bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling of the Peptide Release during Proteolysis of β-Lactoglobulin by Trypsin with Consideration of Peptide Bond Demasking
Authors: Vorob’ev Mikhail M.
Published: July 2023

Prospects for predicting the fragmentation of polypeptide chains during their enzymatic hydrolysis using proteolysis models are considered. The opening of the protein substrate during proteolysis and the exposure of its internal peptide bonds for a successful enzymatic attack, the so-called demasking process, were taken into account. The two-step proteolysis model was used, including the parameters of demasking and the rate constants of hydrolysis of enzyme-specific peptide bonds. Herein, we have presented an algorithm for calculating the concentrations of intermediate and final peptide fragments depending on the time of hydrolysis or the degree of hydrolysis. The intermediate peptide fragments with two or one internal specific peptide bond were considered. The fragmentation of β-lactoglobulin (β-LG) by trypsin was predicted, and the calculated concentration curves for peptide fragments were compared with the experimental dependences of the concentrations on the degree of hydrolysis. Numerical parameters were proposed that characterize the concentration curves for intermediate and final peptide fragments, and they were used to compare the calculated and experimental dependences. The predicted distribution of the peptide fragments corresponded to the experimental data on the peptide release during the proteolysis of β-LG by trypsin.
Efficient Non-Sampling Graph Neural Networks
Authors: Ji Jianchao , Li Zelong , Xu Shuyuan , Ge Yingqiang , Tan Juntao , Zhang Yongfeng
Published: July 2023

A graph is a widely used and effective data structure in many applications; it describes the relationships among nodes or entities. Currently, most semi-supervised or unsupervised graph neural network models are trained based on a very basic operation called negative sampling. Usually, the purpose of the learning objective is to maximize the similarity between neighboring nodes while minimizing the similarity between nodes that are not close to each other. Negative sampling can reduce the time complexity by sampling a small fraction of the negative nodes instead of using all of the negative nodes when optimizing the objective. However, sampling of the negative nodes may fail to deliver stable model performance due to the uncertainty in the sampling procedure. To avoid such disadvantages, we provide an efficient Non-Sampling Graph Neural Network (NS-GNN) framework. The main idea is to use all the negative samples when optimizing the learning objective to avoid the sampling process. Of course, directly using all of the negative samples may cause a large increase in the model training time. To mitigate this problem, we rearrange the origin loss function into a linear form and take advantage of meticulous mathematical derivation to reduce the complexity of the loss function. Experiments on benchmark datasets show that our framework can provide better efficiency at the same level of prediction accuracy compared with existing negative sampling-based models.
Conditioned Media from Human Pulp Stem Cell Cultures Improve Bone Regeneration in Rat Calvarial Critical-Size Defects
Authors: Buss Leonardo Fernandes , de Martin Gustavo Sigrist , Martinez Elizabeth Ferreira , Filgueiras Isabela Amanda de Abreu Araújo Porcaro , Magnabosco José Luiz , Alves Bruno Frenhan , de Macedo Almeida Bruno , Kotaka Tatiana , Teixeira Marcelo Lucchesi , Ferreira José Ricardo Muniz , Rocha Daniel Navarro da , Canal Raul , Aloise Antonio Carlos , Holliday Lexie Shannon , Pelegrine André Antonio
Published: July 2023

The aim of this study was to test whether lyophilized conditioned media from human dental pulp mesenchymal stem cell cultures promote the healing of critical-size defects created in the calvaria of rats. Prior to the surgical procedure, the medium in which dental pulp stem cells were cultured was frozen and lyophilized. After general anesthesia, an 8 mm diameter bone defect was created in the calvaria of twenty-four rats. The defects were filled with the following materials: xenograft alone (G1) or xenograft associated with lyophilized conditioned medium (G2). After 14 or 42 days, the animals were euthanized, and the specimens processed for histologic and immunohistochemical analysis. Bone formation at the center of the defect was observed only in the G2 at 42 days. At both timepoints, increased staining for VEGF, a marker for angiogenesis, was observed in G2. Consistent with this, at 14 days, G2 also had a higher number of blood vessels detected by immunostaining with an anti-CD34 antibody. In conclusion, conditioned media from human dental pulp mesenchymal stem cell cultures had a positive effect on the regenerative process in rat critical-size bone defects. Both the formation of bone and enhancement of vascularization were stimulated by the conditioned media.
Review of Orthogonal Frequency Division Multiplexing-Based Modulation Techniques for Light Fidelity
Authors: Alindra Rahmayati , Priambodo Purnomo Sidi , Ramli Kalamullah
Published: July 2023

Light Fidelity (LiFi) technology has gained attention and is growing rapidly today. Utilizing light as a propagation medium allows LiFi to promise a wider bandwidth than existing Wireless Fidelity (WiFi) technology and enables the implementation of cellular technology to improve bandwidth utilization. In addition, LiFi is very attractive because it can utilize lighting facilities consisting of light-emitting diodes (LEDs). A LiFi system that uses intensity modulation and direct detection requires the signal of orthogonal frequency division multiplexing (OFDM) to have a real and non-negative value; therefore, certain adjustments must be made. The proposed methods for generating unipolar signals vary from adding a direct current, clipping the signal, superposing several unipolar signals, and hybrid methods as in DC-biased optical (DCO)-OFDM, asymmetrically clipped optical (ACO)-OFDM, layered ACO (LACO)-OFDM, and asymmetrically clipped DC-biased optical (ADO)-OFDM, respectively. In this paper, we review and compare various modulation techniques to support the implementation of LiFi systems using commercial LEDs. The main objective is to obtain a modulation technique with good energy efficiency, efficient spectrum utilization, and low computational complexity so that it is easy for us to apply it in experiments on a laboratory scale.
A Spiral-Propulsion Amphibious Intelligent Robot for Land Garbage Cleaning and Sea Garbage Cleaning
Authors: Zhang Yanghai , Huang Zan , Chen Changlin , Wu Xiangyu , Xie Shuhang , Zhou Huizhan , Gou Yihui , Gu Liuxin , Ma Mengchao
Published: July 2023

