bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Interference Law of AC Transmission Lines on the Cathodic Protection Potential of Long-Distance Transmission Pipelines
Authors: Zhang Boyang , Li Lin , Zhang Yansong , Wang Jielin
Published: March 2023

Through inductive coupling, AC transmission lines can generate large amounts of voltage to buried oil and gas pipelines in areas with common corridors, posing a threat to the cathodic protection effect of pipelines. Therefore, this paper investigates the effect of AC transmission lines on the cathodic protection of long-distance pipelines through inductive coupling. COMSOL Multiphysics finite element simulation software is used to calculate the distribution of cathodic protection potential of long-distance pipelines under different voltage levels, parallel spacing, conductor-to-ground height, conductor arrangement and pipeline burial depth for normal operation of AC transmission lines. Comparison and analysis of the AC transmission line on the pipeline cathodic protection potential interference law is conducted. The results show that: 1. AC transmission lines cause serious electromagnetic interference with the pipeline cathodic protection system, which will cause the pipeline cathodic protection potential to shift out of the effective protection area. 2. The maximum value of the induced voltage of the pipeline will appear at the two ends of the pipeline, and the induced voltage of the pipeline in the middle position is 0. 3. The shift of the pipeline cathodic protection potential increases with the increase of voltage level and decreases with the increase of parallel spacing, conductor height and burial depth. The pipeline cathodic protection potential shift is highest when the wires are arranged horizontally and lowest when they are arranged in an umbrella shape.
An Inverse Optimal Value Approach for Synchronously Optimizing Activity Durations and Worker Assignments with a Project Ideal Cost
Authors: Zhang Lili , Chen Zhengrui , Shi Dan , Zhao Yanan
Published: March 2023

Most companies survive the pain of cost and schedule overruns because of inaccurate project activity time settings. In order to deliver a project with a target cost and on schedule, this research proposes an inverse optimal value approach to optimize activity durations and the corresponding worker assignments synchronously to make the optimal project cost infinitely close to an ideal cost. The leader model reflects cost orientation and adjustability of activity durations, the follower model reflects the complexity of activity sequence, critical path completion time, cost pressure, skill matching, energy consumption, and other costs. Through upper-level and lower-level feedback and interaction of activity durations and worker assignments it is possible to deliver a project with an ideal cost. With considerations of the mathematical model characteristics of bi-level programming, nonlinearity, NP hard, and MAX functions, an improved genetic algorithm combining adaptive artificial fish swarms is designed. From the comparison results of random examples and an actual example, the error rate of the optimal value of the improved algorithm is acceptable. Numerical experiments show that the inverse optimal approach can deliver a project without delay and with an ideal cost. The inverse optimization method is more in line with the idea of target management, and can help managers achieve the purpose of cost control.
Mathematical Model of a Main Rhythm in Limbic Seizures
Authors: Kornilov Maksim V. , Sysoev Ilya V.
Published: March 2023

While synchronization in the brain neural networks has been studied, the emergency of the main oscillation frequency and its evolution at different normal and pathological states remains poorly investigated. We propose a new concept of the formation of a main frequency in limbic epilepsy. The idea is that the main frequency is not a result of the activity of a single cell, but is formed due to collective dynamics in a ring of model neurons connected with delay. The individual cells are in an excitable mode providing no self-oscillations without coupling. We considered the ring of a different number of Hodgkin–Huxley neurons connected with synapses with time delay. We have shown that the proposed circuit can generate oscillatory activity with frequencies close to those experimentally observed. The frequency can be varied by changing the number of model neurons, time delay in synapses and coupling strength. The linear dependence of the oscillation period on both coupling delay and the number of neurons in the ring was hypothesized and checked by means of fitting the values obtained from the numerical experiments to the empirical formula for a constant value of coupling coefficient.
An Augmented Social Network Search Algorithm for Optimal Reactive Power Dispatch Problem
Authors: Sarhan Shahenda , Shaheen Abdullah , El-Sehiemy Ragab , Gafar Mona
Published: March 2023

Optimal Reactive Power Dispatch (ORPD) is one of the main challenges in power system operations. ORPD is a non-linear optimization task that aims to reduce the active power losses in the transmission grid, minimize voltage variations, and improve the system voltage stability. This paper proposes an intelligent augmented social network search (ASNS) algorithm for meeting the previous aims compared with the social network search (SNS) algorithm. The social network users’ dialogue, imitation, creativity, and disputation moods drive the core of the SNS algorithm. The proposed ASNS enhances SNS performance by boosting the search capability surrounding the best possible solution, with the goal of improving its globally searched possibilities while attempting to avoid getting locked in a locally optimal one. The performance of ASNS is evaluated compared with SNS on three IEEE standard grids, IEEE 30-, 57-, and 118-bus test systems, for enhanced results. Diverse comparisons and statistical analyses are applied to validate the performance. Results indicated that ASNS supports the diversity of populations in addition to achieving superiority in reducing power losses up to 22% and improving voltage profiles up to 90.3% for the tested power grids.
Impact of Imperfect Vaccine, Vaccine Trade-Off and Population Turnover on Infectious Disease Dynamics
Authors: Nyandjo Bamen Hetsron L. , Ntaganda Jean Marie , Tellier Aurelien , Menoukeu Pamen Olivier
Published: March 2023

