bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrophobin CmHYD1 Is Involved in Conidiation, Infection and Primordium Formation, and Regulated by GATA Transcription Factor CmAreA in Edible Fungus, Cordyceps militaris
Authors: Li Xiao , Wang Fen , Liu Mengqian , Dong Caihong
Published: August 2021

Hydrophobins are a family of small proteins exclusively secreted by fungi, and play a variety of roles in the life cycle. Cmhyd1, one of the hydrophobin class II members in Cordyceps militaris, has been shown to have a high transcript level during fruiting body development. Here, deletion of Cmhyd1 results in reduction in aerial mycelia, conidiation, hydrophobicity and infection ability, and complete inhibition of pigmentation and primordium differentiation. Cmhyd1 plays roles in conidiation and cuticle-bypassing infection by regulating the transcripts of frequency clock protein, Cmfrq, and velvet protein, Cmvosa, as well as primordium formation via the mitogen-activated protein kinase signaling pathway. Cmhyd1 also participates in stress response, including tolerance of mycelia to osmotic and oxidative stresses, and conidia to high or low temperatures. CmAreA, a transcription factor of nitrogen regulatory, is recruited to the promoter of Cmhyd1 and activates the transcription of Cmhyd1 with coactivator CmOTam using electrophoretic mobility shift assays and transient luciferase expression in tobacco. Furthermore, CmHYD1 is proved to regulate the transcription of Cmarea at different developmental stages via a positive feedback loop. These results reveal the diverse roles and regulation of Cmhyd1 in C. militaris, and provide insights into the developmental regulatory mechanism of mushrooms.
Genomic and Experimental Investigations of Auriscalpium and Strobilurus Fungi Reveal New Insights into Pinecone Decomposition
Authors: Wang Panmeng , Xu Jianping , Wu Gang , Liu Tiezhi , Yang Zhu L.
Published: August 2021

Saprophytic fungi (SPF) play vital roles in ecosystem dynamics and decomposition. However, because of the complexity of living systems, our understanding of how SPF interact with each other to decompose organic matter is very limited. Here we studied their roles and interactions in the decomposition of highly specialized substrates between the two genera Auriscalpium and Strobilurus fungi-colonized fallen pinecones of the same plant sequentially. We obtained the genome sequences from seven fungal species with three pairs: A. orientale-S. luchuensis, A. vulgare-S. stephanocystis and A. microsporum-S. pachcystidiatus/S. orientalis on cones of Pinus yunnanensis, P. sylvestris and P. armandii, respectively, and the organic profiles of substrate during decomposition. Our analyses revealed evidence for both competition and cooperation between the two groups of fungi during decomposition, enabling efficient utilization of substrates with complementary profiles of carbohydrate active enzymes (CAZymes). The Auriscalpium fungi are highly effective at utilizing the primary organic carbon, such as lignin, and hemicellulose in freshly fallen cones, facilitated the invasion and colonization by Strobilurus fungi. The Strobilurus fungi have genes coding for abundant CAZymes to utilize the remaining organic compounds and for producing an arsenal of secondary metabolites such as strobilurins that can inhibit other fungi from colonizing the pinecones.
The Effect of Radiotherapy on Diffuse Low-Grade Gliomas Evolution: Confronting Theory with Clinical Data
Authors: Adenis Léo , Plaszczynski Stéphane , Grammaticos Basile , Pallud Johan , Badoual Mathilde
Published: August 2021

Diffuse low-grade gliomas are slowly growing tumors that always recur after treatment. In this paper, we revisit the modeling of the evolution of the tumor radius before and after the radiotherapy process and propose a novel model that is simple yet biologically motivated and that remedies some shortcomings of previously proposed ones. We confront this with clinical data consisting of time series of tumor radii from 43 patient records by using a stochastic optimization technique and obtain very good fits in all cases. Since our model describes the evolution of a tumor from the very first glioma cell, it gives access to the possible age of the tumor. Using the technique of profile likelihood to extract all of the information from the data, we build confidence intervals for the tumor birth age and confirm the fact that low-grade gliomas seem to appear in the late teenage years. Moreover, an approximate analytical expression of the temporal evolution of the tumor radius allows us to explain the correlations observed in the data.
Use of Lipid-Modifying Agents for the Treatment of Glomerular Diseases
Authors: Ge Mengyuan , Merscher Sandra , Fornoni Alessia
Published: August 2021

Although dyslipidemia is associated with chronic kidney disease (CKD), it is more common in nephrotic syndrome (NS), and guidelines for the management of hyperlipidemia in NS are largely opinion-based. In addition to the role of circulating lipids, an increasing number of studies suggest that intrarenal lipids contribute to the progression of glomerular diseases, indicating that proteinuric kidney diseases may be a form of “fatty kidney disease” and that reducing intracellular lipids could represent a new therapeutic approach to slow the progression of CKD. In this review, we summarize recent progress made in the utilization of lipid-modifying agents to lower renal parenchymal lipid accumulation and to prevent or reduce kidney injury. The agents mentioned in this review are categorized according to their specific targets, but they may also regulate other lipid-relevant pathways.
CSR Unconscious Consumption by Generation Z in the COVID-19 Era—Responsible Heretics Not Paying CSR Bonus?
Authors: Pelikánová Radka MacGregor , Hála Martin
Published: August 2021

