bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducing Helicopter Vibration Loads by Individual Blade Control with Genetic Algorithm
Authors: Yang Renguo , Gao Yadong , Wang Huaming , Ni Xianping
Published: June 2022

A rotor that can realize individual blade pitch control was designed. This paper focuses on finding the trend of helicopter vibration loads after applying multiple high-order harmonic control. The Glauert inflow model was introduced to calculate the induced velocity of rotor blades in a rotor disk plane, and the Leishman Beddoes (L-B) unsteady dynamic model was employed to calculate the aerodynamic forces of each section of a rotor blade. It was found that the influence of each high-order harmonic control on individual blade vibration load reduction is similar in different advanced ratios. After these calculations, the genetic algorithm was used to calculate the best combination of amplitude and phase of the higher order harmonic under a specific flight state. Under the effect of high harmonic input, the vibration loads of the hub could be reduced by about 65%. These results can be theoretically applied to design control law to reduce helicopter vibration loads.
Multi-Objective Optimization Design for a Novel Parametrized Torque Converter Based on an Integrated CFD Cascade Design System
Authors: Ran Zilin , Ma Wenxing , Wang Kaifeng , Chai Bosen
Published: June 2022

Advanced cascade design theories and methods are crucial to the rapid development of torque converters. Therefore, the study proposed a new parametric design method for a hydrodynamic torque converter cascade. The method is embodied by using a cubic non-uniform rational B-splines (NURBS) open curve and closed curve, respectively, to carry out the parametric design of the unit blade camberline and unit blade thickness distribution, and the curvature of the designed blade curve is continuous. Then, the author developed batch and script files in the Isight platform for a fully automated integrated design of the hydrodynamic torque converter, including cascade parametric modeling, meshing, computational fluid dynamics (CFD) simulation, post-processing, and optimization design. A three-dimensional cascade integrated optimization design system of the hydrodynamic torque converter is established with CFD technology as the bottom layer design, a control file as the middle layer, and an optimization algorithm as the top layer drive. Finally, multi-objective optimization was carried out for the key cascade parameters (camberline peak height). Compared with the original blade, the optimized NURBS blade increased by 7.207% in high-efficiency region width (Gη), and the optimized blade increased by 2.673% in peak efficiency (ηmax) to meet the actual engineering requirements. The new parametric design method of the blade shape and the integrated optimization design system of a three-dimensional cascade of torque converter proposed in this paper significantly reduces the design costs and shortens the design cycle of the torque converter, which will provide a valuable reference for engineers of turbomachinery.
Synchronization of Epidemic Systems with Neumann Boundary Value under Delayed Impulse
Authors: Rao Ruofeng , Lin Zhi , Ai Xiaoquan , Wu Jiarui
Published: June 2022

This paper reports the construction of synchronization criteria for the delayed impulsive epidemic models with reaction–diffusion under the Neumann boundary value. Different from the previous literature, the reaction–diffusion epidemic model with a delayed impulse brings mathematical difficulties to this paper. In fact, due to the existence of second-order partial derivatives in the reaction–diffusion model with a delayed impulse, the methods of first-order ordinary differential equations from the previous literature cannot be effectively applied in this paper. However, with the help of the variational method and an appropriate boundedness assumption, a new synchronization criterion is derived, and its effectiveness is illustrated by numerical examples.
Singularities of Serial Robots: Identification and Distance Computation Using Geometric Algebra
Authors: Zaplana Isiah , Hadfield Hugo , Lasenby Joan
Published: June 2022

The singularities of serial robotic manipulators are those configurations in which the robot loses the ability to move in at least one direction. Hence, their identification is fundamental to enhance the performance of current control and motion planning strategies. While classical approaches entail the computation of the determinant of either a 6×n or n×n matrix for an n-degrees-of-freedom serial robot, this work addresses a novel singularity identification method based on modelling the twists defined by the joint axes of the robot as vectors of the six-dimensional and three-dimensional geometric algebras. In particular, it consists of identifying which configurations cause the exterior product of these twists to vanish. In addition, since rotors represent rotations in geometric algebra, once these singularities have been identified, a distance function is defined in the configuration space C, such that its restriction to the set of singular configurations S allows us to compute the distance of any configuration to a given singularity. This distance function is used to enhance how the singularities are handled in three different scenarios, namely, motion planning, motion control and bilateral teleoperation.
Existence and Multiplicity of Solutions for a Class of Particular Boundary Value Poisson Equations
Authors: Yu Songyue , Yan Baoqiang
Published: June 2022

In this paper, a special class of boundary value problems, −▵u=λuq+ur,inΩ,u>0, inΩ,n·∇u+g(u)u=0,on∂Ω, where 0<q<1<r0 is a parameter. The existence of the solution is verified via sub- and super-solutions method. In addition, the influences of parameters on the minimum solution are also discussed. The second positive solution is obtained by using the variational method.
Dynamical Analysis of Fractional Integro-Differential Equations
Authors: Hassan Taher S. , Odinaev Ismoil , Shah Rasool , Weera Wajaree
Published: June 2022

