bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Damage Constitutive Model of Rock under Freeze-Thaw-Confining Pressure-Acid Erosion
Authors: Chen Youliang , Xiao Peng , Du Xi , Wang Suran , Fernandez-Steeger Tomas Manuel , Azzam Rafig
Published: October 2021

Aiming at the acid-etched freeze-thaw rock for geotechnical engineering in cold regions, chemical damage variables, freeze-thaw damage variables, and force damage variables were introduced to define the degree of degradation of rock materials, the law of damage evolution, the total damage variable of acid-corroded rock under the coupling action of freeze-thaw and confining pressure was deduced. The continuous damage mechanics theory was adopted to derive the damage evolution equation and constitutive model of acid-eroded rock under the coupling action of freeze-thaw and confining pressure. The theoretical derivation method was used to obtain the required model parameter expressions. Finally, the model’s rationality and accuracy were verified by the triaxial compression test data of frozen-thawed rocks. Comparing the test curve’s peak point with the peak point of the model theoretical curve, the results show that the two are in suitable agreement. The damage constitutive model can better reflect the stress-strain peak characteristics of rock during triaxial compression, verifying the rationality and reliability of the model and the method for determining the model parameters. The model extends the damage model of rock under the coupling action of freeze-thaw and confining pressure in the chemical environment and further reveals the damage mechanism and failure law of acid-corroded rock under the coupling action of freeze-thaw and confining pressure.
Parallel Dislocation Model Implementation for Earthquake Source Parameter Estimation on Multi-Threaded GPU
Authors: Lee Seongjae , Kim Taehyoun
Published: October 2021

Graphics processing units (GPUs) have been in the spotlight in various fields because they can process a massive amount of computation at a relatively low price. This research proposes a performance acceleration framework applied to Monte Carlo method-based earthquake source parameter estimation using multi-threaded compute unified device architecture (CUDA) GPU. The Monte Carlo method takes an exhaustive computational burden because iterative nonlinear optimization is performed more than 1000 times. To alleviate this problem, we parallelize the rectangular dislocation model, i.e., the Okada model, since the model consists of independent point-wise computations and takes up most of the time in the nonlinear optimization. Adjusting the degree of common subexpression elimination, thread block size, and constant caching, we obtained the best CUDA optimization configuration that achieves 134.94×, 14.00×, and 2.99× speedups over sequential CPU, 16-threads CPU, and baseline CUDA GPU implementation from the 1000×1000 mesh size, respectively. Then, we evaluated the performance and correctness of four different line search algorithms for the limited memory Broyden–Fletcher–Goldfarb–Shanno with boundaries (L-BFGS-B) optimization in the real earthquake dataset. The results demonstrated Armijo line search to be the most efficient one among the algorithms. The visualization results with the best-fit parameters finally derived by the proposed framework confirm that our framework also approximates the earthquake source parameters with an excellent agreement with the geodetic data, i.e., at most 0.5 cm root-mean-square-error (RMSE) of residual displacement.
A Block Arnoldi Algorithm Based Reduced-Order Model Applied to Large-Scale Algebraic Equations of a 3-D Field Problem
Authors: Wang Ning , Chen Jiajia , Wang Huifang , Yang Shiyou
Published: October 2021

In simulations of three-dimensional transient physics filled through a numerical approach, the order of the equation set of high-fidelity models is extremely high. To eliminate the large dimension of equations, a model order reduction (MOR) technique is introduced. In the existing MOR methods, the block Arnoldi algorithm-based MOR method is numerically stable, achieving a passively reduced order model. Nevertheless, this method performs poorly when it is applied to very wide-frequency transients. To eliminate this deficiency, multipoint MOR methods are emerging. However, it is hard to directly apply an existing multipoint MOR method to a 3-D transient field equation set. The implementation issues in a reduction process (such as the selection of expansion points, the number of moments matched at a point and the error bound) have not been explored in detail. In this respect, an adaptive multipoint model reduction model based on the Arnoldi algorithm is proposed to obtain the reduced-order models of a 3-D temperature field. The originality of this study is the proposal of a novel adaptive algorithm for selecting expansion points, matching moments automatically, using a posterior-error estimator based on temperature response coupled with a network topological method (NTM). The computational efficiency and accuracy of the proposed method are evaluated by the numerical results from solving the temperature field of a prototype insulated-gate bipolar transistor (IGBT).
Diagnosis and Treatment of MODY: An Updated Mini Review
Authors: Tshivhase Abegail , Matsha Tandi , Raghubeer Shanel
Published: October 2021

Maturity-Onset Diabetes of the Young (MODY) is the most common form of monogenic diabetes resulting from a single gene mutation. It is characterized by mild hyperglycemia, autosomal dominant inheritance, early onset of diabetes (<25 years), insulin resistance, and preservation of endogenous insulin secretion. Currently, 14 MODY subtypes have been identified, with differences in incidence, clinical features, diabetes severity and related complications, and treatment response. This type of diabetes is mostly misdiagnosed as either type 1 or type 2 diabetes mellitus because it is difficult to differentiate between these forms of diabetes due to clinical similarities, the high cost of genetic testing, and lack of awareness. As a result, thousands of patients are not receiving appropriate treatment. Accurate diagnosis would allow for more effective therapeutic management and treatment strategies that are distinct from those used for type 1 and type 2 diabetes. This review serves to explore MODY subtypes, diagnosis, and treatment, and increase awareness of MODY incidence.
Chitosan Beads Incorporated with Graphene Oxide/Titanium Dioxide Nanoparticles for Removing an Anionic Dye
Authors: Solano Moisés A. , Galan Johanna , Vallejo William , Arana Victoria A. , Grande-Tovar Carlos David
Published: October 2021

