bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear Optical Characterization of InP@ZnS Core-Shell Colloidal Quantum Dots Using 532 nm, 10 ns Pulses
Authors: Ganeev Rashid A. , Zvyagin Andrey I. , Shuklov Ivan A. , Spirin Maksim G. , Ovchinnikov Oleg V. , Razumov Vladimir F.
Published: May 2021

InP@ZnS core-shell colloidal quantum dots (CQDs) were synthesized and characterized using the z-scan technique. The nonlinear refraction and nonlinear absorption coefficients (γ = −2 × 10−12 cm2 W−1, β = 4 × 10−8 cm W−1) of these CQDs were determined using 10 ns, 532 nm pulses. The saturable absorption (β = −1.4 × 10−9 cm W−1, Isat = 3.7 × 108 W cm−2) in the 3.5 nm CQDs dominated at small intensities of the probe pulses (I ≤ 7 × 107 W cm−2) followed by reverse saturable absorption at higher laser intensities. We report the optical limiting studies using these CQDs showing the suppression of propagated nanosecond radiation in the intensity range of 8 × 107–2 × 109 W cm−2. The role of nonlinear scattering is considered using off-axis z-scan scheme, which demonstrated the insignificant role of this process along the whole range of used intensities of 532 nm pulses. We discuss the thermal nature of the negative nonlinear refraction in the studied species.
Phase Transitions in the “Spinel-Layered” Li1+xNi0.5Mn1.5O4 (x = 0, 0.5, 1) Cathodes upon (De)lithiation Studied with Operando Synchrotron X-ray Powder Diffraction
Authors: Drozhzhin Oleg A. , Alekseeva Anastasia M. , Shevchenko Vitalii A. , Chernyshov Dmitry , Abakumov Artem M. , Antipov Evgeny V.
Published: May 2021

“Spinel-layered” Li1+xNi0.5Mn1.5O4 (x = 0, 0.5, 1) materials are considered as a cobalt-free alternative to currently used positive electrode (cathode) materials for Li-ion batteries. In this work, their electrochemical properties and corresponding phase transitions were studied by means of synchrotron X-ray powder diffraction (SXPD) in operando regime. Within the potential limit of 2.2–4.9 V vs. Li/Li+ LiNi0.5Mn1.5O4 with cubic spinel type structure demonstrates the capacity of 230 mAh·g−1 associated with three first-order phase transitions with significant total volume change of 8.1%. The Li2Ni0.5Mn1.5O4 material exhibits similar capacity value and subsequence of the phase transitions of the spinel phase, although the fraction of the spinel-type phase in this material does not exceed 30 wt.%. The main component of Li2Ni0.5Mn1.5O4 is Li-rich layered oxide Li(Li0.28Mn0.64Ni0.08)O2, which provides nearly half of the capacity with very small unit cell volume change of 0.7%. Lower mechanical stress associated with Li (de)intercalation provides better cycling stability of the spinel-layered complex materials and makes them more perspective for practical applications compared to the single-phase LiNi0.5Mn1.5O4 high-voltage cathode material.
Feature-Rich Geometric and Electronic Properties of Carbon Nanoscrolls
Authors: Lin Shih-Yang , Chang Sheng-Lin , Chiang Cheng-Ru , Li Wei-Bang , Liu Hsin-Yi , Lin Ming-Fa
Published: May 2021

How to form carbon nanoscrolls with non-uniform curvatures is worthy of a detailed investigation. The first-principles method is suitable for studying the combined effects due to the finite-size confinement, the edge-dependent interactions, the interlayer atomic interactions, the mechanical strains, and the magnetic configurations. The complex mechanisms can induce unusual essential properties, e.g., the optimal structures, magnetism, band gaps and energy dispersions. To reach a stable spiral profile, the requirements on the critical nanoribbon width and overlapping length will be thoroughly explored by evaluating the width-dependent scrolling energies. A comparison of formation energy between armchair and zigzag nanoscrolls is useful in understanding the experimental characterizations. The spin-up and spin-down distributions near the zigzag edges are examined for their magnetic environments. This accounts for the conservation or destruction of spin degeneracy. The various curved surfaces on a relaxed nanoscroll will create complicated multi-orbital hybridizations so that the low-lying energy dispersions and energy gaps are expected to be very sensitive to ribbon width, especially for those of armchair systems. Finally, the planar, curved, folded, and scrolled graphene nanoribbons are compared with one another to illustrate the geometry-induced diversity.
Efficient Visible-Light Photocatalysis of TiO2-δ Nanobelts Utilizing Self-Induced Defects and Carbon Doping
Authors: Seo Dong-Bum , Bae Sung-Su , Kim Eui-Tae
Published: May 2021

Efficient visible-light photocatalysis was realized by exploring self-induced defect states, including the abundant surface states of TiO2-δ nanobelts synthesized through metal–organic chemical vapor deposition (MOCVD). The TiO2-δ nanobelts exhibited two strong defect-induced absorption peaks at 2.91 and 1.92 eV, overlapping with the conduction band states so that photoexcited carriers can contribute effectively for the photocatalysis reaction. To further enhance visible-light photocatalytic activity, carbon atoms, the by-product of the MOCVD reaction, were self-doped at the judiciously determined growth conditions. The resulting visible-light photocatalysis suggests that the large surface area and consequent high concentration of the surface states of the TiO2-δ nanobelts can be effectively utilized in a wide range of photocatalysis applications.
Magnetic Simulations of Core–Shell Ferromagnetic Bi-Magnetic Nanoparticles: The Influence of Antiferromagnetic Interfacial Exchange
Authors: Ramos-Guivar Juan A. , Tamanaha-Vegas Carlo A. , Litterst Fred Jochen , Passamani Edson C.
Published: May 2021

