bluuebunny/crossref_metadata_2025 huggingface dataset:
Near-Infrared Light Irradiation of Porphyrin-Modified Gold Nanoparticles Promotes Cancer-Cell-Specific Cytotoxicity
Authors: Kurokawa Hiromi , Taninaka Atsushi , Yoshitomi Toru , Shigekawa Hidemi , Matsui Hirofumi
Published: February 2022

The use of nanoparticles has been investigated as a new cancer treatment. These can induce specific cytotoxicity in cancer cells. In particular, Au nanoparticles (AuNPs) have unique characteristics. The maximum absorption spectrum of AuNPs can be adjusted to modify their size or shape to absorb near-infrared light that can penetrate into tissue without photodamage. Thus, the combination of AuNPs and near-infrared light can be used to treat cancer in deep-seated organs. To obtain effective cancer-specific accumulation of AuNPs, we focused on porphyrin and synthesized a porphyrin-attached Au compound: Au-HpD. In this study, we investigated whether Au-HpD possesses cancer-specific accumulation and cytotoxicity. Intracellular Au-HpD accumulation was higher in cancer cells than in normal cells. In order to analyze the cytotoxicity induced by Au-HpD, cancer cells and normal cells were co-cultured in the presence of Au-HpD; then, they were subjected to 870 nm laser irradiation. We observed that, after laser irradiation, cancer cells showed significant morphological changes, such as chromatin condensation and nuclear fragmentation indicative of cell apoptosis. This strong effect was not observed when normal cells were irradiated. Moreover, cancer cells underwent cell apoptosis with combination therapy.
Simulation Study on the Defect Generation, Accumulation Mechanism and Mechanical Response of GaAs Nanowires under Heavy-Ion Irradiation
Authors: Jia Tongxuan , Wang Zujun , Tang Minghua , Xue Yuanyuan , Huang Gang , Nie Xu , Lai Shankun , Ma Wuying , He Baoping , Gou Shilong
Published: February 2022

Nanowire structures with high-density interfaces are considered to have higher radiation damage resistance properties compared to conventional bulk structures. In the present work, molecular dynamics (MD) is conducted to investigate the irradiation effects and mechanical response changes of GaAs nanowires (NWs) under heavy-ion irradiation. For this simulation, single-ion damage and high-dose ion injection are used to reveal defect generation and accumulation mechanisms. The presence of surface effects gives an advantage to defects in rapid accumulation but is also the main cause of dynamic annihilation of the surface. Overall, the defects exhibit a particular mechanism of rapid accumulation to saturation. Moreover, for the structural transformation of irradiated GaAs NWs, amorphization is the main mode. The main damage mechanism of NWs is sputtering, which also leads to erosion refinement at high doses. The high flux ions lead to a softening of the mechanical properties, which can be reflected by a reduction in yield strength and Young’s modulus.
Silver Nanoparticle Arrays onto Glass Substrates Obtained by Solid-State Thermal Dewetting: A Morphological, Structural and Surface Chemical Study
Authors: Badán Juan Agustín , Navarrete-Astorga Elena , Henríquez Rodrigo , Jiménez Francisco Martín , Ariosa Daniel , Ramos-Barrado José Ramón , Dalchiele Enrique A.
Published: February 2022

Silver nanoparticles (NPs) on glass substrates were obtained by a solid-state thermal dewetting (SSD) process using vacuum-evaporated-silver precursor layers. An exhaustive investigation of the morphological, structural, and surface chemistry properties by systematically controlling the precursor film thickness, annealing temperature, and time was conducted. Thin silver films with thicknesses of 40 and 80 nm were deposited and annealed in air by applying a combined heat-up+constant temperature–time program. Temperatures from 300 to 500 °C and times from 0 to 50 min were assayed. SSD promoted the morphological modification of the films, leading to the Ag NPs having a discrete structure. The size, shape, surface density, and inter-nanoparticle distance of the nanoparticles depended on the initial film thickness, annealing temperature, and time, exhibiting a cubic silver structure with a (111) preferred crystallographic orientation. The prepared NPs were found to be highly enriched in the Ag{111}/Ag{110}/Ag{100} equilibrium facets. SSD not only promotes NP formation but also promotes the partial oxidation from Ag to AgO at the surface level. AgO was detected on the surface around the nanoparticles synthesized at 500 °C. Overall, a broad framework has been established that connects process factors to distinguish resultant Ag NP features in order to develop unique silver nanoparticles for specific applications.
Double Perovskite LaFe1−xNixO3 Coated with Sea Urchin-like Gold Nanoparticles Using Electrophoresis as the Photoelectrochemical Electrode to Enhance H2 Production via Surface Plasmon Resonance Effect
Authors: Tsai Hsiang-Wei , Su Yen-Hsun
Published: February 2022