In this article, we solve fractional Integro differential equations (FIDEs) through a well-known technique known as the Chebyshev Pseudospectral method. In the Caputo manner, the fractional derivative is taken. The main advantage of the proposed technique is that it reduces such types of equations to linear or nonlinear algebraic equations. The acquired results demonstrate the accuracy and reliability of the current approach. The results are compared to those obtained by other approaches and the exact solution. Three test problems were used to demonstrate the effectiveness of the proposed technique. For different fractional orders, the results of the proposed technique are plotted. Plotting absolute error figures and comparing results to some existing solutions reveals the accuracy of the proposed technique. The comparison with the exact solution, hybrid Legendre polynomials, and block-pulse functions approach, Reproducing Kernel Hilbert Space method, Haar wavelet method, and Pseudo-operational matrix method confirm that Chebyshev Pseudospectral method is more accurate and straightforward as compared to other methods.
Estimating the Time Reproduction Number in Kupang City Indonesia, 2016–2020, and Assessing the Effects of Vaccination and Different Wolbachia Strains on Dengue Transmission Dynamics
Authors: Ndii Meksianis Z. , Beay Lazarus Kalvein , Anggriani Nursanti , Nukul Karolina N. , Djahi Bertha S.
Published: June 2022

The use of a vaccine and Wolbachia bacterium have been proposed as new strategies against dengue. However, the performance of Wolbachia in reducing dengue incidence may depend on the Wolbachia strains. Therefore, in this paper, the performance of two Wolbachia strains which are WMel and WAu, in combination with the vaccine, has been assessed by using an age-dependent mathematical model. An effective reproduction number has been calculated using the Extended Kalman Filter (EKF) algorithm. The results revealed that the time reproduction number varies overtime with the highest one being around 2.75. Moreover, it has also found that use of the vaccine and Wolbachia possibly leads to dengue elimination. Furthermore, vaccination on one group only reduces dengue incidence in that group but dengue infection in the other group is still high. Furthermore, the performance of the WAu strain is better than the WMel strain in reducing dengue incidence. However, both strains can still be used for dengue elimination strategies depending on the level of loss of Wolbachia infections in both strains.
Matching Ontologies through Multi-Objective Evolutionary Algorithm with Relevance Matrix
Authors: Zhu Hai , Xue Xingsi , Wang Hongfeng
Published: June 2022

The ultimate goal of semantic web (SW) is to implement mutual collaborations among ontology-based intelligent systems. To this end, it is necessary to integrate those domain-independent and cross-domain ontologies by finding the correspondences between their entities, which is the so-called ontology matching. To improve the quality of ontology alignment, in this work, the ontology matching problem is first defined as a sparse multi-objective optimization problem (SMOOP), and then, a multi-objective evolutionary algorithm with a relevance matrix (MOEA-RM) is proposed to address it. In particular, a relevance matrix (RM) is presented to adaptively measure the relevance of each individual’s genes to the objectives, which is applied in MOEA’s initialization, crossover and mutation to ensure the population’s sparsity and to speed up the the algorithm’s convergence. The experiment verifies the performance of MOEA-RM by comparing it with the state-of-the-art ontology matching techniques, and the experimental results show that MOEA-RM is able to effectively address the ontology matching problem with different heterogeneity characteristics.
Effect of Particle Size Distribution on the Dynamic Mechanical Properties and Fractal Characteristics of Cemented Rock Strata
Authors: Wang Jiajun , Huang Linqi , Li Xibing , Wu Yangchun , Liu Huilin
Published: June 2022

To investigate the dynamic mechanics and post-failure characteristics of fault-cemented rock strata, broken rock particles were reshaped to obtain cemented rock samples with various particle size distributions (PSDs). Split Hopkinson pressure bar (SHPB) dynamic impact tests were performed on the cemented rock samples under different strain rates. The test results show that plastic deformation occurs in the cemented rock sample as a result of its porous structure. Therefore, there is no linear phase in the dynamic stress–strain curves. With an increase in the Talbot index and mixture type, more large particles were contained inside the cemented rock sample, and the dynamic strength gradually increased. A power function can effectively describe the relationship between the strain rate and dynamic strength for various Talbot indices. After dynamic impact, the fragments of the cemented rock samples exhibit evident fractal laws, and the breakage of the samples includes breakage of the original rock particle itself and breakage between the rock particles and cementations. The breakage ratio and fractal dimension both decrease with the increase in the number of mixture type and Talbot index but increase with the increase in strain rate. It is worth noting that the breakage ratio and fractal dimension have a linear relationship regardless of the PSD or strain. The relationship between the dynamic strength and fractal dimension has different response laws for the PSD and strain rate effects. The dynamic strength is negatively linearly related to the fractal dimension under the PSD effect but positively linearly related to the fractal dimension under the strain rate effect. This research work can provide foundation support for investigating the instability mechanism of fault cemented rock strata under dynamic stress.
A Novel Approach Based on Honey Badger Algorithm for Optimal Allocation of Multiple DG and Capacitor in Radial Distribution Networks Considering Power Loss Sensitivity
Authors: Elseify Mohamed A. , Kamel Salah , Abdel-Mawgoud Hussein , Elattar Ehab E.
Published: June 2022