Magnetic properties of ferromagnetic nanostructures were studied by atomistic simulations following Monte Carlo and Landau–Lifshitz–Gilbert approaches. First, we investigated the influence of particle size and shape on the temperature dependence of magnetization for single cobalt and gadolinium nanoparticles and also in bi-magnetic Co@Gd core–shell nanoparticles with different sizes. The Landau–Lifshitz–Gilbert approach was subsequently applied for inspecting the magnetic hysteresis behavior of 2 and 4 nm Co@Gd core–shell nanoparticles with negative, positive, and zero values of interfacial magnetic exchange. We were able to demonstrate the influence of finite-size effect on the dependence of the Curie temperature of Co and Gd nanoparticles. In the Co@Gd core–shell framework, it was possible to handle the critical temperature of the hybrid system by adjusting the Co core size. In addition, we found an improvement in the coercive field values for a negative interfacial exchange energy and for a different core size, suggesting an exchange spring behavior, while positive and zero values of interfacial exchange constant showed no strong influence on the hysteresis behavior.
Nothing in Cognitive Neuroscience Makes Sense Except in the Light of Evolution
Authors: Vilarroya Oscar
Published: May 2021

Evolutionary theory should be a fundamental guide for neuroscientists. This would seem a trivial statement, but I believe that taking it seriously is more complicated than it appears to be, as I argue in this article. Elsewhere, I proposed the notion of “bounded functionality” As a way to describe the constraints that should be considered when trying to understand the evolution of the brain. There are two bounded-functionality constraints that are essential to any evolution-minded approach to cognitive neuroscience. The first constraint, the bricoleur constraint, describes the evolutionary pressure for any adaptive solution to re-use any relevant resources available to the system before the selection situation appeared. The second constraint, the satisficing constraint, describes the fact that a trait only needs to behave more advantageously than its competitors in order to be selected. In this paper I describe how bounded-functionality can inform an evolutionary-minded approach to cognitive neuroscience. In order to do so, I resort to Nikolaas Tinbergen’s four questions about how to understand behavior, namely: function, causation, development and evolution. The bottom line of assuming Tinbergen’s questions is that any approach to cognitive neuroscience is intrinsically tentative, slow, and messy.
Occurrence of Listeria monocytogenes in Artisanal Cheeses from Poland and Its Identification by MALDI-TOF MS
Authors: Pyz-Łukasik Renata , Gondek Michał , Winiarczyk Dagmara , Michalak Katarzyna , Paszkiewicz Waldemar , Piróg-Komorowska Anna , Policht Agata , Ziomek Monika
Published: May 2021

Listeria monocytogenes is a foodborne pathogen. A source of infection can be artisanal cheeses. Identification of the Listeria species is important for the protection of public health and the food industry. This study aimed to examine artisanal cheeses for the presence of L. monocytogenes and the effectiveness of the MALDI-TOF MS method in the identification of the L. monocytogenes isolates. A total of 370 samples of artisanal cheeses were examined. L. monocytogenes was found in 23 cheese samples (6.2%). The reliability of L. monocytogenes identification achieved by MALDI-TOF MS was varied, and the vast majority of the isolates (27/32) were identified only to the secure genus, probable species level. This study showed that (i) the occurrence of L. monocytogenes in the artisanal cheeses was at a higher level than that in the other EU countries, (ii) the standard of species identification of L. monocytogenes isolates from artisanal cheeses achieved by MALDI-TOF MS was not satisfactory and (iii) the presence of L. monocytogenes in artisanal cheeses remains a problem with regard to the food safety criterion and a potential public health risk.
The Emerging Concern and Interest SARS-CoV-2 Variants
Authors: Janik Edyta , Niemcewicz Marcin , Podogrocki Marcin , Majsterek Ireneusz , Bijak Michal
Published: May 2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for coronavirus disease 2019 (COVID-19) was discovered in December 2019 in Wuhan, China. Since that time, the virus has spread around the world, which resulted in an announcement of the World Health Organization (WHO), dated in March 2020, that COVID-19 was a worldwide pandemic, and since then, the world has been struggling with this disease. SARS-CoV-2, similar to other RNA viruses, continually mutates, and new variants are appearing. Among large numbers of detected SARS-CoV-2 variants, only an insignificant amount of them are able to pose a risk to public health, as they are more contagious and cause more severe conditions. The emerged variants were classified by the Centers for Disease Control and Prevention (CDC) in collaboration with SARS-CoV-2 Interagency Group (SIG) according to strictly defined pattern. Variants were classified as variants of concern, variants of interest, and variants of high consequence. In the last few months, three variants of concern (B.1.1.7, B.1.351, and P.1) and four variants of interests (B.1.526, B.1.525, B.1.427/B.1.429, and P.2) were distinguished and are essential for close monitoring. This analysis summarizes the principal information concerning SARS-CoV-2 variants, such as their infectivity, severity, mutations, and immune susceptibility.
Fundamental and Advanced Therapies, Vaccine Development against SARS-CoV-2
Authors: Hudakova Nikola , Hricikova Simona , Kulkarni Amod , Bhide Mangesh , Kontsekova Eva , Cizkova Dasa
Published: May 2021