The surface plasmon resonance (SPR) effect and the hetero-junction structure play crucial roles in enhancing the photocatalytic performances of catalysts for the water-splitting reaction. In this study, a series of double perovskites LaFe1−xNixO3 was synthesized. LaFe1−xNixO3 particles were then decorated with sea urchin-like Au nanoparticles (NPs) with the average size of approximately 109.83 ± 8.48 nm via electrophoresis. The d-spacing became narrow and the absorption spectra occurred the redshift phenomenon more when doping increasing Ni mole concentrations for the raw LaFe1−xNixO3 samples. From XPS analysis, the Ni atoms were inserted into the lattice of the matrix, resulting in the defect of the oxygen vacancy, and NiO and Fe2O3 were formed. This hybrid structure was the ideal electrode for photoelectrochemical hydrogen production. The photonic extinction of the Au-coated LaFe1−xNixO3 was less than 2.1 eV (narrow band gap), and the particles absorbed more light in the visible region. According to the Mott–Schottky plots, all the LaFe1−xNixO3 samples were the n-type semiconductors. Moreover, all the band gaps of the Au-coated LaFe1−xNixO3 samples were higher than 1.23 eV (H+/H2). Then, the hot electrons from the Au NPs were injected via the SPR effect, the coupling effect between LaFe1−xNixO3 and Au NPs, and the more active sites from Au NPs into the conduction band of the semiconductor, improving the hydrogen efficiency. The H2 efficiency of the Au-coated LaFe1−xNixO3 measured in ethanol was approximately ten times larger than the that of Au-coated LaFe1−xNixO3 measured in 1-butanol at any testing temperature because ohmic and kinetic losses occurred in the latter solvent. Thus, the activation energies of ethanol at any testing temperature were smaller. The maximum real H2 production was up to 43,800 μmol g−1 h−1 in ethanol. The redox reactions among metal ions, OH*, and oxides were consecutively proceeded under visible light illumination.
Inhibition of Influenza Virus Replication by Oseltamivir Derivatives
Authors: Chan Renee , Tao Kin , Ye Jiqing , Lui Kevin , Yang Xiao , Ma Cong , Chan Paul
Published: February 2022

Characterized by the high morbidity and mortality and seasonal surge, the influenza virus (IV) remains a major public health challenge. Oseltamivir is commonly used as a first-line antiviral. As a neuraminidase inhibitor, it attenuates the penetration of viruses through the mucus on the respiratory tract and inhibits the release of virus progeny from infected cells. However, over the years, oseltamivir-resistant strains have been detected in the IV surveillance programs. Therefore, new antivirals that circumvent the resistant strains would be of great importance. In this study, two novel secondary amine derivatives of oseltamivir CUHK326 (6f) and CUHK392 (10i), which bear heteroaryl groups of M2-S31 proton channel inhibitors, were designed, synthesized and subjected to biological evaluation using plaque assay. Influenza A virus (A/Oklahoma/447/2008, H1N1), influenza B viruses (B/HongKong/CUHK33261/2012), an oseltamivir-resistant influenza A virus (A/HongKong/CUHK71923/2009, H1N1) and an oseltamivir-resistant influenza B virus (B/HongKong/CUHK33280/2012) were included in the antiviral effect assessment compared to oseltamivir carboxylate (OC). Both novel compounds significantly reduced the plaque size of seasonal IV A and B, and performed similarly to OC at their corresponding half-maximal inhibitory concentration (IC50). CUHK392 (10i) functioned more effectively than CUHK326 (6f). More importantly, these compounds showed an inhibitory effect on the oseltamivir-resistant strain under 10 nM with selective index (SI) of >200.
The pH Effects on SARS-CoV and SARS-CoV-2 Spike Proteins in the Process of Binding to hACE2
Authors: Xie Yixin , Guo Wenhan , Lopez-Hernadez Alan , Teng Shaolei , Li Lin
Published: February 2022

COVID-19 has been threatening human health since the late 2019, and has a significant impact on human health and economy. Understanding SARS-CoV-2 and other coronaviruses is important to develop effective treatments for COVID-19 and other coronavirus-caused diseases. In this work, we applied multi-scale computational approaches to study the electrostatic features of spike (S) proteins for SARS-CoV and SARS-CoV-2. From our results, we found that SARS-CoV and SARS-CoV-2 have similar charge distributions and electrostatic features when binding with the human angiotensin-converting enzyme 2 (hACE2). Energy pH-dependence calculations revealed that the complex structures of hACE2 and the S proteins of SARS-CoV/SARS-CoV-2 are stable at pH values ranging from 7.5 to 9. Three independent 100 ns molecular dynamics (MD) simulations were performed using NAMD to investigate the hydrogen bonds between S proteins RBD and hACE2 RBD. From MD simulations, we found that SARS-CoV-2 forms 19 pairs (average of three simulations) of hydrogen bonds with high occupancy (>50%) to hACE2, compared to 16 pairs between SARS-CoV and hACE2. Additionally, SARS-CoV viruses prefer sticking to the same hydrogen bond pairs, while SARS-CoV-2 tends to have a larger range of selections on hydrogen bonds acceptors. We also labelled key residues involved in forming the top five hydrogen bonds that were found in all three independent 100 ns simulations. This identification is important to potential drug designs for COVID-19 treatments. Our work will shed the light on current and future coronavirus-caused diseases.
Performance of Surface Plasmon Resonance Sensors Using Copper/Copper Oxide Films: Influence of Thicknesses and Optical Properties
Authors: Barchiesi Dominique , Gharbi Tasnim , Cakir Deniz , Anglaret Eric , Fréty Nicole , Kessentini Sameh , Maâlej Ramzi
Published: February 2022