Recently, the integration of distributed generators (DGs) in radial distribution systems (RDS) has been widely evolving due to its sustainability and lack of pollution. This study presents an efficient optimization technique named the honey badger algorithm (HBA) for specifying the optimum size and location of capacitors and different types of DGs to minimize the total active power loss of the network. The Combined Power Loss Sensitivity (CPLS) factor is deployed with the HBA to accelerate the estimation process by specifying the candidate buses for optimal placement of DGs and capacitors in RDS. The performance of the optimization algorithm is demonstrated through the application to the IEEE 69-bus standard RDS with different scenarios: DG Type-I, DG Type-III, and capacitor banks (CBs). Furthermore, the effects of simultaneously integrating single and multiple DG Type-I with DG Type-III are illustrated. The results obtained revealed the effectiveness of the HBA for optimizing the size and location of single and multiple DGs and CBs with a considerable decline in the system’s real power losses. Additionally, the results have been compared with those obtained by other known algorithms.
Collaboration Effect by Co-Authorship on Academic Citation and Social Attention of Research
Authors: Dorta-González Pablo , Dorta-González María Isabel
Published: June 2022

Academic citation and social attention measure different dimensions of the impact of research results. Both measures do not correlate with each other, and they are influenced by many factors. Among these factors are the field of research, the type of access, and co-authorship. In this study, the increase in the impact due to co-authorship in scientific articles disaggregated by field of research and access type, was quantified. For this, the citations and social attention accumulated until the year 2021 by a total of 244,880 research articles published in the year 2018, were analyzed. The data source was Dimensions.ai, and the units of study were research articles in Economics, History and Archaeology, and Mathematics. As the main results, a small proportion of the articles received a large part of the citations and most of the social attention. Both citations and social attention increased, in general, with the number of co-authors. Thus, the greater the number of co-authors, the greater the probability of being cited in academic articles and mentioned on social media. The advantage in citation and social attention due to collaboration is independent of the access type for the publication. Furthermore, although collaboration with an additional co-author is in general positive in terms of citation and social attention, these positive effects reduce as the number of co-authors increases.
Validation and Cultural Adaptation of the Serbian Version of the Pediatric Outcome Data Collection Instrument (PODCI) in Children with Obstetrical Brachial Plexus Lesion
Authors: Stojkovic Jasna , Cirovic Dragana , Petronic Ivana , Stanisavljevic Dejana , Ducic Sinisa , Jovanovic Branislav , Pejanovic Jovanovic Jelena , Filipovic Tamara , Subotic Slobodan , Nikolic Dejan
Published: June 2022

Background and objectives: Pediatric Outcome Data Collection Instrument (PODCI) is among the most described scales developed to evaluate the physical status of children and adolescents with various musculoskeletal disorders. We aimed to translate PODCI from English to Serbian, culturally adopt items and domains, evaluate the temporal stability, internal consistency and the test–retest reliability of PODCISR in children with obstetrical brachial plexus lesion (OBPL), and finally, to test the construct validity of PODCISR against muscular manual test (MMT) Materials and Methods: The study included 48 eligible participants aged between 2 and 10 years with OBPL. The MMT was used to test the construct validity. Results: There were no significant differences (p > 0.05) between test and retest for all PODCISR domains. Correlations for all tested domains with MMT were statistically significant except for biceps muscle and domains II and IV. Cronbach’s alpha value of the Global Functioning Scale was good and equaled 0.838 for test and 0.832 for retest session. Cronbach’s α was more than 0.600 for all PODCISR domains except for Domain II and for Domain IV. The observed Test–Retest ICC for all PODCISR domains scores ranged from 0.899 to 0.996. Conclusion: The Serbian version of PODCI (PODCISR) was successfully translated and transculturally adopted. It has satisfactory temporal stability, construct validity and test–retest reliability as well as relevant internal consistency.
Sacroiliac Screw Placement with Ease: CT-Guided Pelvic Fracture Osteosynthesis in the Elderly
Authors: Kress Hannah , Klein Roman , Pohlemann Tim , Wölfl Christoph Georg
Published: June 2022

Background and Objectives: The number of geriatric patients presenting with fragility fractures of the pelvis is increasing due to ageing Western societies. There are nonoperative and several operative treatment approaches. Many of which cause prolonged hospitalisation, so patients become bedridden and lose mobility and independence. This retrospective study evaluates the postoperative outcome of a computed tomography-guided (CT-guided) minimally invasive approach of sacroiliac screw osteosynthesis. The particular focus is to demonstrate its ease of use, feasibility with the equipment of virtually every hospital and beneficial outcomes to the patients. Materials and Methods: 28 patients (3 men, 25 women, age 80.5 ± 6.54 years) with fragility fractures of the pelvis types II-IV presenting between August 2015 and September 2021 were retrospectively reviewed. The operation was performed using the CT of the radiology department for intraoperative visualization of screw placement. Patients only received screw osteosynthesis of the posterior pelvic ring and cannulated screws underwent cement augmentation. Outcomes measured included demographic data, fracture type, postoperative parameters and complications encountered. The quality of life (QoL) was assessed using the German version of the EQ-5D-3L. Results: The average operation time was 32.4 ± 9.6 min for the unilateral and 50.7 ± 17.4 for the bilateral procedure. There was no significant difference between surgeons operating (p = 0.12). The postoperative CT scans were used to evaluate the outcome and showed only one case of penetration (by 1 mm) of the ventral cortex, which did not require operative revision. No case of major complication was reported. Following surgery, patients were discharged after a median of 4 days (Interquartile range 3–7.5). 53.4% of the patients were discharged home or to rehabilitation. The average score on the visual analogue scale of the EQ-5D-3L evaluating the overall wellbeing was 55.6 (Interquartile range (IQR) 0–60). Conclusions: This study shows that the operative method is safe to use in daily practice, is readily available and causes few complications. It permits immediate postoperative mobilization and adequate pain control. Independence and good quality of life are preserved.
Semi-Quantitative Evaluation of Asymmetricity of Dialysis Membrane Using Forward and Backward Ultrafiltration
Authors: Yamashita Akihiro C. , Kakee Toshiki , Ono Takahisa , Motegi Jun , Yamaguchi Satoru , Sunohara Takashi
Published: June 2022