Vaccination is an essential tool for the management of infectious diseases. However, many vaccines are imperfect, having only a partial protective effect in decreasing disease transmission and/or favouring recovery of infected individuals and possibly exhibiting a trade-off between these two properties. Furthermore, the success of vaccination also depends on the population turnover, and the rate of entry to and exit from the population. We here investigate by means of a mathematical model the interplay between these factors to predict optimal vaccination strategies. We first compute the basic reproduction number and study the global stability of the equilibria. We then assess the most influential parameters determining the total number of infected over time using a sensitivity analysis. We derive conditions for the vaccination coverage and efficiency to achieve disease eradication, assuming different intensities of population turnover (weak and strong), vaccine properties (transmission and/or recovery) and the trade-off between the latter. We show that the minimum vaccination coverage increases with lower population turnover decreases with higher vaccine efficiency (transmission or recovery) and is increased/decreased by up to 15% depending on the vaccine trade-off. We conclude that the coverage target for vaccination campaigns should be evaluated based on the interplay between these factors.
A Dendritic Neuron Model Optimized by Meta-Heuristics with a Power-Law-Distributed Population Interaction Network for Financial Time-Series Forecasting
Authors: Zhang Yuxin , Yang Yifei , Li Xiaosi , Yuan Zijing , Todo Yuki , Yang Haichuan
Published: March 2023

The famous McCulloch–Pitts neuron model has been criticized for being overly simplistic in the long term. At the same time, the dendritic neuron model (DNM) has been shown to be effective in prediction problems, and it accounts for the nonlinear information-processing capacity of synapses and dendrites. Furthermore, since the classical error back-propagation (BP) algorithm typically experiences problems caused by the overabundance of saddle points and local minima traps, an efficient learning approach for DNMs remains desirable but difficult to implement. In addition to BP, the mainstream DNM-optimization methods include meta-heuristic algorithms (MHAs). However, over the decades, MHAs have developed a large number of different algorithms. How to screen suitable MHAs for optimizing DNMs has become a hot and challenging area of research. In this study, we classify MHAs into different clusters with different population interaction networks (PINs). The performance of DNMs optimized by different clusters of MHAs is tested in the financial time-series-forecasting task. According to the experimental results, the DNM optimized by MHAs with power-law-distributed PINs outperforms the DNM trained based on the BP algorithm.
Multiview-Learning-Based Generic Palmprint Recognition: A Literature Review
Authors: Zhao Shuping , Fei Lunke , Wen Jie
Published: March 2023

Palmprint recognition has been widely applied to security authentication due to its rich characteristics, i.e., local direction, wrinkle, and texture. However, different types of palmprint images captured from different application scenarios usually contain a variety of dominant features. Specifically, the palmprint recognition performance will be degraded by the interference factors, i.e., noise, rotations, and shadows, while palmprint images are acquired in the open-set environments. Seeking to handle the long-standing interference information in the images, multiview palmprint feature learning has been proposed to enhance the feature expression by exploiting multiple characteristics from diverse views. In this paper, we first introduced six types of palmprint representation methods published from 2004 to 2022, which described the characteristics of palmprints from a single view. Afterward, a number of multiview-learning-based palmprint recognition methods (2004–2022) were listed, which discussed how to achieve better recognition performances by adopting different complementary types of features from multiple views. To date, there is no work to summarize the multiview fusion for different types of palmprint features. In this paper, the aims, frameworks, and related methods of multiview palmprint representation will be summarized in detail.
Periodically Intermittent Control of Memristor-Based Hyper-Chaotic Bao-like System
Authors: Li Kun , Li Rongfeng , Cao Longzhou , Feng Yuming , Onasanya Babatunde Oluwaseun
Published: March 2023

In this paper, based on a three-dimensional Bao system, a memristor-based hyper-chaotic Bao-like system is successfully constructed, and a simulated equivalent circuit is designed, which is used to verify the chaotic behaviors of the system. Meanwhile, a control method called periodically intermittent control with variable control width is proposed. The control width sequence in the proposed method is not only variable, but also monotonically decreasing, and the method can effectively stabilize most existing nonlinear systems. Moreover, the memristor-based hyper-chaotic Bao-like system is controlled by combining the proposed method with the Lyapunov stability principle. Finally, we should that the proposed method can effectively control and stabilize not only the proposed hyper-chaotic system, but also the Chua’s oscillator.
Delay-Dependent Stability Region for the Distributed Coordination of Delayed Fractional-Order Multi-Agent Systems
Authors: Koochakzadeh Abbasali , Naderi Soorki Mojtaba , Azizi Aydin , Mohammadsharifi Kamran , Riazat Mohammadreza
Published: March 2023

Delay and especially delay in the transmission of agents’ information, is one of the most important causes of disruption to achieving consensus in a multi-agent system. This paper deals with achieving consensus in delayed fractional-order multi-agent systems (FOMAS). The aim in the present note is to find the exact maximum allowable delay in a FOMAS with non-uniform delay, i.e., the case in which the interactions between agents are subject to non-identical communication time-delays. By proving a stability theorem, the results available for non-delayed networked fractional-order systems are extended for the case in which interaction links have nonequal communication time-delays. In this extension by considering a time-delay coordination algorithm, necessary and sufficient conditions on the time delays and interaction graph are presented to guarantee the coordination. In addition, the delay-dependent stability region is also obtained. Finally, the dependency of the maximum allowable delay on two parameters, the agent fractional-order and the largest eigenvalue of the graph Laplacian matrix, is exactly determined. Numerical simulation results are given to confirm the proposed methodologies.
A Flexible Class of Two-Piece Normal Distribution with a Regression Illustration to Biaxial Fatigue Data
Authors: Salinas Hugo , Bakouch Hassan , Qarmalah Najla , Martínez-Flórez Guillermo
Published: March 2023