To address the issue of current garbage cleanup vessels being limited to performing garbage cleaning operations in the ocean, without the capability of transferring the garbage from the ocean to the land, this paper presents a spiral-propulsion amphibious intelligent robot for land garbage cleaning and sea garbage cleaning. The design solution is as follows. A mechanical structure based on a spiral drum is proposed. The interior of the spiral drum is hollow, providing buoyancy, allowing the robot to travel both on marshy, tidal flats and on the water surface, in conjunction with underwater thrusters. Additionally, a mechanical-arm shovel is designed, which achieves two-degrees-of-freedom movement through a spiral spline guide and servo, facilitating garbage collection. Our experimental results demonstrated that the robot exhibits excellent maneuverability in marine environments and on beach, marsh, and tidal flat areas, and that it collects garbage effectively.
Cytochrome P450 Gene Families: Role in Plant Secondary Metabolites Production and Plant Defense
Authors: Chakraborty Panchali , Biswas Ashok , Dey Susmita , Bhattacharjee Tuli , Chakrabarty Swapan
Published: July 2023

Cytochrome P450s (CYPs) are the most prominent family of enzymes involved in NADPH- and O2-dependent hydroxylation processes throughout all spheres of life. CYPs are crucial for the detoxification of xenobiotics in plants, insects, and other organisms. In addition to performing this function, CYPs serve as flexible catalysts and are essential for producing secondary metabolites, antioxidants, and phytohormones in higher plants. Numerous biotic and abiotic stresses frequently affect the growth and development of plants. They cause a dramatic decrease in crop yield and a deterioration in crop quality. Plants protect themselves against these stresses through different mechanisms, which are accomplished by the active participation of CYPs in several biosynthetic and detoxifying pathways. There are immense potentialities for using CYPs as a candidate for developing agricultural crop species resistant to biotic and abiotic stressors. This review provides an overview of the plant CYP families and their functions to plant secondary metabolite production and defense against different biotic and abiotic stresses.
A Cultural Landscape Emerges: Analyzing the Evolution of Two Historic North Pole Expedition Bases in Virgohamna, Svalbard, from Trash to a Protected Cultural Heritage Site
Authors: Flyen Anne Cathrine
Published: July 2023

The identification and preservation of cultural landscapes worthy of protection is a challenging task, as their significance is often not immediately apparent. Analyzing the process through which a site or landscape became a heritage site and understanding the historical context and the factors that contributed to its designation allows making informed decisions on the management and preservation of the site. To provide research-based knowledge, this paper aims to analyze the transformation of the degraded remains of the North Pole expedition bases of Andrée and Wellman in Virgohamna, Svalbard, into a protected historic landscape and the subsequent emergence of the site as a current popular tourist destination. Virgohamna serves as an illustrative case for examining the heritagization process of cultural heritage sites in Svalbard. This article adopts a multidisciplinary approach, drawing upon case studies, mapping and categorizing the historic and current landscape, the condition and vulnerability assessment of historic remains, behavior studies on visiting tourists and guides on-site, expert interviews, and document studies. The findings highlight the complex processes that have influenced the making of the cultural heritage landscape in Virgohamna, the enduring narrative associated with the site, and the need for continued efforts to ensure the preservation and dissemination of its historical significance. Analyzing the process through which Virgohamna has become a heritage site and understanding the historical context and the factors that have contributed to its designation as a heritage site has the potential to enhance comprehension regarding historical importance and heritage values. Furthermore, it might facilitate engaging stakeholders and formulating management approaches and provide insights for policy suggestions. The comprehensive examination serves as a foundation for responsible and sustainable heritage management, ensuring the preservation and promotion of Virgohamna’s cultural heritage for present and future generations.
Key Technologies and Design Methods of Ultra-Precision Aerostatic Bearings
Authors: Wen Zhongpu , Gu Hui , Shi Zhaoyao
Published: July 2023

Precision measurement technology and instruments are the basis for high-quality development in modern industry. With the specialization of supporting facilities, ultra-precision motion guidance has become a core technology to achieve ultra-precision measurement. Aerostatic bearings have the advantages of low friction and high precision, and are gradually playing an irreplaceable role in precision measurement and instruments. This paper summarizes and puts forward two contradictions for improving the loading capacity of aerostatic bearings, and investigates how to solve them via structural design. This paper analyzes the characteristics of the engineering calculation method, the gauge pressure ratio method, the gas resistance calculation method, and the AFVM (adaptive finite volume method) proposed. Finally, this paper summarizes the application scope of each method, gives solutions to the core problems, and outlines the developing trends.
Additive Manufacturing of Cu Using Graphene-Oxide-Treated Powder
Authors: Tidén Simon , Taher Mamoun , Vennström Marie , Jansson Ulf
Published: July 2023