Performance of the dialysis membrane is strongly dependent upon the physicochemical structure of the membrane. The objective of this study is to devise a new in vitro evaluation technique to quantify the physicochemical structures of the membrane. Three commercial dialyzers with cellulose triacetate (CTA), asymmetric CTA (termed ATA®), and polyether sulfone (PES) membranes (Nipro Co., Osaka, Japan) were employed for investigation. Forward and backward ultrafiltration experiments were performed separately with aqueous vitamin B12 (MW 1355), α-chymotrypsin (MW 25,000), albumin (MW 66,000) and dextran solutions, introducing the test solution inside or outside the hollow fiber (HF), respectively. Sieving coefficients (s.c.) for these solutes were measured under the test solution flow rate of 200 mL/min and the ultrafiltration rate of 10 mL/min at 310 K, according to the guidelines provided by Japanese academic societies. We defined the ratio of s.c. in the backward ultrafiltration to that in the forward ultrafiltration and termed it the index for asymmetricity (IA). The IA values were unity for vitamin B12 and α-chymotrypsin in all three of the dialyzers. The IA values for albumin, however, were 1.0 in CTA, 1.9 in ATA®, and 3.9 in PES membranes, respectively, which corresponded well with the fact that CTA is homogeneous, whereas ATA® and PES are asymmetrical in structure. Moreover, the asymmetricity of ATA® and PES may be different by twofold. This fact was verified in continuous basis by employing dextran solution before and after being fouled with albumin. These findings may contribute to the development of a novel membrane for improved success of dialysis therapy.
An Experimental and Numerical Simulation Study of Single Particle Impact during Detonation Spraying
Authors: Riabinkina Polina A. , Bataev Ivan A. , Batraev Igor S. , Ruktuev Alexey A. , Ulianitsky Vladimir Yu. , Tanaka Shigeru , Emurlaeva Yulia Yu. , Ogneva Tatiana S. , Bataev Vladimir A.
Published: June 2022

A comparison of the numerical simulation and an experimental study of the collision of the particles and the substrate during detonation spraying is presented. The spraying regimes were chosen to provide unmelted, partially melted, and completely molten particles. The numerical simulation was performed using the smoothed particle hydrodynamics (SPH) method with velocity and temperature settings as initial conditions. Good agreement was obtained between the simulation results and the experimental data, making the SPH simulation suitable for analysis of the deformation of particles and the substrate during detonation spraying. Information about the particle’s shape evolution during the collision is presented. An increase in temperature and plastic strain is analyzed at different points of the particle and substrate. Under certain spraying regimes, it is possible to melt a solid particle due to its high-strain-rate deformation, but no melting of the substrate was observed during the simulation.
Structure, Mechanical Properties and Friction Characteristics of the Al-Mg-Sc Alloy Modified by Friction Stir Processing with the Mo Powder Addition
Authors: Kalashnikova Tatiana , Knyazhev Evgeny , Gurianov Denis , Chumaevskii Andrey , Vorontsov Andrey , Kalashnikov Kirill , Teryukalova Natalya , Kolubaev Evgeny
Published: June 2022

In this study, samples of Al-Mg-Sc alloy were investigated after friction stir processing with the addition of Mo powder. Holes were drilled into 5 mm-thick aluminum alloy sheets into which Mo powder was added at percentages of 5, 10, and 15 wt%. The workpieces with different powder contents were then subjected to four passes of friction stir processing. Studies have shown that at least three tool passes are necessary and sufficient for a uniform Mo powder distribution in the stir zone, but the number of required passes is higher with an increase in the Mo content. Due to the temperature specifics of the processing, no intermetallic compounds are formed in the stir zone, and Mo is distributed as separate particles of different sizes. The average ultimate strength of the composite materials after four passes is approximately 387 MPa in the stir zone, and the relative elongation of the material changes from 15 to 24%. The dry sliding friction test showed that the friction coefficient of the material decreases with the addition of 5 wt% Mo, but with a further increase in Mo content, returns to the original material values.
Effect of Smelting Time on Vanadium and Titanium Distribution Behavior and Slag Viscosity in HIsmelt
Authors: Zhang Shushi , Hu Peng , Rao Jiating , Wang Zhenyang , Zong Yanbing , Zhang Jianliang
Published: June 2022

HIsmelt is well suited for smelting vanadium–titanium magnetite due to its flexibility in feedstock selection and tolerance to high viscosity slag, compared with the blast furnace. In this work, the effect of smelting time on the distribution behavior and recovery rates of vanadium and titanium in HIsmelt smelting of vanadium–titanium magnetite was investigated by experiment for the first time. The relationship between slag viscosity and temperature at different smelting times was further revealed by thermodynamic calculations. The experimental results show that extending the smelting time increases the FeO content in the slag, the LV rose from 0.66 to 5.02, the LTi declined from 206.90 to 114.86, the shorter smelting time is favorable for increasing the recovery ratio of vanadium and titanium in metal and slag. In addition, slag viscosity decreases with increasing smelting time. The precipitation of high melting point titania spinel and CaTiO3 phases is responsible for the significant increase in slag viscosity at 1300 °C.
Toward Suppressing Oil Backflow Based on a Combined Driving Waveform for Electrowetting Displays
Authors: Long Zhengxing , Yi Zichuan , Zhang Hu , Lv Jinpu , Liu Liming , Chi Feng , Shui Lingling , Zhang Chongfu
Published: June 2022

