bluuebunny/crossref_metadata_2025 huggingface dataset:
Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering
Authors: Bódis Eszter , Jakab Miklós , Bán Krisztián , Károly Zoltán
Published: March 2022

We studied the fabrication of functionally graded Al2O3–CeO2-stabilized-ZrO2 (CTZ) ceramics by spark plasma sintering. The ceramic composite exhibits a gradual change in terms of composition and porosity in the axial direction. The composition gradient was created by layering starting powders with different Al2O3 to CTZ ratios, whereas the porosity gradient was established with a large temperature difference, which was induced by an asymmetric graphite tool configuration during sintering. SEM investigations confirmed the development of a porosity gradient from the top toward the bottom side of the Al2O3–CTZ ceramic and the relative pore volume distributed in a wide range from 0.02 to 100 µm for the samples sintered in asymmetric configuration (ASY), while for the reference samples (STD), the size of pores was limited in the nanometer scale. The microhardness test exhibited a gradual change along the axis of the ASY samples, reaching 10 GPa difference between the two opposite sides of the Al2O3–CTZ ceramics without any sign of delamination or cracks between the layers. The flexural strength of the samples for both series showed an increasing tendency with higher sintering temperatures. However, the ASY samples achieved higher strength due to their lower total porosity and the newly formed elongated CeAl11O18 particles.
Statistical Methods for Modeling the Compressive Strength of Geopolymer Mortar
Authors: Ahmed Hemn Unis , Abdalla Aso A. , Mohammed Ahmed S. , Mohammed Azad A. , Mosavi Amir
Published: March 2022

In recent years, geopolymer has been developed as an alternative to Portland cement (PC) because of the significant carbon dioxide emissions produced by the cement manufacturing industry. A wide range of source binder materials has been used to prepare geopolymers; however, fly ash (FA) is the most used binder material for creating geopolymer concrete due to its low cost, wide availability, and increased potential for geopolymer preparation. In this paper, 247 experimental datasets were obtained from the literature to develop multiscale models to predict fly-ash-based geopolymer mortar compressive strength (CS). In the modeling process, thirteen different input model parameters were considered to estimate the CS of fly-ash-based geopolymer mortar. The collected data contained various mix proportions and different curing ages (1 to 28 days), as well as different curing temperatures. The CS of all types of cementitious composites, including geopolymer mortars, is one of the most important properties; thus, developing a credible model for forecasting CS has become a priority. Therefore, in this study, three different models, namely, linear regression (LR), multinominal logistic regression (MLR), and nonlinear regression (NLR) were developed to predict the CS of geopolymer mortar. The proposed models were then evaluated using different statistical assessments, including the coefficient of determination (R2), root mean squared error (RMSE), scatter index (SI), objective function value (OBJ), and mean absolute error (MAE). It was found that the NLR model performed better than the LR and MLR models. For the NLR model, R2, RMSE, SI, and OBJ were 0.933, 4.294 MPa, 0.138, 4.209, respectively. The SI value of NLR was 44 and 41% lower than the LR and MLR models’ SI values, respectively. From the sensitivity analysis result, the most effective parameters for predicting CS of geopolymer mortar were the SiO2 percentage of the FA and the alkaline liquid-to-binder ratio of the mixture.
Use of Fumed Silica Nanostructured Additives in Selective Laser Melting and Fabrication of Steel Matrix Nanocomposites
Authors: Koh Hwee Kang , Moo James Guo Sheng , Sing Swee Leong , Yeong Wai Yee
Published: March 2022

The advancement of additive manufacturing (AM) for metal matrix nanocomposites (MMNCs) is gaining enormous attention due to their potential improvement of physical and mechanical performance. When using nanostructured additives as reinforcements in 3D printed metal composites and with the aid of selective laser melting (SLM), the mechanical properties of the composites can be tailored. The nanostructured additive AEROSIL® fumed silica is both cost-effective and beneficial in the production of MMNCs using SLM. In this study, both hydrophobic and hydrophilic fumed silicas were shown to successfully achieve homogenous blends with commercial 316L stainless steel powder. The powder blends, which exhibited better flow, were then used to fabricate samples using SLM. The samples’ microstructure demonstrated that smaller grains were present in the composites, resulting in improvements in mechanical properties by grain refinement compared to those of 316L stainless steel samples.
Special Issue: Characterization of Innovative Asphalt Materials for Use in Pavement Design and Analysis
Authors: Ferrotti Gilda , Graziani Andrea
Published: March 2022

The development of innovative and sustainable materials for use in asphalt pavement applications has received increasing attention over the past 20 years, also thanks to the growing interest in the circular economy approach, which is replacing the linear one [...]
Fire-Exposed Fly-Ash-Based Geopolymer Concrete: Effects of Burning Temperature on Mechanical and Microstructural Properties
Authors: Razak Siti Nooriza Abd , Shafiq Nasir , Guillaumat Laurent , Farhan Syed Ahmad , Lohana Vicky Kumar
Published: March 2022

