bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple Effects of Echinochrome A on Selected Ion Channels Implicated in Skin Physiology
Authors: Kim Sung , Chung Elina , Vasileva Elena , Mishchenko Natalia , Fedoreyev Sergey , Stonik Valentin , Kim Hyoung , Nam Joo , Kim Sung
Published: January 2023

Echinochrome A (Ech A), a naphthoquinoid pigment from sea urchins, is known to have anti-inflammatory and analgesic effects that have been suggested to be mediated by antioxidant activity and intracellular signaling modulation. In addition to these mechanisms, the ion channels in keratinocytes, immune cells, and nociceptive neurons may be the target for the pharmacological effects. Here, using the patch clamp technique, we investigated the effects of Ech A on the Ca2+-permeable TRPV3, TRPV1 and Orai1 channels and the two-pore domain K+ (K2P) channels (TREK/TRAAK, TASK-1, and TRESK) overexpressed in HEK 293 cells. Ech A inhibited both the TRPV3 and Orai1 currents, with IC50 levels of 2.1 and 2.4 μM, respectively. The capsaicin-activated TRPV1 current was slightly augmented by Ech A. Ech A alone did not change the amplitude of the TREK-2 current (ITREK2), but pretreatments with Ech A markedly facilitated ITREK2 activation by 2-APB, arachidonic acid (AA), and acidic extracellular pH (pHe). Similar facilitation effects of Ech A on TREK-1 and TRAAK were observed when they were stimulated with 2-APB and AA, respectively. On the contrary, Ech A did not affect the TRESK and TASK-1 currents. Interestingly, the ITREK2 maximally activated by the combined application of 2-APB and Ech A was not inhibited by norfluoxetine but was still completely inhibited by ruthenium red. The selective loss of sensitivity to norfluoxetine suggested an altered molecular conformation of TREK-2 by Ech A. We conclude that the Ech A-induced inhibition of the Ca2+-permeable cation channels and the facilitation of the TREK/TRAAK K2P channels may underlie the analgesic and anti-inflammatory effects of Ech A.
7S,15R-Dihydroxy-16S,17S-epoxy-docosapentaenoic Acid Overcomes Chemoresistance of 5-Fluorouracil by Suppressing the Infiltration of Tumor-Associated Macrophages and Inhibiting the Activation of Cancer Stem Cells in a Colorectal Cancer Xenograft Model
Authors: Su Yan , Choi Hack Sun , Choi Jong Hyun , Kim Hee-Sik , Jang Yong-Suk , Seo Jeong-Woo
Published: January 2023

Although the tumor bulk is initially reduced by 5-fluorouracil (5-FU), chemoresistance developed due to prolonged chemotherapy in colorectal cancer (CRC). The enrichment of cancer stem cells (CSCs) and the infiltration of tumor-associated macrophages (TAMs) contribute to chemoresistance and poor outcomes. A docosahexaenoic acid derivative developed by our group, 7S,15R-dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA), exerts antitumor effects against TAMs infiltration and CSCs enrichment in our previous study. The current study aimed to investigate whether diHEP-DPA was able to overcome chemoresistance to 5-FU in CRCs, together with the potential synergistic mechanisms in a CT26-BALB/c mouse model. Our results suggested that although 5-FU inhibited tumor growth, 5-FU enriched CSCs via the WNT/β-catenin signaling pathway, resulting in chemoresistance in CRCs. However, we revealed that 5-FU promoted the infiltration of TAMs via the NF-kB signaling pathway and improved epithelial–mesenchymal transition (EMT) via the signal transducer and activator of the transcription 3 (STAT3) signaling pathway; these traits were believed to contribute to CSC activation. Furthermore, supplementation with diHEP-DPA could overcome drug resistance by decreasing the CSCs, suppressing the infiltration of TAMs, and inhibiting EMT progression. Additionally, the combinatorial treatment of diHEP-DPA and 5-FU effectively enhanced phagocytosis by blocking the CD47/signal regulatory protein alpha (SIRPα) axis. These findings present that diHEP-DPA is a potential therapeutic supplement to improve drug outcomes and suppress chemoresistance associated with the current 5-FU-based therapies for colorectal cancer.
Design, Synthesis and Structure-Activity Relationship Studies of Nicotinamide Derivatives as Potent Antifungal Agents by Disrupting Cell Wall
Authors: Ni Tingjunhong , Xie Fei , Li Liping , Hao Yumeng , Chi Xiaochen , Yan Lan , Zhang Dazhi , Jiang Yuanying , Lv Quanzhen
Published: January 2023

Fungal infections pose a serious challenge to human health due to the limited paucity of antifungal treatments. Starting as a hit compound screened from our compound library, a series of nicotinamide derivatives have been successfully synthesized via a facile one-step coupling reaction of aromatic carboxylic acid and amine. The synthesized compounds were evaluated for their antifungal activity against Candida albicans SC5314. Among the 37 nicotinamide derivatives screened, compound 16g was found to be the most active against C. albicans SC5314, with an MIC value of 0.25 μg/mL and without significant cytotoxicity. The rudimentary structure-activity relationships study revealed that the position of the amino and isopropyl groups of 16g was critical for its antifungal activity. In particular, compound 16g showed potent activity against six fluconazole-resistant C. albicans strains with MIC values ranging from 0.125–1 μg/mL and showed moderate activity against the other seven species of Candida, three strains of Cryptococcus neoformans, and three strains of Trichophyton. Furthermore, compound 16g showed fungicidal, anti-hyphal, and anti-biofilm activities in vitro, which were related to its ability to disrupt the cell wall of C. albicans. Taken together, 16g is a promising compound that is fungal-specific by targeting the cell wall and could be used as a lead compound for further investigation.
Investigation of the Interaction of Benzo(a)Pyrene and Fluoranthene with Cucurbit[n]urils (n = 6–8): Experimental and Molecular Dynamic Study
Authors: Elbashir Abdalla A. , Alfadil Amira A. , Suliman FakhrEldin O. , Alnajjar Ahmed O.
Published: January 2023