Electrowetting display (EWD) is a new type of paper-like reflective display based on colored oil, which has gradually become one of the most potential electronic papers with low power consumption, fast response, and full color. However, oil backflow can occur in EWDs, which makes it difficult to maintain a stable aperture ratio. In order to improve the stability of the aperture ratio of EWDs, a new driving waveform was proposed based on analyzing the phenomenon of oil backflow. The driving waveform was composed of a shrinking stage and a driving stage. Firstly, a threshold voltage of oil splitting was calculated by analyzing the luminance curve of EWDs, which were driven by different direct current (DC) voltages. Then, an exponential function waveform, which increased from the threshold voltage, was applied to suppress oil splitting. Finally, a periodic signal combined with a reset signal with a DC signal was applied during the driving stage to maintain a stable aperture ratio display. Experimental results showed that the charge trapping effect could be effectively prevented by the proposed driving waveform. Compared with an exponential function waveform, the average luminance value was increased by 28.29%, and the grayscale stability was increased by 13.76%. Compared to a linear function waveform, the aperture ratio was increased by 10.44% and the response time was reduced by 20.27%.
Development of Droplet Digital PCR Assay for Detection of Seed-Borne Burkholderia glumae and B. gladioli Causing Bacterial Panicle Blight Disease of Rice
Authors: Zhang Jiannan , Luo Jinyan , Chen Lei , Ahmed Temoor , Alotaibi Saqer S. , Wang Yanli , Sun Guochang , Li Bin , An Qianli
Published: June 2022

Bacterial panicle blight of rice or bacterial grain rot of rice is a worldwide rice disease. Burkholderia glumae and B. gladioli are the causal agents. The early and accurate detection of seed-borne B. glumae and B. gladioli is critical for domestic and international quarantine and effective control of the disease. Here, genomic analyses revealed that B. gladioli contains five phylogroups and the BG1 primer pair designed to target the 3’-end sequence of a gene encoding a Rhs family protein is specific to B. glumae and two phylogroups within B. gladioli. Using the BG1 primer pair, a 138-bp DNA fragment was amplified only from the tested panicle blight pathogens B. glumae and B. gladioli. An EvaGreen droplet digital PCR (dPCR) assay on detection and quantification of the two pathogens was developed from a SYBR Green real-time quantitative PCR (qPCR). The detection limits of the EvaGreen droplet dPCR on the two pathogens were identical at 2 × 103 colony forming units (CFU)∙mL−1 from bacterial suspensions and 2 × 102 CFU∙seed−1 from rice seeds. The EvaGreen droplet dPCR assay showed 10-fold detection sensitivity of the SYBR Green qPCR and could detect a single copy of the target gene in a 20-μL assay. Together, the SYBR Green qPCR assay allows for routine high-throughput detection of the panicle blight pathogens and the EvaGreen droplet dPCR assay provides a high-sensitive and high-accurate diagnostic method for quarantine of the pathogens.
Enhancing Biocide Efficacy: Targeting Extracellular DNA for Marine Biofilm Disruption
Authors: Tuck Benjamin , Watkin Elizabeth , Somers Anthony , Forsyth Maria , Machuca Laura L.
Published: June 2022

Biofilm formation is a global health, safety and economic concern. The extracellular composition of deleterious multispecies biofilms remains uncanvassed, leading to an absence of targeted biofilm mitigation strategies. Besides economic incentives, drive also exists from industry and research to develop and apply environmentally sustainable chemical treatments (biocides); especially in engineered systems associated with the marine environment. Recently, extracellular DNA (eDNA) was implicated as a critical structural polymer in marine biofilms. Additionally, an environmentally sustainable, multi-functional biocide was also introduced to manage corrosion and biofilm formation. To anticipate biofilm tolerance acquisition to chemical treatments and reduce biocide application quantities, the present research investigated eDNA as a target for biofilm dispersal and potential enhancement of biocide function. Results indicate that mature biofilm viability can be reduced by two-fold using reduced concentrations of the biocide alone (1 mM instead of the recommended 10 mM). Importantly, through the incorporation of an eDNA degradation stage, biocide function could be enhanced by a further ~90% (one further log reduction in viability). Biofilm architecture analysis post-treatment revealed that endonuclease targeting of the matrix allowed greater biocide penetration, leading to the observed viability reduction. Biofilm matrix eDNA is a promising target for biofilm dispersal and antimicrobial enhancement in clinical and engineered systems.
Modeling of Brine/CO2/Mineral Wettability Using Gene Expression Programming (GEP): Application to Carbon Geo-Sequestration
Authors: Abdi Jafar , Amar Menad Nait , Hadipoor Masoud , Gentzis Thomas , Hemmati-Sarapardeh Abdolhossein , Ostadhassan Mehdi
Published: June 2022