Dyes present in industrial effluents have been treated by many methods, among which adsorption stands out for its high efficiency, low costs, simple operation processes, and the absence of hazardous byproducts. In this research, two adsorbents were obtained from chitosan beads (CS) cross-linked with glutaraldehyde (GLA), graphene oxide (GO), and titanium dioxide nanoparticles (TiO2) for the adsorption of the anionic dye FD&C Red 40 used as a model pollutant. The optimum removal conditions of FD&C Red 40 dye using CS-TiO2-GLA beads were determined (pH = 1.73, TiO2 amount =279.77 mg, and initial dye concentration = 55.23 mg L−1) with a central composite design with surface response methodology (RSM). The effect of the graphene oxide (GO) in the adsorption properties of CS-TiO2-GLA beads was evaluated, showing a considerable improvement in the removal efficiency of the model dye. The intraparticle diffusion mechanism best described the adsorption kinetics for the two adsorbents. This research demonstrates the potential of chitosan beads incorporated with graphene oxide and titanium dioxide nanoparticles to remove anionic contaminants from wastewater.
RETRACTED: Chen et al. Image Super-Resolution Algorithm Based on Dual-Channel Convolutional Neural Networks. Appl. Sci. 2019, 9, 2316
Authors: Chen Yuantao , Wang Jin , Chen Xi , Sangaiah Arun , Yang Kai , Cao Zhouhong
Published: October 2021

The published article Image Super-Resolution Algorithm Based on Dual-Channel Convolutional Neural Networks [...]
Bearing Capacity of Single Pile-Friction Wheel Composite Foundation on Sand-over-Clay Deposit under V-H-M Combined Loadings
Authors: Wang Yikang , Zou Xinjun , Hu Jianfeng
Published: October 2021

This paper presents numerical modelling to investigate the bearing capacities and failure mechanisms of single pile-friction wheel composite foundation in sand-overlying-clay soil conditions under combined V-H-M (vertical-horizontal-moment) loadings. A series of detailed numerical models, with validations of centrifuge testing results, are generated to explore the potential factors influencing the bearing capacity of this composite system. Intensive parametric study is then performed to quantify the influences of the foundation geometry, soil properties, sand layer thickness, pre-vertical loading and lateral loading height on the failure envelopes in the V-H-M domain. Last but not least, an empirical design procedure is proposed based on a parametric study to predict the bearing capacity of this composite foundation under various loading conditions, which can provide guidance for its design and application.
Probiotic Characteristics of Ligilactobacillus salivarius AS22 Isolated from Sheep Dung and Its Application in Corn-Fox Tail Millet Silage
Authors: Balasubramanian Balamuralikrishnan , Soundharrajan Ilavenil , Al-Dhabi Naif Abdullah , Vijayaraghavan Ponnuswamy , Balasubramanian Kaleeswaran , Valan Arasu Mariadhas , Choi Ki Choon
Published: October 2021

The forage crops corn (Zea mays) and foxtail millet (Panicum italicum L.) are widely used as animal feed because of their high nutritive values. The ensiling of corn and foxtail millet is often associated with the growth of undesirable microbes, which cause severe loss of dry matter content during the storage periods. The selection of suitable Ligilactobacillus species for corn-fox tail millet silage production can improve the quality. In this study, we aimed to select potent lactic acid bacteria (LAB) from sheep dung and analyses their biological application such as probiotic features, antimicrobial activities and fermentation capability of silage. A total of nine Lactobacillus strains were inoculated in MRS medium to evaluate lactic acid concentration. The isolated strain, Ligilactobacillus salivarius AS22, produced a higher lactic acid level (40.2 ± 2.2 µg/mL) with high growth rates (2.24 ± 0.12 OD at 600 nm) compared to other strains. The silage treated with inoculant (L. salivarius AS22) decreased the pH value (p < 0.05) and enhanced lactic acid production (p < 0.05) than the control at ensiled silages. LAB inoculated silage had reduced numbers of fungal colonies than control (p < 0.05). In conclusion, the addition of L. salivarius AS22 improved the quality of whole corn and foxtail millet silages with significant probiotic potential.
Performance and Emissions of a Spark Ignition Engine Fueled with Water-in-Gasoline Emulsion Produced through Micro-Channels Emulsification
Authors: Tornatore Cinzia , Marchitto Luca , Teodosio Luigi , Massoli Patrizio , Bellettre Jérôme
Published: October 2021