Geopolymer concrete possesses superior fire resistance compared to ordinary Portland cement (OPC)-based concrete; however, there are concerns regarding its vulnerability when exposed to real fire events. In the present study, the fire resistance of fly-ash-based geopolymer concrete was evaluated relative to that of OPC-based concrete. Concrete specimens of standard strength grades of 20, 40, and 60 MPa were exposed to fire at 500 and 1200 °C for 2 h to simulate real fire events. Visual observation was performed, mass loss and residual compressive strength were measured, and scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) analyses were conducted. OPC-based concrete suffered major cracks accompanied with spalling for the high-strength specimen, while geopolymer concrete experienced minor cracks with no spalling. Mass losses of the geopolymer concrete—of 1.69% and 4%, after the exposure to fire at 500 and 1200 °C, respectively—were lower than those of the OPC-based concrete. More than 50% of the residual compressive strength for low- and medium-strength geopolymer concrete, after the exposure to fire at 1200 °C, was maintained. After the exposure to fire at 500 °C, the residual compressive strength of the geopolymer concrete increased from 13 to 45%, while the OPC-based concrete was not able to sustain its compressive strength. SEM images showed that the matrix of the geopolymer concrete, after the exposure to fire, was denser than that of the OPC-based concrete, while the FTIR spectra of the geopolymer concrete showed a minor shift in wavelength. Hence, our findings indicate that fly-ash-based geopolymer concrete has an excellent fire resistance as compared to OPC-based concrete.
Low-Temperature Cu/SiO2 Hybrid Bonding with Low Contact Resistance Using (111)-Oriented Cu Surfaces
Authors: Ong Jia-Juen , Chiu Wei-Lan , Lee Ou-Hsiang , Chiang Chia-Wen , Chang Hsiang-Hung , Wang Chin-Hung , Shie Kai-Cheng , Yang Shih-Chi , Tran Dinh-Phuc , Tu King-Ning , Chen Chih
Published: March 2022

We adopted (111)-oriented Cu with high surface diffusivity to achieve low-temperature and low-pressure Cu/SiO2 hybrid bonding. Electroplating was employed to fabricate arrays of Cu vias with 78% (111) surface grains. The bonding temperature can be lowered to 200 °C, and the pressure is as low as 1.06 MPa. The bonding process can be accomplished by a 12-inch wafer-to-wafer scheme. The measured specific contact resistance is 1.2 × 10−9 Ω·cm2, which is the lowest value reported in related literature for Cu-Cu joints bonded below 300 °C. The joints possess excellent thermal stability up to 375 °C. The bonding mechanism is also presented to provide more understanding on hybrid bonding.
Investigation of the Oxidation Behavior of Cr20Mn17Fe18Ta23W22 and Microdefects Evolution Induced by Hydrogen Ions before and after Oxidation
Authors: Wu Bao-Zhen , Zhu Te , Cao Xing-Zhong , Yang Zhao-Ming , Zhang Kun , Gou Fu-Jun , Wang Yuan
Published: March 2022

The oxidation behavior of body-centered cubic (bcc) structure Cr20Mn17Fe18Ta23W22 refractory high-entropy alloy (RHEA) and the microdefects induced by hydrogen ions before and after oxidation were investigated. The results revealed that compared with oxidizing Cr20Mn17Fe18Ta23W22 at 800 °C (6.7 °C/min) for 4 h (ST3, Ar:O2 = 3:1), the heating procedure of oxidizing Cr20Mn17Fe18Ta23W22 at 300 °C (6 °C/min) for 2 h and then increased to 800 °C (5 °C/min) for 4 h is more conducive to the production of oxides without spalling on the surface, i.e., HT1 (Ar:O2 = 1:1), HT2 (Ar:O2 = 2:1) and HT3 (Ar:O2 = 3:1) samples. The oxidation of Cr20Mn17Fe18Ta23W22 RHEA is mainly controlled by the diffusion of cations instead of affinities with O. Additionally, HT1 and HT3 samples irradiated with a fluence of 3.9 × 1022 cm−2 hydrogen ions (60 eV) were found to have a better hydrogen irradiation resistance than Cr20Mn17Fe18Ta23W22 RHEA. The microdefects in irradiated Cr20Mn17Fe18Ta23W22 mainly existed as hydrogen bubbles, hydrogen-vacancy (H-V) complexes and vacancy/vacancy clusters. The microdefects in irradiated HT3 were mainly vacancies and H-V complexes, while the microdefects in irradiated HT1 mainly existed as vacancies and vacancy clusters, as large amounts of hydrogen were consumed to react with oxides on the HT1 surface. The oxides on the surface of the HT3 sample were more stable than those on HT1 under hydrogen irradiation.
Magnesium Potassium Phosphate Cement-Based Derivatives for Construction Use: Experimental Assessment
Authors: Marušiak Šimon , Kapicová Adéla , Pivák Adam , Pavlíková Milena , Pavlík Zbyšek
Published: March 2022

The presented research is focused on the development and testing of the magnesium potassium phosphate cement-based materials (MKPC-based). Firstly, the fresh state properties of the pastes consisting of dead burned magnesia powder, potassium dihydrogen phosphate, setting retarder borax applied in the range of 0–10 wt.%, and batch water were investigated. The aim of testing was to characterize the hydration process in dependence on the borax content. The properties of raw MgO powder were described by chemical composition and particle size distribution. The properties tested in fresh state included shear stress (viscosity), Young’s modulus of elasticity, and temperature; their time dependence was observed. The measurements started immediately after the mixing process. At the age of 14 days, basic structural and mechanical properties of the hardened pastes were obtained. The mixture with 5 wt.% of borax proved to be the most advantageous in terms of setting time, sample integrity, and mechanical strength; therefore, it was chosen as the binder for the following part of the study—MKPC-based mortar development. In the next step, the MKPC paste containing 5 wt.% of borax was supplemented by silica sand aggregate, and the resulting material was marked as a reference. Subsequently, three other mixtures were derived by replacing 100% of quartz sand by lightweight aggregate; namely by expanded glass aggregate, waste rubber from tires, and combination of both in ratio 1:1. The aggregates were characterized by chemical composition (except for the rubber granulate), and loose and compacted powder density. For the resulting hardened composites, basic structural, hygric, strength, and thermal parameters were investigated. The use of lightweight aggregates brought in a considerable decrease in heat transport parameters and low water permeability while maintaining sufficient strength. The favorable obtained material properties are underscored by the fact that magnesia-phosphate is considered to be a low-carbon binder. The combination of magnesia-phosphate binder and recycled aggregate provides a satisfying, environmentally friendly, and thermally efficient alternative to traditional Portland cement-based materials.
Optimization of Mechanical Efficiency Models for 2D Piston Pumps with a Stacked Taper Roller Set
Authors: Wang Heyuan , Tong Chengwei , Ruan Chuantan , Ding Chuan , Li Sheng , Ruan Jian
Published: March 2022

