bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vitro Antibacterial and Wound Healing Activities Evoked by Silver Nanoparticles Synthesized through Probiotic Bacteria
Authors: Vijayakumar Gayathri , Kim Hyung Joo , Rangarajulu Senthil Kumaran
Published: January 2023

The prospective application of probiotics is an adjuvant for the advancement of novel antimicrobial and wound-healing agents. Currently, probiotic bacteria are utilized for the biosynthesis of nanoparticles in the development of innovative therapeutics. The present study aimed at using nanoparticle-conjugated probiotic bacteria for enhanced antibacterial and wound-healing activity. In the present investigation, the probiotic bacteria were isolated from a dairy source (milk from domestic herbivores). They screened for antibacterial activity against infection-causing Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Bacillus subtilis and Staphylococcus aureus) pathogens. Further, the probiotic strain with higher bactericidal activity was used to synthesize silver, selenium, and copper nanoparticles. The isolated strain was found to be Lactiplantibacillus plantarum and it only has the ability to synthesize silver nanoparticles. This was verified using Ultra violet-Visible (UV-Vis) spectroscopy, where the test solution turned brown and the greatest UV-Vis absorptions peaked at 425 nm. Optimization studies on the synthesis of AgNPs (silver nanoparticles) are presented and the results show that stable synthesis was obtained by using a concentration of 1mM silver nitrate (AgNO3) at a temperature of 37 °C with pH 8. The FTIR (Fourier transform infrared spectroscopy) study confirmed the involvement of functional groups from the cell biomass that were involved in the reduction process. Additionally, biosynthesized AgNPs showed increased antioxidant and antibacterial activities. The nano silver had a size distribution of 14 nm and was recorded with HR-TEM (high-resolution transmission electron microscopy) examination. The EDX (energy dispersive X-ray) analysis revealed 57% of silver groups found in the nanoparticle production. The biosynthesized AgNPs show significant wound-healing capabilities with 96% of wound closure (fibroblast cells) being observed through an in vitro scratch-wound assay. The cytotoxic experiments demonstrated that the biosynthesized AgNPs are not extremely hazardous to the fibroblast cells. The present study provides a new platform for the green synthesis of AgNPs using probiotic bacteria, showing significant antibacterial and wound-healing potentials against infectious pathogens.
Protopanaxadiol-Enriched Rice Extracts Suppressed Oxidative and Melanogenic Activities in Melan-a Cells
Authors: Monmai Chaiwat , Kim Jin-Suk , Promyot Karantharat , Baek So-Hyeon
Published: January 2023

Concerns about hyperpigmentation and skin appearance have led to increasing research into the prevention and altering of skin pigmentation. Natural compounds may be of interest in the search for skin-lightening actives. Protopanaxadiol (PPD), a gut microbiome-induced ginseng metabolite, has been reported to have anti-melanogenic effects. This study aimed to evaluate the antioxidative and anti-melanogenic effects of PPD-enriched rice seed extracts on melan-a cells. The antioxidant and cytotoxicity activities of the extracts were investigated in melan-a cells before measuring their responses to melanogenic activities. The extracts significantly enhanced the antioxidant potency compared with normal rice seed extract. PPD-enriched rice seed extracts (i) significantly downregulated microphthalmia-associated transcription factor, which led to a reduction in tyrosinase and tyrosinase-related protein-1 and -2, (ii) decrease in the cellular tyrosinase activity and melanin content, (iii) reduction in the number of melanin-containing cells, (iv) promotion of melanogenesis downregulators, phosphorylation of extracellular signal-regulated kinase 1/2 and protein kinase B, and (v) downregulation of the phosphorylated p38 mitogen-activated protein kinase and melanin synthesis. These results indicate the feasibility of PPD-enriched rice seed extracts as a novel agent for suppressing melanogenesis and controlling hyperpigmentation.
Engineered Adipose-Derived Stem Cells Overexpressing RXFP1 via CRISPR Activation Ameliorate Erectile Dysfunction in Diabetic Rats
Authors: Sun Taotao , Xu Wenchao , Tu Bocheng , Wang Tao , Liu Jihong , Liu Kang , Luan Yang
Published: January 2023

Due to the high incidence of diabetes mellitus (DM) and poor response to the first-line treatment of DM-induced erectile dysfunction (DMED), new therapeutic strategies for DMED are needed. Adipose-derived stem cell (ADSC) transplantation is considered a promising treatment modality for DMED but is limited by poor survival and efficacy after transplantation. In this study, we aimed to increase the therapeutic effect of DMED by overexpressing the relaxin family peptide receptor 1 (RXFP1) using a clustered regularly interspaced short palindromic repeats activation (CRISPRa) system in ADSCs. Two lentiviruses carrying the CRISPRa system transfected ADSCs to overexpress RXFP1 (RXFP1-ADSCs). The intracavernous injection of ADSCs was performed in DMED rats induced by the intraperitoneal injection of streptozotocin. Four weeks after transplantation, we measured erectile function and collected specimens of the corpus cavernosum for follow-up detection. The results showed that ADSCs improved erectile function in diabetic rats, and the RXFP1-ADSCs were more significant. We detected reduced levels of oxidative stress, apoptosis and fibrosis together with relative normalization of endothelial and smooth muscle cell function in the penis after ADSC transplantation. RXFP1-ADSCs had more potent efficacy in the above alterations compared to negative control ADSCs due to the high levels of survival and paracrine capacity in RXFP1-ADSCs. The results revealed that RXFP1-ADSC transplantation could partially preserve erectile function in DMED rats associated with the regulation of oxidative stress, apoptosis, fibrosis and endothelial and smooth muscle cell dysfunction. RXFP1 may be the new target for the genetic modification of ADSCs, which benefits the management of DMED.
The Relationship between Gait Velocity and Walking Pattern in Hemiplegic Patients
Authors: Nesi Barbara , Taviani Antonio , D’Auria Lucia , Bardelli Roberta , Zuccarello Giuseppe , Platano Daniela , Benedetti Maria Grazia , Benvenuti Francesco
Published: January 2023