Surface plasmon resonance sensors (SPR) using copper for sensitive parts are a competitive alternative to gold and silver. Copper oxide is a semiconductor and has a non-toxic nature. The unavoidable presence of copper oxide may be of interest as it is non-toxic, but it modifies the condition of resonance and the performance of the sensor. Therefore, the characterization of the optical properties of copper and copper oxide thin films is of interest. We propose a method to recover both the thicknesses and optical properties of copper and copper oxide from absorbance curves over the (0.9;3.5) eV range, and we use these results to numerically investigate the surface plasmon resonance of copper/copper oxide thin films. Samples of initial copper thicknesses 10, 30 and 50 nm, after nine successive oxidations, are systematically studied to simulate the signal of a Surface Plasmon Resonance setup. The results obtained from the resolution of the inverse problem of absorbance are used to discuss the performance of a copper-oxide sensor and, therefore, to evaluate the optimal thicknesses.
High Power and Efficient 4.43 μm BaGa4Se7 Optical Parametric Oscillator Pumped at 1064 nm
Authors: Kang Minqiang , Deng Ying , Yao Jiyong , Zhu Qihua
Published: February 2022

A high power and efficiency mid-infrared optical parametric oscillator based on a BaGa4Se7 crystal is demonstrated in this paper. It was pumped by a 500 Hz Q-switched Nd:YAG laser at room temperature. Without cooling, up to 0.76 W output power at 4.43 μm was generated with respect to the incident pump power (1064 nm) of 5.52 W, corresponding to an optical-to-optical conversion efficiency of 13.7%. The corresponding slope efficiency was as high as 18.7%. The pulse width of the signal wave was 5.2 ns at the pump pulse of 13.7 ns. To the best of our knowledge, this is to date the highest output power achieved at 4–5 μm from a 1064 nm pumped BGSe OPO laser. Considering that no additional cooling system was applied, this work provides a good solution for a high-efficient, compact or even portable mid-infrared solid-state laser device.
Aqueous Extracts of Three Herbs Allelopathically Inhibit Lettuce Germination but Promote Seedling Growth at Low Concentrations
Authors: Wang Kaili , Wang Ting , Ren Cheng , Dou Pengpeng , Miao Zhengzhou , Liu Xiqiang , Huang Ding , Wang Kun
Published: February 2022

Allelopathy is an important process in plant communities. The effects of allelopathy on seed germination and seedling development have been extensively investigated. However, the influences of extract soaking time and concentration on the foregoing parameters are poorly understood. Here, we conducted a seed germination assay to determine the allelopathic effects of the donor herbs Achnatherum splendens (Trin.) Nevski, Artemisia frigida Willd., and Stellera chamaejasme L., from a degraded grassland ecosystem in northern China, on lettuce (Lactuca sativa L.) seed germination and early seedling growth. Extract soaking times (12 h or 24 h) did not exhibit significantly different effects on lettuce seed germination or seedling development. However, all aqueous herb extracts inhibited lettuce seed germination and root length (RI < 0) and promoted lettuce shoot length, stem length, leaf length, and leaf width (RI > 0) at both low (0.005 g mL−1) and high (0.05 g mL−1) concentrations. Moreover, A. splendens extracts increased seedling biomass (RI > 0) and synthetical allelopathic effect (SE > 0) at both concentrations. In contrast, both A. frigida and S. chamaejasme extracts had hormesis effects, which stimulate at low concentrations (RI > 0) but inhibit at high concentrations (RI < 0) on seedling biomass and synthetical allelopathic effect (SE). The results suggest that allelopathic potential may be an important mechanism driving the dominance of A. frigida and S. chamaejasme in degraded grasslands. Reseeding allelopathy-promoting species such as A. splendens may be beneficial to grassland restoration. The present study also demonstrated that seedling biomass, root and shoot length, and seed germination rate are the optimal bioindicators in allelopathy assays and could be more representative when they are combined with the results of multivariate analyses.
Exploring Breakthroughs in Three Traits Belonging to Seed Life
Authors: Matilla Angel J.
Published: February 2022

Based on prior knowledge and with the support of new methodology, solid progress in the understanding of seed life has taken place over the few last years. This update reflects recent advances in three key traits of seed life (i.e., preharvest sprouting, genomic imprinting, and stored-mRNA). The first breakthrough refers to cloning of the mitogen-activated protein kinase-kinase 3 (MKK3) gene in barley and wheat. MKK3, in cooperation with ABA signaling, controls seed dormancy. This advance has been determinant in producing improved varieties that are resistant to preharvest sprouting. The second advance concerns to uniparental gene expression (i.e., imprinting). Genomic imprinting primarily occurs in the endosperm. Although great advances have taken place in the last decade, there is still a long way to go to complete the puzzle regarding the role of genomic imprinting in seed development. This trait is probably one of the most important epigenetic facets of developing endosperm. An example of imprinting regulation is polycomb repressive complex 2 (PRC2). The mechanism of PRC2 recruitment to target endosperm with specific genes is, at present, robustly studied. Further progress in the knowledge of recruitment of PRC2 epigenetic machinery is considered in this review. The third breakthrough referred to in this update involves stored mRNA. The role of the population of this mRNA in germination is far from known. Its relations to seed aging, processing bodies (P bodies), and RNA binding proteins (RBPs), and how the stored mRNA is targeted to monosomes, are aspects considered here. Perhaps this third trait is the one that will require greater experimental dedication in the future. In order to make progress, herein are included some questions that are needed to be answered.
Interaction between Growth Regulators Controls In Vitro Shoot Multiplication in Paulownia and Selection of NaCl-Tolerant Variants
Authors: Salem Jehan , Hassanein Ahmed , El-Wakil Deiaa A. , Loutfy Naglaa
Published: February 2022