Carbon geo-sequestration (CGS), as a well-known procedure, is employed to reduce/store greenhouse gases. Wettability behavior is one of the important parameters in the geological CO2 sequestration process. Few models have been reported for characterizing the contact angle of the brine/CO2/mineral system at different environmental conditions. In this study, a smart machine learning model, namely Gene Expression Programming (GEP), was implemented to model the wettability behavior in a ternary system of CO2, brine, and mineral under different operating conditions, including salinity, pressure, and temperature. The presented models provided an accurate estimation for the receding, static, and advancing contact angles of brine/CO2 on various minerals, such as calcite, feldspar, mica, and quartz. A total of 630 experimental data points were utilized for establishing the correlations. Both statistical evaluation and graphical analyses were performed to show the reliability and performance of the developed models. The results showed that the implemented GEP model accurately predicted the wettability behavior under various operating conditions and a few data points were detected as probably doubtful. The average absolute percent relative error (AAPRE) of the models proposed for calcite, feldspar, mica, and quartz were obtained as 5.66%, 1.56%, 14.44%, and 13.93%, respectively, which confirm the accurate performance of the GEP algorithm. Finally, the investigation of sensitivity analysis indicated that salinity and pressure had the utmost influence on contact angles of brine/CO2 on a range of different minerals. In addition, the effect of the accurate estimation of wettability on CO2 column height for CO2 sequestration was illustrated. According to the impact of wettability on the residual and structural trapping mechanisms during the geo-sequestration of the carbon process, the outcomes of the GEP model can be beneficial for the precise prediction of the capacity of these mechanisms.
Genetic Association between Granites and Mineralization at the Gindi Akwati Cassiterite–Sulfide Deposit, North-Central Nigeria: Insights from Mineralogy, Fluid Inclusions, and Sulfur Isotopes
Authors: Amuda Abdulgafar Kayode , Li Shuang , Yang Xiaoyong , Cao Jingya , Faisal Mohamed
Published: June 2022

The cassiterite–sulfide mineralization occurs within quartz veins and greisenized Precambrian Older Granite around the Gindi Akwati region at the Ropp complex’s western boundary, north-central Nigeria. The intrusion of Jurassic Younger granite porphyry sheared the marginal parts of the Older Granite and the mylonitized zone created pathways for fluids that escaped during the late-stage consolidation of Jurassic biotite granite. The biotite granites are highly differentiated (K/Rb < 200), peraluminous (A/CNK > 1), high-K, and have high Sn concentrations (average = 117 ppm). The intrusion of Jurassic granite porphyry forced Older Granite interaction with ore-bearing fluid that escaped from Jurassic biotite granite under low oxygen fugacity at or below the NNO buffer. The above fluid–rock interaction caused mass changes in host granite during greisenization and redistributed ores in the vicinity of the shears. This suggests that chloride ions take the form of significant complex-forming ligands and efficiently sequestrate, transport, and deposit ore metals (Sn, Zn, Fe, and Cu) locally within the greisenized granites and quartz veins. The redox potential of the ores probably gave a false impression of metal zoning with a relatively higher abundance of the oxide ore than the sulfides at the surface. The alteration mineralogy (quartz-, topaz-, lepidolite-, and fluorite-bearing assemblages) coupled with S isotope and fluid inclusion systematic data suggests the hydrothermal history of “greisens” and veins started with hot (homogenization temperature ≥300 °C), low to moderate salinity (average = 4.08 wt. % NaCl), low density (≤0.6 g/cm3) fluids and ≥ 200 bar trapping pressure. The sulfide isotopic composition (δ34SV-CDT = −1.30 to + 0.87 ‰) is very similar to typical magmatic fluids, indicating late-magmatic to early post-magmatic models of mineralization related to the anorogenic granite intrusions.
Fatty Acid Profile and Antioxidant Capacity of Dabai (Canarium odontophyllum L.): Effect of Origin and Fruit Component
Authors: Salleh Shanti Faridah , Ajibola Olaide Olawunmi , Nolasco-Hipolito Crilio , Husaini Ahmad , Zarrabal-Octavio Carvajal , Lihan Samuel , Adeyinka Gbadebo Clement , Rosli Firdaus R. , Ahmed Idris Adewale , Zayed Mohamed Zaky , Saat Rosmawati
Published: June 2022

In the present work, the influence of geographical location on the fatty acid profiles, antioxidant potential, as well as cytotoxicity of edible dabai fruit fractions (kernel, skin, and pulp) were analyzed. The fatty acid profiles were determined by Gas Chromatography (GC), and the antioxidant activity was quantified with free 2,2-diphenyl-1-picr/ylhdrazyl, while the cytotoxicity was assessed by the brine shrimp lethality test. The results showed that the samples from Sibu, Serian, and Kapit geographical locations had a high content of the saturated fatty acids, ranging from 46.63% to 53.31% in the three fractions. The highest mono-saturated fatty acids (MUFA) content was found in Sibu. Serian and Kapit kernel fractions MUFA, however, ranged from 21.2% to 45.91%. No fatty acid composition was detected in Bentong and Kanowit. The fatty acid composition and DPPH free radical scavenging antioxidant activity of dabai were statistically independent using a multivariate analysis in different localities in Malaysia. The skin fraction had a more appreciable antioxidant potential and toxicity level than the pulp and kernel fractions. The highest antioxidant activity (EC50 198.76 ± 1.06 µg/mL) with an LC50 value of 1387.22 µg/mL was obtained from the Sibu skin fraction. Therefore, the fatty acid composition, antioxidant, as well as cytotoxicity analyses of the extracts from different localities indicated that “geographical location” remarkably influenced fatty acid composition, antioxidant activity, and toxicity.
In Vitro Evaluation of Curcumin Encapsulation in Gum Arabic Dispersions under Different Environments
Authors: Hudiyanti Dwi , Al Khafiz Muhammad Fuad , Anam Khairul , Siahaan Parsaoran , Christa Sherllyn Meida
Published: June 2022