Since the clearance between the guide rail and the roller reduces the efficiency of the 2D pump, this paper proposes a novel 2D piston pump with stacked taper roller sets to eliminate the effect of the clearance. The structure of the 2D pump is introduced, and the mathematical model of the torque and the mechanical efficiency of the bilateral force on the guide rail are established and analyzed. The model takes into account the change in the oil viscosity, the spatial angle and the oil churning loss. A test rig was built to test the mechanical efficiency under different operating conditions. The unilateral and bilateral force models of the guide rail were compared, which proved that the bilateral force model of the guide rail can predict the mechanical efficiency more accurately than the unilateral force model. In the case of high load pressure, there was a clearance between the test results and the model calculation results. It is speculated that the main reason for this is that the greater oil pressure causes the size of the contact area between the two taper rollers and between the taper roller and the guide rail to become larger. The resulting rolling friction coefficient becomes larger, which affects the mechanical efficiency.
Tuning of the Magnetocaloric Properties of Mn5Ge3 Compound by Chemical Modification
Authors: Synoradzki Karol , Urban Krzysztof , Skokowski Przemysław , Głowiński Hubert , Toliński Tomasz
Published: March 2022

The rare earth-free Mn5Ge3 compound shows magnetocaloric properties similar to those of pure Gd; therefore, it is a good candidate for magnetic refrigeration technology. In this work, we investigate the influence of chemical substitution on the crystal structure and the magnetic, thermodynamic, and magnetocaloric properties of a polycrystalline Mn5Ge3 compound prepared by induction melting. For this purpose, we replaced 5% of the Mn with Cr or Co and 5% of the Ge with B or Al. The additional chemical elements were shown not to change the crystal structure of the parent compound (space group P63/mcm, No. 193). In the case of the magnetic properties, all samples remained ferromagnetic with the ordering temperature (TC) lower than for the original compound (TC = 295(1) K). The exception was the sample with B, where we observed an increase in TC by 3 K. The maximum value of the magnetic entropy change, |∆Sm|MAX (for a magnetic field change of 5 T), decreased from 7.1(1) for Mn5Ge3 to 6.2(1), 6.8(1), 4.8(1), and 5.8(1) J kg−1 K−1 for the alloys with B, Al, Cr, and Co, respectively. The adiabatic temperature change (∆Tad) (for a magnetic field change of 1 T) was determined from the specific heat measurements and was equal to 1.1(1), 1.2(1), 1.2(1), 0.8(1), and 0.8(1) K for Mn5Ge3, Mn5Ge2.85B0.15, Mn5Ge2.85Al0.15, Mn4.75Cr0.25Ge3, and Mn4.75Co0.25Ge3, respectively. The obtained data were compared with those from the literature. It was found that the substitution allowed for tuning of the ordering temperature in a wide temperature range. At the same time, the reduction in the magnetocaloric parameters’ values was relatively small. Therefore, the produced Mn5Ge3-based alloys allow for the expansion of the operation temperature range of the parent compound as a magnetocaloric material.
Magnetic Nanomaterials and Nanostructures in Sample Preparation Prior to Liquid Chromatography
Authors: Antoniou Georgios , Samanidou Victoria
Published: March 2022

Magnetic nanomaterials and nanostructures compose an innovative subject in sample preparation. Most of them are designed according to the properties of the target analytes on each occasion. The unique characteristics of nanomaterials enhance the proficiency at extracting and enriching due to their selective adsorption ability as well as easy separation and surface modification. Their remarkable properties, such as superparamagnetism, biocompatibility and selectivity have established magnetic materials as very reliable options in sample preparation approaches. In order to comprehend the range of utilization at magnetic materials and nanostructures, this review aims to present the most notable examples in sample preparation prior to liquid chromatography (LC) to the community of analytical chemists. Primarily, the review describes the principles of the techniques in which the magnetic materials are utilized and leaned on. Additionally, there is a diligent report about the novel magnetic techniques and finally a comparison to demonstrate the total point of view.
Problem Transformation as a Gateway to the Wider Use of Basic Computational Algorithms
Authors: Gonda Dalibor , Pavlovičová Gabriela , Ďuriš Viliam , Tirpáková Anna
Published: March 2022

The problem transformation method is based on the idea that if we cannot solve the given problem directly, we will transfer it to a situation in which we know how to solve it. The basic feature of the method is the division of the problem into subtasks. Furthermore, it is the division of the problem solution into the solution of partial tasks that will allow the use of already learned algorithms outside the set of problems in which they were taught. The use of the method of transformation develops the necessary students’ transformation skills, and, at the same time, it enables the greater use of ICT in mathematics teaching.
An Efficient Algorithm to Compute the Linear Complexity of Binary Sequences
Authors: Fúster-Sabater Amparo , Requena Verónica , Cardell Sara D.
Published: March 2022