The interaction between cytokinin, auxin and GA controlled in vitro shoot multiplication in paulownia was influenced by a medium water potential (Ψ) modulation, where it was modulated using different textures or strengths of MS medium, media of different types (MS, WPM, SH and B5) or NaCl incorporation. The interaction between 2 mg/L BAP and 0.1 mg/L NAA expressed the highest shoot number on each media type, but it was better with media of lower water potential (MS and WPM), and MS medium was the best. Ψ of full-strength semisolid MS medium expressed the highest shoot multiplication. The opposite was detected when Ψ of MS medium was changed using half- or double-strength MS. Ψ of full-strength MS medium in semisolid form resulted in a valuable interaction between 2 mg/L BAP, 0.1 mg/L NAA and 0.1 mg/L GA, leading to efficient shoot formation, and it was associated with an increase in internode length and decrease in stem diameter, which facilitated obtaining synseeds with a high ability to convert. High genetic variation was recorded under long-term culture (14 subcultures). Polymorphism using the ISSR technique was higher than that of RAPD. A further increase in polymorphism was detected when NaCl was used, where five salt-tolerant lines were selected. Some salt-tolerant-selected lines showed one or more amplification products of a specific molecular weight that did not appear in the control. For example, with OPA-07 and OPG-02 RAPD primers, all the salt-tolerant-selected lines showed the appearance of amplification fragments (610 bp and 300 bp, respectively) that were not detected in control.
Impact of Single and Combined Salinity and High-Temperature Stresses on Agro-Physiological, Biochemical, and Transcriptional Responses in Rice and Stress-Release
Authors: Nahar Lutfun , Aycan Murat , Hanamata Shigeru , Baslam Marouane , Mitsui Toshiaki
Published: February 2022

Here, for the first time, we aimed to identify in rice the key mechanisms and processes underlying tolerance to high-temperature (HT) or salt stress (SS) alone, the co-occurrence of both stresses, and recovery using physiological and biochemical measurements and gene expression analysis. We also investigated whether recovery from the two stressors depended on the relative intensities/relief of each stressor. Wild type (‘Yukinkomai’) rice plants were found to be more susceptible to salinity or heat applied individually. SS leads to a depletion of cellular water content, higher accumulation of Na+, and alterations in photosynthetic pigments. The stress-tolerant cultivar ‘YNU31-2-4’ (YNU) displayed a lower Na+/K+ ratio, higher water content in cells and improved photosynthetic traits, antioxidant system, and expression of defence genes. Strikingly, the SS + HT combination provided a significant level of protection to rice plants from the effects of SS alone. The expression pattern of a selected set of genes showed a specific response and dedicated pathways in plants subjected to each of the different stresses, while other genes were explicitly activated when the stresses were combined. Aquaporin genes were activated by SS, while stress-related (P5CS, MSD1, HSPs, and ions transporters) genes were shaped by HT. Hierarchical clustering and principal component analyses showed that several traits exhibited a gradually aggravating effect as plants were exposed to the combined stresses and identified heat as a mitigating factor, clearly separating heat + salt-stressed from salt-non-heat-stressed plants. Furthermore, seedling recovery was far more dependent on the relative intensities of stressors and cultivars, demonstrating the influence of one stressor over another upon stress-release. Taken together, our data show the uniqueness and complexity of the physiological and molecular network modules used by rice plants to respond to single and combined stresses and recovery.
Morphological, Molecular Identification and Pathogenicity of Neoscytalidium dimidiatum Causing Stem Canker of Hylocereus polyrhizus in Southern Thailand
Authors: Dy Kim Sreang , Wonglom Prisana , Pornsuriya Chaninun , Sunpapao Anurag
Published: February 2022

Red-fleshed dragon fruit (Hylocereus polyrhizus) is commonly cultivated in Thailand, especially in southern Thailand, where the weather favors plant growth and development. In 2021, stem canker of H. polyrhizus was observed in a dragon fruit plantation field in Phatthalung Province, southern Thailand. Small, orange circular spots developed on the stem of H. polyrhizus, which later became gray, and the lesion expanded with a mass of conidia. Scytalidium-like fungus was isolated from infected tissues. Based on morphology and phylogenetic analyses of internal transcribed spacer (ITS), nuclear large subunit (LSU) and β-tubulin (tub) sequences of fungal isolates, the fungus was identified as Neoscytalidium dimidiatum. Pathogenicity tests revealed that this isolate caused stem canker on the stem of H. polyrhizus, similar to that observed in the field. Knowledge of the diagnosis of plant diseases is an important step for managing plant diseases and therefore, this finding provides basic information for the development of appropriate strategies to manage stem canker disease on H. polyrhizus plants.
The Optical Response of a Mediterranean Shrubland to Climate Change: Hyperspectral Reflectance Measurements during Spring
Authors: Mevy Jean-Philippe , Biryol Charlotte , Boiteau-Barral Marine , Miglietta Franco
Published: February 2022