Using a two-piece normal distribution for modeling univariate data that exhibits symmetry, and uni/bimodality is notably effective. In this respect, the shape parameter value determines whether unimodality or bimodality is present. This paper proposes a flexible uni/bimodal distribution with platykurtic density, which can be used to simulate a variety of data. The concept is based on the transforming of a random variable into a folded distribution. Further, the proposed class includes the normal distribution as a sub-model. In the current study, the maximum likelihood method is considered for deriving the main structural properties and for the estimation of parameters. In addition, simulation experiments are presented to evaluate the behavior of estimators. Finally, fitting and regression applications are presented to illustrate the usefulness of the proposed distribution for data modeling in different real-life scenarios.
Pyrrole-Containing Alkaloids from a Marine-Derived Actinobacterium Streptomyces zhaozhouensis and Their Antimicrobial and Cytotoxic Activities
Authors: Heo Chang-Su , Kang Jong Soon , Kwon Joo-Hee , Anh Cao Van , Shin Hee Jae
Published: March 2023

Two new alkaloids, streptopyrroles B and C (1 and 2), were discovered through a chemical investigation of the ethyl acetate (EtOAc) extract from a marine-derived actinomycete, Streptomyces zhaozhouensis, along with four known analogs (3–6). The structures of the new compounds were elucidated by spectroscopic analysis (HR-ESIMS, 1D, and 2D NMR) and a comparison of their experimental data with literature values. The new compounds were evaluated for their antimicrobial activity by standard broth dilution assay, and the tested compounds showed significant activity against Gram-positive bacteria with minimum inhibitory concentration (MIC) values ranging from 0.7 to 2.9 µM, and kanamycin was used as a positive control with MIC values ranging from <0.5 to 4.1 µM. Additionally, 1, 3, and 5 were evaluated for their cytotoxicity against six tumor cell lines by sulforhodamine B (SRB) assay, and these compounds displayed cytotoxic activities against all the tested cell lines, with concentration causing 50% cell growth inhibition (GI50) values ranging from 4.9 to 10.8 µM, while a positive control, adriamycin, showed GI50 values of 0.13–0.17 µM.
A Pilot Experiment to Measure the Initial Mechanical Stability of the Femoral Head Implant in a Cadaveric Model of Osteonecrosis of Femoral Head Involving up to 50% of the Remaining Femoral Head
Authors: Woo Seungha , Lee Youngho , Sun Doohoon
Published: March 2023

Background and Objectives: Currently, only patients with osteonecrosis of the femoral head (ONFH), who had bone defects involving 30–33.3% of the remaining femoral head, are indicated in hip resurfacing arthroplasty (HRA). In an experimental cadaver model of ONFH involving up to 50% of the remaining femoral head, the initial stability of the femoral head implant (FHI) at the interface between the implant and the remaining femoral head was measured. Materials and Methods: The ten specimens and the remaining ten served as the experimental group and the control group, respectively. We examined the degree of the displacement of the FHI, the bonding strength between the FHI and the retained bone and that at the interface between the FHI and bone cement. Results: Changes in the degree of displacement at the final phase from the initial phase were calculated as 0.089 ± 0.036 mm in the experimental group and 0.083 ± 0.056 mm in the control group. However, this difference reached no statistical significance (p = 0.7789). Overall, there was an increase in the degree of displacement due to the loading stress, with increased loading cycles in both groups. In cycles of up to 6000 times, there was a steep increase. After cycles of 8000 times, however, there was a gradual increase. Moreover, in cycles of up to 8000 times, there was an increase in the difference in the degree of displacement due to the loading stress between the two groups. After cycles of 8000 times, however, such difference remained almost unchanged. Conclusions: In conclusion, orthopedic surgeons could consider performing the HRA in patients with ONFH where the bone defects involved up to 50% of the remaining femoral head, without involving the femoral head–neck junction in the anterior and superior area of the femoral head. However, more evidence-based studies are warranted to justify our results.
Cardiolipin Strongly Inhibits the Leakage Activity of the Short Antimicrobial Peptide ATRA-1 in Comparison to LL-37, in Model Membranes Mimicking the Lipid Composition of Staphylococcus aureus
Authors: Calderón-Rivera Nathalia , Múnera-Jaramillo Jessica , Jaramillo-Berrio Sara , Suesca Elizabeth , Manrique-Moreno Marcela , Leidy Chad
Published: March 2023