Background Gait speed represents a functional predictor and an impairment severity index in stroke survivors; gait analysis parameters are descriptors of walking strategies used to compensate for the muscle impairment such as vaulting, circumduction and hip hiking. The aim of this study was to assess if there is a relationship between the gait compensatory strategy and gait speed of progression. Methods A sample of 30 patients with post-stroke hemiparesis was assessed for gait compensatory patterns through gait analysis and videorecording. BMI, pain-VAS, Barthel Index, Nottingham Extended ADL Scale, Motricity Index, lower limb muscles strength and aROMs were also included in the assessment. Results In 19 patients it was possible to identify one or more compensatory strategies; in 11 patients no specific gait pattern was found. The vaulting and hip hiking combined gait strategy had an effect on gait speed. Gait speed was directly related to Barthel Index, Nottingham Extended ADL Scale, Motricity Index of the paretic side and in particular with quadriceps and iliopsoas strength and hip extension aROM. Gender, age and paretic side did not influence gait speed. Conclusion Compensatory gait strategies influence gait speed but studies with larger sample size are needed to better highlight their impact.
Experimental Study on Engineering Properties of Cemented Soil with High Water Content
Authors: Yu Jianlin , Mao Zihao , Zhou Jiajin , Yu Zhongxiang , Liu Xiangwu , Gong Xiaonan
Published: January 2023

A series of unconsolidated-undrained triaxial tests and unconfined compressive strength (UCS) tests for cemented soils with different curing times were carried out in this research. In total, three cemented soil mixtures with different cement contents were adopted in the tests, and the confining pressure was controlled in the range of 100–1600 kPa. The influence of curing time, cemented soil mixture ratio and confining pressure on the compressive and shear capacity of cemented soil was analyzed based on the test results. The test results indicate that the cement content and curing time both had a great influence on the strength of cemented soil, the UCS of the cemented soil increased linearly with the curing time under the semi-logarithmic coordinate, the cemented soil exhibited strain softening characteristics in the axial shear tests, and the maximum deviatoric stress of the cemented soil increased with the increase in confining pressure. A linear correlation was found between the cohesion and the UCS of cemented soil, and the cohesion was about 0.40 times the compressive strength.
Parameter Optimization and Tuning Methodology for a Scalable E-Bus Fleet Simulation Framework: Verification Using Real-World Data from Case Studies
Authors: Hasan Mohammed Mahedi , Avramis Nikos , Ranta Mikaela , El Baghdadi Mohamed , Hegazy Omar
Published: January 2023

This study presents the optimization and tuning of a simulation framework to improve its simulation accuracy while evaluating the energy utilization of electric buses under various mission scenarios. The simulation framework was developed using the low fidelity (Lo-Fi) model of the forward-facing electric bus (e-bus) powertrain to achieve the fast simulation speeds necessary for real-time fleet simulations. The measurement data required to verify the proper tuning of the simulation framework is provided by the bus original equipment manufacturers (OEMs) and taken from the various demonstrations of 12 m and 18 m buses in the cities of Barcelona, Gothenburg, and Osnabruck. We investigate the different methodologies applied for the tuning process, including empirical and optimization. In the empirical methodology, the standard driving cycles that have been used in previous studies to simulate various use case (UC) scenarios are replaced with actual driving cycles derived from measurement data from buses traversing their respective routes. The key outputs, including the energy requirements, total cost of ownership (TCO), and impact on the grid are statistically compared. In the optimization scenario, the assumptions for the various vehicle and mission parameters are tuned to increase the correlation between the simulation and measurement outputs (the battery SoC profile), for the given scenario input (the velocity profile). Improved simple optimization (iSOPT) was used to provide a superfast optimization process to tune the passenger load in the bus, cabin setpoint temperature, battery’s age as relative capacity degradation (RCD), SoC cutoff point between constant current (CC) and constant voltage charging (CV), charge decay factor used in CV charging, charging power, and cutoff in initial velocity during braking for which regenerative braking is activated.
Variation of Acoustic Transmission Spectrum during the Muscle Fatigue Process
Authors: Li Pan , Yin Guanjun , Nie Shibo , Guo Jianzhong
Published: January 2023