Additive manufacturing of Cu is interesting for many applications where high thermal and electric conductivity are required. A problem with printing of Cu with a laser-based process is the high reflectance of the powder for near-infrared wavelengths making it difficult to print components with a high density. In this study, we have investigated laser bed fusion (L-PBF) of Cu using graphene oxide (GO)-coated powder. The powder particles were coated in a simple wet-chemical process using electrostatic attractions between the GO and the powder surface. The coated powder exhibited a reduced reflectivity, which improved the printability and increased the densities from ~90% for uncoated powder to 99.8% using 0.1 wt% GO and a laser power of 500 W. The coated Cu powders showed a tendency for balling using laser powers below 400 W, and increasing the GO concentration from 0.1 to 0.3 wt.% showed an increase in spattering and reduced density. Graphene-like sheet structures could be observed in the printed parts using scanning electron microscopy (SEM). Carbon-filled inclusions with sizes ranging from 10–200 nm could also be observed in the printed parts using transmission electron microscopy (TEM). The GO treatment yielded parts with higher hardness (75.7 HV) and electrical conductivity (77.8% IACS) compared to the parts printed with reference Cu powder.
Preface to the Special Issue “Algebraic Structures and Graph Theory”
Authors: Cristea Irina , Bordbar Hashem
Published: July 2023

Connections between algebraic structure theory and graph theory have been established in order to solve open problems in one theory with the help of the tools existing in the other, emphasizing the remarkable properties of one theory with techniques involving the second [...]
Supply Chain Scheduling Method for the Coordination of Agile Production and Port Delivery Operation
Authors: Yu Xiaoyu , Qian Jingyi , Zhang Yajing , Kong Min
Published: July 2023

The cost-reducing potential of intelligent supply chains (ISCs) has been recognized by companies and researchers. This paper investigates a two-echelon steel supply chain scheduling problem that considers the parallel-batching processing and deterioration effect in the production stage and sufficient vehicles in the port delivery stage. To solve this problem, we first analyze several sufficient and necessary conditions of the optimal scheme. We then propose a heuristic algorithm based on a dynamic programming algorithm to obtain the optimal solution for a special case where the assignment of all ingots to the soaking pits is known. Based on the results of this special case, we develop a modified biased random-key genetic algorithm (BRKGA), which incorporates genetic operations based on the flower pollination algorithm (FPA) to obtain joint production and distribution schedules for the general problem. Finally, we conduct a series of computational experiments, the results of which indicate that BRKGA-FPA has certain advantages in solving quality and convergence speed issues.
Research Status and Prospective Properties of the Al-Zn-Mg-Cu Series Aluminum Alloys
Authors: Wang Jue , Li Faguo
Published: July 2023

An Al–Zn–Mg–Cu alloy has high specific strength, good corrosion resistance, fracture toughness and fatigue resistance. It is one of the most important structural materials in the fields of aviation, aerospace, weapons and transportation; in particular, it plays a huge role in the field of aerospace. In order to optimize the strength, toughness and corrosion properties of an Al–Zn–Mg–Cu alloy, the focus of research on this alloy has always been on the alloying process. The effects of the main alloying elements, trace alloying elements and rare earth elements on the microstructure and properties of Al–Zn–Mg–Cu alloys are briefly introduced in this paper, and future research directions are proposed.
Biosynthetic Pathways of Hormones in Plants
Authors: Bajguz Andrzej , Piotrowska-Niczyporuk Alicja
Published: July 2023

Phytohormones exhibit a wide range of chemical structures, though they primarily originate from three key metabolic precursors: amino acids, isoprenoids, and lipids. Specific amino acids, such as tryptophan, methionine, phenylalanine, and arginine, contribute to the production of various phytohormones, including auxins, melatonin, ethylene, salicylic acid, and polyamines. Isoprenoids are the foundation of five phytohormone categories: cytokinins, brassinosteroids, gibberellins, abscisic acid, and strigolactones. Furthermore, lipids, i.e., α-linolenic acid, function as a precursor for jasmonic acid. The biosynthesis routes of these different plant hormones are intricately complex. Understanding of these processes can greatly enhance our knowledge of how these hormones regulate plant growth, development, and physiology. This review focuses on detailing the biosynthetic pathways of phytohormones.
A Compact Fully Electronically Tunable Memristive Circuit Based on CCCDTA with Experimental Results
Authors: Ozenli Deniz
Published: July 2023

This work presents a flux-controlled memristor structure employing a Current-Controlled Current Differencing Transconductance Amplifier (CCCDTA) with a grounded capacitor. The proposed emulator’s invariant and variant parts can be safely adjustable, showing promising characteristics of up to 1.5 MHz operating frequency. Furthermore, there is no need for an additional circuit, switching mechanism or changing the circuit topology for the changing of operation modes. To justify the performance of the emulator with incremental and decremental mode operations, a Monte Carlo and temperature analysis are validated using TSMC 0.18 µm technology under a symmetrical supply voltage of ±0.9 V. Furthermore, the workability of the proposed circuit is tested with commercial elements such as ALD1116, AD844 and LM13700. When compared with other studies, the presented emulator circuit demonstrates promising performance in various features.
Mode Characterization and Sensitivity Evaluation of a Surface Acoustic Wave (SAW) Resonator Biosensor: Application to the Glial-Fibrillary-Acidic-Protein (GFAP) Biomarker Detection
Authors: Passeri Antonio Matteo , Lunardelli Francesco , Cavariani Daniele , Cecchini Marco , Agostini Matteo
Published: July 2023