This paper presents an experimental study investigating the effects of water-in-gasoline emulsion (WiGE) on the performance and emissions of a turbocharged PFI spark-ignition engine. The emulsions were produced through a micro-channels emulsifier, potentially capable to work inline, without addition of surfactants. Measurements were performed at a 3000 rpm speed and net Indicated Mean Effective Pressure (IMEP) of 16 bar: the engine point representative of commercial ECU map was chosen as reference. In this condition, the engine, fueled with gasoline, runs overfueled (λ = 0.9) to preserve the integrity of the turbocharger from excessive temperature, and the spark timing corresponds to the knock limit. Starting from the reference point, two different water contents in emulsion were tested, 10% and 20% by volume, respectively. For each selected emulsion, at λ = 0.9, the spark timing was advanced from the reference point value to the new knock limit, controlling the IMEP at a constant level. Further, the cooling effect of water evaporation in WiGE allowed it to work at stoichiometric condition, with evident benefits on the fuel economy. Main outcomes highlight fuel consumption improvements of about 7% under stoichiometric mixture and optimized spark timing, while avoiding an excessive increase in turbine thermal stress. Emulsions induce a slight worsening in the HC emissions, arising from the relative impact on combustion development. On the other hand, at stoichiometric condition, HC and CO emissions drop with a corresponding increase in NO.
A Novel Electromagnetic Compatibility Evaluation Method for Receivers Working under Pulsed Signal Interference Environment
Authors: Cai Shaoxiong , Li Yaoyao , Zhu Heng , Wu Xiaolin , Su Donglin
Published: October 2021

For wireless communication systems, receivers usually work under complex electromagnetic environments and are often susceptible to electromagnetic interference (EMI). With the wide application of pulse signals in various fields, the impact of pulse signals on the receivers of communication system has not been extensively studied. On the one hand, the existing receiver electromagnetic sensitivity (EMS) interference coupling effect is mainly analyzed from the perspective of energy only, without considering of different electromagnetic parameter characteristics of pulse signal, such as pulse width, repetition period, duty cycle and so on. On the other hand, there is a lack of quantitative characterization of typical performance indexes of receiver subject to pulsed interference environment, resulting in insufficient reliability and accuracy of receiver interference degree prediction and electromagnetic compatibility (EMC) evaluation. This paper focuses on the EMS interference coupling effect analysis and EMC evaluation method of receiver under pulsed interference environment. First, based on the analysis of the interference mechanism of the pulse signal on receivers, the formula for the bit error ratio (BER) is derived. Then a system model is proposed to verify the theoretical analysis results through numerical simulation. With the established relationship between the parameters of the pulsed interference and the BER performance of the receiver, a novel EMC evaluation method has been proposed. As a practical application example, the evaluation method is verified via a well-designed experiment on BeiDou Navigation Satellite System (BDS). The experiment shows that the observed phenomena are in good agreement with the conclusions of the proposed evaluation method, proving that the method is applicable to the EMC evaluation of receiver under pulsed signal interference environment.
An Integrated Spatio-Temporal Features Analysis Approach for Ocean Turbulence Using an Autonomous Vertical Profiler
Authors: Liu Xiuyan , Song Dalei , Yang Hua , Wang Xiaofeng , Nie Yunli
Published: October 2021

Turbulent energy cascade and intermittency are very important characteristics in the turbulent energy evolution process. However, understanding the temporal–spatial features of kinetic energy transfer and quantifying the correlations between different scales of turbulent energy remains an outstanding challenge. To deeply understand the spatial–temporal features in the energy transfer process, an integrated features identification and extraction method is proposed to quantitatively investigate the correlations using the ocean shear turbulence measured by an autonomous vertical reciprocating profiler (AVRP). The proposed integrated method mainly contains two parallel features analysis modules: first, temporal multiscale features structures of the nonlinear and nonstationary turbulent cascade are identified by Variational Mode Decomposition (VMD); then, the ocean microstructure shear fluctuation data are decomposed into a series of intrinsic mode functions (IMFs), which are characterized by different time scales and frequency bandwidths. The local features of energy transfer are identified when the local intermittency peaks overlap and the phase-synchronization case occurs between two neighboring scales; second, the spatial statistical characteristics of the turbulent energy dissipation are quantitatively studied. The cumulative probability distribution functions (CPDFs) of kinetic energy dissipation are approximated well by a normal distribution, indicating that the turbulent dissipation process exhibits a robust spatial scaling correlation and a few intense dissipation locations dominate the integrated process. Finally, the proposed integrated method is evaluated through experiments using an autonomous vertical reciprocating profiler deployed in the South China Sea. Preliminary experimental results show that the proposed novel method is useful to improve our understanding of turbulent energy transfer and the evolution process in the ocean dynamic systems.
Assessment of Nerve Repair Augmented with Adipose-Derived Mast Cells in an Animal Model
Authors: Bloanca Vlad , Haragus Horia , Campean Anca-Maria , Cosma Andrei , Bratu Tiberiu , Crainiceanu Zorin
Published: October 2021

We aimed to analyze the involvement of adipose-sourced mast cells in nerve repair. Sixteen Wistar rats underwent complete transection of the sciatic nerves followed by either direct neurorrhaphy or neurorrhaphy and processed abdominal fat. Four animals were used as controls. Specimens were obtained at 4 and 10 weeks and analyzed using luxol fast blue stain, mast cell tryptase and CD34 (for angiogenesis) per microscopic field ×200. When assessed by luxol fast blue, normal nerves showed an average of 2–3 mast cells/field. At 4 weeks, there were 9.25 for the simple nerve sutures and 16 for the augmented repairs. At 10 weeks, there were 23 and 27.6. When assessed by mast cell tryptase, there were no positives in the controls. At 4 weeks, we found an average of 4 in the simple sutures and 2.5 in the augmented repairs. At 10 weeks, there were 4.5 and 0.2. In controls, there were 1–2 CD34+ blood vessels per field. At 4 weeks, simple repairs showed an average of 4 and, in those with adipose addition, 5.5. At 10 weeks, there were 7 and 12. Mechanically processed adipose tissue augmented nerve repair does not seem to increase mast cell expression but may support angiogenesis in an experimental model.
Informatization Management as a Tool to Improve Internal School Control Systems in the Russian Federation (Using Catering as an Example)
Authors: Mindzaeva Eteri V. , Arinushkina Anna A.
Published: October 2021