The timely assessment of muscle fatigue makes sense for reducing the risk of musculoskeletal injury during exercise. In general, muscle fatigue is accompanied by physiological changes. These changes affect the acoustic transmission properties of the skeletal muscles. This study investigated the variation of the acoustic transmission spectrum (ATS) of human upper arm muscles during sustained static contractions (SC). Based on the B-ultrasound image and radiofrequency (RF) ultrasonic echoes, we abstracted the RF echo signals from the subcutaneous fatty/fascia (SFF) and deep fascia/bone (DFB) interfaces. By dividing the echo spectrum of the DFB by the spectrum of the SFF, we obtained the ATS of the upper arm muscles. Then, by fitting the ATS with both the linear function (A(f) = af + b) and power-law function (A(f) = αƒβ), we analyzed the variations of a, b, α, and β along with the SC process of skeletal muscle. As muscle fatigue increases, the slope a decreases and the intercept b increases linearly; the α increases exponentially and β decreases linearly. In addition, the variation magnitude of ATS relates to the maximum voluntary contraction (MVC) force and the strength of the SC motion. These results suggest that a comprehensive analysis of ATS is a potential metric for assessing muscle fatigue.
Study on the Disturbance of Existing Subway Tunnels by Foundation Sloping Excavation
Authors: Fu He-Lin , Deng Huang-Shi , Zhao Yi-Bo , Chang Xiao-Bing , Yi Hai-Dong
Published: January 2023

Urban subway tunnels are located in a very complex operating environment, and the surrounding construction disturbances can lead to the deformation of existing tunnels or even produce tunnel disease issues. The disturbance of adjacent tunnels by pit excavation is an important geotechnical issue among scholars. In our study, the two-stage method is used to derive the deformation of the existing tunnel caused by the use of sloping excavation in the foundation pit. Subsequently, the correctness of the theoretical calculation formulae and the results are verified by constructing numerical calculation models. The effects of different slope footings θ, different slope widths b and different excavation depths H on the deformation of the existing tunnel are analyzed. The results show that: the excavation of the foundation pit can effectively reduce the tunnel deformation by using the sloping excavation method. The soil directly above the tunnel is the main factor causing the deformation of that tunnel. When the foundation pit spans a single-lane existing tunnel, the sloping excavation method of excavating soil on both sides and reserving the middle core soil can be used. When the foundation pit spans a double-lane existing tunnel, the sloping excavation method of excavating the middle soil and reserving core soil on both sides can be adopted. The error between the theoretical calculation results and the numerical simulation results is small, which verifies the correctness of the theoretical calculation results. The load distribution width of the soil after sloping excavation can be taken as the median line width. The deformation of the existing tunnel is influenced, to a greater extent, by changes in the one-time excavation depth H and slope width b, and to a lesser extent, by changes in the slope angle θ.
Thermodynamics of Chemical Hydrogen Storage: Are Sterically Hindered and Overcrowded Molecules More Effective?
Authors: Verevkin Sergey P. , Samarov Artemiy A. , Turovtsev Vladimir V. , Vostrikov Sergey V. , Wasserscheid Peter , Müller Karsten
Published: January 2023

Homocyclic aromatics with different degrees of alkylation have been investigated so far as Liquid Organic Hydrogen Carriers (LOHC). A low enthalpy of reaction for the dehydrogenation reaction is generally considered beneficial. Values available for crowded, multi-alkylated aromatics, such as hexamethyl benzene, indicate that these substances could be utilized efficiently as LOHCs. However, no clear trend can be identified in the existing data. The aim of this study is to provide a consistent and comprehensive data set on this substance class to evaluate if multi-alkylation is indeed beneficial. For this purpose, own and literature results from experimental methods such as combustion calorimetry and the transpiration method for measuring the enthalpy of vaporisation were combined with quantum chemical approaches to obtain a validated, consistent data set. This comprehensive study reveals that the positive effect on enthalpy of reaction for dehydrogenation is comparatively weak. A slightly lower enthalpy of reaction is actually observed for crowded alkylbenzenes, but it is most likely not sufficient to reach a significant decrease in temperature for hydrogen release. Nevertheless, the results are of high importance for the further development of LOHC systems with optimal structural motifs.
Study of the Mechanical Properties and Thermal Control Performance of Plasma-Sprayed Alumina Coating on Aluminum Alloy Surface
Authors: He Gengchao , Guo Weiling , He Dongyu , Zhang Jiaqiang , Xing Zhiguo , Lv Zhenlin , Jia Lei , Huang Yanfei
Published: January 2023

Thermal control coating is an important means of ensuring that a spacecraft remains operational at high temperatures. Due to limitations regarding preparation technology and material properties, the mechanical properties of the conventional thermal control coatings still need to be improved. To solve this problem, nanostructured alumina coatings (NCs) and conventional alumina coatings (CCs) were prepared using plasma-spraying technology. The microscopic morphology, phase structure, hardness, and thermal control properties (solar absorptance (αs) and emissivity (ε)) of the nanostructured alumina coatings were investigated and compared with those of conventional alumina coatings. The results show that the NC has a higher hardness value (1168.8 HV) and that its reflectivity exceeds 75% in the wavelength range of 446–1586 nm, while a high degree of emissivity of 0.863–0.87 is still maintained at 300–393 K. Furthermore, the results show that these highly reflective properties are related to the phase composition and internal micromorphology of the NC, whereby the solar absorption of the coating is reduced due to the increase in the alpha phase content (21.4%), the high porosity (5.21%) and the nanoparticles favoring the internal scattering. All these properties can improve the performance of this CC coating with low solar absorptance (αs) and high emissivity (ε).
Method of Assessing the Logistics Process as Regards Information Flow Unreliability on the Example of a Container Terminal
Authors: Zając Mateusz , Swieboda Justyna
Published: January 2023