The inclusion complexes of cucurbit[n]uril, CB[n] (n = 6–8), with poly aromatic hydrocarbon (PAH) Benzo(a)Pyrene (BaP), and fluoranthene (FLT) were investigated carefully in aqueous media. Fluorescence and 1H NMR spectroscopy were used to characterize and investigate the inclusion complexes that were prepared in the aqueous media. The most predominant complexes of both guests with hosts were the 1:1 guest: host complexes. Stability constants of 2322 ± 547 M−1, 7281 ± 689 M−1, 3566 ± 473 M−1 were obtained for the complexes of BaP with CB[6], CB[7], and CB[8], respectively. On the other hand, stability constants of 5900.270 ± 326 M−1, 726.87 ± 78 M−1, 3327.059 ± 153 M−1 were obtained for the complexes of FLT with CB[6], CB[7], and CB[8], respectively. Molecular dynamic (MD) simulations were used to study the mode and mechanism of the inclusion process and to monitor the stability of these complexes in aqueous media at an atomistic level. Analysis of MD trajectories has shown that both BaP and FLT form stable inclusion complexes with CB[7] and CB[8] in aqueous media throughout the simulation time, subsequently corroborating the experimental results. Nevertheless, the small size of CB[6] prohibited the encapsulation of the two PAHs inside the cavity, but stable exclusion complex was observed between them. The main driving forces for the stability of these complexes are the hydrophobic forces, van der Waals interactions, electrostatic effect, the π····π and C–H···π interaction. These results suggest that BaP and FLT can form stable complexes with CB[n] (n = 6–8) in solution.
In Vitro Anticancer Activity of Novel Ciprofloxacin Mannich Base in Lung Adenocarcinoma and High-Grade Serous Ovarian Cancer Cell Lines via Attenuating MAPK Signaling Pathway
Authors: Fawzy Michael A. , Abu-baih Rania H. , Abuo-Rahma Gamal El-Din A. , Abdel-Rahman Islam M. , El-Sheikh Azza A. K. , Nazmy Maiiada H.
Published: January 2023

Novel drugs are desperately needed in order to combat a significant challenge due to chemo-therapeutic resistance and bad prognosis. This research aimed to assess the anticancer activity of a newly synthesized ciprofloxacin Mannich base (CMB) on ovarian cancer (OVCAR-3) and lung cancer (A-549) cell lines and to investigate probable involved molecular mechanisms. The cytotoxic and pro-apoptotic impact of CMB on both cell lines was investigated using MTT assay, Annexin V assay, and cell cycle analysis, as well as caspase-3 activation. Western blotting was carried out to evaluate downstream targets of the MAPK pathway, while qRT PCR was used to evaluate the gene expression pattern of the p53/Bax/Bcl2 pathway. CMB treatment showed significantly reduced cell proliferation in both OVCAR-3 and A-549 cells with half maximum inhibitory concentration (IC50) = 11.60 and 16.22 µg/mL, respectively. CMB also induced apoptosis, S phase cell cycle arrest, and up-regulated expression of p53, p21, and Bax while down-regulated Bcl2 expression. CMB also halted cell proliferation by deactivating the MAPK pathway. In conclusion, CMB may be regarded as a potential antiproliferative agent for lung and ovarian cancers due to anti-proliferative and pro-apoptotic actions via inhibition of the MAPK pathway and p53/Bax/Bcl2.
In Situ Hydrothermal Synthesis of Ni1−xMnxWO4 Nanoheterostructure for Enhanced Photodegradation of Methyl Orange
Authors: Hasan Imran , Albaeejan Mohammed Abdullah , Alshayiqi Alanoud Abdullah , Al-Nafaei Wedyan Saud , Alharthi Fahad A.
Published: January 2023

The monoclinic nanocrystalline Ni1−xMnxWO4 heterostructure has been successfully synthesized by the hydrothermal technique for achieving better sensitive and photocatalytic performances. Different characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV–Vis), and photoluminescence (PL) spectroscopy have been employed to investigate their structural, microstructural, and optical properties. Mn-ion incorporation in the NiWO4 lattice reduces the particle size of the sample compared with the pure undoped NiWO4 sample, which has been confirmed from the transmission electron microscope image. The Tauc plot of the Ni1−xMnxWO4 sample exhibits a significant decrease in bandgap energy compared with the pure undoped NiWO4 sample due to the quantum confinement effect. Finally, the material was explored as a photocatalyst for the degradation of methyl orange (MO) dye from wastewater under visible light irradiation. Various reaction parameters such as pH, catalyst dose, reaction time, and kinetics of the photodegradation were studied using the batch method. The results showed that the Ni1−xMnxWO4 is highly efficient (94.51%) compared with undoped NiWO4 (65.45%). The rate of photodegradation by Ni1–xMnxWO4 (0.067) was found to be 1.06 times higher than the undoped NiWO4 (0.062).
A Review of the Regulatory Mechanisms of N-Myc on Cell Cycle
Authors: Li Hong-Li , Dong Lu-Lu , Jin Min-Jie , Li Qian-Yu , Wang Xiao , Jia Mei-Qi , Song Jian , Zhang Sai-Yang , Yuan Shuo
Published: January 2023

