMK-3 material and Pb film increases the electroactive area of the electrode and decreases the charge transfer residence and is likely responsible for the electrochemical improvement of the U(VI) analytical signal. Using square-wave adsorptive stripping voltammetry (SWAdSV), two linear calibration ranges extending from 0.05 to 1.0 nM and from 1.0 to 10.0 nM were observed, coupled with the detection and quantification limits of 0.014 and 0.047 nM, respectively. The Pb-N-CMK-3/GCE was successfully applied for U(VI) determination in reference materials (estuarine water SLEW-3 and trace elements in natural water SRM 1640a).
Turning Tool Wear Estimation Based on the Calculated Parameter Values of the Thermodynamic Subsystem of the Cutting System
Authors: Lapshin Victor Petrovich
Published: November 2021

Today, modern metalworking centers are not yet able to reliably assess the degree of wear of the tool used in metal cutting. Despite the fact that a large number of methods for monitoring the service life of the tool have been developed, this issue still remains a difficult task that needs to be solved. Idea: The article proposes a new, previously unused method for estimating the power of a cutting wedge in metalworking. The aim of the study is to develop a method for indirectly estimating the tool wear rate based on a consistent model of intersystem communication that describes the force, thermal and vibration reactions of the cutting process to the shaping movements of the tool. Research methods: The study consists of experiments on a measuring stand and a homemade measuring complex. It also uses the Matlab mathematical software package for processing and graphical interpretation of data obtained during experiments. The results show that the proposed method of estimating the current tool wear is applicable for the interpretation of experimental data. Statistically, the modified Voltaire operator of the second kind models the temperature more accurately; at the peak, this method is three times more accurate than the other.
Seismic Response of Resilient Bridges with SMA-Based Rocking ECC-Reinforced Piers
Authors: Li Xiaogang , Chen Ke , Chen Ji , Li Yi , Yang Dong
Published: November 2021

Post-earthquake investigation shows that numerous reinforced concrete (RC) bridges were demolished because of large residual displacements. Improving the self-centering capability and hence resilience of these bridges located in earthquake-prone regions is essential. In this regard, a resilient bridge system incorporating engineered cementitious composites (ECC) reinforced piers and shape memory alloy (SMA) energy dissipation components, i.e., SMA washers, is proposed to enhance its resilience when subjected to strong earthquakes. This study commences with a detailed introduction of the resilient SMA-washer-based rocking bridge system with ECC-reinforced piers. Subsequently, a constitutive model of the ECC material is implemented into OpenSees and the constitutive model is validated by test data. The working principle and constitutive model of the SMA washers are also introduced. A series of dynamic analysis on the conventional and resilient rocking bridge systems with ECC-reinforced piers under a suite of ground motions at E1 and E2 earthquake levels are conducted. The analysis results indicate that the resilient rocking bridge system with ECC-reinforced piers has superior resilience and damage control capacities over the conventional one.
Analysis of the Electroconsolidation Process of Fine-Dispersed Structures Out of Hot Pressed Al2O3–WC Nanopowders
Authors: Gevorkyan Edwin , Rucki Mirosław , Krzysiak Zbigniew , Chishkala Volodymyr , Zurowski Wojciech , Kucharczyk Wojciech , Barsamyan Voskan , Nerubatskyi Volodymyr , Mazur Tomasz , Morozow Dmitrij , Siemiątkowski Zbigniew , Caban Jacek
Published: November 2021

Fabrication of alumina–tungsten carbide nanocomposite was investigated. Characteristics of the densification and sintering were analyzed considering both the nano-size particle starting powders and the processing stages. Different heating rates were generated during densification and consolidation with a maximal load was applied only after a temperature of 1000 °C was reached. Due to the varying dominance of different physical processes affecting the grains, appropriate heating rates and pressure at different stages ensured that a structure with submicron grains was obtained. With directly applied alternating current, it was found that the proportion Al2O3 (50 wt.%)–WC provided the highest fracture toughness, and a sintering temperature above 1600 °C was found to be disadvantageous. High heating rates and a short sintering time enabled the process to be completed in 12 min, saving energy and time.
Development of Flotation Device for Removing Unburnt Carbon in Fly Ash for Use in Hardened Cementitious Materials
Authors: Lin Hangwei , Takasu Koji , Koyamada Hidehiro , Suyama Hiroki
Published: November 2021