The reliability of logistics processes is most often considered in the context of the correct flow of materials. The information that accompanies the logistic flow is usually not considered a potential source of errors or disruptions to the correct operation of the logistic chain. The article presents literature studies in this field and presents a model for evaluating the logistics process, taking into account the quality of information. An example of process evaluation based on a container terminal was presented.
Image-Based Structural Health Monitoring: A Systematic Review
Authors: Payawal John Mark Go , Kim Dong-Keon
Published: January 2023

The early discovery of factors that compromise a civil infrastructure’s structural integrity allows for safety monitoring, timely prevention, and a prompt remedy to the discovered problem. As a result, researchers have been researching various methodologies and types of structural health monitoring (SHM). A systematic search was performed following the updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020) in Scopus and ScienceDirect from Elsevier, Google Scholar, MDPI, Springer, Wiley Online and ASCE Library, EOP and IOP Science, IEEE, and other databases with the reliable peer review process. From 1480 identified pieces of literature, one hundred and nine (109) sources met the criteria for inclusion and exclusion and were used to produce our findings. This study presents the identified purpose and application of image-based SHM, which includes: (1) identifying and discovering; (2) measuring and monitoring; (3) automating and increasing efficiency; and (4) promoting development and creating 3D models. Furthermore, the responsibilities and relevance of components and parameters for implementing image-based SHM devices and systems, and their issues, are covered in this paper. Future research can benefit from the stated applications for innovation and the requirements of image-based SHM.
Numerical Assessment of Interacting Structural Units on the Seismic Damage: A Comparative Analysis with Different Modeling Approaches
Authors: Schiavoni Mattia , Giordano Ersilia , Roscini Francesca , Clementi Francesco
Published: January 2023

The conservation of the historical and artistic heritage is one of the main priorities of Italian and international policy. The great variety of masonry buildings that make up this heritage is characterized by different combinations of materials and construction techniques. Then, several damage scenarios could be observed as a result, requiring appropriate retrofitting interventions. A rather accurate structural behavior analysis, especially for horizontal load conditions, allows for elaborating a correct seismic assessment. Albeit there are various numerical tools available to examine them, each one’s process starts by means of certain assumptions that could not be applied indiscriminately. This paper aims to compare two different types of modeling techniques to evaluate their strengths and weaknesses. To achieve this goal, an earthquake-damaged complex in Central Italy was chosen as a case study. The structure was modeled using a finite element (continuous) and a distinct element (discontinuous) method. Both approaches underwent a nonlinear dynamic analysis using the strong motions recorded during the 2016 seismic sequence. The results show that both approaches can evaluate the weak structural points. However, in some cases, the distinct element method appeared more accurate in reproducing the cracks.
Frequency Range Optimization for Continuous Wave Terahertz Imaging
Authors: Pongrac Blaž , Sarjaš Andrej , Gleich Dušan
Published: January 2023

With shorter wavelengths than microwaves and greater penetration depth than infrared light, waves in the terahertz spectrum offer unique material testing opportunities. Terahertz technology offers non-invasive and non-destructive testing in the form of spectroscopy and imaging. The most used systems for terahertz imaging are time-domain spectroscopy systems. However, frequency domain spectroscopy systems could offer excellent frequency resolution and be more suitable for biomedical applications. Terahertz imaging based on frequency domain spectroscopy systems is slow, and suffers from frequency tuning errors. A novel one-dimensional imaging principle is presented in this paper. In addition, frequency range optimization based on convolutional neural networks and occlusion sensitivity is utilized for frequency range optimization. Frequency range optimization is used to determine the optimal frequency range for data acquisition. The optimal frequency range or bandwidth should be wide enough for effective phase detection, and should be at the intersection of several spectral footprints in the observed medium. The intersection of spectral footprints is estimated using the proposed frequency range optimization algorithm based on a convolutional neural network and occlusion sensitivity algorithm. The proposed algorithm selects the most sensitive frequency band of THz spectrum automatically, and enables very fast acquisitions for object inspection and classification.
A Combined Artificial-Intelligence Aerodynamic Design Method for a Transonic Compressor Rotor Based on Reinforcement Learning and Genetic Algorithm
Authors: Xu Xiaohan , Huang Xudong , Bi Dianfang , Zhou Ming
Published: January 2023