Binary sequences are algebraic structures currently used as security elements in Internet of Things devices, sensor networks, e-commerce, and cryptography. In this work, a contribution to the evaluation of such sequences is introduced. In fact, we present a novel algorithm to compute a fundamental parameter for this kind of structure: the linear complexity, which is related to the predictability (or non-predictability) of the binary sequences. Our algorithm reduced the computation of the linear complexity to just the addition modulo two (XOR logic operation) of distinct terms of the sequence. The performance of this procedure was better than that of other algorithms found in the literature. In addition, the amount of required sequence to perform this computation was more realistic than in the rest of the algorithms analysed. Tables, figures, and numerical results complete the work.
HWVoteRank: A Network-Based Voting Approach for Identifying Coding and Non-Coding Cancer Drivers
Authors: Yu Dongling , Yu Zuguo
Published: March 2022

Cancer drivers play an important role in regulating cell growth, cell cycles, and DNA replication. Identifying these cancer drivers provides cancer researchers with indispensable knowledge that has important implications for clinical decision making. Some methods have been recently proposed to identify coding and non-coding cancer drivers through controllability analysis in network and eigenvector centrality based on community detection. However, the performance of these methods is not satisfactory. In this work, we focus on the strategy of selecting a set of critical nodes in cancer-special network as cancer drivers, and propose a novel approach for identifying coding and non-coding drives via a network-based voting mechanism. We name our approach HWVoteRank. Compared with two recent methods to identify cancer drivers, CBNA and NIBNA, and three algorithms for identifying key nodes on BRCA dataset, our method can achieve the best efficiency. By analyzing the results, it is found that our approach has better ability in identifying miRNA cancer drivers. We also applied our approach to identification of drivers of miRNA during Epithelial–Mesenchymal transition and drivers for cancer subtype. Through literature research, we found that those drivers explored by our approach are of biological significance.
A Combined Experimental-Numerical Investigation of the Thermal Efficiency of the Vessel in Domestic Induction Systems
Authors: Bonet-Sánchez Belén , Cabeza-Gil Iulen , Calvo Begoña , Grasa Jorge , Franco Carlos , Llorente Sergio , Martínez Miguel A.
Published: March 2022

New studies are emerging to reduce energy costs and become a more sustainable society. One of the processes where the greatest savings can be made is in cooking, due to its large-scale global use. In this vein, this study aims to analyse the influence of the vessel in the thermal efficiency at the cooking process. For that purpose, a numerical model of a cooking vessel was designed and validated with three different experimental heating tests. One of the key factors of the process is the contact between the vessel and the glass, therefore, two new approaches to model the thermal contact between the vessel and the cooktop were explored. Once the numerical models were calibrated, a full factorial analysis was performed to quantify the influence of the key parameters of the vessel in the heating process during cooking (thermal conductivity, specific heat, convection and radiation coefficients, and vessel concavity). Two of the most influential parameters in the heating process are the conductivity and the thermal contact between the vessel and the glass. Higher cooking efficiency can be achieved both with a low thermal conductivity vessel and with a high concavity, i.e., increasing the isolation between the vessel and the glass.
New Metabolites from the Marine Sponge Scopalina hapalia Collected in Mayotte Lagoon
Authors: Saïd Hassane Charifat , Herbette Gaëtan , Garayev Elnur , Mabrouki Fathi , Clerc Patricia , de Voogd Nicole J. , Greff Stephane , Trougakos Ioannis P. , Ouazzani Jamal , Fouillaud Mireille , Dufossé Laurent , Baghdikian Béatrice , Ollivier Evelyne , Gauvin-Bialecki Anne
Published: March 2022

The biological screening of 44 marine sponge extracts for the research of bioactive molecules, with potential application in the treatment of age-related diseases (cancer and Alzheimer’s disease) and skin aging, resulted in the selection of Scopalina hapalia extract for chemical study. As no reports of secondary metabolites of S. hapalia were found in the literature, we undertook this research to further extend current knowledge of Scopalina chemistry. The investigation of this species led to the discovery of four new compounds: two butenolides sinularone J (1) and sinularone K (2), one phospholipid 1-O-octadecyl-2-pentanoyl-sn-glycero-3-phosphocholine (3) and one lysophospholipid 1-O-(3-methoxy-tetradecanoyl)-sn-glycero-3-phosphocholine (4) alongside with known lysophospholipids (5 and 6), alkylglycerols (7–10), epidioxysterols (11 and 12) and diketopiperazines (13 and 14). The structure elucidation of the new metabolites (1–4) was determined by detailed spectroscopic analysis, including 1D and 2D NMR as well as mass spectrometry. Molecular networking was also explored to complement classical investigation and unravel the chemical classes within this species. GNPS analysis provided further information on potential metabolites with additional bioactive natural compounds predicted.
Six Revision Surgeries for Massive Epidural Fibrosis with Recurrent Pain and Weakness in the Left Lower Extremity
Authors: Choi Ho Yong , Jo Dae Jean
Published: March 2022