Coronavirus disease (COVID-19) caused by the SARS-CoV-2 virus has been affecting the world since the end of 2019. The severity of the disease can range from an asymptomatic or mild course to acute respiratory distress syndrome (ARDS) with respiratory failure, which may lead to death. Since the outbreak of the pandemic, scientists around the world have been studying the genome and molecular mechanisms of SARS-CoV-2 infection to develop effective therapies and prevention. In this review, we summarize the progressive development of various treatments and vaccines as they have emerged, a year after the outbreak of the pandemic. Initially for COVID-19, patients were recommended drugs with presumed antiviral, anti-inflammatory, and antimicrobial effects that were previously used to treat other diseases. Thereafter, therapeutic interventions were supplemented with promising approaches based on antibodies, peptides, and stem cells. However, licensed COVID-19 vaccines remain the most effective weapon in combating the pandemic. While there is an enormous effort to enhance the vaccination rate to increase the entire population immunity, the production and delivery of vaccines is becoming limited in several countries. In this regard, there are new challenges needing to be addressed by combining non-pharmacological intervention with effective therapies until vaccination is accessible to all.
First Molecular Detection of Babesia gibsoni in Stray Dogs from Thailand
Authors: Do Thom , Ngasaman Ruttayaporn , Saechan Vannarat , Pitaksakulrat Opal , Liu Mingming , Xuan Xuenan , Inpankaew Tawin
Published: May 2021

In southern Thailand, the increasingly growing population of stray dogs is a concern to public health and environmental safety because of the lack of medical attention and control. More importantly, these animals are considered reservoirs for many zoonotic pathogens. The objective of this study was to molecularly detect canine vector-borne pathogens, and to perform genetic characterization of Babesia gibsoni present in stray dogs from southern Thailand. Blood samples were collected from 174 stray dogs in two provinces (Songkhla and Narathiwat) in southern Thailand. PCR analyses were executed using specific primers based on the Babesia spp. 18S rRNA gene, Babesia gibsoni Internal transcribed spacer 1 (ITS1) region, Ehrlichia canis citrate synthase (gltA) gene, Hepatozoon spp. 18S rRNA gene and Anaplasma platys heat shock protein (groEL) gene. The most common canine vector-borne pathogen found infecting stray dogs in this study was Hepatozoon canis (24.7%) followed by A. platys (14.9%), Babesia vogeli (8.0%), B. gibsoni (6.3%), and E. canis (1.72%). Concurrent infection with more than one pathogen occurred in 72 cases. Phylogenetic analysis based on the ITS1 region and 18S rRNA gene revealed that the B. gibsoni isolates from this study shared a large proportion of their identities with each other and with other reported B. gibsoni genotypes from Asia. This study highlights the molecular detection of B. gibsoni in dogs in Thailand for the first time and presents the genetic characterization by sequencing the ITS1 region and 18S rRNA gene of B. gibsoni from Thailand. Follow-up studies are needed to elucidate the origin, distribution, and vectors of B. gibsoni parasites circulating in dogs in Thailand, as well as to determine to what extent dogs are important reservoir hosts for zoonotic canine vector-borne disease infection in the studied area.
Prevalence and Genetic Diversity of Avian Haemosporidian Parasites in Southern Iran
Authors: Ghaemitalab Vajiheh , Mirshamsi Omid , Valkiūnas Gediminas , Aliabadian Mansour
Published: May 2021

Avian haemosporidians are widespread and diverse and are classified in the genera Plasmodium, Haemoproteus, Leucocytozoon, and Fallisia. These species are known to cause haemosporidiosis and decreased fitness of their hosts. Despite the high diversity of habitats and animal species in Iran, only few studies have addressed avian haemosporidians in this geographic area. This study was performed in the south and southeast of Iran during the bird breeding seasons in 2017 and 2018, with the aim to partly fill in this gap. Blood samples of 237 passerine birds belonging to 41 species and 20 families were collected. Parasite infections were identified using a nested PCR protocol targeting a 479-base-pair fragment of the mitochondrial cytochrome b (cytb) gene of Haemoproteus, Plasmodium and Leucocytozoon species. The overall prevalence of haemosporidian parasites was 51.1%, and 55 different lineages were identified, of which 15 cytb lineages were new globally. The lineages of Haemoproteus predominated (63.6% of all detected lineages), followed by Leucocytozoon and Plasmodium. Nineteen new host records of haemosporidian cytb lineages were identified, and the majority of them were found in resident bird species, indicating local transmission. Thirteen co-infections (9.8% of infected individuals) of Haemoproteus and Leucocytozoon parasites in seven host species were observed. This study shows the presence of active local transmission of parasites to resident bird species in the southeast of Iran and contributes to the knowledge on haemosporidian parasite biodiversity in this poorly studied region of the world.
Comparative Performance of Eight PCR Methods to Detect Cryptosporidium Species
Authors: Costa Damien , Soulieux Louise , Razakandrainibe Romy , Basmaciyan Louise , Gargala Gilles , Valot Stéphane , Dalle Frédéric , Favennec Loic
Published: May 2021