An aircraft engine’s performance depends largely on the compressors’ aerodynamic design, which aims to achieve higher stage pressure, efficiency, and an acceptable stall margin. Existing design methods require substantial prior knowledge and different optimization algorithms to determine the 2D and 3D features of the blades, in which the design policy needs to be more readily systematized. With the development of artificial intelligence (AI), deep reinforcement learning (RL) has been successfully applied to complex design problems in different domains and provides a feasible method for compressor design. In addition, the applications of AI methods in compressor research have progressively developed. This paper described a combined artificial-intelligence aerodynamic design method based on a modified deep deterministic policy gradient algorithm and a genetic algorithm (GA) and integrated the GA into the RL framework. The trained agent learned the design policy and used it to improve the GA optimization result of a single-stage transonic compressor rotor. Consequently, the rotor exhibited a higher pressure ratio and efficiency owing to the sweep feature, lean feature, and 2D airfoil angle changes. The separation near the tip and the secondary flow decreased after the GA process, and at the same time, the shockwave was weakened, providing improved efficiency. Most of these beneficial flow field features remained after agent modification to improve the pressure ratio, showing that the policy learned by the agent was generally universal. The combination of RL and other design optimization methods is expected to benefit the future development of compressor designs by merging the advantages of different methods.
Integrity and Privacy-Aware, Patient-Centric Health Record Access Control Framework Using a Blockchain
Authors: Abutaleb Rayan Anwar , Alqahtany Saad Said , Syed Toqeer Ali
Published: January 2023

Blockchains are gaining traction as secure and reliable platforms for data sharing in fields such as banking, supply chain management, food production, energy, the Internet, and medical services. Furthermore, when decentralized, a blockchain can be regarded as an immutable ledger storing data entries. Moreover, this modern technology was designed to disrupt various data-driven industries, including the healthcare industry. While electronic healthcare services have enabled more straightforward and accessible treatment, patient privacy has become vulnerable to external and internal attacks by healthcare personnel. Therefore, we aimed to design a framework to control patient health records that ensures the patient can provide the necessary permissions to those who access his/her health records. This framework will record all activities via blockchain and usage control. Through this framework, we aim to create a user-centric and privacy-aware experience. A literature review and experiments have been performed to select an optimized and placable blockchain operating system. In addition, performance analysis showed that the OS and smart contracts work at an acceptable speed.
Longitudinal Variation of Thermospheric Density during Low Solar Activity from APOD Observations
Authors: Chen Guangming , Li Xie , He Maosheng , Liu Shushi , Man Haijun , Gao Hong , Li Yongping
Published: January 2023

The longitudinal distribution of upper atmospheric density has been broadly studied. However, the studies mostly focused on 24 h averaged distribution. This study presents the longitudinal distribution of thermospheric density at dawn and dusk, using observations collected by the atmospheric density detector onboard the Chinese satellite APOD (Atmospheric Density Detection and Precise Orbit Determination) during low solar activity. The APOD observations show a significant relative longitudinal variation of thermospheric density with global maxima (Δρrmax) near the geomagnetic pole, especially in the winter hemisphere. The annual maximum of Δρrmax appears in the Southern Hemisphere around the June solstices and reaches 26.3% and 39.6% at dawn and dusk, respectively. The auroral heating and meridional wind might play a significant role in the longitudinal variation of thermospheric density. We further compare the APOD observations with the semi-empirical atmospheric model MSIS (Mass Spectrometer Incoherent Scatter Radar) 2.0 predictions under low solar activity conditions. The MSIS 2.0 model reproduces similar longitudinal variations to the observations, with hemispheric asymmetry. The longitudinal variation of thermospheric density from APOD should be related to the distribution of the atmospheric average molecular weight from the model. More observational data are needed to verify the results of this study further.
A Neural-Network Based MPAS—Shallow Water Model and Its 4D-Var Data Assimilation System
Authors: Tian Xiaoxu , Conibear Luke , Steward Jeffrey
Published: January 2023

The technique of machine learning has been increasingly applied in numerical weather predictions. The aim of this study is to explore the application of a neural network in data assimilation by making use of the convenience in obtaining the tangent linear and adjoint (TL/AD) of a neural network (NN) and formulating a NN-based four-dimensional variational (4D-Var) DA system. A NN-based shallow water (SW) model is developed in this study. The NN model consists of three layers. The weights and biases in the NN-based SW model are trained with 60 years of hourly ERA5 geopotentials and wind field at 500 hPa as initial conditions and the corresponding 12-h forecasts by Model for Prediction Across Scales (MPAS)-SW, in total of 534,697 sets of samples. The 12-h forecasts from independent dates made by NN-based SW prove to closely emulate the simulations by the actual MPAS-SW model. This study further shows that the TL/AD of an NN model can be easily developed and validated. The ease of obtaining the TL/AD makes NN conveniently applicable in various aspects within a data assimilation (DA) system. To demonstrate such, a continuous 4D-Var DA system is also developed with the forward NN and its adjoint. To demonstrate the functionality of the NN-based 4D-Var DA system, the results from a higher resolution simulation will be treated as observations and assimilated to analyze the low resolution initial conditions. The forecasts starting from the analyzed initial conditions will be compared with those without assimilation to demonstrate improvements.
Performance Analysis of a Portable Low-Cost SDR-Based Ionosonde
Authors: Koloskov Oleksandr , Kashcheyev Anton , Bogomaz Oleksandr , Sopin Andriy , Gavrylyuk Bogdan , Zalizovski Andriy
Published: January 2023