This paper presents the results from monitoring the organization of catering for children in general education institutions. Monitoring was conducted in August–September 2020. We collected relevant databases for 85 Russian subjects: the total number of indicators—113, the total number of sub-indicators—347, and the total number of data—76,414. This paper investigates the problems surrounding resource provision in regard to organizing nutrition for schoolchildren in the Russian Federation. We analyzed the structure of the informatization in regard to the provision of hot meals for schoolchildren in Russian regions. Moreover, we present cases and best practices surrounding informatization management and personalization of children’s nutrition. The research results reveal that Russia possesses a unified regional information system for accounting/monitoring the organization of children’s nutrition, as an independent specialized information resource (in regard to catering). This paper identifies the levels of information technology used in school nutritional programs for each federal district. We present the results of the analysis, the availability of information resources, and the possibility of automated non-cash payments for meals in general education institutions. Moreover, we analyzed information resources and generated reporting documents on the organization of nutrition for schoolchildren in Russia. Finally, we analyzed the automated assessment of satisfaction, in regard to catering and food quality among children and their parents in Russian regions.
Carbon–Heteroatom Bond Formation via Coupling Reactions Performed on a Magnetic Nanoparticle Bed
Authors: Tajbakhsh Mahmood , Ramezani Ali , Qandalee Mohammad , Falahati Mobina , Durán-Valle Carlos J. , Izquierdo Silvia , López-Coca Ignacio M.
Published: October 2021

Cross-coupling reactions leading to carbon–heteroatom bonds yield compounds that attract substantial interest due to their role as structural units in many synthetic protocols for bioactive and natural products. Therefore, many research works aim at the improvement of heterogeneous catalytic protocols. We have studied the use of magnetite nanoparticles and solid base compounds in organic synthetic reactions in carbon–heteroatom bond formation because they can be flocculated and dispersed, and reversibly controlled by applying a magnetic field. In this work, we have developed an efficient and simple synthetic approach for the C–O/C–N cross-coupling reaction under ligand-free conditions by using CuI as a catalyst and KF/Fe3O4 as a base. We performed the nucleophilic aromatic substitution of electron-deficient aryl halides and phenols. It was found that both the solvent nature and the base have a profound influence on the reaction process. This approach affords good to excellent yields of arylated products. KF/Fe3O4 displayed convenient magnetic properties and could be easily separated from the reaction using a magnet and recycled several times without significant loss of catalytic activity. This method has been successfully investigated for the Ullmann coupling reaction.
Competitiveness of Quantitative Polymerase Chain Reaction (qPCR) and Droplet Digital Polymerase Chain Reaction (ddPCR) Technologies, with a Particular Focus on Detection of Antibiotic Resistance Genes (ARGs)
Authors: Park Sol , Rana Anita , Sung Way , Munir Mariya
Published: October 2021

With fast-growing polymerase chain reaction (PCR) technologies and various application methods, the technique has benefited science and medical fields. While having strengths and limitations on each technology, there are not many studies comparing the efficiency and specificity of PCR technologies. The objective of this review is to summarize a large amount of scattered information on PCR technologies focused on the two majorly used technologies: qPCR (quantitative polymerase chain reaction) and ddPCR (droplet-digital polymerase chain reaction). Here we analyze and compare the two methods for (1) efficiency, (2) range of detection and limitations under different disciplines and gene targets, (3) optimization, and (4) status on antibiotic resistance genes (ARGs) analysis. It has been identified that the range of detection and quantification limit varies depending on the PCR method and the type of sample. Careful optimization of target gene analysis is essential for building robust analysis for both qPCR and ddPCR. In our era where mutation of genes may lead to a pandemic of viral infectious disease or antibiotic resistance-induced health threats, this study hopes to set guidelines for meticulous detection, quantification, and analysis to help future prevention and protection of global health, the economy, and ecosystems.
The Microbiome’s Function in Disorders of the Urinary Bladder
Authors: Choi Hae-Woong , Lee Kwang-Woo , Kim Young-Ho
Published: October 2021

The introduction of next generation sequencing techniques has enabled the characterization of the urinary tract microbiome, which resulted in the rejection of the long-held notion of urinary bladder sterility. Since the discovery and confirmation of the human bladder microbiome, an increasing number of studies have defined this microbial community and understand better its relationship to urinary pathologies. The composition of microbial communities in the urinary tract is linked to a variety of urinary diseases. The purpose of this review is to provide an overview of current information about the urinary microbiome and diseases as well as the development of novel treatment methods.
Design and Manufacturing of Adaptive Facades in a Life Cycle Approach: A Survey on Challenges and Solutions in the Italian Building Industry
Authors: Crespi Manuela
Published: October 2021