Neuroblastoma has obvious heterogeneity. It is one of the few undifferentiated malignant tumors that can spontaneously degenerate into completely benign tumors. However, for its high-risk type, even with various intensive treatment options, the prognosis is still unsatisfactory. At the same time, a large number of research data show that the abnormal amplification and high-level expression of the MYCN gene are positively correlated with the malignant progression, poor prognosis, and mortality of neuroblastoma. In this context, this article explores the role of the N-Myc, MYCN gene expression product on its target genes related to the cell cycle and reveals its regulatory network in promoting tumor proliferation and malignant progression. We hope it can provide ideas and direction for the research and development of drugs targeting N-Myc and its downstream target genes.
Antimicrobial Natural Products from Plant Pathogenic Fungi
Authors: Cadelis Melissa M. , Li Steven A. , van de Pas Shara J. , Grey Alex , Mulholland Daniel , Weir Bevan S. , Copp Brent R. , Wiles Siouxsie
Published: January 2023

Isolates of a variety of fungal plant pathogens (Alternaria radicina ICMP 5619, Cercospora beticola ICMP 15907, Dactylonectria macrodidyma ICMP 16789, D. torresensis ICMP 20542, Ilyonectria europaea ICMP 16794, and I. liriodendra ICMP 16795) were screened for antimicrobial activity against the human pathogenic bacteria Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, Mycobacterium abscessus, and M. marinum and were found to have some activity. Investigation of the secondary metabolites of these fungal isolates led to the isolation of ten natural products (1–10) of which one was novel, (E)-4,7-dihydroxyoct-2-enoic acid (1). Structure elucidation of all natural products was achieved by a combination of NMR spectroscopy and mass spectrometry. We also investigated the antimicrobial activity of a number of the isolated natural products. While we did not find (E)-4,7-dihydroxyoct-2-enoic acid (1) to have any activity against the bacteria and fungi in our assays, we did find that cercosporin (7) exhibited potent activity against Methicillin resistant Staphylococcus aureus (MRSA), dehydro-curvularin (6) and radicicol (10) exhibited antimycobacterial activity against M. marinum, and brefeldin A (8) and radicicol (10) exhibited antifungal activity against Candida albicans. Investigation of the cytotoxicity and haemolytic activities of these natural products (6–8 and 10) found that only one of the four active compounds, radicicol (10), was non-cytotoxic and non-haemolytic.
Targeted Quantification of Protein Phosphorylation and Its Contributions towards Mathematical Modeling of Signaling Pathways
Authors: Dakup Panshak P. , Feng Song , Shi Tujin , Jacobs Jon M. , Wiley H. Steven , Qian Wei-Jun
Published: January 2023

Post-translational modifications (PTMs) are key regulatory mechanisms that can control protein function. Of these, phosphorylation is the most common and widely studied. Because of its importance in regulating cell signaling, precise and accurate measurements of protein phosphorylation across wide dynamic ranges are crucial to understanding how signaling pathways function. Although immunological assays are commonly used to detect phosphoproteins, their lack of sensitivity, specificity, and selectivity often make them unreliable for quantitative measurements of complex biological samples. Recent advances in Mass Spectrometry (MS)-based targeted proteomics have made it a more useful approach than immunoassays for studying the dynamics of protein phosphorylation. Selected reaction monitoring (SRM)—also known as multiple reaction monitoring (MRM)—and parallel reaction monitoring (PRM) can quantify relative and absolute abundances of protein phosphorylation in multiplexed fashions targeting specific pathways. In addition, the refinement of these tools by enrichment and fractionation strategies has improved measurement of phosphorylation of low-abundance proteins. The quantitative data generated are particularly useful for building and parameterizing mathematical models of complex phospho-signaling pathways. Potentially, these models can provide a framework for linking analytical measurements of clinical samples to better diagnosis and treatment of disease.
The Effect of Alkali Iodide Salts in the Inclusion Process of Phenolphthalein in β-Cyclodextrin: A Spectroscopic and Theoretical Study
Authors: Kouderis Constantine , Tsigoias Stefanos , Siafarika Panagiota , Kalampounias Angelos G.
Published: January 2023

The formation of the inclusion complex between β-cyclodextrin (CD) and phenolphthalein (PP) was investigated by means of UV–Vis and FT-IR spectroscopies. The thermodynamic parameters were calculated in the absence and presence of LiI, KI, NaI and CsI iodide salts. The enthalpy change during the formation was found to be negative for all solutions with iodide salts. The enthalpy change was found to decrease in the sequence no salt > NaI > KI> CsI > LiI. Moreover, it was observed that with increasing salt concentration enthalpy decreases monotonically. The interaction between the two molecules was mostly attributed to hydrogen bonding and Van der Waals interactions. Thermodynamic properties revealed that electrostatic forces also contribute when LiI is present in solutions. A molecular docking study was performed to elucidate the docking between phenolphthalein and cyclodextrin. The FT-IR spectra of CD, PP and the CD–PP complex were recorded to establish the formation of the inclusion complex. Semi-empirical and DFT methods were utilized to study theoretically the complexation process and calculate the IR vibrational spectra. The adequate agreement between theoretical and experimental results supports the proposed structural model for the CD–PP complexation.
Anti-Cancer Peptides: Status and Future Prospects
Authors: Ghaly Gehane , Tallima Hatem , Dabbish Eslam , Badr ElDin Norhan , Abd El-Rahman Mohamed K. , Ibrahim Mahmoud A. A. , Shoeib Tamer
Published: January 2023