The COVID-19 pandemic brought a myriad of challenges and opportunities and has influenced the modern concept of sustainability as projected into the Corporate Social Responsibility (CSR) and the underlying multi-stakeholder model. The new generation of consumers, Generation Z, has progressively increased its participation in the market and its shopping trends have been impacting the entire CSR scenery. However, little is known about their attitudes, consumption preferences and expectations. In Spring 2021, this induced a pioneering case study survey involving members of Generation Z, students from a private university in Prague, focusing on their (lack of) readiness to pay any “CSR bonus”. The principal research aim was to study and understand the rather surprising unwillingness of a solvent part of the new generation of consumers to support CSR during the COVID-19 era by paying at least a symbolic CSR bonus. A formal survey involving a questionnaire, replied to by 228 students, out of which 18 totally rejected the CSR bonus, was assessed via contingency tables. It was accompanied by a complementary questioning via an informal interview and glossing. This plethora of data was processed by meta-analysis and lead to an unexpected proposition: prima facie sustainability heretics denying to pay any CSR bonus can be conscious consumers and responsible and progressive supporters of the sustainability and CSR. Their rejection is a deontological cry in a desert for more transparency, trust and the rule of law.
What Microeconomic Fundamentals Drove Global Oil Prices during 1986–2020?
Authors: Malliaris Anastasios G. , Malliaris Mary
Published: August 2021

The global financial crisis of 2007–2009 caused major economic disturbances in the oil market. In this paper, we consider five variables that describe the microeconomics of the supply of and demand for oil, and evaluate their importance before, during and after the global financial crisis. We consider five dissimilar regimes during the period of January 1986 to the end of 2020: two regimes prior to the global financial crisis, the regime during the crisis, and two regimes after the crisis. The main hypothesis tested is that oil fundamentals of supply and demand remained important, even though the five regimes were dissimilar. We built five boosted and over-fitted neural networks to capture the exact relationships between spot oil prices and oil data related to these prices. This analysis shows that, while the inputs into an accurate neural network can remain the same, the impact of each variable can change considerably during different regimes.
Kidney Pathology and Outcomes in ANCA-Associated Vasculitis: Retrospective Analysis of 85 Patients
Authors: Zakharova Elena , Zykova Anastasiia , Makarova Tatyana , Leonova Eugenia , Stolyarevich Ekaterina
Published: August 2021

ANCA-associated vasculitis (AAV) poses a significant risk of kidney failure; kidney biopsy remains a key prognostic tool. The histopathologic classification of AAV glomerulonephritis (GN) developed by Berden et al. showed correlation between GN classes and kidney outcomes; ANCA Renal Risk Score (ARRS) included tubular atrophy and interstitial fibrosis (TA/IF) as an additional parameter for risk assessment. We aimed to evaluate kidney survival across AAV GN classes and ARRS groups. A single-center retrospective study included 85 adult patients with biopsy-proven AAV kidney disease followed in the period of 2000–2020. Primary outcome was kidney survival at the end of 18 (5; 66) months follow-up, and kidney death was considered as stage 5 CKD. We found significant differences in kidney survival for sclerotic, mixed, crescentic and focal AAV GN classes: 19%, 76.2%, 91.7% and 100%, respectively (p = 0.009). Kidney survival was 0%, 75.6% and 100% for the high-, medium- and low-risk ARRS groups, respectively (p < 0.001); TA/IF analysis showed kidney survival at 49.6% vs. 87.7% for widespread and mild TA/IF, respectively (p = 0.003). Kidney survival was significantly lower in anti-MPO-ANCA versus anti-PR3-ANCA carriers (50.3% and 78.1%, respectively, p = 0.045). We conclude that unfavorable AAV kidney outcomes are associated with sclerotic GN class by Berden’s classification, ARRS high risk group, and anti-MPO-ANCA subtype.
Flood Risk Assessment under Land Use and Climate Change in Wuhan City of the Yangtze River Basin, China
Authors: Li Zhihui , Song Keyu , Peng Lu
Published: August 2021

Frequently occurring flood disasters caused by extreme climate and urbanization processes have become the most common natural hazard and pose a great threat to human society. Therefore, urban flood risk assessment is of great significance for disaster mitigation and prevention. In this paper, the analytic hierarchy process (AHP) was applied to quantify the spatiotemporal variations in flood risk in Wuhan during 2000–2018. A comprehensive flood risk assessment index system was constructed from the hazard, sensitivity, and vulnerability components with seven indices. The results showed that the central urban area, especially the area in the west bank of the Yangtze river, had high risk due to its high flood sensitivity that was determined by land use type and high vulnerability with dense population and per unit GDP. Specifically, the Jianghan, Qiaokou, Jiangan, and Wuchang districts had the highest flood risk, more than 60% of whose area was in medium or above-medium risk regions. During 2000–2018, the flood risk overall showed an increasing trend, with Hongshan district increasing the most, and the year of 2010 was identified as a turning point for rapid risk increase. In addition, the comparison between the risk maps and actual historical inundation point records showed good agreement, indicating that the assessment framework and method proposed in this study can be useful to assist flood mitigation and management, and relevant policy recommendations were proposed based on the assessment results.
Collaborative Multimodal Writing via Google Docs: Perceptions of French FL Learners
Authors: Akoto Miriam
Published: August 2021