Remote sensing techniques in terms of monitoring plants’ responses to environmental constraints have gained much attention during recent decades. Among these constraints, climate change appears to be one of the major challenges in the Mediterranean region. In this study, the main goal was to determine how field spectrometry could improve remote sensing study of a Mediterranean shrubland submitted to climate aridification. We provided the spectral signature of three common plants of the Mediterranean garrigue: Cistus albidus, Quercus coccifera, and Rosmarinus officinalis. The pattern of these spectra changed depending on the presence of a neighboring plant species and water availability. Indeed, the normalized water absorption reflectance (R975/R900) tended to decrease for each species in trispecific associations (11–26%). This clearly indicates that multispecific plant communities will better resist climate aridification compared to monospecific stands. While Q. coccifera seemed to be more sensible to competition for water resources, C. albidus exhibited a facilitation effect on R. officinalis in trispecific assemblage. Among the 17 vegetation indices tested, we found that the pigment pheophytinization index (NPQI) was a relevant parameter to characterize plant–plant coexistence. This work also showed that some vegetation indices known as indicators of water and pigment contents could also discriminate plant associations, namely RGR (Red Green Ratio), WI (Water Index), Red Edge Model, NDWI1240 (Normalized Difference Water Index), and PRI (Photochemical Reflectance Index). The latter was shown to be linearly and negatively correlated to the ratio of R975/R900, an indicator of water status.
Effect of Electrode Profile and Polarity on Performance of Pressurized Sparkgap Switch
Authors: Gandi Vinod Kumar , Verma Rishi , Warrier Manoj , Sharma Archana
Published: February 2022

Sparkgap are most widely used closing switches in various high-voltage pulsed power systems and its reliable operation at desired voltage level is very essential. Conventionally by adjusting the filling gas pressure inside sparkgap switch, breakdown voltage level is altered but switching characteristics such as stability in hold-off voltage at various pressures, breakdown delay, plasma channel formation, and erosion rate are mainly dictated by adopted electrode profile and its dimensions, inter-electrode gap length and polarity. In this paper, experimental results obtained on breakdown characteristics of four different electrode geometries—Plane Parallel, Hemi-spherical, Bruce, and Rogowski and also a generalized criterion for fixing major dimensions of electrode and inter-gap length to ensure uniform electric field in the inter-electrode region are reported. All electrodes are of brass material and have common radius and thickness of 25 mm and 18 mm, respectively (surface finish <1 µm). Experiments performed on various electrode profiles in gap lengths of 2 mm to 5 mm range with pure nitrogen (N2) gas pressurization up to 50 psi reveal that among all profiles, Rogowski performs most reliably having stable hold-off voltage in wide operating range. Hold-off voltage magnitude and breakdown delay was commonly obtained higher for negative polarity in all trials. A comprehensive overview of experimental investigation reported herein compares suitability of various electrode profiles and polarity for reliable switching.
Uncertain Operating Conditions Implications on Multistage Operations Optimal Design and Environmental Impact
Authors: Di Pretoro Alessandro , Joulia Xavier , Manenti Flavio , Montastruc Ludovic
Published: February 2022

Energy demand is increasingly the most relevant cost item in chemical plants. Operating expenses indeed play a main role in all plants processing large amounts of feedstock via well-established processes in the petrochemical industry. In staged operations, the optimal number of stages is usually obtained by means of an economic optimization. However, the designed equipment, external duties, and thus operating expenses may considerably vary under the effect of external disturbances. The main purpose of this paper is to outline a simple but effective procedure to account for perturbations in the assessment of the optimal number of stages. The analysis shows that appropriate investments could lead to a unit design able to mitigate the higher duty requirements when external perturbations occur. The results highlight that the optimal number of stages varies when uncertainty is considered and, with low computational effort, this can be effectively quantified by means of the applied methodology. Furthermore, the same approach has been applied to sustainability indicators over the uncertain domain as well. In those cases, when more stages correspond to more flexible equipment, the environmental impact is positively affected, and a double benefit can be observed.
A Numerical Research on the Relationship between Aeolian Sand Ripples and the Sand Flux
Authors: Huo Xinghui , Huang Ning , Zhang Jie
Published: February 2022

Theoretically, the sand flux will not change after the wind-driven sand particle transport reaches the saturated state. However, it has been found in many wind-tunnel experiments that the sand flux will gradually decrease with time in long-term particle transport duration and will eventually reach a new stable state. In this work, we used numerical simulations to study the source of this kind of decrease and found it is caused by the sand ripple on the bed surface. The ripple index showed a strong correlation to the sand flux, and it decreased during the initial stage of the ripple formation. With a simplified theoretical model, we found the linear relationship between the Shields number and the particle transport load holds. However, the slope of this relationship and the dynamic threshold of particle entrainment decreased with the ripple index. As the sand flux scales linearly with the particle transport load, we finally derived an expression that describes how the sand flux on the ripple bedform varies with the wind strength. From this expression, we found the sand flux increases with ripple index, and it was easier to be influenced by the ripple bed form in small wind strength.
Control System of Liquid Fertilizer Variable-Rate Fertilization Based on Beetle Antennae Search Algorithm
Authors: Bai Jinbin , Tian Min , Li Jiangquan
Published: February 2022