Biosensors based on surface acoustic waves (SAWs) offer unique advantages due to their high sensitivity, real-time response capability, and label-free detection. The typical SAW modes are the Rayleigh mode and the shear-horizontal mode. Both present pros and cons for biosensing applications and generally need different substrates and device geometries to be efficiently generated. This study investigates and characterizes SAW resonator biosensors on lithium niobate in terms of modes generated and biosensing performance. It reveals the simultaneous presence of two typical SAW modes, the first around 1.6 GHz and the second around 1.9 GHz, differently polarized and clearly separated in frequency, which we refer to as slow and fast modes. The two modes are studied by numerical simulations and biosensing experiments with the glial-fibrillary-acidic-protein (GFAP) biomarker. The slow mode is generally more sensitive to changes in surface properties, such as temperature and mass changes, by a factor of about 1.4 with respect to the fast mode.
Experimental Investigations upon Ultrasound Influence on Calefaction of AdBlue in Selective Catalytic Reduction Systems (SCR)
Authors: Picus Claudiu Marian , Mihai Ioan , Suciu Cornel
Published: July 2023

The present paper intends to provide an analysis of how the process of calefaction occurs in a selective catalytic reduction (SCR) system and the mechanisms by which the deposition of AdBlue crystals on a hot surface evolve. Experimentally, two aluminium samples heated to 200 °C were used, over which AdBlue droplets with different atomisation rates were dropped, maintaining the same dynamic flow parameters, in order to observe the influence of temperature effects on the degree of deposition of crystallised sediment on the surface. The authors proposed the use of calefaction in an ultrasonic environment to prevent deposition and to increase droplet fragmentation by a break-up process. To prove the performance of this method one sample was subjected to a normal flow regime while a second sample was exposed to ultrasound. Both samples were assembled on a magneto-strictive concentrator operating at a frequency of 20 kHz. The obtained results indicated that the sample exposed to ultrasound demonstrated lower urea crystallisation compared to the sample that was not exposed to this treatment. Thus, it can be seen that the proposed method of injecting AdBlue into an ultrasonic zone gives the desired results.
A Highly Sensitive and High-Resolution Resonant MEMS Electrostatic Field Microsensor Based on Electrostatic Stiffness Perturbation
Authors: Liu Xiangming , Xia Shanhong , Peng Chunrong , Gao Yahao , Peng Simin , Zhang Zhouwei , Zhang Wei , Xing Xuebin , Liu Yufei
Published: July 2023

This paper proposes a highly sensitive and high-resolution resonant MEMS electrostatic field sensor based on electrostatic stiffness perturbation, which uses resonant frequency as an output signal to eliminate the feedthrough interference from the driving voltage. The sensor is composed of a resonator, driving electrode, detection electrode, transition electrode, and electrostatic field sensing plate. The working principle is that when there is an electrostatic field, an induction charge will appear at the surface of the electrostatic field sensing plate and induce electrostatic stiffness on the resonator, which will cause a resonant frequency shift. The resonant frequency is used as the output signal of the microsensor. The characteristics of the electrostatic field sensor are analyzed with a theoretical model and verified by finite element simulation. A device prototype is fabricated based on the Silicon on Insulator (SOI) process and tested under vacuum conditions. The results indicate that the sensitivity of the sensor is 0.1384Hz/(kV/m) and the resolution is better than 10 V/m.
Ultraviolet-C-Based Mobile Phone Sanitisation for Global Public Health and Infection Control
Authors: Olsen Matthew , Goldsworthy Adrian , Nassar Rania , Senok Abiola , Albastaki Abdullah , Lee Zheng Z. , Abraham Sam , Alghafri Rashed , Tajouri Lotti , McKirdy Simon
Published: July 2023

Introduction. Mobile phones act as fomites that pose a global public health risk of disseminating microorganisms, including highly pathogenic strains possessing antimicrobial resistances. The use of ultraviolet-C (UV-C) to sanitise mobile phones presents an alternative means to complement basic hand hygiene to prevent the cross-contamination and dissemination of microorganisms between hands and mobile phones. Aim. This study aimed to evaluate the germicidal efficacy of the Glissner CleanPhone UV-C phone sanitiser (Glissner) device. Methods. Two experimental trials were performed for the evaluation of the CleanPhone (Glissner). The first was a controlled trial, where the germicidal efficacy of the CleanPhone was evaluated against six different microorganism species that were inoculated onto mobile phones. The second was a field trial evaluating the germicidal efficacy of the CleanPhone on 100 volunteer mobile phones. Efficacy was determined based on colony counts of microorganisms on Columbia sheep blood agar before and after UV-C treatment. Results. In the controlled trial, reduction in growth was observed for all microorganisms after UV-C treatment with ST131 Escherichia coli showing the highest growth reduction at 4 log10 CFU/mL followed by C. albicans and ATCC E. coli at 3 log10 CFU/mL. An overall reduction in microorganism growth after UV-C treatment was also observed for the field trial, with an average growth reduction of 84.4% and 93.6% in colony counts at 24 h and 48 h post-incubation, respectively. Conclusion. The findings demonstrated the capability of the CleanPhone (Glissner) to rapidly sanitise mobile phones, thereby providing a means to reduce the potential dissemination of microorganisms, including highly pathogenic strains with antimicrobial resistance.
Whole-Genome Sequencing of Mycobacterium tuberculosis Isolates from Diabetic and Non-Diabetic Patients with Pulmonary Tuberculosis
Authors: Shankaregowda Ranjitha , Allegretti Yuan Hu , Sumana Mahadevaiah Neelambike , Rao Morubagal Raghavendra , Raphael Eva , Mahesh Padukudru Anand , Riley Lee W.
Published: July 2023