In spite of the growing integration of computer-mediated collaborative writing and multimodal composition in second language (L2) classrooms, research on collaborative multimodal writing, as an innovative writing pedagogy, is still underway and largely underrepresented particularly in non-English learning contexts. To bridge this research gap, the author of this study implemented a multimodal writing task in which seven French FL learners jointly created digital postcards describing their vacation activities in groups of two or three over the period of eight weeks. The study sought to explore learners’ perceptions of the benefits and challenges of this type of pedagogy and the factors mediating their writing processes. The analyses of a post-task questionnaire survey and semi-structured interviews, triangulated with the finished products, indicated that overall, collaborative multimodal writing was a motivating learning experience. Several themes emerged regarding the perceived benefits (i.e., improvement in their writing skills, genre awareness and semiotic awareness, mutual learning through peer assessment and easy synchronous writing and revising via Google Docs), as well as challenges (i.e., tensions between partners largely due to frustrations over unequal participation, lack of control over the joint text and technical glitches). This paper provides significant implications for collaborative multimodal writing research and pedagogy.
The Performance of HepG2 and HepaRG Systems through the Glass of Acetaminophen-Induced Toxicity
Authors: Lőrincz Tamás , Deák Veronika , Makk-Merczel Kinga , Varga Dóra , Hajdinák Péter , Szarka András
Published: August 2021

Investigation of drug-induced liver injuries requires appropriate in vivo and in vitro toxicological model systems. In our study, an attempt was made to compare the hepatocarcinoma HepG2 and the stem cell-derived HepaRG cell lines both in two- and three-dimensional culture conditions to find the most suitable model. Comparison of the liver-specific characteristics of these models was performed via the extent and mechanism of acetaminophen (APAP)-induced hepatotoxicity. Investigating the detailed mechanism of APAP-induced hepatotoxicity, different specific cell death inhibitors were used: the pan-caspase inhibitor zVAD-fmk and dabrafenib significantly protected both cell lines from APAP-induced cell death. However, the known specific inhibitors of necroptosis (necrostatin-1 and MDIVI) were only effective in differentiated HepaRG, which suggest a differential execution of activated pathways in the two models. By applying 3D culture methods, CYP2E1 mRNA levels could be elevated, but we failed to achieve a significant increase in hepatocyte function; hence, the 3D cultivation especially in APAP toxicity studies is not necessarily worth the complicated maintenance. Based on our findings, the hepatocyte functions of HepaRG may stand between the properties of HepG2 cells and primary hepatocytes (PHHs). However, it should be noted that in contrast to PHHs having many limitations, HepaRG cells are relatively immortal, having a stable phenotype and CYP450 expression.
Endosomal Phosphatidylinositol-3-Phosphate-Associated Functions Are Dispensable for Establishment of the Cytomegalovirus Pre-Assembly Compartment but Essential for the Virus Growth
Authors: Marcelić Marina , Lučin Hana Mahmutefendić , Begonja Antonija Jurak , Zagorac Gordana Blagojević , Lisnić Vanda Juranić , Lučin Pero
Published: August 2021

Murine cytomegalovirus (MCMV) initiates the stepwise establishment of the pre-assembly compartment (pre-AC) in the early phase of infection by the expansion of the early endosome (EE)/endosomal recycling compartment (ERC) interface and relocation of the Golgi complex. We depleted Vps34-derived phosphatidylinositol-3-phosphate (PI(3)P) at EEs by VPS34-IN1 and inhibited PI(3)P-associated functions by overexpression of 2xFYVE- and p40PX PI(3)P-binding modules to assess the role of PI(3)P-dependent EE domains in the pre-AC biogenesis. We monitored the accumulation of Rab10 and Evectin-2 in the inner pre-AC and the relocation of GM130-positive cis-Golgi organelles to the outer pre-AC by confocal microscopy. Although PI(3)P- and Vps34-positive endosomes build a substantial part of pre-AC, the PI(3)P depletion and the inhibition of PI(3)P-associated functions did not prevent the establishment of infection and progression through the early phase. The PI(3)P depletion in uninfected and MCMV-infected cells rapidly dispersed PI(3)P-bond proteins and reorganized EEs, including ablation of EE-to-ERC transport and relocation of Rab11 endosomes. The PI(3)P depletion one hour before pre-AC initiation and overexpression of 2xFYVE and p40PX domains neither prevented Rab10- and Evectin-2 accumulation, nor Golgi unlinking and relocation. These data demonstrate that PI(3)P-dependent functions, including the Rab11-dependent EE-to-ERC route, are dispensable for pre-AC initiation. Nevertheless, the virus growth was drastically reduced in PI(3)P-depleted cells, indicating that PI(3)P-associated functions are essential for the late phase of infection.
Repurposing Colchicine in Treating Patients with COVID-19: A Systematic Review and Meta-Analysis
Authors: Lien Chi-Hone , Lee Ming-Dar , Weng Shun-Long , Lin Chao-Hsu , Liu Lawrence Yu-Min , Tai Yu-Lin , Lei Wei-Te , Liu Jui-Ming , Huang Ya-Ning , Chi Hsin , Chiu Nan-Chang , Lin Chien-Yu
Published: August 2021