Diagnostic approaches based on PCR methods are increasingly used in the field of parasitology, particularly to detect Cryptosporidium. Consequently, many different PCR methods are available, both “in-house” and commercial methods. The aim of this study was to compare the performance of eight PCR methods, four “in-house” and four commercial methods, to detect Cryptosporidium species. On the same DNA extracts, performance was evaluated regarding the limit of detection for both C. parvum and C. hominis specificity and the ability to detect rare species implicated in human infection. Results showed variations in terms of performance. The best performance was observed with the FTD® Stool parasites method, which detected C. parvum and C. hominis with a limit of detection of 1 and 10 oocysts/gram of stool respectively; all rare species tested were detected (C. cuniculus, C. meleagridis, C. felis, C. chipmunk, and C. ubiquitum), and no cross-reaction was observed. In addition, no cross-reactivity was observed with other enteric pathogens. However, commercial methods were unable to differentiate Cryptosporidium species, and generally, we recommend testing each DNA extract in at least triplicate to optimize the limit of detection.
Drought and Heat Stress in Cool-Season Food Legumes in Sub-Tropical Regions: Consequences, Adaptation, and Mitigation Strategies
Authors: Kumari Venugopalan Visha , Roy Anirban , Vijayan Roshni , Banerjee Purabi , Verma Vivek Chandra , Nalia Arpita , Pramanik Madhusri , Mukherjee Bishal , Ghosh Ananya , Reja Md. Hasim , Chandran Malamal Alickal Sarath , Nath Rajib , Skalicky Milan , Brestic Marian , Hossain Akbar
Published: May 2021

Drought and heat stress are two major abiotic stresses that challenge the sustainability of agriculture to a larger extend. The changing and unpredictable climate further aggravates the efforts made by researchers as well as farmers. The stresses during the terminal stage of cool-season food legumes may affect numerous physiological and biochemical reactions that may result in poor yield. The plants possess a good number of adaptative and avoiding mechanisms to sustain the adverse situation. The various agronomic and breeding approaches may help in stress-induced alteration. The physiological and biochemical response of crops to any adverse situation is very important to understand to develop mechanisms and approaches for tolerance in plants. Agronomic approaches like altering the planting time, seed priming, foliar application of various macro and micro nutrients, and the application of rhizobacteria may help in mitigating the adverse effect of heat and drought stress to some extent. Breeding approaches like trait-based selection, inheritance studies of marker-based selection, genetic approaches using the transcriptome and metabolome may further pave the way to select and develop crops with better heat and drought stress adaptation and mitigation.
Free and Conjugated Phenolic Profiles and Antioxidant Activity in Quinoa Seeds and Their Relationship with Genotype and Environment
Authors: Antognoni Fabiana , Potente Giulia , Biondi Stefania , Mandrioli Roberto , Marincich Lorenzo , Ruiz Karina B.
Published: May 2021

The nutraceutical interest in quinoa (Chenopodium quinoa Willd.) seeds is associated with the presence of macronutrients, micronutrients, minerals, vitamins, and polyphenols. In particular, polyphenols contribute to the health-promoting effects of this food crop, and their levels are influenced by environmental conditions. Production of quinoa is recently being explored in temperate climate areas, including Italy. The aim of this research was to assess the profile of bioactive compounds in seeds of two quinoa varieties, Regalona-Baer and Titicaca, grown in northern Italy, compared to that of seeds of those varieties grown in Chile and Denmark, respectively. High-performance liquid chromatography-diode array detector (HPLC-DAD) analysis of phenolic acid and flavonoid profiles, both in their free and soluble conjugated forms, showed that the main differences between Regalona grown in Chile and Italy were for the free vanillic acid and daidzein contents, while the two Titicaca samples mainly differed in quercetin derivative levels. The total phenolic index was comparable in Titicaca and Regalona, and only a slight decrease in this parameter was found in seeds of the two varieties grown in Italy. The in vitro antioxidant activity of seed extracts, evaluated by means of three different assays, indicated that it correlated with flavonol (quercetin derivative) levels. In conclusion, the results indicate that, although environmental conditions alter the polyphenolic profile and biological activities, it is possible to grow good-quality quinoa in northern Italy.
Rapid Detection of Pityophthorus juglandis (Blackman) (Coleoptera, Curculionidae) with the Loop-Mediated Isothermal Amplification (LAMP) Method
Authors: Rizzo Domenico , Moricca Salvatore , Bracalini Matteo , Benigno Alessandra , Bernardo Umberto , Luchi Nicola , Da Lio Daniele , Nugnes Francesco , Cappellini Giovanni , Salemi Chiara , Cacciola Santa Olga , Panzavolta Tiziana
Published: May 2021