Cardiolipin is one of the main phospholipid components of Staphylococcus aureus membranes. This lipid is found at varying concentrations in the bilayer, depending on the growth stage of the bacteria, and as a response to environmental stress. Cardiolipin is an anionic phospholipid with four acyl chains, which modulates the bending properties of the membrane due to its inverted conical shape. It has been shown to inhibit the pore forming activity of several antimicrobial peptides, in general doubling the peptide concentration needed to induce leakage. Here we find that the short snake-derived antimicrobial peptide ATRA-1 is inhibited by several orders of magnitude in the presence of cardiolipin in saturated membranes (DMPG) compared to the human cathelicidin LL-37, which is only inhibited two-fold in its leakage-inducing concentration. The ATRA-1 is too short to span the membrane and its leakage activity is likely related to detergent-like alterations of bilayer structure. Fluorescence spectroscopy shows only a minor effect on ATRA-1 binding to DMPG membranes due to the presence of cardiolipin. However, FTIR spectroscopy shows that the acyl chain structure of DMPG membranes, containing cardiolipin, become more organized in the presence of ATRA-1, as reflected by an increase in the gel to liquid-crystalline phase transition temperature. Instead, a depression in the melting temperature is induced by ATRA-1 in DMPG in the absence of cardiolipin. In comparison, LL-37 induces a depression of the main phase transition of DMPG even in the presence of cardiolipin. These data suggest that cardiolipin inhibits the penetration of ATRA-1 into the membrane core, impeding its capacity to disrupt lipid packing.
Ultrasonic Cavitation Erosion Behavior of CoCrxFeMnNi High-Entropy Alloy Coatings Prepared by Plasma Cladding
Authors: Zhang Kaige , Yin Danqing , Wang Bin , Li Maochang , Xiao Xiao , Ma Ning , Zhang Keke
Published: March 2023

CoCrxFeMnNi (x represents the atomic percentage of Cr element, x = 20, 25, 30, and 35, denoted as Cr20, Cr25, Cr30, and Cr35 alloys) high-entropy alloy (HEA) coatings were cladded by plasma arc on the surface of 0Cr13Ni5Mo steel. The effects of Cr elements on the cavitation erosion mechanisms were studied by comparing the differences of microstructure, microhardness, cavitation erosion volume loss (CVL), cavitation erosion volume loss rate (CER), and eroded surface morphologies between the coatings. As the Cr content increased, the microhardness of the coatings increased continuously, and the microstructure transformed into fine dendrites. The microhardnesses of Cr20, Cr25, Cr30, and Cr35 were 223.9 HV, 250.5 HV, 265.2 HV, and 333.7 HV, respectively. With structural change, the slip pattern shifted from uniform distribution to distribution along the grain boundary, increasing slip resistance. Additionally, strain hardening capacity increased with reduced stacking fault energy (SFE). The resistance to cavitation erosion (CR) of the HEA increased with the increase in Cr content. The CVL of 20 h cavitation erosion of Cr35 coating was only 26.84% of that of 0Cr13Ni5Mo steel, and the peak CER was only 28.75% of that of 0Cr13Ni5Mo steel. The fracture damage mechanisms of the four HEA coatings were an obvious lamellar structure and fibrous fracture.
MoSe2 Complex with N and B Dual-Doped 3D Carbon Nanofibers for Sodium Batteries
Authors: Zhao Weigang , Liu Cuirong , Yin Xu
Published: March 2023

The sodium battery is one of the best energy storage technologies due to its abundant resource reserves and excellent energy storage ability. As a two-dimensional layered transition metal, molybdenum selenide (MoSe2) has large interlayer spacing and a high theoretical capacity (470 mAh∙g−1). Its structure is suitable for the negative electrode of sodium-ion batteries, with a large ionic radius and slow ion diffusion kinetics. However, it is difficult for the rate capability and cycling performance of MoSe2 to meet practical needs due to a weak intrinsic electron transport ability and volume expansion during sodium absorption. The hydrothermal synthesis method was used to synthesize the MoSe2 complex based on boron and nitrogen dual-doped 3D carbon fibers obtained from bacterial cellulose membranes (MoSe2/N&B-BCM) for sodium batteries. Additionally, electrochemical analysis and experimental characterization were performed. In summary, the experimental analysis shows that MoSe2/N&B-BCM has excellent conductivity, structural integrity, cyclability (328 mAh∙g−1 after 100 cycles at a 0.5 c constant rate), and rate stability.
Neurotransmitters in Type 2 Diabetes and the Control of Systemic and Central Energy Balance
Authors: Al-Sayyar Amnah , Hammad Maha M. , Williams Michayla R. , Al-Onaizi Mohammed , Abubaker Jehad , Alzaid Fawaz
Published: March 2023

Efficient signal transduction is important in maintaining the function of the nervous system across tissues. An intact neurotransmission process can regulate energy balance through proper communication between neurons and peripheral organs. This ensures that the right neural circuits are activated in the brain to modulate cellular energy homeostasis and systemic metabolic function. Alterations in neurotransmitters secretion can lead to imbalances in appetite, glucose metabolism, sleep, and thermogenesis. Dysregulation in dietary intake is also associated with disruption in neurotransmission and can trigger the onset of type 2 diabetes (T2D) and obesity. In this review, we highlight the various roles of neurotransmitters in regulating energy balance at the systemic level and in the central nervous system. We also address the link between neurotransmission imbalance and the development of T2D as well as perspectives across the fields of neuroscience and metabolism research.
Glycerol Droplet Spreading on Growing Bacillus Subtilis Biofilms
Authors: Luo Siyang , Liu Yanan , Luo Hao , Jing Guangyin
Published: March 2023