Coronavirus disease 2019 (COVID-19) had caused huge health losses worldwide. Several drugs had been applied to treat patients with COVID-19, and repurposing colchicine had been proposed for its anti-inflammatory properties via several pathways. In this systematic review, we evaluated the effects of colchicine treatment. From inception to May 31, 2021, databases, including PubMed, EMbase, medRxiv, and Research Square were searched, and 11 studies were enrolled. A total of 17,205 COVID-19 patients with male predominance (62.9%) were analyzed. Patients with colchicine treatment had a significantly lower risk of mortality (odds ratio (OR): 0.57, 95% confidence interval (CI): 0.38–0.87, I2: 72%; p < 0.01) and a non-significantly lower rate of mechanical ventilation (OR: 0.67, 95%CI: 0.39–1.15). The side effects were mild and not significantly different (OR: 2.03, 95%CI: 0.51–8.09). Subgroup analysis with randomized controlled trials showed no statistically significant difference in the mortality (OR: 0.80, 95%CI: 0.44–1.46, I2: 33%; p = 0.22). In conclusion, our meta-analysis found that colchicine treatment was associated with a significantly lower risk of mortality in patients with COVID-19. However, this benefit was not observed in the subgroup analysis of randomized controlled trials. Further randomized controlled studies are required to confirm the potential benefits of colchicine treatment.
3-(3-Hydroxypropyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxaldehyde Methyl Hemiacetal
Authors: Cordaro Massimiliano
Published: August 2021

The synthesis of 3-(3-hydroxypropyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carboxaldehyde as a stable methyl hemiacetal through a convenient 3-step procedure is reported. The molecule is multifunctional as it contains a formyl group, a hydroxyl group and the imide moiety. Each of these groups can play a role in specific transformations or uses.
Modeling, Optimization and Performance Evaluation of TiC/Graphite Reinforced Al 7075 Hybrid Composites Using Response Surface Methodology
Authors: Alam Mohammad Azad , Ya Hamdan H. , Yusuf Mohammad , Sivraj Ramaneish , Mamat Othman B. , Sapuan Salit M. , Masood Faisal , Parveez Bisma , Sattar Mohsin
Published: August 2021

The tenacious thirst for fuel-saving and desirable physical and mechanical properties of the materials have compelled researchers to focus on a new generation of aluminum hybrid composites for automotive and aircraft applications. This work investigates the microhardness behavior and microstructural characterization of aluminum alloy (Al 7075)-titanium carbide (TiC)-graphite (Gr) hybrid composites. The hybrid composites were prepared via the powder metallurgy technique with the amounts of TiC (0, 3, 5, and 7 wt.%), reinforced to Al 7075 + 1 wt.% Gr. The microstructural characteristics were investigated by optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) elemental mapping. A Box Behnken design (BBD) response surface methodology (RSM) approach was utilized for modeling and optimization of density and microhardness independent parameters and to develop an empirical model of density and microhardness in terms of process variables. Effects of independent parameters on the responses have been evaluated by analysis of variance (ANOVA). The density and microhardness of the Al 7075-TiC-Gr hybrid composites are found to be increased by increasing the weight percentage of TiC particles. The optimal conditions for obtaining the highest density and microhardness are estimated to be 6.79 wt.% TiC at temperature 626.13 °C and compaction pressure of 300 Mpa.
Mass Transfer Principles in Column Percolation Tests: Initial Conditions and Tailing in Heterogeneous Materials
Authors: Liu Binlong , Finkel Michael , Grathwohl Peter
Published: August 2021

Initial conditions (pre-equilibrium or after the first flooding of the column), mass transfer mechanisms and sample composition (heterogeneity) have a strong impact on leaching of less and strongly sorbing compounds in column percolation tests. Mechanistic models as used in this study provide the necessary insight to understand the complexity of column leaching tests especially when heterogeneous samples are concerned. By means of numerical experiments, we illustrate the initial concentration distribution inside the column after the first flooding and how this impacts leaching concentrations. Steep concentration gradients close to the outlet of the column have to be expected for small distribution coefficients (Kd<1 L kg−1) and longitudinal dispersion leads to smaller initial concentrations than expected under equilibrium conditions. In order to elucidate the impact of different mass transfer mechanisms, film diffusion across an external aqueous boundary layer (first order kinetics, FD) and intraparticle pore diffusion (IPD) are considered. The results show that IPD results in slow desorption kinetics due to retarded transport within the tortuous intragranular pores. Non-linear sorption has not much of an effect if compared to Kd values calculated for the appropriate concentration range (e.g., the initial equilibrium concentration). Sample heterogeneity in terms of grain size and different fractions of sorptive particles in the sample have a strong impact on leaching curves. A small fraction (<1%) of strongly sorbing particles (high Kd) carrying the contaminant may lead to very slow desorption rates (because of less surface area)—especially if mass release is limited by IPD—and thus non-equilibrium. In contrast, mixtures of less sorbing fine material (“labile” contamination with low Kd), with a small fraction of coarse particles carrying the contaminant leads to leaching close to or at equilibrium showing a step-wise concentration decline in the column effluent.
Red Emission Carbon Dots Prepared by 1,4-Diaminonaphthalene for Light-Emitting Diode Application and Metal Ion Detection
Authors: An Yulong , Lin Xu , Guo Zewen , Yin Qitao , Li Yan , Zheng Yunwu , Shi Zhengjun , Zhang Wuxian , Liu Can
Published: August 2021