The walnut twig beetle Pityophthorus juglandis is a phloem-boring bark beetle responsible, in association with the ascomycete Geosmithia morbida, for the Thousand Cankers Disease (TCD) of walnut trees. The recent finding of TCD in Europe prompted the development of effective diagnostic protocols for the early detection of members of this insect/fungus complex. Here we report the development of a highly efficient, low-cost, and rapid method for detecting the beetle, or even just its biological traces, from environmental samples: the loop-mediated isothermal amplification (LAMP) assay. The method, designed on the 28S ribosomal RNA gene, showed high specificity and sensitivity, with no cross reactivity to other bark beetles and wood-boring insects. The test was successful even with very small amounts of the target insect’s nucleic acid, with limit values of 0.64 pg/µL and 3.2 pg/µL for WTB adults and frass, respectively. A comparison of the method (both in real time and visual) with conventional PCR did not display significant differences in terms of LoD. This LAMP protocol will enable quick, low-cost, and early detection of P. juglandis in areas with new infestations and for phytosanitary inspections at vulnerable sites (e.g., seaports, airports, loading stations, storage facilities, and wood processing companies).
Macromolecular Engineering of Poly(catechol) Cathodes towards High-Performance Aqueous Zinc-Polymer Batteries
Authors: Patil Nagaraj , Palma Jesus , Marcilla Rebeca
Published: May 2021

Aqueous zinc-polymer batteries (AZPBs) comprising abundant Zn metal anode and redox-active polymer (RAP) cathodes can be a promising solution for accomplishing viable, safe and sustainable energy storage systems. Though a limited number of RAPs have been successfully applied as organic cathodes in AZPBs, their macromolecular engineering towards improving electrochemical performance is rarely considered. In this study, we systematically compare performance of AZPB comprising Zn metal anode and either poly(catechol) homopolymer (named P(4VC)) or poly(catechol) copolymer (named P(4VC86-stat-SS14)) as polymer cathodes. Sulfonate anionic pendants in copolymer not only rendered lower activation energy and higher rate constant, but also conferred lower charge-transfer resistance, as well as facilitated Zn2+ mobility and less diffusion-controlled current responses compared to its homopolymer analogue. Consequently, the Zn||P(4VC86-stat-SS14) full-cell exhibits enhanced gravimetric (180 versus 120 mAh g−1 at 30 mg cm−2) and areal capacity (5.4 versus 3.6 mAh cm−2 at 30 mg cm−2) values, as well as superior rate capability both at room temperature (149 versus 105 mAh g−1 at 150 C) and at −35 °C (101 versus 35 mAh g−1 at 30 C) compared to Zn||P(4VC)100. This overall improved performance for Zn||P(4VC86-stat-SS14) is highly encouraging from the perspective applying macromolecular engineering strategies and paves the way for the design of advanced high-performance metal-organic batteries.
Synthesis of Novel Dental Nanocomposite Resins by Incorporating Polymerizable, Quaternary Ammonium Silane-Modified Silica Nanoparticles
Authors: Nikolaidis Alexandros K. , Koulaouzidou Elisabeth A. , Gogos Christos , Achilias Dimitris S.
Published: May 2021

Diverse approaches dealing with the reinforcement of dental composite resins with quaternary ammonium compounds (QAC) have been previously reported. This work aims to investigate the physicochemical and mechanical performance of dental resins containing silica nanofillers with novel QAC. Different types of quaternary ammonium silane compounds (QASiC) were initially synthesized and characterized with proton nuclear magnetic resonance (1H-NMR) and Fourier transform infrared (FTIR) spectroscopy. Silica nanoparticles were surface modified with the above QASiC and the structure of silanized products (S.QASiC) was confirmed by means of FTIR and thermogravimetric analysis. The obtained S.QASiC were then incorporated into methacrylate based dental resins. Scanning electron microscopy images revealed a satisfactory dispersion of silica nanoclusters for most of the synthesized nanocomposites. Curing kinetics disclosed a rise in both the autoacceleration effect and degree of conversion mainly induced by shorter QASiC molecules. Polymerization shrinkage was found to be influenced by the particular type of S.QASiC. The flexural modulus and strength of composites were increased by 74% and 19%, while their compressive strength enhancement reached up to 19% by adding 22 wt% S.QASiC nanoparticles. These findings might contribute to the proper design of multifunctional dental materials able to meet the contemporary challenges in clinical practice.
Biomimetic Mineralization of Tannic Acid-Supplemented HEMA/SBMA Nanocomposite Hydrogels
Authors: Chen Tai-Yu , Ou Shih-Fu , Chien Hsiu-Wen
Published: May 2021

This study developed a tannic acid (TA)-supplemented 2-hydroxyethyl methacrylate-co-sulfobetaine methacrylate (HEMA-co-SBMA) nanocomposite hydrogel with mineralization and antibacterial functions. Initially, hybrid hydrogels were synthesized by incorporating SBMA into the HEMA network and the influence of SBMA on the chemical structure, water content, mechanical properties, and antibacterial characteristics of the hybrid HEMA/SBMA hydrogels was examined. Then, nanoclay (Laponite XLG) was introduced into the hybrid HEMA/SBMA hydrogels and the effects evaluated of the nanoclay on the chemical structure, water content, and mechanical properties of these supplemented hydrogels. The 50/50 hybrid HEMA/SBMA hydrogel with 30 mg/mL nanoclay showed outstanding mechanical properties (3 MPa) and water content (60%) compared to pure polyHEMA hydrogels. TA then went on to be incorporated into these hybrid nanocomposite hydrogels and its effects investigated on biomimetic mineralization. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) showed that bone-like spheroidal precipitates with a Ca/P ratio of 1.67% were observed after 28 days within these mineralized hydrogels. These mineralized hydrogels demonstrated an almost 1.5-fold increase in compressive moduli compared to the hydrogels without mineralization. These multifunctional hydrogels display good mechanical and biomimetic properties and may have applications in bone regeneration therapies.
Optimization of FFF Process Parameters by Naked Mole-Rat Algorithms with Enhanced Exploration and Exploitation Capabilities
Authors: Chohan Jasgurpreet Singh , Mittal Nitin , Kumar Raman , Singh Sandeep , Sharma Shubham , Dwivedi Shashi Prakash , Saxena Ambuj , Chattopadhyaya Somnath , Ilyas Rushdan A. , Le Chi Hieu , Wojciechowski Szymon
Published: May 2021