Bacterial biofilm is a three-dimensional matrix composed of a large number of living bacterial individuals. The strong bio-interaction between the bacteria and its self-secreted matrix environment strengthens the mechanical integrity of the biofilm and the sustainable resistance of bacteria to antibiotics. As a soft surface, the biofilm is expected to present different dynamical wetting behavior in response to shear stress, which is, however, less known. Here, the spreading of liquid droplet on Bacillus subtilis biofilm at its different growing phases was experimentally investigated. Due to the viscoelastic response of the biofilm to fast spreading of the droplet, three stages were identified as inertial, viscous stages, and a longer transition in between. The physical heterogeneity of growing biofilm correlates with the spreading scaling within the inertial stage, followed by the possible chemical variation after a critical growing time. By using the duration of inertial spreading, the characteristic time scale was successfully linked to the shear modulus of the elastic dissipation of the biofilm. This measurement suggests a facile, non-destructive and in vivo method to understand the mechanical instability of this living matter.
A RNase P Ribozyme Inhibits Gene Expression and Replication of Hepatitis B Virus in Cultured Cells
Authors: Yan Bin , Liu Yujun , Chen Yuan-Chuan , Liu Fenyong
Published: March 2023

Hepatitis B virus (HBV), an international public health concern, is a leading viral cause of liver disease, such as hepatocellular carcinoma. Sequence-specific ribozymes derived from ribonuclease P (RNase P) catalytic RNA are being explored for gene targeting applications. In this study, we engineered an active RNase P ribozyme, M1-S-A, targeting the overlapping region of HBV S mRNA, pre-S/L mRNA, and pregenomic RNA (pgRNA), all deemed essential for viral infection. Ribozyme M1-S-A cleaved the S mRNA sequence efficiently in vitro. We studied the effect of RNase P ribozyme on HBV gene expression and replication using the human hepatocyte HepG2.2.15 culture model that harbors an HBV genome and supports HBV replication. In these cultured cells, the expression of M1-S-A resulted in a reduction of more than 80% in both HBV RNA and protein levels and an inhibition of about 300-fold in the capsid-associated HBV DNA levels when compared to the cells that did not express any ribozymes. In control experiments, cells expressing an inactive control ribozyme displayed little impact on HBV RNA and protein levels, and on capsid-associated viral DNA levels. Our study signifies that RNase P ribozyme can suppress HBV gene expression and replication, implying the promise of RNase P ribozymes for anti-HBV therapy.
Pseudomonas aeruginosa and the Complement System: A Review of the Evasion Strategies
Authors: González-Alsina Alex , Mateu-Borrás Margalida , Doménech-Sánchez Antonio , Albertí Sebastián
Published: March 2023

The increasing emergence of multidrug resistant isolates of P. aeruginosa causes major problems in hospitals worldwide. This concern is particularly significant in bloodstream infections that progress rapidly, with a high number of deaths within the first hours and without time to select the most appropriate treatment. In fact, despite improvements in antimicrobial therapy and hospital care, P. aeruginosa bacteremia remains fatal in about 30% of cases. The complement system is a main defensive mechanism in blood against this pathogen. This system can mark bacteria for phagocytosis or directly lyse it via the insertion of a membrane attack complex in the bacterial membrane. P. aeruginosa exploits different strategies to resist complement attack. In this review for the special issue on “bacterial pathogens associated with bacteriemia”, we present an overview of the interactions between P. aeruginosa and the complement components and strategies used by this pathogen to prevent recognition and killing by the complement system. A thorough understanding of these interactions will be critical in order to develop drugs to counteract bacterial evasion mechanisms.
Oral Microbiota in Children and Adolescents with Type 1 Diabetes Mellitus: Novel Insights into the Pathogenesis of Dental and Periodontal Disease
Authors: Carelli Maria , Maguolo Alice , Zusi Chiara , Olivieri Francesca , Emiliani Federica , De Grandi Gelinda , Unali Ilaria , Zerman Nicoletta , Signoretto Caterina , Maffeis Claudio
Published: March 2023

The oral microbiota can be influenced by multiple factors, but only a few studies have focused on the role of glycemic control in determining early alterations of oral microbiota and their association with pathogenesis of both periodontitis and caries. The aim of this study is to evaluate the interplay between bacteria composition, oral hygiene, and glycemic control in a cohort of children with T1D. A total of 89 T1D children were enrolled (62% males, mean age: 12.6 ± 2.2 years). Physical and clinical characteristics, glucometabolic parameters, insulin treatment, and oral hygiene habits data were collected. Microbiological analysis was performed from saliva samples. A high prevalence of cariogenic and periodontopathogens bacteria in our cohort was detected. In particular, in all subjects Actinomyces spp., Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Lactobacillus spp. were isolated. S. mutans was found in about half of the analyzed sample (49.4%), in particular in patients with imbalance values of glycemic control. Moreover, a higher presence of both S. mutans and Veillonella spp. was detected in subjects with poorer glycemic control, in terms of HbA1c, %TIR and %TAR, even adjusting for age, sex, and hygiene habits as covariates. Virtuous oral hygiene habits, such as frequency of toothbrush changes and professional oral hygiene, negatively correlated with the simultaneous presence of Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis, red complex bacteria. Our study shows it is crucial to pay attention to glycemic control and regular oral hygiene to prevent the establishment of an oral microbiota predisposing to dental and periodontal pathology in subjects with T1D since childhood.
Re-Mining of Waste Rock Dumps from a Closed Lead–Zinc Mine—Characterisation of the Residuals
Authors: Maroušek Lukas , Dollinger Sabrina , Elmer Simone , Öfner Wolfgang , Nussbacher Hanspeter , Melcher Frank , Flachberger Helmut
Published: March 2023