Carbon dots (CDs), as the most important type of carbon materials, have been widely used in many fields because of their unique fluorescence characteristics and excellent properties of biocompatibility. In previous studies, the fluorescence of CDs was mainly concentrated in the blue and green, whereas the red fluorescence was relatively less. Herein, we prepared efficient red-emitting CDs from 1,4-diaminonaphthalene using solvothermal methods. We discussed the effects of different solvothermal solvents on CDs. The results show that CDs prepared with octane and acetone as reaction media have the best fluorescence properties. The CDs dispersed in different organic solvents exhibited tunable emission across a wide spectrum from 427 nm to 679 nm. We further demonstrated the application of red light-emitting diode (LED) optoelectronics and fluorescence detection of Fe3+ in aqueous solution.
Energy Dissipated in Fatigue and Creep Conditions
Authors: Mroziński Stanisław , Lis Zbigniew , Egner Halina
Published: August 2021

The paper presents the results of tests performed on samples made of P91 steel under combined variable and constant load conditions, at temperature T = 600 °C. The analysis of the test results was carried out with the use of the energetic description of the fatigue process. It was shown that the order of occurrence of the fatigue load and creep in the load program influences the fatigue life and the value of the energy cumulated in the sample until fracture.
Studies towards the Synthesis of Novel 3-Aminopropoxy-Substituted Dioxins Suitable for the Development of Aptamers for Photonic Biosensor Applications
Authors: Kalantzi Stefania , Leonardi Sofia , Vachlioti Eleanna , Kaliatsi Eleni G. , Papachristopoulou Κοnstantina , Stathopoulos Constantinos , Vainos Nikolaos , Papaioannou Dionissios
Published: August 2021

Hydroxy-substituted tetrachlorodibenzo[b,e][1,4]dioxin and tetrachlorodibenzo[b,d]furans have been synthesized using 3,4-dichloroanisole, 2,3,6-trichlorophenol and 4,5-dichlorocatechol as starting materials and electrophilic and/or nucleophilic aromatic substitution reactions for the assembly of the dibenzo[b,e][1,4]dioxin and dibenzo[b,d]furan systems. The thus-obtained phenolic compounds were then alkylated with N-1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl (Dde)-protected 3-bromopropan-1-amine to give the corresponding N-Dde protected 3-aminopropoxy-substituted tetrachlorodibenzo[b,e][1,4]dioxin and tetrachlorodibenzo[b,d]furans, respectively. Hydrazinolysis-mediated Dde removal from the former compound provided the corresponding amino-substituted dioxin, which was coupled to carboxy-substituted magnetic beads affording magnetic beads coated by the amino-substituted dioxin. The latter is an attractive intermediate for the development of selective single-standard DNA (ssDNA) aptamers, which constitute molecular recognition elements in photonic biosensors with potential application to the monitoring of the dangerous environmental pollutants, dioxins having serious implications in human health.
Application of Saccharomyces cerevisiae/Calcium Alginate Composite Beads for Cephalexin Antibiotic Biosorption from Aqueous Solutions
Authors: Rusu Lăcrămioara , Grigoraș Cristina-Gabriela , Simion Andrei-Ionuț , Suceveanu Elena Mirela , Șuteu Daniela , Harja Maria
Published: August 2021

Cephalexin (CPX) is recognized as a water pollutant, and it has been listed in a number of countries with a risk factor greater than one. Herein, the present work focused on the synthesis, characterization and biosorption capacity evaluation of Saccharomyces cerevisiae immobilized in calcium alginate as a biosorbent to remove CPX from aqueous solutions. Biosorbent was characterized by SEM and FTIR techniques. Batch biosorption experiments were conducted in order to evaluate the effect of the initial pH, biosorbent dose and CPX initial concentration. The removal efficiency, in considered optimal conditions (pH = 4, CPX initial concentration = 30 mg/L, biosorbent dose = 1 g/L) was 86.23%. CPX biosorption was found to follow the pseudo–second-order kinetics. The equilibrium biosorption data were a good fit for the Langmuir model with correlation coefficient of 0.9814 and maximum biosorption capacity was 94.34 mg/g. This study showed that the synthesized biosorbent by immobilization technique is a low-cost one, easy to obtain and handle, eco-friendly, with high feasibility to remove CPX antibiotic from aqueous solution. The findings of this study indicate that the biosorbents based on microorganisms immobilized on natural polymers have the potential to be applied in the treatment of wastewater.
Tensile Strength of Artificially Cemented Sandstone Generated via Microbially Induced Carbonate Precipitation
Authors: Konstantinou Charalampos , Biscontin Giovanna , Logothetis Fotios
Published: August 2021