This work presents a software-defined radio ionosonde (ISDR) developed at the Abdus Salam International Centre for Theoretical Physics (Italy) and the Institute of Radio Astronomy (Ukraine) and installed at the Ukrainian Antarctic Station in 2017. For the first time, the results of the long-term data comparison of the ISDR with the conventional ionosonde IPS-42 produced by KEL Aerospace are presented and discussed. The matching of the ionograms obtained during the whole year of 2021, as well as a comparison of the critical frequencies and virtual heights of F, E, and Es layers manually scaled from the ionograms showed that the ISDR has a similar level of performance to IPS-42. At the same time, the ISDR is a more versatile instrument that supports a bistatic operation, provides Doppler measurements and polarization information, and has a significantly lower cost and transmission power. Different configurations of the ISDR are considered. The basic configuration allows for using the ISDR as a conventional vertical ionospheric sounder. An enhanced configuration of the ISDR allows for oblique sounding, as well as polarization information that enables the O- and X-propagation modes of the ionospheric signal to be distinguished. The enhanced passive version of the ISDR was successfully tested onboard the research vessel “Noosfera” on distances up to 1,400 km from the transmitting ISDR.
Functional Epistemology “Nullifies” Dyson’s Rebuttal of Perturbation Theory
Authors: Svozil Karl
Published: January 2023

Functional epistemology is about ways to access functional objects by using varieties of methods and procedures. Not all such means are equally capable of reproducing these functions in the desired consistency and resolution. Dyson’s argument against the perturbative expansion of quantum field theoretic terms, in a radical form (never pursued by Dyson), is an example of epistemology taken as ontology.
Dynamic Behavior of a Predator–Prey Model with Double Delays and Beddington–DeAngelis Functional Response
Authors: Cui Minjuan , Shao Yuanfu , Xue Renxiu , Zhao Jinxing
Published: January 2023

In the predator–prey system, predators can affect the prey population by direct killing and predation fear. In the present study, we consider a delayed predator–prey model with fear and Beddington–DeAngelis functional response. The model incorporates not only the fear of predator on prey with an intraspecific competition relationship, but also fear delay and pregnancy delay. Apart from the local stability analysis of the equilibrium points of the model, we find that time delay can change the stability of the system and cause Hopf bifurcation. Taking time delay as the bifurcation parameter, the critical values of delays in several cases are derived. In addition, we extend it to the random environment and study the stochastic ultimate boundedness of the stochastic process. Finally, our theoretical results are validated by numerical simulation.
Gesneriads, a Source of Resurrection and Double-Tolerant Species: Proposal of New Desiccation- and Freezing-Tolerant Plants and Their Physiological Adaptations
Authors: Legardón Ane , García-Plazaola José Ignacio
Published: January 2023

Gesneriaceae is a pantropical family of plants that, thanks to their lithophytic and epiphytic growth forms, have developed different strategies for overcoming water scarcity. Desiccation tolerance or “resurrection” ability is one of them: a rare phenomenon among angiosperms that involves surviving with very little relative water content in their tissues until water is again available. Physiological responses of desiccation tolerance are also activated during freezing temperatures, a stress that many of the resurrection gesneriads suffer due to their mountainous habitat. Therefore, research on desiccation- and freezing-tolerant gesneriads is a great opportunity for crop improvement, and some of them have become reference resurrection angiosperms (Dorcoceras hygrometrica, Haberlea rhodopensis and Ramonda myconi). However, their difficult indoor cultivation and outdoor accessibility are major obstacles for their study. Therefore, this review aims to identify phylogenetic, geoclimatic, habitat, and morphological features in order to propose new tentative resurrection gesneriads as a way of making them more reachable to the scientific community. Additionally, shared and species-specific physiological responses to desiccation and freezing stress have been gathered as a stress response metabolic basis of the family.
Autologous Human Mesenchymal Stem Cell-Based Therapy in Infertility: New Strategies and Future Perspectives
Authors: Mohamed Rasheed Zahirrah Begam , Nordin Fazlina , Wan Kamarul Zaman Wan Safwani , Tan Yuen-Fen , Abd Aziz Nor Haslinda
Published: January 2023

Infertility could be associated with a few factors including problems with physical and mental health, hormonal imbalances, lifestyles, and genetic factors. Given that there is a concern about the rise of infertility globally, increased focus has been given to its treatment for the last several decades. Traditional assisted reproductive technology (ART) has been the prime option for many years in solving various cases of infertility; however, it contains significant risks and does not solve the fundamental problem of infertility such as genetic disorders. Attention toward the utilization of MSCs has been widely regarded as a promising option in the development of stem-cell-based infertility treatments. This narrative review briefly presents the challenges in the current ART treatment of infertility and the various potential applications of autologous MSCs in the treatment of these reproductive diseases.
Critical Role of the Cortical Alveolus Protease Alveolin in Chorion Hardening In Vivo at Medaka Fertilization
Authors: Fu Bo , Wu Di , Yasumasu Shigeki , Hane Masaya , Sato Chihiro , Kitajima Ken
Published: January 2023