The unburned carbon in fly ash inhibits the performance of concrete. A device using the flotation method to remove unburned carbon in fly ash was developed, and the operating condition of the device was experimentally examined. According to the results, the device was able to remove unburnt carbon from fly ash by using the installed micro bubble nozzles and a whirl-type pump. The removal efficiency of unburnt carbon improved when prior forced stirring was carried out by a concrete mixer for 3 min, and a scavenger was added into the fly ash slurry at a density of about 60 wt%. It has also been confirmed that the method of circulating water is more effective than the method of not circulating water. The elements of the modified fly ash slurry (MFAS) have also been experimentally confirmed as not being too different from untreated fly ash, except for the fact that the content of unburned carbon is reduced. The compressive strength and drying shrinkage characteristics of concrete made with MFAS were investigated. The use of MFAS will reduce the performance of concrete compared to that of ordinary concrete. This shows that in a certain range (15–30%), the influence of MFAS on drying shrinkage is constant. The static elastic modulus and dynamic elastic modulus were also investigated. The above results show that the application of MFAS prepared by the flotation method to concrete is feasible.
Stabilization of the Surface of ZnO Films and Elimination of the Aging Effect
Authors: Abdullin Khabibulla A. , Gabdullin Maratbek T. , Zhumagulov Sultan K. , Ismailova Guzal A. , Gritsenko Lesya V. , Kedruk Yevgeniya Y. , Mirzaeian Mojtaba
Published: November 2021

Zinc oxide is a promising multifunctional material. The practical use of nano- and polycrystalline ZnO devices faces a serious problem of instability of electrical and luminescent characteristics, due to the adsorption of oxygen by the surface during aging. In this paper, the aging effect in ZnO films and nanorod arrays was studied. It was found that ZnO samples demonstrate different behavior of the degradation process, which corresponds to at least two different types of adsorbing surface sites for O2, where O2 adsorption is of a different nature. The first type of surface sites is rapidly depassivated after hydrogen passivation and the aging effect takes place due to these centers. The second type of surface sites has a stable structure after hydrogen passivation and corresponds to HO–ZnO sites. The XPS components of these sites include the Zn2p3/2 peak at 1022.2 ± 0.2 eV and Zn2p1/2 peak at 1045.2 ± 0.2 eV, with a part of the XPS O1s peak at 531.5 ± 0.3 eV. The annealing transforms the first type of site into the second one, and the subsequent short-term plasma treatment in hydrogen results in steady passivation, where the degradation of characteristics is practically reduced to zero.
Recycling of Mechanically Ground Wind Turbine Blades as Filler in Geopolymer Composite
Authors: Pławecka Kinga , Przybyła Jakub , Korniejenko Kinga , Lin Wei-Ting , Cheng An , Łach Michał
Published: November 2021

This paper concerns the recycling of waste material from wind turbine blades. The aim of the research was to determine the possibility of using ground waste material derived from the exploited structures of wind turbines as a filler in geopolymer composites. In order to determine the potential of such a solution, tests were carried out on three different fractions originating from the ground blades of wind turbines, including an analysis of the morphology and chemical composition of particles using SEM and an EDS detector, the analysis of organic and inorganic matter content and tests for multivariate geopolymer composites with the addition of waste material. The compression and flexural strength, density and absorbability tests, among others, were carried out. The composite material made of the geopolymer matrix contained the filler at the level of 5%, 15% and 30% of dry mass. The addition of the filler showed a tendency to decrease the properties of the obtained geopolymer composite. However, it was possible to obtain materials that did not significantly differ in properties from the re-reference sample for the filler content of 5% and 15% of dry mass. As a result of the research, it was found that waste materials from the utilization of used wind power plants can become fillers in geopolymer composites. It was also found that it is possible to increase the strength of the obtained material by lowering the porosity.
Progress in Flexible Electronic Textile for Heating Application: A Critical Review
Authors: Repon Md. Reazuddin , Mikučionienė Daiva
Published: November 2021

Intelligent textiles are predicted to see a ‘surprising’ development in the future. The consequence of this revived interest has been the growth of industrial goods and the improvement of innovative methods for the incorporation of electrical features into textiles materials. Conductive textiles comprise conductive fibres, yarns, fabrics, and finished goods produced using them. Present perspectives to manufacture electrically conductive threads containing conductive substrates, metal wires, metallic yarns, and intrinsically conductive polymers. This analysis concentrates on the latest developments of electro-conductivity in the area of smart textiles and heeds especially to materials and their assembling processes. The aim of this work is to illustrate a potential trade-off between versatility, ergonomics, low energy utilization, integration, and heating properties.
The Influence of Conventional or KOBO Extrusion Process on the Properties of AZ91 (MgAl9Zn1) Alloy
Authors: Długosz Piotr , Bochniak Włodzimierz , Ostachowski Paweł , Molak Rafał , Duarte Guigou Martin , Hebda Marek
Published: November 2021