Artificially bio-cemented sands treated with microbially induced calcite precipitation are weakly cemented rocks representing intermediate materials between locked and carbonate sands. Variations in cementation significantly affect the strength of sample, particularly tensile stregth. The modes of fracture and the surface characteristics resulting from the indirect tensile strength tests (Brazilian tests) are strongly correlated with the specimen strength and consequently the degree of cementation. This study examines the tensile strength of bio-cemented fine and coarse sands (average particle diameter 0.18 and 1.82 mm, respectively) and investigates failure modes by recording fracture evolution at both sides of specimen and surface characteristics of the reconstructed surfaces. The dimensionless slope parameter Z2 provided the best fit with respect to tensile strength while the power spectral density was a good indicator of surface anisotropy. Finally, wavelet decomposition allowed for comparison of fracture surface characteristics of the two sands ignoring the grain size effects.
Experimental Study on Thermal Runaway Process of 18650 Lithium-Ion Battery under Different Discharge Currents
Authors: Li Lun , Ju Xiaoyu , Zhou Xiaodong , Peng Yang , Zhou Zhizuan , Cao Bei , Yang Lizhong
Published: August 2021

Lithium-ion batteries (LIBs) subjected to external heat may be prone to failure and cause catastrophic safety issues. In this work, experiments were conducted to investigate the influence of discharge current on the thermal runaway process under thermal abuse. The calibrated external heat source (20 W) and discharge currents from 1 to 6 A were employed to match the thermal abuse conditions in an operational state. The results indicated that the key parameters during the failure process, such as the total mass loss, the onset temperatures of safety venting and thermal runaway, and the peak temperature, are ultimately determined by the capacity inside the battery, and the discharge current can hardly change it. However, discharge currents can produce extra energy to accelerate the thermal runaway process. Compared with the battery in an open circuit, the onset time of thermal runaway was reduced by 7.4% at 6 A discharge. To quantify the effect of discharge current, the total heat generation by discharge current was calculated. The results show that a heat generation of 1.6 kJ was produced when the battery was discharged at 6 A, which could heat the cell to 34 °C (neglect of heat loss). This study simulates the failure process of the LIB in the operational state, which is expected to help the safety application of LIB and improve the reliability of the battery management system.
Operational Variables on the Processing of Porous Titanium Bodies by Gelation of Slurries with an Expansive Porogen
Authors: Sanchez-Herencia Antonio Javier , Gonzalez Zoilo , Rodriguez Alejandro , Molero Esther , Ferrari Begoña
Published: August 2021

Colloidal processing techniques, based on the suspension of powders in a liquid, are very versatile techniques to fabricate porous structures. They can provide customized pores, shapes and surfaces through the control of operational parameters, being the base of the alternative additive manufacture processes. In this work disperse and stable titanium aqueous slurries has been formulated in order to process porous materials by the incorporation of methylcellulose (MC) as a gelation agent and ammonium bicarbonate as an expansive porogen. After casting the slurries and heating at mild temperatures (60–80 °C) the methylcellulose gels and traps the gas bubbles generated by the ammonium bicarbonate decomposition to finally obtain stiff porous green structures. Using an experimental design method, the influence of the temperature as well as the concentration of gelation agent and porogen on the viscosity, apparent density and pore size distribution is analyzed by a second-order polynomial function in order to identifying the influence of the operating variables in the green titanium porous compact. After sintering at 1100 °C under high vacuum, titanium sponges with 39% of open porosity and almost no close porosity were obtained.
Zinc Oxide Nanoparticles for Water Purification
Authors: Spoială Angela , Ilie Cornelia-Ioana , Trușcă Roxana-Doina , Oprea Ovidiu-Cristian , Surdu Vasile-Adrian , Vasile Bogdan Ștefan , Ficai Anton , Ficai Denisa , Andronescu Ecaterina , Dițu Lia-Mara
Published: August 2021

In this study, zinc oxide nanoparticles were synthesized through a simple co-precipitation method starting from zinc acetate dihydrate and sodium hydroxide as reactants. The as-obtained ZnO nanoparticles were morphologically and structurally characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photocatalytic activity, and by determining the antimicrobial activity against Gram-negative and Gram-positive bacteria. The XRD pattern of the zinc oxide nanoparticles showed the wurtzite hexagonal structure, and its purity highlighted that the crystallinity correlated with the presence of a single product, zinc oxide. The ZnO nanoparticles have an average crystallite size of 19 ± 11 nm, which is in accordance with the microscopic data. ZnO nanoparticles were tested against methyl orange, used as a model pollutant, and it was found that they exhibit strong photocatalytic activity against this dye. The antibacterial activity of ZnO nanoparticles was tested against Gram-negative and Gram-positive strains (Escherichia coli, Staphylococcus aureus, and Candida albicans). The strongest activity was found against Gram-positive bacteria (S. aureus).
Physicochemical and Optical Characterization of Citrus aurantium Derived Biochar for Solar Absorber Applications
Authors: Gonzalez-Canche Nancy G. , Carrillo Jose G. , Escobar-Morales Beatriz , Salgado-Tránsito Iván , Pacheco Neith , Pech-Cohuo Soledad Cecilia , Peña-Cruz Manuel I.
Published: August 2021