Fused filament fabrication (FFF) has numerous process parameters that influence the mechanical strength of parts. Hence, many optimization studies are performed using conventional tools and algorithms. Although studies have also been performed using advanced algorithms, limited research has been reported in which variants of the naked mole-rat algorithm (NMRA) are implemented for solving the optimization issues of manufacturing processes. This study was performed to scrutinize optimum parameters and their levels to attain maximum impact strength, flexural strength and tensile strength based on five different FFF process parameters. The algorithm yielded better results than other studies and successfully achieved a maximum response, which may be helpful to enhance the mechanical strength of FFF parts. The study opens a plethora of research prospects for implementing NMRA in manufacturing. Moreover, the findings may help identify critical parametric levels for the fabrication of customized products at the commercial level and help to attain the objectives of Industry 4.0.
Development and Characterization of Polypropylene Waste from Personal Protective Equipment (PPE)-Derived Char-Filled Sugar Palm Starch Biocomposite Briquettes
Authors: Harussani M. M. , Sapuan S. M. , Rashid Umer , Khalina A.
Published: May 2021

Slow pyrolysis using a batch reactor at 450 °C was applied to the polypropylene (PP) powder derived from Coronavirus Disease 2019 (COVID-19) isolation gown waste to yield char briquettes, using sugar palm starch (SPS) and a manual hydraulic press. These studies are significant because of reductions in plastic waste from the preparation of barbecue coal due to environmental sustainability. The results presented here include the physical, morphological, thermal, combustion, and mechanical properties of char when reinforced with various percentages of SPS loadings (0, 10, 20, 30, and 40%), which act as a matrix/binder to produce char/sugar palm starch (C/SPS) composites. The physical and morphological characteristics of C/SPS composites were determined using Fourier transform infrared (FTIR) and field emission scanning electron microscopy (FESEM). On the other hand, the thermal and combustion properties of the C/SPS briquettes were studied via thermogravimetric and bomb calorimeter analysis. The results show that the compressive strength of the briquettes increased as the SPS loading increased, whereas the higher heating values (HHV) reduced. The findings indicate that C-80/SPS-20 briquettes presented excellent combustion characteristics (1,761,430 J/g) with satisfactory mechanical strength (1.463 MPa) in the compression test. Thus, C-80/SPS-20 briquettes are the most suitable composites for domestic and commercial uses.
Current Mental Health Clients’ Attitudes Regarding Religion and Spirituality in Treatment: A National Survey
Authors: Oxhandler Holly K. , Pargament Kenneth I. , Pearce Michelle J. , Vieten Cassandra , Moffatt Kelsey M.
Published: May 2021

Over the last several years, there has been a growing interest in clients’ views toward integrating their religion and spirituality (RS) into mental health treatment. However, most of these studies have been limited to small samples and specific populations, regions, and/or clinical issues. This article describes the first national survey of current mental health clients across the US regarding their attitudes towards integrating their RS in treatment using a revised version of the Religious/Spiritually Integrated Practice Assessment Scale-Client Attitudes, version 2 (RSIPAS-CAv2) with a sample of 989 clients. Our findings indicate mental health clients have overwhelmingly positive attitudes regarding integrating their RS into mental health treatment. Additionally, we explored what background characteristics predict clients’ attitudes toward this area of practice and found the top predictor was their intrinsic religiosity, followed by whether they had previously discussed RS with their current provider, age, gender, organized and non-organized religious activities, belief in God/Higher Power, and frequency of seeing their mental health provider. The reliability and validity of the RSIPAS-CAv2 was also explored and this scale is recommended for future use. Implications and recommendations for practice, research, and future training efforts are discussed.
Mapping Digital Religion: Exploring the Need for New Typologies
Authors: Siuda Piotr
Published: May 2021

Today, it is challenging to separate online and offline spaces and activities, and this is also true of digital religion as online and offline religious spaces become blended or blurred. With this background, the article explores the need for new typologies of what is religious on the Internet and proposes a conceptual framework for mapping digital religion. Four types of that which is religious on the Internet are presented based on influential classification by Helland. He introduced (1) religion online (sites that provide information without interactivity) and (2) online religion (interactivity and participation). Helland’s concept is developed by, among others, adding two types: (3) innovative religion (new religious movements, cults, etc.) and (4) traditional religion (e.g., Christianity or Islam). Each type is illustrated by selected examples and these are a result of a larger project. The examples are grouped into three areas: (1) religious influencers, (2) online rituals and (3) cyber-religions (parody religions). Additionally, the visual frame for mapping digital religion is presented including the examples mentioned. The presented framework attempts to improve Helland’s classification by considering a more dynamic nature of digital religion. The model is just one possible way for mapping digital religion and thus should be developed further. These and other future research threads are characterized.
Trajectory Extrapolation for Manual Robot Remote Welding
Authors: Ebel Lucas Christoph , Maaß Jochen , Zuther Patrick , Sheikhi Shahram
Published: May 2021