The dramatic rise in cancer incidence, alongside treatment deficiencies, has elevated cancer to the second-leading cause of death globally. The increasing morbidity and mortality of this disease can be traced back to a number of causes, including treatment-related side effects, drug resistance, inadequate curative treatment and tumor relapse. Recently, anti-cancer bioactive peptides (ACPs) have emerged as a potential therapeutic choice within the pharmaceutical arsenal due to their high penetration, specificity and fewer side effects. In this contribution, we present a general overview of the literature concerning the conformational structures, modes of action and membrane interaction mechanisms of ACPs, as well as provide recent examples of their successful employment as targeting ligands in cancer treatment. The use of ACPs as a diagnostic tool is summarized, and their advantages in these applications are highlighted. This review expounds on the main approaches for peptide synthesis along with their reconstruction and modification needed to enhance their therapeutic effect. Computational approaches that could predict therapeutic efficacy and suggest ACP candidates for experimental studies are discussed. Future research prospects in this rapidly expanding area are also offered.
Fish By-Products: A Source of Enzymes to Generate Circular Bioactive Hydrolysates
Authors: Borges Sandra , Odila Joana , Voss Glenise , Martins Rui , Rosa Ana , Couto José António , Almeida André , Pintado Manuela
Published: January 2023

Fish viscera are usually discarded as waste, causing environmental problems, or as low-value by-products. This study describes a self-sufficient and zero waste approach to obtain enzymes and protein hydrolysates from fish by-products. Firstly, recovery steps of viscera enzymatic extract were applied, and the resulting raw extract was stable at a pH range of 8–9 and at temperatures between 40 and 50 °C. The application of the extracted enzymes and alcalase on fish by-products hydrolysis was also determined. The selected conditions for the enzymatic hydrolysis were 10% (E/S) for 6 h using viscera enzymatic extract and 3% (E/S) for 2 h using alcalase. Fish protein hydrolysates (FPH) proved to have a notable antioxidant capacity with similar activity, ~11 mg ascorbic acid/g dry extract (ABTS assay) and ~150 mg Trolox/g dry extract (ORAC assay). FPH were also able to inhibit the angiotensin-converting enzyme, however, alcalase hydrolysates revealed a higher antihypertensive potential, IC50 of 101 µg of protein/mL. In general, FPH obtained by both enzymes systems maintained these bioactivities after the passage throughout a simulated gastrointestinal tract. The hydrolysates also displayed important technological properties, namely oil absorption capacity (~1 g oil/g sample) and emulsifying property (~40%). Therefore, it will be conceivable to use fish by-products based on a circular economy approach to generate added value compounds for animal and human nutrition.
Roles of G4-DNA and G4-RNA in Class Switch Recombination and Additional Regulations in B-Lymphocytes
Authors: Dézé Ophélie , Laffleur Brice , Cogné Michel
Published: January 2023

Mature B cells notably diversify immunoglobulin (Ig) production through class switch recombination (CSR), allowing the junction of distant “switch” (S) regions. CSR is initiated by activation-induced deaminase (AID), which targets cytosines adequately exposed within single-stranded DNA of transcribed targeted S regions, with a specific affinity for WRCY motifs. In mammals, G-rich sequences are additionally present in S regions, forming canonical G-quadruplexes (G4s) DNA structures, which favor CSR. Small molecules interacting with G4-DNA (G4 ligands), proved able to regulate CSR in B lymphocytes, either positively (such as for nucleoside diphosphate kinase isoforms) or negatively (such as for RHPS4). G4-DNA is also implicated in the control of transcription, and due to their impact on both CSR and transcriptional regulation, G4-rich sequences likely play a role in the natural history of B cell malignancies. Since G4-DNA stands at multiple locations in the genome, notably within oncogene promoters, it remains to be clarified how it can more specifically promote legitimate CSR in physiology, rather than pathogenic translocation. The specific regulatory role of G4 structures in transcribed DNA and/or in corresponding transcripts and recombination hereby appears as a major issue for understanding immune responses and lymphomagenesis.
Castasterone, a Plant Steroid Hormone, Affects Human Small-Cell Lung Cancer Cells and Reverses Multi-Drug Resistance
Authors: Sadava David , Chen Shiuan
Published: January 2023