Epidural fibrosis is a common cause of pain after lumbar surgeries. There are no previous reports documenting profound limb weakness associated with epidural fibrosis. A 43-year-old woman uneventfully underwent microscopic discectomy. However, six additional surgeries were needed due to recurrent pain and weakness episodes, several days after the surgery. Operative findings were severe epidural fibrosis around the thecal sac and nerve roots. Epidural fibrosis excision did not prevent recurrent fibrosis; therefore, we performed a lordotic fusion with posterior column shortening to reduce neural tension and nerve-root stretching. Eventually, she became free from recurrent episodes of deteriorations and repetitive surgeries.
Clinical Manifestations and Outcomes of Tubercular Uveitis in Taiwan—A Ten-Year Multicenter Retrospective Study
Authors: Lin Chun-Ju , Hsia Ning-Yi , Hwang De-Kuang , Hwang Yih-Shiou , Chang Yo-Chen , Lee Yueh-Chang , Hsu Yung-Ray , Yeh Po-Ting , Lin Chang-Ping , Chen Hsi-Fu , Jan Wei-Chun , Chiang Wei-Yu , Tsai Ming-Ling
Published: March 2022

Background andObjectives: This 10-year multicenter retrospective study reviewed the clinical manifestations, diagnostic tests, and treatment modalities of tubercular uveitis (TBU), including direct infection and indirect immune-mediated hypersensitivity to mycobacterial antigens in Taiwan. Materials and Methods: This retrospective chart review of patients with TBU was conducted at 11 centers from 1 January 2008 to 31 December 2017. We used a multiple regression model to analyze which factors influenced best-corrected visual acuity (BCVA) improvement. Results: A total of 79 eyes from 51 patients were included in the study. The mean age was 48.9 ± 16.4 years. The mean change of LogMAR BCVA at last visit was −0.21 ± 0.45. Diagnostic tools used include chest X-ray, chest computed tomography, Mantoux test, interferon gamma release test (QuantiFERON-TB Gold test), intraocular fluid tuberculosis polymerase chain reaction, and bronchial alveolar lavage. The clinical manifestations included 48% posterior uveitis and 37% panuveitis. In the sample, 55% of the cases were bilateral and 45% unilateral. There was 60.76% retinal vasculitis, 35.44% choroiditis, 21.52% serpiginous-like choroiditis, 17.72% vitreous hemorrhage, 12.66% posterior synechiae, 6.33% retinal detachment, and 3.80% choroidal granuloma. Treatment modalities included rifampicin, isoniazid, pyrazinamide, ethambutol, oral steroid, posterior triamcinolone, non-steroidal anti-inflammatory drugs, vitrectomy, and immunosuppressants. BCVA improved in 53.2% of eyes and remained stable in 32.9% of eyes. In the final model of multiple regression, worse initial BCVA, pyrazinamide, and receiving vitrectomy predicted better BCVA improvement. Ethambutol was associated with worse visual outcomes. Seven eyes experienced recurrence. Conclusions: This is the largest 10-year multicenter retrospective study of TBU in Taiwan to date, demonstrating the distribution of clinical manifestations and clinical associations with better treatment outcomes. The study provides a comprehensive description of TBU phenotypes in Taiwan and highlights considerations for the design of further prospective studies to reliably assess the role of ATT and vitrectomy in patients with TBU.
Broadband Zero-Power Wakeup MEMS Device for Energy-Efficient Sensor Nodes
Authors: Ahmed Minhaz , Dankwort Torben , Grünzig Sven , Lange Volker , Gojdka Björn
Published: March 2022

A zero-power wakeup scheme for energy-efficient sensor applications is presented in this study based on a piezoelectric MEMS energy harvester featuring wafer-level-integrated micromagnets. The proposed setup overcomes a hybrid assembly of magnets on a chip-level, a major drawback of similar existing solutions. The wakeup device can be excited at low frequencies by frequency up-conversion, both in mechanical contact and contactless methods due to magnetic force coupling, allowing various application scenarios. In a discrete circuit, a wakeup within 30–50 ms is realized in frequency up-conversion at excitation frequencies < 50 Hz. A power loss in the off state of 0.1 nW renders the scheme virtually lossless. The potential extension of battery lifetime compared to cyclical wakeup schemes is discussed for a typical wireless sensor node configuration.
Effect of Polyolefin Elastomers’ Characteristics and Natural Magnesium Hydroxide Content on the Properties of Halogen-Free Flame-Retardant Polyolefin Composites
Authors: Meucci Michela , Haveriku Sara , Badalassi Marco , Cardelli Camillo , Ruggeri Giacomo , Pucci Andrea
Published: March 2022

This study examines the preparation of several composites that are based on natural magnesium hydroxide (n-MDH) and various poly(ethylene-co-octene) polyolefin elastomers (POEs). Design of experiment (DoE) principles have been applied in order to optimize the mechanical, rheological, and flame-retardant properties of the final composites. DoE allows one to evaluate the influence of each variable on an experiment’s final properties. By increasing the density and crystallinity of the POE, a higher elastic modulus was obtained, which resulted in greater tensile strength and lower elongation at break. Improved flame retardant properties (as measured by the limiting oxygen index (LOI) and vertical burning tests) were obtained by increasing the amount of filler within the composite up to 65% and using a polymer with high crystallinity. More specifically, the best balance between mechanical, rheological, and flame retardant properties was provided by DoE using 63.75% n-MDH filler. The agreement between the predicted performance and the final properties of the composites has enabled the innovative use of DoE to provide reliable predictions about the final mechanical and flame retardant properties of the compounds that are used for low voltage electrical cable applications.
Fluid Properties and Genesis of Dolomites in the Devonian Guanwushan Formation of Upper Yangtze Platform, SW China
Authors: Huang Shuguang , Hou Mingcai , Chen Anqing , Xu Shenglin , Zhang Benjian , Deng Yuwei , Yu Yu
Published: March 2022