The lead–zinc mine Bleiberg-Kreuth located in the Austrian federal state of Carinthia has had a long mining history, spanning from the early 14th century to the 1990s. The mining and processing activities undertaken over the centuries and, consequently, the composition of the waste rock material changed throughout this period. Today, the focus on waste rock dumps is motivated firstly by environmental interests and secondly by economic aspects. This article provides a comprehensive approach for the characterisation of three different waste rock dumps. The characterisation covers both mineralogical–geological methods and those involving the use of a mineral processor. The characterisation method presented herein starts with the sampling and calculation of the sampling mass, followed by sieve analysis and sink–float analysis, resulting in a two-dimensional fractional analysis. The consolidated results of the fractional and chemical analyses allow for a simplified forecast model for an ideal classification and density separation. Finally, the practical processability of a pre-concentration was tested by trials for comminution, classification, and density sorting.
A Comprehensive Review of Large Strain Consolidation Testing for Application in Oil Sands Mine Tailings
Authors: Ahmed Mahmoud , Beier Nicholas A. , Kaminsky Heather
Published: March 2023

Oil sand tailings are a mixture of sand, fines, water, and a residual amount of un-extracted bitumen in varying proportions. Tailings management is highly dependent on the consolidation behavior of the tailings. Although a great deal of work on this sector has been performed to study the consolidation behavior of oil sands tailings, it continues to play a critical role in quantifying the long-term geotechnical stability of tailings storage facilities. A review of large strain consolidation testing that exists, whether in the industry or in academia, has been compiled and presented in this manuscript to illustrate the advantages and drawbacks of measuring consolidation behavior of tailings using these tests. For oil sands mine tailings, it has been concluded that the conventional oedometer consolidation test can result in significant errors in quantifying the consolidation behavior. Conversely, testing procedures such as multi-step loading large strain consolidation tests, large slurry consolidometer tests, centrifuge testing, and seepage induced consolidation tests are widely employed to quantify the consolidation behavior of oil sands tailings.
Thermal Behaviors and Interaction Mechanism of Ammonium Dinitramide with Nitrocellulose
Authors: Wang Qiong , Wang Xiao-Hong , Pan Qing , Chang Hai , Yu Hong-Jian , Pang Wei-Qiang
Published: March 2023

The initial interaction mechanism is very important for the design and safety of nano-scale composite energetic materials composed of ammonium dinitramide (ADN) and nitrocellulose (NC). The thermal behaviors of ADN, NC and an NC/ADN mixture under different conditions were studied by using differential scanning calorimetry (DSC) with sealed crucibles, an accelerating rate calorimeter (ARC), a self-developed gas pressure measurement instrument and a DSC-thermogravimetry (TG)—quadrupole mass spectroscopy (MS)—Fourier transform infrared spectroscopy (FTIR) combined technique. The results show that the exothermic peak temperature of the NC/ADN mixture shifted forward greatly in both open and closed circumstances compared to those of NC or ADN. After 585.5 min under quasi-adiabatic conditions, the NC/ADN mixture stepped into the self-heating stage at 106.4 °C, which was much less than the initial temperatures of NC or ADN. The significant reduction in net pressure increment of NC, ADN and the NC/ADN mixture under vacuum indicates that ADN initiated the interaction of NC with ADN. Compared to gas products of NC or ADN, two new kinds of oxidative gases O2 and HNO2 appeared for the NC/ADN mixture, while NH3 and aldehyde disappeared. The mixing of NC with ADN did not change the initial decomposition pathway of either, but NC made ADN more inclined to decompose into N2O, which resulted in the formation of oxidative gases O2 and HNO2. The thermal decomposition of ADN dominated the initial thermal decomposition stage of the NC/ADN mixture, followed by the oxidation of NC and the cation of ADN.
Dissecting the Interactions between Chlorin e6 and Human Serum Albumin
Authors: Marconi Alessia , Mattioli Edoardo Jun , Ingargiola Filippo , Giugliano Giulia , Marforio Tainah Dorina , Prodi Luca , Di Giosia Matteo , Calvaresi Matteo
Published: March 2023

Chlorin e6 (Ce6) is among the most used sensitizers in photodynamic (PDT) and sonodynamic (SDT) therapy; its low solubility in water, however, hampers its clinical exploitation. Ce6 has a strong tendency to aggregate in physiological environments, reducing its performance as a photo/sono-sensitizer, as well as yielding poor pharmacokinetic and pharmacodynamic properties. The interaction of Ce6 with human serum albumin (HSA) (i) governs its biodistribution and (ii) can be used to improve its water solubility by encapsulation. Here, using ensemble docking and microsecond molecular dynamics simulations, we identified the two Ce6 binding pockets in HSA, i.e., the Sudlow I site and the heme binding pocket, providing an atomistic description of the binding. Comparing the photophysical and photosensitizing properties of Ce6@HSA with respect to the same properties regarding the free Ce6, it was observed that (i) a red-shift occurred in both the absorption and emission spectra, (ii) a maintaining of the fluorescence quantum yield and an increase of the excited state lifetime was detected, and (iii) a switch from the type II to the type I mechanism in a reactive oxygen species (ROS) production, upon irradiation, took place.
Computational Design, Synthesis, and Biophysical Evaluation of β-Amido Boronic Acids as SARS-CoV-2 Mpro Inhibitors
Authors: Fassi Enrico M. A. , Manenti Marco , Citarella Andrea , Dei Cas Michele , Casati Sara , Micale Nicola , Schirmeister Tanja , Roda Gabriella , Silvani Alessandra , Grazioso Giovanni
Published: March 2023