This article describes an algorithm for the online extrapolation of hand-motion during remote welding. The aim is to overcome the spatial limitations of the human welder’s arms in order to cover a larger workspace with a continuous weld seam and to substantially relieve the welder from strain and fatigue. Depending on the sampled hand-motion data, an extrapolation of the given motion patterns is achieved by decomposing the input signals in a linear direction and a periodic motion component. An approach to efficiently determine the periodicity using a sampled autocorrelation function and the subsequent application of parameter identification using a spline function are presented in this paper. The proposed approach is able to resemble all practically relevant motion patterns and has been validated successfully on a remote welding system with limited input space and audio-visual feedback by an experienced welder.
Influential Factors in Remote Monitoring of Heart Failure Patients: A Review of the Literature and Direction for Future Research
Authors: Senarath Sashini , Fernie Geoff , Roshan Fekr Atena
Published: May 2021

With new advances in technology, remote monitoring of heart failure (HF) patients has become increasingly prevalent and has the potential to greatly enhance the outcome of care. Many studies have focused on implementing systems for the management of HF by analyzing physiological signals for the early detection of HF decompensation. This paper reviews recent literature exploring significant physiological variables, compares their reliability in predicting HF-related events, and examines the findings according to the monitored variables used such as body weight, bio-impedance, blood pressure, heart rate, and respiration rate. The reviewed studies identified correlations between the monitored variables and the number of alarms, HF-related events, and/or readmission rates. It was observed that the most promising results came from studies that used a combination of multiple parameters, compared to using an individual variable. The main challenges discussed include inaccurate data collection leading to contradictory outcomes from different studies, compliance with daily monitoring, and consideration of additional factors such as physical activity and diet. The findings demonstrate the need for a shared remote monitoring platform which can lead to a significant reduction of false alarms and help in collecting reliable data from the patients for clinical use especially for the prevention of cardiac events.
Identifying Images of Dead Chickens with a Chicken Removal System Integrated with a Deep Learning Algorithm
Authors: Liu Hung-Wei , Chen Chia-Hung , Tsai Yao-Chuan , Hsieh Kuang-Wen , Lin Hao-Ting
Published: May 2021

The chicken industry, in which broiler chickens are bred, is the largest poultry industry in Taiwan. In a traditional poultry house, breeders must usually observe the health of the broilers in person on the basis of their breeding experience at regular times every day. When a breeder finds unhealthy broilers, they are removed manually from the poultry house to prevent viruses from spreading in the poultry house. Therefore, in this study, we designed and constructed a novel small removal system for dead chickens for Taiwanese poultry houses. In the mechanical design, this system mainly contains walking, removal, and storage parts. It comprises robotic arms with a fixed end and sweep-in devices for sweeping dead chickens, a conveyor belt for transporting chickens, a storage cache for storing chickens, and a tracked vehicle. The designed system has dimensions of approximately 1.038 × 0.36 × 0.5 m3, and two dead chickens can be removed in a single operation. The walking speed of the chicken removal system is 3.3 cm/s. In order to enhance the automation and artificial intelligence in the poultry industry, the identification system was used in a novel small removal system. The conditions of the chickens in a poultry house can be monitored remotely by using a camera, and dead chickens can be identified through deep learning based on the YOLO v4 algorithm. The precision of the designed system reached 95.24% in this study, and dead chickens were successfully moved to the storage cache. Finally, the designed system can reduce the contact between humans and poultry to effectively improve the overall biological safety.
Bluetooth 5.1: An Analysis of Direction Finding Capability for High-Precision Location Services
Authors: Pau Giovanni , Arena Fabio , Gebremariam Yonas Engida , You Ilsun
Published: May 2021

This paper presents an in-depth overview of the Bluetooth 5.1 Direction Finding standard’s potentials, thanks to enhancing the Bluetooth Low Energy (BLE) firmware. This improvement allows producers to create location applications based on the Angle of Departure (AoD) and the Angle of Arrival (AoA). Accordingly, it is conceivable to design proper Indoor Positioning Systems (IPS), for instance, for the traceability of resources, assets, and people. First of all, Radio Frequency (RF) radiogoniometry techniques, helpful in calculating AoA and AoD angles, are introduced in this paper. Subsequently, the topic relating to signal direction estimation is deepened. The Bluetooth Core Specification updates concerning version 5.1, both at the packet architecture and prototyping levels, are also reported. Some suitable platforms and development kits for running the new features are then presented, and some basic applications are illustrated. This paper’s final part allows ascertaining the improvement made by this new definition of BLE and possible future developments, especially concerning applications related to devices, assets, or people’s indoor localization. Some preliminary results gathered in a real evaluation scenario are also presented.
Real-Time Measurement of Drilling Fluid Rheological Properties: A Review
Authors: Liu Naipeng , Zhang Di , Gao Hui , Hu Yule , Duan Longchen
Published: May 2021