The Guanwushan Formation (GWSF) of Devonian dolomite are extensively developed in the northwest of Sichuan Basin in the Upper Yangtze region, but the properties of dolomitization fluid and the geneses are still unclear. Three types of dolomites can be divided by petrological characteristics: the fine-microcrystalline dolomites (FMD), the fine crystalline dolomites (FCD) and the medium crystalline dolomites (MCD). The order degree of these three types of dolomites increased in turn, and they all showed dark cathodoluminescence (CL) luminescence. The total amount of Rare Earth Elements (∑REE) of the dolomite was low, while the dolomite enriched with light REE and lacking heavy REE presented a distribution pattern consistent with that of limestone. The weak negative anomalies of the Ce and Eu indicated that the dolomites were formed in a weak redox environment with relatively low temperature. The dolomitization fluids were inherited from the original seawater. The respective δ13CPDB values of the three types of dolomites varied a little, indicating that they were not affected by the biological effects. Specifically, the δ18OPDB values of the FMD and FCD dolomites were higher than that of the limestone, indicating that the dolomitization fluid was influenced by evaporation at the penecontemporaneous stage. The interpretations were also supported by the 87Sr/86Sr ratios, as the 87Sr/86Sr ratios of FMD comparable to the Middle Devonian seawater. The δ18OPDB value of the MCD dolomite was lower than that of the limestone. It also showed poor automorphic extent, which clarified that the dolomite experienced more intense dolomitization in greater burial depth and at higher temperatures.
ZIF-67 Derived Co2VO4 Hollow Nanocubes for High Performance Asymmetric Supercapacitors
Authors: Li Chengda , Ma Dongliang , Zhu Qinglin
Published: March 2022

In this work, a new type of Co2VO4 hollow nanocube (CoVO-HNC) was synthesized through an ion exchange process using ZIF-67 nanocubes as a template. The hollow nanocubic structure of the CoVO-HNC provides an abundance of redox sites and shortens the ion/electron diffusion path. As the electrode material of supercapacitors, the specific capacitance of CoVO-HNC is 427.64 F g−1 at 1.0 A g−1. Furthermore, an asymmetric supercapacitor (ASC) was assembled using CoVO-HNC and activated carbon (AC) as electrodes. The ASC device attains an energy density of 25.28 Wh kg−1 at a high-power density of 801.24 W kg−1, with 78% capacitance retention after 10,000 cycles at 10 A g−1.
Influence of Synthesis Conditions on Gadolinium-Substituted Tricalcium Phosphate Ceramics and Its Physicochemical, Biological, and Antibacterial Properties
Authors: Fadeeva Inna , Deyneko Dina , Barbaro Katia , Davydova Galina , Sadovnikova Margarita , Murzakhanov Fadis , Fomin Alexander , Yankova Viktoriya , Antoniac Iulian , Barinov Sergey , Lazoryak Bogdan , Rau Julietta
Published: March 2022

Gadolinium-containing calcium phosphates are promising contrast agents for various bioimaging modalities. Gadolinium-substituted tricalcium phosphate (TCP) powders with 0.51 wt% of gadolinium (0.01Gd-TCP) and 5.06 wt% of (0.1Gd-TCP) were synthesized by two methods: precipitation from aqueous solutions of salts (1) (Gd-TCP-pc) and mechano-chemical activation (2) (Gd-TCP-ma). The phase composition of the product depends on the synthesis method. The product of synthesis (1) was composed of β-TCP (main phase, 96%), apatite/chlorapatite (2%), and calcium pyrophosphate (2%), after heat treatment at 900 °C. The product of synthesis (2) was represented by β-TCP (main phase, 73%), apatite/chlorapatite (20%), and calcium pyrophosphate (7%), after heat treatment at 900 °C. The substitution of Ca2+ ions by Gd3+ in both β-TCP (main phase) and apatite (admixture) phases was proved by the electron paramagnetic resonance technique. The thermal stability and specific surface area of the Gd-TCP powders synthesized by two methods were significantly different. The method of synthesis also influenced the size and morphology of the prepared Gd-TCP powders. In the case of synthesis route (1), powders with particle sizes of tens of nanometers were obtained, while in the case of synthesis (2), the particle size was hundreds of nanometers, as revealed by transmission electron microscopy. The Gd-TCP ceramics microstructure investigated by scanning electron microscopy was different depending on the synthesis route. In the case of (1), ceramics with grains of 1–50 μm, pore sizes of 1–10 µm, and a bending strength of about 30 MPa were obtained; in the case of (2), the ceramics grain size was 0.4–1.4 μm, the pore size was 2 µm, and a bending strength of about 39 MPa was prepared. The antimicrobial activity of powders was tested for four bacteria (S. aureus, E. coli, S. typhimurium, and E. faecalis) and one fungus (C. albicans), and there was roughly 30% of inhibition of the micro-organism’s growth. The metabolic activity of the NCTC L929 cell and viability of the human dental pulp stem cell study demonstrated the absence of toxic effects for all the prepared ceramic materials doped with Gd ions, with no difference for the synthesis route.
Preparation, Characterization, and Bioactivity Evaluation of Polyoxymethylene Copolymer/Nanohydroxyapatite-g-Poly(ε-caprolactone) Composites
Authors: Pielichowska Kinga , Szuba Paula , Maciocha Joanna , Macherzyńska Beata , Nowicka Katarzyna , Szatkowski Piotr
Published: March 2022