Designers’ efforts to use the lightest possible materials with very good mechanical properties mean that in recent years magnesium alloys have been increasingly used. It is well-known that the use of various plastic working processes allows achieving even better strength properties of the material, often without significant loss of plastic properties in relation to the properties of products obtained in the casting process. The article presents the results of research on microstructural changes and mechanical properties of the alloy AZ91 (MgAl9Zn1) occurring in samples subjected to conventional plastic deformation and the KOBO method. The obtained results were compared to the properties of reference samples, i.e., cast samples. The article presents the advantage of using the low-temperature KOBO method compared to the high-temperature deformation in a conventional manner. Moreover, it has been shown that the use of KOBO extrusion allows the alloy AZ91 (MgAl9Zn1) to obtain superplasticity properties with an elongation of up to 577% compared to the cast reference sample, which is generally classified as difficult for plastic deformation.
Sputtered Non-Hydrogenated Amorphous Silicon as Alternative Absorber for Silicon Photovoltaic Technology
Authors: Fernández Susana , Gandía J. Javier , Saugar Elías , Gómez-Mancebo Mª Belén , Canteli David , Molpeceres Carlos
Published: November 2021

Non-hydrogenated amorphous-silicon films were deposited on glass substrates by Radio Frequency magnetron sputtering with the aim of being used as precursor of a low-cost absorber to replace the conventional silicon absorber in solar cells. Two Serie of samples were deposited varying the substrate temperature and the working gas pressure, ranged from 0.7 to 4.5 Pa. The first Serie was deposited at room temperature, and the second one, at 325 °C. Relatively high deposition rates above 10 Å/s were reached by varying both deposition temperature and working Argon gas pressure to ensure high manufacturing rates. After deposition, the precursor films were treated with a continuous-wave diode laser to achieve a crystallized material considered as the alternative light absorber. Firstly, the structural and optical properties of non-hydrogenated amorphous silicon precursor films were investigated by Raman spectroscopy, atomic force microscopy, X-ray diffraction, reflectance, and transmittance, respectively. Structural changes were observed in the as-deposited films at room temperature, suggesting an orderly structure within an amorphous silicon matrix; meanwhile, the films deposited at higher temperature pointed out an amorphous structure. Lastly, the effect of the precursor material’s deposition conditions, and the laser parameters used in the crystallization process on the quality and properties of the subsequent crystallized material was evaluated. The results showed a strong influence of deposition conditions used in the amorphous silicon precursor.
Genotoxicity Assessment of Metal-Based Nanocomposites Applied in Drug Delivery
Authors: Cardoso Sara , da Silva Classius F. , Severino Patrícia , Silva Amélia M. , Souto Selma B. , Zielińska Aleksandra , Karczewski Jacek , Souto Eliana B.
Published: November 2021

Nanocomposites as drug delivery systems (e.g., metal nanoparticles) are being exploited for several applications in the biomedical field, from therapeutics to diagnostics. Green nanocomposites stand for nanoparticles of biocompatible, biodegradable and non-toxic profiles. When using metal nanoparticles for drug delivery, the question of how hazardous these “virus-sized particles” can be is posed, due to their nanometer size range with enhanced reactivity compared to their respective bulk counterparts. These structures exhibit a high risk of being internalized by cells and interacting with the genetic material, with the possibility of inducing DNA damage. The Comet Assay, or Single-Cell Gel Electrophoresis (SCGE), stands out for its capacity to detect DNA strand breaks in eukaryotic cells. It has huge potential in the genotoxicity assessment of nanoparticles and respective cells’ interactions. In this review, the Comet assay is described, discussing several examples of its application in the genotoxicity evaluation of nanoparticles commonly administered in a set of routes (oral, skin, inhaled, ocular and parenteral administration). In the nanoparticles boom era, where guidelines for their evaluation are still very limited, it is urgent to ensure their safety, alongside their quality and efficacy. Comet assay or SCGE can be considered an essential tool and a reliable source to achieve a better nanotoxicology assessment of metal nanoparticles used in drug delivery.
Optimal Selection of High-Performance Concrete for Post-Tensioned Girder Bridge Using Advanced Hybrid MCDA Method
Authors: Janowska-Renkas Elżbieta , Jakiel Przemysław , Fabianowski Dariusz , Matyjaszczyk Damian
Published: November 2021