The market of Adaptive Building Skins has been growing at a slow but incremental speed, as these technologies ensure better indoor climatic comfort and more efficient energy management than traditional solutions. Nonetheless, if we acknowledge the building as a system of physical qualities oriented to overall environmental performance, the resource optimization has to be extended to considering a wider range of environmental impacts along the entire building life cycle. For this purpose, the Life Cycle Assessment (LCA) method is recognized by stakeholders as the most world-renowned standardized tool for weighting environmental impacts. The aim of this study is to scrutinize the state of the art of LCA among stakeholders enrolled in the design and manufacturing of building and adaptive facades in the Italian market. Data have been collected throughout interviews and an online survey focusing on investigating the knowledge and experience level of participants. Results not only draw the attention to develop new market models by implementing sustainable building protocols concerning adaptive technologies, but also provided a positive assessment on the usability degree of a parametric design mapping based on a systemic and life-cycle-oriented approach to achieve environmental scopes and introduce competitive factors and boost innovation in the Italian building industry.
Towards Design and Development of a Data Security and Privacy Risk Management Framework for WBAN Based Healthcare Applications
Authors: Paul Pangkaj Chandra , Loane John , McCaffery Fergal , Regan Gilbert
Published: October 2021

Assuring security and privacy of data is a key challenge for organizations when developing WBAN applications. The reasons for this challenge include (i) developers have limited knowledge of market-specific regulatory requirements and security standards, and (ii) there are a vast number of security controls with insufficient implementation detail. To address these challenges, we have developed a WBAN data security and privacy risk management framework. The goal of this paper is trifold. First, we present the methodology used to develop the framework. The framework was developed by considering recommendations from legislation and standards. Second, we present the findings from an initial validation of the framework’s usability and effectiveness of the security and privacy controls. Finally, we present an updated version of the framework and explain how it addresses the aforementioned challenges.
A Haze Prediction Method Based on One-Dimensional Convolutional Neural Network
Authors: Zhang Ziyan , Tian Jiawei , Huang Weizheng , Yin Lirong , Zheng Wenfeng , Liu Shan
Published: October 2021

In recent years, more and more people are paying close attention to the environmental problems in metropolitan areas and their harm to the human body. Among them, haze is the pollutant that people are most concerned about. The demand for a method to predict the haze level for the public and academics keeps rising. In order to predict the haze concentration on a time scale in hours, this study built a haze concentration prediction method based on one-dimensional convolutional neural networks. The gated recurrent unit method was used for comparison, which highlights the training speed of a one-dimensional convolutional neural network. In summary, the haze concentration data of the past 24 h are used as input and the haze concentration level on the next moment as output such that the haze concentration level on the time scale in hours can be predicted. Based on the results, the prediction accuracy of the proposed method is over 95% and can be used to support other studies on haze prediction.
Genetics of Inner Ear Malformations: A Review
Authors: Brotto Davide , Sorrentino Flavia , Cenedese Roberta , Avato Irene , Bovo Roberto , Trevisi Patrizia , Manara Renzo
Published: October 2021

Inner ear malformations are present in 20% of patients with sensorineural hearing loss. Although the first descriptions date to the 18th century, in recent years the knowledge about these conditions has experienced terrific improvement. Currently, most of these conditions have a rehabilitative option. Much less is known about the etiology of these anomalies. In particular, the evolution of genetics has provided new data about the possible relationship between inner ear malformations and genetic anomalies. In addition, in syndromic condition, the well-known presence of sensorineural hearing loss can now be attributed to the presence of an inner ear anomaly. In some cases, the presence of these abnormalities should be considered as a characteristic feature of the syndrome. The present paper aims to summarize the available knowledge about the possible relationships between inner ear malformations and genetic mutations.
A New Transformer-Less Structure for a Boost DC-DC Converter with Suitable Voltage Stress
Authors: Mohammadzadeh Shahir Farzad , Gheisarnejad Meysam , Khooban Mohammad-Hassan
Published: October 2021

In this paper, a new structure is proposed for a boost dc–dc converter based on the voltage-lift (VL) technique. The main advantages of the proposed converter are its lack of transformer, simple structure, free and low input current ripple, high voltage gain capability by using an input source, suitable voltage stress on semiconductors and lower output capacitance. Herein, the analysis of the proposed converter operating and its elements voltage and current relations in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are presented, and the voltage gain of each operating mode is individually calculated. Additionally, the critical inductance, current stress of switches, calculation of passive components’ values and efficiency are analyzed. In addition, the proposed converter is compared with other studied boost converters in terms of ideal voltage gain in the CCM and the number of active and passive components, maximum voltage stress on semiconductors, and situation of input current ripples. The correctness of the theoretical concepts is examined from the experimental results using the laboratory prototype.
Existence of Mild Solutions for Multi-Term Time-Fractional Random Integro-Differential Equations with Random Carathéodory Conditions
Authors: Diop Amadou , Du Wei-Shih
Published: October 2021

In this paper, we investigate the existence of mild solutions to a multi-term fractional integro-differential equation with random effects. Our results are mainly relied upon stochastic analysis, Mönch’s fixed point theorem combined with a random fixed point theorem with stochastic domain, measure of noncompactness and resolvent family theory. Under the condition that the nonlinear term is of Carathéodory type and satisfies some weakly compactness condition, we establish the existence of random mild solutions. A nontrivial example illustrating our main result is also given.
Is the Gut Microbiome a Target for Adjuvant Treatment of COVID-19?
Authors: Hilpert Kai
Published: October 2021