In this work, nanohydroxyapatite (HAp) was functionalized with poly(ε-caprolactone) (PCL), using 1,6-hexamethylene diisocyanate (HDI) as a coupling agent, and then incorporated into the polyoxymethylene copolymer (POM) matrix using the extrusion technique. The obtained POM/HAp-g-PCL composites were investigated using FTIR, DSC, TOPEM DSC, and TG methods. Mechanical properties were studied using destructive and non-destructive ultrasonic methods, wettability, and POM crystallization kinetics in the presence of HAp-g-PCL. Moreover, preliminary bioactivity evaluation of the POM/HAp-g-PCL composites was performed using the Kokubo method. It was found that the introduction of HAp-g-PCL to the POM matrix has a limited effect on the phase transitions of POM as well as on its degree of crystallinity. Importantly, HAp grafted with PCL caused a significant increase in the thermal stability of the POM, from 292 °C for pristine POM to 333 °C for POM modified with 2.5% HAp-g-PCL. If unmodified HAp was used, a distinct decrease in the thermal stability of the POM was observed. Crystallization kinetic studies confirmed that HAp-g-PCL, in small amounts, can act as a nucleating agent for the POM crystallization process. Moreover, incorporation of HAp-g-PCL, although slightly decreasing the mechanical properties of POM composites, improved the crucial parameter in biomedical applications, namely the in vitro bioactivity.
Feasibility of Food FARMacia: Mobile Food Pantry to Reduce Household Food Insecurity in Pediatric Primary Care
Authors: Woo Baidal Jennifer A. , Meyer Dodi , Partida Ivette , Duong Ngoc , Rosenthal Alyson , Hulse Emma , Nieto Andres ,   on behalf of the HERALD Collaborative
Published: March 2022

Despite recommendations for systematic food insecurity screening in pediatric primary care, feasible interventions in clinical settings are lacking. The goal of this study was to examine reach, feasibility, and retention in Food FARMacia, a pilot clinically based food insecurity intervention among children aged <6 years. We examined electronic health record data to assess reach and performed a prospective, longitudinal study of families in Food FARMacia (May 2019 to January 2020) to examine attendance and retention. We used descriptive statistics and bivariate analyses to assess outcomes. Among 650 pediatric patients, 172 reported household food insecurity and 50 registered for Food FARMacia (child mean age 22 ± 18 months; 88% Hispanic/Latino). Demographic characteristics of Food FARMacia participants were similar to those of the target group. Median attendance rate was 75% (10 sessions) and retention in both the study and program was 68%. Older child age (retention: age 26.7 ± 18.7 months vs. attrition: age 12.1 ± 13.8 months, p = 0.01), Hispanic/Latino ethnicity (retention: 97% vs. attrition: 69%, p < 0.01), and larger household size (retention: 4.5 ± 1.1 vs. attrition: 3.7 ± 1.4, p = 0.04) correlated with retention. A clinically based mobile food pantry pilot program and study reached the target population and were feasible.
The Glycemic Response to Infant Formulas: A Randomized Clinical Trial
Authors: Anafy Adi , Moran-Lev Hadar , Shapira Niva , Priel Meital , Oren Asaf , Mangel Laurence , Mandel Dror , Lubetzky Ronit
Published: March 2022

Background: Commercial infant formulas attempt to imitate human milk’s unique composition. However, lactose-free and milk protein-free formulas are often chosen due to medical reasons or personal preferences. The aim of this study was to determine the glycemic and insulinemic indices of a variety of infant formulas. Methods: We conducted a three-arm, randomized, double-blind, crossover study. Participants were 25–40-year-old healthy adults. Three commercial infant formulas (cow’s milk protein-based [“standard”], soy protein-based, and lactose-free) were randomly given to each participant. Glycemic and insulinemic responses were determined and compared between the three formulas. Results: Twenty subjects were enrolled (11 females/9 males, mean age 32.8 ± 2.9 years). No significant difference was found in the glycemic index between the three formulas (21.5, 29.1, and 21.5 for the standard, soy protein-based, and lactose-free formulas, respectively, p = 0.21). However, maximal glucose levels were significantly higher for the soy protein-based formula compared to both the standard and lactose-free formulas (111.5 compared to 101.8 and 105.8 mg/dL, respectively, p = 0.001). Conclusion: Cow’s milk protein-based, soy protein-based, and lactose-free formulas have a similar glycemic index. However, soy protein-based formula produced a significantly higher increase in postprandial glucose levels. The implication and biological significance of these results have yet to be determined.
Milk and Fermented Milk Consumption and Risk of Stroke: Longitudinal Study
Authors: Olsson Erika , Larsson Susanna C. , Höijer Jonas , Kilander Lena , Byberg Liisa
Published: March 2022