The accurate and frequent measurement of the drilling fluid’s rheological properties is essential for proper hydraulic management. It is also important for intelligent drilling, providing drilling fluid data to establish the optimization model of the rate of penetration. Appropriate drilling fluid properties can improve drilling efficiency and prevent accidents. However, the drilling fluid properties are mainly measured in the laboratory. This hinders the real-time optimization of drilling fluid performance and the decision-making process. If the drilling fluid’s properties cannot be detected and the decision-making process does not respond in time, the rate of penetration will slow, potentially causing accidents and serious economic losses. Therefore, it is important to measure the drilling fluid’s properties for drilling engineering in real time. This paper summarizes the real-time measurement methods for rheological properties. The main methods include the following four types: an online rotational Couette viscometer, pipe viscometer, mathematical and physical model or artificial intelligence model based on a Marsh funnel, and acoustic technology. This paper elaborates on the principle, advantages, limitations, and usage of each method. It prospects the real-time measurement of drilling fluid rheological properties and promotes the development of the real-time measurement of drilling rheological properties.
Clusters of Spin Valve Sensors in 3D Magnetic Field of a Label
Authors: Babaytsev Georgy V. , Chechenin Nikolay G. , Dzhun Irina O. , Kozin Mikhail G. , Makunin Alexey V. , Romashkina Irina L.
Published: May 2021

Magnetic field sensors based on the giant magnetoresistance (GMR) effect have a number of practical current and future applications. We report on a modeling of the magnetoresistive response of moving spin-valve (SV) GMR sensors combined in certain cluster networks to an inhomogeneous magnetic field of a label. We predicted a large variety of sensor responses dependent on the number of sensors in the cluster, their types of interconnections, the orientation of the cluster, and the trajectory of sensor motion relative to the label. The model included a specific shape of the label, producing an inhomogeneous magnetic field. The results can be used for the optimal design of positioning devices.
Dual-Quaternion Analytic LQR Control Design for Spacecraft Proximity Operations
Authors: Stanfield Kyl , Bani Younes Ahmad
Published: May 2021

Proximity operations offer aggregate capability for a spacecraft operating in close proximity to another spacecraft, to perform on-orbit satellite servicing, or to a space object to perform debris removal. To utilize a spacecraft performing such advanced maneuvering operations and perceiving of the relative motion of a foreign spacecraft, these trajectories must be modeled accurately based on the coupled translational and rotational dynamics models. This paper presents work towards exploiting the dual-quaternion representations of spacecraft relative dynamics for proximity operations and developing a sub-optimal control law for efficient and robust maneuvers. A linearized model using dual-quaternions for the proximity operation was obtained, and its stability was verified using Monte Carlo simulations for the linear quadratic regulator solution. A sub-optimal control law using generalized higher order feedback gains in dual-quaternion form was developed based on small error approximations for the proximity operation and also verified through Monte Carlo simulations. Necessary information needed to understand the theory behind the use of the dual-quaternion is also overviewed within this paper, including the validity of using the dual-quaternions against their Cartesian or quaternion equivalents.
A Joint Low-Rank and Sparse Method for Reference Signal Purification in DTMB-Based Passive Bistatic Radar
Authors: Zuo Luo , Wang Jun , Zhao Te , Cheng Zuhan
Published: May 2021

In a digital terrestrial multimedia broadcasting (DTMB)-based passive bistatic radar (PBR) system, the received reference signal often suffers from serious multipath effect, which decreases the detection ability of low-observable targets in urban environments. In order to improve the target detection performance, a novel reference signal purification method based on the low-rank and sparse feature is proposed in this paper. Specifically, this method firstly performs synchronization operations to the received reference signal and thus obtains the corresponding pseudo-noise (PN) sequences. Then, by innovatively exploiting the inherent low-rank structure of DTMB signals, the noise component in PN sequences is reduced. After that, a temporal correlation (TC)-based adaptive orthogonal matching pursuit (OMP) method, i.e., TC-AOMP, is performed to acquire the reliable channel estimation, whereby the previous noise-reduced PN sequences and a new halting criterion are utilized to improve channel estimation accuracy. Finally, the purification reference signal is obtained via equalization operation. The advantage of the proposed method is that it can obtain superior channel estimation performance and is more efficient compared to existing methods. Numerical and experimental results collected from the DTMB-based PBR system are presented to demonstrate the effectiveness of the proposed method.
Fault Diagnosis and Fault Frequency Determination of Permanent Magnet Synchronous Motor Based on Deep Learning
Authors: Wang Chiao-Sheng , Kao I-Hsi , Perng Jau-Woei
Published: May 2021

The early diagnosis of a motor is important. Many researchers have used deep learning to diagnose motor applications. This paper proposes a one-dimensional convolutional neural network for the diagnosis of permanent magnet synchronous motors. The one-dimensional convolutional neural network model is weakly supervised and consists of multiple convolutional feature-extraction modules. Through the analysis of the torque and current signals of the motors, the motors can be diagnosed under a wide range of speeds, variable loads, and eccentricity effects. The advantage of the proposed method is that the feature-extraction modules can extract multiscale features from complex conditions. The number of training parameters was reduced so as to solve the overfitting problem. Furthermore, the class feature map was proposed to automatically determine the frequency component that contributes to the classification using the weak learning method. The experimental results reveal that the proposed model can effectively diagnose three different motor states—healthy state, demagnetization fault state, and bearing fault state. In addition, the model can detect eccentric effects. By combining the current and torque features, the classification accuracy of the proposed model is up to 98.85%, which is higher than that of classical machine-learning methods such as the k-nearest neighbor and support vector machine.