Small-cell lung cancer (SCLC) has a dismal prognosis, in part because of the development of multi-drug resistance. Castasterone (CAS) is the metabolic precursor of the plant steroid hormone epibrassinolide (EB). In some plants, EB accounts for the total hormone activity, whereas in other plants, CAS is the active form. The effects of CAS, a BR present in most plants, on animal cells in general and cancer cells in particular have not been described. Here, we report the effects of CAS on drug-sensitive (H69) and drug-resistant (VPA17) SCLC cells. CAS was equally cytotoxic to both cell lines (IC50 = 1 μM), indicating a lack of cross-resistance. Pre-incubation of VPA17 cells with CAS for 96 h reversed drug resistance to etoposide and doxorubicin. Synergism between CAS and EB, as well as with chemotherapy drugs, was investigated by exposure of VPA17 cells to 1:1 ratios of CAS and the other drugs at the respective IC50 values, with dilutions at 0.25 to 2.0 × IC50 and determination of the combination index (CI). CAS and EB were additive, indicating that the two drugs act on the same pathway, whereas CAS–etoposide (CI = 0.77) and CAS–doxorubicin were synergistic, indicating that CAS and the two chemotherapeutic drugs act on different pathways. Apoptosis in SCLC cells was measured by immuno-detection of single-strand DNA breaks. Following 96 h incubation of SCLC H69 cells in CAS, the level of DNA breaks was similar to measurements made after incubation in EB and etoposide, indicating that CAS is pro-apoptotic. Incubation of SCLC cells in CAS led to a time-dependent reduction (by 80%) in the transcriptional activator β-catenin. These data indicate that CAS may act via Wnt signaling. Taken together, our study reveals that CAS is pharmacologically active in both drug-sensitive and drug-resistant SCLC cells.
Multiple Sea Ice Type Retrieval Using the HaiYang-2B Scatterometer in the Arctic
Authors: Han Lu , Chen Haihua , Guan Lei , Li Lele
Published: January 2023

Sea ice type classification is of great significance for the exploration of waterways, fisheries, and offshore operations in the Arctic. However, to date, there is no multiple remote sensing method to detect sea ice type in the Arctic. This study develops a multiple sea ice type algorithm using the HaiYang-2B Scatterometer (HY-2B SCA). First, the parameters most applicable to classify sea ice type are selected through feature extraction, and a stacking model is established for the first time, which integrates decision tree and image segmentation algorithms. Finally, multiple sea ice types are classified in the Arctic, comprising Nilas, Young Ice, First Year Ice, Old Ice, and Fast Ice. Comparing the results with the Ocean and Sea Ice Satellite Application Facility (OSI-SAF) Sea Ice Type dataset (SIT) indicates that the sea ice type classified by HY-2B SCA (Stacking-HY2B) is similar to OSI-SAF SIT with regard to the changing trends in extent of sea ice. We use the Copernicus Marine Environment Monitoring Service (CMEMS) high-resolution sea ice type data and EM-Bird ice thickness data to validate the result, and accuracies of 87% and 88% are obtained, respectively. This indicates that the algorithm in this work is comparable with the performance of OSI-SAF dataset, while providing information of multiple sea ice types.
Motion Error Estimation and Compensation of Airborne Array Flexible SAR Based on Multi-Channel Interferometric Phase
Authors: Yang Ling , Zhang Fubo , Sun Yihong , Chen Longyong , Li Zhenhua , Wang Dawei
Published: January 2023

Airborne array synthetic aperture radar (SAR) has made a significant breakthrough in the three-dimensional resolution of traditional SAR. In the airborne array SAR 3D imaging technology, the baseline length is the main factor restricting the resolution. Airborne array flexible SAR can increase the baseline length to improve the resolution and interference performance by mounting antennae on the wing. The existing research lacks results obtained using flexible actual data processing and specific motion compensation methods. Thus, this paper proposes a motion error estimation and compensation method for an airborne array flexible SAR based on a multi-channel interferometric phase. Firstly, a flexible channel motion compensation model is established based on the multi-channel interference phase of airborne array flexible SAR. Then, based on the rigid multi-channel data, combined with the ground control points, the least square method, and the global optimal search algorithm, the accurate rigid baseline length and the central incidence angle are obtained. Finally, according to the multi-channel interference phase inversion of the flexible motion error and combined with the motion compensation model, the flexible data are compensated in the time domain. The actual results indicate that, compared with traditional motion compensation methods, our method can obtain accurate flexible compensation data. This study improves the interference performance of multi-channel data of airborne array flexible SAR and lays a solid foundation for the high-precision 3D reconstruction of airborne array flexible SAR.
Revisiting Link Quality Metrics and Models for Multichannel Low-Power Lossy Networks
Authors: Mao Jing , Zhao Yan , Xia Yu , Yang Zhuopeng , Xu Cheng , Liu Wei , Huang Daqing
Published: January 2023

Multichannel communication has great potential in environments with unknown interference patterns. However, existing link quality metrics and models are generally established and verified under a single-channel scenario, which does not consider the impacts of radio interference and channel change. Therefore, it is hard to directly judge whether these metrics and models are still valid under a multichannel scenario. This paper empirically analyzes the applicability of popular link quality metrics and models in multiple channels with different interference levels. Results show that the link quality estimation (LQE) capability of traditional metrics will be affected by the interference level of the channel, which makes the conclusions obtained under a single-channel scenario no longer valid. Meanwhile, traditional LQE models are basically not adaptive to radio interference and channel change. They are only valid for channels with similar interference under which they are modeled. If these models are directly used under a multichannel scenario, the link quality will be overestimated inevitably. In other words, traditional LQE metrics and models cannot be directly used in the multichannel scenario. It is necessary to deeply analyze the statistical characteristics of popular link quality metrics in multiple typical channels and design channel and interference adaptive metrics and models to support effective multichannel communication.
rGO-PDMS Flexible Sensors Enabled Survival Decision System for Live Oysters
Authors: Liu Pengfei , Zhang Luwei , Li You , Feng Huanhuan , Zhang Xiaoshuan , Zhang Mengjie
Published: January 2023