In order to solve the problems of low precision of variable-rate fertilization and uneven fertilization flow of field liquid fertilizer applicator, a control system of variable-rate fertilization of liquid fertilizer based on beetle antennae search algorithm was proposed. First of all, this study established a mathematical model for the variable-rate fertilization control system of liquid fertilizer. Then, according to the control requirements, the search algorithm is used to optimize the three parameters of Proportion Integration Differentiation (PID). Finally, the response time and overshoot of the system are analyzed by software simulation, and the PID control based on beetle antennae search algorithm is compared and analyzed with fuzzy PID control and traditional PID control. The control effect of the control system is verified by a bench test. The results show that the actual response time of the variable-rate fertilization control system based on the beetle antennae search algorithm can reach 2 s, and the average relative error can reach 1.27%. Therefore, the control system of this study can achieve a better control effect, and the control method of this study provides a feasible scheme for the study of variable-rate fertilization.
Full-Arch, Implant-Fixed Complete Dentures in Monolithic Zirconia and Titanium: A Digital Workflow to Maximize Cost Effectiveness
Authors: Noè Gaetano , Toffoli Andrea , Bonfiglioli Roberto , Macaluso Guido Maria , Manfredi Edoardo
Published: February 2022

Different techniques can be used to design and manufacture a full-arch, implant-supported prosthesis, and different materials can be chosen for its production, each with its advantages and limitations. One of the possibilities provided by digital tools is their ability to maintain low costs to give more patients the chance to choose this commonly expensive treatment. The present work aims to present a protocol for the realization of full-arch, implant-fixed complete dentures (IFCDs) in monolithic zirconia and titanium. When the analogic master model is obtained, it is scanned to perform the digital wax-up, and the two parts of the prosthesis—a bar in titanium and an aesthetic component in monolithic zirconia—are milled. The dental team must then verify the precision of the milled components on the master model, so that they can be cemented together and delivered to the patient. This technique offers different advantages, in terms of cost sustainability, minimal wear risk for the prosthesis and its antagonists, and ease of re-intervening in the case of complications. The main limitations of the technique may lie in the aesthetic needs of the patient, because of the relatively poor aesthetic performance of monolithic zirconia and the absence of a pink orthopedic component.
Molecular Dynamics Study of Citrullinated Proteins Associated with the Development of Rheumatoid Arthritis
Authors: Taldaev Amir , Rudnev Vladimir , Kulikova Liudmila , Nikolsky Kirill , Efimov Alexander , Malsagova Kristina , Kaysheva Anna
Published: February 2022

Biological activity regulation by protein post-translational modification (PTM) is critical for cell function, development, differentiation, and survival. Dysregulation of PTM proteins is present in various pathological conditions, including rheumatoid arthritis (RA). RA is a systemic autoimmune disease that primarily affects joints, and there are three main types of protein PTMs associated with the development of this disease, namely, glycosylation, citrullination, and carbamylation. Glycosylation is important for the processing and presentation of antigen fragments on the cell surface and can modulate immunoglobulin activity. The citrullination of autoantigens is closely associated with RA, as evidenced by the presence of antibodies specific to citrullinated proteins in the serum of patients. Carbamylation and dysregulation have recently been associated with RA development in humans.In this study, we performed an overview analysis of proteins with post-translational modifications associated with the development of RA adverted in peer-reviewed scientific papers for the past 20 years. As a result of the search, a list of target proteins and corresponding amino acid sequences with PTM in RA was formed. Structural characteristics of the listed modified proteins were extracted from the Protein Data Bank. Then, molecular dynamics experiments of intact protein structures and corresponding structures with PTMs were performed regarding structures in the list announced in the ProtDB service. This study aimed to conduct a molecular dynamics study of intact proteins and proteins, including post-translational modification and protein citrullination, likely associated with RA development. We observed another exhibition of the fundamental physics concept, symmetry, at the submolecular level, unveiled as the autonomous repetitions of outside the protein structural motif performance globule corresponding to those in the whole protein molecule.
Trajectories of Resilience in University Inductees following Outdoor Adventure (OA) Residential Programmes
Authors: Allan John F. , McKenna Jim
Published: February 2022