The selection of material solutions is a basic decision-making problem that occurs in engineering issues. It affects the entire life cycle of a building structure, its safe use, maintenance costs, and a need to meet requirements for sustainable development, including recycling. This paper aims at selection of the optimum composition of HPC designed for monolithic girder structures of post-tension bridges. For the analysis, a set of 12 new-generation concretes (HPC) was designed, made, and tested. A full-scope set of evaluation criteria was created and then the optimal alternative was selected. For this purpose, an advanced hybrid algorithm combining EA FAHP (Extent Analysis Fuzzy Analytic Hierarchy Process) and FuzzyTOPSIS (Fuzzy Technique for Order Preference by Similarity to an Ideal Solution) methods was used. The obtained results indicate a possibility for the practical application of the proposed algorithm by decision-making engineering staff. It can also be the basis for further research on application compared to other material and design solutions and, depending on the issue, different combination of aggregated methods.
Adoption of the Wet Surface Treatment Technique for the Improvement of Device Performance of Enhancement-Mode AlGaN/GaN MOSHEMTs for Millimeter-Wave Applications
Authors: Wang Chun , Chen Yu-Chiao , Hsu Heng-Tung , Tsao Yi-Fan , Lin Yueh-Chin , Dee Chang-Fu , Chang Edward-Yi
Published: November 2021

In this work, a low-power plasma oxidation surface treatment followed by Al2O3 gate dielectric deposition technique is adopted to improve device performance of the enhancement-mode (E-mode) AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors (MOSHEMTs) intended for applications at millimeter-wave frequencies. The fabricated device exhibited a threshold voltage (Vth) of 0.13 V and a maximum transconductance (gm) of 484 (mS/mm). At 38 GHz, an output power density of 3.22 W/mm with a power-added efficiency (PAE) of 34.83% were achieved. Such superior performance was mainly attributed to the high-quality Al2O3 layer with a smooth surface which also suppressed the current collapse phenomenon.
Quantitative Strengthening Evaluation of Powder Metallurgy Titanium Alloys with Substitutional Zr and Interstitial O Solutes via Homogenization Heat Treatment
Authors: Kondoh Katsuyoshi , Kariya Shota , Khantachawana Anak , Alhazaa Abdulaziz , Umeda Junko
Published: November 2021

The decomposition behavior of ZrO2 particles and uniform distribution of Zr and O solutes were investigated by employing in situ scanning electron microscope-electron backscatter diffraction (SEM-EBSD) analysis and thermogravimetric-differential thermal analysis (TG-DTA) to optimize the process conditions in preparing Ti-Zr-O alloys from the pre-mixed pure Ti powder and ZrO2 particles. The extruded Ti-Zr-O alloys via homogenization and water-quenching treatment were found to have a uniform distribution of Zr and O solutes in the matrix and also showed a remarkable improvement in the mechanical properties, for example, the yield stress of Ti-3 wt.% ZrO2 sample (1144.5 MPa) is about 2.5 times more than the amount of yield stress of pure Ti (471.4 MPa). Furthermore, the oxygen solid-solution was dominant in the yield stress increment, and the experimental data agreed well with the calculation results estimated using the Hall-Petch equation and Labusch model.
An Experimentally Aided Operational Virtual Prototyping to Obtain the Best Spindle Speed during Face Milling of Large-Size Structures
Authors: Kaliński Krzysztof J. , Galewski Marek A. , Mazur Michał R. , Stawicka-Morawska Natalia
Published: November 2021

The paper presents an original method concerning the problem of vibration reduction in the general case while milling large-size and geometrically complex details with the use of an innovative approach to the selection of spindle speed. A computational model is obtained by applying the so-called operational approach to identify the parameters of the workpiece modal model. Thanks to the experimental modal analysis results, modal subsystem identification was performed and reliable process data for simulation studies were obtained. Next, simulations of the milling process, for successive values of the spindle speed, are repeated until the best vibration state of the workpiece is obtained. For this purpose, the root mean square values of the time plots of vibration displacements are examined. The effectiveness of the approach proposed for reducing vibrations in the process of face milling is verified on the basis of the results of appropriate experimental investigations. The economic profitability of the implementation of the operational technique in the production practice of enterprises dealing with mechanical processing is demonstrated as well.