The association of tuberculosis and type 2 diabetes mellitus has been a recognized re-emerging challenge in management of the convergence of the two epidemics. Though much of the literature has studied this association, there is less knowledge in the field of genetic diversities that might occur in strains infecting tuberculosis patients with and without diabetes. Our study focused on determining the extent of diversity of genotypes of Mycobacterium tuberculosis in both these categories of patients. We subjected 55 M. tuberculosis isolates from patients diagnosed with pulmonary TB with and without type 2 diabetes mellitus to whole-genome sequencing on Illumina Hi Seq platform. The most common lineage identified was lineage 1, the Indo-Oceanic lineage (n = 22%), followed by lineage 4, the Euro-American lineage (n = 18, 33%); lineage 3, the East-African Indian lineage (n = 13, 24%); and lineage 2, the East-Asian lineage (n = 1, 2%). There were no significant differences in the distribution of lineages in both diabetics and non-diabetics in the South Indian population, and further studies involving computational analysis and comparative transcriptomics are needed to provide deeper insights.
Lumpy Skin Disease Virus Infection Activates Autophagy and Endoplasmic Reticulum Stress-Related Cell Apoptosis in Primary Bovine Embryonic Fibroblast Cells
Authors: Tan Jinlong , Liu Yinju , Li Weike , Zhang Yongzhi , Chen Guohua , Fang Yongxiang , He Xiaobing , Jing Zhizhong
Published: July 2023

Poxviruses have been associated with humans for centuries. From smallpox to mpox to lumpy skin disease virus (LSDV), members of the poxvirus family have continued to threaten the lives of humans and domestic animals. A complete understanding of poxvirus-mediated cellular processes will aid in the response to challenges from the viruses. In this study, we demonstrate that LSDV infection results in an abnormal ultrastructure of the endoplasmic reticulum (ER) lumen in primary bovine embryonic fibroblast (BEF) cells, and we further show that an ER imbalance occurs in LSDV-infected BEF cells. Additionally, we believe that ER stress-related apoptosis plays a role in the late apoptosis of BEF cells infected with LSDV, primarily through the activation of the CCAAT/enhancer binding protein homologous protein (CHOP)-Caspase-12 signal. In addition to cell apoptosis, a further investigation showed that LSDV could also activate autophagy in BEF cells, providing additional insight into the exact causes of LSDV-induced BEF cell death. Our findings suggest that LSDV-induced BEF cell apoptosis and autophagy may provide new avenues for laboratory diagnosis of lumpy skin disease progression and exploration of BEF cell processes.
Simulation and Observations of Audio Magnetotelluric Measurements over Water-Covered Areas
Authors: Wu Qiong , Li Yong-Bo , Mi Hong-Ze , Wang Gang , Zhang Zhen-Yu
Published: July 2023

Electromagnetic (EM) surveys play a significant role in mineral exploration. However, the EM method often faces limitations when investigating minerals in areas covered by rivers, lakes, or other water bodies. This paper introduces audio magnetotelluric (AMT) observation technology that utilizes separated electric and magnetic channels to deal with this challenge over water-covered areas. The study analyzes and discusses the characteristics of the relative error of the magnetic field through forward simulation. The observation and profile experiments were conducted at the estuary of a river in Liaoning Province, China, and high-quality data in the river and the pseudo-geoelectric section of the underwater space were successfully obtained. The results demonstrate the feasibility and effectiveness of the AMT observation technology over water-covered areas, emphasizing the importance of locating the magnetic channel in a quiet zone at a certain distance from the shore. This configuration helps reduce the influence of resistivity differences between water and shore, ultimately improving data quality and accuracy. The research suggests that the AMT observation technology, utilizing separated electric and magnetic channels, has the potential for further improvement and can serve as a valuable guide for mineral exploration over water-covered areas.
Apitherapy in Post-Ischemic Brain Neurodegeneration of Alzheimer’s Disease Proteinopathy: Focus on Honey and Its Flavonoids and Phenolic Acids
Authors: Pluta Ryszard , Miziak Barbara , Czuczwar Stanisław J.
Published: July 2023

Neurodegeneration of the brain after ischemia is a major cause of severe, long-term disability, dementia, and mortality, which is a global problem. These phenomena are attributed to excitotoxicity, changes in the blood–brain barrier, neuroinflammation, oxidative stress, vasoconstriction, cerebral amyloid angiopathy, amyloid plaques, neurofibrillary tangles, and ultimately neuronal death. In addition, genetic factors such as post-ischemic changes in genetic programming in the expression of amyloid protein precursor, β-secretase, presenilin-1 and -2, and tau protein play an important role in the irreversible progression of post-ischemic neurodegeneration. Since current treatment is aimed at preventing symptoms such as dementia and disability, the search for causative therapy that would be helpful in preventing and treating post-ischemic neurodegeneration of Alzheimer’s disease proteinopathy is ongoing. Numerous studies have shown that the high contents of flavonoids and phenolic acids in honey have antioxidant, anti-inflammatory, anti-apoptotic, anti-amyloid, anti-tau protein, anticholinesterase, serotonergic, and AMPAK activities, influencing signal transmission and neuroprotective effects. Notably, in many preclinical studies, flavonoids and phenolic acids, the main components of honey, were also effective when administered after ischemia, suggesting their possible use in promoting recovery in stroke patients. This review provides new insight into honey’s potential to prevent brain ischemia as well as to ameliorate damage in advanced post-ischemic brain neurodegeneration.
Theoretical and Experimental Studies on the Evidence of 1,3-β-Glucan in Marennine of Haslea ostrearia
Authors: Yusuf Muhammad , Baroroh Umi , Nuwarda Rina Fajri , Prasetiya Fiddy Semba , Ishmayana Safri , Novianti Mia Tria , Tohari Taufik Ramdani , Hardianto Ari , Subroto Toto , Mouget Jean-Luc , Pasetto Pamela
Published: July 2023