Biopolymers, especially polysaccharides (e.g., gum Arabic), are widely applied as drug carriers in drug delivery systems due to their advantages. Curcumin, with high antioxidant ability but limited solubility and bioavailability in the body, can be encapsulated in gum Arabic to improve its solubility and bioavailability. When curcumin is encapsulated in gum Arabic, it is essential to understand how it works in various conditions. As a result, in Simulated Intestinal Fluid and Simulated Gastric Fluid conditions, we investigated the potential of gum Arabic as the drug carrier of curcumin. This study was conducted by varying the gum Arabic concentrations, i.e., 5, 10, 15, 20, 30, and 40%, to encapsulate 0.1 mg/mL of curcumin. Under both conditions, the greater the gum Arabic concentration, the greater the encapsulation efficiency and antioxidant activity of curcumin, but the worse the gum Arabic loading capacity. To achieve excellent encapsulation efficiency, loading capacity, and antioxidant activity, the data advises that 10% is the best feasible gum Arabic concentration. Regarding the antioxidant activity of curcumin, the findings imply that a high concentration of gum Arabic was effective, and the Simulated Intestinal Fluid brought an excellent surrounding compared to the Simulated Gastric Fluid solution. Moreover, the gum Arabic releases curcumin faster in the Simulated Gastric Fluid condition.
The Quantitative Case-by-Case Analyses of the Socio-Emotional Outcomes of Children with ASD in Robot-Assisted Autism Therapy
Authors: Telisheva Zhansaule , Amirova Aida , Rakhymbayeva Nazerke , Zhanatkyzy Aida , Sandygulova Anara
Published: June 2022

With its focus on robot-assisted autism therapy, this paper presents case-by-case analyses of socio-emotional outcomes of 34 children aged 3–12 years old, with different cases of Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). We grouped children by the following characteristics: ASD alone (n = 22), ASD+ADHD (n = 12), verbal (n = 11), non-verbal (n = 23), low-functioning autism (n = 24), and high-functioning autism (n = 10). This paper provides a series of separate quantitative analyses across the first and last sessions, adaptive and non-adaptive sessions, and parent and no-parent sessions, to present child experiences with the NAO robot, during play-based activities. The results suggest that robots are able to interact with children in social ways and influence their social behaviors over time. Each child with ASD is a unique case and needs an individualized approach to practice and learn social skills with the robot. We, finally, present specific child–robot intricacies that affect how children engage and learn over time as well as across different sessions.
Self-Adaptive Flask-like Nanomotors Based on Fe3O4 Nanoparticles to a Physiological pH
Authors: Gao Tianyu , Lin Jinwei , Xu Leilei , Guan Jianguo
Published: June 2022

In living bodies, pH values, which are precisely regulated and closely associated with diseased cells, can act as an efficient biologically intrinsic indicator for future intelligent biomedicine microsystems. In this work, we have developed flask-like carbonaceous nanomotors (FCNMs), via loading Fe3O4 nanoparticles (NPs) into a cavity, which exhibit a self-adaptive feature to a specific physiological pH by virtue of the pH-dependent dual enzyme-like activities of Fe3O4 NPs. Specifically, the peroxidase-like activity of Fe3O4 NPs in an acidic pH range, and the catalase-like activity in a near neutral and alkaline pH range, determine the products in the motion system (•OH, ions and O2), whose diffusions from the inner to the outside of the flask result in fluid movement providing the driving force for the movement of the FCNMs. Correspondingly, changes of the product concentrations and species in the physiological pH range (4.4–7.4) result, firstly, in velocity decrease and, then, with increase in pH, increase of the FCNMs occurs. Thanks to the non-linear velocity responsiveness, the FCNMs show intriguing pH taxis towards 6.8 (generally corresponding to the physiological pH in tumor microenvironments), where a maximum velocity appears. Furthermore, the superparamagnetic feature of the Fe3O4 NPs simultaneously endows the FCNMs with the abilities to be magnetic-oriented and easily separated. This work could significantly increase the possibility of nanomotors for targeted therapy of tumors and next-generation biotechnological applications.
Microwave-Assisted Solvothermal Synthesis of Mo-Doped TiO2 with Exceptional Textural Properties and Superior Adsorption Kinetics
Authors: Ahmad Yahia H. , Abu Hatab Aymen S. , Mohamed Assem T. , Al-Kuwari Mohammed S. , Aljaber Amina S. , Al-Qaradawi Siham Y.
Published: June 2022