High expression of the transmembrane protein angiotensin I converting enzyme 2 (ACE2), more than 100-times higher as in the lung, and transmembrane serine protease 2 (TMPRSS2) in the gastrointestinal tract leads to infection with SARS-CoV-2. According to meta-analysis data, 9.8–20% of COVID-19 patients experience gastrointestinal symptoms, where diarrhoea is the most frequent, and about 50% shed viruses with high titre through their faeces, where a first faecal transmission was reported. Furthermore, gut inflammation, intestinal damage, and weakening of the gut mucosal integrity that leads to increased permeability has been shown in different studies for COVID-19 patients. This can lead to increased inflammation and bacteraemia. Low mucosal integrity combined with low intestinal damage is a good predictor for disease progression and submission to the intensive care unit (ICU). Several pilot studies have shown that the gut microbiome of COVID-19 patients is changed, microbial richness and diversity were lower, and opportunistic pathogens that can cause bacteraemia were enriched compared to a healthy control group. In a large proportion of these patients, dysbiosis was not resolved at discharge from the hospital and one study showed dysbiosis is still present after 3 months post COVID-19. Consequently, there might be a link between dysbiosis of the gut microbiome in COVID-19 patients and chronic COVID-19 syndrome (CCS). Various clinical trials are investigating the benefit of probiotics for acute COVID-19 patients, the majority of which have not reported results yet. However, two clinical trials have shown that a certain combination of probiotics is beneficial and safe for acute COVID-19 patients. Mortality was 11% for the probiotic treatment group, and 22% for the control group. Furthermore, for the probiotic group, symptoms cleared faster, and an 8-fold decreased risk of developing a respiratory failure was calculated. In conclusion, evidence is arising that inflammation, increased permeability, and microbiome dysbiosis in the gut occur in COVID-19 patients and thus provide new targets for adjuvant treatments of acute and chronic COVID-19. More research in this area is needed.
Facial Hair Decreases Fit Factor of Masks and Respirators in Healthcare Providers
Authors: De-Yñigo-Mojado Borja , Becerro-de-Bengoa-Vallejo Ricardo , Losa-Iglesias Marta Elena , Madera-García Javier , Rodríguez-Sanz David , Calvo-Lobo Cesar , López-López Daniel , Angulo-Carrere María Teresa , San-Antolín Marta
Published: October 2021

In response to the current state of the COVID-19 pandemic, healthcare providers are using common surgical masks and filtering respirators in conjunction with the presence of facial hair, which could lead to a large number of particles passing into their respiratory system. The purpose of this study was to determine the fit factor effectiveness of filtering respirators and surgical masks in bearded versus non-bearded healthcare providers. A controlled randomized clinical trial (NCT04391010) was carried out, analyzing a sample of 63 healthcare providers. The fit factors of surgical masks and FFP3 filtering respirators for healthcare providers with (n = 32) and without (n = 31) facial hair were compared. Fit factors were measured during an exercises protocol in which healthcare providers wore surgical masks and FFP3 filtering respirators. Surgical mask fit factor comparisons did not show significant differences (p > 0.05) between healthcare providers with and without facial hair. In contrast, filtering respirator fit factor comparisons showed statistically significant differences (p < 0.01) between both groups, indicating that healthcare providers with facial hair showed lower fit factor scores, which implies a worse fit factor with respect to healthcare providers without facial hair. The fit factor effectiveness of filtering respirators was reduced in healthcare providers with facial hair. The authors of this paper encourage healthcare providers to trim their beards during filtering respirator use or wear full-mask filtering facepiece respirators, especially during the COVID-19 pandemic.
Red Blood Cells’ Thermodynamic Behavior in Neurodegenerative Pathologies and Aging
Authors: Todinova Svetla , Krumova Sashka , Bogdanova Desislava , Danailova Avgustina , Zlatareva Elena , Kalaydzhiev Nikolay , Langari Ariana , Milanov Ivan , Taneva Stefka G.
Published: October 2021

The main trend of current research in neurodegenerative diseases (NDDs) is directed towards the discovery of novel biomarkers for disease diagnostics and progression. The pathological features of NDDs suggest that diagnostic markers can be found in peripheral fluids and cells. Herein, we investigated the thermodynamic behavior of the peripheral red blood cells (RBCs) derived from patients diagnosed with three common NDDs—Parkinson’s disease (PD), Alzheimer’s disease (AD), and amyotrophic lateral sclerosis (ALS) and compared it with that of healthy individuals, evaluating both fresh and aged RBCs. We established that NDDs can be differentiated from the normal healthy state on the basis of the variation in the thermodynamic parameters of the unfolding of major RBCs proteins—the cytoplasmic hemoglobin (Hb) and the membrane Band 3 (B3) protein. A common feature of NDDs is the higher thermal stability of both Hb and B3 proteins along the RBCs aging, while the calorimetric enthalpy can distinguish PD from ALS and AD. Our data provide insights into the RBCs thermodynamic behavior in two complex and tightly related phenomena—neurodegenerative pathologies and aging, and it suggests that the determined thermodynamic parameters are fingerprints of the altered conformation of Hb and B3 protein and modified RBCs’ aging in the studied NDDs.
The Role of Microglia in the Development of Neurodegenerative Diseases
Authors: Lee Jae-Won , Chun Wanjoo , Lee Hee Jae , Kim Seong-Man , Min Jae-Hong , Kim Doo-Young , Kim Mun-Ock , Ryu Hyung Won , Lee Su Ui
Published: October 2021