Marennine, a blue pigment produced by the blue diatom Haslea ostrearia, is known to have some biological activities. This pigment is responsible for the greening of oysters on the West Coast of France. Other new species of blue diatom, H. karadagensis, H. silbo sp. inedit., H. provincialis sp. inedit, and H. nusantara, also produce marennine-like pigments with similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms present a commercial potential for the aquaculture, food, cosmetics, and health industries. Unfortunately, for a hundred years, the exact molecular structure of this bioactive compound has remained a mystery. A lot of hypotheses regarding the chemical structure of marennine have been proposed. The recent discovery of this structure revealed that it is a macromolecule, mainly carbohydrates, with a complex composition. In this study, some glycoside hydrolases were used to digest marennine, and the products were further analyzed using nuclear magnetic resonance (NMR) and mass spectroscopy (MS). The reducing sugar assay showed that marennine was hydrolyzed only by endo-1,3-β-glucanase. Further insight into the structure of marennine was provided by the spectrum of 1H NMR, MS, a colorimetric assay, and a computational study, which suggest that the chemical structure of marennine contains 1,3-β-glucan.
Iodine Biofortification of Dandelion Plants (Taraxacum officinale F.H. Wiggers Coll.) with the Use of Inorganic and Organic Iodine Compounds
Authors: Ledwożyw-Smoleń Iwona , Pitala Joanna , Smoleń Sylwester , Liszka-Skoczylas Marta , Kováčik Peter
Published: July 2023

Iodine is a crucial microelement necessary for the proper functioning of human and animal organisms. Plant biofortification has been proposed as a method of improving the iodine status of the population. Recent studies in that field have revealed that iodine may also act as a beneficial element for higher plants. The aim of the work was to evaluate the efficiency of the uptake and accumulation of iodine in the plants of dandelion grown in a pot experiment. During cultivation, iodine was applied through fertigation in inorganic (KI, KIO3) and organic forms (5-iodosalicylic acid, 5-ISA; 3,5-diiodosalicylic acid, 3,5-diISA) at two concentrations (10 and 50 µM). The contents of total iodine and iodosalicylic acids, as well the plant biomass and antioxidant capacity of dandelion leaves and roots, were analyzed. The uptake of inorganic and organic forms by dandelion plants was confirmed with no negative effect on plant growth. The highest efficiency of improving iodine content in dandelion leaves and roots was noted for 50 µM KI. The applicability of iodosalicylates, especially 5-ISA, for plant biofortification purposes was confirmed, particularly as the increase in the iodine content after the application of 5-ISA was higher as compared to that with commonly used KIO3. The chemical analyses have revealed that iodosalicylates are endogenous compounds of dandelion plants.
Structures, Electronic, and Magnetic Properties of CoKn (n = 2–12) Clusters: A Particle Swarm Optimization Prediction Jointed with First-Principles Investigation
Authors: Jiang Yi , Aireti Maidina , Leng Xudong , Ji Xu , Liu Jing , Cui Xiuhua , Duan Haiming , Jing Qun , Cao Haibin
Published: July 2023

Transition-metal-doped clusters have long been attracting great attention due to their unique geometries and interesting physical and/or chemical properties. In this paper, the geometries of the lowest- and lower-energy CoKn (n = 2–12) clusters have been screened out using particle swarm optimization and first principles relaxation. The results show that except for CoK2 the other CoKn (n = 3–12) clusters are all three-dimensional structures, and CoK7 is the transition structure from which the lowest energy structures are cobalt atom-centered cage-like structures. The stability, the electronic structures, and the magnetic properties of CoKn clusters (n = 2–12) clusters are further investigated using the first principles method. The results show that the medium-sized clusters whose geometries are cage-like structures are more stable than smaller-sized clusters. The electronic configuration of CoKn clusters could be described as 1S1P1D according to the spherical jellium model. The main components of petal-shaped D molecular orbitals are Co-d and K-s states or Co-d and Co-s states, and the main components of sphere-like S molecular orbitals or spindle-like P molecular orbitals are K-s states or Co-s states. Co atoms give the main contribution to the total magnetic moments, and K atoms can either enhance or attenuate the total magnetic moments. CoKn (n = 5–8) clusters have relatively large magnetic moments, which has a relation to the strong Co-K bond and the large amount of charge transfer. CoK4 could be a magnetic superatom with a large magnetic moment of 5 μB.
Preparation of SiO2@Au Nanoparticle Photonic Crystal Array as Surface-Enhanced Raman Scattering (SERS) Substrate
Authors: Song Dingyu , Wang Tianxing , Zhuang Lin
Published: July 2023