The COVID-19 pandemic has given a strong impetus to the search for antivirals active on SARS-associated coronaviruses. Over these years, numerous vaccines have been developed and many of these are effective and clinically available. Similarly, small molecules and monoclonal antibodies have also been approved by the FDA and EMA for the treatment of SARS-CoV-2 infection in patients who could develop the severe form of COVID-19. Among the available therapeutic tools, the small molecule nirmatrelvir was approved in 2021. It is a drug capable of binding to the Mpro protease, an enzyme encoded by the viral genome and essential for viral intracellular replication. In this work, by virtual screening of a focused library of β-amido boronic acids, we have designed and synthesized a focused library of compounds. All of them were biophysically tested by microscale thermophoresis, attaining encouraging results. Moreover, they also displayed Mpro protease inhibitory activity, as demonstrated by performing enzymatic assays. We are confident that this study will pave the way for the design of new drugs potentially useful for the treatment of SARS-CoV-2 viral infection.
Efficiency of Different Solvents in the Extraction of Bioactive Compounds from Plinia cauliflora and Syzygium cumini Fruits as Evaluated by Paper Spray Mass Spectrometry
Authors: Correia Vinícius Tadeu da Veiga , Silva Viviane Dias Medeiros , Mendonça Henrique de Oliveira Prata , Ramos Ana Luiza Coeli Cruz , Silva Mauro Ramalho , Augusti Rodinei , de Paula Ana Cardoso Clemente Filha Ferreira , Ferreira Ricardo Manuel de Seixas Boavida , Melo Júlio Onésio Ferreira , Fante Camila Argenta
Published: March 2023

Jabuticaba (Plinia cauliflora) and jambolan (Syzygium cumini) fruits are rich in phenolic compounds with antioxidant properties, mostly concentrated in the peel, pulp, and seeds. Among the techniques for identifying these constituents, paper spray mass spectrometry (PS-MS) stands out as a method of ambient ionization of samples for the direct analysis of raw materials. This study aimed to determine the chemical profiles of the peel, pulp, and seeds of jabuticaba and jambolan fruits, as well as to assess the efficiency of using different solvents (water and methanol) in obtaining metabolite fingerprints of different parts of the fruits. Overall, 63 compounds were tentatively identified in the aqueous and methanolic extracts of jabuticaba and jambolan, 28 being in the positive ionization mode and 35 in the negative ionization mode. Flavonoids (40%), followed by benzoic acid derivatives (13%), fatty acids (13%), carotenoids (6%), phenylpropanoids (6%), and tannins (5%) were the groups of substances found in greater numbers, producing different fingerprints according to the parts of the fruit and the different extracting solvents used. Therefore, compounds present in jabuticaba and jambolan reinforce the nutritional and bioactive potential attributed to these fruits, due to the potentially positive effects performed by these metabolites in human health and nutrition.
Development and Validation of a Rapid LC-MS/MS Method for Quantifying Alvocidib: In Silico and In Vitro Metabolic Stability Estimation in Human Liver Microsomes
Authors: Attwa Mohamed W. , AlRabiah Haitham , Kadi Adnan A.
Published: March 2023

Alvocidib (AVC; flavopiridol) is a potent cyclin-dependent kinase inhibitor used in patients with acute myeloid leukemia (AML). The FDA has approved orphan drug designation to AVC for treating patients with AML. In the current work, the in silico calculation of AVC metabolic lability was done using the P450 metabolism module of the StarDrop software package, that is expressed as a composite site lability (CSL). This was followed by establishing an LC-MS/MS analytical method for AVC estimation in human liver microsomes (HLMs) to assess metabolic stability. AVC and glasdegib (GSB), used as internal standards (IS), were separated utilizing a C18 column (reversed chromatography) with an isocratic mobile phase. The lower limit of quantification (LLOQ) was 5.0 ng/mL, revealing the sensitivity of the established LC-MS/MS analytical method that exhibited a linearity in the range 5–500 ng/mL in the HLMs matrix with correlation coefficient (R2 = 0.9995). The interday and intraday accuracy and precision of the established LC-MS/MS analytical method were −1.4% to 6.7% and −0.8% to 6.4%, respectively, confirming the reproducibility of the LC-MS/MS analytical method. The calculated metabolic stability parameters were intrinsic clearance (CLint) and in vitro half-life (t1/2) of AVC at 26.9 µL/min/mg and 25.8 min, respectively. The in silico results from the P450 metabolism model matched the results generated from in vitro metabolic incubations; therefore, the in silico software can be used to predict the metabolic stability of the drugs, saving time and resources. AVC exhibits a moderate extraction ratio, indicating reasonable in vivo bioavailability. The established chromatographic methodology was the first LC-MS/MS method designed for AVC estimation in HLMs matrix that was applied for AVC metabolic stability estimation.
Total Synthesis of Lineaflavones A, C, D, and Analogues
Authors: Wang Rui , Fu Yu , Ma Ran , Jin Hongzhen , Zhao Wei
Published: March 2023