The shell-closing strength (SCS) of oysters is the main parameter for physiological activities. The aim of this study was to evaluate the applicability of SCS as an indicator of live oyster health. This study developed a flexible pressure sensor system with polydimethylsiloxane (PDMS) as the substrate and reduced graphene oxide (rGO) as the sensitive layer to monitor SCS in live oysters (rGO-PDMS). In the experiment, oysters of superior, medium and inferior grades were selected as research objects, and the change characteristics of SCS were monitored at 4 °C and 25 °C. At the same time, the time series model was used to predict the survival rate of live oyster on the basis of changes in their SCS characteristics. The survival times of superior, medium and inferior oysters at 4 °C and 25 °C were 31/25/18 days and 12/10/7 days, respectively, and the best prediction accuracies for survival rate were 89.32%/82.17%/79.19%. The results indicate that SCS is a key physiological indicator of oyster survival. The dynamic monitoring of oyster vitality by means of flexible pressure sensors is an important means of improving oyster survival rate. Superior oysters have a higher survival rate in low-temperature environments, and our method can provide effective and reliable survival prediction and management for the oyster industry.
Redundant Fault Diagnosis for Photovoltaic Systems Based on an IRT Low-Cost Sensor
Authors: Ochoa Joan , García Emilio , Quiles Eduardo , Correcher Antonio
Published: January 2023

In large solar farms, supervision is an exhaustive task, often carried out manually by field technicians. Over time, automated or semi-automated fault detection and prevention methods in large photovoltaic plants are becoming increasingly common. The same does not apply when talking about small or medium-sized installations, where the cost of supervision at such level would mean total economic infeasibility. Although there are prevention protocols by suppliers, periodic inspections of the facilities by technicians do not ensure that faults such as the appearance of hot-spots are detected in time. That is why, nowadays, the only way of continuous supervision of a small or medium installation is often carried out by unqualified people and in a purely visual way. In this work, the development of a low-cost system prototype is proposed for the supervision of a medium or small photovoltaic installation based on the acquisition and treatment of thermographic images, with the aim of investigating the feasibility of an actual implementation. The work focuses on the system’s ability to detect hot-spots in supervised panels and successfully report detected faults. To achieve this goal, a low-cost thermal imaging camera is used for development, applying common image processing techniques, operating with OpenCV and MATLAB R2021b libraries. In this way, it is possible to demonstrate that it is achievable to successfully detect the hottest points of a photovoltaic (PV) installation with a much cheaper camera than the cameras used in today’s thermographic inspections, opening up the possibilities of creating a fully developed low-cost thermographic surveillance system.
A Multiplex Molecular Cell-Based Sensor to Detect Ligands of PPARs: An Optimized Tool for Drug Discovery in Cyanobacteria
Authors: Páscoa Inês , Biltes Rita , Sousa João , Preto Marco Aurélio Correia , Vasconcelos Vitor , Castro Luís Filipe , Ruivo Raquel , Cunha Isabel
Published: January 2023

Cyanobacteria produce a wealth of secondary metabolites. Since these organisms attach fatty acids into molecules in unprecedented ways, cyanobacteria can serve as a novel source for bioactive compounds acting as ligands for Peroxisome Proliferator-Activated Receptors (PPAR). PPARs (PPARα, PPARβ/δ and PPARγ) are ligand-activated nuclear receptors, involved in the regulation of various metabolic and cellular processes, thus serving as potential drug targets for a variety of pathologies. Yet, given that PPARs’ agonists can have pan-, dual- or isoform-specific action, some controversy has been raised over currently approved drugs and their side effects, highlighting the need for novel molecules. Here, we expand and validate a cell-based PPAR transactivation activity biosensor, and test it in a screening campaign to guide drug discovery. Biosensor upgrades included the use of different reporter genes to increase signal intensity and stability, a different promoter to modulate reporter gene expression, and multiplexing to improve efficiency. Sensor’s limit of detection (LOD) ranged from 0.36–0.89 nM in uniplex and 0.89–1.35 nM in multiplex mode. In triplex mode, the sensor’s feature screening, a total of 848 fractions of 96 cyanobacteria extracts were screened. Hits were confirmed in multiplex mode and in uniplex mode, yielding one strain detected to have action on PPARα and three strains to have dual action on PPARα and -β.
Bioactivities Screening and Elucidation of Terpenoid from the Stembark Extracts of Lansium domesticum Corr. cv. Kokosan (Meliaceae)
Authors: Sinaga Siska , Fajar Mohamad , Mayanti Tri , Supratman Unang
Published: January 2023

Lansium domesticum Corr. (L. domesticum), Meliaceae, has an economical fruit found throughout the southeast and has been reported to be used in traditional medicine. Therefore, this study aims to investigate the antimicrobial and cytotoxic potential of four extracts from the stembark of L. domesticum Corr. cv. Kokossan and isolated four terpenoid compounds. Antimicrobial testing was performed on two fungi, namely Malassezia furfur and Candida albicans, and two bacteria, Staphylococcus epidermidis and Klebsiella pneumoniae. Furthermore, antimicrobial activity was determined using the minimum inhibitory concentration (MIC). All isolated extracts were also tested on MCF-7 breast cancer cells. The results showed that butanol and n-hexane extracts have antimicrobial potential against K. pneumoniae bacteria with MIC values of 7.8125 mg/mL and 62.5 mg/mL, respectively, as well as against the dandruff fungus M. furfur. In addition to the antimicrobial results, the anticancer test results also showed that n-hexane has the most interesting cytotoxic value of all extracts, with an IC50 of 42.95 µg/mL than extracts of ethyl acetate, ethanol, and butanol with respective IC50 values of 72.84; 74.50, and 12088.33 µg/mL. The n-hexane and n-butanol extracts have anticancer and antimicrobial potential. These extracts can be studied further for other bioactivity.
Spatial Vitality Evaluation and Coupling Regulation Mechanism of a Complex Ecosystem in Lixiahe Plain Based on Multi-Source Data
Authors: Gong Yaxi , Ji Xiang , Zhang Yuan , Cheng Shanshan
Published: January 2023