Assigned to their outstanding physicochemical properties, TiO2-based materials have been studied in various applications. Herein, TiO2 doped with different Mo contents (Mo-TiO2) was synthesized via a microwave-assisted solvothermal approach. This was achieved using titanium (IV) butoxide and molybdenum (III) chloride as a precursor and dodecylamine as a surface directing agent. The uniform effective heating delivered by microwave heating reduced the reaction time to less than 30 min, representing several orders of magnitude lower than conventional heating methods. The average particle size ranged between 9.7 and 27.5 nm and it decreased with increasing the Mo content. Furthermore, Mo-TiO2 revealed mesoporous architectures with a high surface area ranging between 170 and 260 m2 g−1, which is superior compared to previously reported Mo-doped TiO2. The performance of Mo-TiO2 was evaluated towards the adsorption of Rhodamine B (RhB). In contrast to TiO2, which revealed negligible adsorption for RhB, Mo-doped samples depicted rapid adsorption for RhB, with a rate that increased with the increase in Mo content. Additionally, Mo-TiO2 expressed enhanced adsorption kinetics for RhB compared to state-of-the-art adsorbents. The introduced synthesis procedure holds a grand promise for the versatile synthesis of metal-doped TiO2 nanostructures with outstanding physicochemical properties.
Tobacco Waste Liquid-Based Organic Fertilizer Particle for Controlled-Release Fulvic Acid and Immobilization of Heavy Metals in Soil
Authors: Wang Dongfang , Li Jiangshan , Yao Xia , Wu Qingchuan , Zhang Jing , Ye Jinghong , Xu He , Wu Zhengyan , Cai Dongqing
Published: June 2022

Every year, a large amount of tobacco waste liquid (TWL) is discharged into the environment, resulting in serious pollution for the environment. In this work, a TWL-based particle (OACT) was fabricated by CaO, attapulgite (ATP), and TWL, and, then, OACT was coated by amino silicon oil (ASO) to form OACT@ASO. Therein, OACT@ASO had high controlled-release ability for fulvic acid (FA), because of the nanonetworks structure for ATP and the high content of FA in TWL. The release ratio (RR) of FA from OACT@ASO reached 94% at 75 h in deionized water, and 23% at 32 d in silica sand. Furthermore, the release mechanism of FA from OACT@ASO was consistent with the First-order law. Additionally, OACT@ASO also possessed high immobilization capacity for Cu(II), Cd(II), and Pb(II) (CCP) in soil. Notably, a pot experiment indicated that OACT@ASO could facilitate the growth of pakchoi seedlings and decrease the absorption of CCP by pakchoi seedlings. Thus, this study provides a new kind of organic fertilizer which could not only release FA, but also immobilize CCP in soil.
Silver Nanoparticles Containing Fucoidan Synthesized by Green Method Have Anti-Trypanosoma cruzi Activity
Authors: Souza Adriana Oliveira , Oliveira Johny Wysllas de Freitas , Moreno Claudia Jéssica Gonsalves , de Medeiros Mayra Jane Campos , Fernandes-Negreiros Marília Medeiros , Souza Flavia Roberta Monteiro , Pontes Daniel Lima , Silva Marcelo Sousa , Rocha Hugo Alexandre Oliveira
Published: June 2022

The brown seaweed Spatoglossum schröederi synthesizes three bioactive fucoidans, the most abundant of which is fucan A. This fucoidan was extracted and its identity was confirmed by chemical analysis, Fourier-transform infrared spectroscopy (FTIR), and agarose gel electrophoresis. Thereafter, silver nanoparticles containing fucan A (AgFuc) were produced using an environmentally friendly synthesis method. AgFuc synthesis was analyzed via UV–vis spectroscopy and FTIR, which confirmed the presence of both silver and fucan A in the AgFuc product. Dynamic light scattering (DLS), X-ray diffraction, scanning electron microscopy, and atomic force microscopy revealed that the AgFuc particles were ~180.0 nm in size and spherical in shape. DLS further demonstrated that AgFuc was stable for five months. Coupled plasma optical emission spectrometry showed that the AgFuc particles contained 5% silver and 95% sugar. AgFuc was shown to be more effective in inhibiting the ability of parasites to reduce MTT than fucan A or silver, regardless of treatment time. In addition, AgFuc induced the death of ~60% of parasites by necrosis and ~17% by apoptosis. Therefore, AgFuc induces damage to the parasites’ mitochondria, which suggests that it is an anti-Trypanosoma cruzi agent. This is the first study to analyze silver nanoparticles containing fucan as an anti-Trypanosoma cruzi agent. Our data indicate that AgFuc nanoparticles have potential therapeutic applications, which should be determined via preclinical in vitro and in vivo studies.
Lubrication Performances of Polyalkylene Glycols at Steel Interface under External Electric Fields
Authors: Ge Xiangyu , Wu Xiaodong , Shi Qiuyu , Wang Wenzhong
Published: June 2022

This work studied the lubrication performances of polyalkylene glycols, which are insulating oils, at the steel interface under external electric fields. The results show that external electric fields greatly affect the lubrication performances of polyalkylene glycols, and there is an optimal voltage (−1.0 V) for the improvement in friction reduction performance. The surface analysis and experiment results indicate that the polyalkylene glycol adsorption film and the reduction in the amount of FexOy and FeOOH in the tribochemical film contribute to improved friction performance under the negative voltage condition. This work proves that the lubrication performances of insulating oils can be affected by external electric fields as well. A lubrication model was proposed, hoping to provide a basic understanding of the lubrication mechanisms of ether-bond-containing insulating oils in the electric environment.