Alveolin is a cortical alveolus proteinase that is secreted in the perivitelline space (PVS) at fertilization to act on the chorion. Purified alveolin is known to induce chorion hardening in vitro by processing zona pellucida B (ZPB), a major chorion component. However, in vivo function of alveolin remains unclear; thus, in this study, the effects of alveolin efficiency (Alv−/−) at the organism level were investigated using the medaka, Oryzias latipes. The Alv−/− fertilized eggs were mechanically fragile; however, they developed normally and left offspring as long as they were carefully handled before hatching. A mechanical press test showed that the Alv−/− fertilized eggs were six times more fragile than the wild-type eggs. They were 35% larger owing to the enlarged PVS, 34% thinner, and permeable to even 10 kDa FITC-dextran. These results are consistent with the transmission electron microscopy observation that the periphery of the inner layers was highly porous in the Alv−/− chorion. In chorion hardening, the alveolin-mediated processing of ZPB and the transglutaminase (TGase)-mediated crosslinking of chorion components are the key steps. This study was the first to show that alveolin also processed TGase concomitantly with ZPB, which greatly facilitated the crosslinking. Thus, alveolin was concluded to be the primary trigger for chorion hardening in vivo. Furthermore, fertilization in a balanced salt solution could partially improve the impaired chorion hardening of the Alv−/− eggs fertilized in water, probably through an alveolin-independent mechanism.
Antimicrobial Spectrum of Activity and Mechanism of Action of Linear Alpha-Helical Peptides Inspired by Shrimp Anti-Lipopolysaccharide Factors
Authors: Matos Gabriel Machado , Garcia-Teodoro Beatriz , Martins Camila Pimentel , Schmitt Paulina , Guzmán Fanny , de Freitas Ana Claudia Oliveira , Stoco Patricia Hermes , Ferreira Fabienne Antunes , Stadnik Marciel João , Robl Diogo , Perazzolo Luciane Maria , Rosa Rafael Diego
Published: January 2023

Shrimp antilipopolysaccharide factors (ALFs) form a multifunctional and diverse family of antimicrobial host defense peptides (AMPs) composed of seven members (groups A to G), which differ in terms of their primary structure and biochemical properties. They are amphipathic peptides with two conserved cysteine residues stabilizing a central β-hairpin that is understood to be the core region for their biological activities. In this study, we synthetized three linear (cysteine-free) peptides based on the amino acid sequence of the central β-hairpin of the newly identified shrimp (Litopenaeus vannamei) ALFs from groups E to G. Unlike whole mature ALFs, the ALF-derived peptides exhibited an α-helix secondary structure. In vitro assays revealed that the synthetic peptides display a broad spectrum of activity against both Gram-positive and Gram-negative bacteria and fungi but not against the protozoan parasites Trypanosoma cruzi and Leishmania (L.) infantum. Remarkably, they displayed synergistic effects and showed the ability to permeabilize bacterial membranes, a mechanism of action of classical AMPs. Having shown low cytotoxicity to THP-1 human cells and being active against clinical multiresistant bacterial isolates, these nature-inspired peptides represent an interesting class of bioactive molecules with biotechnological potential for the development of novel therapeutics in medical sciences.
Significance of Wnt/β-Catenin Signal Activation for Resistance to Neoadjuvant Chemoradiotherapy in Rectal Cancer
Authors: Miyako Shoji , Matsuda Takeru , Koma Yu-ichiro , Koide Takahiro , Sawada Ryuichiro , Hasegawa Hiroshi , Yamashita Kimihiro , Harada Hitoshi , Urakawa Naoki , Goto Hironobu , Kanaji Shingo , Oshikiri Taro , Kakeji Yoshihiro
Published: January 2023

Although a therapeutic response to neoadjuvant chemoradiotherapy (NACRT) is important to improve oncological outcomes after surgery in patients with locally advanced rectal cancer, there is no reliable predictor for this. The Wnt/β-catenin signal is known to be crucial for the tumorigenesis of colorectal cancer. This study aimed to investigate the association of Wnt/β-catenin signal activation with a pathological response to NACRT. The immunohistochemical expression of nuclear and membranous β-catenin was analyzed in biopsy samples obtained from 60 patients with locally advanced rectal cancer who received curative surgery following NACRT. The association of Wnt/β-catenin signal activation with their clinical outcomes was investigated. Notably, the body mass index of these patients was significantly higher in the low nuclear β-catenin expression group. Moreover, patients in the high nuclear β-catenin expression group tended to have more advanced disease and a higher rate of positive vascular invasion than those in the low expression group. Furthermore, the rate of good histological responses was significantly higher in the low nuclear β-catenin expression group (72% vs. 37.1%, p < 0.01). Overall, relapse-free survival tended to be better in patients with low nuclear/high membranous β-catenin expression (n = 9) than in other individuals (n = 51) (p = 0.093 and p = 0.214, respectively). Activation of the Wnt/β-catenin signal pathway represented by nuclear β-catenin accumulation was significantly associated with a poor response to NACRT in patients with rectal cancer. Analysis of nuclear β-catenin accumulation before starting treatment might help predict the therapeutic response to NACRT.
Intestinal Barrier Dysfunction and Microbial Translocation in Patients with First-Diagnosed Atrial Fibrillation
Authors: Blöbaum Leon , Witkowski Marco , Wegner Max , Lammel Stella , Schencke Philipp-Alexander , Jakobs Kai , Puccini Marianna , Reißner Daniela , Steffens Daniel , Landmesser Ulf , Rauch Ursula , Friebel Julian
Published: January 2023