[Purpose] With the acceleration of China’s urbanization process and the construction of the metropolitan area, the polarization phenomenon (Matthew effect) between cities and cities, cities and villages, and villages and villages has become increasingly prominent, and the relationship between urban and rural construction elements such as economy, society, nature, and population has become increasingly complex. However, due to the huge differences between cities and villages, it is difficult to use a unified “measuring ruler” to compare them horizontally and vertically in the space–time dimension. Therefore, it is necessary to evaluate and measure the spatial vitality of each administrative unit in the region from the perspective of urban development, that is, the sustainable development capacity of space. [Method] Taking Lixiahe Plain as the research object, based on the multi-source data such as POI, night-time light, and land use/cover, on the one hand, the spatial vitality evaluation system of the complex ecosystem is constructed, and the vitality levels and types of different township units are divided. On the other hand, the coupling degree model, coupling degree coordination degree model, spatial correlation analysis, and exploratory space–time data analysis are used to analyze the complex relationship and dynamic evolution characteristics of interaction stress among the spatial vitality of township units. [Conclusion] (1) The spatial vitality status is generally good, but there are great differences among regions, and the trend of fluctuant declines from west to east, and the spatial vitality type is a mainly vigorous type and development type. (2) There is a strong spatial dependence among the subsystems of the township units in the region. The spatial structure of the township units in the central area is more dynamic, while the spatial structure of the surrounding towns is more stable. (3) The 136 township units are divided into 4 different types of villages and towns, namely, coordinated evolution type, maladjustment evolution type, overall invariant type, and stable invariant type, which is conducive to putting forward their own development strategies.
Exploring the Antecedents of Supply Chain Viability in a Pandemic Context: An Empirical Study on the Commercial Flower Supply Chain of an Emerging Economy
Authors: Misbauddin S. M. , Alam Mohammad Jahangir , Karmaker Chitra Lekha , Nabi Md. Noor Un , Hasan Md. Mahedi
Published: January 2023

The global supply chain (SC) has faced unprecedented disruptions fueled by the COVID-19 virus. While scholarly research has explored various dimensions to counter the epidemic and bolster the SC, the literature is still dispersed and fragmented in managing the SC toward sustainable operational performance. We strengthened the notion of the SC by extending it toward the SC viability (SCV) approach. The objective of the study is to determine the factors to propose a model for sustainable SC viability in a pandemic context. We built our theoretical model based on the viable supply chain (VSC) theory. The study assessed the hypotheses using partial least square-based structural equation modelling with data from 428 flower-producing cum trading enterprises. The research found that supply chain integration and supply risk control positively influence ensuring SCV. Besides, supply chain resilience mediates the effect of SC integration and risk control on SCV. By exploring the role of SC integration, SC resilience, and SC risk control, the study contributes to SC viability theory. Our research fills the gap in the domain of SC viability dimension. From our study, the academicians and firms can get fresh antecedents of SC viability as an emerging sustainable SC management approach.
Potassium Simulation Using HYDRUS-1D with Satellite-Derived Meteorological Data under Boro Rice Cultivation
Authors: Gupta Ayushi , Gupta Manika , Srivastava Prashant K. , Petropoulos George P. , Singh Ram Kumar
Published: January 2023

Potassium (K) is a critical nutrient for crops, as it is a major constituent in fertilizer formulations. With increasing concentrations of K in agricultural soil, it is necessary to understand its movement and retention in the soil. Sub-surface modeling is an alternative method to overcome the exhausting and uneconomical methods to study and determine the actual concentration of K in soil. HYDRUS-1D is considered an effective finite-element model which is suitable for sub-surface modeling. This model requires the input of ground-station meteorological (GM) data taken at a daily timestep for the simulation period. It can be a limiting factor in the absence of ground stations. The study compares K predictions in surface and sub-surface soil layers under Boro rice cultivation obtained with the usage of different meteorological datasets. Thus, the main hypothesis of the study was to validate that, in the absence of GM data, satellite-based meteorological data could be utilized for simulating the K concentration in soil. The two meteorological datasets that are considered in the study included the GM and satellite-derived NASA-Power (NP) meteorological datasets. The usage of a satellite meteorological product at a field scale may help in applying the method to other regions where GM data is not available. The numerical model results were validated with field experiments from four experimental fields which included varied K doses. The concentration in soil was assessed at the regular depths (0–5, 5–10, 10–15, 15–30, 30–45 and 45–60 cm), and at various stages of crop growth, from bare soil and sowing, to the tillering stages. The concentration of K was measured in the laboratory and also simulated through the optimized model. The modeled values were compared with measured values statistically using relative root mean square error (RMSER) and Nash–Sutcliffe modeling efficiency (E) for simulating K concentration in the soil for the Boro rice cropping pattern with both GM data and NP data. The model was found most suitable for the 0–30 cm depth on all days and for all treatment variations.
Drivers Enabling Developing Countries to Enter High-Tech Production Networks through Global Production Sharing: Evidence from Malaysia, Taiwan, and Vietnam
Authors: Jayasinghe Shan , Johnson Lester W. , Udayanga Nilan , Kumarapperuma Lakshitha , Ranjitha Sanath
Published: January 2023