Even before COVID-19, university inductees were vulnerable to transitional stressors, which impact upon their psychological well-being and ability to complete their studies. Resilience, as a psychological construct, may be analogous to holding the functioning that supports higher-level academic performance in twenty-first century higher education (HE). Given the significant investment HE requires, coupled with students’ capacity to develop their resilience, universities may be expected to promote psychological resilience in new students. Linking HE to resilience, outdoor adventure (OA) residential programmes have enabled inductees to build components of resilience (i.e., increased self-perception, feelings of control, and intrapersonal relationships) that may heighten their immediate and longer-term academic performance. Yet, few studies have examined the sustainability of these effects. Across five annual cohorts, the self-perceived resilience of 2500 inductees was profiled across three time-point trajectories: (i) pre-OA programme, (ii) post-OA programme, and (iii) three months post-OA programme. Further, the functionality of inductees’ enduring resilience was evaluated for predicting their prospective academic performance at the end of their first year of study. Students’ self-perceived resilience, well-being, and positive recollection of OA experiences reflected their bounce-back ability and a healthy trajectory of productive functioning. Students reporting higher levels of resilience after three months of following the programme were more likely to achieve better prospective academic outcomes. The large sample size ensured that a powerful detection of change was established across time. However, given the absence of a comparison condition across all time points, any lasting improvements in students’ resilience was unable to be attributed to the OA programme. Nonetheless, the results give significant grounds for further research in this direction, including the study of more distinct narrative enquiries at follow-up. In this way, pedagogical practices, supporting effective interventions, may be deployed with incoming students, with the aim of building and maintaining students’ on-going resilience across different learning contexts.
“(Not) Her Husband”: Hosea’s God and Ricoeur’s Hermeneutics of Suspicion and Trust
Authors: Hadjiev Tchavdar S.
Published: February 2022

Hosea’s reception history shows the existence of two distinct interpretative traditions in relation to the metaphor “God is a husband” employed in the first three chapters of the book. Many commentators, reading with the grain, focus on the unfaithfulness of Israel, the justice of her punishment and the love of God. More recently, feminist scholars have highlighted the problematic nature of this metaphor since it glorifies maleness and normalises gender–based violence against women. At first glance, these two approaches seem contradictory and mutually exclusive. However, Ricoeur’s discussion of the “conflict of interpretations” provides a fruitful way forward in dealing with this contradiction. Rather than being incompatible with one another, feminist and androcentric interpretations of Hosea are a particular example of the dialectical tension and integration of the hermeneutics of trust and the hermeneutics of suspicion. Both play a vital role in the reading process. One unmasks the idols produced by the false consciousness of the ego, the other opens oneself to hearing the voice of the Sacred, which comes into the text from beyond the realms of language.
Modeling and Analysis of a High-Speed Adjustable Grasping Robot Controlled by a Pneumatic Actuator
Authors: Ohara Kenichi , Iwazawa Ryosuke , Kaneko Makoto
Published: February 2022

This paper discusses the modeling and analysis of a high-speed adjustable grasping robot controlled by a pneumatic actuator. The robot is composed of two grippers, two wires for connecting a pneumatic cylinder and an arm with gripper joints with a spring as well as two stoppers for controlling the gripper stopping point with a brake. By supplying pressurized air into the pneumatic cylinder, the two grippers move forward together with the arm and capture the object by adjusting the air pressure in the cylinder. After capturing the target object, the system can release the object by changing the pressure air in the air cylinder using another port. By considering the state equation of the air, we obtain a dynamic model of the robot, including the actuator. Through numerical simulation, we show that the simulation results can explain the experimental results from the developed robot system. Through our experiments, we confirm that the developed high-speed grasping robot can grasp continuously moving objects with a gap of ±15 mm at 300 mm/s.
A Survey of NOMA for VLC Systems: Research Challenges and Future Trends
Authors: Sadat Hesham , Abaza Mohamed , Mansour Ali , Alfalou Ayman
Published: February 2022

Visible light communication (VLC) has become a promising technology for high data rate communications and an attractive complementary to conventional radio frequency (RF) communication. VLC is a secure, energy efficient and cost-effective technology that exploits the existing infrastructure, particularly in indoor environments, for wireless data transmission. Nevertheless, the main limitation of developing high data rate VLC links is the narrow modulation bandwidth of light-emitting diodes (LEDs), which is in the megahertz range. The power domain nonorthogonal multiple access (PD-NOMA) scheme is envisioned to address several challenges in VLC systems. In this paper, we present a detailed overview of PD-NOMA based VLC systems. Moreover, we introduce insights on some PD-NOMA VLC system constraints and challenges such as power allocation, clipping effect, MIMO and security. Finally, we provide open research problems as well as possible directions for future research to pave the way for the implementation of PD-NOMA VLC systems.
Dynamic Heterogeneous User Generated Contents-Driven Relation Assessment via Graph Representation Learning
Authors: Huang Ru , Chen Zijian , He Jianhua , Chu Xiaoli
Published: February 2022

Cross-domain decision-making systems are suffering a huge challenge with the rapidly emerging uneven quality of user-generated data, which poses a heavy responsibility to online platforms. Current content analysis methods primarily concentrate on non-textual contents, such as images and videos themselves, while ignoring the interrelationship between each user post’s contents. In this paper, we propose a novel framework named community-aware dynamic heterogeneous graph embedding (CDHNE) for relationship assessment, capable of mining heterogeneous information, latent community structure and dynamic characteristics from user-generated contents (UGC), which aims to solve complex non-euclidean structured problems. Specifically, we introduce the Markov-chain-based metapath to extract heterogeneous contents and semantics in UGC. A edge-centric attention mechanism is elaborated for localized feature aggregation. Thereafter, we obtain the node representations from micro perspective and apply it to the discovery of global structure by a clustering technique. In order to uncover the temporal evolutionary patterns, we devise an encoder–decoder structure, containing multiple recurrent memory units, which helps to capture the dynamics for relation assessment efficiently and effectively. Extensive experiments on four real-world datasets are conducted in this work, which demonstrate that CDHNE outperforms other baselines due to the comprehensive node representation, while also exhibiting the superiority of CDHNE in relation assessment. The proposed model is presented as a method of breaking down the barriers between traditional UGC analysis and their abstract network analysis.
Handheld Magnetic-Compliant Gamma-Ray Spectrometer for Environmental Monitoring and Scrap Metal Screening
Authors: Carminati Marco , Di Vita Davide , Morandi Giuseppe , D’Adda Ilenia , Fiorini Carlo
Published: February 2022