Surface-enhanced Raman scattering technology plays a prominent role in spectroscopy. By introducing plasmonic metals and photonic crystals as a substrate, SERS signals can achieve further enhancement. However, the conventional doping preparation methods of these SERS substrates are insufficient in terms of metal-loading capacity and the coupling strength between plasmonic metals and photonic crystals, both of which reduce the SERS activity and reproducibility of SERS substrates. In this work, we report an approach combining spin-coating, surface modification, and in situ reduction methods. Using this approach, a photonic crystal array of SiO2@Au core–shell structure nanoparticles was prepared as a SERS substrate (SiO2@Au NP array). To study the SERS properties of these substrates, Rhodamine 6G was employed as the probe molecule. Compared with a Au-SiO2 NP array prepared using doping methods, the SiO2@Au NP array presented better SERS properties, and it reproduced the SERS spectra after one month. The detection limit of the Rhodamine 6G on SiO2@Au NP array reached 1 × 10−8 mol/L; furthermore, the relative standard deviation (9.82%) of reproducibility and the enhancement factor (1.51 × 106) were evaluated. Our approach provides a new potential option for the preparation of SERS substrates and offers a potential advantage in trace contaminant detection, and nondestructive testing.
A Thermal, Mechanical, and Materials Framework for a Shape Memory Alloy Heat Engine for Thermal Management
Authors: Chikhareva Maria , Vaidyanathan Raj
Published: July 2023

Shape memory alloy (SMA) heat engines possess an inherent property of sensing a change in temperature, performing work, and rejecting heat through the shape memory effect resulting from a temperature-induced phase transformation. This work presents a framework for the design and implementation of an SMA-based Stirling heat engine for maximum torque or speed incorporating and combining mechanical, thermal, and material aspects. There is a growing need for such engines for reliable thermal management and energy recovery in both ground and space applications. Mechanical aspects were addressed from force balances in the SMA element and focused on the resulting stress distribution. Thermal aspects considered heat transfer between the SMA element and both the heat source and the heat sink. Materials aspects considered the chemical, elastic, and frictional contributions to the enthalpy of the transformation. The roles of nano- and microstructure through composition, precipitates, variant interfaces, training, cycling, texture, defects, nucleation sites (bulk vs. surface), and multi-step transformations (e.g., a trigonal R-phase transformation) in NiTi based-alloys are also emphasized. The aforementioned aspects were combined to present a figure of merit to aid in the design and implementation of a Nitinol Stirling heat engine operating to maximize torque or maximize speed.
Phytochemical Profiling, Antioxidant and Cognitive-Enhancing Effect of Helichrysum italicum ssp. italicum (Roth) G. Don (Asteraceae)
Authors: Gevrenova Reneta , Kostadinova Ivanka , Stefanova Alexandra , Balabanova Vessela , Zengin Gokhan , Zheleva-Dimitrova Dimitrina , Momekov Georgi
Published: July 2023

This study aimed at the evaluation of the antioxidant and cognitive-enhancing effect of methanol–aqueous extract from Helichrysum italicum ssp. italicum aerial parts. Significant radical scavenging activity (110.33 ± 3.47 and 234.70 ± 5.21 mg TE/g for DPPH and ABTS) and reducing power (354.23 ± 17.51 and 210.24 ± 8.68 mg TE/g for CUPRAC and FRAP) were observed. The extract showed average acetylcholinesterase and low butyrylcholinesterase inhibitory potential. H. italicum extract (200 mg/kg/po) administered in combination with galantamine (3 mg/kg/po) for 12 days significantly improved the memory and learning process compared with galantamine alone in the passive avoidance test. The effect was comparable to that of Ginkgo biloba extract (100 mg/kg/po). In deep secondary metabolite annotation of the extract by UHPLC-HRMS, more than 90 hydroxybenzoic and hydroxicinnamic acid-glycosides, phenylethanoid glycosides, a series of acylquinic and caffeoylhexaric acids, methoxylated derivatives of scutellarein, quercetagetin and 6-hydroxyluteolin, and prenylated phloroglucinol-α-pyrones were reported for the first time in H. italicum. Fragmentation patterns of four subclasses of heterodimer-pyrones were proposed. In-depth profiling of the pyrones revealed 23 compounds undescribed in the literature. Pyrones and acylphloroglucinols together with acylquinic acids could account for memory improvement. The presented research advanced our knowledge of H. italicum, highlighting the species as a rich source of secondary metabolites with cognitive-enhancing potential.
Comparative Analysis of Growth and Physiological Responses of Sugarcane Elite Genotypes to Water Stress and Sandy Loam Soils
Authors: Sajid Muhammad , Amjid Muhammad , Munir Hassan , Ahmad Muhammad , Zulfiqar Usman , Ali Muhammad Fraz , Abul Farah Mohammad , Ahmed Mohamed A. A. , Artyszak Arkadiusz
Published: July 2023