Background: According to the leaky gut concept, microbial products (e.g., lipopolysaccharide, LPS) enter the circulation and mediate pro-inflammatory immunological responses. Higher plasma LPS levels have been reported in patients with various cardiovascular diseases, but not specifically during early atrial fibrillation (AF). Methods: We studied data and blood samples from patients presenting with first-diagnosed AF (FDAF) (n = 80) and 20 controls. Results: Circulating biomarkers that are suggestive of mucosal inflammation (zonulin, mucosal adhesion molecule MAdCAM-1) and intestinal epithelium damage (intestinal fatty acid binding protein, IFABP) were increased in the plasma of patients with FDAF when compared to patients with chronic cardiovascular diseases but without AF. Surrogate plasma markers of increased intestinal permeability (LPS, CD14, LPS-binding protein, gut-derived LPS-neutralising IgA antibodies, EndoCAbs) were detected during early AF. A reduced ratio of IgG/IgM EndoCAbs titres indicated chronic endotoxaemia. Collagen turnover biomarkers, which corresponded to the LPS values, suggested an association of gut-derived low-grade endotoxaemia with adverse structural remodelling. The LPS concentrations were higher in FDAF patients who experienced a major adverse cardiovascular event. Conclusions: Intestinal barrier dysfunction and microbial translocation accompany FDAF. Improving gut permeability and low-grade endotoxaemia might be a potential therapeutic approach to reducing the disease progression and cardiovascular complications in FDAF.
Osteopontin Is Associated with Multiple Sclerosis Relapses
Authors: Stampanoni Bassi Mario , Buttari Fabio , Gilio Luana , Iezzi Ennio , Galifi Giovanni , Carbone Fortunata , Micillo Teresa , Dolcetti Ettore , Azzolini Federica , Bruno Antonio , Borrelli Angela , Mandolesi Georgia , Rovella Valentina , Storto Marianna , Finardi Annamaria , Furlan Roberto , Centonze Diego , Matarese Giuseppe
Published: January 2023

Background: Osteopontin, an extracellular matrix protein involved in bone remodeling, tissue repair and inflammation, has previously been associated with increased inflammation and neurodegeneration in multiple sclerosis (MS), promoting a worse disease course. Osteopontin is also likely involved in acute MS relapses. Methods: In 47 patients with relapsing-remitting MS, we explored the correlation between the time elapsed between the last clinical relapse and lumbar puncture, and the cerebrospinal fluid (CSF) levels of osteopontin and a group of inflammatory cytokines and adipokines such as resistin, plasminogen activator inhibitor-1, osteoprotegerin, interleukin (IL)-1β, IL-2, IL-6 and IL-1 receptor antagonist (IL-1ra). We also analyzed the correlations between CSF levels of osteopontin and the other CSF molecules considered. Results: Osteopontin CSF concentrations were higher in patients with a shorter time interval between the last clinical relapse and CSF withdrawal. In addition, CSF levels of osteopontin were positively correlated with the proinflammatory cytokines IL-2 and IL-6 and negatively correlated with the anti-inflammatory molecule IL-1ra. Conclusions: Our results further suggest the role of osteopontin in acute MS relapses showing that, in proximity to relapses, osteopontin expression in CSF may be increased along with other proinflammatory mediators and correlated with decreased concentrations of anti-inflammatory molecules.
In Situ Deposition of Gold Nanoparticles and L-Cysteine on Screen-Printed Carbon Electrode for Rapid Electrochemical Determination of As(III) in Water and Tea
Authors: Wang Wenjing , Yi Zhijian , Liang Qiongxin , Zhen Junjie , Wang Rui , Li Mei , Zeng Lingwen , Li Yongfang
Published: January 2023

In this study, a screen-printed carbon electrode (SPCE) based on in situ deposition modification was developed for the sensitive, rapid, easy and convenient determination of As(III) in water and tea by linear sweep anodic stripping voltammetry (LSASV). The screen-printed carbon electrodes were placed in a solution consisting of As(III) solution, chlorauric acid and L-cysteine. Under certain electrical potential, the chloroauric acid was reduced to gold nanoparticles (AuNPs) on the SPCE. L-cysteine was self-assembled onto AuNPs and promoted the enrichment of As(III), thus enhancing the determination specificity and sensitivity of As(III). The method achieved a limit of determination (LOD) of 0.91 ppb (µg L−1), a linear range of 1~200 µg L−1, an inter-assay coefficient of variation of 5.3% and good specificity. The developed method was successfully applied to the determination of As(III) in tap water and tea samples, with a recovery rate of 93.8%~105.4%, and further validated by inductively coupled plasma mass spectrometry (ICP-MS). The developed method is rapid, convenient and accurate, holding great promise in the on-site determination of As(III) in tap water and tea leaves, and it can be extended to the detection of other samples.