Spotting radioactive material in waste is of paramount importance for environment protection. This is particularly challenging when orphan sources are hidden in scrap metal that shields their activity from the traditional detectors in the portals scanning incoming trucks. In order to address this issue, we present a wireless and compact SiPM-based gamma spectrometer compatible with strong magnetic fields (0.1 T) to be installed in the bore of the lifting electromagnets to scan reduced volumes of metal and thus achieve higher sensitivity. The microcontroller-based instrument provides 11% energy resolution (at 662 keV), an energy range from 60 keV to 1.5 MeV, a max. count rate of 30 kcps, a weight <1 kg, and a power consumption <1 W. The results of its extensive characterization in the laboratory and its validation in the field, including operation in a scrap yard as well as on a drone, are reported.
Emotional Speech Recognition Using Deep Neural Networks
Authors: Trinh Van Loan , Dao Thi Le Thuy , Le Xuan Thanh , Castelli Eric
Published: February 2022

The expression of emotions in human communication plays a very important role in the information that needs to be conveyed to the partner. The forms of expression of human emotions are very rich. It could be body language, facial expressions, eye contact, laughter, and tone of voice. The languages of the world’s peoples are different, but even without understanding a language in communication, people can almost understand part of the message that the other partner wants to convey with emotional expressions as mentioned. Among the forms of human emotional expression, the expression of emotions through voice is perhaps the most studied. This article presents our research on speech emotion recognition using deep neural networks such as CNN, CRNN, and GRU. We used the Interactive Emotional Dyadic Motion Capture (IEMOCAP) corpus for the study with four emotions: anger, happiness, sadness, and neutrality. The feature parameters used for recognition include the Mel spectral coefficients and other parameters related to the spectrum and the intensity of the speech signal. The data augmentation was used by changing the voice and adding white noise. The results show that the GRU model gave the highest average recognition accuracy of 97.47%. This result is superior to existing studies on speech emotion recognition with the IEMOCAP corpus.
Integrated Timing of Stroking, Breathing, and Kicking in Front-Crawl Swimming: A Novel Stroke-by-Stroke Approach Using Wearable Inertial Sensors
Authors: Fantozzi Silvia , Coloretti Vittorio , Piacentini Maria Francesca , Quagliarotti Claudio , Bartolomei Sandro , Gatta Giorgio , Cortesi Matteo
Published: February 2022

Quantitative evaluation of synergic action among the different body segments is fundamental to swimming performance. The aim of the present study was to develop an easy-to-use tool for stroke-by-stroke evaluation of a swimmer’s integrated timing of stroking, kicking, and breathing. Twelve swimmers were evaluated during one trial of 100 m front-crawl swimming at self-selected speed. Five three-axial inertial sensors were mounted on the head, wrists, and ankles. Algorithms for the wrist entry into the water, the lower limb beat during the downward action, and the exit/entry of the face from/into the water were developed. Temporal events identified by video-based technique, using one sagittal moving camera, were assumed as the gold standard. The performance was evaluated in terms of the root-mean-square error, 90th percentile of absolute error, coefficient of variation, Bland–Altman plots, and correlation analysis. Results of all temporal events showed high agreement with the gold standard, confirmed by a root-mean-square error of less than 0.05 s for absolute temporal parameters and less than 0.7% for the percentages of the stroke cycle duration, and with correlation coefficients higher than 0.856. The protocol proposed was not only accurate and reliable, but also user-friendly and as unobtrusive as possible for the swimmer, allowing a stroke-by-stroke analysis during the training session.
Nonlinear Intelligent Control of Two Link Robot Arm by Considering Human Voluntary Components
Authors: Deng Mingcong , Kubota Shotaro , Xu Yuanhong
Published: February 2022

This paper proposes a nonlinear intelligent control of a two link robot arm by considering human voluntary components. In general, human arm viscoelastic properties are regulated in different manners according to various task requirements. The viscoelasticity consists of joint stiffness and viscosity. The research of the viscoelasticity can improve the development of industrial robots, rehabilitation and sports etc. So far, some results have been shown using filtered human arm viscoelasticity measurements. That is, human motor command is removed. As a result, the dynamics of human voluntary component during movements is omitted. In this paper, based on the feedforward characteristics of human multi joint arm, a model is obtained by considering human voluntary components using a support vector regression technique. By employing the learned model, a nonlinear intelligent control of two link robot arm is proposed. Experimental results confirm the effectiveness of this proposal.