The first total synthesis of lineaflavones A, C, D, and their analogues has been accomplished. The key synthetic steps include aldol/oxa-Michael/dehydration sequence reactions to assemble the tricyclic core, Claisen rearrangement and Schenck ene reaction to construct the key intermediate, and selective substitution or elimination of tertiary allylic alcohol to obtain natural compounds. In addition, we also explored five new routes to synthesize fifty-three natural product analogues, which can contribute to a systematic structure–activity relationship during biological evaluation.
Preparation and Surface Characterization of Chitosan-Based Coatings for PET Materials
Authors: Szafran Klaudia , Jurak Małgorzata , Mroczka Robert , Wiącek Agnieszka Ewa
Published: March 2023

Poly(ethylene terephthalate)—PET—is one of the most frequently used polymers in biomedical applications. Due to chemical inertness, PET surface modification is necessary to gain specific properties, making the polymer biocompatible. The aim of this paper is to characterize the multi-component films containing chitosan (Ch), phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), immunosuppressant cyclosporine A (CsA) and/or antioxidant lauryl gallate (LG) which can be utilized as a very attractive material for developing the PET coatings. Chitosan was employed owing to its antibacterial activity and also its ability to promote cell adhesion and proliferation favorable for tissue engineering and regeneration purposes. Moreover, the Ch film can be additionally modified with other substances of biological importance (DOPC, CsA and LG). The layers of varying compositions were prepared using the Langmuir—Blodgett (LB) technique on the air plasma-activated PET support. Then their nanostructure, molecular distribution, surface chemistry and wettability were determined by atomic force microscopy (AFM), time-of-flight secondary ion mass spectrometry (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), contact angle (CA) measurements and the surface free energy and its components’ determination, respectively. The obtained results show clearly the dependence of the surface properties of the films on the molar ratio of components and allow for a better understanding of the coating organization and mechanisms of interactions at the molecular level both inside the films and between the films and the polar/apolar liquids imitating the environment of different properties. The organized layers of this type can be helpful in gaining control over the surface properties of the biomaterial, thus getting rid of the limitations in favor of increased biocompatibility. This is a good basis for further investigations on the correlation of the immune system response to the presence of biomaterial and its physicochemical properties.
Different Types of Hypericum perforatum cvs. (Elixir, Helos, Topas) In Vitro Cultures: A Rich Source of Bioactive Metabolites and Biological Activities of Biomass Extracts
Authors: Kwiecień Inga , Miceli Natalizia , Kędzia Elżbieta , Cavò Emilia , Taviano Maria Fernanda , Beerhues Ludger , Ekiert Halina
Published: March 2023

Microshoot agitated and bioreactor cultures (PlantForm bioreactors) of three Hypericum perforatum cultivars (Elixir, Helos, Topas) were maintained in four variants of Murashige and Skoog medium (MS) supplemented with 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA) (in the range of 0.1–3.0 mg/L). In both types of in vitro cultures, the accumulation dynamics of phenolic acids, flavonoids, and catechins were investigated during 5- and 4-week growth cycles, respectively. The contents of metabolites in methanolic extracts from biomasses collected in 1-week intervals were estimated by HPLC. The highest total contents of phenolic acids, flavonoids, and catechins were 505, 2386, and 712 mg/100 g DW, respectively (agitated cultures of cv. Helos). The extracts from biomass grown under the best in vitro culture conditions were examined for antioxidant and antimicrobial activities. The extracts showed high or moderate antioxidant activity (DPPH, reducing power, and chelating activity assays), high activity against Gram-positive bacteria, and strong antifungal activity. Additionally, experiments with phenylalanine feeding (1 g/L) in agitated cultures were performed reaching the highest enhancement of the total contents of flavonoids, phenolic acids, and catechins on day 7 after the addition of the biogenetic precursor (2.33-, 1.73- and 1.33-fold, respectively). After feeding, the highest accumulation of polyphenols was detected in the agitated culture of cv. Elixir (4.48 g/100 g DW). The high contents of metabolites and the promising biological properties of the biomass extracts are interesting from a practical point of view.
Study on Absorption, Distribution and Excretion of a New Candidate Compound XYY-CP1106 against Alzheimer’s Disease in Rats by LC-MS/MS
Authors: Guo Zili , Gao Bianbian , Fan Miaoliang , Chen Lisha , Zhang Changjun , Liang Xianrui , Su Weike , Xie Yuanyuan
Published: March 2023

XYY-CP1106, a candidate compound synthesized from a hybrid of hydroxypyridinone and coumarin, has been shown to be remarkably effective in treating Alzheimer’s disease. A simple, rapid and accurate high-performance liquid chromatography coupled with the triple quadrupole mass spectrometer (LC-MS/MS) method was established in this study to elucidate the pharmacokinetics of XYY-CP1106 after oral and intravenous administration in rats. XYY-CP1106 was shown to be rapidly absorbed into the blood (Tmax, 0.57–0.93 h) and then eliminated slowly (T1/2, 8.26–10.06 h). Oral bioavailability of XYY-CP1106 was (10.70 ± 1.72)%. XYY-CP1106 could pass through the blood–brain barrier with a high content of (500.52 ± 260.12) ng/g at 2 h in brain tissue. The excretion results showed that XYY-CP1106 was mainly excreted through feces, with an average total excretion rate of (31.14 ± 0.05)% in 72 h. In conclusion, the absorption, distribution and excretion of XYY-CP1106 in rats provided a theoretical basis for subsequent preclinical studies.