Since the 1960s, the world has witnessed the rise of several East Asian nations as economic powerhouses. One of the main contributing factors of their success is their decision to create policies that allowed them to enter high-tech global production networks. Today, other countries are attempting to do the same by replicating the success of these East Asian nations, but they have had considerably less success. Thus, a study that investigates the drivers of developing countries entering global production networks would be of great use to policymakers in other countries. Hence, with the support of evidence from Vietnam, Malaysia, and Taiwan, this study proposes policy options (government support, science parks, tax, and other incentives, high- and semi-skilled labor, infrastructure development roadmaps, and free trade agreements) that are necessary to initiate and drive the entrance of a developing country into high-tech global production networks. Government support was identified as the main driver that determines the outcome of an effort to enter. Infrastructure development roadmap and free trade agreements were identified as optional. However, it is recommended that governments consider the two optional factors during policy formation, as they could complement the other factors.
New Failure Mechanism for Evaluating the Inclined Failure Load Adjacent to Undrained Soil Slope
Authors: Fang Hongwei , Xu Yixiang
Published: January 2023

The failure mechanism is the key problem for calculating the inclined failure loads adjacent to the undrained soil slope. Based on the undrained slip line field and boundary value problems, a new failure mechanism is proposed to evaluate the inclined failure loads adjacent the undrained slope. The rationality of the proposed method is proved by the definition of the ultimate load and the finite element upper bound analysis (FE-UB). It is not reasonable to assume the failure models since the failure models vary with the inclination load and angle. The proposed method gives a new evaluating indicator, which first calculates the inclined failure load and then determines the failure models.
Recent Advances in Marine Environmental Research
Authors: Young Chih-Chieh
Published: January 2023

The marine environment includes the waters of seas and estuaries, the seabed and its subsoils, and all marine wildlife and its sea and coastal habitats [...]
Quality identification examination of chicken eggs by morphological and physical parameters
Authors:   Department of Customs and Goods Examination, Donetsk National University of Economics and Trade named after Mykhailo Tugan-Baranovsky, Molokanova L.V. , Domenko А.А. ,   Department of Customs and Goods Examination, Donetsk National University of Economics and Trade named after Mykhailo Tugan-Baranovsky
Published: January 2023

The article presents the results of a quality identification examination of chicken eggs sold on the domestic market of the Donetsk People's Republic, according to morphological and physical parameters
Goutweed nutritional value and its use for food purposes
Authors:   Military Academy of Air and Space Defense named after Marshal of the Soviet Union G.K. Zhukov, Rodionova A. E.
Published: January 2023

The article discusses the use of a wild-growing species of goutweed. Its nutritional value and active substances are described, and recipes for goutweed dishes are given, which allow considering this plant from the perspective of a functional additive in culinary recipes.
Siberian sturgeon Acipenser baerii (Acipenseridae) of the Yenisei river. Part 2. Herd structure, demography, fishing (overview)
Authors:   Krasnoyarsk State Agrarian University, Russia, Krasnoyarsk, Zadelenov V.A. ,   Krasnoyarsk branch of the All-Russian Research Institute of Fisheries and Oceanography (NIIERV), Russia, Krasnoyarsk, Chetvertakova E.V. ,   Krasnoyarsk State Agrarian University, Russia, Krasnoyarsk, Alekseeva E.A. ,   Krasnoyarsk State Agrarian University, Russia, Krasnoyarsk, Zadelenova A.V. ,   Krasnoyarsk State Agrarian University, Russia, Krasnoyarsk
Published: January 2023

The analysis of publications available in open sources in the field of fishery research of the Siberian sturgeon in the basin of the river was carried out. Yenisei. Late sexual maturation of this species has been recorded: males become sexually mature at the age of 17–19 years, females mature at the age of 20–24 years. The intervals between successive spawnings in females are 5–6 years, males — 3–4. Absolute individual fecundity ranges from 50 to 750 thousand eggs. By the nature of the diet of sturgeon in the basin of the river. The Yenisei is a benthophage that consumes the larvae of chironomids, caddisflies, stoneflies, mayflies, midges, amphipods, and oligochaetes. Age and sex differences in nutrition are not observed. Information about the organization of sturgeon fishing on the river is given. Yenisei since the middle of the 19th century. The main share of the prey of this species fell on the lower reaches of the river; the catch of the spawning part of the population during the spawning migration brought about 10% of the total prey. It is noted that large-scale anthropogenic impacts have significantly changed the habitat of this species. The number and stocks of the Siberian sturgeon in the basin of the river. The Yenisei was noticeably reduced by the beginning of the 21st century. The Siberian sturgeon of the Yenisei population was included in the Red Book of the Russian Federation with conservation status II. Measures to preserve and increase the number of natural populations of the Siberian sturgeon in the basin of the river. Yenisei is carried out systematically.
Sakhalin Branch of the Federal State Budget Scientific Institution “Russian Federal Research Institute of Fisheries and oceanography” (SakhNIRO) is 90 years old
Authors:   Novosibirsk State Agrarian University, Novosibirsk, Russia, Pishchenko E.V.
Published: January 2023

In December 2022, one of the oldest fisheries institutes in Russia, the Sakhalin Branch of the Federal State Budget Scientific Institution “Russian Federal Research Institute of Fisheries and oceanography” (SakhNIRO) celebrated its 90th anniversary.