Agro-industrial waste valorization is an attractive approach that offers new alternatives to deal with shrinkage and residue problems. One of these approaches is the synthesis of advanced carbon materials. Current research has shown that citrus waste, mainly orange peel, can be a precursor for the synthesis of high-quality carbon materials for chemical adsorption and energy storage applications. A recent approach to the utilization of advanced carbon materials based on lignocellulosic biomass is their use in solar absorber coatings for solar-thermal applications. This study focused on the production of biochar from Citrus aurantium orange peel by a pyrolysis process at different temperatures. Biochars were characterized by SEM, elemental analysis, TGA-DSC, FTIR, DRX, Raman, and XPS spectroscopies. Optical properties such as diffuse reflectance in the UV−VIS−NIR region was also determined. Physical-chemical characterization revealed that the pyrolysis temperature had a negative effect in yield of biochars, whereas biochars with a higher carbon content, aromaticity, thermal stability, and structural order were produced as the temperature increased. Diffuse reflectance measurements revealed that it is possible to reduce the reflectance of the material by controlling its pyrolysis temperature, producing a material with physicochemical and optical properties that could be attractive for use as a pigment in solar absorber coatings.
A Green, Simple and Facile Way to Synthesize Silver Nanoparticles Using Soluble Starch. pH Studies and Antimicrobial Applications
Authors: Pascu Bogdan , Negrea Adina , Ciopec Mihaela , Duteanu Narcis , Negrea Petru , Nemeş Nicoleta Sorina , Seiman Corina , Marian Eleonora , Micle Otilia
Published: August 2021

Along with the progress of nanoscience and nanotechnology came the means to synthesize nanometric scale materials. While changing their physical and chemical properties, they implicitly changed their application area. The aim of this paper was the synthesis of colloidal silver nanoparticles (Ag-NPs by ultrasonic disruption), using soluble starch as a reducing agent and further as a stabilizing agent for produced Ag-NPs. In this context, an important parameter for Ag-NPs preparation is the pH, which can determine the particle size and stability. The physical-chemical behavior of the synthesized Ag-NPs (shape, size, dispersion, electric charge) is strongly influenced by the pH value (experiment being conducted for pH values in the range between 8 and 13). The presence of a peak located at 412 nm into the UV-VIS spectra demonstrates the presence of silver nano-spheres into the produced material. In UV/VIS spectra, we observed a specific peak for yellow silver nano-spheres located at 412 nm. Samples characterization was performed by scanning electron microscopy, SEM, energy-dispersive X-ray spectroscopy, EDX, Fourier-transform infrared spectroscopy, and FT-IR. For all Ag-NP samples, we determined the zeta and observed that the Ag-NP particles obtained at higher pH and have better stability. Due to the intrinsic therapeutic properties and broad antimicrobial spectrum, silver nanoparticles have opened new horizons and new approaches for the control of different types of infections and wound healing abilities. In this context, the present study also aims to confirm the antimicrobial effect of prepared Ag-NPs against several bacterial strains (indicator and clinically isolated strains). In this way, it was confirmed that the antimicrobial activity of synthesized Ag-NPs was good against Staphylococcus aureus (ATCC 25923 and S. aureus MSSA) and Escherichia coli (ATTC 25922 and clinically isolated strain). Based on this observation, we conclude that the prepared Ag-NPs can represent an alternative or auxiliary material used for controlling important nosocomial pathogens. The fungal reference strain Candida albicans was more sensitive at Ag-NPs actions (zone of inhibition = 20 mm) compared with the clinically isolated strain (zone of inhibition = 10 mm), which emphasizes the greater resistance of fungal strains at antimicrobial agent’s action.
A Survey of Machine Learning-Based Solutions for Phishing Website Detection
Authors: Tang Lizhen , Mahmoud Qusay H.
Published: August 2021

With the development of the Internet, network security has aroused people’s attention. It can be said that a secure network environment is a basis for the rapid and sound development of the Internet. Phishing is an essential class of cybercriminals which is a malicious act of tricking users into clicking on phishing links, stealing user information, and ultimately using user data to fake logging in with related accounts to steal funds. Network security is an iterative issue of attack and defense. The methods of phishing and the technology of phishing detection are constantly being updated. Traditional methods for identifying phishing links rely on blacklists and whitelists, but this cannot identify new phishing links. Therefore, we need to solve how to predict whether a newly emerging link is a phishing website and improve the accuracy of the prediction. With the maturity of machine learning technology, prediction has become a vital ability. This paper offers a state-of-the-art survey on methods for phishing website detection. It starts with the life cycle of phishing, introduces common anti-phishing methods, mainly focuses on the method of identifying phishing links, and has an in-depth understanding of machine learning-based solutions, including data collection, feature extraction, modeling, and evaluation performance. This paper provides a detailed comparison of various solutions for phishing website detection.
A Proposal for the Optimisation of Algorithms for the Calculation of the Energy Demands of Residential Housing
Authors: Hermosilla Pamela , Quiroz Claudio , Cabrejos Francisco , Muñoz-La Rivera Felipe
Published: August 2021