Microglia play an important role in the maintenance and neuroprotection of the central nervous system (CNS) by removing pathogens, damaged neurons, and plaques. Recent observations emphasize that the promotion and development of neurodegenerative diseases (NDs) are closely related to microglial activation. In this review, we summarize the contribution of microglial activation and its associated mechanisms in NDs, such as epilepsy, Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD), based on recent observations. This review also briefly introduces experimental animal models of epilepsy, AD, PD, and HD. Thus, this review provides a better understanding of microglial functions in the development of NDs, suggesting that microglial targeting could be an effective therapeutic strategy for these diseases.
Effect of Silver Nanoparticles on Blue Light Phototoxicity against Fusobacterium nucleatum
Authors: Jeffet Uziel , Livne Shiri , Rahmanov Arkadi , Sterer Nir
Published: October 2021

A previous study showed that sub-lethal exposure of blue light caused cell membrane damage in Fusobacterium nucleatum (Fn). The aim of the present study was to test the combined effect of blue light and silver nanoparticles against Fn. Bacterial suspensions were exposed to blue light (400–500 nm) with or without silver nanoparticles (10 nm). Exposed and non-exposed samples were studied for malodor production (Odor judge scores), VSC levels (Halimeter), reactive oxygen species (ROS) production (fluorimeter), and bacterial cell membrane damage (fluorescence microscopy). The results showed that combining blue light exposure and silver nanoparticles significantly reduced malodor and VSC production by Fn concomitant with increased ROS levels and bacterial cell membrane damage. These results suggest that silver nanoparticles may increase blue light phototoxicity against Fn.
Development of Strategic Resilience Framework for Small Businesses Post-COVID-19
Authors: Gorjian Khanzad Zahra , Gooyabadi Ali A.
Published: October 2021

The detrimental transboundary effect of COVID-19 exhibits an unprecedented circumstance for organizational resilience. This proposed research paper aims to analyze the impact of COVID-19 on small businesses (SBs) worldwide towards developing a strategic resilience framework. This framework enables the development of resilient strategies that SBs can utilize to survive and sustain their livelihood post-COVID-19. It is profoundly challenging to cope with the consequences of a devastating global pandemic with enormous negative economic side-effects and survive given reduced income, jobs lost, etc. This paper utilizes different models, such as Meyer’s Model, the PESTEL model, and the Comprehensive Organizational Model, to discuss the process of adaptations to market shocks. This adaptation methodology consists of different anticipatory, responsive, and rehabilitation phases, leading to organizational resilience. A conceptual framework is proposed through a qualitative analysis of existing academic literature concerning strategic resilience for small businesses facing environmental jolts such as COVID-19. By developing the proposed strategic resilience framework, other methods and theories, including the adaptability of small- and medium-sized organizations, will be addressed.
Nanoporous Carbon Magnetic Hybrid Derived from Waterlock Polymers and Its Application for Hexavalent Chromium Removal from Aqueous Solution
Authors: Asimakopoulos Georgios , Karakassides Angeliki , Baikousi Maria , Gioti Christina , Moschovas Dimitrios , Avgeropoulos Apostolos , Bourlinos Athanasios B. , Douvalis Alexios P. , Salmas Constantinos E. , Karakassides Michael A.
Published: October 2021

Sodium polyacrylate is the superabsorbent waterlock polymer used in disposable diapers, which are the third largest single consumer item in landfills. As diapers are difficult to recycle, their use produces an incredible amount of environmental waste. In the present article, we present a reliable and facile approach to transform sodium polyacrylate, the main constitute in the used diapers, in a carbon-based magnetic sorbent material, capable for use in environmental applications. A nanoporous carbon magnetic hybrid material was prepared by reacting NaPA with iron acetate species under chemical activation conditions. Analysis of the characterization results revealed, the creation of a nanoporous structure, with high specific surface area value (SgBET = 611 m2/g), along with the formation of nanosized zero valent iron nanoparticles and iron carbide (Fe3C), inside the carbon pore system. 57Fe Mössbauer spectroscopy verified also the existence of these two main iron-bearing phases, as well as additional minor magnetic phases, such as Fe3O4 and γ-Fe2O3. Vibrating sample magnetometry (VSM) measurements of the obtained hybrid confirmed its ferromagnetic/ferrimagnetic behavior. The hybrid material demonstrated a rapid sorption of Cr(VI) ions (adsorption capacity: 90 mg/g, 24 h, pH = 3). The results showed highly pH-dependent sorption efficiency of the hybrids, whereas a pseudo-second-order kinetic model described their kinetics.
Development and Validation of a Novel Serum Prognostic Marker for Patients with Metastatic Colorectal Cancer on Regorafenib Treatment
Authors: Su Yu-Li , Tsai Kai-Lung , Chiu Tai-Jan , Lin Yueh-Ming , Lee Ko-Chao , Lu Chien-Chang , Chen Hong-Hwa , Wu Chia-Che , Hsu Hung-Chih
Published: October 2021