Stumpy irrigation water availability is extremely important for sugarcane production in Pakistan today. This issue is rising inversely to river flow due to inadequate water distribution and an uneven rainfall pattern. Sugarcane growth faces a shortage of available water for plant uptake due to the low water–holding capacity of sandy loam soil, particularly under conventional flood irrigation methods. To address this problem, sugarcane clones were evaluated for their agronomic and physiological traits under conditions of low water availability in sandy loam soil. Ten cane genotypes, HSF–240, SPF–213, CPF–249, CP 77–400, S2008–FD–19, S2006–US–469, S2007–AUS–384, S2003–US–633, S2003–US–127, and S2006–US–658, were exposed to four levels of water deficit created through skip irrigations. These deficit levels occurred during the 9th, 11th, 13th, and 16th irrigations at alternate deficit levels between 2020 and 2022. Physiological data were collected during the tillering and grand growth stages (elongation) in response to the water deficit. The sugarcane clones S2006–US–658, S2007–AUS–384, and HSF–240 exhibited resistance to low water availability at both the tillering and grand growth stages. Following them, genotypes S2006–US–658, S2007–AUS–384, and HSF–240 performed better and were also found to be statistically significant. Clones susceptible to water deficit in terms of growth and development were identified as CP 77–400, S2008–FD–19, S2006–US–469, and S2003–US–633. These genotypes showed reduced photosynthetic rate, transpiration rate, stomatal conductance, relative water content, cane yield, and proline content under stressed conditions. Therefore, genotypes S2006–US–658, S2007–AUS–384, and HSF–240 were better performers concerning physiological traits under water deficit and sandy loam soil in both years. Moreover, a significant positive correlation was assessed between agronomic traits and photosynthetic rats. This study highlights that sugarcane can sustain its growth and development even with less irrigation frequency or moisture availability, albeit with certain specific variations.
Application of Essential Oils Extracted from Peel Wastes of Four Orange Varieties to Control Anthracnose Caused by Colletotrichum scovillei and Colletotrichum gloeosporioides on Mangoes
Authors: Duong Chau Trung , Thao Huynh Thi Phuong , Y Nguyen Thi Nhu , Tien Doan Thi Kieu , Nga Nguyen Thi Thu , Nhan Tran Chi , Huong Bui Thi Cam , Ercisli Sezai , Truc Nguyen Thi Ngoc , Danh Luu Thai
Published: July 2023

A huge amount of orange peel waste is annually discharged into the environment. Processing of this waste for the control of post-harvest fruit diseases can reduce environmental pollution. Essential oils (EOs) from fruit peels of Citrus reticulata × sinensis (Sanh cultivar) and Citrus sinensis (Xoan, Mat and Navel cultivar) were investigated for their ability to control anthracnose caused by Colletotrichum gloeosporioides and Colletotrichum scovillei on mangoes. EOs were extracted by hydro-distillation and analyzed by GC-MS and GC-FID. The antifungal activity of the EOs was determined by in vitro and in vivo assays. The Mat cultivar had the highest extraction yield of 3% FW, followed by Xoan (2.9%), Sanh (2.2%), and Navel (1%). The chemical composition of the EOs was similar, with limonene as the main compound (around 96%). The antifungal activity of EOs was not different, with a minimum fungicidal concentration of 16% for both fungi. The disease inhibition of EOs increased with their concentration. The highest inhibition of anthracnose caused by both fungi on mangoes was achieved at 16% EO. EOs had no adverse effect on mango quality (pH, total soluble solids, total acidity, color and brightness of mangoes), except firmness and weight loss at high concentrations (16%). Orange EOs can be used as bio-fungicides to control mango anthracnose at high concentrations.
Water and Nitrogen Coupling on the Regulation of Soil Nutrient–Microbial Biomass Balance and Its Effect on the Yield of Wolfberry (Lycium barbarum L.)
Authors: Yin Juan , Ma Zhenghu , Yang Yingpan , Du Bin , Sun Fubin , Yang Zhen
Published: July 2023

Due to the problems of relatively fragile stability, the quality of soil in the drip-irrigated agricultural ecosystem has high spatial heterogeneity and experiences significant degradation. We conducted a two-year field plot study (2021–2022) in a typical region of the arid zone with the “wolfberry” crop as the research object, with three irrigation and three nitrogen application levels, and the local conventional management as the control (CK). Soil quality under experimental conditioning was comprehensively evaluated based on Principal Component Analysis (PCA) and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS), and regression analyses were carried out between the soil quality evaluation results and wolfberry yield. The results showed that short-term water and nitrogen regulation enhanced the soil nutrient content in the root zone of wolfberry to some extent, but it did not significantly affect soil carbon:soil nitrogen (Csoil:Nsoil), soil carbon:soil phosphorus (Csoil:Psoil), and soil nitrogen:soil phosphorus (Nsoil:Psoil). When the irrigation quota was increased from I1 to I2, the soil microbial biomass carbon, nitrogen, and phosphorus (Cmic, Nmic, and Pmic) tended to increase with the increase in N application, but the microbial biomass carbon:nitrogen (Cmic:Nmic), microbial biomass carbon:phosphorus (Cmic:Pmic), and microbial biomass nitrogen:phosphorus (Nmic:Pmic) did not change significantly. The comprehensive evaluation of the principal components and TOPSIS showed that the combined soil nutrient–microbial biomass and its ecological stoichiometry characteristics were better under the coupled treatments of I2, I3, N2, and N3, and the overall soil quality under these treatment conditions was significantly better than that under the CK treatment. Under I1 irrigation, nitrogen application significantly increased the yield of wolfberry, while under I2 and I3 irrigation, the wolfberry yield showed a parabolic trend with the increase in nitrogen application. The highest yield was recorded in the I2N2 treatment in the first and second years, with yields of 9967 kg hm−2 and 10,604 kg hm−2, respectively. The coefficient of determination (explained quantity) of the soil quality based on soil nutrient–microbial biomass and the characteristics of its ecological stoichiometry for wolfberry yield ranged from 0.295 to 0.573. These findings indicated a limited positive effect of these indicators of soil on wolfberry yield. The short-term water and nitrogen regulation partly influenced the soil and soil microbial biomass in agroecosystems, but the effect on elemental balance was not significant. Our findings might provide theoretical support for managing the health of agricultural ecosystems.