In response to increased energy consumption and CO2 emissions, various energy efficiency policies, standards and housing certifications have emerged around the world. These aim to measure and quantify energy efficiency and endorse homes for meeting certain standards according to consistent categories that vary by continent or country. These energy rating systems correspond to a series of criteria and formulations that, through the calculation and combination of multiple variables, establish the classification values. In Chile, there is the Energy Rating System for Housing (CEV), which performs energy efficiency calculations using dynamic heat balance spreadsheets in Microsoft® Excel. When applied for everyday use and at a large scale, this system has the disadvantage of requiring a great deal of processing time for each simulation. This research proposes an improvement to the CEV energy demand calculation mechanism by generating a solution that takes advantage of the use of multiprocessors and implements the various algorithms in the C programming language. The results show that the CEV values obtained with the proposed calculation engine are equal to those of the current system but demonstrate a 76.5% improvement in their processing time.
Sequential Interval Reliability for Discrete-Time Homogeneous Semi-Markov Repairable Systems
Authors: Barbu Vlad Stefan , D’Amico Guglielmo , Gkelsinis Thomas
Published: August 2021

In this paper, a new reliability measure, named sequential interval reliability, is introduced for homogeneous semi-Markov repairable systems in discrete time. This measure is the probability that the system is working in a given sequence of non-overlapping time intervals. Many reliability measures are particular cases of this new reliability measure that we propose; this is the case for the interval reliability, the reliability function and the availability function. A recurrent-type formula is established for the calculation in the transient case and an asymptotic result determines its limiting behaviour. The results are illustrated by means of a numerical example which illustrates the possible application of the measure to real systems.
Seasonality in Tourism: Do Senior Programs Mitigate It?
Authors: Rico Paz , Cabrer-Borrás Bernardí , Morillas-Jurado Francisco
Published: August 2021

Seasonality is a widely recognised and accredited phenomenon known to cause an imbalance in tourism activity throughout the year, prompting tourist destinations, both public and private, to consider how best to plan the use of their resources. One way of mitigating the economic imbalances that seasonality can cause is to find strategies for seasonal adjustment, such as travel programmes aimed at the elderly. This paper analyses the seasonality of tourism activity in some EU countries, and in particular in Spain. Different indicators are used to compare the results and carry out a sensitivity analysis. The study then focuses on tourism programmes for the elderly in Spain to see whether this type of programme helps to alleviate the seasonality of tourism activity. To corroborate this, an econometric model is specified and estimated, which enables the scope of these programmes to be compared.
Dynamical Behavior Analysis of a Time-Delay SIRS-L Model in Rechargeable Wireless Sensor Networks
Authors: Liu Guiyun , Li Junqiang , Liang Zhongwei , Peng Zhimin
Published: August 2021

The traditional SIRS virus propagation model is used to analyze the malware propagation behavior of wireless rechargeable sensor networks (WRSNs) by adding a new concept: the low-energy status nodes. The SIRS-L model has been developed in this article. Furthermore, the influence of time delay during the charging behavior of the low-energy status nodes needs to be considered. Hopf bifurcation is studied by discussing the time delay that is chosen as the bifurcation parameter. Finally, the properties of the Hopf bifurcation are explored by applying the normal form theory and the center manifold theorem.
Leveraging Elasticity to Uncover the Role of Rabinowitsch Suspension through a Wavelike Conduit: Consolidated Blood Suspension Application
Authors: Abdelsalam Sara I. , Zaher Abdullah Z.
Published: August 2021

The present work presents a mathematical investigation of a Rabinowitsch suspension fluid through elastic walls with heat transfer under the effect of electroosmotic forces (EOFs). The governing equations contain empirical stress-strain equations of the Rabinowitsch fluid model and equations of fluid motion along with heat transfer. It is of interest in this work to study the effects of EOFs, which are rigid spherical particles that are suspended in the Rabinowitsch fluid, the Grashof parameter, heat source, and elasticity on the shear stress of the Rabinowitsch fluid model and flow quantities. The solutions are achieved by taking long wavelength approximation with the creeping flow system. A comparison is set between the effect of pseudoplasticity and dilatation on the behaviour of shear stress, axial velocity, and pressure rise. Physical behaviours have been graphically discussed. It was found that the Rabinowitsch and electroosmotic parameters enhance the shear stress while they reduce the pressure gradient. A biomedical application to the problem is presented. The present analysis is particularly important in biomedicine and physiology.
Design of Optimal Controllers for Unknown Dynamic Systems through the Nelder–Mead Simplex Method
Authors: Tsai Hsun-Heng , Fuh Chyun-Chau , Ho Jeng-Rong , Lin Chih-Kuang
Published: August 2021

This paper presents an efficient method for designing optimal controllers. First, we established a performance index according to the system characteristics. In order to ensure that this performance index is applicable even when the state/output of the system is not within the allowable range, we added a penalty function. When we use a certain controller, if the state/output of the system remains within the allowable range within the preset time interval, the penalty function value is zero. Conversely, if the system state/output is not within the allowable range before the preset termination time, the experiment/simulation is terminated immediately, and the penalty function value is proportional to the time difference between the preset termination time and the time at which the experiment was terminated. Then, we used the Nelder–Mead simplex method to search for the optimal controller parameters. The proposed method has the following advantages: (1) the dynamic equation of the system need not be known; (2) the method can be used regardless of the stability of the open-loop system; (3) this method can be used in nonlinear systems; (4) this method can be used in systems with measurement noise; and (5) the method can improve design efficiency.