The role of milk and fermented milk consumption in stroke risk is unclear. We investigated associations of time-updated information on milk and fermented milk consumption (1997 and 2009) with total stroke, cerebral infarction, and hemorrhagic stroke risk among 79,618 Swedish women and men (mean age 61.3 years). During a mean follow-up of 17.7 years, we identified 9735 incident cases of total stroke, of which 7573 were cerebral infarctions, 1470 hemorrhagic strokes, and 692 unspecified strokes. Compared with an intake of 100 g/day of milk, the multivariable-adjusted hazard ratios (95% confidence interval) of cerebral infarction were 1.05 (1.02–1.08) for 0 g/day, 0.97 (0.95–0.99) for 200 g/day, 0.96 (0.92–1.00) for 400 g/day, 0.98 (0.94–1.03) for 600 g/day, and 1.01 (0.94–1.07) for 800 g/day. Corresponding estimates for hemorrhagic stroke were 0.98 (0.91–1.05) for 0 g/day, 1.02 (0.97–1.07) for 200 g/day, 1.07 (0.98–1.17) for 400 g/day, 1.13 (1.02–1.25) for 600 g/day, and 1.19 (1.03–1.36) for 800 g/day. No associations were observed between milk consumption and total stroke or for fermented milk consumption and any of the stroke outcomes. Higher long-term milk consumption based on repeated measures of intake was weakly and non-linearly associated with cerebral infarction, and was directly associated with hemorrhagic stroke.
Nurses’ Perceived Facilitators of Research Utilisation in a Multicultural Setting in Saudi Arabia: Observational Study
Authors: Almalki Mohammed Saleh , Kimpton Amanda , Jones Linda Katherine , Da Costa Cliff
Published: March 2022

Facilitators of research utilisation are important in the implementation of evidence-based practice. Numerous facilitators for nursing practice have been identified, but knowledge of the impact of demographic characteristics on these enablers of research utilisation is limited. The study’s aim was to determine nurses’ perceptions of the facilitators of research utilisation and assess differences in the facilitator of research utilisation score based on nurses’ demographic characteristics. A total of 2650 registered nurses from five hospitals in Riyadh, Saudi Arabia, were recruited for participation. A facilitator scale and self-designed demographic survey were used for data collection. The number of completed questionnaires was 1824 (69%). The results showed that many of the participants were female, aged between 20 to 40 years, and were expatriates mainly from the Philippines. Most respondents were clinical nurses with 6 to 10 years of experience. Many of the nurses had a bachelor’s degree and a qualification from the Asian region. The mean total facilitator score was 26.1, with strong facilitators of research, including advanced education, providing colleague support, more clinically focused research and employing nurses with research skills. Recommendations for the facilitation of research utilisation include a strengthening of the research curriculum in nursing education programs as well as through continuing professional education.
The Role of Nuclear Factor Kappa B (NF-κB) in the Immune Response against Parasites
Authors: Bąska Piotr , Norbury Luke J.
Published: March 2022

The immune system consists of various cells, organs, and processes that interact in a sophisticated manner to defend against pathogens. Upon initial exposure to an invader, nonspecific mechanisms are raised through the activation of macrophages, monocytes, basophils, mast cells, eosinophils, innate lymphoid cells, or natural killer cells. During the course of an infection, more specific responses develop (adaptive immune responses) whose hallmarks include the expansion of B and T cells that specifically recognize foreign antigens. Cell to cell communication takes place through physical interactions as well as through the release of mediators (cytokines, chemokines) that modify cell activity and control and regulate the immune response. One regulator of cell states is the transcription factor Nuclear Factor kappa B (NF-κB) which mediates responses to various stimuli and is involved in a variety of processes (cell cycle, development, apoptosis, carcinogenesis, innate and adaptive immune responses). It consists of two protein classes with NF-κB1 (p105/50) and NF-κB2 (p100/52) belonging to class I, and RelA (p65), RelB and c-Rel belonging to class II. The active transcription factor consists of a dimer, usually comprised of both class I and class II proteins conjugated to Inhibitor of κB (IκB). Through various stimuli, IκB is phosphorylated and detached, allowing dimer migration to the nucleus and binding of DNA. NF-κB is crucial in regulating the immune response and maintaining a balance between suppression, effective response, and immunopathologies. Parasites are a diverse group of organisms comprised of three major groups: protozoa, helminths, and ectoparasites. Each group induces distinct effector immune mechanisms and is susceptible to different types of immune responses (Th1, Th2, Th17). This review describes the role of NF-κB and its activity during parasite infections and its contribution to inducing protective responses or immunopathologies.
Effects of Drought Stress and Rehydration on Physiological and Biochemical Properties of Four Oak Species in China
Authors: Xiong Shifa , Wang Yangdong , Chen Yicun , Gao Ming , Zhao Yunxiao , Wu Liwen
Published: March 2022

Quercus fabri Hance, Quercus serrata Thunb, Quercus acutissima Carruth, and Quercus variabilis BL are four Chinese oak species commonly used for forestation. To ensure the survival of seedlings, we first need to understand the differences in drought resistance of the four oak species at the seedling stage, and comprehensively evaluate their drought resistance capabilities. The four oak seedlings were divided into drought-rewatering treatment group and well watered samples (control group). For the seedlings of the drought-rewatering treatment group, drought stress lasting 31 days was used, and then re-watering for 5 days. The water parameters, osmotic solutes content, antioxidant enzyme activity and photosynthesis parameters of the seedlings in the two groups were measured every 5 days. Compared with the control group, the relative water content, water potential, net photosynthetic rate, transpiration rate, and stomatal conductance levels of the four oaks all showed a downward trend under continuous drought stress, and showed an upward trend after rehydration. The soluble protein, soluble sugar, proline, peroxidase, superoxide dismutase and catalase content of the four oaks increased first and then decreased under drought stress, and then increased after rehydration. The content of glycine betaine and malondialdehyde continued to increase, and gradually decreased after rehydration. The weight of each index was calculated by principal component analysis, and then the comprehensive evaluation of each index was carried out through the membership function method. The drought resistance levels of the four oak species were as follows: Q. serrata > Q. fabri > Q. variabilis > Q. acutissima.