(1) Background: To investigate the prognostic value of cancer-inflammation prognostic index (CIPI) in patients with metastatic colorectal cancer (mCRC) on regorafenib treatment; (2) Methods: Patients with mCRC who were given regorafenib as later-line treatment at Kaohsiung and Linkou Chang-Gung Memorial Hospital between November 2014 and January 2021 were consecutively enrolled. All relevant clinicopathologic, laboratory data and survival status were recorded. Independent prognostic factors were determined by the multivariate Cox regression method; (3) Results: In total, 106 patients in the training cohort and 250 in the validation cohort were enrolled. The median OS for patients with CIPI ≥ 300 and < 300 in the training cohort was 3.8 and 9.0 months, respectively (hazard ratio (HR) 2.78, 95% confidence interval (CI) 1.82–4.23; p < 0.0001). Time to regorafenib, liver metastasis and CIPI were independent factors by multivariate Cox regression analyses. A new scoring model demonstrated a good discriminatory ability to risk stratification of a patient’s survival; (4) Conclusions: We identified CIPI as a novel serum marker highly associated with overall survival in patients with mCRC receiving regorafenib treatment. Further confirmatory studies are warranted.
Novel Molecular Mechanism of Lenalidomide in Myeloid Malignancies Independent of Deletion of Chromosome 5q
Authors: Park Isaac , Phan Tra Mi , Fang Jing
Published: October 2021

Lenalidomide as well as other immunomodulatory drugs (IMiDs) have achieved clinical efficacies in certain sub-types of hematologic malignancies, such as multiple myeloma, lower-risk myelodysplastic syndromes (MDS) with a single deletion of chromosome 5q (del(5q)) and others. Despite superior clinical response to lenalidomide in hematologic malignancies, relapse and resistance remains a problem in IMiD-based therapy. The last ten years have witnessed the discovery of novel molecular mechanism of IMiD-based anti-tumor therapy. IMiDs bind human cereblon (CRBN), the substrate receptor of the CRL4 E3 ubiquitin ligase complex. Binding of CRBN with IMiDs leads to degradation of the Ikaros family zinc finger proteins 1 and 3 (IKZF1 and IKZF3) and casein kinase 1 alpha. We have found that lenalidomide-mediated degradation of IKZF1 leads to activation of the G protein-coupled receptor 68 (GPR68)/calcium/calpain pro-apoptotic pathway and inhibition of the regulator of calcineurin 1 (RCAN1)/calcineurin pro-survival pathway in MDS and acute myeloid leukemia (AML). Calcineurin inhibitor Cyclosporin-A potentiates the anti-leukemia activity of lenalidomide in MDS/AML with or without del(5q). These findings broaden the therapeutic potential of IMiDs. This review summarizes novel molecular mechanism of lenalidomide in myeloid malignancies, especially without del(5q), in the hope to highlight novel therapeutic targets.
The Emerging Influences of Alpha-Fetoprotein in the Tumorigenesis and Progression of Hepatocellular Carcinoma
Authors: Xu Ye , Guo Qinglong , Wei Libin
Published: October 2021

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide, and its mortality rate is the third-highest, after lung cancer and colorectal cancer. Currently, systematic targeted therapies for HCC mainly include multiple kinase inhibitors and immunotherapy. However, these drugs carry a black-box warning about the potential for inducing severe toxicity, and they do not significantly prolong the survival period of patients due to the highly heterogeneous characteristics of HCC etiology. In order to improve the prediction, effective treatment and prognosis of HCC, the tools and different biomarkers in clinical practices are recommended. Alpha-fetoprotein (AFP) is the earliest and the most widely used serum marker in the detection of HCC. Interestingly, serum AFP and cytoplasmic AFP show different, even opposite, roles in the cancer progression of HCC. This review focuses on biological characteristics, regulatory mechanisms for gene expression, emerging influences of AFP in HCC and its possible implications in HCC-targeted therapy.
Therapeutic Targeting of Cancer Stem Cells in Lung, Head and Neck, and Bladder Cancers
Authors: Mudra Sarah E. , Sadhukhan Pritam , Ugurlu M. Talha , Alam Shorna , Hoque Mohammad O.
Published: October 2021

Resistance to cancer therapy remains a significant obstacle in treating patients with various solid malignancies. Exposure to current chemotherapeutics and targeted agents invariably leads to therapy resistance, heralding the need for novel agents. Cancer stem cells (CSCs)—a subpopulation of tumor cells with capacities for self-renewal and multi-lineage differentiation—represent a pool of therapeutically resistant cells. CSCs often share physical and molecular characteristics with the stem cell population of the human body. It remains challenging to selectively target CSCs in therapeutically resistant tumors. The generation of CSCs and induction of therapeutic resistance can be attributed to several deregulated critical growth regulatory signaling pathways such as WNT/β-catenin, Notch, Hippo, and Hedgehog. Beyond growth regulatory pathways, CSCs also change the tumor microenvironment and resist endogenous immune attack. Thus, CSCs can interfere with each stage of carcinogenesis from malignant transformation to the onset of metastasis to tumor recurrence. A thorough review of novel targeted agents to act against CSCs is fundamental for advancing cancer treatment in the setting of both intrinsic and acquired resistance.